PubMed Health⌕ Search

Biomedical subjects

B Lucas

Publications and source records attributed to B Lucas.

At least 109 records · Page 6Linked to original sources
PubMed1985

[Plasma renin activity and prostaglandin E2 in hypotension induced by nicergoline].

The hypotensive actions of nicergoline, a new alpha 1-adrenoreceptor blocking agent, were studied in six dogs during stable anaesthesia under mechanical ventilation. Systemic haemodynamic parameters were measured before the infusion of nicergoline (500 micrograms X kg-1 in 5 min), and regularly after it during 2 h. Plasma renin activity (PRA), right atrial (V PGE2) and arterial (A PGE2) prostaglandin E2 concentrations measured by radio-immunoassay were collected before, and 10 and 20 min after nicergoline infusion. The mean aortic pressure fell to its lowest figure (-30%) at the 5th min, this being maintained for 45 min. Heart rate and cardiac output remained unchanged. Pulmonary wedge pressure (p less than 0.01) and central venous pressure (p less than 0.05) decreased. All parameters reached their control values in 120 min. PRA was unchanged. V PGE2 (p less than 0.01) and pulmonary extraction in PGE2 (V PGE2 - A PGE2/V PGE2) (p less than 0,05) increased whilst A PGE2 was unmodified. The fall in mean aortic pressure was linked (p less than 0.001) to the increase in V PGE2. Nicergoline infusion induced hypotension by reducing vascular tone of resistance and capacitance beds. Hypotension was related to the vasoplegia and to an inhibition of the rapid pressor control mechanisms. The reasons for the lack of renin release were unknown. V PGE2 release was stimulated by the hypotension. The increase in pulmonary extraction in PGE2 was involved in the maintenance of A PGE2 concentration. Nicergoline gave mild hypotension without reflex sympathetic activation. Its alpha-adrenoreceptor blocking properties were similar to those of prazosin.(ABSTRACT TRUNCATED AT 250 WORDS)

Anesthesia, General↗
PubMed1985

[Plasma renin activity and prostaglandin E2 in hypotension induced by sodium nitroprusside].

Sodium nitroprusside (SNP) is a potent, effective and readily reversible vasodilating agent frequently used in anaesthesia for deliberate hypotension. Moderate hypotension induced by SNP activated catecholamine and vasopressin secretions, and the renin-angiotensin system, resulting in partial antagonism of the hypotensive response to SNP. Furthermore, this increase in renin release was involved in the hypertensive rebound after SNP withdrawal. This activation of vasoconstrictor systems led to pharmacological associations aimed at reducing the risk of cyanide poisoning. The physiological interrelationship between prostaglandins and renin secretion has now been well established but, as far as we know, no paper existed concerning prostaglandins during SNP-induced hypotension. In such hypotension (Pa: -30%), monitored by invasive and non invasive haemodynamic techniques (pulsed Doppler), the variations in plasma renin activity (PRA) and in venous and arterial plasma PGE2 concentrations (V PGE2 and A PGE2), determined by radioimmunoassay, were studied in anaesthetized dogs. Invasive haemodynamic data were similar to previous reports. Common carotid diameter increased (p less than 0.05), with a constant common carotid blood flow. PRA (p less than 0.05), V PGE2 (p less than 0.05) and A PGE2 (p less than 0.05) increased. PRA and V PGE2 were highly correlated before and after SNP. SNP resulted in hypotension with reflex sympathetic activation and dilatation of large arteries. Carotid blood flow autoregulation was maintained. Whilst pulmonary removal of PGE2 remained unchanged, an increase in A PGE2 may have been involved in the vasodilator mechanisms.

Animals↗
PubMed1985

Sustained ventricular unloading action of the alpha-adrenergic antagonist nicergoline in the dog.

