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51.
Mayne M Moffatt T Kong H McLaren PJ Fowke KR Becker KG Namaka M Schenck A Bardoni B Bernstein CN Melanson M 《European journal of immunology》2004,34(4):1217-1227
DNA microarray profiling of CD4(+) and CD8(+) cells from non-treated relapsing and remitting multiple sclerosis (MS) patients determined that the cytoplasmic binding partner of fragile X protein (CYFIP2, also called PIR121) was increased significantly compared to healthy controls. Western analysis confirmed that CYFIP2 protein was increased approximately fourfold in CD4(+) cells from MS compared to inflammatory bowel disorder (IBD) patients or healthy controls. Because CYFIP2 acts as part of a tetrameric complex that regulates WAVE1 activation we hypothesized that high levels of CYFIP2 facilitate T cell adhesion, which is elevated in MS patients. Several findings indicated that increased levels of CYFIP2 facilitated adhesion. First, adenoviral-mediated overexpression of CYFIP2 in Jurkat cells increased fibronectin-mediated adhesion. Secondly, CYFIP2 knock-down experiments using antisense oligodeoxynucleotides reduced fibronectin-mediated binding in Jurkat and CD4(+) cells. Thirdly, inhibition of Rac-1, a physical partner with CYFIP2 and regulator of WAVE1 activity, reduced fibronectin-mediated adhesion in Jurkat and CD4(+) cells. Finally, inhibition of Rac-1 or reduction of CYFIP2 protein decreased fibronectin-mediated adhesion in CD4(+) cells from MS patients to levels similar to controls. These studies suggest that overabundance of CYFIP2 protein facilitates increased adhesion properties of T cells from MS patients. 相似文献
52.
The increased incidence of thyroid carcinomas in familial adenomatous polyposis (FAP) patients is well recognised. These thyroid neoplasms display distinctive clinicopathological features and generally show good prognostic outcome. Recently, unusual sporadic tumours that share the morphological features of FAP-associated thyroid carcinomas have also been described. In this report, we document a case of a thyroid tumour in a previously well, 46-year-old female. Histology revealed a circumscribed neoplasm composed of tubular, papillary, cribriform and solid areas. The pseudostratified columnar tumour cells showed occasional nuclear grooves and rare nuclear inclusions. Immunohistochemistry showed positive staining with antibodies to cytokeratin AE1/AE3, oestrogen and progesterone receptor proteins. Focal immunoreactivity was also noted with antibodies to thyroglobulin, epithelial membrane antigen, 34betaE12 and cytokeratin CK7. The absence of polyps on colonoscopy and germline mutation in the adenomatous polyposis coli (APC) gene provides evidence that this tumour represents the sporadic counterpart of FAP-associated thyroid carcinoma. The patient is well with no evidence of disease 7 months following resection of the tumour. The differential diagnoses and molecular genetics of this unusual tumour are discussed. 相似文献
53.
抗T细胞单克隆抗体对再生障碍性贫血患者TNF和IL—2水平的影响 总被引:2,自引:0,他引:2
为探讨抗T淋巴细胞克隆抗体对再生障碍性贫血患者免疫功能的调节作用,采用放射免疫检测25例AA患者McAb-T治疗前后血清肿瘤坏死因子和白细胞介素-2(IL-2)水平及其中10例周围血单个核细胞体外诱生TNF和IL-2水平的变化。 相似文献
54.
本文采用放射性同位素标记的方法研究了嵌段聚醚型聚氨酯在纯纤维蛋白原溶液中和稀释血浆中的表面纤维蛋白原吸附性规律,考察了聚醚型聚氨酯的特性粘数及溶液体系中的NaCl浓度对材料表面纤维蛋白原吸附性的影响,结果表明,随着聚合物特性粘数的增大,材料表面的纤维蛋白原吸附量呈降低的趋势;溶液体系中盐浓度的降低导致纤维蛋白原凝固性增强,在纯纤维蛋白原溶液中,材料表面纤维蛋白原的吸附量相应增多,而在稀释血浆中,纤维蛋白原的吸附量相应减少,在达到最低值后又有上升的趋向,表明纤维蛋白原在材料表面的吸附还受血浆中其它大分子的影响。 相似文献
55.
Effect of biologically active coating on biocompatibility of Nitinol devices designed for the closure of intra-atrial communications 总被引:5,自引:0,他引:5
Kong X Grabitz RG van Oeveren W Klee D van Kooten TG Freudenthal F Qing M von Bernuth G Seghaye MC 《Biomaterials》2002,23(8):1775-1783
Anti-thrombogenicity and rapid endothelialisation are prerequisites for the use of closure devices of intra-atrial communications in order to reduce the risk of cerebral embolism. The purpose of this study was therefore to assess the effect of bioactive coatings on biocompatibility of Nitinol coils designed for the closure of intra-atrial communications. Nitinol coils (n = 10, each) and flat Nitinol bands (n = 3, each) were treated by basic coating with poly(amino-p-xylylene-co-p-xylylene) and then coated with either heparin, r-hirudin or fibronectin. Anti-thrombogenicity was studied in vitro in a dynamic model with whole blood by partial thromboplastin time (PTT), platelet binding and thrombin generation, respectively, and cytotoxicity by hemolysis. Endothelialisation was studied on Nitinol bands with human umbilical venous endothelial cells (HUVEC) by 3-(4,5-dimethylthiazole-2yl)-2,5-triphenyl tetrazolium (MTT) assay and immnuofluorescence analysis of Ki67, vinculin, fibronectin and von Willebrand Factor. Uncoated or coated devices did not influence hemolysis and PTT. r-Hirudin (but not heparin) and fibronectin coating showed lower platelet binding than uncoated Nitinol (p < 0.005, respectively). Heparin and r-hirudin coating reduced thrombin formation (p < 0.05 versus Nitinol, respectively). HUVEC adhesion, proliferation, and matrix formation decreased in the order: fibronectin coating > uncoated Nitinol > r-hirudin coating > heparin coating > basic coating. MTT assay corroborated these findings. In conclusion, r-hirudin and fibronectin coating, by causing no acute cytotoxicity, decreasing thrombogenicity and increasing endothelialisation improve in vitro biocompatibility of Nitinol devices designed for the closure of intra-atrial communications. 相似文献
56.
