1
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Ramos RL, Carante MP, Bernardini E, Ferrari A, Sala P, Vercesi V, Ballarini F. A method to predict space radiation biological effectiveness for non-cancer effects following intense Solar Particle Events. LIFE SCIENCES IN SPACE RESEARCH 2024; 41:210-217. [PMID: 38670649 DOI: 10.1016/j.lssr.2024.03.006] [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: 12/15/2023] [Revised: 03/14/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024]
Abstract
In addition to the continuous exposure to cosmic rays, astronauts in space are occasionally exposed to Solar Particle Events (SPE), which involve less energetic particles but can deliver much higher doses. The latter can exceed several Gy in a few hours for the most intense SPEs, for which non-stochastic effects are thus a major concern. To identify adequate shielding conditions that would allow respecting the dose limits established by the various space agencies, the absorbed dose in the considered organ/tissue must be multiplied by the corresponding Relative Biological Effectiveness (RBE), which is a complex quantity depending on several factors including particle type and energy, considered biological effect, level of effect (and thus absorbed dose), etc. While in several studies only the particle-type dependence of RBE is taken into account, in this work we developed and applied a new approach where, thanks to an interface between the FLUKA Monte Carlo transport code and the BIANCA biophysical model, the RBE dependence on particle energy and absorbed dose was also considered. Furthermore, we included in the considered SPE spectra primary particles heavier than protons, which in many studies are neglected. This approach was then applied to the October 2003 SPE (the most intense SPE of solar cycle 23, also known as "Halloween event") and the January 2005 event, which was characterized by a lower fluence but a harder spectrum, i.e., with higher-energy particles. The calculation outcomes were then discussed and compared with the current dose limits established for skin and blood forming organs in case of 30-days missions. This work showed that the BIANCA model, if interfaced to a radiation transport code, can be used to calculate the RBE values associated to Solar Particle Events. More generally, this work emphasizes the importance of taking into account the RBE dependence on particle energy and dose when calculating equivalent doses.
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Affiliation(s)
- R L Ramos
- INFN, Sezione di Pavia, via Bassi 6, I-27100 Pavia, Italy
| | - M P Carante
- INFN, Sezione di Pavia, via Bassi 6, I-27100 Pavia, Italy; University of Pavia, Physics Department, via Bassi 6, I-27100 Pavia, Italy.
| | - E Bernardini
- Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milano, Italy
| | - A Ferrari
- Institute for Astroparticle Physics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | | | - V Vercesi
- INFN, Sezione di Pavia, via Bassi 6, I-27100 Pavia, Italy
| | - F Ballarini
- INFN, Sezione di Pavia, via Bassi 6, I-27100 Pavia, Italy; University of Pavia, Physics Department, via Bassi 6, I-27100 Pavia, Italy
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2
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Pfuhl T, Weber U, Horst F, Durante M, Schuy C. Ground-based passive generation of Solar Particle Event spectra: Planning and manufacturing of a 3D-printed modulator. Z Med Phys 2024; 34:153-165. [PMID: 37940400 DOI: 10.1016/j.zemedi.2023.10.002] [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: 05/20/2023] [Revised: 10/11/2023] [Accepted: 10/12/2023] [Indexed: 11/10/2023]
Abstract
The generation of space radiation on Earth is essential to study and predict the effects of radiation on space travelers, electronics, or materials during future long-term space missions. Next to the heavy ions of the galactic cosmic rays, solar particle events play a major role concerning the radiation risk in space, which consist of intermediate-energy protons with broad spectra and energies up to a few hundred MeV. This work describes an approach for the ground-based generation of solar particle events. As a proof of principle, a passive beam modulator with a specific funnel-shaped periodic structure was designed and is used to convert a monoenergetic proton beam into a spectral proton energy distribution, mimicking a solar particle event from August 1972, which is known as one of the strongest recorded SPE events. The required proton beam of 220 MeV can be generated at many existing particle accelerators at research or particle therapy facilities. The planning, manufacturing and testing of the modulator is described step by step. Its correct manufacturing and the characteristics of the solar particle event simulator are tested experimentally and by means of Monte Carlo simulations. Future modulators will follow the same concept with minor adjustments such as a larger lateral extension. As of now, the presented beam modulator is available to the research community to conduct experiments at GSI for exposure under solar particle event conditions. In addition, researchers can use and apply the described concept to design and print their individualized modulator to reproduce any desired solar particle event spectrum or request the presented modulator geometry from the authors.
