[The effectiveness of fractionated exposure of sarcoma M-1 to gamma-radiation and fast neutrons].

The effectiveness of fractionated exposure to gamma- and neutron radiation in their separate and combined use on the growth and functional morphology of mutant p53 sarcoma M-1 in rats was studied. Investigation techniques included immunostaining of PCNA and mutant p53 expressing cells, determination of mitotic activity and apoptotic death of tumor cells, as well as computer analysis of microscopic images. The antitumor efficacy of different types of radiation is shown to be determined by different levels of apoptosis induction, reduced proliferation and cellularity. Neutron radiation of the impulse generator has a marked damaging effect on the vasculature and the development of tumor necrosis. Fractionated irradiation at equal daily doses led to the decrease in the relative effectiveness of radio-inactivation of tumor cells. After 9 fractions of irradiation, the calculated value of the RBE of fast neutrons normalized to the input dose of 1 Gy by the coefficient of tumor growth inhibition, a reduced proliferative activity of PCNA and induced apoptosis of tumor cells was 3.4, 3.7 and 3.1, respectively. In the mode of daily superfractionation with splitting the dose in two fractions, the effectiveness of the combined exposure corresponded to the additive effect of gamma- and neutron radiation with a tendency toward synergism. There are reasons to believe that high resistance of sarcoma M-1 to the ionizing radiation impact is due not only to a fraction of hypoxic cells, but also the mutant status of p53 gene.

[The study of peptide effect in the mechanisms of angiogenesis and forming of microenvironment of the tumors in old rats]. / Issledovanie roli peptidov v mekhanizmakh angiogeneza i formirovaniia mikrookruzheniia opukholei u starykh krys.

The experiments were performed in rats with transplanted sarkoma M-1. The injections of synthetic peptide vilon at the doses 0.5 mcg sigificantly increased the apoptosis of tumor cells in the experiment as compared to the control group. So vilon has possessed the oncomodulating action on the transplanted carcinoma. The injections of epigene lead to the inhibition of the sarcoma growth due to the development of the hemorragic necrosis and apoptosis increased. The results obtained suggested that vilon and epigene are the perspective preparates in the cancer therapy.

[Combined effect of vilon and cyclophosphane on tumor transplants and lymphoid tissue explants in mice and rats of various age]. / Sochetannoe vliianie vilona i tsiklofosfana na transplanty opukholei i éksplantaty limfoidnoi tkani myshei i krys raznogo vozrasta.

The experiments were performed in mice with transplanted Lewis lung carcinoma. The injections of synthetic peptide vilon at the doses 1 mg/kg significantly increased the survival of mice. So vilon has possessed the oncomodulating action on the transplanted carcinoma. The synchronous injection both of vilon and cyclophosphan at the doses 100 mg/kg decreases the survival of mice. There was also studied in spleen organotypic tissue culture the effect of vilon and cyclophosphan on the development of explants of rats of various age: 1 day and 2 years old. Vilon stimulated apoptosis both in young and old rats, but the inhibitory effect of cyclophosphan was abolished in the presence of vilon in culture media at the dose 5 ng/ml. The results obtained suggested that perspective preparates in the cancer therapy--vilon and cytostatic drugs-, must be used not synchronously.

[Functional morphology of organotypic culture of spleens from rats of various ages exposed to vilon]. / Funktsional'naia morfologiia organotipicheskoi kul'tury selezenkoi krys razlichnogo vozrasta pri deistvii vilona.

A synthetic dipeptide vilon (Lys-Glu, 20 ng/ml) was added to a cultural medium of explants taken from rats of 3 days, 3 weeks and 2 years of age. The peptide induced morphologic stability of the tissue and activated the regeneration and functional activity of cells. The stronger effect on the explants taken from the old rats suggests that vilon is a candidate for geriatric research and practice.

[Functional morphology of an organotypic liver culture exposed to the peptide livagen]. / Funktsional'naia morfologiia organotipicheskoi kul'tury pecheni pri deistvii peptida livagena.

In this study the results of the tetrapeptide livagen effect on functional morphological characteristics have been produced. Under the data of the immunocytochemical and morphometrical analysis, tetrapeptide stimulates structural and functional homeostasis of cell populations in the liver culture. It was demonstrated that the main activity of investigated peptide had been directed to the stabilisation of morphological safety and reinforcement of the processes of cellular and intracellular forms of regeneration.

[Effect of epithalone on growth kinetics and functional morphology of M-1 sarcoma]. / Vliianie épitalona na kinetiku rosta i funktsional'nuiu morfologiiu sarkomy M-1.

