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The current outbreak of novel coronavirus disease 2019 (COVID-19) is already causing a serious disease burden worldwide, this paper analyzed data of a delta variant Covid-19 outbreak in Hunan, China, and proposed an optimal dose-wise dynamical vaccinating process based on local contact pattern and vaccine coverage that minimize the accumulative cases in a certain future time interval. The optimized result requires an immediate vaccination to that none vaccinated at age group 30 to 39, which is coherent to the prevailing strategies. The dose-wise optimal vaccinating process can be directive for countries or regions where vaccines are not abundant. We recommend that vaccination should be further intensified to increase the coverage of booster shots, thus effectively reducing the spread of COVID-19.
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Objective To analyze the spatial and temporal characteristics of hand, foot and mouth disease (HFMD) in Hunan Province from 2016 to 2020. Methods The data of HFMD in Hunan Province from 2016 to 2020 were collected from China's Disease Prevention and Control Information System. HFMD spatial autocorrelation analysis was conducted by ArcGIS 10.2 software at county level, and spatial-temporal scan statistical analysis was performed by SaTScan 9.7 software. Results A total of 714 157 cases was reported in Hunan Province during 2016-2020, with an average annual incidence rate of 208.36/100 000. Global spatial autocorrelation showed that HFMD had a positive spatial correlation on the county scale in Hunan Province during this period. Local spatial autocorrelation indicated that the hot spots were mainly concentrated in the north of central Hunan, the east of central Hunan and the west of Hunan. Spatial-temporal scanning analysis revealed the first class clusters (RR = 6.65, P< 0.001) covering 34 counties in northern and central Hunan, mainly distributed in Yueyang City, Changsha City, Zhuzhou City, Yiyang City and Xiangtan City from May 2018 to June, and the second class clusters (RR = 3.02, P < 0.001) covering 40 counties in western Hunan and central and southwest Hunan from April 2016 to June 2016. Conclusion HFMD incidence exhibits seasonal and regional characteristics in Hunan Province. The prevention and control of HFMD should be guided by combining the characteristics of spatial-temporal clustering.
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BackgroundSeveral parameters driving the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remain unclear, including age-specific differences in infectivity and susceptibility, and the contribution of inapparent infections to transmission. Robust estimates of key time-to-event distributions remain scarce as well. MethodsWe collected individual records for 1,178 SARS-CoV-2 infected individuals and their 15,648 contacts identified by contact tracing and monitoring over the period from January 13 to April 02, 2020 in Hunan Province, China. We provide descriptive statistics of the characteristics of cases and their close contacts; we fitted distributions to time-to-key-events distributions and infectiousness profile over time; and we used generalized linear mixed model to estimate risk factors for susceptibility and transmissibility of SARS-CoV-2. ResultsWe estimated the mean serial interval at 5.5 days (95%CI -5.0, 19.9) and the mean generation time at 5.5 days (95%CI 1.7, 11.6). The infectiousness was estimated to peak 1.8 days before symptom onset, with 95% of transmission events occurring between 7.6 days before and 7.3 days after the date of symptom onset. The proportion of pre-symptomatic transmission was estimated to be 62.5%. We estimated that at least 3.5% of cases were generated asymptomatic individuals. SARS-CoV-2 transmissibility was not significantly different between working-age adults (15-59 years old) and other age groups (0-14 years old: p-value=0.16; 60 years and over: p-value=0.33), whilst susceptibility to SARS-CoV-2 infection was estimated to increase with age (p-value=0.03). In addition, transmission risk was higher for household contacts (p-value<0.001), decreased for higher generations within a cluster (second generation: odds ratio=0.13, p-value<0.001; generations 3-4: odds ratio=0.05, p-value<0.001, relative to generation 1), and decreased for infectors with a larger number of contacts (p-value=0.04). InterpretationOur findings warn of the possible relevant contribution of children to SARS-CoV-2 transmission. When lockdown interventions are in place, we found that odds of transmission are highest in the household setting but, with the relaxation of interventions, other settings (including schools) could bear a higher risk of transmission. Moreover, the estimated relevant fraction of pre-symptomatic and asymptomatic transmission highlight the importance of large-scale testing, contact tracing activities, and the use of personnel protective equipment during the COVID-19 pandemic.