Preliminary studies indicate that nicergoline, a new alpha-antagonist, can lower HR at doses which decrease arterial BP. The present animal study was designed to quantitate the systemic and carotid (pulsed Doppler) hemodynamic and renin release consequences of nicergoline ventricular unloading, and to investigate the hemodynamic mechanisms of hypotension. In 11 anesthetized dogs, nicergoline infusion induced progressive, moderate, and prolonged hypotension associated with reduced vascular resistance and capacitance. Hypotension resulted from decreased HR and cardiac output, without an increase in plasma renin activity. The effects on carotid hemodynamics were less marked than those on the systemic circulation. Hypotension was caused primarily by vasoplegia, and was magnified subsequently by inhibition of the reflex rapid pressor control mechanisms. This suggests that repeated iv doses of nicergoline are preferable to prolonged infusion.

Animals↗
PubMed1984

A successful physician marketing program.

Cardinal Glennon Memorial Hospital for Children in St. Louis is the site of an active and successful physician marketing program. Through two specific programs, one directed at private physicians on staff and the other at referring physicians outside of St. Louis, Glennon has realized many benefits, including increased utilization. Glennon's marketing program and specific marketing techniques are detailed here.

Hospital Bed Capacity, 100 to 299↗
PubMed1984

Systemic and carotid haemodynamics and plasma renin activity during deliberate hypotension in dogs: a comparison of sodium nitroprusside with nicergoline.

This study was designed to compare at the same level of hypotension (-30%) nitroprusside (SNP) and nicergoline (NIC) effects on systemic haemodynamics and carotid haemodynamics (pulsed Doppler) and on plasma renin activity (PRA) in 20 anaesthetized dogs before and at the 20th minute of hypotension. In SNP group (n = 9) cardiac output (CO) and heart rate (HR) increased. Stroke volume (SV), pulmonary wedge pressure (PWP), central venous pressure (CVP) and systemic vascular resistance (SVR) decreased. Common carotid diameter (D) increased and blood flow velocity (V) decreased with constant common carotid blood flow (CCBF). CCBF/CO ratio was unchanged. PRA levels increased. In NIC group (n = II), HR, CO, SV were unchanged and PWP, CVP, SVR decreased. D, V and CCBF were unchanged. CCBF/CO ratio increased and PRA was unchanged. NIC provoked mild hypotension without reflex sympathetic activation unlike SNP. Only SNP dilated large arteries. The autoregulation of CCBF is maintained with both drugs but CCBF/CO ratio is increased only with NIC.

Anesthesia↗
PubMed1983

[Paroxysmal nocturnal activity in partial epilepsy in the adult].

Thirty-four adults with partial epilepsy underwent polysomnographic sessions. Three sub-groups of patients were determined by timing their EEG paroxysmal activities (PA) according to the possible increase in PA related to their sleeping or awake state. Twenty-seven had an increase in PA when sleeping, 5 when awake and no significant difference was found in two other patients. Patients who suffered from nocturnal or partial elementary epileptic seizures were those who showed a PA increase when in a sleep state. These patients had a lower PA density during a waking state than the patients with a PA increase when awake. The more synchronized (stages 3 + 4) and desynchronized (waking) cortical states influence the PA densities in such a way that there is a significant difference between both sub-groups. The PA density modulation found with the slow-wave sleep stages adds to that induced by sleep and waking states.

Adolescent↗
PubMed1981

[Acquired aphasia in epileptic children--four cases with electrical infraclinic status epilepticus during sleep (author's transl)].

Four cases of acquired aphasia in epileptic children, associated with sub-continuous bitemporal paroxysmal activities (PA) during sleep, are described. Clinical improvement always followed the decrease or the unilateralization of PA. Persistence or aggravation of aphasia was observed when PA again became bitemporal and sub-continuous. Electroencephalographic characteristics of PA during sleep stages are described. Relationships of these cases with the 'sub-clinical electrical status epilepticus induced by sleep' and the physiopathology of aphasia are discussed.

Aphasia↗
PubMed1981

Effect of salbutamol, a putative cerebral beta agonist on sleep stages and interictal epileptic discharges.

