[Prognosis of efficacy of organ-saving treatment of invasive bladder cancer]

It is suggested that Scr-index for radiation-induced apoptosis in leukocytes in vitro be determined prior to combined therapy of urinary bladder cancer in order to estimate its efficacy. It was identified by studying leukocytes of peripheral blood from patients in whony white blood cells DNA level decreased after exposure to 2 Gy and 3-hr incubation at 37 degrees C. Values over 1.0 predicted relatively longer relapse-free survival. Scr-index of over 1.20 pointed to an insignificant decrease in leukocyte count during therapy. When it ranged 1.00-0.75, leukocyte count fell by approximately 25%; S(cr)-index below 0.55 indicated grade III blood poisoning.

[The hemathological reactions in rats after partial screening from natural electromagnetic fields]

The influence of partial screening of EMF on the composition of white blood cells was studied in the experiments on rats. Two kinds of copper rings were used in these experiments: individual for each rat and common for the cage. It was shown that inside the ring the composition of blood cells was changed--in 3-5 hours the number of granulocytes increased and in 24 hours it restored to the initial level. The effect was more expressive in the experiments using individual rings. In control groups the experiment with plastic rings didn't reveal this effect. It was presumed that EMF prevented the decay of granulocytes. It leads to the increase of their guantity. It was revealed that there was a positive correlation between Ki-indexes of geomagnetic field (GMF) in 1-2 days before the experiments and the number of granulocytes in rats during 1995-2002. Ki-indexes reflect the degree of GMF disturbance. During magnetic storms the spreading of EMF in radio-frequency range changes. It was presumed that the effect of partial screening of EMF of rats and the activity of magnetic storms are similar in their influence on the composition of white blood cells of rats.

[Vilon effect on consequences of repeated radioactive and mercuric impact in small doses]

The purpose of the study was to determine the efficacy of vilon administration in rats after reiterated exposure to ecotoxicants (mercury in concentration near to maximum allowable one and gamma-radiation in small dose). In 24 hours after repeated radioactive and mercuric impact (RMI) and for 30 consecutive days the animals reported lymphopenia. At the same time the indices of DNA leucocytes content and structure did not differ from the parameters of intact animals, this could evidence the development of adaptation reactions. Vilon administration led to the normalization of the lymphocytes number by the 30th day after repeated irradiation (contrary to the radioactive- chemical control), while the number of granulocytes in the test group was higher than that in the intact control group. Study of the survival rate in rats revealed that Vilon reduced morbidity of rats in the course of 15 months after RMI.

[Influence of cultivation conditions on bacterial DNA content and bacterial membrane permeability]

The study included measurement of intracellular and extracellular DNA content and evaluation of bacterial membrane condition during plankton growth and in isolated communities. This was performed at different stages of bacterial development and after heating at the temperature of heat shock system activation. The content of intracellular bacterial DNA in the community decreased after 72 hours of cultivation growth more prominently than during plankton growth. Change of intracellular bacterial DNA content in the community overtook the increase of membrane permeability, which may indicate the onset of apoptosis. Heating at 420' decreased the permeability of bacterial membranes in the community, but did not affect this parameter in the bacteria during plankton growth. Extracellular DNA was found in the matrix of the communities after 24 hours of growth. Appearance of this DNA after 48-74 hours of cultivation may be associated with apoptotic process.

[Effect of selenium on reactions of elderly rats affected by low doses of radiochemical exposures]

The 18-months-old female rats received with drinking water Hg2(NO3) in concentration of 1 mkg/l in account to metal and a preparation of selenium "Neoselen" (Na2SeO2) in concentration of 1.3 ml/kg/day, respectively, during 1 month before and 1 month after single gamma-irradiations with 25 cGy doses. Are established early (through 24 h after an irradiation) cytologic and genotoxic reactions in leukocytes of blood, and also hematological, biochemical reactions and changes of the content and frame DNA of leukocytes of blood in 30 day after an irradiation? Features of action of low doses of radiation in a combination to ions of mercury and their combination with a preparation of selenium are revealed. Communication of postradiating effects--changes of indexes of DNA of leukocytes of blood with reduction of life expectancy of animals is shown. The data are received, permissive to draw the conclusion, that the preparation of selenium in utilised concentrations, essentially not influencing on lifetime at low doses of radiation--mercury affecting is capable to improve quality of life of elderly animals

