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71.
Recently, evidence has been presented for a possible association between hepatitis C virus (HCV) infection and essential mixed cryoglobulinemia (EMC). Eleven consecutive patients with EMC and two with cryoglobulinemia type I were examined for the presence of markers of HCV infection. Eleven of 13 patients (10 with EMC and 1 with type I cryoglobulinemia) had anti-HCV antibodies (as determined by a second generation anti-HCV assay) and HCV-RNA in plasma or serum. HCV-RNA was also detected in liver biopsies of five patients. Genotyping showed that HCV genotype 1 was found in 10 of 11 patients with HCV-RNA (9 genotype 1b and 1 genotype 1a) and only one patient had HCV genotype 2. However, a similar high prevalence of genotype 1b (100%) was found in a group of 14 consecutive patients with chronic hepatitis C, who had no clinical evidence of cryoglobulinemia. Concomitant infection was present in three patients with genotypes 2, 3 and 4, respectively. These findings stress the high prevalence of HCV infection in patients with EMC and further study shows that a difference in genotype prevalence was not found between HCV-related EMC and chronic hepatitis C without clinical manifestations of EMC. © 1994 Wiley-Liss, Inc.  相似文献   
72.
目的:为探讨胃癌组织p53、c-erbB-2、p21、nm23联合基因表达产物对胃癌诊断与治疗方面的价值。方法:应用免疫组化技术检测了手术切除胃癌组织p53、c-erbB-2、p21、nm23基因产物表达。结果:p53蛋白表达阳性率37.6%-46.2%,c-erbB-2为34.6%-56.8%,p21为37.8%。61.5%,nm23为30.8%-70.3%;非胃癌组织(胃、十二指肠溃疡、胃息肉、重度不典型增生)未见c-erbB-2、p21、nm23基因表达。c-erbB-2、p21的表达与胃癌的分化程度有关,p21、nm23基因表达与肿瘤浸润深度、肿瘤转移程度有关。p53、c-erbB-2、p21、nm23四种肿瘤蛋白在胃镜活检标本和手术切除标本中表达是一致的,无显著性差异。结论:对胃癌组织检测p53、c-erbB-2、p21、nm23基因表达产物在胃部的良恶性肿瘤鉴别、非手术临床分期的判断及指导胃癌的临床诊断与治疗等方面具有一定价值。  相似文献   
73.
The YWK-II cDNA, RSD-2, encoding a sperm membrane protein was isolated from a rat testis cDNA expression library. Using the RSD-2 insert in combination with rapid amplification of cDNA ends (RACE), the corresponding human gene was isolated from a human testis cDNA expression library. The human testis cDNA, HSD-2, is 3654 bp in length and contains an open reading frame of 763 codons. Hydropathicity analysis showed that the deduced polypeptide is a single strand transmembrane protein. The deduced polypeptide has partial homology with the amyloid precursor protein (APP) and high homology with the amyloid precursor homologue, APLP2/APPH. The YWK-II gene was mapped and assigned to human chromosome locus: 11q24-25. Northern blotting of various human tissue RNAs using the HSD-2 cDNA as a probe showed that the gene is transcribed ubiquitously. The cytoplasmic domain of HSD-2 was expressed in Escherichia coli. In-vitro studies showed that the recombinant polypeptide bound to a GTP-binding protein (G(o)) and was phosphorylated by protein kinase C and cdc2 kinase. In mammalian F11 cells, the recombinant polypeptide was found to be coupled to G(o). Thus, the YWK-II component has the characteristics of a G(o)-coupled receptor and may be involved in G(o)-mediated signal transduction pathway. Protein kinase C and cdc2 kinase may regulate this pathway in spermatozoa by phosphorylating the cytoplasmic domain of the YWK-II component.  相似文献   
74.
The pathological mechanism of SARS-CoV infection was investigated. The gene for the SARS-CoV non-structural protein 10, which is located in the open reading frame of pp1a/pp1ab gene, was synthesized and used to screen for the specific cellular gene coding for the protein interacting with this nsp10 protein in a human embryo lung cDNA library using a yeast trap method. The results indicated that apart from the two subunits of cellular RNA polymerase complex, BTF3 and ATF5, this nsp10 protein was also able to interact specifically with the NADH 4L subunit and cytochrome oxidase II. Further study revealed that the activity of the NADH-cytochrome was altered and the inner mitochondrial membrane was depolarized in the transfected human embryo lung fibroblast by the nsp10 protein gene. The cytopathic effect of the Coronavirus 229E strain appeared more extensive in these cells than in the control cells.  相似文献   
75.
广东汉族人β2-肾上腺素能受体基因Gln27Glu多态性   总被引:2,自引:0,他引:2  
目的 探讨β2-AR 16位点基因多态性在广东汉族人群中的分布.方法 应用聚合酶链反应技术对122例正常人β2-肾上腺素能受体基因Gln27Glu进行扩增并进行图谱分析.并结合文献进行了不同种族间的分析比较.结果 广东汉族人群β2-AR基因27位点多态性分布频率:Gln/Gln基因型占36.88%,Gln/Glu基因型占52.46%,Glu/Glu基因型占10.66%.结论 广东汉族人群存在出β2-AR Gln27Glu基因多态性,其分布频率与英美高加索人群有一定差异.  相似文献   
76.
