Ulsan, South Korea
Ulsan, South Korea

The University of Ulsan was founded on February 19, 1969 as the Ulsan Institute of Technology. The University was promoted to a full-fledged University on March 1, 1985. The university is located in Mugeo-dong, Ulsan, South Korea. The University currently has approximately 10,500 students enrolled.The city of Ulsan has been recognized as the Korean city which was built around the corporate base of the multinational Hyundai conglomerate. Thus, the Hyundai Conglomerate announced its plan to give 40 billion won to assist a variety of university-industry cooperation projects.This corporate relationship has helped turn the University into one of South Korea's top rated institutions for graduate job placement, as well as increasing its reputation more broadly as one of the top private universities outside of Seoul. Wikipedia.

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Kim K.-T.,University of Ulsan | Hur J.,University of Ulsan | Kang G.-H.,Korea Marine Equipment Research Institute
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

We performed circulating modeling before the studying inter turn fault. It used a finite element method (FEM)-based model to consider the magnetic non-linearity. By integrating the developed model with a current-controlled voltage source inverter (CCVSI) model, the distributed characteristics of an inter-turn fault operated by six-switched inverter are investigated considering the speed control. Also, this paper presents flux density distribution and torque characteristic to analyze the inter turn fault of interior permanent magnet (IPM) type BLDC motor having inter-turn fault. Also, we proposed new fault impedance modeling for magnetic characteristics analysis. The fault impedance is required to calculate the circulating current that causes magnetic distortion. Thus, this paper proposes a method for estimation of the circulating current taking into account the voltage at the shorted turn and the rotating speed. The analysis data were verified experimentally. © 2011 IEEE.

Sun H.-D.,Kyungpook National University | Park M.-Y.,Kyungpook National University | Park J.-H.,Kyungpook National University | Kim H.-G.,Kyungpook National University | And 2 more authors.
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

This paper proposed a new multi-level inverter topology based on a H-bridge with two switches and two diodes connected to the DC-link. The output voltage of the proposed topology is quite closer to a sinusoidal waveform compared with a typical single phase inverter. The proposed multi-level inverter is applicable to a power conditioning system for renewable energy sources, and it can be also used as a building block of a cascaded multi-level inverter for a high voltage application. In case of conventional H-bridge type or NPC type multi-level inverter, 8 controllable switches are used to obtain a 5 level output voltage, but the proposed multi-level inverter requires only 6 controllable switches. Thus the circuit configuration is quite simple, reliable and cost-effective implementation is possible. The efficiency can be improved owing to the reduction of the switching loss. A new PWM method based on POD modulation is suggested which requires only one carrier signal. The switching sequence to make the capacitor voltage balanced is also considered. The feasibility is studied through simulation and experiment. © 2011 IEEE.

Nguyen T.D.,University of Ulsan | Lee H.-H.,University of Ulsan
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

The matrix converters are a good alternative to back-to-back converter in variable speed AC generation to supply energy to a stand-alone load or grid. In case of the unbalanced load, the four-leg matrix converter is required because this topology can effectively provide a path of neutral current. In this paper, a carrier-based PWM modulation is proposed to control the four-leg very sparse matrix converter. The proposed method has less computation complexity for digital signal processor. The algorithm uses only one carrier signal to generate PWMs for both rectifier stage and inverter stage control. The simulation and experimental results are provided to validate the feasibility of the proposed method. © 2011 IEEE.

Trinh Q.-N.,University of Ulsan | Lee H.-H.,University of Ulsan | Chun T.-W.,University of Ulsan
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

In this paper, a new Z-source inverter (ZSI) topology is developed to improve a voltage boost ability of ZSI. Some more inductors and diodes are added into the impedance network of the conventional ZSI. The modulation methods that have been developed in the conventional ZSI can be easily utilized in the proposed ZSI. The voltage boost ratio becomes much higher compared with the conventional ZSI under the same shoot-through duty ratio. In addition, the proposed ZSI can reduce the voltage stress on Z-source capacitor and inverter-bridge significantly because a smaller shoot-through duty ratio is required for high voltage boost ratio. Theoretical analysis of the proposed topology is investigated and the improved performances are validated by both simulation study and experimental results. © 2011 IEEE.

Lee S.-K.,Korea Marine Equipment Research Institute | Kang G.-H.,Korea Marine Equipment Research Institute | Hur J.,University of Ulsan
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

The purpose of this paper is to provide the radial force and vibration mode comparison between two large interior permanent magnet machines (IPM) with different pole-slot combination considering stator and rotor eccentricity. Due to the punching tolerance, the mixed eccentricity of air-gap is inevitable. It will generate the asymmetric magnetic flux density in air-gap, which makes the unbalanced magnetic pull and vibration. The study is focused on the unbalanced magnetic force and their harmonics according to eccentricity condition such as static, dynamic and mixed. When the high vibration is produced especially resonance, the obtained results provide a clue what eccentricity condition occurs in the machine. © 2011 IEEE.

Lee S.-H.,University of Maryland University College | Kim J.-M.,University of Ulsan | Yoon J.-R.,R&D Center
Journal of Ceramic Processing Research | Year: 2017

We successfully prepared urchin-like TiO2 material composed of numerous nanorods by hydrothermal method. After that, a cylindrical hybrid supercapacitor was fabricated by using urchin-like TiO2 anode and activated carbon cathode. The energy and power density of hybrid supercapacitor using urchin-like TiO2 ranged from 10.134 to 50.648 Wh kg−1 and from 194.412 to 12224.356 W kg−1, higher than those of hybrid supercapacitors using Li4Ti5O12 anode. It also shows the extraordinary cycle performance of 93.6% at 3.0 Ag−1 after 1000 cycles. As a result, we can conclude that urchin-like TiO2 can be regarded as high efficiency anode for hybrid supercapacitors. © 2017, Hanyang University. All rights reserved.

Lee S.D.,University of Ulsan | Mallampati S.R.,University of Ulsan | Lee B.H.,University of Ulsan
Journal of the Air and Waste Management Association | Year: 2017

A novel nanosize metallic calcium/iron dispersed reagent was synthesized and tested as coagulant/catalyst in a hybrid zero valent iron (ZVI)/H2O2 oxidation process to treat leachate. Two different types of leachates, one from municipal solid waste (MSW) tipping hall (MSWIL) and second from an MSW landfill site (MSWLL), were collected and characterized. The morphology, elemental composition, and mineral phases of the nano-Ca/CaO and nano-Fe/Ca/CaO were characterized by scanning electron microscopy–electron dispersive spectroscopy (SEM-EDS) and x-ray powder diffraction (XRD) analysis. The coagulation process with 2.5 g L−1 nano-Ca/CaO attained 64.0, 56.0, and 20.7% removal of color, chemical oxygen demand (COD), and total suspended solids (TSS) in MSWLL. With only 1.0 g L−1 of nano-Fe/Ca/CaO, relatively high color, COD and TSS removal was achieved in MSWLL at 67.5, 60.2, and 37.7%, respectively. The heavy metal removal efficiency reached 91–99% after treatment with nano-Fe/Ca/CaO in both leachate samples. The coupling process, using 1.0 g L−1 of nano-Fe/Ca/CaO and 20 mM H2O2 doses, achieved enhancement removal of color, COD, and TSS, up to 95%, 96%, and 66%, respectively, without initial pH control. After this treatment, the color, COD, TSS, and heavy metals were significantly decreased, fitting the Korean discharge regulation limit. A hybrid coupled zero valent iron (ZVI)/H2O2 oxidation process with novel nanosized metallic calcium/iron dispersed reagent proved to be a suitable treatment for dealing with leachate samples. Implications: Conventional treatments (biological or physicochemical) are not sufficient anymore to reach the level of purification needed to fully reduce the negative impact of landfill leachates on the environment. This implies that new treatment alternatives species must be proposed. A coupled zero valent iron (ZVI)/H2O2 oxidation process proved to be a suitable treatment for dealing with leachate samples. Coagulation with nFe/Ca/CaO allows 91–99% of heavy metals removal. The coupled coagulation–oxidation process by nFe/Ca/CaO reveals excellent ability to treat leachate. After coupled treatment the color, COD, and TSS were also much lower than the discharge regulation limit. © 2017 A&WMA.

Lee J.A.,University of Ulsan | Lee S.,National Evidence Based Healthcare Collaborating Agency | Cho H.-J.,University of Ulsan
International Journal of Environmental Research and Public Health | Year: 2017

Introduction: The prevalence of adolescent electronic cigarette (e-cigarette) use has increased in most countries. This study aims to determine the relation between the frequency of e-cigarette use and the frequency and intensity of cigarette smoking. Additionally, the study evaluates the association between the reasons for e-cigarette use and the frequency of its use. Materials and Methods: Using the 2015 Korean Youth Risk Behavior Web-Based Survey, we included 6655 adolescents with an experience of e-cigarette use who were middle and high school students aged 13–18 years. We compared smoking experience, the frequency and intensity of cigarette smoking, and the relation between the reasons for e-cigarette uses and the frequency of e-cigarette use. Results: The prevalence of e-cigarette ever and current (past 30 days) users were 10.1% and 3.9%, respectively. Of the ever users, approximately 60% used e-cigarettes not within 1 month. On the other hand, 8.1% used e-cigarettes daily. The frequent and intensive cigarette smoking was associated with frequent e-cigarette uses. The percentage of frequent e-cigarette users (≥10 days/month) was 3.5% in adolescents who did not smoke within a month, but 28.7% among daily smokers. Additionally, it was 9.1% in smokers who smoked less than 1 cigarette/month, but 55.1% in smokers who smoked ≥20 cigarettes/day. The most common reason for e-cigarette use was curiosity (22.9%), followed by the belief that they are less harmful than conventional cigarettes (18.9%), the desire to quit smoking (13.1%), and the capacity for indoor use (10.7%). Curiosity was the most common reason among less frequent e-cigarette users; however, the desire to quit smoking and the capacity for indoor use were the most common reasons among more frequent users. Conclusions: Results showed a positive relation between frequency or intensity of conventional cigarette smoking and the frequency of e-cigarette use among Korean adolescents, and frequency of e-cigarette use differed according to the reason for the use of e-cigarettes. © 2017 by the authors; licensee MDPI, Basel, Switzerland.

Bae K.,University of Ulsan
WCTE 2016 - World Conference on Timber Engineering | Year: 2016

The aim of this article is for the necessity of wood culture and urban tectonic as practical strategy in Korea. Architecture is not mere result of physical form or style but culture of the day combined people's wisdom and thought. Therefore, the recovery of wood culture is important for the future of Korean architecture. The Wood culture is defined as common values, knowledge, norms and lifestyle of the social members who prefer to use wood products, and it is expression of hearts for forest, which embodies emotional and physical value, and thus culture of life and furnish are finally included in wood culture. It is very important for architectural identity to make an urban tectonic which is the art of assembling the local materials used in construction for high-level values. There is a couple of practical progressive strategies, which could promote and expand wooden architecture are necessary. The first strategy is wooden architecture of urban commercial housing or multiple housing, and another is to implement infill wall that can increase energy performance of old apartments needed for redevelopment.

Lee M.-S.,University of Ulsan | Kim H.J.,University of Ulsan
Epidemiology and health | Year: 2016

In April 2011 a tertiary hospital located in Seoul, Korea reported several cases of severe respiratory distress of unknown origin in young adults. To find the route of transmission, causative agent and patient risk factors of the outbreak, an investigation of the epidemic was initiated. A hospital based case-control study was conducted to indicate that humidifier detergent use was the cause of the outbreak. This information led the Ministry of Health and Welfare of Korea issued an order that humidifier detergents should be withdrawn from the market. Here, we describe the major events of planning, execution, and interpretation of the study, and discussions between researchers and public authorities following the decision to perform an epidemiologic study, chronologically.

Lim J.,University of Ulsan | Kong Y.-G.,University of Ulsan | Kim Y.-K.,University of Ulsan | Hong B.,University of Ulsan
International Journal of Medical Sciences | Year: 2017

Background: Hand-assisted laparoscopic donor nephrectomy is a minimally invasive procedure for living kidney donation. The surgeon operative volume is associated with postoperative morbidity and mortality. We evaluated the risk factors associated with decreased renal function after hand-assisted laparoscopic donor nephrectomy performed by a single experienced surgeon. Methods: We included living renal donors who underwent hand-assisted laparoscopic donor nephrectomy by a single experienced surgeon between 2006 and 2013. Decreased renal function was defined as an estimated glomerular filtration rate (eGFR) of < 60 mL/min/1.73 m2 on postoperative day 4. The donors were categorized into groups with postoperative eGFR < 60 mL/min/1.73 m2 or ≥ 60 mL/min/1.73 m2. Univariate and multivariate logistic regression analyses were performed to evaluate the risk factors associated with decreased renal function after hand-assisted laparoscopic donor nephrectomy. The hospital stay duration, intensive care unit admission rate, and eGFR at postoperative year 1 were evaluated. Results: Of 643 patients, 166 (25.8%) exhibited a postoperative eGFR of < 60 mL/min/1.73 m2. Multivariate logistic regression analysis demonstrated that the risk factors for decreased renal function were age [odds ratio (95% confidence interval), 1.062 (1.035–1.089), P < 0.001], male sex [odds ratio (95% confidence interval), 3.436 (2.123–5.561), P < 0.001], body mass index (BMI) [odds ratio (95% confidence interval), 1.093 (1.016–1.177), P = 0.018], and preoperative eGFR [odds ratio (95% confidence interval), 0.902 (0.881–0.924), P < 0.001]. There were no significant differences in postoperative hospital stay duration and intensive care unit admission rate between the two groups. In addition, 383 of 643 donors were analyzed at postoperative year 1. Sixty donors consisting of 14 (5.0%) from the group of 279 donors in eGFR ≥ 60 mL/min/1.73 m2, and 46 (44.2%) from the group of 104 donors in eGFR < 60 mL/min/1.73 m2 had eGFR < 60 mL/min/1.73 m2 at postoperative year 1 (P < 0.001). Conclusions: Increased age, male sex, higher BMI, and decreased preoperative eGFR were risk factors for decreased renal function after hand-assisted laparoscopic donor nephrectomy by a single experienced surgeon. These results provide important evidence for the safe perioperative management of living renal donors. © Ivyspring International Publisher.

Phan D.-M.,University of Ulsan | Nguyen C.-L.,École de Technologie Supérieure of Montreal | Lee H.-H.,University of Ulsan
ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings | Year: 2016

This paper proposes a robust and flexible control strategy for a single-phase unified power quality conditioner (S-UPQC) to solve the power quality problem due to the distorted input supply voltage and the nonlinear load. In order to enhance the performance of the series and shunt active power filters (APFs) in S-UPQC, an advanced current and voltage control schemes are introduced based on the modified repetitive controller (RCs) connected with a proportional-integral (PI) controller. Unlike the conventional control scheme for the series and shunt APFs, the proposed scheme is implemented without any harmonic extractor. Furthermore, the dynamic performance is improved significantly due to the reduced delay time of the RC, and the computation time is also reduced. The effectiveness of the proposed control schemes for the S-UPQC is validated through simulation. © 2016 IEEE.

Seo Y.-T.,University of Ulsan | Park J.-Y.,University of Ulsan | Choi S.-J.,University of Ulsan
ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings | Year: 2016

Photovoltaic (PV) model can be a viable alternative to the conventional look-up-table as an accurate and versatile solar array simulator (SAS) engine. In PV model-based SAS, PV model has a critical role to generate appropriate I-V characteristic of the PV panel under rapidly varying temperature and irradiation, and its calculation speed as well as accuracy are key performances. In this paper, a novel algorithm that is suitable for such a SAS engine is proposed. The suggested method adopts conjugate gradient optimization to extract PV model parameters from the changing conditions and to reconstruct the exact I-V curve very rapidly. For the verification, the proposed algorithm is compared with conventional ones which have been widely used in the PV model extraction. As a result, the proposed model shows superior calculation speed with good accuracy. © 2016 IEEE.

Park J.-K.,University of Ulsan | Wellawatta T.,University of Ulsan | Choi S.-J.,University of Ulsan | Hur J.,Incheon National University
ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings | Year: 2016

In this study, we propose the mitigation method of a shaft voltage according to change in parasitic capacitances of a permanent magnet synchronous motor (PMSM). First, we designed the equivalent circuit taking into account all parasitic capacitances. Then, we deducted that rotor-to-winding and stator-to-rotor capacitances mainly affect the shaft voltage. The stator-to-rotor capacitance depends on the air-gap length, which directly affects output torque characteristics of the motor. In case of the rotor-to-winding capacitance, it depends on the distance from the rotor to winding, which have effects on torque ripple, but it doesn't affect average torque of the motor. Thus, rotor-to-winding capacitance is determined as a variable for mitigation of the shaft voltage. According to change in the rotor-to-winding capacitance, we obtained and compared the results of the shaft voltage, average torque, and torque ripple. © 2016 IEEE.

Kwon S.U.,University of Ulsan | Kim J.S.,University of Ulsan
Frontiers of Neurology and Neuroscience | Year: 2016

Symptomatic cerebral atherosclerosis including intracranial atherosclerosis (ICAS) is associated with a high risk of recurrent stroke. Antithrombotic agents are the mainstay of therapy in these patients. Several studies have found anticoagulation (warfarin) to increase the risk of bleeding events and have an efficacy no better than that of aspirin. Therefore, anticoagulants are not widely used unless patients develop recurrent ischemic symptoms despite receiving antiplatelet therapy. Because ICAS progression is not uncommon and the risk of stroke recurrence is high when aspirin monotherapy is used, dual antiplatelet agents may be needed at least in the early disease stage. The Trial of Cilostazol in Symptomatic Intracranial Stenosis (TOSS) found that aspirin plus cilostazol was significantly better than aspirin monotherapy in preventing progression (6.7 vs. 28.8%, p = 0.008). The TOSS II trial that compared aspirin plus cilostazol with aspirin plus clopidogrel found no significant difference in the progression rate (9.3% vs. 15.5%, p = 0.092). However, the overall changes in stenosis were more favorable (i.e., less progression and more regression) in the cilostazol group (p = 0.049). TOSS studies have limitations in that the end points were changes in magnetic resonance angiography results rather than clinical outcomes. Based on the Clopidogrel in High-Risk Patients with Acute Nondisabling Cerebrovascular Events (CHANCE) trial results, and the fair outcome found in patients enrolled in the SAMMPRIS (Stenting versus Aggressive Medical Therapy for Intracranial Arterial Stenosis) trial, aspirin plus clopidogrel has been recommended in the early stage of symptomatic ICAS. However, the combination of aspirin and clopidogrel did not show superiority over aspirin monotherapy in ICAS patients in a recent CHANCE substudy. Considering that ICAS is the major pathology leading to stroke worldwide, further studies are needed to identify the best medication strategy in ICAS patients. Until then, physicians may choose appropriate antiplatelet agents after careful consideration of the characteristics of both the patients (i.e., degree of stenosis, stroke mechanism, risk of stroke, and risk of bleeding) and the antiplatelet agent (e.g., side effect, cost). © 2016 S. Karger AG, Basel. Copyright: All rights reserved.

Wong K.S.,Chinese University of Hong Kong | Caplan L.R.,Beth Israel Deaconess Medical Center | Kim J.S.,University of Ulsan
Frontiers of Neurology and Neuroscience | Year: 2016

Recent advances in neuroimaging technologies, such as diffusion weighted magnetic resonance imaging (MRI), perfusion weighted computed tomography (CT)/MRI, MR/CT angiography and Doppler ultrasonography allow us to determine the mechanisms of stroke and transient ischemic attack. In addition, high-resolution vessel wall MRI is nowadays increasingly used to understand the stroke mechanism in patients with intracranial atherosclerosis. Artery to artery embolism, hypoperfusion and the combination of the two are the important stroke mechanisms in patients with extracranial atherosclerosis. In addition to the above two, branch occlusion and in-situ thrombotic occlusion are important stroke mechanisms in patients with intracranial atherosclerosis. Branch occlusion leads to subcortical or brainstem infarcts indistinguishable from infarcts caused by small artery disease. In-situ thrombotic occlusion leads to larger territorial infarcts. However, whole territory infarcts are uncommon due to relatively well developed collateral circulation in these patients. The treatment strategy should be based on the correct understanding of the stroke mechanism in individual patients. © 2016 S. Karger AG, Basel.

Kim J.S.,University of Ulsan | Caplan L.R.,Beth Israel Deaconess Medical Center
Frontiers of Neurology and Neuroscience | Year: 2016

The main mechanism of stroke in patients who have extracranial atherosclerosis is artery to artery embolism, occasionally associated with hemodynamic disturbances. Although these mechanisms are also important in patients with intracranial atherosclerosis, branch occlusion and in-situ thrombotic occlusion play a relatively more important role in these patients. Accordingly, clinical stroke syndromes differ between extracranial atherosclerosis and intracranial atherosclerosis. In anterior circulation, middle cerebral artery atherosclerosis frequently produces subcortical infarction by way of branch occlusion. The clinical syndromes are similar to lacunar syndromes classically associated with small perforator artery diseases, although a larger size infarction can be accompanied by cortical dysfunction such as aphasia or neglect. In-situ thrombotic occlusion of the large intracranial anterior circulation arteries leads to larger infarction that results in cortical symptoms - however, parts of the cortex are usually spared due to relatively well developed collateral circulation associated with prolonged perfusion impairment. In the posterior circulation, intracranial atherosclerosis is common in the distal vertebral artery and basilar artery that often causes medullary and pontine infarction syndromes, mostly by way of branch occlusion. Posterior cerebral artery atherosclerosis produces pure midbrain or thalamic infarction through branch occlusion. Artery to artery embolisms from posterior fossa intracranial atherosclerosis lead to cortical infarction - cerebellar or temporo-occipital lobe infarction, producing ataxic syndromes, and visual field defects and associated neurobehavioral syndromes, respectively. © 2016 S. Karger AG, Basel. Copyright: All rights reserved.

Fujimura M.,Tohoku University | Bang O.Y.,Sungkyunkwan University | Kim J.S.,University of Ulsan
Frontiers of Neurology and Neuroscience | Year: 2016

Moyamoya disease (MMD) is a chronic occlusive cerebrovascular disease characterized by progressive stenosis at the terminal portion of the internal carotid artery and an abnormal vascular network at the base of the brain. Although its etiology is unknown, recent genetic studies have identified RNF213 in the 17q25-ter region as an important susceptibility gene of MMD among East Asian populations. A c.14576G>A polymorphism in RNF213 was identified in 95% of MMD patients with a family history and in 79% of sporadic cases, and patients carrying this polymorphism exhibited significantly earlier disease onset and a more-severe form of MMD. Due possibly to genetic differences, the prevalence of MMD is higher in East Asia (e.g., Korea and Japan) than in Western countries. The MMD prevalence peaks at two ages with different clinical presentations: around 10 years and at 30-45 years. Ischemic symptoms, including transient ischemic attacks, are the most important clinical manifestation in both children and adults. Intracranial hemorrhages are more frequent in adults than in children. Catheter angiography is a diagnostic method of choice. Magnetic resonance angiography and computed tomography angiography are noninvasive diagnostic methods. High-resolution vessel-wall magnetic resonance imaging also helps in diagnosing MMD by revealing concentric vessel-wall narrowing with basal collaterals. Surgical revascularization such as extracranial-intracranial bypass is the preferred procedure for MMD patients presenting with ischemic stroke. Surgical therapy may also be effective in patients with hemorrhages, based on recent observations in the Japan Adult Moyamoya trial. Procedure-related cerebral infarction and hyperperfusion syndrome are potential complications that can lead to neurological deterioration. © 2016 S. Karger AG, Basel. Copyright: All rights reserved.

Jung S.C.,University of Ulsan | Kang D.-W.,University of Ulsan | Turan T.N.,Medical University of South Carolina
Frontiers of Neurology and Neuroscience | Year: 2016

Angiography is a useful, important, common imaging method, with digital subtraction angiography (DSA) remaining the gold standard for luminal imaging. Computed tomography angiography (CTA) is minimally invasive and quite accurate in the evaluation of stenosis. Magnetic resonance angiography (MRA) is a good screening tool with the least invasiveness. Angiography mostly represents intracranial artery disease as luminal stenosis, which is often not sufficient to evaluate intracranial vascular pathology. The modalities provide indirect information about vascular pathology because luminal change, such as stenosis, results from the changes of vessel walls. Vessel wall imaging using high-resolution magnetic resonance imaging (HR-MRI) has been recently introduced for direct evaluation of vessel walls beyond just luminal information such as the severity of stenosis. HR-MRI for vessel walls can present the characteristic radiological findings for each intracranial artery disease such as atherosclerosis, dissection, moyamoya disease, and vasculitis. The radiological features are useful to differentiate among intracranial artery disease. This chapter discusses the role and radiological features of angiography and HR-MRI for vessel walls. © 2016 S. Karger AG, Basel. Copyright: All rights reserved.

Kim J.S.,University of Ulsan | Caplan L.R.,Beth Israel Deaconess Medical Center
Frontiers of Neurology and Neuroscience | Year: 2016

Atherosclerosis is not the only cause of intracranial arterial disease. Arterial dissection, moyamoya disease, vascular inflammatory disease, vasospasm and immunologic disorders are important non-atherosclerotic intracranial arterial diseases. Identification of the correct etiology is important in establishing treatment strategies and assessing prognosis. Careful history taking and appropriate laboratory testing are essential. Although catheter angiography is the most important diagnostic tool to examine various intracranial arterial diseases, other diagnostic modalities such as CT angiography and MR angiography are nowadays widely used. High resolution vessel wall MRI also can assist in making the correct diagnosis as this can yield information regarding vessel wall pathology. Certain diseases such as infectious vasculopathies and moyamoya disease are more prevalent in certain parts of the world, and physicians practicing in these regions should be mindful of these disorders. In this chapter, these non-atherosclerotic intracranial arterial diseases are discussed. Moyamoya disease will be described in another chapter. © 2016 S. Karger AG, Basel. Copyright: All rights reserved.

Dam D.-H.,University of Ulsan | Lee H.-H.,University of Ulsan
ECCE 2016 - IEEE Energy Conversion Congress and Exposition, Proceedings | Year: 2016

This paper proposed a distributed control method for dc microgrid to ensure the proportional load sharing by taking into account the different line impedance. In the proposed method, the operation point of each DG is effectively defined based on the power rating and the instantaneous power of the DG to achieve the proportional load power sharing. A low bandwidth communication is used to transmit the data required to determine the power reference for all DGs. In order to balance the power per unit requirement, the output voltage of each DG is controlled by a power controller to adjust the desired operating point. Therefore, all DGs can operate at the balanced operating point on the droop curve to ensure the proportional load power sharing. This paper also considers the load shedding to prevent the dc microgrid from operating under overload condition. The effectiveness of the proposed method is verified by simulation and experiment which are carried out with 2.8kW prototype dc microgrid. © 2016 IEEE.

Liem D.T.,University of Ulsan | Truong B.N.M.,HCMC Industry and Trade College | Ahn K.K.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

This study aims to develop an effective control approach for force control of a typical EHA system. This control scheme is considered as an advanced combination of a feedforward neural network - based PID (FNNPID) controller and a fuzzy grey predictor (FGP), shortened as feedforward neural network fuzzy grey predictor (FNNFGP). Here, the FNNPID controller is used to drive the system to desired targets. Meanwhile, the FGP predictor with self-tuning ability of the predictor step size takes part in, first, estimating the system output in the near future to optimize the controller parameters in advance and, second, creating a compensating control signal accordingly to the system perturbations and, consequently, improving the control performance. Real-time experiments have been carried out to investigate the effectiveness of the proposed control approach. © 2016 Institute of Control, Robotics and Systems - ICROS.

Hariyono J.,University of Ulsan | Kurnianggoro L.,University of Ulsan | Wahyono,University of Ulsan | Jo K.-H.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

The aim of this work is to improve driver awareness by proposing a collision risk analysis method. Pedestrian in the scene is observed by sequential frames from monocular camera mounted on the car. Positional information of object is extracted by projecting the centroid of bounding box on the ground plane. Four elements of collision criteria are constructed which are pedestrian walking direction, its velocity, car speed and relative distance of pedestrian. The analysis of collision risk is performed using fuzzy inference method that is used for calculating the degree of risk. Furthermore, localization of pedestrian is performed according to its risk score. The pedestrian with low collision score is labeled as low risk (green), pedestrian which is increasing its collision score is considered as medium risk (yellow) and pedestrian with high collision score is labelled as high risk (red). A quantitative analysis is performed by measuring effectiveness of this approach. The performance evaluation shows our proposed method achieved average accuracy 87.5% and it significantly outperforms human perception with more than 25% improvement. © 2016 Institute of Control, Robotics and Systems - ICROS.

Wahyono,University of Ulsan | Jo K.-H.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

In recent years, an intelligent surveillance system is widely developed along with the rapid use of closed circuit television (CCTV) camera in the public area. The system should be able to process multiple source data from different CCTV networks simultaneously and automatically detect any suspicious event on the monitoring area. A low-cost computational time is required to make a fast-enough system in order to prevent any delay in decision-making of the security officer. In this paper, multiple threading based process is proposed to achieve this requirement. In implementation, a four-channels intelligent surveillance system (ISS) is developed. Comparing to existing commercial systems, the ISS provides six surveillance tasks in ensuring a public safety such as unattended object detection, fire and smoke detection, human detection and tracking, sterile zone monitoring, and illegally parked vehicle detection. © 2016 Institute of Control, Robotics and Systems - ICROS.

Yu Y.-X.,University of Ulsan | Kwan A.K.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

Facing the energy crisis and environmental problems, saving energy of construction machinery, especially in the hydraulic excavator is very important. Regeneration of the potential energy is an effective solution to save energy. However, the conventional hybrid excavator can't regenerate the potential energy. This paper proposes a new structure of hydraulic excavator as well as a control strategy. The focus of the paper is using hydraulic transformer to regenerate energy. The simulation is carried out by the AMESim software. From the simulation results, this new system has a high efficiency for energy saving. © 2016 Institute of Control, Robotics and Systems - ICROS.

Ba D.X.,University of Ulsan | Ahn K.K.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

In this paper, an advanced controller is presented for position tracking control and minimizing control energy of an electro-hydraulic system. An index function is first formulated for the closed-loop performance. The optimal control input is then calculated based on the Taylor series expansion of the index function. For providing information to the control design, mathematical model of the EHS is also derived. Finally, effectiveness of the proposed controller is successfully validated through experimental results of different testing conditions. © 2016 Institute of Control, Robotics and Systems - ICROS.

Shahbaz A.,University of Ulsan | Kurnianggoro L.,University of Ulsan | Jo K.-H.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

Foreground detection is the classical computer vision task of segmenting out motion information from a particular scene. Foreground detection using Gaussian Mixture Models (GMM) is the famous choice. Since first time proposed, many researchers tried to improve GMM. This paper focuses on the comparative evaluation of three most famous improvements in the algorithm. The improved methods are compared both qualitatively and quantitatively using standard datasets available online. © 2016 Institute of Control, Robotics and Systems - ICROS.

Kurnianggoro L.,University of Ulsan | Shahbaz A.,University of Ulsan | Jo K.-H.,University of Ulsan
International Conference on Control, Automation and Systems | Year: 2016

This paper proposes a method for detecting moving objects appeared in video captured by a moving camera. The proposed method relies on dense optical flow to differentiate moving objects from static background. Whenever video taken from a static camera is used, the dense optical flow itself is sufficient to determine the moving object in the scenes. However, in a non-static camera, all pixels are moving making which lead to incapability of optical flow to differentiate the moving objects from the static background. In order to solve this problem, a stabilization method is incorporated by the mean of global motion extraction, which can be done by analyzing the homography transformation between two consequtive frames. Finally, by applying a threshold on the dense optical flow, the region of moving object is acquired. The proposed method has been evaluated in the experiments and produce satisfying results with 98% accuracy. © 2016 Institute of Control, Robotics and Systems - ICROS.

Islam Md.R.,The University of Asia Pacific | Islam M.M.M.,University of Ulsan | Kim J.-M.,University of Ulsan
Proceedings of 9th International Conference on Electrical and Computer Engineering, ICECE 2016 | Year: 2016

Features selection (FS) techniques have an apparent need in many complex engineering applications especially the bearing fault diagnosis of low-speed industrial motor. The main goal of an FS algorithm is to select the most discriminant features subset from a high-dimension features vector that increases the model performance by reducing the redundant and irrelevant fault features. This paper proposes an efficient fault diagnosis model of bearing by incorporating the optimal feature selection approach for increasing the reliability of fault diagnosis of bearing. Also, this paper investigates the feature selection approaches including sequential forward selection (SFS), sequential floating forward selection (SFFS), and genetic algorithm (GA) for identifying the most discriminant subset. The effectiveness of this discriminant features subset is verified with a low-speed bearing fault diagnosis application for identifying bearing failures. The experimental shows up-to-mark diagnosis performance using GA based optimal feature selection method. © 2016 IEEE.

Ngo C.T.,University of Ulsan | Oh H.,University of Ulsan | Yoo D.-S.,Electronics and Telecommunications Research Institute | Jang B.-T.,Electronics and Telecommunications Research Institute
FTC 2016 - Proceedings of Future Technologies Conference | Year: 2016

This paper presents an efficient and reliable protocol that enables a pipelined transmission using two channels in wireless sensor networks. Nodes in the network form a tree originating from a sink node. A sharable slot is allocated to each tree level and one unique channel is assigned to every other level in the tree. Data transmission is performed from the lowest level to the highest level, allowing two simultaneous transmissions. The level-order data transmission using a sharable slot also increases the reliability of data reception greatly because every node has multiple chances of receiving the same data while it reduces competition for data transmission. Using the simulator Cooja on Contiki OS, we showed that the proposed approach far outperformed the Deluge protocol in terms of completion time and control overhead. © 2016 IEEE.

