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151.
Adenosine decreases post-ischaemic cardiac TNF-alpha production: anti-inflammatory implications for preconditioning and transplantation. 总被引:1,自引:0,他引:1
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D R Meldrum B S Cain J C Cleveland Jr X Meng A Ayala A Banerjee A H Harken 《Immunology》1997,92(4):472-477
Tumour necrosis factor-alpha (TNF-alpha) is an autocrine contributor to myocardial dysfunction and cardiomyocyte death in ischaemia-reperfusion injury (I/R), sepsis, chronic heart failure and cardiac allograft rejection. Cardiac resident macrophages, infiltrating leucocytes, and cardiomyocytes themselves produce TNF-alpha. Although adenosine reduces macrophage TNF-alpha production and protects myocardium against I/R, it remains unknown whether I/R induces an increase in cardiac TNF-alpha in a crystalloid-perfused model (in the absence of blood), and, whether adenosine decreases cardiac TNF-alpha and protects function after I/R. To study this, isolated rat hearts were crystalloid-perfused using the Langendorff method and subjected to I/R, with or without adenosine pretreatment. Post-ischaemic cardiac TNF-alpha (enzyme-linked immunosorbent assay and bioassay) and function were determined (Langendorff). I/R increased cardiac TNF-alpha and impaired myocardial function. Adenosine decreased cardiac TNF-alpha and improved post-ischaemic functional recovery. This study demonstrates that: first, I/R induces an increase in cardiac tissue TNF-alpha in a crystalloid-perfused model: second, adenosine decreases cardiac TNF-alpha and improves post-ischaemic myocardial function; third, decreased cardiac TNF-alpha may represent a mechanism by which adenosine protects myocardium; and fourth, adenosine-induced suppression of cardiac TNF-alpha may provide an anti-inflammatory link to preconditioning and have implications for cardiac allograft preservation. 相似文献
152.
153.
Glycosyltransferases are involved in synthesis of various glycolipids and glycoproteins that play important roles in many biological processes. We have identified a zebrafish gene encoding a member of beta1,3-N-acetylglucosaminyltransferase family, the Lc3 synthase/bGn-T5. Whole-mount in situ hybridization reveals that the Lc3 synthase gene is expressed in two distinct phases during the zebrafish embryogenesis. The early phase extends from late blastulation to the completion of epiboly, during which the expression occurs in the superficial layer of the embryos. The second phase of expression starts during mid-segmentation and persists until day 3, during which the expression occurs prominently in the developing lens. The expression of the Lc3 synthase gene in the lens is inhibited in you-too (yot) mutant embryos that are defective in Hedgehog signaling. The expression in the lens also decreases in cyclops (cyc) and one-eyed-pinhead (oep) mutant embryos and lefty1-injected embryos, which are deficient in Nodal signaling and lack Hedgehog activity in the ventral brain. These results suggest that Hedgehog signaling is required for the Lc3 synthase expression in embryonic lens. 相似文献
154.
目的 评定旅游者的心理健康状况。方法 对我市某旅行社外出旅游者进行症状自评量表 ( SCL-90 )测试 ,并将结果与中国正常人常模进行比较。结果 旅游者在人际关系和焦虑两项因子分高于常模 ,其中人际关系敏感因子分差异显著( P<0 .0 5 ) ,精神病性因子分低于常模 ,并具有显著差异 ( P<0 .0 5 ) ;单独外出旅游者与结伴外出旅游者相比在人际关系敏感和焦虑两个因子方面具有显著性的差异 ( P<0 .0 5 )。结论 旅行社对旅游者的心理健康状况应引起重视 ,并对存在的心理问题进行必要的干预 相似文献
155.
我们利用兔抗微管蛋白抗体和兔抗辣根过氧化物酶(HRP)抗血清制备的HRP—抗HRP(PAP)复合物,建立了微管的PAP免疫酶细胞化学方法。应用此法观察到人食管癌ECa 109、胃癌SGC 7901,乳腺癌MCF 7和成骨肉瘤OS 732细胞间期胞质微管减少或消失,只有大量弥散分布的微管蛋白棕色反应产物,在微管组织中心(MTOC)附近十分密集,而正常成纤维细胞和胎儿胃粘膜上皮细胞间期,都有发达的胞质微管结构(CMTC)。在分裂期,这些肿瘤细胞都显示纺锤体微管,与正常细胞比较无明显差异。本研究应用PAP方法进一步证明,以前用免疫荧光细胞化学方法观察到的人肿瘤细胞间期胞质微管缺陷的特征。除去低温(4℃)或秋水仙酰胺处理后,解聚的CMTC又可恢复,表明本方法与免疫荧光染色法,同样具有很高的特异性。本工作在细胞固定及免疫反应的某些步骤上有所改进。 相似文献
156.
Autoimmunity to Spermatozoa and the Testis 总被引:2,自引:0,他引:2
157.
