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Kordrostami M, Sanjarian F, Shahbazi S, Ghasemi-Soloklui AA. Exploring low-dose gamma radiation effects on monoterpene biosynthesis in Thymus vulgaris: insights into plant defense mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:32842-32862. [PMID: 38668946 DOI: 10.1007/s11356-024-33269-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 04/05/2024] [Indexed: 05/29/2024]
Abstract
Thymus vulgaris, commonly known as thyme, is a plant renowned for producing monoterpenes. This study aimed to understand the effects of low-dose gamma radiation, specifically in the range of 1-5 Gy, on various traits of Thymus vulgaris, providing context on its importance in agricultural and medicinal applications. The research explored morpho-physiological, biochemical, and gene-expression responses in thyme plants under no gamma- and gamma-ray exposure conditions. The study revealed complex relationships between gamma-ray doses and plant characteristics. In particular, shoot and root lengths initially increased with low doses (1-3 Gy) but decreased at higher doses (5 Gy), suggesting a dose-dependent threshold effect. Similarly, shoot and root fresh weights displayed an initial increase followed by a decline with increasing doses. Biochemical parameters showed dose-dependent responses, with low to moderate doses (1-3 Gy) stimulating enzyme activities and high doses (5 Gy) inhibiting them. Gene expression analysis was focused on the following specific genes: thymol synthase, γ-terpinene synthase, and carvacrol synthase. Low to moderate doses increased the expression of these genes, resulting in increased production of bioactive compounds. However, higher doses had diminished effects or suppressed gene expression. Metabolite analysis demonstrated dose-dependent responses, with moderate doses enhancing secondary metabolite production, while higher doses provided limited benefits. These findings underscore the implications of using gamma radiation to enhance secondary metabolite production in plants and its potential applications in agriculture, medicine, and environmental science. The study emphasizes the potential of gamma radiation as an external stressor to influence plant responses and highlights the importance of understanding such effects in various fields.
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Affiliation(s)
- Mojtaba Kordrostami
- Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute (NSTRI), Karaj, Iran
| | - Forough Sanjarian
- Plant Bioproducts Department, Institute of Agricultural Biotechnology, National Institute of Genetic Engineering and Biotechnology, Tehran, Iran.
| | - Samira Shahbazi
- Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute (NSTRI), Karaj, Iran
| | - Ali Akbar Ghasemi-Soloklui
- Nuclear Agriculture Research School, Nuclear Science and Technology Research Institute (NSTRI), Karaj, Iran
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2
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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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3
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Orekhova NA, Modorov MV. Effects of environmental low-dose irradiation on functional-metabolic organ responses in a natural mouse population (Apodemus agrarius Pallas, 1771) within the East Urals Radioactive Trace (EURT) area, Russia. Int J Radiat Biol 2022; 98:1414-1423. [DOI: 10.1080/09553002.2022.2033340] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
- Natal´ya A. Orekhova
- Institute of Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences, st. Vos’mogo Marta 202, Yekaterinburg, 620144 Russia
| | - Makar V. Modorov
- Institute of Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences, st. Vos’mogo Marta 202, Yekaterinburg, 620144 Russia
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4
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Abu Hanifah NZH, Hashim S, Hassan HJ, Yusof NN, Bradley D. Radioactive material in cosmetic and healthcare products: Regulatory controls. Radiat Phys Chem Oxf Engl 1993 2021. [DOI: 10.1016/j.radphyschem.2021.109673] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Lopes MA, Coleman RR, Cremata EJ. Radiography and Clinical Decision-Making in Chiropractic. Dose Response 2021; 19:15593258211044844. [PMID: 34675758 PMCID: PMC8524714 DOI: 10.1177/15593258211044844] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2021] [Revised: 08/11/2021] [Accepted: 08/17/2021] [Indexed: 12/25/2022] Open
Abstract
The concern over x-ray exposure risks can overshadow the potential benefit of radiography, especially in cases where manual therapy is employed. Spinal malalignment cannot be accurately visualized without imaging. Manual therapy and the load tolerances of injured spinal tissues raise different criteria for the use of x-rays for spinal disorders than in medical practice. Current regulatory bodies rely on radiography risk assessments based on Linear-No-Threshold (LNT) risk models. There is a need to consider radiography guidelines for chiropractic which are different from those for medical practice. Radiography practice guidelines are summaries dominated by frequentist interpretations in the analysis of data from studies. In contrast, clinicians often employ a pseudo-Bayesian form of reasoning during the clinical decision-making process. The overrepresentation of frequentist perspectives in evidence-based practice guidelines alter decision-making away from practical assessment of a patient's needs, toward an overly cautious standard applied to patients without regard to their risk/benefit likelihoods relating to radiography. Guidelines for radiography in chiropractic to fully assess the condition of the spine and spinal alignment prior to manual therapy, especially with high velocity, low amplitude spinal manipulation (HVLA-SM), should necessarily differ from those used in medical practice.
