The genetic polymorphism of DNA repair gene plays some important role in regulating individual sensitivity to ionizing radiation, maintaining DNA integrity, and preventing cancer and DNA damage.XRCC1 ...as one of the members ofbase excision repair (BER) is involved in the repairement of oxidized bases and single-strand breaks DNA after exposure by ROS, including ionizing radiation. This study was aimed to examine the correlation between XRCC1 exon 6 gene polymorphism and MN frequency in radiation workers and their relation to age, gender, smoking status and years of exposure. This study involved 81 hospital radiation workers and 20 controls from several hospitals in Indonesia. Genotyping of XRCC1exon 6 gene polymorphism and MN assay were performed using Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) and Cytokinesis-Block Micronucleus assay (CBMN assay), respectively. The results indicated that MN frequency was significantly higherin the exposed workers than in the controls (15.38±7.72 versus 9±5.49; p = 0.001).Radiation workers with heterozygous alleles for XRCC1 polymorphisms showed a significantly higher MN frequency than controls with the same genotypes (17.5±8.36 versus 7.44±5.05; p = 0.002). The confounding factors, like gender and age, were significantly associated with increased MN frequency both in radiation workers and controls. Smoking status was significantly associated with MN frequency in the controls only, while years of exposure did not affect MN frequency either in radiation workers or controls. These results suggest that the genetic polymorphism of XRCC1 gene exon 6 with a mutant heterozygous/ CT variant demonstrated an association with the extent of DNA damage in the hospital radiation workers in this study. In the subsequent studies, it is necessary to examine the DNA repair genes polymorphism in populations with controlled non-genetic factors, such as lifestyles, environments, and exercises that affect the MN frequency as a biomarker of DNA damage.
Since the International Commission on Radiological Protection recommended reducing the occupational equivalent dose limit for the lens of the eye in 2011, there have been extensive discussions in ...various countries. This paper reviews the current situation in radiation protection of the ocular lens and the discussions on the potential impact of the new lens dose limit in Japan. Topics include historical changes to the lens dose limit, the current situation with occupational lens exposures (e.g., in medical workers, nuclear workers, and Fukushima nuclear power plant workers) and measurements, and the current status of biological studies and epidemiological studies on radiation cataracts. Our focus is on the situation in Japan, but we believe such information sharing will be useful in many other countries.
In our work, we have used mathematical modeling to determine the uranium concentrations in the urine samples of workers in radiation field according to the number of working years. The work aims at ...constructing a mathematical model to determine the uranium concentrations in the urine of the radiation workers based on the number of working years. The obtained values, which have been determined by the constructed model, gave reasonable results and a good agreement with the other experimental results .
The carcinogenic effects of low radiation doses have not been fully understood until now. Studies on individuals that are occupationally exposed to low radiation doses can help to address this ...question. This study assesses the micronucleus (MN) frequencies as indicator of DNA damage in radiation workers that are occupationally exposed to low radiation dose. The influence of single nucleotide polymorphisms (SNPs) in XRCC3 gene on the frequency of micronuclei was also evaluated in this study. The effects of confounding factors of gender, age, and smoking status on MN frequencies was assessed in all samples. A total of 60 subjects consisting of 30 radiation workers from Center of Multipurpose Reactor (CMPR), National Nuclear Energy Agency (NNEA) of Indonesia, and 30 control samples were enrolled in this study. The results showed that the difference between MN frequency in radiation workers and in control samples was not statistically significant 0.019 vs. 0.021; p = 0.549. Age and smoking status did not affect micronucleus frequencies in all samples (p = 0.723 and 0.828). Micronucleus frequencies in females were higher compared to males, even though the difference was not significant (p = 0.3). Radiation workers with variant alleles for XRCC3 olymorphism did not showed higher MN frequencies compared to the controls with the same genotypes. The small numbers of samples with XRCC3 variant alleles found in this study possibly contributed to the insignificant difference of MN frequencies between wild-type allele (Thr/Thr) and mutant alleles (Thr/Met or Met/Met). Further investigations using larger sample sizes and MN assay in combination with human pan-centromeric probe should be conducted to validate this study results. Other SNP in XRCC3 gene also should be evaluated to find out the association between SNP and MN frequencies.
