Biomedical subjects

W Arossa

Publications and source records attributed to W Arossa.

At least 19 recordsLinked to original sources

PubMed2003

Tuberculin reactivity in adult BCG-vaccinated subjects: a cross-sectional study.

INTRODUCTION: Interpretation of the tuberculin skin test (TST) may be complicated by prior bacille Calmette-Guérin (BCG) vaccination. The skin reaction to the vaccination interferes with the management of individuals who may be infected with Mycobacterium tuberculosis. OBJECTIVE: To discriminate between TST reactions due to infection and those due to vaccination in subjects with unknown BCG status. METHODS: Among 60200 subjects tested with 5TU PPD for screening purposes, 4987 contacts of infectious TB cases (Group A), 4962 BCG-vaccinated subjects (Group B) and 5000 subjects from the general population (Group C) were sampled. The frequencies of TST cut-off diameters were calculated for the three groups using a logistic regression model. The frequency of positive subjects in each group and the sensitivity, specificity and predictive values were also computed by means of these cut-offs. RESULTS: The risk of being a contact versus BCG-vaccinated increases 2.43-fold with every mm of TST diameter. The 11 mm cut-off point seems to be the best discriminating value. CONCLUSIONS: Using the traditional 10 mm cut-off, we can consider all vaccinated subjects with a positive TST to be infected. The TST remains a valuable tool for the evaluation of household contacts and suspected cases of tuberculosis in BCG-vaccinated subjects and in populations with high vaccination coverage.

Adolescent↗

PubMed1998

Predictors of survival in a group of patients with chronic airflow obstruction.

This article shows the results of a 10-year follow-up study conducted on a cohort of 870 patients affected by severe chronic airflow obstruction (CAO) on spirometric tests. The main aims of the study were to identify those factors associated with reduced survival in CAO patients and to evaluate the effectiveness of a care program on patients' survival. The analysis compared the survival time and causes of death between patients who showed adherence and patients who did not show adherence to the care program. The most important results can be summarized as follows: (1) CAO patients have a high mortality rate for acute respiratory failure, cor-pulmonale, and lung cancer; (2) patient's age at the time of selection to enter follow-up influences the death hazard; (3) patients who need long-term oxygen treatment (LTOT) have a higher death hazard than those who don't need it; (4) the higher is FEV1 or PaO2 value at the time of selection, the lower the death hazard; (5) patients who need, and regularly take, long-term oxygen treatment have a lower death hazard compared to those who need it, but do not take it properly; and (6) patients with a partial reversible airway obstruction (pRAO) who regularly attend the clinic for planned check-ups, have a lower death hazard compared to those who have the same characteristics, but do not show adherence to the care program. These results indicate that an organized program to treat severe CAO patients may improve their survival.

Adult↗

PubMed1997

Tobacco smoke habits in a group of adolescents: responsibility of the cohabitants in the active and passive exposure.

Several studies in adults demonstrated a positive relationship between the number of cigarettes smoked and the urinary cotinine. The aim of this work was to analyze the passive and active smoking exposure of 333 sixteen-year-old students, demonstrated by their urinary cotinine, in comparison with the smoking habits of all the cohabitants. This last information was obtained from a questionnaire and urinary cotinine in mothers. The second purpose of this work was to observe whether the smoking habits of parents can promote the voluntary active exposure to tobacco smoke in children. The considered students represent a particular group of people (16 years old) having a life-style still strictly bound to the smoking habit of parents. In fact, the nonactive smokers show urinary cotinine levels described by the following means: 28.81, 39.35, 39.62, and 57.67 ng/mL. This finding demonstrates a trend of exposure from no exposure to a maximum level of passive exposure. Similar results can be observed by considering the urinary cotinine of mothers. Finally, the active smoking habit potentially acquired by the adolescents seems to be induced also by emulation of the smoking habits of fathers. This possibility is demonstrated by a light positive and statistically significative correlation with the number of cigarettes actively smoked and, consequently, with urinary cotinine.

Adolescent↗

PubMed1993

[The impact of immigration from high incidence countries on the epidemiology of tuberculosis].

Immigration in Italy from developing countries is a recent problem and the possible consequences on public health must be taken into account. The present study reports the results of Tuberculosis control activities performed by the Dispensario di Igiene Sociale of Turin, related to this population. Up to now the available data suggest that the immigrant population (mainly from North Africa and Senegal), in spite of representing a small part of residents (approximately 33,000/1,000,000) contributes to one third of Tuberculosis cases. The consequences on Tuberculosis epidemiology in Italy and our operational experience on Tuberculosis control and prevention are discussed.