The growth of subcutaneously-transplanted sarcoma M-1 in rat was inhibited by injection of a synthetic tetrapeptide--epitalon (2.5 (micrograms/kg). The effect lasted for two weeks after injection course. Decrease in proliferative activity was not associated with the drug's immediate cytostatic action on tumor cells. The specific mechanism of the drug's action via blood flow was shown by morphological signs of hemorrhagic necrosis of tumor and increased apoptosis of tumor cells.

[Growth kinetics and functional morphology of M-1 sarcoma in rats before and after gamma-irradiation]. / Kinetika rosta i funktsional'naia morfologiia sarkomy M-1 u intaktnykh krys i posle gamma-oblucheniia.

The study was concerned with growth of sarcoma M-1 and basic morphological characteristics of proliferative activity of cells of this strain as well as apoptosis of cells at different stages of tumor progression in rats before and after a single gamma irradiation at 30 Gy. At the parenchymal periphery which determines tumor growth, the PCNA index of proliferating cells was 76.5%; spontaneous cell death--0.28%. During post-irradiation period, the sarcoma PCNA index fell to 62.3% while the apoptotic index rose five-fold. These findings support the concept of radiation-induced apoptosis being a major pathogenetic factor responsible for effectiveness of radiotherapy of tumors. Indirect evidence on PCNA immunostaining suggested that synthesis of this cyclin is sensitive to the level of oxygen input in the cell, yet it offers sufficient resistance to gamma-radiation.

[Effect of pineal peptides on neuroendocrine system after pinealectomy]. / Vliianie peptidov pineal'noi zhelezy na neiroéndokrinnye vzaimosviazi posle pinealéktomii.

Removal of the pineal gland leads to structural and functional rearrangement of gastric endocrine cells and thyroid C-cells in albino rats, as was shown by immunohistological methods and morphometry. Injection of pineal peptides epithalone and epithalamine eliminated these changes. Biological activity of epithalone is believed to be higher than that of epithalamine.

[Effect of cycloferon on dissemination of Lewis lung carcinoma in mice and rhabdomyosarcoma ra-23 in rats]. / Vliianie tsikloferona na metastazirovanie kartsinomy l]egkikh Lewis u myshei i rabdomiosarkomy ra-23 u kryc.

Tumor growth and proliferative activity of tumor cells were suppressed and the number of pulmonary metastases in C57B16 mice decreased 3.3-fold following seven injections of cycloferon (100 mg/kg body) to induce interferon production. Injections were carried out 1-16 days after subcutaneous transplantation of Lewis lung carcinoma. After mice were immunized with ovine red blood cells, cycloferon administration raised thymus-dependent humoral immune response. After eight injections of cycloferon (50 mg/kg body) into rats, from day of intravenous transplantation of rhabdomyosarcoma RA-23 until day 20, no significant effect on metastasizing into the lung was recorded. However, single injection of cyclophosphamide 50 mg/kg inhibited metastasis formation. The highest suppressor effect was registered with combination cycloferon-cyclophophamide treatment: mean weight of metastasis decreased by half, as compared with treatment with cyclophosphamide alone. Both drugs caused karyotypical abnormalities to occur in metastatic cells. Tumor growth and spreading suppression after cycloferon should be attributed to cytotoxic antitumor action, cell proliferation inhibition and immunomodulating effect.

[Current methods for studying the functional morphology of apud cells]. / Sovremennye metody izucheniia funktsional'noi morfologii éndokrinnykh kletok.

The paper reviews methods for studying functional morphology of endocrine cells histochemistry and immunohistochemistry, radioautography and methods of ultrastructural verification of secretory granules. Methodological approach is illustrated by the authors' results on the influence of ionizing radiation and tumor growth on the cells of the diffuse endocrine system.

[Autoradiographic and immunohistochemical analysis of 3H-melatonin distribution in endocrine and non-endocrine organs]. / Radioavtograficheskii i immunogistokhimicheskii analiz raspredeleniia 3H-melatonina v éndokrinnykh i neéndokrinnykh organov.

The comparison of the results of the autoradiographical and immunohistochemical study showed the discrepancy between the distribution of the radioactive label and the histotopographical localization of the melatonin-immunoreactive cells in the suprarenal glands, duodenum, pancreas and spleen after five minutes, one and three hours of the 3H-melatonin injection. It was shown that the exogenous 3H-melatonin is metabolizing rapidly and the products of its metabolism are spreading all over the organism. The exogenous 3H-melatonin may be accumulating in the separate endocrine and non-endocrine cells of the different organs. The results of this investigations open the perspectives for the future study on the behavior of the melatonin in the organism.

