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Novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is pandemic. However, data concerning the epidemiological features, viral shedding, and antibody dynamics between asymptomatic SARS-CoV-2 carriers and COVID-19 patients remain controversial. We enrolled 193 subjects infected with SARS-CoV-2 in Ningbo and Zhoushan, Zhejiang, China from January 21 to March 6, 2020. All subjects were followed up to monitor the dynamics of immunoglobulin M (IgM) and IgG against SARS-CoV-2. Of those, 31 were asymptomatic carriers, 149 were symptomatic patients, and 14 were presymptomatic patients. Compared to symptomatic patients, asymptomatic carriers were younger and had higher levels of white blood cell and lymphocyte, lower levels of C-reactive protein and viral load, and shorter viral shedding duration. Conversion of IgM from positive to negative was shorter in asymptomatic carriers than in COVID-19 patients (P=0.030). The proportion of those persistently seropositive for IgG was higher in COVID-19 patients than in asymptomatic carriers (P=0.037). Viral load was higher in symptomatic than presymptomatic patients. Viral shedding was longer in presymptomatic patients than in asymptomatic carriers. Conclusively, asymptomatic carriers have a higher antiviral immunity to clear SARS-CoV-2 than do symptomatic patients and this antiviral immunity is not contributable to humoral immunity.
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BackgroundSARS-CoV-2-caused coronavirus disease (COVID-19) is posing a large casualty. The features of COVID-19 patients with and without pneumonia, SARS-CoV-2 transmissibility in asymptomatic carriers, and factors predicting disease progression remain unknown. MethodsWe collected information on clinical characteristics, exposure history, and laboratory examinations of all laboratory-confirmed COVID-19 patients admitted to PLA General Hospital. Cox regression analysis was applied to identify prognostic factors. The last follow-up was February 18, 2020. ResultsWe characterized 55 consecutive COVID-19 patients. The mean incubation was 8.42 (95% confidence interval [CI], 6.55-10.29) days. The mean SARS-CoV-2-positive duration from first positive test to conversion was 9.71 (95%CI, 8.21-11.22) days. COVID-19 course was approximately 2 weeks. Asymptomatic carriers might transmit SARS-CoV-2. Compared to patients without pneumonia, those with pneumonia were 15 years older and had a higher rate of hypertension, higher frequencies of having a fever and cough, and higher levels of interleukin-6 (14.61 vs. 8.06pg/mL, P=0.040), B lymphocyte proportion (13.0% vs.10.0%, P=0.024), low account (<190/{micro}L) of CD8+ T cells (33.3% vs. 0, P=0.019). Multivariate Cox regression analysis indicated that circulating interleukin-6 and lactate independently predicted COVID-19 progression, with a hazard ratio (95%CI) of 1.052 (1.000-1.107) and 1.082 (1.013-1.155), respectively. During disease course, T lymphocytes were generally lower, neutrophils higher, in pneumonia patients than in pneumonia-free patients. CD8+ lymphocytes did not increase at the 20th days after illness onset. ConclusionThe epidemiological features are important for COVID-19 prophylaxis. Circulating interleukin-6 and lactate are independent prognostic factors. CD8+ T cell exhaustion might be critical in the development of COVID-19.
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Objective To establish a real-time quantitative PCR (RT-PCR) preliminary screening method for rapid detection of Brucella.Methods Based on the nucleotide sequence encoding Brucella's outer membrane proteins omp10 and omp31,four primers and probes of omp10,omp10-1,omp31 and omp31-1 were designed.The primers and probes were used to detect 19 strains of 6 categories of Brucella DNA of known organisms,10 strains of Brucella DNA that were isolated from Yuxi of Yunnan.And 224 negative Brucella DNA,including 35 strains of Bartonella DNA,103 strains of the Lord Komori enterocolitis DNA (including 4 parts of O ∶ 3 and 9 parts of O ∶ 9) and 86 samples of hybrids bacteria DNA.Then the specificity of primers and probes were evaluated based on the test results.Results The DNA of 19 standard Brucella strains could be amplified by omp10 and omp10-1,and the peak time and amplification curve of omp10 is better than omp10-1,and the DNA of negative control strains could not be amplified by omp10.The DNA of 16 standard Brucella strains could be amplified by omp31-1.The DNA of standard Brucella strains could not be amplified by omp31.The average Ct values of 10 strains of Brucella DNA which were isolated from Yuxi of Yunnan that were detected by omp10,omp10-1 and omp31-1 respectively were 19.87,19.14 and 17.52.Conclusion Omp10 has strong specificity and only specific for Brucella,so it can be used for rapid detection of Brucella.
