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1.
J Immunol ; 202(11): 3267-3281, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31019060

RESUMO

Matrix metalloproteinase (MMP)-8 and -9 released by degranulating polymorphonuclear cells (PMNs) promote pericellular proteolysis by binding to PMN surfaces in a catalytically active tissue inhibitor of metalloproteinases (TIMP)-resistant forms. The PMN receptor(s) to which MMP-8 and MMP-9 bind(s) is not known. Competitive binding experiments showed that Mmp-8 and Mmp-9 share binding sites on murine PMN surfaces. A novel form of TIMP-1 (an inhibitor of soluble MMPs) is rapidly expressed on PMN surfaces when human PMNs are activated. Membrane-bound TIMP-1 is the PMN receptor for pro- and active MMP-8 and -9 as shown by the following: 1) TIMP-1 is strikingly colocalized with MMP-8 and -9 on activated human PMN surfaces and in PMN extracellular traps; 2) minimal immunoreactive and active Mmp-8 or Mmp-9 are detected on the surface of activated Timp-1-/- murine PMNs; and 3) binding of exogenous Timp-1 (but not Timp-2) to Timp-1-/- murine PMNs reconstitutes the binding of exogenous pro-Mmp-8 and pro-Mmp-9 to the surface of Timp-1-/- PMNs. Unlike full-length pro-Mmp-8 and pro-Mmp-9, mutant pro-Mmp proteins lacking the COOH-terminal hemopexin domain fail to bind to Mmp-8-/-x Mmp-9-/- murine PMNs. Soluble hemopexin inhibits the binding of pro-Mmp-8 and pro-Mmp-9 to Mmp-8-/-x Mmp-9-/- murine PMNs. Thus, the COOH-terminal hemopexin domains of pro-Mmp-8 and pro-Mmp-9 are required for their binding to membrane-bound Timp-1 on murine PMNs. Exposing nonhuman primates to cigarette smoke upregulates colocalized expression of TIMP-1 with MMP-8 and MMP-9 on peripheral blood PMN surfaces. By anchoring MMP-8 and MMP-9 to PMN surfaces, membrane-bound TIMP-1 plays a counterintuitive role in promoting PMN pericellular proteolysis occurring in chronic obstructive pulmonary disease and other diseases.

2.
Nat Genet ; 51(3): 494-505, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30804561

RESUMO

Chronic obstructive pulmonary disease (COPD) is the leading cause of respiratory mortality worldwide. Genetic risk loci provide new insights into disease pathogenesis. We performed a genome-wide association study in 35,735 cases and 222,076 controls from the UK Biobank and additional studies from the International COPD Genetics Consortium. We identified 82 loci associated with P < 5 × 10-8; 47 of these were previously described in association with either COPD or population-based measures of lung function. Of the remaining 35 new loci, 13 were associated with lung function in 79,055 individuals from the SpiroMeta consortium. Using gene expression and regulation data, we identified functional enrichment of COPD risk loci in lung tissue, smooth muscle, and several lung cell types. We found 14 COPD loci shared with either asthma or pulmonary fibrosis. COPD genetic risk loci clustered into groups based on associations with quantitative imaging features and comorbidities. Our analyses provide further support for the genetic susceptibility and heterogeneity of COPD.


Assuntos
Predisposição Genética para Doença/genética , Doença Pulmonar Obstrutiva Crônica/genética , Adulto , Idoso , Asma/genética , Estudos de Casos e Controles , Feminino , Expressão Gênica/genética , Loci Gênicos/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Fibrose Pulmonar/genética , Fumar/genética
3.
BMC Genomics ; 20(1): 22, 2019 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-30626320

