PubMed Health⌕ Search

Biomedical subjects

G Carpentiere

Publications and source records attributed to G Carpentiere.

At least 19 recordsLinked to original sources
PubMed1990

Dose-related effect of beclomethasone dipropionate on airway responsiveness in asthma.

The effects of twice daily inhaled beclomethasone dipropionate (BDP) at two dose levels (500 and 1,000 micrograms daily) on the airway responsiveness to inhaled histamine was evaluated by a randomized, single-blind, cross-over study in 10 patients with stable asthma. The 12-week study began with a 3-week run-in period of baseline treatment, which was continued unchanged throughout the study, and the two treatment periods were separated by a 3-week placebo period. Patients attended the laboratory every 3 weeks for spirometry and histamine inhalation tests to determine the provocative concentration of histamine causing a 20% fall in forced expiratory volume in 1 s (PC20 of FEV1). There was a similar significant improvement (p less than 0.05) in mean FEV1 after both treatments. There was no significant change in PC20 after treatment with 500 micrograms daily, the geometric mean being 0.587 mg/ml after the placebo period and 0.860 mg/ml after BDP treatment. There was a significant improvement in PC20 (1.930 mg/ml) after treatment with 1,000 micrograms BDP daily in comparison with the placebo and treatment periods with 500 micrograms BDP daily (p less than 0.001). These results suggest that higher doses than usual of inhaled BDP must be used to control airway responsiveness in asthmatics.

Adult↗
PubMed1990

Effect of beclomethasone dipropionate on the bronchial responsiveness to propranolol in asthmatics.

The effect of four weeks of treatment with beclomethasone dipropionate (BDP, 500 micrograms twice daily) on the bronchial responsiveness to propranolol was examined in 16 patients with mild asthma in a placebo-controlled, double-blind crossover study. Propranolol was inhaled in doubling concentrations and the results were expressed as the cumulative dose producing a 20 percent fall in FEV1 (PC20). After four weeks of treatment with BDP, the mean FEV1 increased from 82.0 percent predicted to 88.1 percent predicted. The difference was significant (p less than 0.001). Treatment with BDP did not significantly change the responsiveness to propranolol, the geometric mean PC20 being 3.17 mg/ml before and 3.64 mg/ml after BDP treatment. The recovery of FEV1 was faster after 60 minutes of BDP treatment in comparison with placebo treatment (beyond 90 minutes). This study suggests that BDP treatment is unable to reduce bronchial responsiveness to propranolol but can accelerate the recovery of bronchoconstriction induced by propranolol in asthmatic patients.

Administration, Inhalation↗
PubMed1988

Increased responsiveness to histamine after propranolol in subjects with asthma nonresponsive to the bronchoconstrictive effect of propranolol.

Eight nonsmoking subjects with asthma, nonresponsive to the bronchoconstrictive effect of oral propranolol, were studied. The airway response to increasing concentrations of histamine aerosol was assessed by measuring FEV1. The threshold provocative dose of histamine needed to cause a 20% fall in starting FEV1 (PD20) was measured by log dose-response curve. Histamine challenge was performed in duplicate after premedication with placebo or 40 mg of propranolol on separate days. The mean starting FEV1 did not change significantly after placebo and after propranolol administration. The mean PD20 values after propranolol (0.37 mg/ml and 0.32 mg/ml, respectively, for the first and the second challenge) were significantly lower (p less than 0.01) than mean control PD20 values (1.36 mg/ml and 1.48 mg/ml, respectively, for the first and the second challenge). These results indicate that propranolol increases airway responsiveness to histamine, even in those subjects with asthma in whom propranolol has little bronchoconstrictive effect.

Adult↗
PubMed1988

Effect of ketotifen on the bronchodilation induced by salbutamol.

Twelve subjects with stable asthma each inhaled two puffs (200 micrograms) of salbutamol on 2 separate days 3 h after double-blind oral administration of ketotifen (two 1-mg capsules) or identical placebo. FEV1 was recorded before and at intervals for 4 h after inhalation of salbutamol. Overall, the FEV1 was significantly greater during the 4-hour period after premedication with ketotifen (p less than 0.02) and the difference between the effect of placebo and ketotifen was statistically significant at 120, 180 and 240 min after salbutamol (p less than 0.05).

Adult↗
PubMed1988

Airway responsiveness to histamine in patients refractory to repeated exercise.

To investigate the mechanisms contributing to refractoriness in exercise-induced asthma (EIA), airway responsiveness to histamine was studied in eight asthmatic patients. Patients were included in the study on the basis of their refractory response to multiple exercise challenges. Incremental challenges with inhaled histamine were performed at rest and 40 minutes after single and paired exercise tests. The geometric mean histamine concentration required to produce a 20 percent fall in FEV1 (PC20) for the challenge after paired exercise test (4.34 mg/ml) was significantly higher (p greater than 0.001) than those for the challenges after a single exercise (1.05 mg/ml) and for the challenge at rest (0.67 mg/ml). There was no significant difference between PC20 values at rest and after a single exercise test (p greater than 0.05). The results show that the response to histamine is reduced during the refractory period following paired exercise test.

