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BACKGROUND: Bacterial vaginosis (BV) is associated with complications of pregnancy and increased susceptibility to human immunodeficiency virus (HIV) sexual transmission. METHODS: The ability of genital mucosal fluids from women with BV and of microbial flora associated with BV to induce tumor necrosis factor (TNF)- alpha secretion and Toll-like receptor (TLR) 2 and TLR4 mRNA expression was assessed. RESULTS: Primary peripheral-blood mononuclear cells and THP-1 monocytic cells secreted TNF- alpha in response to cervicovaginal lavage (CVL) samples from women with BV. Mycoplasma hominis and Gardnerella vaginalis also stimulated TNF- alpha secretion. Strikingly, CVL samples from women with BV induced up to 60-fold increases in TLR4 mRNA expression, compared with CVL samples from women without BV and with bacteria not associated with BV. Anti-TNF- alpha antibody blocked increases in TLR4 mRNA expression induced by CVL samples from women with BV, indicating that TNF- alpha plays a critical role in induction of TLR4. Both TLR2 and TLR4 mRNA expression were approximately 60-fold higher in cells isolated from the lumen of the genital tract than in cervical mucosal tissue, but lumen TLR mRNA levels did not change significantly after BV treatment. CONCLUSIONS: These experiments show that genital mucosal fluids and certain bacteria from women with BV stimulate TNF- alpha secretion and TLR4 mRNA expression, suggesting mechanisms whereby BV affects pregnancy and HIV transmission.  相似文献   
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Gascon  P; Zoumbos  NC; Scala  G; Djeu  JY; Moore  JG; Young  NS 《Blood》1985,65(2):407-413
Anti-thymocyte globulin (ATG) provides effective therapy for many patients with aplastic anemia, and its mechanism of action has been presumed to be secondary to lymphocytotoxicity. However, our studies of lymphocyte function in aplastic anemia show marked abnormalities of lymphokine production, which ATG may modulate. In 12 of 17 patients with aplastic anemia, interleukin 2 (IL2) production was markedly elevated in vitro (P less than .01 by paired statistical analysis). Expression of the IL2 receptor, or Tac antigen, on peripheral lymphocytes assessed by flow microfluorometry was also increased above the normal range in 11 of 15 cases. Studies of ATG suggested that it might act to stimulate lymphocyte function. In vitro, ATG is a mitogen, as measured by incorporation of 3H-thymidine into blood mononuclear cells; the response of cells to ATG from patients with aplastic anemia was exaggerated in comparison with normals. Cell proliferation was accompanied by production of IL2 to levels that were, in some cases, similar to those obtained with lectin stimulation. Finally, supernatants from lymphocytes cultured in the presence of ATG were able to replace adherent cells in providing growth factors for the support of nonadherent cells in methylcellulose hematopoietic colony assays. These results provide a mechanism for an "immunostimulatory" action of ATG in effecting hematopoietic response in some patients with aplastic anemia.  相似文献   
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目的:观察正常人近端肾小管上皮细胞(HK2)是否表达黏附分子CD146,初步探讨CD146与肾小管上皮细胞的关系及其生理意义。方法:实验于2005-05/2006-02在上海交通大学医学院临床检验系实验室完成。①实验材料:人近端肾小管上皮细胞株(HK2,由中国科学院上海生物化学与细胞生物学研究所惠赠)。②实验干预:体外培养的HK2连续观察72h。③实验评估:采用倒置显微镜、光学显微镜下观察肾小管上皮细胞的形态;用反转录-聚合酶链反应方法检测CD146 mRNA的表达;流式细胞仪和免疫荧光法测定CD146蛋白质的表达及其定位;进一步在培养细胞的上清液中检测CD146的可溶性形式(sCD146)。结果:①肾小管上皮细胞的形态学观察和鉴定:传代培养的HK2三四天融合后呈铺路石样铺于培养瓶底,相关抗原检测抗人keratin阳性,抗Ⅷ因子相关抗原阴性。②CD146 mRNA水平的表达:HK2在培养早期(24h)即表达CD146 mRNA(0.092±0.012),但延长细胞的培养时间似乎并没有进一步改变CD146 mRNA的表达水平(0.097±0.005,0.113±0.015,P>0.05)。③CD146蛋白质水平的表达和定位:CD146不仅位于肾小管上皮细胞膜上,而且在细胞核和胞浆中也有表达。体外培养的HK2相互融合时,位于细胞膜上的CD146表达增强,呈线性、持续性地表达于细胞-细胞间的连接部位,同时胞内的CD146标记也相应增强。④细胞上清液中sCD146的检测:HK2上清液中存在CD146的可溶性形式(sCD146)。培养细胞观察24~72h,sCD146水平在48h升高[(18.00±0.80)μg/L],到72h达到高峰[(29.33±1.22)μg/L],与24h[(13.87±0.46)μg/L]比较,差异均有显著性意义(P<0.05)。结论:人近端肾小管上皮细胞组成性地表达CD146,是肾小管上皮细胞新的生物学标志;CD146在细胞内外的表达强度有赖于细胞间联系的建立和细胞增殖的程度,CD146在促进细胞生长和维持组织完整性等方面发挥重要作用。肾小管上皮细胞上清液中存在CD146的可溶性形式,sCD146在一定程度上也反映了细胞的生长和增殖状况。  相似文献   