RESUMO

BACKGROUND: Aging is affected by genetic and environmental factors, and cigarette smoking is strongly associated with accumulation of senescent cells. In this study, we wanted to identify genes that may potentially be beneficial for cell survival in response to cigarette smoke and thereby may contribute to development of cellular senescence. RESULTS: Primary human bronchial epithelial cells from five healthy donors were cultured, treated with or without 1.5% cigarette smoke extract (CSE) for 24 h or were passaged into replicative senescence. Transcriptome changes were monitored using RNA-seq in CSE and non-CSE exposed cells and those passaged into replicative senescence. We found that, among 1534 genes differentially regulated during senescence and 599 after CSE exposure, 243 were altered in both conditions, representing strong enrichment. Pathways and gene sets overrepresented in both conditions belonged to cellular processes that regulate reactive oxygen species, proteasome degradation, and NF-κB signaling. CONCLUSIONS: Our results offer insights into gene expression responses during cellular aging and cigarette smoke exposure, and identify potential molecular pathways that are altered by cigarette smoke and may also promote airway epithelial cell senescence.


Assuntos
Brônquios/metabolismo , Senescência Celular/genética , Fumar Cigarros/genética , Brônquios/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fumar Cigarros/efeitos adversos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , NF-kappa B/genética , Cultura Primária de Células , Espécies Reativas de Oxigênio/metabolismo , Análise de Sequência de RNA , Transdução de Sinais/efeitos dos fármacos
4.
Clin Respir J ; 12(11): 2598-2605, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30257066

RESUMO

BACKGROUND: Current risk factors for Chronic Obstructive Pulmonary Disease mortality focus only on overall and respiratory death. We investigated whether risk factors for each specific cause of mortality are different depending on the outcome under consideration. METHODS: This retrospective cohort study included patients with a clinical diagnosis of COPD, older than 40, greater than 20 pack-years smoking history, and obstructive pattern on spirometry. Collected data included baseline spirometry, comorbidities, medication use, tobacco exposure, severe exacerbations, and cause-specific mortality. RESULTS: This 512 patient cohort of heavy smokers included 277 (54.1%) males, was on average 66.4 ± 9.4 years of age and primarily non-Hispanic white, 395 (83.2%). The average FEV1% was 52.1% (SD = 16.9%) and the median COTE score was 2 (IQR: 0-6). A total of 67 deaths were of respiratory causes in 26 patients (38.8%), malignancies in 21 (31.1%), cardiovascular causes in 6 (9%), and from other etiologies in 14 patients (20.1%). COTE index,low predicted FEV1%, and lower body mass index were significant predictors of overall mortality. Predictors of respiratory deaths were significantly impacted by lower FEV1%, history of COPD exacerbations, lower BMI, and higher number of pack-years smoked. Risk factors for all other cause-specific mortality combined included history of malignancy or cardiovascular disease and smoking status. CONCLUSION: Cause-specific mortality risk factors differ in patients with COPD.

5.
Mol Cell Oncol ; 5(4): e1435182, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30250907

RESUMO

Hyperplastic airway epithelial cells may be the cause for increased risk for lung cancer in patients with chronic lung diseases. The B-cell lymphoma 2 (Bcl-2) family member, Bcl-2-interacting killer (BIK), triggers cell death specifically in these hyperplastic cells because of adequate presence of Death-associated Protein Kinase 1 (DAPk1), BCL-2 Antagonist Killer (BAK), and Extracellular Signal-regulated Kinase 1/2 (ERK1/2). Therefore, BIK may be a useful tool to control the development of lung cancer in patients with chronic diseases.

