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Biomedical subjects

V Bellia

Publications and source records attributed to V Bellia.

At least 37 records · Page 2Linked to original sources
PubMed2000

Spontaneous gastroesophageal reflux and airway patency during the night in adult asthmatics.

Controversies still exist on the role of nighttime gastroesophageal reflux (GER) in precipitating nocturnal asthma. We tested the relationship between GER and nocturnal bronchoconstriction by continuously and simultaneously monitoring both respiratory resistances and esophageal pH in seven asthmatics with moderate to severe GER disease. Twenty-nine GER episodes were found during the study night lasting more than 5 min (LGER) and 72 not longer than 5 min (SGER). Both long (LGER) and short (SGER) gastroesophageal refluxes were able to maintain significantly higher lower respiratory resistances (RLR) at the resolution of each GER episode (RLR(e)) with respect to baseline values. RLR, expressed as the area under the RLR curve along each GER episode (AUCR(LR)) and as RLR(e), showed significant correlations with GER duration. Moreover, a significant correlation was found between RLR measured 10 min after GER resolution and GER duration during each episode. We conclude that GER itself is able to elicit nocturnal bronchoconstriction in asthmatics with moderate to severe GER disease and that bronchoconstriction severity and duration are related to GER duration.

Adult↗
PubMed2000

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↗
PubMed2000

Prevalence of nocturnal asthma in a general population sample: determinants and effect of aging.

Nocturnal asthma (NA) is important because of clinical and prognostic implications. Previous data on prevalence may be overestimated, because they are derived from selected series. Observations on monitoring of peak expiratory flow in elderly asthmatics suggested that prevalence of NA may increase with age. This study was designed to estimate the prevalence of NA-related symptoms in a sample drawn from a general population and evaluate the role of aging. Subjects (1,100, mean age 41.9, SD 22.8 years) were randomly selected from the lists of seven general practitioners. A questionnaire on nighttime and morning NA-associated symptoms was used and frequency of occurrence was rated as never, sometimes (less than once a week), and often (once a week or more). In the overall sample, symptoms were experienced "sometimes" by 2.3%-4.9% of subjects, whereas the response "often" was given by 0.9%-1.6% of subjects. Among subjects with a diagnosis of asthma, symptoms occurred sometimes in 16.7%-23.7% and often in 5%-15%. Symptoms reported the morning after were significantly more frequent among patients aged 65 years and older (p < 0.005), whereas the difference for nighttime symptoms was not statistically significant in different age groups, confirming an age-related blunted sensitivity. Logistic regression analysis shows that a diagnosis of asthma is the most important correlate of symptoms, with odds ratio (OR) up to 14.78 for cough; advanced age also proved to be an independent risk factor (OR 3.35-4.97). In conclusion, although the prevalence of NA was previously overestimated, our results indicate its importance, particularly among elderly patients who are exposed to a prominent risk of underdiagnosis and undertreatment.

Adult↗
PubMed1998

HCV genotypes in Northern Italy: a survey of 1368 histologically proven chronic hepatitis C patients.

BACKGROUND/AIMS: Hepatitis C virus (HCV) easily undergoes genomic changes, thus accounting for the presence of different genotypes, with different geographic distributions and different outcomes of chronic hepatitis. Type 1b is frequently found in advanced diseases; however, since this genotype is the most prevalent in older patients, the association with advanced age and severity of the disease is confounding. The aim of this study was to assess changes in the prevalence of HCV genotypes by surveying a large population of chronic hepatitis C patients in Northern Italy, and to assess if the high prevalence of genotype 1b in older patients with advanced diseases simply reflects the duration of HCV infection, rather than intrinsic biological properties of HCV. METHODS: We studied 1368 HCV-RNA positive patients, with histologically proven chronic hepatitis. Drug addiction, blood transfusions and sporadically acquired infections represented the risk factors. RESULTS: Genotype 1b, the most prevalent isolate, and genotype 2a were associated with older age, cirrhosis, sporadically-acquired infections and blood transfusion, while types 1a, 3a, and 4 were associated with younger age, chronic persistent hepatitis and drug addiction. Patients with a history of transfusions were divided into four groups depending on the period of transfusion. The prevalence of genotype 1b decreased with time. Type 3a appeared only after 1979. CONCLUSION: The severity of chronic hepatitis C could be related more to the duration of the infection rather than to the intrinsic pathogenicity of HCV genotypes.

Adolescent↗
PubMed1998

Increased levels of elastase and alpha1-antitrypsin in sputum of asthmatic patients.