Emigration and Immigration↗

PubMed1991

Prolonged gastric pH monitoring in responder and nonresponder duodenal ulcer patients: response to placebo and to H2-blocker administration.

We evaluated the circadian pattern of gastric acidity by prolonged intraluminal pHmetry in 15 "responder" and 10 "nonresponder" duodenal ulcer patients after nocturnal administration of placebo, ranitidine, and famotidine. Acidity was measured during predefined periods under the different drug regimens in the two groups of subjects, and a comparison was performed both within and between groups. With placebo, significantly lower median 24-h pH values were detected in patients with resistant ulcer than in responders (1.13 versus 1.63). On the contrary, no statistical difference was detected between the two groups during any time of day after administration of either ranitidine or famotidine. Within each group, no significant difference was noted between the two different H2-blockers. Thus, our data suggest that patients with resistant duodenal ulcer display an increased gastric acidity in control conditions but a "normal" response to administration of antisecretory drugs.

Adult↗

PubMed1989

Effect of ascorbic acid on increased bronchial responsiveness during upper airway infection.

We investigated the acute effect of ascorbic acid on histamine bronchial responsiveness (PC 20: concentration causing a 20% fall in FEV1) in 9 hospital staff members with upper respiratory tract infection (URI) and cough. Subjects were examined within 5 days from the start of illness and 6 weeks after. On day 1, the reproducibility of PC20 was assessed by 2 consecutive inhalation challenges 1 h apart; the two values were closely related (r = 0.96, p less than 0.001). Five subjects had bronchial hyperresponsiveness (PC20 less than 8 mg/ml histamine). On the following day, PC20 was measured before and 1 h after oral intake of 2 g ascorbic acid. Vitamin C produced a significant increase in average PC20 (p less than 0.01) from 7.8 +/- (SE) 1.2 to 25.1 +/- (SE) 1.2 mg/ml. None had airway hyperresponsiveness after treatment. Six weeks after the onset of URI, bronchial responsiveness was normal in all the subjects but one. The mean PC20 was 15.5 +/- (SE) 1.25 mg/ml, significantly higher than during URI (p less than 0.05); after ascorbic acid it increased nonsignificantly to 25.7 +/- (SE) 1.35 mg/ml. Our results indicate that vitamin C inhibits the transient increase in bronchial responsiveness occurring in otherwise normal subjects during URI.

Adult↗

PubMed1989

Effects of vitamin C on airway responsiveness to inhaled histamine in heavy smokers.

Histamine bronchial threshold, the provocation concentration of histamine causing a 25% fall in maximal expiratory flow at 50% of forced vital capacity from the control value (PC25MEF50), was measured in seven heavy smokers and in seven sex- and age-matched nonsmokers before and one hour after ingestion, double-blind, of vitamin C (2 g) or placebo. Smokers had significantly lower baseline values of serum ascorbate, maximal expiratory flow at 50% of forced vital capacity (MEF50) and PC25MEF50: the latter was negatively related to serum ascorbate (r = -0.85; p less than 0.001). Acute treatment with vitamin C produced a significant decrease in PC25MEF50 in smokers (95% confidence limit (CL) from 4.87-3.36 to 2.91-2.01 mg.ml-1; p = 0.017), whilst it had no effect in nonsmokers. A preliminary open study on the effect of prolonged administration of vitamin C (1 g daily) was performed in smokers. One week of treatment produced a further significant decrease in PC25MEF50 (p less than 0.0001). Our results suggest that in heavy smokers histamine bronchial responsiveness may be attenuated by chronic ascorbate deficiency. In these circumstances, acute and short-term treatment with vitamin C may increase the bronchoconstrictive response to inhaled histamine.

Adult↗

PubMed1988

Acute effect of intravenous magnesium sulfate on airway obstruction of asthmatic patients.

The bronchodilating effect of magnesium sulfate (MgSO4) was studied in ten asthmatic patients with moderate to severe airway obstruction. Two grams of MgSO4 or saline in double-blind crossover design was administered IV for 20 minutes (0.40 mmol/min) and forced expiratory capacity and forced expiratory volume in one second (FEV1) were studied at intervals. Only at the end of MgSO4 infusion did FEV1 increase significantly (109% of initial values). The bronchodilating effect was short lasting and far less than that observed after salbutamol.

Adult↗

PubMed1988

Daily gastric pH in controls and in duodenal ulcer patients: basal condition and response to treatment.

