[Impact of chemical surface treatment of samples made of domestic zirconium dioxide on adhesive strength]. / Vliyanie khimicheskikh metodov podgotovki poverkhnosti obraztsov iz otechestvennogo dioksida tsirkoniya na pokazateli adgezionnoi prochnosti.

Ceramic based on zirconium dioxide (ZD) is a modern, durable material for the manufacture of dentures. It is known that ZD is not etched as glass-ceramic, making it difficult to prepare this material before fixing. OBJECTIVE: To study the impact of various methods of surface treatment of ZD-based ceramic on adhesive strength. MATERIALS AND METHODS: Sandblasting with Al2O3 particles sized 50 µm and application of primers with 10-MDP phosphate monomer were used. Adhesive strength values for following 4 groups of samples were obtained: 1st group - RelyX U200 + sandblasting + Compofix new primer (n=9); 2nd group - Compofix + sandblasting + Compofix new primer (n=9); 3rd group - Panavia F 2.0 + sandblasting (n=9); 4th group (control) - Variolink Esthetic DC + sandblasting + Monobond Plus primer (n=9). RESULTS: The highest strength of adhesion was in the 4th group - 48.71±5.71MPa, the smallest in the 3rd group - 9.49±35.24 MPa. Fully domestic components used in the 2nd group allowed to obtain values of 42.50±9.79 MPa. Adhesive strength in the 1st group was 34.11±4.78 MPa. CONCLUSION: The absence of the 10-MDP-based primers application in the preparation of ZD ceramic reduces the adhesive strength between resin cement and its surface. The domestic set for fixation of dentures can be effectively used for ZD on the same basis as European analogue.

Search for Dark Photons with Superconducting Radio Frequency Cavities.

We conduct the first "light-shining-through-wall" (LSW) search for dark photons using two state-of-the-art high-quality-factor superconducting radio frequency (SRF) cavities -Dark SRF-and report the results of its pathfinder run. Our new experimental setup enables improvements in sensitivity over previous searches and covers new dark photon parameter space. We design delicate calibration and measurement protocols to utilize the high-Q setup at Dark SRF. Using cavities operating at 1.3 GHz, we establish a new exclusion limit for kinetic mixing as small as ε=1.6×10^{-9} and provide the world's best constraints on dark photons in the 2.1×10^{-7}-5.7×10^{-6} eV mass range. Our result is the first proof of concept for the enabling role of SRF cavities in LSW setups, with ample opportunities for further improvements. In addition, our data set a competitive lab-based limit on the standard model photon mass by searching for longitudinal photon polarization.

[Vascular inflammation underlies the development of atherothrombotic stroke]. / Sosudistoe vospalenie v osnove razvitiya aterotromboticheskogo insul'ta.

Atherothrombotic stroke is the one of the most common subtypes of ischemic cerebral circulatory disorders, the cause of which is atherosclerosis of the major arteries of the brain or their branches. The results of recent studies have shown that the atherosclerotic process is based on an inflammatory process in the vascular wall that leads to the initiation of atherosclerosis, endothelial dysfunction, oxidative stress, and the redistribution of various protein components in the blood-brain barrier. As a result, the progression of the described conditions leads to the manifestation of clinical symptoms and the formation of an acute vascular event. Understanding of the molecular components underlying functional disorders and damages of the cerebral vessels gives the key to modern therapy strategies. It is forming the foundation for the adequate, pathogenetically reasonable drug correction. For such patients, it should be aimed at the normalization of cerebral and central hemodynamics and incorporate the mechanisms of neuroplasticity. The drug 2-ethyl-6-methyl-3-oxypyridine-succinate (mexidol) can be considered as one of the pathogenetically justified agents in complex drug therapy of brain ischemia.

[Pathogenetic and therapeutic aspects of cardioembolic stroke]. / Patogeneticheskie i terapevticheskie aspekty kardioembolicheskogo insul'ta.

Cardioembolic stroke (CS) is the one of the most severe and requiring dynamic monitoring among the all subtypes of ischemic stroke. Patients with CS require joint treatment with cardiologists. CS is characterized by a greater severity of neurological deficits, a high risk of repeated acute cerebral circulatory disorders and fatal outcomes. This review considers the main causes of CS, the etiopathogenesis of thrombus formation in the heart chambers, current verification criteria and therapeutic aspects of CS, recommendations for the prescription of anticoagulant therapy for primary and secondary preventive treatment.

