[A trial of the efficacy of using the synthetic antioxidant dibunol in the chemotherapy of experimental tumors]. / Opyt éffektivnosti primeneniia sinteticheskogo antioksidanta dibunola pri khimioterapii éksperimental'nykh opukholei.

We studied the therapeutic efficiency of the synthetic antioxidant Dibunol alone and in combination with cytostatic drugs on animals with experimental tumors after simultaneous and successive administration. Introduction of Dibunol to animals (tumor carriers) soon after the transplantation of tumor cells had adverse consequences, stimulated tumor growth and reduced the life span of animals. Dibunol exerted a therapeutic effect only in cases of developed tumors. Simultaneous introduction of cytostatic drugs (cyclophosphamide, dimethylnitrosourea, ADEKO) and Dibunol to tumor carriers was efficient and increased the mean life span of animals. The antitumor effect of the cyclophosphamide-Dibunol combination did not, in practice, depend on the interval between introductions of these drugs. However, the mean life span and survival of animals were somewhat higher the intervals between introductions or simultaneous application of the drugs were short.

[Comparative evaluation of the antitumor, cytogenetic and immunodepressive effects of dimetinur when used perorally and parenterally]. / Sravnitel'naia otsenka protivoopukholevogo, tsitogeneticheskogo i immunodepressivnogo éffektov dimetinura pri peroral'nom i parenteral'nom primenenii.

The dimethylnitrosourea action after oral and parenteral administration was comparatively evaluated on the basis of criteria for the antitumour and cytogenetic activity, as well as for the immune (T-cell) reactivity of tumour-bearing and intact animals. A considerable antitumour effect and the induction of the overload chromosomal aberrations in tumour cells with the complete preservation of bone marrow cells were observed during the oral drug application. Dimethyl nitrosourea-induced T-cell depression in murine spleen was transitory and reversible. Thus the oral administration of the drug was shown to be optimal for realization of its therapeutical activity with the least toxic side effect on the host normal hemopoietic and immunocompetent cells.

[Dynamics of the chromosomal damages to Ehrlich ascitic cancer and bone marrow cells of mice by the antitumor preparation dimetinur]. / Dinamika povrezhdenii khromosom kletok astsitnogo raka Erlikha i kostnogo mozga myshei protivoopukholevym preparatom dimetinur.

The dimetinur effect upon chromosomes of the Ehrlich ascite carcinoma and bone marrow cell populations was analyzed by the cytogenetic method for 10 days after i.p. and i. v. drug administration in doses from 50 to 150 mg/kg. Kinetic regularities of changes in a fraction of cells with chromosome breakages and in the number of broken chromosomes per cell as well as "dose-effect" relations are determined. A linear correlation is established between the level of residual chromosome damages in a population of tumour cells and the coefficient of activity chi* characterizing the antitumour effect of dimetinur. Selectivity of the dimetinur mutagenic action expressed as a more deep and prolonged damage of the genetic system of tumour cells as compared to bone marrow cells of tumour-bearing animals is shown under conditions of a pronounced therapeutic activity.