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1.
Nat Med ; 25(9): 1377-1384, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31501601

RESUMO

People living with HIV (PLWH) have expressed concern about the life-long burden and stigma associated with taking pills daily and can experience medication fatigue that might lead to suboptimal treatment adherence and the emergence of drug-resistant viral variants, thereby limiting future treatment options1-3. As such, there is strong interest in long-acting antiretroviral (ARV) agents that can be administered less frequently4. Herein, we report GS-CA1, a new archetypal small-molecule HIV capsid inhibitor with exceptional potency against HIV-2 and all major HIV-1 types, including viral variants resistant to the ARVs currently in clinical use. Mechanism-of-action studies indicate that GS-CA1 binds directly to the HIV-1 capsid and interferes with capsid-mediated nuclear import of viral DNA, HIV particle production and ordered capsid assembly. GS-CA1 selects in vitro for unfit GS-CA1-resistant capsid variants that remain fully susceptible to other classes of ARVs. Its high metabolic stability and low solubility enabled sustained drug release in mice following a single subcutaneous dosing. GS-CA1 showed high antiviral efficacy as a long-acting injectable monotherapy in a humanized mouse model of HIV-1 infection, outperforming long-acting rilpivirine. Collectively, these results demonstrate the potential of ultrapotent capsid inhibitors as new long-acting agents for the treatment of HIV-1 infection.


Assuntos
Proteínas do Capsídeo/antagonistas & inibidores , Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Animais , Fármacos Anti-HIV/farmacologia , Capsídeo/efeitos dos fármacos , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , DNA Viral/efeitos dos fármacos , Preparações de Ação Retardada , Farmacorresistência Viral/efeitos dos fármacos , Infecções por HIV/genética , Infecções por HIV/virologia , HIV-1/genética , HIV-1/patogenicidade , HIV-2/efeitos dos fármacos , HIV-2/patogenicidade , Humanos , Adesão à Medicação , Camundongos
2.
Arch Virol ; 164(12): 3051-3057, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31531743

RESUMO

Infectious myonecrosis virus (IMNV) is one of the most pathogenic viruses that affect Penaeus vannamei shrimp. In 2018, IMNV was reported in grow-out ponds of P. vannamei in Situbondo, Indonesia. Diseased animals displayed clinical signs of infectious myonecrosis (IMN) characterized by white discoloration of skeletal muscle. Histopathology of affected shrimp revealed lesions that are pathognomonic of IMNV infection. The major capsid protein (MCP) gene was amplified and sequenced from representative samples showing IMN pathology. Multiple alignment of predicted amino acid sequences of the MCP gene with known IMNV genotypes in the GenBank database revealed three unique genotypes, SB-A, SB-B and SB-C,in Situbondo samples. The number of amino acid changes in SB-A, SB-B and SB-C compared to known IMNV genotypes ranged from 7-710, including the isolate SB-B, which contains deletion of 622 aa. A phylogenetic analysis using homologous sequences from Brazil and Indonesia showed that these three isolates represent new IMNV genotypes.


Assuntos
Proteínas do Capsídeo/genética , Penaeidae/virologia , Análise de Sequência de DNA/veterinária , Totiviridae/classificação , Animais , Aquicultura , Brasil , Surtos de Doenças , Indonésia , Necrose , Filogenia , Totiviridae/genética
3.
Arch Virol ; 164(12): 3073-3079, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31555902

RESUMO

A canine parvovirus (CPV)-like virus was detected by PCR and isolated from dead coatis in Argentina. Analysis of the full-length genome sequence revealed that it resembled CPV-but also contained a mutation in the VP2 protein (Arg377Ser) that has not been described previously. This is the first report of a CPV-like virus producing clinical disease in coatis. Genetic similarity to CPV-2c viruses detected in Brazil suggests a strong relationship between these viruses. Although the pathogenic potential of CPV- and feline panleukopenia virus (FPV)-like strains in wild animals is still not completely understood, this study highlights the importance of parvoviruses as a threat to wildlife if proper conditions are present.