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Objective@#To make etiological diagnosis and evaluate the protective effects of post-exposure prophylaxis(PEP) in an event of one dog injured seven persons.@*Methods@#Direct immunofluorescence assay (DFA) and nested polymerase chain reaction (PCR) were employed to detect nucleoprotein and nucleoprotein(N) gene of rabies virus in the brain tissues of the dog, the positive samples were sequenced for the full length of N gene of rabies virus, then the homology of the N gene of rabies virus was analyzed after the phylogenetic tree was constructed. Rapid fluorescent focus inhibition test (RFFIT) was applied to detect the rabies virus neutralizing antibodies(RVNA) on day 0, 14 and 40 after PEP.@*Results@#The cerebral, cerebellar and hippocampal tissues were positive by DFA and nested PCR. The phylogenetic tree indicated the rabies virus belonged to the rabies virus genotype I. The homology of the nucleotide and amino acid of the rabies virus N gene were over 86% with the vaccine strains. The titer of the RVNA increased significantly from the day 0 to day 14 after PEP, the lowest was 5.78 IU/ml and the highest was 26.15 IU/ml. On the day 40, the highest RVNA titer was 51.96 IU/ml. No rabies cases occurred in a one year follow-up visit.@*Conclusions@#Normative PEP can effectively prevent the occurrence of rabies cases.
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Objective To improve the diagnostic and therapeutic ability of Brucellosis by analyzing the epidemic and clinical characteristics.Methods A retrospective analysis was done on the data of Brucellosis patients treated in our hospital from 2007 to 2016.Results Since the first case was diagnosed in 2012,27 patients [19 male and 8 female,mean age (44.4 ± 16.9) years] were confirmed by clinical manifestations and positive bacterial cultures results.The annual number of cases from 2012 to 2016 was 1,1,6,4 and 15.Among them,10 cases (37.0%) had a history of close contact with goat,7 cases (25.9%)with raw mutton,1 case (3.7%) with raw beef and 1 case (3.7%) with suspicious laboratory contamination while 8 cases (29.6%) had no evident risk factors for Brucellosis.The common clinical manifestation included fever (81.5%),lumbago/joint pain (55.6%),fatigue (33.3%) and hyperhidrosis (22.2%).The white blood cell count was normal among 20 cases (74.1%) while 6 cases (22.2%) with leukopenia.Mild to moderate anemia in 20 cases (74.1%) and decreased platelet number in 4 case (14.8%).The percentage of elevated alanine aminotransferase,aspartate aminotransferase and lactate dehydrogenase was 32.0%,48.0% and 100%,respectively.Decreased albumin level was found in 23 cases (92.0%).The percentage of elevated erythrocyte sedimentation rate (ESR),C-reactive protein and serum ferritin 75.0%,82.3% and 77.8%,respectively,while 12 cases (85.7%) with procalcitonin level below 0.5 ng/L.According to follow-up for at least half year,all the cases were cured by active medical management.Conclusions The number of Brucellosis cases is rapidly increasing in our hospital.It's of great significance to know the epidemic and clinical characteristics of Brucellosis.
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Objective To analyze the conding region of hantanvirus S gene and predict the structure of nucleoprotein for diagnostic antigen study.Methods RT-PCR was used to amplify the S gene of hantanvirus Hunan03 strain after designing specific primers.The amplification product was cloned into pGM-T vector and then the recombinant vector was transformed into E.coli TOP10,gene sequencing was carried out after blue-white selection and PCR screening for positive clones.The database of NCBI and Swiss-Prot/TrEMBL were used to predict and analyze the structure,biological characteristics and protein structures of S gene.Results The amplification product was about 1290 bp,the pGM-T/S vector was constructed and successfully sequenced,the whole length of the open reading frame (ORF) was composed of 1290 nucleotide residues,among them the GC content was 44.11% and the AT content was 55.89%,it was composed of 429 amino acids (20 kinds),the accession number of the sequence submitted to GenBank was JN712306,its homology of nucleotides to the 76-118 strain was 83% and the homology of amino acids was 98%,ten nonspecific variation sites were found.The grand average of hydropathicity was-0.405.There were three transmembrane domains and four non transmembrane domains in the secondary structure of nucleoprotein including 55% of helix structure,6.1% of sheet structure and 38.9% of loop structure.Conclusion The bioinformatics analysis of Hunan03 strain S gene might be important for provide the substructure data to reveal the significance of S gene characteristics on hemorrhagic fever renal syndrome (HFRS) prevention and control.
