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1.
Eur Arch Otorhinolaryngol ; 281(2): 683-691, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37552281

RESUMO

PURPOSE: To investigate 2-year post-operative hearing performance, safety, and patient-reported outcomes of hearing-impaired adults treated with the Osia® 2 System, an active osseointegrated bone-conduction hearing implant that uses piezoelectric technology. METHODS: A prospective, multicenter, open-label, single-arm, within-subject clinical study conducted at three tertiary referral clinical centers located in Melbourne, Sydney and Hong Kong. Twenty adult recipients of the Osia 2 System were enrolled and followed up between 12 and 24 months post-implantation: 17 with mixed or conductive hearing loss and 3 with single-sided sensorineural deafness. Safety data, audiological thresholds, speech recognition thresholds in noise, and patient-reported outcomes were collected and evaluated. In addition, pre-and 6-month post-implantation data were collected retrospectively for this recipient cohort enrolled into the earlier study (ClinicalTrials.gov NCT04041700). RESULTS: Between 6- and 24-month follow-up, there was no statistically significant change in free-field hearing thresholds or speech reception thresholds in noise (p = > 0.05), indicating that aided improvements were maintained up to 24 months of follow-up. Furthermore, improvements in health-related quality of life and daily hearing ability, as well as clinical and subjective measures of hearing benefit remained stable over the 24-month period. No serious adverse events were reported during extended follow-up. CONCLUSIONS: These study results provide further evidence to support the longer term clinical safety, hearing performance, and patient-related benefits of the Osia 2 System in patients with either a conductive hearing loss, mixed hearing loss, or single-sided sensorineural deafness. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04754477. First posted: February 15, 2021.


Assuntos
Surdez , Auxiliares de Audição , Perda Auditiva Condutiva-Neurossensorial Mista , Perda Auditiva Neurossensorial , Perda Auditiva , Percepção da Fala , Adulto , Humanos , Perda Auditiva Condutiva/cirurgia , Perda Auditiva Condutiva-Neurossensorial Mista/cirurgia , Seguimentos , Estudos Prospectivos , Qualidade de Vida , Estudos Retrospectivos , Audição , Condução Óssea , Medidas de Resultados Relatados pelo Paciente
2.
Folia Phoniatr Logop ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37935141

RESUMO

INTRODUCTION: This study aims at exploring the feasibility of applying a computer-based language test to young children aged 2-4 years. METHODS: Thirty-two Cantonese-speaking children, aged 2-4 years, were recruited from local kindergartens. All participants underwent assessment using both the computer-based and paper-pencil versions of the Macau Cantonese Language Screening Scale for Preschool Children, following a crossover study design. A short break of 15-30 minutes was provided between the two assessments. The data were analysed at three levels: the overall test, subcategory, and individual item levels. At the overall test and subcategory levels, data were analysed using the paired samples t-test and ICC. At the item level, the percentage of agreement and Cohen's kappa value were selected to assess the agreement of the two test formats. RESULTS: Excellent agreement was found for the overall test level, and good agreement was observed for four of the five subcategories. At the individual item level, 28 of the 35 items showed more than 80% agreement, and 16 items showed substantial to almost perfect agreement. CONCLUSION: These results suggest that the two test formats give similar total scores and subcategory scores for children aged 2-4. For children older than 2 years, 6 months, the agreement for matching items is as high as 83.68% (1318/1575). The computer-based test is thus highly recommended for this group of children. For children younger than 2 years, 6 months, a modified computer-based test is suggested to accommodate their needs.

3.
J Infect Dis ; 205(11): 1646-53, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22457284

RESUMO

Like αß T cells, human γδ T cells also have different subsets with distinct characteristics. Whether human Vγ9Vδ2 T cells have functionally different subsets in response to influenza A (fluA) viruses remains unknown. In this study, we show for the first time that both central (CD45RA(-)CD27(+)) and effector (CD45RA(-)CD27(-)) memory Vγ9Vδ2 T cells have similar levels of immediate interferon (IFN) γ and cytotoxic responses to human and avian fluA virus-infected cells. In contrast, CD56(+) Vγ9Vδ2 T cells have significantly higher cytotoxicity against fluA virus-infected cells compared with their CD56(-) counterparts, whereas both subsets have similar IFN-γ responses. We further demonstrate that the CD16-dependent degranulation pathway, but not antibody-dependent cell-mediated cytotoxicity, contribute to the superior cytotoxicity of CD56(+) Vγ9Vδ2 T cells. Our study provides further evidence for the phenotypic and functional characterization of human Vγ9Vδ2 T-cell subsets during fluA virus infection and may help improve the γδ T-cell-based immunotherapy for viral infection.


