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991.
John Q Zhang Lisa L Ji Donovan L Fogt Vicki S Fretwell 《Journal of applied physiology》2007,103(4):1339-1345
We examined the effect of exercise on postprandial hypertriglyceridemia (PHTG) and insulin resistance in individuals with metabolic syndrome. Subjects were 10 hypertriglyceridemic men with insulin resistance [age = 35.0 +/- 1.8 yr, body weight = 90.7 +/- 3.3 kg, fasting triglyceride (TG) = 2.6 +/- 0.4 mmol/l, peak oxygen consumption ((.)Vo(2peak)) = 36.0 +/- 1.3 ml(-1).kg(-1).min(-1), and homeostatic model assessment of insulin resistance (HOMA-IR)= 3.1 +/- 0.3]. Each participant performed a control trial (Ctr; no exercise) and three exercise trials at 60% of their (.)Vo(2peak) for 30 min (30 min-Ex), 45 min (45 min-Ex) and 60 min (60 min-Ex). All subjects had a fat meal in each trial. In the exercise trials, the subject jogged on a treadmill for a designated duration of 12 h before ingestion of a fat meal. Blood samples were taken at 0 h (before the meal) and at 2, 4, 6, and 8 h after the meal. The plasma TG, area score under TG concentration curve over an 8-h period (TG AUC) after the meal, and HOMA-IR were analyzed. The TG AUC scores in both the 45 min-Ex and 60 min-Ex were 31 and 33% lower, respectively, than Ctr (P < 0.02). There were no significant differences in TG AUC scores between the 30 min-Ex and the Ctr (P > 0.05). There were no trial differences in the fasting plasma glucose concentration (P > 0.05). HOMA-IR values in the 30 min-Ex, 45 min-Ex, and 60 min-Ex trials were lower than the Ctr (P < 0.03), but no significant differences were found in HOMA-IR among the exercise trials. The results suggest that for physically inactive individuals with metabolic syndrome, exercising at moderate intensity for 45 min effectively attenuates PHTG while exercise for 30 min is sufficient to improve insulin action. 相似文献
992.
Jun Zhang Jian Chen Yi-Fei Wu Zi-Ping Wang Ji-Guo Qiu Xiao-Long Li Feng Cai Ke-Qing Xiao Xiao-Xu Sun Barry P. Rosen Fang-Jie Zhao 《Environmental microbiology》2022,24(2):752-761
Arsenic can be biomethylated to form a variety of organic arsenicals differing in toxicity and environmental mobility. Trivalent methylarsenite (MAs(III)) produced in the methylation process is more toxic than inorganic arsenite (As(III)). MAs(III) also serves as a primitive antibiotic and, consequently, some environmental microorganisms have evolved mechanisms to detoxify MAs(III). However, the mechanisms of MAs(III) detoxification are not well understood. In this study, we identified an arsenic resistance (ars) operon consisting of three genes, arsRVK, that contribute to MAs(III) resistance in Ensifer adhaerens ST2. ArsV is annotated as an NADPH-dependent flavin monooxygenase with unknown function. Expression of arsV in the arsenic hypersensitive Escherichia coli strain AW3110Δars conferred resistance to MAs(III) and the ability to oxidize MAs(III) to MAs(V). In the presence of NADPH and either FAD or FMN, purified ArsV protein was able to oxidize both MAs(III) to MAs(V) and Sb(III) to Sb(V). Genes with arsV-like sequences are widely present in soils and environmental bacteria. Metagenomic analysis of five paddy soils showed the abundance of arsV-like sequences of 0.12–0.25 ppm. These results demonstrate that ArsV is a novel enzyme for the detoxification of MAs(III) and Sb(III) and the genes encoding ArsV are widely present in soil bacteria. 相似文献
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Plasmonics - The strong light scattering from SPR has received an extraordinary attention due to the useful applications in photodetectors and cell and biomedical imaging. However, the applications... 相似文献
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Brazier Thomas Cherif Emira Martin Jean-François Gilles André Blanchet Simon Zhao Yahui Combe Marine McCairns R. J. Scott Gozlan Rodolphe E. 《Biological invasions》2022,24(8):2399-2420
Biological Invasions - Insufficient data on the origins of the first introduced propagule and the initial stages of invasion complicate the reconstruction of a species’ invasion history.... 相似文献
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Shen Li Zhu Jianqing Lin Yuxiang Fang Jie Wang Yongqiang Tang Liying Zhao Qinghao Xiao Mengqi Duan Feiyu Liu Qunxiu Yu Weidong Jiang Weibin 《Organisms Diversity & Evolution》2022,22(3):659-667
Organisms Diversity & Evolution - The butterfly tribe Tagiadini Mabille, 1878 is a large group of skippers. Although there are a few species which are limited in distribution to some countries... 相似文献