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Affiliation(s)
- Tabea Pfuhl
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany
| | - Uli Weber
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany.
| | - Felix Horst
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany; OncoRay - Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany(1)
| | - Marco Durante
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany; Technische Universität Darmstadt, Institut für Physik Kondensierter Materie, Darmstadt, Germany
| | - Christoph Schuy
- GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt, Germany
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3
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Dose Limits and Countermeasures for Mitigating Radiation Risk in Moon and Mars Exploration. PHYSICS 2022. [DOI: 10.3390/physics4010013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
After decades of research on low-Earth orbit, national space agencies and private entrepreneurs are investing in exploration of the Solar system. The main health risk for human space exploration is late toxicity caused by exposure to cosmic rays. On Earth, the exposure of radiation workers is regulated by dose limits and mitigated by shielding and reducing exposure times. For space travel, different international space agencies adopt different limits, recently modified as reviewed in this paper. Shielding and reduced transit time are currently the only practical solutions to maintain acceptable risks in deep space missions.
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4
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Puig J, Knödlseder N, Quera J, Algara M, Güell M. DNA Damage Protection for Enhanced Bacterial Survival Under Simulated Low Earth Orbit Environmental Conditions in Escherichia coli. Front Microbiol 2022; 12:789668. [PMID: 34970246 PMCID: PMC8713957 DOI: 10.3389/fmicb.2021.789668] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 11/23/2021] [Indexed: 11/13/2022] Open
Abstract
Some organisms have shown the ability to naturally survive in extreme environments, even outer space. Some of these have natural mechanisms to resist severe DNA damage from conditions such as ionizing and non-ionizing radiation, extreme temperatures, and low pressures or vacuum. A good example can be found in Deinococcus radiodurans, which was exposed to severe conditions such as those listed in the Exposure Facility of the International Space Station (ISS) for up to three years. Another example are tardigrades (Ramazzottius varieornatus) which are some of the most resilient animals known. In this study, the survival under simulated Low earth Orbit (LEO) environmental conditions was tested in Escherichia coli. The radiation resistance of this bacteria was enhanced using the Dsup gene from R. varieornatus, and two more genes from D. radiodurans involved in DNA damage repair, RecA and uvrD. The enhanced survival to wide ranges of temperatures and low pressures was then tested in the new strains. This research constitutes a first step in the creation of new bacterial strains engineered to survive severe conditions and adapting existing species for their survival in remote environments, including extra-terrestrial habitats. These strains could be key for the development of environments hospitable to life and could be of use for ecological restoration and space exploration. In addition, studying the efficacy and the functioning of the DNA repair mechanisms used in this study could be beneficial for medical and life sciences engineering.
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Affiliation(s)
- Jaume Puig
- Translational Synthetic Biology Laboratory, Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain.,Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain
| | - Nastassia Knödlseder
- Translational Synthetic Biology Laboratory, Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain.,Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain
| | - Jaume Quera
- Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain.,Radiation Oncology Department, Hospital del Mar, Parc de Salut Mar, Barcelona, Spain.,IMIM Hospital del Mar Medical Research Institute, Barcelona, Spain
| | - Manuel Algara
- Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain.,Radiation Oncology Department, Hospital del Mar, Parc de Salut Mar, Barcelona, Spain.,IMIM Hospital del Mar Medical Research Institute, Barcelona, Spain
| | - Marc Güell
- Translational Synthetic Biology Laboratory, Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain.,Experimental and Health Sciences Department, Universitat Pompeu Fabra, Barcelona, Spain
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5
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An easy-to-use function to assess deep space radiation in human brains. Sci Rep 2021; 11:11687. [PMID: 34083566 PMCID: PMC8175378 DOI: 10.1038/s41598-021-90695-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 05/06/2021] [Indexed: 11/25/2022] Open
Abstract
Health risks from radiation exposure in space are an important factor for astronauts’ safety as they venture on long-duration missions to the Moon or Mars. It is important to assess the radiation level inside the human brain to evaluate the possible hazardous effects on the central nervous system especially during solar energetic particle (SEP) events. We use a realistic model of the head/brain structure and calculate the radiation deposit therein by realistic SEP events, also under various shielding scenarios. We then determine the relation between the radiation dose deposited in different parts of the brain and the properties of the SEP events and obtain some simple and ready-to-use functions which can be used to quickly and reliably forecast the event dose in the brain. Such a novel tool can be used from fast nowcasting of the consequences of SEP events to optimization of shielding systems and other mitigation strategies of astronauts in space.
