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11.
旁路活化补体降低PMN吞杀绿脓杆菌力的实验研究 总被引:1,自引:0,他引:1
为证明论题,本文做了3项实验:(1)人血PMN培养单层加上酵母多糖活化人血清(ZAHS)。PMN的超氧离子(O_2~-)、特殊颗粒(SG)与胞内杀菌力(ICBA)明显平行下降,于6 h最低,0.05 ml的作用最强。(2)经小鼠尾静脉注射0.5ml ZAHS/鼠,6 h后活杀。肺和血内PMN的上述指标均明显降低;肺内病变明显:急性间质炎,灶性水肿出血和萎陷,肺血屏障亚微结构损伤。(3)经抗人C_3、C_5血清(AHC_(3.5)S)体外中和的ZAHS,在体内外实验中均失去其有害作用。提示:ZAHS的有害作用与C_3、C_5碎片有关,在剂量适中且吞菌前作用时间较长的条件下方显极效。有害作用的可能机制:杀菌且能致炎的O_2~-与SG大多已于吞菌前排放在胞外,所以PMN的ICBA下降;累积于组织内的则损害PMN自身及其邻近的肺血屏障。这便于MOF与感染发生。 相似文献
12.
以辣根过氧化物酶(PO)和抗-PO作为免疫沉淀中的抗原和抗体,用光电比色法,对78例小儿肾脏疾病血清补体对免疫沉淀的抑制作用(IIPC)进行了研究,并同时检测补体成分C3、C4。结果,正常对照IIPCOD值为0.505±0.085,急性肾小球肾炎(0.137±0.108)显著降低(P<0.001);慢性肾小球肾炎(0.470±0.053)改变不明显(P>0.05);肾病综合征(0.401±0.038)明显低下(P<0.05)。IIPC低下的发生率依次为急性肾小球肾炎(83%)、肾病综合征(43%)、慢性肾小球肾炎(32%)。表明小儿肾小球疾病时IIPC大多降低并与疾病的活动性有关。因此认为IIPC低下在肾脏病的发生和发展中起一定作用。 相似文献
13.
对病理学确诊的25例病毒性心肌炎(VMC)和10例扩张型心肌病(DCM)患者心内膜心肌活检标本,运用ABC技术,进行了免疫球蛋白IgG、IgM、IgA和补体C3的检测。结果:20例VMC和9例DCM的标本中,发现了IgG和IgM的沉积,主要分布于心肌肌膜和毛细血管内皮,IgG的肌膜沉积与同步做的病理切片中观察到的心肌细胞坏死和炎性细胞浸润有病理形态学联系。两组患者中均未发现IgA和C3沉积。结果显示,IgG是参与VMC和DCM心肌损伤的主要免疫球蛋白,心肌病变与抗体诱导的免疫反应有关。 相似文献
14.
Thrombin Inhibition in discordant xenograft rejection 总被引:1,自引:0,他引:1
Beth-Ann Lesnikoski Daniel Candinas Ichiro Otsu Rainer Metternich Fritz H. Bach Simon C. Robson 《Xenotransplantation》1997,4(3):140-146
Abstract: Microvascular thrombosis and the associated platelet and endothelial cell activation are prominent observations in xenograft rejection. This pathological picture could be related to the excessive generation of thrombin in the context of either inflammation or putative inter-species molecular incompatibilities between activated coagulation factors and their natural anticoagulants. Relatively selective thrombin Inhibition with the serine protease inhibitor SDZ MTH 958 (MTH-958) are independent of heparinoids and anti-thrombin III. MTH-958 has been shown to significantly prolong porcine cardiac function during perfusion with human blood in an ex vivo model. The aim of this study was to validate the role of thrombin generation in a rodent model of discordant xenograft rejection in vivo. The effect of thrombin inhibition with MTH-958 was tested in both hyperacute rejection (HAR) and delayed xenograft rejection (DXR) after decomplementation with cobra venom factor (CVF) in normal Lewis (Lew) rats and Intrinsic C6 deficiency In PVG (C6-/PVG) recipient rats. Recipient rats received heterotopic guinea pig cardiac xenografts and were treated with titrated doses of MTH-958 until the time of graft rejection. Plasma samples at selected time points were examined to confirm effective thrombin inhibition, and rejected grafts were analyzed by immunohistology. MTH-958 significantly improved graft survival in HAR albeit the extent of prolongation was not marked, but the agent failed to prolong survival In CVF-treated Lew rats. In C6-/PVG rats receiving MTH-958, a significantly reduced graft survival time was observed when compared with C6-/PVG controls. The grafts from MTH-958-treated animals showed dense deposits of C3, IgM, and IgG with fibrin levels similar to controls. The thrombin antagonist tested could prolong xenograft survival during HAR but had no benefit in DXR. The relative non-specificity of the serine protease inhibitor MTH-958 with the potential activation of alternative pathway of complement via the inhibition of factor I could account for the failure to prolong xenograft survival in DXR. The pathogenetic significance of thrombin generation in this situation remains to be determined by the use of more selective and pharmacologically acceptable I anti-thrombin agents. 相似文献
15.
