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901.
902.
马凡综合征两种新的原纤维蛋白-1基因突变 总被引:1,自引:1,他引:1
目的对9例马凡综合征(Marfansyndrome,MFS)患者的原纤维蛋白-1(fibrillin-1,FBN1)基因进行突变筛查,以发现新的FBN1基因突变。方法应用变性高效液相色谱法对MFS患者FBN1基因65个外显子中的35个进行突变筛查,对变性高效液相色谱图形异常的PCR扩增片段用DNA测序鉴定突变位置及性质,并用等位基因特异性PCR以及限制性片段长度多态性分析等方法进一步证实突变。结果在两例MFS患者中发现两种新的FBN1基因突变。其中一种为第34外显子4307~4308位4个碱基TCGT的插入突变(4307insTCGT),另一种为第43外显子5309位的点突变5309G>A。结论FBN1基因移码突变(4307insTCGT)与点突变(5309G>A)分别是这两例MFS患者的发病原因。 相似文献
903.
等离子体表面改性涤纶材料的血浆蛋白吸附与血小板黏附行为研究 总被引:8,自引:0,他引:8
采用等离子体表面接枝改性技术在涤纶 (聚对苯二甲酸乙二醇酯 ,PET)材料表面接枝不同分子量的聚乙二醇 (PEG) ,从表面能与界面自由能的角度分析了血浆蛋白 (纤维蛋白原和白蛋白 )在材料表面的竞争吸附关系 ,结果表明接枝了 PEG长链分子的 PET材料具有优先吸附白蛋白的性质 ,其中接枝 PEG6 0 0 0的 PET优先吸附倾向最明显。预接触白蛋白和纤维蛋白原的 PET材料表面的血小板黏附实验表明 :吸附白蛋白的表面能够显著抑制血小板的黏附和聚集 ,表现出好的血液相容性 ,而吸附了纤维蛋白原的材料表面具有降低血液相容性的性质。 相似文献
904.
Monocyte chemoattractant protein-1 (MCP-1) is a pivotal mediator of angiocentric granuloma formation in glucan-induced pulmonary granulomatous vasculitis. Based on the rationale that mononuclear phagocytes retrieved from granulomas are rich sources of nitric oxide (NO) and that the recruitment of mononuclear phagocytes into lesions abates as granuloma formation slows, we tested the hypothesis that MCP-1 gene expression is regulated by a NO-sensitive mechanism. Preexposure of endothelial cell (EC) monolayers to NO donor compounds markedly reduced cytokine-induced MCP-1 expression and cytosolic-to-nuclear translocation of nuclear factor-kappa B (NF-B), reversed fluctuations in endothelial reduced glutathione (GSH) pools but did not affect cGMP concentrations. The lungs of mice bearing targeted disruptions of the inducible nitric oxide synthase (iNOS) gene exhibited significantly higher concentrations of MCP-1 following glucan infusion than did those of wild-type mice. Cumulatively, these data suggest that NO suppresses MCP-1 expression by blunting the redox changes associated with cytokine-induced EC activation. 相似文献
905.
906.
细胞外信号调节蛋白激酶(ERK)1/2是重要的信号转导分子。现已知在正常动物的中枢神经系统内有其活化形式即磷酸化的ERK1/2(pERK1/2)分子的存在,但其在小鼠脑内的分布目前还没有全面的观察。本研究用免疫组织化学技术(ABC法)研究了pERK1/2样免疫反应阳性产物在脱臼处死的正常小鼠全脑内的分布。结果发现pERK1/2在正常小鼠脑内有广泛的表达,阳性产物主要存在于神经元,亦见于个别白质内的胶质细胞,脑膜及室管膜细胞也有表达。强阳性表达的核团主要有:岛皮质、视听皮质、边缘前皮质、扣带前皮质、海马垂直部、弓状核、蓝斑和小脑Purkinje细胞;中等阳性表达的核团主要有:感觉运动皮质、外侧隔区、内侧杏仁核、皮质杏仁核和外侧杏仁核、丘脑室旁核前部、视交叉上核、穹隆下器、终板血管器、前腹侧视前核和下丘脑背内侧核;弱阳性表达的核团主要有:视上核、下丘脑室旁核大细胞部、下丘脑后区、顶盖前区、室周灰质腹外侧柱、A5区、孤束核和延髓腹外侧网状结构等。本文结果观察到pERK1/2在正常小鼠脑内广泛存在,提示pERK1/2作为重要的信号转导分子,可能参与许多脑区在正常状态下的功能活动,揭示其分布特点为了解其在脑内的多样性功能提供了形态学依据。 相似文献
907.
