Takumi Ochiai

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An improved method for the preparation of glycerinated Vorticella convallaria was investigated. The pretreatment of living vorticellas with a medium containing 0.1% saponins and subsequent treatment with an extraction medium containing 35% glycerol at about 0 degrees C was satisfactory. The equilibrium average length of contractile stalks of glycerinated(More)
We measured the activity of orotate phosphoribosyl transferase (OPRT), the amount of thymidylate synthase (TS) enzyme, and the activity of dihydropyrimidine dehydrogenase (DPD) for individual tissue types in order to study the contribution of these substances to the effects of the pyrimidine fluoride anticancer drug 5-fluorouracil (5-FU). We also studied(More)
The effect of gastrectomy on pharmacokinetics after S-1 administration was investigated in a total of 12 cases - nine in which partial gastrectomy was performed and three in which total gastrectomy was performed. A single oral dose of S-1, 50 mg as tegafur, was administered, serial peripheral blood samples were collected, and the concentrations of(More)
The drug sensitivity of tumor cells is one of key issues to explore individualized therapy for cancer patients. One of such methods is in vitro anticancer drug sensitivity test which is generally based on one drug concentration and contact time. In this study, 5-fluorouracil (5-FU) sensitivity of cancer cells from colorectal cancer patients was evaluated by(More)
Orotate phosphoribosyl transferase (OPRT) is the main enzyme that involves in phosphoribosylation of 5-fluorouracil (5-FU), an essential step that leads to tumor growth inhibition. In our study, the prognostic relevance of OPRT, thymidylate synthase (TS) and dihydropyrimidine dehydrogenase (DPD) in resectable colorectal cancer (CRC) patients treated by oral(More)
Orotate phosphoribosyl transferase (OPRT) is an enzyme playing an important role in exertion of the effect of 5-fluorouracil (5-FU). A type of gene polymorphism, single nucleotide polymorphism (SNP), is considered to be a factor affecting individual differences in exertion of drug effects, and its analysis has recently made progress. We investigated the(More)
We have previously reported the 5-fluorouracil (5-FU) sensitivity of cancer cells from colorectal cancer (CRC) patients using the collagen gel droplet embedded culture-drug sensitivity test (CD-DST) under multiple drug concentrations and contact durations. Moreover, the area under the concentration curve (AUC) and growth inhibition rate (IR) were combined,(More)
Recently, it was reported that the anticoagulant effect of warfarin was reduced when patients receiving warfarin also took menthol. The purpose of this study is to reveal the mechanism of this reduced anticoagulant effect of warfarin from the pharmacokinetic point of view. Warfarin was orally administered to mice 24h after the administration of menthol for(More)
The levels of OPRT, DPD, and TS were determined in colorectal cancer tissue specimens, and 5-FU sensitivity was measured by CD-DST. The correlation between enzyme activity and 5-FU sensitivity was then studied. Six patients with colorectal carcinoma who had undergone surgical resection in our institution between May and August 2000 were studied. The CD-DST(More)
3574 Background: Dihydropyrimidine dehydrogenase and thymidylate synthase are 5-FU metabolism and target enzyme, and has been studied as prognostic factors in CRC. Meanwhile, phosphoribosylation of 5-FU is an essential step leads to tumor growth inhibition and OPRT is the main enzyme that involves in this conversion of 5-FU to FUMP. The aim of this study(More)