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6
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Restier-Verlet J, El-Nachef L, Ferlazzo ML, Al-Choboq J, Granzotto A, Bouchet A, Foray N. Radiation on Earth or in Space: What Does It Change? Int J Mol Sci 2021; 22:3739. [PMID: 33916740 PMCID: PMC8038356 DOI: 10.3390/ijms22073739] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 03/28/2021] [Accepted: 03/29/2021] [Indexed: 12/15/2022] Open
Abstract
After having been an instrument of the Cold War, space exploration has become a major technological, scientific and societal challenge for a number of countries. With new projects to return to the Moon and go to Mars, radiobiologists have been called upon to better assess the risks linked to exposure to radiation emitted from space (IRS), one of the major hazards for astronauts. To this aim, a major task is to identify the specificities of the different sources of IRS that concern astronauts. By considering the probabilities of the impact of IRS against spacecraft shielding, three conclusions can be drawn: (1) The impacts of heavy ions are rare and their contribution to radiation dose may be low during low Earth orbit; (2) secondary particles, including neutrons emitted at low energy from the spacecraft shielding, may be common in deep space and may preferentially target surface tissues such as the eyes and skin; (3) a "bath of radiation" composed of residual rays and fast neutrons inside the spacecraft may present a concern for deep tissues such as bones and the cardiovascular system. Hence, skin melanoma, cataracts, loss of bone mass, and aging of the cardiovascular system are possible, dependent on the dose, dose-rate, and individual factors. This suggests that both radiosusceptibility and radiodegeneration may be concerns related to space exploration. In addition, in the particular case of extreme solar events, radiosensitivity reactions-such as those observed in acute radiation syndrome-may occur and affect blood composition, gastrointestinal and neurologic systems. This review summarizes the specificities of space radiobiology and opens the debate as regards refinements of current radiation protection concepts that will be useful for the better estimation of risks.
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Affiliation(s)
| | | | | | | | | | | | - Nicolas Foray
- Inserm, U1296 Unit, «Radiation: Defense, Health and Environment», Centre Léon-Bérard, 28, Rue Laennec, 69008 Lyon, France; (J.R.-V.); (L.E.-N.); (M.L.F.); (J.A.-C.); (A.G.); (A.B.)
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7
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Chancellor J, Nowadly C, Williams J, Aunon-Chancellor S, Chesal M, Looper J, Newhauser W. Everything you wanted to know about space radiation but were afraid to ask. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:113-128. [PMID: 33902392 DOI: 10.1080/26896583.2021.1897273] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The space radiation environment is a complex combination of fast-moving ions derived from all atomic species found in the periodic table. The energy spectrum of each ion species varies widely but is prominently in the range of 400-600 MeV/n. The large dynamic range in ion energy is difficult to simulate in ground-based radiobiology experiments. Most ground-based irradiations with mono-energetic beams of a single one ion species are delivered at comparatively high dose rates. In some cases, sequences of such beams are delivered with various ion species and energies to crudely approximate the complex space radiation environment. This approximation may cause profound experimental bias in processes such as biologic repair of radiation damage, which are known to have strong temporal dependencies. It is possible that this experimental bias leads to an over-prediction of risks of radiation effects that have not been observed in the astronaut cohort. None of the primary health risks presumably attributed to space radiation exposure, such as radiation carcinogenesis, cardiovascular disease, cognitive deficits, etc., have been observed in astronaut or cosmonaut crews. This fundamentally and profoundly limits our understanding of the effects of GCR on humans and limits the development of effective radiation countermeasures.
