China
Africa
Explore chapters and articles related to this topic
The Effect of Anti-Asthmatic Drugs on Airway Hyperresponsiveness and Inflammation
Published in Devendra K. Agrawal, Robert G. Townley, Inflammatory Cells and Mediators in Bronchial Asthma, 2020
Patients with asthma have an increased responsiveness to many physical and chemical stimuli.6 Bronchial hyperresponsiveness is therefore regarded as a major pathophysiological characteristic of this disease. In vitro investigations in man show that there are interindividual differences in the responsiveness of isolated bronchial smooth muscle, but that these differences cannot explain the hyperresponsiveness in asthmatics. In most studies there is a very poor correlation between in vivo and in vitro responsiveness of the airways.7–9 These findings therefore suggest that the increased airway responsiveness observed in vivo in asthmatics cannot be explained by an intrinsic abnormality of the bronchial smooth muscle. Other factors such as changes in the autonomic nervous system and the presence of airway inflammation may contribute to the altered airway responsiveness.10,11
An Overview of Experimental Methods
Published in Richard Beasley, Neil E. Pearce, The Role of Beta Receptor Agonist Therapy in Asthma Mortality, 2020
All of the aforementioned studies have involved acute effects of beta agonists. More recently, some studies have reported deterioration in lung function with long-term use of regular beta agonists.68 The underlying cause for such occurrences is not known, although they may relate to increases in bronchial hyperresponsiveness. However, not all studies with regular beta agonist use have been able to demonstrate deterioration in lung function,23,69 and it may relate to certain beta agonists, such as isoprenaline and fenoterol.22,23,68 Study designs to assess the underlying mechanism and incidence of potential deterioration in respiratory function are difficult to define. At present, such basic questions as what dosage constitutes regular use sufficient to downregulate beta receptors and duration of treatment, remain elusive. Studies with enantiomers instead of racemic mixtures may also be relevant in assessing this problem.70 Plainly it is of major importance with the introduction of new long-acting beta agonists, such as salmeterol and formoterol.
Bronchial Asthma and Idiopathic Pulmonary Fibrosis as Potential Targets for Hematopoietic Stem Cell Transplantation
Published in Richard K. Burt, Alberto M. Marmont, Stem Cell Therapy for Autoimmune Disease, 2019
Júlio C. Voltarelli, Eduardo A. Donadi, José A. B. Martinez, Elcio O. Vianna, Willy Sarti
Bronchial hyperresponsiveness is defined as an increased ability of the airway to narrow its caliber after exposure to nonspecific stimuli, including bronchoconstrictor pharmacologic agonists, such as histamine, acethylcholine, methacoline, and many other stimuli. After nonspecific stimuli provocation, patients presenting with bronchial hyperresponsiveness exhibit a 20% fall in the forced expiratory volume in the first second (FEV1). Usually, the magnitude of airway hyperresponsiveness correlates with the severity of asthma and with variations of the peak expiratory flow rate. An improvement in FEV1 may be observed after the inhalation of bronchodilators. The development of bronchial hyperresponsiveness in asthmatics has been associated with persistent airway inflammation, mainly caused by the activation of inflammatory cells such as mast cells, eosinophils, neutrophils and lymphocytes. Although the mechanisms responsible for airway hyperresponsiveness are not completely understood, the consequences of the persistent inflammation include airway wall thickening, loss of airway epithelium, airway edema, and altered airway smooth muscle function.21
Development, validation and application of a questionnaire to qualify the indoor environmental exposure of patients with respiratory allergy
Published in Journal of Asthma, 2023
Bárbara de Souza, Marcelo Alves Ferreira, Jorge Kalil, Pedro Giavina-Bianchi, Rosana Câmara Agondi
Certainly, the characteristics of modern indoor environments increase the duration and intensity of exposure to mites, cockroaches, animal epithelium and molds, these being the main indoor aeroallergens associated with the sensitization of patients with respiratory allergy (16,17). In recent decades, there has been also a growing evidence that exposure to common indoor aeroallergens plays an important role in the development of bronchial hyperresponsiveness. Indoor air contaminants are influenced by the architectural design of buildings, outdoor sources of pollution, and construction materials; therefore, either individually-tailored home environmental interventions could be associated with a reduction of allergen exposure that may be expected to have a direct clinical benefit (18–20).
Defining response to therapy with biologics in severe asthma: from global evaluation to super response and remission
Published in Expert Review of Respiratory Medicine, 2023
Andriana I Papaioannou, Evangelia Fouka, Konstantinos Bartziokas, Maria Kallieri, Angelos Vontetsianos, Konstantinos Porpodis, Nikoletta Rovina, Stelios Loukides, Petros Bakakos
In conclusion, the definition of super-responders to biological treatments in severe asthma remains a major concern, as, although many definitions have been proposed, there is still much divergence between the clinical perception of the super-response and the underlying severe asthma inflammation and lung function. The current classification of super-response relies mainly on standardized clinical parameters, while many of these criteria are common to those of the clinical remission, leaving room for possible overlap. In this context, identification of an appropriate approach associating these two aspects of Type 2 severe asthma could aid in treating physicians to understand those factors that best characterize a greater response to biologic therapies. To our opinion, a simplified approach based on current evidence is preferable: A reduction of both continuous and intermittent OCS use, reduction, or elimination of exacerbations, some degree of lung function improvement and patient’s subjective perception of symptom response may constitute the domains defining super-responders [54,77,106–110]. To the same extent, the complete absence of symptoms and exacerbations, stabilization of lung function, no or minimal use of maintenance therapy, suppressed T2 inflammation and, ideally, elimination of bronchial hyperresponsiveness should address the remission definition [111–114].
Alpha-1 antitrypsin deficiency is significantly associated with atopy in asthmatic patients
Published in Journal of Asthma, 2022
M. Aiello, A. Frizzelli, R. Pisi, A. Fantin, M. Ghirardini, L. Marchi, I. Ferrarotti, G. Bertorelli, A. Percesepe, A. Chetta
A higher percentage of our asthmatic AATD subjects self-reported allergic manifestations, consistently with current literature (6). Notably, our results showed that the majority of asthmatic patients with AATD had a higher cutaneous hypersensitivity to common seasonal aeroallergens vs. perennial aeroallergens but without reaching a statistical significance, probably due to the small number of subjects included in subgroups. These results are consistent with other studies showing a prevalence of 1–40% of seasonal allergic rhinitis vs. 1–18% of perennial allergic rhinitis in the general population (23,24). The percentage of atopy and non-atopy in our asthmatic patients was 74% vs. 26% respectively. Burrows et al. found that the prevalence of atopy was about 40% in a general population study vs. 72% in asthmatic patients (25). The study by Postma et al. found a genetic susceptibility that contributes to bronchial hyperresponsiveness and atopy and that they are closely associated with bronchial inflammation, critical in the pathogenesis of asthma (26).