Stereoselective determination of cetirizine and studies on pharmacokinetics in rat plasma 总被引:2,自引:0,他引:2
Choi SO Lee SH Kong HS Kim EJ Choo HY 《Journal of chromatography. B, Biomedical sciences and applications》2000,744(1):201-206
Enantiomers may confer benefits over racemates in therapeutic uses and we developed a chiral separation method of cetirizine enantiomers, a second generation H1 histamine receptor antagonist, in rat plasma. alpha1-Acidglycoprotein based chiral stationary phase(AGP-CSP), monitored with UV at 230 nm was used to separate the enantiomers. Observed enantioselectivity (alpha) was 2.0. The AGP-CSP was also used at a preparative scale to isolate the enantiomers with an optical purity of greater than ee 99%. In addition, an analysis was carried out for the cetirizine enantiomers in rat plasma to study the differences of enantiomers in pharmacokinetics. Both (+)- and (-)-cetirizine were separated using a reversed-phase column of AGP, and were detected at the range of 2.5-200 microg ml(-1) in plasma. Although there was no recognizable differences in pharmacokinetics between the enantiomers in rat, the method appears to be useful for their pharmacokinetic studies. 相似文献
57.
运用敏感的B_9细胞增殖试验检测了81例多发性骨髓瘤(MM)患者血清IL-6活性,同时分析了标本的几种急性相蛋白含量,结果表明,68%MM患者血清中IL-6活性大于5μ/ml(正常对照为5μ/ml以下),几种急性相蛋白中C-反应性蛋白(CRP)在MM时升高(P<0.01),平均达正常对照组的17倍以上,MM患者补体C_4与正常对照组无差异(p>0.05),C_3、白蛋白及转铁蛋白在MM时分别比正常下降24.42%、38.83%和32.80%,且与疾病分期有关,在血清IL-6大于5μ/ml的55例中,IL-6活性与CRP、C_3、白蛋白的相关系数分别为0.46,-0.34和-0.29,IL-6与转铁蛋白浓度相关不明显。本文结果提示:CRP、C_3及白蛋白等含量的变化可作为反映MM病情的简易而敏感的指标。 相似文献
58.
氧分压在体监测仪的研制 总被引:2,自引:0,他引:2
作者报道一种稳定性较高的氧分压在体监测,为医学研究、临床诊断提供一种新的可靠的测试方法及设备,具有较大的应用价值。 相似文献
59.
本实验用HRP法、WGA—HRP法和ARG法进一步研究了大白鼠前脑、脑干和小脑向孤束核的纤维投射及其局部定位关系。作者发现皮质32及8区、三叉神经脊束核尾侧亚核投射到孤束核头段;皮质24及8a区、三叉神经脊束核尾侧亚核投射到孤束核中段;皮质23及13区,中脑导水管周围灰质和三叉神经脊束核尾侧亚核投射到孤束核尾段。此外,结果还证明室旁核、下丘脑外侧区、兰斑核、K—F氏核、小脑顶核、中缝大核、网状大细胞核、外侧网状核、及延髓网状结构向孤束核的纤维投射,均存在着一定的局部定位关系。本文结合前脑、脑干向孤束核的纤维投射讨论了内脏活动调节及针刺镇痛效应的中枢机理并对大白鼠孤束核的分段(头、中及尾段)标准提出了新建议。 相似文献
60.
G.-Y. Wang B. Sun Q.-F. Kong Y. Zhang R. Li J.-H. Wang D.-D. Wang G. X. Lv & H.-L. Li 《Scandinavian journal of immunology》2008,68(6):589-597
Interleukin (IL)-17 is a proinflammatory cytokine primarily secreted by Th17 cells, which are a CD4+ T-cell subset. Th17 cells and IL-17 are important in the pathogenesis of multiple sclerosis and in its established animal model, experimental autoimmune encephalomyelitis (EAE). However, it is unclear whether IL-17 contributes to EAE immune tolerance. We used the myelin basic protein (MBP) peptide MBP 68–86 to induce nasal tolerance to EAE, and simultaneously interfered with the tolerance by treatment with different doses of IL-17. We found that IL-17 dramatically interfered with MBP 68–86-induced immune tolerance. IL-17 administration increased IL-6 release, skewing T cell differentiation towards Th17 cells and decreasing the number of Treg cells. This led to an imbalance between Treg cells and Th17 cells and spurred the development of EAE. 相似文献