A comprehensive approach to the quantitative determination of sodium-diphacinone in human andrabbits organ tissues samples based on solid-phase extraction and derivative spectrophotometry hasbeen developed. This procedure, using acetonitrile to precipitate protein of tissues and GDX403(polymeric resine made in China) as absorbent in solid-phase extraction, was sufficientIy simple,rapid and cheaper. Results of this method was also reliable- Recoveries of sodium-diphacinone fromspiked tissues were around 70% at levels from 5 to 40pg/g. The detection limits of about 1 ?g/g forsodium-diphacinone could be achieved.

A method was developed to assay α-Hydroxyltriazolam and α-Hydroxyalprazolam,　which are the major metabolites of triazolam and alprazolam respectively,in human urine.　After addition of 2-hydroxyflurazepam　(interal standard) and hydrolysis with β-glucuronidase, the hydroxy-metabolites were extracted with hexane-dichloromethane (1∶1) at pH　10.8, then were derivated with (BSTFA). The analysis was performed on a HP-5 capillary column with electron-capture detector.The detection limits of analysis in urine were about 1μg/L.The method was successfully applied to urine specimens collected from healthy human volunteers who ingested 0.5 mg of triazolam or 0.8 mg alprazolam. The method was enough sensitive to assay urine specimen excreted at 24 h by volunteers after taking the medicine.

Abstract: Objective　To genotype and analyze whole genomic features of Coxsackievirus B3 (CVB3) isolated in Tianjin, to improve evolution information of CVB3 virus in Tianjin, and to provide basis for surveillance and early warning of related diseases. Methods　Viral RNA was extracted from five CVB3 strains isolated in Tianjin, whole genome sequence of the virus was amplified by RT-PCR and sequenced by next-generation sequencing method, and phylogenetic and recombinant analysis were carried out. Results　The open reading frame 1(ORF) of the five CVB3 strains contained 6 555 nucleotides and encoded 2 185 amino acids, and ORF2 was composed of sequences encoding 68 amino acids. The nucleotide sequence similarity ranged from 78.3%-100%, and the amino acid sequence similarity ranged from 95.7%-100%. Compared with the CVB3 prototype strain, the nucleotide sequence similarity of the five viruses was between 78.2%-79.1%, and the similarity of amino acid sequences was 94.9%-95.3%. All five viruses exhibited a T151A mutation on the VP2 protein. Additionally, the encephalitis isolate showed a K158E mutation on the VP2 protein, while one of the sewage isolates had a C234T mutation in 5' noncoding region. The five strains belonged to two different genotypes, among which the encephalitis isolate in 2016 belonged to the D genotype, while the sewage isolates in 2021 belonged to the E genotype. This is also the first report of E genotype CVB3 in northern China. The CVB3 strain may have recombinant events in non-structural protein regions, in which encephalitis isolate may recombine with a Coxsackievirus B5 (CVB5) strain, while sewage isolates may have recombinant events with a strain of ECHO virus 18 (E18). Conclusions　The CVB3 isolates in Tianjin belong to D and E genotypes, and recombination events may exist in non-structural protein region of the viral genome. The results of CVB3 virus genome analysis in sewage suggests presence of CVB3 infection in the population of Tianjin, and its epidemic dominant genotype may have changed.

OBJECTIVETo evaluate the effects of polymorphisms in XRCC1 and APE1 genes on vinyl chloride (VC)-induced chromosomal damage in peripheral lymphocytes.

METHODSIn this study, 317 workers occupationally exposed to VC were recruited from a factory in Shandong Province, China. The micronucleus (MN) frequency in peripheral lymphocytes was used as an indicator of chromosomal damage. Polymerase chain reaction-restriction fragment length polymorphism and created restriction site combined with restriction fragment length polymorphism were used to determine the five single nucleotide polymorphisms in XRCC1 and APE1 genes in the base excision repair pathway. The association of chromosomal damage with these polymorphisms and the haplotype of XRCC1 was analyzed using Poisson regression and PHASE 2.0.2.

