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Boretti A. Selectively addressing total risk avoidance for certain chemicals while overlooking others: The case of per-and-poly-fluoroalkyls. Regul Toxicol Pharmacol 2024; 149:105602. [PMID: 38499056 DOI: 10.1016/j.yrtph.2024.105602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 03/04/2024] [Accepted: 03/12/2024] [Indexed: 03/20/2024]
Affiliation(s)
- Alberto Boretti
- Melbourne Institute of Technology, 288 Latrobe Street, Melbourne, 3000, VIC, Australia.
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2
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Iavicoli I, Fontana L, Santocono C, Guarino D, Laudiero M, Calabrese EJ. The challenges of defining hormesis in epidemiological studies: The case of radiation hormesis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 902:166030. [PMID: 37544458 DOI: 10.1016/j.scitotenv.2023.166030] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/24/2023] [Accepted: 08/01/2023] [Indexed: 08/08/2023]
Abstract
In the current radiation protection system, preventive measures and occupational exposure limits for controlling occupational exposure to ionizing radiation are based on the linear no-threshold extrapolation model. However, currently an increasing body of evidence indicates that this paradigm predicts very poorly biological responses in the low-dose exposure region. In addition, several in vitro and in vivo studies demonstrated the presence of hormetic dose response curves correlated to ionizing radiation low exposure. In this regard, it is noteworthy that also the findings of different epidemiological studies, conducted in different categories of occupationally exposed workers (e.g., healthcare, nuclear industrial and aircrew workers), observed lower rates of mortality and/or morbidity from cancer and/or other diseases in exposed workers than in unexposed ones or in the general population, then suggesting the possible occurrence of hormesis. Nevertheless, these results should be considered with caution since the identification of hormetic response in epidemiological studies is rather challenging because of a number of major limitations. In this regard, some of the most remarkable shortcomings found in epidemiological studies performed in workers exposed to ionizing radiation are represented by lack or inadequate definition of exposure doses, use of surrogates of exposure, narrow dose ranges, lack of proper control groups and poor evaluation of confounding factors. Therefore, considering the valuable role and contribution that epidemiological studies might provide to the complex risk assessment and management process, there is a clear and urgent need to overcome the aforementioned limits in order to achieve an adequate, useful and more real-life risk assessment that should also include the key concept of hormesis. Thus, in the present conceptual article we also discuss and provide possible approaches to improve the capacity of epidemiological studies to identify/define the hormetic response and consequently improve the complex process of risk assessment of ionizing radiation at low exposure doses.
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Affiliation(s)
- Ivo Iavicoli
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy.
| | - Luca Fontana
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Carolina Santocono
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Davide Guarino
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Martina Laudiero
- Department of Public Health, Section of Occupational Medicine, University of Naples Federico II, Via S. Pansini 5, 80131 Naples, Italy
| | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA 01003, USA
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3
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Ver Berne J, Politis C, Shaheen E, Jacobs R. Cumulative exposure and lifetime cancer risk from diagnostic radiation in patients undergoing orthognathic surgery: a cross-sectional analysis. Int J Oral Maxillofac Surg 2023; 52:1064-1070. [PMID: 36804279 DOI: 10.1016/j.ijom.2023.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 01/15/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023]
Abstract
Radiation doses in dentomaxillofacial imaging are typically very low. However, diagnostic and follow-up protocols in orthognathic surgery result in a patient-specific risk in effective dose. Estimating the cancer risks from these exposures remains abstract for many maxillofacial surgeons. In this study, 40 orthognathic patients were randomly sampled and their cumulative effective dose (ED) calculated. The lifetime attributable risk of cancer (LAR) was calculated based on the standard radiological protocol for orthognathic surgery follow-up using methods described in the BEIR VII report and RadRAT. The mean cumulative ED of the 40 sampled patients at the end of their 2-year follow-up period was 1.91 ± 0.58 mSv. The LAR at the end of follow-up was 17.65 (90% confidence interval 6.46-32.90) per 100,000 person-years for male orthognathic patients and 13.93 (90% confidence interval 6.27-25.24) per 100,000 person-years for female orthognathic patients. This represents 0.70% and 0.68%, respectively, of the baseline cancer risk for oral, thyroid, and brain cancer combined. Although theoretical, these results provide a framework for interpreting radiation doses and cancer risks in patients undergoing orthognathic surgery. Considering the increased radiation sensitivity in children and adolescents, indication-oriented and patient-specific imaging protocols should be advised.
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Affiliation(s)
- J Ver Berne
- Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Belgium; OMFS-IMPATH Research Group, Department of Imaging and Pathology, Catholic University Leuven, Leuven, Belgium.
| | - C Politis
- Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Belgium; OMFS-IMPATH Research Group, Department of Imaging and Pathology, Catholic University Leuven, Leuven, Belgium
| | - E Shaheen
- Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Belgium; OMFS-IMPATH Research Group, Department of Imaging and Pathology, Catholic University Leuven, Leuven, Belgium
| | - R Jacobs
- Department of Oral and Maxillofacial Surgery, University Hospitals Leuven, Belgium; OMFS-IMPATH Research Group, Department of Imaging and Pathology, Catholic University Leuven, Leuven, Belgium; Department of Dentistry, Karolinska Institutet, Stockholm, Sweden
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4
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Boretti A. There is no reason to persist in the linear no-threshold (LNT) assumption. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2023; 266-267:107239. [PMID: 37393723 DOI: 10.1016/j.jenvrad.2023.107239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/21/2023] [Accepted: 06/27/2023] [Indexed: 07/04/2023]
Affiliation(s)
- Alberto Boretti
- Johnsonville Road, Johnsonville, Wellington, 6037, New Zealand.
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5
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Sahebnasagh A, Eghbali S, Saghafi F, Sureda A, Avan R. Neurohormetic phytochemicals in the pathogenesis of neurodegenerative diseases. Immun Ageing 2022; 19:36. [PMID: 35953850 PMCID: PMC9367062 DOI: 10.1186/s12979-022-00292-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 07/24/2022] [Indexed: 12/02/2022]
Abstract
The world population is progressively ageing, assuming an enormous social and health challenge. As the world ages, neurodegenerative diseases are on the rise. Regarding the progressive nature of these diseases, none of the neurodegenerative diseases are curable at date, and the existing treatments can only help relieve the symptoms or slow the progression. Recently, hormesis has increased attention in the treatment of age-related neurodegenerative diseases. The concept of hormesis refers to a biphasic dose-response phenomenon, where low levels of the drug or stress exert protective of beneficial effects and high doses deleterious or toxic effects. Neurohormesis, as the adaptive aspect of hormetic dose responses in neurons, has been shown to slow the onset of neurodegenerative diseases and reduce the damages caused by aging, stroke, and traumatic brain injury. Hormesis was also observed to modulate anxiety, stress, pain, and the severity of seizure. Thus, neurohormesis can be considered as a potentially innovative approach in the treatment of neurodegenerative and other neurologic disorders. Herbal medicinal products and supplements are often considered health resources with many applications. The hormesis phenomenon in medicinal plants is valuable and several studies have shown that hormetic mechanisms of bioactive compounds can prevent or ameliorate the neurodegenerative pathogenesis in animal models of Alzheimer’s and Parkinson’s diseases. Moreover, the hormesis activity of phytochemicals has been evaluated in other neurological disorders such as Autism and Huntington’s disease. In this review, the neurohormetic dose–response concept and the possible underlying neuroprotection mechanisms are discussed. Different neurohormetic phytochemicals used for the better management of neurodegenerative diseases, the rationale for using them, and the key findings of their studies are also reviewed.
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Sun T, Zhan J, Li F, Ji C, Wu H. Effect of microplastics on aquatic biota: A hormetic perspective. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 285:117206. [PMID: 33971425 DOI: 10.1016/j.envpol.2021.117206] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 04/06/2021] [Accepted: 04/16/2021] [Indexed: 05/17/2023]
Abstract
As emerging pollutants, microplastics (MPs) have been found globally in various freshwater and marine matrices. This study recompiled 270 endpoints of 3765 individuals from 43 publications, reporting the onset of enhanced biological performance and reduced oxidative stress biomarkers induced by MPs in aquatic organisms at environmentally relevant concentrations (≤1 mg/L, median = 0.1 mg/L). The stimulatory responses of consumption, growth, reproduction and survival ranged from 131% to 144% of the control, with a combined response of 136%. The overall inhibitory response of 9 oxidative stress biomarkers was 71% of the control, and commonly below 75%. The random-effects meta-regression indicated that the extents of MPs-induced responses were independent of habitat, MP composition, morphology, particle size and exposure duration. The results implied that the exposure to MPs at low and high concentrations might induce opposite/non-monotonic responses in aquatic biota. Correspondingly, the hormetic dose response relationships were found at various endpoints, such as reproduction, genotoxicity, immunotoxicity, neurotoxicity and behavioral alteration. Hormesis offers a novel perspective for understanding the dose response mode of aquatic organisms exposed to low and high concentrations of MPs, highlighting the necessity to incorporate the hormetic dose response model into the ecological/environmental risk assessment of MPs.
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Affiliation(s)
- Tao Sun
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, 264003, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Junfei Zhan
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, 264003, PR China; University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Fei Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, 264003, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences (CAS), Qingdao, 266071, PR China
| | - Chenglong Ji
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, 264003, PR China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences (CAS), Qingdao, 266071, PR China
| | - Huifeng Wu
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, 264003, PR China; Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences (CAS), Qingdao, 266071, PR China.