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Objective To investigate whether plague phages were present in the indicator animals of plague foci in Yunnan Province,and to explore their epidemiological significance.Methods Anus swabs were collected from indicator animals (dogs or cats) of the 41 plague affected villages in 26 towns of 10 cities (counties,districts) of Yunnan plague foci from November of 2015 to March of 2018.The Yersinia pestis phages were isolated by plague vaccine strain EV76.The isolation of plague phages from different plague foci,the isolation of plague phages from different canine species (cats),the polymorphism of plaque and the host spectrum of phages were analyzed.Results A total of 1 014 indicator animals (1 003 dogs and 11 cats) were studied,and 102 of plague phages were isolated.In the 10 cities (counties,districts),plague phages were only not isolated from Lancang County,and the plague phages were isolated from the other 9 cities (counties,districts).The separation rates from high to low were as follows:Yiliang County (21.00%,21/100),Menghai County (19.23%,25/130),Yuanjiang County (11.63%,10/86),Midu County (11.50%,13/113),Wenshan County (10.10%,10/99),Mile Country (7.07%,7/99),Lianghe County (6.67%,7/105),Baoshan Longyang District (4.90%,5/102) and Gengma County (3.81%,4/105).Of the 102 plague phages,75 were isolated from the native dogs (Chinese pastoral dogs,9.32%,75/805),20 from the pug dogs (13.70%,20/146),5 from the wolf dogs (17.24%,5/29),1 from Samoye (1/4) and 1 from Alaska dog (1/2).The plaque of the phage was divided by five appearance of complete lysis (the plate was clear),large (2.5-4.0 mm),big (1.5-< 2.5 mm),middle (0.5-< 1.5 mm) and small (< 0.5 mm).The representative phages were all of the Myoviridae family.Most of the phages could lysis the strains of Yersinia pestis,and some phages could lysis Shigella and type 5 Yersinia pseudotuberculosis (PST5).Conclusion The plague phages are present in the plague foci of Yunnan,and the phages are polymorphic.
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Objective@#To investigate whether plague phages were present in the indicator animals of plague foci in Yunnan Province, and to explore their epidemiological significance.@*Methods@#Anus swabs were collected from indicator animals (dogs or cats) of the 41 plague affected villages in 26 towns of 10 cities (counties, districts) of Yunnan plague foci from November of 2015 to March of 2018. The Yersinia pestis phages were isolated by plague vaccine strain EV76. The isolation of plague phages from different plague foci, the isolation of plague phages from different canine species (cats), the polymorphism of plaque and the host spectrum of phages were analyzed.@*Results@#A total of 1 014 indicator animals (1 003 dogs and 11 cats) were studied, and 102 of plague phages were isolated. In the 10 cities (counties, districts), plague phages were only not isolated from Lancang County, and the plague phages were isolated from the other 9 cities (counties, districts). The separation rates from high to low were as follows: Yiliang County (21.00%, 21/100), Menghai County (19.23%, 25/130), Yuanjiang County (11.63%, 10/86), Midu County (11.50%, 13/113), Wenshan County (10.10%, 10/99), Mile Country (7.07%, 7/99), Lianghe County (6.67%, 7/105), Baoshan Longyang District (4.90%, 5/102) and Gengma County (3.81%, 4/105). Of the 102 plague phages, 75 were isolated from the native dogs (Chinese pastoral dogs, 9.32%, 75/805), 20 from the pug dogs (13.70%, 20/146), 5 from the wolf dogs (17.24%, 5/29), 1 from Samoye (1/4) and 1 from Alaska dog (1/2). The plaque of the phage was divided by five appearance of complete lysis (the plate was clear), large (2.5-4.0 mm), big (1.5-< 2.5 mm), middle (0.5-< 1.5 mm) and small (< 0.5 mm). The representative phages were all of the Myoviridae family. Most of the phages could lysis the strains of Yersinia pestis, and some phages could lysis Shigella and type 5 Yersinia pseudotuberculosis (PST5).@*Conclusion@#The plague phages are present in the plague foci of Yunnan, and the phages are polymorphic.
