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Objective@#To investigate the origin of infection and risk factors of a case with SARS-CoV-2 infection associated with overseas countries in the Ningbo-Zhoushan Port, Zhejiang Province, so as to provide the evidence for improving the COVID-19 control measures at ports.@*Methods@#Ningbo Center for Disease Control and Prevention ( CDC ) and Beilun CDC conducted case finding and epidemiological surveys immediately after being informed. The general information, history of vaccination and the travel during the latest 14 days were collected from the positive case, and all close contacts were tracked. Saliva samples were collected for SARS-CoV-2 nucleic acid testing and whole-genome sequencing, and the sequencing results were aligned with the GISAID's EpiCoV database. The origin of infection and transmission route of the positive case was investigated.@*Results@#A case was identified positive for SARS-CoV-2 nucleic acid during company M's routine screening in the Ningbo-Zhoushan Port on August 10, 2021, and was confirmed positive for SARS-CoV-2 nucleic acid by Beilun CDC and Ningbo CDC on August 11. Whole-genome sequencing showed SARS-CoV-2 B.1.617.2 ( Delta ) variant, which shared the highest homology with the virus sequence uploaded by Russia on June, 2021 ( Russia/MOW-RII-MH27356S/2021 ). The case was a bundling worker for overseas container ships, and reported communicated with foreign boatmen and contacted materials without protected interventions on the SINOKOR AKITA Container Ship between August 4 and 5, 2021. This ship anchored at Vladivostok, Russia from July 27 to 29, anchored at Ningbo Harbor on August 4, and departed on August 5. Then, 11 boatmen from this ship were tested positive for SARS-CoV-2 nucleic acid on August 8. One asymptomatic case was reported in this epidemic; 254 close contacts and 617 secondary close contacts were identified, and all were tested negative for SARS-CoV-2 nucleic acid. No new cases with SARS-CoV-2 infections were detected until August 25, 2021, and the emergency response was therefore terminated.@*Conclusions@#The infection was a sporadic COVID-19 epidemic associated with overseas countries, which was caused by Delta variant infection through contacts with foreign boatmen or materials by a bundling worker in Ningbo-Zhoushan Port; fortunately, no epidemic spread occurred. Intensified closed-loop management and increased frequency of SARS-CoV-2 nucleic acid test among high-risk populations, and improving the precision and rapid emergency treatment of COVID-19 epidemics are required for the containment of COVID-19 at ports.
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OBJECTIVE@#To assess the predictive value of myocardial scar mass in malignant ventricular arrhythmia (MVA) after myocardial infarction.@*METHODS@#Thirty myocardial infarction patients with complete electrophysiology and cardiac MRI data admitted from January 2012 to August 2017 were enrolled in the study. According to the results of intracavitary electrophysiological study, MVA developed in 16 patients (MVA group) and not developed in 14 patients (non-MVA group). The qualitative and quantitative analysis of left ventricular ejection fraction (LVFE) and scar mass was performed with CV post-processing software and predictive value of myocardial scar and LVEF for MVA after myocardial infarction was analyzed using ROC curves.@*RESULTS@#LVEF in MVA group was significantly lower than that in non-MVA group, and scar mass in MVA group was significantly higher than that in non-MVA group (all <0.05). Regression analysis showed that LVEF (=1.580) and scar mass (=6.270) were risk factors for MVA after myocardial infarction. For predicting MVA, the area under ROC curve () of LVEF was 0.696 with a sensitivity of 0.786 and the specificity of 0.685; the of the scar mass was 0.839 with a sensitivity was 0.618 and the specificity of 0.929; the of LVEF combined with scar mass was 0.848 with a sensitivity of 0.688 and specificity of 0.857.@*CONCLUSIONS@#Myocardial scar assessed by late gadolinium enhancement MRI is more effective than LVEF in predicting MVA after myocardial infarction.
