Li X.,Shanghai University |
Qiu L.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China |
Li Y.,Eastern Hepatobiliary Surgery Hospital |
Chen X.,Shanghai University |
And 2 more authors.
Biomedical Chromatography | Year: 2015
This study was designed to develop a high-performance liquid chromatographic-electrospray ionization-mass spectrometry (HPLC-ESI-MS) method for quantitative determination of residual surfactant linear alkylbenzene sulfonate (LAS) compounds on pharmaceutical rubber stoppers. An HPLC-ESI-MS method was developed for separation and determination of five LAS homologs (C10-C14) under gradient conditions using methanol and ammonium acetate as mobile phases. Hemolysis activity of residual LAS compounds was analyzed by spectrophotometry. Expression of interleukin (IL)-6 and tumor necrosis factor (TNF)-α in human umbilical vein endothelial cells (HUVECs) after LAS compound treatment was examined by enzyme-linked sorbent assay. LAS compounds were well separated and determined by the established gradient conditions. The linear range was 0.05-8 μg/mL with correlation coefficients ≥0.997. Recoveries were from 73 to 134% and the relative standard deviation was <13.7%. There was a correlation between hemolysis rate and LAS compounds concentration when it was ≥0.8 μg/cm2. LAS compounds decreased the viability of HUVECs and promoted the production of IL-6 and TNF-α. The developed analytical method was successful for quantitative determination of residual LAS compounds on pharmaceutical rubber stoppers and it is important to monitor and control the amount of LAS compounds on rubber stoppers. © 2015 John Wiley & Sons, Ltd.
Zhang X.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China |
Zou Q.,Nanjing Southeast University |
Zhou Z.,Nanjing Southeast University |
Wu L.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China
Lecture Notes in Electrical Engineering | Year: 2011
In this paper, the isolation and the voltage division factor changes of AMN are studied when AMN is grounded via various ground wires of different impedances, which is to simulate impacts brought by poor ground conditions on in-site test results of EUT. The result shows the isolation and the voltage division factor vary with changes of frequency and the length of the ground wire for AMN. In addition, the impedance of the ground wire will seriously affect the repeatability and the accuracy of the test results. © 2011 Springer-Verlag Berlin Heidelberg.
Fang X.,University of Veterinary and Animal Sciences |
Zhang M.,University of Veterinary and Animal Sciences |
Li S.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China |
Du C.,University of Veterinary and Animal Sciences |
And 4 more authors.
Journal of Microbiology and Biotechnology | Year: 2010
The limited information on differential gene expression in the different serotypes of Actinobacillus pleuropneumoniae has significantly hampered the research on the pathogenic mechanisms of this organism and the development of multivalent vaccines against A. pleuropneumoniae infection. To compare the gene expressions in the A. pleuropneumoniae strains CVCC259 (serotype 1) and CVCC261 (serotype 3), we screened the differentially expressed genes in the two strains by performing representational difference analysis (RDA). Northern blot analyses were used to confirm the results of RDA. We identified 22 differentially expressed genes in the CVCC259 strain and 20 differentially expressed genes in the CVCC261 strain, and these genes were classified into 11 groups: (1) genes encoding APX toxins; (2) genes encoding transferrin-binding protein; (3) genes involved in lipopolysaccharide (LPS) biosynthesis; (4) genes encoding autotransporter adhesin; (5) genes involved in metabolism; (6) genes involved in the ATP-binding cassette (ABC) transporter system; (7) genes encoding molecular chaperones; (8) genes involved in bacterial transcription and nucleic acid metabolism; (9) a gene encoding protease; (10) genes encoding lipoprotein/membrane protein; and (11) genes encoding various hypothetical proteins. This is the first report on the systematic application of RDA for the analysis of differential gene expression in A. pleuropneumoniae serotypes 1 and 3. The determination of these differentially expressed genes will serve as an indicator for future research on the pathogenic mechanisms of A. pleuropneumoniae and the development of a multivalent vaccine against A. pleuropneumoniae infection. © The Korean Society for Microbiology and Biotechnology.
Deng X.-J.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China |
Yang H.-Q.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China |
Li J.-Z.,Agilent Technologies |
Song Y.,Agilent Technologies |
And 4 more authors.
Journal of Liquid Chromatography and Related Technologies | Year: 2011
A high-throughput and robust method for analyzing multiclass residues of veterinary drugs in meat, milk, and egg by ultra-high performance liquid chromatography (UHPLC)-quadrupole time-of-flight mass spectrometry (QTOF) was established. The method successfully applied to the screening, quantification, and confirmation of 105 compounds from 9 different classes of drugs, including beta-agonists, benzimidazoles, corticoides, triphenylmethane, nitromidazoles, quinolones, sulfonamides, tetracylines, and benzodiazepams. The samples are extracted by a single extraction using acetonitrile containing 0.1% formic acid, followed by an easy solid phase extraction (SPE) clean-up on HLB column and finally analyzed by LC/MS QTOF MS. The separation was achieved within 30 min at the optimized chromatographic conditions. More than 92% compounds in this study can be reliably identified based on accurate mass measurement (within the 3 ppm mass error) at the 5 lg/kg concentration levels in the complex food matrix with further MS/MS confirmation. Our study demonstrated a reliable, high-efficient and high-sensitive strategy for the fast and high throughput screening of multiclass of veterinary drugs in foodstuffs of animal origin. Copyright © Taylor & Francis Group, LLC.
