Lee S.,Kyungpook National University |
Kim Y.K.,Kyungpook National University |
Shin T.-Y.,Woosuk University |
Kim S.-H.,Kyungpook National University
Neurotoxicity Research | Year: 2013
Bisphenol AF (BPAF), a newly introduced chemical structurally related to bisphenol A, is used extensively in fluoroelastomers and polyesters, and has been known to induce estrogen-dependent responses. However, the toxicity of BPAF is largely unknown except for its endocrine-related effects. In this study, we investigated the neurotoxicity of BPAF and underlying mechanisms of action using hippocampal cell line (HT-22) and mouse primary neuronal cells. We found that BPAF induced apoptosis in both HT-22 and primary neuronal cells. In order to clarify the underlying mechanisms of BPAF-induced apoptosis, various signaling molecules were evaluated. BPAF increased the level of intracellular calcium, followed by the generation of reactive oxygen species (ROS). BPAF upregulated the phosphorylation of mitogen-activated protein kinase: extracellular signal-regulated kinase, p38 and c-Jun N-terminal kinase (JNK), and nuclear translocation of nuclear factor-κB. Using specific inhibitors, we confirmed that calcium, ROS, p38, and JNK mediated the BPAF-induced apoptosis. In addition, BPAF inhibited microglial activation in a microglia/neuroblastoma coculture model by the reduction of nitric oxide production. We found that BPAF interrupted the normal physiologic functions of microglia at non-toxic levels. Taken together, our results suggest that BPAF, the substitute of BPA, also have neurotoxic properties. © 2012 Springer Science+Business Media, LLC.
Park S.D.,Woosuk University |
Yu S.H.,Gwang ju Trauma Center
Journal of Physical Therapy Science | Year: 2015
[Purpose] This study examined Nordic walking as an exercise intervention for the elderly with depression. [Subjects] Twenty-four patients who were diagnosed with depression were randomly selected and divided into two groups, an experimental group which performed Nordic walking, and a control group, which performed normal walking. [Methods] Both groups practiced their respective walking exercise for 50 minutes per day, three times a week for eight weeks. To compare the effects of the intervention, psychological factors using the Beck depression inventory and sleep quality was assessed using the Korean version Pittsburgh sleep quality index. Skeletal muscle mass, fat free mass, body mass index, body fat percentage, and basal metabolism were estimated three times by a body composition analyzer, before the intervention, four weeks after the intervention, and eight weeks after the intervention. [Results] There was a significant difference in depression with a main effect of time in both groups. There was also a significant difference in sleep in over time and interaction. The differences over time between the two groups were significant for depression, sleep, and skeletal muscle mass. [Conclusion] The results suggests that Nordic walking has a positive effect on depression and sleeping disorders of the elderly, suggesting that Nordic walking based exercise programs should be developed for the elderly who suffer from depression or a sleeping disorder. © 2015 The Society of Physical Therapy Science.
Xu W.,Woosuk University |
Lee M.-K.,Woosuk University
Journal of Pharmaceutical Investigation | Year: 2015
Solid lipid nanoparticles (SLNs) and nanostructured lipid carriers (NLCs) were prepared as delivery system for water-insoluble anticancer agent, paclitaxel (PTX). The dispersion of SLNs was consisted of 5 % w/w tristearin, 3.75 % w/w egg phosphatidylcholine (egg PC) and 1 % w/w polysorbate 80 in water. NLCs were prepared using the same composition as SLNs except that 10 % of the solid lipid was replaced by triolein. PTX was incorporated into SLNs and NLCs to attain 0.025 % w/w in the dispersion. The particle size of the prepared SLNs and NLCs were 167.9 ± 21.3 and 121.9 ± 28.3 nm, respectively, and slightly increased to 239.1 ± 32.6 and 183.6 ± 36.2 nm by PTX incorporation. PTX incorporation also increased polydispersity index suggesting broader size distribution compared to that for empty particles. SLNs and NLCs showed sustained release of PTX in cell culture media containing 10 % fetal bovine serum at 37 °C compared to the commercial micellar formulation consisted of Cremophor EL and ethanol. PTX in SLNs and NLCs showed comparable cytotoxicity to the commercial formulation and free PTX against human breast cancer cell line, MCF-7. On the contrary, PTX in SLNs and NLCs showed higher anticancer activity against multidrug resistant (MDR) cancer cell line, MCF-7/ADR, compared to the free PTX delivered in DMSO, which indicates that both SLNs and NLCs would be effective carriers to avoid efflux pump expressed in MDR cancer cells. In conclusion, the SLNs and NLCs prepared in the present study showed similar characteristics each other and both can be used as effective delivery system for PTX. © 2015, The Korean Society of Pharmaceutical Sciences and Technology.
