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991.
992.
Min K Hong SM Kim KR Ro JY Park MJ Kim JS Kim JM Jung HC Yu E 《Pathology, research and practice》2003,199(1):1-8
Intramucosal Helicobacter pylori (H. pylori) has been described in biopsy tissues and culture systems. However, the association of intramucosal H. pylori with histopathologic features has not been evaluated. The purpose of this study is to investigate the relationship between intramucosal H. pylori and inflammatory reactions in H. pylori infection. In 113 randomly selected human gastric biopsies and 20 murine stomachs, which were inoculated with SSI every day for a week, immunohistochemical analysis for intramucosal H. pylori was done and correlated with histologic parameters. Electron microscopic examination was done on murine stomachs. H. pylori infection was present in 104 gastric biopsies and 17 murine stomachs. Intraepithelial immunopositivity for H. pylori was detected in 27 of 104 (26%) biopsies and in 11 of 17 (65%) murine stomachs. Lamina proprial immunopositivity for H. pylori was present in 51 of 104 (48%) biopsies. Neutrophil-associated immunopositivity for H. pylori was observed in 22 of 90 (24%) biopsies with H. pylori chronic active gastritis. Lamina proprial and neutrophil-associated immunopositivity for H. pylori correlated significantly with the density of H. pylori and the grade of acute inflammatory reaction in H. pylori gastritis. Intramucosal location of H. pylori itself or its antigen is closely associated with acute inflammatory reactions and may play an important role in establishing a persistent infection in chronic H. pylori gastritis. Furthermore, lamina proprial and/or neutrophil-associated H. pylori appears to be more important than intraepithelial H. pylori in acute inflammatory reactions of H. pylori gastritis. 相似文献
993.
The increased incidence of thyroid carcinomas in familial adenomatous polyposis (FAP) patients is well recognised. These thyroid neoplasms display distinctive clinicopathological features and generally show good prognostic outcome. Recently, unusual sporadic tumours that share the morphological features of FAP-associated thyroid carcinomas have also been described. In this report, we document a case of a thyroid tumour in a previously well, 46-year-old female. Histology revealed a circumscribed neoplasm composed of tubular, papillary, cribriform and solid areas. The pseudostratified columnar tumour cells showed occasional nuclear grooves and rare nuclear inclusions. Immunohistochemistry showed positive staining with antibodies to cytokeratin AE1/AE3, oestrogen and progesterone receptor proteins. Focal immunoreactivity was also noted with antibodies to thyroglobulin, epithelial membrane antigen, 34betaE12 and cytokeratin CK7. The absence of polyps on colonoscopy and germline mutation in the adenomatous polyposis coli (APC) gene provides evidence that this tumour represents the sporadic counterpart of FAP-associated thyroid carcinoma. The patient is well with no evidence of disease 7 months following resection of the tumour. The differential diagnoses and molecular genetics of this unusual tumour are discussed. 相似文献
994.
The critical role of ocular-infiltrating macrophages in the development of choroidal neovascularization 总被引:9,自引:0,他引:9
Tsutsumi C Sonoda KH Egashira K Qiao H Hisatomi T Nakao S Ishibashi M Charo IF Sakamoto T Murata T Ishibashi T 《Journal of leukocyte biology》2003,74(1):25-32
Choroidal neovascularization (CNV) is directly related to visual loss in some eye diseases, such as age-related macular degeneration. Although several human histological studies have suggested the participation of macrophages in CNV formation, the precise mechanisms are still not fully understood. In this study, we elucidated the role of ocular-infiltrating macrophages in experimental CNV using CCR2 knockout (KO) mice, wild-type mice, and C57BL/6 (B6) mice. CCR2 is the receptor of monocyte chemoattractant protein-1, and the number of infiltrating macrophage and the area of CNV were significantly reduced in CCR2 KO mice. Enriched ocular-infiltrating macrophages from B6 mice actually showed angiogenic ability in a dorsal air sac assay. Moreover, their expression of class II, CD40, B7-1 and B7-2 molecules, and the mRNA for potential angiogenic factors, such as vascular endothelial growth factor, basic fibroblast growth factor, and tumor necrosis factor alpha, was also observed. Collectively, we conclude that ocular-infiltrating macrophages play an important role in CNV generation. 相似文献
995.
996.
Abnormal protein aggregation is emerging as a common theme in the pathogenesis of neurodegenerative disease. Our previous studies have shown that overexpression of untranslated light neurofilament (NF-L) RNA causes motor neuron degeneration in transgenic mice, leads to accumulation of ubiquitinated aggregates in degenerating cultured motor neurons and triggers aggregation of NF-L protein and co-aggregation of mutant SOD1 protein in neuronal cells. Here, we report that p190RhoGEF, an RNA-binding protein that binds to a destabilizing element in NF-L mRNA, is involved in aggregation of NF-L protein and is implicated in the pathogenesis of motor neuron degeneration. We show that p190RhoGEF co-aggregates with unassembled NF-L protein and that co-aggregation is associated with down-regulation of parent NF-L mRNA in neuronal cells. Co-expression of NF-M increases NF assembly and reduces RNA-triggered aggregation as well as loss of solubility of NF-L protein. siRNA-induced down-regulation of p190RhoGEF not only reduces aggregation and promotes assembly of NF-L and NF-M, but also causes reversal of aggregation and recovery of NF assembly in transfected cells. Examination of transgenic models of motor neuron disease shows that prominent aggregates of p190RhoGEF and NF-L and down-regulation of NF-L expression occur in degenerating motor neurons of mice expressing untranslated NF-L RNA or a G93A mutant SOD1 transgene. Moreover, aggregates of p190RhoGEF and NF-L appear as early pathological changes in presymptomatic G93A mutant SOD1 transgenic mice. Together, the findings indicate that p190RhoGEF is involved in aggregation of NF-L protein and support a working hypothesis that aggregation of p190RhoGEF and NF-L is an upstream event triggering neurotoxicity in motor neuron disease. 相似文献
997.
