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31.
Zi Feng Yang Chris Ka Pun Mok Xiao Qing Liu Xiao Bo Li Jian Feng He Wen Da Guan Yong Hao Xu Wei Qi Pan Li Yan Chen Yong Ping Lin Shi Guan Wu Si Hua Pan Ji Cheng Huang Guo Yun Ding Kui Zheng Chang Wen Ke Jin Yan Lin Yong Hui Zhang Horace Hok Yeung Lee Wen Kuan Liu Chun Guang Yang Rong Zhou Joseph Sriyal Malik Peiris Yi Min Li Rong Chang Chen Ling Chen Nan Shan Zhong 《PloS one》2015,10(2)
BackgroundThe second wave of avian influenza H7N9 virus outbreak in humans spread to the Guangdong province of China by August of 2013 and this virus is now endemic in poultry in this region.MethodsFive patients with H7N9 virus infection admitted to our hospital during August 2013 to February 2014 were intensively investigated. Viral load in the respiratory tract was determined by quantitative polymerase chain reaction (Q-PCR) and cytokine levels were measured by bead-based flow cytometery.ResultsFour patients survived and one died. Viral load in different clinical specimens was correlated with cytokine levels in plasma and broncho-alveolar fluid (BALF), therapeutic modalities used and clinical outcome. Intravenous zanamivir appeared to be better than peramivir as salvage therapy in patients who failed to respond to oseltamivir. Higher and more prolonged viral load was found in the sputum or endotracheal aspirates compared to throat swabs. Upregulation of proinflammatory cytokines IP-10, MCP-1, MIG, MIP-1α/β, IL-1β and IL-8 was found in the plasma and BALF samples. The levels of cytokines in the plasma and viral load were correlated with disease severity. Reactivation of herpes simplex virus type 1(HSV-1) was found in three out of five patients (60%).ConclusionExpectorated sputum or endotracheal aspirate specimens are preferable to throat swabs for detecting and monitoring H7N9 virus. Severity of the disease was correlated to the viral load in the respiratory tract as well as the extents of cytokinemia. Reactivation of HSV-1 may contribute to clinical outcome. 相似文献
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33.
Shu‐Hong Chen Xiao‐Nan Liu Yan Peng 《Journal of cellular and molecular medicine》2019,23(9):5895-5906
Gestational diabetes mellitus (GDM) is known as different degree glucose intolerance that is initially identified during pregnancy. MicroRNAs (miRs) may be a potential candidate for treatment of GDM. Herein, we suggested that miR‐351 could be an inhibitor in the progression of GDM via the phosphoinositide 3‐kinase/protein kinase B (PI3K/AKT) pathway. Microarray analysis was used to identify differentially expressed genes and predict miRs regulating flotillin 2 (FLOT2). Target relationship between miR‐351 and FLOT2 was verified. Gestational diabetes mellitus mice were treated with a series of mimic, inhibitor and small interfering RNA to explore the effect of miR‐351 on insulin resistance (IR), cell apoptosis in pancreatic tissues and liver gluconeogenesis through evaluating GDM‐related biochemical indexes, as well as expression of miR‐351, FLOT2, PI3K/AKT pathway‐, IR‐ and liver gluconeogenesis‐related genes. MiR‐351 and FLOT2 were reported to be involved in GDM. FLOT2 was the target gene of miR‐351. Gestational diabetes mellitus mice exhibited IR and liver gluconeogenesis, up‐regulated FLOT2, activated PI3K/AKT pathway and down‐regulated miR‐351 in liver tissues. Additionally, miR‐351 overexpression and FLOT2 silencing decreased the levels of FLOT2, phosphoenolpyruvate carboxykinase, glucose‐6‐phosphatase, fasting blood glucose, fasting insulin, total cholesterol, triglyceride, glyeosylated haemoglobin and homeostasis model of assessment for IR index (HOMA‐IR), extent of PI3K and AKT phosphorylation, yet increased the levels of HOMA for islet β‐cell function, HOMA for insulin sensitivity index and glucose transporter 2 expression, indicating reduced cell apoptosis in pancreatic tissues and alleviated IR and liver gluconeogenesis. Our results reveal that up‐regulation of miR‐351 protects against IR and liver gluconeogenesis by repressing the PI3K/AKT pathway through regulating FLOT2 in GDM mice, which identifies miR‐351 as a potential therapeutic target for the clinical management of GDM. 相似文献
34.
