Background Recently, due to the rapid development of proteomic techniques, great advance has been made in many scientific fields. We aimed to use magnetic beads （liquid chip） based matrix-assisted laser desorption/i...Background Recently, due to the rapid development of proteomic techniques, great advance has been made in many scientific fields. We aimed to use magnetic beads （liquid chip） based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） technology to screen distinctive biomarkers for lung adenocarcinoma （adCA）, and to establish the diagnostic protein profiles. Methods Using weak cation exchange magnetic beads （MB-WCX） to isolate and purify low molecular weight proteins from sera of 35 lung adCA, 46 benign lung diseases （BLDs） and 44 healthy individuals. The resulting spectra gained by anchor chip-MALDI-TOF-MS were analyzed by ClinProTools and a pattern recognition genetic algorithm （GA）. Results In the working mass range of 800-10 000 Da, 99 distinctive peaks were resolved in lung adCA versus BLDs, while 101 peaks were resolved in lung adCA versus healthy persons. The profile gained by GA that could distinguish adCA from BLDs was comprised of 4053.88, 4209.57 and 3883.33 Da with sensitivity of 80%, specificity of 93%, while that could separate adCA from healthy control was comprised of 2951.83 Da and 4209.73 Da with sensitivity of 94%, specificity of 95%. The sensitivity provided by carcinoembryonic antigen （CEA） in this experiment was significantly lower than our discriminatory profiles （P 〈0.005）. We further identified a eukaryotic peptide chain release factor GTP-binding subunit （eRF3b） （4209 Da） and a complement C3f （1865 Da） that may serve as candidate biomarkers for lung adCA. Conclusion Magnetic beads based MALDI-TOF-MS technology can rapidly and effectively screen distinctive proteins/polypeptides from sera of lung adCA patients and controls, which has potential value for establishing a new diagnostic method for lung adCA.展开更多
目的:研究不同实验条件下自制裸磁珠对细菌吸附效率,优化吸附条件,为后续裸磁珠的应用研究奠定基础。方法:考察不同的磁珠用量、菌量、孵育温度、孵育时间下磁珠对细菌吸附效率,比较磁珠的保存方法对其吸附率的影响。用磁珠吸附定量细...目的:研究不同实验条件下自制裸磁珠对细菌吸附效率,优化吸附条件,为后续裸磁珠的应用研究奠定基础。方法:考察不同的磁珠用量、菌量、孵育温度、孵育时间下磁珠对细菌吸附效率,比较磁珠的保存方法对其吸附率的影响。用磁珠吸附定量细菌后计数残留菌数,计算其吸附率。结果:磁珠用量与吸附率近似正相关,吸附容量与原始菌量存在对数线性相关。温度影响吸附效率。孵育时间40 m in后吸附率无明显差异,达到平衡。此外,干式和湿式保存的磁珠,对试验细菌的吸附率无明显差异。结论:自制裸磁珠以50 mg(干式)37℃孵育40 m in对高菌量试验菌(>106cfu/m l)有较高的吸附效率(>80%),可望用于样品中细菌的分离富集。展开更多
A high sensitive chemiluminescent magnetic enzyme-linked immunoassay method was established for Escherichia coli O157∶H7 determination.The bacterium antibody was labeled by alkaline phosphatase（ALP） that catalyzed ...A high sensitive chemiluminescent magnetic enzyme-linked immunoassay method was established for Escherichia coli O157∶H7 determination.The bacterium antibody was labeled by alkaline phosphatase（ALP） that catalyzed the decomposing of substrate 3-（2-spiroadamantane）-4-methoxy-4（3-phosphoryloxy）phenyl-1,2-dioxetane（AMPPD） to give the light emission.The sensitivity of the method is 8.5×104 Cell/mL with a linear range of 1.0×105—5.0×107 Cell/mL.The intra- and inter-assay CVs are 14.8% and 20.0% in pork samples, respectively.The correlation coefficient of present and the standard plate counting method is 0.981.The experiments with the spiked samples show that this method has great potential to be applied to（detecting） the concentration of Escherichia coli O157∶H7 in a variety of samples.展开更多
基金This work was supported by grants from the National Natural Science Foundation of China （No. 30570795） and Program for New Century Excellent Talents in University （No. NECT-06-0845） and the Program in Science and Technology of Xi＇an, Shaanxi Province （No. S F08009（1））.Acknowledgement： We are grateful to HU Xiao-hui for the technical guidance.
