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71.
目的 本研究采用射频热凝毁损腰交感神经节,探讨背根神经节(DRG)Nav1.8磷酸化在大鼠糖尿病痛性周围神经病变中的作用。方法 采用腹腔注射链尿佐菌素诱导糖尿病痛性周围神经病变大鼠模型,取造模成功的大鼠20只,随机分为糖尿病对照组(D组)及交感神经节射频热凝组(R组),每组10只,另取10只同月龄大鼠为正常对照组(C组)。R组大鼠在X光机介导下行右侧L3,4椎旁腰交感神经节射频热凝毁损。分别于射频热凝前、射频热凝后1、2周时,采用von Frey纤维丝测定大鼠右侧后爪对机械性刺激缩足反应的阈值(PWT);射频热凝后2周,采用Western-blotting方法测定DRG细胞Nav1.8蛋白和苏氨酸磷酸化Nav1.8蛋白表达,并采用透射电镜观察大鼠腓肠神经超微病理结构。结果 与C组比较,射频热凝前D组和R组PWT降低(P<0.01)。射频热凝后1~2周,R组较D组PWT升高,但仍较C组降低(P<0.05)。C组髓鞘排列均匀,轴突内可见形态正常的线粒体;D组脱髓鞘明显,髓鞘板层排列紊乱、断裂、肿胀;R组脱髓鞘程度明显减轻,髓鞘板层局部排列紊乱、空泡形成。与C组比较,D组和R组Nav1.8蛋白表达降低(P<0.05),而苏氨酸磷酸化Nav1.8蛋白表达增高(P<0.01);R组苏氨酸磷酸化Nav1.8蛋白表达低于D组(P<0.05)。结论 DRG细胞Nav1.8的磷酸化可能是糖尿病痛性周围神经病变大鼠痛觉过敏形成的机制之一。  相似文献   
72.
73.
The pathogenesis of diabetic neuropathy is incompletely understood. The possibility that humoral neurotoxic factors contribute as a cause of diabetic neuropathy was tested by application of serum from patients with Type 1 and Type 2 diabetes to mouse neuroblastoma cells, which have the characteristics of adrenergic neurons in culture. Serum from patients with Type 1 diabetes and somatic neuropathy significantly inhibited both proliferation and differentiation of neuroblastoma cells, while serum from patients with Type 1 diabetes but no symptoms of neuropathy and patients with Type 2 diabetes and neuropathy had no effect on proliferation, and serum from Type 2 patients only marginally inhibited differentiation. The effects of Type 1 diabetic serum could be reversed by pre-absorption of the serum to neuroblastoma cells, and were independent of glucose levels. Immunoglobulins precipitated from the sera mimicked the effects of whole sera. These results suggest that Type 1 diabetes mellitus causes a change in serum composition, possibly related to autoimmunity, that is capable of contributing to adrenergic autonomic neuropathy in diabetic patients.  相似文献   
74.
异体硬脊膜桥接周围神经缺损的实验研究   总被引:6,自引:1,他引:5  
探讨异体硬脊膜修复周围神经缺损的可行性。方法:采用狗的异体硬脊膜桥接缺损2cm的狗腓总神经,对照组仅切取2cm神经而不作处理。在术后不同时间段作大体观察、神经电生理检测、光镜利电镜检查。结果:再生神经纤维在管腔内呈纵行整齐排列T偕窬宋峤岣弧=崧郏菏5验结果证实异体硬脊膜能成功地引导周围神经再生。  相似文献   
75.