7.
Am J Respir Crit Care Med ; 198(10): 1254-1267, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-29750543

RESUMO

RATIONALE: ADAM8 (a disintegrin and metalloproteinase domain-8) is expressed by leukocytes and epithelial cells in health, but its contribution to the pathogenesis of chronic obstructive pulmonary disease (COPD) is unknown. OBJECTIVES: To determine whether the expression of ADAM8 is increased in the lungs of patients with COPD and cigarette smoke (CS)-exposed mice, and whether ADAM8 promotes the development of COPD. METHODS: ADAM8 levels were measured in lung, sputum, plasma, and/or BAL fluid samples from patients with COPD, smokers, and nonsmokers, and wild-type (WT) mice exposed to CS versus air. COPD-like lung pathologies were compared in CS-exposed WT versus Adam8-/- mice. MEASUREMENTS AND MAIN RESULTS: ADAM8 immunostaining was reduced in macrophages, and alveolar and bronchial epithelial cells in the lungs of patients with COPD versus control subjects, and CS- versus air-exposed WT mice. ADAM8 levels were similar in plasma, sputum, and BAL fluid samples from patients with COPD and control subjects. CS-exposed Adam8-/- mice had greater airspace enlargement and airway mucus cell metaplasia than WT mice, but similar small airway fibrosis. CS-exposed Adam8-/- mice had higher lung macrophage counts, oxidative stress levels, and alveolar septal cell death rates, but lower alveolar septal cell proliferation rates and soluble epidermal growth factor receptor BAL fluid levels than WT mice. Adam8 deficiency increased lung inflammation by reducing CS-induced activation of the intrinsic apoptosis pathway in macrophages. Human ADAM8 proteolytically shed the epidermal growth factor receptor from bronchial epithelial cells to reduce mucin expression in vitro. Adam8 bone marrow chimera studies revealed that Adam8 deficiency in leukocytes and lung parenchymal cells contributed to the exaggerated COPD-like disease in Adam8-/- mice. CONCLUSIONS: Adam8 deficiency increases CS-induced lung inflammation, emphysema, and airway mucus cell metaplasia. Strategies that increase or prolong ADAM8's expression in the lung may have therapeutic efficacy in COPD.

8.
COPD ; 15(2): 206-213, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29697285

RESUMO

The binary approach to the diagnosis of Chronic Bronchitis (CB) is a major barrier to the study of the disease. We investigated whether severity of productive cough can be graded using symptoms and presence of fixed airflow obstruction (FAO), and whether the severity correlates with health status, exposures injurious to the lung, biomarkers of inflammation, and measures of airway wall thickening. Findings from a cross-sectional sample of 1,422 participants from the Lovelace Smokers Cohort (LSC) were validated in 4,488 participants from the COPDGene cohort (COPDGene). Health status was based on the St. George's Respiratory Questionnaire, and Medical Outcomes Study 36-Item Short Form Health Survey. Circulating CC16 levels were quantified by ELISA (LSC), and airway wall thickening was measured using computed tomography (COPDGene). FAO was defined as postbronchodilator FEV1/FVC <0.7. The presence and duration of productive cough and presence of FAO or wheeze were graded into Healthy Smokers, Productive Cough (PC), Chronic PC, PC with Signs of Airflow Obstruction, and Chronic PC with Signs of Airflow Obstruction. In both cohorts, higher grade of severity correlated with lower health status, greater frequency of injurious exposures, greater airway wall thickening, and lower circulating CC16 levels. Further, longitudinal follow-up suggested that disease resolution can occur at every grade of severity but is more common in groups of lower severity and least common once airway remodeling develops. Therefore, severity of productive cough can be graded based on symptoms and FAO and early intervention may benefit patients by changing the natural history of disease.

9.
Am J Respir Cell Mol Biol ; 59(1): 13-17, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29522352

RESUMO

Chronic obstructive pulmonary disease (COPD) is a syndrome that comprises several lung pathologies, but subphenotyping the various disease subtypes has been difficult. One reason may be that current efforts focused on studying COPD once it has occurred do not allow tracing back to the different origins of disease. This perspective proposes that emphysema originates when susceptible airway, endothelial, and/or hematopoietic cells are exposed to environmental toxins such as cigarette smoke, biomass fuel, or traffic emissions. These susceptible cell types may initiate distinct pathobiological mechanisms ("COPD endotypes") that ultimately manifest the emphysematous destruction of the lung. On the basis of evidence from the "airway" endotype, we suggest that grading these endotypes by severity may allow better diagnosis of disease at early stages when intervention can be designed on the basis of the mechanisms involved. Therefore, genomic, proteomic, and metabolomic studies on at-risk patients will be important in the identification of biomarkers that help designate each endotype. Together with understanding of the involved molecular pathways that lead to disease manifestation, these efforts may lead to development of intervention strategies.