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BACKGROUND@#We previously showed that the expression of follistatin-like protein 1 (FSTL1) was significantly down-regulated in metastatic clear-cell renal cell carcinoma (ccRCC). In this study, we aimed to characterize the role of FSTL1 in the development of ccRCC.@*METHODS@#The effects of FSTL1 on cell activity and cell cycle were investigated in ccRCC cell lines with altered FSTL1 expression. Gene expression microarray assays were performed to identify the major signaling pathways affected by FSTL1 knockdown. The expression of FSTL1 in ccRCC and its effect on postoperative prognosis were estimated in a cohort with 89 patients.@*RESULTS@#FSTL1 knockdown promoted anchorage-independent growth, migration, invasion, and cell cycle of ccRCC cell lines, whereas FSTL1 overexpression attenuated cell migration. FSTL1 knockdown up-regulated nuclear factor-κB (NF-κB) and hypoxia-inducible factor (HIF) signaling pathways, increased epithelial-to-mesenchymal transition, up-regulated interleukin-6 expression, and promoted tumor necrosis factor-α-induced degradation of NF-κB inhibitor (IκBα) in ccRCC cell lines. FSTL1 immunostaining was selectively positive in epithelial cytoplasm in the loop of Henle, and positive rate of FSTL1 was significantly lower in ccRCC tissues than in adjacent renal tissues (P < 0.001). The multivariate Cox regression analysis showed that the intratumoral FSTL1 expression conferred a favorable independent prognosis with a hazard ratio of 0.325 (95% confidence interval 0.118-0.894). HIF-2α expression was negatively correlated with FSTL1 expression in ccRCC specimens (r = - 0.229, P = 0.044). Intratumoral expression of HIF-2α, rather than HIF-1α, significantly predicted an unfavorable prognosis in ccRCC (log-rank, P = 0.038).@*CONCLUSIONS@#FSTL1 plays a tumor suppression role possibly via repressing the NF-κB and HIF-2α signaling pathways. To increase FSTL1 expression might be a candidate therapeutic strategy for metastatic ccRCC.
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Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Basic Helix-Loop-Helix Transcription Factors , Genetics , Carcinoma, Renal Cell , Genetics , Pathology , Cell Line, Tumor , Cell Movement , Genetics , Disease-Free Survival , Epithelial-Mesenchymal Transition , Genetics , Follistatin-Related Proteins , Genetics , Gene Expression Regulation, Neoplastic , Genetics , Hypoxia-Inducible Factor 1, alpha Subunit , Genetics , NF-kappa B , Genetics , Neoplasm Metastasis , Signal Transduction , Genetics , Tumor Suppressor Proteins , GeneticsABSTRACT
Objective To investigate whether the host animals of Yulong plague foci carry Yersiniapestis phage,and to identify isolated plague phage.Methods Rodent specimens were collected in 5 villages of Yulong plague foci in spring and autumn of 2016,respectively.Vaccine strain EV76 was used as breeding bacteria.Phage was isolated from the specimens by double-layer plate method and plaque morphology was identified.Results ① Totally 409 samples collected in spring failed in phage isolation.A total of 40 of Yersinia pestis phages were isolated from 444 samples in autumn,and the total isolation rate was 9.01% (40/444).② The Yersinia pestis phages were isolated in all of 5 villages,and the isolation rate was of no significant difference (x2 =5.055,P > 0.05).③ Of the 40 strains of phage,37 strains were isolated from Apodemus chevrieri,2 strains from Eothenomys Miletus and 1 strain from Crocidura Dracula.④Based on the appearance,the plaque of the phage was divided into three:large (diameter 1.5-2.5 mm),middle (0.5-< 1.5 mm) and small (< 0.5 mm).Conclusion There is a higher number of plague phage in the host animals of the plague foci in Yulong County of Yunnan Province,the plaques are diverse in morphology,and their biological characteristics may be polymorphic.
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Objective To understand the genotype of the Yersinia (Y.) pestis strains isolated from Heqing county,Yunnan province in 2017 and provide evidence for the prevention and control of plague in this area.Methods Ten Y.pestis strains isolated from Heqing were typed by the detections of different region (DFR) and clustered regularly interspaced short palindromic repeats (CRISPRs) as well as multiple-locus variable-number tandem repeat analysis (MLVA).And the results were compared with those of the 93 Y.pestis strains from the adjacent plague foci of Heqing obtained from the established database for clustering analysis.Results The results showed that Heqing strains had the same type of DFR (Genomovar 05) and CRISPRs (Cluster Ca7,Type 22) with isolates from the plague focus in Lijiang.Heqing strains and Lijiang strains were in the same cluster in MST and only VNTR loci N2117 and M23 of Heqing strains were different from that of Lijiang strains.Conclusion The Y.pestis strains isolated from Heqing in 2017 were highly homogenous with the strains isolated from wild rodents in plague focus in Lijiang,and Heqing plague might be the result of further southward spread of Lijiang plague.
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Epidemiology is a traditional subject mainly based on principles and concepts,and its teaching method needs further improving to meet the requirement of the new trend of education reform.Lecture-based teaching,problem-based teaching,case-based teaching,and intemet based teaching,such as flip class,massive open online course and micro-lecture,all have its own unique merits in the practice of epidemiology teaching.So the combination of traditional teaching and online teaching is the most promising mode."Rain class",a mixed mode,is an efficient tool to present the epidemiology case more actually in class.Thus,teaching design and application of "rain class" are worth research.
