American journal of respiratory and critical care medicine
-
Am. J. Respir. Crit. Care Med. · Sep 2011
Comparative StudyFas determines differential fates of resident and recruited macrophages during resolution of acute lung injury.
During acute lung injury (ALI) the macrophage pool expands markedly as inflammatory monocytes migrate from the circulation to the airspaces. As inflammation resolves, macrophage numbers return to preinjury levels and normal tissue structure and function are restored. ⋯ These findings indicate that Fas-induced apoptosis of recruited macrophages is essential for complete resolution of ALI.
-
Am. J. Respir. Crit. Care Med. · Sep 2011
Practice GuidelineAn official ATS clinical practice guideline: interpretation of exhaled nitric oxide levels (FENO) for clinical applications.
Measurement of fractional nitric oxide (NO) concentration in exhaled breath (Fe(NO)) is a quantitative, noninvasive, simple, and safe method of measuring airway inflammation that provides a complementary tool to other ways of assessing airways disease, including asthma. While Fe(NO) measurement has been standardized, there is currently no reference guideline for practicing health care providers to guide them in the appropriate use and interpretation of Fe(NO) in clinical practice. ⋯ In the setting of chronic inflammatory airway disease including asthma, conventional tests such as FEV(1) reversibility or provocation tests are only indirectly associated with airway inflammation. Fe(NO) offers added advantages for patient care including, but not limited to (1) detecting of eosinophilic airway inflammation, (2) determining the likelihood of corticosteroid responsiveness, (3) monitoring of airway inflammation to determine the potential need for corticosteroid, and (4) unmasking of otherwise unsuspected nonadherence to corticosteroid therapy.
-
Am. J. Respir. Crit. Care Med. · Sep 2011
Comparative StudyLy6Chi monocytes direct alternatively activated profibrotic macrophage regulation of lung fibrosis.
Idiopathic pulmonary fibrosis (IPF) is a devastating disease. Antiinflammatory therapies, including corticosteroids, are of no benefit. The role of monocytes and macrophages is therefore controversial. ⋯ We demonstrate the importance of circulating monocytes and lung macrophages during pulmonary fibrosis, and emphasize the importance of the alternatively activated macrophage phenotype. We show that Ly6Chi monocytes facilitate the progression of pulmonary fibrosis, but are not obviously engrafted into lungs thereafter. Finally, we provide empirical data to suggest that macrophages may have a resolution-promoting role during the reversible phase of bleomycin-induced pulmonary fibrosis.
-
Am. J. Respir. Crit. Care Med. · Sep 2011
Comparative StudyInhibiting lung elastase activity enables lung growth in mechanically ventilated newborn mice.
Mechanical ventilation with O₂-rich gas (MV-O₂) offers life-saving treatment for respiratory failure, but also promotes lung injury. We previously reported that MV-O2 of newborn mice increased lung elastase activity, causing elastin degradation and redistribution of elastic fibers from septal tips to alveolar walls. These changes were associated with transforming growth factor (TGF)-β activation and increased apoptosis leading to defective alveolarization and lung growth arrest, as seen in neonatal chronic lung disease. ⋯ Intratracheal elafin, by blocking lung protease activity, prevented MV-O₂-induced elastin degradation, TGF-β activation, apoptosis, and dispersion of matrix elastin, and attenuated lung structural abnormalities noted in vehicle-treated mice after 24 hours of MV-O₂. These findings suggest that elastin breakdown contributes to defective lung growth in response to MV-O₂ and might be targeted therapeutically to prevent MV-O₂-induced lung injury.
-
Am. J. Respir. Crit. Care Med. · Sep 2011
Comparative StudyRelationship between group-specific component protein and the development of asthma.
Airway inflammation and remodeling during asthma are attributed to the altered expression of biologically relevant proteins. ⋯ Gc may be involved in the development of asthma, and the neutralization of Gc protein could be a therapeutic strategy for asthma.