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1.
Parasite ; 26: 62, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31670656

RESUMO

Enterocytozoon bieneusi is an important pathogen commonly found in humans and animals. Farmed animals with close contact to humans are important hosts of E. bieneusi. The role of goats in the transmission of E. bieneusi, however, remains unclear. In this study, 341 fresh fecal samples of black goats were collected from five locations in Hainan Province, China. Enterocytozoon bieneusi was identified and genotyped by sequences of the internal transcribed spacer (ITS) region. Phylogenetic analysis was performed by constructing a neighbor-joining tree of the ITS gene sequences. The average prevalence of E. bieneusi in black goats was 24.0% (82/341) with rates ranging from 6.3% (4/63) to 37.2% (32/86) across the locations (χ2 = 17.252, p < 0.01). Eight genotypes of E. bieneusi were identified, including six known genotypes: CHG5 (n = 47); CHG3 (n = 23); CHG2 (n = 4); CM21 (n = 3); D (n = 2); and AHG1 (n = 1), and two novel genotypes termed HNG-I (n = 1) and HNG-II (n = 1). In the phylogenetic tree, genotype D was clustered into Group 1 and the other identified genotypes were included in Group 2. This represents the first report identifying E. bieneusi in black goats from Hainan Province, with a high prevalence and wide occurrence demonstrated. The two new genotypes identified provide additional insights into the genotypic variations in E. bieneusi. Due to the small percentage of zoonotic genotypes in these animals, there is minimal risk of zoonotic transmission of E. bieneusi.

2.
Virus Genes ; 55(4): 550-556, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31161411

RESUMO

Japanese encephalitis virus SA14-14-2 (JEV SA14-14-2) is a widely used vaccine in China and other southeastern countries to prevent Japanese encephalitis in children. In this study, a stable infectious cDNA clone of JEV SA14-14-2 with a low copy number pACYC177 vector dependent on the T7 promoter and T7 terminator was developed. Two introns were inserted into the capsid gene and envelope gene of JEV cDNA for gene stability. Hepatitis delta virus ribozyme (HDVr) was engineered into the 3' UTR cDNA of JEV for authentic 3' UTR transcription. The rescued virus showed biological properties indistinguishable from those of the parent strain (JEV SA14-14-2). The establishment of a JEV SA14-14-2 reverse genetics system lays the foundation for the further development of other flavivirus vaccines and viral pathogenesis studies.

3.
Microb Pathog ; 121: 252-261, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29772263

RESUMO

MicroRNAs, a class of noncoding RNAs 18 to 23 nucleotides (nt) in length, play critical roles in a wide variety of biological processes. The objective of this study was to examine differences in microRNA expression profiles derived from the lungs of beagle dogs infected with the avian-origin H3N2 canine influenza virus (CIV) or the highly pathogenic avian influenza (HPAI) H5N1 virus (canine-origin isolation strain). After dogs were infected with H3N2 or H5N1, microRNA expression in the lungs was assessed using a deep-sequencing approach. To identify the roles of microRNAs in viral pathogenicity and the host immune response, microRNA target genes were predicted, and their functions were analyzed using bioinformatics software. A total of 229 microRNAs were upregulated in the H5N1 infection group compared with those in the H3N2 infection group, and 166 microRNAs were downregulated. MicroRNA target genes in the H5N1 group were more significantly involved in metabolic pathways, such as glycerolipid metabolism and glycerophospholipid metabolism, than those in the H3N2 group. The inhibition of metabolic pathways may lead to appetite loss, weight loss and weakened immunity. Moreover, miR-485, miR-144, miR-133b, miR-4859-5p, miR-6902-3p, miR-7638, miR-1307-3p and miR-1346 were significantly altered microRNAs that potentially led to the inhibition of innate immune pathways and the heightened pathogenicity of H5N1 compared with that of H3N2 in dogs. This study deepens our understanding of the complex relationships among microRNAs, the influenza virus-mediated immune response and immune injury in dogs.

