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1.
Am J Respir Crit Care Med ; 197(3): 313-324, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29064281

RESUMEN

RATIONALE: Quantification of type 2 inflammation provided a molecular basis for heterogeneity in asthma. Non-type 2 pathways that contribute to asthma pathogenesis are not well understood. OBJECTIVES: To identify dysregulated pathways beyond type 2 inflammation. METHODS: We applied RNA sequencing to airway epithelial brushings obtained from subjects with stable mild asthma not on corticosteroids (n = 19) and healthy control subjects (n = 16). Sequencing reads were mapped to human and viral genomes. In the same cohort, and in a separate group with severe asthma (n = 301), we profiled blood gene expression with microarrays. MEASUREMENTS AND MAIN RESULTS: In airway brushings from mild asthma on inhaled corticosteroids, RNA sequencing yielded 1,379 differentially expressed genes (false discovery rate < 0.01). Pathway analysis revealed increased expression of type 2 markers, IFN-stimulated genes (ISGs), and endoplasmic reticulum (ER) stress-related genes. Airway epithelial ISG expression was not associated with type 2 inflammation in asthma or with viral transcripts but was associated with reduced lung function by FEV1 (ρ = -0.72; P = 0.0004). ER stress was confirmed by an increase in XBP1 (X-box binding protein 1) splicing in mild asthma and was associated with both type 2 inflammation and ISG expression. ISGs were also the most activated genes in blood cells in asthma and were correlated with airway ISG expression (ρ = 0.55; P = 0.030). High blood ISG expression in severe asthma was similarly unrelated to type 2 inflammation. CONCLUSIONS: ISG activation is prominent in asthma, independent of viral transcripts, orthogonal to type 2 inflammation, and associated with distinct clinical features. ER stress is associated with both type 2 inflammation and ISG expression.


Asunto(s)
Asma/genética , Asma/fisiopatología , Retículo Endoplásmico/genética , Regulación de la Expresión Génica , Factor 3 Regulador del Interferón/genética , Adulto , Estudios de Casos y Controles , Eosinófilos/inmunología , Femenino , Humanos , Mediadores de Inflamación/metabolismo , Masculino , Persona de Mediana Edad , Estrés Oxidativo/genética , ARN/genética , Valores de Referencia , Sensibilidad y Especificidad , Transducción de Señal
2.
Arch Virol ; 163(12): 3351-3356, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30159683

RESUMEN

Flanders virus (FLAV; family Rhabdoviridae) is a mosquito-borne hapavirus with no known pathology that is frequently isolated during arbovirus surveillance programs. Here, we document the presence of FLAV in Culex tarsalis mosquitoes and a Canada goose (Branta canadensis) collected in western North America, outside of the currently recognized range of FLAV. Until now, FLAV-like viruses detected in the western United States were assumed to be Hart Park virus (HPV, family Rhabdoviridae), a closely related congener. A re-examination of archived viral isolates revealed that FLAV was circulating in California as early as 1963. FLAV also was isolated in Nebraska, Colorado, South Dakota, North Dakota, and Saskatchewan, Canada. Phylogenetic analysis of the U1 pseudogene for 117 taxa and eight nuclear genes for 15 taxa demonstrated no distinct clustering between western FLAV isolates. Assuming the range of FLAV has been expanding west, these results indicate that FLAV likely spread west following multiple invasion events. However, it remains to be determined if the detection of FLAV in western North America is due to expansion or is a result of enhanced arbovirus surveillance or diagnostic techniques. Currently, the impact of FLAV infection remains unknown.


Asunto(s)
Enfermedades de las Aves/virología , Culex/virología , Gansos/virología , Mosquitos Vectores/virología , Infecciones por Rhabdoviridae/veterinaria , Rhabdoviridae/aislamiento & purificación , Animales , Enfermedades de las Aves/transmisión , América del Norte , Filogenia , Rhabdoviridae/clasificación , Rhabdoviridae/genética , Infecciones por Rhabdoviridae/transmisión , Infecciones por Rhabdoviridae/virología , Estaciones del Año
3.
J Gen Virol ; 98(10): 2425-2437, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28884664

