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51.
52.
Manuel Modolell Ines M. Corraliza Franz Link Germn Soler Klaus Eichmann 《European journal of immunology》1995,25(4):1101-1104
Activation with lipopolysaccharide induces macrophages to produce the enzymes arginase and nitric oxide (NO) synthase. Both enzymes use as a substrate the amino acid L-arginine, which can be either hydrolyzed by arginase to urea and ornithine or oxidized by NO synthase to NO and citrulline. NO is important in the bactericidal and cytotoxic activities of macrophages. An equivalent functional role of arginase and its products is not known. We tested the induction of arginase in bone marrow-derived macrophages by endogenous mediators that are known to induce NO synthase, such as interferon-γ (IFN-γ), or suppress the induction of this enzyme, such as interleukin (IL)-4, IL-10, and prostaglandin E2 (PGE2). We find that PGE2 and the TH2 cytokines IL-4 and IL-10 are potent inducers of arginase. In contrast, the TH 1 cytokine IFN-γ does not induce arginase. Simultaneous application of both types of mediators leads to reduced induction of both arginase and NO synthase. Exposure of macrophage cultures to inducers of NO synthase exhausts their ability to respond subsequently to inducers of arginase. Conversely, exposure of the cells to inducers of arginase exhausts their ability to respond subsequently to inducers of NO synthase. The results are consistent with a competition of both enzymes for their substrate, L-arginine, with a reciprocal inhibition in the induction of both enzymes, or a combination of both phenomena. The enzymes NO synthase and arginase appear to define two alternate functional states of macrophages, induced by TH 1 and TH 2 cytokines, respectively. 相似文献
53.
Hypereosinophilic syndrome in Hodgkin's disease with increased granulocyte-macrophage colony-stimulating factor 总被引:2,自引:0,他引:2
We report a patient with eosinophilia accompanied by Hodgkin's disease who showed remarkable increase in granulocyte-macrophage colony-stimulating factor (GM-CSF) in plasma but no increase in interleukin-5 (IL-5). The plasma GM-CSF level normalized as eosinophilia and lymphadenopathy disappeared after chemotherapy. Immunohistochemical study with immunoperoxidase staining technique showed a positive stain in lymph node cells by monoclonal anti-GM-CSF antibody. Eosinophilia is often accompanied by Hodgkin's disease, and several cases have been reported to show high levels of plasma IL-5. To our knowledge, this is the first report to show a high level of plasma GM-CSF in Hodgkin's disease with eosinophilia. 相似文献
54.
应用APAAP法对15例肺癌TIL部分膜抗原的表达动态进行了免疫组化分析。结果显示:未经激活的TIL细胞,其膜抗原(CD~+3,CD~+4,CD~+8)的表达动态基本恒定,经IL-2激活的TIL细胞体外培养一段时期后,其CD~+3细胞数明显上升,同时CD~+8的表达逐渐减少,而CD~+4的表达在培养后期明显增多。 相似文献
55.
Detection of cytoplasmic IL-1 beta in peripheral blood mononuclear cells from intensive care unit (ICU) patients. 总被引:1,自引:0,他引:1 下载免费PDF全文
Cytokines including IL-1 beta have been implicated in the pathophysiology of sepsis and the systemic inflammatory response. It is believed that certain critically ill patients may be 'primed' with respect to cytokine production, and that subsequent 'triggers' may cause exaggerated cytokine production in these patients with exacerbation of their clinical condition; however, no means of identifying 'primed' patients has been described. The presence of cytoplasmic IL-1 beta within peripheral blood mononuclear cells (PBMC) from patients in the ICU was investigated as a means of identifying 'primed' patients, using fluorescent antibody labelling and flow cytometry. The study revealed that PBMC from ICU patients had a different staining pattern for IL-1 beta than those from healthy subjects, and that PBMC from certain ICU patients did indeed stain strongly for IL-1 beta; however, the presence of these strongly staining cells was not associated with clinical condition or outcome. It is concluded that whilst it might be possible to identify 'primed' patients in the ICU using this technique, this is of no clinical value as a predictor of clinical course. 相似文献
56.
Jack C. Kim 《Archives of pharmacal research》1994,17(3):204-206
A regioselective preparation of 10-methoxy-11-hydroxyaporphine (“Apocodeine,1b”) from (R,S)-10, 11-dihydroxyaporphine(apomorphine,1a) is described. The isopropylidene ketal ring of 10,11-(isopropylidenyldioxy) aporphine (2) obtained by the isopropylidenation of apomorphine, was regioselectively opened by the ten equivalent of trimethylaluminum
to give 10-hydroxy-11-t-butyloxyaporphine (3). The free 10-hydroxyl position of 3 was methylated with methyl p-toluenesulfonate/NaH, and afforded 10-methoxy-11-t-butyloxyaporphine
(4) in high yield. Selective debutylation gave the desired 10-methoxy-11-hydroxyaporphine (“apocodeine”,1b) in good yield. 相似文献
57.
