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101.
Idiopathic dilated cardiomyopathy (IDC) has been hypothesized as a multifactorial disorder initiated by an environment trigger
in individuals with predisposing human leukocyte antigen (HLA) alleles. Published data on the association between HLA-DR polymorphism
and IDC risk are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. A total
of 19 case–control studies including 1,378 cases and 10,383 controls provided data on the association between HLA-DR polymorphism
and genetic susceptibility to IDC. Overall, statistically elevated frequencies of HLA-DR4 (OR 1.58; 95% CI 1.21–2.07; P = 0.0009) and HLA-DR5 (OR 1.35; 95% CI 1.05–1.73; P = 0.02) alleles were found in patients with IDC compared with controls. Individuals with HLA-DR3 antigen have a protective
effect against IDC (OR 0.72; 95% CI 0.58–0.90; P = 0.004). In summary, this meta-analysis indicated that certain HLA-DR alleles may be genetic markers for susceptibility
and resistance to IDC. 相似文献
102.
Molecular and biochemical characterization of a novel xylanase from the symbiotic <Emphasis Type="Italic">Sphingobacterium</Emphasis> sp. TN19 总被引:1,自引:0,他引:1
103.
Monitoring vegetation recovery after China’s May 2008 Wenchuan earthquake using Landsat TM time-series data: a case study in Mao County 总被引:2,自引:0,他引:2
Tao Lu Hongcheng Zeng Yan Luo Qian Wang Fusun Shi Geng Sun Yan Wu Ning Wu 《Ecological Research》2012,27(5):955-966
The Wenchuan earthquake (Richter scale 8) on 12 May 2008 in southwestern China caused widespread ecosystem damage in the Longmenshan area. It is important to evaluate natural vegetation recovery processes and provide basic information on ecological aspects of the recovering environment after the earthquake. To circumvent the weather limits of remote sensing in the Wenchuan earthquake-hit areas, and to meet the need for regional observation analyses, three Landsat TM images pre- and post-earthquake in Mao County were used for analysis. Post-earthquake normalized difference vegetation index (NDVI) values were compared to pre-earthquake values with an NDVI-based index differencing method to determine the extent to which the vegetation was damaged in relation to the pre-earthquake pattern, and the rate of recovery was evaluated. The spatial characteristics of vegetation loss and natural recovery patterns were analyzed in relation to elevation, slope and aspect. The results indicated that severely damaged sites occurred mainly in river valleys, within a range of 1,500?C2,500?m elevation and on slopes of 25?C55°. The distance from rivers, rather than the distance from active faults, controls the damage patterns. After 1?year of natural regeneration, 36?% of the destroyed areas showed a decrease in NDVI value, 28.8?% showed very little change, 19.1?% showed an increase, and 16.1?% also increased with a recovery rate greater than 100?%. Moreover, there is a good correlation between recovery rate and both slope and elevation, but recovery patterns in the damaged area are complicated. Our results indicate that natural recovery in this arid valley is a slow process. 相似文献
104.
旨在探讨人参总皂苷对K562细胞STAT5表达的影响.MTT法显示TSPG对K562细胞增殖抑制程度呈剂量与时间依赖性增加,且呈正相关关系.流式细胞术表明TSPG能阻止K562细胞从G0/G1期向S、G2/M期移行.激光共聚焦显微镜观察可见,TSPG 200 mg/L作用K562细胞24 h,胞浆中的STAT5荧光强度增加,而胞核内STAT5荧光强度减弱.Western blotting结果显示,TSPG作用K562细胞6 、24 、48 h,胞核中STAT5表达较对照组减少,TSPG作用72 h胞核蛋白中STAT5表达增加;TSPG作用K562细胞6 、12、24、48、72 h,胞浆内STAT5表达增加.TSPG能减少K562胞核中STAT5的表达,这可能是TSPG抑制K562细胞增殖的作用机制之一. 相似文献
105.
Yixin Xie Min Wang Jingjing Tian Xianping Li Min Yang Kan Zhang Shan Tan Lingli Luo Can Luo Longkai Peng Aiguo Tang 《Journal of cellular and molecular medicine》2019,23(10):6530-6542
Advances in microarray, RNA‐seq and omics techniques, thousands of long non‐coding RNAs (lncRNAs) with unknown functions have been discovered. LncRNAs have presented a diverse perspective on gene regulation in diverse biological processes, especially in human immune response. Macrophages participate in the whole phase of immune inflammatory response. They are able to shape their phenotype and arouse extensive functional activation after receiving physiological and pathological stimuli. Emerging studies indicated that lncRNAs participated in the gene regulatory network during complex biological processes of macrophage, including macrophage‐induced inflammatory responses. Here, we reviewed the existing knowledges of lncRNAs in the processes of macrophage development and polarization, and their roles in several different inflammatory diseases. Specifically, we focused on how lncRNAs function in macrophage, which might help to discover some potential therapeutic targets and diagnostic biomarkers. 相似文献
106.
