[Development of clinical trial education program for pharmaceutical science students through small group discussion and role-playing using protocol].

The acquirement of basic knowledge of clinical trials and professional attitude in their practices is a general instructional objective in the Model Core Curriculum for Pharmaceutical Education. Unfortunately, the previous program of clinical trial education was not effective in the acquirement of a professional attitude in their practices. Then, we developed the new clinical trial education program using protocol through small group discussion (SGD) and roll-playing. Our program consists of 7 steps of practical training. In step 1, the students find some problems after presentation of the protocol including case and prescription. In step 2, they analyse the extracted problems and share the information obtained in SGD. In steps 3 and 5, five clinical case scenarios are presented to the students and they discuss which case is suitable for entry to the clinical trial or which case corresponds to the discontinuance criteria in the present designed protocol. In steps 4 and 6, the roll-playing is performed by teachers and students as doctors and clinical research coordinators (CRC) respectively. Further, we conducted a trial practice based on this program for the students. In the student's self-evaluation into five grades, the average score of the skill acquisition level in each step was 3.8-4.7 grade. Our clinical trial education program could be effective in educating the candidates for CRC or clinical pharmacists.

Studies on interactions between functional foods or dietary supplements and medicines. I. Effects of Ginkgo biloba leaf extract on the pharmacokinetics of diltiazem in rats.

The effects of Ginkgo biloba leaf extract (GBE), one of the most widely used herbal dietary supplements in Japan, on the pharmacokinetics of diltiazem (DTZ), a typical probe of cytochrome P450 (CYP) 3A, were examined in rats. The simultaneous addition of GBE to small intestine and liver microsomes inhibited the formation of N-demethyl DTZ (MA), an active metabolite of DTZ produced by CYP3A, in a concentration-dependent manner, with an IC(50) of about 50 and 182 microg/ml, respectively. This inhibition appeared to be caused, at least in part, by a mechanism-based inhibition. Both the rate of formation of MA and total amount of CYP in intestinal or hepatic microsomes after a single oral pretreatment with GBE (20 mg/kg) decreased transiently. The pretreatment significantly decreased the terminal elimination rate constant and increased the mean residence time, after intravenous administration of DTZ (3 mg/kg). Furthermore, it significantly increased the area under the concentration-time curve and absolute bioavailability after oral administration of DTZ (30 mg/kg). These results indicated that the concomitant use of GBE in rats increased the bioavailability of DTZ by inhibiting both intestinal and hepatic metabolism, at least in part, via a mechanism-based inhibition for CYP3A.