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Affiliation(s)
- Jeffery Chancellor
- Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana, USA
- Department of Preventive Medicine & Population Health, University of Texas Medical Branch, Galveston, Texas, USA
- Outer Space Insititute, Universit of British Columbia, CA
| | - Craig Nowadly
- Department of Emergency Medicine, Brooke Army Medical Center, Fort Sam Houston, Texas, USA
| | - Jacqueline Williams
- Departments of Environmental Medicine & Radiation Oncology, University of Rochester Medical Center, Rochester, New York, USA
| | - Serena Aunon-Chancellor
- Department of Preventive Medicine & Population Health, University of Texas Medical Branch, Galveston, Texas, USA
- Department of Internal Medicine, LSU Health Science Center, Baton Rouge, Louisiana, USA
- Astronaut Office, NASA Johnson Space Center, Houston, Texas, USA
| | - Megan Chesal
- Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana, USA
| | - Jayme Looper
- Department of Veterinary Clinical Sciences, LSU School of Veterinary Medicine, Baton Rouge, Louisiana, USA
| | - Wayne Newhauser
- Department of Physics & Astronomy, Louisiana State University, Baton Rouge, Louisiana, USA
- Department of Physics, Mary Bird Perkins Cancer Center, Baton Rouge, Louisiana, USA
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8
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Willey JS, Britten RA, Blaber E, Tahimic CG, Chancellor J, Mortreux M, Sanford LD, Kubik AJ, Delp MD, Mao XW. The individual and combined effects of spaceflight radiation and microgravity on biologic systems and functional outcomes. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART C, TOXICOLOGY AND CARCINOGENESIS 2021; 39:129-179. [PMID: 33902391 PMCID: PMC8274610 DOI: 10.1080/26896583.2021.1885283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Both microgravity and radiation exposure in the spaceflight environment have been identified as hazards to astronaut health and performance. Substantial study has been focused on understanding the biology and risks associated with prolonged exposure to microgravity, and the hazards presented by radiation from galactic cosmic rays (GCR) and solar particle events (SPEs) outside of low earth orbit (LEO). To date, the majority of the ground-based analogues (e.g., rodent or cell culture studies) that investigate the biology of and risks associated with spaceflight hazards will focus on an individual hazard in isolation. However, astronauts will face these challenges simultaneously Combined hazard studies are necessary for understanding the risks astronauts face as they travel outside of LEO, and are also critical for countermeasure development. The focus of this review is to describe biologic and functional outcomes from ground-based analogue models for microgravity and radiation, specifically highlighting the combined effects of radiation and reduced weight-bearing from rodent ground-based tail suspension via hind limb unloading (HLU) and partial weight-bearing (PWB) models, although in vitro and spaceflight results are discussed as appropriate. The review focuses on the skeletal, ocular, central nervous system (CNS), cardiovascular, and stem cells responses.
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Affiliation(s)
| | | | - Elizabeth Blaber
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | | | | | - Marie Mortreux
- Department of Neurology, Harvard Medical School, Beth Israel Deaconess Medical Center
| | - Larry D. Sanford
- Department of Radiation Oncology, Eastern Virginia Medical School
| | - Angela J. Kubik
- Department of Biomedical Engineering, Rensselaer Polytechnic Institute
| | - Michael D. Delp
- Department of Nutrition, Food and Exercise Sciences, Florida State University
| | - Xiao Wen Mao
- Division of Biomedical Engineering Sciences (BMES), Department of Basic Sciences, Loma Linda University
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9
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DeWitt J, Benton E. Shielding effectiveness: A weighted figure of merit for space radiation shielding. Appl Radiat Isot 2020; 161:109141. [DOI: 10.1016/j.apradiso.2020.109141] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 03/11/2020] [Accepted: 03/19/2020] [Indexed: 10/24/2022]
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10
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Chancellor JC, Blue RS, Cengel KA, Auñón-Chancellor SM, Rubins KH, Katzgraber HG, Kennedy AR. Limitations in predicting the space radiation health risk for exploration astronauts. NPJ Microgravity 2018; 4:8. [PMID: 29644336 PMCID: PMC5882936 DOI: 10.1038/s41526-018-0043-2] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Revised: 02/20/2018] [Accepted: 03/12/2018] [Indexed: 12/23/2022] Open
Abstract
Despite years of research, understanding of the space radiation environment and the risk it poses to long-duration astronauts remains limited. There is a disparity between research results and observed empirical effects seen in human astronaut crews, likely due to the numerous factors that limit terrestrial simulation of the complex space environment and extrapolation of human clinical consequences from varied animal models. Given the intended future of human spaceflight, with efforts now to rapidly expand capabilities for human missions to the moon and Mars, there is a pressing need to improve upon the understanding of the space radiation risk, predict likely clinical outcomes of interplanetary radiation exposure, and develop appropriate and effective mitigation strategies for future missions. To achieve this goal, the space radiation and aerospace community must recognize the historical limitations of radiation research and how such limitations could be addressed in future research endeavors. We have sought to highlight the numerous factors that limit understanding of the risk of space radiation for human crews and to identify ways in which these limitations could be addressed for improved understanding and appropriate risk posture regarding future human spaceflight.
