[Influence of age of patients with bronchopulmonary pathology on low-molecular DNA concentration in blood plasma.]

The aim of the work was to determine the concentration of low-molecular-weight plasma DNA (lmDNA) in patients with COPD and chronic non-obstructive bronchitis (CnonB) of two age groups - 34-59 and 60-80 years. The levels of lmDNA in healthy donors, patients with CnonB, healthy relatives of patients with COPD did not differ, while the concentration of lmDNA in patients with COPD was significantly lower. In COPD patients aged 34-59 years, the level of lmDNA was reduced by more than 7 times, and in COPD patients who survived to 60-80 years, it was 3 times lower compared to the value of this biochemical indicator in healthy donors of the same age. The reduction of lmDNA reflected a reduced systemic apoptotic activity in the body of patients with COPD. A significant difference in the concentration of lmDNA in patients with COPD and CnonB in remission can be used for differential diagnosis of the development of these pathological processes. An increase in the low level of lmDNA in COPD patients during aging may indicate the involvement of epigenetic mechanisms in life extension.

Biphasic aggregation of a perylene bisimide dye identified by exciton-vibrational spectra

The quantum efficiency of light emission supramolecular aggregates strongly depends on the intermolecular coupling. We present a molecule which demonstrates two different aggregated structures with high and low quantum efficiency. The spectral signatures can be understood by simulating the aggregated structures and the corresponding exciton-vibrational spectra.

[Blood DNA radiosentivity as a predictive bindex of radiochemical treatment efficacy in cervical cancer patients]

Study of cervical cancer patients with I-III stage was performed with biomarker determination of the blood DNA radiosensitivity ex vivo. The biochemical index was measured before treatment start during 4 hours by use fluorescent dye. The relationship between changes of these index levels and volume tumor reductions after radiochemical treatment evidenced that blood DNA radiosensitivity was enabled to predict an outcome of the cervical cancer patient treatment earlier than the assessment of therapy efficacy by help of ultrasound measurements.

[Blood DNA Radiosensitivity May Be Predictive Marker for Efficacy of Radiation Therapy in Glioma Tumorbearing Individuals]

Animal and clinical studies were conducted to evaluate the association between the blood DNA radiosensitivity, assessed by determining the original S-index ex vivo, and the response of gliomas to irradiation in vivo. Possible modifications of the latter after administration of iron-containing water (ICW) in rats were also explored. The study was performed on the rats with subcutaneously implanted experimental glioma-35. The tumors were locally X-irradiated with a single 15 Gy dose as a radiation therapy (RT). ICW (60-63 mg · Fe 2+/l) was administered as a drinking water for 3 days before treatment. The animals underwent blood sampling for analysis of the DNA concentration and leukocyte count. The DNA index was estimated 24 h after RT. The S-index was evaluated within 4 h before RT. The mean initial S-index in the blood samples of glioma-bearing rats was 0.73 ± 0.05. Addition of ICW ex vivo resulted in a significantly increased S-index in a half of the samples. In general, the irradiated rats, which had been given pretreatment with ICW and demonstrated an ex vivo increase of the S-index to > 1.0, showed the most marked inhibition of tumor progression and the smallest tumor volume 25 days after irradiation. They also exhibited the lowest rate of growth and the longest survival. Determination of the biochemical S-index and evaluation of its changes ex vivo caused by ICW may be predictive of the response of experimental glioma to irradiation with radiomodification. The S-index may serve as a predictive indicator in clinic of the efficient evaluation of RT in patients with glioma.

Peculiarities of measuring ion energy distribution in plasma with a retarding field analyzer

Presented are the results from tailoring the retarding field energy analyzer to measure the degree of charge compensation and regular patterns in the separations of ions of different mass, with the multicomponent ion flow spreading out in the plasma-optical mass separator model.

