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Biomedical subjects

L A Sedakova

Publications and source records attributed to L A Sedakova.

11 recordsLinked to original sources

Effects of T-activin and vitamin E on toxicity and antitumor activity of cyclophosphamide.

We studied the effect of combination treatment with T-activin and vitamin E on acute toxicity and antitumor activity of cyclophosphamide in mice. Combined administration of these preparations 1.37-fold increased the maximum permissible dose of cyclophosphamide without affecting its LD(50)and delayed mouse death from cyclophosphamide toxicity. Most mice died only 3 days after combination treatment with the test preparations and cyclophosphamide in doses of LD(16)-LD(84). The second peak of death from hematologic toxicity of cyclophosphamide was absent under these conditions. T-activin and vitamin E did not abolish the antitumor effect of cyclophosphamide on mice with subcutaneously implanted P-388 lympholeukemia. Tumor growth was suppressed by 100%.

Animals↗

[Cell differentiation in human melanoma cells caused by dicarbamine (ultrastructural investigation)].

The effects of dicarbamine (r) and polytransretinoic acid (PTRA) on human melanoma MEL-6 transplanted into Balb/c nude female mice have been compared by histological and electron microscopic procedures. It was discovered that long-term administration of 1.5 mg/kg dicarbamine caused melanoma MEL-6 cells to undergo terminal differentiation. As a result, the number of melanosome-containing cells was 3-4 times and the number of melanosomes in them--5 times those in intact controls. Dicarbamine effect was double that of PTRA.

Animals↗

[A novel immunoregulating hexapeptide with antineoplastic effect].

A synthesized analog of myelopeptide HP-2-->M[symbol: see text]-2 (Leu-Val-Val-Tyr-Pro-Trp) caused a significant (60-80%) and prolonged inhibition of s.c. grafted tumors P388, Ca-755, B-16 and sarcoma 180 in isogenic mice but did not affect the growth of tumor B-16 in nude mice. Nor did it influence proliferative activity or viability of cultured human tumor cells. The best results were obtained with s.c. injections of 0.5-2 mg/kg HP-2-->M[symbol: see text]-2, twice or trice a day, at 96 hr intervals. No symptoms of severe poisoning were registered at doses of HP-2-->M[symbol: see text]-2 100 times the therapeutic one. A pharmacokinetic study in mice revealed prolonged circulation of HP-2-->M[symbol: see text]-2 in blood and a high affinity for the bone marrow (t 1/2 (130.1 hr and 431.6 hr, respectively). HP-2-->M[symbol: see text]-2 restored in vitro the ascites P388-suppressed cytotoxicity of murine T-lymphocytes. HP-2-->M[symbol: see text]-2 is regarded as a candidate for clinical studies of its potential of immunocorrection in cancer patients suffering T-lymphocyte immunity disturbances.

Adjuvants, Immunologic↗

[Structure and antitumor activity of polysaccharides from the micelles of Aspergillus oryzae].

Three polysaccharide fractions active against mammary gland adenocarcinoma Ca-755 in mice but inactive against sarcoma C-180 were isolated from Aspergillus oryzae strain 5214. The main fraction, extracted from the mycelium by cold dilute alkali in the presence of sodium borohydride, was shown to be linear (1----3)-a-D-glucopyranan (pseudonigeran) according to 13C NMR spectroscopy, partial acid hydrolysis and periodate oxidation data.

Adenocarcinoma↗

[Antitumor and toxic effects of amotin].

An indole alkaloid isolated from Catharanthus roseus in the Soviet Union and named amotin differs in terpenoid moiety structure of the indole part of the molecule from the foreign preparation vinblastine and its Soviet analog rosevine. In experimental study amotin has exhibited a high antileukemic activity which was more expressed than that of vinblastine. Tolerant doses of amotin cause moderate reversible morphological alterations in hematopoietic organs, gastrointestinal mucosa, liver, kidney, adrenals, testes, ovaries.

Animals↗

[Biological properties of L-lysine alpha-oxidase in native and conjugated form].

The significant difference between biological properties of L-lysine-alpha-oxidase from Trichoderma harzianum Rifai (LO) and L-asparaginase from E. coli has been observed in vitro and in vivo. High antitumor activity was shown against 8 types of murine and rat transplanted tumors with a wide range of LO therapeutic doses: 35-350 U/mg. The LO conjugates with monoclonal antibodies CD5 specific to the surface of cell line Yurkat were obtained without significant loss of either enzymatic and cytotoxic activity or immunological specificity. The further perspective investigation for the clinical application of the native or conjugated enzymes is discussed.

Amino Acid Oxidoreductases↗