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Oakley PA, Betz JW, Harrison DE, Siskin LA, Hirsh DW. Radiophobia Overreaction: College of Chiropractors of British Columbia Revoke Full X-Ray Rights Based on Flawed Study and Radiation Fear-Mongering. Dose Response 2021; 19:15593258211033142. [PMID: 34421439 PMCID: PMC8375354 DOI: 10.1177/15593258211033142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 06/17/2021] [Accepted: 06/22/2021] [Indexed: 01/11/2023] Open
Abstract
Fears over radiation have created irrational pressures to dissuade radiography use within chiropractic. Recently, the regulatory body for chiropractors practicing in British Columbia, Canada, the College of Chiropractors of British Columbia (CCBC), contracted Pierre Côté to review the clinical use of X-rays within the chiropractic profession. A "rapid review" was performed and published quickly and included only 9 papers, the most recent dating from 2005; they concluded, "Given the inherent risks of radiation, we recommend that chiropractors do not use radiographs for the routine and repeat evaluation of the structure and function of the spine." The CCBC then launched an immediate review of the use of X-rays by chiropractors in their jurisdiction. Member and public opinion were gathered but not presented to their members. On February 4, 2021, the College announced amendments to their Professional Conduct Handbook that revoked X-ray rights for routine/repeat assessment and management of patients with spine disorders. Here, we highlight current and historical evidence that substantiates that X-rays are not a public health threat. We also point out critical and insurmountable flaws in the single paper used to support irrational and unscientific policy that discriminates against chiropractors who practice certain forms of evidence-based X-ray-guided methods.
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Affiliation(s)
| | | | | | | | | | - International Chiropractors Association Rapid Response Research Review Subcommittee
- Private Practice, Newmarket, ON, Canada
- Private Practice, Boise, ID, USA
- CBP NonProfit, Inc, Eagle, ID, USA
- Private Practice, Green Brook, NJ, USA
- Private Practice, Laurel, MD, USA
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Cwikel J, Sheiner E, Sergienko R, Slusky D, Quastel M. Hospitalizations Among Chernobyl-Exposed Immigrants to the Negev of Israel, 1992-2017: A Historical Follow-Up Study. J Immigr Minor Health 2021; 24:469-480. [PMID: 33974176 DOI: 10.1007/s10903-021-01202-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/18/2021] [Indexed: 11/26/2022]
Abstract
On April 26th, 1986 the nuclear reactor at Chernobyl, Ukraine exploded, causing the worst radiation disaster in history. The aim was to estimate hospitalization rates among exposed civilians who later immigrated to Israel. We conducted a historical follow-up study, among persons exposed to Chernobyl (n = 1128) using linked hospitalization records from Soroka University Medical Center (SUMC), compared with immigrants from other areas of the Former Soviet Union (FSU) (n = 11,574), immigrants not from FSU (n = 11,742) and native-born Israelis (n = 8351), matched on age and gender (N = 32,795). Hospitalizations for specific ICD-10 coded diagnostic groups were analyzed by exposure and comparison groups by gender and age at accident. In addition, the rate of hospitalization, and the duration of hospital days and the number of hospitalizations for these selected diagnostic groups was also calculated. Hospitalizations for specific ICD-10 coded diagnostic groups and for any hospitalization in these diagnostic groups in general were analyzed by exposure and comparison groups and by covariates (gender and age at accident). The rate of any hospitalization for the selected diagnostic groups was elevated in the low exposure Chernobyl group (51.1%), which was significantly higher than the immigrant (41.6%) and the Israel-born comparison group (35.1%) (p < .01) but did not differ from either the high exposure group (46.9%) or the FSU comparison group (46.4%), according to the post-hoc tests. The total number of hospitalizations in the low exposure Chernobyl group (2.35) differed from the immigrant (1.73) and Israel comparison group (1.26) (p < .01) but did not differ from the FSU comparison group (1.73) or the high exposure group (2.10). Low exposure women showed higher rates of circulatory hospitalizations (33.8%) compared to immigrants (22.8%) and Israeli born (16.5%), while high exposure women (27.5%) only differed from Israelis (p < .01). Neither exposure group differed from FSU immigrant women on the rate of circulatory hospitalizations. Post-hoc tests showed that among women in the low exposure group, there was a significant difference in rate of hospitalizations for neoplasms (28.6%) compared to the three comparison groups; FSU (18.6%), immigrants (15.7%) and Israel (13.1) (p < .01). Those among the low exposure group who were over the age of 20 at the time of the accident showed the higher rates of circulatory (51.2%) and neoplasm hospitalizations (33.3%), compared to the other immigrant groups (p < .01). When controlling for both age at accident and gender, hospitalizations for neoplasms were higher among Chernobyl-exposed populations (RR = 1.65, RR = 1.77 for high and low-exposure groups, respectively) compared to other FSU immigrants (RR = 1.31) other immigrants (RR = 1.11) and Israeli born (RR = 1.0) after controlling for gender and age at accident. High RRs attributable to Chernobyl exposure were also found for circulatory diseases compared to other immigrants and Israeli born (RRs = 1.50, 1.47 for high and low exposure compared to 1.11. and 1.0, other immigrants and Israeli born, respectively). Endocrine problems and disorders of the eye also showed elevated RR compared to the immigrant comparison groups. Respiratory and mental disorders did not show any consistent association with Chernobyl exposure. The findings support unique Chernobyl morbidity associations only in some diagnostic groups, particularly for low exposure women. General immigration effects on hospitalizations compared to the Israeli born population were found on all diagnostic groups. There is a need to improve the services and medical follow-up for these Chernobyl exposed groups in specific diagnostic groups.
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Affiliation(s)
- Julie Cwikel
- Chilewich Family Chair in Studies in Social Integration, Spitzer Department of Social Work, & BGU Center for Women's Health Studies and Promotion, POB 653, 84105, Beer Sheva, Israel.
| | - Eyal Sheiner
- OB-GYN (Women's B Ward), Soroka University Medical Center, Beer Sheva, Israel
| | - Ruslan Sergienko
- Department of Epidemiology, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel
| | | | - Michael Quastel
- Nuclear Medicine, Soroka University Medical Center (retired), Beer Sheva, Israel
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Oakley PA, Harrison DE. Radiophobic Fear-Mongering, Misappropriation of Medical References and Dismissing Relevant Data Forms the False Stance for Advocating Against the Use of Routine and Repeat Radiography in Chiropractic and Manual Therapy. Dose Response 2021; 19:1559325820984626. [PMID: 33628151 PMCID: PMC7883173 DOI: 10.1177/1559325820984626] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 12/04/2020] [Accepted: 12/05/2020] [Indexed: 12/14/2022] Open
Abstract
There is a faction within the chiropractic profession passionately advocating against the routine use of X-rays in the diagnosis, treatment and management of patients with spinal disorders (aka subluxation). These activists reiterate common false statements such as "there is no evidence" for biomechanical spine assessment by X-ray, "there are no guidelines" supporting routine imaging, and also promulgate the reiterating narrative that "X-rays are dangerous." These arguments come in the form of recycled allopathic "red flag only" medical guidelines for spine care, opinion pieces and consensus statements. Herein, we review these common arguments and present compelling data refuting such claims. It quickly becomes evident that these statements are false. They are based on cherry-picked medical references and, most importantly, expansive evidence against this narrative continues to be ignored. Factually, there is considerable evidential support for routine use of radiological imaging in chiropractic and manual therapies for 3 main purposes: 1. To assess spinopelvic biomechanical parameters; 2. To screen for relative and absolute contraindications; 3. To reassess a patient's progress from some forms of spine altering treatments. Finally, and most importantly, we summarize why the long-held notion of carcinogenicity from X-rays is not a valid argument.
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Oakley PA, Harrison DE. Are Continued Efforts to Reduce Radiation Exposures from X-Rays Warranted? Dose Response 2021; 19:1559325821995653. [PMID: 33746654 PMCID: PMC7903835 DOI: 10.1177/1559325821995653] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/23/2021] [Accepted: 01/23/2021] [Indexed: 12/12/2022] Open
Abstract
There are pressures to avoid use of radiological imaging throughout all healthcare due to the notion that all radiation is carcinogenic. This perception stems from the long-standing use of the linear no-threshold (LNT) assumption of risk associated with radiation exposures. This societal perception has led to relentless efforts to avoid and reduce radiation exposures to patients at great costs. Many radiation reduction campaigns have been launched to dissuade doctors from using radiation imaging. Lower-dose imaging techniques and practices are being advocated. Alternate imaging procedures are encouraged. Are these efforts warranted? Based on recent evidence, LNT ideology is shown to be defunct for risk assessment at low-dose exposure ranges which includes X-rays and CT scans. In fact, the best evidence that was once used to support LNT ideology, including the Life Span Study data, now indicates thresholds for cancer induction are high; therefore, low-dose X-rays cannot cause harm. Current practices are safe as exposures currently encountered are orders of magnitude below threshold levels shown to be harmful. As long as imaging is medically warranted, it is shown that efforts to reduce exposures that are within background radiation levels and that are also shown to enhance health by upregulating natural adaptive protection systems are definitively wasted resources.
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Henry E, Arcangeli ML. How Hematopoietic Stem Cells Respond to Irradiation: Similarities and Differences between Low and High Doses of Ionizing Radiations. Exp Hematol 2020; 94:11-19. [PMID: 33290858 DOI: 10.1016/j.exphem.2020.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/12/2020] [Accepted: 12/01/2020] [Indexed: 12/12/2022]
Abstract
In this review, we will specifically address the newest insights on the effect of low doses of ionizing radiations on the hematopoietic stem cells, which are prone to long-term deleterious effects. Impact of high doses of irradiation on hematopoietic cells has been widely studied over the years, in line with the risk of accidental or terrorist exposure to irradiation and with a particular attention to the sensitivity of the hematopoietic system. Recently, more studies have focused on lower doses of irradiation on different tissues, due to the increasing exposure caused by medical imaging, radiotherapy or plane travelling for instance. Hence, we will delineate similarities and discrepancies in HSC response to high and low doses of irradiation from these studies.