[Predicting of the effectiveness of radiotherapy and chemoradiotherapy for cancer patients]

Studies carried out on samples of tumor and non-tumor tissue indicate that markers of radiosensitivity for predicting individual patient response to the planned radiation therapy may be the indicators of apoptosis and molecular profiles read from the DNA of patients. At present there is developed a technology for rapid and economical determining of indicators for the reasonable use of radiation therapy in the radiological practice in patients with breast cancer, bladder cancer and malignant glioblastomas by means of an evaluation of radiosensitivity of the DNA of blood.

[DNA POLYMORPHISM AND RISK OF OCCLUSIVE VASCULAR LESIONS IN PATIENTS WITH CARDIOVASCULAR DISEASES]

A method for diagnostics of occlusive vascular lesions in patients with cardiovascular diseases is proposed. Results of this study extend possibilities for diagnostics of occlusive vascular lesions in patients with cardiovascular diseases.

[Personalized treatment of tumor-bearings after prediction of radio and chemoradio-therapy efficacy by means of blood DNA radiosensitivity]

Ongoing studies on the tumor and non-tumor samples carried out worldwide give evidence that some apoptotic indexes, DNA-based microarray molecular profiling analysis as well as determination of single nucleotide polymorphisms in the genome of a patient's tumor can serve perspective markers of radiosensitivity for the response prediction in individual patients to intendedradiation therapy. Over the last years there has been an increasing interest in radiogenomic and characterization of DNA array molecular profiles that can predict the response to irradiation in tumor and non-tumor tissues. Now a technology of the short-term and inexpensive determination of indices aimed at an objectively based use of radiation therapy in experiment or clinic after evaluation of blood DNA radiosensitivity has been developed.

[Effects of iron ion additional introduction in radiation therapy of tumor-bearing animals]

The gender differences of the transplantable glioma-35 growth were revealed in tumor-bearing rats. The effect of mineral iron containing water (ICW) as drinking water was studied during radiation therapy (RT) in tumor bearing male rats. It was shown that ICW used separately had a weak anti cancer effect. The ICW use after irradiation caused no significant changes in hematological reactions as compared with RT only. The mineral water administration before irradiation resulted in the reduction of the supercoiled DNA index on the 1st and 21st day after irradiation, as well as in monocytopeny and a definite decrease in the tumor volume on the 21st day of the experiment as compared with control, which is associated with the ferroptosis effect of ICW. It was established that the reaction peculiarities of the blood DNA structure index in irradiated rats at the early stage of glioma growth may serve an express marker of the efficiency of RT.

[Comparative effects of difluoromethylornithine and tincture of Siberian ginseng root on radiation carcinogenesis and life span in rats]

Influence of alpha-difluoromethylornithine (DFMO) and tincture of Siberian ginseng root (TSGR) on radiation carcinogenesis and life span in rats has been studied. The results of the study demonstrate that DFMO as well as TSGR significantly improved survival and decreased incidence and multiplicity of malignant and benign tumors in rats subjected to ionizing radiation. Beneficial effect on the rat survival rate and anticarcinogenic action of DFMO were more expressed compared with TSGR.

[Inhibitory effect of bioginseng on radiation-induced carcinogenesis in rats]

Influence of bioginseng (biotechnological pharmaceutical drug from ginseng radix culture) on radiation-induced carcinogenesis has been studied. LIO female rats were divided into 3 groups. Rats of the first group (n=25) were used as intact control and weren't exposed to any influence. Rats of the second (n=50) and third (n=50) groups were exposed to single total body gamma-irradiation at a dose of 4 Gy. Animals of the 2nd group weren't exposed to any influence after irradiation, while animals of the 3rd group were given bioginseng with tap water (20 ml/l) until the end of study (438 days). In the control group 22,7% of animals developed tumors. In the 2nd group (irradiated control) 70% of animals were bearing multiple tumors one third of which were malignant. Mammary gland tumors were most frequent. Compared to the 2nd group the 3rd group receiving irradiation and bioginseng demonstrated the decrease in tumor incidence by 24.5% and 2,4 rate of decrease in tumors number. For the malign tumors was observed the decrease by 26.8% and 2,9 times, accordingly. For the mammary tumors the decrease was by 23.0% and 2,0 times, for mammary adenocarcinomas by 23.4% and 3,5 times, accordingly. The incidence and number of endocrine and reproductive organs tumors was 20,9% and 5,6 times, accordingly. Therefore, bioginseng effectively inhibits carcinogenesis induced by ionizing radiation in female rats.

