Allergen avoidance at high altitude and urinary eosinophil protein X.
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Adolescent↗
Biomedical subjects
D G Peroni
Publications and source records attributed to D G Peroni.
Prevalence of asthma and respiratory symptoms in childhood in an urban area of north-east Italy.
In the present study we have assessed the prevalence of asthma-related symptoms in school children resident in the urban area of Verona, in the north east of Italy, as part of the International Study of Asthma and Allergies in Childhood (ISAAC). The entirely of the population of children aged 6-7 yrs (total 2,350, from 64 schools) and 13-14 years (total 2,500 from 42 schools) living in the area was selected. A questionnaire was distributed at school. This was addressed to the parents of the younger population and distributed directly to the older children. In the two groups 2,091 (89%) and 2,179 (87%) questionnaires were returned, respectively. The results obtained show a more frequent history of "wheeling ever" in the young population compared to the older group (23.2 versus 7.9%, respectively) (p < 0.001). There was no difference in the prevalence of wheezing in the last 12 months (7.3 and 7.4%, respectively), and of asthma (4.6 and 3.5%, respectively). In the older group there was a higher incidence of exercise-induced wheezing (12.0 versus 3.2%), which was particularly significant in the females compared to males (14.2 versus 10.0, respectively; p < 0.01). Our data confirm that there is a marked variation in the prevalence of asthma and asthma-related respiratory symptoms in different centres throughout the world, since we obtained a lower percentage of reported symptoms in comparison to other ISAAC centres.
Adolescent↗
Exercise-induced asthma: is there space for late-phase reactions?
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Asthma, Exercise-Induced↗
Expression of CD44 and integrins in bronchial mucosa of normal and mildly asthmatic subjects.
We have investigated the expression of cell surface markers and leucocyte cell adhesion molecules by immunohistochemistry in bronchial biopsies from 10 mild atopic asthmatics and 8 normal, nonatopic subjects. Significantly increased numbers of eosinophils (p<0.01) were evident in the bronchial submucosa of asthmatic subjects. In epithelium there were more CD44+ (p<0.02) and lymphocyte function-associated antigen-1 (LFA-1)+ (p<0.06) leucocytes in asthmatics than in normal subjects. Bronchial epithelial cells stained positively with anti-CD44 monoclonal antibodies (moAb) in both groups; however, when the staining was expressed as percentage of the total basement membrane, a considerable and highly significant increase was observed in the asthmatics (median 80 vs 22%, p=0.003). Few leucocytes were positive for very late activation antigen (VLA)-1, VLA-2 and VLA-4. The moAb for VLA-6 stained the basement membrane of the bronchial epithelium; while intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) were constitutively expressed in endothelium. A positive correlation was found between LFA-1+ cells and activated eosinophils (EG2+) in the submucosa (p<0.005; r(s)=0.80). We conclude that even in mild asthma there is evidence of increased expression of cell surface ligands, and suggest that adhesive mechanisms play a role both in cell recruitment and disease activity.
Adult↗
The effect of cetirizine on the integrin-dependent respiratory burst of normodense eosinophils.
It has been proposed that cetirizine inhibits eosinophil migration and adherence. We evaluated the possible effect of cetirizine on integrin-induced eosinophil proinflammatory activation. Normodense eosinophils were triggered with monoclonal antibodies to integrins in the presence of different concentrations of certirizine. Proinflammatory activation was measured by evaluation of O2- production. Only at high concentrations (250 micrograms/ml) and in the first 15 min did certirizine significantly inhibit (p < 0.02) the eosinophil respiratory burst. No effect was shown for lower concentrations (50 and 100 micrograms/ml) or after 15 min. These data suggest that, only at very high concentrations, cetirizine may induce a transient inhibition of the integrin-induced eosinophil respiratory burst.
Antibodies, Monoclonal↗
Double-blind trial of house-dust mite immunotherapy in asthmatic children resident at high altitude.
Twenty-three Dermatophagoides pteronyssinus (Dpt)-sensitive asthmatic children aged 7-14 years entered a double-blind, placebo-controlled trial of standardized immunotherapy (IT) (Alpare) while resident at high altitude. Dpt sensitivity was evaluated by skin prick tests at different allergen concentrations at the enrollment and after 6 and 12 months of treatment. Bronchial hyperreactivity was evaluated at the same time points, and on each occasion, histamine challenge and, the following day, Dpt bronchial challenge were performed. All patients, irrespective of active treatment, improved clinically and in lung function with increased PC20 and Dpt-PD20. Alpare-treated patients had a significantly decreased sensitivity on Dpt skin testing (P < 0.009) and felt that their asthma had improved (P < 0.001) compared with placebo-treated subjects, but there was no difference between the treatment groups in lung function or bronchial challenge response. IT neither increased nor decreased bronchial histamine sensitivity. Our results indicate that Dpt IT benefits asthmatic children, but improvement by allergen avoidance at high altitude is even greater.
