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Bevelacqua JJ, Mortazavi SAR, Mortazavi SMJ, Welsh J. Professor John Roderick Cameron's Influence on Radiation Safety in Terrestrial and Space Environments. J Biomed Phys Eng 2024; 14:319-322. [PMID: 39027714 PMCID: PMC11252544 DOI: 10.31661/jbpe.v0i0.2405-1767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Accepted: 05/26/2024] [Indexed: 07/20/2024]
Abstract
Professor John Roderick Cameron (1922-2005) stands out as a trailblazer in the field of medical physics, whose innovative work has deeply influenced radiation protection and the broader medical radiation field through sound technical judgment and insight. Best known for inventing the bone densitometry device, his pioneering efforts have reshaped modern medical practices far beyond his initial breakthroughs. Cameron's explorations extended into the realms of space biomedical science and models of terrestrial radiation, areas where his insights continue to resonate today. As the Emeritus Professor of Medical Physics at the University of Wisconsin-Madison and a founding member of the American Association of Physicists in Medicine, Cameron laid crucial groundwork for safety standards in environments with high natural radiation levels. His leadership was instrumental in advancing thermoluminescence dosimetry, radiation measurement, and image quality assurance, driving progress in both academia and clinical practices. Moreover, through establishing Medical Physics Publishing, Cameron played a pivotal role in spreading vital research and educational materials across the fields of health physics and medical physics. This commentary reflects on Cameron's far-reaching contributions, highlighting his critical work in space radiation research and terrestrial radiation models-key to the future of interplanetary travel and potential human settlement on planets like Mars. His research in areas of high background radiation, like Ramsar, Iran, has been fundamental in developing strategies for biological protection in space, which are essential for ensuring astronaut safety during long-duration space missions. We honor Professor Cameron's profound legacy, celebrating his visionary spirit and the lasting impact of his contributions on generations of scientists in radiation science.
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Affiliation(s)
| | | | - Seyed Mohammad Javad Mortazavi
- Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
- Department of Medical Physics and Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - James Welsh
- Department of Radiation Oncology, Edward Hines Jr VA Hospital, Hines, IL, United States
- Department of Radiation Oncology, Stritch School of Medicine, Loyola University, Chicago, IL, United States
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Mortazavi A, Mortazavi SMJ. Cameron's impact on space biomedical sciences-expanding insights to Ng and Doi's article. Radiol Phys Technol 2024; 17:578-579. [PMID: 38607477 DOI: 10.1007/s12194-024-00801-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 04/13/2024]
Affiliation(s)
| | - S M J Mortazavi
- Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
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Masoudi S, Kalani M, Alavianmehr A, Mosleh-Shirazi MA, Mortazavi SMJ, Farjadian S. Sequential radiation exposure: uncovering the potential of low dose ionizing radiation in mitigating high dose effects on immune cells. Int J Radiat Biol 2024; 100:1009-1018. [PMID: 38776451 DOI: 10.1080/09553002.2024.2345107] [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: 09/18/2023] [Accepted: 04/09/2024] [Indexed: 05/25/2024]
Abstract
PURPOSE The radioadaptive response refers to a phenomenon wherein exposure to a low dose of ionizing radiation (LDIR) can induce a protective response in cells or organisms, reducing the adverse effects of a subsequent higher dose of ionizing radiation (HDIR). However, it is possible to administer the low dose after the challenge dose. This study was conducted to determine the potential mitigating effect of LDIR administered after HDIR on mice immune cells. MATERIALS AND METHODS Alongside the conventional adaptive response setting, one group of mice was initially exposed to HDIR and subsequently treated with LDIR. Neutrophil activation was done using DHR-reducing assay and cell proliferation was evaluated through CFSE-dilution assay in helper (CD4+) and cytotoxic (CD8+) T cells. Cytokine production by these T cell subsets was also assessed by intracellular staining using flow cytometry. RESULTS The results of this study revealed no change in neutrophil function between any of the mice groups compared to the untreated control group. Although significant changes were not detected in the proliferation of CD4+ T cells, decreased proliferation was observed in stimulated CD8+ T cells in the HDIR group. In contrast to IFN-ɣ, which showed no evident change in either of the T cell subsets after stimulation, IL-4 was rigorously dropped in stimulated CD4+ T cells in the HDIR group. CONCLUSIONS In summary, the results of this study indicated that the administration of LDIR to mice before HDIR was not able to reduce the detrimental effects of HDIR in our experimental setting. Instead, we observed a mitigating effect of LDIR when administered after the challenge dose. This suggests that not only the dose and duration but also the order of LDIR relative to HDIR affects its efficacy.
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Affiliation(s)
- Sadegh Masoudi
- The Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mehdi Kalani
- Professor Alborzi Clinical Microbiology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ali Alavianmehr
- Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohammad Amin Mosleh-Shirazi
- The Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
- Radiotherapy Department and Center for Research in Medical Physics and Biomedical Engineering, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyed Mohammad Javad Mortazavi
- The Ionizing and Non-Ionizing Radiation Protection Research Center (INIRPRC), School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
- Department of Medical Physics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Shirin Farjadian
- Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Mortazavi SMJ, Said-Salman I, Mortazavi AR, El Khatib S, Sihver L. How the adaptation of the human microbiome to harsh space environment can determine the chances of success for a space mission to Mars and beyond. Front Microbiol 2024; 14:1237564. [PMID: 38390219 PMCID: PMC10881706 DOI: 10.3389/fmicb.2023.1237564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Accepted: 12/05/2023] [Indexed: 02/24/2024] Open
Abstract
The ability of human cells to adapt to space radiation is essential for the well-being of astronauts during long-distance space expeditions, such as voyages to Mars or other deep space destinations. However, the adaptation of the microbiomes should not be overlooked. Microorganisms inside an astronaut's body, or inside the space station or other spacecraft, will also be exposed to radiation, which may induce resistance to antibiotics, UV, heat, desiccation, and other life-threatening factors. Therefore, it is essential to consider the potential effects of radiation not only on humans but also on their microbiomes to develop effective risk reduction strategies for space missions. Studying the human microbiome in space missions can have several potential benefits, including but not limited to a better understanding of the major effects space travel has on human health, developing new technologies for monitoring health and developing new radiation therapies and treatments. While radioadaptive response in astronauts' cells can lead to resistance against high levels of space radiation, radioadaptive response in their microbiome can lead to resistance against UV, heat, desiccation, antibiotics, and radiation. As astronauts and their microbiomes compete to adapt to the space environment. The microorganisms may emerge as the winners, leading to life-threatening situations due to lethal infections. Therefore, understanding the magnitude of the adaptation of microorganisms before launching a space mission is crucial to be able to develop effective strategies to mitigate the risks associated with radiation exposure. Ensuring the safety and well-being of astronauts during long-duration space missions and minimizing the risks linked with radiation exposure can be achieved by adopting this approach.
