Distribution of the COVID-19 Epidemic and Correlation with Population Emigration from Wuhan, China / 中华医学杂志(英文版)

Background The ongoing new coronavirus pneumonia (Corona Virus Disease 2019,COVID-19) outbreak is spreading in China, but it has not yet reached its peak. Five million people emigrated from Wuhan before lockdown, potentially representing a source of virus infection. Determining case distribution and its correlation with population emigration from Wuhan in the early stage of the epidemic is of great importance for early warning and for the prevention of future outbreaks. Methods The official case report on the COVID-19 epidemic was collected as of January 30, 2020. Time and location information on COVID-19 cases was extracted and analyzed using ArcGIS and WinBUGS software. Data on population migration from Wuhan City and Hubei province were extracted from Baidu Qianxi, and their correlation with the number of cases was analyzed. Results The COVID-19 confirmed and death cases in Hubei province accounted for 59.91% (5806/9692) and 95.77% (204/213) of the total cases in China respectively. Hot spot provinces included Sichuan and Yunnan, which are adjacent to Hubei. The time risk of Hubei province on the following day was 1.960 times that on the previous day. The number of cases in some cities was relatively low, but the time risk appeared to be continuously rising. The correlation coefficient between the provincial number of cases and emigration from Wuhan was up to 0.943. The lockdown of 17 cities in Hubei province and the implementation of nationwide control measures efficiently prevented an exponential growth in the number of cases. Conclusion The population that emigrated from Wuhan was the main infection source in other cities and provinces. Some cities with a low number of cases showed a rapid increase in case load. Owing to the upcoming Spring Festival return wave, understanding the risk trends in different regions is crucial to ensure preparedness at both the individual and organization levels and to prevent new outbreaks.

One Health strategy to prevent and control antibiotic resistance / 生物工程学报

Antibiotic resistance affects the development of the world economy and threats public health. China is one of the countries with the most severe abuse of antibiotics. Here, we describe the causes of antibiotic resistance in the environment, human and animals as well as the status of antibiotic resistance. Based on the concept of One Health, we propose the promotion of the scientific use of antibiotics, the development of new types of antibiotics, establishment of the antibiotics stereoscopic monitoring network system, the promotion of knowledge education of antibiotic resistance, prevention of infection and other measures. We call for the establishment of interdisciplinary, cross-sectoral, trans-regional communication and cooperation to promote the development of antibiotic resistance prevention and control in China to protect environment and the health of humans and animals.

Acceptance and influence factor of central slaughtering of live poultry in residents of Guangzhou / 中华预防医学杂志