Assuntos
Proteínas do Capsídeo/genética , Infecções por Parvoviridae/mortalidade , Parvovirus Canino/classificação , Procyonidae/virologia , Animais , Argentina , Brasil , Tamanho do Genoma , Mutação , Infecções por Parvoviridae/veterinária , Parvovirus Canino/genética , Parvovirus Canino/isolamento & purificação , Filogenia , Análise de Sequência de DNA/métodos
4.
Arch Virol ; 164(11): 2849-2852, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31502078

RESUMO

Arracacha virus B type (AVB-T) and oca (AVB-O) strains from arracacha (Arracacia xanthorrhiza) and oca (Oxalis tuberosa) samples collected in 1975 and two additional isolates obtained from arracacha (AVB-PX) and potato (AVB-6A) in Peru in 1976 and 1978, respectively, were studied. In its host responses and serological properties, AVB-PX most resembled AVB-T, whereas AVB-6A most resembled AVB-O. Complete genomic sequences of the RNA-1 and RNA-2 of each isolate were obtained following high-throughput sequencing of RNA extracts from isolates preserved for 38 (AVB-PX) or 32 (the other 3 isolates) years, and compared with a genomic sequence of AVB-O obtained previously (PV-0082). RNA-2 was unexpectedly divergent compared to RNA-1, with the nucleotide (nt) sequence identity of different AVB isolates varying by up to 76% (RNA-2) and 89% (RNA-1). The coat protein amino acid sequences were the most divergent, with AVB-O and AVB-6A having only 68% identity to AVB-T and AVB-PX. Since the RNA2 sequence differences between the two isolate groupings also coincided with host range, symptom, and serological differences, AVB demonstrates considerable intraspecific divergence.


Assuntos
Genoma Viral/genética , RNA Viral/genética , Secoviridae/genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/genética , Sequenciamento de Nucleotídeos em Larga Escala , Magnoliopsida/virologia , Oxalidaceae/virologia , Peru , Doenças das Plantas/virologia , Secoviridae/isolamento & purificação , Solanum tuberosum/virologia
5.
Arch Virol ; 164(11): 2761-2768, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31506786

RESUMO

A multiplex polymerase chain reaction (mPCR) assay was developed to detect and distinguish feline panleukopenia virus (FPV), feline bocavirus (FBoV) and feline astrovirus (FeAstV). Three pairs of primers were designed based on conserved regions in the genomic sequences of the three viruses and were used to specifically amplify targeted fragments of 237 bp from the VP2 gene of FPV, 465 bp from the NP1 gene of FBoV and 645 bp from the RdRp gene of FeAstV. The results showed that this mPCR assay was effective, because it could detect at least 2.25-4.04 × 104 copies of genomic DNA of the three viruses per µl, was highly specific, and had a good broad-spectrum ability to detect different genotypes of the targeted viruses. A total of 197 faecal samples that had been screened previously for FeAstV and FBoV were collected from domestic cats in northeast China and were tested for the three viruses using the newly developed mPCR assay. The total positive rate for these three viruses was 59.89% (118/197). From these samples, DNA from FPV, FBoV and FeAstV was detected in 73, 51 and 46 faecal samples, respectively. The mPCR testing results agreed with the routine PCR results with a coincidence rate of 100%. The results of this study show that this mPCR assay can simultaneously detect and differentiate FPV, FBoV and FeAstV and can be used as an easy, specific and efficient detection tool for clinical diagnosis and epidemiological investigation of these three viruses.


Assuntos
Bocavirus/genética , Proteínas do Capsídeo/genética , Vírus da Panleucopenia Felina/genética , Mamastrovirus/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Animais , Bocavirus/isolamento & purificação , Doenças do Gato/diagnóstico , Doenças do Gato/virologia , Gatos , China , Primers do DNA/genética , Fezes/virologia , Vírus da Panleucopenia Felina/isolamento & purificação , Mamastrovirus/isolamento & purificação , Filogenia , Análise de Sequência de DNA
6.
Arch Virol ; 164(11): 2891-2894, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31506787

RESUMO

Contigs with sequence similarity to potato virus P (PVP), which belongs to the genus Carlavirus, were identified by high-throughput sequencing analysis in potato tubers collected from a farmer's potato production field in Surazhevka, Artyom, Primorskiy Krai (Russia) in 2018. The complete genome sequence of this virus consisted of 8,394 nucleotides, excluding the poly(A) tail. This is the first report of PVP being detected outside South America. The isolate had high sequence similarity to PVP isolates from Argentina and Brazil, but low sequence similarity was observed in the genes encoding the RNA-dependent RNA polymerase (69% nucleotide sequence identity and 80% amino acid sequence identity) and coat protein (78% nucleotide sequence identity and 89% amino acid sequence identity). Phylogenetic analysis revealed that this PVP-like virus clustered with known PVP isolates but was distinct from them. Comparison of the sequences using the classification criteria of the ICTV indicated that this PVP-like virus is a strain of PVP.


