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101.
Antoine Fleureau Mathieu Lacome Martin Buchheit Antoine Couturier Giuseppe Rabita 《Biology of sport / Institute of Sport》2020,37(4):351
The aim of this study was to examine the concurrent validity of the Kinexon local positioning system (LPS) in comparison with the Vicon motion capture system used as the reference. Five recreationally active men performed ten repetitions of linear sprints, medio-lateral side-to-side and handball-specific movements both in the centre and on the side of an indoor field. Validity was assessed for peak speed, peak acceleration and peak deceleration using standardised biases, Pearson coefficient of correlation (r), and standardised typical error of the estimate. With the exception of peak decelerations during specific movements in the centre and peak acceleration and deceleration during linear sprints on the side of the field, the standardised typical error of the estimate (TEE) values were all small to moderate (0.06–0.48), standardised bias ranged between 0.01 and 2.85 and Pearson coefficient values were all > 0.90 for all variables in all conditions. Peak acceleration and deceleration during linear sprints on the side of the field showed the largest TEEs and the greatest differences between the two systems. The ultra-wideband based (UWB) local positioning system had acceptable validity compared with Vicon to assess players’ movements in handball with the exception of high accelerations and decelerations during linear sprints on the side of the field. 相似文献
102.
Xiao Zhang Jinpeng Li Bo Yang Qina Leng Ji Li Xintuan Wang Junyao Lu Opeyemi Joshua Olatunji Jian Tang 《化学与生物多样性》2021,18(5):e2100065
This study investigated the protective effects of two polysaccharides (CPA-1 and CPB-2) from Cordyceps cicadae against high fructose/high fat diet (HF/HFD) induced obesity and metabolic disorders in rats. Rats were either fed with normal diet or HF/HFD and treated with CPA-1 and CPB-2 (100 and 300 mg/kg) for 11 weeks. Administration of CPA-1 and CPB-2 significantly and dose dependently reduced body and liver weight, insulin and glucose tolerance, serum insulin and glucose levels. Furthermore, serum and hepatic lipid profiles, liver function enzymes and proinflammatory cytokines (TNF-α, IL-1β and IL-6) were markedly reduced. Additionally, CPA-1 and CPB-2 treatment alleviated hepatic oxidative stress by reducing lipid peroxidation level (MDA) and upregulating glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) activities as well as ameliorated histological alterations through the reduction of hepatic lipid accumulation. These results suggested that the polysaccharides from C. cicadae showed protective effects against HF/HFD induced metabolic disturbances and may be considered as a dietary supplement for treating obesity. 相似文献
103.
Peter M. Zygmunt Anna Ermund Pouya Movahed David A. Andersson Charlotte Simonsen Bo A. G. J?nsson Anders Blomgren Bryndis Birnir Stuart Bevan Alain Eschalier Christophe Mallet Ana Gomis Edward D. H?gest?tt 《PloS one》2013,8(12)
Phospholipase C-mediated hydrolysis of phosphatidylinositol 4,5-bisphosphate generates diacylglycerol, inositol 1,4,5-trisphosphate and protons, all of which can regulate TRPV1 activity via different mechanisms. Here we explored the possibility that the diacylglycerol metabolites 2-arachidonoylglycerol and 1-arachidonoylglycerol, and not metabolites of these monoacylglycerols, activate TRPV1 and contribute to this signaling cascade. 2-Arachidonoylglycerol and 1-arachidonoylglycerol activated native TRPV1 on vascular sensory nerve fibers and heterologously expressed TRPV1 in whole cells and inside-out membrane patches. The monoacylglycerol lipase inhibitors methylarachidonoyl-fluorophosphonate and JZL184 prevented the metabolism of deuterium-labeled 2-arachidonoylglycerol and deuterium-labeled 1-arachidonoylglycerol in arterial homogenates, and enhanced TRPV1-mediated vasodilator responses to both monoacylglycerols. In mesenteric arteries from TRPV1 knock-out mice, vasodilator responses to 2-arachidonoylglycerol were minor. Bradykinin and adenosine triphosphate, ligands of phospholipase C-coupled membrane receptors, increased the content of 2-arachidonoylglycerol in dorsal root ganglia. In HEK293 cells expressing the phospholipase C-coupled histamine H1 receptor, exposure to histamine stimulated the formation of 2-AG, and this effect was augmented in the presence of JZL184. These effects were prevented by the diacylglycerol lipase inhibitor tetrahydrolipstatin. Histamine induced large whole cell currents in HEK293 cells co-expressing TRPV1 and the histamine H1 receptor, and the TRPV1 antagonist capsazepine abolished these currents. JZL184 increased the histamine-induced currents and tetrahydrolipstatin prevented this effect. The calcineurin inhibitor ciclosporin and the endogenous “entourage” compound palmitoylethanolamide potentiated the vasodilator response to 2-arachidonoylglycerol, disclosing TRPV1 activation of this monoacylglycerol at nanomolar concentrations. Furthermore, intracerebroventricular injection of JZL184 produced TRPV1-dependent antinociception in the mouse formalin test. Our results show that intact 2-arachidonoylglycerol and 1-arachidonoylglycerol are endogenous TRPV1 activators, contributing to phospholipase C-dependent TRPV1 channel activation and TRPV1-mediated antinociceptive signaling in the brain. 相似文献
104.
