ABSTRACT
From the basic research, key technologies and product development and typical application demonstration, this paper expounds the latest scientific and technological progress made in China in the prevention and control of emergent pathogens and infectious diseases. The future development of science and technology is also prospected.
ABSTRACT
This article describes the developing process of China’s pathogenic microorganism laboratory construction through a fair summary of the key points and events involving the issues of "Pathogenic Microbiology Laboratory Biosafety Management Regulations" , "National High Level Biosafety Laboratory System Construction Plan "and "High Level Biosafety Laboratory System Construction Plan" (2016-2025) " , the research and development of Domestic Mobile Biological Safety Level-3 Lab, the establishment and operation of Wuhan National Biosafety Laboratory and the release of other key technology and equipment development.
ABSTRACT
Objective Beagle dogs are commonly used animal for drug safety evaluation .As the necessary parameters , blood biochemical indicators are detected in acute or chronic toxicity tests .This study aims at assessing the influence of different preservation conditions and different preservation time on blood biochemical indicators to ensure the reliability of test results of long-term toxicity assessment .Methods Six Beagle dogs (3 males and 3 females) were used in this study .After collection and preparation of serum samples , biochemical indicators were detected after preservation in refrigerator at 2-8℃for 1, 2, 5, 8, and 12 hours;after preservation in ice transportation boxes at 2-10℃for 2, 5, and 8 hours;and after preservation in refrigerator at -20℃ for 1, 3, and 5 days.The biochemical indicators included alanine aminotransferase ( ALT ) , aspartate aminotransferase ( AST ) and alkaline phosphatase ( ALP ) , total protein ( TP ) , albumin (propagated), urea, creatinine (CREA), glucose (GLU), total cholesterol (TCHO), total bilirubin (TBIL), creatine kinase ( CK ) , gamma pancreatic acyl transferase ( GGT ) , calcium ( CA ) , lactate dehydrogenase ( LDH ) , phosphorus ( P) , high-density lipoprotein cholesterol ( HDL-C) , low density lipoprotein cholesterol ( LDL-C) , triglyceride ( TG) , sodium ( Na+) , potassium ( K+) and chloride ( Cl -) .Results Compared with the results of samples preserved for 1 hour, the LDL-C result of that preserved in refrigerator at -20℃for 5 days was significantly increased (P0.05 ) , and the coefficient of variation of LDH was 41%.Conclusions According to the test results of blood biochemical indicators in the Beagle dogs detected after different preservation conditions and different preservation time in this study , detection test should be done within 1 hour, if not, detection should be done within 12 hours for the samples preserved at 2~8℃, or within 3 days for the sample preserved at -20℃.For transportation of serum samples , the serum samples should be placed in the ice box at 2~10℃, and detection test should be done within 8 hours .
ABSTRACT
A simple analytical method by means of on-line solid phase extraction followed liquid chromatography-tandem mass spectrometry ( SPE-LC-MS/MS) was developed for the simultaneous quantitation of 4 endocrine disruptors ( triclosan, triclocarban, bisphenol A and nonylphenol) in dairy products. Infant formula and milk samples were dissolved in acetic acid buffer and hydrolyzed by β-glucuronidase/arylsulfatase. Acetonitrile was used as the extract. Then, the mixture was freeze-centrifuged for 10 min and the supernatant was diluted with water, and analyzed via on-line SPE-LC-MS/MS. The sample extracts were concentrated by an Xbridge C8 cartridge and separated on a BEH C18 column with a gradient mobile phase of methanol and water; then analyzed by triple quadrupole mass spectrometry. Mass acquisition was conducted under negative electrospray ionization mode. Quantification was performed by isotopic internal standard calibration. Acceptable linearity (R2>0. 99) was achieved over the range of 0. 005-5. 0 μg/L, with limits of quantification of 0. 03-1. 0μg/kg. Average recoveries of four target compounds (spiked at three concentration levels) ranged from 80. 2%-106. 7%,with relative standard deviation less than 15%. Due to its rapidity, simplicity, and high sensitivity, the method is suitable for the analysis of endocrine disruptors in dairy products. It has been applied in the analysis of raw milk and milk products collected in Beijing. As a result, nonylphenol was found with a high detectable frequency.