Assuntos
Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Influenza Humana/virologia , Subpopulações de Linfócitos T/imunologia , Antígeno CD56/análise , Degranulação Celular/imunologia , Proteínas Ligadas por GPI/análise , Humanos , Imunofenotipagem , Interferon gama/imunologia , Interferon gama/metabolismo , Antígenos Comuns de Leucócito/análise , Receptores de IgG/análise , Linfócitos T Citotóxicos/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/análise
4.
Am J Audiol ; 32(2): 379-390, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37080240

RESUMO

PURPOSE: This study investigated to what extent residual hearing and rehabilitation options (e.g., hearing aids [HAs]) affect the auditory cortex in children with hearing loss. METHOD: Twenty-one children with bilateral congenital sensorineural hearing loss who were candidates for cochlear implantation were recruited. Voxel-based morphometry analysis was conducted to assess the gray matter (GM) volume in the auditory cortex. Children's residual hearing was measured by pure-tone audiometry at different frequencies. Multiple linear regression models were conducted to examine the effects of residual hearing and the use of HAs on GM volume in the auditory cortex with the control of age and gender. RESULTS: Children with more residual hearing at high frequencies had larger GM volume ratio (corrected by total intracranial volume) in the left Heschl's gyrus (r = -.545, p = .013). An interaction effect between residual hearing and the use of HAs suggested that the effect of residual hearing on GM ratio was moderated by the use of HAs (ß = -.791, p = .020). Compared with children with less residual hearing, children who had more residual hearing benefited more from longer use of HAs in terms of a larger GM ratio. CONCLUSIONS: Our preliminary findings highlight the impact of residual hearing on the neuroanatomy of the auditory cortex in children with hearing loss. Moreover, our results call for more auditory input via HAs for children with more residual hearing to preserve the auditory cortex before cochlear implantation. For children with less residual hearing who might receive limited benefit from HAs, an early cochlear implant would be necessary.


Assuntos
Córtex Auditivo , Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva Neurossensorial , Perda Auditiva , Humanos , Criança , Surdez/reabilitação , Audição , Perda Auditiva Neurossensorial/reabilitação
6.
J Virol ; 85(19): 10109-16, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21752902

RESUMO

γδ T cells are essential constituents of antimicrobial and antitumor defenses. We have recently reported that phosphoantigen isopentenyl pyrophosphate (IPP)-expanded human Vγ9Vδ2 T cells participated in anti-influenza virus immunity by efficiently killing both human and avian influenza virus-infected monocyte-derived macrophages (MDMs) in vitro. However, little is known about the noncytolytic responses and trafficking program of γδ T cells to influenza virus. In this study, we found that Vγ9Vδ2 T cells expressed both type 1 cytokines and chemokine receptors during influenza virus infection, and IPP-expanded cells had a higher capacity to produce gamma interferon (IFN-γ). Besides their potent cytolytic activity against pandemic H1N1 virus-infected cells, IPP-activated γδ T cells also had noncytolytic inhibitory effects on seasonal and pandemic H1N1 viruses via IFN-γ but had no such effects on avian H5N1 or H9N2 virus. Avian H5N1 and H9N2 viruses induced significantly higher CCL3, CCL4, and CCL5 production in Vγ9Vδ2 T cells than human seasonal H1N1 virus. CCR5 mediated the migration of Vγ9Vδ2 T cells toward influenza virus-infected cells. Our findings suggest a novel therapeutic strategy of using phosphoantigens to boost the antiviral activities of human Vγ9Vδ2 T cells against influenza virus infection.