Assuntos
Carlavirus/genética , Genoma Viral/genética , Doenças das Plantas/virologia , Solanum tuberosum/virologia , Sequência de Aminoácidos , Proteínas do Capsídeo/genética , Carlavirus/classificação , Carlavirus/isolamento & purificação , RNA Polimerases Dirigidas por DNA/genética , Sequenciamento de Nucleotídeos em Larga Escala , RNA Viral/genética , Federação Russa , Sequenciamento Completo do Genoma
7.
BMC Infect Dis ; 19(1): 696, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31387542

RESUMO

BACKGROUND: Human norovirus is regarded as the leading cause of nonbacterial acute diarrhea in developing and developed countries. Among all genotypes, GII.4 has been the predominant genotype, but in East Asia, it was replaced by the GII.17 in 2014/2015. However, after the prevalence of new GII.17 variant in South China, a sharply increase in the number of norovirus infections associated with sporadic acute diarrhea was detected. In this study, we would investigate the prevalence and genetic diversity of noroviruses in the sporadic acute gastroenteritis cases in the post-GII.17 period in South China. METHODS: Norovirus was screened from 217 patients with sporadic acute gastroenteritis from August 2015 to October 2017 by reverse transcription-polymerase chain reaction. Then, two regions including the partial RNA polymerase and the capsid gene of positive samples were amplified and sequenced. Phylogenetic analyses were performed to determine norovirus genotypes. Complete VP1 sequences of GII.4 strains detected in this study were also amplified and subjected into evolutionary tracing analyses. RESULTS: A total of 43 (19.82%) norovirus samples were confirmed from 217 stool specimens, and it was found that GII.4 resurged as the new predominant variant, accounting for 76.74% (33/43) of positive samples. Only one local strain GZ2015-L550 was clustered with the contemporary GII.P16/GII.4-2012 recombinant variant, and other 32 local strains belonged to the clade with the GII.Pe/GII.4-2012 variant. Other genotypes including GII.17 (n = 4), GII.3 (n = 4), GII.8 (n = 1) and GI. 6 (n = 1) were also detected. Furthermore, all GII.4 strains were phylogenetic analyzed based on their capsid P2 subdomains. Combined with other reported 754 strains, the GII.4-2012 variant could be divided into two clades. Most GII.4 strains collected in 2016 and 2017 in this study (7/8) formed a new cluster A in Clade II with additional 103 contemporaneous strains. In addition, evolutionary tracing of the capsid P2 subdomain of this variant was also analyzed, and one specific amino acid substitutions (N373) was identified for Cluster A. CONCLUSION: In summary, this study confirmed a norovirus infection peak in the post-GII.17 period in South China, which was caused by the resurgence of the GII.4 variant.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Norovirus/genética , Adolescente , Adulto , Substituição de Aminoácidos , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Diarreia/epidemiologia , Diarreia/virologia , Fezes/virologia , Feminino , Variação Genética , Humanos , Masculino , Norovirus/patogenicidade , Filogenia , Prevalência
8.
Arch Virol ; 164(11): 2775-2781, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31401693

RESUMO

Diagnosis and epidemiological analysis of human parvovirus B19 (hB19V) infections are essential for disease management in severely ill patients. This study aimed to evaluate the performance of an optimized NS1-VP1u nested PCR for detection and sequencing of viruses in clinical samples using 224 clinical and five reference samples. PCR sensitivity, specificity, and positive and negative predictive values were perfect (100%). While phylogenetic analysis of a 615 bp-long fragment demonstrated that the viruses in all of the samples belonged to genotype 1, this study confirmed that this optimized PCR could detect all known hB19V with high performance.