N. Kamolvarin T. Hemachudha B. Ongpipattanakul K. Phanthumchinda T. Sueblinvong 《Acta neurologica Scandinavica》1991,83(6):382-387
Plasma C3c levels were examined in 56 patients with immune (27) and non-immune (29) mediated neurological diseases by crossed immunoelectrophoresis. Plasma samples were collected during the active phase of illness in both groups, usually within 7 days of admission. 11 patients (4 Guillain-Barré Syndrome-GBS, 3 chronic inflammatory demyelinating polyneuropathy-CIDP, 4 myasthenia gravis-MG) had their plasma saved sequentially during the active and the recovery phase. Plasma C3c levels were elevated in the group with immune mediated diseases when compared with those of non-immune mediated diseases. The sensitivity and specificity of C3c as a diagnostic test for immune mediated neurological diseases were 61.4 and 100% respectively with a positive and negative predictive value of 100 and 41%. the C3c levels in plasma correlated well with disease severity in MG and GBS patients. Such a correlation was also evident in all CIDP patients except one that had persistent elevation in the presence of clinical improvement. Results suggest that the plasma C3c level may be useful for differentiating immune from non-immune mediated neurological diseases. Plasma C3c may also be used for monitoring disease severity, particularly in myasthenia gravis. 相似文献
16.
用放免法检测乙型慢性活动性肝炎病人的红细胞c3b受体(KBCCR1).结果:病人RBCCR1明显低于献血员(P<0.05);抗-HBs特异性免疫复合物阳性病人RBCCR1明显低于阴性病人(P<0.01),与红细胞C3b受体花环试验检测结果一致。表明乙型慢性活动性肝炎病人RBCCR1数量减少,活性下降。其原因可能是特异性循环免疫复合物占据了RBCCR1空位,使CR1活性下降。 相似文献
17.
Summary. Divers have worked at 500 m depth in the sea and have reached 700 m in simulated chamber dives. A prerequisite for this has been extensive physiological studies of the body's reactions to pressure and pressure changes. This paper reviews such physiological and pathophysiological studies with emphasis on recent developments. 相似文献
18.
The binding of human complement components C3, C5 and C9 to the surface of the infective larvae of the nematode parasites Toxocara canis and Trichinella spiralis, by the alternative pathway, was examined by direct and indirect immunofluorescence on the intact parasites. This showed that although C3 bound to both nematodes, they differed markedly in the binding of C5 and C9; C5 bound only minimally to T. spiralis, and C9 binding to this parasite was barely detectable. In contrast, both early and late components bound to T. canis to a high density, comparable to, or in excess of, the binding of these components to the infective larvae of the trematode Schistosoma mansoni. The lack of binding of the post-C3 components to T. spiralis did not correlate with enhanced binding of the control protein, Factor H. 相似文献
19.
C4d Deposition and Clearance in Cardiac Transplants Correlates With Alloantibody Levels and Rejection in Rats 总被引:4,自引:3,他引:1
K. Minami K. Murata C.-Y. Lee K. Fox-Talbot B. A. Wasowska M. D. Pescovitz W. M. Baldwin III 《American journal of transplantation》2006,6(5P1):923-932
Antibody-mediated rejection of human cardiac transplants is correlated with C4d deposits and macrophage infiltrates in capillaries of endomyocardial biopsies. We produced an antibody to rat C4d to study C4d deposition and clearance in Lewis rats that were sensitized with a blood transfusion from DA rats 7, 14 or 21 days before cardiac transplantation. Cyclosporin A (CsA) immunosuppression was initiated after transplantation at a dose that inhibited graft rejection, antibody production and C4d deposition in unsensitized recipients. Blood transfusion elicited high levels of circulating IgG alloantibodies, predominantly of the complement-activating IgG2b subclass, that peaked 14 days after transplantation. At this time, macrophages accumulated in capillaries, and C4d deposits were diffuse and intense on arteries, capillaries and veins. Grafts that survived 90 days in sensitized recipients still had deposits of C4d that were associated with increased interstitial fibrosis and vasculopathy in arteries. Clearance of C4d was determined by retransplanting DA cardiac allografts from Lewis recipients back to DA recipients. C4d deposits were decreased to minimal levels within 5 days after retransplantation. Thus, C4d deposition is not limited to the capillaries, but extends throughout the arterial tree, and despite formation of a covalent bond, C4d is cleared within days. 相似文献
20.
The effects of zymosan-activated plasma(ZAP)on lung fluid exchangeand on superoxide anion production by granulocytes were studied in 8 consciousgoats with chronic lung lymph fistula,It was found that after ZAP infusion, thecirculating granulocytes were activated and the release of superoxide anions wasmarkedly enhanced. There was an increase in lung lymph flow and proteinconcentration.It suggests that the superoxide anion released by the stimulatedgranulocytes can play a role in inducing lung injury by the activated complement. 相似文献