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Affiliation(s)
- Jeffery C Chancellor
- 1Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843-4242 USA
| | - Rebecca S Blue
- 2Aerospace Medicine and Vestibular Research Laboratory, The Mayo Clinic Arizona, Scottsdale, AZ 85054 USA
| | - Keith A Cengel
- 3Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
| | - Serena M Auñón-Chancellor
- 4National Aeronautics and Space Administration (NASA), Johnson Space Center, Houston, 77058 USA.,5University of Texas Medical Branch, Galveston, TX 77555 USA
| | - Kathleen H Rubins
- 4National Aeronautics and Space Administration (NASA), Johnson Space Center, Houston, 77058 USA
| | - Helmut G Katzgraber
- 1Department of Physics and Astronomy, Texas A&M University, College Station, TX 77843-4242 USA.,1QB Information Technologies (1QBit), Vancouver, BC V6B 4W4 Canada.,7Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501 USA
| | - Ann R Kennedy
- 3Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104 USA
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11
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Bahadori A, Semones E, Ewert M, Broyan J, Walker S. Measuring space radiation shielding effectiveness. EPJ WEB OF CONFERENCES 2017. [DOI: 10.1051/epjconf/201715304001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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12
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Kim SB, Bozeman RG, Kaisani A, Kim W, Zhang L, Richardson JA, Wright WE, Shay JW. Radiation promotes colorectal cancer initiation and progression by inducing senescence-associated inflammatory responses. Oncogene 2015; 35:3365-75. [PMID: 26477319 PMCID: PMC4837107 DOI: 10.1038/onc.2015.395] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 08/27/2015] [Accepted: 09/08/2015] [Indexed: 12/29/2022]
Abstract
Proton radiotherapy is becoming more common since protons induce more precise DNA damage at the tumor site with reduced side effects to adjacent normal tissues. However, the long-term biological effects of proton irradiation in cancer initiation compared to conventional photon irradiation are poorly characterized. In this study, using a human familial adenomatous polyposis syndrome susceptible mouse model, we show that whole body irradiation with protons are more effective in inducing senescence-associated inflammatory responses (SIR) which are involved in colon cancer initiation and progression. After proton irradiation, a subset of SIR genes (Troy, Sox17, Opg, Faim2, Lpo, Tlr2 and Ptges) and a gene known to be involved in invasiveness (Plat), along with the senescence associated gene (P19Arf) are markedly increased. Following these changes loss of Casein kinase Iα (CKIα) and induction of chronic DNA damage and TP53 mutations are increased compared to x-ray irradiation. Proton irradiation also increases the number of colonic polyps, carcinomas and invasive adenocarcinomas. Pretreatment with the non-steroidal anti-inflammatory drug, CDDO-EA, reduces proton irradiation associated SIR and tumorigenesis. Thus, exposure to proton irradiation elicits significant changes in colorectal cancer initiation and progression that can be mitigated using CDDO-EA.
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Affiliation(s)
- S B Kim
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - R G Bozeman
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - A Kaisani
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - W Kim
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - L Zhang
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - J A Richardson
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Department of Plastic Surgery, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - W E Wright
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - J W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA.,Center of Excellence in Genomic Medicine Research, King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia
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13
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Aghara SK, Sriprisan SI, Singleterry RC, Sato T. Shielding evaluation for solar particle events using MCNPX, PHITS and OLTARIS codes. LIFE SCIENCES IN SPACE RESEARCH 2015; 4:79-91. [PMID: 26177623 DOI: 10.1016/j.lssr.2014.12.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 12/17/2014] [Accepted: 12/23/2014] [Indexed: 06/04/2023]
Abstract
Detailed analyses of Solar Particle Events (SPE) were performed to calculate primary and secondary particle spectra behind aluminum, at various thicknesses in water. The simulations were based on Monte Carlo (MC) radiation transport codes, MCNPX 2.7.0 and PHITS 2.64, and the space radiation analysis website called OLTARIS (On-Line Tool for the Assessment of Radiation in Space) version 3.4 (uses deterministic code, HZETRN, for transport). The study is set to investigate the impact of SPEs spectra transporting through 10 or 20 g/cm(2) Al shield followed by 30 g/cm(2) of water slab. Four historical SPE events were selected and used as input source spectra particle differential spectra for protons, neutrons, and photons are presented. The total particle fluence as a function of depth is presented. In addition to particle flux, the dose and dose equivalent values are calculated and compared between the codes and with the other published results. Overall, the particle fluence spectra from all three codes show good agreement with the MC codes showing closer agreement compared to the OLTARIS results. The neutron particle fluence from OLTARIS is lower than the results from MC codes at lower energies (E<100 MeV). Based on mean square difference analysis the results from MCNPX and PHITS agree better for fluence, dose and dose equivalent when compared to OLTARIS results.