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Affiliation(s)
- Elia Henry
- Team Niche and Cancer in Hematopoiesis, U1274, INSERM, 92260 Fontenay-aux-Roses, France; Laboratory of Hematopoietic Stem Cells and Leukemia/Service Stem Cells and Radiation/iRCM/JACOB/DRF, CEA, Fontenay-aux-Roses, France; UMR Stabilité Génétique Cellules Souches et Radiations, Université de Paris, CEA, Fontenay-aux-Roses, France; UMR Stabilité Génétique Cellules Souches et Radiations, Université Paris-Saclay, CEA, Fontenay-aux-Roses, France
| | - Marie-Laure Arcangeli
- Team Niche and Cancer in Hematopoiesis, U1274, INSERM, 92260 Fontenay-aux-Roses, France; Laboratory of Hematopoietic Stem Cells and Leukemia/Service Stem Cells and Radiation/iRCM/JACOB/DRF, CEA, Fontenay-aux-Roses, France; UMR Stabilité Génétique Cellules Souches et Radiations, Université de Paris, CEA, Fontenay-aux-Roses, France; UMR Stabilité Génétique Cellules Souches et Radiations, Université Paris-Saclay, CEA, Fontenay-aux-Roses, France.
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12
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Agathokleous E, Calabrese EJ. Environmental toxicology and ecotoxicology: How clean is clean? Rethinking dose-response analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 746:138769. [PMID: 32389333 DOI: 10.1016/j.scitotenv.2020.138769] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/15/2020] [Accepted: 04/15/2020] [Indexed: 05/17/2023]
Abstract
Global agendas for sustaining clean environments target remediation of multimedia contaminants, but how clean is clean? Environmental Toxicology and Ecotoxicology focus on issues concerning "clean". However, the models used to assess the effects of environmental multimedia on individual living organisms and communities or populations in Environmental Toxicology and Ecotoxicology may fail to provide reliable estimates for risk assessment and optimize health. Recent developments in low-dose effects research provide a novel means in Environmental Toxicology and Ecotoxicology to improve the quality of hazard and risk assessment.
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Affiliation(s)
- Evgenios Agathokleous
- Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science and Technology (NUIST), Ningliu Rd. 219, Nanjing, Jiangsu 210044, China.
| | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA 01003, USA
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Agathokleous E, Barceló D, Tsatsakis A, Calabrese EJ. Hydrocarbon-induced hormesis: 101 years of evidence at the margin? ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 265:114846. [PMID: 32474358 DOI: 10.1016/j.envpol.2020.114846] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 05/12/2020] [Accepted: 05/18/2020] [Indexed: 06/11/2023]
Abstract
Hydrocarbons are used worldwide for an array of purposes ranging from transportation to making plastics and synthetic fibers. Hydrocarbons pollution can occur from local to global scales, becoming a focus of regulatory authorities since a long time ago. While studies show numerous adverse effects on biota, such effects usually occur at very high doses. This paper collates significant evidence showing that hydrocarbons induce hormesis in biota, with dual effects of low versus high doses. Hydrocarbon-induced hormetic responses should be considered in relevant dose-response studies as well as in risk assessment. Dismissing hormesis could lead to incorrect predictions of hydrocarbons effects, which can occur at doses up to 100 times smaller than the traditional toxicological threshold, and would raise serious concerns regarding human and ecological health safety.
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Affiliation(s)
- Evgenios Agathokleous
- Key Laboratory of Agrometeorology of Jiangsu Province, Institute of Ecology, School of Applied Meteorology, Nanjing University of Information Science and Technology (NUIST), Ningliu Rd. 219, Nanjing, Jiangsu, 210044, China.
| | - Damià Barceló
- Institute of Environmental Assessment and Water Research, IDAEA-CSIC, C/ Jordi Girona 18-26, 08034, Barcelona, Spain; Catalan Institute for Water Research, ICRA, Emili Grahit 101, 17003, Girona, Spain
| | | | - Edward J Calabrese
- Department of Environmental Health Sciences, Morrill I, N344, University of Massachusetts, Amherst, MA, 01003, USA
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14
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Oakley PA, Navid Ehsani N, Harrison DE. 5 Reasons Why Scoliosis X-Rays Are Not Harmful. Dose Response 2020; 18:1559325820957797. [PMID: 32963506 PMCID: PMC7488912 DOI: 10.1177/1559325820957797] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Revised: 08/13/2020] [Accepted: 08/17/2020] [Indexed: 12/12/2022] Open
Abstract
Radiographic imaging for scoliosis screening, diagnosis, treatment, and management is the gold standard assessment tool. Scoliosis patients receive many repeat radiographs, typically 10-25 and as many as 40-50, equating to a maximum 50 mGy of cumulative exposure. It is argued this amount of radiation exposure is not carcinogenic to scoliosis patients for 5 main reasons: 1. Estimated theoretical cumulative effective doses remain below the carcinogenic dose threshold; 2. Scoliosis patient x-rays are delivered in serial exposures and therefore, mitigate any potential cumulative effect; 3. Linear no-threshold cancer risk estimates from scoliosis patient cohorts are flawed due to faulty science; 4. Standardized incidence/mortality ratios demonstrating increased cancers from aged scoliosis cohorts are confounded by the effects of the disease entity itself making it impossible to claim cause and effect resulting from low-dose radiation exposures from spinal imaging; 5. Children are not more susceptible to radiation damage than adults. Radiophobia concerns from patients, parents, and doctors over repeat imaging for scoliosis treatment and management is not justified; it adds unnecessary anxiety to the patient (and their parents) and interferes with optimal medical management. X-rays taken in the evidence-based management of scoliosis should be taken without hesitation or concern about negligible radiation exposures.
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15
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Oakley PA, Harrison DE. X-Ray Hesitancy: Patients' Radiophobic Concerns Over Medical X-rays. Dose Response 2020; 18:1559325820959542. [PMID: 32994755 PMCID: PMC7503016 DOI: 10.1177/1559325820959542] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/20/2020] [Accepted: 08/25/2020] [Indexed: 12/14/2022] Open
Abstract
All too often the family physician, orthopedic surgeon, dentist or chiropractor is met with radiophobic concerns about X-ray imaging in the clinical setting. These concerns, however, are unwarranted fears based on common but ill-informed and perpetuated ideology versus current understanding of the effects of low-dose radiation exposures. Themes of X-ray hesitancy come in 3 forms: 1. All radiation exposures are harmful (i.e. carcinogenic); 2. Radiation exposures are cumulative; 3. Children are more susceptible to radiation. Herein we address these concerns and find that low-dose radiation activates the body's adaptive responses and leads to reduced cancers. Low-dose radiation is not cumulative as long as enough time (e.g. 24 hrs) passes prior to a repeated exposure, and any damage is repaired, removed, or eliminated. Children have more active immune systems; the literature shows children are no more affected than adults by radiation exposures. Medical X-rays present a small, insignificant addition to background radiation exposure that is not likely to cause harm. Doctors and patients alike should be better informed of the lack of risks from diagnostic radiation and the decision to image should rely on the best evidence, unique needs of the patient, and the expertise of the physician-not radiophobia.
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16
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Oakley PA, Harrison DE. Are Restrictive Medical Radiation Imaging Campaigns Misguided? It Seems So: A Case Example of the American Chiropractic Association's Adoption of "Choosing Wisely". Dose Response 2020; 18:1559325820919321. [PMID: 32425722 PMCID: PMC7218311 DOI: 10.1177/1559325820919321] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 03/12/2020] [Accepted: 03/20/2020] [Indexed: 12/18/2022] Open
Abstract
Since the 1980s, increased utilization of medical radiology, primarily computed tomography, has doubled medically sourced radiation exposures. Ensuing fear-mongering media headlines of iatrogenic cancers from these essential medical diagnostic tools has led the public and medical professionals alike to display escalating radiophobia. Problematically, several campaigns including Image Gently, Image Wisely, and facets of Choosing Wisely propagate fears of all medical radiation, which is necessary for the delivery of effective and efficient health care. Since there are no sound data supporting the alleged risks from low-dose radiation and since there is abundant evidence of health benefits from low-doses, these imaging campaigns seem misguided. Further, thresholds for cancer are 100 to 1000-fold greater than X-rays, which are within the realm of natural background radiation where no harm has ever been validated. Here, we focus on radiographic imaging for use in spinal rehabilitation by manual therapists, chiropractors, and physiotherapists as spinal X-rays represent the lowest levels of radiation imaging and are critical in the diagnosis and management of spine-related disorders. Using a case example of a chiropractic association adopting "Choosing Wisely," we argue that these campaigns only fuel the pervasive radiophobia and continue to constrain medical professionals, attempting to deliver quality care to patients.
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Oakley PA, Harrison DE. Death of the ALARA Radiation Protection Principle as Used in the Medical Sector. Dose Response 2020; 18:1559325820921641. [PMID: 32425724 PMCID: PMC7218317 DOI: 10.1177/1559325820921641] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2020] [Revised: 03/31/2020] [Accepted: 04/03/2020] [Indexed: 12/17/2022] Open
Abstract
ALARA is the acronym for "As Low As Reasonably Achievable." It is a radiation protection concept borne from the linear no-threshold (LNT) hypothesis. There are no valid data today supporting the use of LNT in the low-dose range, so dose as a surrogate for risk in radiological imaging is not appropriate, and therefore, the use of the ALARA concept is obsolete. Continued use of an outdated and erroneous principle unnecessarily constrains medical professionals attempting to deliver high-quality care to patients by leading to a reluctance by doctors to order images, a resistance from patients/parents to receive images, subquality images, repeated imaging, increased radiation exposures, the stifling of low-dose radiation research and treatment, and the propagation of radiophobia and continued endorsement of ALARA by regulatory bodies. All these factors result from the fear of radiogenic cancer, many years in the future, that will not occur. It has been established that the dose threshold for leukemia is higher than previously thought. A low-dose radiation exposure from medical imaging will likely upregulate the body's adaptive protection systems leading to the prevention of future cancers. The ALARA principle, as used as a radiation protection principle throughout medicine, is scientifically defunct and should be abandoned.