Assuntos
Vírus da Influenza A Subtipo H1N1/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/análise , Subpopulações de Linfócitos T/imunologia , Células Cultivadas , Citocinas/biossíntese , Citotoxicidade Imunológica , Hemiterpenos/metabolismo , Humanos , Fatores Imunológicos/metabolismo , Virus da Influenza A Subtipo H5N1/imunologia , Vírus da Influenza A Subtipo H9N2/imunologia , Compostos Organofosforados/metabolismo , Subpopulações de Linfócitos T/química
7.
Front Pharmacol ; 13: 844730, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35431960

RESUMO

Background: Tinnitus is a common problem worldwide. There is still no effective method to cure it. Traditional Chinese medicine (TCM) may be a potentially effective treatment approach for tinnitus. However, there is still no clinical trial with scientifically rigorous methodology to evaluate the treatment effect of TCM for tinnitus. Therefore, we propose a pilot study to inform the feasibility of a future full-scale RCT to establish the efficacy of TCM formula for tinnitus. Objectives: The aim of this study is to determine the feasibility of a full-scale RCT and explore whether a TCM formula (BHT) has an additional effect on improving tinnitus when compared to informative counseling alone. Design: An assessor-blinded, randomized, controlled clinical trial is used. Participants: Twenty-four patients with chronic subjective tinnitus will be enrolled. Interventions: The patients will be allocated randomly to receive a TCM formula (BHT, Bushen Huoxue Tongluo) and informative counseling or informative counseling alone. The oral BHT herbal granules will be taken twice per day continuously for 8 weeks. Main outcome measures: The primary outcomes include recruitment rate, intervention completion rate, and data completion rate to evaluate the feasibility. The secondary outcomes include Tinnitus Handicap Inventory, tinnitus functional index, tinnitus sensation level, self-rated visual analogue scale on tinnitus loudness and annoyance, Pittsburgh Sleep Quality Index, Hospital Anxiety and Depression Scale, and adverse event. The outcome measures will be collected at baseline, end of treatment, and 4-week follow-up. Discussion: This trial is currently ongoing and is recruiting patients. The expected study results will find some preliminary evidence about the clinical effectiveness of BHT on chronic tinnitus and will also determine if it is feasible to conduct a full-scale RCT of BHT and identify the necessary changes to the protocol if possible.

8.
J Autism Dev Disord ; 52(9): 3825-3839, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34480668

RESUMO

This study examined the early pragmatic language skills in typically developing (TD) preschool-age children, children with language impairment (LI) and children with autism spectrum disorder (ASD). Two hundred and sixty-two TD children, 73 children with LI, and 16 children with ASD were compared on early pragmatics through direct assessment (DA). Post hoc analysis revealed that children in two clinical groups displayed significant pragmatic language deficits. Children in the ASD group who were older exhibited comparable degree of impairments as their LI peers, suggesting a relatively stagnant development of pragmatic language skills in children with ASD. Findings also supported the use of DA in identifying pragmatic language deficits, which have implications for the adoption of this assessment approach in clinical settings.


Assuntos
Transtorno do Espectro Autista , Transtornos do Desenvolvimento da Linguagem , Aptidão , Criança , Pré-Escolar , Humanos , Idioma , Transtornos do Desenvolvimento da Linguagem/diagnóstico
9.
Otol Neurotol ; 43(7): 827-834, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35878640

RESUMO

OBJECTIVE: To investigate the clinical performance, safety, and patient-reported outcomes of an active osseointegrated steady-state implant system that uses piezoelectric technology. STUDY DESIGN: A prospective, multicenter, open-label, single-arm, within-subject clinical investigation. SETTING: Three tertiary referral clinical centers located in Melbourne, Sydney, and Hong Kong. PATIENTS: Twenty-nine adult subjects, 24 with mixed hearing loss or conductive hearing loss and 5 with single-sided sensorineural deafness. INTERVENTION: Implantation with the Cochlear Osia 2 System. MAIN OUTCOME MEASURES: Audiological threshold evaluation and speech recognition in quiet and in noise. Patient satisfaction and safety. RESULTS: At 6-month follow-up after surgery, a mean improvement in pure-tone average of 26.0 dB hearing level and a mean improvement of 8.8 dB signal-to-noise ratio in speech reception threshold in noise was achieved with the investigational device as compared with the unaided situation. Usability of the investigational device was rated 71.4/100 mm for sound processor retention and 81.4/100 mm for overall comfort using a visual analog scale. CONCLUSION: These outcomes confirm the clinical safety, performance, and benefit of an innovative active transcutaneous bone conduction implant using a piezoelectric transducer design in subjects with conductive hearing loss, mixed hearing loss, or single-sided sensorineural deafness.