10.
Sci Rep ; 8(1): 436, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323189

RESUMO

Exposure to lipopolysaccharides (LPS) causes extensive neutrophilic inflammation in the airways followed by mucous cell hyperplasia (MCH) that is sustained by the anti-apoptotic protein, Bcl-2. To identify inflammatory factor(s) that are responsible for Bcl-2 expression, we established an organ culture system consisting of airway epithelial tissue from the rat nasal midseptum. The highest Muc5AC and Bcl-2 expression was observed when organ cultures were treated with brochoalveolar lavage (BAL) fluid harvested from rats 10 h post LPS instillation. Further, because BAL harvested from rats depleted of polymorphonuclear cells compared to controls showed increased Bcl-2 expression, analyses of cytokine levels in lavages identified IL-13 as an inducer of Bcl-2 expression. Ectopic IL-13 treatment of differentiated airway epithelial cells increased Bcl-2 and MUC5AC expression in the basal and apical regions of the cells, respectively. When Bcl-2 was blocked using shRNA or a small molecule inhibitor, ABT-263, mucous cell numbers were reduced due to increased apoptosis that disrupted the interaction of Bcl-2 with the pro-apoptotic protein, Bik. Furthermore, intranasal instillation of ABT-263 reduced the LPS-induced MCH in bik +/+ but not bik -/- mice, suggesting that Bik mediated apoptosis in hyperplastic mucous cells. Therefore, blocking Bcl-2 function could be useful in reducing IL-13 induced mucous hypersecretion.


Assuntos
Inflamação/metabolismo , Interleucina-13/metabolismo , Lipopolissacarídeos/efeitos adversos , Septo Nasal/citologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose , Líquido da Lavagem Broncoalveolar/imunologia , Hiperplasia , Masculino , Mucina-5AC/metabolismo , Septo Nasal/metabolismo , Septo Nasal/patologia , Técnicas de Cultura de Órgãos , Ratos
11.
Eur Respir J ; 51(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29301918

RESUMO

Exposure to household air pollution (HAP) from solid fuel combustion affects almost half of the world population. Adverse respiratory outcomes such as respiratory infections, impaired lung growth and chronic obstructive pulmonary disease have been linked to HAP exposure. Solid fuel smoke is a heterogeneous mixture of various gases and particulates. Cell culture and animal studies with controlled exposure conditions and genetic homogeneity provide important insights into HAP mechanisms. Impaired bacterial phagocytosis in exposed human alveolar macrophages possibly mediates several HAP-related health effects. Lung pathological findings in HAP-exposed individuals demonstrate greater small airways fibrosis and less emphysema compared with cigarette smokers. Field studies using questionnaires, air pollution monitoring and/or biomarkers are needed to better establish human risks. Some, but not all, studies suggest that improving cookstove efficiency or venting emissions may be associated with reduced respiratory symptoms, lung function decline in women and severe pneumonia in children. Current studies focus on fuel switching, stove technology replacements or upgrades and air filter devices. Several governments have initiated major programmes to accelerate the upgrade from solid fuels to clean fuels, particularly liquid petroleum gas, which provides research opportunities for the respiratory health community.