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Objective: To understand the genotype of the Yersinia (Y.) pestis strains isolated from Heqing county, Yunnan province in 2017 and provide evidence for the prevention and control of plague in this area. Methods: Ten Y. pestis strains isolated from Heqing were typed by the detections of different region (DFR) and clustered regularly interspaced short palindromic repeats (CRISPRs) as well as multiple-locus variable-number tandem repeat analysis (MLVA). And the results were compared with those of the 93 Y. pestis strains from the adjacent plague foci of Heqing obtained from the established database for clustering analysis. Results: The results showed that Heqing strains had the same type of DFR (Genomovar 05) and CRISPRs (Cluster Ca7, Type 22) with isolates from the plague focus in Lijiang. Heqing strains and Lijiang strains were in the same cluster in MST and only VNTR loci N2117 and M23 of Heqing strains were different from that of Lijiang strains. Conclusion: The Y. pestis strains isolated from Heqing in 2017 were highly homogenous with the strains isolated from wild rodents in plague focus in Lijiang, and Heqing plague might be the result of further southward spread of Lijiang plague.
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Animals , China/epidemiology , Epidemiological Monitoring , Genotype , Minisatellite Repeats , Molecular Typing , Plague/microbiology , Rodentia/microbiology , Yersinia pestis/pathogenicityABSTRACT
Epidemiology is a traditional subject mainly based on principles and concepts, and its teaching method needs further improving to meet the requirement of the new trend of education reform. Lecture-based teaching, problem-based teaching, case-based teaching, and internet based teaching, such as flip class, massive open online course and micro-lecture, all have its own unique merits in the practice of epidemiology teaching. So the combination of traditional teaching and online teaching is the most promising mode. "Rain class" , a mixed mode, is an efficient tool to present the epidemiology case more actually in class. Thus, teaching design and application of "rain class" are worth research.
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Humans , Computer-Assisted Instruction , Epidemiology/education , Internet , Online Systems , Research , TeachingABSTRACT
Objective To clarify the incidence and survival of colorectal carcinoma (CRC) patients among permanent residents in Yangpu district of Shanghai,from 2002 to 2012.Methods Data of CRC patients in permanent residents of Yangpu district were collected from the database of the registration and management system in Shanghai city.Temporal trend in the incidence of CRC was analyzed by using Annual Percent Change (APC) model.Kaplan-Meier analysis with Log-rank testing was employed to estimate the survival.Incidence and mortality rates were standardized on age composition of standard population from 2000 nationwide census.Results A total of 5 881 CRC cases were diagnosed from 2002 to 2012 with crude incidence as 50.60/105 and standardized one as 31.21/105.The crude incidence rates of colon cancer and rectal cancer were 31.09/105 and 18.27/105,respectively and the standardized rates were 14.49/105 and 8.83/105,respectively.The incidence rates of colon cancer were not significantly different between different gender.However,the incidence of rectal cancer in males was significantly higher than in females (P<0.001).The incidence rates of CRC significantly increased in the age group older than 50 years.However,the standardized incidence rate did not change significantly (APC=0.39).A total of 3 735 cases died of CRC in this period.The annual crude mortality of CRC was 31.35/105 with the standardized rate as 13.72/105.The mortality kept increasing significantly in the population older than 60 years.Mortality of rectal cancer was significantly higher in males than in females (P<0.001).The 5-year survival rates in both colon cancer and rectal cancer patients were 48.88% and 54.16%,respectively.Survivals were significantly higher in those who had received surgical treatments than in those without surgical treatments (colon cancer:58.10% vs.37.22%,P<0.001 ; rectal cancer:66.18% vs.39.37%,P<0.001).Conclusion Age seemed to have contributed to an increased morbidity and mortality of CRC in Yangpu district of Shanghai.The mortality of CRC appeared higher than the incidence.Surgical treatment could significantly prolong the survival of CRC patients.
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Objective To discuss the consequences of CT image quality in two different contrast enhancement ways of high pressure syringe. Methods 100 cases by using high-pressure syringes of Lightspeed 16-raw spiral CT and Stellant D-type high-pressure syringe of Medrad, the dose of constrast medium was 4.0 ml/s and the total dose was 80 ml, which was divided into A and B group enhancement scanning. The canalis singularis high pressure syringe was used in 50 cases of A group that no isotonic Na chloride flush, in contrast to 50 samples of B group that were underwent the double isotonic Na chloride flush. The method of evaluation is double-blind observation. Results The number of positive is 40 samples which has radioactive constructed defect in A group. The masculine proportion is 80%. The number of the negative is 10 samples. The proportion is 20%. Correspondingly, the number of radioactive constructed defect in the B group is 24 samples(48%), and the negative number is 26 samples(52%, P