<p><b>OBJECTIVES</b>To investigate a survey about acceptance of central slaughtering of live poultry in residents of Guangzhou.</p><p><b>METHODS</b>We conducted a telephone survey by sampling residents with fixed-line telephone and with normal hearing, whose age is more than 15 years, by Mitofsky-Waksberg two-stage method during Jan 6(th) to 8(th), 2014. 358 residents finished the telephone questionnaire by 12 320 health hot line. We investigated the acceptance rate of city-wide central slaughtering permanently. We compared the difference between the respondents and the 2010 Guangzhou census data by Cohen's effect sizes (w) and weighted by population age and sex. We used χ(2) test to compare the acceptance rate of central slaughtering in residents with different characteristic. We used multiple logistic regression analysis to analyze the factors.</p><p><b>RESULTS</b>The difference in gender and age was small between respondents and the 2010 Guangzhou census data (w value was 0.13, 0.28, respectively), but that in education and marital status was large (w value was 0.52, 0.31, respectively). 49.0% (95% CI: 43.7%-54.3%) accept city-wide central slaughtering permanently. The acceptance rate of city-wide central slaughtering permanently in those who bought fresh, chilled and frozen poultry in their family in previous year was 54.3% (133/245), 60.0% (57/95) and 59.8% (49/82), respectively. It was more than those who didn't buy fresh, chilled and frozen poultry (38.1% (43/113), 44.9% (118/263) and 45.7% (126/276); χ(2) values were 8.15, 6.40 and 5.03; P values were 0.004, 0.011 and 0.025, respectively). The acceptance rate of city-wide central slaughtering permanently in those who deem fresh poultry taste better than live poultry was 64.9% (24/38). It more than those who deem not (47.0%, 151/320) (χ(2) = 4.22, 6.02, P = 0.040, 0.014, respectively). The acceptance rate of city-wide central slaughtering permanently in the male (OR = 2.68, 95% CI: 1.64-4.37) and those who deem getting sick due to buying live birds from LPM (OR = 1.72, 95% CI: 1.05-2.82), who can accept only fresh poultry carcass supply (OR = 2.39, 95% CI: 1.33-4.30), Who bought live poultry in their family in previous year (OR = 0.29, 95% CI: 0.11-0.74), who will decrease the consumption after ban on live poultry sale (OR = 0.50, 95% CI: 0.30-0.83) was 58.6% (109/186), 59.0% (92/156), 60.7% (139/230), 44.9% (132/295), 36.6% (68/186), respectively.</p><p><b>CONCLUSION</b>In the early stage of avian influenza A(H7N9) epidemic in Guangzhou, the rate of acceptance of central slaughtering permanently in residents was not so high. Who deem getting sick due to buying live birds from LPM, who could accept only fresh poultry carcass supply and the male more accept city-wide central slaughtering permanently.</p>

Predicating risk area of human infection with avian influenza A (H7N9) virus by using early warning model in China / 中华流行病学杂志

<p><b>OBJECTIVE</b>To establish a risk early warning model of human infection with avian influenza A (H7N9) virus and predict the area with high risk of the outbreak of H7N9 virus infection.</p><p><b>METHODS</b>The incidence data of human infection with H7N9 virus at prefecture level in China from February 2013 to June 2014 were collected, and the geographic and meteorological data during the same period in these areas were collected too. Spatial auto regression (SAR) model and generalized additive model (GAM) were used to estimate different risk factors. Afterwards, the risk area map was created based on the predicted value of both models.</p><p><b>RESULTS</b>All the human infections with H7N9 virus occurred in the predicted areas by the early warning model in February 2014. The early warning model successfully predicted the spatial moving trend of the disease, and this trend was verified by two outbreaks in northern China in April and May 2014.</p><p><b>CONCLUSION</b>The established early warning model showed accuracy and precision in short-term prediction, which might be applied in the active surveillance, early warning and prevention/control of the outbreak of human infection with H7N9 virus.</p>

Prediction of H7N9 epidemic in China / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>In March 2013, human cases of infection with a novel A (H7N9) influenza virus emerged in China. The epidemic spread quickly and as of 6 May 2013, there were 129 confirmed cases. The purpose of this study was to analyze the epidemiology of the confirmed cases, determine the impacts of bird migration and temperature changes on the H7N9 epidemic, predict the future trends of the epidemic, explore the response patterns of the government and propose preventive suggestions.</p><p><b>METHODS</b>The geographic, temporal and population distribution of all cases reported up to 6 May 2013 were described from available records. Risk assessment standard was established by analysing the temperature and relative humidity records during the period of extensive outbreak in three epidemic regions in eastern China, including Shanghai, Zhejiang and Jiangsu provinces. Risk assessment maps were created by combining the bird migration routes in eastern China with the monthly average temperatures from May 1993 to December 2012 nationwide.</p><p><b>RESULTS</b>Among the confirmed cases, there were more men than women, and 50.4% were elderly adults (age >61 years). The major demographic groups were retirees and farmers. The temperature on the days of disease onset was concentrated in the range of 9°C-19°C; we defined 9°C-19°C as the high-risk temperature range, 0°C-9°C or 19°C-25°C as medium risk and <0°C or >25°C as low risk. The relative humidity on the days of disease onset ranged widely from 25% to 99%, but did not correlate with the incidence of infection. Based on the temperature analysis and the eastern bird migration routes, we predicted that after May, the high-risk region would move to the northeast and inland, while after September, it would move back to north China.</p><p><b>CONCLUSIONS</b>Temperature and bird migration strongly influence the spread of the H7N9 virus. In order to control the H7N9 epidemic effectively, Chinese authorities should strengthen the surveillance of migrating birds, increase poultry and environmental sampling, improve live poultry selling and husbandry patterns and move from a "passive response pattern" to an "active response pattern" in focused preventive measures.</p>

