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Purpose The aim of this study was to determine the prevalence of radiation-induced cataracts and its correlation with radiation exposure dose and radiation protection equipment use among radiation workers of interventional cardiology. Methods This is a cross-sectional and retrospective case–control study. We included 180 subjects. The prevalence of radiation-induced cataracts was assessed using Scheimpflug analysis on the Pentacam-Oculus device. Individual cumulative radiation exposure dose and radiation protection equipment use were identified from questionnaires and personal dosimeters. Results The prevalence of radiation-induced cataracts was 16.7%. The median cumulative radiation dose was 0.8 (0.1–35.6) Gy. A positive correlation was found between cumulative radiation dose and lens density (R Spearman = 0.64). We found 83.9% of subjects used ceiling-suspended shields in 71 to 100% of their working period. However, most subjects (40.6%) did not wear protective eyewear. There was a statistically significant increasing risk of radiation-induced cataracts and unresponsive use of radiation protection equipment. Subjects using ceiling-suspended shield in only 31 to 50% of their working period increased their cataract risk by 10.8 times (95% confidence interval [CI]: 1.05–111.49, p = 0.044). Meanwhile, subjects using protective eyewear in only 51 to 70% of their working period increased their cataract risk by 8.64 times (p = 0.001). Subjects who did not wear protective eyewear had an odd ratio of 164.3 (95% CI: 19.81–1363) compared to those who did. Conclusion Radiation-induced cataracts among radiation workers of interventional cardiology depended on the radiation exposure dose and the use of radiation protection equipment. [ABSTRACT FROM AUTHOR]

The Korean Radiation Workers Study (KRWS) cohort was established in 2022 to assess the risk of cancer and non-cancer diseases due to occupational radiation exposure. The cohort consists of 196,379 workers, with the majority being men and around 60% born before 1980. Data on cancer, non-cancer diseases, cause of death, and various confounders were obtained from national resources. The study aims to update radiation doses and disease status every 5-10 years and welcomes proposals for further data analyses. The study found that 3.1% of workers had been diagnosed with cancer, with thyroid cancer being the most prevalent type. The most common causes of death were malignant neoplasms, external causes, and circulatory diseases. The incidence of cancer and mortality was higher in men, except for thyroid cancer, which was more common in women. The cohort provided a total of 2.5 million person-years for cancer incidence and 2.8 million person-years for mortality. The Korean Radiation Workers Study (KRWS) is a large-scale national cohort study that aims to investigate the long-term health effects of radiation exposure in Korean workers. The cohort includes both retired and newly hired workers and is designed for long-term follow-up. The study collects comprehensive health information from national registries, ensuring accuracy and completeness of data. The cohort has strengths such as regular updates, availability of confounding factors, and monitoring of cancer incidence. However, limitations include a relatively small [Extracted from the article]

Introduction: Access to ionizing radiation has become widely available for diagnosis and treatment. The increased use of ionizing radiation has been associated with radiation exposure hazards for patients and radiation workers. Raising the level of radiation protection awareness is important to maintain the safety of healthcare settings. Methods: Online questionnaires were distributed to 755 healthcare workers and students at King Abdulaziz Medical City and King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia. The questionnaire consisted of 14 multiple-choice questions divided into two sections (questions related to radiation protection and common radiologic examination doses). Results: In total, 443 participants completed the questionnaire, including 142 (32%) medical students, 107 (24%) radiology technologists, 105 (24%) radiography students, and 89 (20%) physicians. Of the participants, 245 (55%) were men. A total of 74 (84%) physicians and 51 (47%) radiology technologists had more than 5 years of experience. Eleven (12%) physicians and 44 (41%) radiology technologists had 1–4 years of experience, whereas the rest had less than 1 year of experience. Only 16% of participants attended training courses on a regular basis. However, 15% of the participants thought that they had excellent knowledge of radiation protection, whereas 18% admitted that they did not have sufficient knowledge. Sixty-two percent of the questions related to radiation protection awareness were answered correctly. Forty-five percent of the participants correctly answered questions related to doses from common radiologic examinations. Only 23% and 16% of participants were aware of the noncontrast chest CT and lumbar x-ray doses, respectively. Moreover, 35% and 24% of participants did not know that pelvic MRI and abdominal ultrasound do not contribute any radiation dose, respectively. Conclusion: The results showed a knowledge gap regarding radiation protection and dose levels; therefore, periodic refresher courses are recommended for healthcare workers in order to increase the level of awareness.

