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991.
992.
Shan Huang Yong Xu Wen-Fang Peng Jie Cheng Hui-Hua Li Li-Sha Shen Li-Li Xia 《Journal of cellular physiology》2019,234(7):10640-10645
Asymmetric dimethylarginine (ADMA) plays a vital role in the regulation of insulin sensitivity and has been shown as a potential marker for various disease, including type 2 diabetes mellitus (DM2). However, the correlation between ADMA and impaired glucose tolerance (IGT) and obesity has not been studied. A total of 195 subjects were involved in our study. The characteristics of the subjects in the study cohort were measured and analyzed. We found that the serum ADMA and C-reactive protein levels were significantly increased in IGT and diabetic patients, whereas the levels of lipoprotein A and adiponectin were decreased, especially in diabetic patients with obesity. The serum ADMA level was positively correlated to a homeostatic model assessment for insulin resistance, and multivariate regression analysis further indicated that ADMA was an independent factor for DM patients with obesity. Our study expands the understanding of the complicated relationship between obesity, insulin resistance, IGT, and ADMA. In addition, we demonstrated that the serum ADMA level could serve as a diagnositic biomarker of the early signs for IGT patients with obesity. 相似文献
993.
Yu-mei Li Jin-guo Sun Li-hua Hu Xian-chun Ma Gang Zhou Xi-zhao Huang 《Journal of cellular physiology》2019,234(12):23289-23301
Administration of propofol at the time of reperfusion has shown to protect the heart from ischemia and reperfusion (I/R) injury. The aim of the present study was to investigate the molecular mechanism underling the cardioprotective effect of propofol against myocardial I/R injury (MIRI) in vivo and in vitro. Rat heart I/R injury was induced by ligation of the left anterior descending (LAD) artery for 30 min followed by 2-hr reperfusion. Propofol pretreatment (0.01 mg/g) was performed 10 min before reperfusion. In vitro MIRI was investigated in cultured cardiomyocytes H9C2 following hypoxia/reoxygenation (H/R) injuries. Propofol pretreatment in vitro was achieved in the medium supplemented with 25 μmol/L propofol before H/R injuries. Propofol pretreatment significantly increased miRNA-451 expression, decreased HMGB1 expression, reduced infarct size, and I/R-induced cardiomyocyte apoptosis in rat hearts undergoing I/R injuries. Knockdown of miRNA-451 48 hr before I/R injury was found to increase HMGB1 expression, infarct size, and I/R-induced cardiomyocyte apoptosis in rat hearts in the presence of propofol pretreatment. These in vivo findings were reproduced in vivo that knockdown of miRNA-451 48 hr before H/R injuries increased HMGB1 expression and H/R-induced apoptosis in cultured H9C2 supplemented with propofol. In addition, luciferase activity assays and gain-of-function studies found that propofol could decrease HMGB1, the target of miRNA-541. Taken together our findings provide a first demonstration that propofol-mediated cardioprotection against MIRI is dependent of microRNA-451/HMGB1. The study provides a novel target to prevent I/R injury during propofol anesthesia. 相似文献
994.
Davide Sala Yuanpeng Janet Huang Casey A. Cole David A. Snyder Gaohua Liu Yojiro Ishida G.V.T. Swapna Kelly P. Brock Chris Sander Krzysztof Fidelis Andriy Kryshtafovych Masayori Inouye Roberto Tejero Homayoun Valafar Antonio Rosato Gaetano T. Montelione 《Proteins》2019,87(12):1315-1332
CASP13 has investigated the impact of sparse NMR data on the accuracy of protein structure prediction. NOESY and 15N-1H residual dipolar coupling data, typical of that obtained for 15N,13C-enriched, perdeuterated proteins up to about 40 kDa, were simulated for 11 CASP13 targets ranging in size from 80 to 326 residues. For several targets, two prediction groups generated models that are more accurate than those produced using baseline methods. Real NMR data collected for a de novo designed protein were also provided to predictors, including one data set in which only backbone resonance assignments were available. Some NMR-assisted prediction groups also did very well with these data. CASP13 also assessed whether incorporation of sparse NMR data improves the accuracy of protein structure prediction relative to nonassisted regular methods. In most cases, incorporation of sparse, noisy NMR data results in models with higher accuracy. The best NMR-assisted models were also compared with the best regular predictions of any CASP13 group for the same target. For six of 13 targets, the most accurate model provided by any NMR-assisted prediction group was more accurate than the most accurate model provided by any regular prediction group; however, for the remaining seven targets, one or more regular prediction method provided a more accurate model than even the best NMR-assisted model. These results suggest a novel approach for protein structure determination, in which advanced prediction methods are first used to generate structural models, and sparse NMR data is then used to validate and/or refine these models. 相似文献
995.
996.
997.
Results of Northern blot and Dot blot analysis indicated that actin genes exhibit organ-specific expression in snake gourd (Luffa cylindrica L. ) and cucumber (Cucumis sativum L. ). Actin genes showed obvious developmental specificity during'the development of snake gourd seedlings, mRNA levels in stems of 30-day old seedlings were 4 ~ 6 times higher than that of roots and cotyledons of 8-day old seedlings and roots and hypocotyls of 15-day old seedlings, and were even 10~12 times higher than that of stems and leaves of flowering plants. Actin genes also showed organ-specific expression in young fruits (15 days after flowering) of cucumber. 相似文献
998.
Increased acidic phospholipids in rat brain membranes after chronic ethanol administration 总被引:2,自引:0,他引:2
Two types of plasma membranes isolated from rat brain cortex were used to study the membrane-perturbing properties of ethanol. Rats administered ethanol in the form of a liquid diet showed an increase in levels of phosphatidylserines, phosphatidylinositols and phosphatidic acids as compared to controls. The results present evidence that chronic ethanol treatment results in an increase in the acidic phospholipids in brain membranes. This type of membrane modification may have important implications for the function of membrane transport enzymes such as (Na+, K+)-ATPase, which also increases in activity upon chronic ethanol administration. 相似文献
999.
小鼠胚胎干细胞在六种培养体系的培养观察 总被引:12,自引:2,他引:12
目的 观察小鼠胚胎干细胞在六种培养体系中的生长情况。方法 小鼠胚胎干细胞 (ESD3细胞株 )在以下六种培养体系中培养 :1 .原代小鼠胚胎成纤维细胞 (MEF)有血清培养 ,2 .MEF无血清培养 ,3.SNL细胞有血清培养 ,4.LIF(白血病抑制因子 )有血清无饲养层培养 ,5.LIF无血清无饲养层培养 ,6.大鼠肝细胞 (BRL)条件培养基培养。经体外培养 1 0代后 ,观察其克隆形态 ,同时进行碱性磷酸酶检测并将ES细胞接种于裸小鼠皮下 ,观察ESD3的未分化状态和多潜能性。结果 六种培养体系培养的ESD3具有典型的ES细胞克隆形态 :巢状 (集落状 )隆起生长 ,边缘清楚 ,表面平滑 ,结构致密 ;AKP强阳性 ;裸小鼠体内形成了由多种组织构成的畸胎瘤。结论 六种培养体系均能支持ESD3生长 ,并能保持其未分化性和多潜能性 ,为ES细胞的应用研究奠定了良好的基础。 相似文献
1000.