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1.
J Infect Dis ; 219(11): 1786-1798, 2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-30566602

RESUMO

BACKGROUND: Adjuvant System 03 (AS03) markedly enhances responses to influenza A/H5N1 vaccines, but the mechanisms of this enhancement are incompletely understood. METHODS: Using ribonucleic acid sequencing on peripheral blood mononuclear cells (PBMCs) from AS03-adjuvanted and unadjuvanted inactivated H5N1 vaccine recipients, we identified differentially expressed genes, enriched pathways, and genes that correlated with serologic responses. We compared bulk PBMC findings with our previously published assessments of flow-sorted immune cell types. RESULTS: AS03-adjuvanted vaccine induced the strongest differential signals on day 1 postvaccination, activating multiple innate immune pathways including interferon and JAK-STAT signaling, Fcγ receptor (FcγR)-mediated phagocytosis, and antigen processing and presentation. Changes in signal transduction and immunoglobulin genes predicted peak hemagglutinin inhibition (HAI) titers. Compared with individual immune cell types, activated PBMC genes and pathways were most similar to innate immune cells. However, several pathways were unique to PBMCs, and several pathways identified in individual cell types were absent in PBMCs. CONCLUSIONS: Transcriptomic analysis of PBMCs after AS03-adjuvanted H5N1 vaccination revealed early activation of innate immune signaling, including a 5- to 8-fold upregulation of FcγR1A/1B/1C genes. Several early gene responses were correlated with HAI titer, indicating links with the adaptive immune response. Although PBMCs and cell-specific results shared key innate immune signals, unique signals were identified by both approaches.

3.
J Pediatric Infect Dis Soc ; 7(2): 165-168, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28369564

RESUMO

We detected human metapneumovirus (HMPV) in 54 (5%) of 1055 children aged 5 to 13 years with acute respiratory illness (ARI) identified by outpatient and emergency department surveillance between November and May 2003-2009. Its clinical features were similar to those of HMPV-negative ARI, except a diagnosis of pneumonia was more likely (13% vs 4%, respectively; P = .005) and a diagnosis of pharyngitis (7% vs 24%, respectively; P = .005) was less likely in patients with HMPV- positive ARI than those with HMPV-negative ARI.


Assuntos
Assistência Ambulatorial , Metapneumovirus , Infecções por Paramyxoviridae/epidemiologia , Infecções por Paramyxoviridae/virologia , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Adolescente , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Humanos , Masculino , Infecções por Paramyxoviridae/diagnóstico , Infecções Respiratórias/diagnóstico , Estados Unidos/epidemiologia
4.
Open Forum Infect Dis ; 4(3): ofx161, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28929126

RESUMO

BACKGROUND: Indoor smoke exposure is common in developing countries and may influence nasopharyngeal (NP) pneumococcal colonization density and risk of acute respiratory illness. We compared colonization density among Andean children living in households previously enrolled in a randomized controlled trial of a home intervention package including improved stoves to reduce smoke, kitchen sinks, and water disinfection. METHODS: We enrolled 260 children aged <3 years and made weekly household visits to assess for acute respiratory illness (ARI) and collect nasal swabs for respiratory virus polymerase chain reaction (PCR) testing during ARI. At monthly intervals, NP swabs were collected to determine pneumococcal colonization density through quantitative lytA PCR. We used linear quantile mixed-effects models to compare median log-transformed colonization densities among children in households randomized to the control (n = 129) versus intervention (n = 131) in sequential time points, accounting for random effects of multiple samples from individual children. Other covariates included age, sex, month, antibiotic exposure, and timing of sample collection relative to ARI with and without viral detection. RESULTS: Age and sociodemographic characteristics were similar between groups. Although no differences were observed in densities between groups, colonization density varied significantly over time in both groups, with highest densities coinciding with spring months. Time during and after virus-associated ARI was also associated with higher pneumococcal colonization density than time remote from ARIs. CONCLUSIONS: A home intervention package, including improved stoves, was not associated with changes in pneumococcal densities in young Andean children. However, increasing pneumococcal density was observed with spring season and viral-associated ARIs.

