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1.
Ablation of rat myenteric plexus with benzalkonium chloride has provided a model of intestinal aganglionosis, but the degenerative responses are not well understood. We examined the effects of this detergent on neurons and glia, including expression of c-Myc, c-Jun, JunB, and c-Fos, and on immunocytes in the guinea-pig ileum. Benzalkonium chloride (0.1%) or saline was applied to the serosal surface of distal ileum. Tissues were analyzed 2, 3, or 7 days later and compared with cyclosporine-treated and untreated animals. More than 90% of myenteric neurons were destroyed in ileal segments 3–7 days after benzalkonium-chloride treatment. Glia withdrew processes from around neurons after 2 days and were mostly gone after 3 days. Neuronal c-Myc began to disappear while c-Fos, c-Jun, and JunB were evident in some neuronal nuclei after 2 or 3 days. After 3 days, widespread apoptosis was evident in the myenteric plexus. Populations of T cells, B cells, and macrophage-like cells in untreated and saline-treated myenteric plexuses were substantially increased 3 and 7 days after benzalkonium-chloride treatment. Cyclosporine delayed significant neuronal loss. We conclude that a variety of degenerative mechanisms may be active in this model, including an immune response which may actively contribute to tissue destruction. Received: 13 September 1996 / Accepted: 20 January 1997  相似文献   
2.
Herein, we studied phorate for its toxicological effects in human lymphocytes. Phorate treatment for 3 h has induced significant increase in the lymphocytic DNA damage. Compared to control, comet data from highest concentration of phorate (1000 µM) showed 8.03-fold increase in the Olive tail moment (OTM). Cytokinesis blocked micronucleus (CBMN) assay revealed 6.4-fold increase in binucleated micronucleated (BNMN) cells following the exposure with phorate (200 µM) for 24 h. The nuclear division index (NDI) in phorate (200 µM) treated cells reduced to 1.8 vis-à-vis control cells showed NDI of 1.94. Comparative to untreated control, 60.43% greater DCF fluorescence was quantitated in lymphocytes treated with phorate (500 µM), affirming reactive oxygen species (ROS) generation and oxidative stress. Flow cytometric data of phorate (200 µM) treated lymphocytes showed 81.77% decline in the fluorescence of rhodamine 123 (Rh123) dye, confirming the perturbation of mitochondrial membrane potential (ΔΨm). Calf thymus DNA (ct-DNA) treated with phorate (1000 µM) exhibited 2.3-fold higher 8-Hydroxy-2′-deoxyguanosine (8-oxodG) DNA adduct formation, signified the oxidative DNA damage. The alkaline unwinding assay revealed 4.0 and 6.5 ct-DNA strand breaks when treated to phorate and phorate-Cu (II) complex. Overall, the data unequivocally suggests the cyto- and genotoxic potential of phorate in human lymphocytes, which may induce comparable toxicological consequences in persons occupationally or non-occupationally exposed to insecticide phorate.  相似文献   
3.
肉苁蓉多糖的促淋巴细胞增殖作用   总被引:1,自引:0,他引:1  
目的研究肉苁蓉多糖(CDPS)对小鼠淋巴细胞增殖的影响。方法MTT法检测小鼠脾淋巴细胞的增殖。环磷酰胺(Cy)复制免疫功能低下的动物模型,分别测定正常及免疫低下动物脾脏、胸腺指数。胸腺细胞增殖法测定白细胞介素-2(IL-2)活性。结果CDPS对丝裂原(ConA及LPS)活化淋巴细胞及未活化正常细胞均有明显促增殖作用,并促进淋巴细胞IL-2的分泌。腹腔给药显示CDPS具明显提高正常及免疫低下小鼠的脾指数,对因Cy所致胸腺指数的降低也有显著的对抗作用。结论CDPS可显著促进小鼠脾淋巴细胞增殖,该作用可能与其促IL-2分泌有关。  相似文献   
4.