Indicators of chemiluminescent and bioluminescent tests of biological liquids in the assessment of physical health.

The study includes anthropometry of 172 young male, obtained data on the length and body mass, measured the transverse diameters of the shoulders and pelvis, various body types was identified by the J.M. Tanner sexual dimorphism index (andromorphic, mesomorphic, gynecomorphic). The chemiluminescent and bioluminescent study of saliva and blood was conducted in the examined young male. We studied the indicators of the antioxidant defense system under the influence of stress. The antioxidant status of saliva was determined using the H2O2-luminol-dependent chemiluminescence method. Data on the activity of NAD (P) -dependent dehydrogenases in blood lymphocytes was obtained from a bioluminescent method of research. Young male of andromorphic body type had large overall and transverse body sizes. Indicators of antioxidant protection of saliva and blood in men of adolescence, the body type of the sexual dimorphism index J.M. Tanner was different. The persons of the andromorphic body type differed in terms of chemiluminescence in comparison with the young male of gynecomorphic body type. The results of bioluminescent blood tests suggest a violation of the catabolic and anabolic processes of carbohydrate and fat metabolism in young men of mesomorphic and gynecomorphic body types. Indicators of the system of antioxidant protection of saliva and blood reflect the sexual characteristics of the body of young male and can be used as additional criteria for diagnosing sex inversion and assessing the risk of developing socially attributed diseases.

EPIDEMIOLOGY OF BREAST CANCER IN UKRAINE WITH CONSIDERATION OF THE FACTORS OF THE CHORNOBYL ACCIDENT. / EPIDEMIOLOGIIa RAKU MOLOChNOÏ ZALOZY V UKRAÏNI Z URAKhUVANNIaM FAKTORIV RYZYKU ChORNOBYL'S'KOÏ AVARIÏ.

OBJECTIVE: Assessment of the possible impact of the Chornobyl accident on the incidence of breast cancer in the female population of Ukraine as a whole and in some affected groups. OBJECT OF THE STUDY: The female population of Ukraine as a whole and in separate groups of victims - women par- ticipating in the clean-up works in 1986-1987, evacuaees from the exclusion zone and inhabitants of the territo- ries most contaminated with radionuclides. METHODS: Statistical, mathematical, cartographic. RESULTS: This study, covering a significant period of time (1976-2016), revealed a steady temporal and territorial agglomeration of regions with a higher incidence of breast cancer in the southern and south-eastern regions of Ukraine. Lower - in the western and northern regions. There is a steady increase in the incidence rate, but in recent years this growth has slowed down. The epidemiological situation regarding the incidence of breast cancer in the female population of Ukraine during the 30 years after the Chornobyl accident is generally stable. At the same time, a marked increase in the frequency of this pathology in the groups of the affected population, especially in women, participated in clean-up works in 1986-1987. CONCLUSIONS: A stable agglomeration of regions with high levels of incidence in the south and south-east, and low in the west and north of the country is determined. The dynamics of breast cancer in Ukraine as a whole is characterized by steady growth, although in recent years its pace has slightly decreased. Among the individual population groups affected by the Chornobyl catastrophe (female liquidators, evacuated women from the exclusion zone, residents of the most contaminated with radionuclides territories) only among female liquidators of 1986-1987 the significant in- crease was observed in the incidence of breast cancer, which exceeds the national indicators at 1.3-1.6 times.

Моlecular mechanisms of initiation of carcinogenesis in the testis.

In this review, literature data on the study of precancerous changes in testicular tissue and molecular changes, as well as the influence of environmental factors that can initiate carcinogenesis, were analyzed and summarized for the future determination of early diagnosis of germ cell tumors of the testis and the development of preventive measures. The review also discusses the significant new changes presented in the Fourth Edition of the World Health Organization Classification of Urogenital Tumors, published in 2016, and modern concepts of the etiology and pathogenesis of these diseases. Among the environmental factors that can initiate carcinogenesis, the most noteworthy are the biological effects of low doses of ionizing radiation, such as the effect of radiation-induced genome instability, which increases the risk of carcinogenesis, the "bystander effect", and chronic oxidative stress. Disruption of ubiquitin-proteasomal proteolysis, impaired molecular-level components of the blood-testis barrier, and impaired regulatory action of TGF-ß on the cell cycle can play a crucial role in the pathogenesis of male infertility and the initiation of carcinogenesis in the testis. The effect of low doses of ionizing radiation as an additional etiological factor leads to changes in the structural, as well as molecular, components of the testis, including epigenetic changes, which can be characterized as environmental pathomorphosis, which leads to impaired spermatogenesis and increased risk of malignancy. Summarizing the literature review data, we can state that patients with blocked spermatogenesis, in which atypical germ cell neoplasia in situ cells are detected in testicular tissue, constitute a group at increased risk of testicular carcinogenesis. The presence of additional etiological factors, such as chronic low doses of ionizing radiation, can initiate the progression of carcinogenesis in the testicle.

