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目的用基因表达分析法鉴定丙型肝炎病毒(HCV)核心(Core,C)区基因插入突变体编码蛋白在人肝癌细胞系(Huh-7)表达,探讨该蛋白生物学功能及其基因表达改变与致病的关系。方法构建HCV-1bc基因插入突变体编码蛋白重组表达质粒,建立表达c基因插入突变体编码蛋白Huh-7细胞系,按Affymetrix公司实验程序制备探针、再与该公司H0u133A和Hg-u133b芯片杂交。对基因表达上调或下调≥3倍的基因,用NetAflk作进一步分析。并用半定量RT-PCR对其中3个上调基因进行鉴定。结果Microarray分析显示,HCV-1b C基因插入突变体编码蛋白比c蛋白引起更多的基因表达改变,主要集中在信号传导、蛋白酶活性、分子转运、免疫反应等,特别是免疫反应基因表达更加显著。C基因插入突变体编码蛋白表达可同时导致凋亡基因/抗凋亡基因表达上调或下调及致癌基因上调。半定量RT-PCR对有趣的致癌基因FHL2、抗凋亡基因PRKCZ和凋亡基因LGALSI的鉴定结果表明,FHL2、PRKCZ和LGALSI基因的表达比空载体转染对照组相同基因明显上调。结论Hcvc基因插入突变体编码蛋白在Huh-7细胞表达对其基因表达有很大影响,其中对免疫反应基因的影响更明显,这一结果对理解HCV C基因插入突变体编码蛋白在HCV致病过程中的作用及其研制抗HCV药物均有重大的参考价值。 相似文献
106.
目的 :检测胆囊癌组织中P6 2蛋白、碱性成纤维细胞生长因子(bFGF)的表达和微血管密度 (MVD) ,探讨它们的相互关系 ,以及与胆囊癌临床病理特征的关系。方法 :4 1例胆囊癌和 2 2例慢性胆囊炎组织中 ,P6 2蛋白和bFGF的表达用SP免疫组化染色法进行检测。胆囊癌组织中MVD用抗CD34单抗 (mAb)做SP免疫组化染色进行检测。结果 :4 1例胆囊癌组织中 ,P6 2和bFGF表达阳性率分别为 6 3.4 %和 75 .6 % ,均高于 2 2例慢性胆囊炎组织 (P <0 .0 1)。P6 2的表达与胆囊癌淋巴结转移有关 (P <0 .0 5 ) ,与癌组织的分级、临床分期无显著关系。bFGF的表达与胆囊癌临床病理分期及组织学分级有关 (P <0 .0 5 ) ,而与淋巴结转移无显著关系。P6 2表达率与bFGF表达率呈正相关关系 (r=0 .5 2 1;P <0 .0 1)。两者的表达均与患者的年龄、性别、肿瘤的种类、是否伴有胆囊结石无关。胆囊癌组织中MVD明显高于慢性胆囊炎组织 (P <0 .0 1)。P6 2及bFGF表达阳性组织MVD高于表达阴性组织 (分别P <0 .0 5和P <0 .0 1)。MVD与胆囊癌的Nevin分期及淋巴结转移有关 (P<0 .0 1) ,与患者的年龄、性别、肿瘤种类、分化程度以及是否伴有胆囊结石无关。结论 :P6 2蛋白及bFGF的表达与胆囊癌组织中血管的生成相关 ,在胆囊癌的发生和发展过程中可能具有重 相似文献
107.
Isolation of Nanjing local strains of HHV-7 and their biological and immunological characteristics 总被引:2,自引:0,他引:2
To investigate the biological and immunological characteristics of the Nanjing local strains of HHV-7,fourstrains of herpesvirus were isolated from saliva specimens of one healthy individual and three childrensuffering from a kidney disease in Nanjing.The viruses were identified by transmission electron microscopy(EM),indirect immunofluorescence assay(IFA) with a specific monoclonal antibody;nested polymerase chainreaction,restriction mapping and DNA sequencing.The virus-infected cells showed the typical cytophathiceffect(CPE) under microscopy and could be detected by IFA with the human herpesvirus-7(HHV-7) specificantibody.Under EM,herpesvirus-like and virions capsids could be found in their cytoplasm or nucleoplasm.HHV-7 DNA fragments amplified from infected cells by nested PCR were confirmed by restriction mappingand DNA sequencing.Similarly to DC strain,an known HHV-7 strain used in the present study as the positivecontrol,the virus could be inactivated by ultraviolet irradiation for 10 min,heated at 45℃ for 30 min,pH<5or>9 at 4℃ for 2 h and ether or chloroform for 10 h.The virus induced the production of TNF-α,IL-10 andIL-12p70 while inhibited IFN-γ secretion,increased the percentage of CD2~+ cells while decreased that of CD4~+or CD45RA~+ cells.The results indicate that the viruses isolated in Nanjing are HHV-7,which has similarbiological characteristic to the known HHV-7 strain,DC.Infection with HHV-7 in vitro could affect immunefunction of lymphocytes by disturbing cytokine production and CD antigen expression.Cellular & MolecularImmunology.2004;1(5):367-372. 相似文献
108.