Kim N.-K.,Medi Yin Hospital | Bin S.-I.,University of Ulsan | Kim J.-M.,University of Ulsan | Lee C.-R.,Inje University | Kim J.-H.,University of Ulsan
American Journal of Sports Medicine | Year: 2017

Background: Meniscal extrusion is related to degeneration of the native knee joint. However, the clinical effect of the phenomenon after meniscal allograft transplantation (MAT) has not been clearly identified. Purpose/Hypothesis: The purpose of this study was to evaluate the change in meniscal extrusion in both the coronal and sagittal planes after lateral MAT through the midterm follow-up period. We hypothesized that meniscal extrusion does not progress during the midterm follow-up period. Study Design: Case series; Level of evidence, 4. Methods: A total of 46 patients with a mean follow-up of 51.1 ± 7.1 months were included in the study. The patients underwent lateral MAT using the keyhole technique. Postoperative magnetic resonance imaging (MRI) was performed at 6-week, 1-year, and midterm (3- to 5-year) follow-up. In the coronal plane, the absolute value of meniscal subluxation and the relative percentage of extrusion (RPE) were measured. In the sagittal plane, meniscal subluxation was measured as the absolute and relative anterior cartilage meniscal distance (ACMD) and posterior cartilage meniscal distance (PCMD). The joint-space width (JSW) on weightbearing radiographs with 2 different knee positions was measured preoperatively and at 1-year and midterm follow-up. The Lysholm score was assessed at the same time points. Results: In the coronal plane, the mean absolute meniscal extrusion at 6-week, 1-year, and final follow-up was 2.90 ± 0.94, 2.85 ± 0.97, and 2.83 ± 0.89 mm, respectively, and the mean RPE was 27.0% ± 9.4%, 27.1% ± 10.1%, and 27.8% ± 9.7%, respectively. There were no statistically significant differences in absolute and relative coronal extrusion among the 3 time periods (P >.05). The percentage of patients with meniscal extrusion (≥3 mm) was 37.0% at 6-week follow-up and 34.8% at 1-year and final follow-up. In the sagittal plane, the mean absolute ACMD was 2.59 ± 1.75, 2.58 ± 1.85, and 2.37 ± 1.60 mm, respectively, and the mean relative ACMD was 20.7% ± 13.1%, 20.6% ± 13.8%, and 19.0% ± 12.2%, respectively, at the 3 follow-up time points. The mean absolute PCMD was -1.23 ± 3.34, -1.28 ± 3.08, and -1.42 ± 2.77 mm, respectively, and the mean relative PCMD was -10.3% ± 25.9%, -11.0% ± 24.6%, and -12.2% ± 23.2%, respectively, at the same time points. Sagittal extrusion was not significantly different between the time points (P >.05). The mean JSW at 2 days preoperatively, 1 year postoperatively, and midterm follow-up was 5.40 ± 1.07, 5.44 ± 1.04, and 5.43 ± 0.98 mm, respectively, on anterior-posterior radiographs with full extension, and it was 4.90 ± 0.94, 4.94 ± 0.98, and 4.89 ± 0.96 mm, respectively, on posterior-anterior radiographs with 45° of flexion. The mean JSW values were not significantly different between the 3 different time points (P >.05). The mean preoperative Lysholm score was 58. 9 ± 8.3; the score increased to 90.4 ± 9.7 at 1 year postoperatively and 90.5 ± 10.1 at final follow-up, which is a significant improvement compared with the preoperative status (P <.05). There was no statistically significant difference between the scores at the 2 postoperative time points (P >.05). Conclusion: This study demonstrated that extrusion of the meniscal allograft did not significantly progress either in the coronal or sagittal plane after lateral MAT during the midterm follow-up period. © 2016 The Author(s).

Tchah H.,University of Ulsan | Nam K.,Dongguk University | Yoo A.,Saevit Eye Hospital
International Journal of Ophthalmology | Year: 2017

Aim: To investigate the independent factors associated with photic phenomena in patients implanted with refractive, rotationally asymmetric, multifocal intraocular lenses (MIOLs). Methods: Thirty-four eyes of 34 patients who underwent unilateral cataract surgery, followed by implantation of rotationally asymmetric MIOLs were included. Distance and near visual acuity outcomes, intraocular aberrations, preferred reading distances, preoperative and postoperative refractive errors, mesopic and photopic pupil diameters, and the mesopic and photopic kappa angles were assessed. Patients were also administered a satisfaction survey. Photic phenomena were graded by questionnaire. Independent-related factors were identified by correlation and bivariate logistic regression analyses. Results: The distance from the photopic to the mesopic pupil center (pupil center shift) was significantly associated with glare/halo symptoms [odds ratio (OR)=2.065, 95% confidence interval (CI)=0.916-4.679, P=0.006] and night vision problems (OR=1.832, 95% CI=0.721-2.158, P=0.007). The preoperative photopic angle kappa was significantly associated with glare/halo symptoms (OR=2.155, 95% CI=1.065-4.362, P=0.041). The photopic angle kappa was also significantly associated with glare/halo symptoms (OR=2.155, 95% CI=1.065-4.362, P=0.041) and with night vision problems (OR=1.832, 95% CI=0.721-2.158, P=0.007) in patients implanted with rotationally asymmetric MIOLs. Conclusion: A large pupil center shift and misalignment between the visual and pupillary axis (angle kappa) may play a role in the occurrence of photic phenomena after implantation of rotationally asymmetric MIOLs. © 2017, International Journal of Ophthalmology (c/o Editorial Office). All rights reserved.

Park Y.-H.,Pusan National University | Chon M.-K.,Pusan National University | Lederman R.J.,U.S. National Institutes of Health | Sung S.-C.,Pusan National University | And 10 more authors.
JACC: Cardiovascular Interventions | Year: 2017

Objectives This is an early feasibility clinical test of mitral loop cerclage annuloplasty to treat secondary mitral valve regurgitation. Background Secondary mitral regurgitation is characterized by cardiomyopathy, mitral annular enlargement, and leaflet traction contributing to malcoaptation. Transcatheter mitral loop cerclage applies circumferential compression to the mitral annulus by creating a loop through the coronary sinus across the interventricular septum, protecting entrapped coronary arteries from compression, and interactive annular reduction under echocardiographic guidance. This is the first human test of mitral loop annuloplasty. Methods Five subjects with severe symptomatic secondary mitral regurgitation underwent mitral loop cerclage, with echocardiographic and computed tomography follow-up over 6 months. Results Mitral loop cerclage was successful in 4 of 5 subjects and aborted in 1 of the 5 because of unsuitable septal coronary vein anatomy. Immediately and over 6 months, measures of both mitral valve regurgitation (effective orifice area and regurgitation fraction) and chamber dimensions (left atrial and left ventricular volumes) were reduced progressively and ejection fractions increased. Two with persistent and permanent atrial fibrillation spontaneously reverted to sinus rhythm during follow-up. One subject experienced a small myocardial infarction from an unrecognized small branch coronary occlusion. Another, experiencing cardiogenic shock at baseline, died of intractable heart failure after 6 weeks. Conclusions In this first human test, mitral loop cerclage annuloplasty was successful in 4 of 5 attempts, caused reverse remodeling (reduction in secondary mitral regurgitation and heart chamber volumes), and suggested electrical remodeling (reversion of atrial fibrillation). Further evaluation is warranted. © 2017 American College of Cardiology Foundation

Kim Y.-J.,University of Ulsan | Min S.-Y.,Health Screening and Promotion Center | Lee D.H.,Chonnam National University | Lee B.K.,Chonnam National University | And 8 more authors.
JACC: Cardiovascular Interventions | Year: 2017

Objectives The authors aimed to evaluate the role of post-resuscitation electrocardiogram (ECG) in patients showing significant ST-segment changes on the initial ECG and to provide useful diagnostic indicators for physicians to determine in which out-of-hospital cardiac arrest (OHCA) patients brain computed tomography (CT) should be performed before emergency coronary angiography. Background The usefulness of immediate brain CT and ECG for all resuscitated patients with nontraumatic OHCA remains controversial. Methods Between January 2010 and December 2014, 1,088 consecutive adult nontraumatic patients with return of spontaneous circulation who visited the emergency department of 3 tertiary care hospitals were enrolled. After excluding 245 patients with obvious extracardiac causes, 200 patients were finally included. Results The patients were categorized into 2 groups: those with ST-segment changes with spontaneous subarachnoid hemorrhage (SAH) (n = 50) and those with OHCA of suspected cardiac origin group (n = 150). The combination of 4 ECG characteristics including narrow QRS (<120 ms), atrial fibrillation, prolonged QTc interval (≥460 ms), and ≥4 ST-segment depressions had a 66.0% sensitivity, 80.0% specificity, 52.4% positive predictive value, and 87.6% negative predictive value for predicting SAH. The area under the receiver-operating characteristic curves in the post-resuscitation ECG findings was 0.816 for SAH. Conclusions SAH was observed in a substantial number of OHCA survivors (25.0%) with significant ST-segment changes on post-resuscitation ECG. Resuscitated patients with narrow QRS complex and any 2 ECG findings of atrial fibrillation, QTc interval prolongation, or ≥4 ST-segment depressions may help identify patients who need brain CT as the next diagnostic work-up. © 2017 American College of Cardiology Foundation

Park J.,Catholic University of Daegu | Han B.-Y.,Yonsei University | Kim Y.,University of Ulsan
American Journal of Industrial Medicine | Year: 2017

Introduction: The present study examines gender differences in occupations, occupational hazards, and musculoskeletal symptoms in Korean workers. Methods: We performed a secondary analysis of data from the fourth Korean Working Conditions Survey (KWCS). Results: Relative to “managers,” men who were “craft and related trades workers,” “equipment, machine operating and assembling workers,” and in “elementary occupations” were more likely to report back pain (ORs: 2.08, 2.33, and 2.71, respectively); women who were “skilled agricultural, forestry, and fishery workers” were more likely to report back pain (OR: 3.96). Back pain was more likely to be reported in men exposed to “carrying/moving heavy loads,” “painful/tiring postures,” and “repetitive hand/arm movements” (ORs: 1.20, 2.26, and 1.28, respectively). Conclusion: Men and women workers differed in their reporting of ergonomic risk factors, and complaints of musculoskeletal symptoms. Am. J. Ind. Med. 60:342–349, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Kim J.H.,University of Ulsan | Kim S.H.,University of Ulsan | Oh Y.S.,University of Ulsan | Ihm H.J.,University of Ulsan | And 3 more authors.
Fertility and Sterility | Year: 2017

Objective To investigate the possible role of phthalate, a ubiquitous chemical used in consumer products, in the pathogenesis of uterine leiomyoma. Design Experimental and prospective case–control study using human samples. Setting University hospital. Patient(s) Fifty-three women with histologic evidence of uterine leiomyoma and 33 surgical controls without leiomyoma. Intervention(s) Human myometrial and leiomyoma cells were treated with di-(2-thylhexyl)-phthalate (DEHP). Main Outcome Measure(s) Cell viability assay and Western blot analyses after in vitro DEHP treatment; high-performance liquid chromatography electrospray ionization tandem mass spectrometry in cases and controls. Result(s) In vitro treatment with DEHP led to an increased viability and increased expressions of proliferating cell nuclear antigen, B-cell lymphoma 2 protein, and type I collagen in myometrial and leiomyoma cells. The urinary concentration of mono-(2-ethyl-5-carboxypentyl) phthalate was higher in women with leiomyoma compared with controls. Conclusion(s) These findings suggest that exposure to phthalate may play a role in the pathogenesis of uterine leiomyoma by enhancing proliferative activity, exerting an antiapoptotic effect, and increasing collagen contents in myometrial and leiomyoma cells. © 2017 American Society for Reproductive Medicine

Choi S.H.,Pusan National University | Lee H.,Elim Orthopedic Clinic | Cho J.H.,University of Ulsan | Jung J.I.,University of Ulsan | Lee D.-H.,University of Ulsan
CiOS Clinics in Orthopedic Surgery | Year: 2017

Background: Several scoring systems for cervical disc and facet joint degeneration, using radiography or computed tomography, have been developed and tested for reliability. However, definitions of disc height and facet joint space narrowing vary. To our knowledge, no study has reported quantitative data for normal radiologic values of the cervical spine in the Korean population. The purpose of this study is to determine normal cervical disc height, disc height ratio, and facet joint space values, and investigate the correlation between demographic data and these values. Methods: We performed a retrospective study of patients who underwent artificial disc replacement of the cervical spine. Disc heights and facet joint spaces were measured using cervical neutral lateral radiographs and computed tomography. The means, standard deviations, and 95% confidence intervals of the values were determined. Results: We measured 148 intervertebral discs and 352 posterior facet joints. The mean disc height measured by plain radiography and computed tomography was 5.57 ± 0.81 mm and 4.94 ± 0.94 mm, respectively. The mean facet joint space values measured by plain radiography and computed tomography were 1.94 ± 0.45 mm and 1.43 ± 0.39 mm, respectively. The disc heights and facet joint space values measured by plain radiography were greater than those measured by computed tomography. The lower limit of the 95% confidence interval of the disc height ratio calculated by plain radiography and computed tomography was greater than 0.94 at all levels except for C5–6. Patient height and disc height showed a tendency of positive correlation. Conclusions: In a Korean population, the normal cervical disc height was about 5.0 mm and the normal facet joint space was 1.4 mm. Disc height ratio can reliably identify normal cervical disc height in patients with mild degeneration. Patient height was positively correlated with disc height and facet joint space. Thus, when selecting a cervical implant, surgeons should consider patient height as well as estimated normal disc height. © 2017 by The Korean Orthopaedic Association.

Hoang T.V.,University of Ulsan | Nguyen T.D.,Ho Chi Minh City University of Technology | Lee H.-H.,University of Ulsan
IEEE International Conference on Sustainable Energy Technologies, ICSET | Year: 2017

This paper proposes an enhanced distributed generation (DG) unit with an adaptive virtual impedance control approach in order to solve the inaccurate reactive power sharing problem. The proposed method can adaptively regulate DG units with the aid of the equivalent impedance, and the mismatching problem of the feeder impedance is compensated by sharing the reactive power accurately. The proposed control strategy can be implemented directly without any pre-knowledge of the feeder impedances. Simulations are performed to validate the effectiveness of the proposed control approach. © 2016 IEEE.

Thanh Truc N.T.,University of Ulsan | Lee C.-H.,University of Ulsan | Lee B.-K.,University of Ulsan | Mallampati S.R.,University of Ulsan
Journal of Hazardous Materials | Year: 2017

Polyvinyl chloride (PVC) containing chlorine can release highly toxic materials and persistent organic pollutants if improperly disposed of. The combined technique of powder activated carbon (PAC) coating and mild heat treatment has been found to selectively change the surface hydrophobicity of PVC, enhancing its wettability and thereby promoting its separation from heavy plastic mixtures included polycarbonate (PC), polymethyl methacrylate (PMMA), polystyrene (PS) and acrylonitrile butadiene styrene (ABS) by means of froth flotation. The combined treatments helped to rearrange the surface components and make PVC more hydrophobic, while the remaining plastics became more hydrophilic. After the treatments at 150 °C for 80 s the contact angle of the PVC was greatly increased from 90.5 to 97.9°. The SEM and AFM reveal that the surface morphology and roughness changes on the PVC surface. XPS and FT-IR results further confirmed an increase of hydrophobic functional groups on the PVC surface. At the optimized froth flotation and subsequent mixing at 150 rpm, 100% of PVC was recovered from the remaining plastic mixture with 93.8% purity. The combined technique can provide a simple and effective method for the selective separation of PVC from heavy plastics mixtures to facilitate easy industrial recycling. © 2016 Elsevier B.V.

Choi G.-M.,KAIST | Jin J.,University of Ulsan | Shin D.,Korea Advanced Institute of Science and Technology | Kim Y.H.,Korea Advanced Institute of Science and Technology | And 5 more authors.
Advanced Materials | Year: 2017

A flexible hard coating for foldable displays is realized by the highly cross-linked siloxane hybrid using structure-property relationships in organic-inorganic hybridization. Glass-like wear resistance, plastic-like flexibility, and highly elastic resilience are demonstrated together with outstanding optical transparency. It provides a framework for the application of siloxane hybrids in protective hard coatings with high scratch resistance and flexibility for foldable displays. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Jung S.,Seattle Childrens Hospital Research Institute | Whiteaker J.R.,Fred Hutchison Cancer Research Center | Zhao L.,Fred Hutchison Cancer Research Center | Yoo H.-W.,University of Ulsan | And 3 more authors.
Journal of Proteome Research | Year: 2017

Wilson's Disease (WD), a copper transport disorder caused by a genetic defect in the ATP7B gene, has been a long time strong candidate for newborn screening (NBS), since early interventions can give better results by preventing irreversible neurological disability or liver cirrhosis. Several previous pilot studies measuring ceruloplasmin (CP) in infants or children showed that this marker alone was insufficient to meet the universal screening for WD. WD results from mutations that cause absent or markedly diminished levels of ATP7B. Therefore, ATP7B could serve as a marker for the screening of WD, if the protein can be detected from dried blood spots (DBS). This study demonstrates that the immuno-SRM platform can quantify ATP7B in DBS in the picomolar range, and that the assay readily distinguishes affected cases from normal controls (p < 0.0001). The assay precision was <10% CV, and the protein was stable for a week in DBS at room temperature. These promising proof-of-concept data open up the possibility of screening WD in newborns and the potential for a multiplexed assay for screening a variety of congenital disorders using proteins as biomarkers in DBS. © 2016 American Chemical Society.

Go H.,University of Ulsan | Shin S.,University of Ulsan | Kim Y.H.,University of Ulsan | Han D.J.,University of Ulsan | Cho Y.M.,University of Ulsan
Transplant International | Year: 2017

Chronic active/acute antibody-mediated rejection (cABMR) is the main cause of late renal allograft loss. Severe peritubular capillary basement membrane multilayering (PTCML) assessed on electron microscopy is one diagnostic feature of cABMR according to the Banff 2013 classification. We aimed to refine the PTCML criteria for an earlier diagnosis of cABMR. We retrospectively investigated ultrastructural features of 159 consecutive renal allografts and 44 nonallografts. The presence of serum donor-specific antibodies at the time of biopsy of allografts was also examined. Forty-three patients (27.0%) fulfilled the criteria of cABMR, regardless of PTCML, and comprised the cABMR group. Forty-one patients (25.8%) did not exhibit cABMR features and comprised the non-cABMR allograft control group. In addition, 15 zero-day wedge resections and 29 native kidney biopsies comprised the nonallograft control group. When the diagnostic accuracies of various PTCML features were assessed using the cABMR and non-cABMR allograft control groups, ≥4 PTCML, either circumferential or partial, in ≥2 peritubular capillaries of the three most affected capillaries exhibited the highest AUC value (0.885), greater than the Banff 2013 classification (0.640). None of the nonallograft control groups exhibited PTCML features. We suggest that ≥4 PTCML in ≥2 peritubular capillaries of the three most affected cortical capillaries represents the proper cutoff for cABMR. © 2017 Steunstichting ESOT

Kim H.S.,University of Ulsan | Goo D.-Y.,University of Ulsan | Woo S.K.,University of Ulsan
Tetrahedron | Year: 2017

An efficient one-step method to prepare aryl-substituted carbazoles via tandem double or triple C[sbnd]C bond formations by multiple Suzuki couplings and C[sbnd]N bond formation by Cadogan cyclization has been developed. The developed method employs commercially available or easily preparable polybromonitrobenzenes and arylboronic acids as starting materials, tolerates various functional groups, and provides good yields. © 2017 Elsevier Ltd

Im Y.-M.,Catholic University of Korea | Lee S.,Catholic University of Korea | Yun T.-J.,University of Ulsan | Choi J.Y.,Yonsei University
Cardiology in the Young | Year: 2017

Advancements in medical and surgical treatment have increased the life expectancy of patients with CHD. Many patients with CHD, however, struggle with the medical, psychosocial, and behavioural challenges as they transition from childhood to adulthood. Specifically, the environmental and lifestyle challenges in school are very important factors that affect children and adolescents with CHD. This study aimed to evaluate school-related adjustments depending on school level and disclosure of disease in children and adolescents with CHD. This was a descriptive and exploratory study with 205 children and adolescents, aged 7–18 years, who were recruited from two congenital heart clinics from 5 January to 27 February, 2015. Data were analysed using the Student’s t-test, analysis of variance, and a univariate general linear model. School-related adjustment scores were significantly different according to school level and disclosure of disease (p<0.001) when age, religion, experience being bullied, and parents’ educational levels were assigned as covariates. The school-related adjustment score of patients who did not disclose their disease dropped significantly in high school. This indicated that it is important for healthcare providers to plan developmentally appropriate educational transition programmes for middle-school students with CHD in order for students to prepare themselves before entering high school. © Cambridge University Press 2017

Kim Y.J.,University of Ulsan | Won C.H.,University of Ulsan | Chang S.E.,University of Ulsan | Lee M.W.,University of Ulsan | And 2 more authors.
Journal of the European Academy of Dermatology and Venereology | Year: 2017

Background: Recent studies have evaluated the expression of programmed death-1 (PD-1) and its prognostic value in malignant T-cell lymphomas. Objectives: This study investigated whether the positivity of PD-1 was associated with the clinical characteristics of cutaneous extranodal NK/T-cell lymphoma (ENKTL) and evaluated its effects on survival outcomes. Methods: Forty-one patients with cutaneous ENKTL were included. Clinical features and survival outcomes were analysed according to the positivity of PD-1. Results: There was no significant difference between primary cutaneous ENKTL and secondary cutaneous ENKTL in the expression of PD-1. The degree of disease dissemination was not affected by the positivity of PD-1. Higher positivity for PD-1 was associated with lesions presenting erythematous to purpuric patches that are mainly composed of small tumour cells. Cutaneous ENKTL presenting nodular lesions had a significantly lower number of PD-1-positive infiltrating cells than those with other clinical morphologies. There was no significant effect of PD-1 expression on outcomes such as overall and progression-free survival. Limitations: This study used a retrospective design and had a small sample size. Conclusion: Higher PD-1 positivity is associated with small-cell-predominant cutaneous ENKTL. However, PD-1 expression has no prognostic value in cutaneous ENKTL. © 2017 European Academy of Dermatology and Venereology.

Byeon S.-J.,University of Ulsan
Journal of Pathology and Translational Medicine | Year: 2017

Background: Pathologic examinations play an important role in medical services. Until recently, the overall status of pathologic examinations in Korea has not been identified. I conducted a nationwide survey of pathologic examination status using the insurance reimbursements (IRs) dataset from the Health Insurance Review and Assessment Service (HIRA). The aims of this study were to estimate current pathologic examination status in Korea and to provide information for future resource arrangement in the pathology area. Methods: I asked HIRA to provide data on IR requests, including pathologic examinations from 2011 to 2015. Pathologic examination status was investigated according to the following categories: annual statistics, requesting department, type of medical institution, administrative district, and location at which pathologic examinations were performed. Results: Histologic mapping, immunohistochemistry, and cervicovaginal examinations have increased in the last 5 years. Internal medicine, general surgery, obstetrics/gynecology, and urology were the most common medical departments requesting pathologic examinations. The majority of pathologic examinations were frequently performed in tertiary hospitals. About 60.3% of pathologic examinations were requested in medical institutions located in Seoul, Gyeonggi-do, and Busan. More than half of the biopsies and aspiration cytologic examinations were performed using outside services. The mean period between IR requests and 99 percentile IR request completion inspections was 6.2 months. Conclusions: This survey was based on the HIRA dataset, which is one of the largest medical datasets in Korea. The trends of some pathologic examinations were reflected in the policies and needs for detailed diagnosis. The numbers and proportions of pathologic examinations were correlated with the population and medical institutions of the area, as well as patient preference. These data will be helpful for future resource arrangement in the pathology area. © 2017 The Korean Society of Pathologists.

Kwon J.,University of Ulsan | Choi J.,Central Seoul Eye Center | Shin J.W.,University of Ulsan | Lee J.,University of Ulsan | Kook M.S.,University of Ulsan
Investigative Ophthalmology and Visual Science | Year: 2017

PURPOSE. To investigate whether the area and shape of the foveal avascular zone (FAZ) as assessed by optical coherence tomography angiography (OCTA) are altered in glaucomatous eyes with central visual field defects (CVFDs). METHODS. A total of 78 patients with open-angle glaucoma with central or peripheral visual field defects (PVFDs) confined to a single hemifield were studied retrospectively. Foveal avascular zone area and circularity were measured using OCTA images from the superficial retinal layer. Central retinal visual field (VF) sensitivity using Swedish Interactive Threshold Algorithm 24-2 VF and macular ganglion cell–inner plexiform layer (mGCIPL) thickness were measured. The FAZ area between VF-affected hemimacular segments and VF-unaffected hemimacular segments in eyes with CVFDs and matched hemimacular segments of eyes with PVFDs were compared. Factors associated with the presence and severity of CVFD at initial presentation were determined. RESULTS. Eyes with CVFDs showed a significantly larger FAZ area, lower FAZ circularity, and lower mGCIPL thickness than the PVFD group. The mean hemi-FAZ area of VF-affected hemimaculas in eyes with CVFDs was significantly larger than that of the PVFD group (0.256 6 0.07 mm2 vs. 0.184 6 0.07 mm2) and the VF-unaffected hemimaculas of the CVFD group (0.179 6 0.06 mm2; P < 0.05). Age, mean deviation, mGCIPL thickness, FAZ area, and circularity were associated with CVFDs (P < 0.05). CONCLUSIONS. Microcirculatory alterations in the perifovea are spatially correlated with central VF loss. Loss of FAZ circularity was significantly associated with presence of CVFD, whereas FAZ area was significantly associated with severity of CVFD. © 2017 The Authors.

Cho H.-Y.,Hallym University | Kim K.,Seoul National University | Kim Y.-B.,Seoul National University | Kim H.,University of Ulsan | No J.H.,Seoul National University
International Journal of Gynecological Cancer | Year: 2017

Objective: This study evaluated the expression patterns of nuclear factor erythroid 2-related factor 2 (Nrf2) and Kelch-like ECH-associated protein 1 (Keap1) and assessed their clinical value as prognostic indicators in ovarian cancer. Methods: The expression patterns of Nrf2 and Keap1 were determined in 100 epithelial ovarian cancers by immunohistochemistry analyses. The associations of Nrf2 and Keap1 expression with clinicopathological characteristics of patients were evaluated. All patients received platinum-based chemotherapy. Chemoresistance was defined as recurrence within 6 months of first-line chemotherapy. Results: Cytoplasmic expression of Nrf2 and Keap1 was observed in 95% and 72%, respectively, of all 100 epithelial ovarian cancers examined. Low Keap1 expression (intensity < 1) was strongly associated with disease recurrence (P = 0.046) and death (P = 0.002). Chemoresistance was associated with high Nrf2 expression (intensity = 3) (P = 0.833; hazard ratio [HR], 1.202; 95% confidence interval [CI], 0.217-6.667) and low Keap1 expression (P = 0.862; HR, 0.899; 95% CI, 0.270-2.994). However, these associations were not statistically significant. Survival analysis indicated that high Keap1 expression (intensity ≥ 1) was strongly predictive of better overall survival (P = 0.049) and disease-free survival (P = 0.004). Cox regression analysis indicated that Keap1 expression was an independent prognostic factor for overall survival (P = 0.012; HR, 0.349; 95% CI, 0.153-0.797). Although patients with high Nrf2 expression displayed better overall survival and disease-free survival, the association was not statistically significant. Conclusions: High cytoplasmic Keap1 expression, which might prevent nuclear translocation of Nrf2 in ovarian cancer cells, was associated with lower disease recurrence and death rate. Survival analysis suggested a probable role of Keap1 expression in predicting the prognosis of ovarian cancer. Copyright © 2017 by IGCS and ESGO.

In T.,Korea University | Jin Y.,Kaiser Rehabilitation Hospital | Jung K.,University of Ulsan | Cho H.-Y.,Gachon University
NeuroRehabilitation | Year: 2017

OBJECTIVES: The purpose of this study was to evaluate the effects of treadmill training with Thera-Band on motor function, gait and balance abilities in patients with stroke. METHODS: 30 participants with hemiparetic stroke were recruited and randomly divided into two groups: the experimental group (n=15) and the control group (n=15). Participants in both groups received conventional physical therapy for 30 minutes before the intervention. Additionally, subject in the experimental group performed treadmill training with Thera-Band for 30 minutes, five times a week for four weeks, while the control group conducted treadmill training only for the same amount of time. To measure motor function, Fugl-Meyer assessment (FMA) was used. Timed-up and Go (TUG), 10-meter walk test (10MWT) and Performance-oriented mobility assessment (POMA) were used to analysis balance and gait abilities. RESULTS: In FMA, TUG, 10MWT and Gait POMA, there were significant improvements in both groups after intervention. And more significant changes were shown in the experimental group than the control group (p<0.05). However, there was no significant difference within group and between the groups in the Balance POMA. CONCLUSIONS: Our findings indicate that treadmill training with Thera-Band is beneficial and effective to improve motor function of the lower extremities, gait and balance ability in stroke patients. © 2017 IOS Press and the authors. All rights reserved.

Park I.-N.,Inje University | Shim T.S.,University of Ulsan
Korean Journal of Internal Medicine | Year: 2017

Background/Aims: The usefulness of interferon-γ release assays (IGRAs) in monitoring to responses to anti-tuberculosis (TB) treatment is controversial. We compared the results of two IGRAs before and after anti-TB treatment in same patients with active TB. Methods: From a retrospective review, we selected patients with active TB who underwent repeated QuantiFERON-TB Gold (QFN-Gold, Cellestis Limited) and T-SPOT.TB (Oxford Immunotec) assays before and after anti-TB treatment with first-line drugs. Both tests were performed prior to the start of anti-TB treatment or within 1 week after the start of anti-TB treatment and after completion of treatment. Results: A total of 33 active TB patients were included in the study. On the QFN-Gold test, at baseline, 23 cases (70%) were early secreted antigenic target 6-kDa protein 6 (ESAT-6) or culture filtrate protein 10 (CFP-10) positive. On the T-SPOT. TB test, at baseline, 31 cases (94%) were ESAT-6 or CFP-10 positive. Most of patients remained both test-positive after anti-TB treatment. Although changes in interferon-γ release responses over time were highly variable in both tests, there was a mean decline of 27 and 24 spot-forming counts for ESAT-6 and CFP-10, respectively on the T-SPOT.TB test (p < 0.05 for all). Conclusions: Although limited by the small number of patients and a short-term follow-up, there was significant decline in the quantitative result of the T-SPOT. TB test with treatment. However, both commercial IGRAs may not provide evidence regarding the cure of disease in Korea, a country where the prevalence of TB is within the intermediate range. © 2017 The Korean Association of Internal Medicine.

Kim H.Y.,Jeju National University | Doh J.-H.,Inje University | Lim H.-S.,Ajou University | Nam C.-W.,Keimyung University | And 13 more authors.
JACC: Cardiovascular Interventions | Year: 2017

Objectives The authors sought to identify whether a coronary side branch (SB) is supplying a myocardial mass that may benefit from revascularization. Background The amount of subtending myocardium and physiological stenosis is frequently different between the main vessel (MV) and SB. Methods In this multicenter registry, 482 patients who underwent coronary computed tomography angiography and fractional flow reserve (FFR) measurement were enrolled. The % fractional myocardial mass (FMM), the ratio of vessel-specific myocardial mass to whole myocardium, was assessed in 5,860 MV or SB consisting of 2,930 bifurcations. Physiological stenosis was defined by fractional flow reserve (FFR) <0.80. Myocardial mass that may benefit from revascularization was defined by %FMM ≥10%. Results In per-bifurcation analysis, MV supplied a 1.5- to 9-fold larger myocardial mass compared with SB. Unlike left main bifurcation (n = 482), only 1 of every 5 non-left main SB (n = 2,448) supplied %FMM ≥10% (97% vs. 21%; p < 0.001). SB length ≥73 mm could estimate %FMM ≥10% (c-statistic = 0.85; p < 0.001). In 604 vessels interrogated by FFR, diameter stenosis was similar (p = NS), but %FMM ≥10%, FMM/minimal luminal diameter, and frequency of FFR <0.80 was higher in MV compared with SB (p < 0.001, all). Generalized estimating equations modeling demonstrate that vessel diameter, left myocardial mass, and FFR were not (p = NS), but SB length ≥73 mm and left main bifurcation were significant predictors for %FMM ≥10% (p < 0.001). Conclusions Compared with MV, SB supplies a smaller myocardial mass and showed less physiological severity despite similar stenosis severity. SB supplying a myocardial mass of %FMM≥10%, which may benefit revascularization could be identified by vessel length ≥73 mm. Pre-procedural recognition of these findings may guide optimal revascularization strategy for bifurcation. © 2017 American College of Cardiology Foundation

Kim P.H.,University of Ulsan | Tsauo J.,University of Ulsan | Shin J.H.,University of Ulsan | Yun S.-C.,University of Ulsan
Journal of Vascular and Interventional Radiology | Year: 2017

Purpose To evaluate the safety and efficacy of transcatheter arterial embolization with N-butyl cyanoacrylate (NBCA) for the treatment of gastrointestinal (GI) bleeding via a meta-analysis of published studies. Materials and Methods The MEDLINE/PubMed and EMBASE databases were searched for English-language studies from January 1990 to March 2016 that included patients with nonvariceal GI bleeding treated with transcatheter arterial embolization with NBCA with or without other embolic agents. The exclusion criteria were a sample size of < 5, no extractable data, or data included in subsequent articles or duplicate reports. Results The cases of 440 patients (mean age, 63.8 y ± 14.3; 319 men [72.5%] and 121 women [27.5%]) from 15 studies were evaluated. Of these patients, 261 (59.3%) had upper GI bleeding (UGIB) and 179 (40.7%) had lower GI bleeding (LGIB). Technical success was achieved in 99.2% of patients with UGIB (259 of 261) and 97.8% of those with LGIB (175 of 179). The pooled clinical success and major complication rates in the 259 patients with UGIB in whom technical success was achieved were 82.1% (95% confidence interval [CI], 73.0%–88.6%; P = 0.058; I2 = 42.7%) and 5.4% (95% CI, 2.8%–10.0%; P = 0.427; I2 = 0.0%), respectively, and those in the 175 patients with LGIB in whom technical success was achieved were 86.1% (95% CI, 79.9%–90.6%; P = 0.454; I2 = 0.0%) and 6.1% (95% CI, 3.1%–11.6%; P = 0.382; I2 = 4.4%), respectively. Conclusions Transcatheter arterial embolization with NBCA is safe and effective for the treatment of GI bleeding. © 2017 SIR

Park I.A.,University of Ulsan | Sa H.-S.,University of Ulsan | Chung Y.-S.,University of Ulsan | Cho K.-J.,University of Ulsan
American Journal of Ophthalmology Case Reports | Year: 2017

Purpose Primary ductal adenocarcinoma arising in the structures of the lacrimal apparatus is extremely rare, and the entity is considered a lacrimal counterpart of salivary duct carcinoma, of which the majority are known to express androgen receptor (AR). Less than 10 cases of AR-positive carcinomas of lacrimal gland or lacrimal sac have been described. Observations We present a primary ductal adenocarcinoma with AR expression involving the nasolacrimal duct of a middle-aged patient who had suffered from right eyelid swelling, diplopia and epiphora for 4 months. Although the tumor histologically resembled oncocytic carcinoma, electron microscopic examination did not show cytoplasmic accumulation of mitochondria, which excluded the diagnosis of oncocytic carcinoma with AR positivity. Conclusions and importance We concluded that this is the first case of AR-positive ductal adenocarcinoma arising from nasolacrimal duct. It is possible that some of the previously documented oncocytic carcinomas of the lacrimal drainage system may include ductal adenocarcinomas with oncocytic features. © 2016 The Authors

Kim Y.S.,University of Ulsan | Lee J.A.,University of Ulsan
Journal of the Korean Medical Association | Year: 2017

The Korean national health examination provides a tremendous amount of medical services in comparison with other countries. The first national health examination plan from 2011 to 2015 led to a remarkable growth in the number of examinees, the institutions that participate in the program, and financing for health examinations, and the national health examination will be expanded and reinforced through the upcoming second national health examination plan. Primary medical institutions should carry out health examinations related to chronic diseases, evaluate the lifestyles of examinees, counsel them about the results, and simultaneously offer follow-up management, so that the health examination and medical treatment function as parts of a cohesive continuum. For personalized health promotion integrated with information and communication technology, the health risk assessment program should be standardized in the Korean population. This will be a cost-effective strategy for managing overall health risks in comparison to the previous separate management of individual risk factors. Furthermore, whenever scientific evidence for items assessed in the national health examinations is lacking, the items should immediately be revised in accordance with appropriate validation studies, and quaternary prevention should be implemented in health examinations in order to avoid overdiagnosis and overtreatment. Finally, aid for vulnerable social classes should be expanded in order to improve the overall national health status and to address health inequalities. © copy Korean Medical Association.