This article summarizes a number of presentations from a session on "Radiation and Circulatory Effects" held during the Radiation Research Society Online 67th Annual Meeting, October 3–6 2021. Different epidemiological cohorts were analyzed with various statistical means common in epidemiology. The cohorts included the one from the U.S. Million Person Study and the Canadian Fluoroscopy Cohort Study. In addition, one of the contributions in our article relies on results from analyses of the Japanese atomic bomb survivors, Russian emergency and recovery workers and cohorts of nuclear workers. The Canadian Fluoroscopy Cohort Study data were analyzed with a larger series of linear and nonlinear dose-response models in addition to the linear no-threshold (LNT) model. The talks in this symposium showed that low/moderate acute doses at low/moderate dose rates can be associated with an increased risk of CVD, although some of the epidemiological results for occupational cohorts are equivocal. The usually only limited availability of information on well-known risk factors for circulatory disease (e.g. smoking, obesity, hypertension, diabetes, physical activity) is an important limiting factor that may bias any observed association between radiation exposure and detrimental health outcome, especially at low doses. Additional follow-up and careful dosimetric and outcome assessment are necessary and more epidemiological and experimental research is required. Obtaining reliable information on other risk factors is especially important. [ABSTRACT FROM AUTHOR]

Long-term exposure to ionizing radiation (IR) can cause dire health consequences even less than the dose limits. Previous biomonitoring studies have focused more on complete blood counts (CBCs), with non-coherent results. In this study, we aimed to investigate the association between exposure to IR and cytokine interleukin-6 (IL-6) along with hematological parameters in Tabriz megacity's radiation workers. In this hospital-based study, blood samples were taken from 33 radiation workers (exposed group) and 34 non-radiation workers (control group) in 4 hospitals. Absorbed radiation dose was measured by a personal film badge dosimeter in radiation workers. The studied biomarkers and all of the selected covariates were measured and analyzed using adjusted multiple linear regression models. The exposed doses for all radiation workers were under the dose limits (overall mean = 1.18 mSv/year). However, there was a significant association between exposure to ionizing radiation and IL-6 (49.78 vs 36.17; t = 2.4; p = 0.02) and eosinophils (0.17 vs 0.14; t = 2.02; p = 0.049). The difference between the mean of the other biomarkers in radiation workers was not statistically significant compared to the control group. This study demonstrated that long-term exposure to ionizing radiation, even under the dose limits, is related to a significantly increased level of some blood biomarkers (Il-6 and eosinophil) that, in turn, can cause subsequent health effects such as cancer. [ABSTRACT FROM AUTHOR]

Background: A monitoring for radiological technologists and radiation workers must be implemented to ensure the radiation safety. Aims: The aim of our study was to measure the occupational radiation dose for medical workers from the Department of Diagnostic Radiology, Cardiac Catheterization Laboratory, Nuclear Medicine, Dental Services, Endoscopy, and Surgery at King Abdulaziz Medical City (KAMC), Riyadh, Saudi Arabia. Materials & Methods: This study was conducted at KAMC, Ministry of National Guard-Health Affairs, Riyadh, Saudi Arabia. Across-sectional study and a suitably and structured questionnaire was adapted from the previous similar studies and monitored radiation doses designed in line with the study's objectives were collected among the different medical workers. A total of 223 medical radiation workers were involved in this study, and descriptive statistics were used to analyze the data. Results: It is noted that the diagnostic radiology department recorded the highest value of effective dose followed by cardiac catheterization laboratory and nuclear medicine and so on. The measured amount of effective dose for diagnostic radiology, cardiac catheterization laboratory, nuclear medicine, dental services, endoscopy, and surgery at KAMC was found to be 14.35, 5.23, 4.56, 3.88, 3.52, and 1.87 mSv, respectively. Conclusions: This study provide an evidence that the occupational radiation dose for all the monitored departments at KAMC are well below the international recommended dose limit (20 mSv). [ABSTRACT FROM AUTHOR]

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.

