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The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are considered excellent candidates for the separation of radionuclides under complex conditions due to their high specific surface areas, tunable pore structures and controllable functionalities. In this review, we summarized the design, preparation and functionalization of porous materials and their application for separation of radionuclides in the past five years, discussed the separation performance and analyzed the structure-activity relationship between various radionuclides and porous materials, and systematically clarified their characterization and mechanism of different type porous materials. We also introduced the detection, irradiation and chemical toxicity of different reflective radionuclides. [ABSTRACT FROM AUTHOR]

This research has been conducted to study the activity of apoptosis of peripheral blood lymphocytes (PBLs) and the frequency of CD3-/CD4+ PBLs in people who have suffered chronic low-intensity radiation exposure. An increase in the frequency of apoptotic cells (TUNEL) is demonstrated in the group of exposed individuals relative to the control group. The frequency of mutations in the gene of the T-cell receptor in the exposed individuals is also elevated. Analyses of the mean values of apoptosis and CD3-CD4+ PBLs in different dose subgroups have found an increase in the proportion of cells with mutant T-cell receptors against the background of a decrease in the frequency of apoptotic cells in the range of low and medium radiation doses.

A new model of the hematopoietic system response in humans chronically exposed to ionizing radiation describes the dynamics of the hematopoietic stem cell compartment as well as the dynamics of each of the four blood cell types (lymphocytes, neutrophiles, erythrocytes, and platelets). The required model parameters were estimated based on available results of human and experimental animal studies. They include the steady-state number of hematopoietic stem cells and peripheral blood cell lines in an unexposed organism, amplification parameters for each blood line, parameters describing proliferation and apoptosis, parameters of feedback functions regulating the steady-state numbers, and characteristics of radiosensitivity related to cell death and non-lethal cell damage. The model predictions were tested using data on hematological measurements (e.g., blood counts) performed in 1950-1956 in the Techa River residents chronically exposed to ionizing radiation since 1949. The suggested model of hematopoiesis is capable of describing experimental findings in the Techa River Cohort, including: (1) slopes of the dose-effect curves reflecting the inhibition of hematopoiesis due to chronic ionizing radiation, (2) delay in effect of chronic exposure and accumulated character of the effect, and (3) dose-rate patterns for different cytopenic states (e.g., leukopenia, thrombocytopenia).

A new model of the hematopoietic system for humans chronically exposed to ionizing radiation allows for quantitative description of the initial hematopoiesis inhibition and subsequent increase in the risks of late stochastic effects such as leukemia. This model describes the dynamics of the hematopoietic stem cell compartment as well as the dynamics of each of the three blood cell types (leukocytes, erythrocytes, and platelets). The model parameters are estimated from the results of other experiments. They include the steady-state numbers of hematopoietic stem cells and peripheral blood cell lines for an unexposed organism, amplification parameters for each blood cell line, parameters describing the proliferation and apoptosis, parameters of feedback functions regulating the steady-state numbers, and characteristics of radiosensitivity in respect to cell death and non-lethal cell damages. The dynamic model of hematopoiesis is applied to the data on a subcohort of the Techa River residents with hematological measurements (e.g., blood counts) performed in 1950-1956 (which totals to about 3,500 exposed individuals). Among well-described effects observed in these data are the slope values of the dose-effect curves describing the hematopoietic inhibition and the dose rate patterns of the fractions of cytopenic states (e.g., leukopenia, thrombocytopenia). The model has been further generalized by inclusion of the component describing the risk of late stochastic effects. The risks of the development of late effects (such as leukemia) in population groups with specific patterns of early reactions in hematopoiesis (such as leukopenia induced by ionizing radiation) are investigated using simulation studies and compared to data.