Assuntos
Proteínas do Capsídeo/genética , Eritema Infeccioso/diagnóstico , Eritema Infeccioso/epidemiologia , Parvovirus B19 Humano/genética , Proteínas não Estruturais Virais/genética , DNA Viral/genética , Eritema Infeccioso/virologia , Humanos , Filogenia , Reação em Cadeia da Polimerase/métodos
9.
BMC Infect Dis ; 19(1): 736, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31438883

RESUMO

BACKGROUND: Noroviruses (NoVs) are considered an important cause of acute gastroenteritis (AGE) across all age groups, especially in children under 5 years of age. We investigated the epidemiology of noroviruses in outpatient children from the Children's Hospital of Fudan University in Shanghai, China. METHODS: Stool specimens were collected between January 2012 and December 2017 from 1433 children under 5 years of age with acute gastroenteritis. All samples were analysed by conventional reverse transcription-polymerase chain reaction (RT-PCR) for genogroup II NoVs amplifying both the RNA-dependent RNA polymerase (RdRp) and partial capsid genes. The Norovirus Genotyping Tool v.2.0 ( https://www.rivm.nl/mpf/typingtool/norovirus/ ) was used for genotyping the strains, and phylogenetic analyses were conducted by MEGA 6.0. RESULTS: From 2012 to 2017, GII NoVs were detected in 15.4% (220/1433) of the samples, with the highest detection rate in children aged 7-12 months (19.2%, 143/746). The seasons with the highest prevalence of GII NoVs infection were autumn and winter. Based on genetic analysis of RdRp, GII.Pe (74.5%%, 137/184) was the most predominant RdRp genotype from 2013 to 2017, while GII.P4 played a dominant role in 2012 (55.6%, 21/36). Among the capsid genotypes, the most prevalent NoV genotype from 2012 to 2017 was GII.4 (74.1%, 163/220). On the basis of genetic analysis of RdRp and capsid sequences, the strains were clustered into - 19 RdRp/capsid genotypes, and 12 of them were discordant, such as GII.Pe/GII.4-Sydney_2012, GII.P12/GII.3, GII.P7/GII.6, GII.Pe/GII.3, and GII.P16/GII.2. Starting with 2013, GII.Pe/GII.4-Sydney_2012 had completely replaced the pandemic GII.P4-2006b/GII.4-2006b subtype and was detected in children across all age groups. CONCLUSIONS: The present study shows high detection rates and the genetic diversity of circulating NoV GII genotypes in paediatric AGE samples from Shanghai. The findings emphasize the importance of continuous molecular surveillance of emerging NoV strains.


Assuntos
Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Gastroenterite/epidemiologia , Gastroenterite/virologia , Variação Genética , Norovirus/classificação , Norovirus/genética , Doença Aguda , Proteínas do Capsídeo/genética , Pré-Escolar , China/epidemiologia , Feminino , Gastroenterite/patologia , Genótipo , Hospitais Pediátricos , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Norovirus/isolamento & purificação , Filogenia , Prevalência , Estações do Ano
10.
Artigo em Inglês | MEDLINE | ID: mdl-31300131

RESUMO

Small peptides require large carriers to stimulate the humoral immune system. The filamentous phages, such as M13, have been proposed as vectors for expressing and carrying these peptides on their capsid surface. M2e 2-9 (SLLTEVET) residues of the transmembrane protein M2 of Influenza A virus are conserved and considered as a suitable target for immunization against a wide range of Influenza A virus strains. Here, M2e (2-9) sequence of Influenza A virus was fused to the N-terminus of the major coat protein gpVIII of M13 phage and was used to immunize broiler chickens. The results showed that the SLLTEVET peptide on the surface of M13 phage was expressed, the hybrid phage was immunogenic and produced specific antibodies against M2e (2-9) in broiler chickens.


Assuntos
Bacteriófago M13/genética , Epitopos/imunologia , Vírus da Influenza A , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/veterinária , Proteínas da Matriz Viral/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/genética , Técnicas de Visualização da Superfície Celular , Galinhas/imunologia , Epitopos/genética , Imunogenicidade da Vacina , Infecções por Orthomyxoviridae/prevenção & controle , Proteínas Recombinantes de Fusão/imunologia , Proteínas da Matriz Viral/genética
11.
Microb Pathog ; 135: 103617, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31283962

