[Experimental study of the antitumor anthracycline antibiotic aclarubicin (aclacinomycin A)]. / Eksperimental'noe izuchenie protivoopukholevogo antratsiklinovogo antibiotika aklarubitsina (aklatsinomitsina A).

Aclarubicin (ACR) has a selective inhibitory effect on the synthesis of RNA in the cells. The time of the antibiotic contact with the cells is an important factor in realization of its cytotoxic activity. As compared to adriamycin, ACR has a low specific activity in lymphoid leukemia P388, melanoma B16 and lung cancer LL. The therapeutic efficacy of ACR depended on the scheme of its use: in treatment of rapidly proliferating tumors such as P388 the highest effect is attained with the daily use of the antibiotic for 9 days, in treatment of slowly developing melanoma B16 the results were more satisfactory with intermittent use of the drug on days 1, 5 and 9 after the strain transplantation. The new antibiotic was highly effective on its use either intravenously or orally.

[Colony-forming ability of bone marrow hematopoietic cells in mice with transplanted leukemia during administration of carminomycin]. / Kolonieobrazuiushchaia sposobnost' gemopoéticheskikh kletok kostnogo mozga myshei s perevivnym leikozom pri vvedenii karminomitsina.

Effects of carminomycin on the colony-forming ability of bone marrow haemopoietic stem cells (CFUs) were compared in normal mice with steady state and actively regenerating bone marrow, and in P-388 and La leukemia-bearing mice. CFUs assays were performed 24 h after treatment of donor mice with the increasing doses of the drug. Leukemia-bearing mice received carminomycin on the 5th day after transplantation. The dose-effect curves were exponential for CFUS normal mice with both the steady state and active proliferation state of bone marrow. The maximal effect was found 24 h after injection of 0.7 mg/kg of carminomycin (ED50 for CFUS) being more pronounced in regenerating bone marrow. The dose-effect curves for leukemias were also exponential. In the case of La leukemia the killing of CFUs by carminomycin was the highest as compared with P-388 leukemia.

[Separation of mouse bone marrow cells by preparative electrophoresis]. / Razdelenie kletok kostnogo mozga myshei metodom preparativnogo élektroforeza.

Free-flow electrophoresis was used to separate mouse bone marrow cells. From five to eight fractions with an amount of cells sufficient for morphofunctional analysis could be obtained in different experiments. Granulocyte precursors were found in fractions with low electrophoretic mobility (EPM), whereas erythrocyte precursors in fractions with high EPM. CFUs were detected both in low and in high EPM fractions. In individual fractions the concentration of these cells was 4 times greater than in the initial cell suspension.

[Antileukemic activity of carminomycin complexes with a high-polymer DNA]. / Izuchenie protivoleikoznoi aktivnosti kompleksov karminomitsina s vysokopolimernoi DNK.

Complexes of carminomycin with DNA were prepared from lyophilized carminomycin and high polymer DNA of sturgeon milt. The complex formation was evident from a batochromic shift in the maxima at 450-600 nm and an increase in the absorption level at 545 nm. The carminomycin complexes with DNA had a relatively low general toxicity and higher antileukemic activity in studies on mice with tumor L-1210 as compared to the use of carminomycin alone. The maximum increase in the average life time of the animals was observed when a complex with a molar ratio of carminomycin and DNA of 1:10 (with respect to nucleotides) was used. It was found that the complex of carminomycin and DNA with a ratio of the components of 1:20 had a more pronounced effect on the animal hemopoiesis as compared to the use of carminomycin alone. It resulted in a more significant decrease in the number of the bone marrow myelokariocytes and peripheral blood erythrocytes and leukocytes.

[Action of carminomycin on leukemic cell proliferation and some problems of its use in the combined therapy of leukemias]. / Deistvie karminomitsina na proliferatsiiu leikoznykh kletok i nekotorye voprosy ego primenemiia pri kombinirovannoi terapii leikozov.

The effect of carminomycin on the mitotic cycle of the cells of the transplantable leukemia L-1210 and the therapeutic activity of other antitumor drugs, such as phopurine and cyclophosphane was studied on mice BDF1. It was found that the cells in phases S and G2 of the mitotic cycle were most sensitive to carminomycin. Transfer G1--S and phase G1 were characterized by resistance to the antibiotic effect. When carminomycin was used in combination with phopurine or cyclophosphane, clear dependence of the therapeutic efficacy on the treatment scheme was noted. Simultaneous administration of all the three drugs resulted in potentiation of the antileukemic effect. An analogous effect was observed when carminomycin was administered prior to phopurine or cyclophosphane. When the order of the drugs use was reverse, the efficacy of the combined therapy was significantly lower than the summation antileukemic effect of the drugs.

[Hematopoiesis in an organ culture of embryonal human liver]. / Krovetvorenie v organnoi kul'ture émbrional'noi pecheni cheloveka

It was shown by the method of multiple organ cultures on millipore filters that hemopoiesis preferably of erythroid type remained for more than one and a half months in the human embryo liver culture. General morphology of 7--50-day cultures was studied and described. Myeloid population of the cells (CFU conut) was exhausted practically by the 14--16th days of cultivation.