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Chiba, Japan

Chiba University and it is also abbreviated as Chibadai is a national university in the city of Chiba, Japan. It offers Doctoral degrees in education as part of a coalition with Tokyo Gakugei University, Saitama University, and Yokohama National University. The university was formed in 1949 from existing educational institutions in Chiba Prefecture, and absorbed over a period of years Chiba Medical University , a preparatory department of the Tokyo Medical and Dental University, Chiba Normal School , Tokyo Polytechnic High School , Chiba Horticultural High School, and others. Chiba University was reincorporated in 2010 under the National University Corporation Act. Chiba University has been ranked 75th on the Asia University Rankings 2013 Top 100 by "The Times Higher Education".Currently, Chiba University consists of nine faculties, the university library, the university hospital and other educational and research facilities. With 11,179 students in the undergraduate program, it has long been one of the largest universities in Japan. As for the graduate school, there are about 2,354 students in ten master's programs and 1,220 in nine doctoral programs.Chiba University is proud of its productive faculties and varied courses, the particulars of which will be introduced in the following sections. The University's four campuses, Nishi-Chiba, Inohana, Matsudo, and Kashiwanoha are ideally located in Chiba Prefecture, an area noted for its industrial, intellectual and international achievements. In recent decades Chiba has undergone rapid development which in many ways rivals the neighboring Tokyo Metropolis. Many national projects have been based in Chiba Prefecture, and now Chiba has one of the main international transport centers and one of the largest business centers in Japan . Many new academic and industrial complexes for the advanced science are located in Chiba Prefecture. The developments in Chiba today are representative of tomorrow's Japan. Matters occurring in the most progressive parts of Japan, or even in the world, will provide rich materials for research in various aspects of the human, social, industrial and natural science.Chiba University has achieved a high degree of participation in international cooperative research projects. Chiba University presently has a large body of international research scholars and students studying on its various campuses. As of 2009, there are approximately 477 international researcher and 957 international students. Starting October, 1996, Chiba University launched a one-year scholarship program designed to provide international students with the opportunity to take courses in English. Wikipedia.

Ohba T.,Chiba University
Journal of Physical Chemistry C | Year: 2015

Knowledge of the dynamic properties of electrolyte solutions during charge and discharge cycles is crucial for understanding and developing electric energy devices. Molecular dynamics simulations of aqueous NaCl solution in nanopores between charged graphene layers were performed to assess the dynamical mechanism of ion transfer. Ions moved to the oppositely charged graphene layer according to the strength of their partial charges. The ion hydration numbers increased during ion transfer, suggesting quick rearrangement of water molecules around the ions to form a hydration shell. The extent of hydrogen bonding also increased during ion transfer. Water molecules participating in ion transfer hydrated the ion and simultaneously maintained hydrogen bonding, supporting a quick ion transfer mechanism during charge and discharge cycles. © 2015 American Chemical Society. Source

Ando Y.,Pharmaceuticals and Medical Devices Agency | Uyama Y.,Office of Regulatory Science Pharmaceuticals and Medical Devices Agency | Uyama Y.,Chiba University
Journal of Biopharmaceutical Statistics | Year: 2012

Multiregional clinical trials including Japanese subjects are playing a key role in new drug development in Japan. In addition to the consideration of differences in intrinsic and extrinsic ethnic factors, deciding the sample size of Japanese subjects is an important issue when a multiregional clinical trial is intended to be used for Japanese submission. Accumulated experience suggests that there are several points to consider, such as the basic principles described in the guidance document, drug development strategy, trial phase, and disease background. The difficulty of interpreting the results of Japanese trials should also be considered. © 2012 Taylor and Francis Group, LLC. Source

Yonezawa N.,Chiba University
Advances in Experimental Medicine and Biology | Year: 2014

The zona pellucida (ZP), which surrounds the mammalian oocyte, functions in various aspects of fertilization. The ZP consists of three or four glycoproteins, which are derived from transmembrane proteins that lack the ability to selfassemble. Following posttranslational processing at specific sites, ectodomains of ZP precursor proteins are released from the membrane and begin to form a matrix. Glycosylational modification is thought to be involved in speciesselective sperm recognition by ZP proteins. However, in mice, the supramolecular structure of the zona matrix is also important in sperm recognition. One ZP protein, ZP2, is processed at a specific site upon fertilization by ovastacin, which is released from cortical granules inside the oocyte. This phenomenon is involved in the block to polyspermy. The proteolysis of ubiquitinated ZP proteins by a sperm-associated proteasome is involved in penetration of the zona matrix by sperm, at least in the pigs. Thus, the posttranslational modification of ZP proteins is closely tied to ZP formation and the regulation of sperm–oocyte interactions. © Springer Science+Business Media New York 2014. Source

Kitagawa M.,Chiba University
Journal of Biochemistry | Year: 2015

Notch signalling plays pivotal roles in development and homeostasis of all metazoan species. Notch is a receptor molecule that directly translates information of cell-cell contact to gene expression in the nucleus. Mastermind is a conserved and essential nuclear factor that supports the activity of Notch. Here, the past and current studies of the interplay between these factors are reviewed. © 2015 The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved. Source

Sawayama M.,Nippon Telegraph and Telephone | Kimura E.,Chiba University
Vision Research | Year: 2015

When distinguishing illumination from reflectance edges, both edge blurriness and textural continuity across an edge are generally used as cues to promote the illumination-edge interpretation. However, when these cues were combined, i.e., when a dark spot having a blurred edge was placed on textured backgrounds, we unexpectedly found that the spot appears stained or painted rather than differently illuminated ("stain on texture" phenomenon). This phenomenon suggests a disruptive interaction between the visual processing of blurred edges and background texture. Our experiments showed that middle spatial-frequency components of background texture play a critical role in producing this interaction. Specifically, when a textured background had relatively stronger energy in middle spatial-frequency bands, the dark spot having a blurred edge on the textured background was perceived as differing in reflectance. The findings are discussed in view of multiple levels of visual processes: one mainly concerns low-level features such as spatial-frequency components and another is a higher-level process that takes into account the likelihood of spatial configurations in natural scenes, such as "spot shadow" in which the shadow is isolated and the shadow caster is out of sight. © 2014 The Authors. Source

Nishihara S.,A+ Network | Hajduczenia M.,University of Coimbra | Mukai H.,Chiba University | Elbakoury H.,University of Waterloo | And 2 more authors.
IEEE Communications Magazine | Year: 2012

Given the growing need for high-speed access networks with reliable service delivery and lifeline support, fiber-based access rapidly becomes the prevailing solution around the world. Ethernet passive optical network addresses the environmental impact of fiber access through advanced power-saving mechanisms, which reduce the power consumption of customer equipment while preserving customer experience. © 2012 IEEE. Source

Young R.S.L.,Texas Tech University Health Sciences Center | Kimura E.,Chiba University
Documenta Ophthalmologica | Year: 2010

The aim of the study was to describe a theory and method for inferring the statistical significance of a visually evoked cortical potential (VEP) recording. The statistical evaluation is predicated on the pre-stimulus VEP as estimates of the cortical potentials expected when the stimulus does not produce an effect, a mathematical transform to convert the voltages into standard deviations from zero, and a time-series approach for estimating the variability of between-session VEPs under the null hypothesis. Empirical and Monte Carlo analyses address issues concerned with testability, statistical validity, clinical feasibility, as well as limitations of the proposed method. We conclude that visual electrophysiological recordings can be evaluated as a statistical study of n = 1 subject using time-series analysis when confounding effects are adequately controlled. The statistical test can be performed on either a single VEP or the difference between pairs of VEPs. Source

This study draws on video recordings of 12 massage therapy sessions that took place in Japan. During massage therapy sessions, therapists produce utterances regarding massaging procedures. This study investigates the ways such procedural utterances are syntactically constructed in different sequential contexts and bodily configurations. The procedural utterances take three forms: the request form, the proposal form, and the announcement form. Two observations have been made. First, various movements, including the movements that are mentioned in the procedural utterances, are initiated during the utterances. Second, the placement of the different syntactic forms of procedural utterances varies relative to the stage of the ongoing therapy session and the concurrent body movement. I argue that procedural utterances are constructed normatively sensitively to the tactile orientations that accompany bodily manipulations and that this normative sensitivity can be a resource for the negotiation between the therapist and the client regarding the incipient procedure. © 2016 Elsevier B.V. Source

Werner P.,University of Fribourg | Werner P.,ETH Zurich | Casula M.,University Pierre and Marie Curie | Miyake T.,Japan National Institute of Advanced Industrial Science and Technology | And 6 more authors.
Nature Physics | Year: 2012

Superconductivity has recently been discovered in several families of iron-based compounds, but despite intense research even such basic electronic properties of these materials as Fermi surfaces, effective electron masses and orbital characters are still subject to debate. Here, we address an issue that has not been considered before, namely the consequences of dynamical screening of the Coulomb interactions between Fe d electrons. We demonstrate that dynamical screening effects are important not only for higher-energy spectral features, such as correlation satellites seen in photoemission spectroscopy, but also for the low-energy electronic structure. Our analysis indicates that BaFe 2As 2 is a strongly correlated compound with strongly doping- and temperature-dependent properties. In the hole-overdoped regime an incoherent metal is found, whereas Fermi-liquid behaviour is recovered in the undoped compound. At optimal doping, the self-energy exhibits an unusual square-root energy dependence, which leads to strong band renormalizations near the Fermi level. © 2012 Macmillan Publishers Limited. All rights reserved. Source

BACKGROUND/PURPOSE:: To determine the relationship between the alterations in the preoperative morphology of the retinal pigment epithelium (RPE) and the postoperative recovery after surgery to close an idiopathic macular hole (MH). METHODS:: Retrospective interventional case series. Fifty-nine eyes of 59 patients with an idiopathic MH were studied. Pars plana vitrectomy was performed with the removal of the internal limiting membrane. The best-corrected visual acuity was measured, and the retinal morphology, including the presence of small RPE protrusions at the bottom of MH, was determined by spectral domain optical coherence tomography before and at 1, 3, and 6 months postoperatively. RESULTS:: The mean age of the patients was 66.7 years. Forty eyes (68%) had preoperative alterations of the RPE. The minimal (P < 0.001) and the base (P < 0.001) diameters of the MH were significantly larger in eyes with preoperative RPE alterations. The best-corrected visual acuity was significantly worse at baseline (P = 0.014) and at 6 months postoperatively (P = 0.048) in the eyes with RPE alterations. The defect of the ellipsoid zone was significantly longer in eyes with baseline RPE alterations at 1, 3, and 6 months postoperatively (P < 0.001, P = 0.001, and P = 0.032). CONCLUSION:: The presence of RPE protrusions at baseline was significantly correlated with slower morphologic recovery and poorer visual acuity after MH closure. © 2016 by Ophthalmic Communications Society, Inc. Source

PURPOSE:: We investigated whether scleral imbrication combined with pars plana vitrectomy without internal limiting membrane peeling would be effective in treating eyes with myopic macular schisis. METHODS:: In this retrospective, interventional case series, 8 eyes of 8 patients with myopic retinoschisis without a macular hole were studied. Scleral imbrication was done with 6-mm-wide mattress sutures placed at the temporal quadrants. Pars plana vitrectomy and removal of the vitreous cortex were performed, but the internal limiting membrane was not removed. The best-corrected visual acuity was measured, and the retinal morphology was determined by spectral-domain optical coherence tomography before and at 6 and 12 months postoperatively. RESULTS:: The mean age of the subjects was 67.1 years. The best-corrected visual acuity improved from 0.71 ± 0.25 to 0.36 ± 0.19 logarithm of the minimum angle of resolution units (Snellen equivalent: from 20/100 to 20/50) at 12 months (P = 0.028). The axial length was shortened from 29.5 ± 1.7 to 28.5 ± 2.5 at 12 months (P = 0.012). The central foveal thickness decreased from 540 ± 171 μm to 170 ± 85 μm at 12 months (P = 0.012). In the 6 macular-detached eyes, 5 eyes (83%) had a complete resolution. The curvature of posterior eye wall was flatter at 12 months (P = 0.049). No retinal complications were observed. CONCLUSION:: Scleral imbrication combined with pars plana vitrectomy can be an effective method of treating myopic schisis. © 2016 by Ophthalmic Communications Society, Inc. Source

Hashimoto K.,Chiba University
Nihon Arukōru Yakubutsu Igakkai zasshi = Japanese journal of alcohol studies & drug dependence | Year: 2013

Accumulating evidence suggests a role of inflammation in the pathophysiology of a number of neuropsychiatric diseases. The second generation antibiotic drug minocycline has potent neuroprotective and anti-inflammatory effects. We reported that minocycline could attenuate behavioral abnormalities and dopaminergic neurotoxicity in mice after administration of methamphetamine or 3,4-methylenedioxymethamphetamine (MDMA). Furthermore, we reported that minocycline was effective in the animal models of schizophrenia. Moreover, a double-blind, placebo-control, cross-over study showed that minocycline was effective in the rewarding effects in healthy human subjects. In this article, we would like to discuss minocycline as a potential therapeutic drug for methamphetamine-related disorders. Source

It is essential to perform electromyography and nerve-conduction studies for diagnosis amyotrophic lateral sclerosis (ALS), but these conventional electrophysiologic methods cannot be used for studies on the mechanism underlying ALS. The recently developed nerve-excitability test can provide new insights into the pathophysiology of this disease. Fasciculation is one of the characteristic features of ALS. Ectopic firing of motor units originates usually from the motor nerve terminals and occasionally from the motor neurons, indicating a widespread abnormality in axonal excitability. ALS is a multifactorial disease in which some genetic abnormalities and environmental factors lead to cell death through a complex cascade, which includes oxidative stress, mitochondrial dysfunction, excitotoxicity, and impaired axonal transport. It is important to elucidate the pathophysiology of axonal excitability in ALS because increased axonal excitability enhances oxidative stress and excitotoxicity, ultimately contributing to motor neuron death. To date, 2 axonal ion channel abnormalities have been identified: (1) increased persistent sodium currents and (2) reduced potassium currents; both abnormalities cause an increase in axonal excitability and are responsible for fasciculations. The results for excitability testing in such patients are characterized by the following features: (1) a prolonged strength-duration time constant, which suggests increased persistent sodium currents; (2) greater threshold changes in depolarizing threshold electrotonus; and (3) greater supernormality, which suggests impaired potassium channels. The altered axonal properties in patients with ALS may provide new insights into the pathophysiology of ALS and have implications for the development of ion channel modulators as therapeutic options for patients with ALS. Source

Nakai S.,Hiroshima University | Okuda T.,Hiroshima University | Okada M.,Chiba University
Chemosphere | Year: 2015

Ozonation is believed to improve the biodegradability of organic compounds. In the present study, degradation of nonylphenol ethoxylates (NPEOs) was monitored in hybrid treatment systems consisting of ozonation and microbial degradation processes. We found that ozonation of NPEOs decreased, rather than increased, the biodegradability under certain conditions. The timing of ozonation was a definitive factor in determining whether ozonation increased or decreased the biodegradation rates of NPEOs. Initial ozonation of NPEOs prior to biodegradation reduced the rate of dissolved organic carbon (DOC) removal during the subsequent 14d of biodegradation, whereas intermediate ozonation at the 9th day of biodegradation improved subsequent DOC removal during 14d of NPEO biodegradation. Furthermore, reduction of DOC removal was also observed, when initial ozonation prior to biodegradation was subjected to cetyl alcohol ethoxylates. The production of less biodegradable intermediates, such as mono- and dicarboxylated polyethylene glycols (MCPEGs and DCPEGs), was responsible for the negative effect of ozonation on biodegradability of NPEOs. DCPEGs and MCPEGs were produced by biodegradation of polyethylene glycols (PEGs) that were ozonolysis products of the NPEOs, and the biodegradability of DCPEGs and MCPEGs was less than that of the precursor PEGs. The results indicate that, if the target chemicals contain ethoxy chains, production of PEGs may be one of the important factors when ozonation is considered. © 2015 Elsevier Ltd. Source

Franchetti Y.,Dana-Farber Cancer Institute | Franchetti Y.,Harvard University | Ide H.,Chiba University
BMC Public Health | Year: 2014

Background: It is unknown whether childhood physical development in Asian populations differs from western populations, since no longitudinal analysis has been performed in Asian countries yet. Utilizing the 21st Century Longitudinal Survey in Newborns, we studied the timing of adiposity rebound (AR) among Japanese children and determined whether AR occurs earlier in obese children compared to nonobese children. Furthermore, we identified important demographic, social, and lifestyle factors that affect their physical development. Methods. We used data from the annual surveillance of Japanese children born in 2001, with 45,392 eligible subjects. We applied survival analysis to evaluate the AR and a trajectory method for the BMI transition across 5years. Time-dependent and time-independent factors affecting BMI changes were investigated using longitudinal analysis. Accounting for the known difference in prevalence between Japanese and Western children, we adopted a 95th percentile of BMI as criterion for obesity. Results: Mean BMI at birth and at ages 1 , 2 , 3 , 4 , and 5years for all subjects were 12.6, 16.3, 16.1, 15.8, 15.5, and 15.4, respectively, showing a progressive reduction after 1years. However, among obese children at 5years, 39.6% had experienced AR as early as at age 4years. Controlling for sex, Cox's proportional hazards model showed that obese children had a 48.5% higher hazard to experience AR than nonobese children. The difference in BMI transition between obese and non-obese children was also captured by a trajectory method. In longitudinal analysis, BMI was lower for children who had a longer gestational period whereas children who received parental care from non-family members gained higher BMI values. Conclusions: With the 95th percentile cutoff for children obesity, obese Japanese children developed AR earlier than nonobese Japanese children, similar to those in Western countries reported in the literature. Primary caretakers and length of gestational period were the most important socio-demographic factors affecting physical development. © 2014 Franchetti and Ide; licensee BioMed Central Ltd. Source

Kondo K.-I.,Chiba University | Shibata A.,High Energy Accelerator Research Organization
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2015

In the SU(2) Yang-Mills theory on the four-dimensional Euclidean lattice, we confirm the gauge-independent "Abelian" dominance (or the restricted field dominance) and gauge-independent magnetic-monopole dominance in the string tension of the linear potential extracted from the Wilson loop in the fundamental representation. The dual Meissner effect is observed by demonstrating the squeezing of the chromoelectric field flux connecting a pair of a quark and an antiquark. In addition, the circular magnetic-monopole current is induced around the chromoelectric flux. The type of the dual superconductivity is also determined by fitting the result with the dual Ginzburg-Landau model. Thus, the dual superconductor picture for quark confinement is supported in a gauge-independent manner. These results are obtained based on a reformulation of the lattice Yang-Mills theory based on the change of variables à la Cho-Duan-Ge-Faddeev-Niemi combined with a non-Abelian Stokes theorem for the Wilson loop operator. We give a new procedure (called the reduction) for obtaining the color direction field that plays the central role in this reformulation. © 2015 American Physical Society. Source

Hoshino I.,Chiba University
Surgery today | Year: 2013

Epigenetic changes, such as DNA methylation and histone modifications, regulate gene expression. It is speculated that investigating the fundamental epigenetic mechanisms and their gene regulation will promote a better understanding of cancer development. The idea of epigenetic modification has been extended to microRNAs (miRs). MiRs are single-stranded RNA molecules, about 19-25 ribonucleotides in length, which regulate gene expression post-transcriptionally and can act as tumor suppressors or oncogenes. We review the most recent findings related to their mechanisms of action, the modification of miR expression, and their relationship to cancer. We also discuss the potential application of miRs in the clinical setting, such as for biomarkers and therapy. Source

Vargas M.A.,Buck Institute for Age Research | Luo N.,Buck Institute for Age Research | Yamaguchi A.,Chiba University | Kapahi P.,Buck Institute for Age Research
Current Biology | Year: 2010

Balancing intake of diverse nutrients is important for organismal growth, reproduction, and survival. A shift in an organism's optimal diet due to changes in nutritional requirements after developmental or environmental changes is referred to as dietary switch and has been observed in several species [1]. Here we demonstrate that female Drosophila melanogaster also undergo a dietary switch following mating that leads to an increased preference for yeast, the major source of protein in their diet. We also demonstrate that S6 kinase (S6K) and serotonin production are involved in the postmating dietary switch. To further investigate the ability of D. melanogaster to balance nutrient intake, we examined the dietary preferences of adult flies following deprivation of yeast or sucrose. We observe that following conditioning on a diet deficient in either carbohydrates or yeast, D. melanogaster show a strong preference for the deficient nutrient. Furthermore, flies with activated dS6K or flies fed a serotonin precursor exhibit enhanced preference for yeast in this assay. Our results suggest that TOR signaling and serotonin may play an important role in maintaining nutrient balance in D. melanogaster. These studies may contribute to our understanding of metabolic disorders such as obesity and diabetes [2]. © 2010 Elsevier Ltd. All rights reserved. Source

Sasamoto T.,Chiba University | Spohn H.,TU Munich
Journal of Statistical Physics | Year: 2010

We consider the asymmetric simple exclusion process in one dimension with weak asymmetry (WASEP) and 0-1 step initial condition. Our interest are the fluctuations of the time-integrated particle current at some prescribed spatial location. One expects a crossover from Gaussian to Tracy-Widom distributed fluctuations. The appropriate crossover scale is an asymmetry of order √ε, times of order ε-2, and a spatial location of order ε-3/2. For this parameter window we obtain the limiting distribution function of the integrated current in terms of an integral over the difference of two Fredholm determinants. For large times, on the scale ε-2, this distribution function converges to the one of Tracy-Widom. © 2010 Springer Science+Business Media, LLC. Source

Sasamoto T.,Chiba University | Spohn H.,TU Munich
Journal of Statistical Mechanics: Theory and Experiment | Year: 2010

We explain the exact solution of the 1 + 1-dimensional Kardar-Parisi-Zhang equation with sharp wedge initial conditions. Thereby it is confirmed that the continuum model belongs to the KPZ universality class, not only as regards scaling exponents but also as regards the full probability distribution of the height in the long time limit. © 2010 IOP Publishing Ltd and SISSA. Source

Fausch K.D.,Colorado State University | Baxter C.V.,Idaho State University | Murakami M.,Hokkaido University | Murakami M.,Chiba University
Freshwater Biology | Year: 2010

Streams are highly connected to their landscapes and so are easily altered by multiple stressors that affect both uplands and riparian zones, and the streams themselves. These include dams and diversions, channelisation, deforestation, water pollution, biological invasions and climate change. 2. We review research conducted in Hokkaido Island, northern Japan, which measured the effects of many of these stressors on both stream food webs and fluxes of invertebrates to and from the riparian zone that feed aquatic and terrestrial consumers. About half the energy that sustains fish falls directly into streams as terrestrial invertebrates, and a quarter of the energy needs for riparian birds is supplied by adult aquatic insects emerging from the stream. 3. Single stressors in these Hokkaido streams, including deforestation, channelisation, erosion-control dams, biological invasions and climate change, have drastic effects on stream food webs, the fishes they support and riparian predators (spiders, birds, and bats). Most stressors caused 30-90% declines in foraging, growth, or abundance of aquatic or terrestrial predators. Indirect effects of stressors also cascaded throughout stream food webs and across the aquatic-terrestrial boundary. 4. Effects of individual stressors were largely concordant across spatial scale, through time during years of different productivity and among different food web components. 5. Two studies of multiple stressors revealed that each stressor alone reduced food web components like abundance of stream benthos or riparian spiders to low levels (35-83% reduction; mean 59%), beyond which an additional stressor had little effect. Synergism and antagonism are less relevant when individual stressors have such large effects. 6. Thematic implications: small streams in Hokkaido are highly sensitive to many individual stressors and have little resistance or resilience to their effects. Moreover, each stressor alone can reduce biota strongly, indicating that restoration will need to consider all simultaneously to protect biotic diversity. © 2010 Blackwell Publishing Ltd. Source

Matui H.,Chiba University
Communications in Mathematical Physics | Year: 2010

We consider ℤ-actions (single automorphisms) on a unital simple AH algebra with real rank zero and slow dimension growth and show that the uniform outerness implies the Rohlin property under some technical assumptions. Moreover, two ℤ-actions with the Rohlin property on such a C*-algebra are shown to be cocycle conjugate if they are asymptotically unitarily equivalent. We also prove that locally approximately inner and uniformly outer ℤ2actions on a unital simple AF algebra with a unique trace have the Rohlin property and classify them up to cocycle conjugacy employing the OrderExt group as classification invariants. © 2009 Springer-Verlag. Source

Tabata M.,Sakakibara Heart Institute | Shibayama K.,Sakakibara Heart Institute | Watanabe H.,Sakakibara Heart Institute | Sato Y.,Chiba University | And 2 more authors.
Journal of Thoracic and Cardiovascular Surgery | Year: 2014

Objective: A supra-annular aortic valve prosthesis is often used for aortic valve replacement in patients with a small aortic annulus. However, which suture technique provides the best valve performance has not been studied. We aimed to compare valve performance between 2 different suture techniques. Methods: We reviewed 152 patients undergoing aortic valve replacement with a 19- or 21-mm Carpentier-Edwards Perimount Magna aortic bioprosthesis (Edwards Lifesciences, Irvine, Calif) between June 2008 and December 2010. Simple interrupted sutures were used in 102 patients (group A, 19-mm prosthesis in 47 patients and 21-mm prosthesis in 55 patients), and noneverting mattress sutures were used in 50 patients (group B, 19-mm prosthesis in 20 patients and 21-mm prosthesis in 30 patients). Transthoracic echocardiograms were performed at baseline and before discharge in all patients and 1 year after surgery in 141 patients. We compared the effective orifice area and incidence of prosthesis-patient mismatch (effective orifice area index <0.85 cm 2/m2) between 2 groups. Results: The mean postoperative effective orifice areas were 1.41 ± 0.32 cm2/m2 in group A and 1.30 ± 0.28 cm2/m2 in group B (P =.025). The incidence of prosthesis-patient mismatch was 29% in group A and 56% in group B (P =.002). A multivariate analysis has shown that simple interrupted suturing is a negative predictor of prosthesis-patient mismatch (odds ratio, 0.33; 95% confidence interval, 0.13-0.83; P =.018). At 1 year, the incidence of prosthesis-patient mismatch was 27% in group A and 47% in group B (P =.023). Conclusions: Simple interrupted sutures provide larger effective orifice areas and reduce the incidence of prosthesis-patient mismatch after aortic valve replacement with a small supra-annular bioprosthesis. This suture technique is preferred in those patients to maximize valve performance. Copyright © 2014 by The American Association for Thoracic Surgery. Source

Takotsubo cardiomyopathy (TTC) is characterized by transient left ventricular apical ballooning with the absence of coronary occlusion, which typically occurs in older women after emotional or physical stress. The pathophysiology of TTC is not well established, though several possible causes such as catecholamine cardiotoxicity, metabolic disturbance, coronary microvascular impairment and multivessel epicardial coronary artery spasm have been proposed. A number of diagnostic criteria have been suggested in the world and not unified as single, but the most common accepted one is Mayo Clinic proposed criteria. Since the clinical presentation of TTC is usually similar to acute coronary syndrome, differential diagnosis is essential to exclude other diseases and also for its treatment. Imaging modality including echocardiogram, angio CT and cardiac MRI, and lab tests for catecholamine, troponin T, creatine kinase MB and B-type natriuretic peptide can be useful to differentiate TTC from other diseases. Prognosis is generally favorable and in-hospital mortality is from 0% to within 10%. © 2016 Elsevier Ireland Ltd. All rights reserved. Source

Fujikawa E.,Chiba University
Computational Methods and Function Theory | Year: 2014

We consider the infinite dimensional Teichmüller space of a Riemann surface of general type. On the basis of the fact that the action of the quasiconformal mapping class group on the Teichmüller space is not discontinuous, in general, we divide the Teichmüller space into two disjoint subsets, the limit set and the region of discontinuity, according to the discreteness of the orbit by a subgroup of the quasiconformal mapping class group. The asymptotic Teichmüller space is a certain quotient space of the Teichmüller space and there is a natural projection from the Teichmüller space to the asymptotic Teichmüller space. We consider the fibers of the projection over any point in the asymptotic Teichmüller space, and show a coherence of the discreteness on each fiber in the Teichmüller space. © 2014, Springer-Verlag Berlin Heidelberg. Source

Hamad A.M.,Menoufia University | Tsumura N.,Chiba University
Optical Review | Year: 2012

This paper proposes a robust method to detect and extract silhouettes of foreground objects from a video sequence of a static camera based on the improved background subtraction technique. The proposed method analyses statistically the pixel history as time series observations. The proposed method presents a robust technique to detect motions based on kernel density estimation. Two consecutive stages of the k-means clustering algorithm are utilized to identify the most reliable background regions and decrease the detection of false positives. Pixel and object based updating mechanism for the background model is presented to cope with challenges like gradual and sudden illumination changes, ghost appearance, non-stationary background objects, and moving objects that remain stable for more than the half of the training period. Experimental results show the efficiency and the robustness of the proposed method to detect and extract the silhouettes of moving objects in outdoor and indoor environments compared with conventional methods. © 2012 The Optical Society of Japan. Source

Nara Y.,Chiba University
International Journal of Advanced Intelligence Paradigms | Year: 2010

This paper aims to examine the status quo of people's perception or coping with earthquakes, and the effects of risk experience and risk information to promote risk management in China. Questionnaire surveys were carried out before and after the Sichuan earthquake in China, and the same surveys were also conducted in Japan and the USA. The survey results clarified that the respondents in China showed lower levels of anxiety and higher self-evaluation of risk coping than did the Japanese respondents. The effect of risk experience was observed as the awareness and counter-measures with respect to earthquakes improved, especially among Chengdu's residents after the Sichuan earthquake. Significant effect from obtaining information on actual risk management action was also observed. Copyright © 2010 Inderscience Enterprises Ltd. Source

Nagase A.,Chiba University | Dunnett N.,University of Sheffield
Landscape and Urban Planning | Year: 2012

