Search results for "Acholi"
showing 10 items of 71 documents
The effect of challenge method on methacholine-induced changes in sensitivity and air trapping
2010
Summary Background The methacholine challenge test performed with the tidal breathing method induces a greater fall in FEV 1 than the dosimeter method; however, the effect of the challenge method on methacholine-induced fall in FVC has not been investigated. Objective To determine the influence of the challenge method on methacholine-induced changes in FEV 1 and FVC. Methods Airway responsiveness to methacholine was determined by dosimeter method and tidal breathing method in 37 subjects with suspected asthma. The dosimeter was modified to deliver an identical volume to that obtained with the tidal breathing method and the same nebulizer model was used for the two challenges. The response w…
Exhaled Nitric Oxide Measurement Is Not Useful for Predicting the Response to Inhaled Corticosteroids in Subjects With Chronic Cough
2009
Background Increased concentrations of exhaled nitric oxide (ENO) are identified predominantly in subjects with chronic cough due to conditions that habitually respond well to therapy with inhaled corticosteroids (ICSs). The aim of this study was to assess the usefulness of ENO in predicting the response to ICS therapy in subjects with chronic cough and to determine the relationship between either methacholine or adenosine 5′-monophosphate (AMP) responsiveness and the response to ICS therapy. Methods A total of 43 patients with chronic cough were studied. During the baseline period, ENO measurement, spirometry, and concentration-response studies with both methacholine and AMP were performed…
The Lack of the Bronchoprotective and Not the Bronchodilatory Ability of Deep Inspiration Is Associated with Airway Hyperresponsiveness
2001
In healthy subjects, deep inspiration (DI) acts both as a bronchodilator and a bronchoprotector. The latter is impaired in asthmatics. We have now evaluated whether the lack of bronchoprotection is related to bronchial hyperresponsiveness (BHR), and whether the bronchodilatory effect is also lost in asthmatics. Ten healthy subjects (PC20 > 75 mg/ml), 12 asthmatics with moderate to severe BHR (PC20 < 1 mg/ml), 14 asthmatics with mild to borderline BHR (1 < PC20 < 25 mg/ml), and 10 rhinitics with mild to borderline BHR (1 < PC20 < 25 mg/ml) underwent single-dose methacholine provocations inducing at least 20% reduction in FEV1 after 20 min of DI inhibition. To measure the bronchodilatory effe…
Effect of Salmeterol on Seasonal Changes in Airway Responsiveness and Exhaled Nitric Oxide in Pollen-Sensitive Asthmatic Subjects
2002
Objective Using a model of natural allergen exposure, we examined the effect of regular treatment with salmeterol on allergen-induced changes in airway responsiveness and exhaled nitric oxide (ENO). Design Double-blind, randomized, parallel-group study. Setting Specialist allergy unit in a university hospital. Patients Asthmatic patients sensitized to pollen allergens were randomly allocated to monotherapy with salmeterol (n = 14) or placebo (n = 13). Interventions Salmeterol, 25 μg, and placebo inhalers, two puffs bid, for 6 weeks. Measurements Spirometry, the level of a provocative concentration of a substance (methacholine) causing a 20% fall in FEV 1 (PC 20 ), the PC 20 level for adenos…
Differences in sensitivity, maximal response and position of the concentration-response curve to methacholine between asthmatics, patients with aller…
1998
The aim of this study was to detect differences in maximal response and position of the concentration-response curves to methacholine between asthmatics and subjects with allergic rhinitis. A total of 228 adults (107 mild asthmatics, 96 allergic rhinitics and 25 healthy control subjects) were challenged with methacholine. The test was interrupted when FEV1 dropped by more than 40% or when the highest concentration of methacholine (200 mg ml-1) had been administered. Concentration-response curves were characterized by their PC20 (concentration of methacholine that produced 20% fall in FEV1 = airway sensitivity), and if possible, by their EC50 (concentration of methacholine that produced 50% …
Determinants of bronchial hyperresponsiveness in subjects with rhinitis.
2005
Subjects with rhinitis but without asthma may have coexisting bronchial hyperresponsiveness, although the reasons for this are uncertain. To evaluate the factors that determine BHR in rhinitis we examined 410 patients with symptomatic rhinitis with forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) ≥ 80% of the predicted value. In all subjects a skin prick test (SPT) was performed, a determination of total serum IgE and an eosinophils count in the blood. Of the 410 subjects we found that 161 (39.3%) exhibited a methacholine PD20 of 800 mg or less (Group A), whereas 249 (60.7%) had a methacholine PD20 more of 800 mg (Group B). Despite the matched mean values for FEV…
The bronchodilation response to deep inspiration in asthma is dependent on airway distensibility and air trapping
2011
In healthy individuals, deep inspirations (DIs) have a potent bronchodilatory ability against methacholine (MCh)-induced bronchoconstriction. This is variably attenuated in asthma. We hypothesized that inability to bronchodilate with DIs is related to reduced airway distensibility. We examined the relationship between DI-induced bronchodilation and airway distensibility in 15 asthmatic individuals with a wide range of baseline lung function [forced expired volume in 1 s (FEV1) = 60–99% predicted]. After abstaining from DIs for 20 min, subjects received a single-dose MCh challenge and then asked to perform DIs. The effectiveness of DIs was assessed by the ability of the subjects to improve …
Effects of exercise training on airway closure in asthmatics
2012
We previously reported that responsiveness to methacholine (Mch) in the absence of deep inspiration (DI) decreased in healthy subjects after a short course of exercise training. We assessed whether a similar beneficial effect of exercise on airway responsiveness could occur in asthmatics. Nine patients (male/female: 3/6; mean age ± SD: 24 ± 2 yr) with mild untreated asthma [forced expiratory volume in 1 s (FEV1): 100 ± 7.4% pred; FEV1/vital capacity (VC): 90 ± 6.5%] underwent a series of single-dose Mch bronchoprovocations in the absence of DI in the course of a 10-wk training rowing program (6 h/wk of submaximal and maximal exercise), at baseline ( week 0), and at week 5 and 10. The singl…
Reduced airway responsiveness in non elite runners
2005
Med Sci Sports Exerc. 2005 Dec;37(12):2019-25. Reduced airway responsiveness in nonelite runners. Scichilone N, Morici G, Marchese R, Bonanno A, Profita M, Togias A, Bonsignore MR. SourceInstitute of Medicine and Pneumology, Respiratory Unit; University of Palermo, Italy. n.scichilone@libero.it Abstract PURPOSE: The effects of endurance training on airway responsiveness in nonasthmatic subjects are poorly defined. We hypothesized that airway responsiveness may differ between none-lite endurance athletes and sedentary subjects, and studied healthy, nonelite runners and sedentary controls by single-dose methacholine challenges carried out in the absence of deep inspirations, in that deep insp…
Glycopyrronium bromide blocks differentially responses mediated by muscarinic receptor subtypes.
1993
To analyse the potency of glycopyrronium bromide in blocking responses mediated via subtypes of muscarinic receptors in vitro, we tried to determine its equilibrium dissociation constants at prejunctional muscarinic receptors inhibiting the twitch response of rabbit vas deferens (presumed M1 type), at M2 (paced at left atria), M3 (guinea pig ileum) muscarinic receptor subtypes and at the muscarinic receptor of the rabbit iris sphincter (not M1-M4, not m5). Glycopyrronium bromide shifted to the right the curve for inhibition of the twitch response induced by the agonist McN-A-343, and the methacholine-induced curves for inhibition of rat atrial contraction, and for tonic contraction of guine…