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J C Evreux

Publications and source records attributed to J C Evreux.

At least 19 recordsLinked to original sources

Fluoride salts are no better at preventing new vertebral fractures than calcium-vitamin D in postmenopausal osteoporosis: the FAVOStudy.

Although fluoride salts have been shown to be capable of linearly increasing spinal bone mineral density (BMD) in postmenopausal osteoporosis, the effects of this gain in density on the vertebral fracture rate remain controversial. We conducted a 2-year multicenter, prospective, randomized, double-masked clinical trial in 354 osteoporotic women with vertebral fractures (mean age 65.7 years). They received either fluoride (208 patients), given as sodium fluoride (50 mg/day) or as monofluorophosphate (200 mg/day or 150 mg/day), or a placebo (146 patients). All patients received daily supplements of 1 g of calcium (Ca) and 800 IU of vitamin D2 (D). A 1-year open follow-up on Ca-D was obtained in 124 patients. After 2 years the fluoride group and the Ca-D group had increased their lumbar BMD by 10.8% and 2.4% respectively (p = 0.0001). However, the rate of patients with at least one new vertebral fracture, defined by semiquantitative assessment and evaluable on an intention-to-treat basis in 89% of patients, was similar in the fluoride groups and the Ca-D group. No difference between the three fluoride regimens was found. The percentage of patients with nonvertebral fractures was not different in the fluoride and Ca-D groups (1.9% and 1.4% respectively for hip fractures). A lower limb pain syndrome occurred more frequently in the fluoride groups. In the 124 patients followed for 1 year after cessation of fluoride therapy, the percentage of patients with at least one new vertebral fracture after 36 months was identical to the percentages in the previous fluoride group and the Ca-D group. We conclude that fluoride-Ca-D regimen was no more effective that Ca-D supplements for the prevention of new vertebral fractures in women with postmenopausal osteoporosis.

Aged↗

[Drug-induced fever caused by hydroxyurea. Apropos of 3 new cases].

Drug-induced fever is a frequent (3-5% of all adverse effects) but under recognized adverse effect of several drugs. Hydroxyurea, an antimetabolite cytostatic agent, has rarely been involved in the occurrence of fever. We report three additional cases of hydroxyurea-induced fever including one case with pulmonary involvement (acute alveolitis). In these cases, the role of hydroxyurea was strongly suggested by the delay to onset of symptoms (16-36 days), the disappearance of fever within a few hours after drug withdrawal, the recurrence of fever shortly after rechallenge in two patients, and the absence of any other obvious cause.

Aged↗

[Cardiac accidents of locoregional anesthesia: experimental study of risk factors with bupivacaine].

Cardiac disorders are observed when excessive plasma concentrations of local anaesthetics are reached, following for instance intravascular accidental injection for epidural anaesthesia or brachial plexus block. Bupivacaine particularly, which is one of the most used local anaesthetics, adversely affects intraventricular conduction and cardiac contractile strength from the 3.0-4.0 micrograms/ml blood levels. Depression of conduction is especially to be feared, for it can result in reentrant arrhythmias likely to degenerate into often fatal ventricular fibrillation. Such accidents may sometimes occur at far lower concentrations, subsequent to diffusion into systemic circulation from the injection site (0.4-1.2 micrograms/ml). These accidents were probably due to various factors which concomitantly intervene during the anaesthesia. We could identify a number of these factors by associating them to an intravenous infusion of bupivacaine (0.04 mg/kg/min after a loading dose of 1.00 mg/kg) in animals (dogs and pigs) under electrocardiographic monitoring, in which conduction time, monophasic action potential duration, effective refractory period and electrical fibrillation threshold were determined in the ventricular fibres. The electrophysiological changes due to bupivacaine may be enhanced by 1) dilution hyponatremia (115-110 mmol/l) induced by a short (5 min) intravenous 10 ml/kg/min infusion of hypotonic solution and/or hyperkalemia (7-8 mmol/l) induced by 0.05 mmol/kg/min infusion of potassium chloride; 2) the acceleration of cardiac contractions (180-210 beats/min) induced by ventricular pacing; 3) mild hypothermia (35-34 degrees C) induced by blood cooling in an extracorporeal circuit; 4) myocardial ischaemia induced by complete temporary occlusion of the left anterior descending coronary artery near its origin. The risk of cardiac accidents, possibly severe, is therefore enhanced by each of these factors capable of lowering the concentration required for their triggering and, of course, the combination of two or several of them. On the contrary, the knowledge of these factors should allow to prevent most of cardiac accidents of locoregional anaesthesia.

