THE COURSE OF CHRONIC LYMPHOCYTIC LEUKEMIA AFTER SARS-COV-2 VIRUS INFECTION

Objective - to investigate the course of B-cell chronic lymphocytic leukemia (CLL) in patients after SARS-CoV-2 virus infection taking into account anamnestic exposure to the ionizing radiation (IR).Methods. The study was performed in a group of 51 CLL patients who were admitted to the Department of Radiation hematology of the National Research Center for Radiation Medicine of NAMS of Ukraine, Kyiv, from January 2020 (the beginning of SARS-CoV-2 epidemic) to August 2023. The group included 19 (37.3 %) clean-up workers of the Chornobyl NPP accident, 15 (29.4 %) inhabitants of radionuclide contaminated areas and 17 (33.3 %) IR non-exposed patients. The diagnosis of CLL was based on clinical history, lymphocyte morphology, and immunophenotypic criteria. Statistical studies were performed using the SPSS software package, version 20.0.Results. The diagnosis of CLL was established for the first time in 14 patients, in seven of them, CLL was diagnosed after 2-17 months after SARS-CoV-2 infection. In contrast to patients who did not suffer from a coronavirus infection, they had pronounced lymphadenopathy, which in some cases was accompanied by hyperleukocytosis, and needed early treatment. Thirteen patients with a previously established CLL were diagnosed with COVID-19 by PCR test. In seven of them (53.8 %) starting treatment was needed, or CLL has progressed. Seven of 51 patients (13.5 %) were vaccinated against SARS-CoV-2. Then, four of them were diagnosed with SARS-CoV-2 infection, confirmed by a positive PCR test, and two patients had a relapse of CLL within 1-2 months after vaccination. Most of patients with signs of the influence of SARS-CoV-2 infection on CLL belonged to sufferers of the Chornobyl NPP accident Conclusions. The clinical features of CLL that developed after SARS-CoV-2 were characterized firstly. The negative impact of SARS-CoV-2 infection on previously established CLL was established. The question about vaccination of CLL patients remains debatable.

REVIEW OF THE NATURE OF ANTI/INFLAMMATORY AND PRO-INFLAMMATORY CYTOKINE REGULATION IN DIFFERENT PERIODS OF PLASMA CELL MYELOMA NATURAL HISTORY IN THE CHORNOBYL NPP ACCIDENT SURVIVORS

OBJECTIVE

identify the nature of anti-inflammatory and pro-inflammatory cytokine regulation in different periods of plasma cell myeloma (PCM) natural history with evaluation of its role as a prognostic criterion for the disease course in the Chornobyl NPP (ChNPP) accident survivors.

MATERIALS AND METHODS

Levels of pro-inflammatory (IL-6, TNF-α) and anti-inflammatory (IL-10) cytokines both with their relationship were studied in the stage I-II and stage III PCM patients (n = 74) in different periods of the disease natural history i.e. remission/stabilization and progression. Study groups included the ChNPP accident survivors (n = 35) and non-irradiated subjects (n = 39). Immunoenzymatic method was applied using the Vector-Best CJSC commercial kits.

RESULTS

There was a unidirectional increase in the levels of IL-6, TNF-α, and IL-10 in irradiated persons, and an elevation of IL-6 and TNF-α concentration but with a decreased level of IL-10 in non-irradiated subjects compared to control at the time of PCM diagnosis. Period of the disease remission/stabilization in PCM stage I-II patients featured a decrease in IL-6 concentration regardless of the exposure to ionizing radiation, while TNF-α content remained at the level of the control group. There was a significant increase in IL-6 concentration in both study groups during the disease relapse, while TNF-α level remained unchanged compared to stabilization phase of the disease. According to the obtained data a certain contribution of radiation exposure to the PCM pathogenesis as a possible predictor of the exacerbated disease course cannon be excluded.

CONCLUSION

Determining the serum level of pro-inflammatory and anti-inflammatory cytokines (IL-6, TNF-α and IL-10 respectively) provides advancement in assessment of the PCM course and predict the effectiveness of administration of therapy protocols.

STEREOTYPED CASES IN UKRAINIAN COHORT OF CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS DEPENDING ON THE IONIZING RADIATION EXPOSURE

OBJECTIVE

to analyze the stereotyped subsets in cohort of Ukrainian chronic lymphocytic leukemia (CLL) patients in general and depending on the ionizing radiation (IR) exposure.