RESULTSIt was found that among the VC-exposed workers, individuals with XRCC1 polymorphisms (-77C/T, Arg194Trp, Arg280His, and Arg399Gln) had a significantly higher MN frequency than those with homozygous wild-type genotypes, with frequency ratios (FR) as follows, respectively: FR = 1.21, 95%CI: 1.05∼1.39 (P < 0.05); FR = 1.14, 95%CI: 1.00∼1.38 (P < 0.05); FR = 1.26, 95%CI: 1.11∼1.44 (P < 0.05); FR = 1.23, 95%CI: 1.08∼1.46 (P < 0.05). APE1 Asp148Glu was found of no significant relationship with MN frequency. Haplotype analysis of XRCC1 demonstrated that the MN frequencies in subjects with CTAA/CTAA and CCAA/CTAA were significantly higher than that in those with TCGG/TCGG (FR = 1.19, 95%CI: 1.02∼1.32, P < 0.05; FR = 1.41, 95%CI: 1.02∼1.87, P < 0.05). Furthermore, association was found between accumulated exposure to VC and XRCC1 polymorphisms (-77C/T, Arg194Trp, Arg280His, and Arg399Gln) after adjustment for age, sex, drinking, and smoking.

CONCLUSIONVC can induce chromosomal damage even when the exposure level is lower than the national occupational health standard of China (PC-TWA: 10 mg/m(3)); the polymorphisms in XRCC1 and APE1 are associated with chromosomal damage induced by VC.

Adult ; DNA-(Apurinic or Apyrimidinic Site) Lyase ; genetics ; DNA-Binding Proteins ; genetics ; Female ; Haplotypes ; Humans ; Male ; Micronuclei, Chromosome-Defective ; Middle Aged ; Occupational Exposure ; adverse effects ; Polymorphism, Restriction Fragment Length ; Vinyl Chloride ; poisoning ; X-ray Repair Cross Complementing Protein 1 ; Young Adult

Objective:To analyze the whole genome traceability and variation analysis of SARS-CoV-2 in local COVID-19 outbreaks in Binhai New Area, Tianjin.Methods:The whole-genome high-throughput sequencing was performed on throat swab samples collected from one local asymptomatic infected person and five confirmed cases of COVID-19 in Binhai New Area of Tianjin from November 7 to December 5, 2020. The sequencing data were assembled by De novo. MAFFT v7.0 multiple sequence alignment program and MEGA X software were used to compare the above data and construct phylogenetic tree (Neighbor-joining method).Results:The genetic similarity between the sequences of 6 SARS-CoV-2 strains and Wuhan reference sequence (Wuhan-Hu-1) was greater than 99.9%. Two of six strains were genetically identical, conform to the L-Lineage European Branch Ⅱ.1(America Branch)/B.1; The other four strains had the same genes and were in line with the characteristics of L-Lineage European Branch Ⅰ/B.1.1.These six strains belonged to different evolutionary branches and two different transmission chains. There were 18 nucleotide mutation sites in sequences of six SARS-CoV-2 strains, eight of which were synonymous mutation sites, nine of which were missense mutation sites, resulting in nine amino acid mutation sites, and important mutation sites of RDRP-P323L and S-D614G were found in all of the six samples.Conclusions:In this study, there were two COVID-19 outbreaks in Binhai New Area of Tianjin, and the sequences of six SARS-CoV-2 strains belonged to different evolutionary branches and two different transmission chains. It might come from porters′ contact with imported cold chain items contaminated with SARS-CoV-2 from different sources. All the sequences of six SARS-CoV-2 strains had P323L and D614G mutations, which indicated that the virus mutation and transmission ability were stronger. The surveillance of important employees of the cold chain in Tianjin and local and imported cases should be continuously strengthened.

Objective:To study the characteristics and evolution of the whole genome sequence of an imported Chikungunya virus (CHIKV) case in Tianjin, China, and to provide a scientific basis for the surveillance and control of CHIKV.Methods:The serum specimen of CHIKV was collected at Tianjin Second People's Hospital, on November 4th, 2019, and the viral RNA was extracted. Eleven overlapping primers were used to amplify the complete genome of CHIKV by RT-PCR. The amplification products were then subjected to next generation sequencing (NGS) using Illumina Miniseq platform.Results:The complete genome sequence of the Tianjin CHIKV obtained had similarities ranging from 92.72% to 99.86% with other Chinese isolates. Phylogenetic analysis indicated that the Tianjin CHIKV belonged to the Indian Ocean Lineage (IOL), East/Central/South African (ECSA) cluster, consistent with most strains from China. The Tianjin CHIKV is most similar (99.74%) to a Pakistan strain. Compared with the reference strain S27, 37 non-structural and 28 structural protein amino acid substitutions had been detected in Tianjin CHIKV genome, including two key site mutations, E1-D284E and E2-I211T, in accordance with other strains in the ECSA cluster. Besides, Tianjin CHIKV possessed two point virulent residues at position 12 and 82 in E2, and also a nsP3-R524Opal nonsense mutation.Conclusions:Tianjin CHIKV showed stronger virulence and greater transmissibility in Aedes albopictus. Therefore, the surveillance and monitoring of CHIKV in China should be strengthened.