The effects of Salbutamol 1.5 mg in 250 ml dextrose solution was tested on 14 epileptic patients following a double blind cross-over design. Sleep parameters and interictal paroxysmal activities density were measured. No seizures were encountered during the experiment. No modification of either sleep parameters (duration of sleep stages, latency of sleep and paradoxical sleep, duration of sleep cycles and awaking) or density of P. A. during waking state, on stage I, II, III and IV and paradoxical sleep were observed. In other respects, 5 patients had no P. A. during polygraphic sessions. They exhibited a longer duration of paradoxical sleep and a shorter duration of awaking than the 9 other patients with P. A. So with the dosage used here no implication of central beta-adrenoceptors in sleep mechanisms and production of epileptic activity are suggested.

Albuterol↗
PubMed1980

Adrenocortical function in idiopathic haemochromatosis.

In idiopathic haemochromatosis, excessive iron deposits include adrenal cortex, and mainly the zona glomerulosa. In this view, we measured basal and post-stimulative values of plasma cortisol, aldosterone and renin activity (RA) in two groups of patients: 1) 9 normal-salt repleted subjects (NSR) who were subjected to iv ACTH and furosemide tests, 2) 10 patients who were subjected to chronic salt depletion (CSD), to iv ACTH and furosemide tests. The results were compared with two groups of 7 healthy volunteers (NSR and CSD). In the patients, basal cortisol values were either normal or increased in cases of poorly controlled diabetes (21 +/- 2.1 microgram/100 ml, P < 0.01) and cortisol increase after ACTH injection was normal (to 43.3 +/- 4.3 microgram/100 ml). In the 9 NSR patients, basal aldosterone (7.75 +/- 1.5 ng/100 ml) and RA (1.55 +/- 0.27 ng/ml/h) values were normal; aldosterone and RA rose after furosemide injection: these increases were similar in these patients (respectively to: 13.5 +/- 2.2 ng/100 ml and 4.3 +/- 0.6 ng/ml/h) and in the 7 NSR controls. In the 10 CSD patients, basal aldosterone and RA values were always increased (26.5 +/- 3.2 ng/100 ml and 8.5 +/- 2.3 ng/ml/h) as much as in the 7 CSD controls. After ACTH administration, aldosterone values (26.1 +/- 4 in NSR patients, 54 +/- 8 ng/100 ml in CSD patients) were the same as in the two control groups. This study suggests that there is no adrenocortical deficiency in idiopathic haemochromatosis, in spite of excessive iron deposits in the adrenal cortex.

Adrenal Cortex↗
PubMed1977

Nutrient intake and stimulant drugs in hyperactive children.

Recent studies have demonstrated suppressed growth of height and weight in children receiving stimulant drugs for hyperactivity. For approximately twelve months, growth data and food records were collected on two subjects receiving different types and dosages of stimulant drugs. The two cases demonstrated that dextroamphetamine levels of 10 mg. or more and methylphenidate levels of 30 mg. or more decreased caloric intake significantly. This decrease may be limiting for long-term growth. Both subjects had a variety of feeding problems due to poor appetite. Careful nutritional evaluation and planning are important to insure optimal energy and nutrient intake in these children receiving stimulant drugs.

Ascorbic Acid↗
PubMed1976

Multichambered bladder anomalies.

This report reviews multichambered bladder conditions, offers a workable classification of them, presents a detailed case report, and discusses the possible causes of these anomalies. We wish to stress the importance of careful examination of the genital area in the newborn and early roentgenologic evaluation of the genito-urinary system when an anomaly is found.

Diverticulum↗
PubMed1976

Prevalence of hypertension in a renal transplant population on alternate-day steroid therapy.

A study of the prevalence of hypertension in a group of renal transplant patients on alternate-day maintenance steroid therapy was conducted. Twenty-four percent of the transplant clinic population was hypertensive. The factors that were associated with a lower prevalence of hypertension were good graft function, bilateral nephrectomy of the patients' own diseased kidneys (although the majority of our patients without bilateral nephrectomy are normotensive), and use of a living related donor. We conclude that the prevalance of hypertension in transplant patients on alternate-day steroid therapy is low. In the presence of all these favorable factors, only 6% of allograft recipients were hypertensive.

Adolescent↗