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Affiliation(s)
- Mark A. Lopes
- Gonstead Clinical Studies Society, Santa Cruz, CA, USA
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6
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Karam HM, Radwan RR. Low dose γ radiation enhances antidepressant effect of resveratrol: Behavioral and neurochemical studies. ENVIRONMENTAL TOXICOLOGY 2020; 35:1137-1145. [PMID: 32463565 DOI: 10.1002/tox.22949] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 03/09/2020] [Accepted: 05/06/2020] [Indexed: 06/11/2023]
Abstract
The low dose of radiation (LDR) has received growing attention for its beneficial neuroprotective effect. This study was designed to investigate the enhancing effect of LDR on the antidepressant potential of resveratrol against diazepam-induced depression in mice. Female mice divided into five groups; control, diazepam (2 mg/kg), LDR (0.5Gy) + diazepam, resveratrol (20 mg/kg) + diazepam, LDR + resveratrol+diazepam. Mice received diazepam showed depressive symptoms as evidenced by decreased locomotor activity in the open field and increased immobility time in the forced swimming and tail suspension tests integrated with a marked decline in biogenic amines (serotonin, norepinephrine, and dopamine) in brain tissues. These effects were ameliorated by LDR or resveratrol administration demonstrating an antidepressant activity. Interestingly, LDR triggered the antidepressant effect of resveratrol as it restored the changes in behavioral tests, neurotransmitters, and neuro-histoarchitecture. In conclusion, these findings suggested that LDR could be considered as a novel adjuvant that augmented the resveratrol antidepressant effect and might serve as a potential therapeutic approach for depression.
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Affiliation(s)
- Heba M Karam
- Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Nasr City, Cairo, Egypt
| | - Rasha R Radwan
- Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Nasr City, Cairo, Egypt
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7
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Younger C, Wagner M, Douglas C, Warren-Forward H. Describing ionising radiation risk in the clinical setting: A systematic review. Radiography (Lond) 2019; 25:83-90. [DOI: 10.1016/j.radi.2018.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 11/07/2018] [Accepted: 11/09/2018] [Indexed: 10/27/2022]
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8
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Stone J, Mitrofanis J, Johnstone DM, Falsini B, Bisti S, Adam P, Nuevo AB, George-Weinstein M, Mason R, Eells J. Acquired Resilience: An Evolved System of Tissue Protection in Mammals. Dose Response 2018; 16:1559325818803428. [PMID: 30627064 PMCID: PMC6311597 DOI: 10.1177/1559325818803428] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 08/22/2018] [Accepted: 08/29/2018] [Indexed: 12/11/2022] Open
Abstract
This review brings together observations on the stress-induced regulation of resilience mechanisms in body tissues. It is argued that the stresses that induce tissue resilience in mammals arise from everyday sources: sunlight, food, lack of food, hypoxia and physical stresses. At low levels, these stresses induce an organised protective response in probably all tissues; and, at some higher level, cause tissue destruction. This pattern of response to stress is well known to toxicologists, who have termed it hormesis. The phenotypes of resilience are diverse and reports of stress-induced resilience are to be found in journals of neuroscience, sports medicine, cancer, healthy ageing, dementia, parkinsonism, ophthalmology and more. This diversity makes the proposing of a general concept of induced resilience a significant task, which this review attempts. We suggest that a system of stress-induced tissue resilience has evolved to enhance the survival of animals. By analogy with acquired immunity, we term this system 'acquired resilience'. Evidence is reviewed that acquired resilience, like acquired immunity, fades with age. This fading is, we suggest, a major component of ageing. Understanding of acquired resilience may, we argue, open pathways for the maintenance of good health in the later decades of human life.
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Affiliation(s)
- Jonathan Stone
- Discipline of Physiology, Bosch Institute of Medical Research, University of Sydney, Sydney, New South Wales, Australia
| | - John Mitrofanis
- Discipline of Anatomy and Histology, Bosch Institute of Medical Research, University of Sydney, Sydney, New South Wales, Australia
| | - Daniel M. Johnstone
- Discipline of Physiology, Bosch Institute of Medical Research, University of Sydney, Sydney, New South Wales, Australia
| | - Benedetto Falsini
- Facolta’ di Medicina e Chirurgia, Fondazione Policlinico A. Gemelli, Universita’ Cattolica del S. Cuore, Rome, Italy
| | - Silvia Bisti
- Department of Biotechnical and Applied Clinical Sciences, Università degli Studi dell’Aquila, IIT Istituto Italiano di Tecnologia Genova and INBB Istituto Nazionale Biosistemi e Biostrutture, Rome, Italy
| | - Paul Adam
- School of Biological, Earth and Environmental Science, University of New South Wales, Sydney, New South Wales, Australia
| | - Arturo Bravo Nuevo
- Department of Biomedical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, USA
| | - Mindy George-Weinstein
- Department of Biomedical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA, USA
| | - Rebecca Mason
- Discipline of Physiology, Bosch Institute of Medical Research, University of Sydney, Sydney, New South Wales, Australia
| | - Janis Eells
- College of Health Sciences, University of Wisconsin, Milwaukee, WI, USA
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9
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Lim MYT, Manzon RG, Somers CM, Boreham DR, Wilson JY. Impacts of temperature, morpholine, and chronic radiation on the embryonic development of round whitefish (Prosopium cylindraceum). ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2018; 37:2593-2608. [PMID: 29963715 DOI: 10.1002/etc.4219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/10/2018] [Accepted: 06/28/2018] [Indexed: 06/08/2023]
Abstract
During incubation, round whitefish embryos may experience fluctuating or elevated temperatures from natural (e.g., seasonal temperature changes) and/or anthropogenic sources. Anthropogenic sources like once-through cooling discharges from nuclear power plants can also expose embryos to chemicals (e.g., morpholine) and/or radiation. To examine the effects of these potential stressors on embryogenesis, round whitefish were incubated under fluctuating or constant temperatures, with morpholine or 137 Cs gamma rays. We report the percentage of prehatch and posthatch mortality, developmental rate, hatch dynamics, and morphometrics at 4 development stages. Embryos reared at constant temperatures had delayed developmental stage onset and median hatch, higher mortality at constant 8 °C, and lower mortality at ≤5 °C, compared with embryos reared under seasonal temperature regimes. Embryos incubated with ≥500 mg L-1 morpholine (>200× regulatory limits) had advanced hatch, reduced body size, and increased prehatch (100% at 1000 mg L-1 ) and posthatch (≈95% at 500 mg L-1 ) mortality compared with controls. Relative to controls, embryos irradiated with ≥0.16 mGy/d had larger body mass early in development, and all irradiated embryos had decreased posthatch mortality; the lowest dose was >300× discharge limits. Our study suggests that fluctuating or elevated temperatures and high-dose morpholine can alter development rate, hatch dynamics, and growth, and/or increase mortality compared with embryos reared at constant temperatures of ≤5 °C; conversely, low-dose irradiation had transient developmental effects but may benefit early posthatch survival. Environ Toxicol Chem 2018;37:2593-2608. © 2018 SETAC.
