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1.
Front Microbiol ; 12: 732426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34733250

RESUMO

Salmonella spp. is one of the most common foodborne disease-causing pathogens that can cause severe diseases in very low infectious doses. Rapid and sensitive detecting Salmonella spp. is advantageous to the control of its spread. In this study, a conserved short fragment of the Salmonella invA gene was selected and used to design primers and specific crRNA (CRISPR RNA) for establishing a one-tube and two-step reaction system for Salmonella spp. detection, by combining recombinase polymerase amplification (RPA) with CRISPR-Cas13a (Clustered Regularly Interspaced Short Palindromic Repeats associated protein 13a) cleavage. The established one-tube RPA-Cas13a method can complete the detection within 20 min and the two-step RPA-Cas13a method detection time within 45 min. The designed primers were highly specific to Salmonella spp. and had no cross-reaction with the other nine diarrheal bacteria. The one-tube RPA-Cas13a could detect the Salmonella genome with the limit of 102 copies, which was the same as real-time polymerase chain reaction (PCR), but less sensitive than two-step RPA-Cas13a (100 copies). The detection results of one-tube or two-step RPA-Cas13a and real-time PCR were highly consistent in clinical samples. One-tube RPA-Cas13a developed in this study provides a simple, rapid, and specific detection method for Salmonella spp. While two-step assay was more sensitive and suitable for samples at low abundance.

3.
Signal Transduct Target Ther ; 6(1): 165, 2021 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-33895786

RESUMO

The global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires an urgent need to find effective therapeutics for the treatment of coronavirus disease 2019 (COVID-19). In this study, we developed an integrative drug repositioning framework, which fully takes advantage of machine learning and statistical analysis approaches to systematically integrate and mine large-scale knowledge graph, literature and transcriptome data to discover the potential drug candidates against SARS-CoV-2. Our in silico screening followed by wet-lab validation indicated that a poly-ADP-ribose polymerase 1 (PARP1) inhibitor, CVL218, currently in Phase I clinical trial, may be repurposed to treat COVID-19. Our in vitro assays revealed that CVL218 can exhibit effective inhibitory activity against SARS-CoV-2 replication without obvious cytopathic effect. In addition, we showed that CVL218 can interact with the nucleocapsid (N) protein of SARS-CoV-2 and is able to suppress the LPS-induced production of several inflammatory cytokines that are highly relevant to the prevention of immunopathology induced by SARS-CoV-2 infection.


Assuntos
Antivirais/uso terapêutico , COVID-19/tratamento farmacológico , COVID-19/metabolismo , Simulação por Computador , Reposicionamento de Medicamentos , Modelos Biológicos , SARS-CoV-2/metabolismo , Humanos
4.
J Virol ; 95(4)2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33219167

RESUMO

Among seven coronaviruses that infect humans, three (severe acute respiratory syndrome coronavirus [SARS-CoV], Middle East respiratory syndrome coronavirus [MERS-CoV], and the newly identified severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) are associated with a severe, life-threatening respiratory infection and multiorgan failure. We previously proposed that the cationically modified chitosan N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC) is a potent inhibitor of human coronavirus NL63 (HCoV-NL63). Next, we demonstrated the broad-spectrum antiviral activity of the compound, as it inhibited all low-pathogenicity human coronaviruses (HCoV-NL63, HCoV-229E, HCoV-OC43, and HCoV-HKU1). Here, using in vitro and ex vivo models of human airway epithelia, we show that HTCC effectively blocks MERS-CoV and SARS-CoV-2 infection. We also confirmed the mechanism of action for these two viruses, showing that the polymer blocks the virus entry into the host cell by interaction with the S protein.IMPORTANCE The beginning of 2020 brought us information about the novel coronavirus emerging in China. Rapid research resulted in the characterization of the pathogen, which appeared to be a member of the SARS-like cluster, commonly seen in bats. Despite the global and local efforts, the virus escaped the health care measures and rapidly spread in China and later globally, officially causing a pandemic and global crisis in March 2020. At present, different scenarios are being written to contain the virus, but the development of novel anticoronavirals for all highly pathogenic coronaviruses remains the major challenge. Here, we describe the antiviral activity of an HTCC compound, previously developed by us, which may be used as a potential inhibitor of currently circulating highly pathogenic coronaviruses-SARS-CoV-2 and MERS-CoV.


