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1.
J Anim Physiol Anim Nutr (Berl) ; 108(4): 1072-1082, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38528677

RESUMO

This study aimed to investigate the effects of fermented tofu processing wastewater (FTPW) on the growth performance and meat quality of Xianghuang broilers. A total of 160 six-week-old Xianghuang broilers were randomly assigned to control or FTPW groups with eight replicate pens of 10 birds each pen. Broilers received the same corn-soybean diet but different water. Broilers received ordinary water in the control group and 40% (volume: volume) FTPW (the solution has been filtered with four layers of sieve, containing Bacillus 1.52 × 10-7 CFU/mL) in FTPW group. The experiment lasted for 30 days. Results indicated that growth performance was not affected by treatment (p > 0.05). The value of pH45 min and a48 h increased and drip loss72 h and toughness decreased in breast muscle when broilers received FTPW solution compared with the control group (p < 0.05). The pH45 min, a45 min, a48 h value and crude fat concentration of thigh muscle were higher in FTPW group than that in control group (p < 0.05). Compared with control group, fibre area decreased but fibre density increased in thigh muscle when Xianghuang chickens supplemented with FTPW solution (p < 0.05). Supplementation of FTPW solution in drinking water significantly decreased malondialdehyde content in the breast muscle of Xianghuang chickens (p < 0.05). Gene expressions such as carnitine palmitoyltransferase 1A (CPT1) and glycogen synthase of breast muscle were downregulated in experimental group when compared with control group. In conclusion, FTPW supplementation in drinking water could improve meat quality of Xianghuang broilers by regulating pH value, redness and fibre morphology.


Assuntos
Ração Animal , Galinhas , Dieta , Fermentação , Carne , Águas Residuárias , Animais , Carne/normas , Ração Animal/análise , Dieta/veterinária , Águas Residuárias/química , Alimentos de Soja , Fenômenos Fisiológicos da Nutrição Animal , Manipulação de Alimentos
2.
J Cancer Res Clin Oncol ; 149(20): 17855-17863, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37947870

RESUMO

PURPOSE: Ultrasound imaging is the preferred method for the early diagnosis of endometrial diseases because of its non-invasive nature, low cost, and real-time imaging features. However, the accurate evaluation of ultrasound images relies heavily on the experience of radiologist. Therefore, a stable and objective computer-aided diagnostic model is crucial to assist radiologists in diagnosing endometrial lesions. METHODS: Transvaginal ultrasound images were collected from multiple hospitals in Quzhou city, Zhejiang province. The dataset comprised 1875 images from 734 patients, including cases of endometrial polyps, hyperplasia, and cancer. Here, we proposed a based self-supervised endometrial disease classification model (BSEM) that learns a joint unified task (raw and self-supervised tasks) and applies self-distillation techniques and ensemble strategies to aid doctors in diagnosing endometrial diseases. RESULTS: The performance of BSEM was evaluated using fivefold cross-validation. The experimental results indicated that the BSEM model achieved satisfactory performance across indicators, with scores of 75.1%, 87.3%, 76.5%, 73.4%, and 74.1% for accuracy, area under the curve, precision, recall, and F1 score, respectively. Furthermore, compared to the baseline models ResNet, DenseNet, VGGNet, ConvNeXt, VIT, and CMT, the BSEM model enhanced accuracy, area under the curve, precision, recall, and F1 score in 3.3-7.9%, 3.2-7.3%, 3.9-8.5%, 3.1-8.5%, and 3.3-9.0%, respectively. CONCLUSION: The BSEM model is an auxiliary diagnostic tool for the early detection of endometrial diseases revealed by ultrasound and helps radiologists to be accurate and efficient while screening for precancerous endometrial lesions.