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Affiliation(s)
- Michael Y-T Lim
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
| | - Richard G Manzon
- Department of Biology, University of Regina, Regina, Saskatchewan, Canada
| | | | | | - Joanna Y Wilson
- Department of Biology, McMaster University, Hamilton, Ontario, Canada
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10
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Abstract
Hormesis can be explained by evolutionary adaptation to the current level of a factor present in the natural environment or to some average from the past. This pertains also to ionizing radiation as the natural background has been decreasing during the time of the life existence. DNA damage and repair are normally in a dynamic balance. The conservative nature of the DNA repair suggests that cells may have retained some capability to repair damage from higher radiation levels than that existing today. According to this concept, the harm caused by radioactive contamination would tend to zero with a dose rate tending to a wide range level of the natural radiation background. Existing evidence in favor of hormesis is substantial, experimental data being partly at variance with results of epidemiological studies. Potential bias, systematic errors, and motives to exaggerate risks from low-dose low-rate ionizing radiation are discussed here. In conclusion, current radiation safety norms are exceedingly restrictive and should be revised on the basis of scientific evidence. Elevation of the limits must be accompanied by measures guaranteeing their observance.
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Affiliation(s)
- S V Jargin
- Peoples' Friendship University of Russia, Moscow, Russian Federation
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11
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The effect of well-characterized, very low-dose x-ray radiation on fibroblasts. PLoS One 2018; 13:e0190330. [PMID: 29300773 PMCID: PMC5754078 DOI: 10.1371/journal.pone.0190330] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 12/12/2017] [Indexed: 11/19/2022] Open
Abstract
The purpose of this study is to determine the effects of low-dose radiation on fibroblast cells irradiated by spectrally and dosimetrically well-characterized soft x-rays. To achieve this, a new cell culture x-ray irradiation system was designed. This system generates characteristic fluorescent x-rays to irradiate the cell culture with x-rays of well-defined energies and doses. 3T3 fibroblast cells were cultured in cups with Mylar® surfaces and were irradiated for one hour with characteristic iron (Fe) K x-ray radiation at a dose rate of approximately 550 μGy/hr. Cell proliferation, total protein analysis, flow cytometry, and cell staining were performed on fibroblast cells to determine the various effects caused by the radiation. Irradiated cells demonstrated increased proliferation and protein production compared to control samples. Flow cytometry revealed that a higher percentage of irradiated cells were in the G0/G1 phase of the cell cycle compared to control counterparts, which is consistent with other low-dose studies. Cell staining results suggest that irradiated cells maintained normal cell functions after radiation exposure, as there were no qualitative differences between the images of the control and irradiated samples. The result of this study suggest that low-dose soft x-ray radiation might cause an initial pause, followed by a significant increase, in proliferation. An initial “pause” in cell proliferation could be a protective mechanism of the cells to minimize DNA damage caused by radiation exposure. The new cell irradiation system developed here allows for unprecedented control over the properties of the x-rays given to the cell cultures. This will allow for further studies on various cell types with known spectral distribution and carefully measured doses of radiation, which may help to elucidate the mechanisms behind varied cell responses to low-dose x-rays reported in the literature.
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12
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Rigsby CK, McKenney SE, Hill KD, Chelliah A, Einstein AJ, Han BK, Robinson JD, Sammet CL, Slesnick TC, Frush DP. Radiation dose management for pediatric cardiac computed tomography: a report from the Image Gently 'Have-A-Heart' campaign. Pediatr Radiol 2018; 48:5-20. [PMID: 29292481 PMCID: PMC6230472 DOI: 10.1007/s00247-017-3991-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2017] [Revised: 08/21/2017] [Accepted: 09/12/2017] [Indexed: 12/28/2022]
Abstract
Children with congenital or acquired heart disease can be exposed to relatively high lifetime cumulative doses of ionizing radiation from necessary medical imaging procedures including radiography, fluoroscopic procedures including diagnostic and interventional cardiac catheterizations, electrophysiology examinations, cardiac computed tomography (CT) studies, and nuclear cardiology examinations. Despite the clinical necessity of these imaging studies, the related ionizing radiation exposure could pose an increased lifetime attributable cancer risk. The Image Gently "Have-A-Heart" campaign is promoting the appropriate use of medical imaging studies in children with congenital or acquired heart disease while minimizing radiation exposure. The focus of this manuscript is to provide a comprehensive review of radiation dose management and CT performance in children with congenital or acquired heart disease.