4.
Dev Comp Immunol ; 74: 60-68, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28395999

RESUMO

Despite the apparent lack of a feline influenza virus lineage, cats are susceptible to infection by influenza A viruses. Here, we characterized in vitro A/feline/Guangdong/1/2015, an H5N6 avian influenza virus recently isolated from cats. A/feline/Guangdong/1/2015 replicated to high titers and caused CPE in feline kidney cells. We determined that infection with A/feline/Guangdong/1/2015 did not activate the IFN-ß promoter, but inhibited it by blocking the activation of NF-κB and IRF3. We also determined that the viral NS1 protein mediated the block, and that the dsRNA binding domain of NS1 was essential to perform this function. In contrast to treatment after infection, cells pretreated with IFN-ß suppressed viral replication. Our findings provide an example of an H5N6 influenza virus suppressing IFN production, which might be associated with interspecies transmission of avian influenza viruses to cats.


Assuntos
Vírus da Influenza A/fisiologia , Interferon beta/metabolismo , Infecções por Orthomyxoviridae/imunologia , Proteínas não Estruturais Virais/metabolismo , Animais , Gatos , Células Cultivadas , Evasão da Resposta Imune , Fator Regulador 3 de Interferon/metabolismo , Interferon beta/genética , NF-kappa B/metabolismo , Transdução de Sinais , Replicação Viral
6.
Front Immunol ; 7: 377, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27708647

RESUMO

Mitochondrial antiviral-signaling protein (MAVS), an adaptor protein of retinoic acid-inducible gene I (RIG-I)-like receptors (RLRs)-mediated signal pathway, is involved in innate immunity. In this study, Cherry Valley duck MAVS (duMAVS) was cloned from the spleen and analyzed. duMAVS was determined to have a caspase activation and recruitment domain at N-terminal, followed by a proline-rich domain and a transmembrane domain at C-terminal. Quantitative real-time PCR indicated that duMAVS was expressed in all tissues tested across a broad expression spectrum. The expression of duMAVS was significantly upregulated after infection with duck Tembusu virus (DTMUV). Overexpression of duMAVS could drive the activation of interferon (IFN)-ß, nuclear factor-κB, interferon regulatory factor 7, and many downstream factors (such as Mx, PKR, OAS, and IL-8) in duck embryo fibroblast cells. What is more, RNA interference further confirmed that duMAVS was an important adaptor for IFN-ß activation. The antiviral assay showed that duMAVS could suppress the various viral replications (DTMUV, novel reovirus, and duck plague virus) at early stages of infection. Overall, these results showed that the main signal pathway mediated by duMAVS and it had a broad-spectrum antiviral ability. This research will be helpful to better understanding the innate immune system of ducks.

7.
Asian-Australas J Anim Sci ; 29(7): 1037-43, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26954143

RESUMO

Epigenetic processes in the development of skeletal muscle have been appreciated for over a decade. DNA methylation is a major epigenetic modification important for regulating gene expression and suppressing spurious transcription. Up to now, the importance of epigenetic marks in the regulation of Pax7 and myogenic regulatory factors (MRFs) expression is far less explored. In the present study, semi-quantitative the real-time polymerase chain reaction (RT-PCR) analyses showed MyoD and Myf5 were expressed in activated and quiescent C2C12 cells. MyoG was expressed in a later stage of myogenesis. Pax7 was weakly expressed in differentiated C2C12 cells. To further understand the regulation of expression of these genes, the DNA methylation status of Pax7, MyoD, and Myf5 was determined by bisulfite sequencing PCR. During the C2C12 myoblasts fusion process, the changes of promoter and exon 1 methylation of Pax7, MyoD, and Myf5 genes were observed. In addition, an inverse relationship of low methylation and high expression was found. These results suggest that DNA methylation may be an important mechanism regulating Pax7 and MRFs transcription in cell myogenic differentiation.

