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Aim To investigate the protective effect of dimethyl fumarate on spleen injury induced by gamma radiation in mice and the related mechanism. Methods C57BL/6 mice were randomly divided into the blank control group, radiation model group and DMF administration group, which were administered once at 12 h before irradiation and once at 0. 5 h, 12 h, 24 h and 48 h after irradiation. The 30-day survival rate, body weight and pathological injury of spleen were measured after a one-time total body irradiation of Co 7 rays (8 Gy). TUNEL staining was used to detect apoptosis of spleen cells. Enzyme-linked immunoassay ( ELISA) was applied to detect the contents of TNF-a, IL-1 p, IL-6, IL-18, NLRP3 and AIM2 in spleen. Western blot test and immunofluorescence staining test was employed to verify the changes of NLRP3 and AIM2 contents in spleen tissue after irradiation. Results DMF could obviously improve the survival rate of irradiated mice, improve the weight loss of irradiated mice, re-duce the pathological injury of spleen, and inhibit the apoptosis of spleen cells after irradiation. ELISA results showed that DMF could significantly inhibit the increase of spleen inflammatory cytokines TNF-a, IL-lp, IL-6, IL-18 and inflammasome components NL-RP3 and AIM2 induced by irradiation. Western blot and tissue immunofluorescence staining also confirmed that DMF could inhibit the increase of NLRP3 and AIM2 inflammasome protein levels caused by irradiation. Meanwhile, NLRP3 agonist and AIM2 agonist could antagonize the radiation protection effect of DMF on spleen cells. Conclusion DMF can ameliorate spleen injury of Co 7-ray injured mice, and its mechanism is closely related to NLRP3/AIM2 inflamma-somes, which can be used as a potential protective drug for radiation injury.
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Objective To examine the effects of ionizing radiation on blood pressure and electrocardiography among healthcare workers in department of cardiovascular diseases, and to provide a reference for formulating the protective interventions against radiation exposure. Methods A total of 127 healthcare workers with radiation exposure in the Department of Cardiovascular Diseases of The 904th Hospital of the Joint Logistics Support Force of the PLA from 2018 to 2022 were included in the observation group. Meanwhile, 127 age- and gender-matched healthcare workers without radiation exposure in the same department during the same study period were included in the control group. The systolic blood pressure, diastolic blood pressure, heart rate, and the detection rates of hypertension and abnormal electrocardiography were compared between groups. Results There were no significant differences between groups in mean age (t = 0.77, P > 0.05), sex (χ2 = 0.02, P > 0.05), prevalence of smoking (χ2 = 0.28, P > 0.05), and alcohol consumption (χ2 = 0.02, P > 0.05). There were significant differences between the observation and control groups in systolic blood pressure [(127.77 ± 15.43) mmHg vs. (111.23 ± 19.10) mmHg; t = 4.21, P < 0.05], diastolic blood pressure [(79.32 ± 8.23) mmHg vs. (69.91 ± 10.21) mmHg; t = 4.09, P < 0.05], prevalence of hypertension [17.32% (22/127) vs. 8.66% (11/127); χ2 = 4.21, P < 0.05], heart rate [(81.10 ± 11.27) beats/min vs. (70.45 ± 10.55) beats/min; t = 4.33, P < 0.05], and abnormal rate of electrocardiography [21.26% (27/127) vs. 10.24% (13/127); χ2 = 5.82, P < 0.05]. Conclusion Ionizing radiation affects blood pressure and electrocardiography among healthcare workers in department of cardiovascular diseases. The prevention and monitoring of radiation exposure and occupational physical examination should be improved among healthcare workers with exposure to radiation in the department of cardiovascular diseases, with aims to reduce the hazard of radiation exposure and protect the health of healthcare workers.