Adolescent↗
Effective allergen avoidance at high altitude reduces allergen-induced bronchial hyperresponsiveness.
We studied the effects of reduced allergen exposure on bronchial hypereactivity (BHR) in two groups of asthmatic children allergic to house dust mites (HDM) living at high altitude for 9 continuous mo. In the first group the serum levels of total and HDM-specific IgE showed significant decreases after 3 mo (p < 0.001 and p < 0.02, respectively) and after 9 mo (p < 0.001). Three months after returning home the total IgE levels had increased significantly (p < 0.001). The mean percentage fall in peak expiratory flow after exercise testing improved after 3 and 9 mo (p < 0.05), but it had deteriorated after 3 mo at home (p < 0.01). The methacholine PD20-FEV1 increased after 3 mo (p = 0.001) and further after 9 mo (p < 0.001), with a decrease after the 3-mo period at sea level (p = 0.01). In the second cohort there was a significant increase in HDM PD20-FEV1 after 6 and 9 mo (p < 0.001), with a slight decrease of magnitude of the allergen-induced late reaction. Histamine PD20-FEV1 significantly increased after 6 and 9 mo at high altitude, particularly in the challenges performed after the HDM bronchial provocation (p < 0.01). Our data demonstrate that allergen avoidance in asthmatic children not only decreases nonspecific BHR but also decreases allergen sensitivity, late allergen-induced bronchial reactions, and enhancement of BHR by allergen challenge.
Allergens↗
Influence of allergen avoidance at high altitude on serum markers of eosinophil activation in children with allergic asthma.
A cohort of 12 asthmatic children was followed over several months, during which they moved back and forth from an allergen-free to an allergen-rich environment at high and low altitude, respectively. The children were treated with non-steroidal anti-asthmatic drugs as clinically needed. Histamine PC20-FEV1 was unaltered during the study period, whereas serum levels of eosinophil cationic protein (ECP) and eosinophil protein X (EPX) showed significant changes when the children were exposed to the offending allergens. The total IgE significantly increased during exposure. The serum levels of myeloperoxidase (MPO) as well as of chemotactic factors for both neutrophils and eosinophils were unaltered during allergen exposure. We conclude that the serum markers of eosinophil activity ECP and EPX are sensitive indices of allergen exposure in asthmatic atopic children.
Adolescent↗
Effects of nedocromil sodium on the binding of N-formyl-methionyl-leucyl-phenylalanine in human neutrophils.
In the present study the inhibition by nedocromil sodium of the specific receptor binding of FMLP was evaluated in human neutrophils (PMNs) using a FMLP-(3H) binding assay. The time course of the binding was markedly influenced by nedocromil sodium used at a concentration of 300 microM. No significant inhibition was obtained when the cells were treated with nedocromil sodium 3 microM or with sodium cromoglycate 300 microM. FMLP binding is essentially eliminated by the highest dose of nedocromil sodium. The biologic meaning of this effect in asthmatic patients should be further evaluated.
Anti-Inflammatory Agents, Non-Steroidal↗
Inhibition of different dosages of oxatomide or placebo on skin prick test and nasal allergen provocation.
In this two-stage, double-blind study, we evaluated the effects of different dosages of oxatomide (1 and 2 mg/kg/day) on nasal provocation and skin reaction wheal induced by grass-pollen challenge. Children with a positive history of allergic rhinoconjunctivitis and positive responses to skin prick test and nasal provocation test to grass pollen were studied out of season. The results obtained with 1 mg/kg/day of oxatomide demonstrated no significant difference in wheal areas and nasal secretion induced by allergen challenge between treated and untreated patients. The administration of 2 mg/kg/day demonstrated a significant suppression in wheal reaction and nasal secretion induced by specific challenge.
Adolescent↗
Double-blind evaluation of effectiveness and safety of flunisolide aerosol for treatment of bronchial asthma in children.
A double-blind study was carried out in 20 asthmatic children in order to evaluate the therapeutic efficacy and safety of inhaled corticosteroid flunisolide. 0.5 mg of the drug was administered by a jet nebulizer twice daily for 2 months. Respiratory symptoms, pulmonary function values and methacholine PC20-FEV1 were evaluated, as also morning cortisol levels, plasma cortisol increase after ACTH test, and 24-h urinary cortisol excretion. The data obtained show the efficacy of the drug in reducing symptoms. No significant difference was observed in pulmonary function values and in bronchial reactivity results between the two groups. No effect of flunisolide was observed on hypothalamic-pituitary-adrenal function. This study confirms the efficacy and safety of flunisolide (0.5 mg b.i.d.) in the treatment of asthmatic children.