Assuntos
COVID-19/tratamento farmacológico , Quitosana/análogos & derivados , Infecções por Coronavirus/tratamento farmacológico , Coronavírus da Síndrome Respiratória do Oriente Médio/efeitos dos fármacos , Compostos de Amônio Quaternário/farmacologia , SARS-CoV-2/efeitos dos fármacos , Antivirais/farmacologia , COVID-19/epidemiologia , COVID-19/virologia , Quitosana/farmacologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/metabolismo , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Pandemias , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/virologia , SARS-CoV-2/metabolismo , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos
5.
Virus Res ; 292: 198245, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33253716

RESUMO

Enterovirus A71 (EV-A71) emerged as a leading cause of virus derived infant encephalitis in most Asian countries. Some recent studies point out the critical role of microRNA (miRNA) in the regulation of pyroptosis. However, the role of miRNAs in the regulation of EV-A71 infection-induced pyroptosis was not previously explored. In this study, we utilized microRNA array and real-time PCR to verify that miR-195 significantly down-regulate in EV-A71-infected SH-SY5Y human neuroblastoma cells. An inverse correlation of NLRX1 with miR-195 expression in EV-A71-infected SH-SY5Y cells was found. Target prediction of miR-195 showed that NLRX1 could directly interact with miR-195. Results from luciferase reporter assays, qRT-PCR and western blotting demonstrated the negative regulation between miR-195 and NLRX1. Silencing NLRX1 expression with small interfering RNAs (siRNAs-NLRX1) and over-expression of miR-195 also attenuate the EV-A71 associated pyroptosis. Our findings provided evidence showed that miR-195 can regulate EV-A71 infection-induced pyroptosis, by directly targeting NLRX1.


Assuntos
Enterovirus Humano A/fisiologia , Infecções por Enterovirus/genética , Infecções por Enterovirus/virologia , MicroRNAs/metabolismo , Proteínas Mitocondriais/metabolismo , Neuroblastoma/genética , Piroptose , Linhagem Celular Tumoral , Regulação para Baixo , Enterovirus Humano A/genética , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/fisiopatologia , Regulação da Expressão Gênica , Humanos , MicroRNAs/genética , Proteínas Mitocondriais/genética , Neuroblastoma/metabolismo , Neuroblastoma/virologia
6.
Sci Total Environ ; 753: 141710, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32891988

RESUMO

Respiratory and fecal aerosols play confirmed and suspected roles, respectively, in transmitting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). An extensive environmental sampling campaign of both toilet and non-toilet environments was performed in a dedicated hospital building for patients with coronavirus disease 2019 (COVID-19), and the associated environmental factors were analyzed. In total, 107 surface samples, 46 air samples, two exhaled condensate samples, and two expired air samples were collected within and beyond four three-bed isolation rooms. The data of the COVID-19 patients were collected. The building environmental design and the cleaning routines were reviewed. Field measurements of airflow and CO2 concentrations were conducted. The 107 surface samples comprised 37 from toilets, 34 from other surfaces in isolation rooms, and 36 from other surfaces outside the isolation rooms in the hospital. Four of these samples were positive, namely two ward door handles, one bathroom toilet seat cover, and one bathroom door handle. Three were weakly positive, namely one bathroom toilet seat, one bathroom washbasin tap lever, and one bathroom ceiling exhaust louver. Of the 46 air samples, one collected from a corridor was weakly positive. The two exhaled condensate samples and the two expired air samples were negative. The fecal-derived aerosols in patients' toilets contained most of the detected SARS-CoV-2 in the hospital, highlighting the importance of surface and hand hygiene for intervention.