METHODS

Analysis was performed in the groups of 118 CLL patients irradiated due to the Chornobyl NPP accident (95 clean-up workers, 17 inhabitants of radionuclide contaminated areas, and 6 evacuees) and 294 IR non-exposed patients. The IGHV (immunoglobulin heavy chain variable region) gene mutational status, mutations of NOTCH1, TP53 and SF3B1 genes were studied by polymerase chain reaction followed by direct sequencing. Associations between clinical and molecular data of patients were analyzed with the SPSS software package, version 20.0.

RESULTS

The incidence of stereotyped CLL cases in Ukrainian cohort was high (50.5 %) and comparable in IR-exposed and non-exposed patients. The ratio of major and minor clusters as well as the frequency of individual clusters was comparable with reported data with some exceptions: a low incidence of subset #2; absence of subset #8; high frequency of minor subset #V4|J4.5.6|18|5. The distinctive features of IR-exposed CLL patients found were:1) comparable frequency of stereotyped cases among mutated and unmutated (UM) IGHV genes cases (p = 0.557);2) lack of differences IGHV gene repertoires among stereotyped and heterogeneous cases (p = 0.508); 3) «heterogeneity» of stereotyped cases: all identified stereotyped clusters, with the exception of cluster #1, consisted of one case. Stereotyped cases with expression of UM IGHV clan I genes (except IGHV1-69 gene) were more susceptible to the appearance of NOTCH1 mutations. Patients of cluster #4 were younger, tended to have a longer time-to-treatment period and overall survival (OS) compared to subset #2. Patients of cluster #2 are more likely to have autoimmune hemolytic anemia (AIHA) and SF3F1 mutations. IGHV3-21 expression was associated with worse OS in univariate and multivariate analysis. AIHA was more common in patients with UM IGHV4-59 and IGHV3-11 genes.

CONCLUSIONS

The revealed differences in distribution of stereotyped CLL cases in Ukrainian cohort are most likely to reflect variations in the genetic background, environmental factors (including IR exposure), and their interactions in different geographic areas.

COMPLEX ANALYSIS OF THE ROLE OF CYTOKINE GENE POLYMORPHISMS AS PROGNOSTIC FACTOR OF THE RISK OF PLASMA CELL MYELOMA IN PERSONS SUFFERED AFTER THE CHORNOBYL NPP ACCIDENT

OBJECTIVE

to provide a comparative characterization of the prevalence of polymorphic variants of cytokine genes in plasma cell myeloma (PCM) patients suffered after the Chornobyl disaster and patients who were in contact with ionizing radiation within the natural radiation background, based on comparison with population controls to determine their contribution as genetic markers of disease risk.

MATERIALS AND METHODS

Molecular genetic studies of polymorphism of cytokine genes (TNF-α, TGF-β1, IL-6, IL-10, IFN-γ) and complex frequency analysis of occurrence in three-, four-, and five-locus combinations of their allelic variants as prognostic markers of the risks of plasma cell myeloma was carried out in 102 patients - 56 victims of the Chornobyl nuclear power plant accident and 46 patients irradiated within the limits of the natural radiation background, in comparison with the control group (364 practically healthy people, residents of the Central geno-geographical region of Ukraine).

RESULTS

The same probable increase in the prevalence of the TGF-β genotype codon10 T/T of the TGF-β1 gene was established in the groups of patients irradiated after the Chornobyl NPP accident and non-irradiated patients. In patients with plasma cell myeloma a protective effect for IL-10 -1082 A/G and an association with the risk of disease occurrence for IL-10 -1082 G/G were determined.

CONCLUSION

Probable difference in the frequency of the TGF-β1 genotype codon10 T/T of the TGF-β1 gene in the observed groups relative to the control group provides grounds for considering this single-nucleotide polymorphism of the TGF-β1 gene as an immunogenetic factor of predisposition to the development of PCM independent of exogenous factors. The study of the contribution of multigene combinations of «gene-gene» interaction indicates their role in the mechanisms of plasma cell myeloma occurrence and confirms the presence of an additive interaction.

THE EXPRESSION OF THE MAIN AND ALTERNATIVE TRANSCRIPT (SORL1 Delta2) OF THE SORL1 GENE IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS AFFECTED BY THE CHORNOBYL ACCIDENT

OBJECTIVE

to study clinical-hematological data and expression of the main and alternative transcripts of SORL1 genein chronic lymphocytic leukemia (CLL) patients affected by the Chornobyl catastrophe.

