Utility of Droplet Digital PCR Assay for Quantitative Detection of Norovirus in Shellfish, from Production to Consumption in Guangxi, China / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>Shellfish are recognized as important vehicles of norovirus-associated gastroenteritis. The present study aimed to monitor norovirus contamination in oysters along the farm-to-fork continuum in Guangxi, a major oyster production area in Southwestern China.</p><p><b>METHODS</b>Oyster samples were collected monthly from farms, markets, and restaurants, from January to December 2016. Norovirus was detected and quantified by one-step reverse transcription-droplet digital polymerase chain reaction (RT-ddPCR).</p><p><b>RESULTS</b>A total of 480 oyster samples were collected and tested for norovirus genogroups I and II. Norovirus was detected in 20.7% of samples, with genogroup II predominating. No significant difference was observed in norovirus prevalence among different sampling sites. The norovirus levels varied widely, with a geometric mean of 19,300 copies/g in digestive glands. Both norovirus prevalence and viral loads showed obvious seasonality, with a strong winter bias.</p><p><b>CONCLUSION</b>This study provides a systematic analysis of norovirus contamination 'from the farm to the fork' in Guangxi. RT-ddPCR can be a useful tool for detection and quantification of low amounts of norovirus in the presence of inhibitors found particularly in foodstuffs. This approach will contribute to the development of strategies for controlling and reducing the risk of human illness resulting from shellfish consumption.</p>

Effect of sFRP2 on the biological behavior of HepG2 cells / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To investigate the effect of sFRP2 on the biological behavior of human hepatoma carcinoma HepG2 cells.</p><p><b>METHODS</b>HepG2 cells were infected with recombinant adenovirus containing mouse sFRP2 gene, and then the proliferation, cell cycle distribution, expression of tumor metastasis related factors (CD44, CD82/KAI1, EMMPRIN) and beta-catenin protein, and migration ability of the cells were detected by MTT, FCM, immunohistochemistry, Western blot and Transwell inserts, respectively.</p><p><b>RESULTS</b>sFRP2 protein inhibited the proliferation of HepG2 cells, and increased the percentage of G0/G1 period cells. Expression of CD44 and CD82/KAI1 proteins, which could inhibit invasion and metastasis of tumor cells, was upregulated. However, EMMPRIN protein, which could promote the above properties of tumor cells decreased in HepG2 cells infected with the recombinant adenovirus containing mouse sFRP-2 gene. Western blot demonstrated that beta-catenin was expressed in HepG2 cells and there was no significant difference between the treated and the control groups. Transwell insert test showed sFRP2 protein decreased the migration ability of HepG2 cells.</p><p><b>CONCLUSION</b>The recombinant adenovirus containing mouse sFRP-2 gene could infect HepG2 cells. sFRP2 protein could significantly reduce the capability of proliferation, invasion and metastasis of HepG2 cells.</p>

Epidemiologic surveillance for bacterial meningitis in 140 000 children under 5 years of age in Nanning district, Guangxi province / 中华流行病学杂志

<p><b>OBJECTIVE</b>To characterize the incidence, epidemiologic features, etiologic agents and sequelae of bacterial meningitis in children under 5 years of age in Nanning, Guangxi.</p><p><b>METHODS</b>A population-based surveillance was conducted to evaluate children with signs and symptoms of meningitis. All hospitals, township health centers and village clinics in the surveillance area were structured to participate in the case referral and evaluation. Cerebrospinal fluid (CSF) and blood specimens were obtained and processed using standardized microbiologic methods.</p><p><b>RESULTS</b>During the 26-month surveillance period, among the children under 5 years old, a total of 1272 cases who met the screening criteria of meningitis were studied. 265 of 1272 cases were identified as clinically diagnosed meningitis, with an incidence rate of 86.36 per 100 000 population. The annual incidence rate under the 38 cases of confirmed bacterial meningitis appeared to be 12.38/100 000. Staphylococcus species accounted for the largest proportion of laboratory-confirmed bacterial meningitis, followed by E. coli and S. pneumoniae. The highest attack rate occurred in neonates < 1 month, followed by children aged 1 - 12 months in the confirmed patients. Meningitis caused by Sp and Hi mainly occurred in children aged 1 - 12 months. All cases of meningitis due to Hi and Sp were children aged 1 - 24 months. 13.16% and 0.00% of the cases survived with complications and sequelae, and the case-fatality rate was 18.42%. 40 bacterial isolates were identified from 1193 blood cultures and 23 from 1211 cerebrospinal fluid samples, but no Neisseria meningitidis was found.</p><p><b>CONCLUSION</b>Meningitis due to Hi was first confirmed in Guangxi with the incidence of 0.98 per 100 000 population. The annual incidence rate of confirmed bacterial meningitis was 12.38 per 100 000, which was considered an important public health problem in children. Staphylococci was the predominant pathogen in confirmed bacterial meningitis.</p>