Radiation and the Risk of Chronic Lymphocytic and Other Leukemias among Chornobyl Cleanup Workers

Background: Risks of most types of leukemia from exposure to acute high doses of ionizing radiation are well known, but risks associated with protracted exposures, as well as associations between radiation and chronic lymphocytic leukemia (CLL), are not clear.
 Objectives: We estimated relative risks of CLL and non-CLL from protracted exposures to low-dose ionizing radiation.
 Methods: A nested case–control study was conducted in a cohort of 110,645 Ukrainian cleanup workers of the 1986 Chornobyl nuclear power plant accident. Cases of incident leukemia diagnosed in 1986–2006 were confirmed by a panel of expert hematologists/hematopathologists. Controls were matched to cases on place of residence and year of birth. We estimated individual bone marrow radiation doses by the Realistic Analytical Dose Reconstruction with Uncertainty Estimation (RADRUE) method. We then used a conditional logistic regression model to estimate excess relative risk of leukemia per gray (ERR/Gy) of radiation dose.
 Results: We found a significant linear dose response for all leukemia [137 cases, ERR/Gy = 1.26 (95% CI: 0.03, 3.58]. There were nonsignificant positive dose responses for both CLL and non-CLL (ERR/Gy = 0.76 and 1.87, respectively). In our primary analysis excluding 20 cases with direct in-person interviews less than 2 years from start of chemotherapy with an anomalous finding of ERR/Gy = –0.47 (95% CI: less than –0.47, 1.02), the ERR/Gy for the remaining 117 cases was 2.38 (95% CI: 0.49, 5.87). For CLL, the ERR/Gy was 2.58 (95% CI: 0.02, 8.43), and for non-CLL, ERR/Gy was 2.21 (95% CI: 0.05, 7.61). Altogether, 16% of leukemia cases (18% of CLL, 15% of non-CLL) were attributed to radiation exposure.
 Conclusions: Exposure to low doses and to low dose-rates of radiation from post-Chornobyl cleanup work was associated with a significant increase in risk of leukemia, which was statistically consistent with estimates for the Japanese atomic bomb survivors. Based on the primary analysis, we conclude that CLL and non-CLL are both radiosensitive.

Genomic characterization of chronic lymphocytic leukemia (CLL) in radiation-exposed Chornobyl cleanup workers

Background Chronic lymphocytic leukemia (CLL) was the predominant leukemia in a recent study of Chornobyl cleanup workers from Ukraine exposed to radiation (UR-CLL). Radiation risks of CLL significantly increased with increasing bone marrow radiation doses. Current analysis aimed to clarify whether the increased risks were due to radiation or to genetic mutations in the Ukrainian population. Methods A detailed characterization of the genomic landscape was performed in a unique sample of 16 UR-CLL patients and age- and sex-matched unexposed general population Ukrainian-CLL (UN-CLL) and Western-CLL (W-CLL) patients (n = 28 and 100, respectively). Results Mutations in telomere-maintenance pathway genes POT1 and ATM were more frequent in UR-CLL compared to UN-CLL and W-CLL (both p < 0.05). No significant enrichment in copy-number abnormalities at del13q14, del11q, del17p or trisomy12 was identified in UR-CLL compared to other groups. Type of work performed in the Chornobyl zone, age at exposure and at diagnosis, calendar time, and Rai stage were significant predictors of total genetic lesions (all p < 0.05). Tumor telomere length was significantly longer in UR-CLL than in UN-CLL (p = 0.009) and was associated with the POT1 mutation and survival. Conclusions No significant enrichment in copy-number abnormalities at CLL-associated genes was identified in UR-CLL compared to other groups. The novel associations between radiation exposure, telomere maintenance and CLL prognosis identified in this unique case series provide suggestive, though limited data and merit further investigation

System of Psychological Support for Education of Children with Mental Development Delay