He L Tang X Li N Wu YQ Wang JW Li JR Zhang ZX Dou HD Liu JJ Yu LP Xu HT Zhang JG Hu YH 《Maturitas》2012,72(2):132-138
Objectives
This study was to explore the independent influence of menopause on cardiovascular disease (CVD) and its risk factors in rural Chinese females.Study design
This cross-sectional population-based study enrolled 2245 premenopausal and 2498 postmenopausal women aged 40–59 years in Fangshan district, Beijing, China. Data was collected by face-to-face interview, physical examination and biochemical examination during 2009 and 2010. General liner models were employed to calculate age-adjusted means of cardiovascular risk factors (CRFs). The comparisons of CVD and it risk factors according to menopausal status, and calculation of adjusted odds ratios/coefficients and their 95% confidence intervals for the associations of quartiles of elapsed time since menopause and age at menopause with CVD and its risk factors was performed by multivariate logistic/liner regression models separately.Results
After adjustment for age and other confounders, no statistically significant association of menopause with CVD was observed in our participants; however, dyslipidemia prevalence and levels of waist-to-hip ratio, triglycerides, total cholesterol and low-density lipoprotein cholesterol were presented higher in postmenopausal group, compared to the premenopausal one (P < 0.05). Compared to women who had been menopausal for less than1 year, those with the elapsed time since menopause of 2–3 years had higher CHD prevalence, higher triglycerides level and lower high-density lipoprotein cholesterol level (P < 0.05).Conclusions
Postmenopausal women in rural China had worse CRFs profile than the premenopausal ones, which implied menopause might aggravate the CRFs epidemic beyond effects of aging, and would increase the CVD burden during and after their middle ages. 相似文献109.
The goal of this study was to investigate whether glycosylphosphatidylinositol (GPI)-anchored 6?kDa early secreted antigenic target (ESAT-6) and IL-21-producing B16F10/ESAT-6-GPI-IL-21 viable vaccine would induce antitumor efficacy. Mice were immunized with B16F10/ESAT-6-GPI-IL-21 vaccine and challenged by B16F10 cells 2?weeks later. Antitumor efficacy and mechanisms of the vaccine were analyzed. Vaccination with the viable B16F10/ESAT-6-GPI-IL-21 vaccine resulted in an increase of IFN-γ level and the CD8(+)CTL cytotoxicity, a decrease in TGF-β generation and increase in the expression of miR-200c that serves as melanoma suppressor by directly targeting zinc-finger E-box binding homeobox 1 to inhibit epithelial-mesenchymal transition and block tumor metastasis. The vaccine significantly inhibited the melanoma growth, reduced the lung melanoma nodules, and prolonged the mouse survival compared with the controls. These findings highlighted IL-21 as an immune adjuvant in an engineered viable tumor vaccine to reinforce heterogenetic antigen ESAT-6 immune tolerance break to induce powerful antitumor efficacy in mice. 相似文献
110.
Ying L Xu X Liu J Dou D Yu X Ye L He Q Gao Y 《Pflügers Archiv : European journal of physiology》2012,463(2):257-268
The present study was to determine the role of the type I isoform of cGMP-dependent protein kinase (PKG I) and its downstream
effector myosin phosphatase target subunit 1 (MYPT1) in the responses of different sized coronary arteries to nitrovasodilators.
Relaxations of isolated porcine coronary arteries were determined by isometric tension recording technique. Protein levels
of PKG I and its effectors were analyzed by Western blotting. The activities of PKG I and MYPT1 were studied by analyzing
phosphorylation of vasodilator-stimulated phosphoprotein (VASP) and MYPT1, respectively. Nitroglycerin, DETA NONOate, and
8-Br-cGMP caused greater relaxations in large than in small coronary arteries. Relaxations were attenuated to a greater extent
by Rp-8-Br-PET-cGMPS (a PKG inhibitor) in large vs. small arteries. The expressions of PKG I and MYPT1 in large arteries were
more abundant than in small arteries. DETA NONOate stimulated phosphorylation of VASP at Ser239 and inhibited phosphorylation
of MYPT1 at Thr853 to a greater extent in large than in small arteries. A suppressed phosphorylation of MYPT1 at Thr853 was
caused by 8-Br-cGMP in large but not small arteries, which was inhibited by Rp-8-Br-PET-cGMPS. These results suggest that
the greater responsiveness of large coronary arteries to nitrovasodilators result in part from greater activities of PKG I
and MYPT1. Dysfunction in nitric oxide signaling is implicated in the vulnerability of large coronary arteries to certain
disorders such as atherosclerosis and spasm. Augmentation of PKG I–MYPT1 signaling may be of therapeutic benefit for combating
these events. 相似文献