Assuntos
Médicos , Lesões Pré-Cancerosas , Doenças Uterinas , Humanos , Feminino , Simulação por Computador , Hospitais , Hiperplasia , Lesões Pré-Cancerosas/diagnóstico por imagem
3.
Environ Sci Pollut Res Int ; 30(53): 113718-113728, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37853218

RESUMO

Currently, the effects of earthworm inoculation on cadmium-contaminated rice field remain unclear. In this study, four treatments were tested, including rice monoculture (CK), earthworm inoculation with low density (L, 30 g/m2), middle density (M, 60 g/m2), and high density (H, 90 g/m2). The pot and field experiment were conducted in Hunan Province, China. In the pot experiment, the H treatment significantly decreased the available cadmium concentration in 0 ~ 20 cm soil by 5.21% ~ 16.51%, and the M treatment significantly decreased in 0 ~ 10 cm soil by 7.29% ~ 8.96%. The H treatment significantly decreased the total cadmium concentration in 0 ~ 5 cm soil by 10.36%. Moreover, the earthworm inoculation treatments significantly reduced cadmium accumulation in rice organs. In the field experiment, the M and H treatment decreased the available cadmium concentration in 0 ~ 20 cm soil by 14.05% ~ 47.52% and the H treatment decreased the total cadmium concentration in 0 ~ 20 cm soil by 0.78% ~ 5.75% although there was no significant difference. Furthermore, the earthworm inoculation treatments significantly decreased cadmium accumulation in part of rice organs. In conclusion, this study recommends that earthworm inoculation is an effective method of controlling cadmium contamination for rice production.


Assuntos
Oligoquetos , Oryza , Poluentes do Solo , Animais , Cádmio/análise , Poluentes do Solo/análise , Solo , China
4.
ACS Omega ; 8(30): 27710-27724, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37546590

RESUMO

As a key bridge between logging and seismic data, acoustic (AC) logging data is of great significance for reservoir lithology, physical property analysis, and quantitative evaluation, and completing AC logging data can help to obtain high-resolution inversion profiles, which can provide a reliable basis for reservoir geological interpretation. However, in the actual mining process, the AC logging data is always missing due to instrument failure and borehole collapse in many areas, and re-logging is not only expensive but also difficult to achieve. However, the AC data can be completed by other obtained logging parameters. In this paper, a bidirectional gated recurrent unit network based on the Inception module is developed to complete the AC logging data. The Inception module extracts the logging data features and inputs the extracted logging data features into the bidirectional gated recurrent unit network, which can fully consider the characteristics of the current data and the data before and after the logging sequence to complete the missing AC logging data. Experimental results show that the hybrid model (Inception-BiGRU) has higher accuracy than traditional and widely used series forecasting models (gated recurrent unit network and long short-term memory network), and this method also provides a new idea for the completion of AC logging data.

5.
ACS Omega ; 8(26): 24083-24092, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37426272

RESUMO

Porosity is an integral part of reservoir evaluation, but in the field of reservoir prediction, due to the complex nonlinear relationship between logging parameters and porosity, linear models cannot accurately predict porosity. Therefore, this paper uses machine learning methods that can better handle the relationship between nonlinear logging parameters and porosity to predict porosity. In this paper, logging data from Tarim Oilfield are selected for model testing, and there is a nonlinear relationship between these parameters and porosity. First, the data features of the logging parameters are extracted by the residual network, which uses the "hop connections" method to transform the original data closer to the target variable. In addition, the residual blocks inside the residual network use jump connections, which alleviates the gradient vanishing problem caused by increasing depth in deep neural networks. The dynamic nature of data would necessitate LSTM in the first place. Then, a bidirectional long short-term network (BiLSTM) is used to predict the porosity of the extracted logging data features. Among them, the BiLSTM is composed of two independent reverse LSTMs, which can better solve the nonlinear prediction problem. In order to further improve the accuracy of the model, this paper introduces an attention mechanism to learn by weighting each of the inputs in proportion to their impact on the porosity. The experimental results also show that the data features extracted by the residual neural network can be better used as the input of the BiLSTM model.