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Affiliation(s)
- Cynthia K Rigsby
- Department of Medical Imaging #9, Ann & Robert H. Lurie Children's Hospital of Chicago, Departments of Radiology and Pediatrics, Northwestern University Feinberg School of Medicine, 225 E. Chicago Ave., Chicago, IL, 60611, USA.
| | - Sarah E McKenney
- Division of Diagnostic Imaging and Radiology, Children's National Medical Center, Washington, DC, USA
| | - Kevin D Hill
- Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
| | - Anjali Chelliah
- Division of Pediatric Cardiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, NY, USA
| | - Andrew J Einstein
- Division of Cardiology, Departments of Medicine and Radiology, Columbia University Medical Center and New York-Presbyterian Hospital, New York, NY, USA
| | - B Kelly Han
- Department of Pediatrics, Children's Heart Clinic at The Children's Hospitals and Clinics of Minnesota, Minneapolis, MN, USA
| | - Joshua D Robinson
- Division of Pediatric Cardiology, Ann & Robert H. Lurie Children's Hospital of Chicago, Departments of Pediatrics and Radiology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
| | - Christina L Sammet
- Department of Medical Imaging #9, Ann & Robert H. Lurie Children's Hospital of Chicago, Departments of Radiology and Pediatrics, Northwestern University Feinberg School of Medicine, 225 E. Chicago Ave., Chicago, IL, 60611, USA
| | - Timothy C Slesnick
- Department of Pediatrics, Emory University School of Medicine, Children's Healthcare of Atlanta, Atlanta, GA, USA
| | - Donald P Frush
- Department of Radiology, Duke University Medical Center, Durham, NC, USA
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Thome C, Mitz C, Hulley EN, Somers CM, Manzon RG, Wilson JY, Boreham DR. Initial Characterization of the Growth Stimulation and Heat-Shock-Induced Adaptive Response in Developing Lake Whitefish Embryos after Ionizing Radiation Exposure. Radiat Res 2017; 188:475-485. [DOI: 10.1667/rr14574.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Christopher Thome
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Canada
| | - Charles Mitz
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Canada
| | - Emily N. Hulley
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Canada
| | | | | | | | - Douglas R. Boreham
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Canada
- Northern Ontario School of Medicine, Sudbury, Canada
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Paradoxical effects of 137Cs irradiation on pharmacological stimulation of reactive oxygen species in hippocampal slices from apoE2 and apoE4 mice. Oncotarget 2017; 8:76587-76605. [PMID: 29100334 PMCID: PMC5652728 DOI: 10.18632/oncotarget.20603] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 08/17/2017] [Indexed: 11/29/2022] Open
Abstract
In humans, apoE, which plays a role in repair, is expressed in three isoforms: E2, E3, and E4. E4 is a risk factor for age-related cognitive decline (ACD) and Alzheimer's disease (AD), particularly in women. In contrast, E2 is a protective factor for ACD and AD. E2 and E4 might also differ in their response to cranial 137Cs irradiation, a form of radiation typically used in a clinical setting for the treatment of cancer. This might be mediated by reactive oxygen species (ROS) in an-apoE isoform-dependent fashion. E2 and E4 female mice received sham-irradiation or cranial irradiation at 8 weeks of age and a standard mouse chow or a diet supplemented with the antioxidant alpha-lipoic acid (ALA) starting at 6 weeks of age. Behavioral and cognitive performance of the mice were assessed 12 weeks later. Subsequently, the generation of ROS in hippocampal slices was analyzed. Compared to sham-irradiated E4 mice, irradiated E4 mice showed enhanced spatial memory in the water maze. This was associated with increased hippocampal PMA-induction of ROS. Similar effects were not seen in E2 mice. Irradiation increased endogenous hippocampal ROS levels in E2 mice while decreasing those in E4 mice. NADPH activity and MnSOD levels were higher in sham-irradiated E2 than E4 mice. Irradiation increased NADPH activity and MnSOD levels in hemi brains of E4 mice but not in those of E2 mice. ALA did not affect behavioral and cognitive performance or hippocampal formation of ROS in either genotype. Thus, apoE isoforms modulate the radiation response.
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Frush DP, Perez MDR. Children, medical radiation and the environment: An important dialogue. ENVIRONMENTAL RESEARCH 2017; 156:358-363. [PMID: 28391175 DOI: 10.1016/j.envres.2017.04.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 02/27/2017] [Accepted: 04/02/2017] [Indexed: 06/07/2023]
Abstract
There are unique considerations in the medical care of children, which includes the use of medical imaging. Medical imaging is frequently necessary and is essential in diagnosis and management of children with illness and injury. Much of medical imaging requires ionizing radiation. While virtually all diagnostic imaging radiation is considered low-dose level, there is still a broad misperception about what modalities use ionizing radiation and how much radiation risk exists in the medical environment. A discussion of radiation exposure is especially relevant in children due to their increased vulnerability, including to radiation-induced cancer. Ionizing radiation is both naturally occurring and man-made, including medical sources that have been increasing over the past few decades and can vary in radiation dose both between different modalities and for similar examinations. Perspectives vary regarding cancer risk and levels of radiation resulting from diagnostic imaging, however most medical and scientific organization support the perspective that the risk of cancer at these levels is uncertain. It is important to have balanced and informed resources for the use of ionizing radiation in the care of children, and it is equally important to assure that the delivery of this content is appropriate to the audience to which it is intended. For these reasons, it is valuable to review the issues related to use of ionizing radiation in medical imaging in children.
