American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Apr 2017
MMP-1 Activation Contributes to Airway Smooth Muscle Growth and Asthma Severity.
Matrix metalloproteinase-1 (MMP-1) and mast cells are present in the airways of people with asthma. ⋯ MMP-1 is activated by mast cell tryptase resulting in a proproliferative extracellular matrix. In asthma, mast cells are associated with airway smooth muscle growth, MMP-1 levels are associated with bronchial hyperresponsiveness, and MMP-1 activation are associated with exacerbation severity. Our findings suggest that airway smooth muscle/mast cell interactions contribute to asthma severity by transiently increasing MMP activation, airway smooth muscle growth, and airway responsiveness.
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Am. J. Respir. Crit. Care Med. · Apr 2017
Randomized Controlled Trial Multicenter StudyFluctuation Analysis of Peak Expiratory Flow and its Association with Treatment Failure in Asthma.
Temporal fluctuations have been demonstrated in lung function and asthma control, but the effect of controller therapy on these fluctuations is unknown. ⋯ We conclude that increased temporal self-similarity (α) of more variable lung function (CVpef) is associated with treatment failure, but the pattern of change in self-similarity leading up to treatment failure is variable across individuals.
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Am. J. Respir. Crit. Care Med. · Apr 2017
Randomized Controlled Trial Multicenter StudyRandomized Trial of Pleural Fluid Drainage Frequency in Patients with Malignant Pleural Effusions-The ASAP Trial.
Patients with malignant pleural effusions have significant dyspnea and shortened life expectancy. Indwelling pleural catheters allow patients to drain pleural fluid at home and can lead to autopleurodesis. The optimal drainage frequency to achieve autopleurodesis and freedom from catheter has not been determined. ⋯ Among patients with malignant pleural effusion, daily drainage of pleural fluid via an indwelling pleural catheter led to a higher rate of autopleurodesis and faster time to liberty from catheter. Clinical trial registered with www.clinicaltrials.gov (NCT 00978939).
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Am. J. Respir. Crit. Care Med. · Apr 2017
SIgA Deficiency in Individual Small Airways is Associated with Persistent Inflammation and Remodeling.
Maintenance of a surface immune barrier is important for homeostasis in organs with mucosal surfaces that interface with the external environment; however, the role of the mucosal immune system in chronic lung diseases is incompletely understood. ⋯ Our findings support the concept that localized, acquired SIgA deficiency in individual small airways of patients with COPD allows colonizing bacteria to cross the epithelial barrier and drive persistent inflammation and airway wall remodeling, even after smoking cessation.
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Am. J. Respir. Crit. Care Med. · Apr 2017
Electronic-cigarette Use and Respiratory Symptoms in Adolescents.
Rates of adolescent electronic (e-) cigarette use are increasing, but there has been little study of the chronic effects of use. Components of e-cigarette aerosol have known pulmonary toxicity. ⋯ Adolescent e-cigarette users had increased rates of chronic bronchitic symptoms. Further investigation is needed to determine the long-term effects of e-cigarettes on respiratory health.