Increased stormwater runoff from impervious surfaces is a major concern in urban areas and green roofs are increasingly used as an innovative means of stormwater management. However, there are very few studies on how different vegetation types affect the amount of water runoff. This paper describes an experiment that investigates the influence of plant species and plant diversity on the amount of water runoff from a simulated green roof. Twelve species were selected from the three major taxonomic and functional plant groups that are commonly used for extensive green roofs (forbs, sedum and grasses). Four species were chosen from each group and planted in combinations of increasing diversity and complexity: monocultures, four-species mixtures and twelve-species mixtures. The results showed that there was a significant difference in amount of water runoff between vegetation types; grasses were the most effective for reducing water runoff, followed by forbs and sedum. It was also shown that the size and structure of plants significantly influenced the amount of water runoff. Plant species with taller height, larger diameter, and larger shoot and root biomass were more effective in reducing water runoff from simulated green roofs than plant species with shorter height, smaller diameter, and smaller shoot and root biomass. The amount of water runoff from Sedum spp. was higher than that from bare ground. Species richness did not affect the amount of water runoff in this study. © 2011 Elsevier B.V. Source

Kuwabara S.,Chiba University
Brain and Nerve | Year: 2011

The neuromuscular junction (NMJ) is a specialized synapse with a complex structural organization. Muscle contraction involves several steps: (1) nerve conduction to depolarize the motor nerve terminals, (2) opening of voltage-gated calcium channels (VGCCs) in the presynaptic membrane, (3) generation of endplate potential in the postsynaptic membrane via acetylcholine receptors, (4) depolarization of muscle sodium channels, and (5) excitation-contraction (E-C) coupling. Each step can be affected by various diseases. Guillain-Barre syndrome involves distal axons and possibly the presynaptic NMJ. The abnormalities can be detected by nerve conduction studies and single-fiber electromyography (SFEMG). Myasthenia gravis (MG) with anti-acetylcholine receptor (AChR) antibodies, is the most common NMJ disorder, and ∼5% of myasthenia patients are positive for anti-muscle specific kinase (MuSK) antibodies. Patterns and severity of neuromuscular transmission failure detected by repetitive nerve stimulation test and SFEMG are somewhat different in AChR-MG and MuSK-MG. Excitation-contraction (E-C) coupling can be affected by MG, possibly via antibodies against ryanodine receptors. The E-C coupling time can be assessed with an accelerometer. Lambert-Eaton myasthenic syndrome is caused by antibodies against presynaptic VGCCs. This review will focus on neurophysiological testing, including SFEMG, and measurements of E-C coupling time with an accelerometer. In addition to confirming or excluding the diagnosis, these techniques can provide new insights into the pathophysiology of a variety of neuromuscular disorders. Source

Shimojo N.,Chiba University
Clinical and Experimental Allergy Reviews | Year: 2012

In Japan, loratadine, fexofenadine, cetirizine and epinastine are currently approved for paediatric use. However, none of these drugs is officially approved for use in children aged under 2 years, and therefore older second-generation antihistamines such as ketotifen and oxatomide are sometimes prescribed for these patients. Because ketotifen and oxatomide have relatively strong sedative effects, one should be cautious when using these antihistamines in young children. In fact, there are reports describing the development of West syndrome, an intractable epilepsy, in 4-month-old infants taking these drugs. Recent clinical trials in Japanese children with allergic rhinitis have shown no serious adverse effects associated with several new second-generation antihistamines, supporting previous overseas reports. New second-generation antihistamines should be approved in the near future for young children in Japan. © 2012 Blackwell Publishing Ltd. Source

Furuse T.,Red Cross | Hashimoto K.,Chiba University
Annals of General Psychiatry | Year: 2010

Background: Delirium in older adults is a common and serious acute neuropsychiatric syndrome, with core features of inattention and global cognitive impairment. Although antipsychotic drugs are the medications most frequently used to treat this syndrome, these drugs are associated with a variety of adverse events, including sedation, extrapyramidal side effects, and cardiac arrhythmias.Methods: We report on two cases in which monotherapy of the selective serotonin reuptake inhibitor and sigma-1 receptor agonist fluvoxamine was effective in ameliorating the delirium of patients with Alzheimer's disease.Results: Delirium Rating Scale (DRS) scores in the two patients with Alzheimer's disease decreased after fluvoxamine monotherapy.Conclusion: Doctors should consider that fluvoxamine could be an alternative approach in treating delirium in patients with Alzheimer's disease because of the risk of extrapyramidal side effects by antipsychotic drugs. © 2010 Furuse and Hashimoto; licensee BioMed Central Ltd. Source

Inoue S.,Mitsubishi Group | Tsumura N.,Chiba University
6th European Conference on Colour in Graphics, Imaging, and Vision 2012, CGIV 2012 | Year: 2012

Glossiness is one of the important qualities for printing paper. Glossiness is a specular reflection phenomenon in aspect of optics. Therefore, there are various methods of evaluating specular reflection phenomenon. When a person is evaluating the glossiness of paper, it is quite popular to visually inspect the glossiness by the sharpness of the reflected light image. In this paper, it is shown that this visual inspection can be expressed by a transfer function of specular reflection image. First, we discuss the possible use of point spread function of specular reflection (SR-PSF). A technique for measuring SR-PSF of paper is proposed. The measurement principle is a collimator method. This method has been used for the PSF measurement of typical transmittance optical system. We have developed the apparatus to measure SR-PSF. The SR-PSFs were measured for paper samples. The experimental results showed that the measured SR-PSF works as a transfer function for specular reflection image. Second, we show that the apparatus used for measuring SR-PSF also works as a goniophotometer within a narrow solid angle. It is shown that the reflection angle calculated theoretically meets well with that experimentally obtained. That is, a distribution of reflection angle can be calculated using SR-PSF data. It is thought that the spreading of specular reflection observed on paper samples is caused by the distribution of surface normals. Our results showed that SR-PSF and gonio-reflectance distribution are one phenomenon expressed in two different physical concepts. Our future study will be focused on new reflection model for computer graphics. Source

Yoshino I.,Chiba University
Japanese Journal of Cancer and Chemotherapy | Year: 2014

Cancer chemotherapy-induced anemia (CIA) is observed in approximately 70% of patients treated with cytotoxic chemotherapy. The hemoglobin concentration in the peripheral blood is ≤ 10 g/dL in 40% of these patients, and ≤ 8 g/dL in 23% of these patients. Red blood cell transfusion is performed in 16% of these patients. Since erythropoiesis-stimulating agents (ESA) are not approved in Japan, blood transfusion is the only choice of treatment for CIA. In Northwestern countries, ESA have been utilized for the treatment of CIA for > 20 years. Recently, however, the use of ESA has become regulated towing to concerns about the potential life-shortening effects, although ESA are still the treatment of choice for CIA. In this paper, the characteristics of CIA in Japan and the underlying issues have been discussed. Source

Furuse T.,Red Cross | Hashimoto K.,Chiba University
Annals of General Psychiatry | Year: 2010

Background: Postoperative delirium is a topic of great importance in the geriatric surgical specialty. Although antipsychotic drugs are the medications most frequently used to treat this syndrome, these drugs are associated with a variety of adverse events, including sedation, extrapyramidal side effects, and cardiac arrhythmias. Drug treatment for postoperative delirium requires careful consideration of the balance between the effective management of symptoms and potential adverse effects.Methods: We report on a Japanese woman (an 86-year-old (open reduction and internal fixation of the right femoral neck fracture), and two Japanese men (an 86-year-old (abdominal aortic aneurysm stent grafting), and a 77-year-old (right upper lobectomy due to lung tumour)) in which the selective serotonin reuptake inhibitor and sigma-1 receptor agonist fluvoxamine was effective in ameliorating the postoperative delirium of these patients.Results: Delirium Rating Scale scores in these patients dramatically decreased after treatment with fluvoxamine.Conclusions: Doctors should consider fluvoxamine as an alternative approach to treating postoperative delirium in older patients in order to avoid the risk of side effects and increased mortality by antipsychotic drugs. © 2010 Furuse and Hashimoto; licensee BioMed Central Ltd. Source

This paper reviews the reasons why plant factories with artificial light are recently interested in society, requirements for sustainable plant factories, the opportunities and challenges involved in the development of the technology and industry, and types of the plants suitable for plant factories with artificial light. Sustainable plant factories need to be designed and operated for producing high quality plants and transplants with minimum use of resource and minimum emissions of CO2 and environmental pollutants. For this purpose, the concept of "closed system" has been proposed, which is a structure with minimum ventilation, covered with thermally insulated opaque walls, containing multi-tiers (or racks) with artificial light sources. Advantages of this system over the greenhouse include: 1) culture period is shortened by 40-50% with uniform growth and high quality produce, 2) annual production capacity per floor area is 100-fold, and 3) percent reductions in resource consumption are considerable. For example, percent reduction is 100% for pesticide and 95% for irrigation water. Electricity consumption for producing one tomato transplant from a seed is about 300-400 kJ and its cost in Japan is about 1 JPY (0.008 Euro or 1 US cent as of 2011), and is 25 JPY for producing one butter head lettuce from a seed. Methods of developing integrative environmental control and reducing electricity consumption are discussed based mainly on theoretical consideration. Effects of environmental factors on the growth and development are beyond the scope of this paper. Source

Tanaka K.,Tokyo Institute of Technology | Hanaoka M.,Chiba University
Frontiers in Plant Science | Year: 2012

The plastid signal was originally defined as a pathway that informs the nucleus of the chloroplast status and results in the modulation of expression of nuclear-encoded plastid protein genes. However, the transfer of chloroplast genes into the nuclear genome is a prerequisite in this scheme, although it should not have been established during the very early phase of chloroplast evolution. We recently demonstrated in a primitive red alga that the plastid-derived Mg-protoporphyrin IX activates nuclear DNA replication (NDR) through the stabilization of a G1 cyclin, which coordinates the timing of organelle and NDR. This mechanism apparently does not involve any transcriptional regulation in the nucleus, and could have been established prior to gene transfer events. However, a retrograde signal mediating light-responsive gene expression may have been established alongside gene transfer, because essential light sensing and regulatory systems were originally incorporated into plant cells by the photosynthetic endosymbiont. In this short article, we discuss the origins, early days and evolution of the plastid retrograde signal(s). © 2013 Tanaka and Hanaoka. Source

Hino T.,Japan Science and Technology Agency | Hino T.,Tottori University | Iwata S.,Japan Science and Technology Agency | Iwata S.,Kyoto University | And 3 more authors.
Current Opinion in Structural Biology | Year: 2013

Membrane proteins act as gateways to cells, and they are responsible for much of the communication between cells and their environments. Crystallography of membrane proteins is often limited by the difficulty of crystallization in detergent micelles. Co-crystallization with antibody fragments has been reported as a method to facilitate the crystallization of membrane proteins; however, it is widely known that the generation of mouse monoclonal antibodies that recognize the conformational epitopes of mammalian integral membrane proteins is typically difficult. Here, we present our protocols to generate functional mouse antibodies for the membrane protein crystallography, which have enabled us to solve crystal structures of mammalian receptors and transporters complexed with antibody fragments. © 2013 Elsevier Ltd. Source

Kanda T.,Chiba University
Hepatology International | Year: 2016

Progress in interferon-free treatment against hepatitis C virus (HCV) has remained a challenge in patients with decompensated cirrhosis due to a paucity of information on efficacy and safety profiles. This review illustrates that interferon-free treatment could result in greater than 85 % sustained virological response (SVR) rates in patients with HCV genotype 1 and decompensated cirrhosis. The combination of pangenotypic HCV NS5A inhibitor velpatasvir and HCV NS5B inhibitor sofosbuvir has demonstrated high SVR rates in patients with HCV genotypes 1, 2, 3, 4 or 6 and decompensated cirrhosis. Certain patients discontinued treatment due to adverse events, death or having liver transplantation. Taken together, interferon-free treatment could produce higher SVR rates in decompensated hepatic cirrhosis. However, as adverse events were occasionally observed, liver transplantation should always be considered as well. Further improvements in treatment are called for in patients with decompensated cirrhosis. © 2016 Asian Pacific Association for the Study of the Liver Source

Saito T.,Chiba University
Methods in Enzymology | Year: 2010

Electroporation combined with surgery is a quick and highly efficient method to transfect nucleic acids into various embryonic tissues in a spatiotemporally restricted manner. Forceps-type electrodes facilitate transfection by delivering electric pulses from outside of the embryo. Many electroporated embryos survive in the pregnant mouse, are born, and are reared. The developing central nervous system (CNS) is a good target for transfection, because there are many neural progenitors adjacent to the ventricle, into which nucleic acids are relatively easily injected. The expression of transfected genes persists in neurons for months. © 2010 Elsevier Inc. Source

Kobayashi T.,Chiba University
Nihon Kokyūki Gakkai zasshi = the journal of the Japanese Respiratory Society | Year: 2011

Although the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and Lambert-Eaton myasthenic syndrome (LEMS) are often individually accompanied by small-cell lung carcinoma, simultaneous occurrence of the 2 syndromes is rare. A 61-year-old man was admitted to our hospital because of fatigue and myasthenia in the extremities, and small-cell lung carcinoma with pulmonary metastasis was diagnosed, together with SIADH and LEMS. These syndromes markedly ameliorated following tumor shrinkage, with 4 cycles of chemotherapy consisting of carboplatin and etoposide. On progression of the tumor thereafter, neither syndrome recurred. A literature review disclosed that these syndromes frequently resolve with tumor shrinkage. Source

Hanawa T.,Chiba University | Tomisaka K.,Japan National Astronomical Observatory | Tomisaka K.,Graduate University for Advanced Studies
Astrophysical Journal | Year: 2015

We have constructed two types of analytical models for an isothermal filamentary cloud supported mainly by magnetic tension. The first one describes an isolated cloud while the second considers filamentary clouds spaced periodically. Both models assume that the filamentary clouds are highly flattened. The former is proved to be the asymptotic limit of the latter in which each filamentary cloud is much thinner than the distance to the neighboring filaments. We show that these models reproduce the main features of the 2D equilibrium model of Tomisaka for a filamentary cloud threaded by a perpendicular magnetic field. It is also shown that the critical mass to flux ratio is , where M, Φ and G denote the cloud mass, the total magnetic flux of the cloud, and the gravitational constant, respectively. This upper bound coincides with that for an axisymmetric cloud supported by poloidal magnetic fields. We apply the variational principle for studying the Jeans instability of the first model. Our model cloud is unstable against fragmentation as well as the filamentary clouds threaded by a longitudinal magnetic field. The fastest growing mode has a wavelength several times longer than the cloud diameter. The second model describes quasi-static evolution of a filamentary molecular cloud by ambipolar diffusion. © 2015. The American Astronomical Society. All rights reserved.. Source

Abe A.,Chiba University
Proceedings - IEEE 13th International Conference on Data Mining Workshops, ICDMW 2013 | Year: 2013

According to the wide development of the World Wide Web world, many peoples have tend to mention 'big data'' and tried to make use of the 'big data.' They usually mention 'big data'' as a key to the happy future. However, it will be a dream which will not be realized. In this paper, I review problems in big data. Then I propose a concept of curation to deal with such big and complex data. © 2013 IEEE. Source

Sogawa K.,Chiba University
Rinsho byori. The Japanese journal of clinical pathology | Year: 2013

In a clinical diagnostic microbiology laboratory, the current method of identifying bacterial isolates is based mainly on phenotypic characteristics, such as the growth pattern on different media, colony morphology, Gram stain, and various biochemical reactions. These techniques collectively allow high-level accuracy in identifying most bacterial isolates, but they are costly and time-consuming. In our clinical microbiology laboratory, we prospectively assessed the ability of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) to identify bacterial strains that were routinely isolated from clinical samples. Bacterial colonies obtained from a total of 468 strains of 92 bacterial species isolated at the Department of Clinical Laboratory at Chiba University were directly placed on target MALDI plates, followed by the addition of CHCA matrix solution. The plates were then subjected to MALDI-TOF MS measurement, and the microorganisms were identified by pattern matching by the libraries in the BioTyper 2.0 software. The identification rates at species and genus levels were 91.7% (429/468) and 97.0% (454/468), respectively. MALDI-TOF MS is a rapid, simple, and high-throughput proteomic technique for the identification of a variety of bacterial species. Since colony to colony differences and the effects of culture duration on the results are minimal, it can be implemented in a conventional laboratory setting. Although for some pathogens, the preanalytic processes should be refined and current database should be improved to obtain more accurate results, the MALDI-TOF MS-based method generally performs as well as the conventional methods and is a promising technology in clinical laboratories. Source

Snow and ice algae are cold tolerant algae growing on the surface of snow and ice, and they play an important role in the carbon cycles for glaciers and snowfields in the world. Seasonal and altitudinal variations in seven major taxa of algae (green algae and cyanobacteria) were investigated on the Gulkana glacier in Alaska at six different elevations from May to September in 2001. The snow algal communities and their biomasses changed over time and elevation. Snow algae were rarely observed on the glacier in May although air temperature had been above 0 ° C since the middle of the month and surface snow had melted. In June, algae appeared in the lower areas of the glacier, where the ablation ice surface was exposed. In August, the distribution of algae was extended to the upper parts of the glacier as the snow line was elevated. In September, the glacier surface was finally covered with new winter snow, which terminated algal growth in the season. Mean algal biomass of the study sites continuously increased and reached 6.3 × 10 μl m-2 in cell volume or 13 mg carbon m-2 in September. The algal community was dominated by Chlamydomonas nivalis on the snow surface, and by Ancylonema nordenskiöldii and Mesotaenium berggrenii on the ice surface throughout the melting season. Other algae were less abundant and appeared in only a limited area of the glacier. Results in this study suggest that algae on both snow and ice surfaces significantly contribute to the net production of organic carbon on the glacier and substantially affect surface albedo of the snow and ice during the melting season. © 2013 IOP Publishing Ltd. Source

Ohba T.,Chiba University
Journal of Physical Chemistry C | Year: 2016

The unique water transport properties in nanospaces are essential for control of various chemical reactions, biochemical activities, and electrochemical systems. Fast water transport has been observed in one-dimensional nanospaces. However, water transport via zero-dimensional nanospaces has not yet been observed. Zero-dimensional nanospaces were obtained by extremely small and thin gate (zero-dimensional gate) insertion on graphene walls of single-walled carbon nanohorns. The water transport properties were examined by water vapor loading and release via the zero-dimensional gates, and molecular dynamics simulation. Although relatively large gates provided considerable adsorption hysteresis by long-term equilibrium, water vapor loading and release via the extremely small gates showed consecutive water loading and release. The molecular dynamics simulation showed consecutive water transport via the gates, probably because of lower energy barriers to water transport in the vicinity of the gates. The zero-dimensional gates rejected water vapor transfer, but admitted condensed water for transfer. © 2016 American Chemical Society. Source

Furuse T.,Red Cross | Hashimoto K.,Chiba University
Annals of General Psychiatry | Year: 2010

Background: Delirium is a highly prevalent disorder among older patients in intensive care units (ICUs). Although antipsychotic drugs are the medications most frequently used to treat this syndrome, these drugs are associated with a variety of adverse events, including sedation, extrapyramidal side effects, and cardiac arrhythmias. Drug treatment for delirium requires careful consideration of the balance between the effective management of symptoms and potential adverse effects.Methods: We report on five Japanese men (an 84 year old (acute aortic dissociation: Stanford type A), a 55 year old (traumatic subarachnoid hemorrhage and brain contusion), a 76 year old (sepsis by pyelonephritis), an 85 year old (cerebral infarction), and an 86 year old (pulmonary emphysema and severe pneumonia)) in which the selective serotonin reuptake inhibitor and sigma-1 receptor agonist fluvoxamine was effective in ameliorating the delirium of the patients.Results: Delirium Rating Scale (DRS) scores in these five patients dramatically decreased after treatment with fluvoxamine.Conclusion: Doctors should consider fluvoxamine as an alternative approach to treating delirium in ICU patients in order to avoid the risk of side effects and increased mortality from antipsychotic drugs. © 2010 Furuse and Hashimoto; licensee BioMed Central Ltd. Source

Minamino T.,Chiba University | Minamino T.,Japan Science and Technology Agency
Circulation Journal | Year: 2010

Epidemiological studies have shown that age is the chief risk factor for lifestyle-related diseases such as cardiovascular disease and diabetes, but the molecular mechanisms that underlie the increase in the risk of such diseases conferred by aging remain unclear. Recently, genetic analyses using various animal models have identified molecules that are crucial for aging. These include components of the DNA repair system, the tumor suppressor pathway, the telomere maintenance system, the insulin/Akt pathway, and other metabolic pathways. Interestingly, most of the molecules that influence the phenotypic changes of aging also regulate cellular senescence, suggesting a causative link between cellular senescence and aging. This review examines the hypothesis that cellular senescence might contribute to lifestyle-related disease. Source

Gonzalez P.,Hospital General de Mostoles | Gonzalez F.A.,Paediatrics Service | Ueno K.,Chiba University
Current Pharmaceutical Biotechnology | Year: 2012

Ivermectin is a broad spectrum antiparasitic veterinary drug introduced in human medicine in 1987. It is considered the drug of choice in onchocerciasis and strongyloidiasis infections, and remains as a therapeutic option for mass treatment in lymphatic filariasis, for which it has widely proved its efficacy. While research continued for human use, new therapeutic targets for ivermectin have emerged. It is currently the better therapeutic option in the treatment of gnathostomiasis and crusted scabies, and could be an alternative option in ascariasis and Mansonella infections. Although these uses are already included in clinical guidelines, more trials are needed to increase their grade of evidence and to obtain their official approval. Concerning other minor uses such as the treatment of enterobiasis or against Trichuris trichiura, more research is still needed in order to test the real activity of ivermectin. The use of ivermectin in human medicine has shown an outstanding low rate of adverse reactions, with the exception of treatment of loiasis and onchocerciasis, where the death of a high microfilarial load may cause severe encephalopathy. However special attention must be paid to the emergence of the first documented cases of resistance in treatment of scabies. © 2012 Bentham Science Publishers. Source

Bussolotti F.,Chiba University
Journal of Electron Spectroscopy and Related Phenomena | Year: 2015

We developed ultrahigh sensitivity, low-background ultraviolet photoemission spectroscopy (UPS) technique which does not introduce detectable radiation damages into organic materials. The UPS allows to detect density of states of the order of ~1016 states eV-1 cm-3 even for radiation-sensitive organic films, this results being comparable to electrical measurements of charge trapping centers. In this review we introduce the method of ultrahigh sensitivity photoemission measurement and we present some results on the energy distribution of gap states in pentacene (Pn) films deposited on SiO2 and Au(111) substrate. For Pn/SiO2 thin film the results show that exposure to inert gas (N2 and Ar) atmosphere produces a sharp rise in gap states from 1016 to 1018 states eV-1 cm-3 and pushes the Fermi level closer to the valence band (0.15-0.17eV), as does exposure to O2 (0.20eV), while no such gas-induced effects are observed for Pn/Au(111) system. The results demonstrate that these gap states originate from small imperfections in the Pn packing structure, which are induced by gas penetration into the film through the Pn crystal grain boundaries. Similar results were obtained for CuPc/F16CuPc thin films, a prototypical example of donor/acceptor interface for photovoltaic application. © 2015 Elsevier B.V. Source

Endo O.,Tokyo University of Agriculture and Technology | Nakamura M.,Chiba University | Amemiya K.,High Energy Accelerator Research Organization
Journal of Electron Spectroscopy and Related Phenomena | Year: 2013

Depth analysis using X-ray absorption fine-structure spectroscopy at the near carbon K-edge (C K-NEXAFS) was performed for self-assembled monolayers of 4-methylbenzenethiol (4-MBT) and 4-ethylbenzenethiol (4-EBT) on Au(1 1 1). On the basis of the polarization dependence of π* resonance intensity, the benzene rings of 4-MBT and 4-EBT were found to be tilted by 30 ± 10 and 60 ± 5 with respect to the Au(1 1 1) surface, respectively. The spectra were separated into two components according to their depth by fitting the intensity decay curves of the electrons emitted by X-ray absorption. The spectra for lower segments exhibited bands at almost identical energies with different intensities depending on the polarization between 4-MBT and 4-EBT. In contrast, the spectra for upper segments including the alkyl groups showed a marked difference in the location of the σCC* resonance. The σCC* resonance of the ethyl group predominantly observed in the 15 incidence spectrum of 4-EBT indicated that the ethyl group was directed perpendicularly. © 2013 Elsevier B.V. Source

An understanding of the structure and behavior of electrolyte solutions in nanoenvironements is crucial not only for a wide variety of applications, but also for the development of physical, chemical, and biological processes. We demonstrate the structure and stability of electrolyte in carbon nanotubes using hybrid reverse Monte Carlo simulations of X-ray diffraction patterns. Hydrogen bonds between water are adequately formed in carbon nanotubes, although some hydrogen bonds are restricted by the interfaces of carbon nanotubes. The hydrogen bonding network of water in electrolyte in the carbon nanotubes is further weakened. On the other hand, formation of the ion hydration shell is significantly enhanced in the electrolyte in the carbon nanotubes in comparison to ion hydration in bulk electrolyte. The significant hydrogen bond and hydration shell formation are a result of gaining stability in the hydrophobic nanoenvironment. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Intermolecular/interionic vibrational spectra of mixtures composed of 1-methyl-3-n-octylimidazolium tetrafluoroborate ionic liquid and benzene at mole fractions of 0 (i.e., neat ionic liquid), 0.2, 0.4, 0.6, 0.8, and 1.0 (i.e., neat benzene) have been investigated using femtosecond Raman-induced Kerr effect spectroscopy. The line shape of the low-frequency Kerr spectra obtained from Fourier transform analyses of the Kerr transients is strongly dependent on the composition of the mixture. By comparing the experimental spectra to calculated spectra based on experimental spectra of the neat liquids, it is evident that the spectrum is not achieved by simply combining those of the neat liquids and taking the mole fraction into consideration. Close examination of the spectral comparison results in a microscopic picture involving specific stacking of imidazolium and benzene rings that is not sufficiently stable to affect the ring librations. The quantum chemistry calculation results also support this proposal. No clear correlation between the first moment of the spectrum and the bulk parameter (i.e., the square root of the surface tension divided by the liquid density), which occurs for neat liquids, is evident. © 2013 American Chemical Society. Source

Yoshida H.,Chiba University
Journal of Electron Spectroscopy and Related Phenomena | Year: 2015

Information about the unoccupied states is crucial to both fundamental and applied physics of organic semiconductors. However, there were no available experimental methods that meet the requirement of such research. In this review, we describe a new experimental method to examine the unoccupied states, called low-energy inverse photoemission spectroscopy (LEIPS). An electron having the kinetic energy lower than the damage threshold of organic molecules is introduced to a sample film, and an emitted photon in the near-ultraviolet range is detected with high resolution and sensitivity. Unlike the previous inverse photoemission spectroscopy, the sample damage is negligible and the overall resolution is a factor of two improved to 0.25. eV. Using LEIPS, electron affinity of organic semiconductor can be determined with the same precision as photoemission spectroscopy for ionization energy. The instruments including an electron source and photon detectors as well as application to organic semiconductors are presented. © 2015. Source

In the present study, the plant macrofossil stratigraphy of the Plio-Pleistocene sedimentary basins of Japan is reviewed, and the process of development of modern flora is discussed. Taxa endemic to the modern flora of central and south China became extinct, while plants that have been dominant in the recent cool-temperate and subarctic zones of Japan increased and/or emerged after the Late Pliocene. The floral change was stepwise, and the events were concentrated in transition periods of climatic fluctuation and/or in a downward shift of the glacial climate. These events are represented by the last occurrence of exotic taxa at 3.35Ma, 2.9Ma, 2.7-2.5Ma, 1.2Ma, 0.9Ma, 0.5Ma, and in the Late Pleistocene. Local extinctions occurred earlier in northern and inland basins, and the first appearance of plants dominant in modern cool-temperate and subarctic forests was dependent on the topography of mountains surrounding the basin. Geomorphological changes that were accompanied by mountain uplifts and sea level changes occurred in and around sedimentary basins during stage of floral changes. These alterations, along with climate changes, likely changed the habitats and migration routes of plants, which ultimately resulted in their extinction. © 2015 Elsevier Ltd and INQUA. Source

Ishida T.,Japan Institute for Molecular Science | Shirota H.,Chiba University
Journal of Physical Chemistry B | Year: 2013

The dynamical properties of a dicationic ionic liquid (IL), 1,6-bis(3-methylimidazolium-1-yl)hexane bis(trifluoromethylsulfonyl)amide ([C6(MIm)2][NTf2]2), compared to 1-methyl-3-propylimidazolium bis(trifluoromethylsulfonyl)amide ([C 3MIm][NTf2]), as its monocationic imidazolic counterpart, are studied by molecular dynamics simulations. We investigate relaxation processes of the polarizability anisotropy of the system and collective dynamics of both the ILs with mean-squared displacement (MSD), non-Gaussian parameter, and the intermediate scattering functions. The analyses of librational dynamics show that the difference of the Kerr spectra between the ILs could be mainly ascribed to the distinctive angular momentum of [C6(MIm) 2]2+ and [C3MIm]+ and related to the difference of relaxation behavior between [C6(MIm)2] 2+ and [C3MIm]+. Also, it is indicated that the librational dynamics of [NTf2]- indicate a common resonance-type sharp peak that corresponds to an intermolecular motion coupled to the vibrational mode intrinsic to [NTf2]-. In addition, it is exhibited from the total X-ray structure factors calculated for both of the ILs that the low-k peak at 0.20 Å-1 appears for [C 6(MIm)2][NTf2]2, while we do not see it for [C3MIm][NTf2]. We find that the contribution of the anion-cation and anion-anion correlations to the low-k peak is more significant than the cation-cation correlation. Therefore, it is suggested for [C6(MIm)2][NTf2]2 that dynamical heterogeneous behavior strongly correlates with structural variations or heterogeneity. © 2012 American Chemical Society. Source

Oohashi K.,Chiba University | Hirose T.,Japan Agency for Marine - Earth Science and Technology | Shimamoto T.,China Earthquake Administration
Journal of Geophysical Research: Solid Earth | Year: 2013