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Affiliation(s)
- S K Aghara
- University of Massachusetts Lowell, Chemical Engineering, 1 University Avenue, Lowell, MA 01854, United States.
| | - S I Sriprisan
- University of Massachusetts Lowell, Chemical Engineering, 1 University Avenue, Lowell, MA 01854, United States
| | - R C Singleterry
- NASA Langley Research Center, 2 West Reid Street, MS 188E, Hampton, VA 23681, United States
| | - T Sato
- Japan Atomic Energy Agency, 2-4, Shirakata-Shirane, Tokai, Ibaraki 319-1195, Japan
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14
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Kim SB, Zhang L, Barron S, Shay JW. Inhibition of microRNA-31-5p protects human colonic epithelial cells against ionizing radiation. LIFE SCIENCES IN SPACE RESEARCH 2014; 1:67-73. [PMID: 26432591 DOI: 10.1016/j.lssr.2014.02.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 01/31/2014] [Accepted: 02/03/2014] [Indexed: 06/05/2023]
Abstract
MicroRNAs (miRNAs), endogenous non-coding small RNAs, are sensitive to environmental changes, and their differential expression is important for adaptation to the environment. However, application of miRNAs as a clinical prognostic or diagnostic tool remains unproven. In this study we demonstrate a chronic/persistent change of miRNAs from the plasma of a colorectal cancer susceptible mouse model (CPC;Apc) about 250 days after exposure to a simulated solar particle event (SPE). Differentially expressed miRNAs were identified compared to unirradiated control mice, including miR-31-5p, which we investigated further. To address the cellular function of miR-31-5p, we transfected a miR-31-5p mimic (sense) or inhibitor (antisense) into immortalized human colonic epithelial cells followed by gamma-irradiation. A miR-31-5p mimic sensitized but a miR-31-5p inhibitor protected colonic epithelial cells against radiation induced killing. We found that the miR-31-5p mimic inhibited the induction of hMLH1 expression after irradiation, whereas the miR-31-5p inhibitor increased the basal level of hMLH1 expression. The miR-31-5p inhibitor failed to modulate radiosensitivity in an hMLH1-deficient HCT116 colon cancer cell line but protected HCT116 3-6 and DLD-1 (both hMLH1-positive) colon cancer cell lines. Our findings demonstrate that miR-31-5p has an important role in radiation responses through regulation of hMLH1 expression. Targeting this pathway could be a promising therapeutic strategy for future personalized anti-cancer radiotherapy.
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Affiliation(s)
- Sang Bum Kim
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9039, United States
| | - Lu Zhang
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9039, United States
| | - Summer Barron
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9039, United States
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-9039, United States.