RESUMO

The bluegill sunfish, Lepomis macrochirus, is an important aquacultural and recreational species in southern China because of its excellent taste, rapid growth rate, and good looks. At present, few pathogens are known to affect the bluegill sunfish. However, an iridovirus-like disease recently caused heavy losses to the bluegill sunfish aquaculture industry in Guangdong, China. We report that a virus, designated BSMIV-SD-20171020, was isolated from diseased bluegill sunfish in China. The isolate was efficiently propagated in a Chinese perch brain (CPB) cell line. The cytopathic effect was observed, the MCP gene PCR amplified, and the virus observed with electron microscopy. Its viral titer in CPB cells reached 104.13 TCID50 mL-1. The mortality rate was 100% when bluegill sunfish were challenged with BSMIV-SD-20171020 at a dose of 103.13 TCID50/fish. A histopathological examination revealed basophilic hypertrophied cells in the intestine, liver, and spleen. A nucleotide sequence alignment and phylogenetic analysis of the major capsid protein revealed that isolate BSMIV-SD-20171020 is the species Infectious spleen and kidney necrosis virus (ISKNV), in the genus Megalocytivirus.


Assuntos
Infecções por Vírus de DNA/veterinária , Infecções por Vírus de DNA/virologia , Doenças dos Peixes/virologia , Iridoviridae/classificação , Iridoviridae/isolamento & purificação , Perciformes/virologia , Animais , Aquicultura , Encéfalo , Proteínas do Capsídeo/classificação , Proteínas do Capsídeo/genética , Linhagem Celular , China , Infecções por Vírus de DNA/patologia , Doenças dos Peixes/patologia , Peixes , Iridoviridae/genética , Iridoviridae/patogenicidade , Rim/patologia , Rim/virologia , Fígado/patologia , Fígado/virologia , Percas , Filogenia , Análise de Sequência de DNA/veterinária , Baço/patologia , Baço/virologia
12.
BMC Vet Res ; 15(1): 232, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31286975

RESUMO

BACKGROUND: Recently, serotype 4 fowl adenovirus (FAdV-4) has spread widely and caused huge economic loss to poultry industry. However, little is known about the molecular pathogenesis of FAdV-4. Fiber protein is thought to be vital for its infection and pathogenesis. RESULTS: Two novel monoclonal antibodies (mAbs) targeting the fiber-1 protein of FAdV-4 were generated, designated as mAb 3B5 and 6H9 respectively. Indirect immunofluorescence assay (IFA) showed that both mAbs only reacted with the FAdV-4 and FAdV-10, not with other serotypes including FAdV-1, FAdV-5, FAdV-6, FAdV-7, FAdV-8 and FAdV-9 tested. Although both mAbs did not recognize the linear epitopes, they could efficiently immunoprecipitate the fiber-1 protein in LMH cells either infected with FAdV-4 or transfected with pcDNA3.1-Fiber-1. Moreover, mAb 3B5 as a capture antibody and HRP-conjugated mAb 6H9 as a detection antibody, a novel sandwich ELISA for efficient detection of FAdV-4 was generated. The limit of detection of the ELISA could reach to 1000 TCID50/ml of FAdV-4 and the ELISA could be efficiently applied to detect FAdV-4 in the clinical samples. CONCLUSION: The two mAbs specific targeting fiber-1 generated here would pave the way for further studying on the role of fiber-1 in the infection and pathogenesis of FAdV-4, and the established mAb based sandwich ELISA would provide an efficient diagnostics tool for detection of FAdV-4/10.


Assuntos
Infecções por Adenoviridae/diagnóstico , Anticorpos Monoclonais/metabolismo , Aviadenovirus/fisiologia , Proteínas do Capsídeo/imunologia , Doenças das Aves Domésticas/diagnóstico , Infecções por Adenoviridae/virologia , Animais , Anticorpos Antivirais/metabolismo , Aviadenovirus/genética , Proteínas do Capsídeo/genética , Linhagem Celular , Galinhas , Ensaio de Imunoadsorção Enzimática , Técnica Indireta de Fluorescência para Anticorpo , Limite de Detecção , Camundongos Endogâmicos BALB C , Doenças das Aves Domésticas/virologia
13.
Emerg Microbes Infect ; 8(1): 1076-1085, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31339457

