Search PubMed⌕ Search

Biomedical subjects

D Olivieri

Publications and source records attributed to D Olivieri.

At least 37 records · Page 2Linked to original sources

Quality control of spirometry in the elderly. The SA.R.A. study. SAlute Respiration nell'Anziano = Respiratory Health in the Elderly.

We evaluated the outcome of the spirometry quality control program of the SA.R.A. multicenter project, the aim of which is the multidimensional assessment of asthma and COPD in the elderly (>/= 65 yr). The factors determining this quality were also evaluated. The program was based on standardized procedures (ATS recommendations), performed by specifically trained and certified personnel; a fully-computerized spirometer with customized software was used for spirometry. A reference center made monthly controls. Overall, 638 cases and 984 controls were examined. Spirometric measurements were obtained in 607 cases and 912 controls; 508 and 747 tests with at least three acceptable curves were obtained in cases and in controls, respectively (NS). The percentage of reproducible tests ranged between 95.8% for FEV(1) in controls and 87.6% for FVC in cases. The average reproducibility for FEV(1) was 61.6 ml in cases and 58.3 ml in controls (NS). Cognitive impairment, shorter 6-min walk distance, and lower educational level were found to be independent risk factors for a poorer acceptability rate (logistic regression analysis). Male sex and age were risk factors for a poorer reproducibility of FEV(1). Reproducibility tended to improve with time (p < 0.001). Although spirometry becomes increasingly difficult in aging patients, a rigorous quality control program can ensure that reliable data are obtained in the majority of patients.

Age Factors↗

The effect of inflammation on mucociliary clearance in asthma: an overview.

Mucociliary clearance (MCC) is one of the most important nonspecific defense mechanisms of the respiratory tract, and its impairment is a well-documented feature of chronic respiratory diseases, including asthma. In vitro and in vivo data suggest that several inflammatory mediators influence the mucociliary apparatus. Epithelial damage and functional abnormalities have been described in bronchial asthma, along with changes in mucus-secreting cells and the chemical and rheological properties of airway fluid. Although the mechanisms of MCC impairment in asthma are not clearly understood, data in the recent literature suggest that airway inflammation plays a major role. In this article, we review studies on MCC alterations in light of up-to-date findings on pathogenetic mechanisms in asthma.

Animals↗

Taking on the student role: how can we improve the experience of registered nurses returning to study?

Regardless of the number of nurses who undertake graduate certificate courses in critical care nursing in Victoria, Australia, there is still a shortage of skilled nurses in the critical care areas. Preparation for practice in this specialist field has moved from hospital-based programs to tertiary-based courses during the past decade. As a consequence, there has been scrutiny of the clinical ability of graduates to perform the role function. Although this is understandable, anecdotal evidence to date indicates that students in these courses experience many difficulties, yet very little is written about the stressors they encounter. As the future of the critical care work force depends on a constant supply of students undertaking courses, it is essential to gain insight into the student experience, with a view to optimising it for future students and perhaps preventing attrition from courses. This paper describes a qualitative research study involving 14 students undertaking a graduate certificate course in critical care nursing. The aim of the study was to document the students' experience in relation to factors they identified as helping or hindering their progress on the course. Data were obtained at three points during the academic component of the course: on entry, at the end of semester 1 and at the end of semester 2. Interviews and questionnaires were used as the data collection methods. Results indicate that for this group of students, the experience of undertaking the course was adversely affected by stress related to three factors: change of role from clinician back to student; unmet expectations, and exhaustion. Recommendations related to preparation for study, curriculum timelines and peer support are included in this paper.

Attitude of Health Personnel↗

Induced sputum in patients with newly diagnosed sarcoidosis: comparison with bronchial wash and BAL.