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Abstract
During their occupational activities in space, astronauts are exposed to ionising radiation from natural radiation sources present in this environment. They are, however, not usually classified as being occupationally exposed in the sense of the general ICRP system for radiation protection of workers applied on Earth. The exposure assessment and risk-related approach described in this report is clearly restricted to the special situation in space, and should not be applied to any other exposure situation on Earth. The report describes the terms and methods used to assess the radiation exposure of astronauts, and provides data for the assessment of organ doses. Chapter 1 describes the specific situation of astronauts in space, and the differences in the radiation fields compared with those on Earth. In Chapter 2, the radiation fields in space are described in detail, including galactic cosmic radiation, radiation from the Sun and its special solar particle events, and the radiation belts surrounding the Earth. Chapter 3 deals with the quantities used in radiological protection, describing the Publication 103 (ICRP, 2007) system of dose quantities, and subsequently presenting the special approach for applications in space; due to the strong contribution of heavy ions in the radiation field, radiation weighting is based on the radiation quality factor, Q, instead of the radiation weighting factor, wR. In Chapter 4, the methods of fluence and dose measurement in space are described, including instrumentation for fluence measurements, radiation spectrometry, and area and individual monitoring. The use of biomarkers for the assessment of mission doses is also described. The methods of determining quantities describing the radiation fields within a spacecraft are given in Chapter 5. Radiation transport calculations are the most important tool. Some physical data used in radiation transport codes are presented, and the various codes used for calculations in high-energy radiation fields in space are described. Results of calculations and measurements of radiation fields in spacecraft are given. Some data for shielding possibilities are also presented. Chapter 6 addresses methods of determining mean absorbed doses and dose equivalents in organs and tissues of the human body. Calculated conversion coefficients of fluence to mean absorbed dose in an organ or tissue are given for heavy ions up to Z=28 for energies from 10 MeV/u to 100 GeV/u. For the same set of ions and ion energies, mean quality factors in organs and tissues are presented using, on the one hand, the Q(L) function defined in Publication 60 (ICRP, 1991), and, on the other hand, a Q function proposed by the National Aeronautics and Space Administration. Doses in the body obtained by measurements are compared with results from calculations, and biodosimetric measurements for the assessment of mission doses are also presented. In Chapter 7, operational measures are considered for assessment of the exposure of astronauts during space missions. This includes preflight mission design, area and individual monitoring during flights in space, and dose recording. The importance of the magnitude of uncertainties in dose assessment is considered. Annex A shows conversion coefficients and mean quality factors for protons, charged pions, neutrons, alpha particles, and heavy ions(2 < Z ≤2 8), and particle energies up to 100 GeV/u.
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17
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Sanzari JK, Muehlmatt A, Savage A, Lin L, Kennedy AR. Increased intracranial pressure in mini-pigs exposed to simulated solar particle event radiation. ACTA ASTRONAUTICA 2014; 94:807-812. [PMID: 25242832 PMCID: PMC4166565 DOI: 10.1016/j.actaastro.2013.10.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Changes in intracranial pressure (ICP) during space flight have stimulated an area of research in space medicine. It is widely speculated that elevations in ICP contribute to structural and functional ocular changes, including deterioration in vision, which is also observed during space flight. The aim of this study was to investigate changes in OP occurring as a result of ionizing radiation exposure (at doses and dose-rates relevant to solar particle event radiation). We used a large animal model, the Yucatan mini-pig, and were able to obtain measurements over a 90 day period. This is the first investigation to show long term recordings of ICP in a large animal model without an invasive craniotomy procedure. Further, this is the first investigation reporting increased ICP after radiation exposure.
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Affiliation(s)
| | | | | | | | - AR Kennedy
- Corresponding author: Ann R. Kennedy, D. Sc., 3620 Hamilton Walk, 183 John Morgan Building, Philadelphia, PA, 19104, USA, , (w) +1 215-898-0079, (f) +1 215-898-1141
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Kawaguchi Y, Yang Y, Kawashiri N, Shiraishi K, Takasu M, Narumi I, Satoh K, Hashimoto H, Nakagawa K, Tanigawa Y, Momoki YH, Tanabe M, Sugino T, Takahashi Y, Shimizu Y, Yoshida S, Kobayashi K, Yokobori SI, Yamagishi A. The possible interplanetary transfer of microbes: assessing the viability of Deinococcus spp. under the ISS Environmental conditions for performing exposure experiments of microbes in the Tanpopo mission. ORIGINS LIFE EVOL B 2013; 43:411-28. [PMID: 24132659 DOI: 10.1007/s11084-013-9346-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Accepted: 09/16/2013] [Indexed: 01/29/2023]
Abstract
To investigate the possible interplanetary transfer of life, numerous exposure experiments have been carried out on various microbes in space since the 1960s. In the Tanpopo mission, we have proposed to carry out experiments on capture and space exposure of microbes at the Exposure Facility of the Japanese Experimental Module of the International Space Station (ISS). Microbial candidates for the exposure experiments in space include Deinococcus spp.: Deinococcus radiodurans, D. aerius and D. aetherius. In this paper, we have examined the survivability of Deinococcus spp. under the environmental conditions in ISS in orbit (i.e., long exposure to heavy-ion beams, temperature cycles, vacuum and UV irradiation). A One-year dose of heavy-ion beam irradiation did not affect the viability of Deinococcus spp. within the detection limit. Vacuum (10(-1) Pa) also had little effect on the cell viability. Experiments to test the effects of changes in temperature from 80 °C to -80 °C in 90 min (± 80 °C/90 min cycle) or from 60 °C to -60 °C in 90 min (± 60 °C/90 min cycle) on cell viability revealed that the survival rate decreased severely by the ± 80 °C/90 min temperature cycle. Exposure of various thicknesses of deinococcal cell aggregates to UV radiation (172 nm and 254 nm, respectively) revealed that a few hundred micrometer thick aggregate of deinococcal cells would be able to withstand the solar UV radiation on ISS for 1 year. We concluded that aggregated deinococcal cells will survive the yearlong exposure experiments. We propose that microbial cells can aggregate as an ark for the interplanetary transfer of microbes, and we named it 'massapanspermia'.