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Affiliation(s)
- Seyed Mohammad Javad Mortazavi
- Ionizing and non-ionizing radiation protection research center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ilham Said-Salman
- Department of Biological and Chemical Sciences, School of Arts & Sciences, Lebanese International University, Saida, Lebanon
- Department of Biological and Chemical Sciences, International University of Beirut, Beirut, Lebanon
| | | | - Sami El Khatib
- Department of Biomedical Sciences, School of Arts and Sciences, Lebanese International University, Beirut, Lebanon
- Center for Applied Mathematics and Bioinformatics (CAMB) at Gulf University for Science and Technology, Kuwait City, Kuwait
| | - Lembit Sihver
- Department of Radiation Dosimetry, Nuclear Physics Institute (NPI) of the Czech Academy of Sciences (CAS), Prague, Czechia
- Department of Radiation Physics, Technische Universität Wien Atominstitut, Vienna, Austria
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Mortazavi SA, Haghani M, Vafapour H, Ghadimi-Moghadam A, Yarbakhsh H, Eslami J, Yarbakhsh R, Zarei S, Rastegarian N, Shams SF, Darvish L, Mohammadi S. Should Parents Allow Their Children Use Smartphones and Tablets? The Issue of Screen Time for Recreational Activities. J Biomed Phys Eng 2023; 13:563-572. [PMID: 38148959 PMCID: PMC10749417 DOI: 10.31661/jbpe.v0i0.535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 08/23/2019] [Indexed: 12/28/2023]
Abstract
Previous research has shown that children are more vulnerable to the adverse effects of radiofrequency electromagnetic fields (RF-EMFs) and blue light emitted from digital screens compared to healthy adults. This paper presents the findings of a cross-sectional study conducted in Yasuj, Iran, to investigate the screen time habits of children and adolescents and its potential impact on their health. A total of 63 participants, including 44 boys and 19 girls, were randomly selected for the study. The results showed that the average daily screen time for the children was 87.38 minutes, with a standard deviation of 49.58. When examining the specific purposes of screen time, it was found that the children spent an average of 17.54 minutes per day on screens for school assignments, 70 minutes per day for recreational purposes, and 23.41 minutes per day for contacting family, friends, and relatives. Our study highlights that a significant portion of the children's screen time was allocated to recreational activities. We observed some differences in screen time between girls and boys. Boys had a slightly higher overall daily screen time, primarily driven by more recreational screen time. However, girls spent slightly more time on screens for school assignments. The screen time for social interactions was similar for both genders. Our findings on the cognitive performance of children with different levels of screen time will be published in a separate paper.
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Affiliation(s)
| | - Masoud Haghani
- Department of Radiology, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hassan Vafapour
- Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
| | | | - Helia Yarbakhsh
- Department of Nutrition Sciences, School of Nutrition and Food Sciences, Larestan University of Medical Sciences, Larestan, Iran
| | - Jamshid Eslami
- Department of Anesthesiology, School of Nursing & Midwifery, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Reza Yarbakhsh
- Department of Computer Engineering, Sharif University, Tehran, Iran
| | - Sina Zarei
- Student Research Committee, School of Rehabilitation, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Niloofar Rastegarian
- Department of Speech Pathology, School of Rehabilitation, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Seyedeh Fateme Shams
- Clinical Research Development Unit, Valiasr Hospital, Fasa University of Medical Sciences, Fasa, Iran
| | - Leili Darvish
- MVLS College, The University of Glasgow, Glasgow, Scotland, UK
| | - Sahar Mohammadi
- Department of Radiology, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
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Changes in Radiosensitivity to Gamma-Rays of Lymphocytes from Hyperthyroid Patients Treated with I-131. Int J Mol Sci 2022; 23:ijms231710156. [PMID: 36077557 PMCID: PMC9456272 DOI: 10.3390/ijms231710156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/17/2022] [Accepted: 08/27/2022] [Indexed: 11/17/2022] Open
Abstract
This study investigated the peripheral blood lymphocytes (PBL) response to a dose of γ-rays in patients treated with radioiodine (I-131) for hyperthyroidism vs. healthy controls, to gain information about the individual lymphocytes’ radio-sensitivity. Blood samples were taken from 18 patients and 10 healthy donors. Phosphorylated histone variant H2AX (γ-H2AX) and micronuclei (MN) induction were used to determine the change in PBL radio-sensitivity and the correlations between the two types of damage. The two assays showed large inter-individual variability in PBL background damage and in radio-sensitivity (patients vs. healthy donors). In particular, they showed an increased radio-sensitivity in 36% and 33% of patients, decrease in 36% and 44%, respectively. There was a scarce correlation between the two assays and no dependence on age or gender. A significant association was found between high radio-sensitivity conditions and induced hypothyroidism. PBL radio-sensitivity in the patient group was not significantly affected by treatment with I-131, whereas there were significant changes inter-individually. The association found between clinical response and PBL radio-sensitivity suggests that the latter could be used in view of the development of personalized treatments.
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Sihver L, Mortazavi SMJ. Biological Protection in Deep Space Missions. J Biomed Phys Eng 2021; 11:663-674. [PMID: 34904063 PMCID: PMC8649166 DOI: 10.31661/jbpe.v0i0.1193] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Accepted: 07/20/2019] [Indexed: 01/15/2023]
Abstract
During deep space missions, astronauts are exposed to highly ionizing radiation, incl. neutrons, protons and heavy ions from galactic cosmic rays (GCR), solar wind (SW) and solar energetic particles
(SEP). This increase the risks for cancerogenisis, damages in central nervous system (CNS), cardiovascular diseases, etc. Large SEP events can even cause acute radiation syndrome (ARS).
Long term manned deep space missions will therefor require unique radiation protection strategies. Since it has been shown that physical shielding alone is not sufficient, this paper
propose pre-flight screening of the aspirants for evaluation of their level of adaptive responses. Methods for boosting their immune system, should also be further investigated,
and the possibility of using radiation effect modulators are discussed. In this paper, especially, the use of vitamin C as a promising non-toxic, cost-effective, easily available
radiation mitigator (which can be used hours after irradiation), is described. Although it has previously been shown that vitamin C can decrease radiation-induced chromosomal damage in rodents,
it must be further investigated before any conclusions about its radiation mitigating properties in humans can be concluded.
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Affiliation(s)
- Lembit Sihver
- PhD, Department of Radiation Physics, Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Vienna, Austria
- PhD, Department of Physics, Chalmers University of Technology, 412 96 Gothenburg, Sweden
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Bevelacqua JJ, Mortazavi SMJ. Comments on 'DNA damage in blood leukocytes from mice irradiated with accelerated carbon ions with an energy of 450 MeV/nucleon'. Int J Radiat Biol 2021; 97:442-443. [PMID: 33539257 DOI: 10.1080/09553002.2021.1884313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
| | - S M J Mortazavi
- Medical Physics and Engineering Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Bevelacqua JJ, Welsh J, Mortazavi SAR, Keshavarz M, Mortazavi SMJ. Space Medicine: Why Do Recently Published Papers about Telomere Length Alterations Increase our Uncertainty Rather than Reduce it? J Biomed Phys Eng 2021; 11:103-108. [PMID: 33564645 PMCID: PMC7859374 DOI: 10.31661/jbpe.v0i0.2005-1115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2020] [Accepted: 07/27/2020] [Indexed: 11/16/2022]
Abstract
There is a growing interest in examining alterations in telomere length as a reliable biomarker of general health, as well as a marker for predicting later morbidity and mortality. Substantial evidence shows that telomere length is associated with aging; telomere shortening acts as a "counting mechanism" that drives replicative senescence by limiting the mitotic potential of normal (but not malignant) cells. In this Correspondence, we attempt to answer the question of why recently published papers about telomere length alterations increase our uncertainty rather than reduce it. This discussion includes three major research areas regarding telomere length: environmental stressors, aging, and life span. Our review suggests that activation of telomerase activity due to stressors in space might be a double-edged sword with both favorable and unfavorable consequences. The selection of an effect's consequence must clearly elucidate the experimental conditions as well as associated stressors. In this Correspondence, we attempt to answer the question of why recently published papers about telomere length alterations increase our uncertainty rather than reduce it. The selection of an effect's consequence must clearly elucidate the experimental conditions as well as associated stressors. Both positive and negative consequences must be clearly addressed in order to bolster the conclusions, as well as identify future research directions.