OBJECTIVES: Sarcoidosis is characterized by a diffuse alveolar inflammatory process, although bronchial airways are often involved. This study compares the cellular profiles of induced sputum (IS), bronchial washing (BW), and BAL in newly diagnosed sarcoidosis patients to those in control subjects, and examines whether inflammatory cell counts from IS are correlated with inflammatory cell counts from BW and BAL in sarcoidosis patients. PATIENTS AND MEASUREMENTS: We recruited 15 untreated patients with stage I and II pulmonary sarcoidosis and 12 healthy volunteers. Sputum was induced with hypertonic saline solution in all individuals. Bronchoscopy was performed on a different occasion in all patients and in five control subjects. RESULTS: Mean lymphocyte counts in IS, BW, and BAL fluid from sarcoidosis patients were significantly higher than in control subjects (9.4% vs 3.8%, p < 0.05; 12.6% vs 3.9%, p < 0.05; 24.1% vs 2.6%, p < 0.05, respectively). Moreover, total cell count and percentage of epithelial cells in IS were significantly higher in sarcoidosis patients than in control subjects (p < 0.01 and p < 0.05, respectively). In sarcoidosis patients, comparison between different samples showed significantly higher percentages of macrophages in BW and BAL than in IS (p < 0.05 and p < 0.01, respectively), whereas the percentage of neutrophils was higher in IS compared with BW and BAL (p < 0.01 and p < 0.001, respectively). Finally, the percentage of lymphocytes in IS was significantly lower than that in BAL (p < 0.05) but not that in BW. CONCLUSIONS: We demonstrated that, compared with IS in healthy control subjects, IS in untreated pulmonary sarcoidosis patients contains more total cells, lymphocytes, and epithelial cells. Although the relative proportion of inflammatory cells in the three samples differed, lymphocyte counts in IS were high. This finding suggests that IS could be used as a valuable alternative to more conventional invasive techniques in clinical assessment of pulmonary sarcoidosis patients.

Administration, Inhalation↗

Effect of sputum induction on spirometric measurements and arterial oxygen saturation in asthmatic patients, smokers, and healthy subjects.

BACKGROUND: Sputum production induced by inhalation of hypertonic saline solution has been proposed as a technique to collect secretions and inflammatory cells from the airways of subjects with bronchial asthma or with a history of smoking. The aim of this study was to determine the effect of a sputum induction procedure on spirometric results and arterial oxygen saturation (SaO(2)) in asthmatic patients, smokers, and healthy subjects. METHODS: We recruited 14 subjects suffering from asthma (11 men and 3 women; age range, 18 to 49 years), 14 subjects with a history of smoking (5 men and 9 women; age range, 23 to 64 years), and 9 healthy volunteers (7 men and 2 women; age range, 28 to 54 years). To obtain a sample of induced sputum, all subjects inhaled a mist of 3% hypertonic saline solution nebulized for 5 min and repeated the cycle no more than four times. Asthmatic patients were pretreated with 200 microg salbutamol (inhaled). During sputum induction, the transcutaneous SaO(2) was continuously measured and baseline, fall, and the differences between baseline and fall SaO(2) were recorded. Additionally, we measured the duration of mild desaturation (change in SaO(2), < 4%) and of marked desaturation (change in SaO(2), > 5%) in each subject. Finally, baseline FEV(1) and changes in FEV(1) as a percentage of baseline values were recorded in all subjects. RESULTS: We found that baseline and fall SaO(2) values for the three groups were similar. However, in each group a significant mean change in SaO(2) was evident during sputum production (asthmatic patients, 6.0%; smokers, 5.3%; healthy subjects, 6.0%). Moreover, the mean durations of mild desaturation were 7 min, 21 s in asthma patients; 8 min, 24 s in smokers; and 7 min, 16 s in healthy subjects. Similarly, the durations of marked desaturation were 1 min, 25 s in asthmatic patients, 1 min, 19 s in smokers, and 1 min, 21 s in healthy subjects. The mean (+/- SD) fall in FEV(1) was not statistically different among the three groups (asthmatic patients, 1.36 +/- 5.6%; smokers, 7.58 +/- 11.76%; and healthy subjects, 0.05 +/- 9.6%). However, one smoker did experience excessive bronchoconstriction (fall in FEV(1), > 20%). CONCLUSIONS: This study demonstrated a significant and comparable fall in SaO(2) during sputum induction by inhalation of hypertonic saline solution in asthmatic patients, smokers, and healthy subjects. The results suggest that subjects who are hypoxemic before sputum induction require SaO(2) monitoring during the procedure.

Adolescent↗

Heat shock protein 70 upregulation is related to HLA-DR expression in bronchial asthma. Effects of inhaled glucocorticoids.