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18
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Joo HM, Hong EH, Cho SJ, Nam SY, Kim JY. Preventative and Therapeutic Effects of Low-dose Ionizing Radiation on the Allergic Response of Rat Basophilic Leukemia Cells. Sci Rep 2019; 9:16079. [PMID: 31695078 PMCID: PMC6834612 DOI: 10.1038/s41598-019-52399-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 10/07/2019] [Indexed: 12/12/2022] Open
Abstract
The prevalence of allergies has increased over the last four decades. In allergic reactions, mast cells induce a hypersensitive immune response to a substance that is normally harmless. Ionizing radiation has different biological effects depending on the dose and dose rate. In this study, we investigated whether low-dose irradiation before (preventative effect) or after (therapeutic effect) an antigen-antibody reaction has an anti-allergic effect. To test this, we activated rat basophilic leukemia (RBL-2H3) mast cells with anti-2,4-dinitrophenyl IgE (antibody) and 2,4-dinitrophenyl human serum albumin, which served as an antigen. To test for both the potential of a preventative effect and a therapeutic effect, we irradiated mast cells both before and after mast cell activation, and we measured mediator release and signaling pathway activity. Low-dose ionizing radiation suppressed mediator release from RBL-2H3 mast cells activated by the antigen-antibody reaction regardless of when the mast cells were irradiated. These results were due to the suppression of FcεRI expression. Therefore, we suggest that low-dose ionizing radiation has a preventative and therapeutic effect in allergic reactions via the FcεRI-mediated RBL-2H3 mast cell activation system.
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Affiliation(s)
- Hae Mi Joo
- Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd, Seoul, 132-703, Republic of Korea
| | - Eun Hee Hong
- Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd, Seoul, 132-703, Republic of Korea
| | - Seong-Jun Cho
- Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd, Seoul, 132-703, Republic of Korea
| | - Seon Young Nam
- Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd, Seoul, 132-703, Republic of Korea
| | - Ji Young Kim
- Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd, Seoul, 132-703, Republic of Korea.
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19
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Relevance of Non-Targeted Effects for Radiotherapy and Diagnostic Radiology; A Historical and Conceptual Analysis of Key Players. Cancers (Basel) 2019; 11:cancers11091236. [PMID: 31450803 PMCID: PMC6770832 DOI: 10.3390/cancers11091236] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/16/2019] [Accepted: 08/18/2019] [Indexed: 11/17/2022] Open
Abstract
Non-targeted effects (NTE) such as bystander effects or genomic instability have been known for many years but their significance for radiotherapy or medical diagnostic radiology are far from clear. Central to the issue are reported differences in the response of normal and tumour tissues to signals from directly irradiated cells. This review will discuss possible mechanisms and implications of these different responses and will then discuss possible new therapeutic avenues suggested by the analysis. Finally, the importance of NTE for diagnostic radiology and nuclear medicine which stems from the dominance of NTE in the low-dose region of the dose–response curve will be presented. Areas such as second cancer induction and microenvironment plasticity will be discussed.
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20
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Abstract
The hormesis concept demonstrates that in contrast to the toxic effect of high doses of materials, irradiation, etc., low doses of them are beneficial and, in addition, help to eliminate (prevent) the deleterious effect of high doses given after it. By this effect, it is an important factor of (human) evolution protecting man from harmful impacts, similarly to the role of immunity. However, immunity is also continuously influenced by hormetic effects of environmental [chemical (pollutions), physical (background irradiations and heat), etc.] and medical (drugs and therapeutic irradiations) and food interactions. In contrast to earlier beliefs, the no-threshold irradiation dogma is not valid in low-dose domains and here the hormesis concept is valid. Low-dose therapeutic irradiation, as well as background irradiations (by radon spas or moderately far from the epicenter of atomic bomb or nuclear facilities), is rather beneficial than destructive and the fear from them seems to be unreasonable from immunological point of view. Practically, all immune parameters are beneficially influenced by all forms of low-dose radiations.
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Affiliation(s)
- György Csaba
- 1 Department of Genetics, Cell- and Immunobiology, Semmelweis University, Budapest, Hungary
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21
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Doss M. Comment on 'Implications of recent epidemiologic studies for the linear nonthreshold model and radiation protection'. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2019; 39:650-654. [PMID: 31125319 DOI: 10.1088/1361-6498/ab076a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Affiliation(s)
- Mohan Doss
- Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA, 19111 United States of America
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22
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Pennington CW, Siegel JA. The Linear No-Threshold Model of Low-Dose Radiogenic Cancer: A Failed Fiction. Dose Response 2019; 17:1559325818824200. [PMID: 30792613 PMCID: PMC6376521 DOI: 10.1177/1559325818824200] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 11/06/2018] [Accepted: 12/18/2018] [Indexed: 12/17/2022] Open
Abstract
The linear no-threshold (LNT) model for low-dose, radiogenic cancer has been a fixture of radiation protection and regulatory requirements for decades, but its validity has long been contested. This article finds, yet again, more questionable data and analyses purporting to support the model, this within the “gold-standard” data set for estimating radiation effects in humans. Herein is addressed a number of significant uncertainties in the Radiation Effects Research Foundation’s Life Span Study (LSS) cohort of atomic bomb survivors, especially in its latest update of 2017, showing that the study’s support of the LNT model is not evidence based. We find that its latest 2 analyses of solid cancer incidence ignore biology and do not support the LNT model. Additionally, we identify data inconsistencies and missing causalities in the LSS data and analyses that place reliance on uncertain, imputed data and apparently flawed modeling, further invalidating the LNT model. These observations lead to a most credible conclusion, one supporting a threshold model for the dose–response relationship between low-dose radiation exposure and radiogenic cancer in humans. Based upon these findings and those cited from others, it becomes apparent that the LNT model cannot be scientifically valid.
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23
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Trajkova K, Dilevska I, Petkovska R, Trajkov D, Kroneis T, Schwinger W, Sorantin E. The influence of the iodinate contrast medium during CT: Single center experience - Development of two competitive in-house methods for automated quantification of DDSB. MAKEDONSKO FARMACEVTSKI BILTEN 2019. [DOI: 10.33320/maced.pharm.bull.2019.65.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
DNA damage induced by ionizing radiation may ultimately lead to cell death or initiate cancer cells development. Today it is difficult to estimate what the actual damage to the human body will be, given the fact that today in the world the number of diagnostic procedures using radiation and iodine contrast media is increasing, and the existence of a number of factors that can affect the radiation dose in vivo. At the same time, development of new methods is required, which can determine in a much shorter time what will be the effect of diagnostic radiation on the DNA molecule. For these purposes we develop two competitive inhouse methods for automated quantification of DNA double strand brakes (DDSB) in peripheral blood lymphocytes: immunofluorescence determining of γH2AX with stained microscopic slides and determining the occurrence of DDSB with the flow cytometry. Our initial results shown that computed tomography (CT) can cause damage in the DNA molecule in the form of DDSB, the existence of linear dependence with the increase in low and high range of CTDI and the number of γH2AX, and that iodine contrast media can increase the occurrence of DNA double strand brakes.
Keywords: CT examinations, ICM, immunofluorescence, flow cytometry, DDSB
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Affiliation(s)
- Klimentina Trajkova
- Division of Pediatric Radiology, Department of Radiology, Medical University Graz, Auenbruggerplatz 34 A – 8036, 8010 Graz, Austria
| | - Ivana Dilevska
- Division of Pediatric Radiology, Department of Radiology, Medical University Graz, Auenbruggerplatz 34 A – 8036, 8010 Graz, Austria
| | - Rumenka Petkovska
- Institute of Applied Chemistry and Pharmaceutical Analysis, Faculty of Pharmacy, Ss. Cyril and Methodius University, Majka Tereza 47, 1000 Skopje, Republic of North Macedonia
| | - Dejan Trajkov
- Division of Pediatric Radiology, Department of Radiology, Medical University Graz, Auenbruggerplatz 34 A – 8036, 8010 Graz, Austria
| | - Thomas Kroneis
- Division of Cell Biology, Histology and Embryology, Gottfried Schatz Research Center, Medical University Graz, Neue Stiftingtalstraße 6, 8010 Graz, Austria
| | - Wolfgang Schwinger
- Division of pediatric hematology/oncology, Department of Paediatrics and Adolescent Medicine, Medical University Graz, Auenbruggerplatz 34/2 – 8036, 8010 Graz, Austria
| | - Erich Sorantin
- Division of Pediatric Radiology, Department of Radiology, Medical University Graz, Auenbruggerplatz 34 A – 8036, 8010 Graz, Austria
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24
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Doss M. Commentary No. 27 — Implications of Recent Epidemiologic Studies for the Linear‐Nonthreshold Model and Radiation Protection (2018). Med Phys 2018. [DOI: 10.1002/mp.13304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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25
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Ulsh BA. A critical evaluation of the NCRP COMMENTARY 27 endorsement of the linear no-threshold model of radiation effects. ENVIRONMENTAL RESEARCH 2018; 167:472-487. [PMID: 30138826 DOI: 10.1016/j.envres.2018.08.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 07/31/2018] [Accepted: 08/03/2018] [Indexed: 06/08/2023]
Abstract
Regulatory policy to protect the public and the environment from radiation is universally based on the linear, no-threshold model (LNT) of radiation effects. This model has been controversial since its inception over nine decades ago, and remains so to this day, but it has proved remarkably resistant to challenge from the scientific community. The LNT model has been repeatedly endorsed by expert advisory bodies, and regulatory agencies in turn adopt policies that reflect this advice. Unfortunately, these endorsements rest on a foundation of institutional inertia and numerous logical fallacies. These include most significantly setting the LNT as the null hypothesis, and shifting the burden of proof onto LNT skeptics. Other examples include arbitrary exclusion of alternative hypotheses, ignoring criticisms of the LNT, cherry-picking evidence, and making policy judgements without foundation. This paper presents an evaluation of the National Council on Radiation Protection and Measurements' (NCRP) Commentary 27, which concluded that recent epidemiological studies are compatible with the continued use of the LNT model for radiation protection. While this report will likely provide political cover for regulators' continued reliance on the LNT, it is a missed opportunity to advance the scientific discussion of the effects of low dose, low dose-rate radiation exposure. Due to its Congressionally chartered mission, no organization is better positioned than the NCRP to move this debate forward, and recommendations for doing so in future reviews are provided.