高效液相色谱法测定辅酶Q_(10)含量的研究 总被引:9,自引:0,他引:9
应用色谱技术,建立了辅酶Q_10(CoQ_10)含量测定的高效液相色谱方法.并从多个影响保留时间的因素中选出三个水平、三个因子进行正交设计,从而确定了CoQ10。含量测定的最佳条件。本法选用碳十八硅烷为固定相,检测波长为275um,经过多批COQ10。测定,其回收率大于99.6%,RSD小于0.07%,方法简便快速、灵敏度高、特异性强,适用于该药品的含量分析检测。 相似文献
58.
J. B. Payne R. A. Reinhardt M. P. Masada L. M. DuBois A. C. Allison 《Journal of periodontal research》1993,28(6):451-453
Gingival crevicular fluid (GCF) IL-8 and IL-1,1β levels were determined by sandwich enzyme-linked immunosorbent assays. Associations between IL-8 and IL-1β GCF levels, and between these cytokines and patient estrogen status were evaluated. IL-8 and IL-1β were detected more frequently and in higher amounts/30 s GCF sample in estrogen-deficient patients than in estrogensufficient patients. IL-8 and IL-1β GCF levels were significantly correlated. These lindings suggest that GCF IL-8 levels are associated with patient estrogen status and local IL-1β concentrations. 相似文献
59.
目的研究IFN-γ,IL-4水平对血透患者外周血淋巴细胞(PBLC)凋亡调控蛋白Fas,Bcl-2表达的影响.方法采用流式细胞术的间接免疫荧光素标记法和双抗体夹心ELISA法,分别检测30例HD患者PBLC Fas,Bcl-2的表达水平和血清IFN-γ,IL-4水平.结果H-D患者血清IFN-γ水平明显低于健康对照组,IL-4浓度显著高于对照组(P均<0.01);其外周血PBLC的Fas表达水平明显高于健康对照组,而Bcl-2水平则明显低于健康对照组(P均<0.01).经相关分析发现:Fas表达水平与血清IFN-γ水平呈负相关,而与血清IL-4水平呈正相关(P均<0.01);Bcl-2表达水平与血清IFN-γ水平呈正相关,而与血清IL-4水平呈负相关(P均<0.01).结论HD患者PBLC存在异常凋亡现象;并与Th1型细胞因子分泌低下,以及TTh2型细胞因子分泌增加之间有一定的相关性,上述改变可能在HD患者的免疫功能紊乱中起着重要作用. 相似文献
60.
Effects of mycophenolic acid on IL-6 expression of human renal proximal and distal tubular cells in vitro. 总被引:1,自引:0,他引:1
BACKGROUND: Interleukin-6 (IL-6) is a multifunctional cytokine which regulates immune responses and host defence mechanisms. IL-6 has been found to be increased in certain inflammatory conditions of the kidney, in which tubular epithelial cells play a pivotal role. Human renal tubular cells express IL-6. Until now no data about the effect of the immunosuppressant drug mycophenolic acid (MPA) on IL-6 expression were available. METHODS: Proximal and distal tubular epithelial cells (PTC/DTC) have been isolated immunomagnetically. Confluent monolayers were stimulated with interleukin-1beta (IL-1beta; 25 U/ml), IL-1beta+ MPA (0.25-50 micro M) or MPA alone for 48 h. Release of IL-6 protein into the supernatant was evaluated with an enzyme immunoassay, IL-6 mRNA expression was evaluated using the Quantikine mRNA kit. RESULTS: After IL-1beta stimulation, a highly significant 2.6- (PTC) and 3.8-fold (DTC) upregulation of IL-6 expression was detectable. IL-6 mRNA was upregulated by IL-1beta [1.57- (PTC) and 2.03-fold (DTC)]. MPA inhibited this cytokine-induced IL-6 expression in a dose-dependent manner. Incubation with the lowest MPA concentration had no effect on the stimulated upregulation, whereas all higher doses significantly decreased IL-6 expression. Dexamethasone significantly inhibited the cytokine-induced IL-6 protein release in PTC, but not in DTC. CONCLUSIONS: In this study we demonstrated for the first time an inhibitory effect of MPA on the stimulated IL-6 expression of renal tubular epithelial cells. In contrast to older data, which showed a synergistic upregulation of the expression of a CC-chemokine by a combination of cytokines and MPA, in the present study we could demonstrate an immunosuppressive effect of MPA on the expression of an important cytokine. 相似文献