6.
J Appl Microbiol ; 132(4): 2673-2682, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34850505

RESUMO

AIM: During several local COVID-19 outbreaks in China in 2020, SARS-CoV-2 or its RNA was isolated or detected from frozen food or packages, revealing the lack of effective disinfection measures in the frozen food chain and risk of transmission. We explored the possibility that disinfectant plus antifreeze could be delivered as thermal fog to realize effective disinfection at subzero temperatures. METHODS AND RESULTS: We selected two disinfectant-antifreeze combinations, didecyl dimethyl ammonium bromide (DDAB) - propylene glycol (PPG) and peracetic acid (PAA) - triethylene glycol (TEG), and each combination is used with a custom-optimized thermal fogging machine. The two fogs were tested in -20°C freezer warehouses for their disinfection efficacy against a coronavirus porcine epidemic diarrhoea virus (PEDV) field strain, a swine influenza virus (SIV) field strain, and three indicator bacteria, Escherichia coli, Staphylococcus aureus and Bacillus subtilis endospores. At -20°C, the DDAB-PPG or PAA-TEG thermal fogs settle within 3.5 to 4.5 h and effectively inactivated PEDV with median tissue culture infective dose of 10-3.5 0.1 ml-1 and SIV-H1N1 with hemagglutination titre of 26  ml-1 within 15-60 min. DDAB-PPG could inactivate S. aureus and E. coli vegetative cells (106  cfu ml-1 ) within 15-60 min but not effective on B. subtilis spores, while PAA-TEG could disinfect B. subtilis spores more effectively than for S. aureus and E. coli. CONCLUSIONS: We showed that a practical subzero temperature disinfection technology was effective in killing enveloped viruses and vegetative bacteria or bacterial spores. DDAB-PPG or PAA-TEG thermal fogging may be a practical technology for cold-chain disinfection. SIGNIFICANCE AND IMPACT OF THE STUDY: This subzero temperature disinfection technology could help to meet the urgent public health need of environmental disinfection in frozen food logistics against pandemic and other potential pathogens and to enhance national and international biosecurity.


Assuntos
COVID-19 , Desinfetantes , Vírus da Influenza A Subtipo H1N1 , Animais , Bacillus subtilis , Desinfetantes/farmacologia , Desinfecção/métodos , Escherichia coli , Ácido Peracético/farmacologia , SARS-CoV-2 , Staphylococcus aureus , Suínos , Tempo (Meteorologia)
7.
J Infect Dis ; 202(9): 1338-46, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20854176

RESUMO

To study the effect of NS1 eIF4GI binding domain on virulence and pathogenicity of H5N1 influenza A virus, 5 recombinant H5N1 viruses encoding eIF4GI binding domain-truncated NS1 proteins and parental NS1 (NS1­wt) were generated by an 8­plasmid-based reverse genetics system. The results indicated that the recombinants with the addition of 5­amino acid and the deletion position of 85-89 in NS1­wt were attenuated in replication in vitro and in vivo, compared with the recombinant wild­type virus rNS1­wt, whereas the deletion position 85-94 or the entire eIF4GI binding domain in NS1­wt displayed a significantly attenuated phenotype in chicken and mice. We also showed that the eIF4GI binding domain-truncated mutants were impaired in their ability to inhibit interferon production in vitro, and they did not replicate as efficiently as the parental recombinant strain in embryonated hen eggs, in Madin ­Darby Canine Kidney cells, or in vivo in chickens and in a mouse model. Therefore, these attenuated NS1­truncated viruses may have a great potential as live attenuated vaccine candidates against H5N1 influenza A virus.


