著者
星 昭夫 飯郷 正明 実吉 峯郎 榑谷 和男
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.21, no.7, pp.1535-1538, 1973-07-25 (Released:2008-03-31)
被引用文献数
4 4

Deamination of cytidine derivatives especially of cyclocytidine by mouse kidney cytidine deaminase was examined. Cyclocytidine was not deaminated at either pH6.5 or pH7.3 by the enzyme. Furthermore, cyclocytidine did not inhibit the deamination of aracytidine and ([I]/[S])0.5 value for cyclocytidine was over 100. As a result, cyclocytidine is found to be markedly active compound with resistance against cytidine deaminase.
著者
星 昭夫 官沢 文彦 飯郷 正明 榑谷 和男
出版者
The Japanese Cancer Association
雑誌
GANN Japanese Journal of Cancer Research (ISSN:0016450X)
巻号頁・発行日
vol.66, no.5, pp.539-546, 1975-10-31 (Released:2008-10-23)
参考文献数
12
被引用文献数
2

Combination effect of antitumor agents, including cyclocytidine and cytosine arabinoside, was evaluated on the conception of pharmacological synergism and not of therapeutic synergism. Ascites sarcoma-180 and L-1210 leukemia were used as tumor systems. In sarcoma-180 system, combinations of cyclophosphamide plus cyclocytidine or cytosine arabinoside by simultaneous administration and cyclocytidine plus Daunorubicin or Vinblastine by alternate administration provided synergism. In L-1210 system, many compounds in combination with cyclocytidine or cytosine arabinoside in both simultaneous and alternate administrations provided synergism. Combination effect of agents was affected by the schedule of drug administration. It was found that the combination effect of drugs in one tumor system cannot be generalized to that in other tumor systems, even though equally effective doses of agents were administered in both tumor systems. Toxicity of cytosine arabinoside in combination with other drugs was affected by the schedule of administration. Compounds which provided synergism in simultaneous administration provided antagonism in alternate one. As a result, it was found that alternate administration of drugs is advantageous for the activity and diminution of toxicity to the host animal.
著者
星 昭夫 池川 哲郎 池田 善明 白川 貞雄 飯郷 正明 榑谷 和男 福岡 文子
出版者
The Japanese Cancer Association
雑誌
GANN Japanese Journal of Cancer Research (ISSN:0016450X)
巻号頁・発行日
vol.67, no.2, pp.321-326, 1976-04-30 (Released:2008-10-23)
参考文献数
13

The antitumor activity of berberine, berberrubine, and their derivatives against sarcoma-180 ascites was determined by the total packed cell volume method. Berberine and tetrahydroberberine derivatives had no antitumor activity, but berberrubine (9-demethylberberine) and the ester derivatives of berberrubine had a strong antitumor activity. ED90 of berberrubine, its acetate and benzoate, were 15, 23, and 44mg/kg, respectively. The therapeutic indices (LD10/ED90 by the present method) of these compounds were as follows: Berberrubine hydrochloride, 6.7∼9.4; 9-acetyl-9-demethylberberine (9-acetylberberrubine) chloride, 7.6∼8.7; 9-benzoyl-9-demethylberberine (9-benzoylberberrubine) chloride, 3.4∼4.9.