目的 应用核酸扩增产物测定的固相杂交酶联显色法(RT-PCR-ELISA)检测甲肝减毒活疫苗病毒滴度。方法 应用RT-PCR-ELISA。将标记有生物素的寡核苷酸引物所扩增的疫苗病毒基因产物。与微孔反应板上的特异性探针进行快速杂交,通过辣根过氧化物酶标记的链亲和素进行酶联显色。读取吸光度(A值)。判断结果。应用此法检测了11批甲肝活疫苗滴度。并与常规细胞培养法(CCID50)比较。结果 本方法与细胞培养法的敏感性相仿,具有简便、快速、特异的优点。结论 RTPCR-ELISA法有望代替常规细胞培养法应用于甲肝减毒活疫苗病毒滴度的检测。 相似文献
998.
目的 评价解剖钢板结合连续被动运动(CPM)功能锻炼在治疗胫骨平台骨折中的应用价值.方法 2003年5月至2005年10月本院34例胫骨平台骨折行解剖复位、解剖钢板内固定并在术后进行CPM功能锻炼.结果 术后对患者行X线检查示骨折实现解剖复位或接近解剖复位.23例患者经5~30个月随访骨折均愈合,无植骨坏死发生.CPM功能锻炼后运动功能恢复优良率为82.6%(19/23).结论 采用关节面的解剖复位、解剖钢板及牢固固定后配合术后CPM功能锻炼对于胫骨平台骨折有很好的疗效. 相似文献
999.
慢性乙型肝炎患者血清HBV DNA水平与肝纤维化标志物的关系 总被引:1,自引:0,他引:1
目的研究慢性乙型肝炎患者血清HBV复制水平和肝纤维化血清学标志物的关系。方法入选临床确诊为慢性乙型肝炎的157例患者,其中49例为早期肝硬化,采用荧光定量PCR检测血清HBVDNA水平,放射免疫法和酶免疫法检测肝纤维化血清标志物:透明质酸、层黏蛋白、Ⅲ型前胶原N端肽和Ⅳ型胶原,对血清HBVDNA水平和肝纤维化标志物的关系进行研究分析,并对49例早期肝硬化患者和108例无肝硬化患者的血清HBVDNA及肝纤维化血清标志物水平进行比较。结果慢性乙型肝炎患者的血清HBVDNA水平和肝纤维化标志物水平无显著相关性(P〉0.05),早期肝硬化患者的血清肝纤维化标志物水平显著高于无肝硬化的患者,而HBVDNA水平却低于无肝硬化的患者(P〈0.05)。结论慢性乙型肝炎患者的血清HBVDNA水平和肝纤维化标志物水平无显著相关性。 相似文献
1000.
目的:构建霍乱毒素B亚单位(CtB)和幽门螺杆菌尿素膜通道蛋白(UreⅠ)融合的原核表达质粒pET32a(+)ctB/ure Ⅰ,并初步研究融合蛋白Ct B/Ure Ⅰ的表达特性和免疫特性.方法:PCR从pUC18 ctB中克隆ctB基因,定向在pET32a(+)/ureⅠ的ureⅠ基因5'端插入ctB基因,构建ctB和ure Ⅰ双基因原核表达质粒pET32a(+)ctB/ure Ⅰ,转该质粒于E.coli BL-21(DE3),经酶切和序列分析鉴定工程菌.IPTG诱导表达,HP-His亲和层析纯化,SDS-PAGE和Gel-Pro Analizer4分析,重组蛋白免疫BALB/c小鼠.用Western blot和ELISA分析重组蛋白的免疫特性.结果:工程菌含完整的ctB和ure Ⅰ基因,与相对应基因的序列同源性分别为100%.在22℃,1 mmol/L IPTG诱导4 h后,重组蛋白的表达占菌体总蛋白12%,亲和层析纯化后蛋白纯度为94.3%.Western blot表明重组蛋白分别能与相应的抗体反应,该蛋白免疫小鼠后能产生相应的IgG抗体.结论:成功构建了能表达CtB/Ure Ⅰ蛋白的大肠杆菌表达菌株.对融合蛋白表达和纯化后,初步证明了该重组蛋白有CtB和Ure Ⅰ的双特异反应原性和免疫原性,为研究新型幽门螺杆菌疫苗奠定了坚实的基础. 相似文献