[The influence of ferromagnetic screening from natural electromagnetic fields on the hematological and toxicogenomic indexes in animals]

The aim of the study was to reveal during 45 days consequences of ferromagnetic screening (FS) on the hematological and toxicogenomic indexes in rats. An express-method of nucleiod DNA content in blood by help fluorescent indication was used for alive quantitative evaluation of the toxicogenomic effects. The FS for both gender rats during 48 hrs resulted in both decreased magnetic field by 4-10 microT1 and leucopenia by 14 day of experiment. The aneu-/polyploidy index in male leucocytes was increased by 48 hr of FS and lasted out to 12-28 days after the screen removal. The leukocyte apoptosis was enhanced in female in 48 hrs only after the FS start.

[Effect of additional administration of ferric ion on the life span of irradiated animals]

There were established regularity of early biological reactions, restoration and life span shortening in rats after gamma-irradiation of animals with low (25 and 50 cGy) or 600 cGy doses in combination with various regimen of ferric ions introduction with drinking water (60-63 mg/l).

[Effect of additional administration of iron ions on the efficacy of radiotherapy of glioma-bearing animals]

Our analysis failed to establish any antitumor effect of treatment of rats with transplantable glioma-35 with iron-containing mineral drinking water (ICMW). The latter treatment combined with irradiation (15 Gy) was followed by enhanced genotoxic effect in white blood cells. Post-irradiation administration of ICMW did not influence glioma growth significantly as compared with radiation alone. Pre- and post-iradiation drinking of ICMW resulted in marked leukopenia 24 hrs after exposure as well as to significant decrease in tumor size (20-40 days after of experiment) as compared with control.

[Prediction of relapse-free period after radio- and chemotherapy in patients with breast cancer]

The study was carried out in 55 females with breast cancer stage III-IV, aged 35-77 yrs. The patients received radiation and standard courses of CMF, or CAF, or CMF+trastuzumab, or carboplatin+vepesid, or taxotere+epirubicin, or mustoforan. Radiation was administered in fractionated single focal doses of 3 Gy. S-index was determined before treatment started by an original short (ca. 4 hrs) method of evaluating apoptotic leukocyte DNA disintegration after ex vivo test irradiation as described by Ivanov S.D. et al., 2003. The index ranged 0.40-1.44 rel. units thus correlating with 2-100 month relapse-free period. Direct correlations were identified between S-index and relapse-free period for different regimens of radiochemotherapy. S-index level in excess of 0.95 involved relatively longer relapse-free survival. In summary, our method offers means of predicting the effectiveness of a particular regimen prior to treatment thus making individualization possible.

[Prognosis for therapeutic effectiveness of radiotherapy in the combined treatment of cancer]

The efficacy of radiotherapy and chemoradiotherapy for patients with breast cancer and combined treatment for bladder cancer was evaluated by means of as-blood test (Sbl). It points to magnitude of radiation-induced decay of peripheral blood DNA in vitro prior to therapy. Level of DNA decay was evaluated after exposure to 2Gy and 3-hr incubation. The index in excess of 1.0 (in radiation-sensitive patients) was followed by a relapse-free survival 1.5-2 times longer (5-32 months depending on pathology) than in radiation-resistant patients. Also, a relationship was established between Sbl index and leukopenia level, as an indicator of hematoxic effect of radio- and chemotherapy on patients with bladder cancer and Hodgkin's disease. Hence, Sbl may be used to individualize a therapeutic modality including radiotherapy and, if necessary, to provide for use of hemostimulators.

Comparative study of postradiation genotoxic changes in mammalian cells by biochemical and cytogenetic methods

The results of studying the genotoxic effect of radiation on endometrial cells of irradiated rats using comet assay correlated with the index of spontaneous DNA degradation. Studying the genotoxic effect of in vitro irradiation (2 Gy) on human lymphocytes by means of chromosome analysis and fluorometric assay of nucleoids DNA in irradiated leukocytes also yielded similar results. Measuring of the biochemical marker holds much promise as an express method of evaluation of the genotoxic effect of radiation on mammalian somatic cells.