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BACKGROUND: Slow flow or no reflow phenomenon is increasingly being recognized as a serious problem during coronary angioplasty and stenting. This phenomenon is seen more often during angioplasty in highly thrombogenic milieux, especially in a setting of acute myocardial infarction. The treatment of this complication is often not satisfactory. efficacy of abciximab, a potent antiplatelet drug, in treating slow flow or no reflow phenomenon during primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction (AMI). METHODS: Twenty-one instances of persistent slow flow phenomenon were encountered in 131 consecutive patients subjected to primary PTCA for AMI (16%). It was more common in patients presenting with AMI complicated by cardiogenic shock (nine of 21, 43%). Of these 21 cases of slow flow, 10 patients were given injection abciximab during the procedure of primary PTCA as a bail-out measure after encountering the complication of slow flow or no reflow. A predischarge coronary angiography was carried out in all patients who survived. RESULTS: In seven of 10 patients in the abciximab group flow had improved to TIMI-3. In contrast, in the non-abciximab group TIMI flow improved in only four of 11 patients. Patients with persistent slow In this study the authors assessed the flow had significantly higher mortality at the first 30-day follow-up than patients with TIMI-3 flow (33% versus 1.8%, p<0.001). CONCLUSION: In this small nonrandomized study significant improvement in coronary flow was achieved by using intravenous abciximab after observing slow flow or no reflow phenomenon during primary PTCA. More frequent use of this drug in this milieu might help in preventing the development of this complication. Larger studies are warranted to confirm this life-saving beneficial effect of bail-out administration of abciximab during primary angioplasty. (Int J Cardiovasc Intervent 2000; 3:35–39)  相似文献   
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We have previously reported that Morinda citrifolia (noni) puree modulates neonatal calves developmental maturation of the innate and adaptive immune system. In this study, the effect of noni puree on respiratory and gastrointestinal (GI), health in preweaned dairy calves on a farm with endemic salmonellosis was examined. Two clinical trials were conducted whereby each trial evaluated one processing technique of noni puree. Trials 1 and 2 tested noni versions A and B, respectively. Puree analysis and trial methods were identical to each other, with the calf as the experimental unit. Calves were designated to 1 of 3 treatment groups in each trial and received either: 0, 15 or 30 mL every 12 hr of noni supplement for the first 3 weeks of life. Health scores, weaning age, weight gain from admission to weaning, and weaned by 6 weeks, were used as clinical endpoints for statistical analysis. In trial 1, calves supplemented with 15 mL noni puree of version A every 12 hr had a higher probability of being weaned by 6 weeks of age than control calves (P = 0.04). In trial 2, calves receiving 30 mL of version B every 12 hr had a 54.5% reduction in total medical treatments by 42 days of age when compared to controls (P = 0.02). There was a trend in reduced respiratory (61%), and GI (52%) medical treatments per calf when compared to controls (P = 0.06 and 0.08, respectively). There were no differences in weight gain or mortality for any treatment group in either trial.  相似文献   
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