Search results for "Bronchoconstrictor Agent"
showing 9 items of 19 documents
Airways Hyperresponsiveness and the Effects of Lung Inflation
2001
Lung inflation has a beneficial effect on the airways of healthy subjects. It acts as a bronchoprotector, that is to prevent bronchoconstriction, and as a bronchodilator, in that it reverses bronchial obstruction. The bronchoprotective effect of deep inspiration is more potent than the bronchodilatory one, and the two phenomena appear to advocte different mechanisms. Asthmatics and rhinitics with airways hyperresponsiveness show an impairment in bronchoprotection induced by deep breaths, whereas the bronchodilatory effect, although reduced, is still effective. The lack of the bronchoprotective effect of deep inspiration may contribute to the development of airways hyperresponsiveness. The m…
Alterations of the beneficial effect of deep inspiration in scleroderma: relationships between lung function and imaging.
2007
<i>Background:</i> It has been postulated that the beneficial effects of deep inspiration are dependent on the magnitude of airway distension by virtue of airway to parenchyma interdependence. <i>Objective:</i> This study was designed to examine whether the changes that occur in pulmonary fibrosis affect the beneficial effect of deep inspiration. <i>Methods:</i> Thirty-one subjects with scleroderma underwent lung volume and diffusion capacity assessment as well as high-resolution computed tomography. To assess the effect of deep inspiration, each subject underwent methacholine provocations in the absence of deep breaths. When the targeted change in lung f…
Effects of exercise training on airway responsiveness and airway cells in healthy subjects.
2010
J Appl Physiol. 2010 Aug;109(2):288-94. Epub 2010 Jun 10. Effects of exercise training on airway responsiveness and airway cells in healthy subjects. Scichilone N, Morici G, Zangla D, Chimenti L, Davì E, Reitano S, Paternò A, Santagata R, Togias A, Bellia V, Bonsignore MR. SourceDept. of Internal Medicine, Div. of Pulmonology (DIBIMIS Univ. of Palermo, "Villa Sofia-Cervello" Hospital, Via Trabucco 180, 90146 Palermo, Italy. n.scichilone@libero.it Abstract Airway responsiveness to methacholine (Mch) in the absence of deep inspirations (DIs) is lower in athletes compared with sedentary individuals. In this prospective study, we tested the hypothesis that a training exercise program reduces th…
The characteristics of different diagnostic tests in adult mild asthmatic patients: Comparison with patients with asthma-like symptoms by gastro-oeso…
2007
SummaryBackgroundDiagnosing asthma cannot be always easy. It is important to consider the validity of the diagnostic tests, and/or how much more commonly they are positive in patients with asthma compared to healthy subjects and, particularly, to patients with asthma-like symptoms.ObjectiveTo evaluate the validity of diagnostic tests for asthma, in terms of sensitivity, specificity, positive and negative predictive values, in patients with bronchial asthma compared to patients affected by gastro-oesophageal reflux disease (GERD) with asthma-like symptoms, and healthy control subjects without asthma and gastro-oesophageal reflux (GER).DesignSingle-center, cross-sectional, observational study…
Maximal degree of airway narrowing induced by methacholine and adenosine monophosphate: relationship with the decrease in forced vital capacity.
2010
Background Changes in forced vital capacity (FVC) may represent an indirect method for the detection of plateau in response to inhaled bronchoconstrictor agents. Objective To determine the relationship between the level of plateau obtained with either methacholine or adenosine monophosphate (AMP) and the decrease in FVC induced by each bronchoconstrictor agent. Methods Airway responsiveness to high concentrations of methacholine and AMP was determined in patients with intermittent asthma (n = 41) or allergic rhinitis (n = 26). Furthermore, allergen-induced changes in the response to each bronchoconstrictor agent were investigated in 18 pollen-sensitive patients. Concentration-response curve…
Relationship between airway sensitivity to adenosine 5' monophosphate and the shape of the concentration-response curve to methacholine in subjects w…
2001
Abstract The objective of this study was to determine differences in airway sensitivity to adenosine 5′-monophosphate (AMP) between allergic rhinitis subjects with plateau and those without evidence of plateau on the concentration–response curves to methacholine. A total of 51 adults (38 subjects with allergic rhinitis and 13 healthy controls) were challenged with increasing concentrations of methacholine and AMP. The methacholine challenge was terminated when there was a 40% or more decrease in forced expiratory volume in 1 sec (FEV 1 ), whereas the AMP challenge was stopped when FEV 1 had fallen by more than 20%. A plateau for methacholine was detected in all 13 healthy controls and in 27…
Effects of cigarette smoke on methacholine- and AMP-induced air trapping in asthmatics.
2014
Abstract Objective: No information is available on the effect of cigarette smoke on bronchoconstrictor-induced air trapping in asthma. The aim of this study was to evaluate the additional influence of smoking on methacholine- and adenosine 5'-monophosphate (AMP)-induced air trapping in subjects with asthma.Airway responsiveness to methacholine and AMP, bronchial (J'awNO) and alveolar (CANO) nitric oxide (NO) and exhaled breath condensate pH were measured in 68 adults (23 current smokers with asthma, 23 non-smokers with asthma and 22 current or former smokers with chronic obstructive pulmonary disease; COPD). The degree of air trapping induced by each bronchoconstrictor agent was expressed b…
The bronchodilatory effect of deep inspiration diminishes with aging
2004
AbstractDeep inspirations have the ability to dilate constricted airways. The impairment of this function has been associated with the occurrence of asthmatic symptoms. We evaluated whether the bronchodilatory effect of deep inspiration (DI) is affected by aging. We tested 25 healthy subjects (median age: 54 yrs, range: 25–83 yrs). Single dose methacholine (Mch) provocations were performed in the absence of DI, which induced at least 15% reduction in inspiratory vital capacity (IVC) from baseline. The post-Mch IVC measurement was followed by 4 DIs and by another IVC (post-DI IVC). The fractional difference between post-DI IVC and post-Mch IVC represented the % bronchodilation by DI. The % b…
The airway response to deep inspirations decreases with COPD severity and is associated with airway distensibility assessed by computed tomography.
2008
In patients with mild chronic obstructive pulmonary disease (COPD), the effect of deep inspirations (DIs) to reverse methacholine-induced bronchoconstriction is largely attenuated. In this study, we tested the hypothesis that the effectiveness of DI is reduced with increasing disease severity and that this is associated with a reduction in the ability of DI to distend the airways. Fifteen subjects [Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage I–II: n = 7; GOLD stage III–IV: n = 8] underwent methacholine bronchoprovocation in the absence of DI, followed by DI. The effectiveness of DI was assessed by their ability to improve inspiratory vital capacity and forced expira…