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Humans , Arrhythmias, Cardiac , Diagnosis , Cicatrix , Diagnostic Imaging , Contrast Media , Gadolinium , Myocardial Infarction , Diagnostic Imaging , Predictive Value of Tests , Ventricular Function, LeftABSTRACT
Objective: To observe the preventive effects of combined application of total coumarin and essential oil of Angelicae Dahuricae Radix on the migraine rats induced by nitroglycerin, and to explore their mechanisms. Methods: A total of 56 Wistar rats were randomly divided into normal control group (saline 0. 1 mL · 10 g 1), migraine model group (saline 0. 1 mL · 10 g 1), total coumarin of Angelicae Dahuricae Radix group (100 mg · kg-1), essential oil of Angelicae Dahuricae Radix group (100 mg · kg-1), and low dose (25 mg · kg-1), middle dose (50 mg · kg-1) and high dose (100 mg · kg-1) of total coumarin and essential oil composition of Angelicae Dahuricae Radix groups (composition groups) (n=8). After continuously intragastric adminstration for 7 d, the rats were injected subcutaneously with nitroglycerin (10 mg · kg-1) for establishing the migraine models. The behavior of the rats were observed, the levels of nitric oxide (NO) in serum and brain tissue of rats, the levels of calcitonin gene related peptide (CGRP) and endothelin (ET) in plasma of the rats in various groups were detected. Results: Compared with normal control group, the frequencies of head shaking, the face shoting times of posterior legs and the scratching times of anterior limbs of the rats in migraine model group were increased (P<0. 05 or P<0. 01), and the levels of NO in serum and brain tissue of the rats were increased (P< 0. 01). Compared with migraine model group, the frequencies of head shaking, the face shoting times of posterior legs and scratching times of anterior limbs of the rats in total coumarin group, essential oil group, and composition groups were decreased (P<0. 05 or P<0. 01), and the levels of NO in serum and brain tissue of the rats were decreased (P<0. 05 or P<0. 01). Compared with migraine model group, the levels of CGRP and ET in plasma of the rats in essential oil group, total coumarin group and middle and high doses of composition groups were decreased (P<0. 05). Conclusion: The composition of two active ingredients of Angelicae Dahuricae Radix, total coumarin and essential oil, has preventive effects in the migraine rats induced by nitroglycerin, and their mechanisms may be related to regulation of the levels and function of vasoactive substances.
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Objective@#To identify immunodominant linear B cell epitopes in neuraminidase of avian influenza virus H7N9.@*Methods@#By using protean algorithms of bioinformatic software DNAStar, antigenicity, hydrophilicity and surface probability of the H7N9 neuraminidase sequence was analyzed and their corresponding average indexes were calculated. Multiple regions containing potential linear B cell epitopes were predicted. Corresponding peptides were synthesized artificially and used in peptide-ELISA individually to check their reactivity to confirmed H7N9 positive human sera, and H7N9 negative human sera was used as control.@*Results@#Seven potential linear B cell epitopes, namely A to G, were predicted according to their relatively strong antigenicity, hydrophilicity and surface probability. All corresponding synthetic peptides reacted strongly with H7N9 positive sera.@*Conclusions@#Immunodominant linear B cell epitopes in neuraminidase of H7N9 were successfully predicted and confirmed. It will facilitate to clarify molecular basis of the antigen specificity and to make respective antibodies.