J chain deficiency in human IgM monoclonal antibodies produced by Epstein-Barr virus-transformed B lymphocytes 总被引:1,自引:0,他引:1
Six human IgM monoclonal antibodies against Pseudomonas aeruginosa were purified and characterized. On agarose-acrylamide sodium dodecyl sulfate (SDS) gels run under nonreducing conditions, IgM monoclonal antibodies showed variable amounts of a slower migrating form of IgM in addition to the one co-migrating with plasma IgM. Protein blotting with anti-J chain antibody showed that the slower migrating form did not contain J chain. Analysis of one of the monoclonal antibodies by sucrose gradient centrifugation showed that the J chain-deficient form sedimented faster than the complete IgM. It is known that IgM preparations lacking J chain sediment faster by sucrose gradient centrifugation analysis and tend to form hexamers. The slower migrating form of IgM we observed on SDS gels under nonreducing conditions could be hexameric IgM. Further evaluation of this monoclonal antibody demonstrated that both forms of IgM had the same antigen-binding activity. Glycosylation of the light chain was demonstrated in two of the monoclonal antibodies. 相似文献
158.
白细胞介素1,肿瘤坏死因子α和脂多糖对人脐静脉内皮细胞表达 … 总被引:5,自引:0,他引:5
目的 观察细胞因子白细胞介素1(IL-1)β、肿瘤坏死因子(TNF)α和脂多糖(LPS)是否诱导人脐静脉内皮细胞表达单核细胞趋化蛋白1(MCP-1)mRNA及蛋白。方法 选取生长汇合的人脐胸脉内皮细胞,在其培养基中分别加入终浓度为2ng/ml的IL-1β、20ng/ml的TNFβ和100ng/ml的LPS,37℃共育4h后,按照一步法提取其总RNA,用γ-^22P标记的寡核苷酸dot blot分析 相似文献
159.
目的:初步研究微小RNA-29b(mi R-29b)介导的TGF-β/Smad信号通路在肝星状细胞(HSC)活化中的作用及其对大鼠肝纤维化进程的影响。方法:构建肝纤维化大鼠模型并分离其HSC,同时通过体外获取并鉴定正常大鼠HSC。运用RT-qPCR和Western blot检测以上获取细胞中mi R-29b、TGF-β/Smad信号通路相关蛋白和肝纤维化标志蛋白的变化水平,并通过双萤光素酶报告基因检测系统鉴定mi R-29b对TGF-β1的直接靶向结合情况。结果:随着HSC活化加深,mi R-29b的表达量逐渐减少(P 0. 01),而HSC活性标志物I型胶原蛋白和α-平滑肌肌动蛋白的表达量逐渐增加(P 0. 01)。在TGF-β/Smad信号通路中,Smad2/3/4的表达显著增加,而Smad7的表达明显下降(P 0. 01)。双萤光素酶报告基因检测结果显示,mi R-29b可直接结合于TGF-β1 3’UTR的"UCUCUCCGU"序列,表明TGF-β1为mi R-29b的一个下游靶基因。结论:mi R-29b可参与抑制HSC的活化和迁移,进而抑制肝纤维化进程,而其生物学功能可能是通过直接靶向抑制TGF-β1进而调控TGF-β/Smad信号通路实现的。 相似文献
160.
Ono S Kushiro K Zakir M Meng H Sato H Uchino Y 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,134(1):1-8
Properties of otolith inputs to vestibulocerebellar neurons were investigated in 14 adult cats. In the vestibular nuclei, we recorded single-unit activities that responded orthodromically after stimulation of the utricular and/or saccular nerves and antidromically after stimulation of the cerebellum (uvula-nodulus and anterior vermis). Descending axonal projections to the spinal cord were also examined by antidromic stimulation of the caudal end of the C1 segment. Forty-seven otolith-activated neurons that projected to the uvula-nodulus were recorded. Thirteen (28%) of the 47 neurons received convergent inputs from the utriculus and sacculus. The remaining 34 (72%) vestibular neurons were non-convergent neurons: 18 (38%) received utricular input alone, and 16 (34%) received saccular input alone. Most (35/47) vestibulocerebellar neurons were located in the descending vestibular nucleus and only one of these projected to the spinal cord. Seven of the 47 vestibulocerebellar neurons were located in the lateral vestibular nucleus and most of these neurons projected to the spinal cord. The remaining neurons were located in group X (two neurons) and the superior vestibular nucleus (three neurons). In a different series of experiments, 37 otolith-activated vestibular neurons were tested to determine whether they projected to the uvula-nodulus and/or the anterior vermis. Nineteen of the 37 neurons projected to the anterior vermis, 13/37 projected to the uvula-nodulus, and 5/37 projected to both. The utricular and/or saccular nerve-activated vestibulocerebellar neurons projected to not only the uvulanodulus, but also to the anterior vermis. In summary, the results of this study showed that vestibular neurons receiving inputs from the utriculus and/or sacculus projected to the cerebellar cortex. This indirect otolith-cerebellar pathway terminated both in the anterior lobe and in the uvula/nodulus. 相似文献