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41.
l‐Citrulline Supplementation‐Increased Skeletal Muscle PGC‐1α Expression Is Associated with Exercise Performance and Increased Skeletal Muscle Weight 下载免费PDF全文
Scope
l ‐citrulline has recently been reported as a more effective supplement for promoting intracellular nitric oxide (NO) production compared to l ‐arginine. Here, the effect of l ‐citrulline on skeletal muscle and its influence on exercise performance were investigated. The underlying mechanism of its effect, specifically on the expression of skeletal muscle peroxisome proliferator‐activated receptor‐gamma coactivator‐1α (PGC‐1α), was also elucidated.Methods and results
Six‐week‐old ICR mice were orally supplemented with l ‐citrulline (250 mg kg?1) daily, and their performance in weight‐loaded swimming exercise every other day for 15 days, was evaluated. In addition, mice muscles were weighed and evaluated for the expression of PGC‐1α and PGC‐1α‐regulated genes. Mice orally supplemented with l ‐citrulline had significantly higher gastrocnemius and biceps femoris muscle mass. Although not statistically significant, l ‐citrulline prolonged the swimming time to exhaustion. PGC‐1α upregulation was associated with vascular endothelial growth factor α (VEGFα) and insulin‐like growth factor 1 (IGF‐1) upregulation. VEGFα and IGF‐1 are important for angiogenesis and muscle growth, respectively, and are regulated by PGC‐1α. Treatment with NG‐nitro‐l ‐arginine methyl ester hydrochloride (l ‐NAME), a nitric oxide synthesis inhibitor, suppressed the l ‐citrulline‐induced PGC‐1α upregulation in vitro.Conclusion
Supplementation with l ‐citrulline upregulates skeletal muscle PGC‐1α levels resulting in higher skeletal muscle weight that improves time to exhaustion during exercise.42.
Akiya Kozawa Hidehiko Oho Mitsuru Sano Dorothy Brodd Ralph Brodd 《Journal of power sources》1999,80(1-2):12-16
Based on the previous success of adding ultra-fine carbon–PVA (polyvinyl alcohol) colloid solution to restore performance of weak batteries, a large scale test programme of practical batteries including those used in forklift, golf cart, taxi cab, truck and bus applications from 150 companies was carried out. More than 95% of the tested batteries exhibited excellent recovery in performance parameters including the specific gravity (S.G.), voltage and operation time (Ah capacity). The work reported here includes basic research studies to understand better the beneficial action of the carbon–PVA colloid additive. 相似文献
43.
Yasuo Takagi Mitsuru Onoda Tamotsu Toriyama Katsunori Kawasaki Toshiyuki Hattori 《亚洲传热研究》2013,42(5):444-458
This study investigated the characteristics of cell performance degradation, decline of component performance, and changes in the properties of membrane electrode assembly materials caused by repeated cold starts under a subzero condition of ?30 °C. It was made clear that functional decay appeared mainly at the cathode due to increased proton conductive impedance and reduction of reactivity of the electrode catalyst. Among the cathode components, an increase in proton conductive impedance in the cathode electrolyte was dominant. Furthermore, the application of ion chromatography and a newly developed proton‐induced gamma‐ray emission method to measure fluorine in the off‐gas drain revealed that decomposition of the electrolyte was dominant in the cathode catalyst layer. A decrease in fluorine in the cathode electrolyte measured by fluorine‐19 nuclear magnetic resonance confirmed this decomposition. A hypothesis is also presented concerning the cause of the performance degradation. © 2012 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20394 相似文献
44.
The authors have developed a software tool, MolSpace, to visualize massive molecular datasets. MolSpace can project a set of massive multivariate data onto a visual space (two- or three-dimensional space) by means of principal component analysis. MolSpace allows users not only to draw a scatter diagram of the data but also to display their two- or three-dimensional molecular structures as the objects in that space. With a probe (a molecular object) the user can navigate vast data spaces, thus facilitating understanding of the data structure. In addition, partial space searching is also available that is based on similarity searching techniques. It is possible to interrogate a three-dimensional structure of a chemical compound that corresponds to each object on the space in real time. The detail of the system is discussed with an illustrative example. 相似文献
45.
Hyungjin Kim Tomofumi Uto Takami Akagi Masanori Baba Mitsuru Akashi 《Advanced functional materials》2010,20(22):3925-3931
Size‐regulated amphiphilic poly(amino acid) nanoparticles (NPs) composed of poly(γ‐glutamic acid) (γ‐PGA) and the hydrophobic amino acid derivative, L ‐phenylalanine ethyl ester (Phe) are prepared to evaluate the effects of particle size on dendritic cell (DC) uptake of NPs and their immune stimulatory activities as delivery carriers and adjuvants. The size of the Phe‐conjugated γ‐PGA NPs (γ‐PGA–Phe NPs) is easily controlled by regulating the aggregated γ‐PGA–Phe numbers. Each of the differently sized γ‐PGA–Phe NPs could efficiently encapsulate ovalbumin (OVA), and the amount of encapsulated OVA per milligram of NPs is almost the same despite the differences in size. The DC uptake of small NPs is lower than for the larger NPs, but the effect of DC activation by NPs is high in the small sizes. The DC activation is significantly affected by the size of the NPs, which suggests that not only the uptake process of the NPs, but also the surface interactions between the NPs and DCs, is important for the induction of DC maturation. The precisely size‐controllable γ‐PGA–Phe NPs have significant potential as an antigen carrier and vaccine adjuvant. These results should provide guidelines for adjuvant design in the development of an effective vaccine. 相似文献
46.