RESUMEN

A few studies have highlighted the importance of the respiratory microbiome in modulating the frequency and outcome of viral respiratory infections. However, there are insufficient data on the use of microbial signatures as prognostic biomarkers to predict respiratory disease outcomes. In this study, we aimed to evaluate whether specific bacterial community compositions in the nasopharynx of children at the time of hospitalization are associated with different influenza clinical outcomes. We utilized retrospective nasopharyngeal (NP) samples (n=36) collected at the time of hospital arrival from children who were infected with influenza virus and had been symptomatic for less than 2 days. Based on their clinical course, children were classified into two groups: patients with mild influenza, and patients with severe respiratory or neurological complications. We implemented custom 16S rRNA gene sequencing, metagenomic sequencing and computational analysis workflows to classify the bacteria present in NP specimens at the species level. We found that increased bacterial diversity in the nasopharynx of children was strongly associated with influenza severity. In addition, patients with severe influenza had decreased relative abundance of Staphylococcus aureus and increased abundance of Prevotella (including P. melaninogenica), Streptobacillus, Porphyromonas, Granulicatella (including G. elegans), Veillonella (including V. dispar), Fusobacterium and Haemophilus in their nasopharynx. This pilot study provides proof-of-concept data for the use of microbial signatures as prognostic biomarkers of influenza outcomes. Further large prospective cohort studies are needed to refine and validate the performance of such microbial signatures in clinical settings.


Asunto(s)
Disbiosis , Gripe Humana/complicaciones , Gripe Humana/diagnóstico , Microbiota , Nasofaringe/microbiología , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Niño , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Humanos , Filogenia , Pronóstico , ARN Ribosómico 16S/genética , Estudios Retrospectivos , Análisis de Secuencia de ADN
4.
HIV Clin Trials ; 17(1): 29-37, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26899540

RESUMEN

OBJECTIVES: Antiretroviral regimen switching may be considered for HIV-1-infected, virologically-suppressed patients to enable treatment simplification or improve tolerability, but should be guided by knowledge of pre-existing drug resistance. The current study examined the impact of pre-existing drug resistance mutations on virologic outcomes among virologically-suppressed patients switching to Rilpivirine (RPV)/emtricitabine (FTC)/tenofovir disoproxil fumarate (TDF). METHODS: SPIRIT was a phase 3b study evaluating the safety and efficacy of switching to RPV/FTC/TDF in virologically-suppressed HIV-1-infected patients. Pre-existing drug resistance at baseline was determined by proviral DNA genotyping for 51 RPV/FTC/TDF-treated patients with known mutations by historical RNA genotype and matched controls and compared with clinical outcome at Week 48. RESULTS: Drug resistance mutations in protease or reverse transcriptase were detected in 62.7% of patients by historical RNA genotype and in 68.6% by proviral DNA genotyping at baseline. Proviral DNA sequencing detected 89% of occurrences of NRTI and NNRTI resistance-associated mutations reported by historical genotype. Mutations potentially affecting RPV activity, including E138A/G/K/Q, Y181C, and H221Y, were detected in isolates from 11 patients by one or both assays. None of the patients with single mutants had virologic failure through Week 48. One patient with pre-existing Y181Y/C and M184I by proviral DNA genotyping experienced virologic failure. Nineteen patients with K103N present by historical genotype were confirmed by proviral DNA sequencing and 18/19 remained virologically-suppressed. DISCUSSION: Virologic success rates were high among virologically-suppressed patients with pre-existing NRTI and NNRTI resistance-associated mutations who switched to RPV/FTC/TDF in the SPIRIT study. While plasma RNA genotyping remains preferred, proviral DNA genotyping may provide additional value in virologically-suppressed patients for whom historical resistance data are unavailable.


Asunto(s)
Farmacorresistencia Viral , Combinación Emtricitabina, Rilpivirina y Tenofovir/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Fármacos Anti-VIH/uso terapéutico , Genotipo , Humanos , Mutación , ARN Viral/genética , ARN Viral/metabolismo
5.
Arch Virol ; 160(1): 21-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25252815

RESUMEN

We describe the isolation of a novel flavivirus, isolated from a pool of mosquitoes identified as Culex (Culex) chidesteri collected in 2010 in the Pantanal region of west-central Brazil. The virus is herein designated Nhumirim virus (NHUV) after the name of the ranch from which the mosquito pool was collected. Flavivirus RNA was detected by real-time RT-PCR of homogenized mosquitoes and from the corresponding C6/36 culture supernatant. Based on full-genome sequencing, the virus isolate was genetically distinct from but most closely related to Barkedji virus (BJV), a newly described flavivirus from Senegal. Phylogenetic analysis demonstrated that NHUV grouped with mosquito-borne flaviviruses forming a clade with BJV. This clade may be genetically intermediate between the Culex-borne flaviviruses amplified by birds and the insect-only flaviviruses.