RADIATION RISKS OF THYROID CANCER IN CHORNOBYL CLEAN-UP WORKERS USING THE ALTERNATIVE ESTIMATES OF DOSES OF EXTERNAL EXPOSURE. / RADIATsIINI RYZYKY RAKU ShchYTOPODIBNOÏ ZALOZY V UChASNYKIV LIKVIDATsIÏ AVARIÏ NA ChAES Z URAKhUVANNIaM AL'TERNATYVNYKh OTsINOK DOZ ZOVNIShN'OGO OPROMINENNIa.

OBJECTIVE: The objective of this study was to estimate the thyroid cancer radiation risks - excess absolute risk(EAR), excess relative risk (ERR) and attributable fraction of risk (AR) in the cohort of 150,813 Ukrainian male clean-up workers during the 1986-2012 period (more than 25 years after the Chornobyl accident). MATERIALS AND METHODS: The cohort under study of 150,813 Ukrainian men who participated emergency and clean-up work in 1986-1990 was formed based on the data of the Ukrainian State Register of persons affected due toChornobyl accident (SRU). The identification of thyroid cancer cases (216) was carried out by linking the SRU data-base with the National Cancer Registry of Ukraine (NCRU) data. Standardised incidence ratios (SIR) were estimatedcomparing thyroid cancer incidence in the cohort with the corresponding national indices. Excess absolute risk(EAR), excess relative risk (ERR) and attributable fraction of risk (AR) were calculated accounting for the alterna-tive dose estimates. The following sources of the average dose values for Ukrainian liquidators were used: officialtotal external dose records according to UNSCEAR 2008 report and results of external red bone marrow dose recon-struction by the RADRUE method for the cohort sample. For the radiation risk evaluation, these estimates were con-versed to the average external thyroid dose. RESULTS: Results of the long term study (1986-2012) of thyroid cancer risks in a cohort of 150813 Chornobyl clean-up workers («liquidators¼) from Ukraine are presented. Two options for the average thyroid dose estimates were usedfor radiation risks evaluation. According to the SRU and NCRU 216 incident thyroid cancers were diagnosed in 1986-2012 within the studied cohort with an overall SIR of 3.35 (95 % confidence interval (CI) 2.51-3.80). The SIR esti-mates were elevated throughout the entire follow-up period. Investigation of a contribution of the external expo-sure (according to the alternative values) showed the elevated dose associated thyroid cancer rates in the studiedcohort. Alternatively estimated EAR/104 PY Gy were of 1.86 (95 % CI 0.47-3.24) and 2.07 (95 % CI 0.53-3.62);ERR/Gy - 2.38 (95 % CI 0.60-4.15) and 2.66 (95 % CI 0.68-4.64) and AR % (Gy) 70.4 % and 72.7 % Gy. CONCLUSIONS: Obtained results prove the dose dependent increase of thyroid cancer incidence among UkrainianChornobyl clean-up workers. These conclusions are consistent with those received for combined cohort of Belarus,Russia and Baltic States liquidators.

Field-Enhanced Superconductivity in High-Frequency Niobium Accelerating Cavities.

The discovery of nitrogen-doping treatment revealed that the radio frequency surface resistance of niobium resonators may be significantly reduced when nitrogen impurities are dissolved as interstitials in the material. A peculiar behavior exhibited by N-doped cavities is the anti-Q slope, i.e., a reduction in the temperature-dependent component of the surface resistance as a function of the accelerating field. This unusual trend in the surface resistance behavior has been attributed to the presence of interstitial nitrogen in the niobium lattice after the doping treatment. This Letter presents a focused study on the field dependence of the temperature-dependent component of the surface resistance as a function of the cavity resonant frequency. The findings show that the anti-Q slope may appear even in clean niobium cavities if the resonant frequency is high enough, which suggests new routes toward understanding the anti-Q slope effect.

Calcium as a Modulator of the Adenylyl Cyclase Activity of Potato Cells in Bacterial Pathogenesis.