There are evidences of association between occupational radiation exposure, cytogenetic alterations and the increase in cancer rates. It is known that the probability of carcinogenesis is greater in ...populations exposed to radiation, since ionizing radiation can raise the frequency of chromosomal aberration and spontaneous mutations.
Our purpose was to assess the role of chromosomal aberrations and oxidative DNA adduct 8-hydroxy-2-deoxyguanosine (8-OHdG) as biomarkers of radiation injury in individuals occupationally exposed to ionizing radiation.
and Methods: Blood samples were collected from 60 radiation workers and 30 healthy volunteers age and sex matched as control group who had never worked in radiation-related jobs. Chromosomal aberrations in peripheral blood lymphocytes were assayed by conventional cytogenetic technique and serum levels of 8-OHdG was measured by enzyme linked immunossorbent assay (ELISA).
The incidence of all types of chromosomal aberrations was significantly higher in all exposed groups than in controls with the highest rate of chromosomal aberrations in the industrial radiographers. Serum 8-OHdG in all radiation workers was significantly higher than in control group. There was a significant higher values among industrial radiographers compared to diagnostic radiologists or radiotherapists. Significantly lower mean corpuscular volume (M.C.V) was found among radiation workers versus the controls reflecting erythrocyte microcytosis.
Scoring of chromosome aberrations such as breaks, fragments and dicentrics is a reliable method to detect previous exposure to ionizing radiation. This type of monitoring may be used as a biological dosimeter instead of physical dosimetry.8-OHdG is a useful oxidative DNA marker among radiation workers and those exposed to environmental carcinogens.
Top Score for the Radiology Boards: Q & A for the Core and Certifying Exams is the ideal diagnostic radiology board prep resource. Written by radiologist Alan Weissman, with contributions from dozens ...of leading experts at renowned institutions, Top Score has a simple ambition: to improve your test scores. The book covers all exam categories, including non-interpretive skills (NIS), physics, safety, breast, cardiac, diagnostic radiology, gastrointestinal, genitourinary, interventional, musculoskeletal, neuroradiology, nuclear, pediatrics, thoracic, ultrasound/reproductive/endocrinology, vascular, and general radiology. Chapters are composed of four types of test cases of varying focus and complexity, each on a two-page spread. Essentials starts with a patient presentation, followed by board-type multiple-choice questions. Details begins with a case presentation, followed by 10 rapid-fire questions, enabling brisk, high-volume learning. Image Rich presents multiple images that require accurate identification, enabling accelerated, high-volume image assessment practice. More Challenging follows the same format as Essentials but adds a higher degree of difficulty. Key highlights * High-quality, board-type Q with detailed answer explanations * High yield "Top Tips" for each case * Special radiology artifacts section * Image Rich and Details sections aid in rapid and lasting topic mastery * Comprehensive review, covering all sections tested by the American Board of Radiology * Written by experienced, expert question writers * NIS chapter emphasizes proficiency in vital practice-related skills This quintessential home-study guide will help radiology residents and fellows prep for and ace both the certifying and core exams.
Objectives
This study aimed to investigate changes in peripheral blood cells of radiation workers and explore the impact of long‐term ionizing radiation (IR) on human peripheral hemogram.
Methods
...With a cohort method, we selected 1,392 radiation workers (case group) and 1,430 non‐health‐ray‐exposure history persons (control group) to detect and analyze their peripheral hemogram. FAITH3000 automatic biochemical analyzer was used for blood testing. Examination of peripheral hemogram includes the examination of white blood cells (WBCs), platelet (PLTs), red blood cells (RBCs), hemoglobin (Hb), lymphocytes (LYMs), and mononuclear cells (MOs). The data analysis was conducted with software SPSS19.0.
Results
All the peripheral hemogram indicators (WBCs, RBCs, Hb, PLTs, LYMs, and MOs) in the case group, in accordance with the order of radiology diagnostic medical group, industrial inspection group, petroleum logging group, and radiotherapy medical group, showed a significant decreasing trend and were lower than those in the control group (all P < 0.05). Besides, with the increase of radiation seniority and accumulative radiation dose, all the peripheral hemogram indicators (WBCs, RBCs, Hb, PLTs, LYMs, and MOs) in the case group dramatically decreased and were lower than those in the control group (all P < 0.05). Seniority was in negative association with the expressions of WBCs, PLTs, RBCs, Hb, LYMs, and MOs and radiation dose with Hb, LYMs, and MOs (all P < 0.05).
