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61.
The lifespan of antigen-bearing dendritic cells (DCs) is determined by signals from pathogens and T cells. These signals regulate DC survival by modulating expression of Bcl-2 family proteins. Toll-like receptors and T cell costimulatory molecules both trigger a DC survival pathway that is dependent on Bcl-x(L). However, Toll-like receptors uniquely increase expression of Bim and trigger cell death by a pathway that is blocked by Bcl-2. This pathway serves as a molecular 'timer' that sets the lifespan of DCs and regulates the magnitude of T cell responses in vivo. Thus, signals derived from the innate and acquired immune systems control DC lifespan and immunogenicity by distinct molecular mechanisms. 相似文献
62.
运用敏感的B_9细胞增殖试验检测了81例多发性骨髓瘤(MM)患者血清IL-6活性,同时分析了标本的几种急性相蛋白含量,结果表明,68%MM患者血清中IL-6活性大于5μ/ml(正常对照为5μ/ml以下),几种急性相蛋白中C-反应性蛋白(CRP)在MM时升高(P<0.01),平均达正常对照组的17倍以上,MM患者补体C_4与正常对照组无差异(p>0.05),C_3、白蛋白及转铁蛋白在MM时分别比正常下降24.42%、38.83%和32.80%,且与疾病分期有关,在血清IL-6大于5μ/ml的55例中,IL-6活性与CRP、C_3、白蛋白的相关系数分别为0.46,-0.34和-0.29,IL-6与转铁蛋白浓度相关不明显。本文结果提示:CRP、C_3及白蛋白等含量的变化可作为反映MM病情的简易而敏感的指标。 相似文献
63.
Fas cDNA克隆、表达及重组蛋白纯化的研究 总被引:1,自引:0,他引:1
目的:获得高质量及充足的Fas重组蛋白。方法:采用PCR构建表达重组质粒,亲和层析纯化Fas重组蛋白,ELISA检测其免疫学功能。结果:①PCR扩增获得目的片段约 470 bp。②Sanger双脱氧链终止法测序表明,该 DNA序列仅 174位由A→G突变,属于同义突变,与已知的Fas膜外区氨基酸完全一致。③重组质粒经IPTG诱导有一蛋白得以表达,其目的融合蛋白占细菌总蛋白的17. 4%,分子量约为 34.3 kD。④经 Factor Xa切割 Fas融合蛋白,纯化获得 Fas重组蛋白,Western印迹出现特异性Fas蛋白带,分子量为21.3kD,与预测结果相吻合。⑤ELISA检测 Fas重组蛋白,具有抗体的免疫学活性。结论:成功地表达并纯化了Fas重组蛋白,解决了Fas不易获得的难题,为研究Fas提供了良好的实验材料。 相似文献
64.
目的探讨培养神经元缺氧后蛋白激酶A(PKA)活性变化及其与神经元缺氧凋亡的关系。方法建立体外培养W istar大鼠胎鼠皮层神经元模型及培养神经元缺氧模型,用不同浓度的PKA抑制剂(Rp-cAMP),在不同的缺氧时相点观察神经元细胞膜和细胞质中PKA的活性、Bc l-2和TUNEL表达的规律。结果随着缺氧时间的延长,培养神经元细胞膜PKA的活性显著增加,Bc l-2表达降低,TUNEL荧光染色阳性率及平均荧光强度显著升高。而应用Rp-cAMP后细胞凋亡情况显著减轻。结论PKA和Bc l-2均参与了缺氧神经元凋亡;PKA抑制剂Rp-cAMP可减轻缺氧神经元凋亡,且该作用与Bc l-2表达降低有关;PKA的激活在缺氧神经元凋亡中起促发作用。 相似文献
65.