12.
Am J Respir Cell Mol Biol ; 58(6): 717-726, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29314865

RESUMO

Respiratory syncytial virus (RSV) is associated with enhanced progression of chronic obstructive pulmonary disease (COPD) and COPD exacerbations. However, little is known about the role of IL-17 in RSV-induced lung injury. We first investigated the role of RSV infection in enhancing mucous cell hyperplasia (MCH) and airspace enlargement in the lungs of mice injured with elastase and LPS (E/LPS). Mice injured with E/LPS had an enhanced and prolonged neutrophilic response to RSV that was associated with decreased levels of type I IFN and increased levels of IL-17, IL-23, CXCL-1, granulocyte colony stimulating factor (GCSF), CXCL-5, and matrix metalloproteinase (MMP)-9. In addition, extent of MCH and mean weighted alveolar space were increased significantly in the lungs of E/LPS-injured mice infected with RSV compared with E/LPS-only or RSV-only controls. Interestingly, immunodepletion of IL-17 before viral infection diminished the RSV-driven MCH and airspace enlargement in the E/LPS-injured animals, suggesting that IL-17 may be a therapeutic target for MCH and airspace enlargement when enhanced by RSV infection.

14.
Int J Chron Obstruct Pulmon Dis ; 12: 3171-3181, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29133979

RESUMO

Background: COPD is the third leading cause of death in the United States. Cigarette smoking accelerates the age-related forced expiratory volume in 1 s (FEV1) decline, an important determinant for the genesis of COPD. Hispanic smokers have lower COPD prevalence and FEV1 decline than non-Hispanic whites (NHWs). Patients and methods: A nutritional epidemiological study was conducted in the Lovelace Smokers cohort (LSC; n=1,829) and the Veterans Smokers cohort (n=508) to identify dietary nutrients (n=139) associated with average FEV1 and its decline and to assess whether nutrient intakes could explain ethnic disparity in FEV1 decline between Hispanics and NHW smokers. Results: Nutrients discovered and replicated to be significantly associated with better average FEV1 included magnesium, folate, niacin, vitamins A and D, eicosenoic fatty acid (20:1n9), eicosapentaenoic acid (20:5n3), docosapentaenoic acid (DPA; 22:5n3), docosahexaenoic acid (22:6n3), and fiber. In addition, greater intakes of eicosenoic fatty acid and DPA were associated with slower FEV1 decline in the LSC. Among omega 3 polyunsaturated fatty acids, DPA is the most potent nutrient associated with better average FEV1 and slower FEV1 decline. Adverse effect of continuous current smoking on FEV1 decline was completely negated in LSC members with high DPA intake (>20 mg/day). Slower FEV1 decline in Hispanics compared to NHWs may be due to the greater protection of eicosenoic fatty acid and DPA for FEV1 decline rather than greater intake of protective nutrients in this ethnic group. Conclusion: The protective nutrients for the preservation of FEV1 in ever smokers could lay foundation for designing individualized nutritional intervention targeting "optimal physiological levels" in human to improve lung function in ever smokers. Ethnic disparity in FEV1 decline may be explained by difference in magnitude of protection of dietary intakes of eicosenoic fatty acid and DPA between Hispanics and NHWs.


Assuntos
Fumar Cigarros/fisiopatologia , Dieta/etnologia , Ácido Eicosapentaenoico/administração & dosagem , Grupo com Ancestrais do Continente Europeu , Ácidos Graxos Insaturados/administração & dosagem , Hispano-Americanos , Pulmão/fisiopatologia , Estado Nutricional/etnologia , Fumantes , Adulto , Idoso , Fumar Cigarros/efeitos adversos , Fumar Cigarros/etnologia , Progressão da Doença , Feminino , Volume Expiratório Forçado , Disparidades nos Níveis de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , New Mexico/epidemiologia , Prevalência , Fatores de Proteção , Fatores de Risco
15.
Nat Commun ; 8(1): 803, 2017 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-28986568