BACKGROUND AND OBJECTIVE: Antigen processing determines the production of peptides from antigens - including allergens - and their binding to class II major histocompatibility complex molecules, that stimulate T-cell responses. Heat shock protein (hsp) 70 are recognized to have a role in chaperoning antigenic peptides and in facilitating class II peptide assembly. We studied the HLA-DR and hsp70 expression on BAL cells and bronchial biopsies from asthmatics, as well as the effect of low dose fluticasone propionate treatment. METHODS: Twenty-three asthmatics and eight normal subjects were selected. In each subject BAL and bronchial biopsies were performed. Eighteen out of 23 asthmatics, underwent the second bronchoscopy after 6 weeks of low dose inhaled fluticasone propionate treatment (250 microg b.d.) in a placebo-controlled double-blind study. BAL fluid and biopsies were processed to evaluate HLA-DR and hsp70 expression by immunochemistry methods. RESULTS: Hsp70 and HLA-DR upregulation was present on professional and non-professional antigen presenting cells (APCs). In asthmatics, the hsp70 and HLA-DR expression was higher in BAL (hsp70 P<0.001, HLA-DR P<0.001) and bronchial epithelium (hsp70 P<0.001, HLA-DR P<0.001) when compared with controls. We also observed a significant correlation between hsp70 and HLA-DR expression in BAL (P<0.005) and epithelium (P<0.001). Fluticasone propionate treatment down-regulated the hsp70 and HLA-DR expression in BAL (hsp70 P < 0.001, HLA-DR P < 0.05) and bronchial epithelium (hsp70 P < 0.05, HLA-DR P < 0.05). A serial section comparison study showed that CD1a+ cells and macrophages were positive for both hsp70 and HLA-DR in the submucosa. CONCLUSIONS: Our results support the hypothesis that hsp70 over-expression implies a potential role for these proteins in antigen processing and/or presentation resulting in an increased activity of APCs, which is essential for the initiation and modulation of the asthmatic immune response in chronic asthma. Fluticasone propionate induces downregulation of HLA-DR and hsp70 molecules thus regulating inflammation by affecting key mechanisms of the allergic response.

Administration, Inhalation↗

Personality profiles and breathlessness perception in outpatients with different gradings of asthma.

We studied the relationship between personality profiles, breathlessness perception and clinical and functional features in 36 outpatient asthmatics (12 females; age range: 18-52 yr). Each patient underwent psychometric evaluation with Minnesota Multiphasic Personality Inventory (MMPI). Breathlessness perception was evaluated by Borg's scale during methacholine (M) challenge, and PS20 (the perception score obtained when FEV1 fell by 20%) was recorded. Baseline FEV1 values ranged from 70.0 to 126%. PC20 M values ranged from 0.05 to 31.7 mg/ml. According to a symptoms score system (0 to 12 points), 12 asthmatics were classified as mild, 12 as moderate, and 12 as moderate/severe. We did not find any specific personality profile in asthmatic patients. Sixteen asthmatics had at least one MMPI subscale score indicative of psychological disturbances. We found a significant trend from mild to moderate and moderate/severe asthmatics (p < 0.015), when the number of asthmatics with subscale scores indicative of psychological disturbances was compared to that of asthmatics with normal scores. Moreover, we found that the asthmatics with scores indicative of hypochondriasis showed a significant trend from mild to moderate and moderate/severe asthma (p < 0.015). Furthermore, in all asthmatic patients, hypochondriasis scores were positively correlated to asthma severity score (p < 0.02). PS20 values ranged from 0.1 to 8.1. Twelve asthmatics were hypoperceivers (PS20 < or = 1) and four were hyperperceivers (PS20 > or = 5). We observed a significant trend from mild to moderate and moderate/severe asthmatics (p < 0.025) when we compared the number of hypoperceivers to that of normoperceivers. In conclusion, we found that in outpatients with different grading of asthma, severity of disease is linked to psychological disturbances and poor perception of breathlessness, additionally, hypochondriasis was related to disease severity in all patients.

Adolescent↗

Mucoactive drugs in the management of chronic obstructive pulmonary disease.

In chronic obstructive pulmonary disease (COPD), mucus hypersecretion is considered one of the main symptoms. Recently the natural history of COPD has been better defined and chronic mucus hypersecretion is now viewed as linked to the acceleration of forced expiratory volume in one second (FEV1) decline and not merely as an "innocent disorder". In the past, mucoactive drugs were claimed to treat mucus hypersecretion. However, since most mucoactive drugs have not been evaluated in large clinical studies, European Respiratory Society and American Thoracic Society COPD guidelines discourage their use for treatment of COPD patients. Clinical trials have been often disappointing because improvement in lung function has been adopted as the main outcome, despite bronchial obstruction in COPD patients being frequently irreversible or poorly reversible. Thus, goals for treatment in COPD patients should include not only improvement in lung function, but also clinical symptoms and quality of life. Moreover, to rightly allocate these drugs in COPD management and to try to modify the natural history and progression of COPD, mucus hypersecretion might require treatment in the first stage of the disease. In conclusion, mucoactive treatments for chronic obstructive pulmonary disease patients should be re-evaluated in the future in patients selected according to demographic factors such as degree and reversibility of bronchial obstruction due to mucus hypersecretion, patient smoking habits and other socioeconomic parameters which have proved to be relevant to the progression of the disease, according to the latest recommendations for guidelines on clinical trials of mucoactive drugs in chronic bronchitis and chronic obstructive pulmonary disease.