Adolescent↗
Theophylline inhibition of BCG-induced pulmonary inflammatory responses.
The present study was performed to evaluate the effect(s) of theophylline on BCG-induced pulmonary inflammatory responses in an experimental rat model system. Five groups of six animals each received the following: group 1: theophylline-treated, BCG-challenged, and sacrificed three days later; group 2: saline-treated, BCG-challenged, and sacrificed three days later; group 3: theophylline-treated, BCG-challenged, and sacrificed five days later; group 4: saline-treated, BCG-challenged, and sacrificed five days later; and group 5: no treatment and no BCG-challenge ("absolute controls"). Quantitative recovery of bronchoalveolar lavage (BAL) cells was performed and compared with histopathologic changes in lung specimens from each animal in all five groups. No significant differences in quantitative BAL cellular recovery were observed in theophylline-treated animals from saline-treated controls. There was a significant reduction in BAL cell number in saline-treated animals sacrificed five days after BCG-challenge (group 4) from that seen in saline-treated animals sacrificed three days after BCG-challenge (group 2). The most striking finding, however, was a marked diminution in granuloma formation induced by theophylline five days after BCG challenge (group 3). These findings suggest an antiinflammatory effect of theophylline.
Animals↗
Changes in bronchial reactivity in asthmatic children after treatment with beclomethasone alone or in association with salbutamol.
Airway inflammation is consistently present in patients with severe asthma. The combination of inhaled steroids and bronchodilators may be useful both for treating symptoms and improving the underlying inflammatory condition. We have compared the effect of beclomethasone dipropionate (BDP) combined with salbutamol (S), BDP alone, and placebo, on the severity of bronchial responsiveness in 30 children with allergic asthma during the period of specific allergen exposure. In children treated with BDP alone, PC20-FEV1 methacholine was 0.66 +/- 0.54 at the beginning and 1.91 +/- 2.11 at the end of the study period (p greater than 0.05). In children treated with BDP + S PC20, methacholine was 1.21 +/- 1.43 at the beginning and 4.22 +/- 3.88 at the end of the study (p less than 0.05). The group of children treated with placebo had a PC20-FEV1 methacholine of 0.79 +/- 0.61 at the beginning of the study and 0.80 +/- 0.46 at the end of the study. The results of the present study show that maintenance treatment with inhaled beclomethasone combined with salbutamol may lead to greater improvement in bronchial hyperreactivity than treatment with inhaled beclomethasone dipropionate alone.
Adolescent↗
Efficacy and duration of action of placebo responses in the prevention of exercise-induced asthma in children.
Exercise-induced bronchoconstriction, a common phenomenon in asthmatic children, may be prevented by the administration of appropriate drugs. In this study we evaluated the effect and duration of action of placebo (Freon gasses) administered to the patients as a protective drug. The maximum decrease in forced expiratory volume in 1 second (FEV1) after exercise testing was 40.3% +/- 3.10 at the initial screening session and, on different study days, 23.3% +/- 3.57, 28.8% +/- 3.86, and 33.7% +/- 3.71 30, 120, and 240 minutes, respectively, after the administration of Freon gasses. There was a linear trend indicating a reduction in protection with time. The placebo effect was marked 30-120 minutes after treatment (p less than 0.01) and completely disappeared after 4 hours. The placebo effect should always be considered in the evaluation of any new antiasthmatic drug.
Adolescent↗
[Beta-2 agonists, exposure to allergens and bronchial hyperreactivity in children with allergic asthma].
The contribution of beta 2-agonist treatment per se and the effect of beta 2-agonists plus allergen exposure was evaluated in two groups of thirteen asthmatic children being treated respectively at sea level during the period of maximal allergen exposure and at high altitude in an environment free of the offending allergens. Bronchial hyperreactivity was evaluated by standardised exercise tests before and after treatment with salbutamol controlled release tablets (4 mg). Challenges were performed at the beginning and after 2 and 4 weeks of treatment. A fourth test was performed 2 days after stopping the treatment. Children treated with salbutamol at sea level (exposure to allergen) showed baseline delta PEF of 16.9 +/- 3.4 and 13.7 +/- 4.2, 20.7 +/- 4.3, 26.0 +/- 5.1 respectively for the second, third and fourth test. Children treated at high altitude showed respectively delta PEF of 34.9 +/- 5.1, 31.1 +/- 4.9, 26.5 +/- 5.4, 27.9 +/- 5.0. These data suggest that oral salbutamol per se is not responsible for an increase in bronchial responsiveness, but eventually suggest that treatment with beta 2-agonists at the same time as continued allergen exposure may be responsible for an increase in bronchial hyperresponsiveness.
Administration, Oral↗