Asunto(s)
Culex/virología , Flavivirus/clasificación , Flavivirus/aislamiento & purificación , Animales , Brasil , Chlorocebus aethiops , Femenino , ARN Viral/clasificación , ARN Viral/genética , ARN Viral/aislamiento & purificación , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Garrapatas , Células Vero
6.
Proc Natl Acad Sci U S A ; 109(40): 16354-9, 2012 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-22988107

RESUMEN

Mucous cell hyperplasia and airway smooth muscle (ASM) hyperresponsiveness are hallmark features of inflammatory airway diseases, including asthma. Here, we show that the recently identified calcium-activated chloride channel (CaCC) TMEM16A is expressed in the adult airway surface epithelium and ASM. The epithelial expression is increased in asthmatics, particularly in secretory cells. Based on this and the proposed functions of CaCC, we hypothesized that TMEM16A inhibitors would negatively regulate both epithelial mucin secretion and ASM contraction. We used a high-throughput screen to identify small-molecule blockers of TMEM16A-CaCC channels. We show that inhibition of TMEM16A-CaCC significantly impairs mucus secretion in primary human airway surface epithelial cells. Furthermore, inhibition of TMEM16A-CaCC significantly reduces mouse and human ASM contraction in response to cholinergic agonists. TMEM16A-CaCC blockers, including those identified here, may positively impact multiple causes of asthma symptoms.


Asunto(s)
Canales de Cloruro/metabolismo , Mucinas/metabolismo , Contracción Muscular/fisiología , Músculo Liso/fisiología , Sistema Respiratorio/citología , Sistema Respiratorio/metabolismo , Animales , Anoctamina-1 , Células Cultivadas , Células Epiteliales/metabolismo , Humanos , Inmunohistoquímica , Ratones , Microscopía Fluorescente
7.
J Gen Virol ; 95(Pt 12): 2796-2808, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25146007

RESUMEN

In the past decade, there has been an upsurge in the number of newly described insect-specific flaviviruses isolated pan-globally. We recently described the isolation of a novel flavivirus (tentatively designated 'Nhumirim virus'; NHUV) that represents an example of a unique subset of apparently insect-specific viruses that phylogenetically affiliate with dual-host mosquito-borne flaviviruses despite appearing to be limited to replication in mosquito cells. We characterized the in vitro growth potential and 3' untranslated region (UTR) sequence homology with alternative flaviviruses, and evaluated the virus's capacity to suppress replication of representative Culex spp.-vectored pathogenic flaviviruses in mosquito cells. Only mosquito cell lines were found to support NHUV replication, further reinforcing the insect-specific phenotype of this virus. Analysis of the sequence and predicted RNA secondary structures of the 3' UTR indicated NHUV to be most similar to viruses within the yellow fever serogroup and Japanese encephalitis serogroup, and viruses in the tick-borne flavivirus clade. NHUV was found to share the fewest conserved sequence elements when compared with traditional insect-specific flaviviruses. This suggests that, despite apparently being insect specific, this virus probably diverged from an ancestral mosquito-borne flavivirus. Co-infection experiments indicated that prior or concurrent infection of mosquito cells with NHUV resulted in a significant reduction in virus production of West Nile virus (WNV), St Louis encephalitis virus (SLEV) and Japanese encephalitis virus. The inhibitory effect was most effective against WNV and SLEV with over a 10(6)-fold and 10(4)-fold reduction in peak titres, respectively.


Asunto(s)
Culicidae/citología , Flavivirus/genética , Flavivirus/aislamiento & purificación , Secuencia de Aminoácidos , Animales , Brasil , Línea Celular , Regulación Viral de la Expresión Génica , Datos de Secuencia Molecular , Filogenia , Proteínas Virales/genética , Proteínas Virales/metabolismo , Replicación Viral
8.
Eur Respir J ; 44(4): 985-93, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25142485

RESUMEN

Previously, we demonstrated concordance in differentially expressed genes in sarcoidosis blood and lung, implicating shared dysfunction of specific immune pathways. In the present study, we hypothesised that expression levels of candidate genes in sarcoidosis blood could predict and track with disease outcomes longitudinally. We applied Ingenuity Pathway Analysis to a cross-sectional derivation microarray dataset (n=38) to identify canonical pathways and candidate genes associated with sarcoidosis. In a separate longitudinal sarcoidosis cohort (n=103), we serially measured 48 candidate gene transcripts, and assessed their relation to disease chronicity and severity. In the cross-sectional derivation study, pathway analysis showed upregulation of genes related to interferon signalling and the role of pattern recognition receptors, and downregulation of T-cell receptor (TCR) signalling pathways in sarcoidosis. In the longitudinal cohort, factor analysis confirmed coregulation of genes marking these pathways and identified CXCL9 as an additional candidate pathway. CXCL9 and TCR factors discriminated between chronic versus nonprogressive disease, and CXCL9 predicted disease outcomes longitudinally. Interferon factor was similarly increased in both disease phenotypes. Factors associated with lung function decline included decreased TCR factor and increased CXCL9. These findings demonstrate blood transcriptomic signatures reflecting TCR signalling and CXCL9 predict sarcoidosis chronicity and correlate with disease severity longitudinally.