METHODS

Analysis was performed in the main group of 34 CLL patients irradiated due to the Chornobyl NPP acci-dent (30 clean-up workers, and 4 evacuees) and in the control group of 27 non-irradiated CLL patients. Groups ofpatients were comparable by age, sex, stage of disease, mutational status of IGHV genes. Expression of the main andalternative transcripts of SORL1 gene was evaluated by Quantitative Real-time polymerase chain reaction (PCR). TheIGHV gene mutational status, TP53 and SF3B1 mutations were studied by PCR followed by direct sequencing. Data wereanalyzed with the SPSS software package, version 20.0.

RESULTS

Relative expression level of the main transcript of SORL1 gene was low (mean 1.71 ± 0.55, median 0.57),did not correlate with the IGHV gene mutational status, TP53 and SF3B1 mutations, stage of disease. The expressionof B transcript was not detected, F transcript was expressed at a very low level in 9 patients. The average relativeexpression level of SORL1-Δ2 transcript was 14.1 ± 6.04 (median 3.48; range 0.01-90.51). The expression of SORL1-Δ2transcript above the median was more frequent among patients on C stage (p = 0.001), and in patients with unmu-tated IGHV genes was associated with an extremely negative course of CLL (median of overall survival 9 months vs61 months at low expression). Relative expression levels of the main and alternative transcripts of SORL1 gene inpatients of the main and the control groups did not differ.

CONCLUSIONS

Our preliminary data suggest that increased expression of SORL1-Δ2 transcript in CLL patients withunmutated IGHV genes can be considered as a negative prognostic marker.

LONG/TERM GENETIC AND EPIGENETIC DISORDERS IN PERSONS EXPOSED TO IONIZING RADIATION AND THEIR DESCENDANTS (review)

The review is devoted to long-term genetic and epigenetic disorders in exposed individuals and their descendants,namely to cytogenetic effects in the Chornobyl NPP accident clean-up workers and their children, DNA methylation as an epigenetic modification of human genome. Data presented in review expand the understanding of risk of the prolonged exposure for the present and future generations, which is one of key problems posed by fundamental radiation genetics and human radiobiology.

CYTOGENETIC INDICATORS OF ACUTE RADIATION SICKNESS (THE CHORNOBYL EXPERIENCE)

The objective of the study was to improve the biological dosimetry approach among patients with acute radiationsickness of various degrees based on the analysis of radiation-induced chromosome aberrations in peripheral bloodlymphocytes of the victims.

MATERIALS AND METHODS

The study was based on primary cytogenetic data obtained in May 1986 within examina-tion of the 30 clean-up workers («liquidators») having got stage I-III acute radiation sickness. Dose verificationwas performed using the cytogenetic dosimetry based on a culture of peripheral blood lymphocytes with metaphaseanalysis of chromosome aberrations.

RESULTS

A new method of evaluating the results of patients' cytogenetic examination at the beginning of specifictherapy has been developed. Procedure was performed using a model of multiple linear regression (complex of cyto-genetic parameters) and provided a satisfactory diagnostic level (featuring a compliance with initially definedclinical and laboratory diagnoses). Overall frequency of the aberrant cells and radiation markers increased in high-er disease stages. There was a trend of the frequency growth of chromatid-type aberrations with increasing of radi-ation burden. Adequacy of the proposed method based on the regression analysis of cytogenetic results was con-firmed through the preservation of group differences in estimates of disease stage in subjects with verified diagnosis.

CONCLUSION

Cytogenetic dosimetry in the scope of examination of persons exposed to ionizing radiation is an oblig-atory component of radiation sickness stage verification. The recommended method of cytogenetic data evaluationbefore and at the beginning of detoxification therapy provides a satisfactory level of diagnostics.

ODONTOLOGICAL EFFECTS OF IONIZING RADIATION (review)

BACKGROUND

Odontological effects of ionizing radiation (IR) as a result of radiotherapy, the consequences of accidents at nuclear power plants and industry, individual occupational exposure, etc. deserve significant attention interns of radiation medicine and radiation safety.

OBJECTIVE

to analyze and summarize clinical and experimental data on the odontological radiation effects.

MATERIALS AND METHODS

OBJECT

the pathological changes in the hard tissues of teeth, pulp, periodontium, mucousmembranes of the mouth and jaws due to exposure to IR.

