ABSTRACT
A novel suspension array technology was established for the detection of three kinds of veterinary drug residues: chloramphenicol, clenbuterol and 17-β-estradiol. The three conjugates in which veterinary drugs coupled with BSA were immobilized on the solid carrier of the suspension microarray-polystyrene fluorescent microspheres/beads as detective probes. Indirect competitive technology was employed. Competitive reactions between the veterinary drugs in the aqueous phase and the veterinary drugs-BSA conjugates on the beads for coupling with their complimentary specific biotinylated monoclonal antibodies were carried out. And then, straptavidin-phycoerythrin was added for coupling and the fluorescent signals were captured. Afterwards the detective standard curves were plotted. The regular ELISA standard curves of the three veterinary drugs were also plotted. Comparison between suspension array and regular enzymE-linked immunosorbent assay(ELISA) was in the respects of the detective technology, the detection limits, the detective ranges, the samples detection and the multi-analysis. Suspension array technology is distinct advantageous except for specificity. There was well consistent performance between the two methods. The high-throughput suspension array provides a novel method for multi-analysis of veterinary drugs with simple operation, sensitive, rapid and low costing.
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Objective To detect the intestinal pathogenic bacteria quickly and accurately from water. Methods An experimental procedure is set up using the gene chip technology to detect and identify common intestinal pathogenic bacteria from water. Target gene was amplified and hybridized with prepared gene chip.Results 143 strains of bacteria in pure culture belong to 9 genera are successfully discriminated under comparatively same condition and a series of specific hybridization maps corresponding to each kinds of bacteria are obtained.Conclusions Salmonella spp., Shigella spp., Staphylococcus spp., Proteus spp., Escherichia coli, Yersinia enterocolitica, Listeria monocytogenes and Vibrio parahaemolyticus are detected and identified by the technology of gene chip. The accuracy, range, and discriminatory power of the assay can be continually improved by adding further oligonueleotides to the arrays without significantly increasing complexity or cost.
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Objective The genotoxicty and its molecular mechanism of environmental tobacco smoke (ETS) were discussed through the oxidative DNA damage induced by environmental tobacco side_stream smoke(ETSS). Methods DNA adduct 8_hydroxydeoxyguanosine (8_OHdG) was used as a biomarker of oxidative DNA damage. The level of 8_OHdG in DNA exposed to ETSS was detected by HPLC_EC.On the molecular biological level,the biological oxidative ability of ETSS on DNA molecule was studied.Organic and inorganic components in ETSS were analyzed by GC_MS and AAS respectively. Results Particles and VOCs in ETSS could directly induce oxidative DNA damage and form 8_OHdG.It was found that there were 123 and 84 kinds of organic compounds in particles and volatile organic compounds of tobacco smoke side stream,and 7 kinds of inorganic compounds in ETSS.Some components especially quinones and polyphenols in ETS,could produce free radicals in vitro by the auto_oxidation without any biological activity systems,and with the catalytic reaction of metals,the DNA aduct 8_OHdG was produced. Conclusion It was proved that ETS had biological oxidative ability on DNA and expressed direct genotoxicity.8_OHdG was a fine biomarker of effect of oxidative DNA damage.
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Objective To amplify and sequence the distinctive norB gene of Nitrobacterium. Methods The norB gene was amplified by PCR and was cloned into T-vector and then transformed into E.coli JM109. After white-and-blue selection, positive colonies were sequenced with T7 sequencing primers by Takara Company. Spliced with Vector NTI Suite software, the homologous analysis of sequences were conducted in Genbank through Internet. Results The results showed that all of norB genes obtained from the nitrite-oxidizing bacteria were homologous with the norB gene of Nitrobacterium hamburgensis in Genbank. The homology ranged from 96% to 98%, and there were no frameshift mutations, which guaranteed the correct ORF. Conclusion The obtained genes are norB genes indeed.
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The meaning of proteome research,definition and technique system of proteome are summarized in this article.In the post-genome age,research on proteomics has become more and more important,because changes in proteins which are expressed by genes are the direct causes of life function disorders.Proteome is the entire complement of proteins expressed by a kind of cell,tissue or organism.Proteomic techniques mainly include two-dimensional electrophoresis,mass spectrometry and bioinformatics.In addition,the application of proteome techniques published home and abroad in the field of environmental health in recent years has also reviewed in this paper.
ABSTRACT
Objective To screen and seperate nitrobacteria that could be used to treat nitrogenous compound pollution.Methods Autotrophic nitrite-oxidizing microorganisms were screened by enrichment culture from soil.After morphological and biological detection,primers were designed to detect the distinctive gene norB of nitrobacteria.The PCR production was se-quenced,and the homology was identified according to the sequence in Genbank.Results One strain of bacterium was screened that could oxidize nitrite.This bacterium was small,light-yellow bacilli.The expected-size DNA fragments could be amplicated by PCR.The sequence of a PCR production was blasted in Genbank and showed99%consistent with norB gene of N hamburgensis.Conclusion It was preliminarily confirmed that the microorganism screened in this study might be nitrobac-terium.