Asunto(s)
Sarcoidosis/sangre , Sarcoidosis/genética , Transcriptoma , Adulto , Anciano , Estudios Transversales , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad
9.
RNA Biol ; 10(4): 502-15, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23558773

RESUMEN

Use of second generation sequencing (SGS) technologies for transcriptional profiling (RNA-Seq) has revolutionized transcriptomics, enabling measurement of RNA abundances with unprecedented specificity and sensitivity and the discovery of novel RNA species. Preparation of RNA-Seq libraries requires conversion of the RNA starting material into cDNA flanked by platform-specific adaptor sequences. Each of the published methods and commercial kits currently available for RNA-Seq library preparation suffers from at least one major drawback, including long processing times, large starting material requirements, uneven coverage, loss of strand information and high cost. We report the development of a new RNA-Seq library preparation technique that produces representative, strand-specific RNA-Seq libraries from small amounts of starting material in a fast, simple and cost-effective manner. Additionally, we have developed a new quantitative PCR-based assay for precisely determining the number of PCR cycles to perform for optimal enrichment of the final library, a key step in all SGS library preparation workflows.


Asunto(s)
Escherichia coli/genética , Perfilación de la Expresión Génica/métodos , Biblioteca de Genes , Reacción en Cadena de la Polimerasa/métodos , Transcripción Reversa , Análisis de Secuencia de ARN/métodos , Secuencia de Bases , Línea Celular Tumoral , Biología Computacional , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos
10.
Am J Respir Crit Care Med ; 186(10): 965-74, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22955319

RESUMEN

RATIONALE: Changes in airway epithelial cell differentiation, driven in part by IL-13, are important in asthma. Micro-RNAs (miRNAs) regulate cell differentiation in many systems and could contribute to epithelial abnormalities in asthma. OBJECTIVES: To determine whether airway epithelial miRNA expression is altered in asthma and identify IL-13-regulated miRNAs. METHODS: We used miRNA microarrays to analyze bronchial epithelial brushings from 16 steroid-naive subjects with asthma before and after inhaled corticosteroids, 19 steroid-using subjects with asthma, and 12 healthy control subjects, and the effects of IL-13 and corticosteroids on cultured bronchial epithelial cells. We used quantitative polymerase chain reaction to confirm selected microarray results. MEASUREMENTS AND MAIN RESULTS: Most (12 of 16) steroid-naive subjects with asthma had a markedly abnormal pattern of bronchial epithelial miRNA expression by microarray analysis. Compared with control subjects, 217 miRNAs were differentially expressed in steroid-naive subjects with asthma and 200 in steroid-using subjects with asthma (false discovery rate < 0.05). Treatment with inhaled corticosteroids had modest effects on miRNA expression in steroid-naive asthma, inducing a statistically significant (false discovery rate < 0.05) change for only nine miRNAs. qPCR analysis confirmed differential expression of 22 miRNAs that were highly differentially expressed by microarrays. IL-13 stimulation recapitulated changes in many differentially expressed miRNAs, including four members of the miR-34/449 family, and these changes in miR-34/449 family members were resistant to corticosteroids. CONCLUSIONS: Dramatic alterations of airway epithelial cell miRNA levels are a common feature of asthma. These alterations are only modestly corrected by inhaled corticosteroids. IL-13 effects may account for some of these alterations, including repression of miR-34/449 family members that have established roles in airway epithelial cell differentiation. Clinical trial registered with www.clinicaltrials.gov (NCT 00595153).