The major goal of this study is to investigate and quantitatively describe the nature of the relationship between the characteristics of chronic exposure to ionizing radiation and specific patterns of hematopoiesis reduction. The study is based on about 3,200 hemograms taken for inhabitants of the Techa riverside villages over the years 1951-1956, i.e., the period characterized by a gradual decrease in dose rates. The mean cumulative red bone marrow dose was 333.6 + or - 4.6 mGy. The approach to statistical analyses involved both empirical methods and modeling (generalized linear models and logistic regressions). The results of the analyses highlighted a gradual increase in the frequency of cytopenias with dose rate. The impact of exposure on hematopoiesis reduction patterns was found to be more substantial than that of age and health status. Dose rates resulting in a two-fold increase in the frequency of cytopenias have been estimated.

The major goal of this study was to identify and quantitatively describe the association between the characteristics of chronic (low-dose rate) exposure to (low LET) ionizing radiation and cellularity of peripheral blood cell lines. About 3,200 hemograms (i.e., spectra of blood counts) obtained over the years of maximal exposure to ionizing radiation (1950-1956) for inhabitants of the Techa River were used in analyses. The mean cumulative red bone marrow dose (with standard errors), calculated using Techa River Dosimetry System-2000, was 333.6 +/- 4.6 mGy (SD = 259.9 mGy, max = 1151 mGy) to the year 1956. The statistical approach included both empirical methods for estimating frequencies of cytopenic states of the investigated blood cell lines (e.g. neutrophile, platelets, erythrocyte, etc.), and regression methods, including generalized linear models and logistic regressions which allowed taking into account confounding factors (e.g., attained age, age at maximal exposure, presence of concomitant diseases, and demographic characteristics). The results of the analyses demonstrated hematopoiesis inhibition manifested by a decrease in peripheral blood cellularity and an increase in the frequency of cytopenia in all blood cell lines (leukocytes, including lymphocytes, monocytes, neutrophiles, as well as platelets and erythrocytes). The intensity of hematopoiesis inhibition in the period of maximal exposures is determined by the combined influence of the dose rate and cumulative dose. The contribution of specific confounding factors was quantified and shown to be much less important than dose characteristics. The best predictor among dose characteristics was identified for each blood cell line. A 2-fold increase in dose rate is assumed to be a characteristic of radiosensitivity and a quantitative characteristic of the effect.

This article discusses the most important information on health effects in the Urals region (Russia) of residents exposed to radiation from activities of a weapon plutonium separation plant. The population residing on the contaminated territory was exposed to chronic combined irradiation (external gamma-irradiation and internal irradiation due to Sr-90 and Cs-137). The red bone marrow (RBM) was the critical organ affected as a result of radiation events in the Urals. In the early period, after the discharges of radioactive wastes into the river Techa (about 3 M Ci) started, cases of chronic radiation sickness (CRS; 940 cases, in total), postirradiation reactions manifested by changes in blood parameters (e.g., leukopenia, thrombocytopenia, granulocytopenia), nervous system disorders, immunity changes and ostealgic syndrome were registered in a portion of those riverside village residents who had received the highest doses. Increased leukemia and cancer mortality and morbidity rates were noted among this population in later periods. No late effects were observed in residents exposed to an explosion in a radioactive waste depot in September, 1957 when radioactive wastes with about 20 M Ci of activity were released into the environment. Similarly, the offspring of the residents exposed on the Techa also did not display any late effects. The data about the possibilities of long-term (43-45 years after the start of exposure) biological indication of chronic internal exposure are presented. The methods used in the study include in situ fluorescent hybridization, analysis of mutations in the TCR gene of peripheral blood lymphocytes and erythrocyte mutations in the glycophorine A system. No dependence of genomic translocations and mutations in glycophorine A on cumulative exposure dose to RBM was traced.