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Affiliation(s)
- J J Bevelacqua
- PhD, Bevelacqua Resources, Richland, Washington 99352, United States
| | - J Welsh
- MD, PhD, Loyola University Chicago, Edward Hines Jr., VA Hospital, Stritch School of Medicine, Department of Radiation Oncology, Maywood, IL 60153 USA
| | - S A R Mortazavi
- MD, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M Keshavarz
- MSc, Department of Medical Physics and Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S M J Mortazavi
- PhD, Department of Medical Physics and Engineering, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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Bevelacqua JJ, Mortazavi S. Comments on "Effects of partial- or whole-body exposures to 56Fe particles on brain function and cognitive performance in rats". LIFE SCIENCES IN SPACE RESEARCH 2020; 27:105-106. [PMID: 34756223 DOI: 10.1016/j.lssr.2020.08.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2020] [Revised: 08/22/2020] [Accepted: 08/25/2020] [Indexed: 06/13/2023]
Affiliation(s)
| | - Smj Mortazavi
- Medical Physics and Engineering Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran.
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Bevelacqua JJ, Welsh J, Mortazavi S. Comment on "Dexamethasone Inhibits Spheroid Formation of Thyroid Cancer Cells Exposed to Simulated Microgravity". Cells 2020; 9:cells9071738. [PMID: 32708131 PMCID: PMC7409090 DOI: 10.3390/cells9071738] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Revised: 05/27/2020] [Accepted: 07/13/2020] [Indexed: 02/08/2023] Open
Affiliation(s)
| | - James Welsh
- Department of Radiation Oncology, Edward Hines Jr VA Hospital, Hines, IL 60141, USA;
| | - S.M.J. Mortazavi
- Diagnostic Imaging Department, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
- Correspondence: ; Tel.: +1-(215)-214-1769
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J J B, S M J M. Poor Understanding of Radiation Profiles in Deep Space Causes Inaccurate Findings and Misleading Conclusions. J Biomed Phys Eng 2019; 9:587-588. [PMID: 31750273 PMCID: PMC6820022 DOI: 10.31661/jbpe.v0i0.1021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Accepted: 10/20/2018] [Indexed: 11/16/2022]
Abstract
The radiation environment in deep space, where astronauts are behind the shelter provided by the Earth's magnetosphere, is a major health concern. Galactic cosmic rays (GCR) and solar particle events (SPE) are two basic sources of space radiation in the solar system. The health risks of exposure to high levels of space radiation can be observed either as acute and delayed effects. Zhang et al. in their recently published paper entitled "γ-H2AX responds to DNA damage induced by long-term exposure to combined low-dose-rate neutron and γ-ray radiation" have addressed the effects of different cumulative radiation doses on peripheral blood cell, subsets of T cells of peripheral blood lymphocytes and DNA damage repair. These researchers exposed animals to low dose rate 60Co-rays at 0.0167 Gy h-1for 2 h/d and 252Cf neutrons at 0.028 mGy h-1for 20 h/d for 15, 30, or 60 consecutive days. They reported that the mRNA of H2AX increased significantly, and showed a positive correlation with dose. Despite strengths, this paper has several shortcomings such as poor definition of low dose radiation as well as space and reactor radiation environments. Another shortcoming of this paper comes from this point that blood cell studies do not represent the biological effects of ionizing radiation on the total body. Moreover, the effects of the human immune system and DNA repair mechanisms are not included in the study. The role of pre-exposures and induction of adaptive response phenomena in decreasing the risk of radiation in deep space missions are also ignored.
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Affiliation(s)
- Bevelacqua J J
- PhD,Bevelacqua Resources, 343 Adair Drive, Richland, WA 99352, USA
| | - Mortazavi S M J
- PhD,Medical Physics Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- PhD, Diagnostic Imaging Department, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
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J W, J J B, M K, S A R M, S M J M. Is Telomere Length a Biomarker of Adaptive Response in Space? Curious Findings from NASA and Residents of High Background Radiation Areas. J Biomed Phys Eng 2019; 9:381-388. [PMID: 31341884 PMCID: PMC6613149 DOI: 10.31661/jbpe.v9i3jun.1151] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 04/07/2019] [Indexed: 01/18/2023]
Abstract
Telomere length and stability is a biomarker of aging, stress, and cancer. Shortening of telomeres and high level of DNA damages are known to be associated with aging. Telomere shortening normally occurs during cell division in most cells and when telomeres reach a critically short length, DNA damage signaling and cellular senescence can be triggered. The induction of an adaptive response by space radiation was first documented in 2003. Telomere length alterations are among the most fascinating observations in astronauts and residents of high background radiation areas. While study of the chronic exposure to high levels of background ionizing radiation in Kerala, India failed to show a significant influence on telomere length, limited data about the NASA astronaut Scott Kelly show that exposure to space radiation can induce telomeres to regain length. Interestingly, his telomeres shortened again only a couple of days after returning to Earth. The difference between these situations may be due to the differences in radiation dose, dose-rate, and/or type of radiation. Moreover, Scott Kelly’s spacewalks (EVA) could have significantly increased his cumulative radiation dose. It is worth noting that the spacewalks not only confer a higher dose activity but are also characterized by a different radiation spectrum than inside the space craft since the primary particles would not interact with the vehicle shell to generate secondary radiation. Generally, these differences can possibly indicate the necessity of a minimum dose/dose-rate for induction of adaptive response (the so called Window effect).
