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101.
目的:探讨IL-6对人精子顶体反应(AR)的影响机制。方法:采用BAEE/ADH法测定精子顶体酶的活性,以及通过FITC-PSA法检测精子顶体反应。结果:IL-6可诱导精子顶体酶及超氧化物歧化酶(SOD)的活性,促进精子顶体反应;胞外Ca2+单独不能诱导精子顶体反应,且没有胞外Ca2+的参与,IL-6也不能诱导精子顶体反应;蛋白激酶C(PKC)抑制剂calphC能逆转IL-6诱导的精子顶体反应。结论:IL-6对精子顶体反应有一定的促进作用,可能通过诱导精子的顶体酶和SOD活性等途径来实现,在此作用中,也涉及了PKC的激活,且还需要外源性Ca2+的参与。 相似文献
102.
Abstract In inflammatory dermatoses. activated T cells produce inter-feron-gamma (IFN-γ), which interacts with keratinocytes and contributes to the direct activation of these cells by inducing, among other factors, the expression of HLA-DR antigens and intercellular adhesion molecule-1. However, the action of IFN-γ on epidermal cell cytokine production is not known. Our aim was to assess the effect of IFN-γ on the production of IL-1 by normal human keratinocytes cultured in low calcium medium (MCDB153). In comparison with controls, the addition of nontoxic IFN-yγ concentrations (50-500 U/ml) to cell cultures induced a significant increase of IL-1α and IL-1β production predominantly after 100 U/ml treatment in the cell extracts as well as in the supernatants at 24h and 48h. The production of the antagonist. IL-1RA, was also enhanced and the effect of the critical concentration (100 U/ml) was more evident. However, the absence of a characteristic dose response could not be explained by an antiproliferative effect of high IFN-γ concentrations (250 and 500 U/ml) on cultured keratinocytes or by the induction of the nuclear stress protein, Hsp72. two phenomena known to down-regulate IL-1 biosynthesis. In conclusion, the modifications in keratinocyte IL-1 production under IFN-γ stimulation can contribute to activate the epidermal cells and thus involve them in the local immune response. 相似文献
103.
Tatsuya Okimoto Hiroshi Yahata Yasuhiko Fukuda Keisuke Hayamizu Kiyohiko Dohi 《Transplant international》1994,7(S1):629-633
Abstract A study was conducted to elucidate the mechanism of donor-pecific Mixed Lymphocyte Reaction (MLR and Cell Mediated Lymphotoxicity (CML) unresponsiveness in a renal transplant recipient with a long-term well-functioning kidney. The peripheral blood lymphocytes (PBL) of the recipient, who had not shown rejection since his transplantation 5 years previously, and those of his mother (donor), his father and two healthy third parties were examined. MLR, CML, semimicro MLR in a double chamber, interleukin-2 (IL-2) synthesis assay and limiting dilution assay were performed. This recipient showed donor-pecific MLR and CML unresponsiveness. IL-2 assay showed that the PBL of the recipient produced less IL-2 against the donor than against the father and the third parties. The addition of exogenous recombinant IL-2 (rIL-2; Takeda Co.) to the priming MLR caused a recovery of CML against the donor. A limiting dilution assay indicated that cytotoxic T cell precursor (CTLp) frequencies against the donor and father did not differ. The suppressor assay in a double chamber indicated that the PBL of the recipient stimulated by the donor PBL had a non-pecific suppressive effect on MLR, CML and IL-2 synthesis of the PBL across the Major Histocompatibility Complex (MHC) barrier. This suppressive effect was abolished by OKT3 or OKT8 monoclonal antibody and complement. Thus, the recipient had donor-pecific suppressor T cells that produced a humoral non-pecific suppressive factor only when stimulated by the donor PBL, and this factor suppressed PLR and CML by inhibiting IL-2 synthesis of the PBL. 相似文献
104.
R. D. Myers F. J. Lopez-Valpuesta F. J. Minano M. H. Wooten V. S. Barwick S. D. Wolpe 《Journal of neuroscience research》1994,39(1):31-37
The chemokines, macrophage inflammatory protein-1 (MIP-1) and its subunit MIP-1β, induce an intense fever in the rat when they are injected directly into the anterior hypothalamic, pre-optic area (AH/POA), a region containing thermosensitive neurons. The purpose of this study was to compare the central action on body temperature (Tb) of MIP-1β with that of interleukin-6 (IL-6), which also has been implicated in the cerebral mechanism underlying the pathogenesis of fever. Following the stereotaxic implantation in the AH/POA of guide cannulae for repeated micro-injections, radio transmitters which monitor Tb continuously were inserted intraperitoneally in each of 15 male Sprague-Dawley rats. Each micro-injection was made in a site in the AH/POA in a volume of 1.0 μl of pyrogen-free artificial CSF, recombinant murine MIP-1β, or recombinant human IL-6. MIP-1β in a dose of 25 pg evoked an intense fever characterized by a short latency, a mean maximum rise in Tb of 2.4 ± 0.21°C reached by 3.7 ± 0.42 hr, and a duration exceeding 6.5 hr. Injected into homologous sites in the AH/POA, IL-6 induced a dose dependent fever of similar latency and a mean maximal increase in Tb of 1.2 ± 0.25°C, 1.8 ± 0.15°C, and 2.1 ± 0.22°C and duration of 6.2 ± 1.28 hr, 6.7 ± 0.49 hr, and 6.8 ± 0.65 hr when given in doses of 25, 50, and 100 ng, respectively. These results show that MIP-1β and the highest dose of IL-6 induce a fever of comparable intensity, but MIP-1β exerts its action in a much lower concentration. Thus, the de novo synthesis and subsequent action of the MIP-1 family of cytokines on neurons of the AH/POA in response to a pyrogen challenge apparently play a functional role in the pathogenesis of fever. Further, the endogenous activity of IL-6 in the hypothalamus which is enhanced in response to a lipopolysaccharide also may reflect its essential part in the acute phase response to a bacterial challenge. Copyright © 1994 Wiley-Liss, Inc. 相似文献
105.