Background Medical workers are the largest group of workers occupationally exposed to low doses of ionizing radiation (IR) worldwide. Aims This review presents all the cohorts of medical workers exposed in the world and summarizes cancer risks associated with radiation exposure in this population. Methods Epidemiological studies on health professionals exposed to IR published from 1975 to 2019 were reviewed. Strength of evidence was assessed according to the modified Royal College of General Practitioners three-star system. Results Among the 16 epidemiological studies focusing on cancers from 11 cohorts among medical staff exposed to radiation, higher risks of cancer were observed for pre-1950 exposure and for medical workers who performed fluoroscopically guided interventional procedures or radionuclides procedures compared to those who did not. However, strength of evidence supporting the associations remains moderate as several methodological limits including the lack of dosimetry data, lifestyle factors and recent updates may obscure the link between medical occupational exposure and cancer occurrence. Conclusions Excess risk of cancer is suspected for high and former exposures. The more highly exposed professions, i.e. interventional physicians and nuclear medicine workers, should be monitored carefully. Collaborative projects aiming to increase the quantity and quality of information of the studied populations would be a key point [ABSTRACT FROM AUTHOR]

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Objective: People working in the hospital units such as Radiology and Nuclear Medicine are subject to higher doses of ionizing radiation than people working in other professions. We examined the association between DNA damage and ionizing radiation exposure in the personnel working in university hospital and considered different variables such as smoking, working years, gender, age. Material-Method: 48 radiation exposed personnel, aged between 20-50 years old, working in radiological units within the Süleyman Demirel University Research - Application Hospital and 51 individuals, aged between 18 and 57, who do not work in hospital, constitute our research group. Lymphocytes isolated from blood samples taken from the participants were evaluated with the comet method for DNA damage. Tail DNA percentage parameter, obtained through Open Comet program, was chosen to assess DNA damage and the results were evaluated by the One-Way Anova statistical test. Results: The results, obtained from statistical comparison of tail DNA percentage parameter, indicate that even the low dose radiation caused DNA damage and age, gender, smoking habits and working years did not show any significant differences except for dosimetry value. Increasing dosimetry value resulted in increased DNA damage. Conclusions: This work supports the previous results of biomonitoring of radiology workers chronically exposed to ionizing radiation. This means ionizing radiation is still an important DNA damaging agent despite many improvements such as exposed time reduction, working conditions and technology. [ABSTRACT FROM AUTHOR]

Background and aims: The use of imaging such as X-rays may have an important role in early diagnosis, staging, planning treatment and monitoring of patients during treatment. Radiology ward staff is at risk of low-dose occupational exposure. Therefore, this study aimed to evaluate the biological effects of low dose occupational exposure to ionizing radiation on blood cell indices of radiology ward staff employed in a governmental hospital in Tehran. Methods: In this case-control study, some blood parameters in 30 radiation workers(cases) and also30 persons who worked in other parts of the hospital were compared. Matching was done for confounding factors. The data was analyzed with software SPSS 20 (p0.05). Conclusions: The results of this study showed that the hematological parameters of radiation workers exposed to low doses of radiation may not predict the amount of radiation effects.

Background: 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. Objective: 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. Subjects: 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). Results: 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. Conclusions: 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.