IFN-γ在沙眼衣原体呼吸道感染中免疫防御机制的探讨 总被引:1,自引:0,他引:1
目的:检测与IFN-γ作用相关的酶吲哚胺2,3二氧化酶(IDO)、诱导性一氧化氮合成酶(iNOS)和NADPH氧化酶(ox)gp91在沙眼衣原体呼吸道感染中的表达及与机体防御的关系,探讨衣原体感染中IFN-γ免疫防御作用的机制.方法:用沙眼衣原体小鼠肺炎株(MoPn)通过鼻腔感染C57BL/6(H-2b)小鼠,用过氧化物酶连接的鼠抗衣原体脂多糖单抗染色HeLa 229细胞,检测衣原体在肺组织的生长;用RT-PCR检测衣原体感染后第7及14天小鼠肺组织IFN-γ、IDO、iNOS和gp91NADPH ox mRNA表达.结果:MoPn呼吸道感染后小鼠肺组织匀浆衣原体活性测定,于感染后第2天,HeLa 229细胞内可见有衣原体包涵体生长,IFU值增高,于感染后第7天IFU达最高水平,以后逐渐下降,至感染后21天基本恢复到基线水平.与未感染的对照组比较,Th1细胞因子IFN-γ于感染后第7天表达显著增高,感染后14天有所降低,但仍维持较高水平;同时衣原体感染可显著诱导与IFN-γ作用相关的三种酶IDO、iNOS和gp91 NADPH ox在小鼠肺组织的表达,感染后第7及14天,IDO,iNOS及gp91 NADPH ox的表达与对照组比较均有显著差异,其中IDO和gp91 NADPH ox于感染后第7天mRNA表达增高显著(P<0.01),14天略有下降(P<0.05).结论:衣原体呼吸道感染诱导Th1细胞因子IFN-γ mRNA高表达,参与宿主对衣原体的清除及机体免疫防御,此作用可能与其相应的酶IDO、iNOS和gp91 NADPH ox表达增高有关. 相似文献
66.
A role for hyaluronan in macrophage accumulation and collagen deposition after bleomycin-induced lung injury 总被引:6,自引:0,他引:6
Savani RC Hou G Liu P Wang C Simons E Grimm PC Stern R Greenberg AH DeLisser HM Khalil N 《American journal of respiratory cell and molecular biology》2000,23(4):475-484
Elevated concentrations of hyaluronan (HA) are associated with the accumulation of macrophages in the lung after injury. We have investigated the role of HA in the inflammatory and fibrotic responses to lung injury using the intratracheal instillation of bleomycin in rats as a model. After bleomycin-induced lung injury, both HA content in bronchoalveolar lavage (BAL) and staining for HA in macrophages accumulating in injured areas of the lung were maximal at 4 d. Increased HA in BAL correlated with increased locomotion of isolated alveolar macrophages. HA-binding peptide was able to specifically block macrophage motility in vitro. Importantly, systemic administration of HA-binding peptide to rats before injury not only decreased alveolar macrophage motility and accumulation in the lung, but also reduced lung collagen alpha (I) messenger RNA and hydroxyproline contents. We propose a model in which HA plays a critical role in the inflammatory response and fibrotic consequences of acute lung injury. 相似文献
67.
In this article, we proposed a multifunctional telemedicine system supporting both telediagnosis and teleconsultation services. We attempted not only to insure that the implementation of this system satisfied most requirements, but also to evaluate the impact of the system. With regard to system architecture, we designed a unified multimedia database to store all types of data and used two kinds of network (ATM and ISDN) for different possible applications. As for data transmission, the REFRESH and PREFETCH mechanisms were implemented to enhance data transfer efficiency. A total of 1107 consultations employing the telemedicine system were performed during the past 3 years. This technology was used most frequently for radiology consultation (32.7%, n = 362) and ultrasonic examination (19.5%, n = 216). An evaluation of the impact on diagnosis (507 valid cases) indicated that the diagnosis in 80 cases (15.78%) were altered on the basis of second opinions from a medical center; and the number of patients transferred to the medical center was reduced from 24 (4.7%) to eight cases. Most of the rural-site physicians (97%) thought that they did benefit from specialists' experience and knowledge via the telemedicine system. Based on 431 valid questionnaires, the number of the patients with confidence in the telemedicine system at their local healthcare center increased from 72.6% to 87.5%. Overall, more than 90% of patients and physicians believed that the system was valuable and provided satisfactory services. 相似文献
68.