5.
J Clin Virol ; 96: 12-16, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28917132

RESUMO

BACKGROUND: Influenza C virus (ICV) is associated with acute respiratory illness. Yet ICV remains under recognized, with most previous studies using only culture to identify cases. OBJECTIVES: To develop a sensitive and specific real-time RT-PCR assay for ICV that allows for rapid and accurate detection in a clinical or research setting. STUDY DESIGN: Multiple ICV sequences obtained from GenBank were analyzed, including 141 hemagglutinin-esterase (HE), 106 matrix (M), and 97 nucleoprotein (NP) sequences. Primers and probes were designed based on conserved regions. Multiple primer-probe sets were tested against multiple ICV strains. RESULTS: The ICV M and NP genes offered the most conserved sequence regions. Primers and probes based on newer sequence data offered enhanced detection of ICV, especially for low titer specimens. An NP-targeted assay yielded the best performance and was capable of detecting 10-100 RNA copies per reaction. The NP assay detected multiple clinical isolates of ICV collected in a field epidemiology study conducted in Peru. CONCLUSIONS: We report a new real-time RT-PCR assay for ICV with high sensitivity and specificity.


Assuntos
Influenza Humana/diagnóstico , Influenza Humana/virologia , Influenzavirus C/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Pré-Escolar , Feminino , Humanos , Lactente , Influenzavirus C/genética , Masculino , Peru , Sensibilidade e Especificidade
6.
Proteomics ; 17(12)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28508465

RESUMO

Adjuvants enhance immunity elicited by vaccines through mechanisms that are poorly understood. Using a systems biology approach, we investigated temporal protein expression changes in five primary human immune cell populations: neutrophils, monocytes, natural killer cells, T cells, and B cells after administration of either an Adjuvant System 03 adjuvanted or unadjuvanted split-virus H5N1 influenza vaccine. Monocytes demonstrated the strongest differential signal between vaccine groups. On day 3 post-vaccination, several antigen presentation-related pathways, including MHC class I-mediated antigen processing and presentation, were enriched in monocytes and neutrophils and expression of HLA class I proteins was increased in the Adjuvant System 03 group. We identified several protein families whose proteomic responses predicted seroprotective antibody responses (>1:40 hemagglutination inhibition titer), including inflammation and oxidative stress proteins at day 1 as well as immunoproteasome subunit (PSME1 and PSME2) and HLA class I proteins at day 3 in monocytes. While comparison between temporal proteomic and transcriptomic results showed little overlap overall, enrichment of the MHC class I antigen processing and presentation pathway in monocytes and neutrophils was confirmed by both approaches.


Assuntos
Apresentação do Antígeno , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/uso terapêutico , Proteoma/metabolismo , Adjuvantes Imunológicos , Linfócitos B/citologia , Linfócitos B/imunologia , Linfócitos B/metabolismo , Células Cultivadas , Humanos , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Células Matadoras Naturais/citologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Monócitos/citologia , Monócitos/imunologia , Monócitos/metabolismo , Neutrófilos/citologia , Neutrófilos/imunologia , Neutrófilos/metabolismo , Mapas de Interação de Proteínas , Proteômica , Linfócitos T/citologia , Linfócitos T/imunologia , Linfócitos T/metabolismo
7.
BMC Infect Dis ; 17(1): 92, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28114885

RESUMO

BACKGROUND: The burden, clinical features, and molecular epidemiology of norovirus infection in young children in southern Africa are not well defined. METHODS: Using data from a health facility-based surveillance study of children <5 years in Lusaka Province, Zambia presenting with diarrhea, we assessed the burden of norovirus infection. A convenience sample of 454 stool specimens was tested for norovirus using reverse-transcriptase polymerase chain reaction (RT-PCR). RT-PCR positive samples underwent additional nucleotide sequencing for genogroup and genotype identification. Clinical features and severity of diarrheal illnesses were compared between norovirus-positive and -negative subjects using Chi-squared and t-tests. RESULTS: Norovirus was detected in 52/454 (11.5%) specimens tested. Abdominal pain, fever, and vomiting were the most common presenting features in norovirus-associated illnesses. However, there were no significant differences in the clinical features of norovirus-positive compared to norovirus-negative illnesses. Of 43 isolates that were available for sequencing, 31 (72.1%) were genogroup II (GII) and 12 (27.9%) were genogroup I (GI). The distribution of genotypes was diverse. CONCLUSIONS: Noroviruses were detected in approximately 10% of young children with diarrhea in the Lusaka Province of Zambia, with GII representing the majority of infections. These findings support the role of norovirus in symptomatic diarrhea disease in Africa. Further studies are needed to confirm these observations and to evaluate prevention strategies.


