[Micronuclear and antitumor activities of two newly synthesized pyrimidine derivatives].

Micronuclear and antitumor activities of two newly synthesized iodides of pyrazolo[1,5a]pyrimidines were investigated using mice model. It has been shown that both compounds are slightly toxic and have no antitumor activity in mice with Ehrlich's ascites carcinoma. Only one of them has weak micronuclear activity. Both compounds increase substantially micronuclear as well as antitumor activities of cyclophosphamide.

[DNA comet assay for evaluation of genotoxic effects in risk groups]. / Primenenue metoda DNK-komet dlia otsenki genotoksicheskikh éffektov v gruppakh riska.

DNA comet assay (CA), gel electrophoresis of single cells, is effective in evaluating the genetic (genotoxic) effects of endogenous and exogenous agents. CA was used to study the extent of spontaneous or UV-induced DNA damages in the leukocytes in two groups at genetic risk: in Chernobyl accident liquidators and patients with familial Mediterranean fever (FMF). There was a significant increase in the number of UV-induced and excision repair-mediated DNA breaks in both risk groups as compared to control samples. The spontaneous extent of DNA breaks in the cells of the liquidators and FMF patients were similar to those in the controls. The extent of oxidative DNA damages detected during incubation with the endonuclease enzymes formamidopyrimidine glycosylase and endonuclease III were also determined in FMF patients. There were no statistically significant differences in the extent of oxidative DNA damage in the cells of FMF patients as compared to the controls. The findings give grounds to recommend CA for biomonitoring of genotoxic effects.

[The micronucleus test in human exfoliative cells as a method for studying the action of mutagens/carcinogens]. / Mikroiadernyi test v éksofoliativnykh kletkakh kak metod izucheniia deistviia mutagenov/kantserogenov.

The data concerning the application of micronucleus assay in human exfoliated cells have been analyzed in the review. These data have shown that the study of micronuclei in human exfoliated cells is very promising, sensitive and rapid method for detection of action of mutagens/carcinogens as well as antimutagens/anticarcinogens on human organism in vivo.

[Effect of the preparation "Loshtak" on the clastogenic activity cyclophosphamide]. / Deistvie preparata "loshtak" na kalstogennuiu aktivnost' tsiklofosfana.

The anticlastogenic effect of the herbal preparation Loshtak on rats and mice was tested using the same scheme of treatment and doses of the preparation as are employed in medical practice. It was shown that intragastric administration of Loshtak results in a statistically significant decrease in the clastogenic effect of cyclophosphamide injected 48 h after the end of treatment with Loshtak. High doses of Loshtak did not induce any increase in the number of micronuclei in mouse bone marrow cells. Possible mechanisms responsible for the anticlastogenic effect of Loshtak are discussed.

[The modification of the clastogenic action of 131I in the bone marrow cells of rats immunized with a tularemia vaccine]. / Modifikatsiia klastogennogo deistviia 131I v kletkakh kostnogo mozga krys, immunizirovannykh tuliaremiinoi vaktsinoi.

The influence of immunization of Wistar rats with the tularemia vaccine (TV) on the clastogenic effect of 131I was studied. The preliminary immunization of rats with TV significantly reduces the number of aberrant metaphases in bone marrow cells by 36.4% one day and by 61.6% eight days after the administering of the radionuclide in comparison with non-immunized animals. Possible mechanisms of anticlasterogenesis in animals immunized with TV are discussed.

[Effect of immunization of mice with human umbilical cord extract on micronucleus induction by cyclophosphane]. / Vliianie immunizatsii myshei ékstraktom pupoviny cheloveka na induktsiiu mikroiader tsiklofosfanom.

The influence of human umbilical cord extract (HUGE) on mutagenesis induces by cyclophosphamide in mice bone marrow cells was studied. It was shown that HUGE had no clastogenic property and decreased significantly the number of micronuclei in bone marrow cells of mice during 5 days after the last HUGE infection. We suppose that the antimutagenic effect is connected with interferon induction by HUGE.

[An analysis of the micronuclei in the oral mucosa of cancer patients for assessing the clastogenic effect of chemical preparations]. / Analiz mikroiader v slizistoi rotovoi polosti onkologicheskikh bol'nykh dlia otsenki klastogennogo éffekta khimiopreparatov.

The frequency of micronuclei in the buccal mucosa cells have been investigated in healthy persons (donors) and patients with tumors before and after chemotherapy. It has been shown that frequency of micronuclei in the cells of patients before therapy and donors were at the same level. One day after chemotherapy the frequency of micronuclei was elevated 3.2 times.

[Relation of the antitumor activity of 4'-epidoxorubicin and cytogenetic disorders of tumor cells in experimental studies]. / Sviaz' protivoopukholevoi aktivnosti 4-épidoksorubitsina s narusheniiami geneticheskogo apparata opukholevykh kletok v éksperimente.

Antitumor and cytogenetic activities of 4-epi-doxorubicin (EDR), an anthracycline antibiotic, were studied on female Wistar rats with transplantable ascitic ovary tumor (OT). It was shown that after a single administration in a dose of 3 mg/kg, EDR prolonged the average lifespan of the tumor-bearing rats by 213.4 per cent as compared to that in the controls. The maximum number of the aberrant cells in the bone marrow was observed 24 hours after injection of EDR. In 6 day it decreased to the control level. The maximum increase in the number of the OT aberrant cells was recorded 2 days after EDR injection and even in 10 days the number of the aberrant cells amounted to 20.2 +/- 1.3 per cent. It is suggestive of a high selective action of EDR and relation between the EDR antitumor activity and the disturbances in the chromosomal apparatus of the OT cells.