文摘Background Recently, due to the rapid development of proteomic techniques, great advance has been made in many scientific fields. We aimed to use magnetic beads （liquid chip） based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS） technology to screen distinctive biomarkers for lung adenocarcinoma （adCA）, and to establish the diagnostic protein profiles. Methods Using weak cation exchange magnetic beads （MB-WCX） to isolate and purify low molecular weight proteins from sera of 35 lung adCA, 46 benign lung diseases （BLDs） and 44 healthy individuals. The resulting spectra gained by anchor chip-MALDI-TOF-MS were analyzed by ClinProTools and a pattern recognition genetic algorithm （GA）. Results In the working mass range of 800-10 000 Da, 99 distinctive peaks were resolved in lung adCA versus BLDs, while 101 peaks were resolved in lung adCA versus healthy persons. The profile gained by GA that could distinguish adCA from BLDs was comprised of 4053.88, 4209.57 and 3883.33 Da with sensitivity of 80%, specificity of 93%, while that could separate adCA from healthy control was comprised of 2951.83 Da and 4209.73 Da with sensitivity of 94%, specificity of 95%. The sensitivity provided by carcinoembryonic antigen （CEA） in this experiment was significantly lower than our discriminatory profiles （P 〈0.005）. We further identified a eukaryotic peptide chain release factor GTP-binding subunit （eRF3b） （4209 Da） and a complement C3f （1865 Da） that may serve as candidate biomarkers for lung adCA. Conclusion Magnetic beads based MALDI-TOF-MS technology can rapidly and effectively screen distinctive proteins/polypeptides from sera of lung adCA patients and controls, which has potential value for establishing a new diagnostic method for lung adCA.
基金National Natural Science Foundation of China(30270849),High-Tech Research and Development Program of China (2001AA241211) and Hunan Provincial Natural Science Foundation (04JJ3016)
文摘目的:研究不同实验条件下自制裸磁珠对细菌吸附效率,优化吸附条件,为后续裸磁珠的应用研究奠定基础。方法:考察不同的磁珠用量、菌量、孵育温度、孵育时间下磁珠对细菌吸附效率,比较磁珠的保存方法对其吸附率的影响。用磁珠吸附定量细菌后计数残留菌数,计算其吸附率。结果:磁珠用量与吸附率近似正相关,吸附容量与原始菌量存在对数线性相关。温度影响吸附效率。孵育时间40 m in后吸附率无明显差异,达到平衡。此外,干式和湿式保存的磁珠,对试验细菌的吸附率无明显差异。结论:自制裸磁珠以50 mg(干式)37℃孵育40 m in对高菌量试验菌(>106cfu/m l)有较高的吸附效率(>80%),可望用于样品中细菌的分离富集。
文摘A high sensitive chemiluminescent magnetic enzyme-linked immunoassay method was established for Escherichia coli O157∶H7 determination.The bacterium antibody was labeled by alkaline phosphatase（ALP） that catalyzed the decomposing of substrate 3-（2-spiroadamantane）-4-methoxy-4（3-phosphoryloxy）phenyl-1,2-dioxetane（AMPPD） to give the light emission.The sensitivity of the method is 8.5×104 Cell/mL with a linear range of 1.0×105—5.0×107 Cell/mL.The intra- and inter-assay CVs are 14.8% and 20.0% in pork samples, respectively.The correlation coefficient of present and the standard plate counting method is 0.981.The experiments with the spiked samples show that this method has great potential to be applied to（detecting） the concentration of Escherichia coli O157∶H7 in a variety of samples.