RESUMO

Enterovirus A71 (EV-A71) is one of the main causative agents of hand-foot-and-mouth disease and is occasionally associated with severe neurological complications. EV-A71 pathophysiology is poorly understood due to the lack of small animal models that robustly support viral replication in relevant organs/tissues. Here, we show that adult severe combined immune-deficient (SCID) mice can serve as an EV-A71 infection model to study neurotropic determinants and viral tropism. Mice inoculated intraperitoneally with an EV-A71 clinical isolate had an initial infection of the lung compartment, followed by neuroinvasion and infection of (motor)neurons, resulting in slowly progressing paralysis of the limbs. We identified a substitution (V135I) in the capsid protein VP2 as a key requirement for neurotropism. This substitution was also present in a mouse-adapted variant, obtained by passaging the clinical isolate in the brain of one-day-old mice, and induced exclusive neuropathology and rapid paralysis, confirming its role in neurotropism. Finally, we showed that this residue enhances the capacity of EV-A71 to use mouse PSGL1 for viral entry. Our data reveal that EV-A71 initially disseminates to the lung and identify viral and host determinants that define the neurotropic character of EV-A71, pointing to a hitherto understudied role of PSGL1 in EV-A71 tropism and neuropathology.


Assuntos
Proteínas do Capsídeo/genética , Enterovirus Humano A/fisiologia , Infecções por Enterovirus/metabolismo , Glicoproteínas de Membrana/metabolismo , Neurônios/virologia , Animais , Proteínas do Capsídeo/metabolismo , Enterovirus Humano A/genética , Enterovirus Humano A/patogenicidade , Infecções por Enterovirus/genética , Infecções por Enterovirus/virologia , Interações Hospedeiro-Patógeno , Humanos , Glicoproteínas de Membrana/genética , Camundongos , Camundongos SCID , Mutação de Sentido Incorreto , Neurônios/metabolismo , Tropismo Viral , Virulência , Internalização do Vírus
14.
Arch Virol ; 164(10): 2459-2467, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31286220

RESUMO

Tobacco vein banding mosaic virus (TVBMV) is of increasing importance in tobacco production. Knowledge of the genetic structure and variability of the virus population is vital for developing sustainable management. In this study, 24 new TVBMV isolates from Sichuan Province together with 46 previous isolates were studied based on their coat protein sequences. Two distinguishable clades were supported by phylogenetic analysis. The summary statistics PS, AI and MC showed a strong TVBMV-geography association between the isolates from Southwest China (SW) and Mainland China (MC). Further analysis indicated that the spatial genetic structure of TVBMV populations is likely to have been caused by natural selection. Phylogeographic analysis provided strong support for spatial diffusion pathways between the Southwest and Northwest tobacco-producing regions. The TVBMV CP gene was found to be under negative selection, and no significant positive selection of amino acids was detected in the SW group; however, the isolates of the MC group experienced significant positive selection pressure at the first and third amino acid sites of CP. This study suggests that natural selection and habitat heterogeneity are important evolutionary mechanisms affecting the genetic structure of the TVBMV population.


Assuntos
Variação Genética , Doenças das Plantas/virologia , Potyvirus/classificação , Potyvirus/genética , Tabaco/virologia , Proteínas do Capsídeo/genética , China , Filogeografia , Potyvirus/isolamento & purificação , Seleção Genética , Análise de Sequência de DNA
15.
Arch Virol ; 164(10): 2545-2549, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31317260

RESUMO

A novel bisegmented double-stranded RNA virus was identified in the mycoparasitic and opportunistic fungus Hypomyces chrysospermus. The RNA1 genome segment comprises 1866 bp and encodes an RNA-dependent RNA polymerase (RdRp). The RNA2 segment comprises 1822 bp and encodes a capsid protein. Phylogenetic analysis of the RdRp protein indicated that this virus is a new member of genus Alphapartitivirus in the family Partitiviridae. We have designated this mycovirus as "Hypomyces chrysospermus partitivirus 1" (HcPV1). HcPV1 is highly transmissible with aleurioconidia and is present in large amounts within growing mycelium in comparison to the GAPDH reference gene.


Assuntos
Micovírus/classificação , Micovírus/isolamento & purificação , Hypocreales/virologia , Filogenia , Vírus de RNA/classificação , Vírus de RNA/isolamento & purificação , Proteínas do Capsídeo/genética , Micovírus/genética , Genoma Viral , RNA Replicase/genética , Vírus de RNA/genética , Análise de Sequência de DNA
16.
Arch Virol ; 164(10): 2565-2571, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31321585