Assuntos
Infecções por Caliciviridae/epidemiologia , Gastroenterite/epidemiologia , Dor Abdominal/etiologia , Infecções por Caliciviridae/complicações , Infecções por Caliciviridae/virologia , Pré-Escolar , Diarreia/etiologia , Fezes/virologia , Feminino , Febre/etiologia , Gastroenterite/complicações , Gastroenterite/virologia , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Epidemiologia Molecular , Norovirus/genética , Norovirus/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vômito/etiologia , Zâmbia/epidemiologia
8.
PLoS One ; 12(1): e0167488, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28099485

RESUMO

BACKGROUND: Vaccine development for influenza A/H5N1 is an important public health priority, but H5N1 vaccines are less immunogenic than seasonal influenza vaccines. Adjuvant System 03 (AS03) markedly enhances immune responses to H5N1 vaccine antigens, but the underlying molecular mechanisms are incompletely understood. OBJECTIVE AND METHODS: We compared the safety (primary endpoint), immunogenicity (secondary), gene expression (tertiary) and cytokine responses (exploratory) between AS03-adjuvanted and unadjuvanted inactivated split-virus H5N1 influenza vaccines. In a double-blinded clinical trial, we randomized twenty adults aged 18-49 to receive two doses of either AS03-adjuvanted (n = 10) or unadjuvanted (n = 10) H5N1 vaccine 28 days apart. We used a systems biology approach to characterize and correlate changes in serum cytokines, antibody titers, and gene expression levels in six immune cell types at 1, 3, 7, and 28 days after the first vaccination. RESULTS: Both vaccines were well-tolerated. Nine of 10 subjects in the adjuvanted group and 0/10 in the unadjuvanted group exhibited seroprotection (hemagglutination inhibition antibody titer > 1:40) at day 56. Within 24 hours of AS03-adjuvanted vaccination, increased serum levels of IL-6 and IP-10 were noted. Interferon signaling and antigen processing and presentation-related gene responses were induced in dendritic cells, monocytes, and neutrophils. Upregulation of MHC class II antigen presentation-related genes was seen in neutrophils. Three days after AS03-adjuvanted vaccine, upregulation of genes involved in cell cycle and division was detected in NK cells and correlated with serum levels of IP-10. Early upregulation of interferon signaling-related genes was also found to predict seroprotection 56 days after first vaccination. CONCLUSIONS: Using this cell-based systems approach, novel mechanisms of action for AS03-adjuvanted pandemic influenza vaccination were observed. TRIAL REGISTRATION: ClinicalTrials.gov NCT01573312.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Biologia de Sistemas/métodos , Adolescente , Adulto , Anticorpos Antivirais/sangue , Formação de Anticorpos/imunologia , Apresentação do Antígeno/genética , Apresentação do Antígeno/imunologia , Quimiocina CXCL10/sangue , Células Dendríticas/imunologia , Método Duplo-Cego , Feminino , Testes de Inibição da Hemaglutinação , Humanos , Influenza Humana/imunologia , Interleucina-6/sangue , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Monócitos/imunologia , Neutrófilos/imunologia , Vacinação , Adulto Jovem
9.
AIDS Behav ; 21(3): 822-832, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26961538

RESUMO

The role of health literacy on HIV outcomes has not been evaluated widely in Africa, in part because few appropriate literacy measures exist. We developed a 16-item scale, the HIV Literacy Test (HIV-LT) to assess literacy-related tasks needed to participate in HIV care. Items were scored as correct or incorrect; higher scores indicated higher literacy skill (range 0-100 %). We tested internal reliability (Kuder-Richardson coefficient) of the HIV-LT in a convenience sample of 319 Portuguese-speaking, HIV infected adults on antiretroviral treatment in Maputo, Mozambique. Construct validity was assessed by a hypothetical model developed a priori. The HIV-LT was reliable and valid to measure participants' literacy skills. The mean HIV-LT score was 42 %; literacy skills applicable to HIV care were challenging for many participants. The HIV-LT could be used to assess the relationship of literacy and HIV-related outcomes in diverse settings, and evaluate interventions to improve health communication for those in HIV care.


