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81.
Rongrong Bi Yancheng Dai Zifeng Ma Shaoyan Zhang Lei Wang Qichang Lin 《Journal of cellular biochemistry》2019,120(3):4214-4224
Chronic intermittent hypoxia (CIH) in obstructive sleep apnea causes damage of aortic endothelial cells, which predisposes the development of many cardiovascular diseases. Recently, both altered expression of microRNAs (miRNAs) and impaired autophagy were found to be associated with endothelial cell dysfunction in CIH. However, the exact molecular regulatory pathway has not been determined. Here, we address this question. In a mouse model of CIH, we detected significant upregulation of miR-30a, a miRNA that targets 3′-untranslated region of autophagy-associated protein 6 (Beclin-1) messenger RNA (mRNA) for suppressing the protein translation, which subsequently attenuated the endothelial cell autophagy against cell death. Indeed, unlike Beclin-1 mRNA, the Beclin-1 protein in endothelial cells did not increase after CIH. Suppression of miR-30a by expression of antisense of miR-30a significantly increased Beclin-1 levels to enhance endothelial cell autophagy in vitro and in vivo, which improved endothelial cell survival against CIH. Together, these data suggest that endothelial cell autophagy in CIH may be attenuated by miR-30a-mediated translational control of Beclin-1 as an important cause of endothelial cell dysfunction and damage. 相似文献
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84.
天敌对麦长管蚜和麦二叉蚜种群数量影响程度的分析 总被引:6,自引:0,他引:6
通过对1993~1996年两种麦蚜种群数量及其天敌数量的系统调查,并采用灰色关联分析法,研究各种天敌对两种麦蚜种群数量的影响程度,得出对麦长管蚜种群数量影响最大的是龟纹瓢虫、蚜茧蜂和食蚜蝇;对麦二叉蚜种群数量影响最大的是草间小黑蛛,其次是龟纹瓢虫. 相似文献
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86.
小麦高分子量谷蛋白亚基对加工品质影响的效应分析 总被引:28,自引:2,他引:28
分析了 2 50份小麦材料的高分子量谷蛋白亚基 (HMW- GS)组成以及其中 66份材料的加工品质及面条制作品质。回归分析表明 :HMW- GS与 1 0种加工品质性状均有显著的线性关系。不同亚基对综合品质效应的得分大小依次为 :Glu- Al,1 >2 * >null;Glu- Bl,1 4 +1 5>7+8>1 7+1 8>>7+9;Glu- Dl,5+1 0 >>2 +1 2 >4+1 2。不同基因位点对品质的贡献大小顺序为 :Glu- Dl>Glu- Al>Glu- Bl。首次提出了 HMW- GS综合品质评分系统 相似文献
87.
Bi Song Alexandra M. Smink Christina V. Jones Judy M. Callaghan Stephen D. Firth Claude A. Bernard Andrew L. Laslett Peter G. Kerr Sharon D. Ricardo 《PloS one》2012,7(9)
The loss of glomerular podocytes is a key event in the progression of chronic kidney disease resulting in proteinuria and declining function. Podocytes are slow cycling cells that are considered terminally differentiated. Here we provide the first report of the directed differentiation of induced pluripotent stem (iPS) cells to generate kidney cells with podocyte features. The iPS-derived podocytes share a morphological phenotype analogous with cultured human podocytes. Following 10 days of directed differentiation, iPS podocytes had an up-regulated expression of mRNA and protein localization for podocyte markers including synaptopodin, nephrin and Wilm’s tumour protein (WT1), combined with a down-regulation of the stem cell marker OCT3/4. In contrast to human podocytes that become quiescent in culture, iPS-derived cells maintain a proliferative capacity suggestive of a more immature phenotype. The transduction of iPS podocytes with fluorescent labeled-talin that were immunostained with podocin showed a cytoplasmic contractile response to angiotensin II (AII). A permeability assay provided functional evidence of albumin uptake in the cytoplasm of iPS podocytes comparable to human podocytes. Moreover, labeled iPS-derived podocytes were found to integrate into reaggregated metanephric kidney explants where they incorporated into developing glomeruli and co-expressed WT1. This study establishes the differentiation of iPS cells to kidney podocytes that will be useful for screening new treatments, understanding podocyte pathogenesis, and offering possibilities for regenerative medicine. 相似文献
88.
