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1.
Virus Genes ; 59(2): 240-243, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36735176

RESUMO

In 2021, an H7N3 avian influenza virus (AIV) was isolated from a mallard in Tianhewan Yellow River National Wetland Park, Ningxia Hui Autonomous Region, China. Sequences analysis showed that this strain received its genes from H7, H6, H5, H3, and H1 AIVs of domestic poultry and wild birds in Asia and Europe. It was mild pathogenicity in mice. These results suggest the importance of continued surveillance of the H7N3 virus to better understand the ecology and evolution of the AIVs in poultry and wild birds and the potential threat to humans.


Assuntos
Influenza Aviária , Humanos , Animais , Camundongos , Vírus da Influenza A Subtipo H7N3/genética , Filogenia , Animais Selvagens/genética , Aves , Aves Domésticas , Análise de Sequência
2.
Virus Genes ; 59(3): 410-416, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36781819

RESUMO

Avian influenza virus (AIV) infection can lead to severe economic losses in the poultry industry and causes a serious risk for humans. A rapid and simple test for suspected viral infection cases is crucial. In this study, a reverse transcription recombinase-aided amplification assay (RT-RAA) for the rapid detection of all AIV subtypes was developed. The reaction temperature of the assays is at 39 °C and the detection process can be completed in less than 20 min. The specificity results of the assay showed that this method had no cross-reaction with other main respiratory viruses that affect birds, including Newcastle disease virus (NDV) and infectious bronchitis virus (IBV). The analytical sensitivity at a 95% confidence interval was 102 RNA copies per reaction. In comparison with a published assay for reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), the κ value of the RT-RAA assay in 384 avian clinical samples was 0.942 (p < 0.001). The sensitivity and specificity of the RT-RAA assay for avian clinical sample detection was determined as 97.59% (95% CI 93.55-99.23%) and 96.79% (95% CI 93.22-98.59%), respectively. The RT-RAA assay for AIV in this study provided an effective and practicable tool for AIV molecular detection.


Assuntos
Vírus da Influenza A , Influenza Aviária , Animais , Humanos , Transcrição Reversa , Influenza Aviária/diagnóstico , Recombinases/genética , Recombinases/metabolismo , Vírus da Influenza A/genética , Aves/genética , Sensibilidade e Especificidade
3.
Virus Genes ; 59(4): 554-561, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37184730

RESUMO

In October 2020, an avian paramyxovirus serotype 14 (APMV-14)-designated chicken/Fujian/2160/2020 (FJ2160) was isolated from tracheal and cloacal swab sample of chicken collected from live bird market in Fujian province in China during the active surveillance program. The complete genome of FJ2160 comprised 15,444 nucleotides (nt) complying with the paramyxovirus "rule of six" and encoded six non-overlapping structural proteins in the order of 3'-NP-P-M-F-HN-L-'5. The complete genome sequence analysis showed that FJ2160 had the highest identity (90.0%) with the APMV-14 isolated from Japan, while the nucleotide sequence identities of FJ2160 and other APMVs ranged from 42.4 to 51.1%. The F protein cleavage site was TREGR↓L, which resembled a lentogenic strain of APMV-1. Phylogenetic analysis revealed that the FJ2160 closest relative was APMV-14. The intracerebral pathogenicity index (ICPI) tests indicated that the virus was lentogenic. This is the first report of APMV-14 in China. These results provide evidence that APMV-14 could infect chickens and reveal the genetic characteristics and biological properties of the virus, which can help to better understand this new emerging APMV-14.