METHOD

search in the PubMed / MEDLINE, Google Scholarabstract medical and biological databases, scientific libraries of the relevant sources of scientific information.

RESULTS

Radiobiological effects of IR due to its direct and indirect action are manifested throughout the period ofodontogenesis and formation of the facial skeleton. Experimental and clinical data (in children and adults) indicatethe increased risk of dental caries, reduction of pain threshold and vascularization of tooth pulp along with its fibrosis and atrophy, periodontal dysfunction, which predispose to a high probability of tooth loss. Abnormalities in theactivity of osteoblasts and cementoblasts of dental periosteum and osteoblasts of alveolar process in combinationwith circulatory disorders due to endothelial cell death, hyalinization, thrombosis and vascular obliteration increasethe risk of jaw osteoradionecrosis. Children who have undergone a prenatal exposure to IR as a result of theChornobyl NPP accident have a premature change of teeth. Deterioration of periodontal tissues and early development of acute and complicated dental caries are typical for children and adults affected by the Chornobyl disaster.

CONCLUSIONS

Summarized data on the effects of radiation exposure under different conditions on teeth primordia(i.e. immature teeth), their formation and eruption in experimental and clinical settings, as well as on the odontological radiation effects in adults are summarized. Condition of the teeth in the Chornobyl NPP accident survivorsis described. Understanding and taking into account the radiobiological odontological effects is necessary in thelight of planning, preparing, and conducting local radiation therapy and developing the standards of radiation safety and measures to protect professionals and the public in the event of possible radiation accidents at the nuclearpower plants and industry facilities.

INCIDENCE OF MALIGNANT NEOPLASMS AMONG RESIDENTS OF SMALL RADIONUCLIDE-CONTAMINATED CHORNOBYL DISTRICTS IN A POST-ACCIDENT PERIOD

OBJECTIVE

To assess the level of risks of development of malignant neoplasms among the residents of smallChornobyl districts («rayons») in connection with low-dose radiation exposure and its dynamic changes.

MATERIALS AND METHODS

The study population included residents of Borodianka, Ivankiv and Poliske districts ofKyiv region («oblast») and Luhyny, Narodychi and Ovruch districts of Zhytomyr region, 175,100 inhabitants in2017. The study period was 1980-2017. All cancers incidence rates as well as rates of potentially radiation-associated sites (breast, thyroid, hematopoietic and lymphoid systems) were calculated and analysed. Methods of variation statistics, descriptive and analytical epidemiology were used.

RESULTS

The impact of ionizing radiation on population of the most radionuclide-contaminated districts raisesconcerns of the potential threat of adverse cancer effects, especially thyroid cancer. The average total whole-bodyeffective radiation doses received due to cesium during long time (1986-2005) among residents of the study districts (7.6-45.8 mSv) exceeded that in Zhytomyr (5.9 mSv), Kyiv (4.9 mSv) regions and Ukraine as a whole (2.48mSv), but also in other districts in the North Ukraine. The average doses of internal radiation absorbed by the thyroid gland (161-1559 mGy) among the most vulnerable population - children and adolescents (aged 0-18 yearsat the time of the accident) of these areas, and obtained in the short post-accident period, significantly exceedthat in Zhytomyr (87 mGy), Kyiv (81 mGy) regions and Ukraine as a whole (19 mGy). Irradiation rates of adult residents of these territories were lower, but significantly exceeded the average doses received by the population ofUkraine and large administrative units. Overall cancer incidence in the 6 districts during pre- and post-accidentperiods was lower comparing to Ukraine's and Kyiv region's rates, and did not significantly differ from Zhytomyrregion's rates. At the same time, the incidence rates of thyroid cancer significantly exceeded that of the pre-accident period as well as Zhytomyr region's rates.

CONCLUSIONS

The results of the study indicate needs for further monitoring of malignant neoplasms not only inthe population of Ukraine as a whole and its large administrative-territorial units, but also among residents of particular areas, given the likelihood of the realization of the risks of radiation-associated diseases in the distantpost-accident period in accordance with local environmental conditions.

EXPRESSION OF LIPOPROTEIN LIPASE AND c-MYC ONCOGENE IN PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA AFFECTED BY THE CHORNOBYL ACCIDENT

OBJECTIVE

to determine the association between the expression of lipoprotein lipase (LPL) and c-MYC genes inperipheral blood cells of chronic lymphocytic leukemia (CLL) patients affected by the Chornobyl catastrophedepending on the mutational status of IGHV genes.

