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71.
用VeroE6细胞从12例水痘及带状疱疹病人水疱液中分离到10株病毒,分离阳性率为83.3%。10株病毒均具有使感染细胞圆缩、融合、脱落等典型的VZV局灶性细胞病变(CPE)特点,CPE随着传代次数增加而加快。用带状疱疹恢复期病人血清作间接免疫荧光染色镜检,可见典型的感染细胞核内荧光块。10株病毒感染细胞制成的抗原片,检测5例带状疱疹病人急性期及恢复期血清,荧光抗体滴度均有4倍以上增高。VZV对Vero细胞敏感;对沙鼠肾,胎兔肾,胎豚鼠肾、肺、脾原代单层细胞不敏感;对乳小白鼠不敏感。毒种在-20℃保存一周内死亡;但在30%脱脂牛奶、20%小牛血清及10%山梨醇Eagle’s液中,液体或真空冷冻干燥-100℃可保存二年以上。 相似文献
72.
Macrophage migration inhibitory factor (MIF) interacts with Bim and inhibits Bim-mediated apoptosis 总被引:1,自引:0,他引:1
The pro-apoptotic Bcl-2 family member Bim acts as a sensor for apoptotic stimuli and initiates apoptosis through the mitochondrial pathway. To identify novel regulators of Bim, we employed the yeast two-hybrid system and isolated the human gene encoding macrophage migration inhibitory factor (MIF), a ubiquitously expressed proinflammatory mediator that has also been implicated in cell proliferation, the cell cycle and carcinogenesis. The interaction between MIF and Bim was confirmed by both in vitro and in vivo protein interaction assays. Intriguingly, protein complexes between MIF and the three major Bim isoforms (BimEL/BimL/BimS) could be detected in HEK293 and K562 cells, especially in cells undergoing apoptosis. Moreover, exogenous expression of MIF partially inhibited Bim-induced apoptosis in HEK293 cells. SiRNA-mediated knockdown of MIF increased apoptosis in K562 cells exposed to the chemical oxidant diamide. Endogenous MIF may regulate the pro-apoptotic activity of Bim and inhibit the release of cytochrome c from mitochondria. 相似文献
73.
In vivo fluorescence imaging uses a sensitive camera to detect fluorescence emission from fluorophores in whole-body living small animals. To overcome the photon attenuation in living tissue, fluorophores with long emission at the near-infrared (NIR) region are generally preferred, including widely used small indocarbocyanine dyes. The list of NIR probes continues to grow with the recent addition of fluorescent organic, inorganic and biological nanoparticles. Recent advances in imaging strategies and reporter techniques for in vivo fluorescence imaging include novel approaches to improve the specificity and affinity of the probes and to modulate and amplify the signal at target sites for enhanced sensitivity. Further emerging developments are aiming to achieve high-resolution, multimodality and lifetime-based in vivo fluorescence imaging. 相似文献
74.
从中国发病鸡中分离的鸡减蛋综合征病毒(EggDropSyndromVirus,EDSV)弱毒株(AA-2),其基因组全长约为33kb。用限制性内切酶HindⅢ水解EDSV全基因组,构建了以pBluescriptⅡ(KS+)为载体的右末端片段的克隆(约4.2kb),对其进行了序列测定和结构分析。该片段全长4183个碱基对(bp),位于基因组右末端87.3m.u.-100m.u.。结果显示,该片段与哺乳动物腺病毒右末端E4区结构不同,与禽Ⅰ型腺病毒代表株CELO右末端片段亦无同源性。本文为深入了解EDSV基因组结构特点,EDSV与其他腺病毒基因结构与功能的进化关系和EDSV载体的构建奠定了分子生物学基础 相似文献
75.
Silin Wu Ye Gu Yuying Huang Tyh-Chai Wong Hailin Ding Tengfei Liu Yu Zhang Xiaobiao Zhang 《Biochemical genetics》2017,55(3):253-267
The microRNAs (miRNAs) are involved in multiple pathological processes among various types of tumors. However, the functions of miRNAs in benign brain tumors are largely unexplored. In order to explore the pathogenesis of the invasiveness in non-functional pituitary adenoma (NFPA), the miRNAs expression profile was analyzed between invasive and non-invasive non-functional pituitary adenoma by miRNAs microarray. Six most significant differentially expressed miRNAs were identified including four upregulated miRNAs hsa-miR-181b-5p, hsa-miR-181d, hsa-miR-191-3p, and hsa-miR-598 and two downregulated miRNAs hsa-miR-3676-5p and hsa-miR-383. The functions and corresponding signaling pathways of differentially expressed miRNAs were investigated by bioinformatics techniques, including Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. The result of GO analysis indicates regulation of voltage-gated potassium channel activity, positive regulation of sodium ion transport, positive regulation of GTPase activity, negative regulation of Notch signaling pathway, etc. KEGG pathway reveals a series of biological processes, including prolactin signaling pathway, endocrine and other factor-regulated calcium reabsorption, fatty acid metabolism, neuroactive ligand-receptor interaction, etc. The miRNAs hsa-miR-181a-5p was verified by quantitative real-time PCR, and the expression level was in accordance with the microarray result. Our result can provide the evidence on featured miRNAs which play a prominent role in pituitary adenoma as effective biomarkers and therapeutic targets in the future. 相似文献
76.
