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991.
Reduced levels of a soluble form of the adhesion receptor and CD2 ligand CD58 (sCD58) were previously described in RA patients. In order to understand the biological significance of this finding we biochemically characterized sCD58 in RA and asked how well sCD58 binds to CD2. sCD58 concentrations were measured in serum and synovial fluid (SF) samples of RA patients by two ELISAs, one detecting domain 1 of CD58 (CD58-D1), and the other one the complete molecule (CD58-D1 + D2). Small amounts of split sCD58-D1 were found in most RA sera, but not SF. In addition, split sCD58-D2 was detected in SF by affinity chromatography, SDS–PAGE, and Western blotting. Gel filtration gave similar peaks at 95–125 kD for RA sera, SF, and normal serum. Binding of SF-sCD58 to the CD2+ Jurkat variant JBB1 or recombinant CD2 was stronger than urinary sCD58 and reached binding of oligomeric recombinant CD58 at low concentrations. In conclusion, sCD58-split products were found in RA sera and SF. At concentrations as they occur in vivo, SF-sCD58 binds to CD2 much more strongly than urinary sCD58. It is conceivable that locally released sCD58 blocks the CD2/CD58 interaction under physiological conditions. Insufficient release of sCD58, e.g. in synovitis, might result in T cell accumulation and perpetuation of inflammation.  相似文献   
992.
Diagnosis of Yersinia infections accompanied by reactive arthritis could be complicated by cross-reaction with other arthritogenic bacteria. The possible cross-reaction between Yersinia antigens and anti- Borrelia antibodies in blood sera of patients with Lyme disease was studied. The occurrence of specific IgA, IgG and IgM antibodies was analyzed in serum samples from 30 patients with Yersinia -triggered reactive arthritis, 30 patients with Lyme disease and five samples from healthy blood donors. For anti- Borrelia IgG antibodies, cross-reaction was detected with YopH, YopB, V-ag, YopD, YopN, YopP and YopE, and for IgA with YopD. For IgM, no cross-reaction was detected. Owing to cross-reactivity with Borrelia , the diagnosis of Yersinia -triggered reactive arthritis should be based on a combination of serological and clinical findings.  相似文献   
993.
The Z39Ig protein (complement receptor for C3b and iC3b) is expressed on resident tissue macrophages in various tissues. This study was undertaken to examine the distribution of Z39Ig+cells and their phenotypic features in rheumatoid arthritis (RA) synovium, in comparison with those of osteoarthritis (OA) and psoriatic arthritis (PsA) synovium. Monoclonal anti-Z39Ig antibody was produced by immunizing Z39Ig transfected murine pre B cells and used for the identification of Z39Ig+cells. Z39Ig+cells were further stained with antibodies to macrophages, fibroblast-like synoviocytes, complement receptors and dendritic cells by using the double immunostaining method in normal, RA, OA and PsA synovium. RA synovial mononuclear cells were double-stained using anti-Z39Ig and anti-CD11c antibodies and sorted into Z39Ig+CD11c+cells and Z39Ig+CD11c-cells. These cell populations were then analysed by electron microscopy. The expression of the Z39Ig protein was limited to intimal macrophages in normal, RA, OA and PsA synovium. The numbers of Z39Ig+CD11c+cells and the ratios of Z39Ig+CD11c+cells to Z39Ig+cells were increased in the synovial lining layer of RA as compared with those of OA and PsA. The ultrastructural analysis of Z39Ig+CD11c+cells showed the character of macrophages with many secondary lysosomes and swelling of mitochondria. Z39Ig+ cells appeared to be useful for identification of resident tissue macrophages in normal synovium and the corresponding macrophages in the synovial lining layer of inflammatory arthritis. Expansion of Z39Ig+CD11c+cells was characteristic of RA synovial lining layer.  相似文献   
994.