RESUMO

Bik reduces hyperplastic epithelial cells by releasing calcium from endoplasmic reticulum stores and causing apoptosis, but the detailed mechanisms are not known. Here we report that Bik dissociates the Bak/Bcl-2 complex to enrich for ER-associated Bak and interacts with the kinase domain of DAPk1 to form Bik-DAPk1-ERK1/2-Bak complex. Bik also disrupts the Bcl2-IP3R interaction to cause ER Ca2+ release. The ER-associated Bak interacts with the kinase and calmodulin domains of DAPk1 to increase the contact sites of ER and mitochondria, and facilitate ER Ca2+ uptake by mitochondria. Although the Bik BH3 helix was sufficient to enrich for ER-Bak and elicit ER Ca2+ release, Bik-induced mitochondrial Ca2+ uptake is blocked with reduced Bak levels. Further, the Bik-derived peptide reduces allergen- and cigarette smoke-induced mucous cell hyperplasia in mice and in differentiated primary human airway epithelial cultures. Therefore, Bik peptides may have therapeutic potential in airway diseases associated with chronic mucous hypersecretion.Bcl-2 interacting killer (Bik) decreases airway epithelial hyperplasia via apoptosis mediated by calcium release from the endoplasmic reticulum (ER), but the mechanism is unclear. Here the authors show that Bik promotes Bak enrichment at the ER to tether mitochondria for efficient calcium transfer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Cálcio/metabolismo , Proteínas Quinases Associadas com Morte Celular/metabolismo , Retículo Endoplasmático/metabolismo , Células Epiteliais/metabolismo , Hiperplasia/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteína Killer-Antagonista Homóloga a bcl-2/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Alérgenos/farmacologia , Animais , Apoptose , Proteínas Reguladoras de Apoptose/farmacologia , Células Cultivadas , Humanos , Camundongos , Camundongos Knockout , Proteínas Mitocondriais/metabolismo , Peptídeos/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Mucosa Respiratória/citologia , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Fumaça , Produtos do Tabaco
16.
Environ Toxicol Pharmacol ; 55: 186-195, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28892756

RESUMO

Understanding the effect of wildfire smoke exposure on human health represents a unique interdisciplinary challenge to the scientific community. Population health studies indicate that wildfire smoke is a risk to human health and increases the healthcare burden of smoke-impacted areas. However, wildfire smoke composition is complex and dynamic, making characterization and modeling difficult. Furthermore, current efforts to study the effect of wildfire smoke are limited by availability of air quality measures and inconsistent air quality reporting among researchers. To help address these issues, we conducted a substantive review of wildfire smoke effects on population health, wildfire smoke exposure in occupational health, and experimental wood smoke exposure. Our goal was to evaluate the current literature on wildfire smoke and highlight important gaps in research. In particular we emphasize long-term health effects of wildfire smoke, recovery following wildfire smoke exposure, and health consequences of exposure in children.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Saúde Pública , Fumaça/efeitos adversos , Incêndios Florestais , Adulto , Poluentes Atmosféricos/análise , Animais , Pesquisa Biomédica , Criança , Exposição Ambiental , Feminino , Humanos , Masculino , Fumaça/análise
18.
Thorax ; 72(11): 998-1006, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28637835

RESUMO

BACKGROUND: COPD is a heterogeneous disease, but there is little consensus on specific definitions for COPD subtypes. Unsupervised clustering offers the promise of 'unbiased' data-driven assessment of COPD heterogeneity. Multiple groups have identified COPD subtypes using cluster analysis, but there has been no systematic assessment of the reproducibility of these subtypes. OBJECTIVE: We performed clustering analyses across 10 cohorts in North America and Europe in order to assess the reproducibility of (1) correlation patterns of key COPD-related clinical characteristics and (2) clustering results. METHODS: We studied 17 146 individuals with COPD using identical methods and common COPD-related characteristics across cohorts (FEV1, FEV1/FVC, FVC, body mass index, Modified Medical Research Council score, asthma and cardiovascular comorbid disease). Correlation patterns between these clinical characteristics were assessed by principal components analysis (PCA). Cluster analysis was performed using k-medoids and hierarchical clustering, and concordance of clustering solutions was quantified with normalised mutual information (NMI), a metric that ranges from 0 to 1 with higher values indicating greater concordance. RESULTS: The reproducibility of COPD clustering subtypes across studies was modest (median NMI range 0.17-0.43). For methods that excluded individuals that did not clearly belong to any cluster, agreement was better but still suboptimal (median NMI range 0.32-0.60). Continuous representations of COPD clinical characteristics derived from PCA were much more consistent across studies. CONCLUSIONS: Identical clustering analyses across multiple COPD cohorts showed modest reproducibility. COPD heterogeneity is better characterised by continuous disease traits coexisting in varying degrees within the same individual, rather than by mutually exclusive COPD subtypes.