John A. Nyakatura Vivian R. Allen Jonas Laustr?er Amir Andikfar Marek Danczak Hans-Jürgen Ullrich Werner Hufenbach Thomas Martens Martin S. Fischer 《PloS one》2015,10(9)
Orobates pabsti, a basal diadectid from the lower Permian, is a key fossil for the understanding of early amniote evolution. Quantitative analysis of anatomical information suffers from fragmentation of fossil bones, plastic deformation due to diagenetic processes and fragile preservation within surrounding rock matrix, preventing further biomechanical investigation. Here we describe the steps taken to digitally reconstruct MNG 10181, the holotype specimen of Orobates pabsti, and subsequently use the digital reconstruction to assess body mass, position of the centre of mass in individual segments as well as the whole animal, and study joint mobility in the shoulder and hip joints. The shape of most fossil bone fragments could be recovered from micro-focus computed tomography scans. This also revealed structures that were hitherto hidden within the rock matrix. However, parts of the axial skeleton had to be modelled using relevant isolated bones from the same locality as templates. Based on the digital fossil, mass of MNG 10181 was estimated using a model of body shape that was varied within a plausible range to account for uncertainties of the dimension. In the mean estimate model the specimen had an estimated mass of circa 4 kg. Varying of the mass distribution amongst body segments further revealed that Orobates carried most of its weight on the hind limbs. Mostly unrestricted joint morphology further suggested that MNG 10181 was able to effectively generate propulsion with the pelvic limbs. The digital reconstruction is made available for future biomechanical studies. 相似文献
105.
Rachel M. Haywood Andrew W. D. Claxson Geoffrey E. Hawkes David P. Richardson Declan P. Naughton Gregory Coumbarides Jane Hawkes Edward J. Lynch Martin C. Grootveld 《Free radical research》1995,22(5):441-482
High field (400 and 600 MHz) proton NMR spectroscopy has been employed to investigate the thermally-induced autoxidation of glycerol-bound polyunsaturated fatty acids present in intact culinary frying oils and fats. Heating of these materials at 180°C for periods of 30, 60 and 90 min. generated a variety of peroxidation products, notably aldehydes (alkanals, trans-2-alkenals and alka-2, 4-dienals) and their conjugated hydroperoxydiene precursors. Since such aldehydes appear to be absorbed into the systemic circulation from the gut in vivo, the toxicological significance of their production during standard frying practices is discussed. 相似文献
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110.
Laurent Chatel-Chaix Marie-Anne Germain Alena Motorina éric Bonneil Pierre Thibault Martin Baril Daniel Lamarre 《Journal of virology》2013,87(21):11704-11720
Hepatitis C virus (HCV) orchestrates the different stages of its life cycle in time and space through the sequential participation of HCV proteins and cellular machineries; hence, these represent tractable molecular host targets for HCV elimination by combination therapies. We recently identified multifunctional Y-box-binding protein 1 (YB-1 or YBX1) as an interacting partner of NS3/4A protein and HCV genomic RNA that negatively regulates the equilibrium between viral translation/replication and particle production. To identify novel host factors that regulate the production of infectious particles, we elucidated the YB-1 interactome in human hepatoma cells by a quantitative mass spectrometry approach. We identified 71 YB-1-associated proteins that included previously reported HCV regulators DDX3, heterogeneous nuclear RNP A1, and ILF2. Of the potential YB-1 interactors, 26 proteins significantly modulated HCV replication in a gene-silencing screening. Following extensive interaction and functional validation, we identified three YB-1 partners, C1QBP, LARP-1, and IGF2BP2, that redistribute to the surface of core-containing lipid droplets in HCV JFH-1-expressing cells, similarly to YB-1 and DDX6. Importantly, knockdown of these proteins stimulated the release and/or egress of HCV particles without affecting virus assembly, suggesting a functional YB-1 protein complex that negatively regulates virus production. Furthermore, a JFH-1 strain with the NS3 Q221L mutation, which promotes virus production, was less sensitive to this negative regulation, suggesting that this HCV-specific YB-1 protein complex modulates an NS3-dependent step in virus production. Overall, our data support a model in which HCV hijacks host cell machinery containing numerous RNA-binding proteins to control the equilibrium between viral RNA replication and NS3-dependent late steps in particle production. 相似文献