Blood cells are used as the most sensitive marker to determine the effects and intensity of ionizing radiation. This descriptive study aimed to evaluate the effect of radiation exposure on hematological parameters in healthcare workers who were exposed to radiation in a university hospital between May and June 2021. A total of 339 participants were included, of which 169 (49.9%) were radiation workers and 170 (50.1%) were in the control group. A decrease was observed in white blood cell and neutrophil counts in those exposed to ionizing radiation for less than 10 years; however, white blood cell, neutrophil, hemoglobin levels decreased, and red cell distribution width (RDW) levels increased in those exposed to ionizing radiation for 10 years or more (p < 0.005). A statistically significant increase was observed in the RDW and lymphocyte levels as the years of work experience in the profession increase in the group exposed to IR. The findings indicate that the effect of low-dose ionizing radiation on the hematopoietic system is related to the frequency and duration of the dose. Hematological parameters can be sensitive biomarkers of low-dose ionizing radiation; possible disturbances in the hematopoietic system can be recognized before the onset of symptoms, and necessary precautions can be taken promptly. [ABSTRACT FROM AUTHOR]

Internal contamination by radionuclides may constitute a major source of exposure and biological damage after radiation accidents and potentially in a dirty bomb or improvised nuclear device scenario. We injected male C57BL/6 mice with radiolabeled cesium chloride solution (137CsCl) to evaluate the biological effects of varying cumulative doses and dose rates in a two-week study. Injection activities of 137CsCl were 5.71, 6.78, 7.67 and 9.29 MBq, calculated to achieve a target dose of 4 Gy at days 14, 7, 5 and 3, respectively. We collected whole blood samples at days 2, 3, 5, 7 and 14 so that we can publish the issue in Decemberfrom all injection groups and measured gene expression using Agilent Mouse Whole Genome microarrays. We identified both dose-rate-independent and dose-rate-dependent gene expression responses in the time series. Gene Ontology analysis indicated a rapid and persistent immune response to the chronic low-dose-rate irradiation, consistent with depletion of radiosensitive B cells. Pathways impacting platelet aggregation and TP53 signaling appeared activated, but not consistently at all times in the study. Clustering of genes by pattern and identification of dose-rate-independent and -dependent genes provided insight into possible drivers of the dynamic transcriptome response in vivo, and also indicated that TP53 signaling may be upstream of very different transcript response patterns. This characterization of the biological response of blood cells to internal radiation at varying doses and dose rates is an important step in understanding the effects of internal contamination after a nuclear event. [ABSTRACT FROM AUTHOR]

Background: Numerous studies have concentrated on high-dose radiation exposed accidentally or through therapy, and few involve low-dose occupational exposure, to investigate the correlation between low-dose ionizing radiation and changing hematological parameters among medical workers. Methods: Using a prospective cohort study design, we collected health examination reports and personal dose monitoring data from medical workers and used Poisson regression and restricted cubic spline models to assess the correlation between changing hematological parameters and cumulative radiation dose and determine the dose-response relationship. Results: We observed that changing platelet of 1265 medical workers followed up was statistically different among the cumulative dose groups (P = 0.010). Although the linear trend tested was not statistically significant (Ptrend = 0.258), the non-linear trend tested was statistically significant (Pnon-linear = 0.007). Overall, there was a correlation between changing platelets and cumulative radiation dose (a change of βa 0.008 × 109/L during biennially after adjusting for gender, age at baseline, service at baseline, occupation, medical level, and smoking habits; 95% confidence interval [CI] = 0.003,0.014 × 109/L). Moreover, we also found positive first and then negative dose-response relationships between cumulative radiation dose and changing platelets by restricted cubic spline models, while there were negative patterns of the baseline service not less than 10 years (− 0.015 × 109/L, 95% CI = − 0.024, − 0.007 × 109/L) and radiation nurses(− 0.033 × 109/L, 95% CI = − 0.049, − 0.016 × 109/L). Conclusion: We concluded that although the exposure dose was below the limit, medical workers exposed to low-dose ionizing radiation for a short period of time might have increased first and then decreased platelets, and there was a dose-response relationship between the cumulative radiation dose and platelets changing. [ABSTRACT FROM AUTHOR]