目的:研究类风湿性关节炎(RA)患者血清游离脂肪酸(FFA)、高敏C-反应蛋白(hs-CRP)和肿瘤坏死因子(TNF-α)水平的变化及其与胰岛素抵抗的关系。方法:测定92例RA患者(稳定期53例,活动期39例)及50例正常人血清FFA、空腹胰岛素(fINS)、空腹血糖(fPS),同时检测hs-CRP、TNF-α、血脂等指标,并计算胰岛素敏感指数(ISI)、稳态模型胰岛素抵抗指数(Homa-IR),分析FFA水平的变化与胰岛素抵抗的关系。结果:非活动期和活动期RA患者,FFA、hs-CRP、TNF-α、Homa-IR、TG和LP(α)水平均较正常对照组显著升高(P〈0.05或P〈0.01),且活动期RA组FFA、hs-CRP、TNF-α、fINS、Homa-IR、TG和LP(α)水平较非活动期RA患者明显升高(P〈0.05或P〈0.01);直线相关分析显示,血清FFA水平与hs-CRP、TNF-α、fINS、Homa-IR、TG和LP(α)呈正相关(P〈0.01),与ISI呈负相关(P〈0.01)。结论:RA患者血清FFA水平明显升高,且与hs-CRP、TNF-α及胰岛素抵抗密切相关。  相似文献   
995.
目的:提高对以重症肝炎为首发症状的巨噬细胞活化综合征的认识。方法:对6例以重症肝炎为首发症状的巨噬细胞综合征的临床表现及实验室资料进行回顾性分析。结果:6例以重症肝炎为首发症状的巨噬细胞活化综合征的患儿均有幼年特发性关节炎(全身型)病史,MAS发病时均无发热,6例患儿的肝功能ALT平均为1 927.33 U/L,TBIL平均为179.82μmol/L,6例经治疗后肝功能均好转出院,无死亡病例。结论:对于重症肝炎的患儿,应综合分析,追问有无风湿性疾病的病史,尤其是幼年特发性关节炎(全身型)病史,提高对巨噬细胞活化综合征的认识,早期诊断,早期治疗。  相似文献   
996.
目的 探讨pre-miR-146a基因rs2910164位点单核苷酸基因多态性及miR-146a表达与类风湿关节炎相关性.方法 采用聚合酶链反应-连接酶检测反应检测123例类风湿关节炎(RA)患者和220例健康对照者pre-miR-146a rs2910164位点基因多态性,应用实时荧光定量聚合酶链反应检测68例RA患者、10例骨关节炎(OA)患者及20例健康对照外周血单个核细胞中miR-146a的表达水平,并选取10例RA疾病活动患者行激素加免疫抑制剂正规治疗3个月后miR-146a表达水平的测定.收集并计算RA患者临床参数:发病年龄、性别、类风湿因子(RF)和抗环瓜氨酸肽(抗-CCP)抗体、RA疾病活动(DAS28≥3.2)、骨破坏(X>Ⅰ期).统计学处理采用X2检验、方差分析、t检验和Pearson相关分析.结果 RA组pre-miR-146a rs2910164位点的基因型频率和等位基因频率与健康对照组比较,差异无统计学意义(P均>0.05).RA患者pre-miR-146ars2910164位点基因型与发病年龄、性别、RF和抗-CCP抗体阳性率、RA疾病活动、骨破坏阳性率及miR-146a表达量均无相关性(P均>0.05).RA患者组miR-146a的表达量高于健康对照组和OA组(P均<0.01),后两组miR-146a的表达量无统计学差异(P>0.05).RA疾病活动组miR-146a表达高于非活动组和对照组(P均<0.01),后两组miR-146a的表达量无统计学差异(P>0.05).RA疾病活动患者治疗后miR-146a表达下降(P<0.05),DAS28评分降低(P<0.01).RA患者组miR-146a的表达与红细胞沉降率(ESR,即血沉)、C反应蛋白(CRP)及DAS28评分之间呈正相关(P均<0.01),与RF、抗-CCP抗体滴度无相关性(P均>0.05).结论 我国汉族人群中,pre-miR-146a rs2910164位点多态性与RA的易感性、临床参数及miR-146a的表达无相关性,RA患者外周血单个核细胞miR-146a表达上调,其表达水平与RA病情活动有关,miR-146a的检测可能是RA病情活动的一个有用的判断指标.  相似文献   
997.
Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in children and adolescents. Immunomodulatory drugs are used frequently in its treatment. Using the nominal group technique (NGT) and Delphi method, we created a multidisciplinary, evidence- and consensus-based treatment guideline for JIA based on a systematic literature analysis and three consensus conferences. Conferences were headed by a professional moderator and were attended by representatives who had been nominated by their scientific societies or organizations. 15 statements regarding drug therapy, symptomatic and surgical management were generated. It is recommended that initially JIA is treated with NSAID followed by local glucocorticoids and/or methotrexate if unresponsive. Complementing literature evidence with long-standing experience of caregivers allows creating guidelines that may potentially improve the quality of care for children and adolescents with JIA.  相似文献   
998.
999.
目的 研究诱骗受体DcR3 对佐剂型关节炎(AA)大鼠模型的作用及其机理.方法 注射弗式完全佐剂建立大鼠佐剂型关节炎(AA)模型,尾静脉注射DcR3蛋白,观察大鼠关节肿胀度、间接 ELISA 检测血清和滑膜液中细胞因子IL-1 β、TNF-α、IFN-γ的变化.RT-PCR检测滑膜和淋巴细胞中DcR3、Fas、FasL mRNA的表达以及脾脏中TGF-β、IFN-γ、TNF-α、IL-4、IL-10 mRNA的表达.Western blot分析滑膜细胞中Caspase-8、Caspase-3、Caspase-9、Bcl-2蛋白的表达.结果 DcR3 治疗AA大鼠后,足肿胀度降低;血液和滑膜液的IL-1β、TNF-α、IFN-γ水平下降;脾脏中TGF-β、IFN-γ、TNF-α mRNA 表达下调,IL-4、IL-10 mRNA表达上调;滑膜细胞中Caspase-8、Caspase-3蛋白表达上调,Bcl-2蛋白表达下调. 结论 DcR3 可以用于实验性大鼠AA的治疗,其治疗机制与调节滑膜细胞FasL、Fas mRNA的表达和血液淋巴细胞中 Fas mRNA的表达,促进滑膜细胞和自身反应性淋巴细胞的凋亡;调节脾脏细胞Th1/Th2细胞因子平衡相关.本研究为进一步阐明RA的发病机理奠定了重要基础,为有效治疗RA提供了新思路.  相似文献   
1000.
In rheumatoid arthritis (RA) there are currently no useful indicators to predict a clinical response to tumour necrosis factor-alpha (TNF-alpha) blockade. The purpose of this study was to determine the role of peripheral blood cytokine profiling in differentiating between a good versus poor response to etanercept in RA. Peripheral blood samples were collected at baseline and at 3 months from 33 patients with active disease who were treated twice weekly by etanercept therapy. Responders are defined by the presence of three of four American College of Rheumatology criteria: > or =20% decrease in C-reactive protein (CRP), visual analogue score of disease activity, erythrocyte sedimentation rate and improvement of the disease activity score (28; four values) by > or =1.2 obtained at 3 months. Twelve cytokines were measured from serum collected on days 0 and 90 by proteomic array (protein biochip array, Investigator Evidence, Randox France), including interleukin (IL)-6, TNF-alpha, IL-1a, IL-1b, IL-2, IL-8, interferon-gamma, IL-4, IL-10, monocyte chemoattractant protein (MCP)-1, epidermal growth factor (EGF) and vascular endothelium growth factor. Our results showed that high serum levels of MCP-1 and EGF were associated with a response to etanercept. In addition, the increase of two combined parameters CRP and EGF was predictive of a response to etanercept treatment at 3 months (sensitivity: 87.5% and specificity: 75%, accuracy: 84.4%). These findings suggest that cytokine profiling by proteomic analysis before treatment initiation may help to identify a responder patient to TNF-alpha blocking agents in RA.  相似文献   
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