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Affiliation(s)
- Welsh J
- Department of Radiation Oncology, Edward Hines Jr VA Hospital, Hines, IL 60141, United States
| | - Bevelacqua J J
- Bevelacqua Resources, Richland, Washington 99352, United States
| | - Keshavarz M
- Department of Medical Physics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mortazavi S A R
- School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mortazavi S M J
- Department of Medical Physics, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
- Diagnostic Imaging Department, Fox Chase Cancer Center, Philadelphia, Pennsylvania 19111, United States
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Acquired Antibiotic Resistance in Escherichia coli Exposed to Simulated Microgravity: Possible Role of Other Space Stressors and Adaptive Responses. mBio 2019; 10:mBio.00165-19. [PMID: 30914503 PMCID: PMC6437047 DOI: 10.1128/mbio.00165-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Bevelacqua JJ, Mortazavi SMJ. Commentary regarding "on-orbit sleep problems of astronauts and countermeasures". Mil Med Res 2018; 5:38. [PMID: 30376883 PMCID: PMC6208067 DOI: 10.1186/s40779-018-0185-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/11/2018] [Indexed: 02/02/2023] Open
Abstract
This commentary addresses the article by Wu et al. entitled "On-orbit sleep problems of astronauts and countermeasures". In this article, the authors discussed the sleep problems of astronauts. Despite its challenging topic, the paper authored by Wu et al. has at least one major shortcoming. This issue is related to the observation that the sleep pattern of astronauts can be disturbed by light flash phenomenon. Since the first report by astronaut E.E. Aldrin in 1969, many astronauts have reported light flashes. These visually perceived flashes of light occurred in different shapes but they apparently moved across the visual field of astronauts and possibly caused, at least to some extent, sleep problems. Moreover, the countermeasures proposed by the authors may improve astronauts' sleep pattern, but they do not address the root cause of the light flashes (i.e., heavy ion interactions outside the shielding provided by the Earth's magnetosphere). A possible approach to reducing light flashes is available using the fact that much of the galactic cosmic radiation (GCR) spectrum is composed of ions that can be diverted from the spacecraft using electromagnetic fields. Possible design parameters and the requisite electric and magnetic field strengths to successfully deflect GCR radiation are outlined.
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Affiliation(s)
| | - Seyed Mohammad Javad Mortazavi
- Department of Electrical Engineering, Biophotonics Lab, University of Wisconsin Milwaukee, 3200 N Cramer St, Milwaukee, WI53211, USA. .,Doss Lab (R-432), Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA19111, USA.
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Takahashi A, Ikeda H, Yoshida Y. Role of High-Linear Energy Transfer Radiobiology in Space Radiation Exposure Risks. Int J Part Ther 2018; 5:151-159. [PMID: 31773027 DOI: 10.14338/ijpt-18-00013.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 06/21/2018] [Indexed: 01/17/2023] Open
Abstract
Many manned missions to the Moon and Mars are scheduled in the near future. However, space radiation presents a major hazard to humans, and astronauts are constantly exposed to radiation, including high linear energy transfer (LET) radiation, which differs from radiation on Earth. Thus, there is thus an urgent need to clarify the biological effects of space radiation and reduce the associated risks. In this review, we consider the role of high-LET radiobiology in relation to space-radiation exposure.
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Affiliation(s)
| | - Hiroko Ikeda
- Gunma University Initiative for Advanced Research, Maebashi, Gunma, Japan
| | - Yukari Yoshida
- Gunma University Heavy Ion Medical Center, Maebashi, Gunma, Japan
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Bevelacqua JJ, Mortazavi SMJ. Commentary: Immune System Dysregulation During Spaceflight: Potential Countermeasures for Deep Space Exploration Missions. Front Immunol 2018; 9:2024. [PMID: 30233600 PMCID: PMC6131484 DOI: 10.3389/fimmu.2018.02024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 08/16/2018] [Indexed: 01/02/2023] Open
Affiliation(s)
| | - S M J Mortazavi
- Diagnostic Imaging Department, Fox Chase Cancer Center, Philadelphia, PA, United States.,INIRPRC, Shiraz University of Medical Sciences, Shiraz, Iran
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Bevelacqua JJ, Mortazavi SMJ. Commentary regarding: "The effect of simulated space radiation on the N-glycosylation of human immunoglobulin G1". Electrophoresis 2018; 39:2848-2850. [PMID: 29947428 DOI: 10.1002/elps.201800216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 06/11/2018] [Indexed: 11/10/2022]
Abstract
Deep space missions, including Mars voyages, are an important area of research. Protection of astronauts' health during these long-term missions is of paramount importance. The paper authored by Szarka et al. entitled "The effect of simulated space radiation on the N-glycosylation of human immunoglobulin G1" is indeed a step forward in this effort. Despite numerous strengths, there are some shortcomings in this paper including an incomplete description of the space radiation environment as well as discussion of the resulting biological effects. Due to complexity of the space radiation environment, a careful analysis is needed to fully evaluate the spectrum of particles associated with solar particle events and galactic cosmic radiation. The radiation source used in this experiment does not reproduce the range of primary galactic cosmic radiation and solar particle events particles and their associated energies. Furthermore, the effect of radiation interactions within the spacecraft shell and the potential effects of microgravity are not considered. Moreover, the importance of radioadaptation in deep space missions that is confirmed in a NASA report is neither considered. Other shortcomings are also discussed in this commentary. Considering these shortcomings, it can be argued that Szarka et al. draw conclusions based on an incomplete description of the space radiation environment that could affect the applicability of this study.
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Affiliation(s)
| | - S M J Mortazavi
- Biophotonics Lab, Department of Electrical Engineering, University of Wisconsin Milwaukee, Milwaukee, WI, USA.,Ionizing and Non-ionizing Radiation Protection Research Center (INIRPRC), Shiraz University of Medical Sciences, Shiraz, Iran
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Cortese F, Klokov D, Osipov A, Stefaniak J, Moskalev A, Schastnaya J, Cantor C, Aliper A, Mamoshina P, Ushakov I, Sapetsky A, Vanhaelen Q, Alchinova I, Karganov M, Kovalchuk O, Wilkins R, Shtemberg A, Moreels M, Baatout S, Izumchenko E, de Magalhães JP, Artemov AV, Costes SV, Beheshti A, Mao XW, Pecaut MJ, Kaminskiy D, Ozerov IV, Scheibye-Knudsen M, Zhavoronkov A. Vive la radiorésistance!: converging research in radiobiology and biogerontology to enhance human radioresistance for deep space exploration and colonization. Oncotarget 2018; 9:14692-14722. [PMID: 29581875 PMCID: PMC5865701 DOI: 10.18632/oncotarget.24461] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/31/2018] [Indexed: 12/12/2022] Open
Abstract
While many efforts have been made to pave the way toward human space colonization, little consideration has been given to the methods of protecting spacefarers against harsh cosmic and local radioactive environments and the high costs associated with protection from the deleterious physiological effects of exposure to high-Linear energy transfer (high-LET) radiation. Herein, we lay the foundations of a roadmap toward enhancing human radioresistance for the purposes of deep space colonization and exploration. We outline future research directions toward the goal of enhancing human radioresistance, including upregulation of endogenous repair and radioprotective mechanisms, possible leeways into gene therapy in order to enhance radioresistance via the translation of exogenous and engineered DNA repair and radioprotective mechanisms, the substitution of organic molecules with fortified isoforms, and methods of slowing metabolic activity while preserving cognitive function. We conclude by presenting the known associations between radioresistance and longevity, and articulating the position that enhancing human radioresistance is likely to extend the healthspan of human spacefarers as well.
