Search results for "BRONCHIAL HYPERRESPONSIVENESS"
showing 10 items of 12 documents
Bronchial reactivity and intracellular magnesium: a possible mechanism for the bronchodilating effects of magnesium in asthma
1998
1.Increased bronchial smooth muscle contractility with consequent bronchial hyperreactivity are characteristic physiopathological events of asthma. Since magnesium intervenes in calcium transport mechanisms and intracellular phosphorylation reactions, it constitutes an important determinant of the contraction/relaxation state of bronchial smooth muscle. In the present study we investigated the relationship between bronchial reactivity, assessed by methacholine-provocation test, and magnesium concentrations both at extracellular and intracellular levels measured by spectrophotometry. Twenty-two patients with mild-to-moderate asthma and 38 non-asthmatic subjects with allergic rhinitis (24 all…
No evidence for a correlation of glutathione S-tranferase polymorphisms and chronic rhinosinusitis.
2011
OBJECTIVE: Cellular detoxification mechanisms are mandatory for cellular protection against oxidative stress and reactive oxygen species. One major group of antioxidative active enzymes involved in cellular detoxification are the Glutathione S-Transferases (GST). Multiple subtypes like GSTM1, GSTP1, and GSTT1 and variants of them are known, arising from allelic variations of the GST loci. Moreover, functional variants occur in high percentages and have been associated with diseases like bronchial asthma and bronchial hyperresponsiveness. The interplay of oxidative stress, detoxifying genes like GSTs and the genesis of respiratory tract illness is under contradictory debate. In this study, w…
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…
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…
Understanding the complexity of IgE-related phenotypes from childhood to young adulthood: A Mechanisms of the Development of Allergy (MeDALL) seminar.
2012
Mechanisms of the Development of Allergy (MeDALL), a Seventh Framework Program European Union project, aims to generate novel knowledge on the mechanisms of initiation of allergy. Precise phenotypes of IgE-mediated allergic diseases will be defined in MeDALL. As part of MeDALL, a scientific seminar was held on January 24, 2011, to review current knowledge on the IgE-related phenotypes and to explore how a multidisciplinary effort could result in a new integrative translational approach. This article provides a summary of the meeting. It develops challenges in IgE-related phenotypes and new clinical and epidemiologic approaches to the investigation of allergic phenotypes, including cluster a…
Bronchial hyperresponsiveness in children with atopic rhinitis: a 7-year follow-up
2004
Background: A high prevalence of bronchial hyperresponsiveness (BHR) was found in atopic subjects with rhinitis. Those subjects may be at higher risk for developing bronchial asthma. We evaluated, in a 7-year follow-up, BHR and atopy in a homogeneous population of nonasthmatic children with allergic rhinitis (AR), and their role in asthma development. Methods: Twenty-eight children (6–15 years) with AR were studied. At enrollment (T0), skin tests, total serum IgE assay, peak expiratory flow (PEF) monitoring and methacholine (Mch) bronchial challenge were performed. BHR was computed as the Mch dose causing a 20% forced expiratory volume (FEV)1 fall (PD20FEV1) and as dose–response slope (DR…
Asthma phenotypes identified by latent class analysis in the ISAAC phase II Spain study.
2012
SummaryBackground Classification of respiratory symptoms may help to identify different underlying asthma phenotypes reflecting differences in aetiology and prognosis of wheezing disease among children. Objective To determine childhood asthma phenotypes based on respiratory symptoms from a widely used questionnaire to further classify phenotypes in international settings. Methods Between 2000 and 2002 cross-sectional studies were performed in four centres in Spain. Parental questionnaires were used to collect information on allergic diseases in more than 4000 children aged 8–12 years. In addition, objective markers for allergic sensitization and bronchial hyperresponsiveness (BHR) were meas…
Elevation of total serum immunoglobulin E is associated with asthma in nonallergic individuals.
2000
Elevated serum immunoglobulin (Ig)E is the hallmark of atopy, and contributes to asthma and bronchial hyperresponsiveness in atopic individuals. In contrast, the significance of IgE in nonallergic subjects is less clear. The aim of the present study is to clarify a potential association of IgE and asthma in absence of clinical allergy. To this purpose 1,219 consecutive patients of a pulmonary practice were evaluated. Nonallergic patients were defined by negative skin prick test, history of atopy and specific IgE, 509 subjects (42%) were nonallergic. Among these, 80 patients (16%) had elevated total IgE levels (150 U x mL(-1)). Prevalence and severity of asthma in nonallergic subjects with I…
Theophylline suppresses the release of tumour necrosis factor-alpha by blood monocytes and alveolar macrophages.
1994
The purpose of this study was to evaluate the effect of theophylline on tumour necrosis factor-alpha (TNF-alpha) release by human blood monocytes (BMo), and rat BMo and alveolar macrophages (AM). BMo and AM were incubated in the absence or presence of theophylline, and the cell-free supernatants were harvested and tested for TNF-alpha activity by bioassay. Theophylline dose-dependently reduced TNF-alpha release by human BMo: significant inhibition was observed at 100 microns (41 +/- 5.9% of controls) and at 50 microns (59 +/- 4.8% of controls), while the inhibitory activity of theophylline at 10 microns (71 +/- 8.9% of controls) was not statistically significant. This activity was maximal a…
Airway remodeling in asthma.
2003
Chronic inflammation and remodeling may follow acute inflammation or may begin insidiously as a low-grade smoldering response, especially in the case of immune reactions. The histologic hallmarks of chronic inflammation and remodeling are as follows: (1) infiltration by macrophages and lymphocytes; (2) proliferation of fibroblasts that may take the form of myofibroblasts; (3) angiogenesis; (4) increased connective tissue (fibrosis); and (5) tissue destruction. It is clear that changes in the extracellular matrix, smooth muscle, and mucous glands have the capacity to influence airway function and reactivity in asthma patients. However, it is not known how each of the many structural changes …