Rab39, a novel Golgi-associated Rab GTPase from human dendritic cells involved in cellular endocytosis 总被引:5,自引:0,他引:5
Chen T Han Y Yang M Zhang W Li N Wan T Guo J Cao X 《Biochemical and biophysical research communications》2003,303(4):1114-1120
Rab GTPases are Ras-like small molecular weight GTP binding proteins that are involved in various steps along the exocytic and endocytic pathways. Here we report that Rab39, a novel Rab protein, is a Golgi-associated protein involved in endocytosis of HeLa cells. Full-length cDNA of Rab39 contains 1251bp with an open reading frame (ORF) of 636bp, which is predicted to encode a 211 aa protein. By blast analysis of Rab39 cDNA and protein sequence with homologues, we find that Rab39 may be a short variant of Rab34. Rab39 contains conserved motifs involved in phosphate/guanosine binding and a microbody C-terminal targeting signal. RT-PCR analysis indicates that Rab39 is mainly detected in epithelial cell lines, and Northern blot analysis shows that Rab39 is expressed ubiquitously in human tissues. By using FITC-BSA as an endocytic tracer, we show that Rab39 can facilitate endocytosis in HeLa cells when expressed either transiently or stably. Confocal microscopy examination of Rab39 subcellular localization suggests that Rab39 is associated with Golgi-associated organelles. Our findings demonstrate that Rab39 is a novel Rab GTPase involved in cellular endocytosis. 相似文献
35.
等电聚焦表明,北京鸭红细胞铜锌超氧化物歧化酶由等电点分别为5.0,5.3,5.9,6.1和6.5的五个主要的活性组分(电荷异构体)构成,利用分析型聚丙烯酰胺凝胶等电聚焦电泳进行电荷异构体的制备级分离,采用三氯乙酸沉淀法快速确定蛋白条带的位置,电渗洗脱法回收蛋白,获得其中两个电荷异构体,对比研究结果表明电荷异构体的活性,氨基酸组成,二级结构等性质无明显差异。 相似文献
36.
Liqun Chen Guangbo Qu Xue Sun Shuping Zhang Lei Wang Nan Sang Yuguo Du Jun Liu Sijin Liu 《PloS one》2013,8(3)
Mixture toxicity is an important issue for the risk assessment of environmental pollutants, for which an extensive amount of data are necessary in evaluating their potential adverse health effects. However, it is very hard to decipher the interaction between compounds due to limited techniques. Contamination of heavy metals and organophosphoric insecticides under the environmental and biological settings poses substantial health risk to humans. Although previous studies demonstrated the co-occurrence of cadmium (Cd) and chlorpyrifos (CPF) in environmental medium and food chains, their interaction and potentially synergistic toxicity remain elusive thus far. Here we integrated the approaches of thin-layer chromatography and 1H NMR to study the interaction between Cd2+ and CPF in inducing hepatoxicity. A novel interaction was identified between Cd2+ and CPF, which might be the bonding between Cd2+ and nitrogen atom in the pyridine ring of CPF, or the chelation formation between one Cd2+ and two CPF molecules. The Cd-CPF complex was conferred with distinct biological fate and toxicological performances from its parental components. We further demonstrated that the joint hepatoxicity of Cd ion and CPF was chiefly due to the Cd-CPF complex-facilitated intracellular transport associated with oxidative stress. 相似文献
37.