In this study, the effect of ionizing radiation on 8-hydroxy-20-deoxyguanosine (8-OHdG) in human peripheral blood was investigated. Blood samples were collected from 230 radiation workers and 8 patients who underwent radiotherapy for population study. Blood samples from 2 healthy individuals were irradiated with different X-ray doses for in vitro experiment, and levels of 8-OHdG in serum and cell culture supernatants were assessed by enzyme-linked immunosorbent assay. Observations demonstrated the positive relationships between serum 8-OHdG level and radiation dose and working period were observed, and serum 8-OHdG levels were higher among interventional radiation workers than among other hospital radiation workers. In addition, 8-OHdG yields in supernatants increased, peaked at 3 Gy of radiation dose, and then decreased with further increases in radiation; the dose-response curve obtained fitted a polynomial function. By contrast, a similar trend was not found in radiotherapy patients. The present study suggests that 8-OHdG may be a useful biomarker reflecting oxidative damage among workers occupationally exposed to low-dose radiation. [ABSTRACT FROM AUTHOR]

BACKGROUND: Radioactive isotopes are used in nuclear medicine for diagnostic as well as therapeutic purpose. The procedures adopted in nuclear medicine involve handling of unsealed radionuclides and may have direct contact of fingers with unshielded vials and syringes. It is the possibility of extremities contamination while handling unsealed radioactive sources due to which occupational workers gets unwanted radiation exposure. In this regard, a study was conducted in nuclear medicine department of AECH-NORI, Islamabad to evaluate the extremities exposure of radiation workers while performing different diagnostic and treatment procedures. MATERIAL AND METHODS: During the study period approximately 90-95% procedures were performed with "mTc, 5-6% by using 131l, 1% with 201TI and 0.25-0.5 % for MIBG. Eight radiation workers (seven nuclear medicine technologists and one radio pharmacist) participated in study and extremity doses were evaluated at Hp(0.07). TLD based ring dosimeters were used to measure the occupational exposure. RESULTS: The measured minimum, maximum and average doses were found 9.24 mSv/y, 90.0 mSv/y and 37.2 mSv/y for the technologists of nuclear medicine department. The minimum, maximum and average doses for radio pharmacist were found to be 95.52 mSv/y, 312.96 mSv/y and 204 mSv/y, respectively. CONCLUSION: All eight workers were right handed and found that right hand of six workers exposed more than the left hand. The measured results clearly show that the annual extremity doses of radiation workers are within the recommended limits (500 mSv/y).1 [ABSTRACT FROM AUTHOR]

OBJECTIVE: To determine the level of improvement amongst radiation workers of both sexes regarding knowledge of ionizing radiations and principles of radiation protection both for staff and patient's while performing routine diagnostic procedures after attending a dedicated refresher course of one (01) month on Radiation awareness and protection. MATERIALS & METHOD: Forty six (46) radiation workers (38 male and 08 female) out a total 60 radiation workers participated in this refresher course and have filled the pre and post Performa on basics of ionizing radiations, cellular interaction/radio-biology, biological effects of ionizing radiations, radiation protection principles and strategies to minimize patient dose which lasts for one month. The participants were asked to fill a questionnaire comprising twenty questions before starting the sessions to know their existing knowledge. Course material prepared accordingly and the same Performa was filled from the participants after the sessions to find out the improvement after attending the course. RESULTS: Mean scores of all radiation workers in presessions assessment was 39.35% which improved to 61.95% after attending the dedicated course designed with a mean difference of 22.6% (p<0.0000001). The female radiation workers awareness level improvement was higher (pre: 36.25%, post: 59.38%) than mall workers (pre: 40.0%, post: 62.5%). The workers having intermediate and higher qualification did better (pre: 38.42%, post: 61.45%) than the ones who have only metric (pre: 43.75%, post:64.38%) and workers having relevant diploma in radiology scored (pre: 42.86%, post: 65.48%) than the workers who haven't got diploma (pre: 37.0%, post: 59.0%). CONCLUSION: The knowledge about basics of ionizing radiations and protection of both staff & patients before the sessions was not satisfactory as it should be. An improvement was found amongst the radiation workers about their knowldge and understanding after attending the dedicated course on radiation awareness designed according to their needs. The awareness amongst radiation workers can be improved by consistently conducting such sessions on radiation protection and updating them time to time about the new developments and researches in their field to boost their skills and it can be achieved with the coordination & cooperation of hospital & regulatory bodies and through concurrent efforts and planning. [ABSTRACT FROM AUTHOR]