Assuntos
Fator de Iniciação Eucariótico 4G/metabolismo , Virus da Influenza A Subtipo H5N1/patogenicidade , Proteínas não Estruturais Virais/genética , Fatores de Virulência/genética , Animais , Linhagem Celular , Embrião de Galinha , Galinhas , Cães , Feminino , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/patologia , Influenza Aviária/virologia , Interferons/antagonistas & inibidores , Interferons/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/patologia , Infecções por Orthomyxoviridae/virologia , Ligação Proteica , Deleção de Sequência , Proteínas não Estruturais Virais/metabolismo , Virulência , Fatores de Virulência/metabolismo , Replicação Viral
8.
Microb Pathog ; 48(3-4): 103-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19944142

RESUMO

Streptococcus suis is an important swine and human pathogen, and also an emerging zoonotic agent. A surface-associated subtilisin-like serine protease (SspA) of S. suis was identified by screening a genomic expression library as fragments of this protein reacted most strongly with convalescent-phase pig sera. The sspA gene is present in 29 of 33 S. suis serotypes reference strains and is expressed on the surface of S. suis. Relative real-time quantitative PCR assay demonstrated that sspA mRNA expression in vivo was several thousand fold of that in vitro. A sspA(-) mutant was generated from a S. suis serotype 2 strain SC19 by allelic exchange. The mutant was not different from the wild type strain in subcellular structures and in hemolytic phenotype. However, the virulence of the sspA(-) mutant was markedly lower than the wild type in pigs as demonstrated in experimental infections. These data indicated that the surface-associated protein SspA is a conserved virulence factor of S. suis and is involved in the pathogenesis of S. suis.


Assuntos
Parede Celular/enzimologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/enzimologia , Streptococcus suis/patogenicidade , Subtilisina/genética , Subtilisina/metabolismo , Doenças dos Suínos/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Deleção de Genes , Perfilação da Expressão Gênica , Genes Bacterianos , Humanos , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Mutagênese Insercional , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Infecções Estreptocócicas/microbiologia , Streptococcus suis/isolamento & purificação , Subtilisina/deficiência , Análise de Sobrevida , Suínos , Virulência
9.
PLoS One ; 4(7): e6277, 2009 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-19609439

RESUMO

The variation of highly pathogenic avian influenza H5N1 virus results in gradually increased virulence in poultry, and human cases continue to accumulate. The neuraminidase (NA) stalk region of influenza virus varies considerably and may associate with its virulence. The NA stalk region of all N1 subtype influenza A viruses can be divided into six different stalk-motifs, H5N1/2004-like (NA-wt), WSN-like, H5N1/97-like, PR/8-like, H7N1/99-like and H5N1/96-like. The NA-wt is a special NA stalk-motif which was first observed in H5N1 influenza virus in 2000, with a 20-amino acid deletion in the 49(th) to 68(th) positions of the stalk region. Here we show that there is a gradual increase of the special NA stalk-motif in H5N1 isolates from 2000 to 2007, and notably, the special stalk-motif is observed in all 173 H5N1 human isolates from 2004 to 2007. The recombinant H5N1 virus with the special stalk-motif possesses the highest virulence and pathogenicity in chicken and mice, while the recombinant viruses with the other stalk-motifs display attenuated phenotype. This indicates that the special stalk-motif has contributed to the high virulence and pathogenicity of H5N1 isolates since 2000. The gradually increasing emergence of the special NA stalk-motif in H5N1 isolates, especially in human isolates, deserves attention by all.


Assuntos
Virus da Influenza A Subtipo H5N1/patogenicidade , Neuraminidase/fisiologia , Sequência de Aminoácidos , Animais , Embrião de Galinha , Feminino , Humanos , Virus da Influenza A Subtipo H5N1/enzimologia , Virus da Influenza A Subtipo H5N1/crescimento & desenvolvimento , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Neuraminidase/química , Ensaio de Placa Viral , Virulência
10.
Mol Immunol ; 46(11-12): 2210-7, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19446339