Asthma and chronic bronchitis are inflammatory diseases associated with remodeling of the extracellular matrix (ECM). Elastin, a major component of the ECM in the airways, has been previously found to be disrupted in asthma and chronic bronchitis. This study was aimed at evaluating whether elastin disruption might be associated with an imbalance between elastase (active and total) and alpha1-proteinase inhibitor (alpha1-PI), the main inhibitor of elastase. We measured elastase and alpha1-PI in induced sputum obtained from 16 control subjects, 10 healthy smokers, 19 asthmatic patients, and 10 chronic bronchitis patients. We also assessed the possible origin of elastase, evaluating its levels in sputum with reference to differential cell counts. We found that in induced sputum obtained from asthmatic and chronic bronchitis patients, the levels of both total and active elastase were significantly increased as compared with those of control subjects and healthy smokers and were significantly correlated with the percentage of neutrophils. In addition, in asthma and chronic bronchitis patients, the levels of active and total elastase were inversely correlated with the degree of airway obstruction as assessed from FEV1 values. This study shows that airway inflammation in asthma and chronic bronchitis is associated with high levels of active elastase, which may play a role in the pathogenesis of airway remodeling.

Adult↗
PubMed1998

Sputum metalloproteinase-9/tissue inhibitor of metalloproteinase-1 ratio correlates with airflow obstruction in asthma and chronic bronchitis.

Asthma and chronic bronchitis are inflammatory diseases with extracellular matrix (ECM) remodeling and collagen deposition. Collagen homeostasis is controlled by metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs). We evaluated MMP and TIMP balance in induced sputum of 10 control, 31 untreated asthmatic, and 16 chronic bronchitic subjects. We first performed zymographic analysis to identify the profile of MMPs. Zymography revealed a similar MMPs profile in all populations studied and that MMP-9 was the major enzyme released. We then measured, using enzyme immunoassay, the concentrations of MMP-9 and of its inhibitor TIMP-1 and evaluated whether airflow limitation may be associated with an imbalance between these enzymes. MMP-9 and TIMP-1 concentrations were greater in sputum of patients with asthma and chronic bronchitis than in control subjects. The molar ratio between MMP-9 and TIMP-1 was lower in asthmatics and chronic bronchitics than in control subjects, and positively correlated with FEV1 values. In asthma, MMP-9 levels were significantly correlated with the number of macrophages and neutrophils. This study shows that airway inflammation in asthma and chronic bronchitis is associated with an imbalance between MMP-9 and TIMP-1 which may have a role in the pathogenesis of ECM remodeling and airflow obstruction.

Adolescent↗
PubMed1998

Effect of age upon airway obstruction and reversibility in adult patients with asthma.

OBJECTIVE: In a cross-sectional study we evaluated the effect of aging (separately from that of duration of disease) on airway obstruction and reversibility by comparing two groups of non-smoker patients with asthma. METHODS: We compared two groups of patients: group A, which had 50 subjects (8 men and 42 women) aged 59.7+/-4.6 years (mean +/- SD), and group B, comprised of 51 subjects (19 men and 32 women) who were 35.7+/-7.4 years old. The groups were selected because of comparable baseline degree of obstruction (FEV1 % of predicted, 67.8+/-20.3 in group A; 73.0+/-19.6 in group B, NS) and duration of the disease (14.0+/-11.7 years vs 11.2+/-9.1, NS). Spirometric examination, with a bronchodilator test, was performed and subjects not reaching 85% of predicted were submitted to a 4-week course of inhaled steroids. RESULTS: Although a higher number of subjects from group B responded to the acute bronchodilator test (p < 0.001), the maximum response achievable with treatment (steroid or bronchodilator) (deltaFEV1 expressed as the percent of predicted) was not statistically different between groups (12.0+/-17.5 vs 16.0+/-23.9). The mean FEV1 attainable after treatment (deltaFEV1%PT) was significantly lower in the older group (p = 0.0006). Within groups, the baseline FEV1% did not correlate with age; it was inversely correlated with the duration of the disease (p < 0.03 and p < 0.01, respectively). In both groups deltaFEV1 was inversely related with the baseline FEV1, whereas FEV1%PT was correlated with the duration of the disease, with a slope nearly doubled in group B (p < 0.001). CONCLUSIONS: Both the process of aging and the prolonged exposure to disease effects are important factors in determining the functional characteristics of chronic asthma: In particular, aging is associated not only with a reduced acute responsiveness to bronchodilators, but also with a reduced slope of the duration-FEV1%PT relationship that suggests a slowing of the rate of loss of reversibility of uncertain biological meaning.

Adult↗
PubMed1997

Evaluation of diaphragmatic fatigue in obstructive sleep apnoeas during non-REM sleep.