Summary Immunological disturbances with impairment of immune function and a higher incidence of lymphoproliferative disorders and other malignancies have been described in liver cirrhosis patients. To investigate the pathogenetic mechanism(s) involved in such associated we looked for a possible imbalance in peripheral blood T-lymphocyte subpopulations in patients with liver cirrhosis of differing severity. Immunophenotyping and counts of peripheral blood T-lymphocyte subpopulations were carried out using monoclonal antibodies conjugated with different fluorochromes in 31 consecutive cirrhotic patients and 23 matched healthy volunteers. Univariate and multivariate analyses of lymphocyte phenotype counts were performed and odds ratios were computed. Statistically significant associations, according to both univariate and multivariate analyses, were found between case/control status and mean CD3 and CD4 T-lymphocyte counts (P<0.0001). A strong correlation was found between the Pugh’s index and CD3 and CD4 lymphocyte counts, with a clear reduction of these phenotypes with increasing liver cirrhosis. Median CD3 and CD4 values were 2,283 and 1,329/μl respectively among controls and 896, 801, and 492/μl and 515, 514, and 307/μl, respectively in categories A, B, and C of Pugh’s classification. Very high odds ratios were found using the median values of CD3 and CD4 as a threshold. There was a statistically significant decrease for each of the T-cell phenotypes studied (CD2, CD3, CD4, CD8, CD16, CD19, CD20, CD56, CD57) between patients and controls (P<0.0001). The progressive and severity-related decrease in mean peripheral blood CD3 and CD4 counts in liver cirrhosis suggests a progressive impairment of protective immune function and may be a factor facilitating malignancy in cirrhotic patients.  相似文献   
76.
Antiviral cytotoxic memory CD8+ T cells adoptively transferred to mice which are persistently infected with lymphocytic choriomeningitis virus WE or DOCILE initially proliferated extensively; they either caused the death of the recipient or, alternatively, disappeared within a few days. Apparently, the complete and coordinated induction and stimulation by widely distributed viral antigen caused these memory T cells to die before virus had been eliminated from the host. Thus memory T cells are as susceptible to peripheral exhaustion/deletion as unprimed T cells. These results indicate possible limitations of exclusively CD8+ T cell-mediated adoptive immunotherapy against viral infections or tumors.  相似文献   
77.
预变神经段修复神经缺损的实验研究   总被引:5,自引:2,他引:3  
目的探讨不同预变时间组移植神经对神经再生的影响。方法以SD大鼠的不同预变时间组的尺神经作为移植神经,修复其正中神经的缺损。实验侧按移植神经预变时间的不同分为0、1、2、3、4、8周共6组,每组6只SD大鼠。移植后12周,检测实验侧趾屈肌群的张力、最大收缩力、再生神经的形态及神经轴突的截面积。结果用预变1周的尺神经修复正中神经后,其趾屈肌群的张力及最大收缩力的恢复率达到正常对照组的81.1%及85.9%。显微镜下观察,预变1周组和其它各时间组相比,其再生的神经轴突最多,发育最成熟。结论用预变1周的神经段修复神经缺损,其神经再生能力最佳  相似文献   
78.
The diabetic neuropathic ulcer is typically slow to heal and recurrent. Macrovascular insufficiency is usually excluded as foot pulses are present and ankle:brachial pressure ratios are not decreased. These assessments cannot however exclude more distal vascular disease. Digital pressure measurements enable a reliable assessment of the distal peripheral vascular status to be made. The aim of this study was therefore to use toe pressures to assess the contribution of distal ischaemia in the pathogenesis of the neuropathic ulcer. Sixteen diabetic patients with recurrent neuropathic foot ulceration had their toe pressures compared to 10 neuropathic patients without a history of foot ulceration, 10 diabetic control subjects, and 11 normal subjects. Four non-diabetic patients with neuropathy and foot ulceration were also assessed. All subjects had ankle:brachial pressure indices ≧ 1. Toe pressure was assessed using laser Doppler flowmetry to record the return of skin blood flow. The toe:brachial pressure index (TBI) was then calculated. The diabetic patients with a history of recurrent neuropathic ulceration, had the lowest mean TBI, 0.63 ± 0.14 (SD), compared to the non-ulcerated diabetic neuropathy patients, the diabetic control subjects, and the normal subjects. 