Assuntos
Surdez , Auxiliares de Audição , Perda Auditiva Condutiva-Neurossensorial Mista , Perda Auditiva Neurossensorial , Perda Auditiva , Percepção da Fala , Adulto , Condução Óssea , Perda Auditiva/cirurgia , Perda Auditiva Condutiva/cirurgia , Perda Auditiva Condutiva-Neurossensorial Mista/cirurgia , Perda Auditiva Neurossensorial/cirurgia , Humanos , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Resultado do Tratamento
10.
J Immunol ; 182(2): 1088-98, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19124752

RESUMO

The hyperinduction of proinflammatory cytokines and chemokines such as TNF-alpha, IFN-beta, and CCL2/MCP-1 in primary human macrophages and respiratory epithelial cells by the highly pathogenic avian influenza H5N1 is believed to contribute to the unusual severity of human H5N1 disease. Here we show that TNF-alpha, IFN-beta, and IFN-lambda1 are the key mediators directly induced by the H5N1 virus in primary human macrophages. In comparison with human influenza (H1N1), the H5N1 virus more strongly activated IFN regulatory factor 3 (IRF3). IRF3 knockdown and p38 kinase inhibition separately and in combination led to a substantial reduction of IFN-beta, IFN-lambda1, and MCP-1 but only to a partial reduction of TNF-alpha. IRF3 translocation was independent of p38 kinase activity, indicating that IRF3 and p38 kinase are distinct pathways leading to cytokine production by H5N1 virus. We conclude that IRF3 and p38 kinase separately and predominantly contribute to H5N1-mediated induction of IFN-beta, IFN-lambda1, and MCP-1 but only partly control TNF-alpha induction. A more precise identification of the differences in the regulation of TNF-alpha and IFN-beta could provide novel targets for the design of therapeutic strategies for severe human H5N1 influenza and also for treating other causes of acute respiratory distress syndrome.


Assuntos
Citocinas/biossíntese , Mediadores da Inflamação/metabolismo , Virus da Influenza A Subtipo H5N1/imunologia , Fator Regulador 3 de Interferon/fisiologia , Macrófagos/imunologia , Macrófagos/virologia , Proteínas Quinases p38 Ativadas por Mitógeno/fisiologia , Animais , Linhagem Celular , Células Cultivadas , Quimiocina CCL2/biossíntese , Cães , Humanos , Mediadores da Inflamação/fisiologia , Interferon beta/biossíntese , Interferons , Interleucinas/biossíntese , Cinética , Macrófagos/enzimologia , Macrófagos/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
11.
Int J Pediatr Otorhinolaryngol ; 72(7): 1121-9, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18485493

RESUMO

OBJECTIVE: This study aimed at developing a theoretically driven open-set speech recognition test for pediatric clinical population of cochlear implant and/or hearing aid users, with Cantonese Chinese as their first language, to track progress in speech recognition performance as an outcome measurement of their rehabilitation. METHODS: Six monosyllabic and six disyllabic word lists were generated from the Cantonese CHILDES language database, constructed according to the Neighborhood Activation Model. There were three lexically "easy" and three lexically "hard" word lists in each sub-test, with 25 items in each list. Four pediatric cochlear implant users and 10 hearing aid users, with bilateral congenital severe to profound sensorineural hearing impairment and below the age of 10, participated in the study. Their performances on word recognition and phoneme recognition with the new test lists, as well as the inter-list equivalency, inter-rater reliability, and face validity of the new materials, were investigated. RESULTS: Word recognition was higher among disyllables than monosyllables. Lexically "easy" disyllabic words were better recognized than their "hard" counterparts and the monosyllables. No significant difference was noted among the three lists in each combination of syllable structure and lexical property. High inter-rater reliability, as well as high correlation between Cantonese LNT score and a receptive vocabulary test score, were revealed. CONCLUSIONS: These newly developed test lists provided reliable information on spoken word recognition of pediatric hearing prosthesis users with severe to profound hearing impairment. Inter-list equivalency and inter-rater reliability allowed monitoring of rehabilitation progress on such specific pediatric clinical population with this new test. (255).