BACKGROUND: Resistive load applied to the airways may induce diaphragmatic fatigue, and hypoxaemia has been shown to predispose to the development of fatigue. Inspiratory muscle fatigue may occur in patients with obstructive sleep apnoea syndrome (OSAS), as these patients repetitively develop both inspiratory loading and hypoxaemia. The results of previous studies on this topic are inconclusive, probably because of the methodological approaches used. METHODS: Six obese patients with OSAS underwent a polysomnographic study. The diaphragmatic pressure time index (PTI) was evaluated as an indicator of diaphragmatic contraction, and the mean frequency of the diaphragmatic electromyogram power spectrum (Fm) and the maximum relaxation rate of transdiaphragmatic pressure (MRR) as indices of a fatiguing diaphragm. A total of 119 randomly selected apnoeas (each including 5-13 occluded efforts) were analysed throughout the night in non-REM sleep to assess possible muscle fatigue due to the high pressure generation in each apnoea. A breath-by-breath within-apnoea analysis was performed on the first three pre-apnoeic breaths, on all the occluded efforts, and on the first three unoccluded breaths following the apnoea interruption. Possible fatigue development due to the cumulative effect of apnoeas over the night was also evaluated. RESULTS: A progressive increase of Fm and MRR was found during the obstructive phase in all the subjects in the within-apnoea analysis. The overnight analysis did not show a reduction in either PTI, Fm, or MRR secondary to recurrent upper airway obstruction during the night. CONCLUSIONS: No evidence of diaphragmatic fatigue or impaired diaphragmatic contraction was found either within each apnoea or throughout the whole night, despite the generation of high PTI values during the apnoeic occluded phases. It is concluded that diaphragmatic fatigue does not occur in OSAS during non-REM sleep.

Adult↗
PubMed1997

Transforming growth factor-beta expression in mucosal biopsies in asthma and chronic bronchitis.

We assessed whether transforming growth factor-beta (TGF-beta), a fibrogenic growth factor, may be involved in remodeling of asthma and chronic bronchitis; its expression was compared with that of epidermal growth factor (EGF) and granulocyte macrophage colony-stimulating factor (GM-CSF) in bronchial mucosal biopsies from 13 normal subjects, 24 asthmatics, and 19 patients with chronic bronchitis. TGF-beta immunoreactivity was highly increased in epithelium and submucosa of those with bronchitis and to a lesser extent in asthmatics. By comparison, with normal subjects, EGF immunoreactivity was significantly increased in the epithelium of bronchitic subjects and submucosa of asthmatics, and, GM-CSF immunoreactivity was increased in both epithelial and submucosal cells of asthmatics and to a lesser extent in submucosa of bronchitics. A significant correlation was found between the number of epithelial or submucosal cells expressing TGF-beta in both asthma and chronic bronchitis and basement membrane thickness and fibroblast number. No such correlation was found for EGF or GM-CSF. in situ hybridization for TGF-beta 1 mRNA confirmed the results obtained by immunohistochemistry. By combining in situ hybridization and immunohistochemistry, it was found that eosinophils and fibroblasts were synthetizing TGF-beta in asthma and bronchitis. These data suggest that TGF-beta, but not EGF or GM-CSF, is involved in airways remodeling in asthma and chronic bronchitis.

Adolescent↗
PubMed1997

Effect of ageing on peak expiratory flow variability and nocturnal exacerbations in bronchial asthma.

The aim of this study was to evaluate the role of ageing on variability of airflow obstruction and on the specific pattern of nocturnal exacerbations ("morning dipping" of peak expiratory flow (PEF)) in asthma. Two groups of stable asthmatics (Group A: 23 patients, aged 14-47 yrs; Group B: 20 patients, aged 53-74 yrs), that were similar for duration of disease, degree of obstruction and response to bronchodilators, were studied. PEF was monitored four times daily for 2 weeks, and amplitude of variation and "morning dip" were calculated. Both PEF amplitude and "morning dip" were greater in the older patients (p<0.005). Amplitude was negatively correlated with baseline forced expiratory volume in one second (FEV1) in both groups (p<0.01); multiple correlation with age, duration of disease, baseline FEV1 and degree of reversibility was significant in the older group only. Morning dip was inversely correlated to baseline FEV1 (p<0.01) and reversibility (p<0.05). Nocturnal symptoms were reported by all of the five Group A "dippers", but by only 6 of the 13 Group B "dippers" (p<0.04). Ageing contributes to increased variability of airway calibre in asthma. Aged patients are potentially at risk because functional evidence of nocturnal asthma may frequently be accompanied by a poor subjective awareness. Therefore, a more extensive practice of PEF monitoring is recommended in aged asthmatics.

