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Biomedical subjects

O S Zhukova

Publications and source records attributed to O S Zhukova.

At least 19 recordsLinked to original sources

[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↗

[Current results and perspectives of the use of human tumor cell lines for antitumor drug screening].

Cytotoxic screening of 2,000 chemical compounds against human tumor cell lines has identified certain antimetabolities, platinum complexes, actinomycin D derivatives and somatostatin analogs as possible antitumor agents. Differential sensitivity of such lines derived from five cancers (lung, colon, ovary, breast and leukemia) to certain antitumor agents has been established. This panel of cell lines is currently employed as a model for in vitro drug screening to identify biological response profile at earlier stages.

Antineoplastic Agents↗

[Preparation and certain properties of the liposomal substance 2,4-di(1-methyl-3-hydroxybutyl)deuteroporphyrin-IX].

A liposome preparation of a porphyrin photosensitizer for photodynamic therapy of tumors (PDT) was obtained. The in vitro efficiency of the photosensitizer was enhanced 2.5-fold through the liposome formulation. The composition and some properties of the new preparation were studied. An algorithm for a complex approach to the prediction of photosensitizer efficiencies by model experiments in vitro was developed. This approach is based on the use of two models: the determination of coefficient of distribution between n-octanol and a phosphate buffer, pH 7.4, and the determination of the cytotoxic effect on the culture of CaOv ovarian adenocarcinoma cells.

Adenocarcinoma↗

[Synthesis and biological properties of 3,5-cyclophosphates- and -amidophosphates of 1,2-O-alkylydene-6-deoxy-6-halogeno-alpha -D-glucofuranoses].

3,5-Cyclic phosphates and phosphoramides of 6-halogenated glucofuranoses were synthesized via interaction of 3,5,6-bicyclophosphites of 1,2-O-alkylidene-alpha-D-glucofuranoses with halogens (followed by treatment with nucleophilic reagents) and N-chloroamines. 3,5-Cyclic trans-dibutylphosphoramides of 6-chloro-6-deoxy-1,2-O-isopropylidene- and 6-chloro-6-deoxy-(R)-(2,2,2)-trichloroethylidene)-alpha-D-glucofuranoses were shown to possess antiproliferative activity against CaOv human ovarian carcinoma cells in vitro (CE50 of approximately 10(-5) M). Cyclic trans-dibutylphosphoramide of 6-chloro-6-deoxy-1,2,-O-isopropylidene-alpha-D-glucofuranose also displayed marked antitumor effect on P-388 transplantable murine leukemia in vivo (the maximum increase in life span of 100% was reached at the quintuple injection of 100 mg/kg daily).

Animals↗

Antitumor activity of conjugates of the oncofetal protein alpha-fetoprotein and phthalocyanines in vitro.

The several conjugates of aluminium and cobalt complexes of phthalocyanines with human alpha-fetoprotein have been synthesized. Their cytotoxic activity against tumor cells and human peripheral blood lymphocytes was studied. The experimental data demonstrate that the cytotoxic activity of alpha-fetoprotein-phthalocyanine conjugates against three types of tumor cells of various origin is much higher (for aluminium and cobalt complexes more than 1000 and 50 times, respectively) in comparison with phthalocyanines themselves. The application of phthalocyanines as conjugates with alpha-fetoprotein makes it possible to markedly enhance the selective toxicity of phthalocyanines against human tumor cells.

Aluminum↗

Antitumor activity of conjugates of the oncofetal protein alpha-fetoprotein and phthalocyanines in vitro.

The several conjugates of aluminium and cobalt complexes of phthalocyanines with human alpha-fetoprotein have been synthesized. Their cytotoxic activity against tumor cells and human peripheral blood lymphocytes was studied. The experimental data demonstrate that the cytotoxic activity of alpha-fetoprotein-phthalocyanine conjugates against three types of tumor cells of various origin is much higher (for aluminium and cobalt complexes more than 1000 and 50 times, respectively) in comparison with phthalocyanines themselves. The application of phthalocyanines as conjugates with alpha-fetoprotein makes it possible to markedly enhance the selective toxicity of phthalocyanines against human tumor cells.

Aluminum↗

[Synthesis and cytotoxic properties of anomeric 5-substituted 3'-azido-2',3'-dideoxyuridines].

Glycosylation of trimethylsilyl derivatives of 5-benzyloxymethyl- and 5-hydroxymethyluracil with 3-azido-2,3-dideoxy-5-O-benzoyl-D-ribofuranosyl chloride (prepared from ethyl 3-azido-2,3-dideoxy-5-O-benzoyl-D-ribofuranoside) and subsequent deacylation gave in both cases a mixture of anomeric 3'-azido-2',3'-dideoxy-5-benzyloxymethyl-or 5-hydroxymethyluridines. The anomers were separated by preparative TLC and their structures were studied by UV, IR and 1H-NMR spectroscopy. It is shown that 1-(3-azido-2,3-dideoxy-alpha-D-ribofuranosyl)-5-benzyloxymethyluracil has cytotoxic activity in vitro: in 10(-5)-10(-4) M concentrations it inhibits the thymidine incorporation into DNA of CaOv cells on 78.6-95.2%.

Antiviral Agents↗

[Synthesis, conversion and biological activity of 5-substituted 2'-deoxyuridines modified by carbohydrates].

