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Biomedical subjects

A Taytard

Publications and source records attributed to A Taytard.

At least 91 records · Page 5Linked to original sources
PubMed1989

[Calcium antagonists and chronic obstructive bronchopneumopathies].

Calcium ion acts as a second messenger in numerous cellular functions. The increase in its intracellular free concentration, which is brought about by influx from the extracellular source through voltage-dependent or receptor-operated channels and/or by release from intracellular sources, triggers the contraction of smooth muscle. The currently available calcium antagonists inhibit calcium movement through voltage-dependent channels. Tracheobronchial and pulmonary vascular smooth muscles play an important role in the symptomatic expression of chronic airflow obstruction. Whether an alteration in their functioning is involved in the pathogenic mechanism of the disease has not yet been established. The contraction of bronchial smooth muscle participates in bronchial obstruction and that of vascular muscle in pulmonary arterial hypertension, which complicates hypoxemic airflow obstruction. Numerous clinical and experimental studies show that bronchodilator or anti-bronchoconstrictor effects of calcium antagonists are limited. This limitation may be linked to either a low affinity of calcium antagonists for bronchial smooth muscle or a specificity of the mechanism of excitation-contraction coupling in this muscle. Calcium antagonists are powerful inhibitors of hypoxic pulmonary vasoconstriction. This inhibition may lead to a worsening of hypoxemia in relation to redistribution of blood flow towards low ventilation/perfusion ratio areas although the concomitant rise in cardiac output leads to increased oxygen transport. These effects seem to be maintained in the long term.

Bronchi↗
PubMed1988

Respiratory function and bronchial reactivity in mill workers.

Professional exposure to vegetable dusts affect the respiratory function of the exposed subjects. A previous survey conducted in an industrial flour-mill demonstrated a higher frequency of respiratory symptoms in workers compared to a control group. Ten subjects employed in a work site particularly exposed to dust were studied. Each subject answered a questionnaire and performed on Mondays and Fridays, at the beginning and end of his work shift, a flow volume curve and an isocapnic hyperventilation test. The aerobiology of the professional environment was also measured. We noted: 1) in the flow volume curves: a drop in the FEV1 during the Monday morning shift, a significant difference between the FEV1 (p less than 0.05) and the MMEFR 25-75 (p less than 0.05) measured at 6 am on Monday and Friday, and between the MMEFR 25-75 values obtained at 12 noon on Monday and Friday (p less than 0.05). 2) after isocapnic hyperventilation, a significant drop in the MMEFR 25-75 at 6 am on Monday (p less than 0.01) and in the FEV1 and MMEFR 25-75 at 12 noon on Mondays (p less than 0.05), a significant drop in the FEV1 at 1 pm on Monday (p less than 0.01).

Adult↗
PubMed1988

Respiratory function in flour-mill workers.

The frequency of bronchial symptoms and the alteration of respiratory function parameters were studied in a group of 63 workers of an industrial flour-mill, and in a control group matched according to age, social class, and tobacco intake. In the exposed group the answers to a questionnaire indicated a greater incidence of cough (p less than 0.01) and chronic expectoration (p less than 0.01) as well as clinical airway hyperreactivity (p less than 0.01). No differences were noted for either asthma or allergy. The respiratory function parameters did not differ between the two groups studied. These results suggest that workers exposed to the vegetable dust found in fluor-mills are subject to develop chronic bronchial irritation.

Adult↗
PubMed1987

Prevention of exercise-induced asthma by oxitropium bromide.

A vagal mechanism appears to be involved in the development of exercise-induced asthma (EIA), although previous studies have failed to demonstrate a protective effect of anticholinergic drugs against post-exercise bronchoconstriction. To reassess this hypothesis the effect of a new anticholinergic drug, Oxitropium Bromide (OTB) has been studied in ten subjects with documented EIA. There was no change after inhalation of a placebo. Administration of OTB led to bronchodilatation and totally blocked post-exercise bronchoconstriction in 7 patients, and it did so partly in 2. The response to the drug appeared to depend on pretest respiratory function. Thus, the anticholinergic drug OTB may protect against EIA in most patients, confirming the role of a vagal cholinergic mechanism in EIA.

Adolescent↗
PubMed1987

Treatment of bronchial asthma with terfenadine; a randomized controlled trial.

1. Terfenadine, a histamine H1-receptor antagonist, was studied in 52 patients with stable mild perennial asthma with an allergic basis. 2. After a placebo run-in period, patients were randomly allocated to either terfenadine 120 mg twice daily or placebo. After 2 weeks they were crossed over to the other treatment. Forty-six patients completed the study. 3. Terfenadine was significantly more effective than placebo as measured by peak expiratory flows and by symptom scores. 4. These results suggest that histamine may play a more significant role in asthmatic bronchoconstriction than is currently recognised.