Unstable genetic aberrations might provide a good marker for assessing genetic damage in populations exposed to low levels of ionizing radiation.The frequency of these aberrations was estimated in peripheral lymphocytes from hospital workers in Bushehr Port, occupationally exposed to low levels of ionizing radiation (54 subjects) and age and sex matched controls. A total of 34 (23 males & 11 females) subjects had unstable genetic aberrations (50 chromosomal-type & 31 chromatid type) but only 7 subjects in control group had unstable genetic aberrations. When compared with controls, exposed workers showed a significant increase in structural chromosomal-type aberrations (p

Applications involving radioisotopes and radiations reveal a great promise particularly for the welfare of the society. However, in the event of a nuclear accident, the direct and indirect effect of radionuclide and radiation transfers in soil-plant-air environment are envisaged on almost all the components of the food chain. It also assumes significance as we often overlook the fact that radiations, emitted by any radioisotope although cannot be seen or felt, interacts with matter and could alter its biochemical, biophysical and biological characteristics. The interaction of ionizing radiation with human body and consequent biological effects are well characterized and quantified using data derived from the radiation workers and/or the nuclear accidents around the world. However, radiation impact on agriculture viz a viz economic productivity are not well understood and available data is scanty, scattered and inconclusive. At the plant level the effects could be visualized at morphological, biochemical, physiological and/or biophysical levels, where the magnitude of the effected change depends heavily on the exposure dose, soil, farm management and other environmental variables. This review attempts to collate and critically analyze the available researches on how the ionizing radiation might interact with crops at the whole plant or tissue or cell level to affect economic yield under various edaphic variables where not only the productivity but also the quality of the agri-produce may become vulnerable. [ABSTRACT FROM AUTHOR]

Abstract: Ionizing radiation is known as a classical mutagen capable of inducing various kinds of stable and unstable chromosomal aberrations. The percentage of cells with chromosomal aberrations was analyzed in peripheral blood lymphocytes of occupationally exposed workers in radiotherapy, CT-scan, angiography and healthy controls. The incidence of all types of aberrations (gap, acentric fragment, dicentric and ring) in exposed subjects were higher than those observed in healthy controls (P =0.0001). However, the frequency of aberrant cells with dicentric and ring chromosome in exposed subjects were not significantly different from those in controls. To see whether there is a significant difference in the incidence of chromosomal aberrations among three groups, they were compared for all types of observed aberrations. No significant difference was found between radiotherapy and CT-scan groups (P =0.838). The percentage of aberrant cells observed, for angiography groups were significantly higher than radiotherapy (P =0.0001) and CT-scan (P =0.0001) group. Taken together these data suggest that the cumulative effects of low level chronic exposure to ionizing radiation is higher for those who occupationally exposed in angiography. [Copyright &y& Elsevier]

Ionizing radiation delivered and contrast media used during diagnostic imaging of pregnant women are major dilemmi for gynecologists and radiologists. As the overall risk of abnormality is negligible at doses received during diagnostic radiological examinations, the radiologic examination can be performed cautiously if the mother is at risk and appropriate indications for an imaging examination exist. Termination of pregnancy is rarely justified because of the risk to the conceptus from a radiological study. In this article, the frequently asked questions concerning radiation dose and its potential risks to the conceptus (embryo or fetus) associated with different radiological imaging modalities were reviewed. [ABSTRACT FROM AUTHOR]