Kim H.J.,University of Ulsan | Mun D.N.,University of Ulsan | Goo H.W.,University of Ulsan | Yun T.-J.,University of Ulsan
Korean Journal of Thoracic and Cardiovascular Surgery | Year: 2017

Background: Cardiac computed tomography (CT) has emerged as an alternative to magnetic resonance imaging (MRI) for ventricular volumetry. However, the clinical use of cardiac CT requires external validation. Methods: Both cardiac CT and MRI were performed prior to pulmonary valve implantation (PVI) in 11 patients (median age, 19 years) who had undergone total correction of tetralogy of Fallot during infancy. The simplified contouring method (MRI) and semiautomatic 3-dimensional region-growing method (CT) were used to measure ventricular volumes. Results: All volumetric indices measured by CT and MRI generally correlated well with each other, except for the left ventricular end-systolic volume index (LV-ESVI), which showed the following correlations with the other indices: the right ventricular end-diastolic volume index (RV-EDVI) (r=0.88, p < 0.001), the right ventricular end-systolic volume index (RV-ESVI) (r = 0.84, p = 0.001), the left ventricular end-diastolic volume index (LV-EDVI) (r = 0.90, p = 0.001), and the LV-ESVI (r = 0.55, p = 0.079). While the EDVIs measured by CT were significantly larger than those measured by MRI (median RV-EDVI: 197 mL/m2 vs. 175 mL/m2, p=0.008; median LV-EDVI: 94 mL/m2 vs. 92 mL/m2, p = 0.026), no significant differences were found for the RV-ESVI or LV-ESVI. Conclusion: The EDVIs measured by cardiac CT were greater than those measured by MRI, whereas the ESVIs measured by CT and MRI were comparable. The volumetric characteristics of these 2 diagnostic modalities should be taken into account when indications for late PVI after tetralogy of Fallot repair are assessed. © The Korean Society for Thoracic and Cardiovascular Surgery. 2017. All right reserved.

Kim J.C.,University of Ulsan | Kim J.C.,Institute of Innovative Cancer Research | Lee J.L.,University of Ulsan | Lee J.L.,Institute of Innovative Cancer Research | Park S.H.,University of Ulsan
Diseases of the Colon and Rectum | Year: 2017

BACKGROUND: Since the introduction of indocyanine green angiography more than 25 years ago, few studies have presented interpretative guidelines for indocyanine green fluorescent imaging. OBJECTIVE: We aimed to provide interpretative guidelines for indocyanine green fluorescent imaging through quantitative analysis and to suggest possible indications for indocyanine green fluorescent imaging during robot-assisted sphincter-saving operations. DESIGN: This is a retrospective observational study. SETTINGS: This study was conducted at a single center. PATIENTS: A cohort of 657 patients with rectal cancer who consecutively underwent curative robot-assisted sphincter-saving operations was enrolled between 2010 and 2016, including 310 patients with indocyanine green imaging (indocyanine green fluorescent imaging+ group) and 347 patients without indocyanine green imaging (indocyanine green fluorescent imaging-group). MAIN OUTCOME MEASURES: We tried to quantitatively define the indocyanine green fluorescent imaging findings based on perfusion (mesocolic and colic) time and perfusion intensity (5 grades) to provide probable indications. RESULTS: The anastomotic leakage rate was significantly lower in the indocyanine green fluorescent imaging+ group than in the indocyanine green fluorescent imaging-group (0.6% vs 5.2%) (OR, 0.123; 95% CI, 0.028-0.544; p = 0.006). Anastomotic stricture was closely correlated with anastomotic leakage (p = 0.002) and a short descending mesocolon (p = 0.003). Delayed perfusion (>60 s) and low perfusion intensity (1-2) were more frequently detected in patients with anastomotic stricture and marginal artery defects than in those without these factors (p ≤ 0.001). In addition, perfusion times greater than the mean were more frequently observed in patients aged >58 years, whereas low perfusion intensity was seen more in patients with short descending mesocolon and high ASA classes (≥3). LIMITATIONS: The 300 patients in the indocyanine green fluorescent imaging-group underwent operations 3 years before indocyanine green fluorescent imaging. CONCLUSIONS: Quantitative analysis of indocyanine green fluorescent imaging may help prevent anastomotic complications during robot-assisted sphincter-saving operations, and may be of particular value in high-class ASA patients, older patients, and patients with a short descending mesocolon. © 2016 The ASCRS.

Jang D.,University of Ulsan
Telemedicine journal and e-health : the official journal of the American Telemedicine Association | Year: 2015

OBJECTIVE: Managing test results is an important issue in hospitals because of the increasing use of point-of-care testing (POCT). Here, we propose a smartphone-based system for automatically managing POCT test results.MATERIALS AND METHODS: We developed the system to provide convenience to the medical staffs. The system recognizes the patient identification or prescription number of the test by reading barcodes and provides a countdown to indicate when the results will be ready. When the countdown in finished, a picture of the test result is transferred to the electronic medical record server using the Health Level 7 protocol. Human immunodeficiency virus (HIV) kits were selected in this research because HIV is a life-threatening infectious virus, especially for the medical staff who treat undiagnosed patients. The performance of the system was verified from a survey of the users.RESULTS: The performance of the system was tested at the emergency room (ER) for 10 months using commercially available POCT kits for detecting HIV. The survey showed that, in total, 80% and 0% of users reported positive or negative feedback, respectively. The staff also reported that the system reduced total processing time by approximately 32 min, in addition to reducing workload.CONCLUSIONS: The developed automated management system was successfully tested at an ER for 10 months. The survey results show that the system is effective and that medical staff members who used the system are satisfied with using the system at the ER.

Ko W.-S.,University of Ulsan | Ko W.-S.,Max Planck Institute Für Eisenforschung | Maisel S.B.,Max Planck Institute Für Eisenforschung | Grabowski B.,Max Planck Institute Für Eisenforschung | And 2 more authors.
Acta Materialia | Year: 2017

Molecular dynamics simulations are performed to investigate temperature- and stress-induced phase transformations in nanocrystalline nickel-titanium shape-memory alloys. Our results provide detailed insights into the origins of the experimentally reported characteristics of phase transformations at the nanoscale, such as the decrease of the transformation temperature with grain size and the disappearance of the plateau in the stress-strain response. The relevant atomic scale processes, such as nucleation, growth, and twinning are analyzed and explained. We suggest that a single, unified mechanism—dominated by the contribution of a local transformation strain—explains the characteristics of both temperature- and stress-induced phase transformations in nanocrystalline nickel-titanium. © 2016 Acta Materialia Inc.

Sharma A.,University of Ulsan | Lee B.-K.,University of Ulsan
Environmental Science: Nano | Year: 2017

An investigation is conducted into the emission reduction characteristics of atmospheric pollutants produced from an asphalt concrete (AC) mix using a Ca(OH)2-incorporated zeolite nanocomposite (Ca(OH)2@zeolite NC) synthesized as a recycling additive. As the synthesized additive was added into the AC mix, the water vapor produced from the thermal decomposition of Ca(OH)2@zeolite NC, even at low temperature, greatly reduced the asphalt viscosity and hence the emission of air pollutants such as volatile organic compounds (VOCs) and particulate matter (PM). The presence of water vapors in the feed suppressed the VOC adsorption capacity of zeolite due to the competitive adsorption of water vapors on the active sites. In addition, the enhanced catalytic activity of Ca(OH)2@zeolite was attributed to the synergistic catalysis between the super acidic and basic Brønsted sites of aldehydes and Lewis acid-base sites of Ca(OH)2@zeolite, which are the bridging OH groups in SiO4 4- and AlO2 -, due to thermal degradation of Ca(OH)2. The relatively less viscous asphalt is effectively mixed with coarse aggregates to coat or bind the particles, which greatly reduces the PM emissions compared to zeolite. Compared to the hot mix asphalt (HMA) with no additive at 180 °C, the addition of Ca(OH)2@zeolite NC at a concentration up to 6 wt% of the asphalt fraction into the warm mix asphalt (WMA) at 120 °C greatly reduced the atmospheric emissions (by 61-98% for VOCs, 52-92% for aldehydes, and 85% for PM2.5). The resulting large reduction of the working temperature during AC production and atmospheric emissions of hazardous chemicals will reduce workers' health risks. © The Royal Society of Chemistry.

Huynh X.-K.,Hanoi University of Science and Technology | Bae S.-W.,University of Ulsan | Kim J.S.,University of Ulsan
Journal of Korean Institute of Metals and Materials | Year: 2017

Fe-TiB2 powder was synthesized in-situ by the planetary ball milling and subsequent heat-treatment of an iron boride (FeB) and titanium hydride (TiH2) powder mixture. Mechanical activation of the (FeB+TiH2) powder mixtures was observed after a milling time of 3 hours at 700 rpm of rotation speed, but activation was not the same after 1 hour milling time. The particle size of the (FeB+TiH2) powder mixture was reduced to the nanometer scale, and each constituent was homogeneously distributed. A sharp exothermic peak was observed at a lower temperature (749°C) on the DSC curves for the (FeB+TiH2) powder mixture milled for 3 hours, compared to the one milled for 1 hour (774°C). These peaks were confirmed to have resulted from the formation reaction of the TiB2 phase, from Ti and B elements in the FeB. The Fe-TiB2 composite powder fabricated in situ exhibited only two phases of Fe and TiB2 with homogeneous distribution. The size of the TiB2 particulates in the Fe matrix was less than 5 nm. Copyright © The Korean Institute of Metals and Materials.

Pham T.-T.,University of Ulsan | Kang S.G.,University of Ulsan | Shin E.W.,University of Ulsan
Applied Surface Science | Year: 2017

In this study, molybdenum (Mo)-doped nickel titanate (NiTiO3) materials were successfully synthesized as a function of Mo content through a modified Pechini method followed by a solvothermal treatment process. Various characterization methods were employed to investigate the optical and structural properties of the materials. XRD patterns clearly showed that the NiTiO3 structure maintained a single phase with no observed crystalline structure transformations, even after the addition of 10 wt.% Mo. In the Raman spectra and XRD patterns, peak positions shifted with a change in Mo content, confirming that the NiTiO3 lattice was doped with Mo. On the other hand, Mo doping of NiTiO3 materials changed their optical properties. DRS-UV demonstrated that the addition of Mo increased photon absorption within the UV region. Relaxation processes were inhibited by Mo doping, which was evident in the PL spectra. Structural properties of the prepared materials were studied via FE-SEM and HR-TEM. The measured surface area increased proportionally with Mo content due to a reduction in grain size of the materials. © 2017 Elsevier B.V.

Ngo C.-V.,University of Ulsan | Chun D.-M.,University of Ulsan
Applied Surface Science | Year: 2017

Recently, the fabrication of superhydrophobic metallic surfaces by means of pulsed laser texturing has been developed. After laser texturing, samples are typically chemically coated or aged in ambient air for a relatively long time of several weeks to achieve superhydrophobicity. To accelerate the wettability transition from hydrophilicity to superhydrophobicity without the use of additional chemical treatment, a simple annealing post process has been developed. In the present work, grid patterns were first fabricated on stainless steel by a nanosecond pulsed laser, then an additional low-temperature annealing post process at 100 °C was applied. The effect of 100–500 μm step size of the textured grid upon the wettability transition time was also investigated. The proposed post process reduced the transition time from a couple of months to within several hours. All samples showed superhydrophobicity with contact angles greater than 160° and sliding angles smaller than 10° except samples with 500 μm step size, and could be applied in several potential applications such as self-cleaning and control of water adhesion. © 2017 Elsevier B.V.

Soltani T.,University of Ulsan | Kyu Lee B.,University of Ulsan
Journal of Colloid and Interface Science | Year: 2017

In this study, we report the synthesis of high purity reduced graphene oxide (rGO) from pristine graphite via a fast and cost-effective one-step ultrasonic reduction method. Ultrasonic treatment was employed to avoid the harsh reaction conditions, including high temperature and use of highly toxic hydrazine, required for the conventional rGO preparation method. The high temperature produced during the ultrasound irradiation at low temperature and short reaction time enabled the reduction of graphene oxide (GO) into rGO without the use of toxic chemicals. The oxygen functional groups on GO were successfully reduced by the sonochemical reduction. The rGO prepared using the ultrasonic method exhibited a curled morphology, a very thin wrinkled paper-like structure, sheet folding, minimal layers (∼4 layers), and a layer spacing of ∼1 nm. The sonochemical approach for the synthesis of rGO showed fast, high productivity, much improved safety, less energy, and time consuming characteristics as compared to other methods. More importantly, highly explosive and poisonous hydrazine is not required in this sonochemical technique, opposed to that required in conventional rGO synthesis, making it useful for many industrial applications of rGO. © 2016

Kim B.,City University of New York | Cho S.-B.,University of Ulsan
ISOCC 2016 - International SoC Design Conference: Smart SoC for Intelligent Things | Year: 2016

In this paper, we present a summary of 3D TSV inductors and their advances in RF applications. We describe a new inductor structure that uses fewer ground planes with the same functionality. Results were derived from a 3D full-wave simulation performed up to 2 GHz. © 2016 IEEE.

Kim H.-W.,Japan National Institute of Environmental Studies | Ohnishi S.,Japan National Institute of Environmental Studies | Fujii M.,Japan National Institute of Environmental Studies | Fujita T.,Japan National Institute of Environmental Studies | Park H.-S.,University of Ulsan
Journal of Industrial Ecology | Year: 2017

Industrial symbiosis (IS) exchanges have been recognized to reduce greenhouse gas (GHG) emission, though methods for quantification of GHG emissions in IS exchanges are varied, and no standardized methods are available. This article proposes a practical approach to quantify total and allocated GHG emissions from IS exchanges by integrating the GHG protocol and life cycle assessment. The proposed method expands the system boundaries to include all IS companies, and the functional flow is set to be the sum of the main products. The total impact of a company is allocated to the main product. Three by-product impact allocation methods of cutoff, avoidance, and 50/50 are proposed, and the total and distributed impacts of the IS systems in an industrial park are theoretically derived. The proposed method was tested to quantify GHG reduction in a real IS exchange developed between Korea Zinc (a zinc smelter) and Hankook Paper (a paper mill company) in the Ulsan Eco-Industrial Park initiative. The total reduction of GHG emissions in this IS exchange, 60,522 tonnes of carbon dioxide per year, was the same in the GHG protocol, whereas GHG distribution between two companies depended on the allocation method. Given that the reduction of GHG emissions from IS exchanges is the product of the collaboration of giving companies and receiving companies, the 50/50 allocation method is best from an equivalent-responsibility and benefit-sharing perspective. However, this study suggests a more practical implementation approach based on a flexible and negotiable method of allocating the total GHG reduction between stakeholders. © 2017, Yale University.

Rajagopalan B.,University of Ulsan | Kim B.,University of Ulsan | Hur S.H.,University of Ulsan | Chung J.S.,University of Ulsan
Surface and Coatings Technology | Year: 2017

This paper introduces a binder–free electrode prepared by a facile deposition of C/TiO2 (Carbon/TiO2) or C/GTiO2 (Carbon/Graphene–TiO2) on the coin cell anode using poly (methyl methacrylate) (PMMA) as a cheap carbon and binding source without using binders and a current collector. The use of graphene not only presents a conducting support to TiO2 particles, but also greatly improves the porosity of the electrode relative to pristine TiO2 or C/TiO2. In the lithium–ion battery (LIB) anode, the direct deposition enabled sufficient electrical conductivity of the electrode, the intercalated layer–by–layer (LBL) arrangement of the C/GTiO2 allowed sufficient Li+ accessibility, and the resulting electrode exhibited a higher specific capacity and an excellent rate capability compared to conventional TiO2 electrodes. Drop testing of the binder–free cells prior to electrochemical testing showed that all cells retained their original specific capacity, rate capability, and cycle stability, thus confirming the strong binding of the binder–free electrodes on the coin cell surface. © 2017 Elsevier B.V.

Cho Y.-K.,University of Ulsan | Kim J.-E.,University of Ulsan
Journal of Ginseng Research | Year: 2017

Background: Long-term ginseng intake can increase longevity in healthy individuals. Here, we examined if long-term treatment with Panax ginseng Meyer (Korean Red Ginseng, KRG) can also enhance survival duration (SD) in patients with human immunodeficiency virus type 1 (HIV-1) infection. Methods: We retrospectively analyzed 252 HIV-1 patients diagnosed from 1986 to 2013 prior to the initiation of antiretroviral therapy. Overall, 162 patients were treated with KRG (3,947. ±. 4,943 g) for 86. ±. 63 mo. The effects of KRG on SD were analyzed according to the KRG intake level and the length of the follow-up period. Results: There were significant correlations between the total amount of KRG and SD in the KRG intake group (r =0.64, p <0.0001) as well as between total amount of KRG and mean annual decrease in CD4+ T-cell count in all 252 patients (r =-0.17, p <0.01). The annual decrease in CD4+ T-cell count (change in cells/μL) was significantly slower in KRG-treated patients than in patients receiving no KRG (48±40 vs. 106±162; p <0.001). The SD (in months) was also significantly longer in the KRG group than in the no-KRG group (101±64 vs. 59±40, p <0.01). Conclusion: KRG prolongs survival in HIV-1 patients, possibly by slowing the decrease in CD4+ T-cell count. © 2017.

Lee J.G.,University of Ulsan | Lee G.-J.,Korea Atomic Energy Research Institute | Park J.-J.,Korea Atomic Energy Research Institute | Lee M.-K.,Korea Atomic Energy Research Institute
Journal of Nuclear Materials | Year: 2017

The compositional effects of ternary Zr-Cu-X (X: Al, Fe) amorphous filler alloys on galvanic corrosion susceptibility in high-temperature pressurized water were investigated for Zircaloy-4 brazed joints. Through an Al-induced microgalvanic reaction that deteriorated the overall nobility of the joint, application of the Zr-Cu-Al filler alloy caused galvanic coupling to develop readily between the Al-bearing joint and the Al-free base metal, finally leading to massive localized corrosion of the joint. Contrastingly, joints prepared with a Zr-Cu-Fe filler alloy showed excellent corrosion resistance comparable to that of the Zircaloy-4 base metal, since the Cu and Fe elements forming fine intermetallic particles with Zr did not influence the electrochemical stability of the resultant joints. The present results demonstrate that Fe is a more suitable alloying element than Al for brazing filler alloys subjected to high-temperature corrosive environments. © 2017 Elsevier B.V.

Tuan V.P.,University of Ulsan | Nguyen S.Q.,University of Ulsan | Kong H.Y.,University of Ulsan
International Conference on Advanced Technologies for Communications | Year: 2016

In this paper, we consider a decoded-And-forward (DF) energy-harvesting system with multiple antennas in the presence of transmit hardware impairments. The relays are energy-constrained nodes that collect energy from the source signals using time-switching architecture. Two partial relay selection (PRS) schemes that are PRS-1 and PRS-2 are employed for simplifying the relay-selection complexity. In particular, for the PRS-1 scheme, the best relay that assists the source-Todestination communication is selected based on the first-hop channel-state-information (CSI) whereas for the PRS-2 scheme, the best relay is selected based on the second-hop CSI. To evaluate the effects of hardware impairments on system performance, the analytical expressions for outage probability and throughput are derived. Monte Carlo simulation and insightful discussion are provided. © 2016 IEEE.

Minh N.N.,University of Ulsan | Kim M.K.,University of Ulsan
International Conference on Advanced Technologies for Communications | Year: 2016

In order to reduce the end-To-end delay in dutycycle MAC protocols of Wireless Sensor Networks (WSNs), the pipeline-forwarding technique has been proposed. According to this technique, sensor nodes along the forwarding path are scheduled with sequential wakeup time slots. Even though the previous pipeline-forwarding protocols such as P-MAC and PRIMAC showed a good result in term of reducing end-To-end delay, a significant per-hop delay is remained due to the unnecessary idle listening of sensor nodes in each cycle. In this paper, we propose a new pipeline-forwarding technique which tries to resolve this problem. In the proposed protocol, the RTS/CTS handshaking procedure is shortened by taking advantage of ACK mechanism. By waking up right before the upstream node sends ACK frame and overhearing it, a sensor node can be aware of the possibility of receiving data without waiting for and listening RTS frame. Therefore, the unnecessary idle listening can be reduced. When comparing with the existing solution PRI-MAC using QualNet simulator, our protocol shows the significant improvement in term of end-To-end delay and energy consumption. © 2016 IEEE.

Nguyen T.,University of Ulsan | Oh H.,University of Ulsan
ACM International Conference Proceeding Series | Year: 2016

This paper improves the Multi-Channel Slotted Sense Multiple Access (MC-SSMA) for a reliable data transmission in dynamic wireless sensor networks. In MC-SSMA, nodes form a tree originating from a sink. Then, only the nodes at the same tree level compete for data transmission. To improve throughput, the nodes at every other level use different channels so that they can transmit data packets in parallel. This approach suffers from collision since it employs CSMA for data transmission within a sharable slot and also shows the poor responsiveness to the change of topology. To reduce collision, a sharable slot is further divided into multiple mini-slots and the competing nodes are only allowed to transmit data at the boundary of mini-slot. To resolve the second problem, the mini-slot is further divided into two functional slots, control slot and data slot. All active nodes use a common control channel within the control slot so that a node moving to another level can still overhear control messages and find a new parent. Simulation results indicate that the proposed protocol far outperforms its ancestor MC-SSMA in the network scenario with fading model and node mobility. © 2016 ACM.

Wahyono,University of Ulsan | Jo K.-H.,University of Ulsan
Journal of Intelligent and Fuzzy Systems | Year: 2017

Detecting human carrying baggage from video sequences is one of the important modules in identifying unattended baggage for video surveillance system. Hence, this paper addresses a framework for implementing such module. As the video was recorded using a static camera, the background modeling is firstly constructed for extracting foreground regions. These regions are considered as candidate of human by further verifying them using a general human detector. To identify whether the human is carrying baggage or not, the human region is divided into several components such as head, body, leg and baggage components according to the spatial information of baggage relative to a human body proportion. The scalable histogram of oriented gradient features of each component are extracted and the feature dimension is reduced by applying genetic algorithm. The features are trained using a support vector machine (SVM) over each component regarded as a weak classifier. The boosting machine is employed to combine these weak classifiers into a strong classifier for final decision. In experiment, standard public dataset are used to evaluate the effectiveness of our proposed approach. The results verified that the proposed framework outperforms the state-of-the-art methods and can be considered as one of the solutions for aforementioned task. © 2017 - IOS Press and the authors. All rights reserved.

Park C.-H.,University of Ulsan | Kim H.-T.,University of Ulsan | Jang Y.-M.,University of Ulsan | Cho S.-B.,University of Ulsan
ISOCC 2016 - International SoC Design Conference: Smart SoC for Intelligent Things | Year: 2016

In this paper, in order to implement the IP of edge detection algorithm for surveillance in image using the camera in C'CTV or vehicle black box, we designed pre-processing step that is the edge extraction algorithm. First, after input image converts into die input signals of R, G, and B, three inputs are combined, and converted to gray scale. The data and blue color value are entered separated from each other and subtraction operations. Then appropriate portion by threshold extracts only white and converts the rest to black. A proposed algorithm was implemented using Matlab program It was verified through a RTL-level simulation of ISE14J. © 2016 IEEE.

Herein, we present scanning electron microscopy (SEM) correlated dark-field (DF) scattering studies of single gold nanorods (AuNRs). We demonstrate the effect of refractive index variation of the surrounding medium on the localized surface plasmon resonance (LSPR) linewidth in single AuNRs. The LSPR linewidth remains almost constant while increasing the dielectric constant of the medium, which is further verified by discrete dipole approximation (DDA) calculations. Furthermore, we demonstrate how thiol binding affects the LSPR linewidth of the longitudinal surface plasmon of single AuNRs. The thiol resulted in both a red shift and a strong damping with an increased LSPR linewidth. © 2017 Elsevier B.V.

Lee S.Y.,University of Ulsan | Kim G.W.,University of Ulsan | Ha J.W.,University of Ulsan
Chemical Physics Letters | Year: 2017

Herein, we employed single particle dark-field (DF) and differential interference contrast (DIC) microscopy to investigate the particle size dependency for large gold nanospheres (AuNSs) with average diameters of 100 nm, 300 nm, and 400 nm. Higher order plasmon resonances were observed in the single particle scattering spectra of large AuNSs (300 nm and 400 nm). Furthermore, the DF and DIC intensities were linearly increased with increasing the particle size from 100 nm to 400 nm. Therefore, the results provide useful experimental information of how the scattering and interference properties of single AuNSs are influenced by the particle size. © 2017 Elsevier B.V.

Lee B.S.,University of Ulsan | Jung E.,University of Ulsan | Lee Y.,University of Ulsan | Chung S.-H.,Kyung Hee University
Cell Stress and Chaperones | Year: 2017

Hypothermia (HT) is a well-established neuroprotective strategy against neonatal hypoxic ischemic encephalopathy (HIE). The overexpression of heat shock proteins (HSP) has been shown to provide neuroprotection in animal models of stroke. We aimed to investigate the effect of HT on HSP70 and HSP27 expression in a neonatal rat model of HIE. Seven-day-old rat pups were exposed to hypoxia for 90 min to establish the Rice-Vannucci model and were assigned to the following four groups: hypoxic injury (HI)-normothermia (NT, 36 °C), HI-HT (30 °C), sham-NT, and sham-HT. After temperature intervention for 24 h, the mRNA and protein expression of HSP70 and HSP27 were measured. The association between HSP expression and brain injury severity was also evaluated. The brain infarct size was significantly smaller in the HI-HT group than in the HI-NT group. The mRNA and protein expression of both HSPs were significantly greater in the two HI groups, compared to those in the two sham groups. Moreover, among the rat pups subjected to HI, HT significantly reduced the mRNA and protein expression of both HSPs. The mRNA expression level of the HSPs was proportional to the brain injury severity. Post-ischemic HT, i.e., a cold shock attenuated the expression of HSP70 and HSP27 in a neonatal rat model of HIE. Our study suggests that neither HSP70 nor HSP27 expression is involved in the neuroprotective mechanism through which prolonged HT protects against neonatal HIE. © 2017 Cell Stress Society International

Jung K.,Korea University | An J.M.,GINSENG BY PHARM Co. | Eom D.-W.,University of Ulsan | Kang K.S.,Gachon University | Kim S.-N.,Korea Institute of Science and Technology
Journal of Ginseng Research | Year: 2017

Background: Fermented black ginseng (FBG) is processed ginseng by the repeated heat treatment and fermentation of raw ginseng. The protective effect and mechanism of FBG on cisplatin-induced nephrotoxicity was investigated to evaluate its therapeutic potential. Methods: The free radical scavenging activity of FBG was measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH). In addition, the protective effect against cisplatin-induced renal damage was tested in rats. FBG was orally administered every day at a dose of 150 mg/kg body weight for 10 d, and a single dose of cisplatin was administered intraperitoneally (7.5 mg/kg body weight) with 0.9% saline on the 4th d. Results: The DPPH radical-scavenging activity of FBG (IC50 = 384 μg/mL) was stronger than that of raw ginseng. The improved DPPH radical-scavenging activity was mediated by the generation phenolic compounds. The decreased cell viability by cisplatin was recovered significantly after treatment with FBG in a dose-dependent manner. Then, the protective effect of FBG on cisplatin-induced oxidative renal damage was investigated in rats. The decreased creatinine clearance levels, which are a reliable marker for renal dysfunction in cisplatin-treated rats, were reduced to the normal level after the administration of FBG. Moreover, FBG showed protective effects against cisplatin-induced oxidative renal damage in rats through the inhibition of NF-κB/p65, COX-2, and caspase-3 activation. Conclusion: These results collectively show that the therapeutic evidence for FBG ameliorates the nephrotoxicity via regulating oxidative stress, inflammation, and apoptosis. © 2017 The Korean Society of Ginseng, Published by Elsevier Korea LLC.

Moon S.H.,Seoul Sacred Heart General Hospital | Lee J.I.,Seoul Sacred Heart General Hospital | Cho H.S.,University of Ulsan | Shin J.W.,University of Ulsan | Koh W.U.,University of Ulsan
Pain Research and Management | Year: 2017

Background. Lower back pain is a common reason for disability and the most common cause is lumbar disc herniation. Percutaneous epidural adhesiolysis has been applied to relieve pain and increase the functional capacity of patients who present this condition. Objectives. In this study, we retrospectively evaluated the factors which predict the outcome of percutaneous epidural adhesiolysis in patients who were diagnosed with lumbar disc herniation. Methods. Electronic medical records of patients diagnosed with lumbar disc herniation who have received percutaneous epidural adhesiolysis treatment were reviewed. Te primary outcome was the factors that were associated with substantial response of ≥4 points or ≥50% of pain relief in the numerical rating scale pain score 12 months afer the treatment. Results. Multivariate logistic regression analysis demonstrated that the presence of high-intensity zone (HIZ) at magnetic resonance imaging was a predictor of substantial response to percutaneous epidural adhesiolysis for 12 months (p = 0.007). Te presence of a condition involving the vertebral foramen was a predictor for unsuccessful response afer 12 months (p = 0.02). Discussion and Conclusion. Te presence of HIZ was a predictor of favorable long-term outcome afer percutaneous epidural adhesiolysis for the treatment of lower back pain with radicular pain caused by lumbar disc herniation. © 2017 Sang Ho Moon et al.

Chu S.J.,University of Ulsan | Lee Y.D.,University of Ulsan
Advanced Structured Materials | Year: 2017

A catalytic converter in the automotive exhaust system, consists of a substrate in the center, a mat outside the substrate and a can outside the mat. Since the substrate is brittle, it is wrapped in mats and press-fitted into a can. If the mat pressure developed during the canning process is excessive, it might cause the fracture of the substrate. A finite element program for finding mat pressures on the substrate in the canning process was developed in Microsoft EXCEL. It is a user-friendly program with easy input and graphical output. By modeling the substrate, the mat and the can as simply as possible, fixing the number of elements and iterations and taking into account only a small part of the output radial distance changes in the current step to calculate the input pressure in the next step, the material nonlinear problem was solved successfully in Microsoft EXCEL. The solutions were compared to ABAQUS solutions and found to be accurate. © Springer Science+Business Media Singapore 2017.

Alam M.W.,University of Ulsan | Yoo H.,University of Ulsan
Transactions of the Korean Institute of Electrical Engineers | Year: 2016

Magnetic resonance imaging has a potential to produce clear anatomical as well as functional images of human body. However, the ability to diagnose is limited by signal to noise ratio (SNR) and the resolution of current medical systems. To remove the challenges prevalent due to the use of high field scanners, dedicated radio frequency coils are used. Transverse electromagnetic coils have an advantage of providing homogeneous magnetic field throughout the region but with low signal to noise ratio while surface coils have an advantage of providing higher signal to noise ratio but with low homogeneity. This research combines both the advantage into one by utilizing transmit only transverse electromagnetic radio frequency coils (8 channel) along with receive only surface coils (by varying the number) for better imaging of brain. A 7 Tesla 32-channel close fitting helmet shaped phased-array surface coils along with the combination of 8 channel transmit only transverse electromagnetic coils provided good homogeneity as well as significant SNR improvements throughout the human brain. © The Korean Institute of Electrical Engineers.

Lee S.-H.,University of Ulsan | Park D.-J.,University of Ulsan | Yang W.-G.,University of Ulsan | Ryu K.-S.,University of Ulsan
Ionics | Year: 2017

Zn-air batteries have many advantages as energy devices but they show a poor charge-discharge cycle performance. Therefore, this study examined the effects of various types of electrolytes and conducting agents and changed the additive contents to optimize the electrochemical performance of Zn-air secondary batteries. Electrolytes, such as sodium hydroxide (NaOH) and potassium hydroxide (KOH) solutions, and conducting agents, such as super-p, denka black, acetylene black, and ketjen black, were used to increase the electric conductivity. The electrochemical performance of the zinc anode was evaluated from charge-discharge capacities and cycle efficiency. When the capacity was compared according to each electrolyte from one to ten cycles, in contrast, the zinc anode in 6 M KOH showed a higher discharge capacity in the first cycle. Therefore, zinc anode was composed in the 6-M KOH electrolyte and conducting agents were added. The zinc anode included conducting agents with a higher cycle capacity than those without conducting agents, and super-p had a higher first discharge capacity than the others. Therefore, the zinc anode with super-p of 4% shows the highest performance using 6 M KOH in Zn-air secondary batteries. © 2017 Springer-Verlag Berlin Heidelberg

Thuyet-Nguyen M.,University of Ulsan | Hai-Nguyen H.,University of Ulsan | Kim W.J.,University of Ulsan | Kim H.Y.,University of Ulsan | Kim J.-C.,University of Ulsan
Metals and Materials International | Year: 2017

Nanomaterials have attracted great attention from chemists, physicists and materials scientists because of their application benefits and special properties. Thermoplastics have been used in many applications such as molding of non-electrical components, conducting, magnetic field and 3D printing. Nanocomposites are known as a material which blends the best properties of components, a high performance material exhibits unusual property combinations and unique design possibilities. In this research, we focused to investigate and report primary results in the synthesis of magnetic nanocomposites based on acrylonitrile butadiene styrene (ABS), which are useful and important thermoplastics. Nickel nanopowder was prepared by electrical explosion of wire in a liquid were used as magnetic component. The composites were prepared by following steps, first the obtained Ni nanopowders were incorporated into the ABS matrix via a solution blending method (drop-casting), and then the solvent was evaporated. The characterizations of obtaining composites were analyzed by field emission scanning electron microscopy, X-Ray Diffraction analysis and vibrating sample magnetometer. © 2017, The Korean Institute of Metals and Materials and Springer Science+Business Media Dordrecht.

Maruthamuthu M.K.,University of Ulsan | Selvamani V.,University of Ulsan | Eom G.T.,Korea Research Institute of Chemical Technology | Eom G.T.,Korea University | Hong S.H.,University of Ulsan
Biochemical Engineering Journal | Year: 2017

Bisphenol-A (BPA)-sensing and adsorption recombinant Escherichia coli were constructed based on the recA promoter. Quantitative, real-time PCR was carried out to analyze the expression profile of the ompC gene in response to various concentrations of BPA. The results show that this system senses BPA from 50 ppb to a maximum concentration of 40 ppm. The adsorption system based on the cell surface display fused with a BPA binding peptide can absorb 354.0 μmol/g cell DCW at 180 ppm of BPA. The strains used in the study show high selectivity towards BPA adsorption and sensing, and this novel system could thus be employed for sensing and adsorption in BPA contaminated environments, such as in thermal paper wastewater industry and other BPA leached water. © 2017 Elsevier B.V.