Assuntos
Avulavirus , Galinhas , Animais , Sorogrupo , Genoma Viral/genética , Avulavirus/genética , Filogenia , China
4.
BMC Vet Res ; 19(1): 5, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624468

RESUMO

BACKGROUND: Fowl adenovirus is of major concern to the poultry industry worldwidely. In order to monitor the prevalent status of Fowl adenovirus in China, a total of 1920 clinical samples from apparently healthy birds in the 25 sites of poultry flocks, Slaughterhouse and living bird markets from 8 provinces in eastern China were collected and detected by PCR, sequencing, and phylogenetic analysis. RESULTS: The epidemiological survey showed that Fowl adenoviruses were detected in living bird markets, and circulating in a variety of fowl species, including chickens, ducks, goose and pigeons. Among the 1920 clinical samples, 166 samples (8.65%) were positive in the fowl adenovirus PCR detection. In this study, totally all the 12 serotypes (serotypes of 1, 2, 3, 4, 5, 6, 7, 8A, 8B, 9, 10 and 11) fowl adenoviruses were detected, the most prevalent serotype was serotype 1. Phylogenetic analysis indicated that 166 FAdVs of 12 serotypes were divided into 5 fowl adenovirus species (Fowl aviadenovirus A, B, C, D, E). CONCLUSIONS: In the epidemiological survey, 8.65% of the clinical samples from apparently healthy birds were positive in the fowl adenovirus PCR detection. Totally all the 12 serotypes fowl adenoviruses were detected in a variety of fowl species, which provided abundant resources for the research of fowl adenoviruses in China. The newly prevalent FAdV serotypes provides valuable information for the development of an effective control strategy for FAdV infections in fowls.


Assuntos
Infecções por Adenoviridae , Aviadenovirus , Doenças das Aves Domésticas , Animais , Doenças das Aves Domésticas/epidemiologia , Infecções por Adenoviridae/epidemiologia , Infecções por Adenoviridae/veterinária , Epidemiologia Molecular , Filogenia , Galinhas , Aviadenovirus/genética , China/epidemiologia , Sorogrupo
5.
Emerg Infect Dis ; 28(5): 1064-1066, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35447059

RESUMO

A novel highly pathogenic avian influenza A(H5N6) clade 2.3.4.4b virus was isolated from a poultry market in China that a person with a confirmed case had visited. Most genes of the avian and human H5N6 isolates were closely related. The virus also exhibited distinct antigenicity to the Re-11 vaccine strain.


Assuntos
Vírus da Influenza A , Influenza Aviária , Influenza Humana , Animais , Aves , China/epidemiologia , Humanos , Vírus da Influenza A/genética , Influenza Aviária/epidemiologia , Influenza Humana/epidemiologia , Filogenia , Aves Domésticas , Vírus Reordenados/genética
6.
Virol J ; 19(1): 129, 2022 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-35907986

RESUMO

BACKGROUND: The H5 subtype avian influenza virus (AIV) has caused huge economic losses to the poultry industry and is a threat to human health. A rapid and simple test is needed to confirm infection in suspected cases during disease outbreaks. METHODS: In this study, we developed a reverse transcription recombinase-aided amplification (RT-RAA) assay for the detection of H5 subtype AIV. Assays were performed at a single temperature (39 °C), and the results were obtained within 20 min. RESULTS: The assay showed no cross-detection with Newcastle disease virus or infectious bronchitis virus. The analytical sensitivity was 103 RNA copies/µL at a 95% confidence interval according to probit regression analysis, with 100% specificity. Compared with published reverse transcription quantitative real-time polymerase chain reaction assays, the κ value of the RT-RAA assay in 420 avian clinical samples was 0.983 (p < 0.001). The sensitivity for avian clinical sample detection was 97.26% (95% CI, 89.56-99.52%), and the specificity was 100% (95% CI, 98.64-100%). CONCLUSIONS: These results indicated that our RT-RAA assay may be a valuable tool for detecting H5 subtype AIV.