Cha D.S.,Woosuk University |
Eun J.S.,Woosuk University |
Jeon H.,Woosuk University
Journal of Ethnopharmacology | Year: 2011
Aim of the study: The leaves of Eriobotrya japonica Lindl. have been widely used as a traditional medicine for the treatment of many diseases including coughs and asthma. The present study was designed to validate the anti-inflammatory and antinociceptive properties of the n-BuOH fraction of E. japonica (LEJ) leaves. Materials and methods: The anti-inflammatory properties of LEJ were studied using IFN-γ/LPS activated murine peritoneal macrophage model. The antinociceptive effects of LEJ were assessed using experimental models of pain, including thermal nociception methods, such as the tail immersion test and the hotplate test, and chemical nociception induced by intraperitoneal acetic acid and subplantar formalin in mice. To examine the possible connection of the opioid receptor to the antinociceptive activity of LEJ, we performed a combination test with naloxone, a nonselective opioid receptor antagonist. Results: In the IFN-γ and LPS-activated murine peritoneal macrophage model, LEJ suppressed NO production and iNOS expression via down-regulation of NF-κB activation. It also attenuated the expression of COX-2 and the secretion of pro-inflammatory cytokines like TNF-α and IL-6. Moreover, LEJ also demonstrated strong and dose-dependent antinociceptive activity compared to tramadol and indomethacin in various experimental pain models. In a combination test using naloxone, diminished analgesic activities of LEJ were observed, indicating that the antinociceptive activity of LEJ is connected with the opioid receptor. Conclusions: The results indicate that LEJ had potent inhibitory effects on the inflammatory mediators including nitric oxide, iNOS, COX-2, TNF-α and IL-6 via the attenuation of NF-κB translocation to the nucleus. LEJ also showed excellent antinociceptive activity in both central and peripheral mechanism as a weak opioid agonist. Based on these results, LEJ may possibly be used as an anti-inflammatory and an analgesic agent for the treatment of pains and inflammatory diseases. © 2010 Elsevier Ireland Ltd.
Bae J.,Korea Institute for Advanced Study |
Hwang W.-Y.,Chonnam National University |
Han Y.-D.,Woosuk University
Physical Review Letters | Year: 2011
We provide a general framework of utilizing the no-signaling principle in derivation of the guessing probability in the minimum-error quantum state discrimination. We show that, remarkably, the guessing probability can be determined by the no-signaling principle. This is shown by proving that, in the semidefinite programing for the discrimination, the optimality condition corresponds to the constraint that quantum theory cannot be used for a superluminal communication. Finally, a general bound to the guessing probability is presented in a closed form. © 2011 American Physical Society.