Purpose: Among other reasons, the deteriorating global security situation and dangers associated with nuclear weapons have increased the need for deeper knowledge of the basic mechanisms involving the human immune system and ionizing radiation (IR). We conducted a review as to the effects of IR on thymic tissue, and particularly on the development of thymocytes and the T lymphocytes population in peripheral blood. Existing knowledge on this topic is based in part on national registers that store records concerning irradiated people. The majority of studies in this area, however, are based on experimental animal models. The main open question in this subject area regards the delayed effects of IR on thymus tissue, development of thymocytes, and subsequent impact on the immune system. Findings acquired to date on effects of IR are contributing to emerging fields such as immunotherapy, the objective of which is to support or activate natural immunity response. Methods: Recent research articles were reviewed regarding the influence of IR on thymus tissue and thymocytes development. Results: Differentiation and proliferation of thymocytes constitute a complex and sensitive process that is partially altered after irradiation, as are, too, the mechanisms for movement of early (derived from bone marrow) and derived (thymus derivatives) precursors. Disruption of these processes may lead to alteration of immune system function. Conclusions: Low doses (<200 mGy) may lead to changes in or disruption of functions of the thymus, thymocytes, and mechanisms of the immune system. The extent of IR's influence is dependent not only on the individual's radiosensitivity but also on his or her sex and age. With increasing absorbed IR dose, the risk of damage to thymus tissue and thymocytes in the organism rises and the extent of damage increases. [ABSTRACT FROM AUTHOR]

Dose- and dose rate-dependent increase in the number of СD3+СD16+CD56+-lymphocytes and lysosomal activity of neutrophils was noted in peripheral blood of the Techa riverside residents with increased level of TCR gene-mutated T lymphocytes long after chronic exposure of predominantly red bone marrow (mean exposure dose was 0.89 ± 0.09 Gy, individual dose range was 0.09-1.96 Gy). The performed analysis showed that the above-mentioned immunological changes could be a response to an increase in the frequency of mutations (TCR mutations in particular) in the cells of exposed individuals. [ABSTRACT FROM AUTHOR]

The hematological effects of chronic radiation exposure in males of the pygmy wood mouse (Apodemus uralensis Pall., 1811) from the East Urals radioactive trace (EURT) area were assessed, taking into account population abundance and reproductive status (immature, ripening, and mature yearlings). For this purpose, we analyzed the morpho-functional characteristics of erythrocytes (red cell indices [MCV, MCH, MCHC], red cell count, activity of antioxidant enzymes [GSH-Px, CAT], lipid peroxidation, glycolysis, osmotic resistance, methaemoglobin content) and blood plasma components (free hemoglobin, total lipids, total cholesterol, and glucose) in the background territory and the EURT area; these areas have a density of soil contamination with 90Sr of 12,851 and 198 kBq × m−2, respectively (four and two order of magnitude higher than the background value). The data indicate the “hyperfunctional” state of the erythrocyte, aimed at activation of the gas transport function of blood in the radioactive environment. This, as a consequence, determines the insufficiency of energy supply of the cell defense system necessary to maintain the structural integrity of the membrane. Intensification of membrane lipid peroxidation, reduction of osmotic resistance and GSH-Px activity in red cells, an increase in the degree of intravascular hemolysis, and tendency towards erythropenia indicate the processes of accelerated aging of erythrocytes and their more pronounced destruction in the circulatory bed. The level of the hematological response increased with increasing radiation burden and was more pronounced with a large population size. The interaction effect of “overpopulation” and “radioactive pollution” was observed to a lesser degree for ripening males, and was very small for sexually mature animals. Immature males from the EURT head part with internal whole-body radiation doses of 0.0045-0.35 mGy/day can be considered as the most sensitive group to the factors synergy, including radiation damage and overabundance population. [ABSTRACT FROM AUTHOR]