Assuntos
Vírus da Influenza A , Influenza Aviária , Animais , Aves , Humanos , Vírus da Influenza A/genética , Vírus da Influenza A/metabolismo , Influenza Aviária/diagnóstico , Recombinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Reversa , Sensibilidade e Especificidade
7.
Emerg Infect Dis ; 26(2)2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-31855533

RESUMO

In China, influenza A(H7N9) virus appeared in 2013, then mutated into a highly pathogenic virus, causing outbreaks among poultry and cases in humans. Since September 2017, extensive use of the corresponding vaccine, H7-Re1, successfully reduced virus prevalence. However, in 2019, a novel antigenic variant emerged, posing considerable economic and public health threats.A.

8.
Virol J ; 16(1): 85, 2019 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-31242907

RESUMO

BACKGROUND: Type A influenza viruses (IAVs) cause significant infections in humans and multiple species of animals including pigs, horses, birds, dogs and some marine animals. They are of complicated phylogenetic diversity and distribution, and analysis of their phylogenetic diversity and distribution from a panorama view has not been updated for multiple years. METHODS: 139,872 protein sequences of IAVs from GenBank were selected, and they were aligned and phylogenetically analyzed using the software tool MEGA 7.0. Lineages and subordinate lineages were classified according to the topology of the phylogenetic trees and the host, temporal and spatial distribution of the viruses, and designated using a novel universal nomenclature system. RESULTS: Large phylogenetic trees of the two external viral genes (HA and NA) and six internal genes (PB2, PB1, PA, NP, MP and NS) were constructed, and the diversity and the host, temporal and spatial distribution of these genes were calculated and statistically analyzed. Various features regarding the diversity and distribution of IAVs were confirmed, revised or added through this study, as compared with previous reports. Lineages and subordinate lineages were classified and designated for each of the genes based on the updated panorama views. CONCLUSIONS: The panorama views of phylogenetic diversity and distribution of IAVs and their nomenclature system were updated and assumed to be of significance for studies and communication of IAVs.


Assuntos
Evolução Molecular , Variação Genética , Vírus da Influenza A/genética , Filogenia , Sequência de Aminoácidos , Animais , Aves/virologia , Quirópteros/virologia , Cães/virologia , Genes Virais , Cavalos/virologia , Humanos , Suínos/virologia
9.
Virus Genes ; 55(3): 411-414, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30895439

RESUMO

In 2017, an H7N8 avian influenza virus (AIV) was isolated from a domestic duck from a farm in Central China. Sequences analysis showed that this strain received its genes from H7, H1, H2, H3, H5, and H6 AIVs of domestic poultry and wild birds in Asia. It exhibited low pathogenicity in chickens and mild pathogenicity in mice. These results suggest the importance of continued surveillance of the H7N8 virus to better understand the ecology and evolution of the AIVs in poultry and wild birds and the potential threat to human health.


Assuntos
Patos/virologia , Vírus da Influenza A/genética , Influenza Aviária/virologia , Influenza Humana/virologia , Doenças das Aves Domésticas/virologia , Animais , Animais Domésticos/virologia , Animais Selvagens , Galinhas/virologia , China , Humanos , Vírus da Influenza A/patogenicidade , Influenza Aviária/transmissão , Influenza Humana/transmissão , Camundongos , Filogenia , Aves Domésticas/virologia , Doenças das Aves Domésticas/transmissão
10.
J Oral Maxillofac Surg ; 77(11): 2221.e1-2221.e14, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31356802