Assuntos
Implantes Cocleares , Auxiliares de Audição , Testes de Discriminação da Fala , Pré-Escolar , China , Feminino , Perda Auditiva Neurossensorial/reabilitação , Humanos , Masculino , Projetos Piloto , Percepção da Fala
12.
Am J Audiol ; 25(2): 142-52, 2016 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-27250898

RESUMO

PURPOSE: The purpose of this study was to describe an attempt to apply item-response theory (IRT) and the Rasch model to construction of speech-recognition tests. A set of word-recognition test items applicable to children as young as 3 years old-with any level of hearing sensitivity, with or without using hearing devices-was developed. METHOD: Test items were constructed through expert consultation and by reference to some established language corpora, validated with 121 participants with various degrees of hearing loss and 255 with typical hearing. IRT and the Rasch model were applied to evaluate item quality. RESULTS: Eighty disyllabic word items were selected in accordance with IRT. The speech-recognition abilities of the 376 young participants are reported. The IRT analyses on this set of data are also discussed. CONCLUSIONS: A new set of speech-recognition test materials in Cantonese Chinese has been developed. Construction of short equivalent lists may be performed in accordance with IRT item qualities. Clinical applications of this test tool in the particular language population are discussed.


Assuntos
Perda Auditiva/fisiopatologia , Testes Auditivos , Reconhecimento Fisiológico de Modelo/fisiologia , Percepção da Fala/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Perda Auditiva/reabilitação , Humanos , Masculino , Modelos Teóricos , Adulto Jovem
13.
J Clin Virol ; 55(3): 209-13, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22824231

RESUMO

BACKGROUND: Sequence-independent amplification of clinical specimens can lead to the identification of novel pathogens. OBJECTIVES: To identify novel viruses in human stool specimens from patients with diarrhea and to investigate the ecology and clinical significance of such viruses. STUDY DESIGN: Nucleic acid extracted from stool specimens from patients with diarrhea with no known etiology were subjected to random PCR amplification and Roche/454 pyrosequencing. Novel viruses identified were genetically and epidemiologically characterized. RESULTS: Four gyroviruses, chicken anemia virus (CAV), human gyrovirus (HGV)/avian gyrovirus 2 (AGV2), gyrovirus 3 (GyV3) and a novel gyrovirus (tentatively designated as gyrovirus 4 (GyV4)) were identified in human stool specimens. GyV4, as well as CAV and AGV2/HGV were also detected in chicken skin and meat used for human consumption. CONCLUSIONS: A novel gyrovirus (GyV4) was identified in human stool and in chicken meat sold for human consumption. This virus was phylogenetically distinct from previously reported gyroviruses in chicken and humans (chicken anemia virus, human gyrovirus, avian gyrovirus 2 and recently reported gyrovirus 3). The epidemiology and pathogenesis of this virus in humans and in chicken needs to be further investigated.


Assuntos
Infecções por Circoviridae/virologia , Fezes/virologia , Gyrovirus/classificação , Gyrovirus/isolamento & purificação , Carne/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Galinhas , Criança , Pré-Escolar , Análise por Conglomerados , DNA Viral/química , DNA Viral/genética , Diarreia/virologia , Feminino , Gyrovirus/genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Adulto Jovem
14.
J Exp Med ; 208(7): 1511-22, 2011 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-21708931

RESUMO

There are few antiviral drugs for treating influenza, and the emergence of antiviral resistance has further limited the available therapeutic options. Furthermore, antivirals are not invariably effective in severe influenza, such as that caused by H5N1 viruses. Thus, there is an urgent need to develop alternative therapeutic strategies. Here, we show that human Vγ9Vδ2 T cells expanded by the aminobisphosphonate pamidronate (PAM) kill influenza virus-infected cells and inhibit viral replication in vitro. In Rag2(-/-)γc(-/-) immunodeficient mice reconstituted with human peripheral mononuclear cells (huPBMCs), PAM reduces disease severity and mortality caused by human seasonal H1N1 and avian H5N1 influenza virus, and controls the lung inflammation and viral replication. PAM has no such effects in influenza virus-infected Rag2(-/-)γc(-/-) mice reconstituted with Vγ9Vδ2 T cell-depleted huPBMCs. Our study provides proof-of-concept of a novel therapeutic strategy for treating influenza by targeting the host rather than the virus, thereby reducing the opportunity for the emergence of drug-resistant viruses. As PAM has been commonly used to treat osteoporosis and Paget's disease, this new application of an old drug potentially offers a safe and readily available option for treating influenza.


