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51.
Antigenicity and immunogenicity of the tegumental outer membrane of adult Schistosoma mansoni 总被引:2,自引:0,他引:2
The tegumental membranes of adult Schistosoma mansoni have been isolated and purified and shown to function as potent immunogens; they elicit an essentially identical immune response in rabbits, rats and mice. Anti-membrane antisera harvested from these animals consistently recognized common antigens, of relative molecular weight (mol. wt) 32 000 and 20 000, on the surface of young schistosomula, 5 day old lung worms and adult worm purified membranes. An additional molecule of 25 000 mol. wt was present on the surface of lung worms and adult worm membranes and was specifically recognised by serum from chronically infected mice and by serum from rabbits inoculated with adult worm purified membranes. The concept of antigenic identity between developmental stages that parasitize the mammalian host was further substantiated by the observation that anti-membrane antiserum bound to live schistosomula, lung worms and adult parasites as measured by indirect immunofluorescence. In complement-mediated in vitro cytotoxicity assays, the sera from rabbits inoculated with either adult worm purified membranes, or the 32 000 mol. wt antigen partially purified from adult worm membranes, mediated levels of schistosomula killing as high as those obtained with sera from chronically infected mice. These rabbit antisera also promoted eosinophil adherence and killing of newly transformed schistosomula, but lung stage parasites, despite binding the anti-membrane antiserum, were refractory to both humoral and cellular cytotoxicity. The significance of antigenic identity is discussed in relation to the concept of concomitant immunity. 相似文献
52.
《Ultrastructural pathology》2013,37(2):49-61
To evaluate the contribution of electron microscopy to the final diagnosis of glomerulopathies, the authors established a prospective study during the first semester of 2006. A total of 52 kidney biopsies were performed with 3 samples for light microscopy, immunofluorescence, and electron microscopy. Among these renal biopsies, only 20 were examined with electron microscopy because the diagnosis made on the basis of conventional methods had remained unclear or doubtful. In 18 cases, electron microscopy was undertaken for the investigation of primary kidney disease. The 2 remaining cases were transplant biopsies. In this series of 20 patients, there were 3 children with an average age of 9 years and 17 adults with an average age of 35.5 years. Fifteen patients (75%) were nephrotic. The study revealed that electron microscopy was essential for diagnosis in 8 cases (40%) and was helpful in 12 cases (60%). In conclusion, the results showed that the ultrastructural study provides essential or helpful information in many cases of glomerular diseases, and therefore electron microscopy should be considered an important tool of diagnostic renal pathology. As was recommended, it is important to reserve renal tissue for ultrastructural study unless electron microscopy can be routinely used in all biopsies. Thus, this technique could be performed wherever a renal biopsy has to be ultrastructurally evaluated. 相似文献
53.
《Ultrastructural pathology》2013,37(6):260-264
ABSTRACTTo determine the role of immunofluorescence (IF) and electron microscopy (EM) in the evaluation of renal biopsies in a developing country, the authors carried out a study in 200 patients with nephrotic syndrome. Renal biopsies were studied by light microscopy, IF, and EM. IF study was useful in all, being essential in 23.5% and helpful in remaining cases. EM was useful in 94.5% cases, being essential in 43% and helpful in 51.5% cases. The results demonstrate that IF and EM are essential in the evaluation of renal biopsies in nephrotic syndrome and these should be employed in the pathologic evaluation of renal biopsies. 相似文献
54.
Light-chain deposition disease (LCDD) of the kidney is defined as deposition of monotypic light chains (LC) within glomerular (GBM) and tubular (TBM) basement membranes. The morphologic features of pure renal LCDD have been presented only in case reports or small series. The aim of this study was to perform a comprehensive evaluation of the light (LM), immunofluorescence (IF), and electron microscopic (EM) features of pure renal LCDD in a large series of biopsies. Out of 46 cases assembled, 42 had multiple myeloma, 2 had monoclonal gammopathy of unknown significance, and in 2 patients no lymphoproliferative disease was identified. The most common LM lesion of LCDD, nodular glomerulosclerosis, was present in only 14 (30%) cases. GBM and/or TBM thickening was found in 3 (6%), mild to moderate mesangial matrix increase in 12 (23%), and unremarkable glomeruli and tubules were seen in 15 (32%) cases. Forty-two had IF and 40 (92%) showed characteristic linear LC immunoreactivity (24 kappa, 16 lambda) along GBM and/or TBM. Among 39 cases in which IF and EM was available, 25 (64%) were positive by both. Two (6%) were negative by IF, but had deposits by EM. In 12 (30%) with immunoreactivity to LC (4 kappa, 8 lambda), no deposits were identified ultrastructurally. This study shows heterogeneous LM lesions in pure LCDD cases. LM alone may be suspicious but not diagnostic of LCDD. Immunofluorescence is more sensitive than EM for detection of LC for the definitive diagnosis of LCDD. This study supports the importance of utilizing kappa and lambda stains in the routine IF panel for diagnosis of LCDD. 相似文献
55.