Graphite is a very low friction material, often enriched within fault zones due to mechanical or chemical processes. The effects of weak minerals on the strength of faults have been examined by friction experiments on bimineralic mixtures. However, previous experiments were conducted with limited shear strains, even though applied shear strains and textural developments had already been signaled as significant factors in the weakening of faults. We therefore conducted large-displacement, low- to high-velocity friction experiments with graphite-quartz gouges, to determine how much graphite is needed to reduce frictional strength, and to examine how textures contribute to the strength reduction of a mature fault at various slip rates. We found that the coefficients of friction of the gouges decrease nonlinearly with increasing graphite fraction for any given shear strain and slip rate, decreasing first with 5-20 vol% graphite, then reaching similar frictional levels to pure graphite with 30-50 vol% graphite. The nonlinear weakening trends can be fitted by sigmoidal curves. The weakening with 10-30 vol% graphite is associated with zones of slip-localization and the development of a graphite-lubricated penetrative slip surface(s). With increasing shear strain, the relationship between strength and graphite fraction evolves abruptly from an early gentle curve to a sigmoidal curve, and the frictional strength drops significantly even with small amounts of graphite (~10 vol%). Our results highlight the importance of shear strain and textural developments on weak faults, not only with respect to graphite, but also other fault lubricants such as the phyllosilicates. © 2013. American Geophysical Union. All Rights Reserved. Source

Masu H.,Chiba University | Tominaga M.,Tokushima Bunri University | Azumaya I.,Tokushima Bunri University
Crystal Growth and Design | Year: 2013

Eight cocrystals were formed from three adamantane-based bisphenols with structurally analogous skeletons and three bispyridines. Various 1D chains were constructed through intermolecular OH/N hydrogen bonds. Two crystals containing nonsubstituted bisphenols showed the formation of 1D zigzag chains, which were generated from two bisphenols and two bispyridines in one pitch of the 1D chain. Three crystals including chlorine-substituted bisphenols indicated the generation of 1D zigzag chains, and the pitches of these chains were longer than that of 1D chains composed of nonsubstituted bisphenols. Three crystals containing bromine-substituted bisphenols exhibited different shapes of 1D chains from other crystals, which were consisted of one bisphenol and one bispyridine in one pitch. These 1D chains assembled via intermolecular CH/O and/or CH/π interactions. The halogen substituents on the adamantane-based bisphenols influence on not only the shapes of 1D chains, but also 2D and 3D structures mainly due to steric hindrances. © 2013 American Chemical Society. Source

Park C.,Korea Institute of Machinery and Materials | Kim S.,Korea Institute of Machinery and Materials | Kim H.,Korea Institute of Machinery and Materials | Moriyoshi Y.,Chiba University
Energy | Year: 2012

Gasoline direct injection (GDI) systems have higher power and fuel efficiency than multi-point injection (MPI) systems. The direct injection of fuel into the combustion chamber leads to improved fuel economy because intake air is cooled by fuel evaporation. Direct fuel injection also improves knock resistance and volume efficiency. Furthermore, spray-guided direct injection (DI) combustion systems allow stratified lean combustion operation due to their ability to eliminate wall-wetting and form ignitable stratified mixtures near spark plugs.In this research, a spray-guided combustion system with a piezo-type gasoline direct injector was investigated for its applicability to stratified lean combustion engines. Tests were conducted at constant engine speeds and load conditions (2000 rpm, IMEP 0.28 MPa) that reflect typical operating conditions for passenger vehicles. Fuel economy and combustion stability were evaluated for various injection pressures at each excess air ratio. It is possible to create a sufficiently rich mixture for ignition in the vicinity of the spark plug, even under overall ultra-lean mixture conditions (λ = 3.0). Exhaust gas recirculation (EGR) and retarded ignition timing were considered to achieve a reduction in nitrogen oxide (NO x) emissions. EGR with optimized ignition timing was most effective when a spray-guided combustion system was employed. © 2012 Elsevier Ltd. Source

Hashimoto K.,Chiba University
Psychiatry and Clinical Neurosciences | Year: 2010

Mood disorders, such as major depressive disorder (MDD) and bipolar disorder (BPD), are the most prevalent psychiatric conditions, and are also among the most severe and debilitating. However, the precise neurobiology underlying these disorders is currently unknown. One way to combat these disorders is to discover novel biomarkers for them. The development of such biomarkers will aid both in the diagnosis of mood disorders and in the development of effective psychiatric medications to treat them. A number of preclinical studies have suggested that the brain-derived neurotrophic factor (BDNF) plays an important role in the pathophysiology of MDD. In 2003, we reported that serum levels of BDNF in antidepressant-naive patients with MDD were significantly lower than those of patients medicated with antidepressants and normal controls, and that serum BDNF levels were negatively correlated with the severity of depression. Additionally, we found that decreased serum levels of BDNF in antidepressant-naive patients recovered to normal levels associated with the recovery of depression after treatment with antidepressant medication. This review article will provide an historical overview of the role played by BDNF in the pathophysiology of mood disorders and in the mechanism of action of therapeutic agents. Particular focus will be given to the potential use of BDNF as a biomarker for mood disorders. BDNF is initially synthesized as a precursor protein proBDNF, and then proBDNF is proteolytically cleaved to the mature BDNF. Finally, future perspectives on the use of proBDNF as a novel biomarker for mood disorders will be discussed. Journal compilation © 2010 Japanese Society of Psychiatry and Neurology. Source

Ishikawa T.,Chiba University | Harwood L.M.,University of Reading
Synlett | Year: 2013

The term 'super base' is generally applied to ionic metal-containing bases that undergo irreversible proton abstraction. However, non-ionic powerful amine derivatives of amidines, guanidines, phosphazenes, and Verkade's bases with comparable or higher basicity to that of 1,8-bis(dimethylamino)naphthalene can all be arbitrarily classified as organic superbases. This Cluster contains manuscripts that present recent progress on organic superbases, including their applications in organic synthesis but, before proceeding, let us consider what class of molecule constitutes an organic superbase. © Georg Thieme Verlag Stuttgart New York. Source

Tao Y.,Shinshu University | Muramatsu H.,Shinshu University | Endo M.,Shinshu University | Kaneko K.,Chiba University
Journal of the American Chemical Society | Year: 2010

(Graph Presented) Highly pure double-walled carbon nanotubes synthesized by a catalytic chemical vapor deposition method have a quasi one-dimensional nanopore system. We determined these nanotubes' nanopore structures by means of molecular probe adsorption using N2 at 77 K, CO2 at 273 K, and water at 298, 308, and 318 K, as well as high-resolution transmission electron microscopy. The water vapor adsorption behavior of this system was quite unusual. At a lower relative pressure of P/P0 = 0.3-0.65, water filled the interstitial nanopores, and at relative pressures higher than this range, water also filled the interbundle nanopores. This study is the first to our knowledge that has provided direct evidence of water adsorption in hydrophobic nanospaces of highly pure double-walled carbon nanotubes. Copyright © 2010 American Chemical Society. Source

Ueda T.,Stanford University | Takaoka H.,Chiba University | Petrovitch I.,Northern Virginia Radiology Consultants | Rubin G.D.,Duke University
Radiology | Year: 2014

Purpose: To determine the prevalence of demonstrable stent-graft degradation by using three-dimensional computed tomographic (CT) angiography to assess endoleak and stent-graft migration after endovascular aortic aneurysm repair (EVAR). Materials and Methods: The institutional review board approved this retrospective study. Sixty-two consecutive patients with abdominal aortic aneurysm treated with the AneuRx stent-graft (Medtronic, Santa Rosa, Calif) were assessed between 0.5 and 9.5 years after EVAR (median, 5.1 years) for the presence of broken attachment sutures and metal-ring fractures by using CT angiography. The relative risk (RR) of delayed endoleak formation and endograft migration was calculated relative to the presence of suture breaks and metal-ring fractures. A two-tailed Fisher exact test was used to assess significant differences. Results: Suture breaks were observed in 55 of 62 subjects (89%), including 37 minor breaks (60%) and 18 major breaks (29%). Metal-ring fractures were observed in 11 of 62 subjects (18%). Twenty-seven endoleaks were observed in 24 of 62 subjects (39%) and were categorized as type I in seven of 27 (11%), type II in 16 of 27 (26%), and type III in four of 27 (6%). Major suture breaks were associated with six of seven (86%) delayed type I endoleaks (RR = 19.4, P = .003), and metal-ring fractures were associated with four of seven (57%) delayed type I endoleaks (RR = 6.2, P = .015) and three of four (75%) type III endoleaks (RR = 13.9, P = 003). Migration was observed in 15 of 62 patients (24%) and was associated with major suture breaks in 10 of 15 patients (67%, RR = 4.5, P = .001) and with metal-ring fractures in five of 11 patients (45%, RR = 4.1, P = .003). Repeat interventions were performed in 15 patients. Conclusion: Major suture breaks and metal-ring fractures are demonstrated with CT and are associated with delayed type I and III endoleaks and with stent-graft migration after EVAR. © RSNA, 2014. Source

Nagase A.,Chiba University | Dunnett N.,University of Sheffield
Urban Forestry and Urban Greening | Year: 2013

Dwarf geophytes have great potential for use on extensive green roofs because they often come from arid areas and can survive dry and hot summer in a dormant state. However, there has been little research regarding geophytes on green roofs. This experiment was conducted to study the performance of 26 species of geophytes on a green roof during 2005-2006 in Sheffield, UK. The geophytes were grown at two substrate depths (5. cm and 10. cm) of substrate on a green roof without irrigation. To investigate the susceptibility of geophytes to competition from a covering of permanent plants, the geophytes were grown with or without a surface vegetation layer of Sedum album. Overall, the growth, survival rate, regeneration and flowering of geophytes were more successful at a substrate depth of 10. cm than of 5. cm, probably because of improved moisture retention, fewer temperature fluctuations and the protection from digging by animals. The flowering period was limited to spring, therefore, it is recommended to combine with other plant species such as covering plants. Geophyte species did not compete much with S. album and Sedum cover had no significant effects on the growth, survival rate, regeneration and flowering of geophytes in most species. Iris bucharica, Muscari azureum, Tulipa clusiana var. chrysantha, Tulipa humilis, Tulipa tarda and Tulipa turkestanica had good performance at the substrate depth of 5. cm. In addition, Narcissus cyclamineus 'February gold' and Tulipa urumiensis exhibited a successful performance at the substrate depth of 10. cm. © 2013 Elsevier GmbH. Source

This study is concerned with the dynamic risk-analysis fornite state Markov decision processes. As a measure of risk, we consider conditional value-at-risk(CVaR) for the real value of the discounted total reward from a policy, under whose criterion risk optimal or deterministic policies are de ned. The risk problem is equivalently rede ned as a non-linear optimization problem on the attainable set of the distribution functions for the real values over all policies. Showing the weak-continuity of CVaR on the space of attainable distribution functions, the mathematical existence theorem of optimal policies are proved throughout the discussion of convex analysis and weak-compactness. © 2013 World Academic Press, UK. All rights reserved. Source

Karata K.,U.S. National Institutes of Health | Karata K.,Chiba University | Vaisman A.,U.S. National Institutes of Health | Goodman M.F.,University of Southern California | Woodgate R.,U.S. National Institutes of Health
DNA Repair | Year: 2012

Most damage induced mutagenesis in Escherichia coli is dependent upon the UmuD'2C protein complex, which comprises DNA polymerase V (pol V). Biochemical characterization of pol V has been hindered by the fact that the enzyme is notoriously difficult to purify, largely because overproduced UmuC is insoluble. Here, we report a simple and efficient protocol for the rapid purification of milligram quantities of pol V from just 4. L of bacterial culture. Rather than over producing the UmuC protein, it was expressed at low basal levels, while UmuD'2 was expressed in trans from a high copy-number plasmid with an inducible promoter. We have also developed strategies to purify the β-clamp and γ-clamp loader free from contaminating polymerases. Using these highly purified proteins, we determined the cofactor requirements for optimal activity of pol V in vitro and found that pol V shows robust activity on an SSB-coated circular DNA template in the presence of the β/γ-complex and a RecA nucleoprotein filament (RecA*) formed in trans. This strong activity was attributed to the unexpectedly high processivity of pol V Mut (UmuD'2C{dot operator}RecA{dot operator}ATP), which was efficiently recruited to a primer terminus by SSB. © 2012. Source

Togawa Y.,Osaka Prefecture University | Togawa Y.,Japan Science and Technology Agency | Kousaka Y.,Aoyama Gakuin University | Nishihara S.,Hiroshima University | And 4 more authors.
Physical Review Letters | Year: 2013

We investigate the interlayer magnetoresistance (MR) along the chiral crystallographic axis in the hexagonal chiral magnet CrNb3S 6. In a region below the incommensurate-commensurate phase transition between the chiral soliton lattice and the forced ferromagnetic state, a negative MR is obtained in a wide range of temperature, while a small positive MR is found very close to the Curie temperature. Normalized data of the negative MR almost falls into a single curve and is well fitted by a theoretical equation of the soliton density, meaning that the origin of the MR is ascribed to the magnetic scattering of conduction electrons by a nonlinear, periodic, and countable array of magnetic soliton kinks. © 2013 American Physical Society. Source

Tsubota K.-I.,Chiba University | Wada S.,Osaka University
Physical Review E - Statistical, Nonlinear, and Soft Matter Physics | Year: 2010

A two-dimensional computer simulation model was proposed for tank-treading and tumbling motions of an elastic biconcave red blood cell (RBC) under steady shear flow. The RBC model consisted of an outer cellular membrane and an inner fluid; the membrane's elastic properties were modeled by springs for stretch/compression and bending to consider the membrane's natural state in a practical manner. Membrane deformation was coupled with incompressible viscous flow of the inner and outer fluids of the RBC using a particle method. The proposed simulation model was capable of reproducing tank-treading and tumbling motions of an RBC along with rotational oscillation, which is the transition between the two motions. In simulations using the same initial RBC shape with different natural states of the RBC membrane, only tank-treading motion was exhibited in the case of a uniform natural state of the membrane, and a nonuniform natural state was necessary to generate the rotational oscillation and tumbling motion. Simulation results corresponded to published data from experimental and computational studies. In the range of simulation parameters considered, the relative membrane elastic force versus fluid viscous force was ∼1 at the transition when the natural state nonuniformity was taken into account in estimating the membrane elastic force. A combination of natural state nonuniformity and elastic spring constant determined that change in the RBC deformation at the transition is that from a large compressive deformation to no deformation, such as rigid body. © 2010 The American Physical Society. Source

Sakamoto S.,University of Kentucky | Sakamoto S.,Chiba University | Schwarze S.,University of Kentucky | Kyprianou N.,University of Kentucky
European Urology | Year: 2011

Background: Quinazoline-based α1-adrenoceptor antagonists suppress tumor growth by inducing apoptosis via an α1-adrenoceptor-independent action. Anoikis is a unique mode of apoptosis consequential to insufficient cell-matrix interactions. Objective: This study investigated the apoptotic effect of novel quinazoline-based compounds on human renal cancer cells. Design, setting, and participants: Two cell lines were used: renal cell carcinoma (RCC) 786-0, harboring a von Hippel-Lindau (VHL) tumor-suppressor gene mutation with a highly angiogenic phenotype, and Caki cells (no VHL mutation). Measurements: The lead compound DZ-50 (10 μM) led to significant inhibition of tumor-cell adhesion, migration, and invasion at a lower dose than doxazosin (25 μM) in both RCC lines. Results and limitations: Doxazosin induced death-receptor- mediated apoptosis, while DZ-50 led to anoikis via targeting of the focal adhesion complex and AKT signaling that subsequently increased RCC susceptibility to caspase-8-mediated apoptosis. Both quinazoline compounds, doxazosin and DZ-50, significantly reduced RCC metastatic potential in vivo. Conclusions: Quinazoline-based drugs trigger anoikis in RCC by targeting the focal adhesion survival signaling. This potent antitumor action against human RCC suggests a novel quinazoline-based therapy targeting renal cancer. © 2011 Published by Elsevier B.V. Source

Kondo K.-I.,Chiba University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2013

In order to understand the so-called decoupling solution for gluon and ghost propagators in QCD, we give a nonperturbative construction of a massive vector field describing a non-Abelian massive spin-one particle, which has the correct physical degrees of freedom and is invariant under a modified Becchi-Rouet-Stora-Tyutin transformation, in a massive Yang-Mills model without the Higgs field, i.e., the Curci-Ferrari model. The resulting non-Abelian massive vector boson field is written by using a nonlinear but local transformation from the original fields in the Curci-Ferrari model. As an application, we write down a local mass term for the Yang-Mills field and a dimension-two condensate, which are exactly invariant under the modified Becchi-Rouet-Stora-Tyutin transformation, Lorentz transformation, and color rotation. © 2013 American Physical Society. Source

Tokoyoda K.,German Rheumatism Research Center Berlin | Tokoyoda K.,Chiba University | Radbruch A.,German Rheumatism Research Center Berlin
Cellular and Molecular Life Sciences | Year: 2012

Established views on the maintenance of immunological memory have been challenged recently by the description of memory plasma cells and memory T helper (Th) lymphocytes residing in the bone marrow (BM) in dedicated survival niches, resting in terms of proliferation and migration. While memory plasma cells are no longer reactive to antigen, memory Th lymphocytes are in a state of attentive rest, and can be reactivated fast and efficiently. Here, we discuss the signals controlling these resting states, which the memory lymphocytes receive from their microenvironment. © 2011 Springer Basel AG. Source

OBJECTIVE: The World Health Organization 2010 classification divides pancreatic neuroendocrine tumors (p-NETs) entity to well-differentiated neuroendocrine tumors (NET) and poorly differentiated neuroendocrine carcinomas (NEC) by Ki-67 index. The aim of this study is elucidate the pathophysiology and tumor biology of p-NETs. METHODS: We assessed the expression of transcription factors sex determining region Y-box 2 (SOX2) and pancreatic and duodenal homeobox 1 (Pdx1)) essential for the normal fetal development of pancreatic neuroendocrine cells in 46 surgically resected p-NETs by immunohistochemistry. The relationship of expression levels of these factors and clinicopathological factors were analyzed. RESULTS: SOX2 was positive in 6 p-NETs (13.0%). Five of 7 NEC patients showed positive for SOX2. SOX2 was highly (sensitivity 71%) and specifically (specificity 97%) expressed in NEC. Patients with SOX2 positive p-NET showed the significantly shorter disease-free and overall survival than patients with SOX2 negative p-NET. High Pdx1 expression was seen in 25 p-NET patients (54.3%). None of the NEC patients showed high Pdx1 expression. There was a significant reverse correlation between SOX2 and Pdx1 expression. CONCLUSIONS: The expression patterns of SOX2 and Pdx1 highly correlated with prognosis of p-NETs. These expression patterns may represent the biological and pathophysiological difference of p-NETs and indicate the origin of tumor. © 2015 Wolters Kluwer Health, Inc. All rights reserved. Source

Ozen C.,Yale University | Ozen C.,Kadir Has University | Alhassid Y.,Yale University | Nakada H.,Chiba University
Physical Review Letters | Year: 2013

Heavy nuclei exhibit a crossover from vibrational to rotational collectivity as the number of neutrons or protons increases from shell closure towards midshell, but the microscopic description of this crossover has been a major challenge. We apply the shell model Monte Carlo approach to families of even-even samarium and neodymium isotopes and identify a microscopic signature of the crossover from vibrational to rotational collectivity in the low-temperature behavior of J2T, where J is the total spin and T is the temperature. This signature agrees well with its values extracted from experimental data. We also calculate the state densities of these nuclei and find them to be in very good agreement with experimental data. Finally, we define a collective enhancement factor from the ratio of the total state density to the intrinsic state density as calculated in the finite-temperature Hartree-Fock-Bogoliubov approximation. The decay of this enhancement factor with excitation energy is found to correlate with the pairing and shape phase transitions in these nuclei. © 2013 American Physical Society. Source

Minami Y.,Yokohama National University | Kurihara T.,University of Tokyo | Yamaguchi K.,University of Tokyo | Nakajima M.,Chiba University | Suemoto T.,University of Tokyo
Applied Physics Letters | Year: 2013

We introduce a simple and efficient method of enhancing the terahertz field in an air plasma produced by two-color laser pulses, by inserting a specially designed dual-wavelength wave plate between the non-linear optical crystal and the plasma. Adjusting the polarization of the two laser pulses yielded an electric field of 1.4 MV/cm, which was 1.7 times as intense as that obtained from the unmodified system. Additionally, taking a dispersion of the group velocities of the two-color laser pulses into account, we discussed the validity of the enhancement factor. © 2013 American Institute of Physics. Source

Furuya M.,Kanazawa University | Nakatani Y.,Chiba University
Journal of Clinical Pathology | Year: 2013

Birt-Hogg-Dubé syndrome (BHD) is an autosomal dominant inherited disorder characterised by fibrofolliculomas, renal tumours, pulmonary cysts and pneumothorax. The pulmonary cysts and repeated episodes of pneumothorax are the clinical hallmarks for discovering families affected by the syndrome. This disorder is caused by mutations in the gene coding for folliculin (FLCN). FLCN forms a complex with FLCN-interacting protein 1 (FNIP1) and FNIP2 (also known as FNIPL), and the complex cross-talks with signalling molecules such as 50-AMP-activated protein kinase (AMPK) and the mammalian target of rapamycin (mTOR). Heterozygous Flcn knockout mice and rats with Flcn gene mutations develop renal cysts, adenomas and/or carcinomas. These findings suggest that FLCN functions as a tumour suppressor that inhibits renal carcinogenesis. However, the mechanisms of the formation of pulmonary cysts and pneumothorax associated with heterozygous mutations in FLCN are poorly understood. Resected lung specimens from patients with BHD are often misdiagnosed by pathologists as non-specific blebs or bullae or emphysema, and patients with BHD who have pulmonary cysts and repeated pneumothorax frequently do not receive appropriate medical investigations. This review discusses the clinical and pathological features of lungs of patients with BHD, focusing on the diagnostic pathology and possible mechanisms of cyst formation. Source

In this study, we investigated segment lengthening in spontaneous Japanese based on a quantitative analysis of a large-scale corpus, focusing on the following three locations at which lengthening frequently occurs: the final segments of (i) clause-initial preface tokens (fillers and conjunctions), (ii) clause-initial wa-marked topic phrases, and (iii) clause-final particles. Two cognitive factors, namely clause complexity and boundary depth, were precisely analyzed using statistical models that also accounted for several phonological and syntactic factors. The results showed that in addition to the reliably strong effects of some phonological factors such as the presence of a following pause and the presence of boundary pitch movement, the effects of two cognitive factors were also evident. The way in which lengthening is related to the cognitive factors, however, varies significantly by location and token type. Lengthening of clause-final particles was affected by boundary depth, while lengthening of the topic marker wa of clauseinitial topic phrases was influenced by clause complexity. Lengthening of the filler e was affected by both factors. A significant interaction between the two factors was also observed for the filler ano. We discuss the implications of these results as well as agendas for improving the current analysis. Source

Tewari R.K.,Chungbuk National University | Tewari R.K.,Chiba University | Paek K.-Y.,Chungbuk National University
Journal of Plant Growth Regulation | Year: 2011

We evaluated the involvement of nitric oxide (NO) in salicylic acid (SA)-induced accumulation of ginsenoside in adventitious roots of Panax ginseng and its mediation by reactive oxygen species (ROS). Related effects of SA on components of the antioxidant system were also sought. Adventitious roots of P. ginseng were grown in suspension culture for 3 weeks in MS medium and treated over 5 days with SA (100 μM) alone, SA in combination with the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), or PTIO alone. Nitric oxide, the superoxide anion (O2·-), H2O2, nitrite, nonprotein thiol, and ascorbate were monitored together with ginsenoside, NADPH oxidase activity, and several antioxidant enzymes. Salicylic acid did not inhibit root growth but induced accumulation of ginsenoside, lipid peroxidation, and generation of NO and O2·-. It also enhanced activities of NADPH oxidase, superoxide dismutase, catalase, and peroxidase, including ascorbate peroxidase. These effects were suppressed by PTIO. Salicylic acid also decreased glutathione reductase activity. Inclusion of PTIO with SA decreased the activity of glutathione reductase further. Treatment with SA plus PTIO also decreased nonprotein thiol and ascorbate contents but caused nitrite to overaccumulate. Salicylic acid applied to adventitious roots in culture induced accumulation of ginsenoside in an NO-dependent manner that was mediated by the associated increases in O2·-, which gave other antioxidant responses that were dependent on NO. © 2011 Springer Science+Business Media, LLC. Source

Hayati M.,Razi University | Lotfi A.,Razi University | Kazimierczuk M.K.,Wright State University | Sekiya H.,Chiba University
IEEE Transactions on Power Electronics | Year: 2013

This paper presents analytical expressions for the class-E power amplifier with MOSFET linear gate-to-drain and nonlinear drain-to-source parasitic capacitances at any duty ratio. The maximum operating frequency, output power capability, and element values as functions of the duty ratio are obtained. The element values are directly dependent upon the selection of duty ratio and require a careful duty ratio selection to minimize component power losses and to maximize the total efficiency. Two design examples at 25 and 9 W output power at 4-MHz operating frequency along with the PSpice-simulation and experimental waveforms are presented. It is shown from the derived expressions that the slope of the voltage across the MOSFET gate-to-drain parasitic capacitance during the switch-off state as a function of the duty ratio affects the switch-voltage waveform. Therefore, it is possible to achieve the required peak switch voltage and the class-E ZVS/ZVDS conditions simultaneously by adjusting the duty ratio. The theoretical results and PSpice simulations agreed with experimental results quantitatively, which shows the validity of the presented analysis. © 1986-2012 IEEE. Source

Katsuura T.,Chiba University
Journal of physiological anthropology | Year: 2012

It has been assumed that light with a higher irradiance of pulsed blue light has a much greater influence than that of light with a lower irradiance of steady blue light, although they have the same multiplication value of irradiance and duration. We examined the non-visual physiological effects of blue pulsed light, and determined whether it is sensed visually as being blue. Seven young male volunteers participated in the study. We placed a circular screen (diameter 500 mm) in front of the participants and irradiated it using blue and/or white light-emitting diodes (LEDs), and we used halogen lamps as a standard illuminant. We applied three steady light conditions of white LED (F0), blue LED + white LED (F10), and blue LED (F100), and a blue pulsed light condition of a 100-μs pulse width with a 10% duty ratio (P10). The irradiance of all four conditions at the participant's eye level was almost the same, at around 12 μW/cm2. We measured their pupil diameter, recorded electroencephalogram readings and Kwansei Gakuin Sleepiness Scale score, and collected subjective evaluations. The subjective bluish score under the F100 condition was significantly higher than those under other conditions. Even under the P10 condition with a 10% duty ratio of blue pulsed light and the F10 condition, the participant did not perceive the light as bluish. Pupillary light response under the P10 pulsed light condition was significantly greater than under the F10 condition, even though the two conditions had equal blue light components. The pupil constricted under the blue pulsed light condition, indicating a non-visual effect of the lighting, even though the participants did not perceive the light as bluish. Source

Mizuta A.,High Energy Accelerator Research Organization | Mizuta A.,Chiba University | Nagataki S.,Kyoto University | Aoi J.,Kyoto University
Astrophysical Journal | Year: 2011

In this study, the light curves and spectrum of the photospheric thermal radiation from ultrarelativistic gamma-ray burst (GRB) jets are calculated using two-dimensional relativistic hydrodynamic simulations of jets from a collapsar. As the jet advances, the density around the head of the jet decreases, and its Lorentz factor reaches as high as 200 at the photosphere and 400 inside the photosphere. For an on-axis observer, the photosphere appears concave due to the low density and high beaming factor of the jet. The luminosity varies because of the abrupt change in the position of the photosphere due to the internal structure of the jet. Comparing our results with GRB090902B, the flux level of the thermal-like component is similar to our model, although the peak energy appears slightly higher (but still within a factor of two). From the comparison, we estimate that the bulk Lorentz factor of GRB 090902B is Γ ∼ 2.4 × 102(r/1012 cm), where r is the radius of the photosphere. The spectrum for an on-axis observer is harder than that for an off-axis observer. There is a time lag of a few seconds for high energy bands in the light curve. This may be the reason for the delayed onset of GeV emission seen in GRB 080916C. The spectrum below the peak energy is a power law and the index is 2.3-2.6, which is softer than that of a single temperature Planck distribution but still harder than that of the typical value of the observed spectrum. © 2011. The American Astronomical Society. All rights reserved. Source

Isono S.,Chiba University | Greif R.,University of Bern | Mort T.C.,University of Connecticut
Anaesthesia | Year: 2011

We highlight the areas we think important for future development of the subspeciality. The ultimate goal is to improve patient care and safety and to do this, we need to identify how and where episodes of harm arise. Simply continuing with current practice does not represent the best path towards our ultimate goal; objective evidence is needed to inform changes in practice. © 2011 The Association of Anaesthetists of Great Britain and Ireland. Source

Photocatalytic reduction of carbon dioxide to fuels using solar energy is an attractive option for simultaneously capturing this major greenhouse gas and solving the shortage of sustainable energy. Efforts to demonstrate the photocatalytic reduction of CO 2 are reviewed herein. Although the photocatalytic results depended on the reaction conditions, such as the incident/absorbing light intensity from the sun or a simulated solar light source, the performance of different systems is compared. When the reactants included CO 2 and water, it was necessary to determine whether the products were derived from CO 2 and not from impurities that accumulated on/in the catalysts as a result of washing, calcination, or pretreatment in a moist environment. Isotope labeling of 13CO 2 was effective for this evaluation using Fourier-transform infrared (FTIR) spectroscopy and mass spectrometry (MS). Comparisons are limited to reports in which the reaction route was verified spectroscopically, the C source was traced isotopically, or sufficient kinetic analyses were performed to verify the photocatalytic events. TiO 2 photocatalytically produced methane at the rate of ∼0.1μmolh -1g cat -1. In aqueous solutions, formic acid, formaldehyde, and methanol were also produced. When TiO 2 was atomically dispersed in zeolites or ordered mesoporous SiO 2 and doped with Pt, Cu, N, I, CdSe, or PbS, the methane and CO formation rates were greater, reaching 1-10μmolh -1g cat -1. As for semiconductors other than TiO 2, CdS, SiC, InNbO 4, HNb 3O 8, Bi 2WO 6, promoted NaNbO 3, and promoted Zn 2GeO 4 produced methane or methanol at rates of 1-10μmolh -1g cat -1, and promoted A IILa 4Ti 4O 15 produced CO at a rate greater than 10μmolh -1g cat -1, in addition to the historically known ZnO and GaP (formaldehyde and methanol formation). The photocatalytic reduction of CO 2 was also surveyed with hydrogen, because hydrogen can be obtained from water photosplitting by utilizing natural light. CO was formed at a rate of ∼1μmolh -1g cat -1 using TiO 2, ZrO 2, MgO, and Ga 2O 3, whereas both CO and methanol were formed at a rate of 0.1-1μmolh -1g cat -1 using layered-double hydroxides consisting of Zn, Cu, Al, and Ga. When hydrogen is used, in addition to identifying the origin of the carbon, it is critical to confirm that the products are photocatalytically formed, not thermally produced via CO 2 hydrogenation. The feasibility of the strategy involving the recycling of a sacrificial electron donor and the direct supply of protons and electrons released from water oxidation catalysts to photocatalysts for the reduction of CO 2 to fuels has been demonstrated. However, based on the results obtained to date, it is clear that the practical use of the photocatalytic reduction of CO 2 as one possible solution for global warming and the world's energy problems requires the development of more efficient photocatalysts. © 2012 Elsevier B.V.. Source