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Affiliation(s)
- Brant A Ulsh
- M. H. Chew & Associates, 7633 Southfront Rd, Ste. 170, Livermore, CA 94551-8211, United States.
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26
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Park G, Son B, Kang J, Lee S, Jeon J, Kim JH, Yi GR, Youn H, Moon C, Nam SY, Youn B. LDR-Induced miR-30a and miR-30b Target the PAI-1 Pathway to Control Adverse Effects of NSCLC Radiotherapy. Mol Ther 2018; 27:342-354. [PMID: 30424954 DOI: 10.1016/j.ymthe.2018.10.015] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 10/18/2018] [Accepted: 10/19/2018] [Indexed: 12/24/2022] Open
Abstract
Radiotherapy has been a central part in curing non-small cell lung cancer (NSCLC). However, it is possible that not all of the tumor cells are destroyed by radiation; therefore, it is important to effectively control residual tumor cells that could become aggressive and resistant to radiotherapy. In this study, we aimed to investigate the molecular mechanism of decreased NSCLC radioresistance by low-dose radiation (LDR) pretreatment. The results indicated that miR-30a and miR-30b, which effectively inhibited plasminogen activator inhibitor-1 (PAI-1), were overexpressed by treatment of LDR to NSCLC cells. Phosphorylation of Akt and ERK, the downstream survival signals of PAI-1, was decreased by PAI-1 inhibition. Reduced cell survival and epithelial-mesenchymal transition by PAI-1 inhibition were confirmed in NSCLC cells. Moreover, in vivo orthotopic xenograft mouse models with 7C1 nanoparticles to deliver miRNAs showed that tumor growth and aggressiveness were efficiently decreased by LDR treatment followed by radiotherapy. Taken together, the present study suggested that PAI-1, whose expression is regulated by LDR, was critical for controlling surviving tumor cells after radiotherapy.
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Affiliation(s)
- Gaeul Park
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Republic of Korea
| | - Beomseok Son
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Republic of Korea
| | - JiHoon Kang
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Republic of Korea; Laboratory of Radiation Exposure & Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological & Medical Sciences, Seoul 01812, Republic of Korea
| | - Sungmin Lee
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Republic of Korea
| | - Jaewan Jeon
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Republic of Korea; Department of Radiation Oncology, Haeundae Paik Hospital, Inje University School of Medicine, Busan 48108, Republic of Korea
| | - Joo-Hyung Kim
- Department of Chemistry, Molecular Design Institute, New York University, New York, NY 10003, USA
| | - Gi-Ra Yi
- School of Chemical Engineering, Sungkyunkwan University (SKKU), Suwon 16419, Republic of Korea
| | - HyeSook Youn
- Department of Integrative Bioscience and Biotechnology, Sejong University, Seoul 05006, Republic of Korea
| | - Changjong Moon
- Department of Veterinary Anatomy, College of Veterinary Medicine and BK21 Plus Project Team, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Seon Young Nam
- Low-Dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul 01450, Republic of Korea
| | - BuHyun Youn
- Department of Integrated Biological Science, Pusan National University, Busan 46241, Republic of Korea; Department of Biological Sciences, Pusan National University, Busan 46241, Republic of Korea.
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27
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Mercuri M, Baigrie B, Upshur REG. Going from evidence to recommendations: Can GRADE get us there? J Eval Clin Pract 2018; 24:1232-1239. [PMID: 29314554 DOI: 10.1111/jep.12857] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 11/06/2017] [Indexed: 01/13/2023]
Abstract
The evidence based medicine movement has championed the need for objective and transparent methods of clinical guideline development. The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) framework was developed for that purpose. Central to this framework is criteria for assessing the quality of evidence from clinical studies and the impact that body of evidence should have on our confidence in the clinical effectiveness of a therapy under examination. Grades of Recommendation, Assessment, Development, and Evaluation has been adopted by a number of professional medical societies and organizations as a means for orienting the development of clinical guidelines. As a result, the method of GRADE has implications on how health care is delivered and patient outcomes. In this paper, we reveal several issues with the underlying logic of GRADE that warrant further discussion. First, the definitions of the "grades of evidence" provided by GRADE, while explicit, are functionally vague. Second, the "criteria for assigning grade of evidence" is seemingly arbitrary and arguably logically incoherent. Finally, the GRADE method is unclear on how to integrate evidence grades with other important factors, such as patient preferences, and trade-offs between costs, benefits, and harms when proposing a clinical practice recommendation. Much of the GRADE method requires judgement on the part of the user, making it unclear as to how the framework reduces bias in recommendations or makes them more transparent-both goals of the programme. It is our view that the issues presented in this paper undermine GRADE's justificatory scheme, thereby limiting the usefulness of GRADE as a tool for developing clinical recommendations.
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Affiliation(s)
- Mathew Mercuri
- Department of Medicine, Division of Emergency Medicine, McMaster University, Hamilton, Canada.,Institute for the History and Philosophy of Science and Technology, University of Toronto, Toronto, Canada.,African Centre for Epistemology and Philosophy of Science, University of Johannesburg, Auckland Park, South Africa
| | - Brian Baigrie
- Institute for the History and Philosophy of Science and Technology, University of Toronto, Toronto, Canada
| | - Ross E G Upshur
- Dalla Lana School for Public Health, University of Toronto, Toronto, Canada
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28
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Jangiam W, Udomtanakunchai C, Reungpatthanaphong P, Tungjai M, Honikel L, Gordon CR, Rithidech KN. Late Effects of Low-Dose Radiation on the Bone Marrow, Lung, and Testis Collected From the Same Exposed BALB/cJ Mice. Dose Response 2018; 16:1559325818815031. [PMID: 30622448 PMCID: PMC6302279 DOI: 10.1177/1559325818815031] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 10/22/2018] [Accepted: 10/23/2018] [Indexed: 01/15/2023] Open
Abstract
We used 3 biological metrics highly relevant to health risks, that is, cell death, inflammation, and global DNA methylation, to determine the late effects of low doses (0.05 or 0.1 Gy) of 137Cs γ rays on the bone marrow, lung, and testis collected at 6 months post-irradiation from the same exposed BALB/cJ mouse. This integrative approach has not been used for such a purpose. Mice exposed to 0 or 1 Gy of radiation served as a sham or positive control group, respectively. The results could deliver information for better health risk assessment across tissues, including better scientific basis for radiation protection and clinical application. We found no changes in the levels of all studied biological metrics (except a significant increase in the levels of an anti-inflammatory cytokine, ie, interleukin 10) in tissues of 0.05-Gy exposed mice, when compared to those in sham controls. In contrast, significantly increased levels of cell death and inflammation, including a significant loss of global 5-hydroxymethylcytosine, were found in all tissues of the same mice exposed to 0.1 or 1.0 Gy. Our data demonstrated not only no harm but also hormesis in the 0.05-Gy exposed mice. However, the hormetic effect appears to be dependent on biological metrics and tissue.
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Affiliation(s)
- Witawat Jangiam
- Pathology Department, Stony Brook University, Stony Brook, NY, USA
- Department of Chemical Engineering, Burapha University, Chonburi, Thailand
| | - Chatchanok Udomtanakunchai
- Pathology Department, Stony Brook University, Stony Brook, NY, USA
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Paiboon Reungpatthanaphong
- Pathology Department, Stony Brook University, Stony Brook, NY, USA
- Department of Applied Radiation and Isotopes, Faculty of Sciences, Kasetsart University, Bangkok, Thailand
| | - Montree Tungjai
- Pathology Department, Stony Brook University, Stony Brook, NY, USA
- Department of Radiologic Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
| | - Louise Honikel
- Pathology Department, Stony Brook University, Stony Brook, NY, USA
| | - Chris R. Gordon
- Pathology Department, Stony Brook University, Stony Brook, NY, USA
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29
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Doss M. Are We Approaching the End of the Linear No-Threshold Era? J Nucl Med 2018; 59:1786-1793. [PMID: 30262515 DOI: 10.2967/jnumed.118.217182] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 09/24/2018] [Indexed: 12/12/2022] Open
Abstract
The linear no-threshold (LNT) model for radiation-induced cancer was adopted by national and international advisory bodies in the 1950s and has guided radiation protection policies worldwide since then. The resulting strict regulations have increased the compliance costs for the various uses of radiation, including nuclear medicine. The concerns about low levels of radiation due to the absence of a threshold have also resulted in adverse consequences. Justification of the LNT model was based on the concept that low levels of radiation increase mutations and that increased mutations imply increased cancers. This concept may not be valid. Low-dose radiation boosts defenses such as antioxidants and DNA repair enzymes. The boosted defenses would reduce the endogenous DNA damage that would have occurred in the subsequent period, and so the result would be reduced DNA damage and mutations. Whereas mutations are necessary for causing cancer, they are not sufficient since the immune system eliminates cancer cells or keeps them under control. The immune system plays an extremely important role in preventing cancer, as indicated by the substantially increased cancer risk in immune-suppressed patients. Hence, since low-dose radiation enhances the immune system, it would reduce cancers, resulting in a phenomenon known as radiation hormesis. There is considerable evidence for radiation hormesis and against the LNT model, including studies of atomic bomb survivors, background radiation, environmental radiation, cancer patients, medical radiation, and occupational exposures. Though Commentary 27 published by the National Council on Radiation Protection and Measurements concluded that recent epidemiologic studies broadly support the LNT model, a critical examination of the studies has shown that they do not. Another deficiency of Commentary 27 is that it did not consider the vast available evidence for radiation hormesis. Other advisory body reports that have supported the LNT model have similar deficiencies. Advisory bodies are urged to critically evaluate the evidence supporting both sides and arrive at an objective conclusion on the validity of the LNT model. Considering the strength of the evidence against the LNT model and the weakness of the evidence for it, the present analysis indicates that advisory bodies would be compelled to reject the LNT model. Hence, we may be approaching the end of the LNT model era.