Rajagopalan B.,University of Ulsan | Kim B.,University of Ulsan | Hur S.H.,University of Ulsan | Yoo I.-K.,University of Ulsan | Chung J.S.,University of Ulsan
Journal of Alloys and Compounds | Year: 2017

Poly (p–phenylenediamine)–reduced graphene oxide/lithium titanate (PpPDA–RGO)/Li4Ti5O12 (PG/LTO) nanocomposites were prepared by a simple one–step synthesis procedure using the redox reactions of a graphene oxide/LTO (GO/LTO) suspension and p–phenylenediamine (pPDA). The effect of pPDA on both the reduction of GO and the electrochemical performance in a lithium battery anode was systematically evaluated at different pPDA loadings. The rate capabilities of the PG/LTO nanocomposites were found to be superior to those of both GO/LTO and pristine LTO. Optimum electrochemical performance was ultimately obtained with a pPDA:GO ratio of 3:1. The use of pPDA increased the reduction of GO/LTO and ensured good contact between the RGO and LTO, thereby increasing the electrical conductivity of the nanocomposites. © 2017 Elsevier B.V.

Kim B.,Ulsan National Institute of Science and Technology | Baek S.-M.,Ulsan National Institute of Science and Technology | Lee J.G.,University of Ulsan | Park S.S.,Ulsan National Institute of Science and Technology
Journal of Alloys and Compounds | Year: 2017

The microstructure and tensile properties of Mg–6Zn–0.5Zr alloy processed by low-temperature indirect extrusion utilizing artificial cooling were investigated. Remarkable grain refinement was obtained by the application of artificial cooling, resulting in an increase in the yield strength of as much as 53 MPa at room temperature, as compared to the case (245 MPa) of indirect extrusion without artificial cooling. Besides this, the fine-grained alloy was found to have superplastic properties at elevated temperature, revealing tensile elongations of 720–810% at 200 °C at strain rates of 2 × 10−4–1 × 10−3 s−1. Mechanisms responsible for the high strength and superplastic properties are discussed. © 2017 Elsevier B.V.

Soltani T.,University of Ulsan | Lee B.-K.,University of Ulsan
Chemical Engineering Journal | Year: 2017

Three metal doped BiFeO3 magnetic nanoparticles (BFO MNPs), namely Bi1−xBaxFeO3 (x = 0.03), BiFe1−yCuyO3 (y = 0.1) and Bi1−xBaxFe1−yCuyO3 (x = 0.03, y = 0.1), were successfully prepared by a novel and simple sol-gel method. Then, iron and iron-copper heterogeneous Fenton-like photocatalysts were applied to activate H2O2 to hydroxyl radicals (OH) and persulfate (S2O8 2−) to sulfate radical anions (SO4 −) for enhanced degradation of 2-chlorophenol (2-CP) from aqueous solution. Both Fe3+/Fe2+ and Cu+/Cu2+ pairs in the BFO MNPs systems effectively decomposed H2O2 to OH and S2O8 2− to SO4 −. After only 70 min of visible light irradiation, Cu-doped BFO (BiFe1−yCuyO3) and Ba-Cu co-doped BFO (Bi1−xBaxFe1−yCuyO3) almost completely degraded 2-CP with reductions in total organic carbon (TOC) of 68 and 73%, respectively, which were much higher than that achieved with BFO and Ba-doped BFO, due to the formation of OH in the Cu2+/Fe2+/H2O2/visible light couple. However, 2-CP was completely degraded with Cu-doped BFO and Ba-Cu co-doped BFO in less than 30 min, due to the effective formation of SO4 − in the Cu2+/Fe2+/S2O8 2−/visible light couple. Cu2+ or Fe2+ ions in H2O2/visible light or S2O8 2−/visible light couples are important species in the improved degradation of 2-CP in the photo-Fenton catalytic reaction. However, the photo-Fenton catalytic degradation of 2-CP was greatly reduced in the absence of any species of Cu2+ or Fe2+ ions, H2O2, S2O8 2−, and visible light irradiation. © 2016 Elsevier B.V.

Ba Hung N.,University of Ulsan | Jaewon S.,University of Ulsan | Lim O.,University of Ulsan
Applied Energy | Year: 2017

In order to develop a high performance electric bicycle, a simulation study of its dynamic characteristics and required power is conducted based on the effects of various input parameters such as rider mass, bicycle mass, wind speed, crank length, wheel diameter, and grade. Operation of the electric bicycle is modeled and simulated based on mathematical models including bicycle dynamics under human power only and bicycle dynamics with the assistance of an electric motor. In addition, a simulation model for consumed power when propelling the electric bicycle is also established. MATLAB/SIMULINK is used as a solver to calculate the dynamics and required power of the electric bicycle. Based on the required power obtained from this simulation, a suitable power is selected for the motor of the electric bicycle. In addition, a model-based control study is conducted with the aim of controlling the speed of the electric bicycle under the effects of slope grade. Finally, to support the presented simulations, an experimental study is conducted to examine operating characteristics of the electric bicycle in two cases: under human power only and human power with the assistance of an electric motor. Experimental data is acquired using the LabVIEW programming framework. The experimental results are compared with simulation results to validate the presented simulations. © 2017 Elsevier Ltd.

Choi Y.-R.,University of Ulsan
Quarterly Journal of Mechanics and Applied Mathematics | Year: 2016

This study investigates the extensibility of an air-inflated, heavy membrane structure. Based on the linear stress-strain relation, the membrane tube section is modelled mathematically while considering the self-weight and extensibility of the membrane material. The governing equations are expressed in a non-dimensional form, in which the extensibility factor is introduced. Integration of these governing equations results in simultaneous algebraic equations of unknowns at the boundaries. These unknowns can be found iteratively using the solutions from the inextensible problem as an initial guess. Some numerical examples are presented to discuss the effect of the extensibility. © The Author, 2016. Published by Oxford University Press; all rights reserved.

Herein, the authors consider harvested energy powered cognitive radio networks (CRNs) in which harvested energy is stored in a rechargeable battery which has finite capacity. In addition, a practical scenario in which the amount of harvested power is finite is taken into account. Cognitive users (CUs) opportunistically access a licensed channel (or primary channel); meanwhile, it should be ensured that their confidential communications are not leaked to an eavesdropper. We investigate an optimal spectrum sensing schedule and the optimal amount of transmission energy for the CUs in each processing time slot. In particular, at the beginning of each time slot, based on the remaining energy in the battery, CU transmitter decides either: 1) to be active to sense the channel and transmit its data if the channel is found vacant or 2) to stay inactive during the current time slot in order to save energy and wait for more incoming energy for use in the next time slots. The decision is based on expected secrecy transmission rate calculated for both cases over subsequent K time slots. The proposed scheme aims to improve long-term secrecy transmission rate of CRNs in comparison with a conventional scheme where the decision for the current time slot is made to maximize current secrecy transmission rate without considering any future reward. © 2017 IEEE.

Koo B.-U.,University of Ulsan | Yi Y.,University of Ulsan | Lee M.,University of Ulsan | Kim B.-K.,University of Ulsan
Metals and Materials International | Year: 2017

With increased hydrogen consumption in ammonia production, refining and synthesis, fuel cells and vehicle industries, development of the material components related to hydrogen production is becoming an important factor in industry growth. Porous metals for fabrication of hydrogen are commonly known for their relative excellence in terms of large area, lightness, lower heat capacity, high toughness, and permeability. Fe-Cr-Al alloys not only have high corrosion resistance, heat resistance, and chemical stability but also ductility, excellent mechanical properties. In order to control powder size and sintering temperature effects of Fe-Cr-Al porous metal fabrication, Fe-Cr-Al powder was classified into 25-35 μm, 35-45 μm, 45-75 μm using an auto shaking sieve machine and then classified Fe-Cr-Al powders were pressed into disk shapes using a uniaxial press machine and CIP. The pelletized Fe-Cr-Al specimens were sintered at various temperatures in high vacuum. Properties such as pore size, porosity, and air permeability were evaluated using perm-porosimetry. Microstructure and phase changes were observed with SEM and XRD. Porosity and relative density were proportionated to increasing sintering temperature. With sufficient sintering at increasing temperatures, the pore size is expected to be gradually reduced. Porosity decreased with increasing sintering temperature and gradually increased necking of the powder. © 2017, The Korean Institute of Metals and Materials and Springer Science+Business Media Dordrecht.

Duong H.T.,University of Ulsan | Suh Y.S.,University of Ulsan
IEEE Sensors Journal | Year: 2017

This paper presents an algorithm for estimating walking parameters (step length, step speed, and walking distance) using a wrist-mounted inertial measurement unit for those who use a front-wheeled walker. Two walking styles are considered: step-by-step walking and continuous walking. A new zero-velocity detection algorithm is proposed for when the user walks step by step. Then, a standard inertial navigation algorithm is applied using a Kalman filter and zero-velocity update. For continuous walking, a step detection algorithm is proposed based on the bio-mechanical relationship between arm and foot movements. A step length estimation model was derived by testing 128 different features. The accuracy of walking parameters estimation was verified through 20-m walking experiments with five subjects. © 2017 IEEE.

Pham T.-D.,University of Ulsan | Lee B.-K.,University of Ulsan
Chemical Engineering Journal | Year: 2017

In this study, Ag and V co-doped TiO2 deposited on polyurethane (Ag@V-TiO2/PU) was for novel photocatalytic removal of gaseous volatile organic compounds (VOCs). The combination of V doping, which enhanced internal electron transfer in the TiO2 lattice, and Ag doping, which exhibited high internal electron transfer in the Ag2O and enhanced exterior electron transfer among Ag particles, Ag2O and TiO2, increased the photocatalytic activity of Ag@V-TiO2/PU for the removal of VOCs in aerosol. The surface area of this co-doped photocatalyst was also higher than that of the undoped and single-dopant photocatalysts. The optimal combination of weight ratios of Ag/TiO2 and V/TiO2 for maximizing the surface area and photocatalytic activity of TiO2 was 4 and 2%, respectively. Under visible light, the removal efficiency of individual hexane and butyl acetate gas by 4Ag@2V-TiO2/PU was 93.7 and 95.5%, respectively. The removed hexane and butyl acetate were mineralized into CO2 with ratios of 93.2 and 96.2%, respectively. The individual removal of hexane and butyl acetate gas by Ag@V-TiO2/PU was similar; however, in the mixture stream of both VOCs, much more butyl acetate than hexane was photocatalytically removed. This was associated with the much higher polarity of butyl acetate than that of hexane, so that the photocatalyst surface, where most of the oxy radicals were generated to oxidize the VOCs, was more occupied or covered by butyl acetate than by hexane. © 2016 Elsevier B.V.

Jung D.-W.,University of Ulsan | Jeong J.-H.,University of Ulsan | Oh E.-S.,University of Ulsan
Journal of Alloys and Compounds | Year: 2017

Here, the electrochemical properties of layered-structure KFeO2 anode material for lithium-ion batteries (LIBs) are reported for the first time in the literature. The even-sized KFeO2 compounds were synthesized by the thermal diffusion of potassium into Fe2O3 nanoparticles produced using high temperature calcination of a graphene substrate. With the help of potassium, unlike typical iron oxide electrodes, the redox conversion between Fe0 and Fe2+/Fe3+ in the KFeO2 electrode became gradually decreased, whereas the interfacial charging/discharging of lithium ions through the layered-structure increased as charge/discharge was repeated. In addition, the continuous cycle led to potassium desertion from KFeO2 phases, forming well-dispersed layered-structure Fe2O3 nanoparticles less than 2 nm throughout the electrode. Such a favorable scenario gave rise to a significant reversible capacity of 2564 mAh g−1 after 1000 cycles at an extremely high current rate of 18.56 A g−1. © 2016 Elsevier B.V.

Yi K.-S.,Pusan National University | Kim H.-J.,Pusan National University | Kim H.-J.,University of Ulsan
Journal of Physics Condensed Matter | Year: 2017

We investigate spectral behavior of phonon spectral functions in an interacting multi-component hot carrier plasma. Spectral analysis of various phonon spectral functions is performed considering carrier-phonon channels of polar and nonpolar optical phonons, acoustic deformation-potential, and piezoelectric Coulomb couplings. Effects of phonon self-energy corrections are examined at finite temperature within a random phase approximation extended to include the effects of dynamic screening, plasmon-phonon coupling, and local-field corrections of the plasma species. We provide numerical data for the case of a photo-generated electron-hole plasma formed in a wurtzite GaN. Our result shows the clear significance of the multiplicity of the plasma species in the phonon spectral functions of a multi-component plasma giving rise to a variety of spectral behaviors of carrier-phonon coupled collective modes. A useful sum rule on the plasma-species-resolved dielectric functions is also found. © 2016 IOP Publishing Ltd.

Kalashnyk N.,Aix - Marseille University | Mouhat K.,Aix - Marseille University | Oh J.,University of Ulsan | Jung J.,University of Ulsan | And 6 more authors.
Nature Communications | Year: 2017

In the blooming field of on-surface synthesis, molecular building blocks are designed to self-assemble and covalently couple directly on a well-defined surface, thus allowing the exploration of unusual reaction pathways and the production of specific compounds in mild conditions. Here we report on the creation of functionalized organic nanoribbons on the Ag(110) surface. C-H bond activation and homo-coupling of the precursors is achieved upon thermal activation. The anisotropic substrate acts as an efficient template fostering the alignment of the nanoribbons, up to the full monolayer regime. The length of the nanoribbons can be sequentially increased by controlling the annealing temperature, from dimers to a maximum length of about 10 nm, limited by epitaxial stress. The different structures are characterized by room-temperature scanning tunnelling microscopy. Distinct signatures of the covalent coupling are measured with high-resolution electron energy loss spectroscopy, as supported by density functional theory calculations. © 2017 The Author(s).

Yang H.S.,Seoul Shinsegae Eye Center | Woo J.E.,University of Ulsan | Kim M.-H.,University of Ulsan | Kim D.Y.,Korea University | Yoon Y.H.,University of Ulsan
PLoS ONE | Year: 2017

We investigated the relationship between the peripapillary retinal nerve fiber layer and peripapillary retinal thickness in patients with diabetic macular edema. Fifty eyes (group I) with non-proliferative diabetic retinopathy and diabetic macular edema receiving intravitreal anti-VEGF injection, and 90 eyes (group II) without diabetic macular edema were included in this case-control study. The peripapillary retinal nerve fiber layer thickness, peripapillary retinal thickness, and a new retinal nerve fiber layer index using a modeled relationship between the two parameters were evaluated with spectral-domain optical coherence tomography, at baseline and at the 6-month follow-up. In group I, the peripapillary retinal nerve fiber layer thickness decreased from 126.4 μm at baseline to 117.6 μm at 6 months (p < 0.001), while the peripapillary retinal thickness decreased from 376.0 μm at baseline to 359.6 μm at 6 months (p < 0.001) after intravitreal anti-VEGF injection. In group II, however, both the parameters remained stable at the 6-month follow-up (100.7 to 102.1 μm and 311.1 to 316.2 μm, respectively, and all p > 0.01). Analysis with the new index to adjust for retinal edema showed no significant change from baseline to 6 months in both groups (p = 0.593 and p = 0.101, respectively). The peripapillary retinal nerve fiber layer thickness is strongly affected by the peripapillary retinal thickness. Therefore, the measured changes in peripapillary retinal nerve fiber layer thickness may not represent the real gain or loss of the retinal nerve fiber layer. Therefore, the new retinal nerve fiber layer index, which corrects for the component of macula edema, could be a better means of assessing the changes of peripapillary retinal nerve fiber layer thickness in patients with diabetic macular edema. © 2017 Yang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Kim G.W.,University of Ulsan | Lee S.Y.,University of Ulsan | Ha J.W.,University of Ulsan
Analyst | Year: 2017

Bimetallic core-shell gold nanorods (AuNRs) are promising multifunctional orientation probes that can be employed in biological and physical studies. This paper presents the optical properties of single AuNRs coated with palladium (Pd) and platinum (Pt) under scattering-based dark-field (DF) microscopy. Strong longitudinal plasmon damping was observed for the bimetallic AuNRs due to Pd and Pt metals on the AuNR surface. Despite the strong plasmon damping, the bimetallic AuNRs yielded characteristic doughnut-shaped scattering patterns under defocused DF microscopy. Interestingly, a solid bright spot appeared at the center of the defocused scattering patterns due to strong damping in the longitudinal plasmon and the increased contribution from the transverse dipoles to the image patterns, which was verified further by a simulation study. Furthermore, the defocused scattering field distributions enabled a determination of the three-dimensional (3D) orientations of single bimetallic AuNRs through a pattern-match analysis technique without angular degeneracy. Therefore, deeper insight into the optical properties and defocused scattering patterns of single bimetallic AuNRs is provided, which can be used to develop multifunctional optical probes that are capable of sensing of the 3D orientation of a probe, biomolecules based on LSPR shift, gas and humidity, etc. This journal is © The Royal Society of Chemistry.

Pham T.-D.,University of Ulsan | Lee B.-K.,University of Ulsan
Applied Catalysis A: General | Year: 2017

In this study, Ag and Cu co-doped TiO2 deposited on polyurethane (Ag@Cu-TiO2/PU) was synthesized for the conversion of CO2 into solar fuels under visible light. The synthesized Ag@Cu-TiO2/PU, which synergistically inherited all the advantages of both Ag and Cu doping, exhibited very high photocatalytic activity for the reduction of gaseous CO2 to produce CH4 and CO fuels. The dopants defects in the TiO2 lattice formed Ti3+ and oxygen vacancies in the lattice. The presence of Ti3+ and oxygen vacancies on the surface of the photocatalyst induced the formation of new adsorption sites to adsorb CO2. The Ag and Cu dopants also enhanced the separation of electron–hole pairs of the doped TiO2 photocatalysts. Therefore, the Ag@Cu- TiO2/PU photocatalysts generated electron–hole pairs, which could react with H2O and CO2 to produce the CO and CH4, even under visible light. 2Ag@4Cu-TiO2/PU, corresponding to the Ag/TiO2 and Cu/TiO2 ratios of 2 and 4 wt%, respectively, exhibited the highest photocatalytic reduction of CO2. The yields of CH4 and CO produced from the photocatalytic reduction of CO2 by 2Ag@4Cu-TiO2/PU under visible light were 880 and 550 (μmol/g.cat), respectively. © 2016 Elsevier B.V.

Kim J.C.,University of Ulsan | Lee J.L.,University of Ulsan | Alotaibi A.M.,University of Ulsan | Yoon Y.S.,University of Ulsan | And 2 more authors.
International Journal of Colorectal Disease | Year: 2017

Purpose: Few investigations of robot-assisted intersphincteric resection (ISR) are presently available to support this procedure as a safe and efficient procedure. We aimed to evaluate the utility of robot-assisted ISR by comparison between ISR and abdominoperineal resection (APR) using both robot-assisted and open approaches. Methods: The 558 patients with lower rectal cancer (LRC) who underwent curative operation was enrolled between July 2010 and June 2015 to perform either by robot-assisted (ISR vs. APR = 310 vs. 34) or open approaches (144 vs. 70). Perioperative and functional outcomes including urogenital and anorectal dysfunctions were measured. Recurrence and survival were examined in 216 patients in which >3 years had elapsed after the operation. Results: The robot-assisted approach was the most significant parameter to determine ISR achievement among potent parameters (OR = 3.467, 95% CI = 2.095–5.738, p < 0.001). Early surgical complications occurred more frequently in the open ISR group (16 vs. 7.7%, p = 0.01). The voiding and male sexual dysfunctions were significantly more frequent in the open ISR (p < 0.05). The fecal incontinence and lifestyle alteration score was greater in the open ISR than in the robot-assisted ISR at 12 and 24 months, respectively (p < 0.05). However, the 3-year cumulative rates of local recurrence and survival did not differ between the two groups. Conclusions: The current procedure of robot-assisted ISR replaced a significant portion of APR to achieve successful SSO via mostly transabdominal approach and double-stapled anastomosis. The robot-assisted ISR with minimal invasiveness might be a help to reduce anorectal and urogenital dysfunctions. © 2017 Springer-Verlag Berlin Heidelberg

Kwon T.,University of Ulsan | Park S.,University of Ulsan | Moon K.H.,University of Ulsan
International Urology and Nephrology | Year: 2017

Purpose: To investigate the effect of metabolic syndrome (MS) on patient outcomes who underwent holmium laser enucleation of the prostate (HoLEP) for benign prostatic obstruction. Materials and methods: Data from 151 patients who underwent HoLEP by a single surgeon between March 2012 and March 2016 were retrospectively analyzed. Patients with MS were assigned to group 1 (n = 33) and patients without MS in group 2 (n = 118). Clinical characteristics and the International Prostate Symptom Score (IPSS), including quality of life (QoL), peak urinary flow rate (Qmax), and postvoid residual urine (PVR), before surgery and 3 months afterward were compared between groups. Additionally, predictors of total IPSS improvement after HoLEP were assessed. Results: Compared with group 2 patients, group 1 patients were older (70.3 vs. 65.2 years old, p = 0.001). Preoperative data, which included prostate volume, QoL, Qmax, and PVR, were not different between groups. For all patients, both the storage subscore and voiding subscore significantly decreased after surgery (p < 0.001). Postoperative total IPSS and voiding subscore improvement in group 1 were lower than in group 2 (total IPSS improvement 9.2 vs. 12.5, p = 0.042; voiding subscore improvement 6.6 vs. 8.8, p = 0.048). Multivariate analysis showed preoperative total IPSS (β = 0.79, CI 0.71–0.94, p < 0.001) and number of MS components (β = −0.15, CI −2.04 to −0.29, p = 0.009) were independently associated with total IPSS improvement. Conclusions: We found that MS was associated with decreased postoperative symptom improvement. Thus, lower urinary tract symptoms after surgery may be a systemic disorder due to multiple metabolic risk factors. © 2017 Springer Science+Business Media Dordrecht

Choi J.W.,University of Ulsan | Suh Y.C.,University of Ulsan | Song S.Y.,University of Ulsan | Jeong W.S.,University of Ulsan
Aesthetic Plastic Surgery | Year: 2017

Background: Regarding septal fixation in nasal tip plasty, the nasal tip tripod theory may require modification. We performed three-dimensional (3D) photogrammetric analysis of the “Skiff graft,” which is a quadripod method involving folded conchal cartilages fixated on the caudal septal angle, paired lateral crura reinforced by a derotational conchal cartilage graft, and conjoined medial crus on the columella base. We assessed the efficacy of the Skiff graft in maintaining tip projection and preventing cephalic rotation of the nasal tip. Methods: In total, 39 patients who underwent nasal tip plasty with the Skiff graft during 2012–2015 and underwent 3D photogrammetry before (T0), immediately postoperatively (T1, average of 1 week postoperatively), and an average of 215 days postoperatively (T2) were included. Nasal tip projection was objectively measured from images using a software program. Results: The average differences between the T0 and T1, T0 and T2, and T1 and T2 lengths were 4.81, 3.57, and 0.85 mm, respectively. Thus, 81% of the change in tip projection length that had been achieved immediately postoperatively was maintained at T2 based on 3D photogrammetry (P < 0.001). The relapse ratio of the examined technique was 19.26% (mean, 0.85 mm; P < 0.001). Conclusions: Nasal tip plasty with the Skiff graft preserves septal support and is an effective primary and revision rhinoplasty technique in Asian patients. This approach may be suitable as an alternative to nasal tip plasty with the septal extension graft in terms of maintaining nasal tip projection, rotational controllability, and nasal mobility. Level of Evidence IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. © 2017 Springer Science+Business Media New York and International Society of Aesthetic Plastic Surgery

Kim H.,University of Ulsan | Lee S.H.,University of Ulsan | Kim B.J.,University of Ulsan | Koh J.M.,University of Ulsan
Osteoporosis International | Year: 2017

Summary: Indicators of total and abdominal obesity were negatively associated with femoral neck strength indices. There are age-, sex-, and fat distribution-specific differences in the magnitude of these associations. These suggested that indicators of obesity with different magnitude according to age, sex, and fat distribution associated with poor bone health. Introduction: Fat regulates bone metabolism, but the associations of total and abdominal obesity with bone health are inconsistent. We investigated the association between indicators of obesity and composite indices of femoral neck (FN) strength reflecting the risk of hip fracture. Methods: This population-based cross-sectional study examined data from the Korea National Health and Nutrition Examination Surveys. Participants were divided into groups according to age (25–49/≥50 years) and sex. We examined total fat mass (TFM) and percentage fat mass (pFM) as indicators of total obesity and truncal fat mass (TrFM) as an indicator of abdominal obesity. We calculated the composite indices of FN strength and anthropometric clinical indicators of abdominal obesity. Results: TFM, pFM, and TrFM were negatively associated with the composite indices, irrespective of age and sex (P < 0.001–0.005). Most anthropometric clinical indicators of abdominal obesity showed negative associations with the composite indices regardless of age and sex (P < 0.001–0.048), except for women aged 25–49 years. In men, magnitudes of the negative contributions of TFM to the composite indices were significantly stronger at age 25–49 years than at age ≥50 years. Magnitudes of negative associations of TFM with the composite indices were greater in men than in women. TrFM had a more detrimental effect than TFM on FN strength in men aged 25–49 years and in women of both ages. Conclusion: Indicators of total and abdominal obesity negatively associated with FN strength, and magnitudes of their effects on bone health differed according to age, sex, and fat distribution. © 2017 International Osteoporosis Foundation and National Osteoporosis Foundation

Yang D.H.,University of Ulsan | Kim Y.-H.,University of Ulsan
International Journal of Cardiovascular Imaging | Year: 2017

Computed tomography myocardial perfusion (CTP) combined with coronary computed tomography angiography (CCTA) may constitute a “1-stop shop” for the noninvasive diagnosis of hemodynamically significant coronary stenosis during a single CT examination. CTP shows high diagnostic performance and provides incremental value over CCTA for the detection of hemodynamically significant coronary stenosis in patients with a high Agatston calcium score or coronary artery stents. Future studies should determine the optimal protocol and clinical value of CTP for guiding revascularization strategy and prognostication. In this article, we review the current status and future perspectives of CTP, focusing on technical considerations, clinical applications, and future research topics. © 2017 Springer Science+Business Media Dordrecht

Bang J.H.,University of Ulsan | Park J.-J.,University of Ulsan | Goo H.W.,University of Ulsan
Pediatric Radiology | Year: 2017

Background: There are limited data regarding the influence of commissural malalignment of the aortic-pulmonary sinus on the arterial switch operation. Objective: To compare diagnostic accuracy between cardiac CT and echocardiography for evaluating commissural malalignment of aortic-pulmonary sinus in children with complete transposition of the great arteries and to seek potential clinical implication of commissural malalignment on the arterial switch operation. Materials and methods: In 37 patients (35 boys; median age: 8 days, range: 3-80 days) with complete transposition of the great arteries who had tricuspid semilunar valves and underwent an arterial switch operation, the degree of the commissural rotation of the aortic-pulmonary sinus was assessed on cardiac CT (n=37) and echocardiography (n=35). With surgical finding as a reference, cardiac CT was compared with echocardiography in identifying commissural malalignment in 35 patients. The influence of the height difference between the semilunar valves measured by cardiac CT on the identification of commissural malalignment with cardiac CT and echocardiography was evaluated. The impact of commissural malalignment on coronary transfer techniques was evaluated. Results: In operative findings, the commissures of the semilunar valves were aligned in 24 patients and malaligned in 13. With surgical findings as a reference, cardiac CT showed higher, but not statistically significant (P>0.05), sensitivity (91.7% vs. 75.0%), specificity (87.0% vs. 78.3%) and accuracy (88.6% vs. 77.1%) for the diagnosis of the malalignment than echocardiography. The measured height difference between the semilunar valves did not affect the identification of the malalignment with cardiac CT and echocardiography. The surgical malalignment group showed a higher requirement of modified coronary transfer techniques than the surgical aligned group (11/13 vs. 11/24, P=0.03). Conclusion: Cardiac CT and echocardiography appear useful for evaluating commissural malalignment of the semilunar valves in patients with complete transposition of the great arteries frequently requiring modified coronary transfer techniques at during an arterial switch operation. © 2017 Springer-Verlag Berlin Heidelberg

Choe J.,University of Ulsan | Lee S.M.,University of Ulsan | Lim S.,University of Ulsan | Choi S.H.,University of Ulsan | And 3 more authors.
European Radiology | Year: 2017

Objectives: We retrospectively evaluated the doubling time (DT) of thymic epithelial tumours (TET) according to the histological subtype on CT. Methods: From January 2005 to June 2016, we enrolled 53 patients who had pathologically confirmed TET and at least two CT scans. Tumour size was measured using a two-dimensional method, and the DT was calculated. DTs were compared among histological subtypes, and factors associated with rapid tumour growth (DT <180 days) were assessed. Results: In 42 of the 53 patients (79.2%) the tumours showed interval growth (>2 mm) during follow-up. The median DT for all tumours was 400 days (range 48–1,964 days). There were no significant differences in DT in relation to histological subtype (p = 0.177). When TETs were recategorized into three groups, i.e. low-risk thymomas (types A, AB, B1), high-risk thymomas (types B2, B3), and thymic carcinoma, DT was significantly different among the groups (median DT 436, 381 and 189 days, respectively; p = 0.031). Histological subtype (type B3 and thymic carcinoma) was the single independent predictor of rapid tumour growth. Conclusions: The majority of TETs grew during follow-up with variable and relatively slow growth rates. Histological features of aggressive behaviour significantly correlated with a decreased DT and rapid growth. Key points: • The majority of thymic epithelial tumours grew during follow-up (79.2%, 42/53). • Doubling times of thymic epithelial tumours were highly variable (median 400 days). • Histological features of aggressive behaviour significantly correlated with a decreased doubling time. © 2017 European Society of Radiology

Van Nghia N.,University of Ulsan | Park S.,KAIST | An Y.,University of Ulsan | Lee J.,Chonnam National University | And 3 more authors.
Journal of Materials Chemistry C | Year: 2017

A series of iridium(iii) cyclometalates with mono-, bis-, and tris-o-carboranyl ligands, fac-[m-(2-MeCB)ppy]nIr(ppy)3−n (n = 1-3, m = 5 (3a-5a); m = 4 (3b-5b); 2-MeCB = 2-methyl-o-carboran-1-yl; ppy = 2-phenylpyridinato-C2,N), was prepared to investigate the impact of the number of o-carboranyl ligands on the photophysical and electroluminescent properties. X-ray diffraction analysis of 3b-5b revealed that the carboranyl C-C bond distances remained nearly unchanged with different numbers of carboranyl ligands. While the phosphorescence wavelengths of 3a-5a and 3b-5b were blue-shifted or red-shifted with respect to that of fac-Ir(ppy)3 (6), respectively, both series underwent gradual hypsochromic shifts as the number of carboranyl ligands was increased. All of the complexes exhibited moderate to high phosphorescence quantum efficiencies in toluene with a slightly higher efficiency for the 5-substituted 3a-5a (ΦPL = 0.43-0.98) than for the 4-substituted 3b-5b (ΦPL = 0.42-0.92). In particular, the quantum efficiency increased as the number of carboranyl ligands increased. Solution-processed green phosphorescent organic light-emitting diodes (PhOLEDs) incorporating the 5-substituted complexes (3a-5a) as emitters exhibited a similar level of high performance, of which the best performance was observed for devices based on 4a. Furthermore, vacuum-deposited devices were successfully fabricated with heteroleptic mono- and bis-carboranyl complexes, 3a and 4a. The resulting devices showed excellent performance, which was improved by ca. 40% compared to those of the solution-processed devices. The devices based on 4a also displayed a performance that was superior to those of the devices based on 3a (max. CE = 45.8 cd A−1; PE = 35.4 lm W−1; EQE = 15.1% for 4a at 7 wt% Ir). © The Royal Society of Chemistry.

Iftekhar Uddin A.S.M.,University of Ulsan | Chung G.-S.,University of Ulsan
Microelectronic Engineering | Year: 2017

In this work, low-temperature and flexible self-powered active acetylene (C2H2) gas sensing has been realized from the piezo-plasmonic properties of Ag@ZnO nanowire (NW) arrays through visible light modulation. With the assistance of 3.48-21.47mWcm-2 visible light illumination, the piezoelectric output of the Ag@ZnO NW arrays acting as a response signal shows significant improvement over the traditional resistive-type C2H2 sensor at room temperature. Photoexcited plasmonic Ag nanoparticles (NPs) favorably modifies the intrinsic properties and increases the carrier density in the sensing surface, resulting in a strong piezoelectric screening effect. Under 12.72mWcm-2 visible light intensity (under 1.3Hz and 6N compressive forces), the sensor shows a sensitivity up to 51.7% at 1000ppm acetylene at room temperature, whereas at 90°C the sensor shows a maximum response up to 83.86%. Under the same condition, an average response time of 87s is observed (upto 1000ppm gas concentration) as well as a broad detection range of 25-1000ppm and excellent selectivity. The current results demonstrate a feasible approach for developing light modulated, low-temperature self-powered active gas sensors and their potential in smart wearable, handheld, and portable applications. © 2017 Elsevier B.V.

Islam M.S.,University of Ulsan | Cho S.,University of Ulsan | Chong U.,University of Ulsan
IETE Technical Review (Institution of Electronics and Telecommunication Engineers, India) | Year: 2016

This paper presents a constant speed rotating machines fault analysis method to maximize incipient fault signatures based on computed order tracking with adaptive filter and cyclic logarithmic envelope spectrum (CLES) tools. First, adaptive filter reduces not-concerned harmonic components and measurement artefacts from a vibration signal. To accurately and precisely select the step size in the process of the LMS-type adaptive filter, a new method is proposed based on wavelet entropy (WE). Then, a tacho signal is generated from vibration signal and computed order tracking is performed using this tacho signal. Finally, to reduce the effect of second-order cyclostationarity, CLES tool is used to analyze the incipient fault features. Simulations are carried out and the performances of WE and CLES are compared with traditional method. Furthermore, vibration signals of real experimental data are used to verify the robustness of the proposed method. The experimental results show that the proposed method can effectively maximize the incipient fault signatures of rotating machines. © 2016 IETE

Kim S.-K.S.-K.,Dongguk University | Jo M.-W.,University of Ulsan | Kim S.-H.,Dankook University
PeerJ | Year: 2017

Background and Objective. The Korean version of the EQ-5D-Y was launched in 2015 by the EuroQol group. Currently, there is no HRQOL data obtained by using the EQ- 5D-Y in Korea. This study aimed to measure health-related quality of life of Korean elementary school students using the EQ-5D-Y. Methods. Elementary school students were recruited from 11 primary schools in Gyungbuk, South Korea. The EQ-5D-Y was self-administered in the sample population. Demographic characteristics were collected from the subjects' parents or guardians. The percentage of respondents reporting problems and VAS scores were calculated. Feasibility of the EQ-5D-Y was assessed by analysing the proportion of missing responses. The percentage of reported problems on the dimensions and VAS score between groups were compared by demographic factors. Results. A total of 2,494 questionnaires were collected. There were 24 (0.96%) missing responses on the EQ-5D-Y and 187 (7.5%) missing VAS score responses. The proportion of reported problems ranged from 2.3% on the mobility dimension to 9.8% on the aving pain or discomfort'' dimension. There was no significant difference in the proportion of problems by age group in male participants. However, in females, the older group reported significantly more problems on the having pain or discomfort'' and feeling worried, sad, or unhappy'' dimensions compared to the younger group. Students living with parents with the lowest educational level reported significantly more problems on the looking after myself'' and doing usual activities'' dimensions than did those living with parents with higher levels of education. Discussion. This study showed the distribution of health-related quality of life and explored the feasibility of the EQ-5D-Y for measuring health-related quality of life in Korean elementary school students. Further studies are required to examine other psychometric properties of the Korean EQ-5D-Y. © 2017 Kim et al.