Purpose: The present study aimed to evaluate the protective role of "Morus alba Linn (Family: Moraceae) commonly known as mulberry" leaves extract against hazardous effects of gamma rays in male rats. Materials and methods: Thirty six male albino rats were divided into six groups (six rats/group); (1) control group received 1ml distilled water, (2) low dose of extract (100 mg/kg) group treated daily with low oral dose of ethanolic extract of mulberry leaves (100 mg/kg body weight (b.wt.)) for 21 consecutive days, (3) high dose of extract (200mg/kg) group treated daily with high oral dose of ethanolic extract of mulberry leaves (200mg/kg b.wt.) for the same period, (4) irradiated group rats were subjected to whole body gamma irradiation at a shot dose of 7 Gy, (5) low dose of extractþirradiated group treated daily with low oral dose of ethanolic extract of mulberry leaves (100 mg/kg b.wt.) for 21 consecutive days then rats were exposed to gamma irradiation at a single dose of 7 Gy, (6) high dose of extractþirradiation group treated daily with high oral dose of ethanolic extract of mulberry leaves (200mg/kg b.wt.) for 21 consecutive days then rats were exposed to gamma irradiation at a single dose of 7 Gy. Rats were sacrificed 1, 7, 15 days post gamma irradiation in all groups. Blood samples were taken at three intervals time in the six groups. Results: The results showed that whole body irradiation of rats induced significant decrease (p<0.05) in red blood cells (RBCs), hemoglobin (Hb), hematocrit percentage (HCT%), platelet, white blood cells (WBCs), lymphocytes, neutrophils, serum glucose-6-phosphate dehydrogenase (G-6-PD) and insulin. The data also showed significant increase (p<0.05) in serum total lipids, phospholipids, cholesterol, triglycerides, lactate dehydrogenase (LDH), creatine kinase (CK), and plasma glucose. Administration of mulberry leaves extract, either low or high concentrations to rats prior to irradiation caused significant improvement in the studied parameters. Conclusions: Mulberry leaves extract prior to exposure to gamma irradiation has radio protector against hazardous effect of irradiation in male rats. [ABSTRACT FROM AUTHOR]

Background: The radioactive isotope Strontium-90 (90Sr) may be released as a component of fallout from nuclear accidents, or in the event of a radiological incident such as detonation of an improvised nuclear device, and if ingested poses a significant health risk to exposed individuals. In order to better understand the response to 90Sr, using an easily attainable and standard biodosimetry sample fluid, we analyzed the global transcriptomic response of blood cells in an in vivo model system. Results: We injected C57BL/6 mice with a solution of 90SrCl2 and followed them over a 30-day period. At days 4, 7, 9, 25 and 30, we collected blood and isolated RNA for microarray analyses. These days corresponded to target doses in a range from 1-5 Gy. We investigated changes in mRNA levels using microarrays, and changes in specific microRNA (miRNA) predicted to be involved in the response using qRT-PCR. We identified 8082 differentially expressed genes in the blood of mice exposed to 90Sr compared with controls. Common biological functions were affected throughout the study, including apoptosis of B and T lymphocytes, and atrophy of lymphoid organs. Cellular functions such as RNA degradation and lipid metabolism were also affected during the study. The broad down regulation of genes observed in our study suggested a potential role for miRNA in gene regulation. We tested candidate miRNAs, mmu-miR-16, mmu-miR-124, mmu-miR-125 and mmu-mir-21; and found that all were induced at the earliest time point, day 4. Conclusions: Our study is the first to report the transcriptomic response of blood cells to the internal emitter 90Sr in mouse and a possible role for microRNA in gene regulation after 90Sr exposure. The most dramatic effect was observed on gene expression related to B-cell development and RNA maintenance. These functions were affected by genes that were down regulated throughout the study, suggesting severely compromised antigen response, which may be a result of the deposition of the radioisotope proximal to the hematopoietic compartment in bone. [ABSTRACT FROM AUTHOR]