Assuntos
Infecções por HIV/diagnóstico , Comunicação em Saúde , Alfabetização em Saúde , Psicometria/métodos , Inquéritos e Questionários , Adulto , Terapia Antirretroviral de Alta Atividade , Feminino , Infecções por HIV/tratamento farmacológico , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Moçambique , Reprodutibilidade dos Testes
11.
Open Forum Infect Dis ; 3(1): ofw001, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26900577

RESUMO

Background. Human rhinoviruses (HRVs) are frequently detected in children with acute respiratory illnesses (ARIs) but also in asymptomatic children. We compared features of ARI with HRV species (A, B, C) and determined genotypes associated with repeated HRV detections within individuals. Methods. We used clinical data and respiratory samples obtained from children <3 years old during weekly active household-based surveillance. A random subset of samples in which HRV was detected from individuals during both ARI and an asymptomatic period within 120 days of the ARI were genotyped. Features of ARI were compared among HRV species. Concordance of genotype among repeated HRV detections within individuals was assessed. Results. Among 207 ARI samples sequenced, HRV-A, HRV-B, and HRV-C were detected in 104 (50%), 20 (10%), and 83 (40%), respectively. Presence of fever, decreased appetite, and malaise were significantly higher in children with HRV-B. When codetections with other viruses were excluded (n = 155), these trends persisted, but some did not reach statistical significance. When 58 paired sequential HRV detections during asymptomatic and ARI episodes were sequenced, only 9 (16%) were identical genotypes of HRV. Conclusions. Clinical features may differ among HRV species. Repeated HRV detections in young children frequently represented acquisition of new HRV strains.

12.
Pediatr Infect Dis J ; 35(4): 455-7, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26673980

RESUMO

Human infection with Colletotrichum species is typically limited to ophthalmologic manifestations. We present the first reported pediatric case of subcutaneous Colletotrichum truncatum infection. This case highlights the potential importance of C. truncatum as an agent of subcutaneous or disseminated disease in immunocompromised children.


Assuntos
Colletotrichum , Dermatomicoses/diagnóstico , Dermatomicoses/etiologia , Pele/microbiologia , Pele/patologia , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Biópsia , Pré-Escolar , Dermatomicoses/terapia , Humanos , Masculino , Neuroblastoma/complicações , Neuroblastoma/tratamento farmacológico , Resultado do Tratamento
13.
Pediatr Infect Dis J ; 34(10): 1074-80, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26121205

RESUMO

BACKGROUND: Viruses are commonly detected in children with acute respiratory illnesses (ARIs) and in asymptomatic children. Longitudinal studies of viral detections during asymptomatic periods surrounding ARI could facilitate interpretation of viral detections but are currently scant. METHODS: We used reverse transcription polymerase chain reaction to analyze respiratory samples from young Andean children for viruses during asymptomatic periods within 8-120 days of index ARI (cough or fever). We compared viral detections over time within children and explored reverse transcription polymerase chain reaction cycle thresholds (CTs) as surrogates for viral loads. RESULTS: At least 1 respiratory virus was detected in 367 (43%) of 859 samples collected during asymptomatic periods, with more frequent detections in periods with rhinorrhea (49%) than those without (34%, P < 0.001). Relative to index ARI with human rhinovirus (HRV), adenovirus (AdV), respiratory syncytial virus (RSV) and parainfluenza virus detected, the same viruses were also detected during 32, 22, 10 and 3% of asymptomatic periods, respectively. RSV was only detected 8-30 days after index RSV ARI, whereas HRV and AdV were detected throughout asymptomatic periods. Human metapneumovirus and influenza were rarely detected during asymptomatic periods (<3%). No significant differences were observed in the CT for HRV or AdV during asymptomatic periods relative to ARI. For RSV, CTs were significantly lower during ARI relative to the asymptomatic period (P = 0.03). CONCLUSIONS: These findings indicate that influenza, human metapneumovirus, parainfluenza virus and RSV detections in children with an ARI usually indicate a causal relationship. When HRV or AdV is detected during ARI, the causal relationship is less certain.