Introduction. The paper discusses the issues of psychological support for children with Mental Development Delay (MDD) who represent the majority of school children in the inclusive educational environment. The novelty of the study lies in describing the main types and fields of professional activities of educational psychologists and in constructing an integrated system of the differentiated psychological support for education of this category of children, taking into account variability in their developmental levels at the beginning of formal schooling. Theoretical Basis. This section provides the methodological foundations for the study, including (a) the basic provisions of psychology of children with special needs and correctional pedagogy, based on Vygotsky’s cultural-historical theory; (b) the socio-cultural approach to the analysis of development of educational practice and to the implementation of objectives of psychology of children with special needs at each stage of the development of education for children with disabilities; and (c) the methodology of psychological support for the educational process. The authors (a) described modern approaches to the organization of psychological support for children with MDD and its objectives under modernization of the educational system and (b) analyzed the necessary content and conditions for education of primary school children aimed at meeting their special educational needs. Results and Discussion. The authors consider psychological support for children with MDD as a systematic realization of the main types of an educational psychologist’s professional activity. Types of this activity are differentiated according to the major goals of modern educational practice and contribute to successful learning and development of every child. The main objectives of such support are as follows: (a) identification, and prevention or elimination of the imbalance between kids’ education and development, taking into account their individual abilities; (b) correction of secondary developmental disorders manifested in cognitive, emotional, and socio-behavioral spheres; and (c) creation of conditions for socio-psychological adaptation of the child’s personality. The authors described various types of an educational psychologist’s professional responsibilities, including diagnostic, correctional and developmental, expert and consultative activities. The paper concludes with the provision of criteria for assessing the effectiveness of psychological support

Experimental Research into Conscious Self-Regulation in First-Graders with Developmental Delay

The underdeveloped conscious self-regulation of actions plays a primary role in the disorder-related character of children with developmental delay (DD). This study aimed to analyze and systematize specific occurrences of conscious self-regulation in children&rsquo;s DD-affected cognitive activity. Children aged 7&ndash;8 years were involved in the study (n = 60), including children with DD (n = 40) and school children displaying typical development (n = 20). The dotting test, visual pattern test, and Toulouse&ndash;Pieron attention test are the practical methods used in the study. Mathematical methods of statistics were applied to analyze the study outcome. The experimental research identified and described four levels of conscious self-regulation development in the cognitive activity of children with different learning capacities. The findings proved that children of 7&ndash;8 years with DD have an underdeveloped level of conscious self-regulation of actions in terms of their cognitive activity, and that they differ from their peers regarding typical development in terms of their conscious self-regulation level and skills. Special intervention programs that develop conscious self-regulation in the performance and behavior of children with DD are required to realize their cognitive and personal capacities and provide them with high-quality education

Current Trends in Special Education: Psychological and Pedagogical Support for Students with Learning Disabilities

The article focuses on problems of special education and psychological-pedagogical support for students with learning disabilities. The research aim is to identify current trends in special education for these students, certain conditions and factors that impact their academic performance and development of life competencies. Research methods: analysis of today’s legislation, regulations, proceedings papers, guidance and other policy documents on special educational needs for students with learning disabilities in public elementary and middle school; analysis of statistical data on education for students with learning disabilities in 2019/2020 academic year in all 85 constituent entities of Russian Federation; an online random sample survey among specialists who work in public schools that students with learning disabilities attend. Conclusions based on the conducted study are as follows: the number of students with learning disabilities on inclusive terms is increasing; there is a legal backing and methodological support for special education in public elementary schools; special education conditions need to be provided not only in public elementary school but also in middle school; inclusive education specialists are lacking knowledge on learning, teaching and psychological-pedagogical support for students with learning disabilities in today’s school environment; there is a shortage of special education professionals in schools and learning centres. The results of the study can be used to develop educational policy, learning plans, programmes and to improve quality of inclusive education specialists training

Clinical characteristics of chronic lymphocytic leukemia occurring in chornobyl cleanup workers.

The recently demonstrated radiation-induction of chronic lymphocytic leukemia (CLL) raises the question as to whether the amount of radiation exposure influences any of the clinical characteristics of the disease. We evaluated the relationship between bone marrow radiation doses and clinical characteristics and survival of 79 CLL cases diagnosed during 1986-2006 in a cohort of 110 645 male workers who participated in the cleanup work of the Chornobyl nuclear accident in Ukraine in 1986. All diagnoses were confirmed by an independent International Hematology Panel. Patients were followed up to the date of death or end of follow-up on 31 October 2010. The median age at diagnosis was 57 years. Median bone marrow dose was 22.6 milligray (mGy) and was not associated with time between exposure and clinical diagnosis of CLL (latent period), age, peripheral blood lymphocyte count or clinical stage of disease in univariate and multivariate analyses. Latent period was significantly shorter among those older at first exposure, smokers and those with higher frequency of visits to the doctor prior to diagnosis. A significant increase in the risk of death with increasing radiation dose was observed (p = 0.03, hazard ratio = 2.38, 95% confidence interval: 1.11,5.08 comparing those with doses ≥22 mGy to doses &lt;22 mGy). After adjustment for radiation dose, survival of CLL cases was significantly shorter among those with younger age at first exposure, higher peripheral blood lymphocyte count, more advanced clinical stage of disease and older age at diagnosis (all p &lt; 0.05). This is the first study to examine association between bone marrow radiation doses from the Chornobyl accident and clinical manifestations of the CLL in Chornobyl cleanup workers. The current study provides new evidence on the association of radiation dose and younger age at first radiation exposure at Chornobyl with shorter survival after diagnosis. Future studies are necessary with more cases in order to improve the statistical power of these analyses and to determine their significance. Copyright © 2016 John Wiley &amp; Sons, Ltd

Clinical characteristics of chronic lymphocytic leukemia occurring in chornobyl cleanup workers.