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Objective To investigate the mechanism of fractionated low-dose ionizing radiation (LDIR) in the induction of EA.hy926 cell senescence. Methods EA.hy926 cells were irradiated with X-ray at 0, 50, 100, and 200 mGy × 4, respectively, and cultured for 24, 48, and 72 h. Several indicators were measured, including the levels of cellular senescence-associated β-galactosidase (SA-β-gal) staining, mRNA levels of senescence-associated cell cycle protein-dependent kinase inhibitor genes CDKN1A and CDKN2A, reactive oxygen species (ROS), total antioxidant capacity (T-AOC), and phosphorylated H2A histone family member X (γ-H2AX). Results After 4 fractionated LDIR, compared with the control group, the treatment groups showed increased nucleus area, blurred cell edge, and increased SA-β-gal positive area (P < 0.05) at 24, 48 and 72 h. After 4 fractionated LDIR, the mRNA level of CDKN1A increased in the 100 and 200 mGy × 4 groups at 24 and 48 h (P < 0.05), and CDKN2A mRNA level increased in the 100 and 200 mGy × 4 groups at 48 and 72 h (P < 0.05). The fluorescence intensity of ROS increased in treatment groups at 24, 48, and 72 h after 4 fractionated LDIR (P < 0.05). After 4 fractionated LDIR, the T-AOC level increased in the 100 and 200 mGy × 4 groups at 24 h (P < 0.05), and T-AOC level increased in all treatment groups at 48 and 72 h (P < 0.05). After 4 fractionated LDIR, γ-H2AX fluorescence intensity increased in all treatment groups at 24 h (P < 0.05), and the fluorescence intensity increased in the 100 and 200 mGy × 4 groups at 48 and 72 h (P < 0.05). Conclusion Fractionated LDIR can induce cellular senescence in EA.hy926 cells by impacting the cellular oxidation-antioxidation and oxidative damage levels, and the effects were relatively evident at 100 and 200 mGy.
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ABSTRACT Objective: To compare cancer mortality among workers exposed to gamma and X radiation and the general population of the city of São Paulo, as well as that of the subgroup monitored with those not monitored for gamma and X radiation in a work unit with ionizing radiation based in the city of São Paulo. Methods: Between 2016 and 2021, a retrospective open cohort study was carried out with workers who were employed from 08/31/1956 to 12/31/2016 based on data collected at the company and in official institutions. Standardized mortality ratios (SMR) were calculated by sex, age and calendar period of cancers grouped according to type, risk factor and organ system in two analyses: in the external analysis, the mortality of the study population was compared with that of the general population of the city of São Paulo; In the internal analysis, the mortality of the monitored subgroup was compared with that of the subgroup not monitored for gamma and X radiation. Results: The external mortality analysis showed SMR=0.224 (95%CI 0.208-0.240) and the healthy worker effect, while the internal mortality analysis showed SMR=0.685 (95%CI 0.618-0.758). Conclusion: This study showed lower cancer mortality among exposed workers when compared to mortality in the general population and the healthy worker effect. Among workers monitored for gamma and X radiation, cancer mortality was lower when compared to those not monitored.
RESUMO Objetivo: Comparar a mortalidade por câncer entre trabalhadores expostos à radiação gama e X e a população geral do município de São Paulo, bem como a do subgrupo monitorado com o não monitorado para radiação gama e X em uma unidade de trabalho sediada no município de São Paulo. Métodos: Entre 2016 e 2021 foi realizado estudo de coorte aberta retrospectiva com trabalhadores que tiveram vínculo empregatício desde 31/08/1956 até 31/12/2016 a partir de dados coletados na empresa e em instituições oficiais. Foram calculadas as razões de mortalidade padronizadas (RMP) por sexo, idade e período calendário de cânceres agrupados segundo o tipo, o fator de risco e o sistema orgânico em duas análises: na análise externa, comparou-se a mortalidade da população de estudo com a da população geral do município de São Paulo; já na análise interna, comparou-se a mortalidade do subgrupo monitorado com a do subgrupo não monitorado para radiação gama e X. Resultados: A análise externa de mortalidade mostrou RMP=0,224 (IC95% 0,208-0,240) e o efeito do trabalhador sadio, enquanto a análise interna de mortalidade mostrou RMP = 0,685 (IC95% 0,618-0,758). Conclusão: Este estudo mostrou menor mortalidade por câncer entre os trabalhadores expostos quando comparada com a mortalidade da população geral e o efeito do trabalhador sadio. Entre os trabalhadores monitorados para radiação gama e X, a mortalidade por câncer foi menor quando comparada com a dos não monitorados.
