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151.
目的评价化学发光微粒子免疫法(chemiluminescence microparticle immunoassay, CMIA)检测临床血清标本梅毒螺旋体抗体的敏感性和特异性。方法用梅毒螺旋体颗粒凝集试验(TVeponema Pallidum particie agglutination test,TPPA)法作为对照标准,采用CMIA法检测2012年11月到12月1200例住院患者的血清标本,并用卡方检验评价两种检测方法对同一个样本的化验结果的一致性。结果1200例血清标本中用CMIA法检出阳性率为11.3%,TPPA法检出阳性率为10. 9% ,以TPPA为标准,CMIA法敏感性为96. 9%,特异性为99. 2%,其中CMIA法检测血清S/CO值〉 4. 00的110例,用TPPA确认107例阳性,阳性预测值(PPV)为97.3%;CMIA法S/C0值在1.0-9.0,TPPA可出现阴性结果。结论CMIA法可替代TPPA法进行梅毒螺旋体抗体检测,对于CMIA法检测S/C0值1. 0-4.0的需进一步复检。 相似文献
152.
Telomere DNA is related to cell aging and cancer genesis because the telomeric region of DNA sequences at chromosome ends are shortened with cell divisions. Therefore, a sensitive and specific detection method is required for the telomere DNA. Here we propose a chemiluminescence (CL)-based method for the sensitive detection of telomere DNA in human cells. In this study, the telomere DNA was amplified by polymerase chain reaction (PCR) using special forward and reverse primers labeled with fluorescein-5-isothiocyanate (FITC) at the 5′ end, and then the FITC-containing PCR products were detected by CL reaction with 3,4,5-trimethoxyphenylglyoxal (TMPG) after electrophoresis followed by Southern blot onto a nylon membrane. The TMPG reagent specifically reacted with guanine moiety in DNA at room temperature and provided CL intensities. The CL intensities from the PCR products could be enhanced approximately 10-fold using FITC-labeled primers as compared with those using nonlabeled primers. The detection limit of the PCR products with the proposed method was 0.3 ng on the membrane. The developed CL method could quantitatively determine the telomere DNA in a small number of human cells (∼350) and gave approximately 10 times higher sensitivity than a conventional fluorescence-based method. 相似文献
153.
154.
A simple colorimetric biosensing technique based on the interaction of gold nanoparticles (AuNPs) with the aptamer was developed for detection of p53, a tumor suppressor protein, in the current study. Aggregation of AuNPs was induced by desorption of the p53 binding RNA aptamer from the surface of AuNPs as a result of the aptamer target interaction leading to the color change of AuNPs from red to purple. The detection limit of p53 protein by the colorimetric approach was 0.1 ng/ml after successful optimization of the amount of aptamer, AuNPs, salts, and incubation time. Furthermore, the catalytic activity of the aggregated AuNPs was greatly enhanced by chemiluminescence (CL) reaction, where the detection limit was enhanced to 10 pg/ml with a regression coefficient of R2 = 0.9907. Here the sensitivity was increased by 10-fold compared with the AuNP-based colorimetric method. Hence, the sensitivity of detection was increased by employing CL, by using the catalytic activity of aggregated AuNPs, on the luminol–hydrogen peroxide reaction. Thus, the combination of colorimetric and CL-based aptasensor can be of great advantage in increasing the sensitivity of detection for any target analyte. 相似文献
155.
Andrea L. Blair Ian A. Cree John Swanson Beck John M. Grange Thomas Kardjito 《FEMS immunology and medical microbiology》1993,7(2):197-204
Abstract We have examined heat-stable opsonins to 4 species of gamma-irradiated mycobacteria ( M. tuberculosis (H37Rv), M. avium (28A), M. scrofulaceum and M. leprae (cd 103)) in complement-depleted sera collected from Indonesian subjects with tuberculosis (106 patients), leprosy (24 patients) and controls (40 hospital workers and 41 factory workers) indirectly by microtitre plate chemiluminescence (CL) assay and compared the results with antibody levels. The results indicate that there is a wide range of opsonic capacity for mycobacteria in complement-depleted sera. There was a poor correlation between the opsonic capacity as measured by CL and the anti-mycobacterial antibody content of sera measured by ELISA, suggesting that anti-mycobacterial antibody has little influence on the uptake of mycobacteria. However, a non-specific heat-stable opsonin appears to be present in some sera. Conversely, some sera from tuberculosis or leprosy patients suppress the production of reactive oxygen species from normal phagocytes in vitro when stimulated with M. tuberculosis . The relevance of this inhibition and the presence of heat-stable opsonins to the pathogenesis of tuberculosis have yet to be determined, but it is possible that the presence of opsonins may inhibit dissemination of tubercle bacilli to other organs. 相似文献
156.
