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Biomedical subjects

Piero Maestrelli

Publications and source records attributed to Piero Maestrelli.

10 recordsLinked to original sources

Epithelial damage and angiogenesis in the airways of children with asthma.

RATIONALE: Airway remodeling and inflammation are characteristic features of adult asthma that are still poorly investigated in childhood asthma. OBJECTIVES: To examine epithelial and vascular changes as well as the inflammatory response in airways of children with asthma. METHODS: We analyzed bronchial biopsies obtained from 44 children undergoing bronchoscopy for appropriate clinical indications other than asthma: 17 with mild/moderate asthma (aged 2-15 yr), 12 with atopy without asthma (1-11 yr), and 15 control children without atopy or asthma (1-14 yr). By histochemistry and immunohistochemistry, we quantified epithelial loss, basement membrane thickness, number of vessels, and inflammatory cells in subepithelium. RESULTS: Epithelial loss and basement membrane thickness were increased in children with asthma compared with control subjects (p = 0.005 and p = 0.0002, respectively) and atopic children (p = 0.002 and p = 0.005, respectively). The number of vessels and eosinophils was increased not only in asthmatic children (p = 0.03 and p = 0.0002, respectively) but also in atopic children without asthma (p = 0.03 and p = 0.008, respectively) compared with control subjects. When we stratified the analysis according to age, we observed that children with asthma younger than 6 yr had increased epithelial loss, basement membrane thickening, and eosinophilia compared with control subjects of the same age. CONCLUSIONS: Epithelial damage and basement membrane thickening, which are pathologic features characteristic of adult asthma, are present even in childhood asthma. Other changes, such as airway eosinophilia and angiogenesis, were also observed in atopic children without asthma. These observations suggest that pathologic changes occur early in the natural history of asthma and emphasize the concept that some of these lesions may characterize atopy even in the absence of asthmatic symptoms.

Adolescent↗

Up-regulated membrane and nuclear leukotriene B4 receptors in COPD.

STUDY OBJECTIVES: We investigated the role of two leukotriene B4 (LTB4) receptors, BLT1 and peroxisome proliferator-activated receptor (PPAR)-alpha, in conferring the susceptibility to develop COPD in smokers. Proinflammatory LTB4 activities are mediated by BLT1, while the inactivation of LTB4 is promoted by PPARalpha. PATIENTS AND METHODS: BLT1 and PPARalpha proteins were quantified by immunohistochemistry in specimens obtained during lung surgery from 19 smokers with or without COPD and from 7 nonsmoking subjects. RESULTS: We have shown that the percentages of PPARalpha-positive alveolar macrophages and PPARalpha-positive cells in the alveolar wall were increased in COPD patients compared with control subjects. Moreover, the patients with COPD exhibited a significant increase of BLT1-positive alveolar macrophages compared with nonsmokers and an increased number of BLT1-positive cells in the alveolar walls compared with non-COPD smokers. In contrast, BLT1 and PPARalpha immunoreactivity did not differ significantly between nonsmokers and non-COPD smokers. Most of BLT1-positive cells in the alveolar walls were neutrophils and CD8 cells. While the number of neutrophils infiltrating the lung parenchyma was similar among the three groups, the number of CD8 T cells was increased in COPD patients, but there was no evidence that BLT1 was up-regulated specifically on these cells in COPD patients. CONCLUSION: The results demonstrated that BLT1 and PPARalpha are detectable in alveolar macrophages and CD8 T cells in human lung tissue, and suggest that the dual LTB4 receptor system is up-regulated in the peripheral lungs of smokers who are susceptible to the development of COPD. This system might represent a novel target for therapeutic intervention in COPD patients.

Aged↗

Occupational asthma.

Substantial epidemiologic and clinical evidence indicates that agents inhaled at work can induce asthma. In industrialized countries, occupational factors have been implicated in 9 to 15% of all cases of adult asthma. Work-related asthma includes (1) immunologic occupational asthma (OA), characterized by a latency period before the onset of symptoms; (2) nonimmunologic OA, which occurs after single or multiple exposures to high concentrations of irritant materials; (3) work-aggravated asthma, which is preexisting or concurrent asthma exacerbated by workplace exposures; and (4) variant syndromes. Assessment of the work environment has improved, making it possible to measure concentrations of several high- and low-molecular-weight agents in the workplace. The identification of host factors, polymorphisms, and candidate genes associated with OA is in progress and may improve our understanding of mechanisms involved in OA. A reliable diagnosis of OA should be confirmed by objective testing early after its onset. Removal of the worker from exposure to the causal agent and treatment with inhaled glucocorticoids lead to a better outcome. Finally, strategies for preventing OA should be implemented and their cost-effectiveness examined.