Despite early reperfusion, patients with ST segment elevation myocardial infarction (STEMI) may present large myocardial necrosis and significant impairment of ventricular function. The present study aimed to evaluate the role of subtypes of B lymphocytes and related cytokines in the infarcted mass and left ventricular ejection fraction obtained by cardiac magnetic resonance imaging performed after 30 days of STEMI. This prospective study included 120 subjects with STEMI submitted to pharmacoinvasive strategy. Blood samples were collected in subjects in the first (D1) and 30th (D30) days post STEMI. The amount of CD11b+ B1 lymphocytes (cells/ml) at D1 were related to the infarcted mass (rho = 0.43; P=0.033), measured by cardiac MRI at D30. These B1 cells were associated with CD4+ T lymphocytes at D1 and D30, while B2 classic lymphocytes at day 30 were related to left ventricular ejection fraction (LVEF). Higher titers of circulating IL-4 and IL-10 were observed at D30 versus D1 (P=0.013 and P<0.001, respectively). Titers of IL-6 at D1 were associated with infarcted mass (rho = 0.41, P<0.001) and inversely related to LVEF (rho = −0.38, P<0.001). After multiple linear regression analysis, high-sensitivity troponin T and IL-6 collected at day 1 were independent predictors of infarcted mass and, at day 30, only HDL-C. Regarding LVEF, high-sensitivity troponin T and high-sensitivity C-reactive protein were independent predictors at day 1, and B2 classic lymphocytes, at day 30. In subjects with STEMI, despite early reperfusion, the amount of infarcted mass and ventricular performance were related to inflammatory responses triggered by circulating B lymphocytes.  相似文献   
5.
6.
牙鲆淋巴细胞转化和细胞免疫   总被引:3,自引:1,他引:2  
利用淋巴转化实验测试了抗原和有丝分裂原对牙鲆T淋巴细胞的影响。结果显示在适宜的生长温度范围内,低温延缓或阻止牙鲆细胞免疫应答的发生,导致淋转水平下降。外周血和脾淋巴细胞非特异性淋转水平较前肾高,外周血和脾淋巴细胞的淋转水平没有显著差异。这可能和外周血、脾和前肾中T细胞占淋巴细胞的比例有关。外周血较脾和前肾特异性淋转水平高,而前肾的淋巴细胞转化水平较脾高,注射引起牙鲆应激反应导致淋转水平升高。  相似文献   
7.
The present work is aimed at evaluating the radioprotective effect of curcumin, a naturally occurring phenolic compound on γ-radiation induced toxicity. The cellular changes were estimated by using lipid peroxidative indices like thiobarbituric acid reactive substances (TBARS), the antioxidants superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and reduced glutathione (GSH). The DNA damage was analysed by using cytokinesis blocked micronucleus assay and dicentric aberration (DC). The γ-radiation at different doses (1, 2 and 4 Gy) were found to significantly increase micronuclei (MN), DC frequencies and TBARS level whereas the levels of GSH and antioxidant enzymes were significantly decreased. The maximum damage to lymphocytes was observed at 4 Gy irradiation. Curcumin pretreatment (1, 5 and 10 μg/ml) significantly decreased the frequency of MN and DC. The levels of TBARS decreased and activities of SOD, CAT and GPx significantly increased along with GSH levels. At 1 Gy irradiation all the concentrations of curcumin (1, 5 and 10 μg/ml) significantly protected the lymphocytes from radiation damage. At 2 Gy irradiation, 5 and 10 μg/ml of curcumin showed significant radioprotection. Since the highest damage was observed at 4 Gy irradiation both 1 and 5 μg/ml of curcumin pretreatment were not sufficient to protect the lymphocytes from radiation damage but 10 μg/ml of curcumin significantly protected the cultured lymphocytes from radiation damage. Thus, pretreatment with curcumin gives protection to lymphocytes against γ-radiation induced cellular damage.  相似文献   
8.