Asunto(s)
Asma/metabolismo , Bronquios/metabolismo , Células Epiteliales/metabolismo , MicroARNs/metabolismo , Administración por Inhalación , Adulto , Asma/tratamiento farmacológico , Asma/genética , Bronquios/efectos de los fármacos , Budesonida/administración & dosificación , Células Cultivadas , Relación Dosis-Respuesta a Droga , Células Epiteliales/efectos de los fármacos , Femenino , Glucocorticoides/administración & dosificación , Humanos , Interleucina-13/farmacología , Masculino , MicroARNs/genética , MicroARNs/fisiología , Análisis por Micromatrices , Reacción en Cadena de la Polimerasa
11.
J Allergy Clin Immunol ; 130(3): 647-654.e10, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22857879

RESUMEN

BACKGROUND: Eosinophilic airway inflammation is heterogeneous in asthmatic patients. We recently described a distinct subtype of asthma defined by the expression of genes inducible by T(H)2 cytokines in bronchial epithelium. This gene signature, which includes periostin, is present in approximately half of asthmatic patients and correlates with eosinophilic airway inflammation. However, identification of this subtype depends on invasive airway sampling, and hence noninvasive biomarkers of this phenotype are desirable. OBJECTIVE: We sought to identify systemic biomarkers of eosinophilic airway inflammation in asthmatic patients. METHODS: We measured fraction of exhaled nitric oxide (Feno), peripheral blood eosinophil, periostin, YKL-40, and IgE levels and compared these biomarkers with airway eosinophilia in asthmatic patients. RESULTS: We collected sputum, performed bronchoscopy, and matched peripheral blood samples from 67 asthmatic patients who remained symptomatic despite maximal inhaled corticosteroid treatment (mean FEV(1), 60% of predicted value; mean Asthma Control Questionnaire [ACQ] score, 2.7). Serum periostin levels are significantly increased in asthmatic patients with evidence of eosinophilic airway inflammation relative to those with minimal eosinophilic airway inflammation. A logistic regression model, including sex, age, body mass index, IgE levels, blood eosinophil numbers, Feno levels, and serum periostin levels, in 59 patients with severe asthma showed that, of these indices, the serum periostin level was the single best predictor of airway eosinophilia (P = .007). CONCLUSION: Periostin is a systemic biomarker of airway eosinophilia in asthmatic patients and has potential utility in patient selection for emerging asthma therapeutics targeting T(H)2 inflammation.


Asunto(s)
Asma/sangre , Moléculas de Adhesión Celular/sangre , Eosinofilia/diagnóstico , Inflamación/diagnóstico , Adipoquinas/sangre , Adulto , Asma/tratamiento farmacológico , Biomarcadores , Pruebas Respiratorias , Proteína 1 Similar a Quitinasa-3 , Eosinofilia/sangre , Eosinófilos/fisiología , Femenino , Humanos , Inmunoglobulina E/sangre , Inflamación/sangre , Interleucina-13/análisis , Interleucina-13/fisiología , Lectinas/sangre , Modelos Logísticos , Masculino , Persona de Mediana Edad , Óxido Nítrico/análisis
12.
Am J Respir Crit Care Med ; 184(10): 1153-63, 2011 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-21852540

RESUMEN

RATIONALE: Sarcoidosis is a granulomatous disease of unknown etiology, although M. tuberculosis may play a role in the pathogenesis. The traditional view holds that inflammation in sarcoidosis is compartmentalized to involved organs. OBJECTIVES: To determine whether whole blood gene expression signatures reflect inflammatory pathways in the lung in sarcoidosis and whether these signatures overlap with tuberculosis. METHODS: We analyzed transcriptomic data from blood and lung biopsies in sarcoidosis and compared these profiles with blood transcriptomic data from tuberculosis and other diseases. MEASUREMENTS AND MAIN RESULTS: Applying machine learning algorithms to blood gene expression data, we built a classifier that distinguished sarcoidosis from health in derivation and validation cohorts (92% sensitivity, 92% specificity). The most discriminative genes were confirmed by quantitative PCR and correlated with disease severity. Transcript profiles significantly induced in blood overlapped with those in lung biopsies and identified shared dominant inflammatory pathways (e.g., Type-I/II interferons). Sarcoidosis and tuberculosis shared more overlap in blood gene expression compared with other diseases using the 86-gene signature reported to be specific for tuberculosis and the sarcoidosis signature presented herein, although reapplication of machine learning algorithms could identify genes specific for sarcoidosis. CONCLUSIONS: These data indicate that blood transcriptome analysis provides a noninvasive method for identifying inflammatory pathways in sarcoidosis, that these pathways may be leveraged to complement more invasive procedures for diagnosis or assessment of disease severity, and that sarcoidosis and tuberculosis share overlap in gene regulation of specific inflammatory pathways.