This is the first study to detect the effect of calcium ions on the activity of transmembrane adenylyl cyclase (tmAC), the key enzyme of the adenylyl cyclase signaling system, under normal conditions and after a short-term exposure to exopolysaccharides (EPS) of the bacterial ring rot pathogen Clavibacter michiganensis ssp. sepedonicus (Cms). After the treatment of the roots of plants with the Cms EPS, the response to Ca2+ changed: the activity of the tmAC of plants of the resistant cultivar significantly increased, whereas in the cells of the susceptible cultivar it remained unchanged.

Understanding Quality Factor Degradation in Superconducting Niobium Cavities at Low Microwave Field Amplitudes.

In niobium superconducting radio frequency (SRF) cavities for particle acceleration, a decrease of the quality factor at lower fields-a so-called low field Q slope or LFQS-has been a long-standing unexplained effect. By extending the high Q measurement techniques to ultralow fields, we discover two previously unknown features of the effect: (i) saturation at rf fields lower than E_{acc}∼0.1 MV/m; (ii) strong degradation enhancement by growing thicker niobium pentoxide. Our findings suggest that the LFQS may be caused by the two level systems in the natural niobium oxide on the inner cavity surface, thereby identifying a new source of residual resistance and providing guidance for potential nonaccelerator low-field applications of SRF cavities.

[The use of the gender dimorphism index of J. Tanner for assessing the physical state of older women].

Assessment of the physical status of older women conducted anthropometry and bioimpendance analysis. Body type determined by the gender dimorphism index of J. Tanner (1951). It was found that in the studied sample representative of gynecomorphic and mesomorphic body types were determined in a high percentage of cases: 46,15 and 49,11 %. Women andromorphic body type were found less frequently - 4,74 %. Women with gynecomorphic body type were smaller mass and transverse dimensions of the body, unlike representatives with andromorphic and gynecomorphic body types. The absolute content of fat and lean body mass tended to increase from gynecomorphic body types representatives to andromorphic. The results of anthropometric measurements, bioimpedance analysis and determined by the gender dimorphism index of J. Tanner provide results about adaptive possibilities the human body and can serve as markers (predictors) of somatic diseases.

Incidence of multiple myeloma among cleanup workers of the Chornobyl accident and their survival.

The study presents the updated data on the multiple myeloma (MM) incidence in Ukrainian cleanup workers after the Chornobyl accident and their survival. The epidemiological analysis is based on the extended follow-up period to identify new MM cases for higher statistical power and to collect additional data on the disease course and outcome for the survival analysis. The objective of the study was to analyze the MM incidence and survival in Chornobyl cleanup workers in 1996-2013 in comparison with the national MM statistical data. MATERIALS AND METHODS: A study cohort consisted of 152,520 male cleanup workers resided in one of 6 regions of Ukraine or Kyiv city and registered in the Ukrainian State Chornobyl Registry (SChR). The Cohort Database was linked to the Ukrainian National Cancer Registry (NCR) Database to identify MM cases and to analyze MM incidence in 1996-2013. Standardized incidence ratios (SIR) for MM over the period 1996-2013 were calculated as compared to the general population of Ukraine. A 10-year lag period (when incident cases are not considered radiation-related) was applied. One-year and 5-year cause-specific survival of MM cases were calculated as percentage of those who were alive correspondingly for 1 or 5 years after diagnosis among overall diagnosed. By the moment, the 5-year survival rate either for the sub-period 2008-2013 or for the whole study period 1996-2013 cannot be determined. Vital status data were updated according to the recent SChR and NCR information. RESULTS: 75 MM cases diagnosed in 1986-2013 were identified in the studied cohort. 69 of them were included to the incidence analysis considering a 10-year lag period. While the incidence over 15 years after the accident did not differ significantly from the corresponding rate in general population of Ukraine, a tendency to increase was seen in the period from 16 to 21 years after the accident, and significantly increased SIR estimate was revealed for 2008-2013 (SIR 1.86, 95% confidence interval (CI) 1.27-2.44). The highest incidence was detected in 2008-2013 among cohort members diagnosed over the age of 50 years mostly due to the significant excess among those aged 60-69 (SIR 2.46, 95% CI 1.32-3.59). Survival rates in cleanup workers were shown to be higher than in the general population of Ukraine (73.9% and up to 65.0%, respectively). CONCLUSIONS: SIR for the 2008-2013 period, 22-27 years after the accident, demonstrated the significant excess of MM incidence among male cleanup workers. Survival of MM cases is higher in cleanup workers in comparison with that in general population. This article is a part of a Special Issue entitled "The Chornobyl Nuclear Accident: Thirty Years After".