Animals↗

Eosinophils, mast cells, and basophils in induced sputum from patients with seasonal allergic rhinitis and perennial asthma: relationship to methacholine responsiveness.

OBJECTIVES: We attempted to determine whether inflammation is present in induced sputum of patients with seasonal allergic rhinitis (AR) as compared with those with perennial asthma (AS) and examined its relationship with bronchial responsiveness to methacholine. METHODS: Sputum was induced in 30 patients with seasonal rhinitis in response to grass pollens only and in 15 patients with stable, asymptomatic asthma. The AR group was divided according to methacholine PD20 value: the AR- group (n = 15) had a methacholine PD20 greater than 24 micromol; the AR+ group (n = 15) had a methacholine PD20 ranging between 2.2 and 19.6 micromol. In the AS group, methacholine PD20 ranged between 0.42 and 2.6 micromol. The percentage of eosinophils and metachromatic cells (alcian blue-positive) was assessed in sputum by light microscopy. Tryptase-positive cells and EG2+ cells were identified by immunocytochemistry with the mouse anti-human mast cell-tryptase monoclonal antibody and the monoclonal anti-eosinophil cationic protein antibody. RESULTS: We found that the number of eosinophils in the AS group was greater than that in the AR+ group (p < 0.05) and in the AR- group (p < 0.01). Moreover, the eosinophil count was lower in the AR- group compared with the AR+ group (p < 0.05). Similarly, the number of EG2+ cells was greater in the AS group than in the AR group (p < 0.02) and the AR- group (p < 0.05). Moreover, the EG2+ cell count was lower in the AR- group than in the AR+ group (p < 0.05). The number of mast cells and basophils in the AS group was greater than that in the AR group (p < 0.05 and p < 0.01, respectively). Mast cells in sputum were tryptase-positive. Basophils were present in sputum from 23% of patients with AR and 53% of patients with asthma. There was a significant correlation between methacholine PD20 and eosinophils (p < 0.005) and mast cells (p < 0.02) but not with basophils in those patients showing a measurable methacholine PD20 (AR+ and AS groups). CONCLUSIONS: Inflammatory cells are present not only in the airways of patients with asthma but also in airways of patients with seasonal AR, even outside natural exposure. Moreover, we provide evidence for the presence of basophils in sputum of patients with asthma even during clinical remission. The presence of bronchial responsiveness is associated with an increase in the number of eosinophils and metachromatic cells. Our findings are consistent with the hypothesis that eosinophils, as well as mast cells, contribute to bronchial responsiveness not only in AS but also in seasonal AR.

Adult↗

Effect of short-term treatment with low-dose inhaled fluticasone propionate on airway inflammation and remodeling in mild asthma: a placebo-controlled study.

In a double-blind, parallel-group study, we examined the effect of short-term treatment with inhaled fluticasone propionate (FP) in a group of 20 nonsmoking asthmatic patients who required only beta2-agonists to control their symptoms. We administered FP (250 microg twice daily) or matched placebo for 6 wk. Methacholine challenge was performed before treatment, after 3 wk, and at the end of treatment. Each patient underwent bronchoscopy with bronchoalveolar lavage (BAL) and bronchial biopsy before and after treatment. Eight patients in the placebo group and nine patients in the FP group completed the study. Bronchial responsiveness to methacholine decreased significantly only after 6 wk of treatment with FP (p < 0.05). When we compared the FP group with the placebo group, we observed a significant decrease only in the number of cells expressing intracellular adhesion molecule-1 (ICAM-1) and MAC-1 (p < 0.04 and p < 0.03, respectively). Moreover, we saw that the tryptase level in BAL decreased (p < 0.001), whereas the eosinophil cationic protein (ECP) level did not change significantly. Additionally, the number of eosinophils and mast cells in the lamina propria in bronchial biopsies specimens was significantly smaller in the FP group than in the placebo group (p < 0.02 and p < 0.01, respectively). Additionally, in the FP group, we found that basement-membrane thickness was significantly decreased when compared with that of the placebo group (p < 0.05). In conclusion, our results show that short-term treatment with low-dose FP reduces inflammatory cell infiltration into the lamina propria in bronchial biopsy specimens. Moreover, short-term low-dose FP treatment might control the intensity of airway remodeling in mild asthma.