Kim M.,University of Ulsan | Jeong C.W.,Seoul National University | Oh S.-J.,Seoul National University
PLoS ONE | Year: 2017

Purpose To investigate the diagnostic value of urodynamic bladder outlet obstruction (BOO) in the selection of patients for transurethral surgery of the prostate. Materials and methods We systematically searched online PubMed, Embase, and Cochrane Library databases from January 1989 to June 2014. Results A total of 19 articles met the eligibility criteria for this systematic review. The eligible studies included a total of 2321 patients with a median number of 92 patients per study (range: 12-437). Of the 19 studies, 15 conducted conventional transurethral prostatectomy (TURP), and 7 used other or multiple modalities. In urodynamic bladder outlet obstruction (BOO) positive patients, the pooled mean difference (MD) was significant for better improvement of the International Prostate Symptom Score (IPSS) (pooled MD, 3.48; 95% confidence interval [CI], 1.72-5.24; p < 0.01; studies, 16; participants, 1726), quality of life score (QoL) (pooled MD, 0.56; 95% CI, 0.14-1.02; p = 0.010; studies, 9; participants, 1052), maximal flow rate (Qmax ) (pooled MD, 3.86; 95% CI, 2.17-5.54; p < 0.01; studies, 17; participants, 1852), and postvoid residual volume (PVR) (pooled MD, 32.46; 95% CI, 23.34-41.58; p < 0.01; studies, 10; participants, 1219) compared with that in non-BOO patients. Some comparisons showed between-study heterogeneity despite the strict selection criteria of the included studies. However, there was no clear evidence of publication bias in this meta-analysis. Conclusions Our meta-analysis results showed a significant association between urodynamic BOO and better improvements in all treatment outcome parameters. Preoperative UDS mayadd insight into postoperative outcomes after surgical treatment of benign prostatic hyperplasia. © 2017 Kim et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Oh M.,University of Ulsan | Kim J.S.,University of Ulsan | Oh J.S.,University of Ulsan | Lee C.S.,University of Ulsan | Chung S.J.,University of Ulsan
PLoS ONE | Year: 2017

We evaluated cerebellar subregional metabolic alterations in patients with cerebellar ataxia, a representative disease involving the spinocerebellum. We retrospectively analyzed 18Ffluorodeoxyglucose positron emission tomography (18F-FDG PET) images in 44 patients with multiple system atrophy of the cerebellar type (MSA-C), 9 patients with spinocerebellar ataxia (SCA) type 2, and 14 patients with SCA type 6 and compared with 15 patients with crossed cerebellar diaschisis (CCD) and 89 normal controls. Cerebellar subregional metabolism was assessed using 13 cerebellar subregions (bilateral anterior lobes [ANT], superior/ mid/inferior posterior lobes [SUPP/MIDP/INFP], dentate nucleus [DN], anterior vermis [ANTV], and superior/inferior posterior vermis [SUPV/INFV]) to determine FDG uptake ratios. MSA-C and SCA type 2 showed severely decreased metabolic ratios in all cerebellar subregions compared to normal controls (ANT, 0.58 ± 0.08 and 0.50 ± 0.06 vs. 0.82 ± 0.07, respectively, p < 0.001). SCA type 6 showed lower metabolic ratios in almost all cerebellar subregions (ANT, 0.57 ± 0.06, p < 0.001) except INFV. Anterior-posterior lobe ratio measurements revealed that SCA type 2 (Right, 0.81 ± 0.05 vs. 0.88 ± 0.04, p < 0.001; Left, 0.83 ± 0.05 vs. 0.88 ± 0.04, p = 0.003) and SCA type 6 (Right, 0.72 ± 0.05 vs. 0.88 ± 0.04, p < 0.001; Left, 0.72 ± 0.05 vs. 0.88 ± 0.04, p < 0.001) showed preferential hypometabolism in the anterior lobe compared to normal controls, which was not observed in CCD and MSA-C. Asymmetric indices were higher in CCD and MSA-C than in normal controls (p < 0.001), whereas such differences were not found in SCA types 2 and 6. In summary, quantitative analysis of cerebellar subregional metabolism ratios revealed preferential involvement of the anterior lobe, corresponding to the spinocerebellum, in patients with cerebellar ataxia, whereas patients with CCD and MSA-C exhibited more asymmetric hypometabolism in the posterior lobe. © 2017 Oh et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Song J.S.,University of Ulsan
Applied Immunohistochemistry and Molecular Morphology | Year: 2017

Dermatofibrosarcoma protuberans (DFSP) is a low-grade fibroblastic sarcoma with a superficial location that has been suggested to potentially be a type of mesenchymal stem cell tumor. We studied the expression of various immunomarkers, including putative stem cell markers, in a series of 57 DFSPs including variants, and 12 dermatofibromas (DFs). CD105, a mesenchymal stem cell marker, was weakly expressed in 24 DFSPs, whereas other stem cell markers, including CD133, ALK-1, and Oct3/4, were completely negative in all samples. The expression rates of CD105 and CD34 were significantly higher in DFSP (42% and 93%) than in DF (0% and 17%), and CD10 and D2-40 were significantly lower in DFSP (40% and 3.5%) than in DF (100% and 33%), respectively. CD99, CD117, PDGFB, and PDGFRβ expression was comparable between the groups. CD105 mesenchymal cells were not observed in non-neoplastic dermis. In summary, we did not obtain sufficient immunohistochemical evidence to support the DFSP as a cutaneous mesenchymal stem cell tumor. CD34 alone was the most consistent marker of DFSP, irrespective of its variants. Because CD34 non-neoplastic mesenchymal cells were distributed in a location similar to that of DFSP, we suggest that DFSP might have originated from CD34 mesenchymal cells in the dermis. Copyright 2017 Wolters Kluwer Health, Inc. All rights reserved.

Hoang N.-B.,University of Ulsan | Kang H.-J.,University of Ulsan
Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science | Year: 2017

In this paper, we present a novel method for fault identification in the case of an incipient wheel fault in mobile robots. First, a three-layer neural networks is established to estimate the deviation of the robot dynamics due to the process fault. The estimate of the faulty dynamic model is based on a combination of the nominal dynamic model and the neural network output. Then, by replacing the faulty dynamic model with its estimate value, the primary estimates of the wheel radius appear as the solutions of two quadratic equations. Next, a simple and efficient way to perform these primary estimate selections is proposed in order to eliminate undesired primary estimates. A recursive nonlinear least squares is applied in order to obtain a smooth estimate of the wheel radius. Two computer simulation examples using Matlab/Simulink show that the proposed method is very effective for incipient fault identification in the setting of both left and right wheel faults. © Institution of Mechanical Engineers.

Dinh T.X.,University of Ulsan | Ahn K.K.,University of Ulsan
International Journal of Precision Engineering and Manufacturing | Year: 2017

The design of a flight control system for an under-actuated quadrotor aircraft in presence of parametric uncertainties and external disturbance is quite challenging. In this study, we propose an adaptive trajectory tracking control base on sliding mode approach, an adaptive command filtered backstepping technique to stabilize the attitude of the quadrotor and using online estimators to estimate unknown aerodynamic parameters and external disturbances. First of all, the mathematical model of a quadrotor unmanned aerial vehicle (UAV) is presented. The adaptive tracking trajectory position and attitude control scheme are then formulated and the perturbations in quadrotor system are compensated by employing special Lyapunov functions. Simulation results are given to demonstrate the validity and effectiveness of the proposed algorithm on a quadrotor model under different conditions. © 2017, Korean Society for Precision Engineering and Springer-Verlag Berlin Heidelberg.

Lim H.K.,Hyundai Mipo Dockyard Co. | Lee J.-S.,University of Ulsan
International Journal of Naval Architecture and Ocean Engineering | Year: 2017

This paper is concerned with investigating the plastic material properties of steel plate formed by line heating method, and is aimed at implementing more rational design considering the accidental limit states such as collision or grounding. For the present study, line heating test for marine grade steel plate has been carried out with varying plate thickness and heating speed, and then microscopic examination and tensile test have been carried out. From the microscopic, it is found that the grain refined zones like ferrite and pearlite are formed all around the heat affected zone. From the tensile test results, it is seen that yield strength, tensile strength, fracture strain, hardening exponent and strength coefficient vary with plate thickness and heat input quantity. The formulae relating the material properties and heat input parameter should be, therefore, derived for the design purpose considering the accidental impact loading. This paper ends with describing the extension of the present study. © 2016 Society of Naval Architects of Korea.

Kim S.-Y.,University of Ulsan | Park S.-P.,Kyungpook National University
Journal of Oral and Facial Pain and Headache | Year: 2016

Aims: To measure the prevalence of cutaneous allodynia in Korean patients with migraine and to characterize the differential risks of migraine-associated factors and psychiatric disorders in its development. Methods: The study included consecutive patients with migraine who visited headache clinics at two tertiary care hospitals. Questionnaires including the 12-item Allodynia Symptom Checklist (ASC-12) and the Migraine Disability Assessment (MIDAS) were administered to the patients. The Mini International Neuropsychiatric Interview-Plus, Version 5.0.0 (MINI), was performed to diagnose current major depressive disorder (MDD) and current generalized anxiety disorder (GAD). To determine the predictive factors of cutaneous allodynia, a two-step logistic regression model was used. Results: A total of 332 patients were eligible for the study. Chronic migraine (CM) was present in 140 patients (42.2%). Current MDD and current GAD were identified in 73 (21.9%) and 59 patients (17.7%), respectively. Cutaneous allodynia was present in 48 patients (14.5%). Univariate analyses indicated that cutaneous allodynia was associated with female gender, CM, medication overuse headache, headache intensity, photophobia, phonophobia, MIDAS grade, current MDD, and current GAD. Multivariate analyses revealed that current MDD was the strongest risk factor for cutaneous allodynia (adjusted odds ratio [AOR] = 4.552; 95% confidence intervals [CI] = 2.300-9.007; P = .000), followed by CM (AOR = 3.666; 95% CI = 1.787-7.521; P = .000) and photophobia (AOR = 2.707; 95% CI = 1.340-5.469; P = .005). Conclusion: Korean patients with migraine have a low prevalence of cutaneous allodynia. Both depression and migraine-associated features are important factors in the occurrence of cutaneous allodynia. © 2016 by Quintessence Publishing Co Inc.

Park S.H.,University of Ulsan | Seo M.,University of Ulsan | Park T.Y.,University of Ulsan | Nam-Goong S.,University of Ulsan
Hellenic Journal of Nuclear Medicine | Year: 2016

We report a very rare case of incidental intra pericardial thyroid in a papillary thyroid cancer patient. Post ablation scan revealed iodine-131 (131l) uptake in the mid-chest. Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) was performed and showed a 18F-FDG avid lesion between the right atrium and the ascending aorta, which was shown to be an ectopic thyroid and not metastasis. The lesion disappeared on a 6 month follow-up whole body scan while serum thyroglobulin was negative. Although intrapericardial ectopic thyroid is reported to show high iodine uptake, low 18F-FDG avidityofthe lesion could be helpful in theexclusionof metastases.

Hassan K.,University of Ulsan | Chung G.-S.,University of Ulsan
Sensors and Actuators, B: Chemical | Year: 2017

This paper presents theoretical and experimental investigations of quantum-sized (3/3 nm) Pt/Pd bimetallic core-shell nanoparticle (NP)-decorated ZnO nanorod (NR) clusters (Pt/Pd-ZnO NRs) on silicon (Si) substrate for accelerated hydrogen (H2) gas detection. Quantum-size core–shell NP synthesis, metal loading, and Pt/Pd bimetal composition were all carefully controlled by varying the deposition conditions used in the pulsed laser deposition (PLD) system. Theory suggests that the structural arrangement of bimetallic Pt shell around a Pd core can be advantageous in H2 sensing compared to the converse arrangement. Experimental analysis showed that the as-fabricated sensor exhibited a high response magnitude of 58% (10,000 ppm), a fast response time of 5 s, and a broad detection range from 0.2 to 40,000 ppm at the operating temperature of 100 °C. The fabricated sensor also exhibited a good selectivity and a negligible humidity effect over the entire detection range. The superior sensing features of the sensor can be attributed to the enhancement of hydrogen-induced changes in the work function of the Pt/Pd-ZnO NR network. More importantly, the atomic arrangements and chemical potentials of the core–shell interfacial region play vital role in accelerating the H2 sensing properties. © 2016 Elsevier B.V.

Thanh Truc N.T.,University of Ulsan | Lee C.-H.,University of Ulsan | Lee B.-K.,University of Ulsan | Mallampati S.R.,University of Ulsan
Separation and Purification Technology | Year: 2017

Acrylonitrile-butadiene-styrene (ABS) is one of hazardous halogenic plastics which containing brominated flame-retardants (BFRs) is considered as toxic wastes due to releasing hydrogen bromide and brominated dioxins through incineration or disposal activities. In present, recycling is aimed as a sustainable plastic waste management of ABS containing BFRs in ways that minimize the potential impact on human health and environment. This study was conducted to facilitate the separation of ABS plastics from heavy plastic mixture by froth flotation after surface rearrangement of ABS with mild heat treatment for its recycling. Hydrophilic moieties would be more likely to develop on the mild heat-treated ABS surfaces than on other plastics perhaps due to the difference of molecular mobility. This provides an excellent base for selective separation of ABS by froth flotation technique. As a result of froth flotation after mild heat treatment, about 97% of ABS with 100% purity was selectively separated from heavy plastics. The detailed mechanism for the selective separation of the ABS in the treatment (froth flotation after mild heat treatment) was discussed. Finally, this study facilities selective separation application effective and inexpensive method for of ABS from waste plastics. © 2016 Elsevier B.V.

Kim A.,Pusan National University | Heo S.-H.,University of Ulsan | Kim Y.-A.,University of Ulsan | Gong G.,University of Ulsan | Jin Lee H.,University of Ulsan
American journal of clinical pathology | Year: 2016

OBJECTIVES: We tried to describe cellular immune response (tertiary lymphoid structures (TLSs), lymphoid aggregates, tumor infiltrating lymphocytes (TILs)) in neoplastic microenvironment of ductal carcinoma in situ (DCIS) with or without associated microinvasion.METHODS: The histopathologic parameters of 177 DCIS and 27 DCIS with microinvasion were evaluated. We determined number of ducts involved by DCIS, and calculated percentage of these ducts surrounded by TLSs. TILs were quantitated in 27 microinvasive cases.RESULTS: Tumors having higher percentage of DCIS ducts associated with TLSs had higher incidence of microinvasion (P < .001). Percentage of DCIS ducts involved by TLSs was also higher in hormone receptor (HR)-/human epidermal growth factor receptor 2 (HER2)+ and TNBC subtypes of DCIS than in HR+/HER2- and HR+/HER2+ subtypes (38.04 ± 25.8%, 32.6 ± 32.4%, 2.5 ± 7.3% and 17.4 ± 23.3%, respectively, P < .001). In DCIS without microinvasion, HR+/HER2- subtype predominated (P < .001). In microinvasive cases, HR-/HER2+ subtype was most common. TNBC was more common in microinvasive carcinoma than DCIS (P < .001). Among 27 microinvasive ductal carcinomas, increased TLS amount was associated with increased TILs (P = .013).CONCLUSIONS: TLS abundance around DCIS was associated with HER2+ and TNBC subtypes and microinvasion. Pathologists should be aware of microinvasion when diagnosing DCIS lesions with abundant TLSs. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Uddin A.S.M.I.,University of Ulsan | Chung G.-S.,University of Ulsan
Sensors and Actuators, B: Chemical | Year: 2017

Herein, we present a stacked corrugated-core sandwich-structured triboelectric nanogenerator (CCS-TENG) that can be used as an enhanced self-powered active sensor that has a working capability under a broad range of external impacts in the environment. The working performance of a single-unit TENG can be tuned by varying the core diameter of the corrugated-core structure and locating it in a crosswise and/or lengthwise orientation between two sandwich plates. The assembly of the corrugated-core structure also offers a steady gap between the sandwich plates under a strain-free condition. A CCS-TENG with a crosswise assembly exhibits higher electrical output (142–153 V; 3.2–3.9 μA) than with a lengthwise assembly (107–123 V; 2.7–3.1 μA) at a fixed pressing frequency of 3 Hz and different applied forces ranging from 3.0–10.1 N. A constant output voltage of 142 V and an output current of 8.8–9.3 μA are measured at 3–10 Hz and 3.0–10.1 N when four CCS-TENGs with four different core diameters arranged crosswise are stacked in parallel. As a self-powered active hydrogen (H2) sensor, the device can efficiently detect H2 with a high response magnitude (∼83%) and a broad detection range of 0.001–1.000 vol% at the above external frequency and force range. We expect that this exceptional advancement will pave the way for a next-generation self-powered active sensor for integrated systems that has competency under a broad range of external mechanical impacts in the environment. © 2017 Elsevier B.V.

Moon H.,University of Ulsan | Lee J.Y.,University of Ulsan | Sung K.R.,University of Ulsan | Lee J.E.,University of Ulsan
Korean journal of ophthalmology : KJO | Year: 2016

PURPOSE: To investigate the use of ganglion cell inner plexiform layer (GC-IPL) thickness, as measured by spectral domain optical coherence tomography, to detect central visual field (VF) progression.METHODS: This study included 384 eyes from 384 patients (219 preperimetric and 165 perimetric glaucomatous eyes; average follow-up, 4.3 years). Photographic assessment of retinal nerve fiber layer (RNFL) and serial VF analysis were performed to detect glaucoma progression in the central (within 10°) area. Study inclusion required at least five serial spectral domain optical coherence tomography exams at different visits. The long-term test-retest variability of average GC-IPL thicknesses was calculated in 110 stable preperimetric glaucomatous eyes. The sensitivity and specificity of GC-IPL measurements for the detection of central VF progression were calculated in an event-based analysis using the calculated variability as a cut-off and were compared with those of central RNFL photographic assessment.RESULTS: The intersession test-retest variability, defined as the 95% confidence interval, was 1.76 µm for average GC-IPL thickness. The sensitivity and specificity of the average GC-IPL thickness for detecting central VF progression were 60.7% and 78.9%, respectively. Among six sectors, the inferonasal GC-IPL sector showed the highest sensitivity (53.6%). The sensitivity of the ≥1 sector GC-IPL to detect central VF progression was significantly higher than that of central RNFL photographic progression (p = 0.013). Other GC-IPL parameters showed comparable sensitivity and specificity to detect central VF progression compared with RNFL photographic progression.CONCLUSIONS: Serial GC-IPL measurements show comparable performance in the detection of central glaucomatous VF progression to RNFL photographic assessment.

Hong J.W.,University of Ulsan | Yun S.-C.,University of Ulsan | Sung K.R.,University of Ulsan | Lee J.E.,University of Ulsan
Korean journal of ophthalmology : KJO | Year: 2016

PURPOSE: To compare the clinical and anterior segment anatomical features in primary angle closure sub-groups based on configurations of iris root insertion.METHODS: Primary angle closure patients were imaged using anterior segment optical coherence tomography. Anterior chamber depth, iris curvature, iris thickness (IT) at the scleral spur and 500, 750, and 1,500 µm from the scleral spur (IT0, IT500, IT750, and IT1500), lens vault, iris area, angle opening distance (AOD500), angle recess area (ARA750), and trabecular iris space area (TISA750) were measured. Iris root insertion was categorized into a non-basal insertion group (NBG) and basal insertion group (BG).RESULTS: In total, 43 eyes of 39 participants belonged to the NBG and 89 eyes of 53 participants to the BG. The mean age of participants was greater in the NBG than the BG (62.7 ± 5.7 vs. 59.8 ± 7.3 years, p = 0.043), and the baseline intraocular pressure was higher in the BG than the NBG (16.4 ± 4.4 vs. 14.9 ± 3.3 mmHg, p = 0.037). The BG showed a greater IT0 (0.265 ± 0.04 vs. 0.214 ± 0.03 mm, p < 0.001) and iris area (1.59 ± 0.24 vs. 1.52 ± 0.27 mm(2), p = 0.045), lower ARA750 (0.112 ± 0.08 vs. 0.154 ± 0.08 mm(2), p = 0.017) and AOD500 (0.165 ± 0.07 vs. 0.202 ± 0.08 mm, p = 0.014) compared to the NBG.CONCLUSIONS: The BG had a narrower anterior chamber angle, thicker peripheral iris, and higher pretreatment intraocular pressure.

Yun J.-W.,University of Ulsan | Ryu K.Y.,University of Ulsan | Nguyen T.K.,University of Ulsan | Ullah F.,University of Ulsan | And 2 more authors.
RSC Advances | Year: 2017

In this study, we investigate the tuning of the optical band gap of TiO2 nanorods (TiO2 NRs) by electrochemical methods for improving their photocatalytic activities. A seed layer prepared by RF-magnetron sputtering is employed to increase the adhesion between TiO2 NRs and substrate to prevent the peel-off of TiO2 NRs from substrate during electrochemical reduction process. The morphological study shows the stability of TiO2 NRs structure after reduction process. The electrochemical reduction process increased the amount of Ti3+ (a reduced state of Ti4+) and oxygen vacancy by 2.2% and 3.6%, respectively. The process also tune the optical band of TiO2 NRs from 3.0 eV to 2.84 eV due to the up-shift of valence band to Fermi level. The reduced band gap of NRs improve the photocatalytic activities by 1.48 times due the increase of its absorbance range from UV to visible in solar spectrum. The photocatalytic activities were 24.3 times improved by depositing a ultrathin layer of Pt as electron collector. © 2017 The Royal Society of Chemistry.

Tran Thi V.H.,University of Ulsan | Lee B.-K.,University of Ulsan | Ngo C.-V.,University of Ulsan
Journal of the Taiwan Institute of Chemical Engineers | Year: 2017

A composite of ZnO and cotton fabric (ZnO—CF) with a superhydrophobic surface was successfully synthesized with Teflon-lined stainless steel autoclave at low temperature 100 °C. X-ray diffraction (XRD) results indicated that the fabricated ZnO—CF had a uniform stacked hexagonal slice structure without any impurities. The fabric surface firmly bonded with ZnO through chemical bonding and possessed superhydrophobicity with a surface water contact angle (WCA) greater than 150°. The rough structure of ZnO and the enhancement of nonpolar functional groups on the composite surface gave ZnO—CF its superhydrophobicity. ZnO—CF showed a stable and robust self-cleaning property. When applied to separate a mixture of water (dyed with methylene orange) and organic solvent (hexane), ZnO—CF achieved a separation efficiency of over 99% that decreased only insignificantly even after several cycles. Therefore, this outstanding separation performance demonstrates the strong potential of ZnO—CF for practical applications such as wastewater treatment and water purification. © 2016 Taiwan Institute of Chemical Engineers

Tran Thi V.H.,University of Ulsan | Lee B.-K.,University of Ulsan
Journal of Photochemistry and Photobiology A: Chemistry | Year: 2017

A new self-cleaning cotton fabric coated with zinc oxide (ZnO) was obtained via a facile and effective microwave method. The solution pH was a key factor in determining the morphology of ZnO crystal growth on the cotton fibers: rod structures were apt to be formed at pH 4–5, whereas flake and flower-like structures were preferentially formed at higher solution pHs of 6–7 and 10–11, respectively. It is proved that the photocatalytic and wettability performances of ZnO could be efficiently transferred to cotton fabric, leading to a preeminent UV-blocking and self-cleaning cotton fabric. The identified UV protection factors (UPFs) indicate the excellent UV-blocking properties of the ZnO-coated textile fabric synthesized at pH 6–7, 8–9 and 10–11 with UPFs of 222.52, 162.68 and 202.57, respectively. The ZnO coating layer on the cotton fabric significantly improved the wetting behavior of the fabric, such as water absorption speed, thereby affording a self-cleaning ability for the ZnO-coated cotton fabrics. This ability was checked according to the removal degree of coffee stain under UV irradiation at different humidities (30–90% RH). The coffee stains on the ZnO-coated cotton fabrics were almost removed after 15 h without needing any water or detergent and the highest removal effect was observed at 90% humidity. © 2017 Elsevier B.V.

Im H.-G.,Korea Electrotechnology Research Institute | Park G.U.,Korea Electrotechnology Research Institute | Park H.Y.,Korea Electrotechnology Research Institute | Jin J.,University of Ulsan | Kang D.J.,Korea Electrotechnology Research Institute
Progress in Organic Coatings | Year: 2017

Here, we report on the synthesis of a silica nanoparticle (NP)-reinforced oligosiloxane nanohybrid material (SM-nanocomposite) and demonstrate its properties as a robust transparent hard coating material for various applications. The oligosiloxane (MMO) resin as a matrix was synthesized using methyl and methacryl silanes via a hydrolytic sol-gel condensation. The silica NPs with various sizes (12, 20 and 60 nm) as nanofillers were also synthesized through a hydrolytic sol-gel condensation, and the surface of NPs was organically modified with methyl and methacryl functions, which allowed stable dispersion and chemical cross-linking of the NPs with MMO matrix. In this work, we introduce synthetic steps of the nanocomposite and discuss the optical, morphological, thermal and mechanical properties of the composite. © 2017 Elsevier B.V.

Xu L.,Fudan University | Kwak M.,Pukyong National University | Zhang W.,Fudan University | Lee P.C.-W.,University of Ulsan | Jin J.-O.,Fudan University
Molecular Immunology | Year: 2017

Lipopolysaccharide (LPS) is a well-known stimuli of dendritic cells (DCs). However, in vivo spleen DC maturation by Escherichia coli (E.coli) LPS has not been fully investigated. In this study, we examined the effect of LPS on the activation of spleen DCs and its subsets in a time-dependent manner on mice in vivo. The frequency, number and migration of spleen conventional DCs (cDCs) were increased 6 and 12 h after completion of LPS treatment. Those increased DC numbers in spleen were then gradually decreased with apoptosis of the DCs. The highest levels of co-stimulatory molecule expression in the spleen cDCs and their subsets occurred 18 h after LPS treatment, while the pro-inflammatory cytokines reached their maximum in the intracellular levels of the spleen cDCs and their subsets 3 h after LPS treatment. The antigen presentation of the spleen cDCs and their subsets increased gradually from 3 to 12 h after LPS treatment, but those levels decreased rapidly after 18 h post-LPS treatment. Thus, by highlighting the importance of time in the stimulation of spleen DCs by LPS in mice in vivo, our data provided a model that could be used by immunologists when considering the manipulation of DC functions in vivo for experimental and clinical applications. © 2017

Kazuma E.,RIKEN | Jung J.,University of Ulsan | Ueba H.,University of Toyama | Trenary M.,University of Illinois at Chicago | Kim Y.,RIKEN
Journal of the American Chemical Society | Year: 2017

We demonstrate molecular photodissociation on single-crystalline metal substrates, driven by visible-light irradiation. The visible-light-induced photodissociation on metal substrates has long been thought to never occur, either because visible-light energy is much smaller than the optical energy gap between the frontier electronic states of the molecule or because the molecular excited states have short lifetimes due to the strong hybridization between the adsorbate molecular orbitals (MOs) and metal substrate. The S-S bond in dimethyl disulfide adsorbed on both Cu(111) and Ag(111) surfaces was dissociated through direct electronic excitation from the HOMO-derived MO (the nonbonding lone-pair type orbitals on the S atoms (nS)) to the LUMO-derived MO (the antibonding orbital localized on the S-S bond (σ*SS)) by irradiation with visible light. A combination of scanning tunneling microscopy and density functional theory calculations revealed that visible-light-induced photodissociation becomes possible due to the interfacial electronic structures constructed by the hybridization between molecular orbitals and the metal substrate states. The molecule-metal hybridization decreases the gap between the HOMO- and LUMO-derived MOs into the visible-light energy region and forms LUMO-derived MOs that have less overlap with the metal substrate, which results in longer excited-state lifetimes. © 2017 American Chemical Society.

Krishnaswamy H.,Indian Institute of Technology Madras | Kim M.J.,Metal Forming R&D Group | Hong S.-T.,University of Ulsan | Kim D.,Korea Institute of Materials Science | And 3 more authors.
Materials and Design | Year: 2017

Electroplasticity refers to the application of controlled electric pulses during plastic deformation of materials. The electroplasticity phenomenon in metallic materials has led to the development of electrically assisted forming (EAF) process with improved formability. The lack of a suitable constitutive model to describe this electroplastic behaviour is a serious limitation in modelling and optimizing the EAF process. In the present work, a dislocation – density based constitutive model is developed for electroplastic deformation and is capable of predicting the effect of continuous and pulsed electric current during plastic deformation. Single- pulse electroplastic deformation experiments conducted on Al 5052 reveal similar mechanical behaviour as that predicted by the proposed model. The proposed model is also validated against published results for multiple electric pulses using Al 5052. The predicted results correlate well with the experimental data. Based on the predicted results, it is demonstrated that the long range softening observed in certain experiments results from the frequent application of electric pulses and is not due to any other internal softening mechanism. © 2017 Elsevier Ltd

Kim S.-B.,University of Ulsan | Ahn J.-H.,University of Ulsan | Kim J.,University of Ulsan | Jung K.H.,University of Ulsan
Molecular Therapy - Methods and Clinical Development | Year: 2015

A phase 1 clinical trial was conducted to assess the safety, tolerability, and preliminary efficacy of a heterologous prime-boost strategy involving plasmid DNA (pHM-GM-CSF, expressing truncated human epidermal growth factor receptor 2 (HER2) and granulocyte macrophage colony-stimulation factor (GM-CSF) as a bicistronic message) and an adenoviral vector (Ad-HM, containing the same modified HER2 sequence only), in patients with stage III–IV metastatic breast cancer expressing HER2. Nine eligible subjects were divided into three cohorts based on the dosages (2, 4, and 8 mg/patient/visit) of pHM-GM-CSF used as the primer, which was intramuscularly injected three times at weeks 0, 2, and 4. It was followed by a single injection of Ad-HM (3 × 109 virus particles), used as a booster, at week 6. During the 6-month follow-up period, adverse events (AEs), pharmacokinetics and pharmacodynamics, and HER2-specific cellular and humoral immune responses were evaluated. Seven cases of minor grade 1 toxicities in four of nine subjects and no serious drug-related AEs were reported. HER2-specific cell-mediated or humoral immunity was produced in all (100%) or three subjects (33%), respectively. One subject showed a partial response, and seven subjects had stable diseases. However, there were no differences in clinical tumor response and HER2-specific immune responses among the cohorts. These results showed that intramuscular injections of pHM-GM-CSF and Ad-HM were well tolerated and safe. © 2015 Official journal of the American Society of Gene & Cell Therapy

Bellmunt J.,Dana-Farber Cancer Institute | Bellmunt J.,Hospital Del Mar Medical Research Institute | De Wit R.,Netherlands Cancer Institute | Vaughn D.J.,University of Pennsylvania | And 17 more authors.
New England Journal of Medicine | Year: 2017

Background Patients with advanced urothelial carcinoma that progresses after platinum-based chemotherapy have a poor prognosis and limited treatment options. METHODS In this open-label, international, phase 3 trial, we randomly assigned 542 patients with advanced urothelial cancer that recurred or progressed after platinum-based chemotherapy to receive pembrolizumab (a highly selective, humanized monoclonal IgG4? isotype antibody against programmed death 1 [PD-1]) at a dose of 200 mg every 3 weeks or the investigator's choice of chemotherapy with paclitaxel, docetaxel, or vinflunine. The coprimary end points were overall survival and progression-free survival, which were assessed among all patients and among patients who had a tumor PD-1 ligand (PD-L1) combined positive score (the percentage of PD-L1expressing tumor and infiltrating immune cells relative to the total number of tumor cells) of 10% or more. RESULTS The median overall survival in the total population was 10.3 months (95% confidence interval [CI], 8.0 to 11.8) in the pembrolizumab group, as compared with 7.4 months (95% CI, 6.1 to 8.3) in the chemotherapy group (hazard ratio for death, 0.73; 95% CI, 0.59 to 0.91; P=0.002). The median overall survival among patients who had a tumor PD-L1 combined positive score of 10% or more was 8.0 months (95% CI, 5.0 to 12.3) in the pembrolizumab group, as compared with 5.2 months (95% CI, 4.0 to 7.4) in the chemotherapy group (hazard ratio, 0.57; 95% CI, 0.37 to 0.88; P=0.005). There was no significant between-group difference in the duration of progression-free survival in the total population (hazard ratio for death or disease progression, 0.98; 95% CI, 0.81 to 1.19; P=0.42) or among patients who had a tumor PD-L1 combined positive score of 10% or more (hazard ratio, 0.89; 95% CI, 0.61 to 1.28; P=0.24). Fewer treatment-related adverse events of any grade were reported in the pembrolizumab group than in the chemotherapy group (60.9% vs. 90.2%); there were also fewer events of grade 3, 4, or 5 severity reported in the pembrolizumab group than in the chemotherapy group (15.0% vs. 49.4%). CONCLUSIONS Pembrolizumab was associated with significantly longer overall survival (by approximately 3 months) and with a lower rate of treatment-related adverse events than chemotherapy as second-line therapy for platinum-refractory advanced urothelial carcinoma. © 2017 Massachusetts Medical Society.

Ko H.,University of Ulsan | Jeong Y.,University of Ulsan | Kim M.,University of Ulsan
Mutation Research - Genetic Toxicology and Environmental Mutagenesis | Year: 2017

Increasing interest is being paid to the toxicities of dental materials. The purpose of this study was to determine the cytotoxicities and genotoxicities of endodontic compounds to Chinese hamster ovary (CHO-K1) reproductive cells. Cultured CHO-K1 cells were treated with dental formocresol, two types of calcium hydroxide paste, and two types of mineral trioxide aggregate cement for 24 h. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay was performed on each culture, and the micronucleus frequency was determined by performing a micronucleus assay. Alkaline comet assay and γ-H2AX immunofluorescence assay were used to detect DNA damage. Out of the five materials tested, only dental formocresol significantly increased DNA damage. The mineral trioxide aggregate cements based on calcium silicate were not found to be potentially genotoxic. The data suggest that dental formocresol should not be recommended for use in vital pulp therapy on young teeth. © 2017 Elsevier B.V.

Kang S.G.,University of Ulsan | Kang S.G.,Georgia Institute of Technology | Sholl D.S.,Georgia Institute of Technology
Journal of Alloys and Compounds | Year: 2017

Perovskite-structured oxides are promising materials for proton conduction. We use first-principles calculations to investigate the chemical stability and proton conductivity of doped barium hafnate (BaHfO3) and barium stannate (BaSnO3). Previously, we [RSC Adv. 3, 3333 (2013)] reported first-principles calculations examining the chemical stability and proton conductivity of B-site doped BaZrO3 and found that Ga-doping gives the highest chemical stability and La-doping provides the highest proton conductivity in BaZrO3. We use density functional theory (DFT) calculations to examine two other host materials, BaHfO3 and BaSnO3, using these two dopants, Ga and La. We find that doped BaHfO3 is promising to study further in co-doping case, because Ga-doped BaHfO3 demonstrates the high stability and La-doped BaHfO3 shows the high proton conductivity compared to doped BaSnO3 and doped BaZrO3. © 2016 Elsevier B.V.