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Affiliation(s)
- Franco Cortese
- Biogerontology Research Foundation, London, UK
- Department of Biomedical and Molecular Sciences, Queen's University School of Medicine, Queen's University, Kingston, Ontario, Canada
| | - Dmitry Klokov
- Canadian Nuclear Laboratories, Chalk River, Ontario, Canada
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
| | - Andreyan Osipov
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow, Russia
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia
| | - Jakub Stefaniak
- Biogerontology Research Foundation, London, UK
- Nuffield Department of Medicine, Target Discovery Institute, University of Oxford, Oxford, UK
| | - Alexey Moskalev
- Moscow Institute of Physics and Technology, Dolgoprudny, Russia
- Laboratory of Molecular Radiobiology and Gerontology, Institute of Biology of Komi Science Center of Ural Branch of Russian Academy of Sciences, Syktyvkar, Russia
- Engelhardt Institute of Molecular Biology of Russian Academy of Sciences, Moscow, Russia
| | - Jane Schastnaya
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
| | - Charles Cantor
- Boston University, Department of Biomedical Engineering, Boston, MA, USA
| | - Alexander Aliper
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
- Laboratory of Bioinformatics, D. Rogachev Federal Medical Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
| | - Polina Mamoshina
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
- Computer Science Department, University of Oxford, Oxford, UK
| | - Igor Ushakov
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow, Russia
| | - Alex Sapetsky
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow, Russia
| | - Quentin Vanhaelen
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
| | - Irina Alchinova
- Laboratory of Physicochemical and Ecological Pathophysiology, Institute of General Pathology and Pathophysiology, Moscow, Russia
- Research Institute for Space Medicine, Federal Medical Biological Agency, Moscow, Russia
| | - Mikhail Karganov
- Laboratory of Physicochemical and Ecological Pathophysiology, Institute of General Pathology and Pathophysiology, Moscow, Russia
| | - Olga Kovalchuk
- Canada Cancer and Aging Research Laboratories, Ltd., Lethbridge, Alberta, Canada
- University of Lethbridge, Lethbridge, Alberta, Canada
| | - Ruth Wilkins
- Environmental and Radiation and Health Sciences Directorate, Health Canada, Ottawa, Ontario, Canada
| | - Andrey Shtemberg
- Laboratory of Extreme Physiology, Institute of Medical and Biological Problems RAS, Moscow, Russia
| | - Marjan Moreels
- Radiobiology Unit, Interdisciplinary Biosciences, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, (SCK·CEN), Mol, Belgium
| | - Sarah Baatout
- Radiobiology Unit, Interdisciplinary Biosciences, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre, (SCK·CEN), Mol, Belgium
- Department of Molecular Biotechnology, Ghent University, Ghent, Belgium
| | - Evgeny Izumchenko
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
- The Johns Hopkins University, School of Medicine, Department of Otolaryngology, Head and Neck Cancer Research, Baltimore, MD, USA
| | - João Pedro de Magalhães
- Biogerontology Research Foundation, London, UK
- Integrative Genomics of Ageing Group, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool, UK
| | - Artem V. Artemov
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
| | | | - Afshin Beheshti
- Wyle Laboratories, Space Biosciences Division, NASA Ames Research Center, Mountain View, CA, USA
- Division of Hematology/Oncology, Molecular Oncology Research Institute, Tufts Medical Center, Boston, MA, USA
| | - Xiao Wen Mao
- Department of Basic Sciences, Division of Biomedical Engineering Sciences (BMES), Loma Linda University, Loma Linda, CA, USA
| | - Michael J. Pecaut
- Department of Basic Sciences, Division of Biomedical Engineering Sciences (BMES), Loma Linda University, Loma Linda, CA, USA
| | - Dmitry Kaminskiy
- Biogerontology Research Foundation, London, UK
- Deep Knowledge Life Sciences, London, UK
| | - Ivan V. Ozerov
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
- State Research Center - Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency, Moscow, Russia
| | | | - Alex Zhavoronkov
- Biogerontology Research Foundation, London, UK
- Insilico Medicine, Inc., Emerging Technology Centers, Johns Hopkins University, Baltimore, MD, USA
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Bevelacqua JJ, Welsh J, Mortazavi SMJ. Comments on 'An overview of space medicine'. Br J Anaesth 2018; 120:874-876. [PMID: 29576129 DOI: 10.1016/j.bja.2017.12.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 12/09/2017] [Accepted: 12/10/2017] [Indexed: 01/02/2023] Open
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Bevelacqua JJ, Mortazavi S. Commentary: Human Pathophysiological Adaptations to the Space Environment. Front Physiol 2018; 8:1116. [PMID: 29358922 PMCID: PMC5766677 DOI: 10.3389/fphys.2017.01116] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Accepted: 12/18/2017] [Indexed: 12/18/2022] Open
Affiliation(s)
| | - S.M.J. Mortazavi
- Diagnostic Imaging Center, Fox Chase Cancer Center, Philadelphia, PA, United States
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Mortazavi SMJ. Comments on "Incidence of cancer among licensed commercial pilots flying North Atlantic routes". Environ Health 2017; 16:125. [PMID: 29149894 PMCID: PMC5693704 DOI: 10.1186/s12940-017-0333-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 11/01/2017] [Indexed: 06/07/2023]
Abstract
Gudmundsdottir et al. in their paper entitled "Incidence of cancer among licensed commercial pilots flying North Atlantic routes" published in Environmental Health have evaluated the effects of exposure to higher levels of cosmic radiation on cancer incidence in the pilots of commercial flights. Despite its remarkable strengths, the paper authored by Gudmundsdottir et al. has some shortcomings. The shortcomings of this paper such as not determining the shape of dose-response relationship for radiation-induced cancers, limitations in flight dose calculations, the weaknesses of CARI-6 as the program used by Gudmundsdottir et al. to estimate the effective dose of galactic cosmic rays, and the problems associated with unpredictable nature of the magnitude and duration of solar particle events are discussed.
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Affiliation(s)
- S M J Mortazavi
- Diagnostic Imaging Center, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA, 19111, USA.
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Deng C, Wang T, Wu J, Xu W, Li H, Liu M, Wu L, Lu J, Bian P. Effect of modeled microgravity on radiation-induced adaptive response of root growth in Arabidopsis thaliana. Mutat Res 2017; 796:20-28. [PMID: 28254518 DOI: 10.1016/j.mrfmmm.2017.02.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Revised: 02/05/2017] [Accepted: 02/10/2017] [Indexed: 06/06/2023]
Abstract
Space particles have an inevitable impact on organisms during space missions; radio-adaptive response (RAR) is a critical radiation effect due to both low-dose background and sudden high-dose radiation exposure during solar storms. Although it is relevant to consider RAR within the context of microgravity, another major space environmental factor, there is no existing evidence as to its effects on RAR. In the present study, we established an experimental method for detecting the effects of gamma-irradiation on the primary root growth of Arabidopsis thaliana, in which RAR of root growth was significantly induced by several dose combinations. Microgravity was simulated using a two-dimensional rotation clinostat. It was shown that RAR of root growth was significantly inhibited under the modeled microgravity condition, and was absent in pgm-1 plants that had impaired gravity sensing in root tips. These results suggest that RAR could be modulated in microgravity. Time course analysis showed that microgravity affected either the development of radio-resistance induced by priming irradiation, or the responses of plants to challenging irradiation. After treatment with the modeled microgravity, attenuation in priming irradiation-induced expressions of DNA repair genes (AtKu70 and AtRAD54), and reduced DNA repair efficiency in response to challenging irradiation were observed. In plant roots, the polar transportation of the phytohormone auxin is regulated by gravity, and treatment with an exogenous auxin (indole-3-acetic acid) prevented the induction of RAR of root growth, suggesting that auxin might play a regulatory role in the interaction between microgravity and RAR of root growth.