Gastric pH was monitored, by means of a computerized system, in healthy controls (C) and in patients with active duodenal ulcer (ADU) and inactive duodenal ulcer (IDU). The test was performed before treatment and during administration of a single dose of ranitidine 150 mg, cimetidine 400 mg, and pirenzepine 50 mg, in random sequence at 12-h intervals, (10 am, 10 pm). Under basal conditions, progressively lower median pH values were detected in ADU and IDU patients, compared with controls. A significant difference was found between C and ADU during daytime (1.38 vs. 0.85), nighttime (1.29 vs. 0.81), and 24 h (1.35 vs. 0.81) and between C and IDU during 24 h (1.35 vs. 1.11). However, no statistical difference was observed between patients with active and inactive ulcer disease. Administration of ranitidine and cimetidine significantly increased gastric pH during nighttime but not during daytime. Ranitidine, at the doses studied, proved to be more potent than cimetidine in suppressing gastric acidity. Gastric pH was unaffected by pirenzepine in most cases.

Adult↗

PubMed1987

Reduction of histamine-induced bronchoconstriction by magnesium in asthmatic subjects.

The effects of inhaled MgSO4 on histamine bronchoprovocation test (BPT) were studied in nine asthmatics in clinical remission (FEV1 greater than 80% of predicted). Patients performed histamine BPT on 2 separate days, one day after saline and the other after MgSO4 inhalation, in a randomized double-blind design. Spirometry and flow/volume curve were recorded on each test day before and 5 min after NaCl or MgSO4. No significant difference was observed in lung function measurements 2 days before and after either NaCl or MgSO4. The dose of histamine which produced a 20% decrease in control FEV1 (PD20FEV1) was significantly increased by aerosolized MgSO4 (from 0.177 +/- 0.036 mg after NaCl to 0.350 +/- 0.085 after MgSO4, P less than 0.05. After MgSO4 the dose-steps of histamine concentration increased two-fold in two subjects and one-fold in five.

Administration, Inhalation↗

PubMed1987

Magnesium attenuates methacholine-induced bronchoconstriction in asthmatics.

The effects of inhaled MgSO4 on methacholine bronchoprovocation test (BPT) were studied in 16 asthmatics in clinical remission (FEV1 greater than 80% of predicted). The patients performed methacholine BPT on two separate days, one day after saline, the other day after MgSO4 inhalation, in double-blind cross-over design. Spirometry was recorded on each test day before and 5 min after NaCl or MgSO4. Neither NaCl nor MgSO4 was found to have a significant effect on spirometric measurements. A significant inhibition of reactivity to methacholine was observed with an increase in log PD20 FEV1 from 1.31 +/- 0.11 inhalation units after NaCl to 1.56 +/- 0.11 inhalation units after MgSO4 (p less than 0.01). The most attractive hypothesis to explain the latter, is that Mg2+ might interfere with Ca2+ handling in the bronchial smooth muscle cells similar to that shown for other types of smooth muscle.

Adolescent↗

PubMed1986

Duration of oral procaterol protection from methacholine-induced bronchial obstruction.

The duration of action of procaterol, a beta-2-adrenoceptor agonist with an entirely new chemical structure, was assessed, in comparison to that of salbutamol, by inhalation of 43 inhalation units of methacholine at time intervals of 1, 3, 5, 7, and 9 hours after intake of the drugs. Procaterol and salbutamol were given in a double-blind random fashion, on different days, to 12 asthmatic children; pulmonary function tests (FVC, FEV1, MEF50, MEF25), skeletal muscle tremor, and vital signs (heart rate and blood pressure) were measured. Although there was no statistical significant difference between procaterol and salbutamol, protection of large and medium airways lasted for about five hours, while normal small airway patency was still present at seven hours. It is concluded that procaterol can be a good alternative beta-2-adrenoceptor agonist when the oral route is needed.

Adrenergic beta-Agonists↗

PubMed1986

Effect of nifedipine on salbutamol-induced bronchodilation in partially reversible airway obstruction.

The effects of the combination of oral nifedipine (20 mg) and inhaled salbutamol (400 mcg) were studied in ten stable patients with chronic partially reversible airway obstruction in a double-blind crossover design. Specific airway conductance (SGaw), forced expiratory volume in 1 second (FEV1), heart rate and blood pressure were recorded before and 30 min after administration of nifedipine or a placebo and 30, 60, 90, 150, 210 and 270 min after salbutamol inhalation. The mean value of FEV1 30 min after nifedipine was significantly (p less than 0.05) higher than after the placebo. The increase of SGaw and FEV1 produced by salbutamol was not significantly affected by pretreatment with nifedipine at any time. Nifedipine produced a significant increase of the heart rate which persisted throughout the study, but it did not influence blood pressure. No untoward effect was noticed during the study.