0.84 ± 0.11, 0.82 ± 0.1, and 0.81 ± 0.07, p < 0.01, respectively. Three of the four non-diabetic patients with neuropathic foot ulceration also had an abnormally low TBI. Reduced toe pressure measurements are thus found to be associated with neuropathic foot ulceration. The contribution of distal ischaemia in the pathogenesis of the diabetic neuropathic foot ulcer needs to be evaluated. One hundred and eight non-insulin-dependent diabetic patients who had been tested for autonomic dysfunction in 1984/85 were re-evaluated 5 years later. Autonomic function was assessed by means of four cardiovascular tests (heart rate variation during deep breathing and standing, and blood pressure variation after standing and sustained handgrip). Eighteen subjects were lost to follow-up; in the 90 patients who completed the study, both the deep breathing and the handgrip test significantly worsened (respectively from 13.7 ± 7.8 to 11.6 ± 6.3 beats min?1 p < 0.01, and from 16.9 ± 8.2 to 12.7 ± 7.1 mmHg, p < 0.001), whereas both the 30:15 ratio and the variation of blood pressure on standing did not change. The impairment of a comprehensive evaluation score (from 2.5 ± 1.7 to 3.0 ± 1.5; p < 0.05) also confirmed the gradual deterioration of autonomic function over the study period.  相似文献   
79.
肾病患儿免疫细胞对肾小球上皮细胞合成基质的影响   总被引:1,自引:0,他引:1  
目的为了明确免疫细胞对肾小球上皮细胞(glomerularepithelialcelGEC)合成功能的直接作用。方法应用肾小球细胞体外培养,同位素掺入及放射免疫技术,以总胶原,层粘连蛋白,Ⅲ型前胶原及Ⅳ型胶原的合成为观察指标,动态研究了不同病理类型原发性肾病综合征(INS)患儿外周血单个核细胞(peripheralbloodmononuclearcelPBMC)对GEC生物功能的影响。结果(1)肾病极期未经激素治疗组(未治组)PBMC上清明显促进了GEC合成层粘连蛋白;(2)未治PBMC上清抑制了GEC合成总胶原;(3)未治组PBMC上清促进了Ⅲ型前胶原的合成,而对Ⅳ型胶原的合成无明显影响;(4)肾病患儿PBMC的上述作用与是否足量激素治疗有关,而与尿蛋白能否阴转、肾组织病理类型、肾病临床类型等无直线相关关系。结论原发性肾病患儿循环免疫细胞可影响GEC合成细胞外基质的功能。免疫细胞的这种活性可被激素治疗改变。  相似文献   
80.
Type 1 diabetes is an autoimmune disease resulting in destruction of pancreatic β cells. Many of the pancreatic β cell autoantigens are also neuronal cell components. Using adrenergic neuroblastoma cells, we have previously demonstrated that humoral mechanisms may contribute to the development of diabetic neuropathy in Type 1 patients. We hypothesize that the toxic factor in Type 1 diabetic serum is an immunoglobulin. When neuroblastoma cells were exposed to immunoglobulins precipitated from serum of Type 1 diabetes patients with neuropathy, cell growth was significantly inhibited by day 5 (3.8 ± 2.4 times 105 cells) compared to cells cultured with immunoglobulins from control (8.2 ± 2.3 times 105 cells) or Type 2 diabetic serum (7.0 ± 3.0 times 105 cells). The inhibitory effect (3.2 ± 0.9 times 105 cells) could be removed from Type 1 diabetic serum by affinity precipitation with protein A-agarose (8.0 ± 0.8 times 105 cells). Mild heat denaturing of the serum reversed the inhibitory effect (3.8 ± 0.9 vs 1.4 ± 1.4 times 105 cells), indicating a requirement for complement. Immunofluorescent labelling with anti-IgG secondary antibody of cells exposed to Type 1 diabetic serum indicated recognition of a membrane-bound antigen. The studies in this report support the hypothesis that autoimmune neuronal destruction may contribute to the development of diabetic autonomic neuropathy in patients with Type 1 diabetes.  相似文献   
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