[The influence of geomagnetic field on blood leukocyte radiosensitivity and gender determination in humans]

The gender and age features of the geomagnetic field (GMF) influence (K-indexes) on the leukocyte radiosensitivity (S) in human blood in case of normal and enhanced levels of metal-ecotoxicants (Pb, Cd, Hg, Mn, Zn, Cu) in blood was studied, as well as the impact of the GMF intensity alterations on the child gender determination. In the whole studied population (n = 244) it was observed a negative relationship between S- and K-indexes. It was shown that the most changes of blood leukocyte radiosensitivity depended on the GMF oscillations in men older than 45 years. In case of metal-ecotoxicant concentrations in blood near normal level there were observed significant relationships between S- and K-indexes, which was infringed by more than 2-fold excess of these toxicant concentrations in blood. Retrospective analysis showed that in case of the GMF intensity enhancement in the conception moment the girls were born mostly, and in case of the lowering--the boys were.

[Prognostication of hematotoxicity for radio- and chemotherapy in patients with breast cancer]

The effectiveness of radiation and chemotherapy for breast cancer depends on individual response to drug-induced toxicity. The response can be evaluated by means of myelodepression. To this end, changes in leukocyte DNA level after ex vivo gamma radiation test were used as a criterion. Patients, aged 29-78, with tumors stage IIIB-IV received standard radiotherapy (50 Gy) or cyclophosphamide-methotrexate-5-fluorouracil (CMF). Clodronate alone was given to 26 patients and prior to a CMF course. The method proved prognostically effective since it revealed a significant inverse relationship between S-index and leukocyte nadir for both modalities. However, chemotherapy resulted in more pronounced leukopenia. With clodronate administration, the correlation was not significant. When clodronate was supplemented with CMF chemotherapy involved a significant relationship was observed between the two factors.

Modification of uterotropic effect of estrogens by whole-body gamma-irradiation

The effect of gamma-irradiation on the realization of the effects of estrogens was studied on rats treated with N-acetylcysteine, vitamins C and E, melatonin, and carnosine or subjected to forced swimming in a training mode. Irradiation (0.2 Gy) in combination with estrogens and without correction therapy induced genotoxic changes in the uterus, while irradiation in a higher dose (2 Gy) predominantly potentiated the hormonal effect of estrogens. Correction of the revealed abnormalities was achieved mainly with carnosine. The peculiarities of "estrogen toggle (re-targeting) effect" under the effect of gamma-irradiation and its elimination differed from those induced by ethanol intake or tobacco smoking, which is important for understanding the mechanisms of hormone-induced carcinogenesis.

[Specific response to benzo(a)pyrene treatment depending on mode of administration in rats]

Mathematical and statistical procedures were used to identify individual response in rats to benzo(a)pyrene (BP) treatment versus dose and regimen (single or repeated administration). Primary experimental data were suitably processed to exclude extreme values. A significant correlation was established between life-span and urine level of (+/-)-trans-7,8-dihydroxy-7,8-dihydrobenzo(a)pyrene (7,8-BP) after BP administration. It was found that, with single administration regimen, individual response to the carcinogenic agent correlated primarily with efficiency of excretion of the active forms of BP while in chronic experiment--with deactivation of the agent by enzymes.

[Comparative study of DNA-specific dyes of the indole and benzimidazole derivates]

Various models of complex formation of low-molecular ligands with DNA are considered. Using the Scatchard model, parameters of binding of fluorescent monophenylindole, monophenylbenzimidazole, and bisbenzimidazole dyes with calf thymus DNA were evaluated. By means of graphic (nonparametric) and correlation analysis, various spectral and complexation properties of these dyes in the presence of DNA are compared.