Expression of Human Connexin26 in COS-7 Cells / 热带医学杂志

Objective To construct the eukaryotic expression plasmid for the expression of human Connexin26 in COS-7 cells.Methods Total RNA was isolated from human peripheral blood lymphocytes and used as template for the PCR cloning of the human Connexin26 gene.The human Cx26 cDNA containing the 678 bp whole coding region of the human Connexin26 gene was amplified by PCR using specific primers and cloned into the pCI-neo vector to construct the recombinant eukaryotic expression plasmid,pCI-Cx26.The recombinant plasmid was identified by restriction endonuclease digestion,and transfected into COS-7 cells by liposome.The expression of Cx26 mRNA and the protein were analyzed by RT-PCR and SDS-PAGE,respectively.Results Restriction endonuclease digestion analysis verified successful construction of the recombinant plasmid,pCI-Cx26.The expression of Cx26 mRNA and protein in the transfected COS-7 cells were detected by RT-PCR and SDS-PAGE,respectively.Conclusion The eukaryotic expression plasmid for human Cx26 has been constructed successfully with the capability of expression in COS-7 cells.

Inhibiting severe acute respiratory syndrome-associated coronavirus by small interfering RNA / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To evaluate the effectiveness of small interfering RNA (siRNA) on inhibiting severe acute respiratory syndrome (SARS)-associated coronavirus replication, and to lay bases for the future clinical application of siRNA for the treatment of viral infectious diseases.</p><p><b>METHODS</b>Vero-E6 cells was transfected with siRNA before SARS virus infection, and the effectiveness of siRNA interference was evaluated by observing the cytopathic effect (CPE) on Vero-E6 cells.</p><p><b>RESULTS</b>Five pairs of siRNA showed ability to reduce CPE dose dependently, and two of them had the best effect.</p><p><b>CONCLUSION</b>siRNA may be effective in inhibiting SARS-associated coronavirus replication.</p>

Construction of Eukaryotic Expression Recombinant Plasmid and Sequence Analysis of p41-3 Gene of Plasmodium Falciparum Isolate FCC1/HN / 中山大学学报(医学科学版)

[Objective] To construct a eukaryotic expression plasmid containing a gene encoding a 41-3 kilodalton blood stage antigen (p41-3) of Plasmodiu falciparum isolate FCC1/HN, and to determine the sequence of p41-3 gene and analyze the homology of the sequences of 341-3 gene of different P. falciparum isolates. [ Methods] Two pairs of primers were designed according to the known sequence of p41-3 gene. Using PCR technique, the p41-3 gene was obtained by amplification from genomic DNA of isolate FCC1/HN. By cloning target gene into a eukaryotic expression vector, pcDNA3, a recombinant plasmid pcDNA3-p41-3 was con structed and trarsferred into E. coli DH5α. The positive clones were screened and identified by agarose gel electrophoresis, endonu clease digestion and PCR technique. The correct recombinant plasmid pcDNA3-p41-3 was used as template, and the nucleotide se quence of p41-3 gene was determined by the dideoxy chain termination method. Using softwares to analyze the structure and sequence homology of p41-3 gene between isolate FCC1/HN and FCBR. [Results] The p41-3 gene was specifically amplified from genomic DNA of Plasmodiumm falciparum isolate FCC1/HN, and the correct recombinant plasmid pcDNA3-p41-3 was screened and identi fied. The result of sequence determination showed that the p41-3 gene of isolate FCC1/HN was 2 137 base pairs in full length, encod ing 375 amino acids. Isolate FCC1/HN and isolate FCBR exhibited 98.98 % homology in the nucleiotide sequences and 99.73 % ho mology in the encoded anino acids of p41-3 gene. [Conclusion] The eukaryotic expression plasmid pcDNA3-p41-3 is successfully con structed and nucleotide sequence of p41-3 gene of isolate FCC1/HN is determined. The p41-3 genes of isolate FCC1/HN and isolate FCBR share quite high homology.