目的:观察饮食诱导的胰岛素抵抗(IR)大鼠骨骼肌中糖原合成酶-3(GSK-3)及核糖体S6蛋白激酶(P70S6K)的表达及变化情况,并探讨GSK-3和P70S6K在IR发生中的作用及意义.方法:将40只4周龄Wistar大鼠随机分为正常对照组、高糖组、高脂组、高脂高糖饲养组,喂养8周后用高胰岛素-正葡萄糖钳夹技术(钳夹试验)对大鼠进行胰岛素敏感性的评估,采用Western blot法检测各组大鼠骨骼肌中GSK-3及P70S6K的含量,同时测定各组大鼠的附睾脂肪垫重量、血糖(BG)、胰岛素(INS)、甘油三酯(TG)、胆固醇(TC)及游离脂肪酸(FFA)水平、超敏C反应蛋白(hsCRP).结果:高脂高糖组、高脂组大鼠产生明显IR,体重增加(P<0.01),以附睾脂肪垫的重量增加更为显著(P<0.01),TG、TC及FFA水平、hsCRP增加(P<0.01),GSK-3、P70S6K在IR大鼠肌肉中的表达明显升高.结论:高脂高糖饮食可诱导大鼠产生IR,IR大鼠的hsCRP、TG、TC及FFA水平明显增高,大鼠产生IR与炎症反应有关,GSK-3、P70S6K在IR大鼠中的表达明显升高,在胰岛素信号传导中起负相调节作用.  相似文献   
77.
XRCC1、hOGG1基因多态性与喉癌遗传易感性的关系   总被引:1,自引:0,他引:1  
目的 探讨X线修复交叉互补组1基因(X-ray repair cross complementing group 1,XRCC1)、8-羟基鸟嘌呤修复酶基因(human 8-oxoguanine glycosylase I,hOGG1)多态性与喉癌遗传易感性的关系.方法 采用病例-对照设计,应用聚合酶链反应-限制性片段长度多态性分析法检测了72例经病理确诊的喉癌患者和随机抽样的72例无肿瘤、无遗传病对照者XRCC1-Arg399Gln、hOGG1-Ser326Cys多态性.结果 病例组XRCC1第399位密码子杂合型(Arg/Gln)及突变型(Gln/Gln)和hOGG1第326位密码子杂合型(Ser/Cys)及突变型(Cys/Cys)分布频率均高于对照组(P<0.05),与携带XRCC1-399野生型(Arg/Arg)、hOGG1-326野生型(Ser/Ser)个体相比,携带该基因型的个体喉癌的发病风险分别升高了3.37和2.54倍.交互作用分析显示,吸烟组与不吸烟组相比,携带XRCC1、hOGG1各基因型的个体的喉癌发病风险差异未发现存在统计学意义(xH12=0.15,xH22=0.28,P>0.05).结论 XRCC1-399位点Arg→Gln和hOGG1-326位点Ser→Cys的氨基酸替换可能导致喉癌的发病风险增加,XRCC1-Arg399Gln、hOGG1-Ser326Cys多态性可能与喉癌的遗传易感性有关.  相似文献   
78.
beta(2)-Glycoprotein I (beta(2)GPI) is a principal target antigen for antiphospholipid antibodies associated with recurrent pregnancy loss and fetal growth restriction in women. The significance of disrupted beta(2)GPI activity in contributing to pregnancy pathology in antiphospholipid syndrome (APS) is not clear. In this study the physiological requirement for functional beta(2)GPI in pregnancy was investigated by evaluating reproductive outcomes in beta(2)GPI null mutant (beta(2)GPI-/-) mice. beta(2)GPI-/- mice were fertile and carried viable fetuses to term. However, there was an 18% reduction in the number of viable implantation sites in beta(2)GPI-/- mice and reduced fetal weight and fetal:placental weight ratio in late gestation, suggesting compromised placental function. Placental architecture was altered in beta(2)GPI-/- implantation sites with a 24% increase in the junctional zone: labyrinthine ratio, but placentae showed no evidence of increased thrombosis in the absence of beta(2)GPI. The effect of beta(2)GPI genotype on pregnancy success after passive transfer of human and mouse antibodies reactive with beta(2)GPI was also explored. Two of five anti-beta(2)GPI antibodies induced pregnancy loss in beta(2)GPI+/+ mice but beta(2)GPI-/- mice were refractory to antibody-induced pregnancy failure. We conclude that functional beta(2)GPI is not essential for successful pregnancy in mice, but optimal placental development and fetal growth require this molecule. Together these data are consistent with pathogenic mechanisms in antiphospholipid syndrome involving both neutralization of beta(2)GPI function and beta(2)GPI-immunoglobulin complex formation.  相似文献   
79.
80.
Wong HT  Cheng SC  Chan EW  Sheng ZT  Yan WY  Zheng ZX  Xie Y 《Virology》2000,278(1):27-35
VP1 is a capsid protein of foot-and-mouth disease virus (FMDV) and contains epitopes of the virus. Plasmids encoding two VP1 epitopes (amino acid residues 141-160 and 200-213) and a host-self immunoglobulin molecule were constructed to produce a new type of FMD DNA vaccine. Two plasmids, namely, pCEIM and pCEIS, containing mouse immunoglobulin (IgG) or swine IgG were subjected to immunogenicity testing in mice and swine, respectively. In mice administrated pCEIM in the abdomen using a genegun, both FMDV-specific T-cell proliferation and neutralizing antibodies were detected. In swine immunized with pCEIS at the back of the ear, immune responses were achieved after the second administration. Swine showed a T-cell proliferative response with a stimulation index (SI) of up to 8.1 and a neutralizing antibody response that was able to protect suckling mice from 10(2) LD(50) (lethal dose 50) FMDV challenge. To compare the immunogenicity of the DNA-based vaccine candidate, versus the protein-based vaccine candidates, a second group of swine was immunized with the protein F1-scIgG, which was encoded by the plasmid pCEIS. Injection with F1-scIgG elicited a T-cell proliferative response of SI < 1.7 and a neutralizing antibody response that protected suckling mice from up to 10(5) LD(50) FMDV challenge. In the challenge test, three of three swine immunized with pCEIS were fully protected from FMDV challenge.  相似文献   
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