[Effect of N-phenyl-2-naphthylamine on activity of adenylate cyclase signal system components and virulence of bacterial phytopathogens and mutualists].

The effect of N-phenyl-2-naphthylamine, negative allelochemical isolated from the exudates of roots of pea (Pisum sativum L.), on the growth and activity of the adenylate cyclase signal system and virulence factors of the bacteria Rhizobium leguminosarum bv. viciae and Pseudomonas siringae pv. pisi was studied. It was demonstrated that N-phenyl-2-naphthylamine at a physiological concentration nonspecifically inhibited the growth of these bacteria in both planktonic cultures and biofilms. One of the reasons for this phenomenon is the reduction of intra- and extracellular concentrations of cAMP due to greater activation of phosphodiesterase, which disrupts cAMP, in comparison to soluble adenylyl cyclase, which synthesizes it. At the same time, N-phenyl-2-naphthylamine did not affect activity of either membrane-bound adenylyl cyclase or bacterial virulence factors.

[IMMUNOHISTOCHEMICAL EXPRESSION OF UBIQUITIN PROTEIN IN PERITUMORAL TISSUE OF PATIENTS WITH TESTICULAR GERM CELL TUMORS].

For the purpose of definition of features immunohistochemical expression of protein Ubiquitin in peritumoral testicular tissue, which can be characterised as precancerous changes, the 40 patients with testicular germ cell tumors are investigated. In peritumoral testicular tissue in patients with disturbance of spermatogenesis. which make 95 %, it is taped: intensifying in seminiferous tubules of ubiquitination processes, testifying about intensive proteolysis of considerable quantity of the damaged intracellular proteins, occurrence of atypical germ cells (TIN), which differ from normal spermatogenesis cells authentically lower of nuclear and cytoplasmatic expression of protein Ubiquitin, and also disturbance of ubiquitination processes in Leydig cells in the form of intensifying of cytoplasmatic expression and total disappearance of nuclear expression of protein Ubiquitin. The received results testify to the important role of structural and functional disturbances of ubiquitin-proteolysis system components at the initial stages of testicular tissue carcinogenesis.

Quarter of century since the Chornobyl accident: сancer risks in affected groups of population. / Chvert'' stolittja pislja Chornobyl''s''koi' avarii': ryzyk raku v grupah postrazhdalogo naselennja.

Objective. The goal of this study was to define levels and dynamic trends of cancer incidence at whole and some separate sites in groups of Ukrainian population affected by the Chornobyl accident during a long period of observation. Materials and methods. Those groups were Chornobyl accident recovery operation workers (CRW) of 1986-1987 years of participation, evacuees from Prypyat town and 30-km zone and residents of the most contaminated territories of Ukraine. Analysis was carried out with the standard methods of descriptive epidemiology: calculation of crude, age-specific and age-adjusted incidence rates with standard errors and confidence intervals. Results, discussion and conclusions. This study showed that all cancer incidences exceeded the national level only in CRW group. Decrease of cancer incidence rate in the recent years might be caused by shortened average life expectancy in Ukrainian population, especially in males. Statistically significant increase of leukemia incidence in CRW group was registered as well. Besides, in all three main affected groups there was revealed significant excess of thyroid cancer. Irradiation of thyroid due to radioactive iodine fallouts might be a main cause of this phenomenon. Increase of thyroid cancer incidence was registered not only in children, but also in adolescents and adults. Appearance of excess thyroid cancer cases as an effect of radiation exposure tends to increase during the time. Significant excess was also revealed for breast cancer in female CRW group. Because latency period for different nosological forms of radiation-induced malignant tumors varies widely, profound attention in further studies should be drawn not only to thyroid, breast cancers and leukemia, but also to malignancies with longer latent period: lung, stomach, colon, ovary, urinary bladder, kidney cancer and multiple myeloma.

[Picocyanobacteria in eutrophic reservoirs of the Middle Volga: abundance, production, viral infection].

