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101.
The mechanism of IgA deposition in the kidneys in IgA nephropathy is unknown, Mesangial IgA is of the IgA I subclass, and since no consistent antigenic target for the IgA I has been described, we have investigated the glycosylation of the molecule, as a potential non-immunological abnormality which may contribute to its deposition. IgA 1 is rich in carbohydrate, carrying N-linked moieties in common with IgG, but also O-linked sugars, which are rare in serum proteins, and not expressed by IgG or lgA2, Lectin binding assays were designed to examine the expression of terminal galactose on the N-linked carbohydrate chains of purified serum IgG and IgAI, and the O-linked sugars of IgAI and C1 inhibitor (one of the very few other serum proteins with O-linked glycosylation). No evidence was found for abnormalities of N-linked glycosylation of either isotype in IgA nephropathy compared with matched controls. However, in IgA nephropathy, reduced terminal galactosylation of the hinge region O-linked moieties was demonstrated; this was not seen in C1 inhibitor, which showed normal or increased galactosylation of the O-linked sugars. This abnormality of IgA1 has considerable implications for the pathogenesis of IgA nephropathy, since the O-linked sugars lie in an important functional location within the IgA1 molecule, close to the ligand of Fc receptors. Changes in the carbohydrates in this site may therefore affect interactions with receptors and extracellular proteins, leading to anomalous handling of the IgA1 protein in this condition, including failure of normal clearance mechanisms, and mesangial deposition.  相似文献   
102.
Previously we reported disease-specific interaction between interferon- (IFN-) and interleukin-4 (IL-4) in patients with IgA nephropathy (IgAN), suggesting the existence of unusual T cell behavior in this disease. In the present study, we investigated characteristic synthesis of interferon- (IFN-) and expression of IFN- receptor (IFN-R) in the peripheral blood mononuclear cells (PBMC) from patients with IgAN and other chronic proliferative glomerulonephritis (PGN). Heparinized peripheral blood samples were obtained from 38 patients with chronic mesangial proliferative glomerulonephritis (CGN; including 24 with IgA nephropathy) and 20 healthy controls. PBMC were isolated by gradient centrifugation and fragments were cultured in Iscove's modified Dulbecco's medium (IMDM) supplemented with 10% fetal calf serum (FCS) for 72 hr. IFN- concentrations in supernatants were evaluated by the enzyme-linked immunosorbent assay (ELISA). Other parts of PBMC pellets were reacted with anti-human IFN-R monoclonal antibody and FITC-labeled anti-mouse second antibody for analysis of IFN-R expression on these cells by FACScan. The remaining PBMC were fractionated into CD4+ T cells, CD8+ T cells, B cells, NK, cells and macrophages using the MACS cell sorting system. The isolated cells were evaluated for IFN- or IFN-R mRNA expression by the semiquantitative RT-PCR method.In vitro IFN- synthesis was enhanced in patients with CGN, and NK cells were revealed to be responsible for such enhancement. On the other hand, the expression of IFN-R on macrophages was suppressed in CGN patients. These results suggest that impairment of regulation of the IFN- system might be involved in the development of CGN.  相似文献   
103.
慢性肾病患者细胞因子测定的临床意义   总被引:1,自引:0,他引:1  
目的:探讨了慢性肾病患者血清IL-6、IL-8、IL-10和IL-18水平的变化及意义。方法:分别应用放射免疫分析和酶联法对32例慢性肾病患者进行了血清IL-6、IL-8、IL-10和IL-18测定,并与35名正常健康人作比较。结果:慢性肾病患者血清IL-6、IL-8、IL-10和IL-18水平显著地高于正常人组(P〈0.01),经治疗6个月后与正常人组比较仍有差异(P〈0.05)。结论:检测慢性肾病患者血清IL-6、IL-8、IL-10和IL-18水平的变化对疾病的预后观察具有重要的临床价值。  相似文献   
104.
T-suppressor function and T-helper function in healthy adults, elderly patients with non-immune diseases, and patients with rheumatoid arthritis (RA) and IgA nephropathy (IgAN) were titrated by adding graded concentrations of CD8+ cells to autologous CD8-depleted peripheral blood mononuclear cells (PBMC), or CD4+ cells to CD8- 4- PBMC, respectively. Following culture with pokeweed mitogen (PWM), numbers of CD5+ and CD5- immunoglobulin-secreting cells were determined using a combination of rosetting with anti-CD5-coated Dynabeads and reverse haemolytic plaque formation (Jones, 1990). Of 11 RA patients studied, eight had slightly reduced suppressor activity for CD5+ and CD5- IgM-secreting cells, and three with active disease and high serum levels of C-reactive protein, could not suppress IgG, IgA or IgM secretion by either B subset. Helper activity for both CD5+ and CD5- B cells was slightly but significantly increased in RA patients. One of eight patients with IgAN could not suppress IgG, IgA or IgM production by CD5+ or CD5- B cells, and all IgAN patients required strikingly fewer CD4+ cells for PWM-induced activation of CD5+ and CD5- B cells than controls. It was concluded that in two immunologically mediated diseases in which some patients have raised numbers of circulating CD5+ B cells, aberrant T-regulation affects CD5+ and conventional CD5- B cells equally.  相似文献   
105.