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Introducción: El uso de radiografías como elemento complementario para el diagnóstico es fundamental para la práctica profesional de todo cirujano dentista. Por tanto, es importante conocer no solo los beneficios de la radiología oral y los fundamentos de protección radiológica, sino también determinar su nivel de aplicación o la adherencia frente al cumplimiento de los aspectos normativos que regulan el uso de la radiación ionizante en odontología. Objetivo: Relacionar el conocimiento sobre los cuidados en radiología bucal, las ventajas y los peligros en la toma de radiografías con el cumplimiento de las normas de protección radiológica y radiación ionizante en estudiantes de odontología de una clínica dental docente. Métodos: La población de estudio estuvo constituida por 180 estudiantes del cuarto año de la carrera de odontología, que emplearon los equipos radiológicos en la clínica docente asistencial durante los años 2019 (segundo semestre) y 2020 (primer trimestre). Se tomó como muestra representativa a 104 estudiantes, incorporados al estudio mediante muestreo aleatorio simple. Se aplicaron dos instrumentos de recolección de datos, uno para evaluar el conocimiento (cuestionario) y otro para verificar el cumplimiento de normas (lista de chequeo) sobre la protección radiológica y el diagnóstico por imágenes en la práctica odontológica. Para el análisis estadístico se aplicó la prueba estadística chi cuadrado con un nivel de significancia del 95 %. Resultados: No se encontró relación estadísticamente significativa (p = 0,30) entre el conocimiento teórico sobre la protección radiológica y el diagnóstico por imágenes, respecto el cumplimiento de las normas que regulan su aplicación (p > 0,05). El 90 % de participantes tienen conocimientos entre regulares y excelentes. Sin embargo, solo el 32 % cumple las normas técnicas de protección sobre radiación ionizante en su práctica clínica. Conclusión: Los estudiantes de odontología tienen suficiente conocimiento sobre protección radiológica y diagnóstico por imágenes. Sin embargo, este conocimiento no se refleja en prácticas adheridas a las normas.
Introduction: The use of radiographs as a complementary element for diagnosis is fundamental to the professional practice of every dental surgeon. Therefore, it is important to know not only the benefits of oral radiology and the fundamentals of radiological protection, but also to determine their level of application or adherence to compliance with the regulatory aspects that regulate the use of ionizing radiation in dentistry. Objective: To relate the knowledge of oral radiology care, the advantages and dangers in taking radiographs with compliance with the norms of radiological protection and ionizing radiation in dental students of a dental teaching clinic. Methods: The study population consisted of 180 fourth year dental students who used the radiological equipment in the teaching dental clinic during 2019 (second semester) and 2020 (first quarter). A representative sample of 104 students was taken, incorporated into the study by simple random sampling. Two data collection instruments were applied, one to evaluate knowledge (questionnaire) and the other to verify compliance with standards (checklist) on radiological protection and diagnostic imaging in dental practice. For the statistical analysis the chi-square statistical test was applied with a significance level of 95 %. Results: No statistically significant relationship was found (p = 0.30) between theoretical knowledge of radiological protection and diagnostic imaging with respect to compliance with the norms that regulate its application (p > 0.05). Ninety percent of participants have fair to excellent knowledge. However, only 32 % comply with the technical norms of ionizing radiation protection in their clinical practice. Conclusion: Dental students have sufficient knowledge of radiation protection and diagnostic imaging. However, this knowledge is not reflected in practices that adhere to the standards.
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HumainsRésumé
OBJECTIVE@#To investigate the fate and underlying mechanisms of G2 phase arrest in cancer cells elicited by ionizing radiation (IR).@*METHODS@#Human melanoma A375 and 92-1 cells were treated with X-rays radiation or Aurora A inhibitor MLN8237 (MLN) and/or p21 depletion by small interfering RNA (siRNA). Cell cycle distribution was determined using flow cytometry and a fluorescent ubiquitin-based cell cycle indicator (FUCCI) system combined with histone H3 phosphorylation at Ser10 (pS10 H3) detection. Senescence was assessed using senescence-associated-β-galactosidase (SA-β-Gal), Ki67, and γH2AX staining. Protein expression levels were determined using western blotting.@*RESULTS@#Tumor cells suffered severe DNA damage and underwent G2 arrest after IR treatment. The damaged cells did not successfully enter M phase nor were they stably blocked at G2 phase but underwent mitotic skipping and entered G1 phase as tetraploid cells, ultimately leading to senescence in G1. During this process, the p53/p21 pathway is hyperactivated. Accompanying p21 accumulation, Aurora A kinase levels declined sharply. MLN treatment confirmed that Aurora A kinase activity is essential for mitosis skipping and senescence induction.@*CONCLUSION@#Persistent p21 activation during IR-induced G2 phase blockade drives Aurora A kinase degradation, leading to senescence via mitotic skipping.