[A modification of Grimelius' method for the identification of apudocytes on semithin sections]. / Modifikatsiia metoda Grimeliusa dlia identifikatsii apudotsitov na polutonkikh srezakh.

Modified Grimelius method of the apudocyte identification on the semithin sections is described and used for the study of the duodenum endocrine cells. The method gives the possibility to study the distribution of secretory granules in the endocrine cell cytoplasm and increases the possibilities of taking samples for the ultrastructural analysis of apudocytes.

[APUD and mast cells of the gastrointestinal system: immunohistochemical and ultrastructural identification]. / Apudotsity i tuchnye kletki zheludochno-kishechnogo trakta: immunogistokhimicheskaia i ul'trastrukturnaia identifikatsiia.

A rationale for sequential immunohistochemical studies of the endocrine function of APUD cells is described, as exemplified by a study of serotonin-containing cells in rat small intestine, involving preparation of paraffin and semithin sections of epoxide resin-embedded tissue, followed by electron-microscopic examination of cells detected by the immunoperoxidase technique. With the approach described, it has been shown that a positive immunohistochemical reaction to antiserotonin antiserum is given, along with EC cells, by those mast cells disposed in groups near the EC cells as well as among connective-tissue cells of villi under the basement membrane. It is suggested that by collecting and accumulating the serotonin synthesized by specialized EC cells, mast cells transport it to sites of utilization as required by the specific arrangement.

[Effect of various concentrations of 3H-thymidine on the kinetics of Chinese hamster cell division]. / Vliianie raznykh kontsentratsii 3H-timidina na kinetiku deleniia kletok kitaiskogo khomiachka.

A study of the asynchronous culture of Chinese hamster fibroblasts by autoradiography has shown that the pulse (15 min) incorporation of 3H-thymidine in nuclear DNA influences the kinetics of labeled cell proliferation. The results obtained suggest that one of the early biological effects of the pulse incorporation of 3H-thymidine is a delay in the occurrence of the first mitosis. With the concentration of 3H-thymidine 37 kBq/ml the slowing down of of the movement of labeled cells in the cycle is detected by a shift and overlapping of waves of labeled and unlabeled mitotic cells. In an increase of the concentration up to 370-925 kBq/ml the pattern of the curves of labeled mitotic cells is distorted. These distortions are well interpreted by the nature of change of the index of labeled and unlabeled mitotic cells. A lowered index of labeled nuclei points to a decrease in the proliferative activity of labeled cells. After an increase in 3H-thymidine concentration from 37 up to 370-925 kBq/ml the mitotic activity of cells labeled at the end of S-phase decreases from 1 to 0.6-0.1% respectively. With the concentration of 925 kBq/ml for these cells incorporating 3H-thymidine at the end of S-phase, a delay of the entry into mitosis reaches 6-8 h. Autoradiography data with the assessment of granule density suggest that mitotic activity and the period of delay in the occurrence of mitosis depend on the dose of irradiation with intranuclear tritium. Thus the tritium dose rate after 15 min of incubation with 3H-thymidine is 0.03, 0.27 and 0.69 Gy/h for concentrations 37,370 and 925 kBq/ml respectively.

[Electron-radioautographic analysis of 3H-thymidine distribution in the cell nuclei of the Chinese hamster]. / Elektronno-radioavtograficheskii analiz raspredeleniia 3H-timidina v iadrakh kletok kitaiskogo khomiachka.

Three types of the label localization in the nuclei of Chinese hamster fibroblasts, growing for 9 and 13 hours with 3H-thymidine, were detected using electron microscopic autoradiography: 1. The label is relatively evenly distributed throughout the karyoplasm. 2. Silver grains are concentrated as stripes through the nucleus; a high label density is also found in the nuclear periphery and around the nucleolus. 3. The label is mainly concentrated over the condensed chromatin adjacent to the nuclear membrane. The cells labeled in the first half of S-phase and selected with colchicine in postsynthetic phase of the 1st and the 2nd cycles are characterized by the second and third types of label distribution. In the cell nuclei fixed in the postsynthetic period of the second cycle, the label localization in stripes is discontinuous. The results indicate that during cell transition from S to G2 the newly-synthetized DNA changes its localization in the nucleus. It is suggested that the second type of label distribution depends on the interphase chromosome concentration in definite zones of the nuclear volume after S-phase termination, and the third type label localization is connected with the formation of prophase chromosomes.