Respiratory physiology & neurobiology
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Respir Physiol Neurobiol · Aug 2008
Effects of cystic fibrosis lung disease on gas mixing indices derived from alveolar slope analysis.
S(cond) and S(acin) are derived from analysis of concentration-normalized phase III slopes (Sn(III)) of a multiple breath inert gas washout. Studies in healthy and COPD subjects suggest these reflect ventilation heterogeneity in conducting and acinar airway zones respectively, but similar studies in cystic fibrosis (CF) are lacking. S(cond), S(acin) and lung clearance index (LCI, a measure of overall gas mixing efficiency) were measured in 22 adults and 18 children with CF and 17 adult and 29 child controls. ⋯ S(cond) was elevated in almost all CF patients, including children with mild disease and normal LCI. However, S(cond) did not correlate with other measurements and appeared to reach a maximum; further increase in ventilation heterogeneity being restricted to S(acin). The nature and/or severity of CF lung disease may invalidate assumptions underlying the ability to separate phase III slope analysis of ventilation heterogeneity into proximal and peripheral components, and LCI may be a better indicator of gas mixing in this population.
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Respir Physiol Neurobiol · Aug 2008
ReviewImplication of receptor for advanced glycation end product (RAGE) in pulmonary health and pathophysiology.
Receptor for advanced glycation end products (RAGE) is a membrane bound receptor and member of the immunoglobulin super family and is normally present in a highly abundant basal level expression in lung. This high expression of RAGE in lung alveolar epithelial type I (ATI) cells is presumably involved in the proliferation and differentiation of pulmonary epithelial cells. ⋯ Recently, a soluble form of RAGE (sRAGE) produced by recombinant gene technology was shown to exhibit a therapeutic potential in experimental animal models. Detailed study of RAGE in the pulmonary tissues will facilitate the understanding of the importance of RAGE signaling in the pulmonary health and pathophysiology.