Abstract The human histiocytic lymphoma cell line U937 can be induced to differentiate along the monocyte/macrophage pathway by either phorbol myristate acetate (PMA) or by the combination of retinoïc acid (RA) and 1,25-dihydroxyvitamin D3 (VD). U937 cells treated with either PMA or RA/VD were able to phagocytose Salmonella typhimurium in the presence of non-immune human serum. However, only cells differentiated by RA/VD were capable of developing an oxidative metabolic burst in response to infection. Since the oxidative burst is considered to be a potent antimicrobial mechanism, we investigated its effect on S. typhimurium . The oxidative burst failed to affect either the viability or the multiplication of S. typhimurium suggesting that if plays only a minor role in the host defence against S. typhimurium . 相似文献
157.
目的:蛋白免疫印迹法自发明以来被广泛应用于现代生物学研究中的蛋白质定性和半定量分析。为了提高蛋白免疫印迹法的检测效率,需针对不同蛋白的特性调节相关的实验条件参数。本文旨在探讨免疫印迹法不同参数对小分子蛋白检测效果的影响,从而优化并获得最佳实验条件。方法:比较不同转膜电压和时间、转移缓冲液甲醇含量、不同化学发光剂对小分子蛋白的检测效果。结果:选择20 V、10 min转膜电压和时间所获得的信号显著高于10 V、25 min转膜条件,选择含20%甲醇转移缓冲液所获得的信号显著高于无甲醇转移缓冲液,选择飞克级化学发光剂所获得的信号显著高于纳克级化学发光剂。结论:选用高电压、短时间组合,选择含20%甲醇转移缓冲液和飞克级化学发光剂信号均有助于小分子蛋白免疫印迹检测。 相似文献
158.
Virologica Sinica - The on-going global pandemic of coronavirus disease 2019 (COVID-19) caused by a novel coronavirus called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been... 相似文献
159.
Biochemical entities involved in reactive oxygen species generation by human spermatozoa 总被引:3,自引:0,他引:3
Summary. Spermatozoa were the first cell type suggested to generate reactive oxygen species. However, a lack of standardization in
sperm preparation techniques and the obfuscating impact of contaminating cell types in human ejaculates have made it difficult
to confirm that mammalian germ cells do, in fact, make such reactive metabolites. By identifying, on a molecular level, those
entities involved in reactive oxygen species generation and demonstrating their presence in spermatozoa, the role of redox
chemistry in the control of sperm function can be elucidated. Two major proteins have apparently been identified in this context,
namely, NOX5, a calcium-activated NADPH oxidase, and nitric oxide synthase. Understanding the involvement of these enzymes
in sperm physiology is essential if we are to understand the causes of oxidative stress in the male germ line.
Received May 2, 2002; accepted July 26, 2002; published online May 21, 2003
RID="*"
ID="*" Correspondence and reprints: Discipline of Biological Sciences, University of Newcastle, Callaghan, NSW 2308, Australia. 相似文献
160.
Andre P Bilger S Remy P Bettinger S Vidon DJ 《Biochemical and biophysical research communications》2003,304(4):807-811
Listeria monocytogenes and Listeria innocua are able, under certain conditions, to produce chemiluminescence (CL), which is amplified by luminol. Kinetic studies of CL by L. monocytogenes and L. innocua show a close parallelism between CL and growth curves during the exponential phase, with a maximum of CL reached just before entrance of bacteria into the stationary phase. CL is tightly correlated with the release of oxygen compounds. The reactive oxygen species scavengers tryptophan, mannitol, and tiron, as well as cellobiose and high temperature, were assessed with regard to CL in the two Listeria species. Only tiron strongly reduced the CL emitted by L. monocytogenes and L. innocua. On the other hand, charcoal pretreatment of the growth medium inhibited the CL, whereas ferric citrate strongly increased the CL of L. monocytogenes and L. innocua. These data suggest that iron and superoxide radical are implicated in the CL produced by these bacteria, but this phenomenon is not correlated to virulence. 相似文献