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Humains , Aurora kinase A/métabolisme , Lignée cellulaire tumorale , Mitose , Cycle cellulaire , Rayonnement ionisant , Petit ARN interférent/métabolisme , Inhibiteur p21 de kinase cycline-dépendante/métabolismeRésumé
Due to the continuous development of nuclear power technology and the wide application of ionizing radiation in China, an increasing number of occupational groups and the general public have been exposed to the low-dose ionizing radiation environment. Consequently, research has focused on related health effects (carcinogenic and non-carcinogenic effects). There is no consensus on the health effects of long-term low-dose ionizing radiation exposure on populations. This article reviews the health effects of low-dose ionizing radiation identified worldwide to provide a scientific basis for investigating the mechanisms of such effects and developing population protection strategies.
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With social development and technology progress, there is an increasing use of daily electronic products and radioactive medical devices, which increases the risk of exposure to radiation in medical practices, daily life activities, and work. Notably, the effects of radiation exposure on pregnant women and their offspring have attracted increasing attention. Comprehensive and accurate assessment and intervention of the effects of radiation exposure on pregnant women and their offspring are of great significance to reduce birth defects and achieve eugenics. This article reviews the effects of radiation exposure during pregnancy on offspring health based on animal experiments and clinical studies, and describes the possible mechanisms, so as to provide the basis for further studies.
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With the rapid development and widespread application of medical imaging technologies, ionizing radiation has become unavoidable in human lives. Accurate assessment of healthy effects of ionizing radiation is of great significance to reduce the risk of exposure to radiation. Increasing evidence has proven the impact of ionizing radiation on cardiovascular systems. This article reviews the effects of ionizing radiation on heart, blood pressure, and blood vessels and the possible mechanisms, so as to provide insights into implementation of targeted protective interventions and reduction of ionizing radiation hazard.
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Radiation induced lung injury (RILI) is a common complication after radiation therapy of breast tumors and bone marrow transplantation pretreatment, and it is a critical limiting factor of radiotherapy doses in patients. Once RILI progresses to the radiation-induced pulmonary fibrosis stage, it seriously reduces the patient’s quality of life, while causing the patient’s respiratory failure and eventually leading to death. Ionizing radiation (IR) can induce cell injuries, including apoptosis, epithelial-mesenchymal transition, senescence, pyroptosis and ferroptosis, and these injuries can play an important role in the occurrence and development of radioactive lung injury. Starting from discussion of the occurrence of different forms of injury in different cells after IR stimulation, this review summarizes the pathogenesis of RILI and its clinical prevention and treatment.
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Ionizing radiation has been widely used for diagnosis and treatment of diseases. Nevertheless, radiation exposure may increase the risk of skin, cardiovascular system, hematological system, and metabolic disorders, and even the risk of cancers. Rational use of ionizing radiation improves prognosis and facilitates biomedical research, while misuse or overuse may result in serious consequences. Scientific and objective assessment of health hazards of medical radiation and establishment of effective protective interventions are of great importance to control the risk of radiation exposure. This article reviews the health hazards and protective measures of medical radiation.
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Objective To propose specific suggestions for exemption management of X-ray devices applying for exemption management. Methods The weight analysis of influence of shielding thickness and tube voltage on the radiation dose leakage of low-energy X-ray devices was carried out through test analysis, and the radiation status of 50 X-ray devices applied for end-user exemption in Shenzhen, China was investigated. Results There was no significant correlation between the ambient dose equivalent rate and the tube voltage and tube current of the X-ray device. The ambient dose equivalent rate of 50 X-ray devices was 0.16-1.20 μSv/h. Among them, 8 X-ray devices had radiation dose leakage, that is, the ambient dose equivalent rate was greater than 0.36 μSv/h; the ambient dose equivalent rate of one X-ray device was 1.2 μSv/h, exceeding exemption management requirements. Conclusion Applications for exemption management and filing of X-ray devices should be treated differently, and their own shielding effect and inherent safety have a greater impact on radiation safety, which should be focused on.