刘鹏  钱冬萌  王桐梅  宋旭霞  王斌 《生物磁学》2013,(25):4921-4924
目的:肾移植患者由于术前透析及术后服用免疫抑制剂,显著增加了人巨细胞病毒(Humancytomegalovirus,HCMV)原发感染和潜伏感染被激活的机会。观察HCMV感染情况与血T淋巴细胞亚群及肾功能的变化,以探讨其相关性及临床意义。方法:跟踪收集40例肾移植患者术前、术后血标本,应用RT-PCR技术检测HCMV,流式细胞术检测淋巴细胞亚群,结合肾功能判断是否发生急性排斥或移植肾功能恢复延迟。结果:肾移植术后HCMV感染率为52.5%,10例出现症状性感染(25%),出现阳性时间35.7±15.3天。症状性感染组CD3-bCD4+的水平和CD4+/CD8+的比值较无活动性感染组和正常对照组均降低,CD8+水平较其他组升高,差异有显著性意义(P〈0.05)。无症状性活动感染者与无活动性感染者各指标比较差异无显著性。活动性感染组急性排斥或移植肾功能恢复延迟发生8例(38.1%),无活动性感染组发生1例(5.2%),差异具有统计学意义(x^2=6.15,P〈0.05)。结论:肾移植术后HCMV感染能显著引起T淋巴细胞亚群变化,尤其是CD4+/CD8+。并与急性排斥或移植肾功能恢复延迟密切相关联,在其发生发展中可能起着重要的作用。三者相互联系、相互作用、互为因果,对进一步机制的研究及临床诊断治疗、预后方面有一定意义。  相似文献   
9.
Zusammenfassung Die Lymphozyten des Ductus thoracicus von unbehandelten weißen Ratten und von Ratten nach Sensibilisierung mit Meerrettichperoxydase wurden nach einer zweistündigen Vorfixierung in 2,5% Glutaraldehyd in dem Osmium-Zink-Jodid-Gemisch nach Maillet (1959) inkubiert und elektronemikroskopisch untersucht. Es zeigte sich, daß bei den unbehandelten Tieren nur wenige Lymphozyten keine Reaktion im Kernspalt aufwiesen — ER und Golgi waren nicht ausgebildet —, während die Mehrzahl der Zellen eine starke OZI-Imprägnation des Kernspalts, des ER, des Golgifeldes und der Mitochondrienmatrix zeigte. Die Membransysteme und Mitochondrien der Plasmazellen, die in der Ductuslymphe nach Sensibilisierung auftraten, waren ebenfalls stark OZI-positiv. Auf Grund dieser Befunde halten wires für sehr wahrscheinlich, daß das OZI-Gemisch mit bestimmten Proteinen reagiert, auch mit Antikörpern. Bei einer Erhöhung des pH-Werte auf 6,5 findet in den genannten Systemen keine Reaktion mehr statt.
Electron microscopic studies of ductus thoracicus cells of the rat after osmium-zinc-jodide (OZI) impregnation
Summary Ductus thoracicus lymphocytes from untreated white rats and from rats after sensibilisation with horseradish peroxydase were incubated in Maillet's (1959) osmiumzinc-jodide mixture after prefixation in 2.5% glutaraldehyd, and examined electron microscopically. It is demonstrated that among the untreated lymphocytes only few cells show no reaction product in the perinuclear space—ER and Golgi A. are not to be observed—while the majority exhibits strong reaction in the nuclear envelope, the ER, the Golgi field and the matrix of the mitochondria. All plasma cells, present in the thoracic duct lymph after sensibilisation with horseradish peroxidase show also a strong OZI-reaction in their cisternal elements and in the mitochondria. According to these findings there is strong evidence that the OZI-solution reacts with certain proteins also with antibodies. Setting the pH of the OZI-solution to 6.5 no more reaction is found in the formentioned systems.
  相似文献   
10.
单核细胞促进人外周血淋巴细胞离体增殖的自由基机理   总被引:1,自引:0,他引:1  
在人外周血淋巴细胞培养体系中加入不同数量的单核细胞共同培养,以~3H-TdR掺入法和细胞色素C还原法分别测定淋巴细胞增殖能力和培养介质中O_2~-浓度;加入NADPH氧化酶抑制剂DPI实验性地下调O_2~-浓度,观察淋巴细胞增殖能力的变化。结果显示加入单核细胞可增加培养介质中O_2~-浓度,进而促进淋巴细胞增殖,提示O_2~-浓度的升高是淋巴细胞和单核细胞共培养体系中淋巴细胞增殖的重要因素。  相似文献   
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