Adolescent↗
PubMed1996

Urinary leukotriene E4 in the assessment of nocturnal asthma.

BACKGROUND: Urinary leukotriene E4 (LTE4) is a marker of the body's production of cysteinyl LTs, important mediators of airway inflammation. The role of the latter in nocturnal asthma is a topic of increasing interest. OBJECTIVE: This investigation was aimed at determining whether nighttime attacks are associated with increased release of LTs, expressed by urinary LTE4, and the relationship between the two phenomena. METHODS: Three groups were studied: group A, seven control subjects; group B, nine asthmatic patients without nocturnal attacks; and group C, nine asthmatic patients with a comparable daytime FEV1 but who were experiencing nocturnal exacerbations (morning dips in peak expiratory flow greater than 20%). Urine was collected over 24 hours in three samples (9:00 AM to 3:00 PM; 3:00 PM to 9:00 PM; and 9:00 PM to 9:00 AM). LTE4 was measured by high-performance liquid chromatography and radioimmunoassay and expressed as nanograms per millimole of creatinine. RESULTS: No significant differences between urinary LTE4 were noticed within groups A and B. Conversely, in group C urinary LTE4 at night (geometric mean with 95% confidence interval; 35.16 with 28.77-42.85) was significantly higher than that of the other samples (respectively 23.12 with 17.78-30.06, p less than 0.05; and 25.18 with 21.03-30.13, p less than 0.02); it was also significantly higher than in all the samples of other groups. A significant (p less than 0.02) linear correlation was observed between morning dip in peak expiratory flow and the log urinary LTE4 in the nocturnal sample. CONCLUSION: These results indicate the role of LTs in nocturnal asthma and suggest that urinary LTE4 may be a useful marker of this condition.

Activity Cycles↗
PubMed1996

Release of transforming growth factor-beta (TGF-beta) and fibronectin by alveolar macrophages in airway diseases.

Asthma and chronic bronchitis are associated with airway remodelling, and airway macrophages are present in bronchial inflammation. TGF-beta and fibronectin released by alveolar macrophages possess a fibrogenic potency. The potential role of alveolar macrophages in airway remodelling was studied in asthma and chronic bronchitis by the release of TGF-beta and fibronectin. Alveolar macrophages were isolated by bronchoalveolar lavage in 14 control subjects, 14 asthmatics and 14 chronic bronchitics. The spontaneous and lipopolysaccharide (LPS)- or concanavalin A (Con A)-induced release of TGF-beta and fibronectin was measured by ELISA. Alveolar macrophages from chronic bronchitics spontaneously release greater amounts of TGF-beta and fibronectin than those from asthmatic and control subjects. Alveolar macrophages from asthmatics release greater amounts of TGF-beta and fibronectin than those from control subjects. The spontaneous release of TGF-beta is significantly correlated with that of fibronectin. Fibronectin release was significantly reduced after LPS stimulation, and TGF-beta release was significantly increased after LPS stimulation, except in chronic bronchitis patients. Con A increased the release of TGF-beta in cells from normal subjects. This study suggests that activated macrophages play a role in airway remodelling in chronic bronchitis and to a lesser extent in asthma.

Adult↗
PubMed1996

Evaluation of nocturnal bronchoconstriction by all night tracheal sound monitoring.

BACKGROUND: A study was undertaken to evaluate the reliability of a digital tracheal sound analyser (ELENS-DSA) in predicting nocturnal changes in airways resistance in asthmatic patients. This device allows continuous measurement of the proportion of the time occupied by wheezing (Wh%). METHODS: Nocturnal polygraphic studies with simultaneous continuous monitoring of tracheal sounds and airways resistance were performed in seven patients with nocturnal asthma. In order to evaluate the possible bias in wheezing estimation, each tracheal sound recording was passed through the automatic analyser and simultaneously monitored with earphones by an experienced observer. RESULTS: The device detected audible wheezing with an optimal sensitivity and specificity of 70%. Snoring was a minor cause of the relatively poor characteristics of the system. A close correlation (p < 0.001) between Wh% and airways resistance was observed only in those patients with the highest increase in resistance; when the results of all the subjects were pooled the correlation observed was poor. The predictive value of Wh% in detecting changes in airways resistance during 10 minute intervals was lower than 70%. The positive and negative predictive values of Wh% were raised to 79% and 83%, respectively, for 30 minute intervals. CONCLUSIONS: The ELENS-DSA system is a relatively crude means of detecting wheezing and assessing bronchoconstriction quantitatively. However, it is able to detect accurately nocturnal bronchoconstriction for 30 minute intervals. This finding, along with the fact that the monitoring is non-invasive, suggests that it may be a promising tool, especially for patients during sleep.