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Affiliation(s)
- Donald P Frush
- Department of Radiology, Duke University Medical Center, 1905 McGovern-Davison Children's Health Center, Durham, NC 27710, USA.
| | - Maria Del Rosario Perez
- Department of Public Health, Environmental and Social Determinants of Health (PHE), Cluster of Family, Women's and Children's Health (FWC), World Health Organization (WHO), Geneva, Switzerland
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16
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Exaptation, serendipity and aging. Mech Ageing Dev 2017; 163:30-35. [PMID: 28089621 DOI: 10.1016/j.mad.2017.01.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 11/09/2016] [Accepted: 01/05/2017] [Indexed: 11/23/2022]
Abstract
The paper shows the importance of serendipity and exaptation in selected key moments of ageing research and argue that rationalistic dominant models in scientific research have masked the importance of reverse models of discovery based on serendipity and exaptation. I ask why this is the case and analyze three contributing factors: unprestatability of the functions of technologies, multidimensionality and astronomical complexity of the space over which biological reactions occurs and role of scientific paradigms in channeling research toward incrementalism. Empirical evidence of the limits of the rationalistic models are presented next. I close the paper by discussing the implications for aging research.
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Web of Science, Scopus, and Google Scholar citation rates: a case study of medical physics and biomedical engineering: what gets cited and what doesn't? AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE 2016; 39:817-823. [PMID: 27578318 DOI: 10.1007/s13246-016-0478-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 08/22/2016] [Indexed: 10/21/2022]
Abstract
There are often differences in a publication's citation count, depending on the database accessed. Here, aspects of citation counts for medical physics and biomedical engineering papers are studied using papers published in the journal Australasian physical and engineering sciences in medicine. Comparison is made between the Web of Science, Scopus, and Google Scholar. Papers are categorised into subject matter, and citation trends are examined. It is shown that review papers as a group tend to receive more citations on average; however the highest cited individual papers are more likely to be research papers.
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Hess CB, Thompson HM, Benedict SH, Seibert JA, Wong K, Vaughan AT, Chen AM. Exposure Risks Among Children Undergoing Radiation Therapy: Considerations in the Era of Image Guided Radiation Therapy. Int J Radiat Oncol Biol Phys 2016; 94:978-92. [PMID: 27026304 DOI: 10.1016/j.ijrobp.2015.12.372] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Revised: 11/30/2015] [Accepted: 12/22/2015] [Indexed: 12/14/2022]
Abstract
Recent improvements in toxicity profiles of pediatric oncology patients are attributable, in part, to advances in the field of radiation oncology such as intensity modulated radiation (IMRT) and proton therapy (IMPT). While IMRT and IMPT deliver highly conformal dose to targeted volumes, they commonly demand the addition of 2- or 3-dimensional imaging for precise positioning--a technique known as image guided radiation therapy (IGRT). In this manuscript we address strategies to further minimize exposure risk in children by reducing effective IGRT dose. Portal X rays and cone beam computed tomography (CBCT) are commonly used to verify patient position during IGRT and, because their relative radiation exposure is far less than the radiation absorbed from therapeutic treatment beams, their sometimes significant contribution to cumulative risk can be easily overlooked. Optimizing the conformality of IMRT/IMPT while simultaneously ignoring IGRT dose may result in organs at risk being exposed to a greater proportion of radiation from IGRT than from therapeutic beams. Over a treatment course, cumulative central-axis CBCT effective dose can approach or supersede the amount of radiation absorbed from a single treatment fraction, a theoretical increase of 3% to 5% in mutagenic risk. In select scenarios, this may result in the underprediction of acute and late toxicity risk (such as azoospermia, ovarian dysfunction, or increased lifetime mutagenic risk) in radiation-sensitive organs and patients. Although dependent on variables such as patient age, gender, weight, body habitus, anatomic location, and dose-toxicity thresholds, modifying IGRT use and acquisition parameters such as frequency, imaging modality, beam energy, current, voltage, rotational degree, collimation, field size, reconstruction algorithm, and documentation can reduce exposure, avoid unnecessary toxicity, and achieve doses as low as reasonably achievable, promoting a culture and practice of "gentle IGRT."
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Affiliation(s)
- Clayton B Hess
- Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California
| | - Holly M Thompson
- Department of Diagnostic Radiology, University of California Davis Medical Center, Sacramento, California
| | - Stanley H Benedict
- Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California
| | - J Anthony Seibert
- Department of Diagnostic Radiology, University of California Davis Medical Center, Sacramento, California
| | - Kenneth Wong
- Department of Radiation Oncology, University of California Los Angeles Jonsson Comprehensive Cancer Center, University of California David Geffen School of Medicine, Los Angeles, California
| | - Andrew T Vaughan
- Department of Radiation Oncology, University California Davis Comprehensive Cancer Center, Sacramento, California
| | - Allen M Chen
- Department of Radiation Oncology, University of California Los Angeles Jonsson Comprehensive Cancer Center, University of California David Geffen School of Medicine, Los Angeles, California.