Jingdan Xie Qian Bi Wen li Wen Shang Ming Yan Yebing Yang Danmin Miao Huiming Zhang 《PloS one》2012,7(10)
Background
The relationship between anxiety and depression in pain patients has not been clarified comprehensively. Previous research has identified a common factor in anxiety and depression, which may explain why depression and anxiety are strongly correlated. However, the specific clinical features of anxiety and depression seem to pull in opposite directions.Objective
The purpose of this study is to develop a statistical model of depression and anxiety, based on data from pain patients using Hospital Anxiety and Depression Scale (HADS). This model should account for the positive correlation between depression and anxiety in terms of a general factor and also demonstrate a latent negative correlation between the specific factors underlying depression and anxiety.Methods
The anxiety and depression symptoms of pain patients were evaluated using the HADS and the severity of their pain was assessed with the visual analogue scale (VAS). We developed a hierarchical model of the data using an IRT method called bifactor analysis. In addition, we tested this hierarchical model with model fit comparisons with unidimensional, bidimensional, and tridimensional models. The correlations among anxiety, depression, and pain severity were compared, based on both the bidimensional model and our hierarchical model.Results
The bidimensional model analysis found that there was a large positive correlation between anxiety and depression (r = 0.638), and both scores were significantly positively correlated with pain severity. After extracting general factor of distress using bifactor analysis, the specific factors underlying anxiety and depression were weakly but significantly negatively correlated (r = −0.245) and only the general factor was significantly correlated with pain severity. Compared with the three first-order models, the bifactor hierarchical model had the best model fit.Conclusion
Our results support the hypothesis that apart from distress, anxiety and depression are inversely correlated. This finding has not been convincingly demonstrated in previous research. 相似文献89.
Yimin Dai Qingfeng Zhou Chengwen Zhang Yanhua Song Xiaoyan Tian Xiangbin Zhang Chunyi Xue Shun Xu Yingzuo Bi Yongchang Cao 《Journal of virology》2012,86(22):12456
Porcine orthoreoviruses belong to the family Reoviridae and cause mainly mild enteritis in piglets. We present here the complete genome sequence of a novel porcine orthoreovirus strain (GD-1) isolated from a piglet in southern China. Our data will facilitate future investigations of the molecular characteristics and epidemiology of porcine orthoreoviruses. 相似文献
90.
Heterokaryon myotubes with normal mouse and Duchenne nuclei exhibit sarcolemmal dystrophin staining and efficient intracellular free calcium control. 总被引:1,自引:1,他引:1 下载免费PDF全文
Duchenne and mdx muscle tissues lack dystrophin where it normally interacts with glycoproteins in the sarcolemma. Intracellular free calcium ([Ca2+]i) is elevated in Duchenne and mdx myotubes and is correlated with abnormally active calcium-specific leak channels in dystrophic myotubes. We fused Duchenne human and normal mouse myoblasts and identified heterokaryon myotubes by Hoechst 33342 staining to measure the degree to which dystrophin introduced by normal nuclei could incorporate throughout the myotube at the sarcolemma and restore normal calcium homeostasis. Dystrophin expression in myotubes was determined by immunofluorescence and confocal laser scanning microscopy. Dystrophin was expressed at the sarcolemma in normal mouse and heterokaryon myotubes, but not in Duchenne myotubes. In heterokaryons, extensive dystrophin localization occurred at the sarcolemma even where only Duchenne nuclei were present, indicating that dystrophin does not exhibit nuclear domains. Heterokaryon, normal mouse and Duchenne myotube [Ca2+]i was measured using fura-2 and fluorescence ratio imaging. Heterokaryon and normal mouse myotubes were found to maintain similar levels of [Ca2+]i. In contrast, Duchenne myotubes had significantly higher [Ca2+]i (p < 0.001). Furthermore, the ability of heterokaryons to maintain normal [Ca2+]i did not depend on greater numbers of normal nuclei than Duchenne being present in the myotube. These results support the view that dystrophin expression in heterokaryons allows for efficient control of [Ca2+]i. 相似文献