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Objective To investigate the occupational health status of radiation workers in Dezhou, China, explore the effects of low-dose ionizing radiation on the health of radiation workers, and provide a basis for improving the health of radiation workers. Methods A total of 1101 radiation workers in Dezhou who underwent occupational health examination in 2021 were selected. The effects of physical examination type, type of work, sex, length of service, and age on the health status of radiation workers were compared and analyzed. Results The abnormal rates of abdominal color Doppler ultrasound and eye lens were significantly higher in pre-post radiation workers than in radiation works (P < 0.05). The abnormal rates of eye lens increased with the length of service in radiation workers (P < 0.05). The abnormal rate of abdominal color Doppler ultrasound in male workers was higher than that in female workers, while the abnormal rates of blood routine and thyroid function were higher in female workers than in male workers (P < 0.05). Conclusion The abdominal rates of color Doppler ultrasound and eye lens are relatively high among radiation workers in Dezhou. It is necessary to improve the protection awareness and strengthen the level of radiation protection, so as to ensure the occupational health of radiation workers.
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Objective@# To investigate the thyroid functions and influencing factors among radiation workers in Wuhan City, so as to provide insights into occupational health monitoring among radiation workers.@*Methods @#Radiation workers receiving physical examinations in Wuhan Prevention and Treatment Center for Occupational Diseases from January to October 2022 were enrolled, and participants' gender, age, smoking, alcohol consumption, medical history, medication use, types of occupational radiation and work duration were collected. Triiodothyronine (TT3), thyroxine (TT4), free thyroxine (FT4), free triiodothyronine (FT3) and thyroid stimulating hormone (TSH) were measured using a magnetic microparticle-based chemiluminescence immunoassay. Personnel dose equivalent was monitored using thermoluminescent dosimetry, and annual cumulative radiation dose was estimated. Factors affecting thyroid function were identified using a multivariable linear regression model.@*Results@#Totally 978 radiation workers were recruited, with a median age of 32.00 (interquartile range, 10.00) years, and including 782 men (79.96%) and 196 women (20.04%). There were 246 smokers (25.15%), 257 workers with alcohol consumption (26.28%) and 489 with a history of radiation work (50.00%). The median annual cumulative radiation dose was 0.20 (interquartile range, 0.24) mSv. The percentage of abnormal thyroid function was 14.72%. Multivariable logistic regression analysis showed that women (OR=1.925, 95%CI: 1.061-3.490), history of radiation work (OR=2.810, 95%CI: 1.119-7.057) and involving in medical application (OR=1.915, 95%CI: 1.101-3.332) were associated with abnormal thyroid function.@*Conclusions@#The percentage of abnormal thyroid function was 14.72% among radiation workers in Wuhan City. History of exposure to ionizing radiation, types of occupational radiation and gender were main factors affecting thyroid function.
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@#The rapid advances in technology and medicine have greatly facilitated the application of ionizing radiation. Clinically, radiotherapy is one of the major treatments for malignant tumors. However, besides killing tumor cells, ionizing radiation inevitably leads to radiation damage and even death of normal cells. How ionizing radiation causes cell death and the forms of cell death have always been important research topics in this field. Recently, several forms of cell death induced by irradiation have been discovered. Apart from apoptosis, pyroptosis, necroptosis, ferroptosis, autophagic cell death, and methuosis have gradually become research hotspots, and provide new targets for the development of radioprotective drugs and radiosensitizers. In this review, we summarize various forms of ionizing radiation-induced cell death and related molecular mechanisms. We also introduce the latest progress in radiation protection and radiosensitization based on these cell death mechanisms. This review will provide a reference for the research and development of radioprotective drugs and radiosensitizers in the future.
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@#<b>Objective</b> To investigate the synergistic protective effects of WR-2721 combined with lentinan and cytokines against radiation damage in mice, and to provide a new treatment for acute radiation injury. <b>Methods</b> Seventy Institute of Cancer Research mice were divided into seven groups: a control group, a model group, WR-2721 group, Lentinan & cytokine group, WR-2721 & Lentinan group, WR-2721 & cytokine group and WR-2721 & Lentinan & cytokine group. All groups except the control group were irradiated with <sup>60</sup>Co γ-rays at a dose rate of 0.8 Gy/min and a cumulative dose of 5.0 Gy. The mice were sacrificed by cervical dislocation 14 d after irradiation to measure their spleen index, thymus index, and serum levels of superoxide dismutase (SOD), malondialdehyde (MDA), interleukin-11 (IL-11), and tumor necrosis factor-alpha (TNF-α). <b>Results</b> For the mice treated with WR-2721, lentinan, and cytokines, the spleen index was 7.33 ± 2.84, the thymus index was 1.70 ± 0.30, the serum SOD level was 114.0 ± 8.3, the MDA level was 7.33 ± 1.16, the IL-11 level was 155.8 ± 49.4, and the TNF-α level was 174.0 ± 37.8. All these indicators except the spleen index in the combination group significantly differed from those of the model group (<i>P</i> < 0.05 or 0.01), indicating the combined treatment promoted recovery from radiation damage. <b>Conclusion</b> WR-2721 combined with lentinan and cytokines has significant synergistic protective effects, which is a promising treatment for acute radiation injury.
