Methacholine challenge studies are often conducted to diagnose asthma in patients with mild or intermittent respiratory symptoms when screening spirometry results are normal. We hypothesized that in patients with increased nonspecific bronchial hyperreactivity (NSB-HR), gas trapping might be present and that this information could be a factor in clinical decision making. To assess the relations...

The response to inhaled methacholine is increased in patients with chronic airflow obstruction, but it is not known whether this is due to true hyperresponsiveness or is a result of the airflow obstruction. In asthmatics the response to methacholine correlates with the bronchoconstriction produced by hyperventilation of cold dry air. We studied 27 patients with a history of smoking and chronic ...

INTRODUCTION Circulating microRNAs (miRNA) are promising biomarkers for human diseases. Our study hypothesizes that circulating miRNA would reveal candidate biomarkers related to airway hyperresponsiveness (AHR) and provide biologic insights into asthma epigenetic influences. METHODS Serum samples obtained at randomization for 160 children in the Childhood Asthma Management Program were profi...

To evaluate the effect of chronic airway inflammation on cough sensitivity and bronchial responsiveness, we measured the cough threshold to tartaric acid and bronchial responsiveness to methacholine (PC20-FEV1) in 13 asthmatic, 13 bronchitic (sino-bronchial syndrome) and 49 healthy non-atopic subjects. All subjects were non-smokers. The geometric mean value of the cough threshold was 9.55, 5.62...

STUDY OBJECTIVE The duration of action of several new non-sedative antihistamine preparations as assessed by skin and bronchial reactivity to histamine has still not been well established. The aim of the study was to evaluate the duration of effect of loratadine (10 mg) and terfenadine (120 mg) administered once a day for one week on cutaneous and inhaled reactivity to histamine by comparison w...

PURPOSE Bronchial hyperresponsiveness (BHR) is typically measured by bronchial challenge tests that employ direct stimulation by methacholine or indirect stimulation by adenosine 5'-monophosphate (AMP). Some studies have shown that the AMP challenge test provides a better reflection of airway inflammation, but few studies have examined the relationship between the AMP and methacholine challenge...

The aim of this study was to investigate the effect of inhaled budesonide on modifications of the provocative concentration of agonist causing a 20% fall in forced expiratory volume in one second (FEV1) (PC20) and maximal response plateau to inhaled methacholine during the pollen season in pollen-sensitive subjects with mild asthma. The effects of inhaled budesonide (800 micrograms.day-1) on th...

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The effect of a selective thromboxane synthetase inhibitor, OKY-046, and a selective 5-lipoxygenase inhibitor, AA-861, on bronchial responsiveness to acetylcholine was studied in 23 asthmatic subjects. The provocative concentration of acetylcholine producing a 20% fall in forced expiratory volume in one second (PC20 FEV1) was measured before and after oral administration of OKY-046 (3000 mg ove...

We have shown previously that female sex is a determinant of cough sensitivity to inhaled capsaicin, but the relationship between atopy and the cough sensitivity has not been examined. The capsaicin cough threshold, defined as the lowest concentration of capsaicin causing five or more coughs, nonspecific bronchial responsiveness, defined as the provocative concentration of methacholine causing ...