目的:探讨小鼠神经系统发育过程中脊髓成熟神经元迁移与血管发育之间的关系。方法:不同年龄小鼠共计75只,应用免疫荧光及墨汁灌注的技术,标记小鼠胚胎E17到P30脊髓神经元和血管。结果:大约在胚胎E17左右,小鼠脊髓灰质内开始出现NeuN阳性的神经元,白质中神经元较少,且此时灰质和白质内血管分布均匀,管径一致,分支较少。随着年龄的增长,脊髓周围的神经元不断向内迁移,灰质内NeuN阳性的神经元数先增多后减少且血管体密度先增加后减小,而白质内的神经元持续减少,血管逐渐稀疏。P14以后,脊髓灰质内的血管密度明显高于白质内的血管密度。同时,研究中还发现部分NeuN阳性细胞紧贴着血管分布。结论:在小鼠脊髓的发育过程中,NeuN阳性细胞由脊髓周围逐渐向中心迁移,和脊髓灰质H形态的形成密切相关。同时,血管扮演着重要的角色,它可能通过与神经元的相互作用,引导神经元的迁移,并且为神经元的迁移提供路径和支架。 相似文献
56.
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58.
目的:探讨糖尿病(DM)大鼠和正常大鼠角膜上皮修复过程中紧密连接蛋白 occludin 重塑的特点。方法90只 SD 大鼠随机分为 DM组和正常对照组(NC)各45只(DM组均高脂喂养),通过腹腔注射链脲佐菌素(STZ)诱导形成Ⅱ型 DM大鼠模型,于损伤后0 h(未损伤),16、48、72、120 h (每组5只)处死大鼠取角膜。间接免疫荧光染色和 Western blot 法观察 occludin 蛋白在损伤修复过程中的变化。结果DM大鼠角膜上皮损伤愈合率较 NC 组大鼠明显延迟,DM组和 NC 组大鼠角膜上皮 occludin 蛋白在损伤后16、48 h 表达差异有统计学意义(P <0.05),在损伤后0、72、120 h 表达差异无统计学意义。结论糖尿病可影响大鼠角膜上皮创伤修复过程中紧密连接蛋白 occludin 蛋白的表达。 相似文献
59.
Xiao-Jing Yuan Yu-Jun Wei Qiang Ao Kai Gong Jian-Yong Wang Qiang-San Sun Ling Zhang Zun-Cheng Zheng Lin Chen 《International journal of clinical and experimental pathology》2015,8(7):7849-7858
To explore the relationship of peripheral nerve ultrastructure and its associated protein expression in experimental autoimmune neuritis (EAN). EAN was established in Lewis rats using an emulsified mixture of P0 peptide 180-199, Mycobacterium tuberculosis, and incomplete Freund’s adjuvant. Rats immunized with saline solution were used as a control group. Sciatic nerve ultrastructure and immunofluorescence histopathology were measured at the neuromuscular severity peak on day 18 post-induction. Cell-specific protein markers were used for immunofluorescence histopathology staining to characterize sciatic nerve cells: CD3 (T cell), Iba-1 (microglia), S100 (myelin), and neurofilament 200 (axon). The results showed that swelling of the myelin lamellae, vesicular disorganization, separation of the myelin lamellae, and an attenuation or disappearance of the axon were observed by transmission electron microscopy in the EAN group. CD3 and Iba-1 increased significantly in the structures characterized by separation or swelling of the myelin lamellae, and increased slightly in the structures characterized by vesicular of the myelin lamellae, S100 decreased in the structures characterized by vesicular disorganization or separation of the myelin lamellae. And neurofilament 200 decreased in the structures characterized by separation of the myelin lamellae. Furthermore, we found that Iba1 were positive in the myelin sheath, and overlapped with S100, which significantly indicated that Schwann cells played as macrophage-like cells during the disease progression of ENA. Our findings may be a significant supplement for the knowledge of EAN model, and may offer a novel sight on the treatment of Guillain-Barré syndrome. 相似文献
60.