Assuntos
Aparelho Sanitário , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Síndrome Respiratória Aguda Grave , Betacoronavirus , COVID-19 , Hospitais , Humanos , SARS-CoV-2
7.
Nat Commun ; 11(1): 4421, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887891

RESUMO

Receptor usage that determines cell tropism and drives viral classification closely correlates with the virus structure. Enterovirus B (EV-B) consists of several subgroups according to receptor usage, among which echovirus 30 (E30), a leading causative agent for human aseptic meningitis, utilizes FcRn as an uncoating receptor. However, receptors for many EVs remain unknown. Here we analyzed the atomic structures of E30 mature virion, empty- and A-particles, which reveals serotype-specific epitopes and striking conformational differences between the subgroups within EV-Bs. Of these, the VP1 BC loop markedly distinguishes E30 from other EV-Bs, indicative of a role as a structural marker for EV-B. By obtaining cryo-electron microscopy structures of E30 in complex with its receptor FcRn and CD55 and comparing its homologs, we deciphered the underlying molecular basis for receptor recognition. Together with experimentally derived viral receptor identifications, we developed a structure-based in silico algorithm to inform a rational prediction for EV receptor usage.


Assuntos
Complexo Antígeno-Anticorpo/ultraestrutura , Enterovirus Humano B/ultraestrutura , Antígenos Virais/ultraestrutura , Antígenos CD55/imunologia , Microscopia Crioeletrônica , Enterovirus Humano B/imunologia , Epitopos/ultraestrutura , Humanos , Receptores Fc/imunologia , Vírion/ultraestrutura
8.
Nat Commun ; 11(1): 4419, 2020 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-32887892

RESUMO

Echovirus 30 (E30), a serotype of Enterovirus B (EV-B), recently emerged as a major causative agent of aseptic meningitis worldwide. E30 is particularly devastating in the neonatal population and currently no vaccine or antiviral therapy is available. Here we characterize two highly potent E30-specific monoclonal antibodies, 6C5 and 4B10, which efficiently block binding of the virus to its attachment receptor CD55 and uncoating receptor FcRn. Combinations of 6C5 and 4B10 augment the sum of their individual anti-viral activities. High-resolution structures of E30-6C5-Fab and E30-4B10-Fab define the location and nature of epitopes targeted by the antibodies. 6C5 and 4B10 engage the capsid loci at the north rim of the canyon and in-canyon, respectively. Notably, these regions exhibit antigenic variability across EV-Bs, highlighting challenges in development of broad-spectrum antibodies. Our structures of these neutralizing antibodies of E30 are instructive for development of vaccines and therapeutics against EV-B infections.


Assuntos
Anticorpos Neutralizantes/ultraestrutura , Complexo Antígeno-Anticorpo/ultraestrutura , Proteínas do Capsídeo/imunologia , Enterovirus Humano B/imunologia , Animais , Anticorpos Monoclonais/ultraestrutura , Antígenos Virais , Antígenos CD55/imunologia , Microscopia Crioeletrônica , Epitopos/ultraestrutura , Humanos , Meningite Asséptica/virologia , Camundongos , Receptores Fc/imunologia , Sorogrupo
9.
Virology ; 549: 1-4, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32758712

RESUMO

The current outbreak of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was reported in China firstly. A rapid, highly sensitive, specific, and simple operational method was needed for the detection of SARS-CoV-2. Here, we established a real-time reverse-transcription recombinase-aided amplification assay (RT-RAA) to detect SARS-CoV-2 rapidly. The primers and probe were designed based on the nucleocapsid protein gene (N gene) sequence of SARS-CoV-2. The detection limit was 10 copies per reaction in this assay, which could be conducted within 15 min at a constant temperature (39 °C), without any cross-reactions with other respiratory tract pathogens, such as other coronaviruses. Furthermore, compared with commercial real-time RT-PCR assay, it showed a kappa value of 0.959 (p < 0.001) from 150 clinical specimens. These results indicated that this real-time RT-RAA assay may be a valuable tool for detecting SARS-CoV-2.