Elizabeth M Genega Malathy Kapali Marta Torres-Quinones William C Huang Jill S Knauss Li-Ping Wang Puthiyaveettil N Raghunath Christopher Kozlowski Stanley Bruce Malkowicz John E Tomaszewski 《Modern pathology》2005,18(1):11-18
The classification of urothelial neoplasms of the kidney traditionally has been similar to that of urinary bladder tumors. Several years ago, the classification of papillary urothelial neoplasms was revised. The current study focuses on the application of the 1998 World Health Organization (WHO)/International Society of Urological Pathology classification system to 102 renal pelvic urothelial neoplasms and compares it to the 1973 WHO classification scheme. In this study, all tumors were classified as urothelial carcinomas, and the majority (85%) were papillary. Most patients with papillary tumors presented with 'superficial' disease (< or = pT1). With the 1998 system, most papillary carcinomas were high grade, and were more often invasive as compared to low-grade tumors. Only 34% were low-grade papillary tumors and, of these, most (93%) were noninvasive. With the 1973 system, most papillary tumors were grade 2 or 3, with invasion more common in grade 3 tumors. By 1973 criteria, grade 2 tumors were a heterogeneous group; with 1998 criteria, nearly one-half were high grade and the other half low grade. The grade of papillary urothelial carcinomas with both the 1973 and 1998 grading methods was associated with stage (P=0.001). Our study reveals that papillomas and papillary urothelial neoplasms of low malignant potential are uncommon tumors in the kidney. Renal pelvic papillary urothelial neoplasms are most often carcinomas and are more commonly high grade than low grade. Although both the 1973 and 1998 systems showed a significant association with tumor stage, grade 2 papillary carcinomas are a heterogeneous group by 1973 criteria. The 1998 system provides useful information in that it more clearly defines a papillary tumor's grade and selects for a group of tumors, namely low-grade papillary urothelial carcinomas, for which a low likelihood of invasion can be predicted. 相似文献
908.
Effects of omalizumab and budesonide on markers of inflammation in human bronchial epithelial cells.
Yu-Ching Huang Bartlomiej Leyko Marianne Frieri 《Annals of allergy, asthma & immunology》2005,95(5):443-451
BACKGROUND: Many patients with asthma have an IgE-mediated allergic component to the disease. Omalizumab, a monoclonal anti-IgE antibody, has demonstrated clinical efficacy in patients with allergic asthma. The effects of omalizumab on inflammation in asthma are not completely understood. OBJECTIVES: To evaluate the effects of omalizumab on allergen- and growth factor-stimulated proinflammatory cytokine and nitric oxide (NO) production in human bronchial epithelial cells (BECs) and to compare them to the effects of budesonide, a corticosteroid with known anti-inflammatory properties. METHODS: Human BECs were stimulated in duplicate with interleukin 1beta (IL-1beta), 100 U/mL; ragweed, 10 microg/mL; dust mite, 1000 AU; and epithelial growth factor, 40 ng/mL; and either 10(-7) M budesonide or 0.1 microg/mL of omalizumab in a 4% dust mite atopic serum medium for 6 and 24 hours in 5% carbon dioxide at 37 degrees C. Tumor necrosis factor alpha and transforming growth factor betaexpression and production and IL-4, IL-13, and NO production were assayed using gene-specific messenger RNA or sensitive enzyme-linked immunosorbent assays. RESULTS: Omalizumab inhibited the expression and of production proinflammatory cytokines and growth factor in antigen-stimulated BECs at 6 and 24 hours. Production of NO was inhibited at 6 hours and increased at 24 hours by omalizumab and budesonide. CONCLUSIONS: The effects of omalizumab were similar to those of budesonide. These results, consistent with previously reported evidence of anti-inflammatory effects of omalizumab, demonstrate that omalizumab may reduce airway inflammation and probably contributes to decreased airway remodeling in patients with asthma. 相似文献
909.