Asunto(s)
Inflamación/metabolismo , Pulmón/metabolismo , Sarcoidosis Pulmonar/metabolismo , Transcriptoma/genética , Tuberculosis Pulmonar/metabolismo , Algoritmos , Biopsia con Aguja , Estudios de Casos y Controles , Femenino , Perfilación de la Expresión Génica , Humanos , Inflamación/genética , Pulmón/inmunología , Pulmón/patología , Masculino , Persona de Mediana Edad , Curva ROC , Reacción en Cadena en Tiempo Real de la Polimerasa , Sarcoidosis Pulmonar/sangre , Sarcoidosis Pulmonar/genética , Sarcoidosis Pulmonar/patología , Índice de Severidad de la Enfermedad , Tuberculosis Pulmonar/sangre , Tuberculosis Pulmonar/genética
13.
J Allergy Clin Immunol ; 125(5): 1046-1053.e8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20451039

RESUMEN

BACKGROUND: Previously, we found that mast cell tryptases and carboxypeptidase A3 (CPA3) are differentially expressed in the airway epithelium in asthmatic subjects. We also found that asthmatic subjects can be divided into 2 subgroups ("T(H)2 high" and "T(H)2 low" asthma) based on epithelial cell gene signatures for the activity of T(H)2 cytokines. OBJECTIVES: We sought to characterize intraepithelial mast cells (IEMCs) in asthma. METHODS: We performed gene expression profiling in epithelial brushings and stereology-based quantification of mast cell numbers in endobronchial biopsy specimens from healthy control and asthmatic subjects before and after treatment with inhaled corticosteroids (ICSs). We also performed gene expression and protein quantification studies in cultured airway epithelial cells and mast cells. RESULTS: By means of unsupervised clustering, mast cell gene expression in the airway epithelium related closely to the expression of IL-13 signature genes. The levels of expression of mast cell genes correlate positively with lung function improvements with ICSs. IEMC density was 2-fold higher than normal in subjects with T(H)2-high asthma compared with that seen in subjects with T(H)2-low asthma or healthy control subjects (P = .015 for both comparisons), and these cells were characterized by expression of tryptases and CPA3 but not chymase. IL-13 induced expression of stem cell factor in cultured airway epithelial cells, and mast cells exposed to conditioned media from IL-13-activated epithelial cells showed downregulation of chymase but no change in tryptase or CPA3 expression. CONCLUSION: IEMC numbers are increased in subjects with T(H)2-high asthma, have an unusual protease phenotype (tryptase and CPA3 high and chymase low), and predict responsiveness to ICSs. IL-13-stimulated production of stem cell factor by epithelial cells potentially explains mast cell accumulation in T(H)2-high asthmatic epithelium.


Asunto(s)
Asma , Células Epiteliales/inmunología , Mastocitos/inmunología , Péptido Hidrolasas/clasificación , Péptido Hidrolasas/metabolismo , Células Th2/inmunología , Adulto , Asma/inmunología , Asma/fisiopatología , Carboxipeptidasas A/genética , Carboxipeptidasas A/metabolismo , Células Cultivadas , Quimasas/genética , Quimasas/metabolismo , Citocinas/genética , Citocinas/metabolismo , Citocinas/farmacología , Células Epiteliales/citología , Células Epiteliales/enzimología , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Interleucina-13/genética , Interleucina-13/metabolismo , Interleucina-13/farmacología , Masculino , Mastocitos/citología , Mastocitos/enzimología , Persona de Mediana Edad , Péptido Hidrolasas/genética , Fenotipo , Factor de Células Madre , Triptasas/genética , Triptasas/metabolismo , Adulto Joven
14.
Clin Infect Dis ; 49(3): 365-71, 2009 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-19538087

RESUMEN

BACKGROUND: Antimicrobial drugs used in human infection treatment and animal husbandry may select for drug-resistant bacterial pathogens, which are increasingly observed worldwide. We sought to examine the extent to which identical mobile drug resistance elements are shared across common pathogens isolated from human and animal sources. METHODS: We compared the distribution of one class of mobile elements--integrons and gene cassettes--among uropathogenic Escherichia coli isolates, Salmonella enterica serovar Typhimurium isolates from human diarrhea cases, and E. coli and Salmonella isolates from nonhuman sources in the United States. The sequences of the gene cassettes were also compared with those deposited in GenBank. RESULTS: Class 1 integrons were detected in 68 (49%) of 139 uropathogenic E. coli isolates, 16 (72%) of 22 human and animal Salmonella isolates, and 120 (28%) of 436 nonhuman E. coli isolates. The most prevalent cassettes were those encoding aminoglycoside adenyltransferase A (aadA) and dihydrofolate reductase A (dfrA). Sequences of aadA1, dfrA12-orfF-aadA2, and dfrA17-aadA5 gene cassettes from 35 urinary tract infection E. coli isolates and of aadA2 and aadA12 gene cassettes from 7 Salmonella isolates were 100% identical to the corresponding cassette sequences from food animal E. coli isolates and those deposited in GenBank from a wide variety of bacteria isolated from animal hosts from distinct regions of the world. CONCLUSION: Common community-acquired human drug-resistant infections are caused by bacterial strains that harbor mobile drug resistance determinants of identical sequences that are found in diverse bacterial species from varied animal sources worldwide.