[The use of cycloferon in experimental radiotherapy of tumors]

The biological activity of cycloferon (CF) used in interferon manufacture has been investigated for its therapeutic and prophylactic properties which may be used for radiotherapy of glioma. It was demonstrated in experiments on rats that use of CF is most effective at an early stage of irradiation due to decrease in tumor mass which does not occur in case of irradiation alone. When used at a later stage, CF caused certain hematological indices of immunity to rise. CF did not produce an antitumor effect of its own. It successfully competed with Leukomax when used to bring blood indices in irradiated tumor-bearing animals back to normal.

[Assessment of genotoxicity and late effects of radiation and chemical exposures]

The 3-month-old female rats received with drinking water PbCl2 or Hg2(NO3)2 in concentrations 100 or 1 mkg/l in account to metal, respectively, during 1 month before and 1 month after single gamma-irradiation with 25 or 50 cGy doses. The features of action of lead- and mercury-ions revealed in combination with low doses radiation. In case of the mercury ions introduction the relationships had been shown between early postradiation biochemical effects (changes of blood leucocyte DNA indexes) and blood granulocyte changes in 1 month after irradiation, and correlation of postradiation repair results with life span shortening as well.

Leukopenia prognosis during radiation therapy in patients with Hodgkin's disease

The investigation goal of the present report is to use the early post-radiation peripheral blood DNA content changes during radiotherapy (RT) of cancer patients for the prognosis of the subsequent leukopenia value. Twenty-three primary patients with II-III stage Hodgkin's disease were treated at the linear accelerator of 15 Mev electrons by usual fractionation to total 40 Gy dose. The blood DNA content was fluorometrically determined by 4', 6-diamidino-2phenylindole before treatment, then 24 hrs after the 1st irradiation dose, in the middle and at the end of RT course. Retrospective analysis of obtained data demonstrated, that the first group of patients, having blood leukocyte levels above 3 x 10(9)/l at the end of RT, revealed an average blood DNA concentration decrease only after the middle of treatment course. The second group of patients, having at the end of RT severe leukopenia, showed an approximately twofold decrease of the DNA concentration after the first irradiation in 62% of cases. The biochemical change was not accompanied by a proportional decrease of the leukocytes amount. The DNA content fall, at the middle and at the end of RT course, was conditioned both by lymphocytes and granulocytes. These changes were not practically interfaced with plasma changes. Thus, a given biochemical criterium may be used as a sensitive index for the prognosis of leukopenia values after the RT beginning. Such a conclusion was confirmed by in vitro test-irradiation of blood specimens of primary patients with Hodgkin's disease. A significant correlation was found between the new index and the level of leukopenia of the patient's blood during post-treatment course.

[Spectral properties of bisbenzimidazole dyes upon interaction with DNA]

Absorption and fluorescence spectra of a series of bisbenzimidazole dyes were studied in the presence of various concentrations of DNA and in diverse media. Variations in spectral properties of the compounds under study were found to depend on the measurement conditions. The bases for selecting the optimal composition of the media for DNA detection were presented. The modes of substrate-ligand binding and the dynamics of the alterations of fluorescent properties of structurally varying dyes upon their interaction with DNA were considered.

Leukopenia prognosis by radiation therapy of patients with Hodgkin's disease

The investigation goal of the present study is the possible utilization of early postradiation peripheral blood DNA content changes during radiotherapy (RT) of cancer patients for prognostic purposes related to the subsequent ascertaiment of leukopenia values. Twenty-three primary patients with II-III stage Hodgkin's disease were treated at the linear accelerator of 15 Mev electrons by usual fractionation to a total dose of 40 Gy. The blood DNA content was fluorometrically determined by 4',6-diamidino-2-phenylindole before treatment, 24 hrs after the first irradiated dose, in the middle and at the end of RT course. Retrospective analysis of obtained data demonstrated that the first patients' group with blood leukocyte level above 3 x 10(9) cells/l at the end of RT, revealed an average blood DNA concentration decrease only after half of the treatment course. The second group of patients, complaining at the end of RT severe leukopenia, showed a two-fold decrease of the DNA concentration after the first irradiation in 62% of cases. The biochemical changes were not accompanied by a proportional decrease of the leukocytes number. The early decrease of DNA content drop, at the middle and the end of RT course, was conditioned both by lymphocytes and granulocytes. These changes were not practically interfaced with plasma changes. Thus, given biochemical criteria may be used as a sensitive index for the prognosis of leukopenia values after the RT beginning. As confirmed by test-irradiation in vitro of blood specimens of primary patients with Hodgkin's disease. There was a significant correlation between the new index and the level of leukopenia during post-treatment course.