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Affiliation(s)
- Mohan Doss
- Diagnostic Imaging, Fox Chase Cancer Center, Philadelphia, Pennsylvania
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30
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Doss M. The Conclusion of the BEIR VII Report Endorsing the Linear No-Threshold Model Is No Longer Valid Due to Advancement of Knowledge. J Nucl Med 2018; 59:1777. [PMID: 30072499 DOI: 10.2967/jnumed.118.217489] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 07/16/2018] [Indexed: 01/30/2023] Open
Affiliation(s)
- Mohan Doss
- Fox Chase Cancer Center 333 Cottman Ave. Philadelphia, PA 19111 E-mail:
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31
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Jin F, Luo HL, Zhou J, He YN, Liu XF, Zhong MS, Yang H, Li C, Li QC, Huang X, Tian XM, Qiu D, He GL, Yin L, Wang Y. Cancer risk assessment in modern radiotherapy workflow with medical big data. Cancer Manag Res 2018; 10:1665-1675. [PMID: 29970965 PMCID: PMC6021004 DOI: 10.2147/cmar.s164980] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Modern radiotherapy (RT) is being enriched by big digital data and intensive technology. Multimodality image registration, intelligence-guided planning, real-time tracking, image-guided RT (IGRT), and automatic follow-up surveys are the products of the digital era. Enormous digital data are created in the process of treatment, including benefits and risks. Generally, decision making in RT tries to balance these two aspects, which is based on the archival and retrieving of data from various platforms. However, modern risk-based analysis shows that many errors that occur in radiation oncology are due to failures in workflow. These errors can lead to imbalance between benefits and risks. In addition, the exact mechanism and dose-response relationship for radiation-induced malignancy are not well understood. The cancer risk in modern RT workflow continues to be a problem. Therefore, in this review, we develop risk assessments based on our current knowledge of IGRT and provide strategies for cancer risk reduction. Artificial intelligence (AI) such as machine learning is also discussed because big data are transforming RT via AI.
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Affiliation(s)
- Fu Jin
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Huan-Li Luo
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Juan Zhou
- Forensic Identification Center, College of Criminal Investigation, Southwest University of Political Science and Law, Chongqing, People’s Republic of China
| | - Ya-Nan He
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Xian-Feng Liu
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Ming-Song Zhong
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Han Yang
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Chao Li
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Qi-Cheng Li
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Xia Huang
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Xiu-Mei Tian
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Da Qiu
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Guang-Lei He
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Li Yin
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
| | - Ying Wang
- Department of Radiation Oncology, Chongqing University Cancer Hospital, Chongqing Cancer Institute, Chongqing Cancer Hospital, Chongqing, People’s Republic of China
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32
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Tulchinsky M, Baum RP, Bennet K, Freeman LM, Jong I, Kairemo K, Marcus CS, Moadel RM, Suman P. Well-Founded Recommendations for Radioactive Iodine Treatment of Differentiated Thyroid Cancer Require Balanced Study of Benefits and Harms. J Clin Oncol 2018; 36:1887-1888. [DOI: 10.1200/jco.2018.78.5972] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- Mark Tulchinsky
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Richard P. Baum
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - K.G. Bennet
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Leonard M. Freeman
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Ian Jong
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Kalevi Kairemo
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Carol S. Marcus
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Renee M. Moadel
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
| | - Paritosh Suman
- Mark Tulchinsky, Pennsylvania State University, Hershey, PA; Richard P. Baum, Theranostics Center for Molecular Radiotherapy and Molecular Imaging, Bad Berka, Germany; K.G. Bennet, American College of Nuclear Medicine, Downers Grove, IL; Leonard M. Freeman, Albert Einstein College of Medicine, Bronx, NY; Ian Jong, Monash Health, Melbourne, Victoria, Australia; Kalevi Kairemo, Docrates Cancer Center, Helsinki, Finland; Carol S. Marcus, David Geffen School of Medicine at University of California, Los
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33
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Vittecoq M, Giraudeau M, Sepp T, Marcogliese DJ, Klaassen M, Renaud F, Ujvari B, Thomas F. Turning natural adaptations to oncogenic factors into an ally in the war against cancer. Evol Appl 2018; 11:836-844. [PMID: 29928293 PMCID: PMC5999213 DOI: 10.1111/eva.12608] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 01/25/2018] [Indexed: 12/14/2022] Open
Abstract
Both field and experimental evolution studies have demonstrated that organisms naturally or artificially exposed to environmental oncogenic factors can, sometimes rapidly, evolve specific adaptations to cope with pollutants and their adverse effects on fitness. Although numerous pollutants are mutagenic and carcinogenic, little attention has been given to exploring the extent to which adaptations displayed by organisms living in oncogenic environments could inspire novel cancer treatments, through mimicking the processes allowing these organisms to prevent or limit malignant progression. Building on a substantial knowledge base from the literature, we here present and discuss this progressive and promising research direction, advocating closer collaboration between the fields of medicine, ecology, and evolution in the war against cancer.
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Affiliation(s)
- Marion Vittecoq
- Institut de Recherche de la Tour du Valat Arles France.,CREEC/MIVEGEC IRD CNRS University of Montpellier Montpellier France
| | - Mathieu Giraudeau
- School of Life Sciences Arizona State University Tempe AZ USA.,Centre for Ecology & Conservation College of Life and Environmental Sciences University of Exeter Penryn UK
| | - Tuul Sepp
- School of Life Sciences Arizona State University Tempe AZ USA.,Department of Zoology University of Tartu Tartu Estonia
| | - David J Marcogliese
- Aquatic Contaminants Research Division Water Science and Technology Directorate Environment and Climate Change Canada St. Lawrence Centre Montreal QC Canada.,Fisheries and Oceans Canada St. Andrews Biological Station St. Andrews NB Canada
| | - Marcel Klaassen
- School of Life and Environmental Sciences Centre for Integrative Ecology Deakin University Deakin Vic. Australia
| | - François Renaud
- CREEC/MIVEGEC IRD CNRS University of Montpellier Montpellier France
| | - Beata Ujvari
- School of Life and Environmental Sciences Centre for Integrative Ecology Deakin University Deakin Vic. Australia.,School of Biological Sciences University of Tasmania Hobart TAS Australia
| | - Frédéric Thomas
- CREEC/MIVEGEC IRD CNRS University of Montpellier Montpellier France
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Dobrzyński L, Fornalski KW, Reszczyńska J. Meta-analysis of thirty-two case-control and two ecological radon studies of lung cancer. JOURNAL OF RADIATION RESEARCH 2018; 59:149-163. [PMID: 29186473 PMCID: PMC5950923 DOI: 10.1093/jrr/rrx061] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Indexed: 05/04/2023]
Abstract
A re-analysis has been carried out of thirty-two case-control and two ecological studies concerning the influence of radon, a radioactive gas, on the risk of lung cancer. Three mathematically simplest dose-response relationships (models) were tested: constant (zero health effect), linear, and parabolic (linear-quadratic). Health effect end-points reported in the analysed studies are odds ratios or relative risk ratios, related either to morbidity or mortality. In our preliminary analysis, we show that the results of dose-response fitting are qualitatively (within uncertainties, given as error bars) the same, whichever of these health effect end-points are applied. Therefore, we deemed it reasonable to aggregate all response data into the so-called Relative Health Factor and jointly analysed such mixed data, to obtain better statistical power. In the second part of our analysis, robust Bayesian and classical methods of analysis were applied to this combined dataset. In this part of our analysis, we selected different subranges of radon concentrations. In view of substantial differences between the methodology used by the authors of case-control and ecological studies, the mathematical relationships (models) were applied mainly to the thirty-two case-control studies. The degree to which the two ecological studies, analysed separately, affect the overall results when combined with the thirty-two case-control studies, has also been evaluated. In all, as a result of our meta-analysis of the combined cohort, we conclude that the analysed data concerning radon concentrations below ~1000 Bq/m3 (~20 mSv/year of effective dose to the whole body) do not support the thesis that radon may be a cause of any statistically significant increase in lung cancer incidence.
