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991.
目的 在单细胞水平上,研究类风湿性关节炎(RA)患者滑液及外周血中T淋巴细胞上CCR5及CXCR3的表达,并结合临床资料分析其在RA发病中的可能作用机制及临床应用。方法 分离15例RA患者的滑液单个核细胞(SFMC)、外周血单个核细胞(PBMC),及15正常人PBMC(对照),以三色荧光素标记物进行流式细胞术分析T细胞上CCR5及CXCR3的表达。结果 与PBMC相比较,RA患者SFMC中T细胞上CCR5及CXCR3的表达显著增高(特别是CCR5);而CXCR3的表达个体差异较大;与正常人相比较,RA患者初发或活动期未治时,PBMC中CCR5及CXCR3的表达明显增多。CCR5及CXCR3的表达率与患者的ESR及CRP相关。结论 CCR5^ T细胞积聚在RA患者的病变关节内,且与RA的病情密切相关。  相似文献   
992.
Summary Administration of synthetic human corticotropin-releasing factor (hCRF, 2 µg/kg body weight) during simultaneous application of the opioid antagonist naloxone (1.6 mg i.v. bolus, followed by an infusion at a rate of 1.2 mg/h) produced a significant increase in plasma C-peptide levels of six male Type 2 diabetic patients which even exceeded the postprandial values. This stimulatory effect of hCRF/naloxone on plasma C-peptide was less pronounced in six healthy men. hCRF alone did not provoke any reaction of plasma C-peptide in either group.The possibility of a paracrine, CRF-dependent mechanism in pancreatic islets which somehow involves inhibitory opioid receptors is preferentially discussed. Such a mechanism may underlie the stimulatory action of hCRF/naloxone on B cells and would explain the absent reaction of peripheral venous plasma C-peptide to hCRF alone as well as the amplifying effect of simultaneous opioid receptor blockade.Abbreviations ACTH adrenocorticotropic hormone - C-peptide connecting-peptide - CRF corticotropin-releasing factor - hCRF human CRF - oCRF ovine CRF - min minutes - S.D. standard deviation - S.E.M. standard error of the mean This study was supported by the Deutsche Forschungsgemeinschaft (Go 299/3-2)Dedicated to Professor Dr. N. Zöllner on the occasion of his 65th birthday  相似文献   
993.
R Cigén 《Molecular immunology》1985,22(9):1039-1043
The structural difference between two forms (basic and acidic) of guinea-pig beta 2-microglobulin (beta 2m) has been established. Both forms are present in urine from inbred guinea-pig strains. The beta 2m forms were each digested with carboxypeptidase Y and carboxypeptidase A contaminated with carboxypeptidase B. Released amino acids were separated from remaining protein, dansylated and analysed by 2-dimensional TLC on polyamide layer sheets. From the results it was concluded that the basic beta 2m form has lysine and the acidic beta 2m form has asparagine as their respective C-terminal amino acids. The acidic form is also 1 amino acid (lysine) shorter than the basic form, which is supported by electrophoretic studies on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The presence of the 2 forms of beta 2m in urine from inbred guinea-pig strains 2 and 13, shown by gel filtration and ion exchange chromatography, makes it unlikely that the 2 forms are a result of genetic polymorphism.  相似文献   
994.
The in vivo effects of anticonvulsants on specific binding of [3H]GABA in the rat brain were examined in male Wistar rats. Acute treatment with phenobarbital increased specific [3H]GABA binding in the cerebral cortex, whereas repeated treatment with phenobarbital failed to change [3H]GABA binding. [3H]GABA binding in the cerebellum was not influenced by phenobarbital administration. Acute treatment with phenytoin produced no change in [3H]GABA binding, whereas repeated treatment with phenytoin caused a significant increase in [3H]GABA binding in the cerebellum, but not in the cerebral cortex. The effects of these anticonvulsants may be due, at least in part, to GABA receptor-mediated mechanisms.  相似文献   
995.
Mouse peritoneal M phi and human blood monocytes were assayed for their antitumor activity in vitro with a cytolysis, a cytostasis and a cytotoxicity test performed in parallel. Both natural and stimulus-induced M phi antitumor capacities were assessed. Results indicate that natural cytolytic activity of unstimulated M phi is generally unable to restrict final tumor cell growth, since it is not coupled with cytostatic capacity. In contrast, exposure of M phi in vitro to either MAF or IFN-beta, besides augmenting M phi cytolytic capacity, induced a very significant cytostatic activity and thus efficiently restricted the survival of tumor cells.  相似文献   
996.