Zhao Y.,Shanghai Normal University |
Yao Y.,Shanghai Normal University |
Xiao M.,Shanghai Normal University |
Chen Y.,Shanghai Normal University |
And 5 more authors.
Food Control | Year: 2013
In order to ensure the safety of infant formula powder in China, a rapid and sensitive detection method for food-borne bacteria is urgently needed. We have developed a reliable immunoassay based on nuclear magnetic resonance for the specific detection of Enterobacter sakazakii in dairy samples with biofunctionalized magnetic nanoparticles. This method is able to detect Cronobacter sakazakii in milk powder and cheese samples at 1.1 to 11MPN using the most-probable-number (MPN) assay, within an incubation period of less than 2h. Longer incubation time (>4h) or higher pH (>7) will decrease the sensitivity of this method. This method does not fit for the detection of bacteria at higher concentrations (>1100MPN). This method has great potential to becomea useful tool for the rapid detection of bacterial contaminations in food, environmental and agricultural samples. © 2013 Elsevier Ltd.
Li X.,Shanghai Normal University |
Chen Y.,Shanghai Normal University |
Zhang Z.,Shanghai Normal University |
Han W.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China |
And 5 more authors.
Journal of Chinese Institute of Food Science and Technology | Year: 2013
This paper reported a rapid detection method of Salmonella using low field nuclear magnetic resonance (NMR). The Fe3O4 magnetic nanoparticles were coated with silica to empower the nanoparticles with high dispersion and broad compatibility to biomacromolecules. The magnetic beads were modified with amino silane, which could immobilize antibody. The immune magnetic beads specifically attached to the surface of Salmonella in the enrichment. Nuclear magnetic resonance was used to obtain the value of ΔT2 to determine microorganism polluting condition. In this study, five different bacteria strains (E. coil O157, S. typhimurium, S. flexneri, S. aureus, and V. parahemolyticus) were used as control to test the specificity of this method, which performanced high specificity. Moreover, the reaction conditions were optimized in the study. The results indicated that the optimal concentration of magnetic beads was 0.14 mg/mL and the minimum level of this method was 103 cfu/mL.
Deng X.-J.,Shanghai Entry Exit Inspection and Quarantine Bureau of The Peoples Republic of China |
Guo D.-H.,Shanghai Entry Exit Inspection and Quarantine Bureau of The Peoples Republic of China |
Zhao S.-Z.,Shanghai Entry Exit Inspection and Quarantine Bureau of The Peoples Republic of China |
Han L.,Shanghai Entry Exit Inspection and Quarantine Bureau of The Peoples Republic of China |
And 4 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2010
Utilizing a solid phase extraction column (MCT) containing mixed hydrophilic functional gel and cation exchange sorbent, a sensitive and rapid HPLC-MS/MS method for simultaneously determining the residues of melamine (MEL) and cyanuric acid (CYA) in human foodstuffs was developed. MEL and CYA in egg, pork, liver, kidney and pork, shrimp, sausage casing, honey, soybean milk, soybean powder and dairy product were extracted using acetonitrile/water, defatted with hexane and isolated using MCT solid phase extraction column. The residues were separated upon a hydrophilic interaction liquid chromatography (HILIC) column and analyzed by electrospray ionization under negative-positive switched mode on a triplequadrupole mass spectrometry. The selected reaction monitoring was performed on [M+H] + of m/z 127.9 to provide the transition of 127>85 and 127>68 (MEL) while the [M-H] - of m/z 127.1 was selected as the precursor ion for CYA resulting in product ions m/z 85 and 42. Isotope labeled internal standard ( 15N 3-MEL and 13C 3-CYA) and matrix-matched calibration were both used to observe the recovery to be 70.0-129.6% and 70.0-128.9% with RSD of 1.4-23.3% and 1.5-21.7% for MEL and CYA, respectively (n=6). All the LODs and LOQs of MEL and CYA were less than 39.4 and 99.1μgkg -1, respectively, in 18 matrices, which were sensitive enough for quantitative analysis. This method has been proven effective in simultaneous determination of melamine and cyanuric acid when inspecting unknown and positive samples. © 2010 Elsevier B.V.
Li M.,Donghua University |
Zhang Y.-L.,Donghua University |
Du Z.-X.,Donghua University |
Tang X.-Z.,Shanghai Entry Exit Inspection and Quarantine Bureau of the Peoples Republic of China
International Conference on Internet Technology and Applications, ITAP 2010 - Proceedings | Year: 2010
Based on Dabholkar's service quality model about retailing, evaluation model of outlets' service quality was established. Using Structural Equation Model (SEM), after data processing by data analysis software SPSS13.0 and model analysis software AMOS7.0, the rationality and applicability of the model was good to further analyzed. The model of Physical Aspects, Reliability, Personal Interaction, Problem Solving, Policy, which are five dimensions in the model affecting service quality, had been proved. Ultimately, corresponding marketing advices were put forward for outlets to develop their service quality. It is meaningful for outlets in China to improve their operating level. ©2010 IEEE.