Yamazaki F.,Chiba University | Zavala C.,Peruvian National University of Engineering
Journal of Disaster Research | Year: 2013

This project conducts comprehensive research on earthquake and tsunami disaster mitigation in Peru in the framework of "Science and Technology Research Partnership for Sustainable Development (SATREPS)," sponsored by Japan Science and Technology Agency (JST) and Japan International Cooperation Agency (JICA). The project focuses on five research fields, i.e., seismic motion and geotechnical, tsunami, buildings, damage assessment, and disaster mitigation planning. Almost three years have passed since the five-year project started in March 2010. During this period, researchers in different fields from Japan and Peru collaborate to achieve the overall objectives of the project. This paper summarizes the research framework and progress of the JST-JICA project on earthquake and tsunami disaster mitigation technology in Peru. Source

Yamashiro S.,Scripps Research Institute | Gokhin D.S.,Scripps Research Institute | Kimura S.,Chiba University | Nowak R.B.,Scripps Research Institute | Fowler V.M.,Scripps Research Institute
Cytoskeleton | Year: 2012

Tropomodulins are a family of four proteins (Tmods 1-4) that cap the pointed ends of actin filaments in actin cytoskeletal structures in a developmentally regulated and tissue-specific manner. Unique among capping proteins, Tmods also bind tropomyosins (TMs), which greatly enhance the actin filament pointed-end capping activity of Tmods. Tmods are defined by a TM-regulated/Pointed-End Actin Capping (TM-Cap) domain in their unstructured N-terminal portion, followed by a compact, folded Leucine-Rich Repeat/Pointed-End Actin Capping (LRR-Cap) domain. By inhibiting actin monomer association and dissociation from pointed ends, Tmods regulate actin dynamics and turnover, stabilizing actin filament lengths and cytoskeletal architecture. In this review, we summarize the genes, structural features, molecular and biochemical properties, actin regulatory mechanisms, expression patterns, and cell and tissue functions of Tmods. By understanding Tmods' functions in the context of their molecular structure, actin regulation, binding partners, and related variants (leiomodins 1-3), we can draw broad conclusions that can explain the diverse morphological and functional phenotypes that arise from Tmod perturbation experiments in vitro and in vivo. Tmod-based stabilization and organization of intracellular actin filament networks provide key insights into how the emergent properties of the actin cytoskeleton drive tissue morphogenesis and physiology. © 2012 Wiley Periodicals, Inc. Source

Stoeber J.,University of Kent | Kobori O.,Chiba University | Brown A.,University of Kent
Assessment | Year: 2014

Perfectionism cognitions capture automatic perfectionistic thoughts and have explained variance in psychological adjustment and maladjustment beyond trait perfectionism. The aim of the present research was to investigate whether a multidimensional assessment of perfectionism cognitions has advantages over a unidimensional assessment. To this aim, we examined in a sample of 324 university students how the Perfectionism Cognitions Inventory (PCI) and the Multidimensional Perfectionism Cognitions Inventory (MPCI) explained variance in positive affect, negative affect, and depressive symptoms when factor or subscale scores were used as predictors compared to total scores. Results showed that a multidimensional assessment (PCI factor scores, MPCI subscale scores) explained more variance than a unidimensional assessment (PCI and MPCI total scores) because, when the different dimensions were entered simultaneously as predictors, perfectionistic strivings cognitions and perfectionistic concerns cognitions acted as mutual suppressors thereby increasing each others’ predictive validity. With this, the present findings provide evidence that—regardless of whether the PCI or the MPCI is used—a multidimensional assessment of perfectionism cognitions has advantages over a unidimensional assessment in explaining variance in psychological adjustment and maladjustment. © The Author(s) 2014. Source

Senju Y.,University of Tokyo | Itoh Y.,University of Tokyo | Takano K.,University of Tokyo | Hamada S.,University of Tokyo | And 3 more authors.
Journal of Cell Science | Year: 2011

Caveolae are flask-shaped invaginations of the plasma membrane that are associated with tumor formation, pathogen entry and muscular dystrophy, through the regulation of lipids, signal transduction and endocytosis. Caveolae are generated by the fusion of caveolin-1-containing vesicles with the plasma membrane, which then participate in endocytosis via dynamin. Proteins containing membrane-sculpting F-BAR (or EFC) domains organize the membrane in clathrin-mediated endocytosis. Here, we show that the FBAR protein PACSIN2 sculpts the plasma membrane of the caveola. The PACSIN2 F-BAR domain interacts directly with caveolin-1 by unmasking autoinhibition of PACSIN2. Furthermore, the membrane invaginations induced by the PACSIN2 F-BAR domain contained caveolin-1. Knockdown of PACSIN2 resulted in abnormal morphology of caveolin-1-associated plasma membranes, presumably as a result of decreased recruitment of dynamin-2 to caveolin-1. These results indicate that PACSIN2 mediates membrane sculpting by caveolin-1 in caveola morphology and recruits dynamin-2 for caveola fission. © 2011. Published by The Company of Biologists Ltd. Source

Yamazaki S.,Japan Science and Technology Agency | Ema H.,Tokyo Medical University | Karlsson G.,Lund University | Yamaguchi T.,Japan Science and Technology Agency | And 9 more authors.
Cell | Year: 2011

Hematopoietic stem cells (HSCs) reside and self-renew in the bone marrow (BM) niche. Overall, the signaling that regulates stem cell dormancy in the HSC niche remains controversial. Here, we demonstrate that TGF-β type II receptor-deficient HSCs show low-level Smad activation and impaired long-term repopulating activity, underlining the critical role of TGF-β/Smad signaling in HSC maintenance. TGF-β is produced as a latent form by a variety of cells, so we searched for those that express activator molecules for latent TGF-β. Nonmyelinating Schwann cells in BM proved responsible for activation. These glial cells ensheathed autonomic nerves, expressed HSC niche factor genes, and were in contact with a substantial proportion of HSCs. Autonomic nerve denervation reduced the number of these active TGF-β-producing cells and led to rapid loss of HSCs from BM. We propose that glial cells are components of a BM niche and maintain HSC hibernation by regulating activation of latent TGF-β. © 2011 Elsevier Inc. Source

Epidemiological evidence suggests there are significant links between obesity and obstructive sleep apnoea (OSA), with a particular emphasis on the importance of fat distribution in the development of OSA. In patients with OSA, the structure of the pharyngeal airway collapses. A collapsible tube within a rigid box collapses either due to decreased intraluminal pressure or increased external tissue pressure (i.e. reduction in transmural pressure), or due to reduction in the longitudinal tension of the tube. Accordingly, obesity should structurally increase the collapsibility of the pharyngeal airway due to excessive fat deposition at two distinct locations. In the pharyngeal airway region, excessive soft tissue for a given maxillomandibular enclosure size (upper airway anatomical imbalance) can increase tissue pressure surrounding the pharyngeal airway, thereby narrowing the airway. Even mild obesity may cause anatomical imbalance in individuals with a small maxilla and mandible. Lung volume reduction due to excessive central fat deposition may decrease longitudinal tracheal traction forces and pharyngeal wall tension, changing the 'tube law' in the pharyngeal airway (lung volume dependence of the upper airway). The lung volume dependence of pharyngeal airway patency appears to contribute more significantly to the development of OSA in morbidly obese, apnoeic patients. Neurostructural interactions required for stable breathing may be influenced by obesity-related hormones and cytokines. Accumulating evidence strongly supports these speculations, but further intensive research is needed. © 2011 Asian Pacific Society of Respirology. Source

Ohba T.,Chiba University | Chaban V.V.,University of Southern Denmark
Journal of Physical Chemistry B | Year: 2014

We report a combined experimental (X-ray diffraction) and theoretical (molecular dynamics, hybrid density functional theory) study of 1-ethyl-3-methylimidazolium chloride, [C2C1MIM][Cl], inside carbon nanotubes (CNTs). We show that despite its huge viscosity [C 2C1MIM][Cl] readily penetrates into 1-3 nm wide CNTs at slightly elevated temperatures (323-363 K). Molecular simulations were used to assign atom-atom peaks. Experimental and simulated structures of RTIL inside CNT and in bulk phase are in good agreement. We emphasize a special role of the CNT-chloride interactions in the successful adsorption of [C2C 1MIM][Cl] on the inner sidewalls of 1-3 nm carbon nanotubes. © 2014 American Chemical Society. Source

Ashida H.,Tokyo Medical University | Mimuro H.,Tokyo International University | Sasakawa C.,Tokyo Medical University | Sasakawa C.,Nippon Institute for Biological Science | Sasakawa C.,Chiba University
Frontiers in Immunology | Year: 2015

The intestinal epithelium deploys multiple defense systems against microbial infection to sense bacterial components and danger alarms, as well as to induce intracellular signal transduction cascades that trigger both the innate and the adaptive immune systems, which are pivotal for bacterial elimination. However, many enteric bacterial pathogens, including Shigella, deliver a subset of virulence proteins (effectors) via the type III secretion system (T3SS) that enable bacterial evasion from host immune systems; consequently, these pathogens are able to efficiently colonize the intestinal epithelium. In this review, we present and select recently discovered examples of interactions between Shigella and host immune responses, with particular emphasis on strategies that bacteria use to manipulate inflammatory outputs of host-cell responses such as cell death, membrane trafficking, and innate and adaptive immune responses. © 2015 Ashida, Mimuro and Sasakawa. Source

Horie K.,Japan National Institute of Polar Research | Hokada T.,Japan National Institute of Polar Research | Hiroi Y.,Chiba University | Motoyoshi Y.,Japan National Institute of Polar Research | Shiraishi K.,Japan National Institute of Polar Research
Gondwana Research | Year: 2012

U-Pb zircon geochronology of 6 samples collected from Fyfe Hills (2 felsic orthogneisses and 1 quartzo-feldspathic gneiss) and Mt. Cronus (1 quartzo-feldspathic gneiss and 2 quartzites) in the western part of the Napier Complex, East Antarctica, revealed an Archaean-Proterozoic history ranging from 3128 to 1824. Ma. The absence of ancient evidence >. 3800-3600. Ma indicates that these ages were not always dominant in these two areas. The 3128-2580. Ma protolith ages are similar to those of other areas (e.g., Mt. Riiser-Larsen, Tonagh Island), while the magmatic protolith age of 2741. Ma obtained for the Fyfe Hills orthogneiss is a new component of the Archaean magmatic protolith in the Napier Complex. Metamorphic overgrowth or recrystallized zircons yielded systematic disconformable ages for both Fyfe Hills (>. 2518. Ma) and Mt. Cronus (~. 2490. Ma). The presence of 2580. Ma inherited zircons provides important constraints that place the ultrahigh temperature metamorphic peak later than 2580. Ma. The post metamorphic ages suggest local fluid infiltration or local deformation event(s). © 2011 International Association for Gondwana Research. Source

Sri Sumantyo J.T.,Chiba University | Shimada M.,Japan Aerospace Exploration Agency | Mathieu P.-P.,European Space Agency | Abidin H.Z.,Bandung Institute of Technology
IEEE Transactions on Geoscience and Remote Sensing | Year: 2012

In this paper, the long-term consecutive differential interferometric synthetic aperture radar (SAR) technique is used to measure the volume change during land deformation. This technique was used to investigate the subsidence of Bandung city, Indonesia, by assessing the data from two Japanese L-band spaceborne SARs (Japanese Earth Resources Satellite 1 SAR and Advanced Land Observation Satellite Phased Array type L-band Synthetic Aperture Radar) during the periods of 1993-1997 and 2007-2010. The results are confirmed using GPS observation data, ground survey data, local statistics, ground water level trend data, and the geological formation of the study area. The obtained results reveal a close correlation between the subsidence measurements and changes in the ground water level due to water pumping, population growth, industry growth, and urbanization of the study area. © 2011 IEEE. Source

Misawa S.,Chiba University
Brain and Nerve | Year: 2014

The diagnosis of amyotrophic lateral sclerosis (ALS) is frequently challenging, because motor neuron involvement is usually focal at disease onset and many syndromes mimic ALS. Neurological examination and needle EMG are important in the diagnosis of ALS, and patients with early-stage ALS usually undergo several EMG examinations before the diagnosis is confirmed. Ultrasonography has recently been used for the non-invasive assessment of neuromuscular disorders. This review discusses the recent advances in ultrasonography for ALS diagnosis. Ultrasonography could help detect lower motor neuron involvement by evaluating muscle volume, echo intensity, and fasciculations. Previous reports have documented the diagnostic values of all these parameters. In particular, fasciculations are characteristic features of ALS that can be easily and reliably visualized using ultrasonography. Moreover, the combined use of ultrasonography and EMG to detect fasciculations could substantially increase the diagnostic sensitivity of Awaji criteria for ALS. Attempts to utilize ultrasonography for ALS diagnosis have started only recently, and the technique used is yet to be standardized. However, ultrasonography has a major advantage over EMG in that it is non-invasive. Further studies are needed to understand the use of ultrasound as a novel non-invasive tool for ALS diagnosis. Source

Abe E.,University of Tokyo | Ono A.,University of Tokyo | Itoi T.,Chiba University | Yamasaki M.,Kumamoto University | Kawamura Y.,Kumamoto University
Philosophical Magazine Letters | Year: 2011

A series of structural polytypes formed in an Mg-1 at.%Zn-2 at.%Y alloy has been identified, which are reasonably viewed as long-period stacking derivatives of the hexagonal-close-packed Mg structure with alternate AB stacking of the close-packed atomic layers. Atomic-resolution Z-contrast imaging clearly revealed that the structures are long-period chemical-ordered as well as stacking-ordered; unique chemical order along the stacking direction occurs as being synchronized with a local faulted stacking of AB'C'A, where B' and C' layers are commonly enriched by Zn/Y atoms. © 2011 Taylor & Francis. Source

Nobe A.,Chiba University
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2011

We present a tropical geometric description of a piecewise linear map whose invariant curve is a concave polygon. In contrast to convex polygons, a concave one is not directly related to tropical geometry; nevertheless the description is given in terms of the addition formula of a tropical elliptic curve. We show that the map arises from a pair of tropical elliptic pencils, each member of which is the invariant curve of an ultradiscrete QRT map. © 2011 Elsevier B.V. All rights reserved. Source

Gridnev I.D.,Tokyo Institute of Technology | Gridnev I.D.,Tohoku University | Liu Y.,Tohoku University | Imamoto T.,Chiba University
ACS Catalysis | Year: 2014

The mechanism of asymmetric hydrogenation of five representative β-dehydroamino acids catalyzed by rhodium complexes of (R)-(tert- butylmethylphosphino)(di-tert-butylphosphino)methane (trichickenfootphos, TCFP) and (R,R)-1,2-bis(tert-butylmethylphosphino)benzene (BenzP*) was studied through a combination of extensive NMR experiments and state-of-the-art DFT computations in order to reveal the crucial factors governing the sense and order of enantioselectivity in this industrially important reaction. The binding mode of the substrate with a Rh(I) catalyst was found to be highly dependent on the nature of the rhodium complex and the substrate. Thus, no substrate binding was detected for [Rh((R,R)-BenzP*)S2]+SbF 6- (5) and (E)-3-acetylamino-2-butenoate (2a) even at 173 K. [Rh((R)-TCFP) S2]+BF4- (3) exhibited weak reversible binding with 2a in the temperature interval 173-253 K with the formation of complex 4a, whereas at ambient temperature, slow isomerization of 2a to (Z)-3-acetylamino-2-butenoate (2b) took place. The investigations with a total of 10 combinations of the catalysts and substrates demonstrated various binding modes that did not affect significantly the enantioselectivities observed in corresponding catalytic reactions and in low temperature hydrogenations of the catalyst-substrate complexes. The monohydride intermediate 10 formed quantitatively when the equilibrium mixture of 2a, 3, and 4a was hydrogenated at 173 K. Its molecular structure including relative stereochemistry was determined by NMR experiments. These results together with the stereochemichal outcome of the low-temperature hydrogenation (99.2% ee, R) and DFT calculations led to the reasonable reaction pathway of the asymmetric hydrogenation of 2a catalyzed by 3. The conceivable catalytic pathways were computed for five combinations of the BenzP*-Rh catalyst and prochiral β-dehydroamino acids 2a,b and 21-23. In most cases, it was found that the pathways involving the hydrogenation of Rh(I) square planar chelate complexes are usually higher in free energy than the pathways with the hydrogen activation prior to the chelate formation. Computed differences in the free energies of the transition states for the double bond coordination stage of the R and S pathways reasonably well reproduce the optical yields observed experimentally in the corresponding catalytic reactions and in the low temperature hydrogenation experiments. To explain extremely high ee's (>99% ee) in some of the hydrogenations, it is necessary to analyze in more detail the participation of the solvent in the enantiodetermining step. © 2013 American Chemical Society. Source

Neya S.,Chiba University | Yonetani T.,University of Pennsylvania | Kawaguchi A.T.,Tokai University
Artificial Organs | Year: 2014

The structure and reactivity of cobalt-replaced myoglobin (Mb) were investigated to explore its possible application as an artificial oxygen carrier. Ligand binding analysis with relaxation kinetics revealed that various ligands bind to Co(III) Mb, contrary to the earlier thoughts. The equilibration process, however, was so slow that it proceeded over 90min. These characteristic profiles of oxidized Co(III) Mb were ascribed to the electronic structure of Co(III) ion which is one electron larger than Fe(III) ion. The oxygen affinity of reduced Co(II) Mb was much smaller than that of Fe(II) Mb indicating that Co(II) Mb has excellent oxygen transport ability. The latter observation, together with the lack of carbon monoxide binding in Co(II) Mb, suggests utility of Co(II) Mb as Mb-based oxygen carriers. The present results on cobalt-substituted Mb are useful in designing myoglobin-based oxygen carriers. © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc. Source

Ito K.,Chiba University
IEEE Antennas and Propagation Society, AP-S International Symposium (Digest) | Year: 2015

At the Department of Medical System Engineering, Chiba University, we have Electromagnetics (EM) as one of the fundamental subjects for the undergraduate students. This paper describes some features and problems of EM education for non-EE students at the Department. © 2015 IEEE. Source

Nagase A.,Chiba University | Dunnett N.,University of Sheffield
Landscape and Urban Planning | Year: 2011

Choosing an appropriate substrate is one of the most important factors for green roofs because of their harsh growing environment. However, there have been few studies on the amount of organic matter necessary for sustainable plant growth in extensive green roofs. This study examined the relationship between percentage of organic matter in substrate and plant growth in extensive green roofs, particularly at establishment stage. Different percentages of organic matter (green waste compost: 0%, 10%, 25%, 50% by volume) were added and mixed well with a commercial green roof substrate (crushed brick base, containing less than 4% organic matter). Four species of plants (Allium schoenoprasum, Limonium latifolium, Melica ciliata and Nepeta×. faassenii) were grown in a greenhouse in trays containing substrates with these different percentages of organic matter. Two watering regimes were imposed: wet and dry (watering every 5 days or every 15 days). It was concluded that addition of 10% organic matter was optimal for these four species and the substrate used in this study because the plants showed stable growth regardless of the watering regime. In the wet regime, increased organic matter resulted in lush growth with may result in damage during drought. In the dry regime, increased organic matter did not result in increased growth. The response to higher organic matter content was different for different species, and species from a nitrogen-rich habitat tended to be encouraged by a high content. © 2011 Elsevier B.V. Source

Saito T.,Chiba University
Advances in Experimental Medicine and Biology | Year: 2012

The Notch pathway is essential for maintaining neural progenitor cells (NPCs) in the developing brain. Activation of the pathway is sufficient to maintain NPCs, whereas loss-of-function mutations in the critical components of the pathway cause precocious neuronal differentiation and NPC depletion. Hairy and Enhancer of split (Hes)-type transcription factors have long been thought to be the only Notch effectors for the maintenance of NPCs. Recently, a novel nuclear protein, Nepro, has been identified as another critical effector of Notch. The Notch pathway is bifurcated into Nepro and Hes-type proteins in the early development of the neocortex. The combination of Nepro and Hes-type proteins is necessary and sufficient for maintaining NPCs downstream of Notch. © 2012 Landes Bioscience and Springer Science+Business Media. Source

Matsumoto A.,Chiba University | Gow A.J.,Rutgers University
Nitric Oxide - Biology and Chemistry | Year: 2011

The distinctive function of nitric oxide (NO) in biology is to transmit cellular signals through membranes and regulate cellular functions in adjacent cells. NO conveys signals as a second messenger from a cell where NO is generated to contiguous cells in two ways; one is as gaseous molecule by free diffusion resulting in an activation of soluble guanylate cyclase (NO/cGMP pathway), and another form is by binding with a molecule such as cysteine or protein thiol through S-nitrosylation (SNO pathway). Both pathways transmit much of the biological influence of NO from cell where other messenger molecules but NO are confined, through the plasma membrane to the adjacent cells. Since SNO pathway cannot utilize free-diffusion mechanism to get through the membrane as the molecular size is significantly larger than NO molecule, it utilizes amino acid transporter to convey signals as a form of S-nitrosylated cysteine (CysNO). Although S-nitrosylated glutathione (GSNO) is the molecule which act as a determinant of the total S-nitrosothiol level in cell, transnitrosylation reaction from GSNO to CysNO is an initial requirement to pass through signal through the membrane. Thus, multiplexed combination of these steps and the regulatory factors involved in this system conform and modify the outcome from stimulus-response coupling via the SNO pathway. © 2010 Published by Elsevier Inc. Source

Ly M.,Rensselaer Polytechnic Institute | Leach F.E.,University of Georgia | Laremore T.N.,Rensselaer Polytechnic Institute | Toida T.,Chiba University | And 2 more authors.
Nature Chemical Biology | Year: 2011

Proteoglycans are complex glycoconjugates that regulate critical biological pathways in all higher organisms. Bikunin, the simplest proteoglycan, with a single glycosaminoglycan chain, is a serine protease inhibitor used to treat acute pancreatitis. Unlike nucleic acids and proteins, whose synthesis is template driven, Golgi-synthesized glycosaminoglycans are not believed to have predictable or deterministic sequences. Bikunin peptidoglycosaminoglycans were prepared and fractionated to obtain a collection of size-similar and charge-similar chains. Fourier transform mass spectral analysis identified a small number of parent molecular ions corresponding to monocompositional peptidoglycosaminoglycans. Fragmentation using collision-induced dissociation unexpectedly afforded a single sequence for each monocompositional parent ion, unequivocally demonstrating the presence of a defined sequence. The biosynthetic pathway common to all proteoglycans suggests that even more structurally complex proteoglycans, such as heparan sulfate, may have defined sequences, requiring a readjustment in the understanding of information storage in complex glycans. © 2011 Nature America, Inc. All rights reserved. Source

Nakada T.-A.,University of British Columbia | Nakada T.-A.,Chiba University | Russell J.A.,University of British Columbia | Boyd J.H.,University of British Columbia | And 2 more authors.
Critical Care Medicine | Year: 2015

Objectives: Mortality from septic shock is highly heritable. The identification of causal genetic factors is insufficient. To discover key contributors, we first identified nonsynonymous single-nucleotide polymorphisms in conserved genomic regions that are predicted to have significant effects on protein function. We then test the hypothesis that these nonsynonymous single-nucleotide polymorphisms across the genome alter clinical outcome of septic shock. Design: Genetic-association study plus in vitro experiment using primary cells plus in silico analysis using genomic DNA and protein database. Setting: Twenty-seven ICUs at academic teaching centers in Canada, Australia, and the United States. Patients: Patients with septic shock of European ancestry (n = 520). Interventions: Patients with septic shock were genotyped for 843 nonsynonymous single-nucleotide polymorphisms in conserved regions of the genome and are predicted to have damaging effects from the protein sequence. Measurements and Main Results: The primary outcome variable was 28-day mortality. Secondary outcome variables were organ dysfunction. Productions of adhesion molecules including interleukin- 8, growth-regulated oncogene-α, monocyte chemoattractant protein-1, and monocyte chemoattractant protein-3 were measured in human umbilical vein endothelial cells after SVEP1 gene silencing by RNA interference. Patients with septic shock having the SVEP1 C allele of nonsynonymous single-nucleotide polymorphism, SVEP1 c.2080A>C (p. Gln581His, rs10817033), had a significant increase in the hazard of death over the 28 days (hazard ratio, 1.72; 95% CI, 1.31-2.26; p = 9.7 × 10-5) and increased organ dysfunction and needed more organ support (p < 0.05). Silencing SVEP1 significantly increased interleukin-8, growth-regulated oncogene-α, monocyte chemoattractant protein-1, monocyte chemoattractant protein-3 production in human umbilical vein endothelial cells under lipopolysaccharide stimulation (p < 0.01). Conclusions: C allele of SVEP1 c.2080A>C (p. Gln581His) single-nucleotide polymorphism, a non-synonymous singlenucleotide polymorphism in conserved regions and predicted to have damaging effects on protein structure, was associated with increased 28-day mortality and organ dysfunction of septic shock. SVEP1 appears to regulate molecules of the leukocyte adhesion pathway. Source

Li W.,East China University of Science and Technology | Shen J.,East China University of Science and Technology | Liu G.,East China University of Science and Technology | Tang Y.,East China University of Science and Technology | Hoshino T.,Chiba University
Proteins: Structure, Function and Bioinformatics | Year: 2011

The kinetic analysis of coumarin oxidation by CYP2A6 suggested that substrate binding and release occurred in the multiple steps and such events proceeded rapidly. However, the crystal structure of the CYP2A6-coumarin complex reveals that no obvious channel is open enough to allow coumarin to pass through. Thus, an intriguing and important question arises: how coumarin enters and exits the active site, which is deeply buried at the center of CYP2A6 fold. In this study, geometric analysis of the potential openings was first performed on all the available crystal structures of CYP2A6. And then, random acceleration molecular dynamics simulations were used to explore the possible substrate egress channels in CYP2A6. Two channels were most frequently observed. Afterwards, steered molecular dynamics simulations were performed and potentials of mean force were constructed to compare the preference of the two channels serving as the substrate egress channel. The results showed that channel 2c, which is located between helices I and G and the helix B'-C region, was the most likely channel for coumarin egress. The opening of channel 2c was characterized by a rotation of Phe111 together with a bending of helix B'. Our findings will not only be helpful for understanding the unbinding mechanism of coumarin and for identifying structural determinants related to the biological function of CYP2A6, but also provide further insight into the channel selectivity of P450s. Proteins 2010. © 2010 Wiley-Liss, Inc. Source

Ahn C.-J.,Chiba University
Recent Researches in Circuits, Systems, Control and Signals - Proceedings of the 2nd International Conference on Circuits, Systems, Control, Signals, CSCS'11 | Year: 2011

The electrical power generated by RF energy harvesting techniques is small, depending on techniques it is enough to drive low power consumption devices. Therefore, it is possible to increase the battery life and to reduce the environmental pollution. In this paper, we focus on the RF energy harvesting and design the rectenna with a 4×4 patch antenna of 2.13 GHz for low power mobile devices. The rectenna element is a microstrip patch antenna with PTFT board of 10 dielectric constant and 1.6 mm thick that has a gain of 5.8dBi. A step-up converter is adopted the Texas Instruments TPS61220. The step-up converter is operated with load at 0.7V to 5.5V. If the output current is 1.7mA, the conversion efficiency shows 80.9%. From the evaluated results of RF energy harvesting system, the low power mobile devices such as Zigbee when we set the distance of 12m can be operated. Source

Lee J.,Chiba University
Nihon eiseigaku zasshi. Japanese journal of hygiene | Year: 2011

To provide scientific evidence of the health benefits of forest therapy in terms of physiological indices. Design: Within-group comparison made by conducting field experiments. Participants: Forty-eight young male adults. Field experiments were conducted at four local sites in Japan. At each site, 12 adults participated in a three-day experiment. To compare physiological reactions between two environmental stimuli, experiments were conducted in forest and urban environments. The participants were randomly assigned to visit either the forest or an urban setting and were instructed to view the landscape in a seated position. The physiological reactions of each participant were recorded before, during, and after viewing the stimuli, and the differences in physiological indices were compared between the two groups. Physiological data revealed that participants demonstrated significantly different reactions in the forest and urban environments. Analysis of heart rate revealed that participants showed a significantly higher ln(HF) and a lower ln(LF/HF) in the forest environment than in the urban environment. Systolic and diastolic blood pressures, pulse rate, and salivary cortisol concentration significantly decreased in the forest environment compared with the urban environment. Subjective evaluation data were generally in accordance with physiological reactions, showing significantly higher scores for "comfortable, natural, soothed, and refreshed feelings" in the forest environment than in the urban environment. This study provided very clear scientific evidence of the physiological effects of forest therapy. Our data indicate that forest therapy can decrease stress and facilitate physiological relaxation. Source

Yamori W.,Chiba University | Hikosaka K.,Tohoku University | Hikosaka K.,Japan Science and Technology Agency | Way D.A.,University of Western Ontario | Way D.A.,Duke University
Photosynthesis Research | Year: 2014