The baculovirus expression system has been widely used to produce the capsid proteins of Norovirus (NV) and the proteins form virus-like particles (VLPs) that are useful in many studies, such as immunology, diagnosis, and host-receptor interaction. We report here the application of the E. coli expression system in the production of recombinant NV capsid proteins. In a direct comparison of a previous well-characterized NV strain (VA387), we have demonstrated that the E. coli-expressed capsid proteins maintain the same antigenicity and receptor binding specificity as that of the baculovirus-expressed capsid, although the E. coli-expressed VA387 proteins did not form VLPs. Using the E. coli-expression system, we characterized the receptor-binding patterns of three additional NV strains (OIF1998, Parris Island and VA115), in which OIF1998 binds to HBGA of nonsecretors but did not bind or binds weakly to the HBGA of secretors, as seen in strain VA207. Parris Island binds to HBGA of types A and B but not type O secretors and nonsecretors. VA115 did not show specific binding to any A, B, O secretor nor nonsecretor, which is also observed when the capsid protein of this strain was expressed in baculovirus. Our data indicate that VLP formation is not required for receptor binding, and that the bacteria expression system offers a simple alternative for large production of NV capsid protein for various research purposes, particularly for strains generating low yields in the insect cells.  相似文献   
997.
LPS对MRL/MpJ小鼠脾T细胞表达TLR4和TNFα的影响   总被引:1,自引:0,他引:1  
研究Toll样受体 4 (TLR4 )在MRL/MpJ小鼠脾细胞的表达状况和革兰阴性菌脂多糖 (LPS )刺激后TLR4的表达变化以及对TNF α产生的影响。MRL/MpJ小鼠经腹腔注射LPS后在不同时间取脾细胞 ,用三色荧光标记流式细胞仪技术检测小鼠脾T细胞TLR4的表达情况 ,并与BALB/c小鼠作对照 ;通过RT PCR观察LPS刺激前后脾T细胞TNF αmRNA的表达变化。结果表明TLR4在MRL/MpJ小鼠CD3+ CD4 + T细胞和CD3+ CD8+ T细胞中均有表达 ;但TLR4 + /CD4 + 细胞表达仅BALB/c小鼠的 33% ,在受LPS刺激后 ,MRL/MpJ鼠CD4 + T细胞TLR4升高时间较BALB/c小鼠延迟 ;CD8+ T细胞TLR4在LPS刺激前后无明显变化 ;脾细胞TNF αmRNA水平升高亦延迟。通过对干燥综合征样自身免疫病鼠模型MRL/MpJ小鼠脾T细胞TLR4的表达及功能研究 ,将有助于认识天然免疫和获得性免疫间的联系和感染在自身免疫病发病中的作用。  相似文献   
998.
TNF is a potent proinflammatory cytokine important for the development of arthritis in human and animals. We have investigated the roles of TNF receptor-1 (TNFR1) and TNF receptor-2 (TNFR2) in collagen-induced arthritis (CIA) by inducing CIA in mice genetically deficient in TNFR1. TNFR1-/- mice developed arthritis with similar incidence and severity as TNFR1+/- littermates, indicating that TNFR1 is redundant for the development of CIA. Anti-type II collagen (CII) antibody levels and T cell responses to CII did not differ between TNFR1-/- mice and controls. Neutralization of TNF with soluble TNF binding protein suppressed the development of arthritis in TNFR1+/- mice but not in TNFR1-/- mice, indicating that TNFR2 cannot substitute for TNFR1 for the proinflammatory function. To further investigate the functions of TNFR2, TNFR1-/- mice were injected with murine TNF-alpha at different stages during the course of CIA. Repeated TNF-alpha injection during the early induction phase enhanced the development of arthritis, but inhibited arthritis when administered during the late progression phase. These results show that the engagement of TNFR2 by TNF is involved in the development of CIA in the absence of TNFR1 and that opposing signals can be transduced by TNFR2.  相似文献   
999.
Most patients with cri-du-chat syndrome have a de novo deletion of the short arm of chromosome 5 (5p). In order to perform extensive phenotype-genotype correlation studies, a relatively easy method for the precise determination of the extent of a patient's deletion is essential. Towards this purpose, a set of minimally overlapping YAC clones that span 5p was identified. A BAC that maps at or near the 5p telomere was also used. A total of 110 patients with previously determined de novo terminal deletions by standard cytogenetic approaches were reanalyzed using the YAC clones and fluorescent in situ hybridization (FISH). Of the 110 samples, 4 patients were determined to have interstitial deletions, 1 patient had an unbalanced translocation, and no deletion could be detected in 2 patients. The FISH results in the 7 patients affect the clinical prognosis for some of these patients. These results demonstrate the need for supplementing standard cytogenetics with FISH analysis when an abnormal karyotype is detected.  相似文献   
1000.
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