In the anesthetic management of five patients undergoing excision of pheochromocytoma, adenosine triphosphate (ATP) was used for the purpose of regulating systemic arterial pressure during the period of tumor manipulation. ATP was administered at doses of 0.05–0.4mg/kg/min. Systemic arterial pressure showed a significant decrease from 162 ± 17/103 ± 11mmHg before manipulation to 136 ± 21/81 ± 10mmHg during the manipulation period. The plasma catecholamine levels showed significant increases in this period. Immediately after excision, the systemic arterial pressure was maintained at normal levels (118 ± 13/75 ± 16mmHg) by fluid replacement and discontinuation of ATP administration, subsequently becoming 129 ± 19/79 ± 16mmHg. The heart rate was very stable and tachycardia did not ocurr during the manipulation period. Only one arrhythmic episode ocurred in one patient. The systemic vascular resistance index was significantly lower during the manipulation period than before it. It was therefore considered that ATP was useful as an agent for controlling arterial pressue during the anesthesia for pheochromocytoma.(Murata K, Sodeyama O, Ikeda K et al.: Prevention of hypertensive crisis with ATP during anesthesia for pheochromocytoma. J Anesth 1: 162–167, 1987)  相似文献   
106.
目的:探讨治疗创伤对高血压性脑出血患者血糖及按期预后的影响。方法:采用局麻血肿穿刺抽吸治疗(治疗组32例)及全麻外科手术血肿清除治疗(对照组30例),比较术后的血糖变化,结果:治疗组血肿穿刺抽吸后血糖高峰值水平显著低于对照组(P<0.01),而治疗后第1,2,周血糖降至正常者治疗组显著高于对照组(P<0.05),病死率治疗组6.25%,对照组26.7%),两组比较差异显著(P<0.05),结论:高血压性脑出血患者血肿穿刺抽吸治疗较外科手术血肿清除治疗有血糖峰值低,恢复正常的速度快,病死率低,对脑组织的损伤小等优点,值得临床推广。  相似文献   
107.
为探讨氯沙坦治疗1个月后对老年高血压病患者肾功能的影响,应用生化及放射免疫分析技术测定34例老年高血压患者服用氯沙坦前后的肾功能指标,并进行自身对照。结果显示,治疗前后血浆尿素氮(BUN)、肝酐(Cr)、尿酸(UA)、尿白蛋白、血IgG蛋白、血及尿β2-微球蛋白均无显著性差异(P>0.05)。提示氯沙坦对老年高血压病患者的肾功能无不良影响,为一安全、有效的降压药。  相似文献   
108.
目的 探讨川芎嗪、山莨菪碱、蝮蛇抗栓酶及卡托普利对实验大鼠糖尿病肾病 (DN)的预防作用。方法 SD大鼠 6 0只 ,分为正常对照组、糖尿病组及各糖尿病治疗组。以四氧嘧啶腹腔内注射制成糖尿病模型。各治疗组分别给予上述药物治疗 ,每周 5次 ,共 14周。取肾脏行光镜和电镜检查 ,并进行图像分析 ,同时测定蛋白糖基化产物 (GP)。结果 与糖尿病组比较 ,各治疗组肾组织中水平明显降低 (P <0 .0 1) ;除蝮蛇抗栓酶组外 ,其他治疗组大鼠肾小球截面积亦明显缩小 (P <0 .0 5 ) ;糖尿病组大鼠肾小球基底膜显著不均匀增厚 ,而各治疗组病变较轻 ,尤以卡托普利组疗效最为明显。结论 改善微循环、血液流变学及血流动力学治疗可减慢实验大鼠DN的进展。  相似文献   
109.
细胞凋亡在阿霉素大鼠肾病模型中的作用   总被引:2,自引:0,他引:2  
目的:探讨细胞凋亡在阿霉素肾病中的作用及其机制。方法:将30只体重250-300g的Wistar雄性大白鼠随机分为3组,给模型组和SOD组一次性尾静脉注射阿霉素7.0mg/kg,SOD组于注射阿霉素30min后,每天尾静脉注射超氧化物歧化酶(SOD)1.8mg/kg,对照组注射等量生理盐水,于实验第7天,第14天,第28天分别用代谢笼留取24h尿液,测定尿蛋白,第28天末处死动物,取贤皮质做常规病理检查,电镜检查,并用原位末端标记法检测肾小球,肾小管细胞凋亡情况,肾皮质匀浆丙二醛(MDA)及谷胱甘肽过氧化物酶(GSH-Px)水平分别用硫代巴比妥酸比色法,还原型谷胱甘肽消耗法测定。结果:模型组肾小球,肾小管细胞凋亡数及肾皮质MDA水平明显高于对照组(P<0.01),GSH-Px水平则明显低于对照组(P<0.01),SOD组肾小球,肾小管,细胞凋亡数及肾皮质MDA水平明显低于模型组(P<0.01),GSH-Px水平则明显高于模型组(P<0.01),结论:阿霉素肾病鼠发病与病鼠肾小球,肾小管细胞亡有密切关系,而病鼠肾小球,肾小管细胞凋亡与氧自由基(OFR)有关。  相似文献   
110.
按照血管紧张素转换酶 (ACE)基因插入 /缺失多态性不同 ,将 92例 2型糖尿病肾病患者分为II型组 31例 ,ID型组 30例及DD型组 31例。用苯那普利治疗 6个月后 ,观察治疗前后各组的尿白蛋白排泄率 (UAER)、平均动脉压 (MABP)、肌酐清除率 (Ccr)及ACE的变化。结果 :苯那普利治疗后 3组UAER、MABP、ACE均下降 ,以II型组下降幅度最大 (分别为 58.6%、2 .87kPa和 72 .3% ) ,DD型组下降幅度最小 (P <0 .0 5) ;而Ccr在DD型组下降幅度最大 ,II型组下降幅度最小 (P <0 .0 5) ;多元线性逐步回归分析显示 :ACE基因型对UAER下降率有显著回归效果(R2 =0 .72 ,P <0 .0 0 1 )。提示 :ACE基因型影响血管紧张素转换酶抑制剂 (ACEI)对糖尿病肾病的疗效 ,II基因型患者对ACEI治疗更为敏感。  相似文献   
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