Search results for "provocation"
showing 10 items of 67 documents
Deep inspiration-induced changes in lung volume decrease with severity of asthma
2007
Summary We have previously reported that the magnitude of deep inspiration (DI)-induced bronchodilation is only slightly reduced in mild asthmatics, compared to healthy subjects. The aim of this study was to evaluate whether increased severity of asthma is associated with impairment in the ability of DI to induce changes in lung volume. Thirty-six consecutive asthmatics recruited from the Pulmonary and the Allergy Outpatient Clinics of the Institute of Respiratory Diseases of the University of Palermo were divided into 3 groups: Intermittent (I), Mild Persistent (MP) and Moderate–Severe (MS), based on GINA guidelines. Single dose methacholine (Mch) bronchoprovocations were performed in the …
High-Resolution Computed Tomographic Evaluation of Airway Distensibility and the Effects of Lung Inflation on Airway Caliber in Healthy Subjects and …
2001
The effects of a deep inspiration (DI) in individuals with asthma differ from those observed in healthy subjects. It has been postulated that the beneficial effect of lung inflation is mediated by airway stretch. One hypothesis to explain the defects in the function of lung inflation in asthma is that a DI may be unable to stretch the airways. This may result from attenuation of the tethering forces between the airways and the surrounding parenchyma. In the current study, we used high-resolution computed tomography (HRCT) to examine the ability of a DI to distend the airways of subjects with asthma (n = 10) compared with healthy subjects (n = 9) at baseline and after increasing airway tone …
Inhaled Corticosteroids and the Beneficial Effect of Deep Inspiration in Asthma
2005
Deep inspiration-induced bronchoprotection and bronchodilation are impaired in asthma. We evaluated the effect of inhaled glucocorticosteroids on these phenomena. Two groups of subjects with asthma, 9 with moderate/severe hyperresponsiveness to methacholine, and 12 with mild/borderline hyperresponsiveness to methacholine, received inhaled fluticasone (880 microg daily) for 12 weeks. Serial bronchoprovocations were performed at Weeks 0, 6, and 12. The impact of deep inspirations on the airway response to methacholine was evaluated on the basis of inspiratory vital capacity and FEV(1). Fluticasone produced a wide spectrum of changes in the beneficial effects of deep inspiration, but the mean …
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…
Airway Responsiveness to Histamine in Patients Refractory to Repeated Exercise
1988
To investigate the mechanisms contributing to refractoriness in exercise-induced asthma (EIA), airway responsiveness to histamine was studied in eight asthmatic patients. Patients were included in the study on the basis of their refractory response to multiple exercise challenges. Incremental challenges with inhaled histamine were performed at rest and 40 minutes after single and paired exercise tests. The geometric mean histamine concentration required to produce a 20 percent fall in FEV1 (PC20) for the challenge after paired exercise test (4.34 mg/ml) was significantly higher (p greater than 0.001) than those for the challenges after a single exercise (1.05 mg/ml) and for the challenge at…
Exogenous and endogenous provocation of psoriasis. A contribution to the Koebner phenomenon.
1974
Previous literature reports as well as own investigations concerning exogenously and endogenously induced Koebner-reactions in psoriatics are presented. The time interval between irritation and the Koebner-reaction is emphasized. It is proposed, that the intensity of the psoriatic reaction is mediated by circulating DHEA-deficiency. Hypothetical models are presented which allow to explain the different developmental rates of psoriatic lesions in relation to the type of irritation, the area affected and the subsequent proliferative responses.
Does Experience Influence Perception of Dyspnea?
2006
OBJECTIVE: The perception of somatic sensations like dyspnea can be influenced by such factors as an individuals personality, experiences, or ability to adapt to stimuli. Our aim was to determine whether the perception of acute bronchoconstriction is different for patients with asthma and patients who have never experienced an episode of airway obstruction. PATIENTS AND METHOD: We studied 2 groups of patients. The first consisted of 24 subjects with intermittent rhinitis and asthma (10 females and 14 males) with a mean (SD) age of 25 (7) years. All reported not feeling dyspnea at rest on a Borg scale. The second group consisted of 24 subjects who only had rhinitis but no lung disease (no ep…
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 …
Immunological study of Melkersson-Rosenthal syndrome. Lack of response to food additive challenge
1995
Summary A study was made of six patients with Melkersson-Rosenthal syndrome (MRS) to establish the aetiological role of foodstuffs and/or additives and the possible associated immunological alterations. In all cases Melkersson-Rosenthal syndrome (MRS) was diagnosed both clinically and histologically, excluding other causes of orofacial granulomatosis (OFG). A detailed study of possible triggering factors was performed in all patients. Blood analysis, x-rays and cultures, were always within normal limits, with the exception of the finding of circulating immune complexes (CICs) in three patients with facial palsy associated, and C-reactive protein positivity in two patients who presented pers…