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Affiliation(s)
- Chenguang Deng
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, PR China; Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, PR China; Institute of Technical Biology and Agriculture Engineering, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, PR China; University of Science and Technology of China, Hefei 230026, PR China
| | - Ting Wang
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, PR China; Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, PR China; Institute of Technical Biology and Agriculture Engineering, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, PR China
| | - Jingjing Wu
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, PR China; Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, PR China; Institute of Technical Biology and Agriculture Engineering, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, PR China; University of Science and Technology of China, Hefei 230026, PR China
| | - Wei Xu
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, PR China; Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, PR China; Institute of Technical Biology and Agriculture Engineering, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, PR China
| | - Huasheng Li
- China Space Molecular Biological Lab, China Academy of Space Technology, Beijing 100086, PR China
| | - Min Liu
- China Space Molecular Biological Lab, China Academy of Space Technology, Beijing 100086, PR China
| | - Lijun Wu
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, PR China; Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, PR China; Institute of Technical Biology and Agriculture Engineering, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, PR China
| | - Jinying Lu
- China Space Molecular Biological Lab, China Academy of Space Technology, Beijing 100086, PR China.
| | - Po Bian
- Key Laboratory of Ion Beam Bioengineering, Hefei Institutes of Physical Science, Chinese Academy of Sciences, PR China; Key Laboratory of Environmental Toxicology and Pollution Control Technology of Anhui Province, PR China; Institute of Technical Biology and Agriculture Engineering, Chinese Academy of Sciences, 350 Shushanhu Road, Hefei 230031, PR China.
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24
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Alavi M, Taeb S, Okhovat MA, Atefi M, Negahdari F. Look Different: Effect of Radiation Hormesis on the Survival Rate of Immunosuppressed Mice. J Biomed Phys Eng 2016; 6:139-146. [PMID: 27853721 PMCID: PMC5106546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 01/12/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Hormesis is defined as the bio-positive response of something which is bio-negative in high doses. In the present study, the effect of radiation hormesis was evaluated on the survival rate of immunosuppressed BALB/c mice by Cyclosporine A. MATERIAL AND METHODS We used 75 consanguine, male, BALB/c mice in this experiment. The first group received Technetium-99m and the second group was placed on a sample radioactive soil of Ramsar region (800Bq) for 20 days. The third group was exposed to X-rays and the fourth group was placed on the radioactive soil and then injected Technetium-99m. The last group was the sham irradiated control group. Finally, 30mg Cyclosporine A as the immunosuppressive agent was orally administered to all mice 48 hours after receiving X-rays and Technetium-99m. The mean survival rate of mice in each group was estimated during time. RESULTS A log rank test was run to determine if there were differences in the survival distribution for different groups and related treatments. According to the results, the survival rate of all pre-irradiated groups was more than the sham irradiated control group (p < .05). The highest survival time was related to the mice which were placed on the radioactive soil of Ramsar region for 20 days and then injected Technetium-99m. CONCLUSION This study confirmed the presence of hormetic models and the enhancement of survival rate in immunosuppressed BALB/c mice as a consequence of low-dose irradiation. It is also revealed the positive synergetic radioadaptive response on survival rate of immunosuppressed animals.
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Affiliation(s)
- M Alavi
- Ionizing and Non-Ionizing Radiation Protection Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - S Taeb
- Ionizing and Non-Ionizing Radiation Protection Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M A Okhovat
- Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical sciences, Shiraz, Iran
| | - M Atefi
- Ionizing and Non-Ionizing Radiation Protection Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran ; Master Student of Biophysics, Payame Noor University (PNU), Iran
| | - F Negahdari
- Department Of Mathematics, Neyriz Branch, Islamic Azad University, Neyriz, Iran
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25
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The potential use of biogas producing microorganisms in radiation protection. JOURNAL OF MEDICAL HYPOTHESES AND IDEAS 2015. [DOI: 10.1016/j.jmhi.2015.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Mortazavi SMJ, Niroomand-Rad A, Roshan-Shomal P, Razavi-Toosi SMT, Mossayeb-Zadeh M, Moghadam M. Does short-term exposure to elevated levels of natural gamma radiation in Ramsar cause oxidative stress? Int J Appl Basic Med Res 2014; 4:72-6. [PMID: 25143879 PMCID: PMC4137645 DOI: 10.4103/2229-516x.136778] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 01/17/2014] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Ramsar, a city in northern Iran, has areas with some of the highest recorded levels of natural radiation among inhabited areas measured on the earth. AIMS To determine whether short-term exposure to extremely high levels of natural radiation induce oxidative stress. MATERIALS AND METHODS In this study, 53 Wistar rats were randomly divided into five groups of 10-12 animals. Animals in the 1(st) group were kept for 7 days in an outdoor area with normal background radiation while the 2(nd) , 3(rd) , 4(th) and 5(th) groups were kept in four different outdoor areas with naturally elevated levels of gamma radiation in Ramsar. A calibrated RDS-110 survey meter, mounted on a tripod approximately 1 m above the ground, was used to measure exposure rate at each location. On days 7 and 9 blood sampling was performed to assess the serum levels of catalase (CAT) and malondialdehyde (MDA). On day 8, all animals were exposed to a lethal dose of 8 Gy gamma radiations emitted by a Theratron Phoenix (Theratronics, Canada) Cobalt-60 (55 cGy/min) at Radiotherapy Department of Razi Hospital in Rasht, Iran. RESULTS Findings obtained in this study indicate that high levels of natural radiation cannot induce oxidative stress. CAT and MDA levels in almost all groups were not significantly different (P = 0.69 and P = 0.05, respectively). After exposure to the lethal dose, CAT and MDA levels in all groups were not significantly different (P = 0.054 and P = 0.163, respectively). CONCLUSIONS These findings indicate that short-term exposure to extremely high levels of natural radiation (up to 196 times higher than the normal background) does not induce oxidative stress.
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Affiliation(s)
- SMJ Mortazavi
- Department of Medical Physics and Medical Engineering, Shiraz, Iran
- Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - A Niroomand-Rad
- Emeritus Professor, Department of Radiation Medicine, Georgetown University, Washington DC, USA
| | - P Roshan-Shomal
- Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - SMT Razavi-Toosi
- Department of Physiology, Tehran University of Medical Sciences, Tehran, Iran
| | - M Mossayeb-Zadeh
- Ionizing and Non-ionizing Radiation Protection Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M Moghadam
- Department of Nuclear Physics, Guilan University of Science, Rasht, Gilan, Iran
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Mortazavi SMJ, Motamedifar M, Namdari G, Taheri M, Mortazavi AR, Shokrpour N. Non-linear adaptive phenomena which decrease the risk of infection after pre-exposure to radiofrequency radiation. Dose Response 2013; 12:233-45. [PMID: 24910582 DOI: 10.2203/dose-response.12-055.mortazavi] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Substantial evidence indicates that adaptive response induced by low doses of ionizing radiation can result in resistance to the damage caused by a subsequently high-dose radiation or cause cross-resistance to other non-radiation stressors. Adaptive response contradicts the linear-non-threshold (LNT) dose-response model for ionizing radiation. We have previously reported that exposure of laboratory animals to radiofrequency radiation can induce a survival adaptive response. Furthermore, we have indicated that pre-exposure of mice to radiofrequency radiation emitted by a GSM mobile phone increased their resistance to a subsequent Escherichia coli infection. In this study, the survival rates in animals receiving both adapting (radiofrequency) and challenge dose (bacteria) and the animals receiving only the challenge dose (bacteria) were 56% and 20%, respectively. In this light, our findings contribute to the assumption that radiofrequency-induced adaptive response can be used as an efficient method for decreasing the risk of infection in immunosuppressed irradiated individuals. The implication of this phenomenon in human's long term stay in the space is also discussed.