Liu X Beaty TH Deindl P Huang SK Lau S Sommerfeld C Fallin MD Kao WH Wahn U Nickel R 《The Journal of allergy and clinical immunology》2003,112(2):382-388
BACKGROUND: Increased total serum IgE levels are a common characteristic of atopic disorders. Six potentially functional variants, including C-590T in the IL4 gene, C-1055T and Arg130Gln in the IL13 gene, and Ile50Val, Ser478Pro, and Gln551Arg in the IL4RA gene, have been evaluated for their involvement in the control of total serum IgE levels and related atopic disorders, but the results of these studies have been inconsistent. OBJECTIVE: We examined whether these 6 variants had genotypic effects on total serum IgE levels in 823 unrelated German children from a large infant cohort, the German Multicenter Atopy Study. METHODS: Marginal effect models were used for the analyses of the repeated IgE measurements. Weighted linear regression and family-based tests of association were performed to minimize the possibility of spurious effects caused by selection bias or confounding on the basis of ethnic background. RESULTS: There are significant associations between increased total serum IgE levels and 2 variants in the IL13 gene (P <.005 and.0002 for Arg130Gln and C-1055T, respectively). These genetic effects are unlikely to be due to solely linkage disequilibrium between 2 polymorphisms, population stratification, or nonrepresentative samples. In addition, exposure to maternal smoking appears to modify the above effects on total serum IgE levels. However, no statistical association was observed between this quantitative phenotype and the other 4 variants examined. CONCLUSION: These findings suggest that variants C-1055T and Arg130Gln of the IL13 gene might play an important role on total serum IgE production in this study population. 相似文献
910.
Immunofluorescence technique using HeLa cells expressing recombinant nucleoprotein for detection of immunoglobulin G antibodies to Crimean-Congo hemorrhagic fever virus
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Saijo M Qing T Niikura M Maeda A Ikegami T Sakai K Prehaud C Kurane I Morikawa S 《Journal of clinical microbiology》2002,40(2):372-375
A HeLa cell line continuously expressing recombinant nucleoprotein (rNP) of the Crimean-Congo hemorrhagic fever virus (CCHFV) was established by transfection with an expression vector containing the cDNA of CCHFV NP (pKS336-CCHFV-NP). These cells were used as antigens for indirect immunofluorescence (IF) to detect immunoglobulin G antibodies to CCHFV. The sensitivity and specificity of this IF technique were examined by using serum samples and were compared to those of the IF technique using CCHFV-infected Vero E6 cells (authentic antigen). Staining of the CCHFV rNP expressed in HeLa cells showed a unique granular pattern similar to that of CCHFV-infected Vero E6 cells. Positive staining could easily be distinguished from a negative result. All 13 serum samples determined to be positive by using the authentic antigen were also determined to be positive by using CCHFV rNP-expressing HeLa cells (recombinant antigen). The 108 serum samples determined to be negative by using the authentic antigen were also determined to be negative by using the recombinant antigen. Thus, both the sensitivity and the specificity of this IF technique were 100% compared to the IF with authentic antigen. The novel IF technique using CCHFV rNP-expressing HeLa cells can be used not only for diagnosis of CCHF but also for epidemiological studies on CCHFV infections. 相似文献