Assuntos
Infecções Respiratórias/diagnóstico , Infecções Respiratórias/virologia , Carga Viral/métodos , Vírus/genética , Criança , Humanos , Peru , Distribuição Aleatória , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Vírus/isolamento & purificação
14.
PLoS One ; 10(2): e0118528, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25706537

RESUMO

Systems biology is an approach to comprehensively study complex interactions within a biological system. Most published systems vaccinology studies have utilized whole blood or peripheral blood mononuclear cells (PBMC) to monitor the immune response after vaccination. Because human blood is comprised of multiple hematopoietic cell types, the potential for masking responses of under-represented cell populations is increased when analyzing whole blood or PBMC. To investigate the contribution of individual cell types to the immune response after vaccination, we established a rapid and efficient method to purify human T and B cells, natural killer (NK) cells, myeloid dendritic cells (mDC), monocytes, and neutrophils from fresh venous blood. Purified cells were fractionated and processed in a single day. RNA-Seq and quantitative shotgun proteomics were performed to determine expression profiles for each cell type prior to and after inactivated seasonal influenza vaccination. Our results show that transcriptomic and proteomic profiles generated from purified immune cells differ significantly from PBMC. Differential expression analysis for each immune cell type also shows unique transcriptomic and proteomic expression profiles as well as changing biological networks at early time points after vaccination. This cell type-specific information provides a more comprehensive approach to monitor vaccine responses.


Assuntos
Sangue/imunologia , Vacinas contra Influenza/imunologia , Biologia de Sistemas , Humanos , Vacinas contra Influenza/administração & dosagem , Proteoma , Estações do Ano , Transcriptoma
15.
AIDS ; 28(7): 1041-8, 2014 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-24463393

RESUMO

OBJECTIVES: Little is known about adult caregivers' ability to accurately dose pediatric antiretroviral medications. We aimed to characterize the frequency of dosing errors for liquid zidovudine using two dosing devices and to evaluate the association between HIV literacy and dosing errors in adults living with HIV infection. DESIGN: Cross-sectional study enrolling 316 adults receiving combination antiretroviral therapy (cART) for HIV infection in Maputo Province, Mozambique. METHODS: Participants were administered the HIV Literacy Test (HIV-LT) and asked to measure 2.5 ml of liquid zidovudine using both a cup and syringe. Dosing measurement errors for liquid zidovudine were defined as 'any error' (≥ 20% deviation from reference dose) and 'major error' (≥ 40% deviation from reference dose). RESULTS: Dosing errors were common using the cup (any error: 50%, major error: 28%) and syringe (any error: 48% of participants, major error: 28%). There were no significant differences in proportions of any dosing error (P=0.61) or major dosing errors (P=0.82) between dosing instruments. In multivariable models, associations (P ≤ 0.03) were found between higher HIV-LT score and dosing errors for both the cup [any error adjusted odds ratio, AOR: 0.91 (0.84-0.99), major error AOR: 0.84 (0.75-0.92)] and syringe [any error AOR: 0.82 (0.75-0.90), major error AOR: 0.88 (0.80-0.97)]. CONCLUSION: Liquid antiretroviral medications are critical for prevention and treatment of pediatric HIV infections, yet dosing errors were exceedingly common in this population and were significantly associated with lower HIV literacy levels. Targeted interventions are needed to improve HIV knowledge and skills for pediatric medication dosing, particularly for caregivers with limited literacy.


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , Alfabetização em Saúde , Zidovudina/administração & dosagem , Adolescente , Adulto , Cuidadores , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Moçambique , Adulto Jovem
16.
J Proteome Res ; 12(3): 1108-19, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-23402659

RESUMO

Liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) has revolutionized the proteomics analysis of complexes, cells, and tissues. In a typical proteomic analysis, the tandem mass spectra from a LC-MS/MS experiment are assigned to a peptide by a search engine that compares the experimental MS/MS peptide data to theoretical peptide sequences in a protein database. The peptide spectra matches are then used to infer a list of identified proteins in the original sample. However, the search engines often fail to distinguish between correct and incorrect peptides assignments. In this study, we designed and implemented a novel algorithm called De-Noise to reduce the number of incorrect peptide matches and maximize the number of correct peptides at a fixed false discovery rate using a minimal number of scoring outputs from the SEQUEST search engine. The novel algorithm uses a three-step process: data cleaning, data refining through a SVM-based decision function, and a final data refining step based on proteolytic peptide patterns. Using proteomics data generated on different types of mass spectrometers, we optimized the De-Noise algorithm on the basis of the resolution and mass accuracy of the mass spectrometer employed in the LC-MS/MS experiment. Our results demonstrate De-Noise improves peptide identification compared to other methods used to process the peptide sequence matches assigned by SEQUEST. Because De-Noise uses a limited number of scoring attributes, it can be easily implemented with other search engines.


Assuntos
Algoritmos , Proteômica , Cromatografia Líquida , Bases de Dados de Proteínas , Humanos , Espectrometria de Massas em Tandem
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