[Antimutagenic properties of sea buckthorn oil]. / Antimutagennoe svoistvo oblepikhovogo masla.

The influence of sea-buckthorn oil on cyclophosphamide, farmorubicin and dioxadet mutagenicity was studied. The oil decreased significantly the cytogenetic action of cyclophosphamide and farmorubicin, but not of dioxadet action. Possible mechanisms of antimutagenic action of the oil are discussed.

[The mutagenicity of animal carcinogenic agents of natural origin]. / Mutagennost' kantserogennykh dlia zhivotnykh agentov prirodnogo proiskhozhdeniia.

The current data from literature on the mutagenicity of carcinogens of natural origin are reviewed. A high correlation between carcinogenicity and mutagenicity of this group of agents is established.

[Mutagenicity of natural-origin agents carcinogenic to humans]. / Mutagennost' kantserogennykh dlia cheloveka agentov prirodnogo proiskhozhdeniia.

The current literature data on mutagenicity of human carcinogens of natural origin are reviewed. The high correlation is established between carcinogenicity and mutagenicity of this group of agents, all 10 agents are active in the Ames assay or in the cytogenetic tests, 7 of them are mutagenic in the Ames test and 8 in cytogenetic assays.

[The antitumor effect of an extract of human umbilical cord]. / Protivoopukholevoe deistvie ékstrakta pupoviny chelovecheskogo ploda.

The study was concerned with the evaluation of effect of the extract of a human fetal organ, the umbilical cord, on development and growth of such transplantable tumors as Ehrlich's ascites tumor, sarcoma 37, sarcoma 180 and Zajdela's hepatoma as well as of dimethylbenzanthracene- and benzo(a)pyrene-induced cancer. In a subgroup of animals who had been vaccinated once or twice prior to inoculation of cells, a significant inhibition of growth of tumors of all the histologies except sarcoma 180 was observed alongside with a decrease in tumor incidence and partial resorption of ascitic fluid. Preliminary vaccination of rats interfered with dimethylbenzanthracene- and benzo(a)pyrene-induced carcinogenesis reducing tumor incidence and assuring longer latent period and slower progression of cancer.

[The cytogenetic action of x-ray irradiation on the myelokaryocytes of rats immunized with a tularemia vaccine]. / Izuchenie tsitogeneticheskogo deistviia rentgenovskogo oblucheniia na mielokariotsity krys, immunizirovannykh tuliaremiinoi vaktsinoi.

Immunization with tularemic live dry vaccine administered singularly to Wistar rats skin has been studied for its effect on mutagenicity induced after whole-body X irradiation. The analysis has shown that cytogenetic disturbance induced after X irradiation with doses of 0.5 Gy and 1.0 Gy in immunized animals significantly decreases as compared to nonimmunized animals.

[Decrease in the cytogenetic effect of adriblastin and pharmorubicin with the experimental use of tularemia vaccine]. / Snizhenie tsitogeneticheskogo deistviia adriblastina i farmorubitsinas pomoshch'iu tuliaremiinoi vaktsiny v éksperimente.

Immunization of Wistar rats with tularemic vaccine has been studied for its influence on the cytogenetic effect of adryblastine and pharmorubicyn. It is shown that the number of aberrant metaphases considerably decreases in the myelocaryocytes of vaccinated rats. Antimutagenic effect is induced by the influence of tularemic vaccine on the metabolic activation processes of antibiotics and, possibly, by an increase of the activity of antioxidative enzymes in the rat organism.

[The effect of tularemia vaccine on the radioresistance of white rats exposed to x-irradiation]. / Vliianie tuliaremiinoi vaktsiny na radioustoichivost' belykh krys pri rentgenovskom obluchenii.

A single epicutaneous vaccination of Wistar rats with tularemic live vaccine 15 days before X-irradiation with doses of 6.0, 8.0 and 2.0 + 6.0 Gy was shown to increase their radioresistance. With higher doses (up to 8.0 Gy) the effect of the vaccine was less pronounced.

[Possible mutagenic action of a tularemia vaccine]. / O vozmozhnom mutagennom deistvii tuliaremiinoi vaktsiny.

No increase in the number of chromosome aberrations in the bone marrow cells of the Wistar rats was observed on the 1st, 2nd, 7th and 15th days after epidermal and intradermal immunization by tularemic live vaccine. Subcutaneous injection of great quantities of tularemic microbic cells which were not used in practice increased the number of cells with chromosome aberrations only on the second day.

[Effect of the immunization of rats with tularemia vaccine on the number of cytogenetic disorders in somatic cells induced by cytostatics]. / Vliianie immunizatsii krys tuliaremiinoi vaktsinoi na kolichestvo tsitogeneticheskikh narushenii v somaticheskikh kletkakh, indutsiruemykh nekotorymi tsitostatikami.

Cytogenetic disturbances due to cytostatic preparations--cyclophosphamide and methylnitrosourea--applied as single or ten-times administrations in different doses have been studied for rats immunized with tularemia live dried vaccine. It is established that with the application of these preparations to immunized animals the quantity of chromosomal aberrations in myelokaryocytes decreased from 1.4 to 2.2 times, compared with that in non-immunized animals.