胃癌患者红细胞免疫功能的变化 总被引:4,自引:1,他引:3
运用简单形态学方法测定了30例胃癌患者红细胞免疫功能,结果表明:胃癌患者红细胞C3b受体花环率及肿瘤红细胞花环率显著低于正常对照(P<0.01)及慢性良性胃病患者(P<0.01),而免疫复合物花环率则高于正常人(P<0.01)及慢性良性胃病患者(P<0.01);Ⅲ、Ⅳ期胃癌患者肿瘤红细胞复合物花环率明于低于Ⅰ、Ⅱ期患者(P<0.01);贲门癌肿瘤红细胞花环率显著低于胃窦(体)癌患者(P<0.01) 相似文献
106.
Xuyu Zu Ruilan Yan Sarah Robbins Paulette A Krishack Duan-Fang Liao Deliang Cao 《Toxicological sciences》2007,97(2):562-568
Acrolein is a highly reactive alpha,beta-unsaturated aldehyde produced endogenously during lipid peroxidation and naturally distributed pervasively in living environments, posing serious threats to human health if not properly metabolized. In this study, we report aldose reductase-like-1 (ARL-1) as a novel enzyme that catalyzes the reduction of acrolein and protects cells from their toxicity. Using purified ARL-1 protein, we determined its enzymatic activity in response to acrolein and defined its steady-state kinetics with K(m) and V(max) at 0.110 +/- 0.012 mM and 3122.0 +/- 64.7 nmol/mg protein/min, respectively. By introducing a functional Enhanced Green Fluorescent Protein (EGFP)/ARL-1 fusion protein into 293T cells, we demonstrated that plating efficiency in liquid culture and focus formation in soft agar increased by more than 60% (p < 0.05), compared to the vector control cells. More significantly, at a low dose of 5 microM acrolein, EGFP/ARL-1 expression enhanced both plating efficiency and focus formation by more than threefold, and the foci (in soft agar) of 293T cells expressing EGFP/ARL-1 were significantly larger than those of the vector control cells. At high concentrations of acrolein (25 and 50 microM), EGFP/ARL-1 protein prevented oncotic death of 293T cells induced by acrolein. In summary, our data demonstrated for the first time that the ARL-1 protein protects 293T cells from acrolein toxicity. Due to the high toxicity and wide distribution of acrolein, this finding is important to the understanding of its detoxification mechanisms. 相似文献
107.
108.
目的对临床12种昏厥进行ICD-10编码.方法根据临床12种昏厥的不同病因病理、临床表现,结合ICD-10编码规则对其进行ICD-10编码.结果根据临床分类,昏厥可分为12种及其对应编码.结论对于不能直接从ICD-10(三卷)中找到的昏厥编码,需根据其病因病理、临床表现变换主导词,在ICD-10中找到对应的编码. 相似文献
109.
本文观察16例大肠癌病人的癌组织培养上清液对人T细胞的增殖,ZL—2产生的影响和病理Dukes分期的关系,发现癌组织的TDSF对T细胞的增殖有显著抑制作用,对ZL—2的产生抑制作用不明显,对T细胞增殖率在DukesA与B期,其值与对照有显著差异(0.01P<0.05).在C期有非常显著差异(P<0.01).说明大肠癌组织确实分泌有能造成宿主免疫功能下降的抑制物质.且免疫作用不是通过ZL—2环节发生. 相似文献
110.
P. H. Mogensen L. Jórgensen J. Boas M. Dam A. Vesterager G. Flesch P. K. Jensen 《Acta neurologica Scandinavica》1992,85(1):14-17
The effects of dextropropoxyphene on the steady-state kinetics of oxcarbazepine and its metabolites were investigated in eight patients with epilepsy or trigeminal neuralgia. One patient dropped out of the study, presumably due to side-effects of dextropropoxyphene. Dextropropoxyphene did not affect the plasma levels of the principal active metabolite, 10,11-dihydro-10-hydroxy-carbamazepine. Since dextropropoxyphene is known to increase the plasma levels of carbamazepine, leading to toxicity, the findings of this study suggest that oxcarbazepine is a useful alternative to carbamazepine when concomitant dextropropoxyphene therapy is required. 相似文献