Matsukawa T. Yoshida Y. Kanke M. Yamashita K. Shimada R. Nakayama T. 《Energy Conversion, IEEE Transaction on》1987,(2):262-268
A 215 MVA flywheel motor-generator is used for the toroidal field coil power supply system of the energy breakeven plasma testing facility, JT-60, which started operations in April, 1985 at JAPAN ATOMIC ENERGY RESEARCH INSTITUTE. This paper describes an outline of the flywheel motor-generator and discusses the determination of the Xd' value which affects the voltage regulation characteristic of the motor-generator and the twenty-four pulse rectifier circuit, the compensation effect of AVR for the voltage regulation characteristic, the temperature rise and stress of the flywheel which is the largest one in the world and the torsional vibration caused by a thyristor starter, together with the results of field tests. 相似文献
47.
Mitsuru Kudo Akira Takeuchi Yousuke Nozaki Hisahito Endo Jiro Sumita 《Electrical Engineering in Japan》2009,167(4):16-23
Recently, there has been an increase in concern about the global environment. Interest is growing in developing an energy network by which new energy systems such as photovoltaic and fuel cells generate power locally and electrical power and heat are controlled with a communication network. We developed the power generation forecast method for photovoltaic power systems in an energy network. The method makes use of weather information and regression analysis. We carried out forecasting power output of the photovoltaic power system installed in Expo 2005, Aichi Japan. As a result of comparing measurements with prediction values, the average prediction error per day was about 26% of the measured power. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(4): 16–23, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20755 相似文献
48.
Hydrothermal electrolysis of organic compound in the presence of electrolyte was conducted for a woody biomass model compound. The reaction behavior of 1-butanol as a woody biomass model compound was studied in subcritical conditions at 200-250 °C and 8-12 MPa with a batch autoclave. The autoclave volume was 500 mL and equipped system with agitation stirrer, electric current control, electric heating and temperature control and a pressure gauge. The chemical species in aqueous products were identified by gas chromatography mass spectrometry (GC-MS) and quantified using gas chromatography flame ionization detector (GC-FID). The gaseous products were analyzed by gas chromatography with a thermal conductivity detector (GC-TCD). The effects of reaction temperature, pressure and applied constant current on the conversion process of 1-butanol were presented. The main products from the conversion of 1-butanol were butanal, butyric acid, hydrogen and carbon dioxide. Additionally, the values of reaction rate constant for butanal and butyric acid formation were calculated at 200 and 250 °C by kinetic study. 相似文献
49.
Changes in the amounts of water-soluble umami-related substances in porcine longissimus and biceps femoris muscles during moist heat cooking 总被引:1,自引:0,他引:1
Time course changes in amounts of glutamic acid, total free amino acid, inosine monophosphate (IMP), and 2%-trichloroacetic acid-soluble oligopeptides in whole, muscle only, and cooking juice during wet-heat cooking in pork longissimus and biceps femoris muscles were investigated because the movements of umami-relevant substances during cooking treatment had not previously been clarified in detail. The amounts of glutamic acid, total free amino acid, and IMP significantly (P<.05) decreased and increased in muscle and cooking juice during 180min of cooking, respectively. The whole amounts of glutamic acid and total free amino acid remained unchanged during cooking treatment. The whole amount of IMP, however, increased significantly at 10min of cooking (P<.05) and was maintained after the 10-min period. The extramuscular oligopeptides amount increased significantly in response to the cooking treatment (P<.05). The intramuscular amount of oligopeptides decreased at 30min of cooking but increased significantly (P<.05) after 60min. The whole meat oligopeptides amount increased significantly during a 180-min cooking treatment (P<.05). These results indicate that glutamate, total free amino acid, and IMP were released from the muscle during cooking, and that IMP levels increased in the initial phase of cooking. In addition, oligopeptides increased during wet-heat cooking of pork muscles. 相似文献
50.
Okumura Y. Shirahata M. Hachisuka A. Okudaira T. Arima H. Matsukawa T. 《Electron Devices, IEEE Transactions on》1992,39(11):2541-2552
The source-to-drain nonuniformly doped channel (NUDC) MOSFET has been investigated to improve the aggravation of the V th lowering characteristics and to prevent the degradation of the current drivability. The basic concept is to change the impurity ions to control the threshold voltage, which are doped uniformly along the channel in the conventional channel MOSFET, to a nonuniform profile of concentration. The MOSFET was fabricated by using the oblique rotating ion implantation technique. As a result, the V th lowering at 0.4-μm gate length of the NUDC MOSFET is drastically suppressed both in the linear region and in the saturation region as compared with that of the conventional channel MOSFET. Also, the maximum carrier mobility at 0.4-μm gate length is improved by about 20.0%. Furthermore, the drain current is increased by about 20.0% at 0.4-μm gate length 相似文献