Assuntos
Betacoronavirus/genética , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/virologia , Genes Virais , Técnicas de Amplificação de Ácido Nucleico/métodos , Proteínas do Nucleocapsídeo/genética , Pneumonia Viral/virologia , Betacoronavirus/isolamento & purificação , COVID-19 , Teste para COVID-19 , Vacinas contra COVID-19 , China/epidemiologia , Técnicas de Laboratório Clínico/estatística & dados numéricos , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Proteínas do Nucleocapsídeo de Coronavírus , Humanos , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico/estatística & dados numéricos , Pandemias , Fosfoproteínas , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , RNA Viral/análise , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase em Tempo Real/estatística & dados numéricos , Recombinases , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/estatística & dados numéricos , SARS-CoV-2 , Sensibilidade e Especificidade
10.
J Infect Dis ; 222(5): 746-754, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32563194

RESUMO

Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We investigated the serum cytokine and chemokine levels in asymptomatic, mild, moderate, severe, and convalescent SARS-CoV-2-infected cases. Proinflammatory cytokine and chemokine production induced by SARS-CoV-2 were observed not only in symptomatic patients but also in asymptomatic cases, and returned to normal after recovery. IL-6, IL-7, IL-10, IL-18, G-CSF, M-CSF, MCP-1, MCP-3, IP-10, MIG, and MIP-1α were found to be associated with the severity of COVID-19. Moreover, a set of cytokine and chemokine profiles were significantly higher in SARS-CoV-2-infected male than female patients. The serum levels of MCP-1, G-CSF, and VEGF were weakly and positively correlated with viral titers. We suggest that combinatorial analysis of serum cytokines and chemokines with clinical classification may contribute to evaluation of the severity of COVID-19 and optimize the therapeutic strategies.


Assuntos
Quimiocinas/sangue , Infecções por Coronavirus/sangue , Citocinas/sangue , Pneumonia Viral/sangue , Adulto , Betacoronavirus/isolamento & purificação , COVID-19 , Quimiocina CCL2/sangue , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Feminino , Fator Estimulador de Colônias de Granulócitos/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , SARS-CoV-2 , Índice de Gravidade de Doença , Fator A de Crescimento do Endotélio Vascular/sangue , Carga Viral
11.
Virus Res ; 285: 198005, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32408156

RESUMO

Accumulating evidence shows that microbial co-infection increases the risk of disease severity in humans. There have been few studies about SARS-CoV-2 co-infection with other pathogens. In this retrospective study, 257 laboratory-confirmed COVID-19 patients in Jiangsu Province were enrolled from January 22 to February 2, 2020. They were re-confirmed by real-time RT-PCR and tested for 39 respiratory pathogens. In total, 24 respiratory pathogens were found among the patients, and 242 (94.2 %) patients were co-infected with one or more pathogens. Bacterial co-infections were dominant in all COVID-19 patients, Streptococcus pneumoniae was the most common, followed by Klebsiella pneumoniae and Haemophilus influenzae. The highest and lowest rates of co-infections were found in patients aged 15-44 and below 15, respectively. Most co-infections occurred within 1-4 days of onset of COVID-19 disease. In addition, the proportion of viral co-infections, fungal co-infections and bacterial-fungal co-infections were the highest severe COVID-19 cases. These results will provide a helpful reference for diagnosis and clinical treatment of COVID-19 patients.


Assuntos
Infecções Bacterianas/complicações , Betacoronavirus , Coinfecção , Infecções por Coronavirus/complicações , Micoses/complicações , Pneumonia Viral/complicações , Viroses/complicações , Adolescente , Adulto , Fatores Etários , Idoso , COVID-19 , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Estudos Retrospectivos , SARS-CoV-2 , Fatores de Tempo , Adulto Jovem
12.
Virology ; 546: 122-126, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452410