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Microsimulation model of CT versus MRI surveillance of Bosniak IIF renal cystic lesions: should effects of radiation exposure affect selection of imaging strategy? AJR Am J Roentgenol 2015; 203:W629-36. [PMID: 25415728 DOI: 10.2214/ajr.14.12550] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The objective of this study was to quantify the effects of radiation-induced cancer risks in patients with Bosniak category IIF lesions undergoing CT versus MRI surveillance. MATERIALS AND METHODS We developed a Markov-Monte Carlo model to determine life expectancy losses attributable to radiation-induced cancers in hypothetical patients undergoing CT versus MRI surveillance of Bosniak IIF lesions. Our model tracked hypothetical patients as they underwent imaging surveillance for up to 5 years, accounting for potential lesion progression and treatment. Estimates of radiation-induced cancer mortality were generated using a published organ-specific radiation-risk model based on Biological Effects of Ionizing Radiation VII methods. The model also incorporated surgical mortality and renal cancer-specific mortality. Our primary outcome was life expectancy loss attributable to radiation-induced cancers. A sensitivity analysis was performed to assess the stability of the results with variability in key parameters. RESULTS The mean number of examinations per patient was 6.3. In the base case, assuming 13 mSv per multiphase CT examination, 64-year-old men experienced an average life expectancy decrease of 5.5 days attributable to radiation-induced cancers from CT; 64-year-old women experienced a corresponding life expectancy loss of 6.9 days. The results were most sensitive to patient age: Life expectancy loss attributable to radiation-induced cancers increased to 21.6 days in 20-year-old women and 20.0 days in 20-year-old men. Varied assumptions of each modality's (CT vs MRI) depiction of lesion complexity also impacted life expectancy losses. CONCLUSION Microsimulation modeling shows that radiation-induced cancer risks from CT surveillance for Bosniak IIF lesions minimally affect life expectancy. However, as progressively younger patients are considered, increasing radiation risks merit stronger consideration of MRI surveillance.
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The fisherman's cards: how to address past and future radiation exposures in clinical decision making. AJR Am J Roentgenol 2014; 202:362-7. [PMID: 24450678 DOI: 10.2214/ajr.13.10896] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE. The purpose of this article is to describe how to address patients' past-and future potential-radiation exposures when making an imaging decision in a given situation. CONCLUSION. The Biologic Effects of Ionizing Radiation committee has endorsed a linear no-threshold model to explain the relationship between radiation exposure and cancer risk. This model implies that past and future potential exposures should not impact current decisions. We present an analogy that deconstructs these counterintuitive conclusions and facilitates translation of key radiation risk principles to practice.
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Yu HS, Liu ZM, Yu XY, Song AQ, Liu N, Wang H. Low-dose radiation induces antitumor effects and erythrocyte system hormesis. Asian Pac J Cancer Prev 2014; 14:4121-6. [PMID: 23991963 DOI: 10.7314/apjcp.2013.14.7.4121] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE Low dose radiation may stimulate the growth and development of animals, increase life span, enhance fertility, and downgrade the incidence of tumor occurrence.The aim of this study was to investigate the antitumor effect and hormesis in an erythrocyte system induced by low-dose radiation. METHODS Kunming strain male mice were subcutaneously implanted with S180 sarcoma cells in the right inguen as an experimental in situ animal model. Six hours before implantation, the mice were given 75mGy whole body X-ray radiation. Tumor growth was observed 5 days later, and the tumor volume was calculated every other day. Fifteen days later, all mice were killed to measure the tumor weight, and to observe necrotic areas and tumor-infiltration-lymphoreticular cells (TILs). At the same time, erythrocyte immune function and the level of 2,3-diphosphoglyceric acid (2,3- DPG) were determined. Immunohistochemical staining was used to detect the expression of EPO and VEGFR of tumor tissues. RESULTS The mice pre-exposed to low dose radiation had a lower tumor formation rate than those without low dose radiation (P < 0.05). The tumor growth slowed down significantly in mice pre-exposed to low dose radiation; the average tumor weight in mice pre-exposed to low dose radiation was lighter too (P < 0.05). The tumor necrosis areas were larger and TILs were more in the radiation group than those of the group without radiation. The erythrocyte immune function, the level of 2,3-DPG in the low dose radiation group were higher than those of the group without radiation (P < 0.05). After irradiation the expression of EPO of tumor tissues in LDR group decreased with time. LDR-24h, LDR-48h and LDR-72h groups were all statistically significantly different from sham-irradiation group. The expression of VEGFR also decreased, and LDR-24h group was the lowest (P < 0.05). CONCLUSION Low dose radiation could markedly increase the anti-tumor ability of the organism and improve the erythrocyte immune function and the ability of carrying O2. Low-dose total body irradiation, within a certain period of time, can decrease the expression of hypoxia factor EPO and VEGFR, which may improve the situation of tumor hypoxia and radiosensitivity of tumor itself.
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Affiliation(s)
- Hong-Sheng Yu
- Department of Oncology, the Affiliated Hospital of Medical College, Qingdao University, Qingdao, China.
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22
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Manda K, Kavanagh JN, Buttler D, Prise KM, Hildebrandt G. Low dose effects of ionizing radiation on normal tissue stem cells. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2014; 761:6-14. [PMID: 24566131 DOI: 10.1016/j.mrrev.2014.02.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 02/03/2014] [Accepted: 02/13/2014] [Indexed: 12/18/2022]
Abstract
In recent years, there has been growing evidence for the involvement of stem cells in cancer initiation. As a result of their long life span, stem cells may have an increased propensity to accumulate genetic damage relative to differentiated cells. Therefore, stem cells of normal tissues may be important targets for radiation-induced carcinogenesis. Knowledge of the effects of ionizing radiation (IR) on normal stem cells and on the processes involved in carcinogenesis is very limited. The influence of high doses of IR (>5Gy) on proliferation, cell cycle and induction of senescence has been demonstrated in stem cells. There have been limited studies of the effects of moderate (0.5-5Gy) and low doses (<0.5Gy) of IR on stem cells however, the effect of low dose IR (LD-IR) on normal stem cells as possible targets for radiation-induced carcinogenesis has not been studied in any depth. There may also be important parallels between stem cell responses and those of cancer stem cells, which may highlight potential key common mechanisms of their response and radiosensitivity. This review will provide an overview of the current knowledge of radiation-induced effects on normal stem cells, with particular focus on low and moderate doses of IR.