Assuntos
Antivirais/farmacologia , Difosfonatos/farmacologia , Infecções por Orthomyxoviridae/tratamento farmacológico , Infecções por Orthomyxoviridae/imunologia , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/imunologia , Animais , Citotoxicidade Imunológica , Interações Hospedeiro-Parasita/efeitos dos fármacos , Interações Hospedeiro-Parasita/imunologia , Humanos , Vírus da Influenza A Subtipo H1N1 , Virus da Influenza A Subtipo H5N1 , Influenza Humana/tratamento farmacológico , Influenza Humana/imunologia , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/transplante , Pulmão/efeitos dos fármacos , Pulmão/patologia , Pulmão/virologia , Depleção Linfocítica , Camundongos , Camundongos Knockout , Infecções por Orthomyxoviridae/patologia , Pamidronato , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Transplante Heterólogo , Replicação Viral/efeitos dos fármacos
15.
Influenza Res Treat ; 2010: 489213, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-23074648

RESUMO

The protective efficacy of a subunit avian influenza virus H5 vaccine based on recombinant baculovirus expressed H5 haemagglutinin antigen and an inactivated H5N2 avian influenza vaccine combined with a marker antigen (tetanus toxoid) was compared with commercially available inactivated H5N2 avian influenza vaccine in young ducks. Antibody responses, morbidity, mortality, and virus shedding were evaluated after challenge with a Vietnamese clade 1 H5N1 HPAI virus [A/VN/1203/04 (H5N1)] that was known to cause a high mortality rate in ducks. All three vaccines, administered with water-in-oil adjuvant, provided significant protection and dramatically reduced the duration and titer of virus shedding in the vaccinated challenged ducks compared with unvaccinated controls. The H5 subunit vaccine was shown to provide equivalent protection to the other two vaccines despite the H5 antibody responses in subunit vaccinated ducks being significantly lower prior to challenge. Ducks vaccinated with the H5N2 marker vaccine consistently produced antitetanus toxoid antibody. The two novel vaccines have attributes that would enhance H5N1 avian influenza surveillance and control by vaccination in small scale and village poultry systems.

16.
J Infect Dis ; 193(7): 945-53, 2006 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-16518756

RESUMO

Severe human disease associated with influenza A H5N1 virus was first detected in Hong Kong in 1997. Its recent reemergence in Asia and high associated mortality highlight the need to understand its pathogenesis. We investigated the roles of death receptor ligands (DRLs) in H5N1 infection. Significant up-regulation of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) and TNF-alpha, but not Fas ligand (FasL) mRNA, was detected in human monocyte-derived macrophages (MDMs) infected with avian influenza viruses A/Hong Kong/483/97 (H5N1/97) or its precursor, A/Quail/Hong Kong/G1/97. H5N1/97-infected MDMs exhibited the strongest induction of apoptosis in Jurkat T cells, and it could be reduced by TRAIL-receptor 2 blocking antibody. Furthermore, influenza virus infection enhanced the sensitivity of Jurkat T cells to apoptosis induced by TNF-alpha, TRAIL, and FasL. Our data suggested that functional TRAIL produced by influenza virus-infected MDMs was related to their cytotoxicity and that the enhanced sensitization to DRL-induced apoptosis detected in avian influenza may contribute to disease pathogenesis.


Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Apoptose , Virus da Influenza A Subtipo H5N1/patogenicidade , Macrófagos/virologia , Glicoproteínas de Membrana/biossíntese , Linfócitos T/citologia , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Reguladoras de Apoptose/genética , Caspase 3 , Caspases/análise , Proteína Ligante Fas , Expressão Gênica , Humanos , Células Jurkat , Glicoproteínas de Membrana/genética , RNA Mensageiro/análise , Receptores do Ligante Indutor de Apoptose Relacionado a TNF , Receptores do Fator de Necrose Tumoral/antagonistas & inibidores , Ligante Indutor de Apoptose Relacionado a TNF , Fator de Necrose Tumoral alfa/genética , Fatores de Necrose Tumoral/biossíntese , Fatores de Necrose Tumoral/genética
17.
J Infect Dis ; 194(1): 61-70, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16741883

