PubMed Health⌕ Search

Biomedical subjects

R Elie

Publications and source records attributed to R Elie.

108 records · Page 6Linked to original sources
PubMedDate not supplied

Butriptyline: human pharmacokinetics and comparative bioavailability of conventional and sustained release formulations.

The pharmacokinetics and relative bioavailability of butriptyline from conventional and a sustained release (SR) formulation have been studied in a panel of 14 volunteers. A single oral dose of 75 mg butriptyline hydrochloride was administered and a 2 X 2 latin square design was followed. Pharmacokinetic modelling has shown that the plasma butriptyline concentration/time profile is adequately described by a two-compartment open model; good agreement was obtained for the model-fitted and measured parameters. The SR formulation was shown to possess sustained release characteristics as evidenced by the increase in Tmax for 2.6 to 7.5 h, the decrease in Cmax from 46.5 to 10.3 ng ml-1, and a three-fold increase in 'half-value duration' (HVD). The changes have been achieved without any significant decrease in the relative bioavailability of the SR formulation. The half-life of butriptyline in plasma was about 20 h and was not formulation dependent.

Adult↗
PubMedDate not supplied

Electron-capture gas chromatographic determination of loprazolam in plasma and a pharmacokinetic application.

A sensitive and specific gas chromatographic method, using an electron capture detector, for the measurement of plasma concentrations of loprazolam (HR-158) is described. Retention times of the hydrolysis product of loprazolam (2-amino-2'-chloro-5-nitrobenzophenone) and of the internal standard (2-amino-2'-fluorobenzophenone) were, respectively, 9 and 7 minutes. The sensitivity of the assay was 1.0 ng ml-1 of plasma, and for drug concentrations ranging from 1.0 to 15 ng ml-1 the mean recovery from plasma was 94.4 per cent and the mean coefficient of variation 9.8 per cent. This method was used to determine some pharmacokinetic parameters of loprazolam after administration of 2 X 1 mg capsule doses to nine healthy, fasted volunteers. The mean t 1/2 was 6.4 h, mean AUC infinity 65.42 ng.h ml-1, and the mean clearance 0.51 l min-1.

Adult↗
PubMedDate not supplied

Comparative biopharmaceutical performance of imipramine formulations in man.

The systemic availability of an investigational liquid formulation of imipramine was compared to that of a commercially available tablet (Tofranil) whose therapeutic efficacy has been established by usage. The experiment was conducted under controlled conditions and a balanced 2-by-2 crossover design was used to dissociate the significance of formulation effects from subject, group, and experimental period sources of variation. Pharmacokinetic interpretation and statistical analysis of plasma concentrations as a function of time and of systemic availability indicators reveal a nearly identical biopharmaceutical behavior for the two preparations. Significant differences (P less than 0.05) were found in the cumulative area under the plasma concentration--time curve (AUC) up to 4 hours after administration and the availability lag time, but not in the maximum plasma concentration, the time at which this concentration is reached, the first-order availability rate constant, and the AUC to infinity. These results collectively indicate a very similar biopharmaceutical performance, where the differences in the early AUC values are partly attributable to a longer availability lag time for the tablet formulation.

Adult↗
PubMedDate not supplied

Psychological distress and adaptational problems associated with discontinuation of benzodiazepines.

This study compared subjects who had received standard tapered withdrawal of benzodiazepine (BZD) (group 1) with a group with comparable diagnosis still receiving BZD (group 2) and a control group of comparable diagnosis not yet receiving treatment (group 3). Sixty subjects aged 21-65 years with a diagnosis of nonpsychotic anxiety or insomnia were included. The assessment of psychological distress and quality of life was timed to coincide with the maximum immediate effect of BZD discontinuation, as calculated according to drug half-life. Subjects diagnosed with insomnia reported lower distress in all three groups. The pattern of distress experienced by group 1 was closer to group 3 than to group 2, indicating the potential importance of re-emergence of anxiety. High neuroticism, lower education level, and lower quality of life were associated with higher levels of distress during withdrawal.

Adaptation, Psychological↗
PubMedDate not supplied

[Role of adherent cells in GVH induced immunosuppression].

Two different mechanisms seem to be involved. In early GVH there is apparently an amplification of a normal inhibitory function of a cells. In more advanced GVH immunosuppression seem to be caused by a GVH induced suppressive activity of A cells. Both activities seem to be mediated by soluble factors.

Animals↗
PubMedDate not supplied

[Neurobiology in panic states].

Research in panic disorder (PD) has highlighted a low biological threshold (lactate infusion). Also, several studies have shown neurophysiological changes with PD patients: increased brain perfusion (Stewart), parahypocampal hyper-perfusion (Reiman) and we reported an increased incidence of epileptiform abnormalities. In order to assess neuroanatomical changes we carried out a study with magnetic resonance imaging (MRI) of P.D. as compared to controls. A prospective study with MRI was done with 13 P.D. patients and 10 controls. The inclusion criteria were outpatients with P.D. according to DSM-III criteria. All subjects (patients and controls) were right handed and between 18 and 40 years of age. Usual exclusion criteria were used. A Signa MR machine of 1.5 telsa (General Electric) was used and images in T1, T2 mode were generated. We found a higher percentage of brain atrophy in patients with PD (64%) than with controls (20%) and the differences reached significance (p-.04-Fisher ex. test). Right temporal lobe horn atrophy was the most common finding in P.D. patients. There were no difference between patients and controls for age, sex and weight. We have found anatomical changes in young P.D. patients. Whether this atrophy found with MRI and physiological changes previously reported are related should assessed further. However, our findings support biological factors in the etiology of PD and stimulates the development of better pharmacological treatments.

Adolescent↗