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Affiliation(s)
- Katrin Manda
- Department of Radiotherapy and Radiation Oncology, University of Rostock, Suedring 75, 18059 Rostock, Germany.
| | - Joy N Kavanagh
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom.
| | - Dajana Buttler
- Department of Radiotherapy and Radiation Oncology, University of Rostock, Suedring 75, 18059 Rostock, Germany.
| | - Kevin M Prise
- Centre for Cancer Research and Cell Biology, Queen's University Belfast, 97 Lisburn Road, Belfast BT9 7BL, United Kingdom.
| | - Guido Hildebrandt
- Department of Radiotherapy and Radiation Oncology, University of Rostock, Suedring 75, 18059 Rostock, Germany.
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Abstract
The atomic bomb survivor cancer mortality data have been used in the past to justify the use of the linear no-threshold (LNT) model for estimating the carcinogenic effects of low dose radiation. An analysis of the recently updated atomic bomb survivor cancer mortality dose-response data shows that the data no longer support the LNT model but are consistent with a radiation hormesis model when a correction is applied for a likely bias in the baseline cancer mortality rate. If the validity of the phenomenon of radiation hormesis is confirmed in prospective human pilot studies, and is applied to the wider population, it could result in a considerable reduction in cancers. The idea of using radiation hormesis to prevent cancers was proposed more than three decades ago, but was never investigated in humans to determine its validity because of the dominance of the LNT model and the consequent carcinogenic concerns regarding low dose radiation. Since cancer continues to be a major health problem and the age-adjusted cancer mortality rates have declined by only ∼10% in the past 45 years, it may be prudent to investigate radiation hormesis as an alternative approach to reduce cancers. Prompt action is urged.
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Manda K, Glasow A, Paape D, Hildebrandt G. Effects of ionizing radiation on the immune system with special emphasis on the interaction of dendritic and T cells. Front Oncol 2012; 2:102. [PMID: 22937525 PMCID: PMC3426842 DOI: 10.3389/fonc.2012.00102] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2012] [Accepted: 07/31/2012] [Indexed: 01/01/2023] Open
Abstract
Dendritic cells (DCs), as professional antigen-presenting cells, are members of the innate immune system and function as key players during the induction phase of adaptive immune responses. Uptake, processing, and presentation of antigens direct the outcome toward either tolerance or immunity. The cells of the immune system are among the most highly radiosensitive cells in the body. For high doses of ionizing radiation (HD-IR) both immune-suppressive effects after whole body irradiation and possible immune activation during tumor therapy were observed. On the other hand, the effects of low doses of ionizing radiation (LD-IR) on the immune system are controversial and seem to show high variability among different individuals and species. There are reports revealing that protracted LD-IR can result in radioresistance. But immune-suppressive effects of chronic LD-IR are also reported, including the killing or sensitizing of certain cell types. This article shall review the current knowledge of radiation-induced effects on the immune system, paying special attention to the interaction of DCs and T cells.
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Affiliation(s)
- Katrin Manda
- Department of Radiotherapy and Radiation Oncology, University of Rostock Rostock, Germany
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Abstract
PURPOSE To review the cellular mechanisms of hormetic effects induced by low dose and low dose rate ionising radiation in model systems, and to call attention to the possible role of autophagy in some hormetic effects. RESULTS AND CONCLUSIONS Very low radiation doses stimulate cell proliferation by changing the equilibrium between the phosphorylated and dephosphorylated forms of growth factor receptors. Radioadaptation is induced by various weak stress stimuli and depends on signalling events that ultimately decrease the molecular damage expression at the cellular level upon subsequent exposure to a moderate radiation dose. Ageing and cancer result from oxidative damage under oxidative stress conditions; nevertheless, ROS are also prominent inducers of autophagy, a cellular process that has been shown to be related both to ageing retardation and cancer prevention. A balance between the signalling functions and damaging effects of ROS seems to be the most important factor that decides the fate of the mammalian cell when under oxidative stress conditions, after exposure to ionising radiation. Not enough is yet known on the pre-requirements for maintaining such a balance. Given the present stage of investigation into radiation hormesis, the application of the conclusions from experiments on model systems to the radiation protection regulations would not be justified.
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Affiliation(s)
- Irena Szumiel
- Centre for Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warsaw, Poland.