Adult↗

Defective production of soluble HLA-G molecules by peripheral blood monocytes in patients with asthma.

BACKGROUND: HLA-G, a human nonclassic MHC class I molecule, is responsible for complex immunoinhibitory functions. HLA-G is expressed as membrane-bound and is secreted as soluble molecules by the peripheral blood CD14+ monocytes activated by IL-10. OBJECTIVE: It has been reported that LPS stimulation induces IL-10 production by PBMCs and that IL-10 levels are reduced in patients with severe asthma compared with patients with mild asthma and healthy subjects. The study was designed to investigate whether this impaired IL-10 production can affect the expression and the secretion of soluble HLA-G (sHLA-G)-1/HLA-G5 molecules. METHODS: We investigated the production of sHLA-G1/HLA-G5 and IL-10 by specific ELISAs in the culture supernatants of LPS-activated PBMCs from 24 healthy subjects and 20 patients with moderate to severe persistent asthma. RESULTS: LPS stimulation induced the secretion of IL-10 and sHLA-G1/HLA-G5 molecules in all healthy subjects, whereas in patients with asthma, the levels of IL-10 were significantly lower (P < .001) and the number of cultures exhibiting detectable sHLA-G1/HLA-G5 was reduced (7/20; P < .001). The addition of exogenous IL-10 to LPS-stimulated PBMCs from patients with asthma restored normal sHLA-G1/HLA-G5 production. CONCLUSION: Our data suggest that a specific deficit of IL-10 secretion in patients with asthma could prevent the normal production of sHLA-G1/HLA-G5 molecules. The reduction of immunosuppressive activity mediated by HLA-G could in turn contribute to the persistence of chronic airway inflammation in asthma.

Adult↗

Effect of inhalation of thermal water on airway inflammation in chronic obstructive pulmonary disease.

Thermal water inhalations have been traditionally used in the treatment of upper and lower chronic airway diseases. However, the benefit and the mechanism of this treatment have not been properly assessed. To determine whether inhaled salt-bromide-iodine thermal water improves lung function, quality of life and airway inflammation, 39 patients with chronic obstructive pulmonary disease (COPD) were randomly assigned to receive 2-weeks inhalation treatment with thermal water (active, no. = 20) or normal saline (control, no. = 19) in single blind. Lung volumes were measured, Saint George's respiratory questionnaire (SGRQ) was administered and induced sputum was performed before and after treatment. No changes in pre- and post-salbutamol lung volumes was observed after inhalation treatment in both groups. SGRQ score showed a significant improvement in active group compared with control group at the end of the trial. The concentration of total cells in induced sputum increased significantly in both active (P < 0.05) and control groups (P < 0.05). Inhalation of thermal water induced a small but significant decrease in percentages of sputum neutrophils (P < 0.01) and a parallel increase in macrophages (P < 0.01). In contrast, normal saline inhalation was not associated with changes in differential sputum cell counts. In conclusion, treatment with inhaled salt-bromide-iodine thermal water in COPD is associated with a reduced proportion of neutrophils in induced sputum suggesting that thermal water may have a mild anti-inflammatory effect on the airways. However, the short-term improvement in some components health-related quality of life was not related with changes in lung function or with the degree of airway inflammation.

Administration, Inhalation↗

Effect of specific immunotherapy added to pharmacologic treatment and allergen avoidance in asthmatic patients allergic to house dust mite.

BACKGROUND: Although several studies support the efficacy of specific immunotherapy in allergic asthma, its benefit compared with that of standardized pharmacologic intervention remains unknown. OBJECTIVE: A double-blind, placebo-controlled trial in 72 patients with mild-to-moderate asthma and allergy to house dust mite (HDM; Dermatophagoides species) was conducted to assess the effects of specific immunotherapy added to guideline-adjusted pharmacologic treatment and allergen avoidance. METHODS: After 1 observational year of pharmacologic treatment and standard measures of HDM avoidance, 2 groups of asthmatic subjects were randomly assigned to receive specific immunotherapy consisting of subcutaneous injections of either a mixture of Dermatophagoides pteronyssinus and Dermatophagoides farinae vaccine (n=41) or placebo (n=31) for 3 years. Medications were adjusted every 3 months according to the Global Initiative for Asthma guidelines. RESULTS: The adjustment of treatment was associated with a reduction in asthma symptom scores in all subjects. The addition of specific immunotherapy was associated with a decrease in the number of subjects requiring rescue bronchodilators, an increase in morning and evening peak expiratory flow, and a reduced skin sensitivity to HDM extracts. The addition of specific immunotherapy had no significant effects on the cumulative dose of inhaled corticosteroids, asthma symptoms, lung volumes, or bronchial responsiveness to methacholine. CONCLUSION: These results suggest that specific immunotherapy added to pharmacologic treatment and HDM avoidance provides marginal but statistically significant clinical benefits, possibly by reducing the allergic response of asthmatic patients sensitized to HDM.