RESUMO

Baculovirus has emerged recently as a novel and attractive gene delivery vehicle for mammalian cells. In this study, baculovirus pseudotyped with vesicular stomatitis virus glycoprotein was used as a vector to express the hemagglutinin (HA) protein of highly pathogenic H5N1 avian influenza virus, A/Chicken/Hubei/327/2004 (HB/327). The resultant recombinant baculovirus (BV-G-HA) mediated gene delivery and HA expression efficiently in mammalian cells. Mice immunized with 1 x 10(9)PFU of BV-G-HA developed significantly higher levels of H5-specific antibodies and cellular immunity than those that received 100 microg of DNA vaccines expressing HA, and were completely protected from lethal challenge with HB/327. Different vaccination doses were further tested in chickens, and these experiments demonstrated that 1 x 10(8)PFU of BV-G-HA offered complete protection from challenge with 100 LD(50) of HB/327. These data indicate that the pseudotype baculovirus-mediated vaccine could be utilized as an alternative strategy against the pandemic spread of H5N1 influenza virus.


Assuntos
Baculoviridae/genética , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Animais , Linhagem Celular , Galinhas , Cricetinae , Cães , Vetores Genéticos , Glicoproteínas de Hemaglutininação de Vírus da Influenza/biossíntese , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Imunidade Ativa , Virus da Influenza A Subtipo H5N1/genética , Influenza Aviária/imunologia , Influenza Aviária/prevenção & controle , Camundongos , Infecções por Orthomyxoviridae/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia , Vesiculovirus/genética
11.
Virus Genes ; 38(2): 295-301, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19224353

RESUMO

Based on the understanding that the analysis on unique short (US) region of duck enteritis virus (DEV) might contribute to the recognition of the molecular characterization and the evolution of DEV, in the study, a 5,121 bp fragment, which contained three genes encoding complete US10, unique short region open reading frame (SORF) 3, and US2 proteins, was amplified from the DEV (C-KCE) genome. The transcription orientation of the US10 and SORF3 was in a tail-to-tail way, and the SORF3 and US2 was the same. Potential core promoters and polyadenylation (poly(A)) sites were predicted for US10, SORF3, and US2 and further confirmed by polymerase chain reaction. Phylogenetic analysis for the three complete coding sequences showed that DEV was more closely related to avian herpesviruses, especially to Mardivirus, and should be classified to a separate genus of the Alphaherpesvirinae subfamily.


Assuntos
Alphaherpesvirinae/genética , Doenças das Aves/virologia , Enterite/veterinária , Infecções por Herpesviridae/veterinária , Proteínas Virais/genética , Alphaherpesvirinae/classificação , Alphaherpesvirinae/isolamento & purificação , Animais , Sequência de Bases , DNA Viral/química , DNA Viral/genética , Patos , Enterite/virologia , Ordem dos Genes , Infecções por Herpesviridae/virologia , Mardivirus/genética , Dados de Sequência Molecular , Filogenia , Regiões Promotoras Genéticas , Sinais de Poliadenilação na Ponta 3' do RNA , Análise de Sequência de DNA , Homologia de Sequência , Transcrição Gênica
12.
Virus Genes ; 38(2): 263-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19137421

RESUMO

In this report, an H5N1 avian influenza virus, A/duck/Hubei/hangmei01/2006, which could lead to acute disease including neurovirulence and mortality in ducks, was isolated in brains of domestic ducks in spring of 2006. Molecular characterization of the genes revealed that this virus harbored the common characteristics of a highly pathogenic avian influenza (HPAI). Phylogenetic analyses demonstrated that this virus was a member of the Fujian-like virus sublineage. All eight genes except NA and PB2 had the closest genetic relatives to the human influenza virus A/China/GD01/2006. It might indicate that the virus A/duck/Hubei/hangmei01/2006 originated from southern China, resulting from the wild bird migration or poultry transportation, and indicate that more surveillance upon evolution and transmission of influenza viruses in ducks was urgent.


