ABSTRACT
Since December 2019, Corona Virus Disease (COVID-19), a new emerging infection disease occurred in Wuhan, has spread in 27 countries and regions. The clusters of many cases were reported with the epidemic progresses. We collected currently available information for 377 COVID-19 clusters (1 719 cases), excluded the hospital clusters and Hubei cases, during the period from January 1, 2020 to February 20, 2020. There were 297 family clusters (79%), case median 4; 39 clusters of dining (10%), case median 5; 23 clusters of shopping malls or supermarkets (6%), case median 13; 12 clusters of work units (3%), case median 6, and 6 clusters of transportation. We selected 325 cases to estimate the incubation period and found its range is 1 to 20 days, median was 7 days, and mode was 4 days. The analysis of the epidemic situation in a department store in China indicates that there is a possibility of patients as the source of infection during the incubation period of the epidemic. From February 5, 2020 to February 21, 2020, 634 persons were infected in the Diamond Princess Liner. All persons are susceptible to SARS-CoV-2. The older, patients during the incubation period and the worse environment may be the cause of the cases rising. The progress of the two typical outbreaks clearly demonstrates the spread of the early cases in Wuhan. Whatever happens, screening and isolating close contacts remains essential except for clinical treatment during the epidemic. Especially for the healthy people in the epidemic area, isolation is the key.
ABSTRACT
Objective To analyze projects completed at the end of 2017 and funded by National Natural Science Foundation of China (NSFC) in the field of skin and its appendages,in order to provide references for preparing concluding reports and making discipline development strategies in the future.Methods The concluding reports of projects completed at the end of 2017 and funded by National Natural Science Foundation of China in the field of skin and its appendages were collected from the Internet-based Science Information System.The achievements were analyzed,including journal articles,patents,talent training and monographs.Results A total of 91 projects were completed at the end of 2017 in the field of skin and its appendages,and the total cost of funds was 43.51 million RMB Yuan.A total of 452 journal articles were published,including 324 articles in the Science Citation Index (SCI)-indexed journals and 42 in the A Guide to the Core Journal of China-indexed journals.Additionally,0.74 SCI journal article and 0.10 Chinese core journal article could be produced per 100 000 RMB Yuan.The average impact factor of journals publishing these SCI articles was 3.972,and in average,100 000 RMB Yuan yielded 1 article in the journal with an impact factor of 2.92.Of the 324 published articles,46 and 102 were published in journals ranked within the first (Q1) and second (Q2) quartile,respectively,by Chinese Academy of Sciences.In all the SCI articles,14 were published in journals with impact factor of ＞ 10.There were 4 institutions with more than 5 completed projects,and a total of 129 (39.84％) SCI articles were published.Published SCI articles in the field of immune skin diseases accounted for the highest proportion (148/324,45.68％).A total of 152 talents were trained.Conclusions The support of NSFC in basic researches in the field of skin and its appendages has led to substantial achievements.More attention should be paid to the writing of concluding reports.Innovation consciousness should be raised,and project leaders should make more original and leading achievements in the future.
ABSTRACT
We analyzed the project results of preventive medicine from the National Natural Science Foundation of China (NSFC) finished in 2017 based on the project-ending reports and data on science fund sharing service network. A total of 406 projects in this field were completed in 2017. A total of 3 122 published articles supported by these projects, including 1 789 articles in science citation index (SCI) journals and 525 articles in Chinese core journals. In addition, there were 224 patent application/software copyright and 589 trained postgraduates. The top three sub-disciplines of project were non-communicable disease epidemiology, human nutrition and hygienic toxicology, accounting for 45.32% of the total number of completed projects. There were 12 institutions which had more than 10 finished projects, accounting for 41.87%. During the recent 5 years, the number of SCI articles and patents/software copyrights per project showed a general uptrend. It should be noted that the number of articles in Chinese core journals and postgraduates decreased in recent two years. Our analyses demonstrated that the project results should be guided by the new era policy of science fund to promote sustainable development of scientific research.
ABSTRACT
Objective To analyze the effect of the identification and evaluation of Escherichia (E.) coli and Shigella,based on the upstream flanking sequences of CRISPR1.Methods Both CRISPR and cas sequences were obtained through the BLAST with repeating sequences against the publicly complete genome in GenBank that related to E.coli and Shigella.Clustal X was used to perform multi-sequences alignment of the flanking sequences.PCR method was used to amplify the upstream flanking sequences of CRISPR1 in order to appraise the effect of identification and evaluation of upstream flanking sequences on E.coli and Shigella,which were based on the upstream flanking sequences of CRISPR1.Results The results showed that 73.4％ of the strains containing the I-E CRISPR/Cas that belonged to the phylogroups A,B1,D while 8.4％ strains carried the I-F CRISPR/Cas.Another 17.2％ of the strains owned CRISPR3-4 (non-CRISPR/Cas) only belonged to the phylogroups B2.All the Shigella strains carried I-E CRISPR/Cas.More than 99％ of similarity the CRISPR1 upstream-flanking sequences was seen in E.coli (except B2) and Shigella and E.coli (B2).Both sensitivity and specificity were greater than 91％ after PCR amplification in the region to identify the E.coli and Shigella.Conclusion The upstream of CRISPR1 could achieve a preliminary identification effect on E.coli and Shigella.