Most plants show considerable capacity to adjust their photosynthetic characteristics to their growth temperatures (temperature acclimation). The most typical case is a shift in the optimum temperature for photosynthesis, which can maximize the photosynthetic rate at the growth temperature. These plastic adjustments can allow plants to photosynthesize more efficiently at their new growth temperatures. In this review article, we summarize the basic differences in photosynthetic reactions in C3, C4, and CAM plants. We review the current understanding of the temperature responses of C3, C4, and CAM photosynthesis, and then discuss the underlying physiological and biochemical mechanisms for temperature acclimation of photosynthesis in each photosynthetic type. Finally, we use the published data to evaluate the extent of photosynthetic temperature acclimation in higher plants, and analyze which plant groups (i.e., photosynthetic types and functional types) have a greater inherent ability for photosynthetic acclimation to temperature than others, since there have been reported interspecific variations in this ability. We found that the inherent ability for temperature acclimation of photosynthesis was different: (1) among C3, C 4, and CAM species; and (2) among functional types within C 3 plants. C3 plants generally had a greater ability for temperature acclimation of photosynthesis across a broad temperature range, CAM plants acclimated day and night photosynthetic process differentially to temperature, and C4 plants was adapted to warm environments. Moreover, within C3 species, evergreen woody plants and perennial herbaceous plants showed greater temperature homeostasis of photosynthesis (i.e., the photosynthetic rate at high-growth temperature divided by that at low-growth temperature was close to 1.0) than deciduous woody plants and annual herbaceous plants, indicating that photosynthetic acclimation would be particularly important in perennial, long-lived species that would experience a rise in growing season temperatures over their lifespan. Interestingly, across growth temperatures, the extent of temperature homeostasis of photosynthesis was maintained irrespective of the extent of the change in the optimum temperature for photosynthesis (T opt), indicating that some plants achieve greater photosynthesis at the growth temperature by shifting T opt, whereas others can also achieve greater photosynthesis at the growth temperature by changing the shape of the photosynthesis-temperature curve without shifting T opt. It is considered that these differences in the inherent stability of temperature acclimation of photosynthesis would be reflected by differences in the limiting steps of photosynthetic rate. © 2013 Springer Science+Business Media Dordrecht. Source

Yamada T.,Chiba University
Advances in Intelligent Systems and Computing | Year: 2016

Information and Communication Technologies (ICTs) have triggered the innovations of pedagogies and learning methods in all levels of education. In addition to distance education, e-Learning is expected to improve classroom teaching through educational tools and digital content in various blended approaches; Mobile devices and SNS showed the new content distribution and knowledge sharing in learner communities; MOOCs (Massive Open Online Courses) expanded the opportunities of quality education on a global level. This paper discusses the Japanese practices in which MOOCs acted as catalysts implementing component technologies and development strategies for e-Learning. © Springer International Publishing Switzerland 2016. Source

The purpose of the present study was to compare sinusoidal versus constant lower body negative pressure (LBNP) with reference to very mild whole-body heating. Sinusoidal LBNP has a periodic load component (PLC) and a constant load component (CLC) of orthostatic stress, whereas constant LBNP has only a CLC. We tested two sinusoidal patterns (30-s and 180-s periods with 25 mmHg amplitude) of LBNP and a constant LBNP with -25 mmHg in 12 adult male subjects. Although the CLC of all three LBNP conditions were configured with -25 mmHg, the mean arterial pressure (MAP) results showed a significantly large decrease from baseline in the 30-s period condition (P <0.01). In contrast, the other cardiovascular indices (heart rate (HR), stroke volume (SV), cardiac output (CO), basal thoracic impedance (Z(0)), total peripheral resistance (TPR), the natural logarithmic of the HF component (lnHF), and LF/HF (ln(LF/HF))) of heart rate variability (HRV) showed relatively small variations from baseline in the 30-s period condition (P <0.01). The result of the gain and phase of transfer function at the sinusoidal period of LBNP showed that the very mild whole-body heating augmented the orthostatic responses. These results revealed that the effect of the CLC of LBNP on cardiovascular adjustability was attenuated by the addition of the PLC to LBNP. Based on the results of suppressed HRV response from baseline in the 30-s period condition, we suggest that the attenuation may be caused by the suppression of the vagal responsiveness to LBNP. Source

Ashida H.,Tokyo Medical University | Nakano H.,Juntendo University | Sasakawa C.,Tokyo Medical University | Sasakawa C.,Nippon Institute for Biological Science | Sasakawa C.,Chiba University
PLoS Pathogens | Year: 2013

NF-κB plays a central role in modulating innate immune responses to bacterial infections. Therefore, many bacterial pathogens deploy multiple mechanisms to counteract NF-κB activation. The invasion of and subsequent replication of Shigella within epithelial cells is recognized by various pathogen recognition receptors as pathogen-associated molecular patterns. These receptors trigger innate defense mechanisms via the activation of the NF-κB signaling pathway. Here, we show the inhibition of the NF-κB activation by the delivery of the IpaH E3 ubiquitin ligase family member IpaH0722 using Shigella's type III secretion system. IpaH0722 dampens the acute inflammatory response by preferentially inhibiting the PKC-mediated activation of NF-κB by ubiquitinating TRAF2, a molecule downstream of PKC, and by promoting its proteasome-dependent degradation. © 2013 Ashida et al. Source

Furusawa Y.,Keio University | Furusawa Y.,Tokyo Medical University | Obata Y.,Tokyo Medical University | Obata Y.,Chiba University | And 2 more authors.
Seminars in Immunopathology | Year: 2015

Commensal microbiota shapes the intestinal immune system by regulating T helper(TH)cell lineage differentiation. For example, Bacteroides fragilis colonization not only optimizes the systemic TH1/TH2 balance, but also can induce regulatory T (Treg) cell differentiation in the gut. In addition, segmented filamentous bacteria (SFB) facilitate the development of TH17 cells in the small intestine. The 17 strains within clusters IV, XIVa, and XVIII of Clostridiales found in human feces can also induce the differentiation and expansion of Treg cells in the colon. Thus, the regulation of THcell differentiation by commensal bacteria is evident; however, the molecular mechanisms underlying these processes remain uncertain. Recent studies have demonstrated that bacterial components, as well as their metabolites, play a central role in regulating THcell development. Furthermore, these metabolites can elicit changes in histone posttranslational modification to modify the expression of critical regulators of T cell fate. In this review, we discuss the mechanisms and biological significance of microbiota-dependent THdifferentiation. © 2014, Springer-Verlag Berlin Heidelberg. Source

Hayati M.,Razi University | Lotfi A.,Razi University | Kazimierczuk M.K.,Wright State University | Sekiya H.,Chiba University
IEEE Transactions on Power Electronics | Year: 2013

This paper presents analytical expressions for the class-E power amplifier with a shunt inductor for satisfying the subnominal condition and 50% duty ratio. The subnominal condition means that only the zero-current switching condition (ZCS) is achieved, though the nominal conditions mean that both the ZCS and zero-current derivative switching (ZCDS) are satisfied. The design values for achieving the subnominal condition are expressed as a function of the phase shift between the input and output voltages. The class-E amplifier with subnominal condition increases one design degree of freedom compared with that with the nominal conditions. Because of the increase in the design degree of freedom, one more relationship can be specified as a design specification. It is shown analytically that the dc-supply voltage and the current are always proportional to the amplitude of the output voltage and the current as a function of the phase shift. Additionally, the output power capability is affected by the phase shift, and the peak switch voltage has influence on the phase shift as well. This paper gives a circuit design example based on our proposed design expression by specifying the peak switch voltage instead of the ZCDS condition. The measurement and PSpice simulation results agree with the analytical expressions quantitatively, which show the validity of our analytical expressions. © 1986-2012 IEEE. Source

Uncini A.,University of Chieti Pescara | Kuwabara S.,Chiba University
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2015

Peripheral nerve diseases are traditionally classified as demyelinating or axonal. It has been recently proposed that microstructural changes restricted to the nodal/paranodal region may be the key to understanding the pathophysiology of antiganglioside antibody mediated neuropathies. We reviewed neuropathies with different aetiologies (dysimmune, inflammatory, ischaemic, nutritional, toxic) in which evidence from nerve conductions, excitability studies, pathology and animal models, indicate the involvement of the nodal region in the pathogenesis. For these neuropathies, the classification in demyelinating and axonal is inadequate or even misleading, we therefore propose a new category of nodopathy that has the following features: (1) it is characterised by a pathophysiological continuum from transitory nerve conduction block to axonal degeneration; (2) the conduction block may be due to paranodal myelin detachment, node lengthening, dysfunction or disruption of Na+ channels, altered homeostasis of water and ions, or abnormal polarisation of the axolemma; (3) the conduction block may be promptly reversible without development of excessive temporal dispersion; (4) axonal degeneration, depending on the specific disorder and its severity, eventually follows the conduction block. The term nodopathy focuses to the site of primary nerve injury, avoids confusion with segmental demyelinating neuropathies and circumvents the apparent paradox that something axonal may be reversible and have a good prognosis. © 2015, BMJ Publishing Group. All rights reserved. Source

Nakanishi M.,Chiba University | Hashimoto J.,Nagasaki University
Marine Geophysical Research | Year: 2011

Data from three bathymetric surveys by R/V Kairei using a 12-kHz multibeam echosounder and differential GPS were used to create an improved topographic model of the Challenger Deep in the southwestern part of the Mariana Trench, which is known as the deepest seafloor in the world. The strike of most of the elongated structures related to plate bending accompanied by subduction of the Pacific plate is N70°E and is not parallel to the trench axis. The bending-related structures were formed by reactivation of seafloor spreading fabric. Challenger Deep consists of three en echelon depressions along the trench axis, each of which is 6-10 km long, about 2 km wide, and deeper than 10,850 m. The eastern depression is the deepest, with a depth of 10,920 ± 5 m. © 2011 Springer Science+Business Media B.V. Source

Jiao Y.,Tokyo Institute of Technology | Yamada S.,Tokyo Institute of Technology | Kishiki S.,Tokyo Institute of Technology | Shimada Y.,Chiba University
Earthquake Engineering and Structural Dynamics | Year: 2011

The energy dissipation capacity of a structure is a very important index that indicates the structural performance in energy-based seismic design. This index depends greatly on the structural components that form the whole system. Owing to the wide use of the strong-column weak-beam strength hierarchy where steel beams dissipate the majority of earthquake input energy to the structures, it is necessary to evaluate the energy dissipation capacity of the beams. Under cyclic loadings such as seismic effects, the damage of the beams accumulates. Therefore, loading history is known to be the most pivotal factor influencing the deformation capacity and energy dissipation capacity of the beams. Seismic loadings with significantly different characteristics are applied to structural beams during different types of earthquakes and there is no unique appropriate loading protocol that can represent all types of seismic loadings. This paper focuses on the effects of various loading histories on the deformation capacity and energy dissipation capacity of the beams. Cyclic loading tests of steel beams were performed. In addition, some experimental results from published tests were also collected to form a database. This database was used to evaluate the energy dissipation capacity of steel beams suffering from ductile fracture under various loading histories. © 2011 John Wiley & Sons, Ltd. Source

Yamamoto M.K.,Chiba University | Ueno K.,University of Tsukuba | Nakamura K.,Nagoya University
Journal of the Meteorological Society of Japan | Year: 2011

Rain gauge data for the period of 1998-2004 from the Syangboche Automated Weather Station (S-AWS) site in the Nepal Himalayas were compared with multi-satellite precipitation products for the period of 2003-2005, employing several retrieval algorithms: the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA), the Climate Prediction Center (CPC) morphing algorithm (CMORPH), the Precipitation Estimation from Remote Sensing Information using an artificial neural network (PERSIANN), and the Global Satellite Mapping of Precipitation (GSMaP). All the products, except GSMaP, showed an increase in precipitation during the summer monsoon, in agreement with S-AWS. However, PERSIANN showed large differences with the observed values in winter and CMORPH had a tendency to overestimate precipitation in the pre- and post-monsoon seasons relative to S-AWS/TMPA. Summer monsoon precipitation showed an increase in the evening and mid-night in all products except GSMaP, but the local-time peak in PERSIANN lagged compared to that of S-AWS by several hours, and the peak in other products was ahead of that in S-AWS by several hours. All products except for PERSIANN showed an increase in precipitation during the morning. The differences among the products may reflect microwave signatures from convection, the sun-synchronous satellite orbit, and infrared-merging processes. A verification of rain detection by GSMaP revealed good scores over global land areas except for the Tibetan Plateau (including the present study area) due to insufficient resolution for rain/no-rain classification. The peak local-time distribution of precipitation showed a relationship with the topography in the order of precipitation radar (strongest relationship), microwave radiometer, and infrared products. © 2011, Meteorological Society of Japan. Source

Matsuda S.,Chiba University
Progress in neuro-psychopharmacology & biological psychiatry | Year: 2010

Several lines of evidence suggest that the N-methyl-D-aspartate (NMDA) receptor plays a significant role in fear conditioning and extinction. However, our knowledge of the role of D-serine, an endogenous ligand for the glycine site of the NMDA receptor, in fear extinction is quite limited compared to that of D-cycloserine, an exogenous partial agonist for the same site. In the current study, we examined the effects of D-serine on fear extinction and phosphorylation of extracellular signal-regulated kinase (ERK) in the hippocampus, basolateral amygdala (BLA), and medial prefrontal cortex (mPFC) during the process of fear extinction. Systemic administrations of D-serine (2.7 g/kg, i.p.) with or without the ERK inhibitor SL327 (30 mg/kg, i.p.) to C57BL/6J mice were performed before fear extinction in a cued fear conditioning and extinction paradigm. Cytosolic and nuclear ERK 1/2 phosphorylation in the hippocampus, BLA, and mPFC were measured 1h after extinction (E1h), 24h after extinction (E24h), and 1h after recall (R1h) by Western blotting. We found that D-serine enhanced the extinction of fear memory, and the effects of D-serine were reduced by the ERK phosphorylation inhibitor SL327. The Western blot analyses showed that D-serine significantly increased cytosolic ERK 2 phosphorylation at E1h in the hippocampus and cytosolic ERK 1/2 phosphorylation at R1h in the BLA. The present study suggested that D-serine might enhance fear extinction through NMDA receptor-induced ERK signaling in mice, and that D-serine has potential clinical importance for the treatment of anxiety disorders. Copyright (c) 2010 Elsevier Inc. All rights reserved. Source

Ohya H.,Chiba University | Shiokawa K.,Nagoya University | Miyoshi Y.,Nagoya University
Journal of Geophysical Research: Space Physics | Year: 2011

We investigated, for the first time, long-term (1976-2010) variations in reflection heights of tweek atmospherics based on very low frequency (VLF) observations at Kagoshima, Japan. The results revealed the effects of the solar cycle on the nighttime lower ionosphere at low to middle latitudes. The tweek reflection heights on geomagnetically quiet days were analyzed every month over three solar cycles by using an automated spectral fitting procedure to estimate the cutoff frequency. The average and standard deviation of the reflection height were 95.9 km and ±3.1 km, respectively. Typical periods of time variation for the reflection height were 13.3, 3.2, 1.3, 1.0, 0.6, and 0.5 years. The variations in tweek reflection heights did not show simple anticorrelation with solar activity. The correlation coefficient between tweek reflection height and sunspot number was 0.03 throughout the three solar cycles. Hilbert-Huang transform analysis successfully indicated the presence of 0.5-1.5 year and ∼10 year variations as intrinsic mode functions (IMF). The decomposed IMF with the ∼10 year variation had a positive correlation with sunspot numbers and a negative correlation with galactic cosmic rays (GCRs). We hypothesize that these variations in tweek reflection heights could be caused by coupling of several ionization effects at the D and lower E regions, effects such as geocorona, GCRs, particle precipitation, and variations in neutral density in the lower thermosphere. Among these processes, the geocorona and particle precipitation could show negative correlation, while the GCRs and neutral density could show positive correlation with solar activities. Copyright 2011 by the American Geophysical Union. Source

Lee S.,Chiba University
Journal of physiological anthropology | Year: 2012

Recently, mist saunas have been used in the home as a new bathing style in Japan. However, there are still few reports on the effects of bathing methods on recovery from muscle fatigue. Furthermore, the effect of mist sauna bathing on human physiological function has not yet been revealed. Therefore, we measured the physiological effects of bathing methods including the mist sauna on recovery from muscle fatigue. The bathing methods studied included four conditions: full immersion bath, shower, mist sauna, and no bathing as a control. Ten men participated in this study. The participants completed four consecutive sessions: a 30-min rest period, a 10-min all out elbow flexion task period, a 10-min bathing period, and a 10-min recovery period. We evaluated the mean power frequency (MNF) of the electromyogram (EMG), rectal temperature (Tre), skin temperature (Tsk), skin blood flow (SBF), concentration of oxygenated hemoglobin (O2Hb), and subjective evaluation. We found that the MNF under the full immersion bath condition was significantly higher than those under the other conditions. Furthermore, Tre, SBF, and O2Hb under the full immersion bath condition were significantly higher than under the other conditions. Following the results for the full immersion bath condition, the SBF and O2Hb of the mist sauna condition were significantly higher than those for the shower and no bathing conditions. These results suggest that full immersion bath and mist sauna are effective in facilitating recovery from muscle fatigue. Source

Accumulated evidence shows an association between Epstein-Barr viral (EBV) infection and multiple sclerosis (MS). In particular, EBV infections before the onset of MS, particularly in childhood, is associated with the pathogenesis of MS. Meanwhile, the association between neuromyelitis optica (NMO) and infectious agents has been reported, but is currently unclear. Recently we studied the association between NMO and EBV and compared between MS and EBV. The results showed that MS is associated with past infections of EBV as the results of previous studies. In contrast, NMO is associated with the reactivation of EBV. Source

Yamaguchi M.,Chiba University | Kopecka M.,Masaryk University
Journal of Electron Microscopy | Year: 2010

Phenotypes of the two temperature-sensitive actin mutants of Saccharomyces cerevisiae act1-1 and act1-2 at permissive, restrictive and semi-restrictive temperatures were studied by freeze fracture and thin section electron microscopy, and fluorescent microscopy. In contrast to secretory mutants where accumulations of either secretory vesicles, Golgi apparatus, or endoplasmic reticulum were reported, act1-1 and act1-2 mutants revealed accumulation of all the three components, even at permissive temperature. However, more distinct accumulation of secretory organelles was evident during cultivation at the sub-restrictive temperature of 30°C. At the restrictive temperature of 37°C, many cells died, and their empty cell walls remained. Some of the few living cells showed features of apoptosis. From the present study, actin cables are concluded to be necessary for (i) correct spatial positioning and orientation of secretary pathway to the bud and septum, and (ii) vectorial movement of vesicles of the secretory pathway along the actin cables to the bud and septum. © 2009 The Author. Source

Schmaus S.,Karlsruhe Institute of Technology | Bagrets A.,Karlsruhe Institute of Technology | Nahas Y.,Karlsruhe Institute of Technology | Yamada T.K.,Karlsruhe Institute of Technology | And 6 more authors.
Nature Nanotechnology | Year: 2011

Magnetoresistance is a change in the resistance of a material system caused by an applied magnetic field. Giant magnetoresistance occurs in structures containing ferromagnetic contacts separated by a metallic non-magnetic spacer, and is now the basis of read heads for hard drives and for new forms of random access memory. Using an insulator (for example, a molecular thin film) rather than a metal as the spacer gives rise to tunnelling magnetoresistance, which typically produces a larger change in resistance for a given magnetic field strength, but also yields higher resistances, which are a disadvantage for real device operation. Here, we demonstrate giant magnetoresistance across a single, non-magnetic hydrogen phthalocyanine molecule contacted by the ferromagnetic tip of a scanning tunnelling microscope. We measure the magnetoresistance to be 60% and the conductance to be 0.26G0, where G0 is the quantum of conductance. Theoretical analysis identifies spin-dependent hybridization of molecular and electrode orbitals as the cause of the large magnetoresistance. © 2011 Macmillan Publishers Limited. All rights reserved. Source

Yamamura S.,Japan National Institute of Environmental Studies | Amachi S.,Chiba University
Journal of Bioscience and Bioengineering | Year: 2014

Arsenic (As) contamination of drinking water and soils poses a threat to a large number of people worldwide, especially in Southeast Asia. The predominant forms of As in soils and aquifers are inorganic arsenate [As(V)] and arsenite [As(III)], with the latter being more mobile and toxic. Thus, redox transformations of As are of great importance to predict its fate in the environment, as well as to achieve remediation of As-contaminated water and soils. Although As has been recognized as a toxic element, a wide variety of microorganisms, mainly bacteria, can use it as an electron donor for autotrophic growth or as an electron acceptor for anaerobic respiration. In addition, As detoxification systems in which As is oxidized to the less toxic form or reduced for subsequent excretion are distributed widely in microorganisms. This review describes current development of physiology, biochemistry, and genomics of arsenic-transforming bacteria. Potential application of such bacteria to removal of As from soils and water is also highlighted. © 2013 The Society for Biotechnology, Japan. Source

Kimura E.,Chiba University | Young R.S.L.,Texas Tech University Health Sciences Center
Vision Research | Year: 2010

We show that irradiance-coding alone cannot explain the sustained pupillary constrictions evoked by chromatic and luminance variations in a stimulus. For example, stimulus modulations that decremented the contrasts in L- and M-cones as well as rods and melanopsin photoreceptors produced sustained constrictions rather than the predicted dilations. Although the sustained responses are unidirectional, we confirm that they are at least partially mediated by an L- and M-cone opponent interaction. We discuss the implications of sustained unidirectional chromatic responses in view of the function of the pupil to improve the clarity of vision. © 2010 Elsevier Ltd. All rights reserved. Source

Sekiguchi T.,Suntory Institute for Bioorganic Research | Ogasawara M.,Chiba University | Satake H.,Suntory Institute for Bioorganic Research
Journal of Endocrinology | Year: 2012

Cholecystokinin (CCK) and gastrin are vertebrate brain-gut peptides featured by a sulfated tyrosine residue and a C-terminally amidated tetrapeptide consensus sequence. Cionin, identified in the ascidian, Ciona intestinalis, the closest species to vertebrates, harbors two sulfated tyrosines and the CCK/gastrin consensus tetrapeptide sequence. While a putative cionin receptor, cior, was cloned, the ligand-receptor relationship between cionin and CioR remains unidentified. Here, we identify two cionin receptors, CioR1 and CioR2, which are the aforementioned putative cionin receptor and its novel paralog respectively. Phylogenetic analysis revealed that CioRs are homologous to vertebrate CCK receptors (CCKRs) and diverged from a common ancestor in the Ciona-specific lineage. Cionin activates intracellular calcium mobilization in cultured cells expressing CioR1 or CioR2. Monosulfated and nonsulfated cionin exhibited less potent or no activity, indicating that CioRs possess pharmacological features similar to the vertebrate CCK-specific receptor CCK1R, rather than its subtype CCK2R, given that a sulfated tyrosine in CCK is required for binding to CCK1R, but not to CCK2R. Collectively, the present data reveal that CioRs share a common ancestor with vertebrate CCKRs and indicate that CCK and CCK1R form the ancestral ligand-receptor pair in the vertebrate CCK/gastrin system. Cionin is expressed in the neural complex, digestive organs, oral siphon and atrial siphons, whereas the expression of ciors was detected mainly in these tissues and the ovary. Furthermore, cioninergic neurons innervate both of the siphons. These results suggest that cionin is involved in the regulation of siphonal functions. © 2012 Society for Endocrinology. Source

Nagai T.,Chiba University | Komuro I.,Osaka University
American Journal of Physiology - Heart and Circulatory Physiology | Year: 2012

Despite significant advances in pharmacological and clinical treatment, heart failure (HF) remains a leading cause of morbidity and mortality worldwide. Many new therapeutic strategies, including cell transplantation, gene delivery, and cytokines or other small molecules, have been explored to treat HF. Recent advancement of our understanding of the molecules that regulate cardiac function uncover many of the therapeutic key molecules to treat HF. Furthermore, a theory of paracrine mechanism, which underlies the beneficial effects of cell therapy, leads us to search novel target molecules for genetic or pharmacological strategy. Gene therapy means delivery of genetic materials into cells to achieve therapeutic effects. Recently, gene transfer technology in the cardiovascular system has been improved and several therapeutic target genes have been started to examine in clinical research, and some of the promising results have been emerged. Among the various bioactive reagents, cytokines such as granulocyte colony-stimulating factor and erythropoietin have been well examined, and a number of clinical trials for acute myocardial infarction and chronic HF have been conducted. Although further research is needed in both preclinical and clinical areas in terms of molecular mechanisms, safety, and efficiency, both gene and cytokine therapy have a great possibility to open the new era of the treatment of HF. © 2012 the American Physiological Society. Source

Engstrom A.,Karolinska Institutet | Michaelsson K.,Uppsala University | Suwazono Y.,Chiba University | Wolk A.,Karolinska Institutet | And 2 more authors.
Journal of Bone and Mineral Research | Year: 2011

All people are exposed to cadmium (Cd) via food; smokers are additionally exposed. High Cd exposure is associated with severe bone damage, but the public health impact in relation to osteoporosis and fractures at low environmental exposure remains to be clarified. Within the population-based Swedish Mammography Cohort, we assessed urinary Cd [U-Cd, μg/g of creatinine (cr)] as a marker of lifetime exposure and bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) among 2688 women. Register-based information on fractures was retrieved from 1997 to 2009. Associations were evaluated by multivariable regression analyses. In linear regression, U-Cd was inversely associated with BMD at the total body (p<.001), femoral neck (p=.025), total hip (p=.004), lumbar spine (p=.088), and volumetric femoral neck (p=.013). In comparison with women with U-Cd<0.50μg/g of cr, those with U-Cd ≥ 0.75μg/g of cr had odds ratios (ORs) of 2.45 [95% confidence interval (CI) 1.51-3.97] and 1.97 (95% CI 1.24-3.14) for osteoporosis at the femoral neck and lumbar spine, respectively. Among never-smokers, the corresponding ORs were 3.47 (95% CI 1.46-8.23) and 3.26 (95% CI 1.44-7.38). For any first fracture (n=395), the OR was 1.16 (95% CI 0.89-1.50) comparing U-Cd ≥ 0.50μg/g of cr with lower levels. Among never-smokers, the ORs (95% CIs) were 2.03 (1.33-3.09) for any first fracture, 2.06 (1.28-3.32) for first osteoporotic fracture, 2.18 (1.20-3.94) for first distal forearm fracture, and 1.89 (1.25-2.85) for multiple incident fractures. U-Cd at low environmental exposure from food in a general population of women showed modest but significant association with both BMD and fractures, especially in never-smokers, indicating a larger concern than previously known. © 2011 American Society for Bone and Mineral Research. Copyright © 2011 American Society for Bone and Mineral Research. Source

Purpose: Effective adjuvant chemotherapy (Adj.C) for completely resected non-small cell lung cancer (NSCLC) was recently established. However, there may be some unresolved adverse effects, as have been observed in early stage populations or long-term survivors after other types of Adj.C. The substantial risk in such patients was examined by a mathematical method. Methods: Variables X and Y were defined by two outcomes of Adj.C: X = the ability to eliminate micro-metastasis and Y = the development of effects that threaten life. Then, the following formula was generated: Survival benefit = (death rate) X - (death rate) X Y - (survival rate) Y. We then solved for X and Y and verified our findings using reported data from clinical trials. Results: By solving two simultaneous equations for the formula applied to the data for stage (1) IA and (2) IIIA in the LACE study (J Clin Oncol 26:5043-5051, 2008), X and Y were 2.6 and 1.9, respectively. When these values were applied in the formula for stage IB patients in the same study, the theoretical (-2.3 %) and reported values (2.5 %) were close. When these were applied for stage IB-IIIA patients in the IALT study (N Engl J Med 350:351-360, 2004), the theoretical (5.0 %) and reported values (4.1 %) were also similar. Conclusion: Assuming a substantial risk provides an explanation for the stage-dependent outcomes of Adj.C for completely resected NSCLC. © 2013 Springer Japan. Source

Oi N.,Tokyo Womens Medical University | Ohi K.,Chiba University
International Journal of Cosmetic Science | Year: 2012

We conducted a survey to elucidate the influence with menopause symptoms and the impact of not only smoking but also using make-up among for Japanese women, included ages above and below the menopausal generation. The subjects of this study were 335 Japanese women from 35 to 59 years of age who were examined for the first time in the specialized women's outpatient clinic of our institution from July 2010 to June 2011 for 1 year period. We used the items of the Menopause-Specific Quality of Life Questionnaire. Similarly, we analysed the scores in relation to menopausal symptoms and whether the subject smoked, whether the subject used make-up depend on women (including foundation, lip rouge, brush one's eyebrows), how frequently she used make-up. The JMP version 9.0 software program was used to statistically analyse the score data. Significant associations were observed in psychosocial (P = 0.0196), tended to be more severe in women before menopause and after climacteric. Furthermore, the frequency of using make-up were negative relations with menopause symptoms (P = 0.0251) after climacteric. Smoking had made worse for physical symptoms (P < 0.001). Menopause symptoms are already experienced by younger women, especially, psychological symptoms. Also, physical conditions were influenced by smoking. Using make-up frequently was often seen after climacteric because of appearance changes by oestrogen dynamic decline. © 2012 The Authors. ICS © 2012 Society of Cosmetic Scientists and the Société Française de Cosmétologie. Source

Mitsukawa N.,Showa University | Satoh K.,Chiba University
Journal of Plastic, Reconstructive and Aesthetic Surgery | Year: 2010

Syndromic craniosynostosis is known to be associated with various obstructive respiratory disorders including sleep apnoea. We performed early midfacial distraction using a transfacial pinning technique in five syndromic craniosynostotic patients with obstructive respiratory disorders. Here, we report good results, indications and usefulness of this procedure. The subjects were five young children aged 7 months to 2 years who had respiratory disorders since birth due to midface hypoplasia. All subjects underwent midfacial distraction to avoid tracheotomy. The method involved Le Fort III osteotomy followed by the use of our original transfacial pinning system. This system consisted of devices connecting (1) transfacial pins penetrating the bilateral zygomatic bones and (2) Kirschner wires, which were passed through plates fixed on the bilateral temporal bones. The maxilla was distracted anteriorly at least 20 mm. Distraction was evaluated by comparing the pre- and postoperative polysomnography (PSG) and cephalograms. All patients had markedly improved respiratory conditions after distraction, and a tracheotomy was avoided. Postoperative PSG and cephalograms also showed great improvements compared with preoperative findings. A transfacial pinning system was considered useful and can be the most suitable method for early midfacial distraction in syndromic craniosynostosis with obstructive respiratory disorders. © 2009 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved. Source

