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Objective: The aim of this study was to establish reproducible two-dimensional electrophoretic assay used for profiling and identification of differentially expressed proteins in human stage I lung adenocarcinoma and paired normal tumor-adjacent tissue. Methods: The proteins from 12 human stage I lung adenocarcinoma tissues and normal tumor-adjacent tissues were separated using isoelectric focusing electrophoresis (the first dimension) and the subsequent homogeneous SDS-polyacrylamide gel electrophoresis (SDS-PAGE) (the second dimension). The differentially expressed proteins were determined with PDQuest image analysis software, and identified using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS) and database searching. Results: The well-reproducible 2-DE gel patterns of human stage I lung adenocarcinoma and normal tumor-adjacent tissues were profiled and 26 differentially expressed proteins uncovered. Nine of these 26 protein spots were cut out from the preparation gels and determined with MALDI-TOF-MS. Searching against the protein database, four candidate proteins were identified. They were 60S acidic ribosomal protein P2, Cathepsin B1, Apolipoprotein A-I precursor, and La 4.1 protein. Conclusion: In this study, high reproducible 2-DE gel protein images of human stage I lung adenocarcinoma and paired normal tumor-adjacent tissues were achieved successfully, and 4 differentially expressed proteins were revealed. These data will be helpful for screen of early biomarker and study of molecular mechanisms of human lung adenocarcinoma.  相似文献   
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目的类风湿关节炎(Rheumatoid arthritis,RA)是一个多基因多因素参与的病理过程。实验中通过建立与RA发病机制相似的胶原诱导性关节炎(Collagen-induced arthritis,CIA)大鼠动物模型,运用蛋白质组技术对正常大鼠和CIA大鼠模型不同时间点滑膜组织的蛋白质点进行比较分析,为鉴定CIA大鼠滑膜病变相关蛋白质及研究RA发病机制奠定基础。方法用牛Ⅱ型胶原和完全福氏佐剂建立CIA大鼠模型,采用一步抽提法抽提滑膜蛋白质,运用固相pH梯度双向凝胶电泳分离各组大鼠滑膜组织的总蛋白质,用PDquest软件分析图谱,比较差异蛋白质,应用基质辅助激光解吸电离飞行时间质谱(Matrix-assisted laser desorption/ionization time-of-flightmass spectrometry,MALDI-TOF-MS)得到相应肽质指纹图谱,用Mascot查询软件搜索数据库,鉴定部分差异蛋白质。结果成功建立了CIA大鼠模型,获得分辨率较高、重复性较好的大鼠滑膜组织双向电泳凝胶图谱。正常组与25、35和45天模型组大鼠滑膜组织凝胶图谱的平均蛋白质点数分别为1070±41、1049±22、1079±44和1088±39。在4个组均有表达差异的蛋白质点中随机取20个点进行肽质指纹图分析,鉴定了部分与细胞代谢、信号转导及结构相关的差异表达蛋白质。结论建立了分辨率较高且重复性较好的正常大鼠与CIA大鼠不同时间点滑膜组织的双向凝胶电泳图谱,鉴定了一些与CIA大鼠滑膜病变相关的差异表达蛋白质,为识别RA病变相关蛋白质及推断RA病变过程奠定基础。  相似文献   
4.
目的应用源后衰变(PSD)技术结合数据库检索鉴定二维蛋白质电泳(2DE)胶上的蛋白质斑点。方法 用已知多肽(ACTH)18~39肽段和TPA被胰酶降解后的1个肽段建立了PSD-MALDI-TOF-MS方法。结果应用已建立的PSD-MALDI-TOF-MS法分别将2DE分离后胶上的2个未知蛋白质斑点鉴定为40S核糖体蛋白S12和dnaK抑制蛋白。结论PSD技术在蛋白质组学研究中有较大的应用前景。  相似文献   
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应用飞行时间质谱仪快速鉴定细菌的初步研究   总被引:5,自引:1,他引:5  
孙宗科  张伟  陈西平 《卫生研究》2004,33(5):552-554
目的 研究基质辅助激光解析电离飞行时间质谱对细菌快速鉴定的影响因素。方法 应用 8种细菌 ,比较了不同培养基 (哥伦比亚血琼脂、伊红美兰琼脂、普通营养琼脂 )及培养时间对细菌质谱图的影响。结果 不同的培养基及培养时间会对细菌质谱图产生影响。结论 选择合适的培养基及培养时间可以提高细菌检测的准确率  相似文献   
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目的:利用蛋白质组学方法,识别并鉴定幽门螺杆菌(Helicobacter pylori,H.pylori)处理HepG2细胞后差异表达的蛋白质,为进一步探讨幽门螺杆菌对肝细胞的病理作用机制奠定基础。方法:运用固相pH梯度双向凝胶电泳技术分离H.pylori处理前后HepG2细胞的总蛋白质,用图象分析软件比较分析,以识别差异表达的蛋白质;应用质谱仪(mass spectrometry)得到相应的肽质指纹图谱(peptide mass fingerprint,PMF),然后搜索数据库鉴定差异蛋白质。结果:鉴定出12种差异表达蛋白质.这些蛋白质包括整合素β-1、蛋白激酶C—α、PINCH蛋白、Ras相关蛋白Rab-37、LIM同源盒蛋白Lhx1、HLAⅠ类抗原、血管抑制素和金属蛋白酶抑制因子2等。这些差异蛋白质涉及基因表达调控、细胞免疫、细胞生长和信号传导等众多关键事件。结论:H.pylori处理前后HepG2的蛋白质组具有差异,这些差异表达的蛋白质可能参与了H.pylori对肝细胞的病理作用过程,这种蛋白质组的差异分析有助于进一步研究H.pylori与人类肝脏疾病的关系。  相似文献   
7.