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Affiliation(s)
- Ludwik Dobrzyński
- National Centre for Nuclear Research (NCBJ), ul. A. Sołtana 7, 05-400 Otwock-Świerk, Poland
- Corresponding author. National Centre for Nuclear Research (NCBJ), ul. A. Sołtana 7, 05-400 Otwock-Świerk, Poland. Tel: +48-22-273-1612; Fax: +48-22-77-93-481;
| | - Krzysztof W Fornalski
- PGE EJ 1, ul. Mysia 2, 00-496 Warszawa, Poland
- Ex-Polon Laboratory, ul. Podleśna 81a, 05-552 Łazy, Poland
| | - Joanna Reszczyńska
- National Centre for Nuclear Research (NCBJ), ul. A. Sołtana 7, 05-400 Otwock-Świerk, Poland
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35
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Mortazavi SMJ, Bevelacqua JJ, Fornalski KW, Welsh J, Doss M. Comments on "Space: The Final Frontier-Research Relevant to Mars". HEALTH PHYSICS 2018; 114:344-345. [PMID: 29360711 PMCID: PMC5784783 DOI: 10.1097/hp.0000000000000823] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Affiliation(s)
- S M J Mortazavi
- Department of Diagnostic Imaging, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran Bevelacqua Resources, 343 Adair Drive, Richland, WA 99352 Ex-Polon Laboratory, Podleśna 81a 05-552 Łazy, Poland and PGE EJ 1, Mokotowska 49, 00-542 Warszawa, Poland Department of Radiation Oncology, Loyola Stritch School of Medicine and Hines VA Hospital, Chicago, IL Department of Diagnostic Imaging, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111
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36
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Lemon JA, Phan N, Boreham DR. Single CT Scan Prolongs Survival by Extending Cancer Latency inTrp53Heterozygous Mice. Radiat Res 2017; 188:505-511. [DOI: 10.1667/rr14576.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Jennifer A. Lemon
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, Canada, P3E 2C6
| | - Nghi Phan
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Canada, L8S 4K1
| | - Douglas R. Boreham
- Medical Sciences Division, Northern Ontario School of Medicine, Sudbury, Canada, P3E 2C6
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37
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Jargin SV. Re: The high price of public fear of low-dose radiation. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2017; 37:797-799. [PMID: 28675752 DOI: 10.1088/1361-6498/aa7c69] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Sergei V Jargin
- People's Friendship University of Russia, Clementovski per 6-82, 115184 Moscow, Russia
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Mortazavi SMJ, Doss M. Comments on “Solid Cancer Incidence among the Life Span Study of Atomic Bomb Survivors: 1958-2009” (Radiat Res 2017; 187:513–537). Radiat Res 2017. [DOI: 10.1667/rr4811.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- SMJ Mortazavi
- Department of Diagnostic Imaging, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohan Doss
- Department of Diagnostic Imaging, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111
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Journy NMY, Lee C, Harbron RW, McHugh K, Pearce MS, Berrington de González A. Projected cancer risks potentially related to past, current, and future practices in paediatric CT in the United Kingdom, 1990-2020. Br J Cancer 2017; 116:109-116. [PMID: 27824812 PMCID: PMC5220140 DOI: 10.1038/bjc.2016.351] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 09/12/2016] [Accepted: 09/25/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND To project risks of developing cancer and the number of cases potentially induced by past, current, and future computed tomography (CT) scans performed in the United Kingdom in individuals aged <20 years. METHODS Organ doses were estimated from surveys of individual scan parameters and CT protocols used in the United Kingdom. Frequencies of scans were estimated from the NHS Diagnostic Imaging Dataset. Excess lifetime risks (ELRs) of radiation-related cancer were calculated as cumulative lifetime risks, accounting for survival probabilities, using the RadRAT risk assessment tool. RESULTS In 2000-2008, ELRs ranged from 0.3 to 1 per 1000 head scans and 1 to 5 per 1000 non-head scans. ELRs per scan were reduced by 50-70% in 2000-2008 compared with 1990-1995, subsequent to dose reduction over time. The 130 750 scans performed in 2015 in the United Kingdom were projected to induce 64 (90% uncertainty interval (UI): 38-113) future cancers. Current practices would lead to about 300 (90% UI: 230-680) future cancers induced by scans performed in 2016-2020. CONCLUSIONS Absolute excess risks from single exposures would be low compared with background risks, but even small increases in annual CT rates over the next years would substantially increase the number of potential subsequent cancers.
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Affiliation(s)
- Neige M Y Journy
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, MSC 9776, Bethesda, Maryland 20892, USA
| | - Choonsik Lee
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, MSC 9776, Bethesda, Maryland 20892, USA
| | - Richard W Harbron
- Institute of Health & Society, Newcastle University, Royal Victoria Infirmary, Queen Victoria Road, Newcastle-upon-Tyne NE1 4LP, UK
- NIHR Health Protection Research Unit in Chemical and Radiation Threats and Hazards, Newcastle University, Newcastle-upon-Tyne, UK
| | - Kieran McHugh
- Great Ormond Street Hospital for Children, Great Ormond Street, London WC1N 3JH, UK
| | - Mark S Pearce
- Institute of Health & Society, Newcastle University, Royal Victoria Infirmary, Queen Victoria Road, Newcastle-upon-Tyne NE1 4LP, UK
- NIHR Health Protection Research Unit in Chemical and Radiation Threats and Hazards, Newcastle University, Newcastle-upon-Tyne, UK
| | - Amy Berrington de González
- Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 9609 Medical Center Drive, MSC 9776, Bethesda, Maryland 20892, USA
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Power SP, Moloney F, Twomey M, James K, O’Connor OJ, Maher MM. Computed tomography and patient risk: Facts, perceptions and uncertainties. World J Radiol 2016; 8:902-915. [PMID: 28070242 PMCID: PMC5183924 DOI: 10.4329/wjr.v8.i12.902] [Citation(s) in RCA: 124] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Revised: 08/29/2016] [Accepted: 10/24/2016] [Indexed: 02/06/2023] Open
Abstract
Since its introduction in the 1970s, computed tomography (CT) has revolutionized diagnostic decision-making. One of the major concerns associated with the widespread use of CT is the associated increased radiation exposure incurred by patients. The link between ionizing radiation and the subsequent development of neoplasia has been largely based on extrapolating data from studies of survivors of the atomic bombs dropped in Japan in 1945 and on assessments of the increased relative risk of neoplasia in those occupationally exposed to radiation within the nuclear industry. However, the association between exposure to low-dose radiation from diagnostic imaging examinations and oncogenesis remains unclear. With improved technology, significant advances have already been achieved with regards to radiation dose reduction. There are several dose optimization strategies available that may be readily employed including omitting unnecessary images at the ends of acquired series, minimizing the number of phases acquired, and the use of automated exposure control as opposed to fixed tube current techniques. In addition, new image reconstruction techniques that reduce radiation dose have been developed in recent years with promising results. These techniques use iterative reconstruction algorithms to attain diagnostic quality images with reduced image noise at lower radiation doses.
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41
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Jargin SV. Debate on the Chernobyl Disaster: Response to Alison Rosamund Katz. INTERNATIONAL JOURNAL OF HEALTH SERVICES 2016; 47:150-159. [PMID: 27956579 DOI: 10.1177/0020731416679343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Siegel JA, Pennington CW, Sacks B. Subjecting Radiologic Imaging to the Linear No-Threshold Hypothesis: A Non Sequitur of Non-Trivial Proportion. J Nucl Med 2016; 58:1-6. [PMID: 27493264 DOI: 10.2967/jnumed.116.180182] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 07/18/2016] [Indexed: 12/11/2022] Open
Abstract
Radiologic imaging is claimed to carry an iatrogenic risk of cancer, based on an uninformed commitment to the 70-y-old linear no-threshold hypothesis (LNTH). Credible evidence of imaging-related low-dose (<100 mGy) carcinogenic risk is nonexistent; it is a hypothetical risk derived from the demonstrably false LNTH. On the contrary, low-dose radiation does not cause, but more likely helps prevent, cancer. The LNTH and its offspring, ALARA (as low as reasonably achievable), are fatally flawed, focusing only on molecular damage while ignoring protective, organismal biologic responses. Although some grant the absence of low-dose harm, they nevertheless advocate the "prudence" of dose optimization (i.e., using ALARA doses); but this is a radiophobia-centered, not scientific, approach. Medical imaging studies achieve a diagnostic purpose and should be governed by the highest science-based principles and policies. The LNTH is an invalidated hypothesis, and its use, in the form of ALARA dosing, is responsible for misguided concerns promoting radiophobia, leading to actual risks far greater than the hypothetical carcinogenic risk purportedly avoided. Further, the myriad benefits of imaging are ignored. The present work calls for ending the radiophobia caused by those asserting the need for dose optimization in imaging: the low-dose radiation of medical imaging has no documented pathway to harm, whereas the LNTH and ALARA most assuredly do.
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Affiliation(s)
| | - Charles W Pennington
- NAC International (retired), Norcross, Georgia, and executive nuclear energy consultant, Alpharetta, Georgia; and
| | - Bill Sacks
- U.S. Food and Drug Administration (retired), Green Valley, Arizona
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Sacks B, Meyerson G, Siegel JA. Epidemiology Without Biology: False Paradigms, Unfounded Assumptions, and Specious Statistics in Radiation Science (with Commentaries by Inge Schmitz-Feuerhake and Christopher Busby and a Reply by the Authors). BIOLOGICAL THEORY 2016; 11:69-101. [PMID: 27398078 PMCID: PMC4917595 DOI: 10.1007/s13752-016-0244-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 04/07/2016] [Indexed: 01/30/2023]
Abstract
Radiation science is dominated by a paradigm based on an assumption without empirical foundation. Known as the linear no-threshold (LNT) hypothesis, it holds that all ionizing radiation is harmful no matter how low the dose or dose rate. Epidemiological studies that claim to confirm LNT either neglect experimental and/or observational discoveries at the cellular, tissue, and organismal levels, or mention them only to distort or dismiss them. The appearance of validity in these studies rests on circular reasoning, cherry picking, faulty experimental design, and/or misleading inferences from weak statistical evidence. In contrast, studies based on biological discoveries demonstrate the reality of hormesis: the stimulation of biological responses that defend the organism against damage from environmental agents. Normal metabolic processes are far more damaging than all but the most extreme exposures to radiation. However, evolution has provided all extant plants and animals with defenses that repair such damage or remove the damaged cells, conferring on the organism even greater ability to defend against subsequent damage. Editors of medical journals now admit that perhaps half of the scientific literature may be untrue. Radiation science falls into that category. Belief in LNT informs the practice of radiology, radiation regulatory policies, and popular culture through the media. The result is mass radiophobia and harmful outcomes, including forced relocations of populations near nuclear power plant accidents, reluctance to avail oneself of needed medical imaging studies, and aversion to nuclear energy-all unwarranted and all harmful to millions of people.