ABSTRACT
Objective To analyze the effect of the identification and evaluation of Escherichia (E.) coli and Shigella,based on the upstream flanking sequences of CRISPR1.Methods Both CRISPR and cas sequences were obtained through the BLAST with repeating sequences against the publicly complete genome in GenBank that related to E.coli and Shigella.Clustal X was used to perform multi-sequences alignment of the flanking sequences.PCR method was used to amplify the upstream flanking sequences of CRISPR1 in order to appraise the effect of identification and evaluation of upstream flanking sequences on E.coli and Shigella,which were based on the upstream flanking sequences of CRISPR1.Results The results showed that 73.4％ of the strains containing the I-E CRISPR/Cas that belonged to the phylogroups A,B1,D while 8.4％ strains carried the I-F CRISPR/Cas.Another 17.2％ of the strains owned CRISPR3-4 (non-CRISPR/Cas) only belonged to the phylogroups B2.All the Shigella strains carried I-E CRISPR/Cas.More than 99％ of similarity the CRISPR1 upstream-flanking sequences was seen in E.coli (except B2) and Shigella and E.coli (B2).Both sensitivity and specificity were greater than 91％ after PCR amplification in the region to identify the E.coli and Shigella.Conclusion The upstream of CRISPR1 could achieve a preliminary identification effect on E.coli and Shigella.
ABSTRACT
Objective To investigate the association between phage-mediated shiga toxin and molecular distribution of CRISPR in Escherichia (E.) coli O26:H11 or NM.Methods A total of 135 E.coli O26:H11 or NM strains were collected from NCBI database.Software CRT and CRISPR Finder were used to extract CRISPR and Excel was used to assign the spacer of unique number and type CRISPR.And the relationship between CRISPR and stx phage was analyzed.Results All the 135 E.coli O26:H11 or NM strains had the CRISPR.For CRISPRI,CRISPR2.1,CRISPR2.2 and CRISPR3-4,19,22,1 and 1 subtypes were found,respectively.According to the four CRISPR sites,the strains could be divided into 40 subtypes.Stx-phage was only observed in the group C of CRISPR.Compared with E.coli of stx-phage negative,E.coli with stx-phage harbored more spacers.Conclusions CRISPR loci was extensively existed in E.coli O26:H11 or NM,and many subtypes were found in these strains.The presence of stx-phage was related to the molecular distribution of CRISPR in E.coli O26:H11 or NM.CRISPR might be a valuable biomarker to identify strains with high virulent potential.
ABSTRACT
Objective To investigate the association between phage-mediated shiga toxin and molecular distribution of CRISPR in Escherichia (E.) coli O26:H11 or NM.Methods A total of 135 E.coli O26:H11 or NM strains were collected from NCBI database.Software CRT and CRISPR Finder were used to extract CRISPR and Excel was used to assign the spacer of unique number and type CRISPR.And the relationship between CRISPR and stx phage was analyzed.Results All the 135 E.coli O26:H11 or NM strains had the CRISPR.For CRISPRI,CRISPR2.1,CRISPR2.2 and CRISPR3-4,19,22,1 and 1 subtypes were found,respectively.According to the four CRISPR sites,the strains could be divided into 40 subtypes.Stx-phage was only observed in the group C of CRISPR.Compared with E.coli of stx-phage negative,E.coli with stx-phage harbored more spacers.Conclusions CRISPR loci was extensively existed in E.coli O26:H11 or NM,and many subtypes were found in these strains.The presence of stx-phage was related to the molecular distribution of CRISPR in E.coli O26:H11 or NM.CRISPR might be a valuable biomarker to identify strains with high virulent potential.
ABSTRACT
Molecular epidemiology,a branch of epidemiology,combines the theories and methods,both in epidemiology and molecular biology.Molecular epidemiology mainly focuses on biological markers,describing the distribution,occurrence,development and prognosis of diseases at the molecular level.The completion of Human Genome Project and rapid development of Precision Medicine and Big Data not only offer the new development opportunities but also bring about a higher demand and new challenge for molecular epidemiology.
ABSTRACT
Molecular epidemiology,a branch of epidemiology,combines the theories and methods,both in epidemiology and molecular biology.Molecular epidemiology mainly focuses on biological markers,describing the distribution,occurrence,development and prognosis of diseases at the molecular level.The completion of Human Genome Project and rapid development of Precision Medicine and Big Data not only offer the new development opportunities but also bring about a higher demand and new challenge for molecular epidemiology.