个体辨别对于减少同种争斗以及配偶选择具有重要意义。我们用棉棒粘取鳄蜥(Shinisaurus crocodilurus)尿液作为气味源,以香水作为对照,测定鳄蜥对熟悉个体气味、陌生个体气味以及香水的舔舌次数和舔舌潜伏期,来探讨鳄蜥通过化学信息辨别熟悉和陌生个体的能力。结果显示,不论是雌性还是雄性,对不同个体尿液的舔舌次数均显著高于对香水的,舔舌潜伏期显著短于香水的;尽管雄性对陌生同性个体气味与熟悉同性个体气味的舔舌次数无显著差异,但对前者的舔舌潜伏期显著短于后者;雄性对陌生雌性气味的舔舌次数显著多于熟悉雌性气味的,对前者的舔舌潜伏期显著短于后者;雌性对陌生雄性气味的舔舌潜伏期显著短于对熟悉雄性气味的;雄鳄蜥对陌生雌性气味的舔舌次数显著多于雌鳄蜥对陌生雄性的。结果表明,鳄蜥能辨别同种个体的化学信息,并能通过化学信息来辨别熟悉和陌生个体,推测鳄蜥的这种辨别能力对其领域分配以及繁殖交配有重要作用。 相似文献
38.
象山港日本对虾增殖放流的效果评价 总被引:5,自引:0,他引:5
日本对虾是中国近海重要的增殖品种,2010年象山港分两批次放流日本对虾苗种约1.67亿尾。通过对放流苗种存活状况、洄游分布、生长特性及回捕情况的跟踪调查,对象山港日本对虾的增殖效果做出初步评价。结果表明:(1)日本对虾放流苗种在8月中旬成为补充群体,集中于港区底部进行索饵育肥;9月中旬,第1、2批放流苗种的平均体长分别达到95.4 mm和71.4 mm,成活率分别约为0.79%和1.06%;10月上旬,随着港区水温降低,增殖苗种资源量锐减。(2)协方差分析表明:日本对虾增殖群体和自然群体的体长-体重关系存在显著性差异,增殖群体的体征状况明显优于自然群体。(3)日本对虾放流苗种在港区主要为桁杆拖虾和地笼网渔业所利用,在港区滞留期间,回捕率约为0.25%。总结发现:栖息地破坏及放流苗种的过早利用是制约象山港日本对虾增殖效果的重要因素,优化增殖策略、保护港区生态环境应是今后港区增殖工作的重点。 相似文献
39.
Zhou G Li H DeCamp D Chen S Shu H Gong Y Flaig M Gillespie JW Hu N Taylor PR Emmert-Buck MR Liotta LA Petricoin EF Zhao Y 《Molecular & cellular proteomics : MCP》2002,1(2):117-124
The reproducibility of conventional two-dimensional (2D) gel electrophoresis can be improved using differential in-gel electrophoresis (DIGE), a new emerging technology for proteomic analysis. In DIGE, two pools of proteins are labeled with 1-(5-carboxypentyl)-1'-propylindocarbocyanine halide (Cy3) N-hydroxy-succinimidyl ester and 1-(5-carboxypentyl)-1'-methylindodi-carbocyanine halide (Cy5) N-hydroxysuccinimidyl ester fluorescent dyes, respectively. The labeled proteins are mixed and separated in the same 2D gel. 2D DIGE was applied to quantify the differences in protein expression between laser capture microdissection-procured esophageal carcinoma cells and normal epithelial cells and to define cancer-specific and normal-specific protein markers. Analysis of the 2D images from protein lysates of approximately 250,000 cancer cells and normal cells identified 1038 protein spots in cancer cell lysates and 1088 protein spots in normal cell lysates. Of the detected proteins, 58 spots were up-regulated by >3-fold and 107 were down-regulated by >3-fold in cancer cells. In addition to previously identified down-regulated protein annexin I, tumor rejection antigen (gp96) was found up-regulated in esophageal squamous cell cancer. Global quantification of protein expression between laser capture-microdissected patient-matched cancer cells and normal cells using 2D DIGE in combination with mass spectrometry is a powerful tool for the molecular characterization of cancer progression and identification of cancer-specific protein markers. 相似文献
40.
本文报告尖吻蝮咬伤并心脏受累20例。经中西医结合治愈19例(95%),死亡1例(5%),并对其发病机理及治疗进行了讨论。 相似文献