Epidemiological and etiological characteristics of Vibrio parahaemolyticus strains causing foodborne disease outbreaks in Guangdong Province from 2017 to 2020 / 中华预防医学杂志

Objective: To study the epidemiological and pathogenic characteristics of Vibrio parahaemolyticus isolated from outbreaks cases in Guangdong Province, 2017-2020. Methods: Epidemiological characteristics of 87 outbreak events caused by Vibrio parahaemolyticus were analyzed. Strains were serotyped, and then analyzed by pulsed-field gel electrophoresis (PFGE). Results: The food-borne disease outbreak caused by Vibrio parahaemolyticus was found in 16 cities. 44.8% (39/87) and 37.9% (33/87) of the outbreaks occurred in hotels, restaurants and school canteens, respectively. Improper food processing and storage (40.2%, 35/87) and cross contamination caused by indiscriminate raw and cooked food (25.3%, 22/87) were the main causes of food-borne disease outbreaks of Vibrio parahaemolyticus. The main serotypes of patient derived strains were O3:K6 (87.5%) and O4:KUT (22.5%). The similarity value between O3:K6 type isolates was 65.5%-100.0%, and the PFGE pattern similarity value of O4:KUT type isolates was 66.5%-100.0%. Conclusion: Outbreaks caused by Vibrio parahaemolyticus are widely distributed in Guangdong province. It is necessary to strengthen the publicity and education on the correct handling of food in hotels, restaurants, schools, and unit canteens. O3:K6 and O4:KUT serotypes are the main serotypes of the outbreak. There is genetic diversity among the epidemic strains.

Effects of pyrethroids on dopamine and its metabolites in nigrostriatum of male rats / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To investigate the effects of pyrethroids on nigrostriatal dopaminergic pathways in male rats and its mechanism.</p><p><b>METHODS</b>Different doses of permethrin (PM, 200, 400 mg/kg) and deltamethrin (DM, 6.25, 12.50 mg/kg) in corn oil were administered to rats by gavage once daily for ten days, then the contents of dopamine (DA) and its metabolites, 3, 4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the substantial nigra and striatum were analyzed by HPLC-fluorescence detection.</p><p><b>RESULTS</b>The contents of DA in striatum in four administered groups were decreased to a certain extent. DA in 6.25 mg/kg DM group [(6.14 +/- 0.57) microg/g wet weight] was lower than that in control group [(9.46 +/- 1.95) microg/g wet weight], P < 0.05. The turnover rate of DA in 200, 400 mg/kg PM and 6.25, 12.5 mg/kg DM groups increased by 133.33%, 166.67%, 166.67%, 266.67% respectively (P < 0.05 or P < 0.01), however there was no significant difference in DA and DOPAC in substantial nigra between control and administered groups.</p><p><b>CONCLUSION</b>DM may inhibit tyrosine hydroxylase and decrease the level of DA in striatum, and both pyrethroid pesticides may increase the metabolism of dopamine in striatum.</p>