Background/Aims: Intratumoral hemodynamics or tumor perfusion is useful in understanding the pathological background of the cancer. A parameter for a non-invasive, preoperative assessment of tumor perfusion has yet to be developed. Methods: The study included 50 patients who underwent surgery for gastric cancer. Perfusion computed tomography (P-CT) was performed using a 16-row multidetector CT, and tumor blood flow (ml/min/100 g tissue) values were measured. We compared blood flow with histopathological characteristics and evaluated its correlation with microvessel density and tumor stromal density and calculated the ratio of vessels and stromal tissue. Results: There was a significant decrease in blood flow in advanced tumor depth, peritoneal dissemination and undifferentiated subtypes. Cases with Lauren's diffuse type carcinoma were found to have decreased blood flow compared to the mixed or intestinal type. As for the stromal structure, despite the lack of correlation with microvessel density, blood flow significantly decreased with increased stromal density. Conclusions: Decreased blood flow value acquired from P-CT may reflect a progressive state of gastric cancer. The pathological background for this relation involves the tumor stroma. Tumor perfusion decreased as the stage and malignant character of the tumor advanced, and therefore P-CT could be a better strategy to estimate the malignancy level of cancer. Copyright © 2010 S. Karger AG, Basel. Source

Fujii S.,Chiba University | Jian C.,Ericsson AB
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control | Year: 2012

We have developed a diamond SAW resonator capable of operating at frequencies over 3 GHz using a SiO2/interdigital transducer (IDT)/AlN/diamond structure. This structure is expected to have a high Q value and a zero temperature coefficient of frequency (TCF) over 3 GHz, based on the high acoustic velocity of AlN. The SAW characteristics of various layered structures composed of SiO2/IDT/AlN/diamond substrates were studied both theoretically and experimentally. The SiO2/IDT/AlN/diamond substrate structure allows for a thicker IDT metal layer compared with other SAW device designs, such as the SiO2/IDT/ZnO/diamond structure. The thicker metal IDT in the present design leads to a lower series resistance and, in turn, a low insertion loss for SAW devices over 3 GHz. Using a second-mode (Sezawa-mode) SAW, the phase velocity and electromechanical coupling coefficient of the SiO2/IDT/AlN/diamond substrate reached the larger values of 11 150 m/s and 0.5%, respectively, and a zero TCF characteristic at 25°C was achieved. One-port SAW resonators fabricated from diamond substrates showed a high Q of 660 at 5.4 GHz. The frequency drift over a temperature range of-25°C to 80°C was about 90 ppm, even less than that for STquartz SAW substrates. A two-port resonator showed a low insertion loss of 8 dB at 5.4 GHz. Finally, we designed a 5-GHz band-stop SAW filter. A 30-MHz-wide stopband at a-6-dB rejection level was achieved while keeping the passband insertion loss to 0.76 dB. These characteristics of these filters show good potential for SHF-band filters. © 2012 IEEE. Source

Abe A.,Chiba University
IEEE International Conference on Data Mining Workshops, ICDMW | Year: 2015

In this paper, we introduce the concept of 'value' to the abduction procedure. In fact, 'values' are dealt with outside of the abduction procedure. For usual abduction, we always consider values included in the knowledge (hard coded). However, for a certain procedure, such values are unnecessary and sometimes harmful. Outside of the main abduction procedure, the inference system can flexibly deal with 'values' to generate hypotheses considering the user's preference, situation, and the current trends, etc. In addition, we introduce the concept of the expiration of the hypothesis in the hypothesis generation. Recently generated hypotheses are not generated during such abduction procedure, in addition. Accordingly, the system can generate rather novel hypotheses to enjoy potential chances. This type of inference can be applied to daily life situations. Of course, according to application such as recommendation strategies in shops. The opposite strategy can be conducted. © 2014 IEEE. Source

Matsumoto Y.,Chiba University | Amano T.,University of Tokyo | Hoshino M.,University of Tokyo
Astrophysical Journal | Year: 2012

Electron accelerations at high Mach number collisionless shocks are investigated by means of two-dimensional electromagnetic particle-in-cell simulations with various Alfvén Mach numbers, ion-to-electron mass ratios, and the upstream electron βe (the ratio of the thermal pressure to the magnetic pressure). We find electrons are effectively accelerated at a super-high Mach number shock (MA 30) with a mass ratio of M/m = 100 and βe = 0.5. The electron shock surfing acceleration is an effective mechanism for accelerating the particles toward the relativistic regime even in two dimensions with a large mass ratio. Buneman instability excited at the leading edge of the foot in the super-high Mach number shock results in a coherent electrostatic potential structure. While multi-dimensionality allows the electrons to escape from the trapping region, they can interact with the strong electrostatic field several times. Simulation runs in various parameter regimes indicate that the electron shock surfing acceleration is an effective mechanism for producing relativistic particles in extremely high Mach number shocks in supernova remnants, provided that the upstream electron temperature is reasonably low. © 2012. The American Astronomical Society. All rights reserved. Source

Berne O.,Toulouse 1 University Capitole | Berne O.,Roche Holding AG | Matsumoto Y.,Chiba University
Astrophysical Journal Letters | Year: 2012

Hydrodynamical instabilities are believed to power some of the small scale (0.1-10 pc) turbulence and chemical mixing in the interstellar medium. Identifying such instabilities has always been difficult, but recent observations of a wavelike structure (the Ripples) in the Orion nebula have been interpreted as a signature of the Kelvin-Helmholtz instability (KHI), occurring at the interface between the H II region and the molecular cloud. However, this has not been verified theoretically. In this Letter, we investigate theoretically the stability of this interface using observational constraints for the local physical conditions. A linear analysis shows that the H II/molecular cloud interface is indeed KH unstable for a certain range of magnetic field orientation. We find that the maximal growth rates correspond to typical timescales of a few 104 years and instability wavelengths of 0.06-0.6 pc. We predict that after 2 × 105 years the KHI saturates and forms a turbulent layer of about 0.5 pc. The KHI can remain in linear phase over a maximum distance of 0.75 pc. These spatial and timescales are compatible with the Ripples representing the linear phase of the KHI. These results suggest that the KHI may be crucial to generate turbulence and to bring heavy elements injected by the winds of massive stars in H II regions to colder regions where planetary systems around low-mass stars are being formed. This could apply to the transport of 26Al injected by a massive star in an H II region to the nascent solar system. © 2012. The American Astronomical Society. All rights reserved. Source

Nikoh N.,Chiba University | Hosokawa T.,Japan National Institute of Advanced Industrial Science and Technology | Oshima K.,University of Tokyo | Hattori M.,University of Tokyo | Fukatsu T.,Japan National Institute of Advanced Industrial Science and Technology
Genome Biology and Evolution | Year: 2011

Obligate endocellular symbiotic bacteria of insects and other organisms generally exhibit drastic genome reduction. Recently, it was shown that symbiotic gut bacteria of some stinkbugs also have remarkably reduced genomes. Here, we report the complete genome sequence of such a gut bacterium Ishikawaella capsulata of the plataspid stinkbug Megacopta punctatissima. Gene repertoire and evolutionary patterns, including AT richness and elevated evolutionary rate, of the 745,590 bp genome were strikingly similar to those of obligate c-proteobacterial endocellular insect symbionts like Buchnera in aphids and Wigglesworthia in tsetse flies. Ishikawaella was suggested to supply essential amino acids for the plant-sucking stinkbug as Buchnera does for the host aphid. Although Buchnera is phylogenetically closer to Wigglesworthia than to Ishikawaella, in terms of gene repertoire Buchnera was similar to Ishikawaella rather than to Wigglesworthia, providing a possible case of genome-level convergence of gene content. Meanwhile, several notable differences were identified between the genomes of Ishikawaella and Buchnera, including retention of TCA cycle genes and lack of flagellum-related genes in Ishikawaella, which may reflect their adaptation to distinct symbiotic habitats. Unexpectedly, Ishikawaella retained fewer genes related to cell wall synthesis and lipid metabolism than many endocellular insect symbionts. The plasmid of Ishikawaella encoded genes for arginine metabolism and oxalate detoxification, suggesting the possibility of additional Ishikawaella roles similar to those of human gut bacteria. Our data highlight strikingly similar evolutionary patterns that are shared between the extracellular and endocellular insect symbiont genomes. © The Author(s) 2010. Source

Inderbitzin P.,University of California at Davis | Bostock R.M.,University of California at Davis | Davis R.M.,University of California at Davis | Usami T.,Chiba University | And 2 more authors.
PLoS ONE | Year: 2011

Knowledge of pathogen biology and genetic diversity is a cornerstone of effective disease management, and accurate identification of the pathogen is a foundation of pathogen biology. Species names provide an ideal framework for storage and retrieval of relevant information, a system that is contingent on a clear understanding of species boundaries and consistent species identification. Verticillium, a genus of ascomycete fungi, contains important plant pathogens whose species boundaries have been ill defined. Using phylogenetic analyses, morphological investigations and comparisons to herbarium material and the literature, we established a taxonomic framework for Verticillium comprising ten species, five of which are new to science. We used a collection of 74 isolates representing much of the diversity of Verticillium, and phylogenetic analyses based on the ribosomal internal transcribed spacer region (ITS), partial sequences of the protein coding genes actin (ACT), elongation factor 1-alpha (EF), glyceraldehyde-3-phosphate dehydrogenase (GPD) and tryptophan synthase (TS). Combined analyses of the ACT, EF, GPD and TS datasets recognized two major groups within Verticillium, Clade Flavexudans and Clade Flavnonexudans, reflecting the respective production and absence of yellow hyphal pigments. Clade Flavexudans comprised V. albo-atrum and V. tricorpus as well as the new species V. zaregamsianum, V. isaacii and V. klebahnii, of which the latter two were morphologically indistinguishable from V. tricorpus but may differ in pathogenicity. Clade Flavnonexudans comprised V. nubilum, V. dahliae and V. longisporum, as well as the two new species V. alfalfae and V. nonalfalfae, which resembled the distantly related V. albo-atrum in morphology. Apart from the diploid hybrid V. longisporum, each of the ten species corresponded to a single clade in the phylogenetic tree comprising just one ex-type strain, thereby establishing a direct link to a name tied to a herbarium specimen. A morphology-based key is provided for identification to species or species groups. © 2011 Inderbitzin et al. Source

Hase A.,Saitama Institute of Technology | Mishina H.,Chiba University | Wada M.,Kanagawa University
Wear | Year: 2012

The recognition of wear mechanisms is important for effective maintenance of dynamic machinery, because the selection of an appropriate maintenance solution is dependent on the particular mechanism of wear that occurs at the frictional interface. To permit the recognition of wear mechanisms by means of an acoustic emission (AE) monitoring technique, the features of AE signals generated during adhesive wear and during abrasive mechanical wear were examined. For adhesive wear, friction and wear experiments were conducted by using a micro-sliding friction tester of the pin-on-block type with various combinations of pure metals that showed different adhesion forces. For abrasive wear, the experiments were conducted by rubbing an iron pin on emery papers with various grain sizes. AE signal waveforms generated in each wear mechanism were recorded and a frequency analysis was performed. AE signals detected during adhesive wear showed a large peak in the high-frequency region, whereas AE signals detected during abrasive wear showed a few peaks in the low-frequency region. These results permit the recognition of wear mechanisms by the AE technique. © 2012 Elsevier B.V. Source

Hosokawa T.,Japan National Institute of Advanced Industrial Science and Technology | Kikuchi Y.,Japan National Institute of Advanced Industrial Science and Technology | Nikoh N.,Chiba University | Fukatsu T.,Japan National Institute of Advanced Industrial Science and Technology
Applied and Environmental Microbiology | Year: 2012

Symbiotic bacteria associated with midgut crypts of stinkbugs of the family Cydnidae, representing seven species and 13 populations, were investigated. All of the symbionts were species specific, and constituted at least four distinct lineages in the Gammaproteobacteria, indicating multiple evolutionary origins of the gut symbionts among the burrower bugs. © 2012, American Society for Microbiology. Source

Inoue R.,Chiba University | Kuniba A.,University of Tokyo | Takagi T.,Japan National Defense Academy
Journal of Physics A: Mathematical and Theoretical | Year: 2012

The boxball system is an integrable cellular automaton on a one-dimensional lattice. It arises from either quantum or classical integrable systems by procedures called crystallization and ultradiscretization, respectively. The double origin of the integrability has endowed the boxball system with a variety of aspects related to YangBaxter integrable models in statistical mechanics, crystal base theory in quantum groups, combinatorial Bethe ansatz, geometric crystals, classical theory of solitons, tau functions, inverse scattering method, action-angle variables and invariant tori in completely integrable systems, spectral curves, tropical geometry and so forth. In this review, we demonstrate these integrable structures of the boxball system and its generalizations based on the developments in the last two decades. Dedicated to the memory of Professor Miki Wadati © 2012 IOP Publishing Ltd. Source

Moriyoshi Y.,Chiba University | Iida M.,Yamaha
SAE International Journal of Fuels and Lubricants | Year: 2010

In a motorcycle gasoline engine, the port fuel injection system is rapidly spread. Compared to an automotive engine, the injected fuel does not impinge on the intake valve due to space restriction to install the injector. In addition, as the air flow inside the intake pipe may become very fast and has large cycle-to-cycle variation, it is not well found how the injector should be installed in the intake pipe to prepare "good" fuel-air mixture inside the intake pipe. In this study, the formation process of the fuel-air mixture is measured by using ILIDS system that is a 2-D droplets' size and velocity measurement system with high spatial resolution. Experiments with changing conditions such as flow speed and injection direction are carried out. As a result, the effects of injection direction, ambient flow speed and wall roughness on the fuel-air mixture formation process was examined, considering the three conditions of cold start, light to medium load operation and high load operation. © 2010 SAE International. Source

Objective: To evaluate the impact of the policy to encourage nursing homes to provide end-of-life care by comparing facility and resident variables associated with dying within the nursing home and not in hospitals, and by comparing life sustaining treatment (LST) respectively provided. Method: Questionnaires mailed to an 11% random sample of 653 nursing homes in 2009. Facility characteristics from 371 nursing homes (57%) and resident characteristics of the 1158 who had been discharged due to death were obtained from 241 facilities (37%). Results: Facility characteristics related to dying in nursing homes were their policy of providing end-of-life care and physicians being based in home care supporting clinics. Resident characteristics related were not having pneumonia as the cause of death, the family's preference of the nursing home as the site of death and agreement within the family. Preferences on the use of LST were adhered more in residents who had died in nursing homes. Conclusion: Although the percentage of residents dying within the facility has increased, the nursing home as a site of death still composes only 3.2% of the total. To increase the latter, nursing homes should refocus their function to providing end-of-life care to those not preferring aggressive treatment. © 2012 Elsevier Ireland Ltd. Source

Norris V.,University of Rouen | Reusch R.N.,Michigan State University | Igarashi K.,Chiba University | Root-Bernstein R.,Michigan State University
Biology Direct | Year: 2015

Background: Fundamental problems faced by the protocells and their modern descendants include how to go from one phenotypic state to another; escape from a basin of attraction in the space of phenotypes; reconcile conflicting growth and survival strategies (and thereby live on 'the scales of equilibria'); and create a coherent, reproducible phenotype from a multitude of constituents. Presentation of the hypothesis: The solutions to these problems are likely to be found with the organic and inorganic molecules and inorganic ions that constituted protocells, which we term SUMIs for Simple Universal Molecules and Ions. These SUMIs probably included polyphosphate (PolyP) as a source of energy and of phosphate; poly-(R)-3-hydroxybutyrate (PHB) as a source of carbon and as a transporter in association with PolyP; polyamines as a source of nitrogen; lipids as precursors of membranes; as well as peptides, nucleic acids, and calcium. Here, we explore the hypothesis that the direct interactions between PHB, PolyP, polyamines and lipids - modulated by calcium - played a central role in solving the fundamental problems faced by early and modern cells. Testing the hypothesis: We review evidence that SUMIs (1) were abundant and available to protocells; (2) are widespread in modern cells; (3) interact with one another and other cellular constituents to create structures with new functions surprisingly similar to those of proteins and RNA; (4) are essential to creating coherent phenotypes in modern bacteria. SUMIs are therefore natural candidates for reducing the immensity of phenotype space and making the transition from a "primordial soup" to living cells. Implications of the hypothesis: We discuss the relevance of the SUMIs and their interactions to the ideas of molecular complementarity, composomes (molecular aggregates with hereditary properties based on molecular complementarity), and a prebiotic ecology of co-evolving populations of composomes. In particular, we propose that SUMIs might limit the initial phenotype space of composomes in a coherent way. As examples, we propose that acidocalcisomes arose from interactions and self-selection among SUMIs and that the phosphorylation of proteins in modern cells had its origin in the covalent modification of proteins by PHB. Reviewers: This article was reviewed by Doron Lancet and Kepa Ruiz-Mirazo. © 2014 Norris et al.; licensee BioMed Central Ltd. Source

To report a series of 6 cases of sterile endophthalmitis that developed consecutively after an intravitreal injection of bevacizumab (IVB). On April 13 and 14, 2009, we performed IVB for consecutive 12 eyes of 12 patients in a sterile condition. Within two days after injection, blurred vision without ocular pain, anterior chamber inflammation, and vitreous opacity were developed in 6 of the eyes of 6 patients. Hypopyon was not observed in any patient. Anterior chamber fluid from each eye and all syringes of bevacizumab that have been separated from the same bottle of same lot number were sent for bacterial culture examination. No bacterial colony was developed from the anterior chamber fluid of any of the patients nor from any of the syringes. Antibiotic treatment of all 6 patients was unsuccessful. The symptoms improved in all cases following treatment with topical corticosteroid within several days. Both the clinical course and the results of bacterial culture, lead to the possibility that our patients developed sterile endophthalmitis rather than infectious endophthalmitis. The exact causes of the endophthalmitis were not identified in our cases, but similar events are reported by several institutions, endophthalmitis following IVB needs to be considered a possibility. Source

Tatsumi K.,Chiba University
Japan Medical Association Journal | Year: 2011

"Guidelines for the Diagnosis and Treatment of COPD (Chronic Obstructive Pulmonary Disease)" of The Japanese Respiratory Society was revised for the first time in 5 years, and the third edition was published in June 2009. This edition of the guidelines has 4 major purposes, namely: 1) guarantee of high quality healthcare, 2) standardization of healthcare, 3) increased transparency of healthcare, and 4) improved efficiency of medical economics. A comprehensive view of the pharmacotherapy in COPD is as follows. Pharmacotherapy using bronchodilators as the drugs of first choice is effective to alleviate symptoms, prevent exacerbations, enhance health-related quality of life (HRQOL), and improve exercise tolerance. Therefore, the pharmacotherapy for COPD patients should be actively utilized. However, the clinical condition of each patient as well as the mechanism of action of each drug must be taken into consideration when treating COPD, using the guidelines as a reference. Accumulation of clinical experience of each physician should lead to future evidence, on which the next version of the guidelines will be prepared. Source

Watanabe N.,Center for Rheumatic Diseases | Nakajima H.,Chiba University
Clinical and Developmental Immunology | Year: 2012

Coinhibitory molecules such as CTLA-4, PD-1 and BTLA negatively regulate immune responses. Multiple studies indicate that the deficiency or mutation of coinhibitory molecules leads to the development of autoimmune diseases in mice and humans, indicating that the negative signals from coinhibitory molecules are crucial for the prevention of autoimmunity. In some conditions, the administration of decoy coinhibitory receptors (e.g., CTLA-4 Ig) or mAb against coinhibitory molecules suppresses the responses of self-reactive T cells in autoimmune diseases. Therefore, modulation of coinhibitory signals seems to be an attractive approach to induce tolerance in autoimmune diseases in humans where the disease-inducing self-antigens are not known. Particularly, administration of CTLA-4 Ig has shown great promise in animal models of autoimmune diseases and has been gaining increasing attention in clinical investigation in several autoimmune diseases in humans. © 2012 Norihiko Watanabe and Hiroshi Nakajima. Source

Mase K.,Chiba University
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2014

The IceCube detector is unique. It uses the Antarctic glacial ice as an interaction and detection medium. An array of optical sensors observes Cherenkov light from secondary charged particles resulting from neutrino interactions. The high transparency of the ice enabled the realization of a 1 km3 large detection volume in order to detect rarely interacting particles. Neutrinos are ideal probes of the deep universe because they rarely interact with matter and propagate in straight lines. Neutrinos are thought to be produced in hadronic processes at astronomical sources such as active galactic nuclei and gamma-ray bursts. IceCube aims to detect neutrinos from such astronomical sources. IceCube recently found 28 events in an energy range approximately from 50 TeV to 1 PeV. These events are not easily explained by background derived from atmospheric origin, and therefore represent the first evidence for high energy neutrinos from an extraterrestrial origin. IceCube can also perform elementary particle physics by searching for neutrinos from SUSY particles such as neutralinos and measuring atmospheric neutrino oscillations. An overview of the latest IceCube results is provided in this paper including the 28 candidate observations and the corresponding implications. ©2014 Elsevier B.V. All rights reserved. Source

Gently undulating waveforms were identified in conglomerates and pebbly sandstones of the lower Pleistocene Higashihigasa Formation, which represents an infill of a submarine canyon on the Boso Peninsula, Japan. On the basis of dimension, geometry, and texture, these waveforms are interpreted as bedforms that are analogous to coarse-grained sediment waves in modern deep-water environments. The studied waveforms exhibit symmetrical or dune-like asymmetrical forms, in association with minor antidune-like asymmetrical forms with the lee sides being longer than the stoss sides. The waveforms are also characterized internally by bedding gently inclined in the downstream direction to the northeast. Laterally, washout-dune and humpback-dune deposits are locally developed in association with planar bedding. The coarse-grained sediment-wave deposits are interpreted to have developed as downstream-migrating antidunes in the upper-flow-regime condition of turbidity currents. On the basis of the empirical relationship between the wavelengths and mean flow depths of downstream-migrating gravel antidunes, the waveforms are interpreted to have been formed by waves at the interface between the denser bottom-flow and the less-dense upper-flow within a turbidity current. It is possible that some of the coarse-grained sediment waves in modern deep-water environments may have been formed as downstream-migrating antidunes, regardless of their plan-view geometry. © 2010 Elsevier B.V. Source

The purpose of this study was to clarify the incidence of (CS)-associated osteonecrosis among different underlying diseases and to evaluate the risk factors for steroid-associated osteonecrosis in a prospective MRI study. We prospectively used MRI to study 337 eligible underlying disease patients requiring CS therapy and succeeded in examining 1199 joints (hips and knees) in 302 patients with MRI for at least 1 year starting immediately after the onset of CS therapy (1-year follow-up rate of 90%). The underlying diseases included SLE in 687 joints (173 patients) and a variety of other rheumatological disorders in 512 joints (129 patients). The incidence of osteonecrosis was significantly higher in SLE patients than in non-SLE patients (37 vs 21%, P = 0.001). Logistic regression analysis revealed that adolescent and adult patients had a significantly higher risk of osteonecrosis compared with paediatric patients [odds ratio (OR) = 13.2], that high daily CS dosage (>40 mg/day) entailed a significantly higher risk of osteonecrosis compared with the dosage of <40 mg/day (OR = 4.2), that SLE patients had a significantly higher risk of osteonecrosis compared with non-SLE patients (OR = 2.6) and that male patients had a significantly higher risk of osteonecrosis compared with female patients (OR = 1.6). These findings suggest that the incidence of CS-associated osteonecrosis varies among different underlying diseases. Source

Yagai S.,Chiba University
Bulletin of the Chemical Society of Japan | Year: 2015

As details of exciting photonic and electronic properties arising from self-assembled functional dyes and related π-conjugated molecules become clearer, strategies for control of short and long-range chromophore-chromophore orientations, regulation of π-π stacking arrangements, construction of self-organized nano-to-microscale architectures, diversification of materials properties, analysis of self-assembly pathways, and impartment of stimuli-responsive properties, are all becoming important issues in the research area of organic functional materials. This article focuses on the supramolecular assemblies of dyes and related π-conjugated systems whose organization processes are rationally controlled by complementary multiple hydrogen bonding (CMHB) interactions between melamine and barbituric acid/ cyanurate functional units. The article includes an overview of the construction principle of such systems, but special attention is focused on the work carried out in the authors's group (since 2002) using azobenzene, diarylethene, merocyanine, perylene bisimide dyes, and π-conjugated oligomers including oligo(p-phenylenevinylene), oligo-(p-phenyleneethynylene), and oligothiophenes. The design principles discussed in this account could open up new avenues to novel functional aspect and application of functional dyes and small-molecular π-conjugated systems. © 2014 The Chemical Society of Japan. Source

Hashimoto K.,Chiba University | Malchow B.,Ludwig Maximilians University of Munich | Falkai P.,Ludwig Maximilians University of Munich | Schmitt A.,Ludwig Maximilians University of Munich | Schmitt A.,University of Sao Paulo
European Archives of Psychiatry and Clinical Neuroscience | Year: 2013

Severe psychiatric disorders such as schizophrenia are related to cognitive and negative symptoms, which often are resistant to current treatment approaches. The glutamatergic system has been implicated in the pathophysiology of schizophrenia and affective disorders. A key component is the dysfunction of the glutamatergic N-methyl-d-aspartate (NMDA) receptor. Substances regulating activation/inhibition of the NMDA receptor have been investigated in schizophrenia and major depression and are promising in therapeutic approaches of negative symptoms, cognition, and mood. In schizophrenia, add-on treatments with glycine, d-serine, d-alanine, d-cycloserine, d-amino acid oxidase inhibitors, glycine transporter-1 (GlyT-1) inhibitors (e.g., sarcosine, bitopertin) and agonists (e.g., LY2140023) or positive allosteric modulator (e.g., ADX71149) of group II metabotropic glutamate receptors (mGluRs) have been studied. In major depression, the NMDA receptor antagonists (e.g., ketamine, AZD6765), GluN2B subtype antagonists (e.g., traxoprodil, MK-0657), and partial agonists (e.g., d-cycloserine, GLYX-13) at the glycine site of the NMDA receptor have been proven to be effective in animal studies and first clinical trials. In addition, clinical studies of mGluR2/3 antagonist BCI-838 (a prodrug of BCI-632 (MGS0039)), mGluR2/3-negative allosteric modulators (NMAs) (e.g., RO499819, RO4432717), and mGluR5 NAMs (e.g., AZD2066, RO4917523) are in progress. Future investigations should include effects on brain structure and activation to elucidate neural mechanisms underlying efficacy of these drugs. © 2013 Springer-Verlag Berlin Heidelberg. Source

Sri Sumantyo J.T.,Chiba University
International Geoscience and Remote Sensing Symposium (IGARSS) | Year: 2012

Synthetic Aperture Radar (SAR) is well-known as a multi-purpose sensor that can be operated in all-weather and day-night time. The past SAR sensors for Earth observation mission are commonly operated in linear polarization that sensitive to Faraday rotation effect, especially in low frequency. This paper introduce our Circularly Polarized Synthetic Aperture Radar onboard Unmanned Aerial Vehicle (CP-SAR UAV) that is developed to retrieve the physical information of Earth surface for Earth diagnosis mission. The CP-SAR system is considered as small, light in weight and low power consumption system. The CP-SAR sensor is employing elliptical wave propagation and scattering phenomenon by radiating and receiving the elliptically polarized wave, including the special polarization as circular and linear polarizations. This paper introduces the CP-SAR and UAV system, including simulated full polarimetric CP-SAR images. © 2012 IEEE. Source

Kurosu M.,Chiba University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2015

In this paper, a history of usability concept is reviewed including Shackel and Richardson, Nielsen, and ISO standards to show how the usability is located among relevant quality characteristics. Secondly, the importance of subjective quality is emphasized in relation to the usability. Thirdly, the concept of quality in use is considered in relation to the usability. Finally, a new scheme on quality characteristics is presented. © Springer International Publishing Switzerland 2015. Source

Goto Y.,Tokyo International University | Goto Y.,Chiba University | Kurashima Y.,Tokyo International University | Kiyono H.,Tokyo International University
Current Opinion in Rheumatology | Year: 2015

Purpose of review Inflammatory bowel diseases (IBDs) reflect the cooperative influence of numerous host and environmental factors, including those of elements of the intestinal immune system, the gut microbiota, and dietary habits. This review focuses on features of the gut microbiota and mucosal immune system that are important in the development and control of IBDs. Recent findings Gut innate-type immune cells, including dendritic cells, innate lymphoid cells, and mast cells, educate acquired-type immune cells and intestinal epithelial cells to achieve a symbiotic relationship with commensal bacteria. However, perturbation of the number or type of commensal microorganisms and endogenous genetic polymorphisms that affect immune responses and epithelial barrier system can ultimately lead to IBDs. Providing beneficial bacteria or fecal microbiota transplants helps to reestablish the intestinal environment, maintain its homeostasis, and ameliorate IBDs. Summary The gut immune system participates in a symbiotic milieu that includes cohabiting commensal bacteria. However, dysbiotic conditions and aberrations in the epithelial barrier and gut immune system can disrupt the mutualistic relationship between the host and gut microbiota, leading to IBDs. Progress in our molecular and cellular understanding of this relationship has yielded numerous insights regarding clinical applications for the treatment of IBDs. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved. Source

Fujii S.,Chiba University
Physica Status Solidi (A) Applications and Materials Science | Year: 2011

This paper gives an overview of recent progress in developing diamond surface acoustic wave (SAW) devices for high-frequency applications. We have studied high-frequency SAW filters or resonators based on diamond thin films and demonstrated that diamond thin films have much potential for SAW applications above 3 GHz. Diamond film characteristics required for SAW filters in high-frequency applications are clarified. The results of numerical calculations reveal that the diamond-based SAW device, which employs a LiNbO 3 thin film as the piezoelectric material, can provide a high electric coupling factor as well as a high phase velocity of more than 12 000 m/s. In contrast to when an AlN thin film is used as the piezoelectric material, the use of a SiO 2/interdigital transducer/AlN/diamond structure enables the SAW device to have a low insertion loss for applications above 3 GHz. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Kuwabara S.,Chiba University | Yuki N.,National University of Singapore
The Lancet Neurology | Year: 2013