Administration, Inhalation↗

Airway inflammation in childhood asthma.

Airway pathology has been extensively investigated in adulthood asthma, whereas only few studies examined bronchial biopsies in childhood asthma. To evaluate the airway pathology in children with asthma, we analyzed bronchial biopsies obtained from 23 children undergoing bronchoscopy for clinical indications other than asthma. Nine had mild/moderate asthma. Six had atopy without asthma, and eight had no atopy or asthma. We measured basement membrane thickness and quantified the number of eosinophils, mast cells, neutrophils, macrophages, T lymphocytes, and positive cells for transforming growth factor-beta1 (TGF-beta1) and its receptors I and II (TGFbeta-RI and TGFbeta-RII) in subepithelium. Children with asthma had an increase in basement membrane thickness and in the number of eosinophils compared with control subjects, but not compared with children with atopy. They also had a decreased expression of TGFbeta-RII compared with both those with atopy and control subjects. In children with asthma, the number of eosinophils correlated negatively with TGFbeta-RII and positively with symptom duration. In conclusion, airway eosinophilia and basement membrane thickening, which are the pathologic features that are characteristic of adulthood asthma, are already present in children with mild asthma, and even in children with atopy without asthma. Moreover, in children with asthma but not in children with atopy without asthma, there is a downregulation of TGFbeta-RII.

Adolescent↗

[Pathophysiology of chronic obstructive pulmonary disease].

Chronic obstructive pulmonary disease (COPD) is a disease state characterised by airflow obstruction that is not fully reversible and progressive. Symptoms, as cough, sputum production and dyspnoea, functional impairment and complications of COPD can all be explained on the basis of the underlying lung inflammation and the resulting pathology. The chronic airflow obstruction is caused by a mixture of small airway disease (obstructive bronchiolitis) and parenchymal destruction (emphysema). On one hand, chronic inflammation causes remodelling and narrowing of the small airways. On the other hand, destruction of the lung parenchyma, also by an inflammatory process, leads to the loss of alveolar attachments to the small airways and decreases lung elastic recoil. In turn, these changes reduce the ability of the airways to remain open during expiration.

Airway Obstruction↗

Airway inflammation in severe chronic obstructive pulmonary disease: relationship with lung function and radiologic emphysema.

The lung pathology of severe chronic obstructive pulmonary disease (COPD) has been poorly investigated. We examined surgical specimens obtained from patients with severe (forced expiratory volume in 1 second [FEV(1)] = 29 +/- 3% predicted, n = 9) or mild/no airflow limitation (FEV(1) = 86 +/- 5% predicted, n = 9) and similar smoking history. With histochemical and immunohistochemical methods we quantified the structural changes and the inflammatory cells in small airways and in muscular pulmonary arteries. As compared with smokers with mild/no COPD, smokers with severe COPD had an increased number of leukocytes in the small airways, which showed a positive correlation with the radiologic score of emphysema and with the value of residual volume, and a negative correlation with the values of FEV(1) and carbon monoxide diffusing capacity. The inflammatory process was characterized by an increase in CD8(+) and CD4(+) T-lymphocytes in the airway wall and by an increase in macrophages in the airway epithelium. When all smokers were considered together, the smoking history was correlated with both the airway wall and smooth muscle thickness, suggesting that smoking itself may play a role in the development of structural changes. No structural and cellular differences were observed in pulmonary arteries between smokers with severe COPD and smokers with mild/no COPD. In conclusion, in the small airways of smokers with severe COPD, there is an increased number of leukocytes, which is correlated with reduced expiratory flow, lung hyperinflation, carbon monoxide diffusion impairment, and radiologic emphysema, suggesting a role for this inflammatory response in the clinical progression of the disease.

Case-Control Studies↗