Assuntos
Encéfalo/patologia , Encéfalo/virologia , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/virologia , Animais , China , Análise por Conglomerados , Patos , Virus da Influenza A Subtipo H5N1/classificação , Virus da Influenza A Subtipo H5N1/isolamento & purificação , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Virulência
13.
Vet Microbiol ; 137(1-2): 24-30, 2009 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-19136223

RESUMO

A sandwich ELISA test using AIV H5 subtype specific monoclonal antibody (clone 2H4) to an epitope of hemagglutinin protein has been developed. The monoclonal antibody was used to capture the antigen from clinical samples (swabs and tissues). Captured antigens from clinical samples were detected using polyclonal sera, purified AIV H5N1 particles were titrated in the sandwich ELISA and the limit of detection was determined to be approximately 1.0 ng of influenza viral protein in virus preparations. Fifteen AIV strains of H1-H15 subtypes and some other pathogens were tested by this system, and the test is specific to H5 subtype viruses as it failed to detect other AIV subtype viruses and other pathogens. Varieties of clinical samples originating from laboratory experiments (n=382) and from fields (n=288) were employed to test the efficacy of DAS-ELISA test. The test compared very well with the traditional method for detection of influenza virus: virus isolation (VI) in embryonated chicken eggs. In comparison to virus isolation the sensitivity and specificity of sandwich ELISA were found to be 98.6% and 97.6% respectively. In addition, the DAS-ELISA was used to test samples of experimentally infected birds and clinical samples obtained from central China in 2005. The assay proved to be sensitive and specific for the rapid detection of AIV H5 subtype virus form the tissues and swabs in infected animals.


Assuntos
Anticorpos Monoclonais/imunologia , Ensaio de Imunoadsorção Enzimática/veterinária , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Virus da Influenza A Subtipo H5N1/genética , Animais , Aves , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos , Influenza Aviária/sangue , Influenza Aviária/diagnóstico , Influenza Aviária/virologia , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Sensibilidade e Especificidade
14.
J Virol Methods ; 154(1-2): 99-103, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18812190

RESUMO

An H5N1 avian influenza virus (AIV) hemagglutinin (HA) protein pseudotyped lentivirus, HIV/H5-HA, was generated, characterized in vitro and evaluated for its ability to induce protective immunity against virulent wild type AIV in mice. The HIV/H5-HA virus was able to infect 293T, BHK, Vero, PK-15, MDCK cells but not IBRS-2 cells and therefore demonstrated cell tropism similar to the wild type AIV. HIV/H5-HA agglutinated chicken erythrocytes and cell entry was blocked by ammonium chloride, indicating that the process is pH-dependent. In mice, HIV/H5-HA immunization resulted in low levels of virus in the lungs, elicited high levels of AIV HA-specific antibody as indicated by the hemagglutination inhibition (HI) test, and the antibody induction was both earlier and with a higher titer than that induced by the inactivated AIV vaccine. These results confirmed the roles played by HA in AIV infection and immunogenicity and suggested that the pseudotyped lentivirus is a good model for studying the functions of AIV HA.


Assuntos
HIV/genética , Hemaglutininas Virais/imunologia , Hemaglutininas Virais/metabolismo , Virus da Influenza A Subtipo H5N1/genética , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Animais , Anticorpos Antivirais/sangue , Peso Corporal , Linhagem Celular , Feminino , HIV/imunologia , Testes de Inibição da Hemaglutinação , Virus da Influenza A Subtipo H5N1/imunologia , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/prevenção & controle
15.
Virus Genes ; 36(1): 79-83, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18027082

RESUMO

Full-length eight gene segments of avian influenza virus A/duck/Hubei/W1/2004(H9N2) (Dk/Hub/W1/04) were amplified by RT-PCR and completely sequenced. Phylogenetic analysis revealed that Dk/Hub/W1/04 was derived from A/Duck/HongKong/Y280/97, not displaying direct evolutional relationship with A/Quail/HongKong/G1/97 or Hubei H5N1 viruses. Meanwhile, Dk/Hub/W1/04 was found highly related to recent three chicken isolates. The connecting peptide of HA and the deletion in NA stalk were consistent with three chicken isolates, and the number of potential glycosylation site on the HA and NA also was similar or identical to the three chicken isolates. These findings suggested that Dk/Hub/W1/04 is likely to transmit back to ducks from chickens.