5-Benzyloxymethyl(Bom)-2'-deoxyuridine and its alpha-anomer were used as the key compounds for syntheses of thymidine analogues or 3'-derivatives. Anomeric 5-Bom-2'-deoxyuridines were synthesized from 5-Bom-uracil and 2-deoxy-3,5-di-O-p-toluyl-alpha-D-ribo-furanosyl chloride by means of the silyl method. 5-Bom-2'-deoxyuridine was transformed successively to 3',5'-di-O-mesyl derivative, 2,3'-anhydro-1-(2-deoxy-5-O-p-toluyl-beta-D-xylofuranosyl)-5-Bom-uracil and 3'-azido-2',3'-dideoxy-5-Bom-uridine. Treatment of the last with SnCl4 in methylene dichloride--methanol led to 3'-azido-2',3'-dideoxy-5-methoxymethyluridine. Under the same conditions the 5-methoxymethyl derivative was obtained from 3',5'-di-O-p-toluyl-5-Bom-2'-deoxyuridine. Interaction of 1-(2-deoxy-alpha-D-ribofuranosyl)-4-Bom-uracil with SnCl4 in methylene dichloride as well as the hydrogen transfer hydrogenolysis in the presence of cyclohexene and Pd(OH)2/C in ethanol led to 1-(2-deoxy-alpha-D-ribofuranosyl)-5-hydroxymethyluracil. Only 3'-azido-2',3'-dideoxy-5-Bom-uridine showed a cytotoxic activity against CaOv cells in vitro: in 10(-5)-10(-4) M concentrations it inhibits the thymidine incorporation into DNA by 78.8-95.1%. Elucidation of antitumor activity in vivo showed that this nucleoside inhibits growth of solid tumours, Ca755 and LLC, by 79 and 79-83%, respectively, but has no therapeutic effect against lympholeukemia P388.

Carbohydrates↗

Effect of gangliosides on binding, internalization and cytotoxic activity of ricin.

The only gangliosides in Burkitt's lymphoma EB-3 cells is GM3. Treatment of Burkitt's lymphoma EB-3 cells with gangliosides GM1 or GM3 results in their binding to and partial incorporation into the cell membrane. About 25% of cell-associated ganglioside GM1 can interact with the ricin. However, such an increase in the number of binding sites does not enhance but rather decreases the cytotoxic effect of ricin. A similar protective effect was observed when the cells were pretreated with ganglioside GM3. In contrast, the increase in ricin biding sites caused by pretreatment of the cells with neuraminidase was accompanied by increase in ricin cytotoxicity. These differences may be related to observed differences in the rate of ricin-endocytosis by native and ganglioside-treated cells.

Binding Sites↗

[Derivatives of antineoplastic antibiotics of the daunorubicin series containing methylurea or nitrosomethylurea residues].

Derivatives of antitumour anthracycline antibiotics containing N-methylurea moiety in the carbohydrate ring were obtained by the interaction of methyl isocyanate with daunorubicin, doxorubicin, carminomycin and daunorubicin derivatives, substituted at C-13 or C-14 positions. N-Nitrosation of these compounds yielded modified anthracycline antibiotics containing the N-methyl-N-nitrosourea substituent at C-3' position. Alkaline degradation of these derivatives produced, through corresponding isocyanates cyclic 3'-N,4'-carbonylderivatives. In these anthracycline derivatives with sugar cycles conjugated with oxazoline-2-ones the predominant conformations of sugar ring has changed from 1C4 to 4C1, 2,5B, or B0,3 (shown by 1H NMR spectroscopy). It was demonstrated, both in vitro and in vivo, that introduction of methylurea or cytotoxic methylnitrosourea moieties does not potentiate antimicrobial, cytotoxic or antitumour properties of these compounds.

Animals↗

A new approach to studies of cell-antibody interactions using fluorescent lipid probes.

The interaction of poly- and monoclonal antibodies against the L-chain of human Ig with Burkitt lymphoma EB-3 cells was studied using a fluorescent lipid probe, anthrylvinyl-labelled sphingomyelin, incorporated into the cell plasma membrane. Binding of the antibodies to Ig receptors on the surface was shown to induce changes in the fluorescence polarization of the probe. The high sensitivity of the method allows one to detect less than 100 antibody molecules per cell. The possibility of using cells or liposomes carrying antigens and fluorescent lipids for the determination of antibodies in solution is discussed.

Antibodies, Anti-Idiotypic↗

[Synthesis of anomeric 5-trimethylgermyl-2'-deoxyuridines and study of their antiviral and cytotoxic properties].

Glycosylation of silylated 5-trimethylgermyluracil with 2-deoxy-3,5-di-O-p-toluyl-alpha-D-ribofuranosylchloride in dichloroethane in the presence of SnCl4 and subsequent deacylation led to anomeric 5-trimethylgermyl-2'-deoxyuridines. The alpha-nucleoside inhibits HSV-1 replication in vitro, blocks 2'-deoxyuridine incorporation into DNA of hepatoma 22A cells and incorporation of thymidine into DNA of cancer ovarian cells as well. Treatment with 125 mg/kg X 5 days of alpha-nucleoside fails to increase the life-span of mice with leukemia P388.

Animals↗

[The effect of preparations of microbial glutamin(asparagin)ase on cultured tumor cells].

Glutamin (asparagin)ase from Pseudomonas boreopolis 526 is shown to produce a cytotoxic effect on the human ovary carcinoma cells (CaOv line), Fisher lympholeukemia (L-8 line) and Burkitt's lymphoma cells (P3HR line). A significant inhibition of the DNA synthesis is found in L-8 and P3HR cell lines. The enzyme is less active in the cells of the CaOv line.

Amidohydrolases↗