Sohaib M.,University of Ulsan | Kim J.-M.,University of Ulsan
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2017

In this paper, we propose a hybrid approach for segmenting the left ventricle out of magnetic resonance sequences and apply results of the segmen- tation for heart quantification. The hybrid approach uses a thresholding-based region growing algorithm coupled with gradient vector flow (GVF). Results of the segmentation steps were used for the quantification process and yielded values of 175.4 ± 51.52 (ml), 66 ± 38.97 (ml), and 61.60 ± 12.79 (%) for end diastolic volume (EDV), end systolic volume (ESV), and ejection fraction (EF), respectively. © Springer International Publishing AG 2017.

Islam M.M.M.,University of Ulsan | Islam M.R.,University of Ulsan | Kim J.-M.,University of Ulsan
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2017

This paper proposes a hybrid feature selection scheme for identifying the most discriminant fault signatures using an improved class separability criteria—the local compactness and global separability (LCGS)—of distribution in feature dimension to diagnose bearing faults. The hybrid model consists of filter based selection and wrapper based selection. In the filter phase, a sequential forward floating selection (SFFS) algorithm is employed to yield a series of suboptimal feature subset candidates using LCGS based feature subset evaluation metric. In the wrapper phase, the most discriminant feature subset is then selected from suboptimal feature subsets based on maximum average classification accuracy estimation of support vector machine (SVM) classifier using them. The effectiveness of the proposed hybrid feature selection method is verified with fault diagnosis application for low speed rolling element bearings under various conditions. Experimental results indicate that the proposed method outperforms the state-of-the-art algorithm when selecting the most discriminate fault feature subset, yielding 1.4% to 17.74% diagnostic perfor- mance improvement in average classification accuracy. © Springer International Publishing AG 2017.

Appana D.K.,University of Ulsan | Islam M.R.,University of Ulsan | Kim J.-M.,University of Ulsan
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2017

The k-nearest neighbor (k-NN) method is a simple and highly effective classifier, but the classification accuracy of k-NN is degraded and becomes highly sensitive to the neighborhood size k in multi-classification problems, where the density of data samples varies across different classes. This is mainly due to the method using only a distance-based measure of similarity between different samples. In this paper, we propose a density-weighted distance similarity metric, which considers the relative densities of samples in addition to the distances between samples to improve the classification accuracy of standard k-NN. The performance of the proposed k-NN approach is not affected by the neighborhood size k. Experimental results show that the proposed approach yields better classification accuracy than traditional k-NN for fault diagnosis of rolling element bearings. © Springer International Publishing AG 2017.

Jeong J.-S.,University of Ulsan | Kim H.-T.,University of Ulsan | Kim B.,City University of New York | Cho S.-B.,University of Ulsan
2016 IEEE Asia Pacific Conference on Circuits and Systems, APCCAS 2016 | Year: 2016

In this paper, we used a fisheye lens to acquire the wider rear view camera images. Fisheye lens provided about 170° wide rear view images but the images were distorted because of the characteristics of the lens. In order to compensate this, distorted images were transformed to flat images using a distortion model (FOV). Then, noises of compensated images were removed using filters and the images were converted to grayscale. Grayscale images were then applied to HOG (histogram of gradient) to detect cars approaching from back and the positions of the cars were indicated as colored rectangles. As a future study, we will test our system with harsher environments (such as in darkness, with brightness changes, in different climates) and adjust it to have better recognition rates regardless of environments. We also have a plan to improve our system to evaluate the risk of collision by predicting the velocity and direction of approaching cars. © 2016 IEEE.

Lee J.A.,University of Ulsan | Yoo J.E.,University of Ulsan | Park H.S.,University of Ulsan
Breast Cancer Research and Treatment | Year: 2017

Purpose: To evaluate the risk of breast cancer in middle-aged women with metabolic syndrome using the National Health Insurance Service-National Sample Cohort (NHIS-NSC). Methods: We analyzed 23,820 women aged 50–64 years who participated in the NHIS-NCS in 2008 and 2009. We excluded subjects with any previous history of cancer or with inadequate information regarding metabolic syndrome. Participated subjects underwent anthropometric measurements and provided fasting blood samples for the assessment of glucose and lipid profiles, and answered a lifestyle questionnaire. Cox regression analysis was performed to evaluate relative risks (RRs) and 95% confidence intervals (CIs) for the association between metabolic syndrome and breast cancer. Results: During the 5-year follow-up, 131 subjects were newly diagnosed with breast cancer (incidence, 10.86 per 10,000 person years). After adjusting for age and body mass index, the RR for incident breast cancer in participants with metabolic syndrome versus those without it was 1.47 (95% CI 1.01–2.13). For those individuals of metabolic syndrome, hyperglycemia was most primarily related with the incidence of breast cancer (RR 1.44, 95% CI 1.02–2.04). Conclusions: Among the study individuals who were middle-aged Korean women, metabolic syndrome is highly related with the risk of breast cancer. Therefore, it needs to be managed or prevented to reduce the incidence of breast cancer. © 2017 Springer Science+Business Media New York

Lee D.H.,University of Ulsan
Pharmacology and Therapeutics | Year: 2017

The discovery of epidermal growth factor receptor (EGFR) activating mutations in non-small cell lung cancer (NSCLC) and the success story of EGFR tyrosine kinases inhibitors (TKIs) have changed the paradigm of cancer therapy from empirical cytotoxic chemotherapy to molecular-targeted cancer therapy. As a result, EGFR TKI therapy, including gefitinib, erlotinib and afatinib, has become the standard therapy for NSCLC patients with EGFR activating mutation as first-line therapy. However, most patients inevitably progress despite initial dramatic and rapid response to EGFR TKIs and therefore during the last decade, a lot of efforts have been made to identify and overcome various resistance mechanisms. Fortunately, T790M secondary mutation, the main resistance mechanism, can be overcome by newly developed third-generation EGFR TKIs, such as osimertinib, while most combination trials trying to overcome resistance mechanisms other than T790M mutation have failed so far. To make it worse, spatial and temporal tumor heterogeneity and clonal selection or evolution are also identified in EGFR mutant NSCLC tumors. Nevertheless, advance of comprehensive and more sensitive molecular diagnostics and monitoring technology, such as next-generation sequencing and dynamic monitoring technology using circulating biomarker and development of new cancer medicine with different mechanisms from EGFR TKIs, especially immune checkpoint inhibitors, might affect or change the treatment paradigm of EGFR mutant NSCLC in the near future. © 2017 Elsevier Inc.

Kim H.-T.,University of Ulsan | Jeong J.-S.,University of Ulsan | Kim B.,City University of New York | Cho S.-B.,University of Ulsan
2016 IEEE Asia Pacific Conference on Circuits and Systems, APCCAS 2016 | Year: 2016

This paper deals with the tilt compensation and resolution compensation as the process for efficient recognizing text information on traffic signs of Korea. OCR(Optical Character Recognition), overall processing process for solving structural limit of Template Matching was suggested, and the compensation on tilt was conducted through Hough line and trigonometry. And, resolution compensation for damaged pixels and enhancing image quality of low definition image was settled through FFT(Fast Fourier Transform). © 2016 IEEE.

Dong L.,Nanjing University of Information Science and Technology | Dong L.,Leiden University | Wang Y.,Fudan University | Scipioni A.,University of Padua | And 2 more authors.
Resources, Conservation and Recycling | Year: 2017

Urban infrastructure, as the interface between the socioeconomic activities and natural resources/build environment, is critical to sustainable resource management at urban scale. To address various emerging challenges and capture opportunities for urban transition from an infrastructure system innovation perspective, this Special Issue ("Urban infrastructures system for sustainable resource management") of the journal <. Resources, Conservation & Recycling> highlighted recent progress on characterizing the sustainability of infrastructure system towards sustainable urban development and resource management, based upon comprehensive reviews, regenerative urban infrastructures development and urban industrial symbiosis, novel and integrated planning and evaluation tools/methods, and the innovative policies. The 21 articles in this SI showed that tangible socioeconomic and environmental benefits were able to be achieved from innovation on urban infrastructures system. The results and recommendations provided critical insights on how to promote innovative urban infrastructure development within different contexts. Via reviewing on the articles in this SI, an integrated framework for future research concerns and implications on promoting sustainable urban infrastructure planning and management is proposed, so as to create the synergies for addressing urban and regional environmental quality and impacts, and methods to track the ever-improvements through the established research framework. © 2017 Elsevier B.V.

Chun T.W.,University of Ulsan | Lee H.H.,University of Ulsan | Kim H.G.,Korea University | Nho E.C.,Pukyong National University
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

This paper presents a photo-voltaic generation system using a single-phase grid-connected quasi Z-source inverter (QZSI). The method to track the maximum power point of the PV array by adjusting the shoot-through time of the QZSI is suggested. The modified switching patterns for controlling effectively the shoot-through time while reducing the switching loss are applied. The ac grid current controller with a resonant controller is designed in order to eliminate the steady-state error at the grid frequency, 60Hz. To confirm the effectiveness of proposed methods, some simulation results are shown. © 2011 IEEE.

Han S.-H.,Kyungpook National University | Jo T.-H.,Samsung | Park J.-H.,Kyungpook National University | Kim H.-G.,Kyungpook National University | And 2 more authors.
8th International Conference on Power Electronics - ECCE Asia: "Green World with Power Electronics", ICPE 2011-ECCE Asia | Year: 2011

This paper proposes a new dead time compensation method for a PWM inverter. Recently, PWM inverters are widely used for industrial applications, such as ac motor drives, distributed grid-connected systems and a static synchronous compensator (STATCOM). The nonlinear characteristics of the switch and the dead time cause a current distortion and a deterioration of the power quality. The dominant harmonics is the 5th and 7th harmonics in the stationary reference frame, and the 6th harmonics in the synchronously rotating frame. In this paper, a resonant controller which compensates the 6th harmonics in the synchronously rotating frame is proposed. This method does not require any off-line experimental measurements, additional hardware and complicated mathematical calculations. Furthermore it is easy to implement and does not cause any stability problem. © 2011 IEEE.

Jung S.,Korea Advanced Institute of Science and Technology | Lee D.,Korea Advanced Institute of Science and Technology | Kim S.W.,University of Ulsan | Kim S.Y.,Korea Advanced Institute of Science and Technology
Journal of Fluorescence | Year: 2017

Translational diffusion properties of single-stranded DNA (ssDNA) and G-quadruplexes were studied to determine the persistence length and cooperativity of G-quadruplex formation using FCS combined with HYDRO in which wormlike chain (WLC)-based Monte Carlo simulation are implemented. The presence of a guanine instead of a thymine shortened the contour length of nucleic acids and increased the vulnerability to ion screening. For cooperativity estimation, the telomeric sequence HT72 was assumed to undergo 27 intermediate states, which can be classified as ssDNA, single-G-quadruplex, double-G-quadruplex, and three consecutive G-quadruplexes. Each state type was modeled using a series of beads and appropriate bond lengths, which were obtained from the WLC model. Using the HYDRO program, we calculated diffusion times for each species, and these were used to calculate simulated HT72 diffusion times for mixtures of species in arbitrary KCl concentrations. By comparison between simulated and experimental diffusion properties, we obtained a positive cooperativity of C = 200 from FCS combined with HYDRO. © 2017 Springer Science+Business Media New York

Kim E.-A.,Konyang University | Na J.-M.,University of Ulsan | Kim J.,University of Ulsan | Choi S.Y.,Hallym University | And 2 more authors.
Journal of Neuroimmune Pharmacology | Year: 2017

Because ischaemic stroke is one of the most common brain disorders, diverse effective therapies are urgently required. Recent studies reported a variety of azetidine-based scaffolds for the development of central nervous system-focused lead-like libraries. However, their mechanisms of action and in vivo functions remain unclear. Here, we investigated the potential mechanism and beneficial effects of 3-(naphthalen-2-yl(propoxy)methyl)azetidine hydrochloride (KHG26792), a novel azetidine derivative, on ischaemia/reperfusion (I/R) brain injury. We adapted a mouse brain ischaemia model induced by 2 h of middle cerebral artery occlusion followed by 24 h of reperfusion. We measured apoptotic cell death, inflammatory mediators, free radical generation, and anti-oxidative enzymes activities. We also measured the mitochondrial ATP level and Na+, K+-ATPase and cytochrome c oxidase activities. Using western blotting, we analysed the protein levels of inducible NOS, hypoxia-upregulated protein 1, PTEN-induced putative kinase, uncoupling protein 2, p-Akt, MMP-3, and full-length receptor for advanced glycation end-products (RAGE). KHG26792 significantly improved neurological deficits and brain oedema and suppressed I/R-induced apoptosis. KHG26792 significantly attenuated I/R-induced inflammation and oxidative stress by upregulating SOD and catalase activity, GSH, p-Akt, mitochondrial ATP, Na+, K+-ATPase, cytochrome c oxidase, and soluble RAGE and downregulating iNOS, HYOUP1, and MMP-3, suggesting a potential anti-inflammatory and antioxidant role of KHG26792. This is the first study to show that KHG26792 can protect mouse brains against I/R injury by inhibiting apoptotic damage, modulating inflammation, scavenging free radicals, ameliorating oxidative stress, and improving the energy metabolism of the brain, although the clinical relevance of our findings remains unknown. © 2017 Springer Science+Business Media New York

Tang Q.,University of Ulsan | Kurnianggoro L.,University of Ulsan | Jo K.-H.,University of Ulsan
SII 2016 - 2016 IEEE/SICE International Symposium on System Integration | Year: 2016

Most of the previous works had used SVM or AdaBoost to select the best features and thresholds for object classification. This paper uses statistical and geometrical features for LiDAR-based vehicle detection. We train our system using labeled point sets, which we obtain by manually labeled on KITTI dataset. We also define 11 features of LIDAR point set as input features. According to the test, the correct detection rate is above 98.3%. Experimental results show that our approach can perform accurately and fast, work well in most of cases under our experimental environments. The more data we use, the more accurate experimental result we can obtain. © 2016 IEEE.

Hong J.Y.,University of Ulsan | Suh C.,University of Ulsan | Kim W.S.,Sungkyunkwan University
F1000Research | Year: 2016

Various strategies have been implemented to improve the outcomes of diffuse large B-cell lymphoma (DLBCL). In recent years, remarkable advances have been achieved, based on the discovery of cell-of-origin in DLBCL and on more effective targeted agents. This commentary will summarize recent updates on the evolution of frontline therapies for DLBCL, focusing on the upcoming promising frontline chemotherapy platforms and on activated B-cell subtype DLBCL and double-hit DLBCL. © 2016 Hong JY et al.

Koh Y.,University of Ulsan
Respiratory Investigation | Year: 2017

The acute respiratory distress syndrome (ARDS) is typically manifested by refractory hypoxemia with high mortality. A correct diagnosis is the first step to achieve better outcomes. An early intervention to manage modifiable risk factors of ARDS development and the avoidance of aggravating factors that increase disease severity and progression should be carefully addressed. A management plan is necessary at an early stage of ARDS to determine the level of intensive care. It should be carefully decided which therapeutic measures should be performed depending on the patient's underlying clinical condition. The clinician's considerate prudence is required in decisions of when to apply intensive measures for an ARDS treatment. Mechanical ventilator support should be carefully used depending on the patient's severity and pathological phase. Decreasing inappropriate alveolar strain through a low tidal volume under optimal positive end-expiratory pressure is key for ventilator support in ARDS. The extracorporeal membrane oxygenation applied in the experienced centers seems to improve the survival of patients with severe ARDS. A constellation of physical and psychological problems can develop or persist for up to 5 years in patients with ARDS. Therefore, an early mobilization with rehabilitation, even during an intensive care unit stay, should be seriously considered whenever feasible. Lastly, prevention of aspiration, stress ulcers, deep vein thrombosis, catheter-related infection, overhydration, and heavy sedation is essential to achieve better outcomes in ARDS. © 2017 The Japanese Respiratory Society.

Han S.,Seoul National University | Hyun S.-J.,Seoul National University | Kim K.-J.,Seoul National University | Jahng T.-A.,Seoul National University | And 2 more authors.
Spine Journal | Year: 2017

Background Context: Little is known about the effect of rod stiffness as a risk factor of proximal junctional kyphosis (PJK) after adult spinal deformity (ASD) surgery. Purpose: The aim of this study was to compare radiographic outcomes after the use of cobalt chrome multiple-rod constructs (CoCr MRCs) and titanium alloy two-rod constructs (Ti TRCs) for ASD surgery with a minimum 1-year follow-up. Study Design: Retrospective case-control study in two institutes. Patient Sample: We included 54 patients who underwent ASD surgery with fusion to the sacrum in two academic institutes between 2002 and 2015. Outcome Measures: Radiographic outcomes were measured on the standing lateral radiographs before surgery, 1 month postoperatively, and at ultimate follow-up. The outcome measures were composed of pre- and postoperative sagittal vertical axis (SVA), pre- and postoperative lumbar lordosis (LL), pre- and postoperative thoracic kyphosis (TK)+LL+pelvic incidence (PI), pre- and postoperative PI minus LL, level of uppermost instrumented vertebra (UIV), evaluation of fusion after surgery, the presence of PJK, and the occurrence of rod fracture. Materials and Methods: We reviewed the medical records of 54 patients who underwent ASD surgery. Of these, 20 patients had CoCr MRC and 34 patients had Ti TRC. Baseline data and radiographic measurements were compared between the two groups. The Mann-Whitney U test, the chi-square test, and the Fisher exact test were used to compare outcomes between the groups. Results: The patients of the groups were similar in terms of age, gender, diagnosis, number of three-column osteotomy, levels fused, bone mineral density, preoperative TK, pre- and postoperative TK+LL+PI, SVA difference, LL change, pre- and postoperative PI minus LL, and location of UIV (upper or lower thoracic level). However, there were significant differences in the occurrence of PJK and rod breakage (PJK: CoCr MRC: 12 [60%] vs. Ti TRC: 9 [26.5%], p=.015; occurrence of rod breakage: CoCr MRC: 0 [0%] vs. Ti TRC: 11 [32.4%], p=.004). The time of PJK was less than 12 months after surgery in the CoCr MRC group. However, 55.5% (5/9) of PJK developed over 12 months after surgery in the Ti TRC group. Conclusions: Increasing the rod stiffness by the use of cobalt chrome rod and can prevent rod breakage but adversely affects the occurrence and the time of PJK. © 2017 Elsevier Inc.

Yoon J.O.,University of Ulsan | Baek H.,Ewha Womans University | Kim J.K.,University of Ulsan
Journal of Hand Surgery | Year: 2017

Purpose: We aimed to compare the clinical and radiographic results of patients with a mallet fracture involving more than one-third of the articular surface, but without a high degree of distal interphalangeal (DIP) joint subluxation, treated with extension block pinning or nonsurgical management. Methods: Forty-nine patients with a mallet fracture involving more than one-third of the articular surface were reviewed. Twenty-six cases were treated using extension block pinning (surgery group) and 23 were treated nonsurgically (nonsurgical group). At the final follow-up, extension lag and flexion of the DIP joint of the affected digit were measured. Distal interphalangeal joint pain was rated using a visual analog scale and the overall clinical outcomes were graded using Crawford's criteria. Complications, including nail deformity and dorsal prominence, were also assessed. The rate of DIP joint subluxation and fracture fragment size were radiographically evaluated. Results: Mean extension lag and flexion of the DIP joint and mean visual analog pain scores were not significantly different in the 2 groups. Outcomes, as assessed using Crawford's criteria, were excellent in 5, good in 12, fair in 6, and poor in 3 in the surgery group, and excellent in 2, good in 11, fair in 8, and poor in 2 in the nonsurgical group. Moreover, the frequency of nail deformity or dorsal prominence was similar in the 2 groups. The rate of DIP subluxation and mean fracture fragment size were similar between the 2 groups. All the fractures had united by 3 months after injury in both groups. Conclusions: The clinical outcomes do not significantly differ between extension block pinning and nonsurgical management for mallet fractures involving more than one-third of the articular surface, but without high degree subluxation of the DIP joint. Type of study/level of evidence: Therapeutic IV. © 2017 American Society for Surgery of the Hand.

Lee K.E.,Kangwon National University | Ryu A.-J.,Kangwon National University | Shin E.-S.,University of Ulsan | Shim E.B.,Kangwon National University
Pflugers Archiv European Journal of Physiology | Year: 2017

This work reviews the key aspects of coronary and neurovascular flow reserves with an emphasis on physiomic modeling characteristics by the use of a variety of numerical approaches. First, we explain the definition of fractional flow reserve (FFR) in coronary artery and introduce its clinical significance. Then, computational researches for obtaining FFR are reviewed, and their clinical outcomes are compared. In the case of cerebrovascular reserve (CVR), in spite of substantial progress in the simulation of cerebral hemodynamics, only a few computational studies exist. Thus, we discuss the limitations of CVR simulation study and suggest the challenging issue to overcome these. Also, the future direction of physiomic researches for the flow reserves in coronary arteries and cerebral arteries is described. Also, we introduce a machine learning algorithm trained by the existing physiomic simulation data of flow reserve and suggest a prospective research direction related to this. © 2017 Springer-Verlag Berlin Heidelberg

Uddin A.S.M.I.,University of Ulsan | Chung G.-S.,University of Ulsan
Proceedings of IEEE Sensors | Year: 2017

In this work, we presented a self-powered active hydrogen (H2) sensor based on triboelectric effect using Pd nanoparticles (NPs) decorated ZnO nanorods (NRs) array and micropatterned (wrinkle) poly-dimethylsiloxane (PDMS). The triboelectric output of the as-fabricated device was used as the nanogenerator output as well as the sensor output. Under 5.3 N contact force and at a fixed pressing frequency of 3 Hz, generated open-circuit voltage and short-circuit current of the device can reach to 16.2 V and 0.5 μA, respectively. The output power density was measured to be nearly 15.8μW/cm2 when connecting to a load resistor of 1 ΜΩ. Upon exposure to 3 vol% H2 gas under the optimum conditions, the device output voltage dropped from 16.2 V (in dry air) to 1.04 V, showing a maximum sensor response of 1457.7%. The device also showed minimum detection of H2 down to 20 ppm. The proposed work suggests that the device can be used as a possible mean for the development of next-generation portable self-powered active sensors. © 2016 IEEE.

Yang D.-H.,University of Ulsan
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi | Year: 2015

Ulcerative colitis is an idiopathic chronic inflammatory bowel disease and its incidence in Korea has rapidly increased over the past two decades. Since ulcerative colitis is associated with increased risk for colorectal cancer, annual or biannual colonoscopy with four quadrant random biopsies at every 10 cm segments has been recommended for surveillance of colitic cancer in patients with long standing left-sided or extensive colitis. Recent epidemiologic data and meta-analysis suggest that the increment of colorectal cancer risk in ulcerative colitis was not larger than that of previous studies. Moreover, in addition to the extent and duration of colitis, other risk factors such as family history of colorectal cancer, primary sclerosing cholangitis, stricture, pseudopolyps, and histologic severity of inflammation have been recognized. As a result, updated guidelines provide surveillance strategies adjusted to the individual patient's risk for colitic cancer. Regarding surveillance method, target biopsy under panchromoendoscopy is preferentially recommended rather than random biopsy.

Kim J.H.,University of Ulsan
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi | Year: 2015

What is medical professionalism and does it matter to the patients? Medical professionals take responsibility for their judgements and the consequences that ensue. Traditionally medical professionalism is defined as a set of values, behaviors, and relationships which support the trust the public has in doctors. The public is well aware that absence of professionalism is harmful to their interests. However, the exercise of medical professionalism is endangered by the political and cultural environment. The values of professionalism have been changed throughout the medical history and the meaning of it was also changed according to social theories. Traditional medical professionalism was based on the virtue of autonomy, self-regulation and competency etc. However, in the new millenium era, the meaning of professionalism has changed under the concept of responsibility which includes the classical virtues. The meaning of professionalism nowadays is only based on the structure and conflicting theories which cannot solve all the issues surrounding professionalism in medical practice. The conditions of medical practice are critical determinants for the future of professionalism. The interaction between doctor and patient is central to the medical care, and medical professionalism has roots in almost every aspect of medical care. I argue that doctors have responsibility to act according to the values which have been determined by the medical profession, history and surrounding society. The new millennium medical professionalism which based on the responsibility could initiate a public dialogue about the role of the doctor in creating a fairer society.

Gurunathan T.,University of Ulsan | Chung J.S.,University of Ulsan
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2017

A series of cottonseed oil based waterborne polyurethane–silica (CSOWPU–Si) hybrid materials were prepared via the chemically interaction between NCO groups of polyurethane prepolymer and the surface of 3-aminopropyl trimethoxysilane (APTMS). The biobased triglyceride oils were first epoxidized cottonseed oil followed by oxirane ring-opened with varying polyhydroxy ([sbnd]OH) fatty acid numbers. The attached modified APTMS thus performed the dual roles not only chain extender filler but including reinforcing agent in the resulting hybrid coatings. Fourier transform infrared spectra expose the crosslinking interaction between polyurethane and the appearance of silica nanoparticles in the polymer matrix. The 29Si solid-state NMR spectra sign the formation and the behavior of siloxane linkage in the CSOWPU–Si nanocomposites films. Dynamic mechanical analysis (DMA) studies show that the appearance of silica nanoparticles provides rigidity to CSOWPU–Si film, thereby enhancing the storage modulus. The effect of crosslinking density and thermophysical and mechanical properties of the polyurethane and the resulting hybrid materials films was evaluated by the differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and measurement of the mechanical properties. This work renders a new effective and promising route of utilizing biorenewable for the development of CSOWPU–Si hybrid materials with high performance coating applications. © 2017 Elsevier B.V.

Lee D.-H.,University of Ulsan | Joo Y.-S.,University of Ulsan | Hwang C.J.,University of Ulsan | Lee C.S.,University of Ulsan | Cho J.H.,University of Ulsan
Journal of neurosurgery. Spine | Year: 2017

OBJECTIVE Although posterior decompressive surgery is widely used to treat patients with cervical myelopathy and multilevel ossification of the posterior longitudinal ligament (OPLL), a poor outcome is anticipated if the sagittal alignment is kyphotic (or K-line negative). Accordingly, it is mandatory to perform anterior decompression and fusion in patients with cervical kyphosis. However, it can be difficult to perform anterior surgery because of the high risk of complications. This present report proposes a novel "greenstick fracture technique" to change the K-line from negative to positive in patients with cervical myelopathy, OPLL, and kyphotic deformity. METHODS Four patients with cervical myelopathy, continuous-type OPLL, and kyphotic sagittal alignment (who were K-line negative) were indicated for surgery. Posterior laminectomy and lateral mass screw insertions using a posterior approach were performed, followed by anterior surgery. Multilevel discectomy and thinning of the OPLL mass by bur drilling was performed, then an intentional greenstick fracture at each disc level was made to convert the cervical K-line from negative to positive. Finally, posterior instrumentation using a rod was carried out to maintain cervical lordosis. RESULTS MRI showed complete decompression of the cord by posterior migration in all cases, which had been caused by cervical lordosis. Restoration of neurological defects was confirmed at the 1-year follow-up assessment. No specific complications were identified that were associated with this technique. CONCLUSIONS A greenstick fracture technique may be effective and safe when applied to patients with cervical myelopathy, continuous-type OPLL, and kyphotic deformity (K-line negative). However, further studies with more cases will be required to reveal its generalizability and safety.

Hahn I.K.,University of Ulsan | Kim J.Y.,University of Ulsan | Kim M.J.,University of Ulsan | Tchah H.,University of Ulsan | Moon C.H.,University of Ulsan
Korean journal of ophthalmology : KJO | Year: 2017

PURPOSE: To assess the validity of central corneal thickness (CCT) and corrected intraocular pressure (IOP) values obtained by tono-pachymetry in non-surgical and post-photorefractive keratectomy (PRK) eyes.METHODS: For the study, 108 young healthy participants and 108 patients who had PRK were enrolled. Measurements were randomly performed by tono-pachymetry, ultrasonic (US) pachymetry, and Goldmann applanation tonometry (GAT). CCT measurement by tono-pachymetry was compared to that of US pachymetry. The corrected IOP value obtained by tono-pachymetry was compared to that obtained by US pachymetry and GAT. The corrected IOP from US pachymetry and GAT was calculated using the identical compensation formula built into the tono-pachymetry. Bland-Altman plot and paired t-test were conducted to evaluate the between-method agreements.RESULTS: The mean CCT measurement using tono-pachymetry was significantly greater by 7.3 µm in non-surgical eyes (p < 0.001) and 17.8 µm in post-PRK eyes (p < 0.001) compared with US pachymetry. Differences were significant in both Bland-Altman plotand paired t-test. The mean difference of corrected IOP values obtained by tono-pachymetry and calculated from measurements by US pachymetry and GAT was 0.33 ± 0.87 mmHg in non-surgical eyes and 0.57 ± 1.08 mmHg in post-PRK eyes. The differences in the Bland-Altman plot were not significant.CONCLUSIONS: The CCT measurement determined using tono-pachymetrywas significantly thicker than that of US pachymetry. The difference in CCT was greater in post-PRK eyes than in non-surgical eyes. However, the corrected IOP value obtained by tono-pachymetry showed reasonable agreement with that calculated from US pachymetry and GAT measurements.

Chun B.,University of Ulsan | Kim J.,University of Ulsan
Korean Chemical Engineering Research | Year: 2017

The performance of polymer electrolyte membrane fuel cell (PEMFC) could be deteriorated when fuel contains contaminants such as carbon monoxide (CO) or hydrogen sulfide (H2S). Generally, H2S is introduced in hydrogen by steam reforming of hydrocarbon which has mercaptan as odorant. H2S poisoning effect on PEMFC performance was examined on this study. Pure hydrogen injection, voltage cycling and water circulation methods were compared as performance recovery methods. The PEMFC performance was analyzed using electrochemical methods such as polarization curve, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). Pure hydrogen injection and voltage cycling methods showed low recovery ratio, however, water circulation method showed high recovery ratio over 95%. Because anode was directly poisoned by H2S, anode water circulation showed higher recovery ratio compared to the other methods. Water circulation method was developed to recover PEMFC performance from H2S poisoning. This method could contribute to PEMFC durability and commercialization. © 2017, Korean Institute of Chemical Engineers. All rights reserved.

PubMed | Shizuoka Cancer Center, Aichi Cancer Center Hospital, National Hospital Organization Shikoku Cancer Center, Sano Hospital and 18 more.
Type: Journal Article | Journal: Chinese journal of cancer | Year: 2016

Capecitabine and irinotecan combination therapy (XELIRI) has been examined at various dose levels to treat metastatic colorectal cancer (mCRC). Recently, in the Association of Medical Oncology of the German Cancer Society (AIO) 0604 trial, tri-weekly XELIRI plus bevacizumab, with reduced doses of irinotecan (200mg/mThe Asian XELIRI ProjecT (AXEPT) is an East Asian collaborative, open-labelled, randomized, phase III clinical trial which was designed to demonstrate the non-inferiority of XELIRI with or without bevacizumab versus standard FOLFIRI (5-fluorouracil, leucovorin, and irinotecan combination) with or without bevacizumab as second-line chemotherapy for patients with mCRC. Patients with 20years of age or older, histologically confirmed mCRC, Eastern Cooperative Oncology Group performance status 0-2, adequate organ function, and disease progression or intolerance of the first-line regimen will be eligible. Patients will be randomized (1:1) to receive standard FOLFIRI with or without bevacizumab (5mg/kg on day 1), repeated every 2weeks (FOLIRI arm) or XELIRI with or without bevacizumab (7.5mg/kg on day 1), repeated every 3weeks (XELIRI arm). A total of 464 events were estimated as necessary to show non-inferiority with a power of 80% at a one-sided of 0.025, requiring a target sample size of 600 patients. The 95% confidence interval (CI) upper limit of the hazard ratio was pre-specified as less than 1.3.The Asian XELIRI ProjecT is a multinational phase III trial being conducted to provide evidence for XELIRI with or without bevacizumab as a second-line treatment option of mCRC. Trial registration ClinicalTrials.gov NCT01996306. UMIN000012263.

PubMed | University of Queensland, University of Houston, IRCCS Instituto Tumori Giovanni Paolo II, Dana-Farber Cancer Institute and 25 more.
Type: Journal Article | Journal: Nature | Year: 2016

We analysed whole-genome sequences of 560 breast cancers to advance understanding of the driver mutations conferring clonal advantage and the mutational processes generating somatic mutations. We found that 93 protein-coding cancer genes carried probable driver mutations. Some non-coding regions exhibited high mutation frequencies, but most have distinctive structural features probably causing elevated mutation rates and do not contain driver mutations. Mutational signature analysis was extended to genome rearrangements and revealed twelve base substitution and six rearrangement signatures. Three rearrangement signatures, characterized by tandem duplications or deletions, appear associated with defective homologous-recombination-based DNA repair: one with deficient BRCA1 function, another with deficient BRCA1 or BRCA2 function, the cause of the third is unknown. This analysis of all classes of somatic mutation across exons, introns and intergenic regions highlights the repertoire of cancer genes and mutational processes operating, and progresses towards a comprehensive account of the somatic genetic basis of breast cancer.

PubMed | University of Ulsan
Type: Journal Article | Journal: Journal of cardiac surgery | Year: 2016

Surgical techniques currently used for the repair of Ebsteins anomaly comprise reconstruction of the tricuspid valve mechanism at the level of the true annulus with or without plication of the atrialized right ventricle. However, performing this procedure for patients with a dysmorphic anterior leaflet (i.e., insufficient leaflet tissue and decreased mobility due to tethering) may necessitate technical modifications.A retrospective review was performed of 31 patients (seven males and 24 females, median age at operation 31 years) with Ebsteins anomaly, who underwent tricuspid valve repair between March 2002 and December 2014. The original Hetzer technique (annulus to annulus approximation) was employed for six patients with a well-formed anterior leaflet. In 25 patients, the tricuspid valve mechanism was restored at the displaced septal leaflet by approximating the anterior leaflet attachment in the true annulus to the displaced septal leaflet attachment in the mid-septum. A bidirectional superior cavopulmonary anastomosis was added in 27 of 31 (87%) patients.No early or late death occurred during the median follow-up of 66 months (1-138 months). Immediate postoperative tricuspid regurgitation was trivial to mild in 22 patients, and the median preoperative, immediate postoperative, and last follow-up tricuspid regurgitation jet areas in 21 adult patients were 23.3cm2, 10.4cm2, and 7.0cm2, respectively. Two patients underwent reoperation at 81 and 119 months postoperatively. Five-year freedom from severe tricuspid regurgitation or reoperation was 93.2%.Restoration of the tricuspid valve mechanism at the level of displaced septal leaflet leads to excellent long-term outcomes. The addition of the bidirectional superior cavopulmonary anastomosis has contributed to the success of this technique.