RESUMO

Since SARS-CoV-2 spreads rapidly around the world, data have been needed on the natural fluctuation of viral load and clinical indicators associated with it. We measured and compared viral loads of SARS-CoV-2 from pharyngeal swab, IgM anti-SARS-CoV-2, CRP and SAA from serum of 114 COVID-19 patients on admission. Positive rates of IgM anti-SARS-CoV-2, CRP and SAA were 80.7%, 36% and 75.4% respectively. Among IgM-positive patients, viral loads showed different trends among cases with different severity, While viral loads of IgM-negative patients tended to increase along with the time after onset. As the worsening of severity, the positive rates of CRP and SAA also showed trends of increase. Different CRP/SAA type showed associations with viral loads in patients in different severity and different time after onset. Combination of the IgM and CRP/SAA with time after onset and severity may give suggestions on the viral load and condition judgment of COVID-19 patients.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Coronavirus/diagnóstico , Imunoglobulina M/sangue , Pneumonia Viral/diagnóstico , Carga Viral , Adolescente , Adulto , Idoso , Betacoronavirus , Biomarcadores/sangue , Proteína C-Reativa/análise , COVID-19 , Criança , Infecções por Coronavirus/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pandemias , Faringe/virologia , Pneumonia Viral/sangue , SARS-CoV-2 , Proteína Amiloide A Sérica/análise , Adulto Jovem
13.
Environ Microbiol ; 22(10): 4314-4322, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32319181

RESUMO

Vibrio cholerae can enter a viable but non-culturable (VBNC) state when it encounters unfavourable environments; VBNC cells serve as important reservoirs and still pose threats to public health. The genetic regulation of V. cholerae entering its VBNC state is not well understood. Here, we show a confrontation strategy adapted by V. cholerae O1 in which it utilizes a quorum sensing (QS) system to prevent transition into a VBNC state under low nutrition and temperature conditions. The upregulation of hapR resulted in a prolonged culturable state of V. cholerae in artificial sea water at 4°C, whereas the mutation of hapR led to fast entry into the VBNC state. We also observed that different V. cholerae O1 natural isolates with distinct QS functions present a variety of abilities to maintain culturability during the transition to a VBNC state. The strain groups with higher or constitutive expression of QS genes exhibit a greater tendency to maintain the culturable state during VBNC induction than those lacking QS functional groups. In summary, HapR-mediated QS regulation is associated with the transition to the VBNC state in V. cholerae. HapR expression causes V. cholerae to resist VBNC induction and become dominant over competitors in changing environments.


Assuntos
Percepção de Quorum/genética , Percepção de Quorum/fisiologia , Fatores de Transcrição/metabolismo , Vibrio cholerae O1/genética , Vibrio cholerae O1/metabolismo , Linhagem Celular , Água do Mar , Temperatura , Regulação para Cima , Vibrio cholerae O1/crescimento & desenvolvimento , Vibrio cholerae O1/isolamento & purificação
14.
Virology ; 536: 58-67, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31400550

RESUMO

Human infection with H7N9 virus has provoked global public health concern due to the substantial morbidity and mortality. Neuraminidase inhibitors (NAIs) are used as first-line drugs to treat the infection. However, virus quasispecies can evolve rapidly under drug pressure, which may alter various biological characteristics of virus. Using an in vitro evolution platform and next-generation sequencing, we found the presence of peramivir led to changes to the dominant populations of the virus. Two important amino acid substitutions were identified in NA, I222T and H274Y, which caused reduced susceptibilities to oseltamivir or both oseltamivir and peramivir as confirmed by enzyme- and cell-based assays. The NA-H274Y variant showed decreased replicative fitness at the early stage of infection accompanied with impaired NA function. The quasispecies evolution of H7N9 virus and the potential emergence of these two variants should be closely monitored, which may guide the adjustment of antiviral strategies.


Assuntos
Antivirais/farmacologia , Ciclopentanos/farmacologia , Farmacorresistência Viral/genética , Guanidinas/farmacologia , Subtipo H7N9 do Vírus da Influenza A/efeitos dos fármacos , Neuraminidase/genética , Proteínas Virais/genética , Ácidos Carbocíclicos , Substituição de Aminoácidos , Animais , Cães , Evolução Molecular , Expressão Gênica , Humanos , Subtipo H7N9 do Vírus da Influenza A/enzimologia , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/crescimento & desenvolvimento , Influenza Humana/virologia , Células Madin Darby de Rim Canino , Neuraminidase/metabolismo , Oseltamivir/farmacologia , Carga Viral/efeitos dos fármacos , Proteínas Virais/metabolismo , Replicação Viral/efeitos dos fármacos
15.
Open Forum Infect Dis ; 6(6): ofz209, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31211156