Assuntos
Evolução Molecular , Genes Virais , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/epidemiologia , Influenza Aviária/virologia , Neuraminidase/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Aves/virologia , Galinhas/virologia , China/epidemiologia , Patos/virologia , Genoma Viral , Glicosilação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Vírus da Influenza A Subtipo H9N2/classificação , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Dados de Sequência Molecular , Neuraminidase/química , Filogenia , Alinhamento de Sequência
16.
Antiviral Res ; 76(2): 186-93, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17719657

RESUMO

RNA interference (RNAi) is a powerful tool to silence gene expression. Small interfering RNA (siRNA)-induced RNA degradation has been recently used as an antivirus agent to inhibit specific virus replication. Here, we showed that several siRNAs specific for conserved regions of influenza virus matrix (M2) and nucleocapsid protein (NP) genes could effectively inhibit expression of the corresponding viral protein. We also evaluated the antiviral potential of these siRNAs targeting M2 and NP of H5N1 avian influenza virus (AIV), which are essential to viral replication. We investigated the inhibitory effect of M2-specific siRNAs and NP-specific siRNAs on influenza A virus (H5N1, H1N1 and H9N2) replication in Madin-Darby canine kidney (MDCK) cells and BALB/c mice. The results showed that treatment with these siRNAs could specifically inhibit influenza A virus replication in MDCK cells (0.51-1.63 TCID(50) reduction in virus titers), and delivery of pS-M48 and pS-NP1383 significantly reduced lung virus titers in the infected mice (16-50-fold reduction in lung virus titers) and partially protected the mice from lethal influenza virus challenge (a survival rate of 4/8 for H1N1 virus-infected mice and 2/8 for H5N1 virus infected mice). Moreover, the treatment of pS-M48 and pS-NP1383 could suppress replication of different subtypes of influenza A viruses, including a H5N1 highly pathogenic avian isolate strain. The results provided a basis for further development of siRNA for prophylaxis and therapy of influenza virus infection in humans and animals.


Assuntos
Vírus da Influenza A Subtipo H1N1/genética , Virus da Influenza A Subtipo H5N1/genética , Vírus da Influenza A Subtipo H9N2/genética , Infecções por Orthomyxoviridae/terapia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico , Animais , Peso Corporal , Linhagem Celular , Cães , Feminino , Terapia Genética/métodos , Pulmão/virologia , Camundongos , Camundongos Endogâmicos BALB C , Proteínas do Nucleocapsídeo , Nucleoproteínas/biossíntese , Nucleoproteínas/genética , Infecções por Orthomyxoviridae/genética , Proteínas de Ligação a RNA/biossíntese , Proteínas de Ligação a RNA/genética , Análise de Sobrevida , Proteínas do Core Viral/biossíntese , Proteínas do Core Viral/genética , Proteínas da Matriz Viral/biossíntese , Proteínas da Matriz Viral/genética
18.
J Vet Diagn Invest ; 19(2): 155-60, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17402609

RESUMO

A rapid and simple latex agglutination test (LAT) for the detection of avian influenza virus (AIV) subtype H5N1 in chicken allantoic fluids, tracheal swabs, and tissues was developed. Monoclonal antibodies against the hemagglutinin glycoprotein of H5N1 were covalently coupled onto the surface of carboxylated latex bead using a water-soluble carbodiimide to obtain sensitized latex particles (SLP). These SLPs strongly agglutinated in the presence of allantoic fluid containing H5N1, but not fluids containing other AIV sub-types such as HIN1, H3N2, H4N6, and H9N2. Using this LAT, the virus was detectable in tracheal swabs 24 hours to 30 days after inoculating chickens with H5N1, with detection rates ranging from 45.5 to 79.2%. Much higher rates of detection were obtained from tissues collected postmortem from H5N1 experimentally infected chickens; lung tissue yielded the highest detection rate (96.7%), followed by kidney, spleen, brain, and liver tissues (90%). Lower detection rates were achieved with heart (41.7%) and cloacal tissues (26.8%). When the LAT was compared with other detection methods, the agreement with the viral isolation, H5 antigen immunochromatographic test,and H5 real-time RT-PCR test was 93.97, 95.18, and 87.95%, respectively. The test was highly specific for H5N1 in chickens and water fowls and had sensitivity comparable to other diagnostic tests evaluated.