PubMed | St. Mary's University, Sacred Heart College, Korea Cancer Center Hospital, Seoul National University and 12 more.
Type: | Journal: Cancer medicine | Year: 2016

We analyzed the treatment responses, toxicities, and survival outcomes of patients with relapsed or refractory multiple myeloma who received daily thalidomide, cyclophosphamide, and dexamethasone (CTD) or daily thalidomide, melphalan, and prednisolone (MTP) at 17 medical centers in Korea. Three-hundred and seventy-six patients were enrolled. The combined chemotherapy of thalidomide, corticosteroid, and an alkylating agent (TAS) was second-line chemotherapy in 142 (37.8%) patients, and third-line chemotherapy in 135 (35.9%) patients. The response rate overall was 69.4%. Patients who were not treated with bortezomib and lenalidomide before TAS showed a higher response rate compared to those who were exposed to these agents. The estimated median progression-free survival and overall survival times were 10.4months and 28.0months, respectively. The adverse events during TAS were generally tolerable, but 39 (10.4%) patients experienced severe infectious complications. There were no differences in terms of efficacy between CTD and MTP, but infectious complications were more common in CTD group. TAS is an effective treatment regimen which induces a high response rate in relapsed or refractory multiple myeloma patients. Due to the high incidence of grade 3 or 4 infection, proper management of infection is necessary during the TAS treatment, especially the CTD.

PubMed | Yonsei University, SNP Genetics Inc., University of Ulsan, Center for Genomic science and 9 more.
Type: | Journal: Human molecular genetics | Year: 2016

Hirschsprung disease (HSCR) is the most common cause of neonatal intestinal obstruction. It is characterized by the absence of ganglia in the nerve plexuses of the lower gastrointestinal tract. So far, three common disease-susceptibility variants at the RET, SEMA3 and NRG1 loci have been detected through genome-wide association studies (GWAS) in Europeans and Asians to understand its genetic etiologies. Here we present a trans-ethnic meta-analysis of 507 HSCR cases and 1191 controls, combining all published GWAS results on HSCR to fine-map these loci and narrow down the putatively causal variants to 99% credible sets. We also demonstrate that the effects of RET and NRG1 are universal across European and Asian ancestries. In contrast, we detected a European-specific association of a low-frequency variant, rs80227144, in SEMA3 [odds ratio (OR) = 5.2, P=4.7 10

PubMed | University of Ulsan, Sungkyunkwan University, Center for Cohort Studies, MRC Integrative Epidemiology Unit and Seoul National University
Type: | Journal: International journal of epidemiology | Year: 2017

We examined whether alcohol flushing could be used as an instrumental variable (IV) and investigated the effect of alcohol consumption on coronary calcification using alcohol flushing status as an IV.We analysed cross-sectional data from 24681 Korean adults (20696 men and 3985 women) who had been administered a questionnaire assessing alcohol consumption and alcohol flushing, as well as a coronary artery calcium (CAC) measurement. The associations of alcohol flushing status with potential confounders and alcohol consumption were examined. We employed two-stage predictor substitution methodology for the IV analysis.The prevalence of alcohol flushing did not differ depending on gender, education, household income, cigarette smoking or physical activity. Balanced levels of confounders were observed between alcohol flushers and non-flushers. Alcohol flushing was closely related to alcohol consumption and levels of liver enzymes. In men, a doubling in alcohol consumption was associated with increased odds of coronary calcification in both the IV analysis [odds ratio (OR) of CAC scores of 1 or over = 1.11; 95% confidence interval (CI) = 1.03-1.20) and the multivariable regression analysis (OR=1.04; 95% CI=1.01-1.07). For cardiovascular risk factors, the IV analysis showed a positive association between alcohol consumption and blood pressure and high-density lipoprotein-cholesterol.Alcohol flushing can be used as an IV in studies evaluating the health impact of alcohol consumption, especially in East Asian countries. Through such an analysis, we found that increased alcohol consumption was associated with an increased risk of subclinical coronary atherosclerosis.

PubMed | Cardiovascular Research Foundation and University of Ulsan
Type: Journal Article | Journal: The American journal of cardiology | Year: 2016

Lesion morphology poorly predicts functional significance of intermediate coronary artery stenosis. The aim of this study was to determine whether a coronary artery-based myocardial segmentation method that quantifies subtended myocardium can improve the diagnostic accuracy of intravascular ultrasound (IVUS)-derived parameters for detecting ischemia-producing lesions. Coronary computed tomography angiography, IVUS, and fractional flow reserve (FFR) data were analyzed in 101 non-left main lesions (20% to 80% angiographic stenosis). Using the coronary artery-based myocardial segmentation method, total left ventricular myocardial volume (Vtotal), myocardial volume subtended by the stenotic coronary segment (Vsub), and Vratio (the ratio of the Vsub to the Vtotal) were assessed. Both Vsub >30.7cm(3) and Vratio >25.4% were determinants of FFR 0.75 (area under the curve= 0.696 and 0.744). Overall, an IVUS-measured minimum lumen area (IVUS-MLA) 2.83mm(2) predicted FFR 0.75 with a sensitivity 88% and specificity 73%. Among lesions with IVUS-MLA 2.83mm(2) and FFR >0.75, 89% showed Vsub <30.7cm(3). In 50 lesions with Vsub >30.7cm(3), an IVUS-MLA 2.85mm(2) predicted FFR 0.75 with sensitivity 85%, specificity 92%, positive predictive value 92%, and negative predictive value 85%. Conversely, in 51 lesions with a Vsub 30.7cm(3), IVUS-MLA 2.67mm(2) showed sensitivity 100%, specificity 69%, positive predictive value 38%, and negative predictive value 100% for predicting FFR 0.75. Body surface area, reference lumen diameter, and vessel area had modest correlations with Vsub. In those lesion subsets, IVUS-MLA 2.8mm(2) accurately predicted an FFR 0.75, whereas the clinical relevance of assessing and treating lesions with a smaller myocardial territory may be limited (ClinicalTrials.gov number NCT1696006).

PubMed | National Cheng Kung University, Yonsei University, University of Ulsan, Harvard University and 17 more.
Type: | Journal: JAMA oncology | Year: 2016

REACH is the first phase 3 trial to provide information on hepatocellular cancer (HCC) in the second-line (postsorafenib) setting categorized by Child-Pugh score, a scoring system used to measure the severity of chronic liver disease. This exploratory analysis demonstrates the relationship between a potential ramucirumab survival benefit, severity of liver disease, and baseline -fetoprotein (FP).To assess treatment effects and tolerability of ramucirumab by Child-Pugh score in patients with HCC enrolled in the REACH trial.Randomized, double-blind, phase 3 trial of ramucirumab and best supportive care vs placebo and best supportive care as second-line treatment in patients with HCC enrolled between November 4, 2010 and April 18, 2013, from 154 global sites. Overall, 643 patients were randomized and included in this analysis; 565 patients considered Child-Pugh class A (Child-Pugh scores 5 and 6) and 78 patients considered class B (Child-Pugh scores 7 and 8).Ramucirumab (8 mg/kg) or placebo intravenously plus best supportive care every 2 weeks.Overall survival (OS), defined as time from randomization to death from any cause.In the randomized population of 643 patients (mean [SD] age, 62.8 [11.1] years) in this analysis, a potential ramucirumab OS benefit was observed for patients with a Child-Pugh score of 5 (hazard ratio [HR], 0.80; 95% CI, 0.63-1.02; P=.06) but no apparent benefit for patients with Child-Pugh scores of 6 or 7 and 8. In patients with baseline FP levels of 400 ng/mL (to convert ng/mL to g/L, multiply by 1.0) or more, a ramucirumab OS benefit was significant for a score of Child-Pugh 5 (HR, 0.61; 95% CI, 0.43-0.87; P=.01) and Child-Pugh 6 (HR, 0.64; 95% CI, 0.42-0.98; P=.04), but was not significant for Child-Pugh 7 and 8. The overall safety profile of ramucirumab, regardless of Child-Pugh score, was considered manageable. Regardless of treatment arm, patients with Child-Pugh scores of 7 and 8 experienced a higher incidence of grade 3 or higher treatment-emergent adverse events, including ascites and asthenia, and special-interest events, including liver injury and/or failure and bleeding, compared with patients with Child-Pugh scores of 5 or 6.In unselected patients, a trend for ramucirumab survival benefit was observed only for patients with a Child-Pugh score of 5. In patients with baseline FP levels of 400 ng/mL or more, a ramucirumab survival benefit was observed for Child-Pugh scores of 5 and 6. Ramucirumab had a manageable toxic effect profile. These results support the ongoing REACH-2 study of ramucirumab in patients with advanced HCC with underlying Child-Pugh A cirrhosis and baseline FP levels of 400 ng/mL or more.clinicaltrials.gov Identifier: NCT01140347.

PubMed | Ajou University, University of Ulsan, Sogang University and Seoul National University
Type: Comparative Study | Journal: Liver international : official journal of the International Association for the Study of the Liver | Year: 2015

Hepatitis B virus (HBV) infection is the most serious risk factor for chronic hepatitis B (CHB), cirrhosis, and hepatocellular carcinoma. Recently, several genome-wide association studies (GWASs) identified important variants associated with the risk of CHB in Asian populations. Specifically, our previous GWAS identified the VARS2-SFTA2 gene region as one of the genetic risk loci for CHB.To further characterize this association and to isolate possible causal variants within it, we performed an additional association study by genotyping more SNPs in the vicinity of the VARS2 and SFTA2 genes. In all, 14 SNPs of VARS2-SFTA2 were analysed among a total of 3902 subjects (1046 cases and 2856 controls).Logistic regression analysis revealed that six SNPs, including the previously reported rs2532932, were significantly associated with the risk of CHB (P = 1.7 10(-10) ~0.002). Further linkage disequilibrium and conditional analysis identified two variants (rs9394021 and rs2517459) as new markers of genetic risk factors for CHB rather than the reported SNP from our previous study (rs2532932). To evaluate the cumulative risk for CHB based on all known genetic factors, genetic risk score (GRS) were calculated. As anticipated, the distribution of the number of risk alleles in cases vs. controls clearly differed according to the GRS. Similarly, the odds ratios (ORs) were increased (OR = 0.32-3.97).Our findings show that common variants in the VARS2-SFTA2 gene region are significantly associated with CHB in a Korean population, which may be useful in further understanding genetic susceptibility to CHB.

PubMed | Samsung, University of Ulsan, Seoul National University, Medical University of Bialystok and 13 more.
Type: Clinical Trial, Phase III | Journal: The Lancet. Oncology | Year: 2016

Trastuzumab resistance is a key therapeutic challenge in metastatic breast cancer. We postulated that broader inhibition of ErbB receptors with afatinib would improve clinical outcomes compared with HER2 inhibition alone in patients who had progressed on previous trastuzumab treatment. LUX-Breast 1 compared afatinib plus vinorelbine with trastuzumab plus vinorelbine for such patients with HER2-positive metastatic breast cancer.We did this open-label trial at 350 hospitals in 41 countries worldwide. We enrolled female patients with HER2-overexpressing metastatic breast cancer who had progressed on or following adjuvant trastuzumab or first-line treatment of metastatic disease with trastuzumab. Participants were randomly assigned (2:1) to receive oral afatinib (40 mg/day) plus intravenous vinorelbine (25 mg/m(2) per week) or intravenous trastuzumab (2 mg/kg per week after 4 mg/kg loading dose) plus vinorelbine. Randomisation was done centrally and stratified by previous trastuzumab treatment (adjuvant vs first-line treatment), hormone receptor status (oestrogen receptor and progesterone receptor positive vs others), and region. The primary endpoint was progression-free survival, assessed in the intention-to-treat population. This trial is closed to enrolment and is registered with ClinicalTrials.gov, NCT01125566.Between Aug 26, 2010, and April 26, 2013, we enrolled 508 patients: 339 assigned to the afatinib group and 169 assigned to the trastuzumab group. Recruitment was stopped on April 26, 2013, after a benefit-risk assessment by the independent data monitoring committee was unfavourable for the afatinib group. Patients on afatinib plus vinorelbine had to switch to trastuzumab plus vinorelbine, afatinib monotherapy, vinorelbine monotherapy, or receive treatment outside of the trial. Median follow-up was 93 months (IQR 37-160). Median progression-free survival was 55 months (95% CI 54-56) in the afatinib group and 56 months (53-73) in the trastuzumab group (hazard ratio 110 95% CI 086-141; p=043). The most common drug-related adverse events of grade 3 or higher were neutropenia (190 [56%] of 337 patients in the afatinib group vs 102 [60%] of 169 patients in the trastuzumab group), leucopenia (64 [19%] vs 34 [20%]), and diarrhoea (60 [18%] vs none).Trastuzumab-based therapy remains the treatment of choice for patients with HER2-positive metastatic breast cancer who had progressed on trastuzumab.Boehringer Ingelheim.

PubMed | Novartis, Chang Gung University, Head, Szent Imre University Teaching Hospital and 16 more.
Type: | Journal: The Lancet. Oncology | Year: 2017

Phosphatidylinositol 3-kinase (PI3K) pathway activation in squamous cell carcinoma of the head and neck contributes to treatment resistance and disease progression. Buparlisib, a pan-PI3K inhibitor, has shown preclinical antitumour activity and objective responses in patients with epithelial malignancies. We assessed whether the addition of buparlisib to paclitaxel improves clinical outcomes compared with paclitaxel and placebo in patients with recurrent or metastatic squamous cell carcinoma of the head and neck.In this multicentre, randomised, double-blind, placebo-controlled phase 2 study (BERIL-1), we recruited patients aged 18 years and older with histologically or cytologically confirmed recurrent and metastatic squamous cell carcinoma of the head and neck after disease progression on or after one previous platinum-based chemotherapy regimen in the metastatic setting. Eligible patients were enrolled from 58 centres across 18 countries and randomly assigned (1:1) to receive second-line oral buparlisib (100 mg once daily) or placebo, plus intravenous paclitaxel (80 mg/mBetween Nov 5, 2013, and May 5, 2015, 158 patients were enrolled and randomly assigned to receive either buparlisib plus paclitaxel (n=79) or placebo plus paclitaxel (n=79). Median progression-free survival was 46 months (95% CI 35-53) in the buparlisib group and 35 months (22-37) in the placebo group (hazard ratio 065 [95% CI 045-095], nominal one-sided p=0011). Grade 3-4 adverse events were reported in 62 (82%) of 76 patients in the buparlisib group and 56 (72%) of 78 patients in the placebo group. The most common grade 3-4 adverse events (occurring in 10% of patients in the buparlisib group vs the placebo group) were hyperglycaemia (17 [22%] of 76 vs two [3%] of 78), anaemia (14 [18%] vs nine [12%]), neutropenia (13 [17%] vs four [5%]), and fatigue (six [8%] vs eight [10%]). Serious adverse events (regardless of relation to study treatment) were reported for 43 (57%) of 76 patients in the buparlisib group and 37 (47%) of 78 in the placebo group. On-treatment deaths occurred in 15 (20%) of 76 patients in the buparlisib group and 17 (22%) of 78 patients in the placebo group; most were caused by disease progression and none were judged to be related to study treatment.On the basis of the improved clinical efficacy with a manageable safety profile, the results of this randomised phase 2 study suggest that buparlisib in combination with paclitaxel could be an effective second-line treatment for patients with platinum-pretreated recurrent or metastatic squamous cell carcinoma of the head and neck. Further phase 3 studies are warranted to confirm this phase 2 finding.Novartis Pharmaceuticals Corporation.

PubMed | Cheng Hsin General Hospital, University of Ulsan, National Taiwan University Hospital, Queen Elizabeth Hospital and 7 more.
Type: Journal Article | Journal: JACC. Cardiovascular interventions | Year: 2016

This study describes the characteristics of a real-world Asian patient population treated with transcatheter aortic valve replacement (TAVR) and evaluates their clinical outcomes.No previously reported randomized or observational studies adequately assess the safety and efficacy of TAVR in an Asian population.The Asian TAVR registry is an international multicenter study that enrolled patients with aortic stenosis who underwent TAVR in Asian countries.In total, 848 patients with mean STS score of 5.2 3.8% were enrolled between March 2010 and September 2014 at 11 centers in 5 countries. The Edwards Sapien or Medtronic CoreValve was implanted in 64.7% and 35.3% of patients, respectively. The procedural success rate was 97.5%. The 30-day and 1-year mortality rates were 2.5% and 10.8%, respectively. There was no difference in 1-year mortality between devices (Sapien: 9.4%; CoreValve: 12.2%; log-rank p= 0.40). The rates of stroke, life-threatening bleeding, major vascular complications and acute kidney injury (stage 2 to 3) were 3.8%, 6.4%, 5.0% and 3.3%, respectively. Moderate or severe paravalvular leakage was significantly more common with the CoreValve than Sapien (14.4% vs. 7.3%; p= 0.001). According to the multivariate model, a higher STS score, lower body mass index, New York Heart Association functional class III-IV symptoms, diabetes mellitus, prior cerebrovascular accident, low mean gradient at baseline, and moderate or severe paravalvular leakage were significantly associated with reduced survival.Despite anatomical features of concern, the clinical outcomes of TAVR in our Asian population werefavorable in comparison with those of previously published trials and observational studies. (The Asian Transcatheter Aortic Valve Replacement Registry [Asian TAVR]; NCT02308150).

PubMed | Hamad Medical Corporation, University of Ulsan, New York Medical College and Cedars Sinai Medical Center
Type: | Journal: The international journal of cardiovascular imaging | Year: 2017

There are limited data regarding subclinical atherosclerosis in Middle Eastern countries. We aimed to describe and compare coronary computed tomographic angiography (CCTA) findings in Qatari native and South Asian migrants at increased risk of coronary artery disease (CAD).We performed CCTA in 251 consecutive volunteers (126 South Asian, 125 Qatari, mean age 50.07.3 years, 27.1% female) at increased risk of cardiovascular disease. Given differences in baseline risk factors, we employed propensity score matching to create a cohort of 162 subjects for comparative analyses. We compared CAD severity, extent, plaque morphology, adverse plaque characteristics, and quantitative measures of atherosclerotic burden in both subgroups.After matching, no CAD was seen in 58.0% of South Asians and 49.4% of Qataris (p=0.3), while obstructive CAD (50% luminal stenosis) was present in 40.7% of South Asians and 49.4% of Qataris (p=0.3). There was a high prevalence of adverse plaque characteristics in both ethnicities, particularly positive remodeling. South Asians had significantly smaller vessel and lumen volumes, but the percent aggregate plaque volumes were not significantly different (2.96.3% vs. 3.88.0%, p=0.4).In this first study of CCTA findings performed in a Middle Eastern country, we observed a high prevalence of obstructive CAD in a middle-aged cohort. There were no significant differences in CCTA findings between Qataris and South Asians after adjustment for clinical risk factors. Future studies are needed to identify patterns of coronary atherosclerosis by CCTA in non-European populations where cardiovascular disease is increasingly prevalent.

PubMed | University Utrecht, University of Ulsan, University of California at Los Angeles and Brigham and Women's Hospital
Type: Journal Article | Journal: Human molecular genetics | Year: 2016

Meta-analysis strategies have become critical to augment power of genome-wide association studies (GWAS). To reduce genotyping or sequencing cost, many studies today utilize shared controls, and these individuals can inadvertently overlap among multiple studies. If these overlapping individuals are not taken into account in meta-analysis, they can induce spurious associations. In this article, we propose a general framework for adjusting association statistics to account for overlapping subjects within a meta-analysis. The key idea of our method is to transform the covariance structure of the data, so it can be used in downstream analyses. As a result, the strategy is very flexible and allows a wide range of meta-analysis methods, such as the random effects model, to account for overlapping subjects. Using simulations and real datasets, we demonstrate that our method has utility in meta-analyses of GWAS, as well as in a multi-tissue mouse expression quantitative trait loci (eQTL) study where our method increases the number of discovered eQTL by up to 19% compared with existing methods.

PubMed | University of Ulsan
Type: Journal Article | Journal: The Annals of thoracic surgery | Year: 2016

Transannular patching (TAP) frequently accompanies primary repairs (PRs) in symptomatic neonates with tetralogy of Fallot (TOF). If a systemic-pulmonary shunt (SPS) facilitates the growth of the pulmonary valve annulus (PVA), patients with a marginally small PVA could benefit from a staged repair in terms of lowering the risk of TAP.Among 216 infants with TOF who underwent surgical intervention between January 2004 and December 2013, 29 infants underwent SPS with a subsequent repair (SPS group), whereas 187 infants received a PR (PR group). Median age and the Z-score of the PVA (PVA [Z]) at SPS were 32 days and-3.5, respectively. There was one late death and one follow-up loss after SPS, and preservation of the PVA was achieved on repair in 16 patients (16 of 29; 55%).Multiple regression analysis showed that performance of SPS was the only indicator of the increase in the PVA (Z) in the entire cohort (n= 216). On mixed linear regression, the PVA (Z) increased significantly after the placement of an SPS (-3.6+ 0.2*duration in months, p= 0.001), whereas the prerepair changes in the PVA (Z) were not statistically significant in the PR group (p= 0.7), with a significant intergroup difference (p < 0.001). Receiver operating characteristic curve analysis showed that placement of TAP is expected when the preshunt PVA (Z) is smaller than-4.2 (area under the curve: 0.82; 95% confidence interval: 0.62 to 1.00; sensitivity, 100%; specificity, 73%).SPS facilitates outgrowth of the PVA over somatic growth in patients with TOF. However, preservation of the PVA may not be achieved on staged repair if the initial PVA is too small.

PubMed | University of Ulsan
Type: Journal Article | Journal: British journal of anaesthesia | Year: 2015

Coronary computed tomographic angiography (coronary CT) is a non-invasive test for diagnosis of cardiac function. Coronary calcium scores determined by coronary CT are associated with cardiovascular risk factors. However, no studies have investigated the association between coronary calcium scores and cardiovascular complications after liver transplantation (LT). We therefore evaluated the utility of preoperative coronary calcium scores for predicting early postoperative cardiovascular complications in LT recipients.Between 2010 and 2012, 443 LT recipients were analysed retrospectively. Preoperative cardiovascular assessments, including coronary CT, were performed. A coronary calcium score >400 was defined as a positive finding. Predictive factors of early postoperative cardiovascular complications were evaluated by univariate and multivariate analyses. Major cardiovascular complications occurring during a period of 1 month after LT were noted.Of the 443 patients, 38 (8.6%) experienced one or more cardiovascular complications. Positive coronary CT findings were seen in 11 (2.5%) patients. In the multivariate analysis, a coronary calcium score >400 {odds ratio (OR)=4.62 [95% confidence interval (CI): 1.14-18.72], P=0.032} and female sex [OR=2.76 (1.37-5.57), P=0.005] were predictive of cardiovascular complications.A preoperative coronary calcium score of >400 predicted cardiovascular complications occurring 1 month after LT, suggesting that preoperative evaluation of coronary calcium scores could help predict early postoperative cardiovascular complications in LT recipients.

PubMed | University of Groningen, University of Ulsan, Northwestern University, Bobath Memorial Hospital and Purdue University
Type: Journal Article | Journal: Communication sciences & disorders (Seoul, Korea) | Year: 2015

Individuals with nonfluent agrammatic aphasia show impaired production and comprehension of time reference via verbal morphology. However, cross-linguistic findings to date suggest inconsistent evidence as to whether tense processing in general is impaired or time reference to the past is selectively difficult in this population. This study examined production and comprehension of time reference via verb morphology in Korean-speaking individuals with nonfluent aphasia.A group of 9 healthy controls and 8 individuals with nonfluent aphasia (5 for the production task) participated in the study. Sentence priming production and auditory sentence to picture matching tasks were used, parallel with the previous cross-linguistic experiments in English, Chinese, Turkish, and others.The participants with nonfluent aphasia showed different patterns of impairment in production and comprehension. In production, they were impaired in all time references with errors being dominated by substitution of incorrect time references and other morpho-phonologically well-formed errors, indicating a largely intact morphological affixation process. In comprehension, they showed selective impairment of the past, consistent with the cross-linguistic evidence from English, Chinese, Turkish, and others.The findings suggest that interpretation of past time reference poses particular difficulty in nonfluent aphasia irrespective of typological characteristics of languages; however, in production, language-specific morpho-semantic functions of verbal morphology may play a significant role in selective breakdowns of time reference.

PubMed | Pathology K.J.C. . and University of Ulsan
Type: Clinical Study | Journal: AJNR. American journal of neuroradiology | Year: 2015

Diagnostic test accuracy studies for ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy have shown inconclusive results due to their heterogenous study designs. Our aim was to compare the diagnostic accuracy of ultrasonography-guided fine-needle aspiration versus ultrasonography-guided core needle biopsy for detecting malignant tumors of the salivary gland and for the tissue-specific diagnosis of salivary gland tumors in a single tertiary hospital.This retrospective study was approved by our institutional review board and informed consent was waived. Four hundred twelve patients who underwent ultrasonography-guided fine-needle aspiration (n = 155) or ultrasonography-guided core needle biopsy (n = 257) with subsequent surgical confirmation or clinical follow-up were enrolled. We compared the diagnostic accuracy of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy regarding malignant salivary gland tumors and the correct tissue-specific diagnosis of benign and malignant tumors. We also tested the difference between these procedures according to the operators experience and lesion characteristics.The inconclusive rates of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy were 19% and 4%, respectively (P < .001). The overall accuracy of ultrasonography-guided core needle biopsy for diagnosing malignant tumors was significantly higher than that of ultrasonography-guided fine-needle aspiration (P = .024). The correct tissue-specific diagnosis rates of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy were 95% versus 97% for benign tumors (P = .648) and 67% versus 80% for malignant tumors (P = .310). Trainees showed significantly lower accuracy with ultrasonography-guided fine-needle aspiration than with ultrasonography-guided core needle biopsy for diagnosing malignant tumors (P = .021). There was no difference between the diagnostic accuracy of ultrasonography-guided fine-needle aspiration and ultrasonography-guided core needle biopsy according to the internal composition of the lesions. There were no complications requiring intervention or hospitalization in our patients.Ultrasonography-guided core needle biopsy is superior to ultrasonography-guided fine-needle aspiration in detecting and characterizing malignant tumors of the salivary gland and could emerge as the diagnostic method of choice for patients presenting with a salivary gland mass.

PubMed | McGill University, University of Ulsan, Denver Veterans Affairs Medical Center, National Institute for Health Development and 8 more.
Type: Journal Article | Journal: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America | Year: 2016

Medical treatment for multidrug-resistant (MDR)-tuberculosis is complex, toxic, and associated with poor outcomes. Surgical lung resection may be used as an adjunct to medical therapy, with the intent of reducing bacterial burden and improving cure rates. We conducted an individual patient data metaanalysis to evaluate the effectiveness of surgery as adjunctive therapy for MDR-tuberculosis.Individual patient data, was obtained from the authors of 26 cohort studies, identified from 3 systematic reviews of MDR-tuberculosis treatment. Data included the clinical characteristics and medical and surgical therapy of each patient. Primary analyses compared treatment success (cure and completion) to a combined outcome of failure, relapse, or death. The effects of all forms of resection surgery, pneumonectomy, and partial lung resection were evaluated.A total of 4238 patients from 18 surgical studies and 2193 patients from 8 nonsurgical studies were included. Pulmonary resection surgery was performed on 478 patients. Partial lung resection surgery was associated with improved treatment success (adjusted odds ratio [aOR], 3.0; 95% confidence interval [CI], 1.5-5.9; I(2)R, 11.8%), but pneumonectomy was not (aOR, 1.1; 95% CI, .6-2.3; I(2)R, 13.2%). Treatment success was more likely when surgery was performed after culture conversion than before conversion (aOR, 2.6; 95% CI, 0.9-7.1; I(2)R, 0.2%).Partial lung resection, but not pneumonectomy, was associated with improved treatment success among patients with MDR-tuberculosis. Although improved outcomes may reflect patient selection, partial lung resection surgery after culture conversion may improve treatment outcomes in patients who receive optimal medical therapy.

PubMed | Yonsei University and University of Ulsan
Type: | Journal: Artificial organs | Year: 2016

Decellularization is a proposed method of preparing nonautologous biological arterial vascular scaffolding; however, the fate of the supporting medial elastic fiber, which is important in preserving the vascular structural integrity, is uncertain. The influence of losartan on preserving the medial elastic fiber integrity in decellularized small diameter vascular conduits (SDVC) was investigated. Decellularized infrarenal abdominal aortic allografts were implanted in Sprague-Dawley rats treated either with (study rats, n=6) or without oral losartan (control rats, n=6) and graded 8 weeks later according to a remodeling scoring system (1-mild, 2-moderate, 3-severe) which we devised based on the intimal hyperplasia degree, morphologic changes, and elastic fiber fragmentation of the conduits. DAPI immunohistochemistry analysis was performed in 47 (25 decellularization only and 22 losartan treatment) cross-sectional slide specimens. The losartan versus decellularization only SDVC showed a significantly lower medial elastic fragmentation score (1.32 vs. 2.24, P < 0.001), superior medial layer preservation, and relatively more normal appearing intimal cellular morphology. The results suggested rats receiving decellularized SDVCs treated with losartan may yield superior medial layer elastic fiber preservation.

PubMed | University of Minnesota, Genzyme, North Ohio Heart Center, University of Ulsan and 13 more.
Type: Journal Article | Journal: Journal of medical genetics | Year: 2016

Agalsidase is a form of enzyme replacement therapy for Fabry disease, a genetic disorder characterised by low -galactosidase A activity, accumulation of glycosphingolipids and life-threatening cardiovascular, renal and cerebrovascular events. In clinical trials, agalsidase cleared glycolipid deposits from endothelial cells within 6months; clearance from other cell types required sustained treatment. We hypothesised that there might be a lag time to clinical benefit after initiating agalsidase treatment, and analysed the incidence of severe clinical events over time in patients receiving agalsidase .The incidence of severe clinical events (renal failure, cardiac events, stroke, death) was studied in 1044 adult patients (641 men, 403 women) enrolled in the Fabry Registry who received agalsidase (average dose 1mg/kg every 2weeks) for up to 5years.The incidence of all severe clinical events was 111 per 1000 person-years (95% CI 84 to 145) during the first 6months. After 6months, the incidence decreased and remained stable within the range of 40-58 events per 1000 patient-years. The largest decrease in incidence rates was among male patients and those aged 40years when agalsidase was initiated.Contrary to the expected increased incidence of severe clinical events with time, adult patients with Fabry disease had decreased incidence of severe clinical events after 6months treatment with agalsidase 1 mg/kg every 2weeks.NCT00196742.

PubMed | University of Kentucky, University of Ulsan, University of Michigan, University of Groningen and 3 more.
Type: Journal Article | Journal: PloS one | Year: 2016

The Continuing to Confront COPD International Patient Survey estimated the prevalence and burden of COPD across 12 countries. Using data from this survey we evaluated the economic impact of COPD.This cross-sectional, population-based survey questioned 4,343 subjects aged 40 years and older, fulfilling a case definition of COPD based on self-reported physician diagnosis or symptomatology. Direct cost measures were based on exacerbations of COPD (treated and those requiring emergency department visits and/or hospitalisation), contacts with healthcare professionals, and COPD medications. Indirect costs were calculated from work loss values using the Work Productivity and Activity Impairment scale. Combined direct and indirect costs estimated the total societal costs per patient.The annual direct costs of COPD ranged from $504 (South Korea) to $9,981 (USA), with inpatient hospitalisations (5 countries) and home oxygen therapy (3 countries) being the key drivers of direct costs. The proportion of patients completely prevented from working due to their COPD ranged from 6% (Italy) to 52% (USA and UK) with 8 countries reporting this to be 20%. Total societal costs per patient varied widely from $1,721 (Russia) to $30,826 (USA) but a consistent pattern across countries showed greater costs among those with increased burden of COPD (symptoms, health status and more severe disease) and a greater number of comorbidities.The economic burden of COPD is considerable across countries, and requires targeted resources to optimise COPD management encompassing the control of symptoms, prevention of exacerbations and effective treatment of comorbidities. Strategies to allow COPD patients to remain in work are important for addressing the substantial wider societal costs.

PubMed | Cardiovascular Research Foundation and University of Ulsan
Type: | Journal: Atherosclerosis | Year: 2016

We aimed to determine whether finite element analysis (FEA)-derived plaque structural stress (PSS) analysis can predict serial changes in atheroma volume, type, and tissue composition within a fibroatheroma-containing target segment.Overall, 210 patients (210 untreated coronary artery lesions) underwent serial (baseline and 12-month follow-up) grayscale- and virtual histology (VH)-intravascular ultrasound (IVUS). Baseline PSS was assessed at the minimal lumen and at the maximum necrotic core (NC) sites.Overall, there was a significant decrease in %NC volume. The highest PSS tertile was associated with a smaller on-statin reduction in %NC volume (-1.551.03% in the highest vs.-5.181.12% in the lowest tertile, p=0.025). Of the 115 lesions with baseline VH-thin cap fibroatheroma (TCFA), 36 (31%) showed persistent VH-TCFA at follow-up. Five of the 95 lesions with baseline thick-cap fibroatheroma evolved into VH-TCFA. Independent predictors of VH-TCFA at follow-up (including persistent and new VH-TCFAs) were diabetes mellitus (odds ratio [OR]=3.87, 95% CI=1.58-9.47), a large MLA (OR=1.39, 95% CI=1.10-1.75), a greater percent atheroma volume (OR=1.12, 95% CI=1.05-1.19), VH-TCFA at baseline (OR=8.01, 95% CI=2.73-23.50), and a higher superficial PSS at the maximum NC site (OR=1.02, 95% CI=1.00-1.03), (all p<0.05). Independent determinants of the serial change in %NC volume were high-sensitive C-reactive protein (=-2.79, 95% CI=-5.31 to-0.27), baseline %NC volume (=-0.70, 95% CI=-0.84 to-0.56), and superficial PSS at the maximum NC site (=0.05, 95% CI=0.01-0.08), (all p<0.05).An elevated PSS was more likely associated with an increase in atheroma volume, a smaller on-statin reduction in %NC volumes, and the presence of VH-TCFA at follow-up. Morphologic and hemodynamic assessment by utilizing VH-IVUS may help understand and predict atherosclerotic progression.