Beta defensins (BD) are cysteine rich, cationic antimicrobial peptides (AMP) produced mainly by epithelial and myeloid cells such as neutrophils. In birds, the neutrophil equivalent heterophils produce avian beta defensins (AvBD) of which AvBD2 is the major isoform. Heterophils recognize pathogens or their derived products through a series of pattern recognition receptors called toll-like receptors (TLR) leading to their antimicrobial activities. This work is the first report of TLR modulation of AvBD2 expression in chickens. To measure the effect of TLR activation on AvBD2 production, the heterophils were cultured with different TLR agonists for 6 h. Modulation of AvBD2 levels by TLR activation was measured using direct MALDI mass spectrometry without stable isotopic labeling or chromatographic separation. Chemical modification of the conditioned media was performed using reduction/alkylation with dithiothreitol/iodoacetamide to distinguish TLR treated AvBD2 (reduced/alkylated) from controls (non-reduced). Changes in corrected ion intensity ratios were assumed to reflect AvBD2 modulation in heterophils upon activation with different TLR agonists. In general, TLR agonists increased AvBD2 production with LPS showing the greatest induction and CpG-ODN showing little or no effect. These data show that the direct MALDI-MS coupled with reduction/alkylation may provide a rapid relative quantitative approach to the measurement of agonist-induced differential expression of AvBD2.  相似文献   
8.
目的:建立二氧化硅诱导早期肺损伤大鼠肺组织的二维凝胶电泳图谱,筛选在此过程中起关键作用的靶 蛋白分子并进行验证。方法:制作二氧化硅诱导大鼠早期肺损伤模型(实验组),通过HE染色观察肺部形态变化,用 双向凝胶电泳法建立二维凝胶图谱,用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)分析鉴定差异表达蛋白 分子,用Western印迹验证差异表达蛋白分子在肺组织中的表达。结果:成功制作二氧化硅早期肺损伤模型,建立实 验组及对照组肺组织二维凝胶电泳图谱,二者蛋白表达及分布存在差异,发现差异点40个,选取重复性好,在凝胶 上位置和表达适中的共20个进行MALDI-TOF-MS鉴定及数据库搜索并筛选,鉴定出差异蛋白13种,包括α晶状体球蛋 白B、间隙蛋白I、肥大细胞蛋白酶等,进一步用Western印迹证实实验组α晶状体球蛋白B表达明显增加,与蛋白质组 学结果一致。结论:α晶状体球蛋白B在早期矽肺组织中表达明显升高,提示其可能在矽肺的发生发展中起关键作用。  相似文献   
9.
Obligate anaerobes exist as resident flora in various sites in humans, but they are also emphasized as endogenous causative microorganism of infections. We performed surveillance to understand the trend of drug susceptibility in obligate anaerobic bacteria in the Kinki area of Japan. In the experiment, we used 156 obligate anaerobe isolates collected from 13 institutions that participated in the Study of Bacterial Resistance Kinki Region of Japan. MALDI Biotyper was used to identify the collected strains, and among the 156 test strains, those that could be identified with an accuracy of Score Value 2.0 or more included 6 genera, 30 species, and 144 strains (Bacteroides spp. 77 strains, Parabacteroides sp. 2 strains, Prevotella spp. 29 strains, Fusobacterium spp. 14 strains, Porphyromonas spp. 2 strains, and Clostridioides difficile 20 strains), and they were assigned as subject strains for drug susceptibility testing. The drug susceptibility test was carried out by broth microdilution method using Kyokuto Opt Panel MP ANA (Kyokuto Pharmaceutical Industrial Co., Ltd., Tokyo, Japan) and judged according to CLSI criteria. As a result, Bacteroides and Parabacteroides species showed good sensitivities to tazobactam-piperacillin, imipenem, metronidazole and chloramphenicol, and low sensitivities to ampicillin, cefoperazone and vancomycin. Prevotella species showed good sensitivities to sulbactam-ampicillin, tazobactam-piperacillin, cefmetazole, imipenem, doripenem and metronidazole. Susceptibility rates to other drugs were slightly different depending on the bacterial species. Both Fusobacterium spp. and Porphyromonas spp. showed high sensitivities to many drugs. C. difficile was highly sensitive to vancomycin and metronidazole, having MIC90s of 0.5 μg/mL and ≤2 μg/mL, respectively.  相似文献   
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Endometriosis is associated with an increased risk of ovarian cancer. Few studies have also shown increased risk of breast cancer. BRCA1/2 mutations are linked to an increased risk of breast and ovarian cancers but their relation to endometriosis is unknown.  相似文献   
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