Adult↗

PubMed1985

A multivariate analysis of the risk in chronic obstructive lung disease (COLD).

This study was undertaken to assess the validity of cluster analysis for stratifying patients with severe COLD into homogenous subgroups in view of further prospective studies. To this aim, physiological measurements and questionnaire data were obtained from 532 outpatients with severe COLD (e.g. a 1 sec forced expiratory volume (FEV1) below 1.5-1/sec). The model variables selected for the partition in cluster were FEV1, PaO2, response to bronchodilators and heart rate. Two subgroups of patients were identified by the analysis: cluster I with significantly greater physiological impairment than cluster II. The comparison of the prevalences of the variables outside the model between the 2 clusters showed, in fact, that cluster I had a significantly higher prevalence of subjects with heavy smoking (p less than 0.01), prolonged occupational exposure (p less than 0.05), low body weight (p less than 0.05), recent hospitalizations for respiratory troubles (p less than 0.02) and emphysema (p less than 0.01). In conclusion, cluster analysis based on few physiological variables was able to identify, among patients with severe COLD, those with poorer general conditions and higher exposure to specific risk factors, for whom a worse prognosis of life can be expected. The advantages of cluster analysis in comparison to other techniques of classification in this kind of patient is discussed.

Analysis of Variance↗

PubMed1985

Salbutamol plus beclomethasone dipropionate versus theophylline for the prevention of methacholine-induced bronchospasm in patients with chronic bronchitis.

Forty patients suffering from chronic bronchitis with basal forced expiratory volume in one second (FEV1) values at least 20% below ECSC (European Community Steel and Coal) predicted values were treated with a combination of salbutamol plus beclomethasone dipropionate or with theophylline for a period of 4 weeks. Methacholine bronchial inhalation challenges were performed before and after treatment. Both treatments produced significant increases in FEV1, forced vital capacity (FVC) and FEV1 100/FVC, while only the salbutamol plus beclomethasone dipropionate combination significantly reduced the decrease in FEV1 values after bronchial inhalation challenge.

Adult↗

PubMed1984

Pulmonary involvement in chronic pancreatitis.

Although the association between acute pancreatitis and pleuropulmonary damage is well documented, so far no information on lung function in patients with chronic pancreatitis is available. In this study functional, radiological, and clinical investigations have been carried out in 42 patients affected by chronic calcific pancreatitis (CCP) and in 50 controls in a case-control study. An impairment of pulmonary diffusing capacity has been detected in CCP patients, while all the parameters of ventilatory function were not different from controls. This finding suggests the presence of early lung parenchymal damage in chronic pancreatitis secondary to either emphysema or pulmonary fibrosis.

Adult↗

PubMed1984

Different performance of two commercial nebulizers.

Two different nebulizers, the DeVilbiss 646 and the Mefar were tested for differences in output characteristics (air flow rate, amount of nebulized liquid and particle size) and it was found that there is a high variability between nebulizers of both brands. In the light of these findings, neither of these devices can be chosen as a standard nebulizer for bronchial provocation.

Aerosols↗

PubMed1983

Diagnostic value of serum bile acids and routine liver function tests in hepatobiliary diseases. Sensitivity, specificity, and predictive value.

Total serum bile acids measured by enzymatic fluorometry and routine liver function tests were determined in a large population including 97 healthy subjects, 138 patients free of hepatobiliary diseases but affected by other diseases, and 344 patients with mild or severe hepatobiliary diseases. In order to define the diagnostic value and some operational characteristics of serum bile acids, sensitivity, specificity, and several predictive value tables for increasing cutoff levels of serum bile acids were calculated by means of a computer program. Serum bile acids and aspartate aminotransferase were found to be similar in sensitivity, specificity, and predictive value. Serum aspartate aminotransferase was found to be more suitable than serum bile acids in detecting mild hepatobiliary diseases, whereas serum bile acids were more sensitive than routine liver tests in the evaluation of severe hepatobiliary diseases. In view of its ability to detect severe hepatobiliary diseases, serum bile acids test may play a decisive role in clinical practice (eg, decision to perform a liver biopsy).

Adolescent↗