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Objective To analyze the prevalence status and the genetic characterizations of influenza B viruses isolated in Hunan Province after pandemic influenza A (H1N1) 2009,and to explore possible reasons for the prevalence.MethodsThroat swabs were collected from outpatients with influenza-like illness in 23 sentinel hospitals of Hunan Province in 2010.Influenza viruses were isolated with Madin-Darby canine kidney (MDCK) cells and identified by haemagglutination inhibition test.The genomes of 10 selected influenza B viruses were sequenced and analyzed for phylogenetic and molecular characterization.ResultsWith the reduction of isolation of pandemic influenza A (H1N1)2009 viruses,influenza B virus became the predominant isolated strain in the first half of 2010.Epidemic viruses mainly belonged to the B/Victoria lineage,and both two lineages co-circulated.Seven out of 11 influenza outbreaks caused by type B.Ten strains were filled into 2 branches of BV and BY which were classified by their lineage types in polymerase (PB2,PB1,PA),hemagglutinin (HA),neuraminidase (NA),NB,membrane protein (M1),influenza B virus membrane protein M2 (BM2),and non-structural protein (NS1,NS2) phylogenetic trees except the NP phylogenetic tree in which 10 strains were all in the BY branch.Compared with World Health Organization (WHO) vaccine strains,the amino acid identity of 11 proteins of the 10 strains was high (97.2%-100.0%).However,some amino acid point mutations were found.No mutation was found in drug resistance mutation sites.Some mutations in NA,NB,PB1,PB2 and NS2 molecules were found in 2 strains isolated from outbreaks compared with strains from sentinel surveillance.Conclusions The point mutations,insertions and genetic reassortment indicate viruses sustaining evolution,which is probably the reason for predominant influenza B viruses after pandemic influenza A (H1N1) 2009 in Hunan Province.
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<p><b>OBJECTIVE</b>To investigate the relationship between the molecular characteristics and phylogenetic evolution of rabies N gene.</p><p><b>METHODS</b>Saliva samples were collected from rabies cases, and RT-PCR was used to amplify the N gene of rabies virus with the specific primers. The amplifying product of RT-PCR was cloned to pUCm-T vector and transformed into E.coli XL1-Blue and then the blue-white selection, PCR screening and gene sequencing were carried out to identify the positive clones. Finally, ExPASy and other bioinformatics software were used to analyze and predict the structure and biological characteristics of the N genome.</p><p><b>RESULTS</b>The amplification product of RT-PCR was 1 353 bp, the recombinant plasmid pUCm-T/N was constructed, the whole length of the N gene open reading frame was composed of 1 353 nucleotide residues to code 450 amino acids (20 kinds), the accession number submitted to the Genbank was HM756692, its sequence homology of nucleotides and amino acids compared with the vaccine strain CTN-1-V was 90% and 99% respectively. The evolutionary analysis showed that the isolated strain belonged to genotype I with certain geographic regionality.</p><p><b>CONCLUSION</b>The characteristics investigation and bioinformatics analysis of Hunan0806 N gene will provide fundamental data to reveal the significance of the N gene characteristics for rabies epidemiology and its prevention & control.</p>
Subject(s)
Humans , Amino Acid Sequence , Gene Expression Regulation, Viral , Physiology , Models, Molecular , Molecular Sequence Data , Nucleocapsid Proteins , Genetics , Metabolism , Phylogeny , Protein Conformation , Rabies , Virology , Rabies virus , Genetics , Metabolism , Saliva , VirologyABSTRACT
Abdominal aortic aneurysms (AAA) is one kind of common vascular disease. Inflammation and matrix degradation in the vasculature are crucial for AAA formation, key mechanism of which include vascular smooth muscle cell(VSMC) senescence, oxidative stress, increased local production of proinflammatory cytokines, and increased activities of matrix metalloproteinase (MMPs). Cyp A, the member of cyclophilins,has a variety of physiological functions. It is highly expressed in VSMC, and plays an important role in the development of AAA, making it a new therapeutic target for such disease.
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Objective To study the feasibility, safety and clinical effects of spleen and splenic vessel-preserving distal pancreatectomy. Methods A retrospective study was performed in 26 patients undergoing distal pancreatectomy for benign or low grade malignant disease with splenectomy (n = 13) or splenic preservation (n = 13 ) at the First Hospital of Sun Yat-sen University and Guangdong General Hospital from May 2002 to April 2009. Results All 26 pancreatectomy with splenectomy or splenic preservation were performed successfully. There was no statistically significant difference between two groups in average operative time[(172±47) min vs. (157±52) min, P > 0.05 ], intraoperative estimated blood loss [( 183 ± 68 ) ml vs. ( 160 ± 51 ) ml, P > 0.05 ], incidence of noninfectious and infection complication and postoperative hospital stay [(10.1±2.2) d vs. ( 12. 1 ± 4. 6 ) d, P > 0.05 ]. The platelet counts examined one week after operation were significantly higher in the distal pancreatectomy with splenectomy group than that in spleen-preserving group [(37.3 ± 12.8)×109/L vs. (54.7 ± 13.2) × 109/L, P<0.05 ]. Conclusions Spleen-preserving distal pancreatectomy appears to be a feasible and safe procedure in selected cases of benign or low-grade pancreatic malignant disease necessitating a distal pancreatectomy.