Detection of CTP gene expression in the asexual erythrocytic stages of Plasmodium falciparum (FCC1 /HN) by reverse transcriptase- polymerase chain reaction and construction of eukaryotic expression vector of CTP gene / 热带医学杂志

Objectve To detect whether the CTP(phosphocholine cytidylyltransferase) gene was expressed in the asexual erythrocytic stages of Plasmodium falciparum (FCC 1/HN )by using the RT - PCR and to construct eukaryotic expression vector of CTP. Method The erythrocytic stage parasites of Plasmodium falciparum were cultured as described by Trager and Jensen. RNA from erythrocytic stage parasite was extracted by using Trizol reagent. The complete genes coding for CTP gene isolates FCCI/HN were amplified by reverse transcriptase -polymerase chain reaction(RT- PCR). CTP gene was cloned into eukaryotic expression vector pcDNA3. Results CTP encoding gene was amplified from the erythrocytic stages of Plasmodiumfalciparum (FCC 1/HN) and eukaryotic expression vector of CTP was constructed. Conclusion CTP gene was expressed in the erythrocytic stages of Plasmodium falciparum (FCC 1/HN) and eukaryotic expression vector of CTP was successfully constructed.

Effect of inactivated SARS coronavirus vaccine on mouse organs / 中国病理生理杂志

AIM: To study the pathological change in mouse organs immunitied by inactivated SARS-CoV vaccine. METHODS: Inactivated SARS-CoV vaccine was injected into BALB/c and C57BL/6 mice. Anti-SARS antibody was analyzed by ELISA. After 8 weeks, the immunitied mice were killed and those organs were analyzed by pathological methods. RESULTS: Anti-SARS antibody in mice was positive after 8 days. Only minimal injury was observed in a few lungs and livers, but the other organs were not. CONCLUSIONS: Inactivated SARS-CoV vaccine induced mice to create antibody, whereas they did not cause severe injury. This result will be valuable for vaccine into clinical research. [

Humoral immune responses in rabbits with an experimental SARS-CoV inactivated vaccine / 中国免疫学杂志

Objective:To evaluate the immunogenicity of an experimental SARS-CoV inactivated vaccine.Methods:The virus suspension of F69 strain was inactivated with 0.4% formaldehyde and purified,then used as the immune antigen combined with Freund′s adjuvant.Eight adult New Zealand rabbits were immunized 4 times with this vaccine.12 sets of rabbit serum were sampled from the third day to 74th day after first immunization.Titers of specific IgG antibody and neutralizing antibody were determined by indirect ELISA and micro-cytopathic effect neutralizing test.Results:Rapid and potent humoral immune responses were induced by F69 inactivated vaccine in all eight immunized rabbits.Both specific IgG antibody and neutralizing antibody all peaked just with 2 vaccinations,with the maximum titer of 1∶81 920 and 1∶20 480 respectively about 6 weeks after first immunization.Across neutralizing reaction existed between F69 and Z2-Y3 strains.Conclusion:F69 inactivated vaccine owns strong immunogenicity.Similar antigenic epitopes exist between the F69 strain and Z2-Y3 strain,which ensured the cross neutralizing reaction.