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Affiliation(s)
- S M J Mortazavi
- Professor of Medical Physics, Medical Physics Department, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran; ; The Center for Research in Ionizing and Non-Ionizing Radiation, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M Motamedifar
- Associate Professor of Microbiology, Department of Bacteriology, School of Medicine and Shiraz HIV/Aids Research Center (SHARC), Shiraz University of Medical Sciences, Shiraz, Iran
| | - G Namdari
- Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - M Taheri
- Lecturer of Microbiology, Laboratory Sciences Department, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
| | - A R Mortazavi
- Student Research Committee, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - N Shokrpour
- Professor, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
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Mortazavi S, Motamedifar M, Namdari G, Taheri M, Mortazavi A. Counterbalancing immunosuppression-induced infections during long-term stay of humans in space. JOURNAL OF MEDICAL HYPOTHESES AND IDEAS 2013. [DOI: 10.1016/j.jmhi.2012.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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30
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Wang B, Ninomiya Y, Tanaka K, Maruyama K, Varès G, Eguchi-Kasai K, Nenoi M. Adaptive response of low linear energy transfer X-rays for protection against high linear energy transfer accelerated heavy ion-induced teratogenesis. ACTA ACUST UNITED AC 2012; 95:379-85. [PMID: 23109298 DOI: 10.1002/bdrb.21027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2012] [Accepted: 09/18/2012] [Indexed: 11/06/2022]
Abstract
BACKGROUND Adaptive response (AR) of low linear energy transfer (LET) irradiations for protection against teratogenesis induced by high LET irradiations is not well documented. In this study, induction of AR by X-rays against teratogenesis induced by accelerated heavy ions was examined in fetal mice. METHODS Irradiations of pregnant C57BL/6J mice were performed by delivering a priming low dose from X-rays at 0.05 or 0.30 Gy on gestation day 11 followed one day later by a challenge high dose from either X-rays or accelerated heavy ions. Monoenergetic beams of carbon, neon, silicon, and iron with the LET values of about 15, 30, 55, and 200 keV/μm, respectively, were examined. Significant suppression of teratogenic effects (fetal death, malformation of live fetuses, or low body weight) was used as the endpoint for judgment of a successful AR induction. RESULTS Existence of AR induced by low-LET X-rays against teratogenic effect induced by high-LET accelerated heavy ions was demonstrated. The priming low dose of X-rays significantly reduced the occurrence of prenatal fetal death, malformation, and/or low body weight induced by the challenge high dose from either X-rays or accelerated heavy ions of carbon, neon or silicon but not iron particles. CONCLUSIONS Successful AR induction appears to be a radiation quality event, depending on the LET value and/or the particle species of the challenge irradiations. These findings would provide a new insight into the study on radiation-induced AR in utero.
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Affiliation(s)
- Bing Wang
- Radiation Risk Reduction Research Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan.
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Mortazavi S, Mosleh-Shirazi M, Tavassoli A, Taheri M, Mehdizadeh A, Namazi S, Jamali A, Ghalandari R, Bonyadi S, Haghani M, Shafie M. Increased Radioresistance to Lethal Doses of Gamma Rays in Mice and Rats after Exposure to Microwave Radiation Emitted by a GSM Mobile Phone Simulator. Dose Response 2012; 11:281-92. [PMID: 23930107 DOI: 10.2203/dose-response.12-010.mortazavi] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The aim of this study was to investigate the effect of pre-irradiation with microwaves on the induction of radioadaptive response. In the 1(st) phase of the study, 110 male mice were divided into 8 groups. The animals in these groups were exposed/sham-exposed to microwave, low dose rate gamma or both for 5 days. On day six, the animals were exposed to a lethal dose (LD). In the 2(nd) phase, 30 male rats were divided into 2 groups of 15 animals. The 1(st) group received microwave exposure. The 2(nd) group (controls) received the same LD but there was no treatment before the LD. On day 5, all animals were whole-body irradiated with the LD. Statistically significant differences between the survival rate of the mice only exposed to lethal dose of gamma radiation before irradiation with a lethal dose of gamma radiation with those of the animals pre-exposed to either microwave (p=0.02), low dose rate gamma (p=0.001) or both of these physical adapting doses (p=0.003) were observed. Likewise, a statistically significant difference between survival rates of the rats in control and test groups was observed. Altogether, these experiments showed that exposure to microwave radiation may induce a significant survival adaptive response.
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Affiliation(s)
- Smj Mortazavi
- Professor of Medical Physics, Radiobiology & Radiation Protection Department, School of Allied Medical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran; ; The Center for Research in Radiological Sciences, School of Allied Medical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
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Abdollahi H, Teymouri M, Khademi S. Radiofrequency radiation may help astronauts in space missions. JOURNAL OF MEDICAL HYPOTHESES AND IDEAS 2012. [DOI: 10.1016/j.jmhi.2012.08.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Mortazavi SMJ, Rahmani MR, Rahnama A, Saeed-Pour A, Nouri E, Hosseini N, Aghaiee MM. The stimulatory effects of topical application of radioactive lantern mantle powder on wound healing. Dose Response 2009; 7:149-59. [PMID: 19543481 DOI: 10.2203/dose-response.08-022.mortazavi] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Some people in different parts of Iran use burned mantles as a wound healing medicine. To perform surface area measurement, twenty rats were divided randomly into two groups of 10 animals each. The 1st group received topical burned radioactive lantern mantle powder at 1st-3rd day after making excision wounds. The 2nd group received non-radioactive lantern mantle powder. For histological study, 36 male rats randomly divided into two groups of 18 animals each. Full thickness excision wound (314+/-31.4 mm(2)) was made on the dorsal neck in all animals after inducing general anesthesia. For the first 3 days, cases received topical application of the radioactive lantern mantle powder. Finally, to measure the tensile strength, an incision was made on the dorsal neck of the rats. Surface area measurement of the wounds showed a progressive surface reduction in both groups. Histological study showed a significant statistically difference between cases and controls with respect to fibrinoid necrosis and neutrophilic exudate at the days 3 and 14. Considering the existence of granulation tissue, a significant difference was observed between case and control groups at days 3 and 7. Tensile strength study showed no significant difference between the cases and controls until 30 days after excision.
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Affiliation(s)
- S M J Mortazavi
- The Center for Radiological Research, Shiraz University of Medical Sciences, Shiraz, Iran.