PubMed | Cardiovascular Research Foundation and University of Ulsan
Type: Journal Article | Journal: Journal of the American College of Cardiology | Year: 2016

How statins alter the natural course of coronary atherosclerosis with compositional changes remains unclear.This study aimed to determine the effect of statin therapy on modifying plaque composition.The STABLE (Statin and Atheroma Vulnerability Evaluation) prospective, single-center, double-blind, randomized study evaluated the effect of statins on functionally insignificant coronary stenoses. We randomly assigned 312 patients with a virtual histology (VH) intravascular ultrasound-defined fibroatheroma-containing index lesion to rosuvastatin 40 mg versus 10 mg (2:1 ratio). In 225 (72%) patients, grayscale- and VH-intravascular ultrasound were completed at baseline and 12 months. The primary endpoint was the change in VH-defined percent compositional volume within the target segment from baseline to follow-up in the per-protocol analysis set.Percent necrotic core (NC) volume within the target segment significantly decreased from 21.3 6.8% to 18.0 7.5% during 1-year follow-up, whereas the percent fibrofatty volume increased (11.7 5.8% vs. 14.8 9.3%; all p < 0.001). Percent fibrous (59.4 7.8% vs. 59.2 8.6%) and dense calcium (7.6 5.1% vs. 7.8 5.6%) volumes were unchanged. Frequencies of VH (55% vs. 29%) decreased significantly. Normalized total (202.9 72.3 mm(3) vs. 188.5 67.8 mm(3); p = 0.001) and percent (51.4 8.3% vs. 50.4 8.8%; p = 0.018) atheroma volumes decreased. Independent predictors of percent NC volume change were body mass index ( = 0.37; 95% confidence interval [CI]: 0.05 to 0.70), high sensitivity C-reactive protein ( = -3.16; 95% CI: -5.64 to -0.69), and baseline percent NC volume ( = -0.44; 95% CI: -0.68 to -0.19; all p < 0.05). VH-defined percent compositional volume changes in the rosuvastatin 40- and 10-mg groups were similar.Rosuvastatin reduced NC and plaque volume and decreased thin-cap fibroatheroma rate. There were no significant differences between high- versus moderate-intensity rosuvastatin. (Statin and Atheroma Vulnerability Evaluation [STABLE]; NCT00997880).

PubMed | Hospital Universitario La Paz, Institute Rotary Cancer Hospital, University of Ulsan, Saitama Cancer Center and 11 more.
Type: Journal Article | Journal: JAMA oncology | Year: 2016

Efficacious ERBB2 (formerly HER2 or HER2/neu)-directed treatments, in addition to trastuzumab and lapatinib, are needed.To determine whether neratinib, an irreversible pan-ERBB tyrosine kinase inhibitor, plus paclitaxel improves progression-free survival compared with trastuzumab plus paclitaxel in the first-line treatment of recurrent and/or metastatic ERBB2-positive breast cancer.In the randomized, controlled, open-label NEfERT-T trial conducted from August 2009 to December 2014 at 188 centers in 34 countries in Europe, Asia, Africa, and North America, 479 women with previously untreated recurrent and/or metastatic ERBB2-positive breast cancer were randomized to 1 of 2 treatment arms (neratinib-paclitaxel [n=242] or trastuzumab-paclitaxel [n=237]). Women with asymptomatic central nervous system metastases were eligible, and randomization was stratified by prior trastuzumab and lapatinib exposure, hormone-receptor status, and region.Women received neratinib (240 mg/d orally) or trastuzumab (4 mg/kg then 2 mg/kg weekly), each combined with paclitaxel (80 mg/m2 on days 1, 8, and 15 every 28 days). Primary prophylaxis for diarrhea was not mandatory.The primary outcome was progression-free survival. Secondary end points were response rate, clinical benefit rate, duration of response, frequency, and time to symptomatic and/or progressive central nervous system lesions, and safety.The intent-to-treat population comprised 479 women 18 years or older (neratinib-paclitaxel, n=242; trastuzumab-paclitaxel, n=237) randomized and stratified in their respective treatment arms by prior trastuzumab and lapatinib exposure, hormone-receptor status, and region. Median progression-free survival was 12.9 months (95% CI, 11.1-14.9) with neratinib-paclitaxel and 12.9 months (95% CI, 11.1-14.8) with trastuzumab-paclitaxel (hazard ratio [HR], 1.02; 95% CI, 0.81-1.27; P=.89). With neratinib-paclitaxel, the incidence of central nervous system recurrences was lower (relative risk, 0.48; 95% CI, 0.29-0.79; P=.002) and time to central nervous system metastases delayed (HR, 0.45; 95% CI, 0.26-0.78; P=.004). Common grade 3 to 4 adverse events were diarrhea (73 of 240 patients [30.4%] with neratinib-paclitaxel and 9 of 234 patients [3.8%] with trastuzumab-paclitaxel), neutropenia (31 patients [12.9%] vs 34 patients [14.5%]) and leukopenia (19 patients [7.9%] vs 25 patients [10.7%]); no grade 4 diarrhea was observed.In first-line ERBB2-positive metastatic breast cancer, neratinib-paclitaxel was not superior to trastuzumab-paclitaxel in terms of progression-free survival. In spite of similar overall efficacy, neratinib-paclitaxel may delay the onset and reduce the frequency of central nervous system progression, a finding that requires a larger study to confirm.clinicaltrials.gov Identifier: NCT00915018.

PubMed | Neurosurgery and. and University of Ulsan
Type: | Journal: Journal of neurosurgery | Year: 2016

Although extremely rare, retention of foreign bodies such as microcatheters or micro guidewires can occur during various neurovascular procedures due to gluing of the microcatheter tip or entanglement of the micro guidewire tip with intravascular devices. The authors have experienced 2 cases of irresolvable wire retention, one after flow diverter placement for a left cavernous internal carotid artery aneurysm and the other after intracranial stenting for acute basilar artery occlusion. The first patient presented 6 weeks after her procedure with right lung parenchymal hemorrhage due to direct piercing of the lung parenchyma after the retained wire fractured and migrated out of the aortic arch. The second patient presented 4 years after his procedure with pneumothorax due to migration of the fractured guidewire segment into the right thoracic cavity. In this report, the authors discuss the possible mechanisms of these unusual complications and how to prevent delayed consequences from a retained intravascular metallic wire.

PubMed | Yale University, University of Ulsan, Sungkyunkwan University and Seoul National Hospital
Type: Journal Article | Journal: Psychiatry investigation | Year: 2016

Lethality of the chosen method during a suicide attempt is a strong risk factor for completion of suicide. We examined whether annual changes in the pattern of suicide methods is related to annual changes in suicide rates among older adults in South Korea and Japan.We analyzed annual the World Health Organization data on rates and methods of suicide from 2000 to 2011 in South Korea and Japan.For Korean older adults, there was a significant positive correlation between suicide rate and the rate of hanging or the rate of jumping, and a significant negative correlation between suicide rate and the rate of poisoning. Among older adults in Japan, annual changes in the suicide rate and the pattern of suicide methods were less conspicuous, and no correlation was found between them.The results of the present study suggest that the increasing use of lethal suicide methods has contributed to the rise in suicide rates among older adults in South Korea. Targeted efforts to reduce the social acceptability and accessibility of lethal suicide methods might lead to lower suicide rate among older adults in South Korea.

PubMed | Korea University, University of Ulsan, Seoul National University, Sejong University and 2 more.
Type: Journal Article | Journal: Clinical infectious diseases : an official publication of the Infectious Diseases Society of America | Year: 2016

The largest outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV) outside the Middle East occurred in South Korea in 2015 and resulted in 186 laboratory-confirmed infections, including 36 (19%) deaths. Some hospitals were considered epicenters of infection and voluntarily shut down most of their operations after nearly half of all transmissions occurred in hospital settings. However, the ways that MERS-CoV is transmitted in healthcare settings are not well defined.We explored the possible contribution of contaminated hospital air and surfaces to MERS transmission by collecting air and swabbing environmental surfaces in 2 hospitals treating MERS-CoV patients. The samples were tested by viral culture with reverse transcription polymerase chain reaction (RT-PCR) and immunofluorescence assay (IFA) using MERS-CoV Spike antibody, and electron microscopy (EM).The presence of MERS-CoV was confirmed by RT-PCR of viral cultures of 4 of 7 air samples from 2 patients rooms, 1 patients restroom, and 1 common corridor. In addition, MERS-CoV was detected in 15 of 68 surface swabs by viral cultures. IFA on the cultures of the air and swab samples revealed the presence of MERS-CoV. EM images also revealed intact particles of MERS-CoV in viral cultures of the air and swab samples.These data provide experimental evidence for extensive viable MERS-CoV contamination of the air and surrounding materials in MERS outbreak units. Thus, our findings call for epidemiologic investigation of the possible scenarios for contact and airborne transmission, and raise concern regarding the adequacy of current infection control procedures.

PubMed | Chang Gung University, University of Ulsan, National Taiwan University Hospital, Seoul National University and 7 more.
Type: Clinical Trial, Phase II | Journal: JAMA oncology | Year: 2016

Continuing molecularly targeted treatment beyond disease progression in non-small-cell lung cancer (NSCLC) has appeared promising in retrospective analyses, highlighting the challenge to identify whether progression is the optimal time to switch treatment.To study the efficacy of first-line erlotinib therapy in patients with NSCLC with activating EGFR mutations and postprogression erlotinib therapy.ASPIRATION (Asian Pacific trial of Tarceva as first-line in EGFR mutation) was a phase 2, open-label, single-arm study conducted from 2011 to 2012 in 23 centers in Hong Kong, Korea, Taiwan, and Thailand of adults with stage IV, EGFR mutation-positive NSCLC, with ECOG performance status 0 to 2.Patients received erlotinib 150 mg/d orally until disease progression, after which erlotinib therapy could be continued at patient and/or investigator discretion.The primary end point was progression-free survival (PFS1; time to Response Evaluation Criteria in Solid Tumours 1.1 progression or death). Secondary end points included PFS2 (time to off-erlotinib progression if erlotinib therapy was extended beyond progression at patient and/or investigator discretion), objective response rate, disease control rate, overall survival, and safety. The use of plasma-based assessment of EGFR mutations was also investigated.Of 359 patients screened, 208 were enrolled. Median follow-up was 11.3 (95% CI, 10.9-13.0) months. Of the 207 intent-to-treat patients (62.3% female; median age, 60.8 [range, 28-89] y), 176 had a PFS1 event (171 progression and 5 deaths); of these, 78 discontinued and 93 continued erlotinib therapy following progression. Median PFS1 was 10.8 (95% CI, 9.2-11.1) months. Median PFS1 and PFS2 in the 93 continuing patients was 11.0 (95% CI, 9.2-11.1) and 14.1 (95% CI, 12.2-15.9) months, respectively. Median PFS1 and PFS2 was 11.0 (95% CI, 9.3-12.0) and 14.9 (95% CI, 12.2-17.2) months in patients with exon 19 deletions or L585R mutations. Overall response rate was 66.2%; disease control rate was 82.6%. Median overall survival was 31.0 months (95% CI, 27.3 months to not reached). In the safety population (n = 207) serious adverse events were reported in 27.1%, with events of at least grade 3 experienced by 50.2%. Sensitivity and specificity of plasma-based EGFR mutation analysis was 77% and 92%, respectively.ASPIRATION supports the efficacy of first-line erlotinib therapy in patients with EGFR mutation-positive NSCLC and that treatment beyond progression is feasible and may delay salvage therapy in selected patients.clinicaltrials.gov Identifier: NCT01310036.

PubMed | University of Ulsan, Korea Institute of Science and Technology, Gyeongnam National University of Science and Technology, Gachon University and 3 more.
Type: Journal Article | Journal: Journal of agricultural and food chemistry | Year: 2016

The effects of a red raspberry component, sanguiin H-6 (SH-6), on the induction of apoptosis and the related signaling pathways in A2780 human ovarian carcinoma cells were investigated. SH-6 caused an antiproliferative effect and a severe morphological change resembling that of apoptotic cell death but no effect on the cancer cell cycle arrest. In addition, SH-6 induced an early apoptotic effect and activation of caspases as well as the cleavage of PARP, which is a hallmark of apoptosis. The early apoptotic percentages of A2780 cells exposed to 20 and 40 M SH-6 were 35.39 and 41.76, respectively. Also, SH-6 caused the activation of mitogen-activated protein kinases (MAPKs), especially p38, and the increase of truncated p15/BID. These results in the present study suggest that the apoptosis of A2780 human ovarian carcinoma cells by SH-6 is mediated by the MAPK p38 and a caspase-8-dependent BID cleavage pathway.

PubMed | The Royal Marsden NHS Foundation Trust, University of Leipzig, University of Ulsan, University of Houston and 9 more.
Type: Journal Article | Journal: Journal of clinical oncology : official journal of the American Society of Clinical Oncology | Year: 2017

4 Background: Sorafenib, an orally active inhibitor of VEGFR1-3 and Raf kinases, has shown promising clinical activity in single-arm phase II studies in radioactive iodine (RAI)-refractory differentiated thyroid cancer (DTC). The double-blind, randomized, multicenter phase III DECISION trial examined sorafenib efficacy and safety vs placebo in patients with progressive RAI-refractory DTC.Patients with locally advanced/metastatic RAI-refractory DTC who progressed in the preceding 14 months were randomized 1:1 to sorafenib 400 mg bid po or placebo. Placebo patients were allowed to receive sorafenib open-label upon progression. The primary endpoint was progression-free survival (PFS) assessed every 8 wks by independent radiologic review using modified RECIST 1.0 and analyzed by stratified log-rank statistics at = 0.01 (one-sided). Secondary endpoints included overall survival (OS), response rate (RR; complete + partial response [PR]), and safety.A total of 417 patients were randomized (207 to sorafenib and 210 to placebo); median age 63 yr, 52% female. Tumor histology by independent assessment was 57% papillary, 25% follicular, and 10% poorly differentiated. 96% of patients had metastatic disease; the most common target lesions were lung (71%), lymph node (40%), and bone (14%). The primary endpoint was met: median PFS 10.8 months (sorafenib) vs 5.8 months (placebo); HR 0.58, 95% CI 0.45-0.75, p<0.0001. Median OS has not been reached in either arm; 70% of placebo patients started open-label sorafenib. RR (all PRs) in the sorafenib vs placebo arms was 12.2% and 0.5% (p<0.0001) and stable disease 6 months was 42% and 33%, respectively. The most common any-grade treatment-emergent adverse events in the sorafenib arm included hand-foot skin reaction, diarrhea, alopecia, rash/desquamation, fatigue, weight loss and hypertension. One death in each arm was attributed to study drug.Sorafenib significantly improved PFS compared with placebo in patients with progressive RAI-refractory DTC. Tolerability was consistent with the known sorafenib safety profile.NCT00895674.

PubMed | World Health Organization, University of Ulsan, National Cancer Center, Seoul National University and 4 more.
Type: | Journal: BMC cancer | Year: 2016

Breast and ovarian cancers are predominant female cancers with increasing prevalence. The purpose of this study was to estimate the population attributable risks (PARs) of breast and ovarian cancer occurrence based on the relative risks (RRs) of modifiable reproductive factors and population-specific exposure prevalence.The PAR was calculated by using the 1990 standardized prevalence rates, the 2010 national cancer incidence with a 20 year lag period, the meta-analyzed RRs from studies conducted in the Korean population for breast cancer, and the meta-analyzed RRs from a Korean epithelial ovarian cancer study and a prior meta-analysis, and ovarian cancer cohort results up to 2012. For oral contraceptive and hormone replacement therapy use, we did not consider lag period.The summary PARs for modifiable reproductive factors were 16.7% (95% CI 15.8-17.6) for breast cancer (2404 cases) and 81.9% (95% CI 55.0-100.0) for ovarian cancer (1579 cases). The modifiable reproductive factors included pregnancy/age at first birth (8.0%), total period of breastfeeding (3.1%), oral contraceptive use (5.3%), and hormone replacement therapy use (0.3%) for breast cancer and included breastfeeding experience (2.9%), pregnancy (1.2%), tubal ligation (24.5%), and oral contraceptive use (53.3%) for ovarian cancer.Despite inherent uncertainties in the risk factors for breast and ovarian cancers, we suggest that appropriate long-term control of modifiable reproductive factors could reduce breast and ovarian cancer incidences and their related burdens by 16.7% and 81.9%, respectively.

PubMed | Nordic Bioscience A S, University of Ulsan, Reykjavik University, Garvan Institute of Medical Research and 4 more.
Type: | Journal: Nature communications | Year: 2016

Bone mineral density (BMD) is a measure of osteoporosis and is useful in evaluating the risk of fracture. In a genome-wide association study of BMD among 20,100 Icelanders, with follow-up in 10,091 subjects of European and East-Asian descent, we found a new BMD locus that harbours the PTCH1 gene, represented by rs28377268 (freq. 11.4-22.6%) that associates with reduced spine BMD (P=1.0 10(-11), =-0.09). We also identified a new spine BMD signal in RSPO3, rs577721086 (freq. 6.8%), that associates with increased spine BMD (P=6.6 10(-10), =0.14). Importantly, both variants associate with osteoporotic fractures and affect expression of the PTCH1 and RSPO3 genes that is in line with their influence on BMD and known biological function of these genes. Additional new BMD signals were also found at the AXIN1 and SOST loci and a new lead SNP at the EN1 locus.

PubMed | University of Ulsan and Asan Medical Center
Type: Journal Article | Journal: PloS one | Year: 2017

The purpose of this study was to determine if preoperative quantitative computed tomography (CT) features including texture and histogram analysis measurements are associated with tumor recurrence in patients with surgically resected adenocarcinoma of the lung.The study included 194 patients with surgically resected lung adenocarcinoma who underwent preoperative CT between January 2013 and December 2013. Quantitative CT feature analysis of the lung adenocarcinomas were performed using in-house software based on plug-in package for ImageJ. Ten quantitative features demonstrating the tumor size, attenuation, shape and texture were extracted. The CT parameters obtained from 1-mm and 5-mm data were compared using intraclass correlation coefficients. Univariate and multivariable logistic regression methods were used to investigate the association between tumor recurrence and preoperative CT findings.The 1-mm and 5-mm data were highly correlated in terms of diameter, perimeter, area, mean attenuation and entropy. Circularity and aspect ratio were moderately correlated. However, skewness and kurtosis were poorly correlated. Multivariable logistic regression analysis revealed that area (odds ratio [OR], 1.002 for each 1-mm2 increase; P = 0.003) and mean attenuation (OR, 1.005 for each 1.0-Hounsfield unit increase; P = 0.022) were independently associated with recurrence. The receiver operating curves using these two independent predictive factors showed high diagnostic performance in predicting recurrence (C-index = 0.81, respectively).Tumor area and mean attenuation are independently associated with recurrence in patients with surgically resected adenocarcinoma of the lung.

PubMed | University of Ulsan, University of Houston, University of Southern Denmark, Hospital Universitario Marques Of Valdecilla and 16 more.
Type: Journal Article | Journal: Aging | Year: 2016

The role of p53 family member p63 in oncogenesis is the subject of controversy. Limited research has been done on the clinical implications of p63 expression in diffuse large B-cell lymphoma (DLBCL). In this study, we assessed p63 expression in de novo DLBCL samples (n=795) by immunohistochemistry with a pan-p63-monoclonal antibody and correlated it with other clinicopathologic factors and clinical outcomes. p63 expression was observed in 42.5% of DLBCL, did not correlate with p53 levels, but correlated with p21, MDM2, p16INK4A, Ki-67, Bcl-6, IRF4/MUM-1 and CD30 expression, REL gains, and BCL6 translocation. p63 was an independent favorable prognostic factor in DLBCL, which was most significant in patients with International Prognostic Index (IPI) >2, and in activated-B-cell-like DLBCL patients with wide- type TP53. The prognostic impact in germinal-center-B-cell-like DLBCL was not apparent, which was likely due to the association of p63 expression with high-risk IPI, and potential presence of Np63 isoform in TP63 rearranged patients (a mere speculation). Gene expression profiling suggested that p63 has both overlapping and distinct functions compared with p53, and that p63 and mutated p53 antagonize each other. In summary, p63 has p53-like and p53-independent functions and favorable prognostic impact, however this protective effect can be abolished by TP53 mutations.

PubMed | Gundersen Lutheran Health System, Taizhou University, University of Ulsan, University of Houston and 16 more.
Type: Journal Article | Journal: Oncotarget | Year: 2015

Abnormal expression of the chemokine receptor CXCR4 plays an essential role in tumor cell dissemination and disease progression. However, the significance of CXCR4 overexpression in de novo diffuse large B cell lymphoma (DLBCL) is unknown. In 743 patients with de novo diffuse large B cell lymphoma (DLBCL) who received standard Rituximab-CHOP immunochemotherapy, we assessed the expression of CXCR4 and dissected its prognostic significance in various DLBCL subsets. Our results showed that CXCR4+ patients was associated with male, bulky tumor, high Ki-67 index, activated B-cell-like (ABC) subtype, and Myc, Bcl-2 or p53 overexpression. Moreover, CXCR4+ was an independent factor predicting poorer progression-free survival in germinal-center B-cell-like (GCB)-DLBCL, but not in ABC-DLBCL; and in patients with an IPI of 2, but not in those with an IPI>2. The lack of prognostic significance of CXCR4 in ABC-DLBCL was likely due to the activation of p53 tumor suppressor attenuating CXCR4 signaling. Furthermore, concurrent CXCR4+ and BCL2 translocation showed dismal outcomes resembling but independent of MYC/BCL2 double-hit DLBCL. Gene expression profiling suggested that alterations in the tumor microenvironment and immune responses, increased tumor proliferation and survival, and the dissemination of CXCR4+ tumor cells to distant organs or tissues were underlying molecular mechanisms responsible for the CXCR4+ associated poor prognosis.

PubMed | Ajou University, Korea University, University of Ulsan, Seoul National University and 3 more.
Type: | Journal: Infection, genetics and evolution : journal of molecular epidemiology and evolutionary genetics in infectious diseases | Year: 2015

A recent genome-wide association study (GWAS) for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) identified two loci (rs7574865 in STAT4 and rs9275319 in HLA-DQ) in a Chinese population. We attempted to replicate the associations between the two SNP loci and the risk of HCC in a Korean population. The rs7574865 in STAT4 and rs9275319 in HLA-DQ were genotyped in a total of 3838 Korean subjects composed of 287 HBV-related hepatocellular carcinoma patients, 671 chronic hepatitis B virus (CHB) patients, and 2880 population controls using TaqMan genotyping assay. Gene expression was measured by microarray. A logistic regression analysis revealed that rs7574865 in STAT4 and rs9275319 in HLA-DQ were associated with the risk of CHB (OR = 1.25, P = 0.0002 and OR = 1.57, P= 1.44 10(-10), respectively). However, these loci were no association with the risk of HBV-related HCC among CHB patients. In the gene expression analyses, although no significant differences in mRNA expression of nearby genes according to genotypes were detected, a significantly decreased mRNA expression in HCC subjects was observed in STAT4, HLA-DQA1, and HLA-DQB1. Although the genetic effects of two HCC susceptibility loci were not replicated, the two loci were found to exert susceptibility effects on the risk of CHB in a Korean population. In addition, the decreased mRNA expression of STAT4, HLA-DQA1, and HLA-DQB1 in HCC tissue might provide a clue to understanding their role in the progression to HCC.

PubMed | The Royal Marsden NHS Foundation Trust, Martin Luther University of Halle Wittenberg, University of Ulsan, University of Oslo and 9 more.
Type: Journal Article | Journal: International journal of cancer | Year: 2016

Limited data are available on the efficacy of anti-IGF-1R agents in KRAS mutant colorectal cancer (CRC). We analysed the outcome of 69 chemorefractory, KRAS exon 2 mutant CRC patients who were enrolled in a double-blind, randomised, phase II/III study of irinotecan and cetuximab plus dalotuzumab 10 mg/kg once weekly (arm A), dalotuzumab 7.5 mg/kg every second week (arm B) or placebo (arm C). Objective response rate (5.6% vs. 3.1% vs. 4.8%), median progression-free survival (2.7 vs. 2.6 vs. 1.4 months) and overall survival (7.8 vs. 10.3 vs. 7.8 months) were not statistically significantly different between treatment groups. Most common grade 3 treatment-related toxicities included neutropenia, diarrhoea, hyperglycaemia, fatigue and dermatitis acneiform. Expression of IGF-1R, IGF-1, IGF-2 and EREG by quantitative real-time polymerase chain reaction was assessed in 351 patients from the same study with available data on KRAS exon 2 mutational status. Median cycle threshold values for all biomarkers were significantly lower (i.e., higher expression, p<0.05) among patients with KRAS wild-type compared to those with KRAS exon 2 mutant tumours. No significant changes were found according to location of the primary tumour with only a trend towards lower expression of IGF-1 in colon compared to rectal cancers (p=0.06). Albeit limited by the small sample size, this study does not appear to support a potential role for anti-IGF-1R agents in KRAS exon 2 mutant CRC. Data on IGF-1R, IGF-1 and IGF-2 expression here reported may be useful for patient stratification in future trials with inhibitors of the IGF pathway.

PubMed | Dong - A University, University of Ulsan, Neuroscience Center, Seoul National University and 4 more.
Type: Journal Article | Journal: Acta neurologica Scandinavica | Year: 2016

Ethnic diversity between different populations may affect treatment safety and efficacy.A subanalysis to a global trial (study 326) was carried out to ascertain the safety and efficacy of donepezil 23 mg/day compared with donepezil 10 mg/day in Asian patients with moderate-to-severe Alzheimers disease. Changes in cognition and global functioning were measured by the Severe Impairment Battery (SIB) and Clinicians Interview-Based Impression of Change Plus Caregiver Input (CIBIC-Plus), respectively, at week 24.Cognitive improvement measured by SIB score was greater with donepezil 23 mg than with donepezil 10 mg (+1.36 vs -1.56]; difference, 2.92). There was no difference between the groups in global function measured by the CIBIC-Plus (3.94 and 3.95, respectively). Overall, 119 patients (82.1%) receiving donepezil 23 mg and 56 (71.8%) receiving donepezil 10 mg experienced 1 treatment emergent adverse events (TEAEs). In the donepezil 23 mg group, the incidence of TEAEs was higher among patients of lower weight (<55 kg) at baseline than in those of higher weight (64 of 75 patients [85.3%] vs 55 of 70 patients [78.5%]).The benefits and risks associated with donepezil 23 mg in Asian patients are comparable to those of the global study population.

PubMed | University of Ulsan, Seoul National University, Keimyung University, Inje University and 3 more.
Type: | Journal: JACC. Cardiovascular imaging | Year: 2016

This study sought to investigate the impact of longitudinal lesion geometry on the location of plaque rupture and clinical presentation and its mechanism.The relationships among lesion geometry, external hemodynamic forces acting on the plaque, location of plaque rupture, and clinical presentation have not been comprehensively investigated.This study enrolled 125 patients with plaque rupture documented by intravascular ultrasound. Longitudinal locations of plaque rupture were identified and categorized by intravascular ultrasound. Patients clinical presentations and TIMI (Thrombolysis in Myocardial Infarction) flow grade in an initial angiogram were compared according to the location of plaque rupture. Longitudinal lesion asymmetry was quantitatively assessed by the luminal radius change over the segment length (radius gradient [RG]). Lesions with a steeper radius change in the upstream segment compared with the downstream segment (RGOn the basis of the site of maximum rupture aperture, 56.0%, 16.0%, and 28.0% of the patients had upstream, minimal lumen area, and downstream rupture, respectively. Patients with upstream rupture more frequently presented with ST-segment elevation myocardial infarction (45.7%, 40.0%, 22.9%; p= 0.030) and with TIMI flow grade<3 (32.9%, 20.0%, 17.1%; p= 0.042). According to the ratio of upstream and downstream RG, 69.5% of lesions were classified as upstream-dominant lesions, and 30.5% were classified as downstream-dominant lesions. Among the 66 upstream-dominant lesions, 65 cases (98.5%) had upstream rupture, and the RG ratio (RGBoth clinical presentation and degree of flow limitation were associated with the location of plaque rupture. Longitudinal lesion asymmetry assessed by RG, which can affect regional distribution of hemodynamic stress, was associated with the location of rupture and with clinical presentation.

PubMed | Cardiovascular Research Foundation and University of Ulsan
Type: Journal Article | Journal: Catheterization and cardiovascular interventions : official journal of the Society for Cardiac Angiography & Interventions | Year: 2016

Although attenuated plaque is a marker for plaque vulnerability, the quantification and its implication have not been known.Multimodality pre-procedural imaging using grayscale intravascular ultrasound (IVUS), virtual histology-IVUS (VH-IVUS), and optical coherence tomography (OCT) were performed in 115 coronary lesions with diameter stenosis (DS) >30% and plaque burden 50% and compared the diagnostic accuracies for detecting thin-cap fibroatheromas (TCFA).A maximal arc of attenuation (40 MHz IVUS) 29.0 was the cutoff for predicting VH-TCFA (sensitivity 74%, specificity 66%); and OCT-TCFA (sensitivity 89%, specificity 64%), while a maximal arc attenuation 29.0 (20MHz IVUS) showed a poor sensitivity for predicting TCFA. Compared to the lesions with an arc of attenuation <30 as a rough cutoff value, the lesions with a maximum arc of attenuation 30 (40 MHz) were associated with more severe (smaller angiographic minimum lumen diameter and greater DS, smaller IVUS-MLA and a larger plaque burden) and had more unstable lesion characteristics: (1) larger remodeling index and more plaque ruptures (grayscale IVUS); (2) greater %necrotic core and more VH-TCFAs (VH-IVUS); and (3) more lipid, macrophages, cholesterol crystals, and microchannels; thinner fibrous caps; and more OCT-TCFAs, OCT-detected plaque ruptures, and red and white thrombi (OCT). Among 58 patients treated with stent implantation, postintervention peak CK-MB was higher in patients with the maximal attenuation 30 compared to those without (median 2.7 ng/ml [IQR 0.9-18.7 ng/ml] vs. median 0.9 ng/ml [IQR 0.7-2.1 ng/ml], P=0.012).Attenuated plaque with a maximal attenuation 30 vs. <30 (40 MHz, but not 20 MHz IVUS) were more likely to be associated with unstable lesion morphology that may contribute to the immediate poststenting CK-MB elevation. 2016 Wiley Periodicals, Inc.

PubMed | Shinshu University, University of Houston, Inje University, Stanford University and 21 more.
Type: Evaluation Studies | Journal: The Lancet. Oncology | Year: 2016

The clinical outcome of extranodal natural killer T-cell lymphoma (ENKTL) has improved substantially as a result of new treatment strategies with non-anthracycline-based chemotherapies and upfront use of concurrent chemoradiotherapy or radiotherapy. A new prognostic model based on the outcomes obtained with these contemporary treatments was warranted.We did a retrospective study of patients with newly diagnosed ENKTL without any previous treatment history for the disease who were given non-anthracycline-based chemotherapies with or without upfront concurrent chemoradiotherapy or radiotherapy with curative intent. A prognostic model to predict overall survival and progression-free survival on the basis of pretreatment clinical and laboratory characteristics was developed by filling a multivariable model on the basis of the dataset with complete data for the selected risk factors for an unbiased prediction model. The final model was applied to the patients who had complete data for the selected risk factors. We did a validation analysis of the prognostic model in an independent cohort.We did multivariate analyses of 527 patients who were included from 38 hospitals in 11 countries in the training cohort. Analyses showed that age greater than 60 years, stage III or IV disease, distant lymph-node involvement, and non-nasal type disease were significantly associated with overall survival and progression-free survival. We used these data as the basis for the prognostic index of natural killer lymphoma (PINK), in which patients are stratified into low-risk (no risk factors), intermediate-risk (one risk factor), or high-risk (two or more risk factors) groups, which were associated with 3-year overall survival of 81% (95% CI 75-86), 62% (55-70), and 25% (20-34), respectively. In the 328 patients with data for Epstein-Barr virus DNA, a detectable viral DNA titre was an independent prognostic factor for overall survival. When these data were added to PINK as the basis for another prognostic index (PINK-E)-which had similar low-risk (zero or one risk factor), intermediate-risk (two risk factors), and high-risk (three or more risk factors) categories-significant associations with overall survival were noted (81% [95% CI 75-87%], 55% (44-66), and 28% (18-40%), respectively). These results were validated and confirmed in an independent cohort, although the PINK-E model was only significantly associated with the high-risk group compared with the low-risk group.PINK and PINK-E are new prognostic models that can be used to develop risk-adapted treatment approaches for patients with ENKTL being treated in the contemporary era of non-anthracycline-based therapy.Samsung Biomedical Research Institute.

PubMed | Gundersen Lutheran Health System, University of Ulsan, University of Houston, University of Southern Denmark and 16 more.
Type: Journal Article | Journal: Blood | Year: 2016

CD37 (tetraspanin TSPAN26) is a B-cell surface antigen widely expressed on mature B cells. CD37 is involved in immune regulation and tumor suppression but its function has not been fully elucidated. We assessed CD37 expression in de novo diffuse large B-cell lymphoma (DLBCL), and investigated its clinical and biologic significance in 773 patients treated with rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and 231 patients treated with CHOP. We found that CD37 loss (CD37

PubMed | University of Punjab, University of Ulsan, University of Kiel, University of Rostock and 6 more.
Type: Journal Article | Journal: Journal of neurology | Year: 2016

Specific mutations in COL6A3 have recently been reported as the cause of isolated recessive dystonia, which is a rare movement disorder. In all patients, at least one mutation was located in Exons 41 and 42. In an attempt to replicate these findings, we assessed by direct sequencing the frequency of rare variants in Exons 41 and 42 of COL6A3 in 955 patients with isolated or combined dystonia or with another movement disorder with dystonic features. We identified nine heterozygous carriers of rare variants including five different missense mutations and an extremely rare synonymous variant. In these nine patients, we sequenced the remaining 41 coding exons of COL6A3 to test for a second mutation in the compound heterozygous state. In only one of them, a second rare variant was identified (Thr732Met + Pro3082Arg). Of note, this patient had been diagnosed with Parkinsons disease (with dystonic posturing) due to homozygous PINK1 mutations. The COL6A3 mutations clearly did not segregate with the disease in the four affected siblings of this family. Further, there was no indication for a disease-modifying effect of the COL6A3 mutations since disease severity or age at onset did not correlate with the number of COL6A3 mutated alleles in this family. In conjunction with the relatively high frequency of homozygous carriers of reported mutations in publically available databases, our data call a causal role for variants in COL6A3 in isolated dystonia into question.

PubMed | Sultanah Aminah Hospital, Phramongkutklao Hospital, National University Hospital Singapore, University of Ulsan and 13 more.
Type: Journal Article | Journal: Intensive care medicine | Year: 2016

To compare the attitudes of physicians towards withholding and withdrawing life-sustaining treatments in intensive care units (ICUs) in low-middle-income Asian countries and regions with those in high-income ones, and to explore differences in the role of families and surrogates, legal risks, and financial considerations between these countries and regions.Questionnaire study conducted in May-December 2012 on 847 physicians from 255 ICUs in 10 low-middle-income countries and regions according to the World Banks classification, and 618 physicians from 211 ICUs in six high-income countries and regions.After we accounted for personal, ICU, and hospital characteristics on multivariable analyses using generalised linear mixed models, physicians from low-middle-income countries and regions were less likely to limit cardiopulmonary resuscitation, mechanical ventilation, vasopressors and inotropes, tracheostomy and haemodialysis than those from high-income countries and regions. They were more likely to involve families in end-of-life care discussions and to perceive legal risks with limitation of life-sustaining treatments and do-not-resuscitate orders. Nonetheless, they were also more likely to accede to families requests to withdraw life-sustaining treatments in a patient with an otherwise reasonable chance of survival on financial grounds in a case scenario (adjusted odds ratio 5.05, 95% confidence interval 2.69-9.51, P<0.001).Significant differences in ICU physicians self-reported practice of limiting life-sustaining treatments, the role of families and surrogates, perception of legal risks and financial considerations exist between low-middle-income and high-income Asian countries and regions.

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