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Affiliation(s)
- Bill Sacks
- />Center for Devices and Radiological Health, U.S. Food and Drug Administration, Green Valley, AZ USA
| | - Gregory Meyerson
- />Department of English, North Carolina Agricultural and Technical State University, Greensboro, NC USA
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Abstract
THERE IS considerable disagreement in the scientific community regarding the carcinogenicity of low-dose radiation (LDR), with publications supporting opposing points of view. However, major flaws have been identified in many of the publications claiming increased cancer risk from LDR. The data generally recognized as the most important for assessing radiation effects in humans, the atomic bomb survivor data, are often cited to raise LDR cancer concerns. However, these data no longer support the linear no-threshold (LNT) model after the 2012 update but are consistent with radiation hormesis. Thus, a resolution of the controversy regarding the carcinogenicity of LDR appears to be imminent, with the rejection of the LNT model and acceptance of radiation hormesis. Hence, for setting radiation protection regulations, an alternative approach to the present one based on the LNT model is needed. One approach would be to determine the threshold dose for the carcinogenic effect of radiation from existing data and establish regulations to ensure radiation doses are kept well below the threshold dose. This can be done by setting dose guidelines specifying safe levels of radiation doses, with the requirement that these safe levels, referred to as guidance levels, not be exceeded significantly. Using this approach, a dose guidance level of 10 cGy for acute radiation exposures and 10 cGy y for exposures over extended periods of time are recommended. The concept of keeping doses as low as reasonably achievable, known as ALARA, would no longer be required for low-level radiation exposures not expected to exceed the dose guidance levels significantly. These regulations would facilitate studies using LDR for prevention and treatment of diseases. Results from such studies would be helpful in refining dose guidance levels. The dose guidance levels would be the same for the public and radiation workers to ensure everyone's safety.
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Affiliation(s)
- Mohan Doss
- *Diagnostic Imaging, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111-2497
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45
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Jiang X, Baad M, Reiser I, Feinstein KA, Lu Z. Effect of comfort pads and incubator design on neonatal radiography. Pediatr Radiol 2016; 46:112-8. [PMID: 26335424 DOI: 10.1007/s00247-015-3450-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 07/09/2015] [Accepted: 08/06/2015] [Indexed: 12/21/2022]
Abstract
BACKGROUND There has been increasing interest in patient dose reduction in neonatal intensive care units. Removing comfort pads for radiography has been identified as a potential means to decrease patient dose. OBJECTIVE To assess the effect of comfort pads and support trays on detector entrance exposure (DEE) and image quality for neonatal radiography, and its implication for patient dose. MATERIALS AND METHODS Comfort pads and support trays from three incubator and warmer systems were examined. The attenuation of the primary beam by these structures was measured using a narrow beam geometry. Their effect on DEE and image quality was then assessed using typical neonatal chest radiography techniques with three configurations: 1) both the comfort pad and support included in the beam, 2) only the support tray included and 3) both the comfort pad and support tray removed. RESULTS Comfort pads and support trays were found to attenuate the primary beam by 6-15%. Eliminating these structures from the X-ray beam's path was found to increase the detector entrance exposure by 28-36% and increase contrast-to-noise ratio by more than 21%, suggesting room for patient dose reduction when the same image quality is maintained. CONCLUSION Comfort pads and tray support devices can have a considerable effect on DEE and image quality, with large variations among different incubator designs. Positioning the image detector directly underneath neonatal patients for radiography is a potential means for patient dose reduction. However, such benefit should be weighed against the risks of moving the patient.
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Affiliation(s)
- Xia Jiang
- Department of Radiology, University of Chicago Medicine, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637, USA.
| | - Michael Baad
- Department of Radiology, University of Chicago Medicine, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637, USA
| | - Ingrid Reiser
- Department of Radiology, University of Chicago Medicine, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637, USA
| | - Kate A Feinstein
- Department of Radiology, University of Chicago Medicine, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637, USA
| | - Zhengfeng Lu
- Department of Radiology, University of Chicago Medicine, 5841 S. Maryland Ave. MC 2026, Chicago, IL, 60637, USA
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Hormetic use of stress in gerontological interventions requires a cautious approach. Biogerontology 2015; 17:417-20. [PMID: 26712317 DOI: 10.1007/s10522-015-9630-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Accepted: 12/22/2015] [Indexed: 01/14/2023]
Abstract
Hormesis as a general principle is conceivable only for factors that are present in the natural environment. For such factors, existence of an optimal level can be assumed, which would correspond to the current environmental level or some average of historic levels. Theoretic basis of some hormetic mechanisms has been discussed within the scope of stress response pathways. Impacts of multiple stressing agents may produce combined effects larger than those expected from isolated impacts i.e. act synergistically. Adding the effect of a damaging stress to another damaging stress would possibly augment the damage; but if two mild stresses have positive hormetic effects, their combination can have additive positive effects. Potential adverse effects of excessive doses of hormetic agents should be pointed out particularly for senile age or a state close to decompensation when minor stimuli might be damaging. In conclusion, a hormetic use of stress in gerontological interventions requires a cautious approach.
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Doss M. INWORKS study: risk of leukaemia from protracted radiation exposure. LANCET HAEMATOLOGY 2015; 2:e404-5. [DOI: 10.1016/s2352-3026(15)00145-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Revised: 07/30/2015] [Accepted: 07/31/2015] [Indexed: 10/23/2022]
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Clanton R, Saucier D, Ford J, Akabani G. Microbial influences on hormesis, oncogenesis, and therapy: A review of the literature. ENVIRONMENTAL RESEARCH 2015; 142:239-256. [PMID: 26183884 DOI: 10.1016/j.envres.2015.06.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 06/11/2015] [Accepted: 06/23/2015] [Indexed: 06/04/2023]
Abstract
Utilization of environmental stimuli for growth is the main factor contributing to the evolution of prokaryotes and eukaryotes, independently and mutualistically. Epigenetics describes an organism's ability to vary expression of certain genes based on their environmental stimuli. The diverse degree of dose-dependent responses based on their variances in expressed genetic profiles makes it difficult to ascertain whether hormesis or oncogenesis has or is occurring. In the medical field this is shown where survival curves used in determining radiotherapeutic doses have substantial uncertainties, some as large as 50% (Barendsen, 1990). Many in-vitro radiobiological studies have been limited by not taking into consideration the innate presence of microbes in biological systems, which have either grown symbiotically or pathogenically. Present in-vitro studies neglect to take into consideration the varied responses that commensal and opportunistic pathogens will have when exposed to the same stimuli and how such responses could act as stimuli for their macro/microenvironment. As a result many theories such as radiation carcinogenesis explain microscopic events but fail to describe macroscopic events (Cohen, 1995). As such, this review shows how microorganisms have the ability to perturb risks of cancer and enhance hormesis after irradiation. It will also look at bacterial significance in the microenvironment of the tumor before and during treatment. In addition, bacterial systemic communication after irradiation and the host's immune responses to infection could explain many of the phenomena associated with bystander effects. Therefore, the present literature review considers the paradigms of hormesis and oncogenesis in order to find a rationale that ties them all together. This relationship was thus characterized to be the microbiome.
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Affiliation(s)
- Ryan Clanton
- Department of Nuclear Engineering, Texas A&M University, College Station, TX 77843, USA; Texas A&M Institute for Preclinical Studies, Texas A&M University, College Station, TX 77843, USA
| | - David Saucier
- Department of Nuclear Engineering, Texas A&M University, College Station, TX 77843, USA
| | - John Ford
- Department of Nuclear Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Gamal Akabani
- Department of Nuclear Engineering, Texas A&M University, College Station, TX 77843, USA; Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, TX 77843, USA; Texas A&M Institute for Preclinical Studies, Texas A&M University, College Station, TX 77843, USA
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Joo HM, Kang SJ, Nam SY, Yang KH, Kim CS, Lee IK, Kim JY. The Inhibitory Effects of Low-Dose Ionizing Radiation in IgE-Mediated Allergic Responses. PLoS One 2015; 10:e0136394. [PMID: 26317642 PMCID: PMC4552795 DOI: 10.1371/journal.pone.0136394] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 08/03/2015] [Indexed: 11/20/2022] Open
Abstract
Ionizing radiation has different biological effects according to dose and dose rate. In particular, the biological effect of low-dose radiation is unclear. Low-dose whole-body gamma irradiation activates immune responses in several ways. However, the effects and mechanism of low-dose radiation on allergic responses remain poorly understood. Previously, we reported that low-dose ionizing radiation inhibits mediator release in IgE-mediated RBL-2H3 mast cell activation. In this study, to have any physiological relevance, we investigated whether low-dose radiation inhibits allergic responses in activated human mast cells (HMC-1(5C6) and LAD2 cells), mouse models of passive cutaneous anaphylaxis and the late-phase cutaneous response. High-dose radiation induced cell death, but low-dose ionizing radiation of <0.5 Gy did not induce mast cell death. Low-dose ionizing radiation that did not induce cell death significantly suppressed mediator release from human mast cells (HMC-1(5C6) and LAD2 cells) that were activated by antigen-antibody reaction. To determine the inhibitory mechanism of mediator released by low-dose ionizing radiation, we examined the phosphorylation of intracellular signaling molecules such as Lyn, Syk, phospholipase Cγ, and protein kinase C, as well as the intracellular free Ca2+ concentration ([Ca2+]i). The phosphorylation of signaling molecules and [Ca2+]i following stimulation of FcεRI receptors was inhibited by low dose ionizing radiation. In agreement with its in vitro effect, ionizing radiation also significantly inhibited inflammatory cells infiltration, cytokine mRNA expression (TNF-α, IL-4, IL-13), and symptoms of passive cutaneous anaphylaxis reaction and the late-phase cutaneous response in anti-dinitrophenyl IgE-sensitized mice. These results indicate that ionizing radiation inhibits both mast cell-mediated immediate- and delayed-type allergic reactions in vivo and in vitro.
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Affiliation(s)
- Hae Mi Joo
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
| | - Su Jin Kang
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
| | - Seon Young Nam
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
| | - Kwang Hee Yang
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
| | - Cha Soon Kim
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
| | - In Kyung Lee
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
| | - Ji Young Kim
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro & Nuclear Power Co., Ltd., Seoul, Korea
- * E-mail:
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50
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Doss M. COUNTERPOINT: Should Radiation Dose From CT Scans Be a Factor in Patient Care? No. Chest 2015; 147:874-877. [DOI: 10.1378/chest.14-3022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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