TCRVβ7.1基因修饰T细胞对乳腺癌细胞杀伤作用的研究 总被引:1,自引:1,他引:1
目的:观察TCPVβ7.1基因转染前后正常人外周血淋巴细胞对乳腺癌细胞株杀伤活性的影响。方法:脂质体包裹PdWA3.1vβ7.1后转染健康人PBMC,流式细胞仪检测PdWA3.1Vβ7.1基因表达,改良MIT法检测TCRVβ7.1基因转染前后正常人外周血淋巴细胞对乳腺癌细胞株杀伤活性。结果:TCRVβ7.1基因转染可显著增加正常人PBMC该基因表达,转染前后正常人外周血淋巴细胞对乳腺癌细胞株杀伤活性有显著性差异。结论:用TCR基因修饰可明显提高正常人PBMC对乳腺癌细胞杀伤作用。 相似文献
69.
抗SARS-CoV抗原的人源Fab段噬菌体抗体库的构建 总被引:6,自引:1,他引:6
目的 :利用抗SARS冠状病毒IgG抗体阳性的SARS康复患者外周血淋巴细胞 ,构建人源Fab段抗体文库。方法 :制备外周血淋巴细胞总RNA ,逆转录成cDNA。以其为模板 ,利用针对家族特异性Ig基因的引物扩增重链Fd段和轻链基因 ,并重组到噬菌粒载体pComb3中 ,将重组噬菌粒载体电转化大肠杆菌XL 1Blue,酶切鉴定抗体库的重组率 ,并测定噬菌体抗体库的库容量。结果 :构建了源于SARS康复患者血清中抗Fab段的抗体文库 ,轻链、重链Fd段基因的重组率分别为91%和 75 % ,库容量为 7.2 3× 10 7。结论 :成功地构建了抗SARS CoV抗原的人源Fab段噬菌体抗体库 相似文献
70.
Anthony Xiang Wei Hou Sina Rashidian Richard N Rosenthal Kayley Abell-Hart Xia Zhao Fusheng Wang 《JMIR Public Health and Surveillance》2021,7(4)
BackgroundOpioid overdose-related deaths have increased dramatically in recent years. Combating the opioid epidemic requires better understanding of the epidemiology of opioid poisoning (OP) and opioid use disorder (OUD).ObjectiveWe aimed to discover geospatial patterns in nonmedical opioid use and its correlations with demographic features related to despair and economic hardship, most notably the US presidential voting patterns in 2016 at census tract level in New York State.MethodsThis cross-sectional analysis used data from New York Statewide Planning and Research Cooperative System claims data and the presidential voting results of 2016 in New York State from the Harvard Election Data Archive. We included 63,958 patients who had at least one OUD diagnosis between 2010 and 2016 and 36,004 patients with at least one OP diagnosis between 2012 and 2016. Geospatial mappings were created to compare areas of New York in OUD rates and presidential voting patterns. A multiple regression model examines the extent that certain factors explain OUD rate variation.ResultsSeveral areas shared similar patterns of OUD rates and Republican vote: census tracts in western New York, central New York, and Suffolk County. The correlation between OUD rates and the Republican vote was .38 (P<.001). The regression model with census tract level of demographic and socioeconomic factors explains 30% of the variance in OUD rates, with disability and Republican vote as the most significant predictors.ConclusionsAt the census tract level, OUD rates were positively correlated with Republican support in the 2016 presidential election, disability, unemployment, and unmarried status. Socioeconomic and demographic despair-related features explain a large portion of the association between the Republican vote and OUD. Together, these findings underscore the importance of socioeconomic interventions in combating the opioid epidemic. 相似文献