RESUMO

In 1997, avian influenza virus H5N1 was transmitted directly from chicken to human and resulted in a severe disease that had a higher mortality rate in adults than in children. The characteristic mononuclear leukocyte infiltration in the lung and the high inflammatory response in H5N1 infection prompted us to compare the chemokine responses between influenza virus-infected adult and neonatal monocyte-derived macrophages (MDMs). The effects of avian influenza virus A/Hong Kong/483/97 (H5N1) (H5N1/97), its precursor A/Quail/Hong Kong/G1/97 (H9N2) (H9N2/G1), and human influenza virus A/Hong Kong/54/98 (H1N1) (H1N1/98) were compared. Significantly higher expression of CCL2, CCL3, CCL5, and CXCL10 was induced by avian influenza viruses than by human influenza virus. Moreover, the increase in CCL3 expression in H5N1/97-infected adult MDMs was significantly higher than that in neonatal MDMs. Enhanced expression of CCR1 and CCR5 was found in avian virus-infected adult MDMs. The strong induction of chemokines and their receptors by avian influenza viruses, particularly in adult MDMs, may account for the severity of H5N1 disease.


Assuntos
Quimiocinas/biossíntese , Vírus da Influenza A Subtipo H1N1/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Vírus da Influenza A Subtipo H9N2/imunologia , Macrófagos/imunologia , Receptores de Quimiocinas/biossíntese , Adulto , Fatores Etários , Animais , Aves , Células Cultivadas , Quimiocinas/genética , Quimiocinas/imunologia , Sangue Fetal/citologia , Regulação Viral da Expressão Gênica/imunologia , Humanos , Recém-Nascido , Vírus da Influenza A Subtipo H1N1/patogenicidade , Vírus da Influenza A Subtipo H1N1/fisiologia , Virus da Influenza A Subtipo H5N1/patogenicidade , Virus da Influenza A Subtipo H5N1/fisiologia , Vírus da Influenza A Subtipo H9N2/patogenicidade , Vírus da Influenza A Subtipo H9N2/fisiologia , Influenza Aviária/imunologia , Influenza Humana/imunologia , Macrófagos/citologia , Macrófagos/virologia , Nucleoproteínas/metabolismo , Receptores de Quimiocinas/genética , Receptores de Quimiocinas/imunologia , Fatores de Tempo , Regulação para Cima/imunologia , Replicação Viral
18.
J Virol ; 79(12): 7819-26, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15919935

RESUMO

The pathogenesis of severe acute respiratory syndrome (SARS) remains unclear. Macrophages are key sentinel cells in the respiratory system, and it is therefore relevant to compare the responses of human macrophages to infections with the SARS coronavirus (SARS-CoV) and other respiratory viruses. Primary human monocyte-derived macrophages were infected with SARS-CoV in vitro. Virus replication was monitored by measuring the levels of positive- and negative-strand RNA, by immunofluorescence detection of the SARS-CoV nucleoprotein, and by titration of the infectious virus. The gene expression profiles of macrophages infected with SARS-CoV, human coronavirus 229E, and influenza A (H1N1) virus were compared by using microarrays and real-time quantitative reverse transcriptase PCR. Secreted cytokines were measured with an enzyme-linked immunosorbent assay. SARS-CoV initiated viral gene transcription and protein synthesis in macrophages, but replication was abortive and no infectious virus was produced. In contrast to the case with human coronavirus 229E and influenza A virus, there was little or no induction of beta interferon (IFN-beta) in SARS-CoV-infected macrophages. Furthermore, SARS-CoV induced the expression of chemokines such as CXCL10/IFN-gamma-inducible protein 10 and CCL2/monocyte chemotactic protein 1. The poor induction of IFN-beta, a key component of innate immunity, and the ability of the virus to induce chemokines could explain aspects of the pathogenesis of SARS.


Assuntos
Citocinas/genética , Citocinas/metabolismo , Macrófagos/imunologia , Macrófagos/virologia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Animais , Células Cultivadas , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Quimiocina CXCL10 , Quimiocinas CXC/genética , Quimiocinas CXC/metabolismo , Perfilação da Expressão Gênica , Humanos , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/virologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral
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