RESUMO

Enteroviruses (EVs) are the major cause of hand, foot, and mouth disease (HFMD) and herpangina in children. In this study, we conducted a molecular investigation of EVs in throat swab samples from children in Hangzhou, China with a diagnosis of HFMD or herpangina. EVs were detected using one-step real-time RT-PCR, and their serotypes were determined based on partial VP1 gene sequences. The molecular typing results revealed the presence of six different EV serotypes in HFMD cases, including coxsackievirus (CV) A16 (20/30, 66.7%), CVA4 (3/30, 10.0%), CVA6 (3/30, 10.0%), EVA71 (2/30, 6.7%), CVB4 (1/30, 3.3%), and CVB5 (1/30, 3.3%). Eleven different EV serotypes were detected in herpangina cases, among which CVA4 was the most frequently detected serotype (105/170, 61.8%), followed by CVA16 (30/170, 17.6%), CVB4 (9/170, 5.3%), CVA6 (6/170, 3.5%), CVB3 (5/170, 2.9%), CVA10 (3/170, 1.8%), EVA71 (4/170, 2.4%), Echo9 (3/170, 1.8%), CVA9 (2/170, 1.2%), CVB1 (3/170, 1.8%) and CVA5 (1/170, 0.6%). The nucleotide sequence identity of EV strains from the same subtype ranged from 80.7% to 100%, and most of the EVs were closely related to virus strains found in Australia and mainland China. In conclusion, CVA 16 and CVA 4 were the main serotypes causing HFMD and herpangina, respectively, in children in Hangzhou in 2016. Most of these EVs were closely related to virus strains from Australia and mainland China.


Assuntos
Enterovirus/classificação , Enterovirus/isolamento & purificação , Doença de Mão, Pé e Boca/epidemiologia , Doença de Mão, Pé e Boca/virologia , Herpangina/epidemiologia , Herpangina/virologia , Sorogrupo , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , China/epidemiologia , Enterovirus/genética , Enterovirus/imunologia , Feminino , Variação Genética , Humanos , Lactente , Masculino , Epidemiologia Molecular , Tipagem Molecular , Faringe/virologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA
17.
Arch Virol ; 164(10): 2581-2584, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31359148

RESUMO

Maize chlorotic mottle virus (MCMV), an important quarantine virus, causes lethal necrosis in maize when coinfected with a potyvirid, which is seriously threatening the production of maize worldwide. In this study, recombinase polymerase amplification (RPA), a novel isothermal DNA amplification and detection technique, was developed to detect MCMV in maize crops. A pair of specific primers was designed based on the conserved sequences of the MCMV coat protein region. The RT-RPA assay was carried out as an isothermal reaction at 38 °C that was complete within 30 min, and no cross-reactivity was detected with other viruses infecting maize in China. The limit of detection of the RT-RPA assay was tenfold lower than that of ordinary RT-PCR. Moreover, this method was successfully applied to test field-collected samples. The newly developed RT-RPA assay offers a reliable, sensitive and efficient method for rapid detection of MCMV in maize in equipment-limited diagnostic laboratories and on-site facilities.


Assuntos
Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Doenças das Plantas/virologia , Tombusviridae/isolamento & purificação , Proteínas do Capsídeo/genética , China , Primers do DNA/genética , Sensibilidade e Especificidade , Temperatura Ambiente , Fatores de Tempo , Tombusviridae/classificação , Tombusviridae/genética
18.
Arch Virol ; 164(8): 2209-2213, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161389

RESUMO

The complete genome of a double-stranded RNA (dsRNA) mycovirus, Phoma matteuccicola partitivirus 1 (PmPV1) was sequenced. It consists of two dsRNA segments, 1664 bp (dsRNA-1) and 1383 bp (dsRNA-2) in length, each containing a single open reading frame (ORF) potentially encoding a 46.78-kDa protein and a 40.92-kDa protein, respectively. dsRNA-1 encodes a putative polypeptide with a conserved RNA-dependent RNA polymerase (RdRp) domain that shows sequence similarity to the corresponding proteins of partitiviruses. The protein encoded by dsRNA-2 has no significant similarity to the typical coat proteins (CPs) of partitiviruses, but structure analysis nevertheless suggested that it might function as a coat protein. Purified viral particles of PmPV1 were isometric and approximately 29 nm in diameter. Phylogenetic analysis showed that PmPV1 is closely related to members of the genus Gammapartitivirus within the family Partitiviridae but forms a separate branch with Colletotrichum acutatum RNA virus 1 and Ustilaginoidea virens partitivirus 2. This is the first report of the full-length nucleotide sequence of a novel virus of the genus Gammapartitivirus infecting P. matteuccicola strain LG915, the causal agent of leaf blight of Curcuma wenyujin.