Conclusion
Long‐term IR has some effects on the health of radiation workers, thus protective measures should be further strengthened.
•Great variation and uncertainties regarding the occupational dose levels result in great uncertainties in foetal dose assessments.•Potential exposures due to accidents have to be considered and ...taken into account.•ICRP constraints for foetuses and breastfed children should be followed.•Work with no restrictions as well as work not to be done during pregnancy and breastfeeding should be unambiguously define.•Declaration of pregnancy or breastfeeding is of fundamental importance.
This paper describes issues of concern for protecting foetuses and breast-fed children of occupationally exposed women in nuclear medicine from unnecessary exposure of ionising radiation. The protection principle is to ensure the same level of protection for the foetus and child as for the general public. Therefore international radiation protection standards recommend a dose constraint of 1mSv to a foetus during the remaining time of pregnancy after it is known/declared and a yearly dose constraint of 1mSv to a breast-fed child. It is not self-evident how to guarantee this level of radiation protection.
The exposure situation in nuclear medicine is complex. Exploring existing reported occupational exposure levels suggests great variability between work tasks and facilities. The standards and guidelines found give no detailed advice. Therefore each facility needs to systematically review external and internal exposure levels in order to plan appropriate protection measures and issue their own guidelines and rules. One strategy might be that each facility defines tasks that do not require any restrictions and lists such duties that are not suitable to do when pregnant or breastfeeding, taking also potential exposure levels into consideration. This paper gives examples of such types of work.
Information to the staff about the necessity of declaring pregnancy or breastfeeding is of fundamental importance. The internal policies issued by the hospital management should make clear the basis for taking care of pregnant and breastfeeding employees.
Time-course study of individual dose equivalents of 2-deoxy-2-F-18fluoro-
d
-glucose positron emission tomography (
18
F-FDG PET) was conducted in different hospital workers, and the daily work ...duties were analyzed. For the measurements, a semiconductor dosimeter was used. The values at intervals of 1 min and 1 h, the monthly cumulative and daily cumulative doses, and trend graphs were acquired with dedicated software and displayed on the reader. The following radiation workers with duties involving maximum external exposure work were included: doctors making diagnoses (4.8 μSv/procedure), nurses removing injection needles (3.1 μSv/procedure), pharmacists performing quality control tests (2.9 μSv/procedure), nuclear medicine technologists assisting patient positioning (6.5 μSv/procedure), and cyclotron engineers performing daily checks (13.4 μSv/procedure). The results of analysis of daily work duties revealed the influencing factors of external exposure dose. To reduce the external exposure dose, investigators should shorten the patient’s contact time with the
18
F-FDG source or patient tracer.
Periodic medical examinations of radiation workers are routinely conducted in many countries. Although low dose radiation (LDR) is not expected to cause a significant effect on blood count, the ...periodic examination usually includes reviewing the work history, general medical history, a physical examination and collecting a blood sample. Despite lymphocytes are the most sensitive cells to radiation, their counts do not show any significant change as long as the radiation level is less than a few hundreds of millisievert (mSv). In spite of this, in Iran, radiation workers, even those who work in diagnostic radiology departments, are regularly examined for blood count changes.
After a detailed search in PubMed, ISI, Scopus, SID and Google Scholar, only 12 out of 650 articles matched our criteria. A review of these 12 reports was conducted. The full texts were fully reviewed by the authors.
The complete blood count (CBC) test has a very low efficacy in evaluation of the adverse health effects of ionizing radiation in radiation workers. Therefore, finding alternative methods with a higher efficacy is recommended.
CBC tests cannot be introduced as valid markers of potential radiation effects in most occupational exposures. Given this consideration, in periodic tests of radiation workers, cytogenetic tests can be the gold-standard method. In particular, due to its relatively low cost and good sensitivity and specificity, the dicentric assay can be promising. Moreover, the simple and rapid evaluation of micronuclei by fast automated scoring systems can be a good alternative for current low efficacy CBC tests.
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