[Effects of ligfol after radiation-mercury exposure in rats of various age]

The study was carried out with the young (4-5 months) and elderly (15-18 months) female and male rats at the experiment start. The mercury salt was administered into animals with drinking water in 1 mcg/l concentration during 3 months before and 1 month after single X-irradiation with 25 cGy dose. The genotoxic effects in leukocytes were evaluated on the base of the content and structure DNA alterations in 24 hrs and in 1 mth after irradiation. The alaninaminotransferase activity in serum was determined to evaluate functional status of liver. A protector intramuscular injection of Ligfol preparation with the 250 mg/kg dose in 24 hrs before irradiation resulted in increase of the blood leukocyte amount, more expressed in 1 mth after irradiation. The standardizing effect of preparation on the leukocyte DNA content is manifested in 1 mth after combined exposure on rats within young male and elderly female. At the same time, Ligfol showed some restoring effect on the alterations of leukocyte supercoiled DNA structure in 1 mth after irradiation within elderly female rats. The preparation showed the standardizing effect on the liver cells in young males injured by radiation-mercury exposures with low doses, however Ligfol had not influence practically on the destruction degree of hepatocytes after similar injury within female young and elderly rats. So, results of the intramuscular Ligfol injection is manifested at least during 1-2 mths; the young rats of both gender and elderly females showed the most sensitivity to the radiation-mercury exposure with low doses and to the Ligfol, according to the studied indexes.

[Effect of age and gender on genotoxic and biochemical indexes in animal blood after low doses of radiation-mercury exposures]

The study was executed with the young (4-5 months) and elderly (15-18 months) rats of both gender at the experiment start. The mercury salt was administered into animals with drinking water in 1 mcg/l concentration during 3 months before and 1 month after single X-irradiation with 25 cGy dose. The genotoxic effects in leukocytes were evaluated on the base of the content and structure DNA alterations in 24 hrs and in 1 month after irradiation. The alaninaminotransferase activity and the urea content in serum were determined to evaluate functional status of liver and kidney, respectively. The irradiation of rats receiving mercury with drinking water resulted in increase of the leukocyte DNA content in young male and decrease of the leukocyte quantity in young female at the early terms. At the same time the decrease of monocyte content and the alterations of the blood leukocyte DNA structure were observed in the elderly female. One month after combined exposures the whole leukocyte amount in young females was increased to the intact control level and the leukocytosis was observed in elderly females accompanied by significant condensation of the leukocyte DNA structure. At the same time granulocyte quantity was observed in young males in compare with the intact rats, and the tendency of the increased genotoxicity was lasted out. After combined exposures the functional liver alterations were observed in the highest degree among young male rats (+62%), in approximately identical degree among young and elderly females (+38% and +27%), and practically were absent among elderly males. The absence of the urea concentration increase in the serum of the all experimental group animals in comparison with the intact control rats evidenced, that lesion of kidneys did not take place. So, in despite of the fact that young females revealed sensitivity to the radiation-mercury environment exposure with the low doses in the early term, then they demonstrated the better restoration in compare with the young males and the elderly females. The elderly males were found the least sensitive to the radiation-mercury exposure with low doses among the studied animal groups.

Radiobiological effects of olipifat during radiation exposure

Preventive injections of olipifat to rats (intramuscularly in a single dose of 250 mg/kg 24 h before gamma-exposure in a dose of 7.6 Gy) decrease animal mortality from 70 to 50%, the mean life span of dead rats remained unchanged. Injection of olipifat before exposure in a dose of 5.2 Gy did not change animal mortality in comparison with irradiated controls, but stimulated postradiation recovery of leukocyte count (mainly the granulocytic component and less so the increase in lymphocyte count). No appreciable effects of olipifat on the postradiation changes in individual fractions of blood leukocytes were observed in animals exposed in a dose of 7.6 Gy.

[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.