Administration, Inhalation↗

Airways remodeling is a distinctive feature of asthma and is related to severity of disease.

PURPOSE: Airways remodeling, evaluated as the subepithelial layer thickness, was compared in asthmatic patients with that of healthy subjects, and was related to clinical grading of disease, presence of atopy, and length of asthmatic history. SUBJECTS AND METHODS: Thirty-four patients with stable asthma (mean age+/-SD: 26.5+/-9.2 years; 10 female) treated with only inhaled beta2-agonists and eight healthy volunteers (mean age+/-SD: 24.6+/-2.5 years; four female) were recruited for the study. Twenty-seven of 34 asthmatics had atopy. Eleven patients had newly diagnosed conditions (duration of disease < or = 1 year), nine patients had long asthmatic history (> 1 year and < or = 10 years), and 14 had prolonged asthmatic history (> 10 years). Bronchial responsiveness to methacholine (M) was expressed as provocative concentration of M causing a 20% fall in FEV1 (PC20) (mg/mL). Degree of asthma severity was assessed using a 0- to 12-point score based on symptoms, bronchodilator use, and daily peak expiratory flow variability over a 3-week period. Bronchoscopy and bronchial biopsy were performed successfully for all subjects; the subepithelial layer thickness, in biopsy samples, was measured from the base of bronchial epithelium to the outer limit of reticular lamina. RESULTS: In asthmatics, baseline FEV1 values (percent of predicted) ranged from 75.7 to 137.0%, and PC20 M ranged from 0.15 to 14.4 mg/mL. According to the asthma severity score, 14 asthmatics were classified as having mild disease, 14 as having moderate disease, and six as having severe disease. The mean values of subepithelial layer thickness were 12.4+/-3.3 microm (range, 6.8 to 22.1 microm) in asthmatics, and 4.4+/-0.5 microm (range, 3.8 to 5.2 microm) in healthy subjects (p<0.001). Subepithelial layer thickness of those with severe asthma differed significantly from that of patients with moderate and mild asthma (16.7+/-3.1 microm vs 12.1+/-2.7 microm and 10.8+/-2.4 microm, p<0.01 and p<0.003, respectively). Moreover, in asthmatics, degree of thickening was positively correlated to asthma severity score (Spearman rank correlation coefficient [rs]=0.581; p<0.001), and negatively correlated with baseline FEV1 (rs=-0.553; p<0.001) and PC20 M (rs=-0.510; p<0.01). No difference was found between degree of thickening observed in atopic asthmatics, compared with that of nonatopic asthmatics, or between degree of thickening in patients with different lengths of asthmatic history. Lastly, multiple regression analysis revealed that asthma severity score was the significant predictive factor for thickness of subepithelial layer. CONCLUSIONS: We confirmed that airways remodeling is a very distinctive and characteristic pathologic finding of asthma. We also demonstrated that it is related to the clinical and functional severity of asthma, but not to atopy or length of asthmatic history.

Adolescent↗

Lung epithelial permeability and bronchial responsiveness in subjects with stable asthma.

Lung epithelial permeability of asthmatic patients has been reported to be similar or lower than that of healthy subjects and to be correlated or not to bronchial hyperresponsiveness. To clarify these discrepancies, we evaluated 99mTc-DTPA pulmonary clearance in a group of carefully selected asthmatic patients with mild, stable asthma (n = 13; seven women; mean age +/- SD = 27.69 +/- 6.63 years), and compared them with a group of healthy, nonsmoking subjects (n = 8; six women; mean age +/- SD = 24.38 +/- 5.15 years). Selection criteria for asthmatics were as follows: baseline FEV1 > or = 80% of predicted values, no bronchial infections, and/or no asthma attacks during 4 weeks prior to study and peak expiratory flow rate variability lower than 20%, over a period of 3 weeks. Patients controlled symptoms with beta 2-adrenergic drugs only, regularly or on demand. Mean baseline FEV1 (+/-SD) as percent of predicted was 102.38 +/- 13.97 and 112.88 +/- 18.36, respectively (p < 0.05). In the asthmatic group, bronchial responsiveness to methacholine (PC20 M FEV1) ranged between 0.55 and 28.5 mg/mL. Mean value (+/-SD) of DTPA clearance from lungs to blood (evaluated on the first 10 min out of 30 min of the curves) in the asthmatic group was not different from that of control group (68.31 +/- 21.46 and 69.5 +/- 15.73). In the asthmatic patients, there was no correlation between PC20 M values and DTPA T1/2 min of the whole lung, nor between PC20 M and inner and outer lung clearance zones. Moreover, both in asthmatics and healthy subjects, DTPA clearance of outer (alveolar) zones was significantly faster than that of inner (bronchial) zones (57.69 +/- 19.94 vs 102.08 +/- 38.19, p < 0.001, and 59.75 +/- 12.49 vs 103.5 +/- 31.86, p < 0.003, respectively). Our data show that DTPA clearance in patients with stable asthma is similar to that found in healthy subjects; it is not correlated to degree of bronchial responsiveness and occurs more rapidly in the outer zones than in the inner zones, both in asthmatic patients and in healthy subjects. Thus, to date, DTPA clearance index is not a valid tool for identifying and/or monitoring asthmatic patients.