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@#<b>Objective</b> To investigate the effects of lowdose ionizing radiation (LDIR) on oxidative stress and damage repair in human bronchial epithelial (HBE) cells. <b>Methods</b> HBE cells were divided into 0, 50, 100, and 200 mGy groups, and cultured for 24 and 48 h after X-ray irradiation, respectively. The cell viability, levels of glutathione (GSH), malondialdehyde (MDA), and 8-hydroxy-2’-deoxyguanosine (8-OHdG), and transcriptional levels of DNA damage repair genes <i>PPP2R2D</i> and <i>TP53</i> were measured. <b>Results</b> At 24 h after irradiation, there was no significant difference in the cell viability between the dose groups and the control group (<i>P</i> > 0.05); all dose groups had significantly increased MDA level, dose-dependently decreased GSH level, dose-dependently increased 8-OHdG level, and significantly increased mRNA level of <i>PPP2R2D</i> gene (all <i>P</i> < 0.05); the mRNA expression level of <i>TP53</i> gene was significantly increased in the 50 mGy group (<i>P</i> < 0.05). At 48 h after irradiation, there were the highest cell viability, significantly decreased MDA and 8-OHdG levels, and significantly increased mRNA expression levels of <i>PPP2R2D</i> and <i>TP53</i> genes in the 50 mGy group compared with the control group (all <i>P</i> < 0.05); the GSH level in the 100 mGy group was significantly increased (<i>P</i> < 0.05). <b>Conclusion</b> LDIR, especially radiation at 50 mGy, can affect the oxidative-antioxidant level in HBE cells and the transcript-level differential expression of DNA damage repair genes.
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ObjectiveTo investigate the current status and high-risk factors of chromosomal aberrations in peripheral blood lymphocytes （PBL） of radiation workers in Hainan Province. MethodsA total of 200 radiological workers who underwent occupational health examination in Hainan Provincial Hospital of Traditional Chinese Medicine from January 2021 to December 2021 were selected to collect the occupational health examination data and the rate of PBL chromosomal aberrations. The influencing factors of PBL chromosomal aberrations were analyzed by logistic regression model. The predictive value of logistic regression prediction model on PBL chromosomal aberrations were determined by using the reciver operator characteristic （ROC） curve. ResultsA total of 20 000 cells （100 cells/person） were tested. The chromosomal aberration rate was 0.37% （74/20 000） and the PBL chromosomal aberration rate in the subjects was 6.00% （12/200）. Univariate analysis showed that PBL chromosomal aberrations in radiological workers were related to age， length of service， type of work and education （all P<0.05）， but not to gender （P>0.05）. The logistic regression prediction model was constructed based on the influencing factors， with χ2=9.413， df=9， P=0.852， suggesting a good model fit. The logistic regression prediction model predicted the area under the curve （AUC） for the occurrence of PBL chromosomal aberrations in radiation workers was 0.914 （95%CI： 0.866‒0.949）， with a cut-off value of 3.05， corresponding to a prediction sensitivity and specificity of 100.00% and 75.98%， respectively. ConclusionThe incidence of PBL chromosomal aberrations in radiological workers in Hainan Province was 6.00%， with age， working age and job type as high-risk factors and education level as a protective factor. The prediction model constructed by the above factors can provide a reliable basis for clinical prediction of PBL chromosomal aberrations in radiological workers.