Acute motor axonal neuropathy (AMAN) is a pure motor axonal subtype of Guillain-Barré syndrome (GBS) that was identified in the late 1990s. In Asia and Central and South America, it is the major subtype of GBS, seen in 30-65% of patients. AMAN progresses more rapidly and has an earlier peak than demyelinating GBS; tendon reflexes are relatively preserved or even exaggerated, and autonomic dysfunction is rare. One of the main causes is molecular mimicry of human gangliosides by Campylobacter jejuni lipo-oligosaccharides. In addition to axonal degeneration, electrophysiology shows rapidly reversible nerve conduction blockade or slowing, presumably due to pathological changes at the nodes or paranodes. Autoantibodies that bind to GM1 or GD1a gangliosides at the nodes of Ranvier activate complement and disrupt sodium-channel clusters and axoglial junctions, which leads to nerve conduction failure and muscle weakness. Improved understanding of the disease mechanism and pathophysiology might lead to new treatment options and improve the outlook for patients with AMAN. © 2013 Elsevier Ltd. Source

Sakuma S.,Japan National Institute of Agrobiological Science | Sakuma S.,Chiba University | Salomon B.,Swedish University of Agricultural Sciences | Komatsuda T.,Japan National Institute of Agrobiological Science
Plant and Cell Physiology | Year: 2011

The process of crop domestication began 10,000 years ago in the transition of early humans from hunter/gatherers to pastoralists/farmers. Recent research has revealed the identity of some of the main genes responsible for domestication. Two of the major domestication events in barley were (i) the failure of the spike to disarticulate and (ii) the six-rowed spike. The former mutation increased grain yield by preventing grain loss after maturity, while the latter resulted in an up to 3-fold increase in yield potential. Here we provide an overview of the disarticulation systems and inflorescence characteristics, along with the genes underlying these traits, occurring in the Triticeae tribe. © 2011 The Author. Source

Matsuoka M.,Japan National Institute of Advanced Industrial Science and Technology | Yamazaki F.,Chiba University
Journal of Applied Remote Sensing | Year: 2010

Earthquakes that have caused large-scale damage in developed areas, such as the 1994 Northridge and 1995 Kobe events, remind us of the importance of making quick damage assessments in order to facilitate the resumption of normal activities and restoration planning. Synthetic aperture radar (SAR) can be used to record physical aspects of the Earth's surface under any weather conditions, making it a powerful tool in the development of an applicable method for assessing damage following natural disasters. Detailed building damage data recorded on the ground following the 1995 Kobe earthquake may provide an invaluable opportunity to investigate the relationship between the backscattering properties and the degree of damage. This paper aims to investigate the differences between the backscattering coefficients and the correlations derived from pre-and post-earthquake SAR intensity images to smoothly detect areas with building damage. This method was then applied to SAR images recorded over the areas affected by the 1999 Kocaeli earthquake in Turkey, the 2001 Gujarat earthquake in India, and the 2003 Boumerdes earthquake in Algeria. The accuracy of the proposed method was examined and confirmed by comparing the results of the SAR analyses with the field survey data. © 2010 Society of Photo-Optical Instrumentation Engineers. Source

Fujii K.,Chiba University | Miyashita T.,Kitasato University
Pediatrics International | Year: 2014

Gorlin syndrome, also called nevoid basal cell carcinoma syndrome, is an autosomal dominant neurocutaneous disease characterized by developmental anomalies such as palmar pits and rib anomaly, and tumorigenesis such as medulloblastoma and basal cell carcinoma. This syndrome is mainly caused by a mutation of PTCH1, a human homologue of Drosophila patched, including frameshift, missense, or nonsense mutations. Genotype-phenotype correlation has not been established. PTCH1 is a member of hedgehog signaling, which is a highly conserved pathway in vertebrates, composed of hedgehog, SMO, and GLI proteins as well as PTCH1. Given that hedgehog signaling regulates cell growth and development, disorder of this pathway gives rise to not only developmental anomalies but also diverse tumors such as those seen in Gorlin syndrome. We recently reported, for the first time, a nationwide survey of Gorlin syndrome in Japan, noting that the frequency was 1/235 800 in the Japanese population, and that the frequency of basal cell carcinomas was significantly lower in Japan than in the USA and Europe, suggesting that ethnicity and genetic background contribute to these differences. Given that many clinical trials using newly discovered molecular inhibitors are still ongoing, these agents should become the new therapeutic options for hedgehog pathway-dependent tumors in patients with or without Gorlin syndrome. © 2014 Japan Pediatric Society. Source

Rowley S.,Aurora University | Liang L.-P.,Aurora Pharmaceutical | Fulton R.,Aurora Pharmaceutical | Shimizu T.,Chiba University | And 3 more authors.
Neurobiology of Disease | Year: 2015

Metabolic alterations have been implicated in the etiology of temporal lobe epilepsy (TLE), but whether or not they have a functional impact on cellular energy producing pathways (glycolysis and/or oxidative phosphorylation) is unknown. The goal of this study was to determine if alterations in cellular bioenergetics occur using real-time analysis of mitochondrial oxygen consumption and glycolytic rates in an animal model of TLE. We hypothesized that increased steady-state levels of reactive oxygen species (ROS) initiated by epileptogenic injury result in impaired mitochondrial respiration. We established methodology for assessment of bioenergetic parameters in isolated synaptosomes from the hippocampus of Sprague-Dawley rats at various times in the kainate (KA) model of TLE. Deficits in indices of mitochondrial respiration were observed at time points corresponding with the acute and chronic phases of epileptogenesis. We asked if mitochondrial bioenergetic dysfunction occurred as a result of increased mitochondrial ROS and if it could be attenuated in the KA model by pharmacologically scavenging ROS. Increased steady-state ROS in mice with forebrain-specific conditional deletion of manganese superoxide dismutase (Sod2fl/flNEXCre/Cre) in mice resulted in profound deficits in mitochondrial oxygen consumption. Pharmacological scavenging of ROS with a catalytic antioxidant restored mitochondrial respiration deficits in the KA model of TLE. Together, these results demonstrate that mitochondrial respiration deficits occur in experimental TLE and ROS mechanistically contribute to these deficits. Furthermore, this study provides novel methodology for assessing cellular metabolism during the entire time course of disease development. © 2015 Elsevier Inc. Source

Tsubota K.-i.,Chiba University | Wada S.,Osaka University
International Journal of Mechanical Sciences | Year: 2010

The elastic force of a red blood cell (RBC) membrane during its tank-treading motion was estimated using a three-dimensional spring network model. An RBC membrane was modelled by an assembly of triangular elements in which stretch/compression and bending springs were placed to express planar shear and out-of-plane bending deformations, respectively. An areal incompressibility of the membrane and a volumetric constraint on the entire RBC were taken into account. Different natural states of an RBC membrane were considered by adjusting reference lengths and angles of the stretch/compression and bending springs, respectively. An elastic motion simulation was conducted using the spring network model to reproduce a tank-treading motion of the membrane for a constant biconcave discoid RBC under a fluid shear force. Given the simulated tank-treading motion, an additional membrane elastic force due to the motion was determined from the elastic energy changes during the motion. It was confirmed that the natural state of the RBC membrane should be nonuniform to generate the additional elastic force. Greater spring constants and greater natural state nonuniformity induced a greater additional elastic force, and the elastic force was regarded as a resistance against the tank-treading motion. Additional elastic forces due to the membrane tank-treading motion for different sets of spring constants and natural state nonuniformity values were determined, and they were compared with fluid shear forces at shear rates within the range of which a transition between tank-treading and tumbling motions of an RBC occurs in experiments. The results suggested that for the experimentally measured elastic moduli, natural state nonuniformity in a physiological state is moderate between that for a spherical or flat shape and that for the biconcave shape. Moderate nonuniformity was also confirmed by a simulated RBC shape in a minimum state of elastic energy. © 2009 Elsevier Ltd. All rights reserved. Source

Tanaka T.,Chiba University
Nihon rinsho. Japanese journal of clinical medicine | Year: 2011

Cellular senescence is a complexity of ageing and cancer biology. As malignant tumors can culminate individuals in life-termination, evolution has provided multicellular organisms with an acquisition of distinctive safety device, cellular senescence, to circumvent the development. Diploid cells, indeed, sense accumulation of hostile stresses such as genomic integrity, metabolic dysfunction and oncogene-induced mitotic signals, leading to activation of cell cycle arrest and/or programmed cell death. A tumor suppressor, p53, has been reported to function as a governing center to defend against these malignant transformations. Here we review how p53 cooperate with adverse stresses to drive cellular senescence, providing a framework for intricate molecular cross-talks. Source

Nakada H.,Chiba University
Physical Review C - Nuclear Physics | Year: 2010

Shell structure in the neutron-rich Ca and Ni nuclei is investigated by the spherical Hartree-Fock calculations with semi-realistic NN interactions. Specific ingredients of the effective interaction, particularly the tensor force, often play a key role in the Z dependence of the neutron shell structure. Such examples are found in N=32 and N=40; N=32 becomes magic or submagic in Ca52 while its magicity is broken in Ni60, and N=40 is submagic (though not magic) in Ni68 but not in Ca60. Comments are given on the doubly magic nature of Ni78. We point out that the loose binding can lead to a submagic number N=58 in Ni86, assisted by the weak pair coupling. © 2010 The American Physical Society. Source

Liu J.Y.,National Central University | Chen Y.I.,National Central University | Chen C.H.,Kyoto University | Hattori K.,Chiba University
Journal of Geophysical Research: Space Physics | Year: 2010

We report seismo-ionospheric precursors of anomalous decreases in the total electron content (TEC) appearing day 5 prior to an M9.3 earthquake, the largest one in the last five decades, which occurred in Sumatra-Andaman, Indonesia on 26 December 2004. Sequences of global ionosphere maps of the TEC derived from worldwide ground-based receivers of the global positioning system (GPS) are used to statistically study the temporal and spatial precursors of the earthquake. It was found that the temporal precursor of the GPS TEC around the epicenter was significantly reduced during the afternoon period on d 5 before the earthquake. The spatial precursors prominently, persistently, and simultaneously appear around the epicenter and its conjugate areas of the Sumatra-Andaman earthquake. Copyright 2010 by the American Geophysical Union. Source

This report proposes a procedure to synthesize monodisperse Au nanoparticles of different mean sizes (6-15 nm) under a constitute reaction condition only by altering the interval time between additions of citric acid and NaOH solutions into boiling HAuCl4 solution without any growth modifiers. © 2013 The Royal Society of Chemistry. Source

Tomiya A.,Geological Survey of Japan | Takahashi E.,Tokyo Institute of Technology | Furukawa N.,Chiba University | Suzuki T.,Japan Agency for Marine - Earth Science and Technology
Journal of Petrology | Year: 2010

We estimated the depth of the magma chamber system beneath Usu volcano, one of the most active volcanoes in Japan, by melting experiments on the eruptive product of the AD 1663 plinian eruption (Us-b pumice).This pumice is a low-K rhyolite with a K2O content of only 1wt %. The experiments were conducted using internally heated pressure vessels at 98-392 MPa and 700-900° under nickel-nickel oxide (NNO)-buffered and water-saturated conditions. The pre-eruptive conditions of the 1663 eruption were estimated to be 780 - 20° and around 200-250 MPa. The phase equilibria, mineral compositions (plagioclase, orthopyroxene, and Fe-Ti oxides), melt composition, and melt fraction are all in agreement with this conclusion. This pressure corresponds to a depth of 8-10 km, assuming a lithostatic condition with an appropriate crustal density structure.The magma was at near water-saturated conditions. Deviation between the estimated pressure and the true total pressure was estimated to be less than 50 MPa. The Us-b magma was under very uniform conditions with a temperature variation of less than c.20°, deduced from the narrow range of the phase equilibrium conditions (crystallizing orthopyroxene without quartz) and the homogeneous composition of plagioclase (c.An41-45).We also estimated the pre-eruptive conditions of post-1663 eruptions, where it has been proposed that two magmas (high-P and low-P members) mixed prior to each eruption. The pressure of the deep magma was also around 200-250 MPa, whereas that of the shallow magma was estimated to be 100-150 MPa (4-6 km depth), according to the pressure dependence of the plagioclase composition obtained in our experiments. Thus, there appear to be two magma chambers beneath Usu volcano. Our estimate is consistent with geophysical observations made during the 2000 eruption, including identification of an inflation and deflation source at a depth of 10 km, a low-frequency (12 s) tremor source at a depth of 5-6 km, and an earthquake swarm at a depth of less than 4 km. The depth of the rhyolitic magma chamber (8-10 km) is deeper than the level of neutral buoyancy for the magma, and is comparable with that of mafic magma that existed beneath the rhyolitic magma.This suggests that the depth of the 8-10 km deep magma chamber was controlled by the emplacement of the mafic magma and that the rhyolitic magma was produced at that depth. When compared with other silicic magma systems, the Usu magma system has similar characteristics, including a similar pre-eruptive pressure of around 200 MPa and a pressure decrease with time, suggesting upward magma movement towards a neutral buoyancy level. The low potassium content of the Usu magma prohibited crystallization of biotite, K-feldspar or horn-blende, which are common phases in magmas with intermediate to high potassium contents. The absence of hydrous minerals at near-liquidus conditions may cause a rapid increase in water content during crystallization of the magma, resulting in a rapid increase of the gas phase and frequent plinian or sub-plinian eruptions (six times since AD 1663) of the volcano. © The Author 2010. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oxfordjournals.org. Source

Hashimoto K.,Chiba University
Journal of Pharmacological Sciences | Year: 2015

Endoplasmic reticulum (ER) protein sigma-1 receptor represents unique chaperone activity in the central nervous system, and it exerts a potent influence on a number of neurotransmitter systems. Several lines of evidence suggest that activation of sigma-1 receptor plays a role in the pathophysiology of neuropsychiatric diseases, as well as in the mechanisms of some therapeutic drugs and neurosteroids. Preclinical studies showed that some selective serotonin reuptake inhibitors (SSRIs; fluvoxamine, fluoxetine, excitalopram), donepezil, and ifenprodil act as sigma-1 receptor agonists. Furthermore, sigma-1 receptor agonists could improve the N-methyl-D-aspartate (NMDA) antagonist phencyclidine (PCP)-induced cognitive deficits in mice. A study using positron emission tomography have demonstrated that an oral administration of fluvoxamine or donepezil could bind to sigma-1 receptor in the healthy human brain, suggesting that sigma-1 receptor might be involved in the therapeutic mechanisms of these drugs. Moreover, case reports suggest that sigma-1 receptor agonists, including fluvoxamine, and ifenprodil, may be effective in the treatment of cognitive impairment in schizophrenia, delirium in elderly people, and flashbacks in post-traumatic stress disorder. In this review article, the author would like to discuss the clinical implication of sigma-1 receptor agonists, including endogenous neurosteroids, in the neuropsychiatric diseases. © 2014 Japanese Pharmacological Society. Source

Arai M.A.,Chiba University
Chemical and Pharmaceutical Bulletin | Year: 2011

We have developed "protein- and cell-based screen methods" for the isolation of new natural products. By using VDR (vitamin D receptor) immobilized magnetic beads, two new natural products were isolated rapidly. To find inhibitors of Hes1 protein, which is one of the important transcriptional factors in neural stem cells, a Hes1 dimer plate assay was developed, and then first Hes1 dimer inhibitors were found from our natural products library. As a "cell-based screen method," a reporter gene assay for screening Hh (hedgehog) signaling inhibitors was constructed. New Hh signaling inhibitors were isolated from our natural extracts library. We evaluated their Hh inhibitory activity in Hh related protein synthesis and cytotoxicity against cancers, in which Hh signaling is aberrantly activated. In addition to the naturally made compounds library (extracts library), "small molecules based on natural products" were synthesized. The total synthesis of Melleumin A, B, which were isolated by our group, was achieved. From their synthetic derivatives, inhibitors of the Wnt signal, which has been reported to cause colon cancers, were discovered. Moreover, flavanone and chromone were selected as natural product scaffolds. Many flavonoids and chromones with diverse heterocyclic units were constructed using our efficient synthetic method. © 2011 Pharmaceutical Society of Japan. Source

Kobayashi K.,Keio University | Hoshi M.,Chiba University
Frontiers in Zoology | Year: 2011

Background: The mechanisms underlying the switching from an asexual to a sexual mode of reproduction, and vice versa, remain unknown in metazoans. In planarians, asexual worms acquire cryptic sexuality when fed with sexual worms, indicating that sexual worms contain a sex-inducing substance. Although such a chemical compound will provide clues about the mechanisms underlying the switching, information on the sex-inducing substance is poor. In order to identify this substance, we have established an assay system for sexual induction in asexual worms of Dugesia ryukyuensis by feeding them with sexual worms. Here, we carried out an isolation study on the sex-inducing substance using this assay system.Results: After centrifugation of sexual worms homogenised in saline solution, we found that not only did the precipitate have a sex-inducing effect on the asexual worms, which has been shown previously, but the cytosolic fraction did as well. We confirmed that the sex-inducing activity in the cytosolic fraction was recovered in a hydrophilic fraction separated on an octadecylsilane (ODS) column. We showed that the sex-inducing substance in the hydrophilic fraction is papain-resistant and a putative low-molecular-weight compound of less than 500. We also suggest the presence of an enhancer of sexual induction with a molecular weight (MW) of more than 5 K in the hydrophilic fraction.Conclusion: Our experiments showed the existence of a sex-inducing substance and an enhancer of sex-induction in a hydrophilic fraction, and a putative hydrophobic sex-inducing substance in the precipitate. Sexual induction in the asexual worms might be triggered by additive or synergistic effects of these chemical compounds. © 2011 Kobayashi and Hoshi; licensee BioMed Central Ltd. Source

Iwadate Y.,Chiba University
Handbook on the Physics and Chemistry of Rare Earths | Year: 2014

There is a definite overlap between the concepts of molten salts and ionic liquids; however, the present tendency is to use "molten salts" to characterize melts of purely inorganic compounds. If theoretical modeling of ionic crystals is relatively easy to achieve from X-ray diffraction data in view of the periodic arrangements of ions in the structure, it becomes a much more involved process when molten salts are considered because of interparticle interactions due to collisions. A single experimental technique usually gives a partial picture of the situation only so that a multiple-technique approach has to be used combining for instance X-ray diffraction, vibrational spectroscopy, density measurements, molecular dynamics, and Monte Carlo calculations. The review first focuses on the definition of the radial distribution function and on the ways to estimate coordination numbers in the first and second shell from this function. It then describes the present knowledge for melts of rare-earth and alkali halides and further on concentrates on salts with polyatomic anions. The penetration of ions from the second into the first coordination sphere is discussed as well as the formation of polymeric ions and their clustering. Kinetic aspects are also given attention. © 2014 Elsevier B.V. Source

Shiina T.,Chiba University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2010

Nowadays air-flow and certain gas measurements in near range are needed as a lidar application. Lidar optics, however, has blind area because it takes a certain distance to overlap the transmitting beam and the receiver's field of view. To detect the near range lidar echo with the narrow field of view, the optical design should be adequate. In this study, several cases of concrete lidar systems for near range measurement will be introduced. The near range compact Raman lidar applications, here the author mainly explain, are hydrogen leakage gas detection up to 50m ahead, monitoring exhaust fume at an intersection, air-flow measurement for a closed space such as a exhibition hall, and so on. The system should be compact as the near range lidar. The optical design should be simple to accomplish the near range measurement. The author has started the theoretical calculation of the lidar echo simulation with the various types of optical designs such as biaxial, coaxial and inline optics, which has common optics for the transmitting and receiving optics. The signal-to-noise ratio will be also estimated in the viewpoint of lowering transmitting beam power for eye-safe. The near range from zero to a few hundred meters is a target distance. The calculated results were compared and evaluated with the optical specification of the actual lidar. Now, the studies are extended, and the several types of near range lidars were developed mainly for the disaster prediction. They are certain gas detection, heavy rain prediction and lightning stroke detection. The "inline" optics adapt to the various kinds of lidar techniques, such as usual Mie lidar, Raman lidar, and polarization lidar. In this report, such a variety of the inline lidars are also introduced. © 2010 SPIE. Source

Park C.,Korea Institute of Machinery and Materials | Kim C.,Korea Institute of Machinery and Materials | Choi Y.,Korea Institute of Machinery and Materials | Won S.,Korea Institute of Machinery and Materials | Moriyoshi Y.,Chiba University
International Journal of Hydrogen Energy | Year: 2011

Because blending hydrogen with natural gas can allow the mixture to burn leaner, reducing the emission of nitrogen oxide (NOx), hydrogen blended with natural gas (HCNG) is a viable alternative to pure fossil fuels because of the effective reduction in total pollutant emissions and the increased engine efficiency. In this research, the performance and emission characteristics of an 11-L heavy duty lean burn engine using HCNG were examined, and an optimization strategy for the control of excess air ratio and of spark advance timing was assessed, in consideration of combustion stability. The thermal efficiency increased with the hydrogen addition, allowing stable combustion under leaner operating conditions. The efficiency of NOx reduction is closely related to the excess air ratio of the mixture and to the spark advance timing. With the optimization of excess air ratio and spark advance timing, HCNG can effectively reduce NOx as much as 80%. © 2010, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved. Source

Yamakami I.,Chiba Central Medical Center | Ito S.,Neurosurgery | Higuchi Y.,Chiba University
Journal of Neurosurgery | Year: 2014

Object. Management of small acoustic neuromas (ANs) consists of 3 options: observation with imaging followup, radiosurgery, and/or tumor removal. The authors report the long-term outcomes and preservation of function after retrosigmoid tumor removal in 44 patients and clarify the management paradigm for small ANs. Methods. A total of 44 consecutively enrolled patients with small ANs and preserved hearing underwent retrosigmoid tumor removal in an attempt to preserve hearing and facial function by use of intraoperative auditory monitoring of auditory brainstem responses (ABRs) and cochlear nerve compound action potentials (CNAPs). All patients were younger than 70 years of age, had a small AN (purely intracanalicular/cerebellopontine angle tumor ≤ 15 mm), and had serviceable hearing preoperatively. According to the guidelines of the Committee on Hearing and Equilibrium of the American Academy of Otolaryngology-Head and Neck Surgery Foundation, preoperative hearing levels of the 44 patients were as follows: Class A, 19 patients; Class B, 17; and Class C, 8. The surgical technique for curative tumor removal with preservation of hearing and facial function included sharp dissection and debulking of the tumor, reconstruction of the internal auditory canal, and wide removal of internal auditory canal dura. Results. For all patients, tumors were totally removed without incidence of facial palsy, death, or other complications. Total tumor removal was confirmed by the first postoperative Gd-enhanced MRI performed 12 months after surgery. Postoperative hearing levels were Class A, 5 patients; Class B, 21; Class C, 11; and Class D, 7. Postoperatively, serviceable (Class A, B, or C) and useful (Class A or B) levels of hearing were preserved for 84% and 72% of patients, respectively. Better preoperative hearing resulted in higher rates of postoperative hearing preservation (p = 0.01); preservation rates were 95% among patients with preoperative Class A hearing, 88% among Class B, and 50% among Class C. Reliable monitoring was more frequently provided by CNAPs than by ABRs (66% vs 32%, p < 0.01), and consistently reliable auditory monitoring was significantly associated with better rates of preservation of useful hearing. Long-term follow-up by MRI with Gd administration (81 ± 43 months [range 5-181 months]; median 7 years) showed no tumor recurrence, and although the preserved hearing declined minimally over the long-term postoperative follow-up period (from 39 ± 15 dB to 45 ± 11 dB in 5.1 ± 3.1 years), 80% of useful hearing and 100% of serviceable hearing remained at the same level. Conclusions. As a result of a surgical technique that involved sharp dissection and internal auditory canal reconstruction with intraoperative auditory monitoring, retrosigmoid removal of small ANs can lead to successful curative tumor removal without long-term recurrence and with excellent functional outcome. Thus, the authors suggest that tumor removal should be the first-line management strategy for younger patients with small ANs and preserved hearing. ©AANS, 2014. Source

Xiao Y.,Capital Normal University | Niu G.,Texas AgriLife Research Center | Kozai T.,Chiba University
Plant Cell, Tissue and Organ Culture | Year: 2011

Research has revealed that most chlorophyllous explants/plants in vitro have the ability to grow photoautotrophically (without sugar in the culture medium), and that the low or negative net photosynthetic rate of plants in vitro is not due to poor photosynthetic ability, but to the low CO2 concentration in the air-tight culture vessel during the photoperiod. Moreover, numerous studies have been conducted on improving the in vitro environment and investigating its effects on growth and development of cultures/plantlets on nearly 50 species since the concept of photoautotrophic micropropagation was developed more than two decades ago. These studies indicate that the photoautotrophic growth in vitro of many plant species can be significantly promoted by increasing the CO2 concentration and light intensity in the vessel, by decreasing the relative humidity in the vessel, and by using a fibrous or porous supporting material with high air porosity instead of gelling agents such as agar. This paper reviews the development and characteristics of photoautotrophic micropropagation systems and the effects of environmental conditions on the growth and development of the plantlets. The commercial applications and the perspective of photoautotrophic micropropagation systems are discussed. © 2010 Springer Science+Business Media B.V. Source

Hamada Y.,Chiba University
Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry | Year: 2011

This review describes the development of a new class of chiral secondary phosphine oxide preligands: Amino acid-derived P-chiral diaminophosphine oxides, DIAPHOXs, and their application to several transition metal-catalyzed asymmetric reactions. The Pd-DJAPHOX catalyst system was successfully applied to enantioselective construction of quaternary stereocenters through Pd-catalyzed asymmetric allylic alkylation with β-keto esters as prochiral nucleophiles, asymmetric allylic substitutions with nitromethane, asymmetric allylic amination with various substrates, and enantioselective synthesis of axially chiral allenes. Ir-catalyzed asymmetric allylic amination and alkylation of terminal allylic carbonates were also examined using structurally optimized DIAPHOX preligands, and the corresponding branched products were obtained in a highly regio- and enantioselective manner. Furthermore, the developed processes were successfully applied to the enantioselective synthesis of biologically active compounds. Source

Ohba T.,Chiba University | Kaneko K.,Shinshu University
Langmuir | Year: 2011

Water adsorption hysteresis is one of the most important phenomena observed during the interaction of water with hydrophobic surfaces. Adsorption hysteresis in micropores has strong relevance to the structure of adsorbed water. We used three typical models (cluster, monolayer, and uniform distribution structure models) to determine the structure of the water molecules adsorbed in hydrophobic slit-shaped carbon micropores. In each model, stabilization energy profiles were calculated for various fractional fillings by using the interaction potential theory. Simultaneously, molecular dynamics (MD) simulations of water adsorbed in the micropore of 1.1 nm pore width, which shows significant adsorption hysteresis, were performed to determine the kinetics of the observed structural transformations. The transformations between monolayer and cluster were slow, that is, kinetically forbidden at the fractional filling of 0.2 and 0.6, whereas the cluster-uniform distribution structure and uniform distribution structure-monolayer transformations were kinetically allowed. The kinetically forbidden transformation resulted in the occurrence of metastable structure of adsorbed water and was responsible for the observed adsorption hysteresis. © 2011 American Chemical Society. Source

Hirano S.,Chiba University | Hirano S.,Japan National Institute of Radiological Sciences | Shinotoh H.,Japan National Institute of Radiological Sciences | Eidelberg D.,Feinstein Institute for Medical Research | Eidelberg D.,New York University
Journal of Neurology, Neurosurgery and Psychiatry | Year: 2012

Multiple factors are involved in the development of cognitive impairment in Parkinson's disease (PD) and related disorders. Notably, several underlying factors, such as monoaminergic dysfunction, Lewy body pathology, Alzheimer disease-like pathology and cerebrovascular disease are implied in the PD pathophysiology of cognitive impairment. The mesocortical dopaminergic system is associated with executive functions which are frequently affected in PD and are influenced by local levodopa concentration, dopamine metabolism and baseline performance status. The ventral striatum and frontal cortex are associated with impulse control disorders reported in PD patients treated with dopamine replacement therapy. Cholinergic impairment in PD plays a cardinal role in the development of dementia. Acetylcholinesterase positron emission tomography demonstrates that posterior brain areas are related to cognitive decline in PD patients. Amyloid radiotracer illustrates that patients with PD with severe cognitive impairment were prone to accompanied cortical amyloid deposition. Metabolism/perfusion change associated with cognitive impairment in PD, so-called PD related cognitive pattern, is characterised by reduced frontoparietal activity and is an effective way to differentiate and monitor cognitive function of individual PD patients. Cognitive impairment in PD cannot be explained by a single mechanism and is entangled by multiple factors. Imaging studies can unravel each pathological domain, further shed light on the interrelation between different pathomechanisms, not only in PD but also in other dementia related disorders, and thereby integrate its interpretation to apply to therapeutics in individual patients. Source

Tsuchida E.,Japan National Institute of Advanced Industrial Science and Technology | Choe Y.-K.,Japan National Institute of Advanced Industrial Science and Technology | Ohkubo T.,Chiba University
Physical Chemistry Chemical Physics | Year: 2015

We present the current status of the finite-element method for large-scale atomistic simulations based on the density-functional theory. After a brief overview of our formulation, we describe recent developments, including the optimal choice of adaptive coordinates, an efficient implementation of the ground-state calculations, and a remedy for the eggbox effect. As a new application of our formulation, we present ab initio molecular dynamics simulations on sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (SPPBP), which is a typical example of polymer electrolyte membranes for fuel cells. © The Royal Society of Chemistry 2015. Source

Nakamoto T.,Chiba University
Nihon Kikai Gakkai Ronbunshu, C Hen/Transactions of the Japan Society of Mechanical Engineers, Part C | Year: 2013

The purpose of this research work is to fabricate small pipes consisting of boron carbide. The characteristics of boron carbide are hard and anti-corrosion. However, it is difficult to sinter the material and to obtain small pipes. Therefore, a new method is developed to fabricate pipes of boron carbide in this paper. At first, graphite powder is mixed with boron powder. And the surface of mixed powder is irradiated by a laser beam. And then, the powder is evaporated at the central portion of the laser beam. Boron carbide is produced around the central portion by the chemical reaction between the graphite powder and boron powder. Then, a small pipe consisting of boron carbide is obtained. The outer, inner diameter and length of the pipes are measured for different irradiating conditions of laser beam. The boron carbide is detected by XRD in the pipes. It is deduced that the concentration of boron carbide at the inner surface of the pipes is more than that at the other portions. Connected two or three pipes are fabricated by this method. © 2013 The Japan Society of Mechanical Engineers. Source