During the summer season of 2010, abundance and productivity of picocyanobacteria in Gorky and Cheboksary Reservoirs have being examined. It is found out that in the eutrophic reservoirs of the Middle Volga abundance and biomass of picocyanobacteria, averaged over the water column, varied within the range of (34-322) x 10(3) cells/ml and 38-455 mg/m3 respectively. In more productive Cheboksary Reservoir, the contribution of picocyanobacteria in total biomass and production of phytoplankton (4.7 ± 0.7 and 8.3 ± 1.3% respectively) was lower than in less productive Gorky Reservoir (10.6 ± 2.1 and 19.2 ± 3.0% respectively). In both reservoirs, high level of picocyanobacteria infection by viruses was detected. The frequency of visible infected cells and virus-induced mortality of picocyanobacteria in Cheboksary Reservoir were substantially higher (3.2 ± 0.4% of total abundance and 21.8 ± 2.9% of daily production) than in Gorky Reservoir (1.7 ± 0.2% of total abundance and 11.0 ± 1.7% of daily production). The results obtained indicate that in eutrophic reservoirs during summer bloom of large cyanobacteria their abundance is regulated to a great extent by viruses.

Error analysis for intrinsic quality factor measurement in superconducting radio frequency resonators.

In this paper, we discuss error analysis for intrinsic quality factor (Q0) and accelerating gradient (Eacc) measurements in superconducting radio frequency (SRF) resonators. The analysis is applicable for cavity performance tests that are routinely performed at SRF facilities worldwide. We review the sources of uncertainties along with the assumptions on their correlations and present uncertainty calculations with a more complete procedure for treatment of correlations than in previous publications [T. Powers, in Proceedings of the 12th Workshop on RF Superconductivity, SuP02 (Elsevier, 2005), pp. 24-27]. Applying this approach to cavity data collected at Vertical Test Stand facility at Fermilab, we estimated total uncertainty for both Q0 and Eacc to be at the level of approximately 4% for input coupler coupling parameter ß1 in the [0.5, 2.5] range. Above 2.5 (below 0.5) Q0 uncertainty increases (decreases) with ß1 whereas Eacc uncertainty, in contrast with results in Powers [in Proceedings of the 12th Workshop on RF Superconductivity, SuP02 (Elsevier, 2005), pp. 24-27], is independent of ß1. Overall, our estimated Q0 uncertainty is approximately half as large as that in Powers [in Proceedings of the 12th Workshop on RF Superconductivity, SuP02 (Elsevier, 2005), pp. 24-27].

[Heterotrophic organisms and viruses in the Oka River and Cheboksary Reservoir during the abnormally hot summer of 2010].

In July 2010, abnormally high water temperature (25-29 degrees C), as well as increased biomass and phytoplankton production caused intensive development of heterotrophic bacteria and heterotrophic nanoflagellates. It was found that the abundance, biomass, and production of heterotrophic bacterioplankton, as well as the abundance and biomass of heterotrophic nanoflagellates, and the number of planktonic viruses, which were calculated on average for the reservoir under study, turned out to be higher in the years with lower water temperature (20-23 degrees C). The virus-induced mortality of bacterioplankton in the Oka River and the Cheboksary Reservoir averaged 25.4 +/- 3.4 and 22.4 +/- 2.7% of the daily bacterioplankton production.

Age and gender patterns of thyroid cancer incidence in Ukraine depending on thyroid radiation doses from radioactive iodine exposure after the Chornobyl NPP accident.

UNLABELLED: The objective of this study was to investigate the thyroid cancer incidence in a whole territory of Ukraine and to clear up its age and gender patterns depending on average regional (oblast) thyroid doses from radioactive iodine due to the Chornobyl accident. MATERIALS AND METHODS. On the basis of average accumulated thyroid doses from radioactive iodine the geographical regions of Ukraine with low and high average thyroid doses were identified for a comparative analysis performance. Methods of descriptive epidemiology were used. RESULTS: The level and dynamics of thyroid cancer incidence were analyzed in different gender and age groups (both for attained age and age at the moment of the Chornobyl accident). Results of this study confirmed the radiation excess of thyroid cancer in individuals who were children and adolescents in 1986. Some excess was observed in elder age groups too. Especial situation was observed in female age group 40-49 at the moment of the Chornobyl accident i.e. the age-specific thyroid cancer incidence rates were significantly higher in "high exposure" regions comparing with "low exposure" ones during all years of observation within 1989-2009. CONCLUSIONS: A probable radiation excess of thyroid cancer was suggested not only in children and adolescents but also in adult age groups. In elder age groups this excess was less expressed and manifested after a longer period of time. The origin of the phenomenon in female age group of 40-49 is unclear now. Hypothesis of combined effect of radiation and natural changing of hormonal status in this age should be checked in the future studies.