RESUMO

PURPOSE: A surgical procedure to minimize the incidence of inferior alveolar nerve injury (IANI) in deeply impacted mandibular third molars (IMTMs) has been proposed. Our study compared the near-term outcomes between coronectomy and traditional extraction of IMTMs and evaluated the long-term complications after coronectomy using cone-beam computed tomography (CBCT). PATIENTS AND METHODS: A prospective study was performed of patients with IMTMs at high-risk of IANI using radiographic examination and CBCT. The patients were divided into 2 groups: a coronectomy group and an extraction group. The short-term outcomes, including IANI and other conditions, such as bleeding, pain, and swelling, were assessed in both groups 1 week after surgery. The coronectomy patients were evaluated at 3, 6, 12, and 36 months after the procedure. The primary long-term complications assessed included root migration, secondary included inflammation, socket healing, and eruption. Relevant factors affecting the outcomes (ie, age, gender, root morphology, impacted depth, impacted angle) were also analyzed. The data were analyzed using SPSS Statistics, version 20.0 (IBM Corp, Armonk, NY). RESULTS: A total of 110 IMTMs (55 in the coronectomy group and 55 in the extraction group) in 92 patients (49 men and 43 women) were included in CBCT assessment. IANI was found in 6 patients in the extraction group and no patient in the coronectomy group (P < .05). After 6 months, 2 patients still presented with light numbness. After coronectomy, the roots had migrated quickly during the initial 6 months and had become stable 1 year after surgery; 90.9% of the roots had migrated away from the mandibular nerve canal at 6 months postoperatively. No infection had occurred within the 3-year follow-up period. CONCLUSIONS: Coronectomy should be considered superior to traditional extraction in the management of the risk of IANI, with few additional complications occurring during follow-up. It could be used as a useful and safe clinical treatment of IMTMs with a high risk of IANI.


Assuntos
Extração Dentária , Dente Impactado , Traumatismos do Nervo Trigêmeo , Feminino , Humanos , Masculino , Mandíbula , Nervo Mandibular , Dente Serotino , Estudos Prospectivos , Coroa do Dente , Dente Impactado/cirurgia
11.
Biochem Cell Biol ; 96(1): 11-18, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29024600

RESUMO

Diabetic cardiomyopathy (DCM) is defined as ventricular dysfunction occurring independently of a recognized cause such as hypertension or coronary artery disease. Liver X receptor α (LXRα), a subtype of ligand-activated transcription factors LXRs, has been considered as a potential pharmacological target in the pathogenesis of cardiovascular and metabolic diseases. However, the potential mechanism of how LXRα is regulated in cardiomyocytes is still unclear. This study investigated the effect of activating LXRα with GW3965 on cardiomyocyte apoptosis and its upstream regulator in glucose-induced H9C2 cells. Our data indicated that GW3965 up-regulated the expression of LXRα, inhibited cardiomyocyte apoptosis, and altered the apoptosis-related proteins in glucose-induced H9C2 cells. In addition, GW3965 restored the mitochondrial membrane potential level and decreased the ROS production induced by glucose. Moreover, LXRα was confirmed as a direct target of microRNA-1 (miR-1) that was involved in cardiomyocyte apoptosis of DCM, and overexpression of miR-1 abrogated the inhibiting effect of GW3965 on glucose-induced apoptosis in H9C2 cells. This study highlights an important role of LXRα in the development of DCM and brings new insights into the complex mechanisms involved in the pathogenesis of DCM.


Assuntos
Apoptose/efeitos dos fármacos , Receptores X do Fígado/antagonistas & inibidores , MicroRNAs/farmacologia , Mitocôndrias/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Receptores X do Fígado/metabolismo , MicroRNAs/genética , Mitocôndrias/metabolismo , Ratos
12.
J Gen Virol ; 99(12): 1600-1607, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30358528

RESUMO

The H5 subtype of highly pathogenic avian influenza (HPAI) viruses pose a serious challenge to public health and the poultry industry in China. In this study, we generated a chimeric QH/KJ recombinant virus expressing the entire haemagglutinin (HA)-1 region of the HPAI virus A/chicken/China/QH/2017(H5N6) (clade 2.3.4.4) and the HA2 region of the HPAI virus A/chicken/China/KJ/2017(H5N1) (clade 2.3.2.1). The resulting chimeric PR8-QH/KJ virus exhibited similar in vitro growth kinetics as the parental PR8-QH and PR8-KJ viruses. The chimeric PR8-QH/KJ virus induced specific, cross-reactive haemagglutination-inhibition and serum-neutralizing antibodies against both QH and KJ viruses, although PR8-QH and PR8-KJ exhibited no cross-reactivity with each other. Furthermore, the chimeric PR8-QH/KJ vaccine significantly reduced virus shedding and completely protected chickens from challenge with HPAI H5N6 and H5N1 viruses. However, the Re-8 vaccine against clade 2.3.4.4 viruses provided specific-pathogen-free chickens only partial protection when challenged with QH virus. Our results suggest that the antigenic variation of these epidemic viruses occurred and they can escape the current vaccine immunization. The Re-8 vaccine needs an update. The chimeric PR8-QH/KJ vaccine is effective against H5 HPAI virus clades 2.3.4.4 and 2.3.2.1 in chickens.