RESUMO

Background: Severe fever with thrombocytopenia syndrome (SFTS) is a typical tick-borne, natural focal disease. The natural foci of SFTS were considered to exist in hilly and mountainous areas before 2015. A cluster of 3 patients exposed to a patient with a fulminant disease consistent with SFTS occurred from July to August 2015 in Dongtai County, which is characterized by alluvial plains; this prompted investigation. Methods: The epidemiological, clinical, and laboratory features of 4 patients in the cluster were analyzed. Serum samples from the indigenous healthy population and native domesticated animals were collected to conduct laboratory tests, along with small wild animals and ticks. Results: In 3 secondary case patients, high fever, thrombocytopenia and leukopenia developed within 8-13 days after contact with blood or bloody secretions from the index patient; SFTS was then diagnosed by means of reverse-transcription polymerase chain reaction. Genomic sequencing and analysis of S and L segments of 2 viral strains isolated from 2 secondary case patients showed that they shared 99.8%-99.9% homology in nucleotide sequence. The seroprevalences among indigenous healthy population, native livestock, native poultry, and small wild animals was 0.74%, 17.54%, 6.67%, and 1.12%, respectively. Three questing ticks, 61 feeding ticks, and 178 small wild animals were collected in August 2015. Survey on tick density and seasonal fluctuation in 2016 showed that ticks were active from March to October. All ticks were identified as Haemaphysalis longicornis. Severe fever with thrombocytopenia bunyavirus (SFTSV)-specific RNA was detected in the ticks collected in 2016, and the minimum SFTSV infection rate in these ticks was 0.54% (1 of 185).Wild mammals and ticks collected in August 2015 tested negative for SFTSV-specific RNA. Conclusions: Aside from hilly or mountainous area, a coastal plain was identified as the natural foci of SFTSV in Dongtai County, China. The involvement of migration in the evolution of SFTSV might lead to a transregional transmission event of SFTSV.

16.
Emerg Infect Dis ; 25(6): 1192-1195, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31107220

RESUMO

Human infections with vaccinia virus (VACV), mostly from laboratory accidents or contact with infected animals, have occurred since smallpox was eradicated in 1980. No recent cases have been reported in China. We report on an outbreak of VACV from occupational exposure to rabbit skins inoculated with VACV.


Assuntos
Surtos de Doenças , Exposição Ocupacional , Vírus Vaccinia , Vaccinia/epidemiologia , Vaccinia/virologia , Acidentes de Trabalho , Adulto , Animais , China/epidemiologia , Genes Virais , História do Século XXI , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Coelhos , Vaccinia/história , Vaccinia/transmissão , Vírus Vaccinia/classificação , Vírus Vaccinia/genética , Adulto Jovem
17.
J Biomed Nanotechnol ; 15(4): 790-798, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30841971

RESUMO

It is urgent to find an avian influenza A H7N9 detection simple method which is suitable for on-site detection. The Cas13a protein just likes a nanomachine, when specifically bound to target RNA by single-stranded RNA (crRNA), changes its protein structure and produces RNase activity, which degrades RNA non-specifically. Harnessing Cas13a, the paper aims to establish an underlying on-site H7N9 virus nucleic acid detection method. LwCas13a protein nanomachine was expressed in a prokaryotic expression system and purified by nickel column. In vitro transcribed RNA of H7N9 HA gene has been used as a target, to design a specific crRNA. The activity of Cas13a was verified with a single-stranded RNA-bound fluorescent group and a quenching fluorophore as signals. Using Cas13a, a room temperature H7N9 detection system was established. Detection of 1 nm of single-stranded RNA can be done within 5 min. When combined with the RT-RPA and T7 transcription system at room temperature, the detection limits of HA and NA are 1 fM and the reaction time is 50 min. Excellent specificity was achieved by comparison with subtype viruses such as H1N1 and H5N1. The rapid detection method based on CRISPR-Cas13a nanomachine H7N9 has been successfully established, which can detect H7N9 quickly and specifically. In the future, it can be quickly detected in the field with portable fluorescence detector.