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26
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Mozdarani H. Biological complexities in radiation carcinogenesis and cancer radiotherapy: impact of new biological paradigms. Genes (Basel) 2012; 3:90-114. [PMID: 24704845 PMCID: PMC3899963 DOI: 10.3390/genes3010090] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2011] [Revised: 01/07/2012] [Accepted: 01/13/2012] [Indexed: 12/31/2022] Open
Abstract
Although radiation carcinogenesis has been shown both experimentally and epidemiologically, the use of ionizing radiation is also one of the major modalities in cancer treatment. Various known cellular and molecular events are involved in carcinogenesis. Apart from the known phenomena, there could be implications for carcinogenesis and cancer prevention due to other biological processes such as the bystander effect, the abscopal effect, intrinsic radiosensitivity and radioadaptation. Bystander effects have consequences for mutation initiated cancer paradigms of radiation carcinogenesis, which provide the mechanistic justification for low-dose risk estimates. The abscopal effect is potentially important for tumor control and is mediated through cytokines and/or the immune system (mainly cell-mediated immunity). It results from loss of growth and stimulatory and/or immunosuppressive factors from the tumor. Intrinsic radiosensitivity is a feature of some cancer prone chromosomal breakage syndromes such as ataxia telangectiasia. Radiosensitivity is manifested as higher chromosomal aberrations and DNA repair impairment is now known as a good biomarker for breast cancer screening and prediction of prognosis. However, it is not yet known whether this effect is good or bad for those receiving radiation or radiomimetic agents for treatment. Radiation hormesis is another major concern for carcinogenesis. This process which protects cells from higher doses of radiation or radio mimic chemicals, may lead to the escape of cells from mitotic death or apoptosis and put cells with a lower amount of damage into the process of cancer induction. Therefore, any of these biological phenomena could have impact on another process giving rise to genome instability of cells which are not in the field of radiation but still receiving a lower amount of radiation. For prevention of radiation induced carcinogenesis or risk assessment as well as for successful radiation therapy, all these phenomena should be taken into account.
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Affiliation(s)
- Hossein Mozdarani
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran P.O. Box 14115-111, Iran.
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27
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Abstract
Today's radiation safety norms are based on the linear no-threshold theory (LNT): extrapolation of the dose-response relationships down to the minimal doses, where such relationships are unproven and can be inverse due to hormesis. The most promising way to obtaining reliable data on the dose-effect relationships for low radiation doses would be large-scale animal experiments. Outstanding published data on carcinogenic effects of the doses e.g. below 100 mSv should be verified by experiments. Arguments against applicability of the LNT to the doses comparable to those from the natural radiation background are discussed. Furthermore it is stressed that medical consequences of the Chernobyl accident have been overestimated; and this theme has been exploited to strangle development of atomic energy and to elevate prices for fossil fuels. Worldwide introduction of nuclear energy will be possible only after a concentration of authority within a powerful international executive. It would enable the construction of nuclear reactors in optimally suitable places, considering all sociopolitical, geographical, and geological conditions, which would contribute to the prevention of accidents like in Japan in 2011. A concluding point is that radiation safety norms are exceedingly restrictive and should be revised to become more realistic and workable. Elevation of the limits must be accompanied by measures guaranteeing their strict observance. It is also concluded that there are no evidence-based contraindications to fivefold elevation of the total equivalent effective doses to individual members of the public (up to 5 mSv/year), and doubling of the limits for professional exposures.
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Affiliation(s)
- SV Jargin
- Peoples’ Friendship University of Russia, Moscow, Russian Federation
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Sagai M, Bocci V. Mechanisms of Action Involved in Ozone Therapy: Is healing induced via a mild oxidative stress? Med Gas Res 2011; 1:29. [PMID: 22185664 PMCID: PMC3298518 DOI: 10.1186/2045-9912-1-29] [Citation(s) in RCA: 171] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Accepted: 12/20/2011] [Indexed: 01/06/2023] Open
Abstract
The potential mechanisms of action of ozone therapy are reviewed in this paper. The therapeutic efficacy of ozone therapy may be partly due the controlled and moderate oxidative stress produced by the reactions of ozone with several biological components. The line between effectiveness and toxicity of ozone may be dependent on the strength of the oxidative stress. As with exercise, it is well known that moderate exercise is good for health, whereas excessive exercise is not.Severe oxidative stress activates nuclear transcriptional factor kappa B (NFκB), resulting in an inflammatory response and tissue injury via the production of COX2, PGE2, and cytokines. However, moderate oxidative stress activates another nuclear transcriptional factor, nuclear factor-erythroid 2-related factor 2 (Nrf2). Nrf2 then induces the transcription of antioxidant response elements (ARE). Transcription of ARE results in the production of numerous antioxidant enzymes, such as SOD, GPx, glutathione-s-transferase(GSTr), catalase (CAT), heme-oxygenase-1 (HO-1), NADPH-quinone-oxidoreductase (NQO-1), phase II enzymes of drug metabolism and heat shock proteins (HSP). Both free antioxidants and anti-oxidative enzymes not only protect cells from oxidation and inflammation but they may be able to reverse the chronic oxidative stress. Based on these observations, ozone therapy may also activate Nrf2 via moderate oxidative stress, and suppress NFκB and inflammatory responses. Furthermore, activation of Nrf2 results in protection against neurodegenerative diseases, such as Alzheimer's and Parkinson's diseases. Mild immune responses are induced via other nuclear transcriptional factors, such as nuclear factor of activated T-cells (NFAT) and activated protein-1 (AP-1).Additionally, the effectiveness of ozone therapy in vascular diseases may also be explained by the activation of another nuclear transcriptional factor, hypoxia inducible factor-1α (HIF-1a), which is also induced via moderate oxidative stress. Recently these concepts have become widely accepted. The versatility of ozone in treating vascular and degenerative diseases as well as skin lesions, hernial disc and primary root carious lesions in children is emphasized. Further researches able to elucidate whether the mechanisms of action of ozone therapy involve nuclear transcription factors, such as Nrf2, NFAT, AP-1, and HIF-1α are warranted.
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Affiliation(s)
- Masaru Sagai
- Department of Physiology, Viale A, Moro 2, 53100, University of Siena, Italy.
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