Accidents↗

Calcium antagonists and prevention of ventricular fibrillation induced by transient or persistent ischemia.

Experimental studies have shown the limitation by calcium antagonists of the propensity to fibrillation secondary to the occlusion of a large coronary artery. However, this capacity, studied in the acute phase of infarction, is less obvious and still under debate. Ischemia was therefore produced in anesthetized, open-chest pigs by complete occlusion of the left anterior descending coronary artery according to two modes, either near its origin during brief but increasing periods (30, 60, 120, 180 s, etc) or half-way from this origin for a much longer time (60 min). The time course of vulnerability to fibrillation was monitored by ventricular fibrillation threshold (VFT), measured by trains of diastolic stimuli of 100 ms. Verapamil was administered in a 50 micrograms/kg dose followed by 2 micrograms/kg/min infusion. 1) In the case of brief proximal occlusions under pacing at a constant high rate (180 beats/min), verapamil slowed the decline of VFT from 6-8 mA to nearly 0 mA. VFT was 4.4 +/- 0.4 mA after 60 s ischemia, whereas it had already fallen to 1.8 +/- 0.3 mA (p < 0.001) in the absence of the drug. Accordingly, the onset of spontaneous fibrillation which depends on the decrease in VFT to about 0 mA was prolonged from 2-3 to 6-9 min. Bradycardia, concurrently produced by verapamil, is a factor which enhances these alterations. 2) In the case of a persistent midportion occlusion of the artery under sinus rate, fibrillations were similarly delayed by verapamil from 14-25 to 23-49 min after occlusion, but they were more numerous. VFT was lowered to critical values later, but also for a longer time. The period propitious to fibrillation was prolonged because the return of VFT to higher values reflecting hypoexcitability subsequent to the first cell injury was substantially delayed. Consequently, calcium antagonists should often prevent ventricular fibrillation when transient ischemia disappears before VFT falls to the vicinity of 0 mA. In contrast, a real benefit could not be expected from these drugs when ischemia is persistent since they then only delay fibrillations, the number of which is increased.

Analysis of Variance↗

[Exacerbation of myasthenia gravis by pefloxacin].

Pefloxacine 800 mg single dose was given as routine treatment after a cystomanometric examination to a 45-year-old woman with a 30-month history of generalized myasthenia gravis. One hour after, the patient developed exacerbation of myasthenia gravis with bilateral ptosis and an increased generalized weakness. She experienced a rapid improvement during the next 8 hours and physical examination returned to normal within one day. No additional factors which might have contributed to the exacerbation of myasthenia gravis were found. The report of exacerbation of myasthenia gravis with other antibiotic belonging to the group of fluoroquinolones (ciprofloxacin, norfloxacin and ofloxacin) prompt us to recommend caution with the use of all fluoroquinolones in myasthenic patients.

Anti-Infective Agents↗

[Hypoglycemia induced by oral hypoglycemic agents. Records of the French Regional Pharmacovigilance Centers 1985-1990].