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OBJECTIVE@#To explore the chronic injury and its possible mechanism of ionizing radiation on multipotent hematopoietic progenitor cells (MPPs) by determining the related indicators of MPPs in bone marrow of mice post-radiation.@*METHODS@#Sixteen C57BL/6 adult mice were randomly divided into normal control and irradiation groups, 8 mice in each group. The mice in irradiation group were exposed to 6 Gy X-ray. The proportion of bone marrow MPPs, their apoptosis and proliferation 2 months after irradiation were detected by flow cytometry. Mitochondrial activity and levels of reactive oxygen species (ROS) in each MPPs population were detected by Mitotracker Red and DCFDA probes, and the senescent state of MPPs in the bone marrow was analyzed.@*RESULTS@#Ionizing radiation could reduce the proportion of MPPs in mouse bone marrow. The proportions and numbers of MPP1, MPP3 and MPP4 in the bone marrow were significantly decreased after whole-body irradiation with 6 Gy X-ray (P<0.05). In addition, radiation significantly reduced the colony-forming capacity of MPPs in bone marrow (P<0.05), the proportions of apoptotic cells in the MPP1 and MPP4 cell populations increased significantly in the bone marrow (P<0.05). The activity of mitochondria was significantly reduced in the bone marrow MPP2, MPP3 and MPP4 cell populations compared with that of the control group (P<0.05). It was also found that the radiation could significantly increase the ROS levels of MPPs in bone marrow, and the content of ROS in the MPP2, MPP3 and MPP4 cell population of the bone marrow was significantly increased(P<0.05). The senescent cells ratios of MPP1, MPP3 and MPP4 cells in the bone marrow after irradiation were significantly higher than those in the control group (P<0.05).@*CONCLUSION@#Ionizing radiation can cause chronic MPPs damage in mice, which is closely associated with persistent oxidative stress, cells apoptosis, and cellular senescence.
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Souris , Animaux , Moelle osseuse , Espèces réactives de l'oxygène , Souris de lignée C57BL , Cellules souches hématopoïétiques , Irradiation corporelle totale , Rayonnement ionisant , Cellules de la moelle osseuseRésumé
Este trabalho teve por objetivo analisar os aspectos sociodemográficos e da situação de saúde dos indivíduos expostos ao Césio 137, que constam com cadastro ativo no Sistema de Informação ao Radioacidentado (SISRAD) do Centro de Assistência aos Radioacidentados (CARA). Métodos: Trata-se de um estudo descritivo, com análise transversal, realizado no período de outubro de 2019 a fevereiro de 2020 e que contempla dados registrados desde o ano de 1987. O público-alvo da pesquisa consistiu em indivíduos expostos de forma direta e indireta ao Césio 137 na cidade de Goiânia-Goiás, e que se encontram devidamente cadastrados no CARA. Levou-se em consideração aspectos sociodemográficos, a fim de construir o perfil dos pacientes. Realizado esse processo, procedeu-se à classificação e distribuição dos pacientes, através de critérios como a forma de contato e a dose de exposição. O levantamento de dados foi executado pela análise dos prontuários no SISRAD. Resultados e Conclusões: nos grupos mais jovens não foram identificados cânceres precoces ou malformações nos Grupos NGI e NGII, mas existem relatos que conflitam com as declarações de óbitos dos grupos GI e GII, o que trouxe dificuldades para uma análise estratificada e detalhada. As doenças psíquicas, apresentam maior prevalência, seguidas de causas associadas a hipertensão e a diabetes. Verificou-se a importância da análise de saúde dos radioacidentados como ferramenta de planejamento, preparação e avaliação dos grupos de risco
This study aimed to analyze the sociodemographic aspects and the health situation of individuals exposed to Cesium 137, who have an active record in the Information System for Radio Accidents (SISRAD) of the Assistance Center for Radio Accidents (CARA). Methods: This is a descriptive study, with cross-sectional analysis, carried out from October 2019 to February 2020 and which includes data recorded since 1987. The target audience of the research consisted of individuals exposed directly and indirect exposure to Cesium 137 in the city of Goiânia-Goiás, and who are duly registered with the CARA. Sociodemographic aspects were taken into account in order to build the profile of patients. Once this process was completed, the patients were classified and distributed using criteria such as the form of contact and the dose of exposure. Data collection was carried out by analyzing the medical records in SISRAD. Results and Conclusions: In the younger groups, no early cancers or malformations were identified in Groups NGI and NGII, but there are reports that conflict with the death certificates of groups GI and GII, which brought difficulties for a stratified and detailed analysis. Mental illnesses are more prevalent, followed by causes associated with hypertension and diabetes. The importance of analyzing the health of radio-accidents as a tool for planning, preparing and evaluating risk groups was verified