We measured respiratory input impedance (1-25 Hz) in mice and obtained parameters for airway and tissue mechanics by model fitting. Lung volume was varied by inflating to airway opening pressure (Pao) between 0 and 20 cm H2O. The expected pattern of changes in respiratory mechanics with increasing lung volume was seen: a progressive fall in airway resistance and increases in the coefficients of...

In eight normal and eight asthmatic subjects airway responsiveness to methacholine was measured by means of partial flow-volume loops at 0800 and 1800 hours on the same day. Airway responsiveness was lower in the evening in both normal and asthmatic subjects.

Airway responsiveness and variability in peak expiratory flow (PEF) are widely used as objective diagnostic measures of asthma, but it is not clear how these variables should be calculated or adjusted to obtain the highest diagnostic validity for physician-diagnosed asthma in the community. Data from a community-based sample of 1,513 adults has been used. Airway responsiveness to methacholine a...

The technique of sampling exhaled air is attractive because it is noninvasive and so allows repeated sampling with ease and no risk for the patient. Knowledge of the biomarkers' origin is important to correctly understand and interpret the data. Endogenous particles, formed in the airways, are exhaled and reflect chemical composition of the respiratory tract lining fluid. However, the formation...

A 4.2-kg full-term male infant underwent treatment of acute respiratory distress as a result of gross bilateral pneumothoraces, pneumomediastinum and interstitial emphysema. When a trial of continuous positive airway pressure failed conventional intermittent positive pressure ventilation was instituted, but this also failed to achieve satisfactory ventilation at a respiratory frequency of 60 b....

Regulation of cystic fibrosis transmembrane regulator (CFTR) and epithelial sodium channel (ENaC) in airway epithelia strongly influences the rate of mucociliary clearance (MCC) by determining the volume of airway surface liquid. MCC increases in response to stimuli originating on the airway surface, and CFTR and ENaC in airway epithelia appear to be regulated by local rather than systemic sign...

In obese people, the presence of adipose tissue around the rib cage and abdomen and in the visceral cavity loads the chest wall and reduces functional residual capacity (FRC). The reduction in FRC and in expiratory reserve volume is detectable, even at a modest increase in weight. However, obesity has little direct effect on airway caliber. Spirometric variables decrease in proportion to lung v...

Objectives The aim of the study was to analyse differences in pharyngeal airway dimensions and head posture between obstructive sleep apnea patients with and without morphological deviations in the upper cervical spine and to analyse associations between pharyngeal airway dimensions and head posture in the total sample. Material and Methods The sample comprised 53 obstructive sleep apnea (OSA...

BACKGROUND Pulmonary impairment in patients suffering ulcerative colitis (UC) has been suggested by several investigators using standard pulmonary function tests (PFTs). This changes in pulmonary function associated with minimal respiratory symptoms have been documented, especially in patients with active disease. The aim of this prospective study was to determine airway resistance and lung vol...