All 98 cases of sulfonylurea-induced hypoglycemia reported by the 30 regional drug-monitoring centers between 1985 and 1990 were analyzed: 46 with gliclazide, 40 with glibenclamide, 5 with glipizide, 1 with glibornuride and 6 with first-generation sulfonylureas. These cases of hypoglycemia were often serious. The patients were 61% female and their mean age was 78.9 years. The average number of medications being taken was 3.4, but ranged up to 14. The risk factors were: reduced food intake (4.2%), renal failure (4.2%), prescription error (3.2%), voluntary or accidental overdose (5.2%), alcohol (1.1%), suspected drug interactions (50%), unknown (32.6%). The most frequent drug interactions involved miconazole (8 cases), angiotensin-converting enzyme inhibitors (9 cases), lipid-regulating agents (fibrates) (7 cases), co-trimoxazole (trimethoprim-sulfamethoxazole; 5 cases), metformin (4 cases), histamine H2-receptor antagonists (4 cases). The mechanisms of these interactions are discussed.

Administration, Oral↗

[Retroperitoneal fibrosis with eye-drops containing timolol].

Retroperitoneal fibrosis occurred in a 62-year-old man who had been treated during 4 years eye-drops containing timolol. The disease was diagnosed after a sudden episode of nephritic colic. The recovery was progressive and uneventful. No corticosteroid therapy was used. Six months later the patient remained free of symptoms. Although an idiopathic origin could not be excluded, the causal relationship with timolol treatment is likely due to the chronology of events and the lack of other causes.

Colic↗

Spiramycin: safety in man.

Spiramycin, a 16-membered lactone ring macrolide, has been in clinical use for the past 15 years with little serious associated toxicity. Gastrointestinal disturbance has usually been mild and no changes in gastrointestinal motility have been noted either experimentally or in humans, in contrast to other macrolides, such as erythromycin. Allergic reactions have been uncommon and mainly restricted to transient skin eruptions. Although liver injury is a possible complication of most macrolide treatments, no conclusive evidence for spiramycin-induced hepatitis is currently available, and, again in contrast to most other macrolides, the lack of drug interactions with spiramycin has been clearly established in biochemical, pharmacokinetic and clinical studies.

Humans↗

Enhancement of antibody response and delayed-type hypersensitivity by thalidomide in mice.

Renewed interest in thalidomide stemmed from the suggestion by several authors that it might prove useful against immune-related diseases. Despite interesting preliminary findings, little is actually known regarding its immunoenhancing properties in vivo. Male and female Swiss mice, aged 6-8 wk, were given 0.5 or 25 mg/kg/day of thalidomide orally for 4 wk. Various immunological parameters were then assessed. When compared to controls, mice exposed to the higher dose presented with a significantly increased thymus weight index, whereas spleen weight index remained unchanged. Anti-sheep erythrocyte plaque-forming cells and hemagglutinin titers were increased by 44% and 29%, respectively. Contact hypersensitivity to picryl chloride was enhanced by 62%. Finally, colloidal carbon clearance was not altered. Interestingly, the lower dose (5 mg/kg/day) exerted no effect whatsoever.

Animals↗

Influence of tetanus and typhoid vaccines on hepatic drug metabolism.

Several experiments suggested that vaccines might inhibit liver drug-metabolizing enzymes, an assumption in agreement with other findings obtained with most immuno-enhancing agents. A direct, non-specific activation of macrophages with subsequent release of interleukin 1 may account for this inhibition. The purpose of the present study was to investigate whether tetanus and typhoid vaccines exerted such an influence on pentobarbital sleeping time in mice and antipyrine elimination in rabbits, both in vivo correlates of the activity of these enzymes. It is shown that tetanus (unlike typhoid) vaccination in both species can lead to a marked but transient impairment of hepatic drug metabolism in these conditions. The reason for this discrepancy is unclear. The assumption that aluminium hydroxide might play a critical role, as this adjuvant is included in the formulation of tetanus vaccine in contrast to that of typhoid vaccine, is not supported by our findings since aluminium hydroxide alone failed to exert any influence in our experimental conditions. Further studies are therefore warranted to elucidate the mechanism of this inhibition of the activity of hepatic drug-metabolizing enzymes.

Aluminum Hydroxide↗