Long-term low-dose ionizing radiation (LLIR) widely exists in human life and has been confirmed to have potential pathogenic effects on cancer and cardiovascular diseases. However, it is technically and ethically unfeasible to explore LLIR-induced phenotypic changes in the human cohort, leading to slow progress in revealing the pathogenesis of LLIR. In this work, we recruited 32 radiation workers and 18 healthy non-radiation workers from the same city with the same eating habits for radiation damage evaluation and metabolomics profiling. It was found that clear metabolic phenotypic differences existed between LLIR and non-LLIR exposed participants. Moreover, LLIR exposed workers can be further divided into two types of metabolic phenotypes, corresponding to high and low damage types respectively. 3-hydroxypropanoate and glycolaldehyde were identified as sensitive indicators to radiation damage, which specific response to the chromosomal aberration of workers and may be potential monitoring markers for LLIR protection. Taurine metabolism-related pathways were identified as the main differential metabolic pathway under LLIR inducing, which had been confirmed to have a response to acute or chronic radiation exposure. We expect our study can be helpful to LLIR damage monitoring and symptomatic intervention in the future. [Display omitted] • There are distinct metabolic phenotypic differences between radiation workers and health subjects. • Radiation workers with low or high radiation damage shown differential metabolic phenotype. • 3-Hydroxypropanoate and glycolaldehyde were identified with specific response to chromosomal aberration. • Taurine metabolism related pathways were the main differential metabolic pathway induced under LLIR exposure. [ABSTRACT FROM AUTHOR]

This study uses record linkage between the National Registry of Childhood Tumours (NRCT) and the National Registry for Radiation Workers to re-assess our earlier finding that the offspring of women radiation workers exposed to ionising radiation before the child's conception may be at an increased risk of childhood cancer. An additional 16,964 childhood cancer patients taken from the NRCT, together with the same number of matched controls, are included. Pooled analyses, based on the new and original datasets, include 52,612 cases and their matched controls. Relative risks (RRs) for maternal employment as a radiation worker, maternal exposure or not during the relevant pregnancy and pattern of employment relative to conception and diagnosis dates were calculated.The new data provide no evidence of an increased risk of childhood cancer associated with maternal preconception radiation work and thus do not support our earlier finding of a raised risk in the offspring of female radiation workers. Considering the pooled data, a weak association was found between maternal radiation work during pregnancy and childhood cancer in offspring although the evidence is limited by the small numbers of linked cases and controls. [ABSTRACT FROM AUTHOR]

Cell response to genotoxic agents is complex and involves the participation of different classes of genes (DNA repair, cell cycle control, signal transduction, apoptosis and oncogenesis). In this report, we present three approaches to document gene expression profiles, dealing with the evaluation of cellular responses to genotoxic agents (gamma-rays from 60Cobalt and cyclophosphamide). We used the method of cDNA arrays to analyze the differential gene expression profiles that were displayed by lymphocytes from radiation-exposed individuals, a human fibroblast cell line, and T lymphocytes from systemic lupus erythematosus (SLE) patients who were treated with cyclophosphamide. A preliminary analysis performed in lymphocytes from three radiation-workers showed that several induced genes can be associated with cell response to ionizing radiation: TRRAP (cell cycle regulation), Ligase IV (DNA repair), MAPK8IP1 and MAPK10 (signal transduction), RASSF2 (apoptosis induction/tumorigenesis), p53 (damage response/maintenance of genetic stability). The in vitro irradiated normal VH16 cell line (primary) showed a complex response to the genotoxic stress at the molecular level. Many apoptotic pathways were concomitantly induced. In addition, several genes involved in signaling and cell cycle arrest/control were significantly modulated after irradiation. Many genes involved in oxidative damage were also induced, indicating that this mechanism seems to be an important component of cell response. After treatment of the SLE patients with cyclophosphamide, 154 genes were differentially and significantly induced. Among them, we identified those associated with drug detoxification, cell cycle control, apoptosis, and tumor-suppressor. These findings indicate that at least two apoptotic pathways were induced after cyclophosphamide treatment. The induction of APAF1 and two genes coding for two subunits of cytochrome c supports a previous report showing increased apoptosis in lymphocytes from SLE patients. The present study provides new information on the molecular mechanism underlying the cell response to genotoxic stress, with relevance to basic and clinical research. [Copyright &y& Elsevier]

The article reports that radiation workers in Great Britain have a lower overall death rate than the general population. A study which looked at cancer incidence and mortality in 174541 people in the National Registry for Radiation Workers epidemiological study found that the workers' risk of developing cancer rises with increasing exposure to ionising radiation. Workers at nuclear power stations and people working with atomic weapons and medical isotopes were included in the study.