Assuntos
Anticorpos Antivirais/sangue , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vacinas contra Influenza/imunologia , Influenza Aviária/prevenção & controle , Animais , Anticorpos Neutralizantes/sangue , Galinhas , China , Reações Cruzadas , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Vacinas contra Influenza/administração & dosagem , Influenza Aviária/virologia , Testes de Neutralização , Análise de Sobrevida , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia
13.
Microb Pathog ; 123: 398-401, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30063975

RESUMO

Toxoplasma gondii is an intracellular protozoan parasite infecting human and almost all warm-blooded animals. It may cause several severe symptoms if pregnant women infection with T. gondii, including misbirth. A cross-sectional study was conducted containing 313 Manchu pregnant women attending antenatal care from 2016 to 2017 in Jilin province, northeastern China, and were assessed by enzyme-link immunosorbent assay and the study utilized univariate analysis to identify the potential risk factors for T. gondii infection. Of the 313 investigated Manchu pregnant women, 51 (16.29%, 95% CI 12.2-20.4) were tested as T. gondii-seropositive, with 47 (15.02%) seropositive for T. gondii IgG antibodies and 8 (2.56%) IgM positive. The seroprevalence of T. gondii in different age groups varied from 13.50% (8.7-18.3) to 23.90% (13.9-41.9). Pregnant raising cat at home has a significantly higher seroprevalence of T. gondii than no cat at home. Pregnant consuming raw/undercooked meat has a significantly higher T. gondii seroprevalence than individuals did not consuming raw/undercooked meat. This is the first study of T. gondii infection seroprevalence in Manchu pregnant women. Risk factors analysis suggested that seroprevalence of T. gondii in investigated Manchu pregnant women was mainly related to consumption of raw/undercooked meat and raising cat at home. The findings will provide key and baseline data for prevention and control of toxoplasmosis among Manchu pregnant women and other people.


Assuntos
Anticorpos Antiprotozoários/sangue , Toxoplasma/imunologia , Toxoplasmose/sangue , Toxoplasmose/epidemiologia , Adulto , Fatores Etários , Animais , Gatos , China/epidemiologia , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Etnicidade , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Carne/parasitologia , Gravidez , Fatores de Risco , Estudos Soroepidemiológicos , Toxoplasmose/imunologia , Adulto Jovem
14.
Wei Sheng Wu Xue Bao ; 55(12): 1619-25, 2015 Dec 04.
Artigo em Zh | MEDLINE | ID: mdl-27101705

RESUMO

OBJECTIVE: We explored which internal genes of influenza virus that affect the titer of recombinant viruses and contribute to the high yield of Influenza A seed virus in ovo. METHODS: Six internal genes or mutant or polymerase complex of A/Puerto Rico/8/1934 (H1N1) (PR8) virus genes were replaced individually by corresponding gene of A/ chicken/ZJ/China/2013 ( H5N1) virus, and the hemagglutination titers of recombinant viruses were compared by HA assay. RESULTS: PB2 gene had the greatest influence, its replace failed to generate recombinant virus. When PB1, PA, or M gene was replaced, the titers of recombinant viruses dropped by 3.7, 3.4, 3.0 (log2), respectively. NS gene had little influence upon HA titer. When polymerase complex genes were replaced, virus titer dropped slightly to 7.6 log2, and it did not confer the same growth characteristics (8.4 log2) found when a complete polymerase complex was of PR8 origin. When amino acids of position 627 of PR8 PB2 gene were mutated to glutamic acid, virus titer rose from 8.4 log2 to 8.7 log2. CONCLUSION: The optimal gene combinations may facilitate replication through viral RNA and protein interaction with cellular components as well as interaction of viral RNA and protein or protein-protein interactions within the virus. These multi-factorial contributions resulted in selection of a high replication competent reassortant in embryonated chicken eggs in comparison to the respective low yield wild type viruses, and laid the foundation for high


