Initial chest CT findings in COVID-19: correlation with clinical features / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

In December 2019, coronavirus disease 2019 (COVID-19), a new de novo infectious disease, was first identified in Wuhan, China and quickly spread across China and around the world. The etiology was a novel betacoronavirus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (Lu et al., 2020). On Mar. 11, 2020, World Health Organization (WHO) characterized COVID-19 as a global pandemic. As of Mar. 22, 2020, over 292 000 confirmed COVID-19 cases have been reported globally. To date, COVID-19, with its high infectivity, has killed more people than severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) combined (Wu and McGoogan, 2020).

Thinking on Oncomelania hupensis snail control by comprehensive control measures combined with"a total of five-water treatment" / 中国血吸虫病防治杂志

Oncomelania hupensis is the only intermediate host of Schistosoma japonicum,and it has a significant influence on the transmission,control and elimination of schistosomiasis.In 2016,Zhejiang Province passed the national united assessment of"maintaining the schistosomiasis elimination status";however,there are still O.hupensis snails remained in the very compli-cated environments.The breeding and spread of O.hupensis snails can be controlled for a long time with the environmental modi-fication by adapting to local circumstance and scientific development,which can reduce the potential risk of schistosomiasis transmission and promote the development of local economy and society.This paper analyzes the working conditions of schistoso-miasis prevention and control in Zhejiang Province and gives some relevant suggestions on how to guarantee the maintenance of the schistosomiasis elimination status in Zhejiang Province by the environmental modification combined with"a total of five-wa-ter treatment",which can effectively condense the local snail breeding environments in key schistosomiasis endemic regions.

Inhibitory effect of resveratrol against enterovirus type 71 in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the inhibitory effect of resveratrol against the cytopathogenicity of enterovirus type 71.</p><p><b>METHODS</b>The cytotoxicity of resveratrol on Vero cells was detected using cell counting kit-8 (CCK-8). The antiviral activity of resveratrol in different stages of infection, with ribavirin as the control, was evaluated by determining the virus inhibition rate, medium effective concentration (IC(50)), and selection index (SI).</p><p><b>RESULTS</b>Resveratrol was nonpoisonous to Vero cells with an median toxic concentration (TC50) of 307.6 mmol/L. Resveratrol produced an obvious inhibitory effect against enterovirus type 71 only before the cell infection by the virus (IC(50)=20.2 mmol/L , SI=15.2), and once the cells were infected, resveratrol no longer had such antiviral effect.</p><p><b>CONCLUSIONS</b>Resveratrol may offer some protection against enterovirus type 71 in vitro.</p>

An analysis of the characteristics and etiology of hand, foot and mouth disease in a Guangzhou sentinel hospital from May to December, 2008 / 南方医科大学学报

<p><b>OBJECTIVE</b>To analyze the characteristics and etiology of hand, foot and mouth disease (HFMD) in a sentinel hospital of Guangzhou.</p><p><b>METHODS</b>The epidemiological data and clinical specimens were collected from May to December, 2008 for virological investigations (viral isolation, RT-PCR and molecular identification) and phylogenetic analysis.</p><p><b>RESULTS</b>A total of 309 clinical cases were reported, and the incidence was the highest in 2-4-year-old children, among whom only 15 developed complications, with human enterovirus 71 (HEV71) as the main pathogen (64.7%). Phylogenetic analysis indicated that ten Guangzhou EV71 isolates belonged to Cluster C4a.</p><p><b>CONCLUSION</b>HFMD is an important infectious disease in children resulting from infections by HEV71 as the main pathogen in 2008, and the Guangzhou C4a strains co-evolved with the isolates from other provinces in China and the neighboring countries.</p>

Establishment of an artificial neural network model for analysis of the influence of climate factors on the density of Aedes albopictus / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a model for predicting the density of Aedes albopictus based on the climate factors.</p><p><b>METHODS</b>The data of Aedes albopictus density and climate changes from 1995 to 2001 in Guangzhou were collected and analyzed. The predicting model for Aedes albopictus density was established using the Artificial Neural Network Toolbox of Matlab 7.0 software package. The climate factors used to establish the model included the average monthly pressure, evaporation capacity, relative humidity, sunshine hour, temperature, wind speed, and precipitation, and the established model was tested and verified.</p><p><b>RESULTS</b>The BP network model was established according to data of mosquito density and climate factors. After training the neural network for 25 times, the error of performance decreased from 0.305 539 to 2.937 51x10(-14). Verification of the model with the data of mosquito density showed a concordance rate of prediction of 80%.</p><p><b>CONCLUSION</b>The neural network model based on the climate factors is effective for predicting Aedes albopictus density.</p>

Establishment and application of a loop-mediated isothermal amplification method for rapid diagnosis of Vibrio cholerae / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a loop-mediated isothermal amplification (LAMP) method for rapid diagnosis of Vibrio cholerae.</p><p><b>METHODS</b>Based on the ompW nucleic sequence of Vibrio cholerae, a pair of primers was designed for LAMP. The reaction conditions were optimized, and the specificity, sensitivity, and practicability of LAMP were tested using 47 bacterial strains and simulated contaminated sites.</p><p><b>RESULTS</b>The results of viable bacterium count showed that LAMP was capable of detecting Vibrio cholerae at a level as low as 1.6x10(2) cfu/ml. The minimal detectable concentration was 1.6+10(3) cfu/ml for simulated contaminated samples such as feces and seawater, and 1.6+10(4) cfu/ml for contaminated milk. All the 21 strains of Vibrio cholerae yielded positive results in LAMP, and the 26 strains of other bacteria all showed negative results, with a detection specificity of 100%.</p><p><b>CONCLUSION</b>The established LAMP method has high specificity and sensitivity for detecting Vibrio cholerae and is applicable in field monitoring and epidemiological study of Vibrio cholerae.</p>

Development of a SPA-ELISA method for detecting anti-coronavirus IgG antibodies in serum samples from fulvous fruit bats / 南方医科大学学报

<p><b>OBJECTIVE</b>To develop an simple and sensitive method for detecting anti-coronavirus IgG antibodies in bat sera based on enzyme-linked immunosorbent assay (ELISA).</p><p><b>METHODS</b>A commercial ELISA kit for detecting SARS-CoV antibody was modified for detecting coronavirus antibodies in bat serum samples. The second antibody in the kit was replaced with horseradish peroxidase-conjugated protein-A (HRP-SPA) based on the characteristics of binding between Staphylococcus aureus protein A (SPA) and mammal IgG Fc fragment. The sera of 55 fulvous fruit bats (Rousettus dasymallus) were tested using the SPA-ELISA.</p><p><b>RESULTS</b>The test results of the positive and negative controls in the kit and the serum samples from convalescent ;patient were consistent with expectation. Coronavirus antibody was detected in 2 out of the 55 bat serum samples. Serum neutralization test confirmed the validity of the SPA-ELISA method.</p><p><b>CONCLUSION</b>This SPA-ELISA method is applicable for detecting coronavirus antibody in bat sera.</p>