[Mechanisms for changing fluorescent properties of bis-benzimidazole dyes]

Spectral properties of a series of externally binding substrate-specific bis-benzimidazole dyes that were either bound or not bound to DNA were studied. Feasible mechanisms of variation in fluorescent properties of the dyes under study were considered depending on their chemical structure. Contribution of the rotational diffusion and the donor-acceptor interactions to the prediction and explanation of fluorescent properties of the substrate-specific dyes was discussed.

[Changes in nucleotide DNA structure and adhesive properties of blood leukocytes in early period after irradiation of animals]

Postirradiation changes of adhesive properties and supercoiled nucleoid DNA structure of blood leukocytes were studied in Macaca nemestrina and in rats. The dynamics of membrane changes demonstrated a temporary increase of the leukocyte adherence 24 h after nonlethal irradiation of rats, followed by a decrease of this parameter to normal levels on h 48. After lethal irradiation of both animal species the increase in adhesive leukocytes fraction was shown already on hr 3. This higher index was observed until the end of experiments (5 days). Early (on h 3-6) temporary loosing of supercoiled DNA structure was demonstrated in the total blood leukocytes of nonlethally irradiated animals, this seems to be connected with lymphocyte changes. This process was not dependent on altered adhesive properties of leukocyte membranes. The membrane changes of leukocytes preceded decondensation of supercoiled DNA after lethal irradiation of animals. Loosing of supercoiled DNA progressively increased on hour 24 and in later postirradiation period.

[Structural changes in the DNA of the blood nucleotides and the development of late sequelae in irradiated rats]

Fluorescent analysis of structural changes of nucleotide in the blood associated with AT fragments has been studied in rats, gamma-irradiated with doses of 2 and 4 Gy. It was demonstrated that the haematological, gerontological and cancerogenic late consequences were preceded by the structural genomic disturbances determined by 30 day after irradiation.

[Spectral features of amines of 2-phenylbenzazoles upon interaction with DNA]

Absorption and fluorescent spectra of various synthetic aminophenyl derivatives of benzoxazole, benzothiazole and benzimidazole have been studied to estimate the efficiency of their binding with DNA. The significance of different functional groups of the fluorochromes for their interaction with DNA was determined, and main demands are formulated to the compounds to be used as potential fluorescent probes for DNA studies.

[Fluorescence characteristics of dynamic changes in the DNA structure of peripheral blood cells in irradiated rats]

A simple approach is proposed to determine locally denatured sites and stability characteristics of secondary DNA structure. The method is based on the analysis of the initial part of melting curve and the determination of changes in the optical density of DNA after heating up to a fixed temperature. The potentiality of the approach is illustrated by the experiments with DNA containing defects in the secondary structure caused by gamma-irradiation in vitro. The sensitivity of the method is less than 0.2 Gy.

[DNA damage and repair in the steps for obtaining biopreparations]

The change in the number of single-strand breaks in the genome of E. coli cells was being studied during centrifugation and drying of biomass used as raw material for producing biopreparations. The results obtained allowed the authors: (1) to establish the value of DNA damage at the two stages mentioned above and to reveal that structural integrity of the genome is mostly damaged if the humidity of dried biomass is below 15%; (2) to demonstrate that the repair of bacterial genome damages occurs after centrifugation and superficial dehydration, but it is not observed after deep dehydration.