Ruihan Zhang Xin Li Zhongjie Liang Kongkai Zhu Junyan Lu Xiangqian Kong Sisheng Ouyang Lin Li Yujun George Zheng Cheng Luo 《PloS one》2013,8(8)
Protein arginine methyltransferase 1 (PRMT1), the major arginine asymmetric dimethylation enzyme in mammals, is emerging as a potential drug target for cancer and cardiovascular disease. Understanding the catalytic mechanism of PRMT1 will facilitate inhibitor design. However, detailed mechanisms of the methyl transfer process and substrate deprotonation of PRMT1 remain unclear. In this study, we present a theoretical study on PRMT1 catalyzed arginine dimethylation by employing molecular dynamics (MD) simulation and quantum mechanics/molecular mechanics (QM/MM) calculation. Ternary complex models, composed of PRMT1, peptide substrate, and S-adenosyl-methionine (AdoMet) as cofactor, were constructed and verified by 30-ns MD simulation. The snapshots selected from the MD trajectory were applied for the QM/MM calculation. The typical SN2-favored transition states of the first and second methyl transfers were identified from the potential energy profile. Deprotonation of substrate arginine occurs immediately after methyl transfer, and the carboxylate group of E144 acts as proton acceptor. Furthermore, natural bond orbital analysis and electrostatic potential calculation showed that E144 facilitates the charge redistribution during the reaction and reduces the energy barrier. In this study, we propose the detailed mechanism of PRMT1-catalyzed asymmetric dimethylation, which increases insight on the small-molecule effectors design, and enables further investigations into the physiological function of this family. 相似文献
107.
Combined effect of sodium dodecyl sulfate and enzyme on waste activated sludge hydrolysis and acidification 总被引:4,自引:0,他引:4
Luo K Yang Q Yu J Li XM Yang GJ Xie BX Yang F Zheng W Zeng GM 《Bioresource technology》2011,102(14):7103-7110
The combined effect of sodium dodecyl sulfate (SDS) and enzyme system on hydrolysis and acidification of waste activated sludge (WAS) was investigated. The results showed that the combined system was more effective in the promotion of sludge hydrolysis than sole SDS and sole enzyme, and the SDS + mixed-enzymes (ME) system had better hydrolysis performance than SDS + single enzyme system. Compared with SDS + protease and SDS + amylase systems, the soluble protein concentration in SDS + ME system increased respectively by 20.0% and 44.4%, and the soluble carbohydrate concentration increased by 78.3% and 37.0%, respectively. During the WAS acidification stage, the SDS, ME and SDS + ME system could make the maximum short-chain fatty acids (SCFAs) concentration increased by 1.82 (6th day), 2.04 (5th day), 2.32 (7th day) times, respectively. The composition analysis of SCFAs produced in SDS + ME system indicated that acetic acid was the most prevalent product and propionic acid was the second one. 相似文献
108.
Su K Tian Y Wang J Shi W Luo D Liu J Tong Z Wu J Zhang J Wei L 《DNA and cell biology》2012,31(6):1078-1087
Metastasis is the leading cause of death in breast cancer patients. Recent evidence suggests that inflammation-related cytokine tumor necrosis factor-alpha (TNF-α) is implicated in tumor invasion and metastasis, but the mechanism of its involvement remains elusive. In this study, we employed MCF-7 breast cancer cells as an experimental model to demonstrate that TNF-α inhibits breast cancer cell adhesion and cell proliferation through hypoxia inducible factor-1alpha (HIF-1α) mediated suppression of vasodilator-stimulated phosphoprotein (VASP). We observed that TNF-α treatment attenuated the adhesion and proliferation of MCF-7 cells it also dramatically increased HIF-1α expression and decreased VASP expression. Through a variety of approaches, including promoter assay, electrophoretic mobility shift assay (EMSA), and chromatin immunoprecipitation (ChIP), we identified VASP as a direct target gene of HIF-1α. In addition, we confirmed that HIF-1α mediated the repression of VASP expression by TNF-α in MCF-7 cells. We also demonstrated that exogenous VASP expression or knockdown of HIF-1α relieved TNF-α induced inhibition of cell adhesion and proliferation. We identified a novel TNF-α/HIF-1α/VASP axis in which HIF-1α acts downstream of TNF-α to inhibit VASP expression and modulate the adhesion and proliferation of breast cancer cells. These data provide new insight into the potential anti-tumor effects of TNF-α. 相似文献
109.
Salvador promotes both cell cycle exit and apoptosis through the modulation of both cyclin E and Drosophila inhibitor of apoptosis protein in Drosophila. However, the cellular function of human Salvador (hSav1) is rarely reported. To screen for novel binding proteins that interact with hSav1, the cDNA of hSav1 was cloned into a bait protein plasmid, and positive clones were screened from a human fetal liver cDNA library by the yeast two-hybrid system. hSav1 mRNA was expressed in yeast and there was no self-activation and toxicity in the yeast strain AH109. Twenty proteins were found to interact with hSav1, including HS1 (haematopoietic cell specific protein1)-associated protein X-1 (HAX-1); neural precursor cell expressed, developmentally down-regulated 9, pyruvate kinase, liver and RBC, cytochrome c oxidase subunit Vb, enoyl coenzyme A hydratase short chain 1, and NADH dehydrogenase (ubiquinone) 1 beta subcomplex, demonstrating that the yeast two-hybrid system is an efficient method for investigating protein interactions. Among the identified proteins, there were many mitochondrial proteins, indicating that hSav1 may play a role in mitochondrial function. We also confirmed the interaction of HAX-1 and hSav1 in mammalian cells. This investigation provides functional clues for further exploration of potential apoptosis-related proteins in disease biotherapy. 相似文献
110.
为了检测水稻种子的耐盐相关数量性状位点,也为耐盐遗传机理的研究提供理论基础,本实验以Koshihikari(受体)和Nona Bokra(供体)为亲本构建的全基因组单片段代换系(154个)作为研究群体,采用培养皿培养,在水稻种子的萌发期进行浓度为1%的盐胁迫,以种子的发芽情况为指标,统计发芽率数据,利用分子标记技术,定... 相似文献