Adult↗
PubMed1987

Effect throughout the day of inhaled fenoterol on the bronchial responsiveness to histamine in asthmatic patients.

The effect throughout the day of inhaled fenoterol on the bronchial responsiveness to inhaled histamine was evaluated in 8 asthmatic patients. The airway response to increasing concentration of histamine aerosol was assessed by measurement of forced expiratory volume in one second (FEV1). The provocative dose of histamine needed to cause a 20% fall in starting FEV1 was calculated from the cumulative log dose response curves. Histamine challenges were performed in duplicate, on separate days, after premedication with placebo or fenoterol given by metered dose inhalers in the morning and in the afternoon. The mean starting FEV1 in the morning and in the afternoon did not change significantly after placebo inhaler, but fenoterol caused a mean increase in FEV1 of 11.11% in the morning and 4.92% in the afternoon. Geometric mean histamine PC20 was significantly higher after fenoterol than after placebo. After fenoterol there was no significant difference between morning and afternoon geometric mean histamine PC20. No relation was found between bronchodilatation achieved by fenoterol and increase in the geometric mean histamine PC20 (p greater than 0.05). There was instead a significant relationship between starting FEV1 and histamine PC20 in the morning and in the afternoon both after placebo and fenoterol.

Adolescent↗
PubMed1985

Oral sustained-release aminophylline and bronchodilator response to inhaled fenoterol in patients with chronic airflow obstruction.

The bronchodilator response to inhaled fenoterol (400 micrograms) was examined in the morning and in the afternoon before and during oral sustained-release aminophylline treatment in eight patients with chronic reversible airway obstruction. Bronchodilatation was evaluated by measuring serial peak expiratory flow rates (PEFR) for eight hours after inhaled fenoterol and calculating the area under the time-response curves and the percentage increment from the baseline values. The patients showed an enhancement of the bronchodilatation achieved with fenoterol in the morning during aminophylline treatment. In the afternoon, instead, the effect of the fenoterol was not improved by oral aminophylline. This different effect of oral aminophylline might depend on the variable degree of potential reversibility present or diurnal variation in the bronchial response.

Aerosols↗
PubMed1985

Influence of the administration time on the antihypertensive and hypokalaemic effects of chlorthalidone in patients with primary hypertension.

A double-blind crossover study was designed to compare the antihypertensive and hypokalaemic effects of chlorthalidone administered at 10h00 and 22h00 to sixteen patients with primary hypertension. Blood pressure values during chlorthalidone treatment at 10h00 did not differ significantly from those at 22h00. Significant correlation (r = 0.8987) was seen, however, only between the patients' blood pressure during the placebo period and the fall in blood pressure obtained by administration of chlorthalidone at 22h00. The serum potassium level fell significantly (p less than 0.01) during morning treatment while a slight, insignificant fall was found during evening treatment. No correlation was seen between decrease in blood pressure and decrease in serum potassium level.

Adult↗
PubMed1984

[Effects of delayed-action metoprolol evaluated in hypertensive patients responsive to therapy subdivided in 2 different age groups].

Thirty patients with essential hypertension, whose blood pressure was controlled by metoprolol, were divided according to age in two groups. All the patients were treated with long-acting metoprolol given as simple daily dose at 08.00 h. Blood pressure and heart rate were recorded before and at the 7th, 15th, 30th, 45th, 60th days of treatment. No significant difference in the antihypertensive effects of metoprolol was detected between the two groups of patients. A significantly higher reduction of the heart rate was observed in the older patients.

Adult↗
PubMed1983

Effects of inhaled fenoterol on the circadian rhythm of expiratory flow in allergic bronchial asthma.

Metered-dose aerosol treatment with fenoterol for three consecutive days, in eight patients suffering from allergic asthma, caused the disappearance of FEV1 and MEF50 circadian rhythm. We attribute such behavior to the suppression of the bronchomotor tone induced by fenoterol. The administration on different days of a single dose of fenoterol aerosol in another group of eight patients pointed out the variability of the effects of the drug at different hours of the day. We believe the results obtained are important for a better dosage and time distribution of the therapy with beta2 agonists.

Adult↗
PubMed1978

[Effects of isoprenaline bronchodilation on the partial pressure of oxygen in various clinical forms of bronchial asthma].

Blood gas disturbances noted in recent asthma were fully corrected with 1% isoprenalin aerosol, though changes in PaO2 were usually unobtainable in patients with chronic bronchopneumopathic obstruction. Simultaneous administration of 70% hyperoxygenated air via an intermittent positive pressure respirator led to a significant increase in this parameter, but was rarely followed by normalisation of the blood gas picture. It is considered that this finding is attributable to increased anatomical shunt at the alveolocapillary level.

Adult↗