Asunto(s)
Infecciones Comunitarias Adquiridas/microbiología , Farmacorresistencia Bacteriana , Infecciones por Escherichia coli/veterinaria , Escherichia coli/efectos de los fármacos , Salmonelosis Animal/microbiología , Infecciones por Salmonella/microbiología , Salmonella typhimurium/efectos de los fármacos , Animales , Antibacterianos/farmacología , Bovinos , Pollos , ADN Bacteriano/química , ADN Bacteriano/genética , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Femenino , Humanos , Secuencias Repetitivas Esparcidas , Datos de Secuencia Molecular , Salmonella typhimurium/genética , Salmonella typhimurium/aislamiento & purificación , Análisis de Secuencia de ADN , Porcinos , Pavos , Estados Unidos
15.
J Med Virol ; 81(12): 2109-13, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19856474

RESUMEN

Previous studies suggest that the emerging G9P[8] genotype was the most prevalent rotavirus genotype in Ecuador during 2005. This present study provides a temporal analysis of the distribution of rotavirus genotypes in two locations within Ecuador by adding additional years (2006 - early 2008) to the originally reported 2005 data. Data were collected in a rural (northern coastal Ecuador) and urban (Quito) area. In the rural area, a community sample of cases (those presenting diarrhea) and controls (those not presenting diarrhea) were collected between August 2003 and March 2008 resulting in a total of 3,300 stool samples (876 cases and 2,424 controls). Of these samples, 260 were positive for rotavirus by an immunochromatographic test (196 cases and 64 controls). In Quito, 59 fecal samples were collected from children presenting diarrhea and diagnosed with rotavirus. An RT-PCR analysis of samples collected between 2005 and 2007 suggested that G9 was replaced by G1 and G2 in the rural and urban settings. During this period G9 decreased from 79% to 9% while G2 increased from 0% to 43% in the rural communities, and G9 decreased from 79% to 37% while G2 increased from 3% to 57% in the urban area of Quito. This rapid replacement of G9 by G1 and G2 reinforces the necessity of surveillance to inform vaccination programs.


Asunto(s)
Variación Genética , Infecciones por Rotavirus , Rotavirus/genética , Adolescente , Adulto , Niño , Preescolar , Ecuador/epidemiología , Heces/virología , Genoma Viral , Hospitales Urbanos , Humanos , Lactante , Persona de Mediana Edad , ARN Viral/genética , ARN Viral/aislamiento & purificación , Infecciones por Rotavirus/epidemiología , Infecciones por Rotavirus/virología , Población Rural
16.
Hum Immunol ; 69(7): 443-64, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18638659

RESUMEN

This paper presents a meta-analysis of high-resolution human leukocyte antigen (HLA) allele frequency data describing 497 population samples. Most of the datasets were compiled from studies published in eight journals from 1990 to 2007; additional datasets came from the International Histocompatibility Workshops and from the AlleleFrequencies.net database. In all, these data represent approximately 66,800 individuals from throughout the world, providing an opportunity to observe trends that may not have been evident at the time the data were originally analyzed, especially with regard to the relative importance of balancing selection among the HLA loci. Population genetic measures of allele frequency distributions were summarized across populations by locus and geographic region. A role for balancing selection maintaining much of HLA variation was confirmed. Further, the breadth of this meta-analysis allowed the ranking of the HLA loci, with DQA1 and HLA-C showing the strongest balancing selection and DPB1 being compatible with neutrality. Comparisons of the allelic spectra reported by studies since 1990 indicate that most of the HLA alleles identified since 2000 are very-low-frequency alleles. The literature-based allele-count data, as well as maps summarizing the geographic distributions for each allele, are available online.