8.
Microb Pathog ; 65: 67-72, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24113000

RESUMO

We analyzed the complete genomic sequences of 17 porcine reproductive and respiratory syndrome virus (PRRSV) isolates from Southern China obtained between 2010 and 2011 and found that four of seven isolates from 2011 were closely related to the JXA1-R strain (vaccine virus of JXA1). This close relationship between field isolates and China domestic vaccine viruses has not been reported to date. The occurrence of vaccine-like viruses potentially creates a threat for the pig breeding industry and brings difficulties for control of this disease.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vacinas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , China/epidemiologia , Variação Genética , Genoma Viral , Genótipo , Dados de Sequência Molecular , Filogenia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Alinhamento de Sequência , Análise de Sequência de DNA , Suínos
9.
Acta Vet Hung ; 60(1): 157-64, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22366140

RESUMO

To understand the genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) in South China, we collected 231 clinical samples from pigs with suspected PRRSV infection in Guangdong between 2007 and 2009. We found that 74 of 231 samples were positive by RT-PCR. The PCR products of the ORF5 gene of 35 isolates from different farms were sequenced and their DNA sequences were compared to 23 other PRRSV isolates in the GenBank. We found that the nucleotide similarity among all South China isolates ranged from 87.6% to 100%, and all belonged to the North American genotype. Most of them were classified into subgenotype I, but the rest mapped to subgenotypes III, V or VI. Those in subgenotypes I and III were found to be highly variable in the primary neutralising epitope (PNE) with a specific amino acid mutation (F39/L39→I39), and a few isolates in subgenotypes I and III isolates also had a mutation at L41 (L41→S41). PRRSV isolates in subgenotypes III, V and VI had less potential glycosylation sites than those in subgenotype I. Our data contribute to the understanding of molecular variation of PRRSV in South China.


Assuntos
Variação Genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , China/epidemiologia , Regulação Viral da Expressão Gênica , Dados de Sequência Molecular , Filogenia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Suínos , Proteínas do Envelope Viral
10.
Infect Genet Evol ; 11(5): 1174-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21382518

RESUMO

This is the first report of avian-like H6N6 swine influenza virus from swine in southern China. Phylogenetic analysis indicated that this virus might originate from domestic ducks. Serological surveillance suggested there had been sporadic H6 swine influenza infections in this area. Continuing study is required to determine if this virus could be established in the swine population and pose potential threats to public health.


Assuntos
Vírus da Influenza A/genética , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , China/epidemiologia , Vírus da Influenza A/classificação , Dados de Sequência Molecular , Infecções por Orthomyxoviridae/virologia , Filogenia , Suínos , Doenças dos Suínos/epidemiologia
11.
Virol J ; 8: 144, 2011 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-21447173

RESUMO

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) has been acknowledged as one of the most important agents affecting swine. The scavenger receptor CD163 is one of the important entry mediators for PRRSV. RESULTS: The tD4 and tD5 CD163 genes were amplified, and the PCR products were cloned into pET-28a(+) (designated pET-28a-tD4 and pET-28a-tD5, respectively). The plasmids pET-28a-tD4 and pET-28a-tD5 were then transformed into the E. coli BL21 (DE3) strain and expressed by adding 1 mmol/L of isopropyl-beta-D-thiogalactopyranoside. The proteins were highly expressed in the supernatant from the tD4- and tD5-producing cells that were incubated with a binding buffer containing the following compounds: ß-mercaptoethanol, urea, Tween 20, glycerol, and SDS, while they were rarely expressed in the supernatant from the tD4- and tD5-producing cells that were incubated with binding buffer without the compounds. The tD4 and tD5 proteins were purified, and BALB/c mice were immunized with the purified proteins. Western blotting analysis showed that the tD4 and tD5 proteins were capable of reacting with tD5 antibodies; the titer of both the tD4 and tD5 antiserums was 1:160 against the tD5 protein, as shown by ELISA. CONCLUSIONS: These studies provide a new way for the purification of proteins expressed in inclusion bodies and the preparation of the corresponding antibodies.


Assuntos
Anticorpos/isolamento & purificação , Antígenos CD/química , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/química , Antígenos de Diferenciação Mielomonocítica/imunologia , Receptores de Superfície Celular/química , Receptores de Superfície Celular/imunologia , Suínos/imunologia , Animais , Anticorpos/imunologia , Antígenos CD/genética , Antígenos de Diferenciação Mielomonocítica/genética , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Terciária de Proteína , Receptores de Superfície Celular/genética , Suínos/genética
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