[Adjusting the dosage of netilmicin from two measurements. Program validation]. / Adaptation des posologies de la nétilmicine à partir de deux points. Validation d'un programme.

The aim of this study is to give to clinicians a well validated usefull tool allowing an increase of safety in the monitoring of netilmicin. During the first administration of the drug, two plasmatic concentrations are measured, and input in a preprogrammed hand-held calculator. A posology and a rythm of administration are returned by the calculator. After six days of this dosage regiment, the peak and the valley concentrations are compared with those previously given by the computer as values at equilibrium. No significant difference can be observed. There is no change in plasmatic creatinine level from the first to the sixth day of treatment. So, a preprogrammed hand-held computer can be convenient and safe to monitor netilmicin.

Comparison of caffeine metabolism by slices, microsomes and hepatocyte cultures from adult human liver.

1. Caffeine was used as a molecular probe for hepatic monooxygenase activity in three in vitro models from human livers: slices, microsomes and hepatocyte cultures. 2. A h.p.l.c. method for determination of all possible metabolites of caffeine (16 compounds) is described. 3. Caffeine biotransformation by these three in vitro systems was low. However, metabolite formation was shown to proceed at a rate close to that calculated from in vivo caffeine elimination half-life. 4. Metabolic profiles were the same whatever the in vitro system used. The ratio of primary demethylated metabolites was similar to that measured by in vivo studies, i.e. the selectivity for caffeine N-3 demethylation to paraxanthine was retained. 5. Significant correlation (p less than 0.001) between 7-ethoxyresorufin O-deethylation and caffeine demethylations was demonstrated for the 12 human livers studied.