Exhaled breath condensate detects baseline reductions in chloride and increases in response to albuterol in cystic fibrosis patients.

Impaired ion regulation and dehydration is the primary pathophysiology in cystic fibrosis (CF) lung disease. A potential application of exhaled breath condensate (EBC) collection is to assess airway surface liquid ionic composition at baseline and in response to pharmacological therapy in CF. Our aims were to determine if EBC could detect differences in ion regulation between CF and healthy and measure the effect of the albuterol on EBC ions in these populations.

Effects of an inhaled β2-agonist on cardiovascular function and sympathetic activity in healthy subjects.

Study Objective: To determine the effect of a short-acting, inhaled β(2)-adrenergic receptor agonist, albuterol sulfate, administered by nebulization, on cardiovascular function and sympathetic activity in healthy individuals.

Design: Prospective, placebo-controlled, single-blind, crossover study.

Setting: University research center.

Genetic variation of αENaC influences lung diffusion during exercise in humans.

Exercise, decompensated heart failure, and exposure to high altitude have been shown to cause symptoms of pulmonary edema in some, but not all, subjects, suggesting a genetic component to this response. Epithelial Na(+) Channels (ENaC) regulate Na(+) and fluid reabsorption in the alveolar airspace in the lung. An increase in number and/or activity of ENaC has been shown to increase lung fluid clearance.

Genetic variation of the alpha subunit of the epithelial Na+ channel influences exhaled Na+ in healthy humans.

Epithelial Na(+) channels (ENaC) are located in alveolar cells and are important in β(2)-adrenergic receptor-mediated lung fluid clearance through the removal of Na(+) from the alveolar airspace. Previous work has demonstrated that genetic variation of the alpha subunit of ENaC at amino acid 663 is important in channel function: cells with the genotype resulting in alanine at amino acid 663 (A663) demonstrate attenuated function when compared to genotypes with at least one allele encoding threonine (T663, AT/TT). We sought to determine the influence of genetic variation at position 663 of ENaC on exhaled Na(+) in healthy humans.

Variability in measures of exhaled breath na, influence of pulmonary blood flow and salivary na.

The assessment of inflammatory markers and ions in exhaled breath condensate (EBC) is being utilized more frequently in diseases such as asthma and cystic fibrosis with marked variability in EBC measures, including those of exhaled Na(+). We sought to determine if variability in exhaled Na(+) was due to differences in pulmonary blood flow (PBF) or Na(+) in the mouth (salivary Na(+)). We measured exhaled Na(+) three times with coinciding sampling of salivary Na(+) and assessment of PBF (using acetylene rebreathing) in 13 healthy subjects (54% female, age = 27 ± 7 yrs.

Impaired lung diffusing capacity for nitric oxide and alveolar-capillary membrane conductance results in oxygen desaturation during exercise in patients with cystic fibrosis.

Background: Exercise has been shown to be beneficial for patients with cystic fibrosis (CF), but for some CF patients there is a risk of desaturation, although the predicting factors are not conclusive or reliable. We sought to determine the relationship between the diffusion capacity of the lungs for nitric oxide and carbon monoxide (DLNO and DLCO) and the components of DLCO: alveolar-capillary membrane conductance (D(M)), and pulmonary capillary blood volume (V(C)) on peripheral oxygen saturation (SaO(2)) at rest and during exercise in CF.

Methods: 17 mild/moderate CF patients and 17 healthy subjects were recruited (age=26±7 vs.

Glycemic control influences lung membrane diffusion and oxygen saturation in exercise-trained subjects with type 1 diabetes: alveolar-capillary membrane conductance in type 1 diabetes.

Lung diffusing capacity (DLCO) is influenced by alveolar-capillary membrane conductance (D (M)) and pulmonary capillary blood volume (V (C)), both of which can be impaired in sedentary type 1 diabetes mellitus (T1DM) subjects due to hyperglycemia. We sought to determine if T1DM, and glycemic control, affected DLNO, DLCO, D (M), V (C) and SaO(2) during maximal exercise in aerobically fit T1DM subjects. We recruited 12 T1DM subjects and 18 non-diabetic subjects measuring DLNO, DLCO, D (M), and V (C) along with SaO(2) and cardiac output (Q) at peak exercise.

Glycemic status affects cardiopulmonary exercise response in athletes with type I diabetes.

Purpose: This study aimed to (a) examine the influence of type I diabetes on the cardiopulmonary exercise response in trained subjects and (b) determine whether glycemic control affects these responses.

Methods: The cardiopulmonary responses to maximal incremental cycle ergometry were compared in 12 Ironman triathletes with type I diabetes and 10 age- and sex-matched control subjects without diabetes. Athletes with type I diabetes were then stratified into low- (glycosylated hemoglobin (HbA1c) < 7%, n = 5) and high-HbA1c (HbA1c > 7%, n = 7) groups for comparison.