Asunto(s)
Alelos , Frecuencia de los Genes , Antígenos HLA/genética , África , Américas , Asia , Europa (Continente) , Genética de Población , Humanos , Desequilibrio de Ligamiento , Oceanía , Polimorfismo Genético
17.
Am J Trop Med Hyg ; 76(3): 528-33, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17360879

RESUMEN

Enteroinvasive Escherichia coli (EIEC) causes dysentery; however, it is less widely reported than other etiological agents in studies of diarrhea worldwide. Between August 2003 and July 2005, stool samples were collected in case-control studies in 22 rural communities in northwestern Ecuador. Infection was assessed by PCR specific for LT and STa genes of enterotoxigenic E. coli (ETEC), the bfp gene of enteropathogenic E. coli (EPEC), and the ipaH gene of both enteroinvasive E. coli and Shigellae. The pathogenic E. coli most frequently identified were EIEC (3.2 cases/100 persons) and Shigellae (1.5 cases/100 persons), followed by ETEC (1.3 cases/100 persons), and EPEC (0.9 case/100 persons). EIEC exhibited similar risk-factor relationships with other pathotypes analyzed but different age-specific infection rates. EIEC was the predominant diarrheagenic bacteria isolated in our community-based study, a unique observation compared with other regions of the world.


Asunto(s)
Diarrea/microbiología , Escherichia coli/aislamiento & purificación , Adolescente , Adulto , Distribución por Edad , Anciano , Estudios de Casos y Controles , Niño , Preescolar , Electroforesis en Gel de Campo Pulsado , Escherichia coli/clasificación , Humanos , Lactante , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Prevalencia , Factores de Riesgo
18.
J Med Microbiol ; 56(Pt 10): 1363-1369, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17893175

RESUMEN

The application of genotyping techniques for subtyping uropathogenic Escherichia coli has contributed to better understanding of the epidemiology of community-acquired urinary tract infection (UTI). However, the current techniques are hampered by limited reproducibility, poor discriminatory power, labour-intensive performance or high cost. A screening test that is sequence-based would provide an inexpensive, reproducible way to subtype E. coli isolates. Such a test, if also discriminatory, would be highly useful for epidemiological studies. The discriminatory ability of 12 putative virulence genes (fimH, fliD, fliM, iha, motA, papA/H, kpsMTII, fepE, fimA, flgA, malG, purD) was evaluated based on single nucleotide polymorphisms (SNPs) in nine uropathogenic E. coli isolates, all previously found to belong to a single multilocus sequence type (MLST) complex (ST69). An additional 25 epidemiologically well-characterized E. coli isolates belonging to 12 distinct MLST clonal complexes were analysed for fimH SNP. None of the 12 genes except fimH were able to further discriminate the nine ST69-complex strains. Isolates belonging to the 12 non-ST69 MLST groups were separated into 10 fimH SNP subgroups. While fimH SNP analysis may not be an appropriate phylogenetic method, it offers discriminatory power similar to that of MLST and could be used as a simple, inexpensive screening test for epidemiological studies of uropathogenic E. coli.


Asunto(s)
Adhesinas de Escherichia coli/genética , Técnicas de Tipificación Bacteriana/métodos , Escherichia coli/clasificación , Escherichia coli/genética , Proteínas Fimbrias/genética , Polimorfismo de Nucleótido Simple , Infecciones Urinarias/microbiología , Animales , Análisis por Conglomerados , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/microbiología , Humanos , Homología de Secuencia
19.
Genome Announc ; 4(6)2016 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-27811095

RESUMEN

Genomic sequences are described from five novel viruses and divergent strains of Brejeira and Guaico Culex viruses from mosquitoes collected in Pantanal, Brazil, in 2010.

20.
J Int Assoc Provid AIDS Care ; 14(5): 398-401, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26188010

RESUMEN

Transmitted HIV-1 exhibiting reduced susceptibility to protease and reverse transcriptase inhibitors is well documented but limited for integrase inhibitors and enfuvirtide. We describe here a case of transmitted 5 drug class-resistance in an antiretroviral (ARV)-naïve patient who was successfully treated based on the optimized selection of an active ARV drug regimen. The value of baseline resistance testing to determine an optimal ARV treatment regimen is highlighted in this case report.


Asunto(s)
Antirretrovirales/administración & dosificación , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Adulto , Ciclohexanos/administración & dosificación , Farmacorresistencia Viral , Enfuvirtida , Proteína gp41 de Envoltorio del VIH/administración & dosificación , Inhibidores de Integrasa VIH/administración & dosificación , VIH-1/fisiología , Humanos , Masculino , Maraviroc , Fragmentos de Péptidos/administración & dosificación , Triazoles/administración & dosificación , Tropismo Viral
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