METHODS

Analysis was performed in the group of 69 CLL patients irradiated due to the Chornobyl NPP accident (58clean-up workers of 1986 year, 6 inhabitants of radionuclide contaminated areas, and 5 evacuees). The IGHV genemutational status was studied by polymerase chain reaction (PCR) followed by direct sequencing. LPL and c-MYCexpression was evaluated by Quantitative Real-time PCR. Data were analyzed with the SPSS software package, version 20.0.

RESULTS

Relative LPL expression levels in CLL samples ranged from 0 to 1663.5 (mean 138.47 ± 30.69, median 26.1).A strong correlation between individual LPL expression levels and IGHV mutational status was found (r = 0.684;p < 0.0001). The average relative c-MYC expression level was 5.7 ± 0.87 (median 2.86; range 0-48.5). No association between c-MYC expression and IGHV mutational status was found. Among unmutated IGHV cases, a correlationbetween LPL and c-MYC gene expression levels was identified: r = 0.351; p = 0.013.

CONCLUSIONS

Our data confirm the dominant concept that unmutated IGHV CLL cases are more sensitive to the actionof proliferative stimuli compared to mutated IGHV CLL cases. This is manifested by an increase in the expression ofa functionally significant LPL gene, is one for the strongest negative prognostic markers in CLL.

THE SPECTRUM OF TP53, SF3B1, AND NOTCH1 MUTATIONS IN CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS EXPOSED TO IONIZING RADIATION DUE TO THE CHORNOBYL NPP ACCIDENT

OBJECTIVE

to analyze TP53, NOTCH1 and SF3B1 mutations in chronic lymphocytic leukemia (CLL) patients, sufferersof Chornobyl NPP accident to clarify the possible relationship between ionizing radiation (IR) and CLL.

METHODS

Mutations of TP53, NOTCH1, and SF3B1 genes were studied by direct sequencing in the main group of 106 CLLpatients exposed to IR due to Chornobyl NPP accident and in the control group of 130 IR non-exposed CLL patients.

RESULTS

We found TP53 and SF3B1 mutations with similar incidence in both groups - 11.3 % and 10.0 % in the maingroup, and 12.7 % and 11.5 % in the control group, respectively. In contrast, the frequency of NOTCH1 mutationswas lower in IR-exposed patients (6.7 % vs 17.7 %; p = 0.012). TP53 mutations were seen with equal frequency amongmutated (11.1 %) and unmutated (11.8 %) immunoglobulin heavy-chain variable gene (IGHV) cases in IR-exposedCLL patients, while the tendency to prevalence of TP53 mutations in unmutated compared with mutated IGHV caseswas found in the control group (14.1 % and 5.6 %, correspondingly; p = 0.178). In IR-exposed group SF3B1 muta-tions were combined with mutations in TP53 almost in half of detected cases. In opposite, in the control group therewas mutual exclusivity between SF3B1 and TP53 lesions (p = 0.001). Among IR-exposed CLL patients we found two dif-ferent cases with identical rare mutation of TP53 gene - c.665C>T substitution (Pro222Leu). This substitution is verylikely to represent inherited TP53 mutation, which may influence CLL development under IR exposure.

CONCLUSION

Our preliminary data suggest that TP53 abnormalities are involved in CLL development in subjectsexposed at the Chornobyl accident and also a possible connection between inherited sensitivity to ionizing radia-tion caused by mutation in TP53, radiation and CLL development.

Distribution of rs2124594 genotypes in chronic lymphocytic leukemia patients depending on radiation anamnesis

OBJECTIVE

to test the method of polymerase chain reaction with following fragments' length restriction to deter mine the rs2124594 polymorphism and to study its contribution in the development of chronic lymphocytic leukemia (CLL) in the post Chornobyl period.

METHODS

Genotypes of rs2124594 were determined in 109 patients with CLL of B cell origin including 53 patients irradiated due to the Chornobyl NPP accident. Genotypes distribution among CLL patients was compared with healthy persons of European origin (the 1000 Genomes Project data set was used as a reference).

RESULTS

Validity of the tested method was confirmed by direct sequencing. Associations between CLL risks and C allele (OR = 2.37; 95 % CI 1.50-3.73; р = 0.003), CLL risks and CT genotype (OR = 2.10; 95 % CI 1.38-3.21; р = 0.0012) were found. Distributions of rs2124594 genotypes in exposed and non exposed to ionizing radiation CLL patients did not differ.