Assuntos
Vírus da Influenza A Subtipo H1N1/crescimento & desenvolvimento , Virus da Influenza A Subtipo H5N1/crescimento & desenvolvimento , Proteínas Virais/metabolismo , Animais , Embrião de Galinha , Galinhas , Humanos , Vírus da Influenza A Subtipo H1N1/genética , Vírus da Influenza A Subtipo H1N1/metabolismo , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/metabolismo , Influenza Humana/virologia , Proteínas Virais/genética
15.
Emerg Infect Dis ; 20(12): 2152-4, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25418710

RESUMO

Subclinical infection of vaccinated chickens with a highly pathogenic avian influenza A(H5N2) virus was identified through routine surveillance in China. Investigation suggested that the virus has evolved into multiple genotypes. To better control transmission of the virus, we recommend a strengthened program of education, biosecurity, rapid diagnostics, surveillance, and elimination of infected poultry.


Assuntos
Infecções Assintomáticas , Galinhas/virologia , Vírus da Influenza A/classificação , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Animais , China/epidemiologia , Genótipo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A/genética , Vírus da Influenza A/imunologia , Filogenia , Vacinação
16.
Virus Genes ; 49(3): 493-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25142163

RESUMO

Bovine influenza virus was first identified in the USA in 2013, and the virus represents a potential novel type of influenza viruses. However, the distribution and evolution of the virus remain unknown. We conducted a pilot survey of bovine influenza virus in China, and identified three bovine influenza viruses which are highly homogenous to the ones identified in the USA, suggesting that the bovine influenza virus likely circulates widely and evolves slowly in the world.


Assuntos
Doenças dos Bovinos/virologia , Infecções por Orthomyxoviridae/veterinária , Orthomyxoviridae/classificação , Orthomyxoviridae/isolamento & purificação , Animais , Bovinos , China , Análise por Conglomerados , Dados de Sequência Molecular , Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Filogenia , Análise de Sequência de DNA , Homologia de Sequência
17.
Vet Microbiol ; 292: 110038, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38458047

RESUMO

In 2020, an H5N1 avian influenza virus of clade 2.3.4.4b was detected in Europe for the first time and was spread throughout the world by wild migratory birds, resulting in the culling of an unprecedented number of wild birds and poultry due to the epidemic. In February 2023, we isolated and identified a strain of H5N1 high pathogenicity avian influenza virus from a swab sample from a grey crane in Ningxia, China. Phylogenetic analysis of the Hemagglutinin (HA) gene showed that the virus belonged to clade 2.3.4.4b, and several gene segments were closely related to H5N1 viruses infecting humans in China. Analysis of key amino acid sites revealed that the virus contained multiple amino acid substitutions that facilitate enhanced viral replication and mammalian pathogenicity. The results of animal challenge experiments showed that the virus is highly pathogenic to chickens, moderately pathogenic to BALB/c mice, and highly infectious but not lethal to mallards. Moreover, the virus exhibited minor antigenic drift compared with the H5-Re14 vaccine strain. To this end, we need to pay more attention to the monitoring of wild birds to prevent further spread of viruses to poultry and mammals, including humans.