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Objective To predict and identify liner B-cell epitopes in the hemagglutinin ( HA) of human-infected avian-origin H7N9 influenza virus and analyze the specificity of H7 subtype.Methods Three serum samples collected at different times from the same patient who was confirmed to be infected with H7N9 influenza virus were provided by Shaoxing People’s Hospital, and one serum sample from healthy person was collected as the control.The extracellular region of HA protein was predicted by TMHMM Sever v.2.0.The potential B-cell epitopes were predicted by DNAStar Lasergene’ s Protean, BcePred and ABCpred tools, and the immunogenicity of the predicted B cell antigen epitopes was assessed by indirect enzyme-linked immunosordent assay ( ELISA ) .H7 subtype specificity was analyzed by comparing HA protein amino acid sequence with H7N9 and H1-H16 subtype influenza virus from Genbank using Clustal X 2.1 software, and Cn3D 4.3.1 software was used to detect the distribution and 3D structure of predicted epitopes on the HA protein of H7N9.Results The potential B-cell epitopes may be located in 172-183, 363-380, 452-472 and 491-506 of extracellular N-terminus of HA protein.ELISA showed that four predicted eptiopes specifically reacted with positive serums from patient.Multi-sequence alignment demonstrated that peptide 172-183 and 363-380 had higher H7 subtype specificity compared with amino acid sequences of other subtypes.Moreover, the predicted linear B-cell epitopes all located on the surface of HA protein according to the 3D structure analysis.Conclusion Four potential B-cell epitopes were identified, in which peptide 172-183 and 363-380 have higher H7 subtype specificity, and may be used in the design of epitope-based vaccines and diagnostics tests.
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Objective To identify immunodominant B linear cell epitopes in capsid proteins VP1 to VP3 of Coxsackievirus A16 (CVA16) strain YY157.Methods The protean algorithms of bioinformatic software Lasergene were used to analyze antigenicity, hydrophilicity and surface probability of amino acid sequence of CVA16 capsid proteins VP1 to VP3.Multiple regions containing potential lineal B cell epitopes were predicted and their corresponding average indexes were calculated by BepiPred 1.0 Server.Corresponding peptides were synthesized and examined in peptide-enzyme-linked immunosorbent assay (ELISA) individually to check whether it reacted positively or negatively toward sera from children with confirmed CVA16 infection.Results Totally 21 possible B cell linear epitopes were predicted according to their relatively strong antigenicity, hydrophilicity and surface probability.The corresponding synthetic peptides reacted positively with sera of CVA16-infected children in a varying extent.Conclusion Immunodominant B cell linear epitopes of capsid proteins VP1 to VP3 of CVA16 strain YY157 are successfully predicted and confirmed.
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A total of 100 HIN1 flu real-time-PCR positive throat swabs collected from fever patients in Zhejiang,Hubei and Guangdong between June and November 2009,were provided by local CDC laboratories.After MDCK cell culture,57 Influenza A Pandemic (H1N1) viruses were isolated and submitted for whole genome sequencing.A total of 39 HA sequences,52 NA sequences,36 PB2 sequences,31 PB1 sequences,40 PA sequences,48 NP sequences,51 MP sequences and 36 NS sequences were obtained,including 20 whole genome sequences.Sequence comparison revealed they shared a high degree of homology (96％～99％) with known epidemic strains (A/Califomia/04/2009(H1N1).Phylogenetic analysis showed that although the sequences were highly conserved,they clustered into a small number of groups with only a few distinct strains.Site analysis revealed three substitutions at loop 220 (221-228) of the HA receptor binding site in the 39 HA sequences:A/Hubei/86/2009 PKVRDQEG→PKVRDQEA,A/Zhejiang/08/2009 PKVRDQEG→PKVRDQER,A/Hubei/75/2009PKVRDQEG→PKVRDQGG,the A/Hubei/75/2009 was isolated from an acute case,while the other two were from patients with mild symptoms.Other key sites such as 119,274,292 and 294 amino acids of NA protein,627 of PB2 protein were conserved.Meanwhile,all the M2 protein sequences possessed the Ser32Asn mutation,suggesting that these viruses were resistant to adamantanes.Comparison of these sequences with other H1N1 viruses collected from the NCBI database provides insight into H1N1 transmission and circulation patterns.
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0.05).Conclusion The group of 13 months age of infants were rarely infected influenza virus in the first time exposure at the age of ≤4 months due to maternal antibodies protection.Whenas,the group of 8 months age who were exposed at the age of ≥5 months,were more easier infected the influenza virus than the group of 13 months age in the first time exposure at the age of ≤4 months.