American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Oct 2014
Enhanced Upper-airway Muscle Responsiveness is a Distinct Feature of Overweight/Obese Individuals Without Sleep Apnea.
Body habitus is a major determinant of obstructive sleep apnea (OSA). However, many individuals do not have OSA despite being overweight/obese (body mass index > 25 kg/m(2)) for reasons that are not fully elucidated. ⋯ Overweight/obese individuals without apnea have a moderately compromised upper-airway structure that is mitigated by highly responsive upper-airway dilator muscles to avoid OSA. Elucidating the mechanisms underlying enhanced muscle responses in this population may provide clues for novel OSA interventions.
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Am. J. Respir. Crit. Care Med. · Oct 2014
Lipoxin Generation is Related to Soluble Epoxide Hydrolase Activity in Severe Asthma.
Severe asthma is characterized by airway inflammatory responses associated with aberrant metabolism of arachidonic acid. Lipoxins (LX) are arachidonate-derived pro-resolving mediators that are decreased in severe asthma, yet mechanisms for defective LX biosynthesis and a means to increase LXs in severe asthma remain to be established. ⋯ LX levels were decreased by oxidative stress and sEH activity. Inhibitors of sEH increased LXs that mediated antiphlogistic actions, suggesting a new therapeutic approach for severe asthma. Clinical trial registered with www.clinicaltrials.gov (NCT 00595114).
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Am. J. Respir. Crit. Care Med. · Oct 2014
Randomized Controlled TrialSmooth Muscle in the Maintenance of Increased Airway Resistance Elicited by Methacholine in Humans.
Airway narrowing is maintained for a prolonged period after acute bronchoconstriction in humans in the absence of deep inspirations (DIs). ⋯ The maintenance of airway narrowing despite MCh clearance in humans is attributed to an intrinsic ability of ASM to maintain shortening during a progressive decrease of contractile stimulation.
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Am. J. Respir. Crit. Care Med. · Oct 2014
Observational StudyAsymptomatic HIV-infected Individuals on Antiretroviral Therapy Exhibit Impaired Lung CD4(+) T Cell Responses to Mycobacteria.
HIV-infected persons on antiretroviral therapy (ART) remain at higher risk of pulmonary tuberculosis (TB) than HIV-uninfected individuals. This increased susceptibility may be caused by impairment of alveolar macrophage (AM) function and/or mycobacteria-specific alveolar CD4(+) T-cell responses observed in HIV-infected ART-naive adults. ⋯ AM and mycobacteria-specific alveolar CD4(+) T-cell responses in HIV-infected adults on ART for less than 4 years are impaired and may partly explain the high risk of TB in HIV-infected individuals on ART. Strategies to augment ART to improve lung immune cell function and reduce the high incidence of TB in HIV-infected adults who initiate ART should be investigated.