Assuntos
Análise por Conglomerados , Volume Expiratório Forçado , Doença Pulmonar Obstrutiva Crônica/classificação , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Índice de Massa Corporal , Europa (Continente)/epidemiologia , Humanos , Fenótipo , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Reprodutibilidade dos Testes , Estados Unidos/epidemiologia
19.
Inhal Toxicol ; 29(3): 106-112, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28413916

RESUMO

OBJECTIVE: House dust mite (HDM) exposure is used to model experimental asthma in mice. However, a direct comparison of inflammatory responses following continuous versus intermittent HDM exposure has not been reported. Therefore, we investigated whether the HDM dose at sensitization or challenge affects extent of inflammation in mice that were either continuously or intermittently sensitized with HDM. MATERIALS AND METHODS: C57BL/6 mice received either 10 continuous exposures with 10 µg HDM per exposure or two intermittent HDM exposures over a period of two weeks and were subsequently challenged by three instillations with HDM during the third week. For the intermittent model, mice were sensitized with 1 or 10 µg HDM and challenged on three consecutive days with 1 or 10 µg HDM. Inflammatory cells in the bronchoalveolar lavage fluid and epithelial cell hyperplasia and mucous cell metaplasia were quantified. RESULTS: Significantly higher levels of inflammation and mucous cell metaplasia were observed when mice were sensitized intermittently compared with continuously. Intermittent sensitization and challenge with 10 µg HDM caused maximum inflammation, mucous cell metaplasia, and epithelial cell hyperplasia. However, sensitization with 1 µg HDM only also showed increased inflammation when challenged with 10 µg HDM. DISCUSSION: These findings suggest major differences in adaptive immunity, depending on the sensitization protocol. CONCLUSIONS: Because of significant differences, the HDM sensitization protocol should be carefully considered when designing studies to investigate the underlying mechanisms of immunity in mouse models of asthma.


Assuntos
Alérgenos/administração & dosagem , Hipersensibilidade/imunologia , Inflamação/imunologia , Pyroglyphidae/imunologia , Imunidade Adaptativa , Alérgenos/imunologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Células Epiteliais/patologia , Hiperplasia/patologia , Hipersensibilidade/patologia , Inflamação/patologia , Pulmão/imunologia , Masculino , Camundongos Endogâmicos C57BL
20.
Nat Genet ; 49(3): 426-432, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28166215

RESUMO

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality worldwide. We performed a genetic association study in 15,256 cases and 47,936 controls, with replication of select top results (P < 5 × 10-6) in 9,498 cases and 9,748 controls. In the combined meta-analysis, we identified 22 loci associated at genome-wide significance, including 13 new associations with COPD. Nine of these 13 loci have been associated with lung function in general population samples, while 4 (EEFSEC, DSP, MTCL1, and SFTPD) are new. We noted two loci shared with pulmonary fibrosis (FAM13A and DSP) but that had opposite risk alleles for COPD. None of our loci overlapped with genome-wide associations for asthma, although one locus has been implicated in joint susceptibility to asthma and obesity. We also identified genetic correlation between COPD and asthma. Our findings highlight new loci associated with COPD, demonstrate the importance of specific loci associated with lung function to COPD, and identify potential regions of genetic overlap between COPD and other respiratory diseases.


Assuntos
Loci Gênicos/genética , Predisposição Genética para Doença/genética , Pulmão/fisiologia , Doença Pulmonar Obstrutiva Crônica/genética , Fibrose Pulmonar/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Asma/genética , Feminino , Estudo de Associação Genômica Ampla/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Fatores de Risco , Fumar/genética
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