Assuntos
Ascomicetos/virologia , Micovírus/genética , Genoma Viral/genética , Sequência de Aminoácidos , Sequência de Bases , Proteínas do Capsídeo/genética , Curcuma/virologia , Genômica/métodos , Fases de Leitura Aberta/genética , Filogenia , Doenças das Plantas/virologia , RNA Replicase/genética , Vírus de RNA/genética , RNA de Cadeia Dupla/genética , RNA Viral/genética , Análise de Sequência de DNA/métodos
19.
J Med Microbiol ; 68(8): 1233-1239, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31215861

RESUMO

PURPOSE: Human bocavirus (HBoV) is a DNA virus that is mostly associated with respiratory infections. However, because it has been found in stool samples, it has been suggested that it may be a causative agent for human enteric conditions. This underpins the continuous search for HBoVs, especially after the introduction of the rotavirus vaccine due to acute gastroenteritis cases related to emergent viruses, as HBoVs are more likely to be found in this post-vaccine scenario. Therefore, the aim of this study is to demonstrate the prevalence of HBoV in children aged less than 10 years with acute gastroenteritis in Brazil from November 2011 to November 2012. METHODOLOGY: Stool samples from hospitalized children ≤10 years old who presented symptoms of acute gastroenteritis were analysed for the presence of rotavirus A (RVA) by an enzyme-linked immunosorbent assay (ELISA), and for HBoV DNA by nested PCR. RESULTS: HBoV positivity was detected in 24.0 % (54/225) of samples. Two peaks of HBoV detection were observed in November 2011 and from July to September 2012. Co-infections between HBoV and rotavirus A were identified in 50.0 % (27/54) of specimens. Phylogenetic analysis identified the presence of HBoV-1 (94.8 %), HBoV-2 (2.6 %) and HBoV-3 (2.6 %) species, with only minor variations among them. CONCLUSION: Our findings provide evidence for the circulation of most HBoV genotypes (except HBoV-4) in the North Region of Brazil at a considerable rate and further investigations are necessary to improve our knowledge in the context of HBoV infections and their role in gastrointestinal diseases.


Assuntos
Gastroenterite/epidemiologia , Bocavirus Humano/genética , Epidemiologia Molecular , Infecções por Parvoviridae/epidemiologia , Doença Aguda , Brasil/epidemiologia , Proteínas do Capsídeo/genética , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/virologia , DNA Viral/genética , Fezes/virologia , Feminino , Gastroenterite/virologia , Genótipo , Bocavirus Humano/classificação , Bocavirus Humano/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Masculino , Infecções por Parvoviridae/virologia , Filogenia , Reação em Cadeia da Polimerase , Prevalência , Rotavirus/imunologia , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/virologia , Análise de Sequência de DNA
20.
J Med Microbiol ; 68(8): 1240-1243, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31237533

RESUMO

The aim of the present study was to report the molecular characterization of human group A rotaviruses (RVAs) circulating in Tunisia. Stool specimens were collected from children under 5 years of age who had been hospitalized or were consulting for gastroenteritis in Tunisian hospitals between 2015 and 2017. All samples were screened by reverse-transcription polymerase chain reaction (RT-PCR) for the detection of the VP6 gene specific for RVA. RVA-positive samples were further analysed for G/P genotyping by semi-nested multiplex RT-PCR. Among 454 tested samples, 72 (15.8 %) were positive for RVA. G1P[8] was the most prevalent detected strain (41.7%), followed by G9P[8] (32.8%), G2P[4] (7.5%), G12P[8] (7.5%), G1P[6] (3.0%), G2P[8] (1.5%) and G3P[8] (1.5%), with mixed infections in 4.5 % of cases. In the absence of a national anti-rotavirus vaccination strategy, RVAs remain the primary aetiological agent for gastroenteritis in Tunisian children.


Assuntos
Gastroenterite/virologia , Infecções por Rotavirus/virologia , Rotavirus/genética , Proteínas do Capsídeo/genética , Pré-Escolar , Fezes/virologia , Gastroenterite/epidemiologia , Variação Genética , Genótipo , Humanos , Lactente , Recém-Nascido , Epidemiologia Molecular , Prevalência , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Estações do Ano , Análise de Sequência de DNA , Tunísia/epidemiologia
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