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Willey JS, Grilly LG, Howard SH, Pecaut MJ, Obenaus A, Gridley DS, Nelson GA, Bateman TA. Bone architectural and structural properties after 56Fe26+ radiation-induced changes in body mass. Radiat Res 2008; 170:201-7. [PMID: 18666808 DOI: 10.1667/rr0832.1] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2007] [Accepted: 04/21/2008] [Indexed: 11/03/2022]
Abstract
High-energy, high-charge (HZE) radiation, including iron ions ((56)Fe(26+)), is a component of the space environment. We recently observed a profound loss of trabecular bone in mice after whole-body HZE irradiation. The goal of this study was to examine morphology in bones that were excluded from a (56)Fe(26+) beam used to irradiate the body. Using 10-week-old male Sprague-Dawley rats and excluding the hind limbs and pelvis, we irradiated animals with 0, 1, 2 and 4 Gy (56)Fe(26+) ions and killed them humanely after 9 months. Animals grew throughout the experiment. Trabecular bone volume, connectivity and thickness within the proximal tibiae were significantly lower than control in a dose-dependent manner. Irradiated animals generally had less body mass than controls, which largely accounted for the variability in bone parameters as determined by ANCOVA. Likewise, lower cortical parameters were associated with reduced mass. However, lesser trabecular thickness in the 4-Gy group could not be attributed to body mass alone. Indicators of bone metabolism were generally unchanged, suggesting stabilized turnover. Exposure to (56)Fe(26+) ions can alter trabecular microarchitecture in shielded bones. Reduced body mass seems to be correlated with these deficits of trabecular and cortical bone.
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Affiliation(s)
- J S Willey
- Department of Bioengineering, Clemson University, Clemson, South Carolina, USA
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Dimova EG, Bryant PE, Chankova SG. Adaptive response: some underlying mechanisms and open questions. Genet Mol Biol 2008. [DOI: 10.1590/s1415-47572008000300002] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Aponte VM, Finch DS, Klaus DM. Considerations for non-invasive in-flight monitoring of astronaut immune status with potential use of MEMS and NEMS devices. Life Sci 2006; 79:1317-33. [PMID: 16757003 DOI: 10.1016/j.lfs.2006.04.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Revised: 03/25/2006] [Accepted: 04/04/2006] [Indexed: 11/19/2022]
Abstract
The dynamics of how astronauts' immune systems respond to space flight have been studied extensively, but the complex process has not to date been thoroughly characterized, nor have the underlying principles of what causes the immune system to change in microgravity been fully determined. Statistically significant results regarding overall immunological effects in space have not yet been established due to the relatively limited amount of experimental data available, and are further complicated by the findings not showing systematically reproducible trends. Collecting in vivo data during flight without affecting the system being measured would increase understanding of the immune response process. The aims of this paper are to briefly review the current knowledge regarding how the immune system is altered in space flight; to present a group of candidate biomarkers that could be useful for in-flight monitoring and give an overview of the current methods used to measure these markers; and finally, to further establish the need and usefulness of incorporating real-time analytical techniques for in-flight assessment of astronaut health, emphasizing the potential application of MEMS/NEMS devices.
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Affiliation(s)
- V M Aponte
- Aerospace Engineering Sciences, 429 UCB, University of Colorado, Boulder, 80309, USA.
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Matsumoto H, Takahashi A, Ohnishi T. Radiation-induced adaptive responses and bystander effects. ACTA ACUST UNITED AC 2005; 18:247-54. [PMID: 15858392 DOI: 10.2187/bss.18.247] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
A classical paradigm [correction of paradym] of radiation biology asserts that all radiation effects on cells, tissues and organisms are due to the direct action of radiation. However, there has been a recent growth of interest in the indirect actions of radiation including the radiation-induced adaptive response, the bystander effect, low-dose hypersensitivity, and genomic instability, which are specific modes of stress exhibited in response to low-dose/low-dose rate radiation. This review focuses on the radiation-induced bystander effect and the adaptive response, provides a description of the two phenomena, and discusses the contribution of the former to the latter.
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Affiliation(s)
- Hideki Matsumoto
- Department of Experimental Radiology and Health Physics, Faculty of Medical Science, University of Fukui, Matsuoka, Fukui, Japan.
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Kadhim MA, Moore SR, Goodwin EH. Interrelationships amongst radiation-induced genomic instability, bystander effects, and the adaptive response. Mutat Res 2004; 568:21-32. [PMID: 15530536 DOI: 10.1016/j.mrfmmm.2004.06.043] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2004] [Revised: 06/03/2004] [Accepted: 06/04/2004] [Indexed: 05/01/2023]
Abstract
Over the past two decades, our understanding of radiation biology has undergone a fundamental shift in paradigms away from deterministic "hit-effect" relationships and towards complex ongoing "cellular responses". These responses include now familiar, but still poorly understood, phenomena associated with radiation exposure such as bystander effects, genomic instability, and adaptive responses. All three have been observed at very low doses, and at time points far removed from the initial radiation exposure, and are extremely relevant for linear extrapolation to low doses; the adaptive response is particularly relevant when exposure is spread over a period of time. These are precisely the circumstances that are most relevant to understanding cancer risk associated with environmental and occupational radiation exposures. This review will provide a synthesis of the known, and proposed, interrelationships amongst low-dose cellular responses to radiation. It also will examine the potential importance of non-targeted cellular responses to ionizing radiation in setting acceptable exposure limits especially to low-LET radiations.
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Affiliation(s)
- Munira A Kadhim
- MRC Radiation and Genome Stability Unit, Harwell, Didcot, Oxfordshire OX110RD, UK.
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Durante M, Snigiryova G, Akaeva E, Bogomazova A, Druzhinin S, Fedorenko B, Greco O, Novitskaya N, Rubanovich A, Shevchenko V, Von Recklinghausen U, Obe G. Chromosome aberration dosimetry in cosmonauts after single or multiple space flights. Cytogenet Genome Res 2004; 103:40-6. [PMID: 15004462 DOI: 10.1159/000076288] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2003] [Accepted: 08/05/2003] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND AND AIMS Cosmic radiation is one of the main hazards for manned space exploration. Uncertainty in radiation risk estimates for crews of long-term missions are very high, and direct biological measurements are necessary. We measured chromosomal aberrations in peripheral blood lymphocytes from 33 cosmonauts involved in space missions during the past 11 years. METHODS Blood lymphocytes from the cosmonauts were stimulated to grow in vitro and were harvested at their first mitosis. Slides were either stained with Giemsa stain for dicentrics analysis, or painted with whole-chromosome DNA probes for translocation analysis (FISH). RESULTS A statistically significant increase in the yield of chromosomal aberrations was measured following long-term space missions in lymphocytes from cosmonauts at their first flight. No significant changes in aberration frequencies were observed for short-term taxi flights. The increase in long-term missions was consistent with the values calculated from physical dosimetry data. However, for cosmonauts involved in two or more space flights, the yield of interchromosomal exchanges was not related to the total duration of space sojourn or integral absorbed dose. Indeed, the yield of aberrations at the end of the last mission was generally in the range of background frequencies measured before the first mission. CONCLUSIONS Chromosome aberration dosimetry can detect radiation damage during space flight, and biological measurements support the current risk estimates for space radiation exposure. However, for cosmonauts involved in multiple space missions the frequency of chromosomal aberrations is lower than expected, suggesting that the effects of repeated space flights on this particular endpoint are not simply additive. Changes in the immune system in microgravity and/or adaptive response to space radiation may explain the apparent increase in radioresistance after multiple space flights.
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Affiliation(s)
- M Durante
- Department of Physics, University Federico II, Napoli, Italy
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