Shimokawa M.,Chiba University
Journal of the Physical Society of Japan | Year: 2012

A fractal pattern was observed on the surface of a lower-density solution owing to gravitational instability, when a droplet of a higher-density solution was placed on the lower-density solution surface. The relationship between the fractal pattern and the vertical flow was studied in containers of different configurations and sizes in order to understand the formation dynamics. It was found that fractal patterns of similar structure emerge independent of the configuration. The transition from a fractal pattern to a cell pattern occurs at r ≈ h in experiments involving the use of various sizes of containers, where r and h are the radius of the container and the depth of the lower-density solution, respectively. The vertical flow for fractal patterns is different from that for cell patterns and has an axisymmetric structure. These results indicate that an axisymmetric flow is necessary for the formation of a fractal pattern. © 2012 The Physical Society of Japan. Source

2,6-Dimethyl-9-Aryl-9-phosphabicyclo[3.3.1]nonanes (9-PBN and 9-NapBN) and the chiral diaminophosphine oxides (DIAPHOXs) derived from aspartic acid have been introduced as useful ligands and preligands, respectively, for transition metal-catalyzed asymmetric synthesis. anti-Selective asymmetric hydrogenation of α-amino-β-ketoesters using Ru-, Rh-, Ir-, and Ni-catalysts through dynamic kinetic resolution have been developed for the first time, producing efficiently important anti β-hydroxy-α-amino acids. The total synthesis of several biologically active natural products was achieved by use of the transition metal-catalyzed reaction using DIAPHOX, anti-selective asymmetric hydrogenation, and reactions developed by us. Synthesis of tangutorine, an antitumor indole alkaloid, has been enantioselectively achieved for the first time. Enantioselective synthesis of a martinelline chiral core was accomplished using the asymmetric tandem Michael-Aldol reaction as a key step developed by us. This synthesis represents the formal total synthesis of martinelline and martinellic acid. Papuamide B was synthesized through the elucidation of unknown stereostructures by using the anti-selective asymmetric hydrogenation and reactions developed by us. © 2012 The Pharmaceutical Society of Japan. Source

Fabry disease is an X-linked lysosomal disorder caused by a deficiency in lysosomal glycohy- drolase α-galactosidase A. This defect results in the accumulation of glycosphingolipids in various organ systems. Lipid deposits occur preferentially in vascular endothelial and smooth muscle cells, leading to vascular dysfunction, which results in tissue ischemia and vessel occlusion. Clinical symptoms are divided into two categories: Early symptoms and late complications. Early symptoms include acroparesthesia, bouts of pain in the hands or feet, hypohidrosis, angiokeratoma, and gastrointestinal complications, which begin in the early childhood of patients with Fabry disease. Late complications include renal and cardiac dysfunction, and cerebral infarction, which determine morbidity and mortality after age 30 years. Enzyme replacement therapy (ERT) using recombinant human ar-galactosidase A has recently developed, and has been shown to improve prognosis of patients with Fabry disease. Recent reports investigating long-term outcomes with ERT have shown that early initiation before the development of irreversible organ failure is particularly effective. Diagnosis at the early stage of the disorder and the early initiation of ERT alleviate symptoms and prevent late complications. The disorder should be widely recognized to improve patients' outcome. Source

Yamashita T.,Sapporo Medical University | Takahashi K.,Chiba University | Yonenobu K.,Jikei Institute | Kikuchi S.-I.,Fukushima Medical University
Journal of Orthopaedic Science | Year: 2014

Background: The incidence and characteristics of neuropathic pain associated with spinal disorders have not yet been fully clarified. The purpose of this study was to investigate the prevalence of neuropathic pain and the degree of deterioration of quality of life (QOL) in patients with chronic pain associated with spinal disorders who visited orthopedic outpatient clinics. Methods: This cross-sectional study was conducted in 1,857 patients recruited from 137 medical institutions nationwide. Participants were men and women aged 20-79 years with a history of spine-related pain for at least 3 months and a visual analog scale (VAS) score of at least 30 in the previous week. Patients were screened using a neuropathic pain screening questionnaire. The degree of QOL deterioration and its correlation with the presence of neuropathic pain were assessed using the Short Form Health Survey with 36 questions (SF-36). Results: Overall prevalence of neuropathic pain was 53.3%. It was relatively high in patients with cervical spondylotic myelopathy (77.3%) and ligament ossification (75.7%) and relatively low in those with low back pain (29.4%) and spondylolysis (40.4%). Only 56.9% of patients with radiculopathy were diagnosed with neuropathic pain. Logistic regression analysis identified several risk factors, including advanced age, severe pain, disease duration of at least 6 months, and cervical lesions. In QOL assessment, physical functioning, role-physical, role-emotional, and social functioning were severely affected, and this trend was more pronounced in patients who were more likely to have neuropathic pain. Conclusions: The frequency of neuropathic pain tended to be higher in patients with diseases associated with spinal cord damage and lower in patients with diseases that primarily manifested as somatic pain. A bias toward allodynia symptoms in the screening questionnaire may have resulted in the failure to diagnose neuropathic pain in some patients with radiculopathy. Poor QOL, primarily from the aspect of physical functioning, was demonstrated in patients with neuropathic pain associated with spinal disorders. © The Japanese Orthopaedic Association 2013. Source

Bagrets A.,Karlsruhe Institute of Technology | Schmaus S.,Karlsruhe Institute of Technology | Schmaus S.,Max Planck Institute for Solid State Research | Jaafar A.,CNRS Institute of Genetics and of Molecular and Cellular Biology | And 6 more authors.
Nano Letters | Year: 2012

The magnetoresistance of a hydrogen-phthalocyanine molecule placed on an antiferromagnetic Mn(001) surface and contacted by a ferromagnetic Fe electrode is investigated using density functional theory based transport calculations and low-temperature scanning tunneling microscopy. A large and negative magnetoresistance ratio of ∼50% is observed in combination with a high conductance. The effect originates from a lowest unoccupied molecular orbital (LUMO) doublet placed almost in resonance with the Fermi energy. As a consequence, irrespective of the mutual alignment of magnetizations, electron transport is always dominated by resonant transmission of Mn-majority charge carries going through LUMO levels. © 2012 American Chemical Society. Source

Akimoto A.,Nara Womens University | Hirano Y.M.,Chiba University | Sakai A.,Nara Womens University | Yusa Y.,Nara Womens University
Marine Biology | Year: 2014

Sacoglossans use chloroplasts taken from algal food for photosynthesis (kleptoplasty), but the adaptive significance of this phenomenon remains unclear. Two con-generic sacoglossans (Elysia trisinuata and E. atroviridis) were collected in 2009-2011 from Shirahama (33.69°N, 135.34°E) and Mukaishima (34.37°N, 133.22°E), Japan, respectively. They were individually maintained for 16 days under four experimental conditions (combination of light/dark and with/without food), and their survival rate and relative (=final/initial) weights were measured. Both light and food had positive effects on the survival in E. trisinuata, whereas no positive effects of light or food on survival were detected in E. atroviridis. Both light and food had positive effects on relative weights in both species, but light had smaller effects than food. A significant interaction term between light and food was detected in E. trisinuata (but not in E. atroviridis) in that only the presence of both resulted in weight gains. This result suggests that E. trisinuata can obtain sufficient additional energy from photosynthesis for sustaining growth when fresh chloroplasts are continuously supplied from algal food. In addition, fluorescence yield measurements showed that unfed individuals of both E. trisinuata and E. atroviridis lost photosynthetic activity soon (<4 and 4-8 days, respectively). In conclusion, photosynthesis may function to obtain supplementary nutrition for sustaining growth when food is available in sacoglossans with short-term functional kleptoplasty. © 2014 Springer-Verlag Berlin Heidelberg. Source

Iwadate Y.,Chiba University
Oncology Letters | Year: 2016

Epithelial-mesenchymal transition (EMT) is a reversible biological process that occurs in epithelial cells. EMT ultimately leads to the acquisition of a mesenchymal phenotype, characterized by increased cell motility and resistance to genotoxic agents. These processes mostly overlap with the acquirement of stem cell properties in differentiated tumor cells. With regard to gliomas, the clinical picture is heterogeneous, even within the same grades and histological categories of the disease. Furthermore, the areas of invasion and responses to radiochemotherapy are markedly different among cases, and occasionally even in the same patient. Such phenotypic diversity in glioma tissues may be caused by various microenvironmental factors, as well as intrinsic genetic alterations. The current review focuses on the EMT-inducing factors that are present in gliomas; these typically vary from those observed in epithelial cancers, as no basement membrane is present. Furthermore, the most important cell-cell contact factor, E-cadherin, is rarely expressed in gliomas. The microenvironment that induces EMT in gliomas is characterized by hypoxia and the enrichment of myeloid cells following stimulation by transforming growth factor-β. Antivascular endothelial growth factor therapy, including the use of bevacizumab, may be a suitable candidate to modulate the glioma microenvironment. © 2016, Spandidos Publications. All rights reserved. Source

Kishimoto W.,Chiba University
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2011

In a directed flow network we assign capacities on vertices as well as on edges. We consider a (δ, η)-balanced flow problem of single commodity case. A (δ, η)-balanced flow is defined as a flow such that the flow value at each edge is not more than δ·f and the flow value at each vertex is not more than η•f, where f is the total amount of the flow. Based on (δ, η)-balanced flow, the (δ, η)-capacity is defined for a mixed cut in a network. A mixed cut in a network is a set of edges and vertices removal of those separates the network. Then the max-flow min-cut theorem for this (δ, η)-balanced flow is proved for the single commodity case in a directed network. The theorem for (δ, η)-balanced flow is not easily to be proved by only applying the max-flow min-cut theorem of ordinary flows. Then we show a method for evaluating the maximum (δ, η)-balanced flow. The algorithm gives the maximum value of (δ,η)-balanced flow between s and t in N with at most |V|·|E| evaluations of maximum flow in a network, where V is the vertex set of N and E is the edge set of N, respectively. Each evaluations of the maximum flow is performed in N with altered capacities on edges and on vertices. We can apply all the results to undirected networks. © 2011 Springer-Verlag. Source

Nakayama T.,Chiba University
Advances in Experimental Medicine and Biology | Year: 2010

Abstract Schnurri (Shn) is a large zinc-finger containing protein, which plays a critical role in cell growth, signal transduction and lymphocyte development. There are three orthologues (Shn-1, Shn-2 and Shn-3) in vertebrates. In Shn-2-deficient mice, the activation of NF-κB in CD4 T cells is upregulated and their ability to differentiate into Th2 cells is enhanced in part through the increased expression of GATA3. Shn-2 is found to compete with p50 NF-κB for binding to a consensus NF-κB motif and inhibit the NF-κB-driven promoter activity. In addition, Th2-driven allergic airway inflammation was enhanced in Shn-2-deficient mice. Therefore, Shn-2 appears to negatively control the differentiation of Th2 cells and Th2 responses through the repression of NF-κB function. Memory Th1/Th2 cells are not properly generated from Shn-2-deficient effector Th1/Th2 cells. The expression levels of CD69 and the number of apoptotic cells are selectively increased in Shn-2-deficient Th1/Th2 cells when they are transferred into syngeneic host animals, in which memory Th1/Th2 cells are generated within a month. In addition, an increased susceptibility to apoptotic cell death is also observed in vitro accompanied with the increased expression of FasL, one of the NF-κB-dependent genes. Th2 effector cells overexpressing the p65 subunit of NF-κB demonstrate a decreased cell survival particularly in the lymph node. These results indicate that Shn-2-mediated repression of NF-κB is required for cell survival and the successful generation of memory Th1/Th2 cells. This may point to the possibility that after antigen clearance the recovery of the quiescent state in effector Th cells is required for the generation of memory Th cells. A repressor molecule Shn-2 plays an important role in this process. © 2010 Landes Bioscience and Springer Science +Business Media. Source

Carbon nanotubes and graphene are among the major nanomaterials in nanoscience and technology. Despite having π electrons, these nanocarbon allotropes have been simply considered as neutral in classical calculations. In this study, the effects of partial charges on graphene and curved interfaces on molecular adsorption were investigated using Monte Carlo simulations of N2 and NaCl aqueous solutions on graphene and carbon nanotubes. The simulated N2 adsorption behavior and adsorption potential on partially charged and non-charged graphene coincided with each other. The adsorption potentials suggested that partially charged graphene attracted Na ions and repelled Cl ions. However, those tendencies were not present in NaCl aqueous solutions on graphene. Conversely, in partially charged carbon nanotube models, a preference for Na ions and repulsion of Cl ions in the internal nanospaces were observed in the adsorption potentials using Monte Carlo simulations. Curved interfaces in the internal nanospaces of carbon nanotubes enhanced these properties, suggesting significant electrostatic interactions in a curved π-conjugated system. © 2016 the Owner Societies. Source

Saito Y.,Chiba University
Atherosclerosis Supplements | Year: 2011

Compared to other statins, pitavastatin is a highly potent 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase inhibitor and an efficient hepatocyte low-density lipoprotein-cholesterol (LDL-C) receptor inducer. Its characteristic structure (heptenoate as the basic structure, a core quinoline ring and side chains that include fluorophenyl and cyclopropyl moieties) provides improved pharmacokinetics and significant LDL-C-lowering efficacy at low doses. Unlike other statins, the cyclopropyl group on the pitavastatin molecule appears to divert the drug away from metabolism by cytochrome P450 (CYP) 3 A4 and allows only a small degree of clinically insignificant metabolism by CYP2C9. As a result, pitavastatin is minimally metabolized; most of the bioavailable fraction of an oral dose is excreted unchanged in the bile and is reabsorbed by the small intestine ready for enterohepatic recirculation. This process probably accounts for pitavastatin's increased bioavailability relative to most other statins and contributes to its prolonged duration of action. In addition to its potent LDL-C-lowering efficacy, a number of pleiotropic benefits that might lead to a reduction in residual risk have been suggested in vitro. These include beneficial effects on endothelial function, stabilisation of the coronary plaque, anti-inflammatory effects and anti-oxidation. With regard to the clinical safety and efficacy of pitavastatin, the Phase IV Collaborative study of Hypercholesterolemia drug Intervention and their Benefits for Atherosclerosis prevention (CHIBA study) showed similar changes in lipid profile with pitavastatin and atorvastatin in Japanese patients with hypercholesterolemia. However, a subgroup analysis of the CHIBA study showed that pitavastatin produced more significant changes from baseline in LDL-C, TG, and HDL-C in patients with hypercholesterolemia and metabolic syndrome. The clinical usefulness of pitavastatin has been further demonstrated in a number of Japanese patient groups with hypercholesterolemia, including those with insulin resistance, low levels of high-density lipoprotein-cholesterol (HDL-C), high levels of C-reactive protein, and chronic kidney disease. Finally, the Japan Assessment of Pitavastatin and AtorvastatiN in Acute Coronary Syndrome (JAPAN-ACS) study showed that pitavastatin induces plaque regression in patients with ACS, which suggests potential benefits for pitavastatin in reducing CV risk. © 2011 Elsevier Ireland Ltd. Source

Imamura T.,Tokyo University of Science | Sasamoto T.,Chiba University
Physical Review Letters | Year: 2012

We obtain the first exact solution for the stationary one-dimensional Kardar-Parisi-Zhang equation. A formula for the distribution of the height is given in terms of a Fredholm determinant, which is valid for any finite time t. The expression is explicit and compact enough so that it can be evaluated numerically. Furthermore, by extending the same scheme, we find an exact formula for the stationary two-point correlation function. © 2012 American Physical Society. Source

Albayrak Y.,KIrklareli State Hospital | Hashimoto K.,Chiba University
Primary Care Companion to the Journal of Clinical Psychiatry | Year: 2012

Objective: Tardive dyskinesia (TD) is characterized by involuntary, repetitive, purposeless movements that can affect different parts of the body. Tardive dyskinesia is a well-known side effect of conventional antipsychotics and commonly occurs after several years of treatment. The effective treatment of TD is unclear. Recently, the sigma-1 receptor agonist fluvoxamine was reported to be beneficial for hyperkinetic movement disorders. Method: We report 5 cases with postpsychotic depressive disorder of schizophrenia and TD. All patients were given fluvoxamine 100 mg/d, and after the second week the dosage of fluvoxamine was increased to 200 mg/d. At the fourth week, patients were assessed in terms of TD and postpsychotic depressive disorder of schizophrenia. Results: Fluvoxamine was found to be beneficial for TD and postpsychotic depressive disorder of schizophrenia in all patients by the fourth week. Conclusions: Recently, the sigma-1 receptor agonist fluvoxamine has been considered beneficial for various neuropsychiatric disorders. However, data about the effects of fluvoxamine on hyperkinetic movement disorders are limited. In this report, we attempted to demonstrate the beneficial effects of fluvoxamine on TD, and we suggest that the mechanism of action might be due to sigma-1 agonism. Further detailed, double-blind studies should clarify the potential use of fluvoxamine in the treatment of hyperkinetic movement disorders. © 2012 Physicians Postgraduate Press, Inc. Source

Yoshida H.,Chiba University
Journal of Physical Chemistry C | Year: 2015

When a thin layer of bathocuproine (BCP) is inserted between the metal electrode and the organic layer of the organic semiconductor device, the electron injection/collection efficiency at the interface is significantly improved. However, the mechanism of electron transport through the BCP layer has not been clarified yet. In this study, we directly observed the unoccupied electronic states of the Ag/BCP interface using low-energy inverse photoemission spectroscopy. The result shows that Ag strongly interacts with the BCP molecule and the lowest unoccupied molecular orbital (LUMO) level of the Ag-BCP complex aligns with the Fermi level, indicating that the electron transport occurs through the LUMO level of the complex. With the aid of DFT calculation, we identify the reaction product. © 2015 American Chemical Society. Source

Reflectance loss of p-polarized infrared light at longitudinal optical (LO) phonon energies has been reported by Berreman. The origin of this loss has been discussed in view of the absorption by electric dipole moment by the polarization charges at the interfaces and propagation of interface polaritons. However, the existence of the absorption effect is not clear. In this issue, we take an example of GaN films with large polarization charges, and distinguish the two effects on optical spectra by theoretical and experimental analysis. It is found for the first time that the absorption by electric dipoles at the resonant energy with the LO phonon or LO phonon-plasmon coupling (LOPC) mode is identified separately from the interface polariton effect by varying the wavenumber component parallel to the interfaces by attenuated total reflectance analysis. We construct a theoretical expression of the pseudo-dielectric function of thin films around the LO phonon or LOPC mode energies, and show the quantitative proof of the existence of the absorption effect in the experimental spectra. © 2012 American Institute of Physics. Source

Ding B.,Shanghai JiaoTong University | Zhang Z.,Shanghai JiaoTong University | Liu Y.,Shanghai JiaoTong University | Sugiya M.,Nippon Chemical Industrial Co. | And 3 more authors.
Organic Letters | Year: 2013

A pincer-Pd complex was utilized in the chemoselective transfer hydrogenation of α,β-unsaturated ketones using n-BuOH as a hydrogen source and solvent. Good to excellent yields were obtained for various substrates even with reducible groups. Based on deuterium-labeling experiments, the reaction mechanism is proposed to occur via a pincer-Pd-hydride intermediate. © 2013 American Chemical Society. Source

Kuwabara S.,Chiba University
Cochrane database of systematic reviews (Online) | Year: 2012

POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes) syndrome is a rare cause of demyelinating and axonal mixed neuropathy with monoclonal plasma cell proliferative disorder and multiorgan involvement. The pathogenesis of POEMS syndrome is not well understood, but overproduction of vascular endothelial growth factor (VEGF), probably secreted by plasmacytomas, is likely to be responsible for most of the characteristic symptoms. POEMS syndrome is a potentially fatal disease, and patients' quality of life deteriorates because of progressive neuropathy, massive pleural effusion or ascites, or thromboembolic events. There is a need for efficacious therapy to improve prognosis. This is the first update of a review first published in 2008. To assess the effects of treatment for POEMS syndrome. We searched the Cochrane Neuromuscular Disease Group Specialized Register (23 February 2012), CENTRAL (2012, Issue 2), MEDLINE (January 1966 to February 2012), EMBASE (January 1980 to February 2012) and CINAHL Plus (January 1937 to February 2012) for all papers on POEMS syndrome We sought all randomized and quasi-randomized controlled trials, and non-randomized controlled studies. Since we discovered no such clinical trials, we assessed and summarized all retrospective case series including five or more patients in the 'Discussion' section. Two review authors independently reviewed and extracted details of all potentially relevant trials with any treatment for POEMS syndrome. We then collated and summarized information on the outcome. We found no randomized or non-randomized prospective controlled trials of treatment for POEMS syndrome. We summarized the results of retrospective case series containing five or more patients in the 'Discussion' section. There are no randomized or quasi-randomized controlled clinical trials of treatment for POEMS syndrome on which to base practice. Source

Ueta T.,Chiba University
IOP Conference Series: Materials Science and Engineering | Year: 2014

Photon-phonon interaction on the analogy of electron-phonon interaction is considered in one-dimensional photonic crystal. When lattice vibration is artificially introduced to the photonic crystal, a governing equation of electromagnetic field is derived. A simple model is numerically analysed and the following novel phenomena are found out. The lattice vibration generates the light of frequency which added the integral multiple of the vibration frequency to that of the incident wave and also amplifies the incident wave resonantly. On a resonance, the amplification factor increases very rapidly with the number of layers increases. Resonance frequencies change with the phases of lattice vibration. The amplification phenomenon is analytically discussed for low frequency of the lattice vibration. © 2010 IOP Publishing Ltd. Source

Hashimoto K.,Chiba University
Expert Opinion on Therapeutic Targets | Year: 2014

Introduction: Abnormalities in glutamatergic neurotransmission mediated by N-methyl-d-aspartate (NMDA) are implicated in the pathophysiology of schizophrenia, although the precise mechanisms are unknown. Areas covered: The author examines the role of the NMDA receptor in schizophrenia, focusing on results from preclinical and clinical studies that support the NMDA receptor hypothesis of schizophrenia. The author first reviewed papers detailing alterations in the levels of endogenous substances such as glutamine, glutamate, d-serine, l-serine, kynurenic acid and glutathione (GSH), all of which can affect NMDA receptor function. Next, the author reviewed clinical findings for glycine, d-serine, d-cycloserine, d-amino acid oxidase inhibitors (e.g., sodium benzoate) and glycine transporter-1 inhibitors (e.g., sarcosine, bitopertin), as potential therapeutic drugs. In addition, the author outlined how oxidative stress associated with decreased levels of the endogenous antioxidant GSH may play a role in the pathophysiology of schizophrenia. Finally, the author reviewed N-acetylcysteine (NAC), a precursor of GSH and an activator of the cystine-glutamate antiporter, as a potential therapeutic drug. Expert opinion: Given the NMDA receptor hypothesis of schizophrenia, the glycine modulatory site on NMDA receptors is the most attractive therapeutic target for this disease. In addition, both the kynurenine pathway and cystine-glutamate antiporter represent credible potential therapeutic targets for schizophrenia. © 2014 Informa UK, Ltd. Source

Nakaya H.,Chiba University
Journal of Cardiovascular Pharmacology and Therapeutics | Year: 2014

The sarcolemmal adenosine triphosphate (ATP)-sensitive K+ (sarcKATP) channel in the heart is a hetero-octamer comprising the pore-forming subunit Kir6.2 and the regulatory subunit sulfonylurea receptor SUR2A. By functional analysis of genetically engineered mice lacking sarcKATP channels, the pathophysiological roles of the K+ channel in the heart have been extensively evaluated. Although mitochondrial KATP (mitoKATP) channel is proposed to be an important effector for the protection of ischemic myocardium and the inhibition of ischemia/reperfusion-induced ventricular arrhythmias, the molecular identity of mitoKATP channel has not been established. Although selective sarcKATP-channel blockers can prevent ischemia/reperfusion-induced ventricular arrhythmias by inhibiting the action potential shortening in the acute phase, the drugs may aggravate the ischemic damages due to intracellular Ca2+ overload. The sarcKATP channel is also mandatory for optimal adaptation to hemodynamic stress such as sympathetic activation. Dysfunction of mutated sarcKATP channels in atrial cells may lead to electrical instability and atrial fibrillation. Recently, it has been proposed that the gain-of-function mutation of cardiac Kir6.1 channel can be a pathogenic substrate for J wave syndromes, a cause of idiopathic ventricular fibrillation as early repolarization syndrome or Brugada syndrome, whereas loss of function of the channel mutations can underlie sudden infant death syndrome. However, precise role of Kir6.1 channels in cardiac cells remains to be defined and further study may be needed to clarify the role of Kir6.1 channel in the heart. © The Author(s) 2013. Source

Self-incompatibility (SI) is a major obstacle for stable fruit production in fruit trees of Rosaceae. SI of Rosaceae is controlled by the S locus on which at least two genes, pistil S and pollen S, are located. The product of the pistil S gene is a polymorphic and extracellular ribonuclease, called S-RNase, while that of the pollen S gene is a protein containing the F-box motif, SFB (S haplotype-specific F-box protein)/SFBB (S locus F-box brothers). Recent studies suggested that SI of Rosaceae includes two different systems, i.e., Prunus of tribe Amygdaleae exhibits a self-recognition system in which its SFB recognizes self-S-RNase, while tribe Pyreae (Pyrus and Malus) shows a non-self-recognition system in which many SFBB proteins are involved in SI, each recognizing subset of non-self-S-RNases. Further biochemical and biological characterization of the S locus genes, as well as other genes required for SI not located at the S locus, will help our understanding of the molecular mechanisms, origin, and evolution of SI of Rosaceae, and may provide the basis for breeding of self-compatible fruit tree cultivars. © 2016, Japanese Society of Breeding. All rights reserved. Source

BACKGROUND: Baseline coronary artery diameter and coronary artery dilation response to nitrate are associated with coronary vasoreactivity. OBJECTIVES: The present study investigated the predictive value of coronary artery tone for a positive intracoronary acetylcholine (ACh) provocation test. METHODS: A total of 197 patients who underwent an ACh provocation test in the right coronary artery were included. A positive ACh provocation test was defined as transient total or subtotal occlusion of a coronary artery with signs/symptoms of myocardial ischemia. The segment, from the ostium to the bifurcation, of the right coronary artery was analyzed quantitatively. Coronary artery dilation response to isosorbide dinitrate (ISDN) was defined as the mean lumen diameter after an intracoronary injection of ISDN divided by the diameter before administration of ACh (i.e. baseline coronary artery diameter). RESULTS: After the administration of ACh, 49 patients (24.9%) had a positive ACh provocation test. Smaller baseline right coronary artery diameter (2.35±0.45 vs. 2.73±0.48 mm, P<0.001) and greater right coronary artery dilation response to ISDN (1.34±0.12 vs. 1.15±0.11, P<0.001) were observed in patients with a positive ACh provocation test. The receiver operating characteristic curve for baseline coronary artery diameter poorly predicted the occurrence of a positive ACh provocation test (area under the curve 0.71). The predictive values of dilation response of the right coronary artery to ISDN for the occurrence of a positive ACh provocation test (area under the curve 0.87) was significantly better compared with that of baseline right coronary artery diameter (P<0.001). CONCLUSION: Coronary artery dilation response to nitrate is a more accurate predictor of a positive intracoronary ACh provocation test compared with baseline coronary artery diameter. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved. Source

A zeolitic adsorbent was synthesized from waste green tuff stone cake by hydrothermal treatment, and its adsorption of silver ions from aqueous solution was examined for application in silver ion removal from polluted industrial waters and as a bactericide. The waste cake was composed mainly of SiO2 and Al2O3 in the form of silicate and aluminosilicate minerals, such as quartz, anorthite, muscovite and clinochlore. The cake was treated with 0-10 M NaOH solution at 80, 120 and 160 °C for 24 h, and analcime, hydroxysodalite and hydroxycancrinite were synthesized. A product with high silver adsorption ability, including analcime, was obtained in 4 M NaOH solution at 160 °C. The concentrations of Si and Al in the solution during the reaction in 4 M NaOH solution at 160 °C explain the synthesis of analcime zeolite phase due to the dissolution of quartz and anorthite in the cake, and Ag adsorption of the product depends on analcime zeolite crystals in the product. The optimal pH for silver adsorption for the product was found to be around 5. The equilibrium silver adsorption capacity was measured and extrapolated using the Langmuir and Freundlich isotherm models, and experimental data were found to fit the Langmuir model. The calculated maximum adsorption capacity of 1.10 mmol/g shows that this product is suitable for silver uptake from aqueous media. Adsorption kinetics was tested for pseudo-first- and -second-order reactions, and the rate constants of adsorption for these kinetic models were calculated. Adsorption experiments demonstrated that the adsorption process corresponds to a pseudo-second- rather than -first-order kinetics model. With decreasing aqueous solution temperature, the adsorption kinetics become slower and the amount of silver ion adsorbed increases. The thermodynamic values, δG°, δH° and δS°, indicated that adsorption was an exothermic and spontaneous process. © 2016 Elsevier Inc. Source

Ishihara A.,Chiba University
Nuclear Physics B - Proceedings Supplements | Year: 2013

We report on a search for ultra-high energy neutrinos with energy greater than 106 GeV using the data taken with the IceCube detector at the South Pole. The data was collected between June 2010 and May 2011 when 90% of the IceCube detector was in operation and from May 2011 to May 2012 which corresponds to the first physics run with the fully completed IceCube detector. Two signal neutrino candidate events are observed in the sample of 670.1 days of livetime over expected background rates of 0.06 events. These events are consistent with the cascade-like events induced by νe charged current or νe,μ,τ neutral current interaction within the IceCube detector volume. Preliminary p-values for a background-only hypothesis are 1.6×10-3(2.9σ) without a prompt atmospheric neutrino contribution and 1.5×10-2(2.2σ) with a default perturbative QCD-based prompt neutrino contribution. © 2013 Elsevier B.V. Source