Assuntos
Subtipo H7N9 do Vírus da Influenza A , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1
18.
BMC Microbiol ; 19(1): 8, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30621594

RESUMO

BACKGROUND: As an important component of the causative agent of respiratory tract infections, enteric and eye infections, Human mastadenoviruses (HAdVs) species B spread easily in the crowd. In this study, we developed a recombinase polymerase amplification (RPA) assay for rapidly detecting HAdVs species B which was comprised of two different formats (real-time and lateral-flow device). RESULTS: This assay was confirmed to be able to detect 5 different HAdVs species B subtypes (HAdV-B3, HAdV-B7, HAdV-B11, HAdV-B14 and HAdV-B55) without cross-reactions with other subtypes and other respiratory tract pathogens. This RPA assay has not only highly sensitivity with low detection limit of 50 copies per reaction but also short reaction time (< 15 min per detection). Furthermore, the real-time RPA assay has excellent correlation with real-time PCR assay for detection of HAdVs species B presented in clinical samples. CONCLUSIONS: Thus, the RPA assay developed in this study provides an effective and portable approach for the rapid detection of HAdVs species B.


Assuntos
DNA Polimerase Dirigida por DNA/metabolismo , Mastadenovirus/classificação , Mastadenovirus/genética , Tipagem Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/normas , Recombinases/metabolismo , Virologia/métodos , Humanos , Limite de Detecção , Reação em Cadeia da Polimerase/normas , Reprodutibilidade dos Testes
19.
Emerg Microbes Infect ; 7(1): 156, 2018 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-30228261

RESUMO

Avian influenza H7N9 viruses are an important public health concern due to their high mortality rate and potentials for future pandemics. We investigated human susceptibility to H7N9 viruses using recombinant H7N9 hemagglutinin (HA) proteins as a probe and found a strong association between H7N9 infections and HA binding among saliva samples from 32 patients and 60 uninfected controls in Jiangsu province, China, during the 2016 epidemic season. We also found that sialyl Lex (SLex) antigen that was recognized by H7N9 HA was associated with H7N9 virus infection. Further analysis suggested that additional saccharide residues adjacent to the SLex moiety may affect the H7N9-binding specificity. Our data suggested that saliva may be a useful reagent to study human susceptibility to avian influenza H7N9 virus, which may impact the disease control and prevention of avian influenza viruses as important human pathogens.


Assuntos
Subtipo H7N9 do Vírus da Influenza A/fisiologia , Influenza Humana/virologia , Saliva/virologia , Adulto , Animais , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Subtipo H7N9 do Vírus da Influenza A/genética , Subtipo H7N9 do Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Masculino , Saliva/imunologia
20.
Virology ; 521: 69-76, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29886343

RESUMO

Enterovirus A71 (EV-A71) infection can cause hand, foot and mouth disease (HFMD), and even fatal meningoencephalitis. Unfortunately, there is currently no effective treatment for EV-A71 infection due to the lack of understanding of the mechanism of neurological diseases. In this study, we employed SH-SY5Y human neuroblastoma cells to explore the roles of caspase-1 in neuropathogenesis. The expression and activity of caspase-1 were analyzed. The potential immuneconsequences mediated by caspase-1 including cell death, lysis, DNA degradation, and secretion of pro-inflammatory were also examined. We found the gene expression levels of caspase-1, IL-1ß, IL-18 and active caspase-1 were markedly increased in the SH-SY5Y cells at 48 h post EV-A71 infection. The cell death, lysis, and DNA degradation were also increased during infection, which could be significantly alleviated by caspase-1 inhibition. These observations provided additional experimental evidence supporting caspase-1-mediated pyroptosis as a novel pathway of inflammatory programmed cell death.


Assuntos
Caspase 1/metabolismo , Enterovirus Humano A/patogenicidade , Doença de Mão, Pé e Boca/patologia , Piroptose , Células Cultivadas , Fragmentação do DNA , Humanos , Inflamação , Interleucina-18/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Neuroblastoma/patologia , Neuroblastoma/virologia , Replicação Viral
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