Biomedical subjects

L Bertaux

Publications and source records attributed to L Bertaux.

7 recordsLinked to original sources

PubMed1993

Evoked potentials and cerebral blood flow in solvent induced psycho-organic syndrome.

Epidemiological studies have provided evidence that neuropsychiatric symptoms are induced by long term exposure to solvents; individual diagnosis with psychometric tests, however, is not always possible (for example, when the patient has linguistic difficulties). Therefore evoked potentials and cerebral blood flow were studied in 50 patients occupationally exposed to solvents who were referred to our department and for whom a solvent induced psycho-organic syndrome was suspected. Degree of exposure was evaluated by its duration (mean 13.9, range 1 to 37 years) and its intensity (from an interview). At the group level, P22 and N35 latencies and amplitude N20-P22 of somatosensory evoked potentials were higher in cases than in controls (p < 0.05), whereas there was no difference for brainstem and visual evoked potentials, nor for hemispheric cerebral blood flow (but a higher distribution in the left occipital region was seen in patients, p < 0.05). Some parameters were linked to degree of exposure (amplitude N20-P22 of somatosensory evoked potentials, interpeak latency I-V of brainstem evoked potentials, distribution of cerebral blood flow in the internal frontal left region). At the individual level, these examinations were not of diagnostic value because sensitivity was low.

Adult↗

PubMed1991

Enhancement of propoxyphene bioavailability by ethanol. Relation to psychomotor and cognitive function in healthy volunteers.

The interaction between a single oral dose of 130 mg propoxyphene and 0.5 g/kg body weight ethanol was investigated in 12 healthy male volunteers by 9 objective performance tests, 8 visual analogue self-rating scales and the measurement of plasma propoxyphene, norpropoxyphene and ethanol concentrations, using a double-blind threeway crossover design. Volunteers were each given one of three treatments, propoxyphene + ethanol, placebo + ethanol and propoxyphene alone, separated by a two week interval. The performance tests were completed before and 1.25 and 4 h after drug intake, and the self-rating scales before and 1.25, 4 and 10 h after it. Ethanol was shown to enhance the bioavailability of propoxyphene by 25% probably by reducing its first-pass metabolism. However, despite this pharmacokinetic effect no pharmacodynamic interaction was found. Subjective ratings disclosed that the effect of ethanol on physical and mental sedation predominated over the effects of propoxyphene.

Biological Availability↗

PubMed1991

Comparison of performance of healthy volunteers given prazepam alone or combined with ethanol. Relation to drug plasma concentrations.

The interaction between a single dose of 20 mg of prazepam and 0.5 g/kg body weight ethanol was investigated in 12 healthy male volunteers by nine objective performance tests, eight visual analogue self-rating scales and measurement of prazepam and ethanol plasma concentrations, using a double-blind three-way crossover design. The volunteers were each given three treatments (prazepam+ethanol, placebo+ethanol and prazepam alone), separated by a 2-week interval. They completed the performance tests before treatment and 1.5 and 4 h thereafter, and the self-rating scales before treatment, 1.5, 4 and 8 thereafter. To determine prazepam and ethanol plasma levels, venous blood samples were drawn before drug intake and 0.25, 0.5, 1, 1.5, 3, 4, 5 and 8 h thereafter. In two of the performance tests: auditory reaction time and digit symbol substitution, the combination of prazepam and ethanol was shown to impair performance more than either drug taken alone 1.5 h after their administration. A similar result was found for the drowsiness scored in the self-ratings. The time needed to complete the two-symbol cancellation test was longer when the subjects received prazepam either alone or combined with ethanol. Simultaneous ingestion of prazepam and ethanol did not alter the bioavailability of either drug.

Adolescent↗

PubMed1991

Comparative effects on psychomotor performance of the muscle relaxant afloqualone, alone and with ethanol.

The purpose of this study was to investigate the interaction between 40 mg afloqualone, a new centrally acting muscle relaxant and 0.5 g/kg ethanol using a double-blind three-way cross-over trial in which subjects were each given afloqualone with ethanol, ethanol alone and afloqualone alone. We first compared the effects of 40 mg oral afloqualone and 15 mg diazepam (considered as a reference drug) on the psychomotor and cognitive performance and muscular relaxation of 12 healthy male volunteers. Performance was assessed by six objective tests and eight visual analogue self-rating scales. All the above treatments were separated by a 2-week interval. Volunteers performed the objective tests 1 h after drug ingestion, and the self-rating scale evaluations before drug intake and 1, 3.5, 6 and 8 h thereafter. Afloqualone impaired psychomotor performance less than diazepam as shown by the number of correct answers in the digit symbol cancellation test and the time needed to complete this test. However, the measurement of the frontalis muscle action potential showed that the muscle relaxant activity of 40 mg afloqualone was equivalent to that of 15 mg diazepam. Furthermore, afloqualone given at an effective relaxant dose did not enhance the effects of a single dose of ethanol which predominated on either psychomotor performance or subjective feelings.

Administration, Oral↗

PubMed1990

Comparison of the effect of two prazepam formulations on psychomotor and cognitive function in healthy volunteers.

A double-blind crossover design was used to evaluate the effect of two different formulations of prazepam, on motor and cognitive functions and subjective symptoms. Ten healthy male volunteers received 20 mg of prazepam both in tablet and liquid (as drops) formulation, separated by a 1 week interval. All subjects completed a battery of 9 performance tests 2.25 h and 4.75 h after drug intake (corresponding to the times of peak plasma concentration). They also rated themselves on eight visual analogue scales before, 2 h, 4.5 h and 8 h following drug intake. A significant difference between liquid drops and tablets was demonstrated in 4 of the 9 performance tests and 2 of the 8 items of the self rating scales. These results suggest that a single dose of prazepam administered in liquid drop form exhibits greater sedative properties than the same dose administered as tablets in healthy volunteers, probably as a result of more rapid absorption.

Chemistry, Pharmaceutical↗

PubMed1987

[Not Available].

Explore the source record for details and available documents.

Forensic Medicine↗

PubMed1985

[Arsenous anhydride poisoning. Peripheral neuropathy and changes in cognitive functions].

The authors report the evolution over an 11 months period of a case of subacute intoxication with arsenic in a 30 years old woman. In addition to the classical peripheral neuropathy, we observed impairment of the superior neurological functions which improved together with the neuropathy. These malfunctions are rarely described in the literature although arsenic seems to cross the blood-brain barrier easily. There is no other explanation, and we believe arsenic to be responsible for these disturbances. We suggest systematic testing of the superior neurological functions in cases of arsenic intoxication.

Adult↗