Adolescent↗

Does the mast cell still have a key role in asthma?

In recent years, the emerging concept of bronchial inflammation as a prominent histopathologic characteristic of asthma has profoundly modified the view of the role of the mast cell, which was traditionally thought to be linked to the release of soluble chemical mediators substantially involved in the genesis of acute, immediate bronchospasm. The finding that the production of proinflammatory cytokines by mast cells in asthmatic airways is comparable, in some circumstances, to that of T-cell origin, has led to the hypothesis that mast cells, along with T lymphocytes and eosinophils, may also contribute to the genesis of chronic, persistent asthma. This hypothesis is further supported by the finding that mast cells are able to functionally interact with B cells (promoting IgE synthesis) and T lymphocytes (acting as antigen presenting cells), thus taking part in the immune network. Moreover, mast cells produce an exclusive family of proteases (tryptases and chymases) that exert many biological actions relevant to airways inflammation and remodeling. Future studies will better explain the role of mast cells in asthma and, more specifically, the links with bone marrow-where mast cell progenitors originate-and the airways, where mast cells develop, differentiate, and assume the functions of mature cells. This article reviews recent data available on these topics.

Asthma↗

Bronchial responsiveness to distilled water and methacholine and its relationship to inflammation and remodeling of the airways in asthma.

Although bronchial hyperresponsiveness in asthma is associated with inflammation within the airways, it is not known whether the degree and type of inflammation influence the response to different stimuli and whether pathologic changes of airway structure influence the bronchoconstrictive responses. Therefore, number of inflammatory cells in the epithelium and the lamina propria and the basement membrane thickness were estimated from bronchial biopsies taken in 27 asthmatic subjects (range percent predicted FEV1: 75.6 to 132.1, range of daily PEF variability: 1.9% to 20%) and related to the degree of bronchial responsiveness to ultrasonically nebulized distilled water (UNDW) and methacholine (M). PD20UNDW (provocative dose) was measurable in 15 of 27 patients and ranged between 1.01 and 20.4 ml. PC20M (provocative concentration) ranged between 0.15 and 31.7 mg/ml. In the 15 responders to UNDW, total inflammatory cells (p<0.04) and eosinophils (p<0.015) within the epithelium were higher than in 12 nonresponders to UNDW (PD20 > 34.8 ml). There was no correlation between PD20UNDW and any cell counts whereas negative correlations were found between PC20M and both total inflammatory cells (rs = -0.57; p<0.005) and eosinophils (rs = -0.63; p< 0.0015) within the epithelium. The degree of thickening of subepithelial layer ranged between 7 and 16 micrometers+ (n=26). Thickness correlates both with total inflammatory cells (rs = 0.49; p<0.025) and eosinophils (rs = 0.61; p< 0.003) within the epithelium. Moreover, it was correlated with baseline FEV1 (rs = -0.57; p<0.003) and daily peak expiratory flow (PEF) variability (rs = 0.51; p<0.01). A weak but significant correlation was also found between subepithelial layer thickness and PC20M (rs = -0.42; p<0.04). The results of this study demonstrate that eosinophilic inflammation of bronchial epithelium plays a role in determining UNDW and M responsiveness in asthma. Moreover, they suggest that remodeling of the airways such as thickening of subepithelial layer correlates with indices of asthma severity and could contribute to the degree of M but not to UNDW responsiveness.

Adolescent↗