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H Eda

Publications and source records attributed to H Eda.

28 records · Page 2Linked to original sources
PubMed1990

Comparative antitumor activity and intestinal toxicity of 5'-deoxy-5-fluorouridine and its prodrug trimethoxybenzoyl-5'-deoxy-5-fluorocytidine.

N4-Trimethoxybenzoyl-5'-deoxy-5-fluorocytidine (Ro 09-1390), a prodrug of the cytostatic 5'-deoxy-5-fluorouridine (5'-DFUR), was synthesized with the aim of reducing of the dose-limiting toxicity of 5'-DFUR, which is diarrhea. In mice bearing Lewis lung carcinoma, 5'-DFUR given po produced a substantial amount of 5-fluorouracil (5-FU) in the intestinal tract as well as tumors, where the enzyme pyrimidine nucleoside phosphorylase, essential for conversion of 5'-DFUR to 5-FU, is predominantly located. With the oral administration of Ro 09-1390 only a small amount of 5-FU was formed in the intestine; however, the administration of Ro 09-1390 and 5'-DFUR at the same dose produced similar amounts of 5-FU in tumor tissues. These differences in metabolism were reflected in their toxicity and antitumor efficacy. The administration of 5'-DFUR resulted in damage to the intestinal mucosal membrane and diarrhea in normal mice, whereas Ro 09-1390 was much less toxic to the intestinal tract. As regards antitumor activity, Ro 09-1390 and 5'-DFUR at equivalent doses inhibited the growth of Lewis lung carcinoma to similar extents. Since Ro 09-1390 was much less toxic to the intestinal tract than 5'-DFUR, mice bearing Lewis lung carcinoma could be given Ro 09-1390 daily over a longer period and at a higher dose, resulting in a longer survival time.

Animals↗
PubMed1990

Comparative studies on the antitumor and immunosuppressive effects of the new fluorouracil derivative N4-trimethoxybenzoyl-5'-deoxy-5-fluorocytidine and its parent drug 5'-deoxy-5-fluorouridine.

N4-Trimethoxybenzoyl-5'-deoxy-5-fluorocytidine (Ro 09-1390), a new prodrug of 5'-deoxy-5-fluorouridine (5'-dFUrd), was synthesized for the purpose of finding a drug with less intestinal toxicity than the parent compound. The present study compared the antitumor activity and immunotoxicity of Ro 09-1390 with those of 5'-dFUrd, 5-fluorouracil (5-FUra) and tegafur in various transplantable tumor models. The antitumor efficacy of Ro 09-1390 was comparable to 5'-dFUrd and these two agents were much more effective than the others. However, Ro 09-1390 was much less toxic to the intestinal tract and less immunosuppressive in both humoral and cellular immune reactions than 5'-dFUrd. Consequently, Ro 09-1390 showed higher therapeutic indices and higher efficacy than 5'-dFUrd at high dosages. The antitumor spectrum of Ro 09-1390 was somewhat different from that of 5'-dFUrd, though it shows the efficacy after it converts to 5'-dFUrd. The activity of Ro 09-1390 was partly associated with cytidine deaminase in the tumors treated. Ro 09-1390 appeared to be more effective against tumors with a high concentration of the enzyme by which the major metabolite 5'-deoxy-5-fluorocytidine (5'-dFCyd) is metabolized to 5'-dFUrd.

Animals↗
PubMed1989

New instrument for monitoring hemoglobin oxygenation.

A new compact high-performance instrument for monitoring the oxygenation state of the human newborn are developed. First we applied this instrument to the rat head, and next to the human arm. We could confirm that the volume of Oxy-Hb, Deoxy-Hb and total blood volume were well monitored by using our instrument. Now we started to apply this technique to the human newborn. Furthermore, we started the experiments of the near-infrared tomography for the small animals on the basis of this technique.

Animals↗
PubMed1989

[Localization of a variant of herpes simplex virus type 1 in the western Japan].

We previously reported that a variant of herpes simplex virus type 1, which we found by Bg1 II digestion of many Japanese HSV-1 isolates' DNA's, was isolated frequently in two regions of Western Japan, i.e. Yamaguchi and Fukuoka. In this paper, we analyzed 280 more isolates from eleven regions in Japan. In four western regions of Japan, i.e. Osaka, Shimane, Yamaguchi, and Fukuoka, the isolation frequency of the variant was very high, and its proportion among all the isolates from those regions was 30 to 50%. On the other hand, in four eastern regions of Japan, i.e. Akita, Iwate, Miyagi, and Yamanashi, the proportion was 0 to 11%. In two central regions, i.e. Aichi and Kyoto, the proportions were 16 and 22%, respectively. Thus, the variant seems to be localized in the western regions of Japan.

DNA, Viral↗
PubMed1988

[Comparative studies on the antitumor activity of the fluorinated pyrimidines 5'-DFUR, tegafur, UFT and FUra on various murine tumors].

Antitumor activities of fluorinated pyrimidines by oral administration were compared with various murine tumor models. 5'-Deoxy-5-fluorouridine (5'-DFUR) showed a better antitumor activity in terms of the growth inhibition and increase of the survival time than those of 5-fluorouracil(FUra), tegafur and UFT, particularly with respect to the chemotherapeutic indices. The activity of these fluorinated pyrimidines were further investigated in more detail with mice bearing colon 26 adenocarcinoma to suggest some means to optimize their treatment regimens in clinical trials. 5'-DFUR showed the activity irrespective of the size of tumor mass at the time of start of therapy. Additionally only 5'-DFUR was safely administered to the mice daily for long period up to more than 100 days, suppressing the tumor growth and increasing the survival to great extent.

Animals↗
PubMed1987

[Antitumor effects of 5'-deoxy-5-fluorouridine (5'-DFUR) against various murine tumors in combination with recombinant interferon alpha or cytostatics].

Antitumor effects of oral fluorinated pyrimidines including 5'-DFUR and their combination with recombinant interferon (rIFN) alpha A/D (Bgl) or cytostatics were investigated using various tumor models in mice. 5'-DFUR was more effective against Colon 26 than tegafur and 5-FU as a single agent, and their therapeutic indices were 14.7, 2.3 and 1.2, respectively. In combination with various cytostatics, 5'-DFUR as well as 5-FU and tegafur showed better efficacy against mouse Colon 26, Meth A fibrosarcoma and A755 adenocarcinoma than any other single agents. Combination therapy with 5'-DFUR and rIFN-alpha A/D also showed better efficacy against all seven murine tumors tested than their single therapy. In these combination therapies, increased toxicities measured by a body weight change and the incidence of toxic death were also observed to some extent. Among combinations with fluorinated pyrimidines, those with 5'-DFUR showed the toxicities at a lesser degree than those with 5-FU or tegafur. These results indicate that 5'-DFUR would be useful for the multiple combination chemotherapy like 5-FU and tegafur.

Animals↗