Adolescent↗
PubMed1987

Expiratory muscles and exercise limitation in patients with chronic obstructive pulmonary disease.

The aim of this study was to estimate, in patients with chronic obstructive pulmonary disease (COPD), the maximal strength of the expiratory muscles, its correlation with exercise performance and the effects of a specific physiotherapy. In 38 COPD men, aged 54 +/- 7 years, pulmonary function data, maximal alveolar pressure (Palv, max) developed during forced vital capacity, were measured using a whole-body plethysmograph and the maximal tolerated power (MTP), i.e. the highest power maintained for at least 3 min, was determined by a progressive test on a treadmill. Airway obstruction was severe (FEV1/FVC: 54 +/- 10%), Palv, max was lower than normal (74 +/- 36 vs. 130 +/- 48 hPa in 20 healthy men of the same age; p less than 0.01) and increased with airway resistance values (Raw); mean MTP was low: 115 +/- 30 W and individual values were inversely related to Raw values. Then, two subgroups of 14 patients were chosen at random. One subgroup received an abdominal muscle physiotherapy during 3 weeks. The other subgroup only received usual medical treatment. No modification in any parameter was found in the second subgroup. Specific physiotherapy of abdominal muscles improves significantly both Palv, max (118 +/- 45 hPa) and MTP (171 +/- 38 W; p less than 0.01), without any variation in other respiratory function parameters. We conclude that abdominal muscle weakness is common in COPD patients and can participate in the limitation in exercise performance. Specific physiotherapy increases abdominal muscle strength and seems to improve exercise tolerance by a still unexplained mechanism.

Humans↗
PubMed1987

[Asthma and synthetic antihistaminics].

Anti-histamines are considered weakly effective in the treatment of asthma whether in acute exacerbations or as basic therapy. However, there are numerous arguments which plead in their favour, and not only the recognised role of histamines as an important mediator of the immediate response. Besides, since 1948 when it was shown that the first anti-histamines (classical anti-histamines) possessed undeniable anti-histamine like actions, which showed them to have both broncho-dilator activity and a protective effect on bronchospasm induced by inhalation of histamine or allergens. Unfortunately, this efficacy in asthma is only achieved with high doses which are responsible for troublesome side-effects. This is why with the arrival of new anti-histamines specific for H1 receptors, without anti-cholinergic or sedative effects, one can envisage the day when high dose anti-histamines are evaluated in the treatment of asthma. Pharmacological studies in animals have clearly shown their bronchomotor action. Similarly, the first work carried out in men, confirms the anti-asthmatic potential by showing a protective action in the bronchial response, to isocapnic hyperventilation, to exercise and to allergens. As for anti-H2, their impact on asthmatic broncho-constriction is poorly defined: for some they potentiate, for others they inhibit.

Animals↗
PubMed1986

Platelet kinetics in stable atopic asthmatic patients.

The kinetics of platelets labeled with indium-111 were investigated in 13 healthy subjects as well as in 9 patients in the asymptomatic interattack stage of asthma. The survival times of platelets in healthy subjects was 8.9 +/- 1 days; in asthmatic subjects it was 4.7 +/- 1.3 days (p less than 0.001). The survival curve is of a biexponential form in asthmatics, thus suggesting the presence of 2 populations: one with a short life span (23 +/- 7 h), representing a third of the total population (33 +/- 9%), and the other with a normal life span. No single preferred site of platelet sequestration was found. These results suggest the presence of functional or anatomic lesions of platelets in asthmatic patients, which can be explained only hypothetically at the present time.

Adult↗
PubMed1986

[Synthetic anticholinergics: one more for treating asthma].

The author reports preliminary results and thinks that anticholinergics represent today a third drug group in asthma treatment. The anticholinergic interest in asthma treatment is double: 1. They permit a saving effect for other usual drugs in asthma; 2. They reinforce the other drugs action.

Asthma↗
PubMed1986

[The psychological universe of the asthmatic].

The very nature of asthmatic attacks is alarming. Waiting for an attack in itself creates anxiety. The unpredictable nature of the condition is also anxiety producing. However, this type of anxiety is not simple and the patient's attitude to it is often ambiguous. Asthmatic patients do not have a specific type of personality but a neurotic and psychosomatic context is common. By psychosomatic we mean reactional behaviour to the disease rather than "psychogenesis" of attacks, although emotional factors are often observed. Asthmatic patients do not live alone. They live in an environment which affects them and which is affected by them: a special psychodynamic relationship is set up, especially in young patients, and not to recognise it would be to ignore part of the patient and of the disease.