Assuntos
Virus da Influenza A Subtipo H5N1/isolamento & purificação , Influenza Aviária/diagnóstico , Testes de Fixação do Látex/veterinária , Alantoide/virologia , Animais , Galinhas , Virus da Influenza A Subtipo H5N1/classificação , Traqueia/virologia
19.
Mol Immunol ; 44(5): 1052-5, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16965815

RESUMO

BALB/c mice were immunized with formalin-treated influenza A/CK/Hubei/327/2004 virus. Six monoclonal antibodies specific to HA were selected, designed 1H8, 1D11, 2B7, 2C9, 2H4 and 4C9, respectively. The six Mabs probed linear epitopes by western blot assays. In ELISA additivity assays, the low additivity indexes (< or =28.3) of each pair Mabs indicated that the epitopes recognized by the six Mabs were located on the globular head of HA1. The neutralization activity of anti-HA1 Mabs and chicken polyclonal sera to various AIV H5N1 strains from different hosts was followed by virus neutralization with MDCK cells. All Mabs except 2C9 and chicken polyclonal serum showed highest neutralizing activity to lowly virulent A/Duck/XF/XFY/2004 from different phylogenetic lineage, and lowest neutralization efficiency to highly virulent A/CK/XF/XFJ/2004. For the other two highly virulent viruses, 1D11, 2H4, 4C9 and chicken polyclonal sera had higher neutralization to A/Goose/ZF/ZFE/2004 than A/CK/Hubei/327/2004, and 1H8 and 2B7 had considerable level of neutralizing efficiency to them. These findings suggested that the neutralizing antibodies showed lower neutralization efficiency to highly virulent virus strains than lowly virulent virus strains and strong cross-neutralizing reaction between virus strains located in different phylogenetic lineages. Moreover, the neutralizing Mabs could more efficiently neutralize AIV H5N1 strains from the natural hosts generally, such as waterfowl.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Antivirais/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Animais , Linhagem Celular Tumoral , Galinhas , Patos , Feminino , Gansos , Hemaglutininas Virais/imunologia , Imunização , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização
20.
Avian Dis ; 50(2): 264-8, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16863078

RESUMO

A latex agglutination test (LAT) was developed for rapid detection of antibodies to H5 avian influenza viruses (AIVs). The hemagglutinin protein of H5 AIV was covalently linked to carboxylated latex by ethyl-dimethyl-amino-propyl carbodiimide to prepare the sensitized latex beads. The LAT was evaluated with the hemagglutination inhibition (HI) assay as the reference test. The H5-LAT showed a sensitivity of 87.0% and specificity of 88.9% in detecting 126 serum samples from experimentally infected chickens and a sensitivity of 82.5% and specificity of 86% in detecting 587 field chicken serum samples from mostly vaccinated chickens. The agreement ratio between H5-LAT and HI was found to be 87.3% and 83.1% for the two groups of samples, respectively. Difficulty with background agglutination in stored chicken sera was overcome by serum pretreatment with either dried chicken liver powder or dilution buffer containing detergent Tween-20. The H5-LAT has advantages over a previously reported whole-virus LAT in terms of biosafety in preparation, chemical stability, and higher specificity. It is a rapid and simple test suitable for field monitoring of antibodies to H5-type AIV.


Assuntos
Anticorpos Antivirais/análise , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A/imunologia , Influenza Aviária/diagnóstico , Testes de Fixação do Látex/métodos , Animais , Antígenos Virais/análise , Antígenos Virais/imunologia , Aves/imunologia , Aves/virologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/análise , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/virologia , Proteínas Recombinantes , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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