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A biologically motivated dynamical model of the lymphocytopoietic system in irradiated humans is applied here to analyze the data obtained under hematological examinations of residents of Techa riverside villages. Those people were exposed to chronic irradiation with varying dose rates, due to the radioactive contamination of the river basin by the Mayak Production Association. Modeling studies revealed the relationship between the dynamics of the lymphocytopoietic system in the examined individuals and the variation of dose rate over the considered period of time. It is found that the developed model is capable of reproducing the decreased level of blood lymphocyte concentration observed during the period of maximum radiation exposure, the recovery processes in the system observed during the period of decreasing dose rate, as well as the enhanced mitotic activity of bone marrow precursor cells in this hematopoietic lineage observed during the entire period under consideration. Mechanisms of these effects of chronic irradiation on the human lymphocytopoietic system are elucidated based on the applied model. The results obtained demonstrate the efficiency of the developed model in the analysis, investigation, and prediction of effects of chronic irradiation with varying dose rate on the human lymphocytopoietic system. In particular, the developed model can be used for predicting any radiation injury of this vital system in people exposed to chronic irradiation due to environmental radiological events, such as anthropogenic radiation accidents or radiological terroristic attacks. [ABSTRACT FROM AUTHOR]

Background:Little is known about leukaemia risk following chronic radiation exposures at low dose rates. The Techa River Cohort of individuals residing in riverside villages between 1950 and 1961 when releases from the Mayak plutonium production complex contaminated the river allows quantification of leukaemia risks associated with chronic low-dose-rate internal and external exposures.Methods:Excess relative risk models described the dose-response relationship between radiation dose on the basis of updated dose estimates and the incidence of haematological malignancies ascertained between 1953 and 2007 among 28 223 cohort members, adjusted for attained age, sex, and other factors.Results:Almost half of the 72 leukaemia cases (excluding chronic lymphocytic leukaemia (CLL)) were estimated to be associated with radiation exposure. These data are consistent with a linear dose response with no evidence of modification. The excess relative risk estimate was 0.22 per 100 mGy. There was no evidence of significant dose effect for CLL or other haematopoietic malignancies.Conclusion:These analyses demonstrate that radiation exposures, similar to those received by populations exposed as a consequence of nuclear accidents, are associated with long-term dose-related increases in leukaemia risks. Using updated dose estimates, the leukaemia risk per unit dose is about half of that based on previous dosimetry. [ABSTRACT FROM AUTHOR]

Background: After the Chernobyl nuclear accident on April 26, 1986, all children in the contaminated territory of the Narodichesky region, Zhitomir Oblast, Ukraine, were obliged to participate in a yearly medical examination. We present the results from these examinations for the years 1993 to 1998. Since the hematopoietic system is an important target, we investigated the association between residential soil density of 137Caesium (137Cs) and hemoglobin concentration, and erythrocyte, platelet, and leukocyte counts in 1,251 children, using 4,989 repeated measurements taken from 1993 to 1998.Methods: Soil contamination measurements from 38 settlements were used as exposures. Blood counts were conducted using the same auto-analyzer in all investigations for all years. We used linear mixed models to compensate for the repeated measurements of each child over the six year period. We estimated the adjusted means for all markers, controlling for potential confounders.Results: Data show a statistically significant reduction in red and white blood cell counts, platelet counts and hemoglobin with increasing residential 137Cs soil contamination. Over the six-year observation period, hematologic markers did improve. In children with the higher exposure who were born before the accident, this improvement was more pronounced for platelet counts, and less for red blood cells and hemoglobin. There was no exposurextime interaction for white blood cell counts and not in 702 children who were born after the accident. The initial exposure gradient persisted in this sub-sample of children.Conclusion: The study is the first longitudinal analysis from a large cohort of children after the Chernobyl accident. The findings suggest persistent adverse hematological effects associated with residential 137Cs exposure. [ABSTRACT FROM AUTHOR]