CONCLUSIONS

The association of single nucleotide polymorphisms across the 8q24 chromosome region (positioned at 127180736 and 127183014 near с MYC gene) with CLL risks was confirmed. Modified influence of ionizing radia tion on genetic susceptibility associated with rs2124594 was not found in this pilot study.

Influence of polymorphic variants of the SLC6A4 gene on the frequency of detection of depressive states in the group of the clean up workers of consequences of Chornobyl accident in the remote period after the Chornobyl catastrophe

Mental disorders of the victims are one of the important medical consequences of the Chornobyl accident. It is also known that in the implementation of the pathogenesis of depressive states a significant role belongs to the sero tonin transporter gene (SLC6A4).

OBJECTIVE

To determine the effect of polymorphic variants of the SLC6A4 gene on the frequency of detection of depression in a group of clean up workers in the remote period after the Chornobyl catastrophe.

METHODS

The study was conducted in a group of 59 victims of the Chornobyl NPP accident, divided into two groups (without depression and with depressive symptoms). The diagnosis of depressive disorders was based on a compre hensive assessment of the complaints of the surveyed, the clinical and psychopathological data, the values of the Zung Self Rating Depression Scale (SDS), the Brief Psychiatric Rating Scale (BPRS), the General Health Questionnaire (GHQ 28). DNA from the peripheral blood mononuclear cells was isolated, and the 5 HTTLPR polymorphism was determined by polymerase chain reaction (PCR).

RESULTS

Depressive symptoms were more often found among reconvalescents of acute radiation sickness (ARS) than in the clean up workers without ARS: (p = 0.006). The tendencies of the association of the received dose of exter nal exposure with the number of points on the SDS scale (r = 0.284; p = 0.043), the sum of scores on the BPRS scale (r = 0.686; p = 0.001), depression (r = 0.323, p = 0.017) and its severity (r = 0.273; p = 0.051) were found. Among the examined clean up workers, in comparison with a large group of Europeans without mental disorders, an increase in the number of carriers of the genotype S/S SLC6A4 was found (p = 0.03). Only for the carriers of the S/S genotype, the reciprocal association between the development of depression and the age of the patient was found: r = 0.503 (p = 0.033), between the development of depression and the time from the ChNPP accident: r = 0.581 (p = 0.011), as well as positive correlation of development of depression with dose of irradiation: r = 0.515 (p = 0.025). Among people aged 55 and older, the development of depression was associated with a decrease in the frequency of high ly functional genotype LА/LА to 4.76% versus 31.25% in the absence of depressed symptoms (p = 0.042). In the group of younger patients, the distribution of genotypes did not differ depending on the signs of depression (p = 0.476).

CONCLUSION

The pilot analysis of the distribution of genotypes of the SLC6A4 gene for polymorphisms of 5 HTTLPR and rs25531 in the clean up workers group showed the promise of further studies of the contribution of LА/LА і S/S genotypes to the development of depressive states in combination with the action of the radiation factor.

NOTCH1 mutations in chronic lymphocytic leukemia patients sufferers of Chornobyl NPP accident

Objective - to estimate the frequency of NOTCH1 mutations in chronic lymphocytic leukemia (CLL) patients, suffer ers of Chornobyl NPP accident, for elucidation of their impact in development of radiation associated forms of dis ease.

METHODS

NOTCH1 mutations were determined by polymerase chain reaction followed by direct sequencing in 201 previously untreated patients with CLL of B cell origin: 88 CLL patients, sufferers of the Chornobyl NPP accident, and 113 CLL patients of the control group.

RESULTS

Mutations of NOTCH1 were found in 13.4 % of observed patients, mostly in cases with unmutated heavy chain variable region (IGHV) genes (p = 0.001). Patients of the two groups were comparable by gender, age, stage at diagnosis, and mutational status of IGHV genes. But, the frequency of NOTCH1 mutations in the main group appeared to be lower in comparison with the control group (6.8 % vs 18.6 %; p = 0.015). Furthermore, if in the con trol group the number of NOTCH1 mutations increased in patients requiring first treatment compared with patients at diagnosis (p = 0.012), in the main group such differencies were non significant (p = 0.317). When clinical data of all observed groups of patients were analyzed, the presence of NOTCH1 mutations was associated with more advanced stage of disease, higher initial WBC count, bulky disease, short time to treatment period and progression free survival.