Oh D.Y.,University of California at San Diego |
Morinaga H.,University of California at San Diego |
Talukdar S.,University of California at San Diego |
Bae E.J.,Woosuk University |
Olefsky J.M.,University of California at San Diego
Diabetes | Year: 2012
Macrophage-mediated inflammation is a key component of insulin resistance; however, the initial events of monocyte migration to become tissue macrophages remain poorly understood. We report a new method to quantitate in vivo macrophage tracking (i.e., blood monocytes from donor mice) labeled ex vivo with fluorescent PKH26 dye and injected into recipient mice. Labeled monocytes appear as adipose, liver, and splenic macrophages, peaking in 1-2 days. When CCR2 KO monocytes are injected into wild-type (WT) recipients, or WT monocytes given to MCP-1 KO recipients, adipose tissue macrophage (ATM) accumulation is reduced by ∼40%, whereas hepatic macrophage content is decreased by ∼80%. Using WT donor cells, ATM accumulation is several-fold greater in obese recipient mice compared with lean mice, regardless of the source of donor monocytes. After their appearance in adipose tissue, ATMs progressively polarize from the M2- to the M1-like state in obesity. In summary, the CCR2/MCP-1 system is a contributory factor to monocyte migration into adipose tissue and is the dominant signal controlling the appearance of recruited macrophages in the liver. Monocytes from obese mice are not programmed to become inflammatory ATMs but rather the increased proinflammatory ATM accumulation in obesity is in response to tissue signals. © 2012 by the American Diabetes Association.
Goo J.,Woosuk University
Fire Safety Journal | Year: 2012
Smoke affects fire detection and visibility as well as the number of fire victims through inhalation. The size distributions of smoke particles are prerequisites for understanding the characteristics of fire smoke. The purpose of this work is to find the characteristics for the development of the size distribution of smoke particles in a compartment fire. In this work, the dynamic equation for the discrete-size spectrum of particles was solved using the nodal method. The collision frequency function for the entire regime, reflecting the fractal dimension of the particles, was applied. The results were presented for each variation of the parameters such as the history of the heat release rate, smoke yield, and the size of primary particles. © 2011 Elsevier Ltd. All rights reserved.
Hwang J.K.,Woosuk University
IEEE Transactions on Power Delivery | Year: 2014
An electric power system is monitored and controlled on the basis of its phasor information, such as amplitude, phase angle, and frequency. This phasor can be measured through discrete Fourier transform (DFT) coefficients of its positive nominal frequency. Then, the frequency estimate can be calculated from time variation of the measured phasor angle. The accuracy of the phasor-angle measurement and the frequency estimation are severely affected by noise in the power system signal and the leakage of the negative fundamental frequency in DFT. This paper proposes a DFT-based phasor-angle measurement algorithm to cope with both the noise effect and the leakage effect. In addition, a frequency estimation algorithm is developed to use the same technique in the phasor-angle measurement algorithm. These algorithms introduce two digital filters for the reduction of the noise effect. The effectiveness of the proposed algorithm in the noise effect reduction is verified through simulations. © 1986-2012 IEEE.
Kwon M.H.,Woosuk University
Transactions on Electrical and Electronic Materials | Year: 2012
I studied the stability of organic photovoltaic cells in terms of P3HT:PCBM-71 blend ratio as a function of storage time. I obtained the best cell performance by optimizing the blend ratio of electron donor and electron acceptor within the active layer. In this study, I found that the more the P3HT:PCBM ratio increases within the active layer, the more the cell efficiency decreases as the storage time increases. As a result, the best optimized blend ratio was the 1:0.6 ratio of P3HT:PCBM-71, and cell efficiency of the device with the 1:0.6 blend ratio was 4.49%. The device with the best cell efficiency showed good stability. © 2012 KIEEME. All rights reserved.
Ruby Co. and Woosuk University | Date: 2013-09-13
The present invention relates to a golf navigation terminal and a golf navigation device using the same. One of the things people always care about when playing golf is scorekeeping. The present invention automatically calculates a score so that a golf player can concentrate on his or her play. When the golf player plays a game, while wearing the golf navigation terminal of the present invention on the waist, the golf navigation terminal automatically detects how the player is doing and sends this to the golf navigation device, and the golf navigation device then calculates the players score. Afterwards, the score is wirelessly communicated to the golf navigation terminal. The score is fixed after the players confirmation or correction. According to the present invention, the player may view his or her score from time to time, either through a display on the golf navigation terminal or on the golf navigation device.