Adult↗
PubMed1996

[Reversible broncho-obstruction (asthma and COPD) in the elderly patient. Epidemiologic, diagnostic, and therapeutic features].

In the field of respiratory diseases during aging, obstructive diseases hold a prominent position because they are frequent and are potentially "tractable" and thus subjected to careful therapeutic intervention. Bronchial asthma and chronic obstructive pulmonary disease are most important clinical patterns. Bronchial asthma (in chronic and in uncommon, newly diagnosed, forms) in the elderly are more frequent than commonly known. Wider and deeper studies of chronic obstructive pulmonary disease, besides, have demonstrated that a component of reversibility is present even in the older patients, in a ratio of 20-40%. The reversible bronchial obstruction appears therefore, in the older patients, as a qualitatively and quantitatively important event, in the clinical and therapeutical field. The recent production of international Guidelines (ATS/ERS, 1995) gives the possibility--for this type of diseases--of utilizing more accurate diagnostic criteria and new therapeutic approaches.

Aged↗
PubMed1995

[Respiratory medicine in geriatrics. A cultural niche of relevant theoretical and practical importance].

Respiratory medicine in the elderly represents a topic of increasing interest in the developed countries, because of its peculiar clinical and therapeutical implications. In this respect, a deeper knowledge of the biology and physiology of aging lung is desirable: namely, the age-related immunological and structural changes involving the respiratory system do influence clinical presentation and response to the treatment in older people. A better understanding of the pharmacology in the elderly which is recognized to be different for several aspects from that of the general population, is mandatory in order to better approach these practical problems. This short review emphasizes the need of the "longitudinal", rather than "transversal", epidemiological surveys which are uniquely able to give useful information on the natural history, even in older populations. In addition, clinical and therapeutical peculiarities of some respiratory illnesses such as infectious lung diseases, including pulmonary tuberculosis, COLD and bronchial asthma, sleep-related respiratory disorders will be underlined. Finally, a few problems concerning the management of the geriatric subject with chronic respiratory disease will be analyzed, focusing mainly on the difficulties inherent in the inhalant therapy and functional evaluation of this kind of patients.

Aged↗
PubMed1994

Ventilatory response to spontaneous resistive load variations during sleep.

We investigated the ventilatory response to spontaneous changes in resistive load during sleep in nine adult asthmatic patients, four of whom were snorers. All patients had a history of nocturnal worsening of respiratory symptoms and were submitted to a nocturnal polysomnographic study in a sleep laboratory. During the night, all patients showed spontaneous increases in pulmonary resistance due to bronchoconstriction. A temporary additional increase in inspiratory resistance (RI) was observed as a result of snoring. In all patients, a highly significant inverse linear relationship was found between ventilation (VE) and RI, but the slopes of the regressions varied considerably among patients; the decrease in VE was due to a reduced mean inspiratory flow. The most effective ventilatory compensation to increasing resistive load (lowest absolute values in the VE/RI slopes) was observed in two patients: one nonsnorer and one snorer. Effective VE compensation appeared to be dependent on the individual's combined adjustments of transpulmonary pressure (Ptp) and duty cycle (TI/TT). In fact, an increase in Ptp, linearly related to RI, was observed in all patients except one (a snorer during nonsnoring breathing); however, the Ptp increase was able to compensate VE only when TI/TT increased. We conclude that, in sleeping asthmatic patients, VE adaptation to increased spontaneous load is highly variable among patients and its effectiveness is related to individual strategies on the basis of adequate adjustments of neuromuscular output and timing of the breathing cycle.

Adult↗
PubMed1994

Theophylline suppresses the release of tumour necrosis factor-alpha by blood monocytes and alveolar macrophages.

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 at 2 h and declined at 4 h (59 +/- 5.2% of controls) and 24 h (89 +/- 3.1% of controls). Northern analysis performed on ribonucleic acid (RNA) extracted from human BMo demonstrated that theophylline was able to reduce TNF-alpha gene expression. Comparable levels of inhibition of TNF-alpha release were observed on rat BMo and AM (rat BMo 42 +/- 4.9% of controls; rat AM 38 +/- 1.7% of controls), suggesting that BMo and AM are equally susceptible to suppression of TNF-alpha release induced by theophylline. These results indicate that theophylline suppresses TNF-alpha release by mononuclear phagocytes. Since TNF-alpha is involved in the pathogenesis of bronchial hyperresponsiveness and asthma, our results suggest that the therapeutic activity of theophylline might be partly related to its effect on TNF-alpha release.

Animals↗