The recently demonstrated radiation-induction of chronic lymphocytic leukemia (CLL) raises the question as to whether the amount of radiation exposure influences any of the clinical characteristics of the disease. We evaluated the relationship between bone marrow radiation doses and clinical characteristics and survival of 79 CLL cases diagnosed during 1986-2006 in a cohort of 110 645 male workers who participated in the cleanup work of the Chornobyl nuclear accident in Ukraine in 1986. All diagnoses were confirmed by an independent International Hematology Panel. Patients were followed up to the date of death or end of follow-up on 31 October 2010. The median age at diagnosis was 57 years. Median bone marrow dose was 22.6 milligray (mGy) and was not associated with time between exposure and clinical diagnosis of CLL (latent period), age, peripheral blood lymphocyte count or clinical stage of disease in univariate and multivariate analyses. Latent period was significantly shorter among those older at first exposure, smokers and those with higher frequency of visits to the doctor prior to diagnosis. A significant increase in the risk of death with increasing radiation dose was observed (p = 0.03, hazard ratio = 2.38, 95% confidence interval: 1.11,5.08 comparing those with doses ≥22 mGy to doses &lt;22 mGy). After adjustment for radiation dose, survival of CLL cases was significantly shorter among those with younger age at first exposure, higher peripheral blood lymphocyte count, more advanced clinical stage of disease and older age at diagnosis (all p &lt; 0.05). This is the first study to examine association between bone marrow radiation doses from the Chornobyl accident and clinical manifestations of the CLL in Chornobyl cleanup workers. The current study provides new evidence on the association of radiation dose and younger age at first radiation exposure at Chornobyl with shorter survival after diagnosis. Future studies are necessary with more cases in order to improve the statistical power of these analyses and to determine their significance. Copyright © 2016 John Wiley &amp; Sons, Ltd

Radiation and the risk of chronic lymphocytic and other leukemias among chornobyl cleanup workers.

BACKGROUND: Risks of most types of leukemia from exposure to acute high doses of ionizing radiation are well known, but risks associated with protracted exposures, as well as associations between radiation and chronic lymphocytic leukemia (CLL), are not clear. OBJECTIVES: We estimated relative risks of CLL and non-CLL from protracted exposures to low-dose ionizing radiation. METHODS: A nested case-control study was conducted in a cohort of 110,645 Ukrainian cleanup workers of the 1986 Chornobyl nuclear power plant accident. Cases of incident leukemia diagnosed in 1986-2006 were confirmed by a panel of expert hematologists/hematopathologists. Controls were matched to cases on place of residence and year of birth. We estimated individual bone marrow radiation doses by the Realistic Analytical Dose Reconstruction with Uncertainty Estimation (RADRUE) method. We then used a conditional logistic regression model to estimate excess relative risk of leukemia per gray (ERR/Gy) of radiation dose. RESULTS: We found a significant linear dose response for all leukemia [137 cases, ERR/Gy = 1.26 (95% CI: 0.03, 3.58]. There were nonsignificant positive dose responses for both CLL and non-CLL (ERR/Gy = 0.76 and 1.87, respectively). In our primary analysis excluding 20 cases with direct in-person interviews &lt; 2 years from start of chemotherapy with an anomalous finding of ERR/Gy = -0.47 (95% CI: &lt; -0.47, 1.02), the ERR/Gy for the remaining 117 cases was 2.38 (95% CI: 0.49, 5.87). For CLL, the ERR/Gy was 2.58 (95% CI: 0.02, 8.43), and for non-CLL, ERR/Gy was 2.21 (95% CI: 0.05, 7.61). Altogether, 16% of leukemia cases (18% of CLL, 15% of non-CLL) were attributed to radiation exposure. CONCLUSIONS: Exposure to low doses and to low dose-rates of radiation from post-Chornobyl cleanup work was associated with a significant increase in risk of leukemia, which was statistically consistent with estimates for the Japanese atomic bomb survivors. Based on the primary analysis, we conclude that CLL and non-CLL are both radiosensitive