Assuntos
Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Doenças dos Roedores , Humanos , Camundongos , Animais , Aves Domésticas , Galinhas , Filogenia , Virulência , Patos , Animais Selvagens , Mamíferos
18.
Chin Sci Bull ; 58(26): 3183-3187, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-32214742

RESUMO

Dozens of human cases infected with H7N9 subtype avian influenza virus (AIV) have been confirmed in China since March, 2013. Distribution data of sexes, ages, professions and regions of the cases were analyzed in this report. The results showed that the elderly cases, especially the male elderly, were significantly more than expected, which is different from human cases of H5N1 avian influenza and human cases of the pandemic H1N1 influenza. The outbreak was rated as a Grade III (severe) outbreak, and it would evolve into a Grade IV (very severe) outbreak soon, using a method reported previously. The H7N9 AIV will probably circulate in humans, birds and pigs for years. Moreover, with the driving force of natural selection, the virus will probably evolve into highly pathogenic AIV in birds, and into a deadly pandemic influenza virus in humans. Therefore, the H7N9 outbreak has been assumed severe, and it is likely to become very or extremely severe in the future, highlighting the emergent need of forceful scientific measures to eliminate any infected animal flocks. We also described two possible mild scenarios of the future evolution of the outbreak.

19.
Front Plant Sci ; 14: 1260808, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37929164

RESUMO

The typical occlusion of cherry tomatoes in the natural environment is one of the most critical factors affecting the accurate picking of cherry tomato picking robots. To recognize occluded cherry tomatoes accurately and efficiently using deep convolutional neural networks, a new occluded cherry tomato recognition model DSP-YOLOv7-CA is proposed. Firstly, images of cherry tomatoes with different degrees of occlusion are acquired, four occlusion areas and four occlusion methods are defined, and a cherry tomato dataset (TOSL) is constructed. Then, based on YOLOv7, the convolution module of the original residual edges was replaced with null residual edges, depth-separable convolutional layers were added, and jump connections were added to reuse feature information. Then, a depth-separable convolutional layer is added to the SPPF module with fewer parameters to replace the original SPPCSPC module to solve the problem of loss of small target information by different pooled residual layers. Finally, a coordinate attention mechanism (CA) layer is introduced at the critical position of the enhanced feature extraction network to strengthen the attention to the occluded cherry tomato. The experimental results show that the DSP-YOLOv7-CA model outperforms other target detection models, with an average detection accuracy (mAP) of 98.86%, and the number of model parameters is reduced from 37.62MB to 33.71MB, which is better on the actual detection of cherry tomatoes with less than 95% occlusion. Relatively average results were obtained on detecting cherry tomatoes with a shade level higher than 95%, but such cherry tomatoes were not targeted for picking. The DSP-YOLOv7-CA model can accurately recognize the occluded cherry tomatoes in the natural environment, providing an effective solution for accurately picking cherry tomato picking robots.

20.
Front Microbiol ; 14: 1286713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029110

RESUMO

Avian influenza viruses (AIV) pose a significant persistent threat to the public health and safety. It is estimated that there have been over 100 outbreaks caused by various H7 subtypes of avian influenza viruses (AIV-H7) worldwide, resulting in over 33 million deaths of poultry. In this study, we developed a recombinase-aided amplification combined with a lateral flow dipstick assay for the detection of hemagglutinin (HA) genes to provide technical support for rapid clinical detection of AIV-H7. The results showed that the assay can complete the reaction within 30 min at a temperature of 39°C. Specificity tests demonstrated that there was no cross-reactivity with other common poultry pathogens, including Newcastle disease virus (NDV) and infections bronchitis virus (IBV). The detection limit of this assay was 1 × 101 copies/µL, while RT-qPCR method was 1 × 101 copies/µL, and RT-PCR was 1 × 102 copies/µL. The κ value of the RT-RAA-LFD and RT-PCR assay in 132 avian clinical samples was 0.9169 (p < 0.001). These results indicated that the developed RT-RAA-LFD assay had good specificity, sensitivity, stability and repeatability and may be used for rapid detection of AIV-H7 in clinical diagnosis.

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