CONCLUSION

Our data confirmed negative prognostic value of NOTCH1 mutations, but suggested to minimal impact of NOCTH1 mutations in CLL development under exposure to ionizing radiation.

Late effects of ionizing radiation on functional status of bronchopulmonary system in COPD patients among the clean-up workers of the Chornobyl NPP accident

The objective of the study was to determine the effects of ionizing radiation on the functional condition of the bronchopulmonary system in clean-up workers of Chornobyl NPP patients with COPD in a remote post-emergency period. Materials and methods. The study of functional characteristics was carried out in 272 patients - 197 clean-up workers of Chornobyl NPP accident (ChNPPA) with radiation exposure from 25 to 988 mSv; 75 - group of nosological control and 20 healthy persons. Results and conclusions. For the clean-up workers of Chornobyl NPP with exposure doses over 500 mSv demonstrated correlation between respiratory function parameters and dose which is confirmed for these patients, compared with irradiated in doses less than 500 mSv and nosology control, a significant decreasing of VC (76,3 ± 8,5%, 82,4 ± 8,5% and 82,7 ± 8,1% accordingly, p <0,05), FVC (78,2 ± 8,3%, 84,3 ± 7,9% і 86,1 ± 9,7%, p <0,05), FEF 50 (26,1 ± 11,5%, 32,6 ± 10,6% і 32,1 ± 12,7%, p <0, 05) і FEF 75 (23,8 ± 8,1%, 27,8 ± 9,3% і 27,6 ± 9,2%, p <0,05). These changers combined with decrease in lung diffusion capacity in cases more than 500 mSv, and indicate severe respiratory disorders in patients with COPD among clean-up workers of ChNPPA.

Analysis of risk factors for chronic obstructive pulmonary disease in clean-up workers of the Chornobyl accident

Objective. To analyze the effects of ionizing exposure, age and smoking on the development of chronic non-specific lung disease in a cohort of liquidators of the Chornobyl consequences included in the Clinical and Epidemiological Registry SI "National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine". Materials and methods. The analysis included data on 7156 of the Chornobyl liquidators, of which 6 257 (87.4 %) men and 899 (12.6 %) women who were examined between 1993 and 2010 by pulmonologist. Results. Chronic bronchopulmonary diseases were detected in 50.0 % of the surveyed persons. The overall exposure dose was significantly higher among liquidators, which developed bronchopulmonary diseases (24.29 ± 0.82 sSv) compared with those without bronchopulmonary disease (14.58 ± 0.62 sSv), p = 0.001. In smokers the incidence of chronic obstructive pulmonary disease was twice higher than in those who did not smoke (10.2 and 5.16 %, respectively, p = 0.0001). Conclusion. The negative effect of ionizing radiation amplified by other risk factors for chronic bronchopulmonary disease: association between exposure doses and somatic pathology manifested in the surveyed people over the age of 45 years; at the same exposure dose risk of bronchopulmonary diseases was higher for smokers.

Analysis of some risk factors for myocardial infarction in a cohort of the Chornobyl clean-up workers (according to the data of Clinical and Epidemiological Registry)

The objective of the paper was to analyze the individual risk factors for coronary heart disease in a group of clean-up workers, who had developed a myocardial infarction (MI) after the Chornobyl NPP accident.

METHODS

Data of 525 clean-up workers with a first MI event were analyzed among all uniquely identifiable clean-up workers registered in the Clinical and Epidemiological Registry (CER) of NRCRM. The comparison was carried out with a control group of 110 residents of Kyiv, who had MI within 2004-2009.

RESULTS

It was found that the proportion of patients who had MI under 45 years was increased in the first 10 years after the Chornobyl accident, being first of all due to the age structure of the clean-up worker's cohort as a whole. The distribution of patients by age in the following years was close to that in the other MI cohorts described in the literature. The external radiation dose of men who developed MI in the first 5 years after the Chornobyl NPP accident was 39.58 ± 6.72 cSv (median 25 cSv) which exceeded the dose of men who had got the MI later (23.78 ± 2.43 cSv, median 12 cSv; p=0.009).

CONCLUSIONS

The quantity of the male patients with minimum number of risk factors was gradually reducing along with time since the Chornobyl accident and accordingly the proportion of patients with three or more risk factors was increased (p=0.001). Incidence of obesity and hypercholesterolemia among male clean-up workers was higher than in the control group of male inhabitants of Kyiv.