Detection of the synergetic effects between variants, such as single-nucleotide polymorphisms (SNPs), is crucial for understanding the genetic characters of complex diseases. Here, we proposed a two-step approach to detect differentially inherited SNP modules (synergetic SNP units) from a SNP network. First, SNP-SNP interactions are identified based on prior biological knowledge, such as their adjacency on the chromosome or degree of relatedness between the functional relationships of their genes. These interactions form SNP networks. Second, disease-risk SNP modules (or sub-networks) are prioritised by their differentially inherited properties in IBD (Identity by Descent) profiles of affected and unaffected sibpairs. The search process is driven by the disease information and follows the structure of a SNP network. Simulation studies have indicated that this approach achieves high accuracy and a low false-positive rate in the identification of known disease-susceptible SNPs. Applying this method to an alcoholism dataset, we found that flexible patterns of susceptible SNP combinations do play a role in complex diseases, and some known genes were detected through these risk SNP modules. One example is GRM7, a known alcoholism gene successfully detected by a SNP module comprised of two SNPs, but neither of the two SNPs was significantly associated with the disease in single-locus analysis. These identified genes are also enriched in some pathways associated with alcoholism, including the calcium signalling pathway, axon guidance and neuroactive ligand-receptor interaction. The integration of network biology and genetic analysis provides putative functional bridges between genetic variants and candidate genes or pathways, thereby providing new insight into the aetiology of complex diseases. 相似文献
77.
Ma YM Tao RY Liu Q Li J Tian JY Zhang XL Xiao ZY Ye F 《Molecular and cellular biochemistry》2011,357(1-2):65-72
PTP1B is a negative regulator of insulin signaling pathway. This study investigated the effects of compound CCF06240, a PTP1B inhibitor, on insulin sensitivity and lipid metabolic abnormalities in vivo and in vitro, respectively. The insulin resistant IRM mouse model was induced by HFD. The responses to insulin were determined by OGTT, ITT, and hyperinsulinemic-euglycemic clamp test. The body weight and the levels of serum TC and TG were measured to estimate the lipid metabolism in vivo. Recombinant human GST-PTP1B protein was used to measure the inhibition of CCF06240 on PTP1B activity. The hepatocyte lipid accumulation was induced by high concentrations of FFA and insulin in HepG(2) cells, and evaluated by the Oil Red O method. In IRM mice, the insulin resistance was improved; the body weight and the levels of TC and TG were also reduced by oral CCF06240 administration. In lipid accumulated model cells, CCF06240 was found to reverse the increased PTP1B activity, enhance the insulin-induced tyrosine phosphorylation in insulin signaling pathway, attenuate the FFA-insulin-induced cellular lipid accumulation, and down-regulate the expressions of genes related fatty acid synthesis. These results demonstrated that the PTP1B inhibitor, compound CCF06240, could increase insulin sensitivity through the regulation of insulin signaling pathway, and decrease FFA-insulin-induced hepatocytes lipid accumulation by reducing fatty acid syntheses. 相似文献
78.
同步辐射圆二色谱与普通圆二色谱相比,特点在于向真空紫外波段(〈200nm)拓展,以及同步辐射所提供的高强度紫外和真空紫外光源。糖的圆二色谱结构主要在200nm以下。蛋白质和核酸在200nm以下的真空紫外范围,也具有丰富的光谱结构。因此向真空紫外拓展,伴随新的电子跃迁,对应新的光谱结构,包含更丰富的结构信息,确定的结构种类就越多和越精确。同步辐射高强度的真空紫外光源,是获得高质量真空紫外圆二色谱数据的保证,为糖及糖蛋白、蛋白质和核酸研究提供了溶液中结构探测新的实验方法。综述同步辐射圆二色谱特点及其在结构生物学中的应用,以及新发展的蛋白质圆二色谱数据库(PCDDB)。介绍已对外开放的北京同步辐射实验室同步辐射圆二色谱探测,及其在蛋白质、糖和核酸研究中的应用,以及基于微流控混合芯片的亚毫秒动态探测发展。 相似文献
79.
The C21-steroidal glycoside auriculoside A (1), recently isolated from the roots of Cynanchum auriculatum, was found to inhibit the growth of several human tumor cell lines and to induce apoptosis in human breast cancer (MCF-7) cells. Compound 1 was evaluated for its in vitro cytotoxicity against MCF-7, HO-8910, and Bel-7402 cells, and for its in vivo antitumor effects on implanted sarcoma-180 (S180) tumors in mice. It showed significant, concentration-dependent inhibition of the cancer cells, both in vitro and in vivo. MCF-7 Cells exposed to 1 displayed typical morphological apoptosis characteristics such as cytoplasm contraction and nuclear-chromatin condensation. Flow-cytometric analysis showed that the MCF-7 cell cycle was arrested at the G0/G1 phase. When treated with 40 microg/ml of 1 for 24, 48, and 72 h, respectively, the apoptotic rates of the cells were ca. 5, 8, and 18.5%, respectively. 相似文献
80.