American journal of respiratory and critical care medicine
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Am. J. Respir. Crit. Care Med. · Jan 2012
Randomized Controlled Trial Comparative StudyDiesel exhaust exposure and nasal response to attenuated influenza in normal and allergic volunteers.
Diesel exhaust enhances allergic inflammation, and pollutants are associated with heightened susceptibility to viral respiratory infections. The effects of combined diesel and virus exposure in humans are unknown. ⋯ Short-term exposure to diesel exhaust leads to increased eosinophil activation and increased virus quantity after virus inoculation in those with allergic rhinitis. This is consistent with previous literature suggesting a diesel "adjuvant" effect promoting allergic inflammation, and our data further suggest this change may be associated with reduced virus clearance.Clinical trial registered with www.clinicaltrials.gov (NCT00617110).
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Vitamin D deficiency and asthma are common conditions that share risk factors such as African American ethnicity, inner-city residence, and obesity. This review provides a critical examination of current experimental and epidemiologic evidence of a causal association between vitamin D status and asthma or asthma morbidity, including potential protective mechanisms such as antiviral effects and enhanced steroid responsiveness. Because most published epidemiologic studies of vitamin D and asthma or asthma morbidity are observational, a recommendation for or against vitamin D supplementation as preventive or secondary treatment for asthma is not advisable and must await results of ongoing clinical trials. Should these trials confirm a beneficial effect of vitamin D, others will be needed to assess the role of vitamin D supplementation to prevent or treat asthma in different groups such as infants, children of school age, and ethnic minorities.
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Am. J. Respir. Crit. Care Med. · Jan 2012
ReviewSystemic steroids in severe sepsis and septic shock.
Despite more than 5 decades of study and debate, the role of corticosteroid treatment in patients with severe sepsis and septic shock remains controversial. Data support a beneficial effect on systemic blood pressure in patients with septic shock. ⋯ Unfortunately, the answer to these important questions is not readily evident based on the current evidence or the application of metaanalysis to the available clinical data. This concise evidence-based review highlights the strengths and weaknesses of the current data to inform the practicing clinician as to which patients are likely to derive significant benefit from corticosteroid treatment, while we await more definitive guidance from future multicenter, prospective, randomized, controlled trials designed to better answer these important therapeutic questions.
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Am. J. Respir. Crit. Care Med. · Jan 2012
Comparative StudyAlveolarization continues during childhood and adolescence: new evidence from helium-3 magnetic resonance.
The current hypothesis that human pulmonary alveolarization is complete by 3 years is contradicted by new evidence of alveolarization throughout adolescence in mammals. ⋯ Our observations are best explained by postulating that the lungs grow partly by neoalveolarization throughout childhood and adolescence. This has important implications: developing lungs have the potential to recover from early life insults and respond to emerging alveolar therapies. Conversely, drugs, diseases, or environmental exposures could adversely affect alveolarization throughout childhood.