Adult↗
PubMed1985

[Alcohol and the lung. Anatomical and functional consequences].

The noxious effects of alcohol on the body are multiple. The lung is also a target organ in chronic alcoholic intoxication. The effects on the respiratory system may be divided into two groups: lowering of the defense functions of the respiratory system, especially to micro-organisms and a general depression of the immune system; decreased respiratory function sometimes associated with pronounced hypoxemia and decreased affinity of haemoglobin for oxygen especially during exercise. These patients have been shown to have an increased cardiac output, decreased pulmonary artery pressures and increased alveolar-capillary oxygen gradients, suggesting a porto-pulmonary shunt. From a practical point of view, hypoxemia in the alcoholic patients should not be misdiagnosed, since they can be functionally improved by domiciliary oxygen therapy.

Alcoholic Intoxication↗
PubMed1985

[Bromocriptine in Parkinson's disease: pleuropulmonary toxicity].

The authors report a case of pleuro-pulmonary fibrosis after 9 months of high dose bromocriptine therapy for the treatment of Parkinson's disease. When the drug was stopped there was a significant improvement of the clinical state with complete regression of chest pain and dyspnea of effort. The major inflammatory biological syndrome disappeared completely. Chest X-rays showed partial improvement with signs of pleural pneumonitis. The results of ventilatory and respiratory function tests stabilised. After one year follow-up, the causal relationship of this iatrogenic pathology has therefore been established. The initial diagnostic problems are stressed, particularly with respect to malignant disease (mesothelioma) when there has been exposure to asbestos, as in our case. The early stages must be carefully looked for so as to prevent fibrosing complications. The presence of immune complexes in our case could indicate immuno-allergic mechanism.

Bromocriptine↗
PubMed1984

[Pleuropulmonary fibrosis and bromocriptine].

From a personal case and a review of the literature, it is recalled that bromocriptine may induce pleuropulmonary fibrosis. The various presentations of this condition are described. The index patient is a 56-year-old man, with Parkinson disease and a negative history for respiratory disease, who was taking bromocriptine in a high dose (60 mg/d). Under this treatment, he exhibited weight loss and an inflammatory syndrome and developed interstitial pneumopathy with secondary pleuropulmonary fibrosis, which resolved in part once therapy was discontinued. Bromocriptine, which is an ergot alcaloid with dopaminergic properties, has been used since 1965 in therapy. Its indications, which at the outset were restricted to endocrinology, were extended in 1972 to Parkinson disease, with a significant increase in dosages from 1979. Its responsibility in pleuropulmonary fibroses was suspected in 1981 by Rinne on data from 5 patients. As of now, 8 cases have been reported. All are Parkinson patients who, after a variable time interval (15 days to 3 years), developed a uniform picture of pleuropulmonary disease with rapidly increasing dyspnea upon exertion and deterioration of general health. These features mirror inflammation then fibrosis of the pleura and lung tissue, which results in a variable degree of chronic restrictive respiratory failure. The course is equally uniform, with partial resolution under corticosteroid therapy and more or less significant residual fibrosis at discontinuation of treatment. Immunoallergic rather than toxic or vasomotor mechanisms seem involved.(ABSTRACT TRUNCATED AT 250 WORDS)

Bromocriptine↗
PubMed1984

Treatment of adult asthma: controlled double-blind clinical trial of oxitropium bromide.

Sixteen young adult sufferers from extrinsic paroxysmal asthma with pollen hypersensitivity took part in a therapeutic trial of the synthetic anticholinergic agent oxitropium bromide administered by a metered dose inhaler. The study comprised three 3-week periods. The first, run-in period was carried out to confirm the ability of the patients to maintain a daily record of symptoms. During the second and third periods, the patient received 3 X 2 inhalations of drug or placebo in a cross-over design. The medical staff was blind to the nature of the aerosol (drug or placebo), which was given in random order. The run-in clinical score was high. Asymptomatic days were relatively infrequent and daily drug consumption was high. Functional studies between the cross-over periods showed flow-rate values close to normal, with an increase in residual volume and functional residual capacity. During treatment either with placebo or oxitropium, there was a statistically significant decrease in clinical scores. Results for oxitropium bromide treatment were significantly better than the run-in values (p less than 0.005) and the placebo period (p less than 0.02). There was no significant change in non-trial drug consumption. Functional values showed no difference in terms of flow rate, although oxitropium did cause a significant improvement in the RV/TLC ratio (p less than 0.05). No adverse reactions were reported.

Administration, Intranasal↗