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Affiliation(s)
- Yuko Kawaguchi
- Laboratory for Extremophiles, Department of Applied Molecular Biology, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
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19
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Lu X, Nurmemet D, Bolduc DL, Elliott TB, Kiang JG. Radioprotective effects of oral 17-dimethylaminoethylamino-17-demethoxygeldanamycin in mice: bone marrow and small intestine. Cell Biosci 2013; 3:36. [PMID: 24499553 PMCID: PMC3852109 DOI: 10.1186/2045-3701-3-36] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 08/01/2013] [Indexed: 01/05/2023] Open
Abstract
Background Our previous research demonstrated that one subcutaneous injection of 17-Dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) 24 hours (h) before irradiation (8.75 Gy) increased mouse survival by 75%. However, the protective mechanism of 17-DMAG is currently unknown. The present study aimed to investigate whether oral administration of 17-DMAG was also radioprotective and the potential role it may play in radioprotection. Results A single dose of orally pre-administered (24, 48, or 72 h) 17-DMAG (10 mg/kg) increased irradiated mouse survival, reduced body weight loss, improved water consumption, and decreased facial dropsy, whereas orally post-administered 17-DMAG failed. Additional oral doses of pre-treatment did not improve 30-day survival. The protective effect of multiple pre-administrations (2−3 times) of 17-DMAG at 10 mg/kg was equal to the outcome of a single pre-treatment. In 17-DMAG-pretreated mice, attenuation of bone marrow aplasia in femurs 30 days after irradiation with recovered expressions of cluster of differentiation 34, 44 (CD34, CD44), and survivin in bone marrow cells were observed. 17-DMAG also elevated serum granulocyte-colony stimulating factor (G-CSF), decreased serum fms-related tyrosine kinase 3 ligand, and reduced white blood cell depletion. 17-DMAG ameliorated small intestinal histological damage, promoted recovery of villus heights and intestinal crypts including stem cells, where increased leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5) was found 30 days after irradiation. Conclusions 17-DMAG is a potential radioprotectant for bone marrow and small intestine that results in survival improvement.
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Affiliation(s)
- Xinyue Lu
- Radiation Combined Injury Program, Scientific Research Department, Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889-5603, USA.
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20
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Sanzari JK, Wan XS, Krigsfeld GS, King GL, Miller A, Mick R, Gridley DS, Wroe AJ, Rightnar S, Dolney D, Kennedy AR. Effects of solar particle event proton radiation on parameters related to ferret emesis. Radiat Res 2013; 180:166-76. [PMID: 23883319 PMCID: PMC3837533 DOI: 10.1667/rr3173.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The effectiveness of simulated solar particle event (SPE) proton radiation to induce retching and vomiting was evaluated in the ferret experimental animal model. The endpoints measured in the study included: (1) the fraction of animals that retched or vomited, (2) the number of retches or vomits observed, (3) the latency period before the first retch or vomit and (4) the duration between the first and last retching or vomiting events. The results demonstrated that γ ray and proton irradiation delivered at a high dose rate of 0.5 Gy/min induced dose-dependent changes in the endpoints related to retching and vomiting. The minimum radiation doses required to induce statistically significant changes in retching- and vomiting-related endpoints were 0.75 and 1.0 Gy, respectively, and the relative biological effectiveness (RBE) of proton radiation at the high dose rate did not significantly differ from 1. Similar but less consistent and smaller changes in the retching- and vomiting-related endpoints were observed for groups irradiated with γ rays and protons delivered at a low dose rate of 0.5 Gy/h. Since this low dose rate is similar to a radiation dose rate expected during a SPE, these results suggest that the risk of SPE radiation-induced vomiting is low and may reach statistical significance only when the radiation dose reaches 1 Gy or higher.
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Affiliation(s)
- J. K. Sanzari
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia Pennsylvania
| | - X. S. Wan
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia Pennsylvania
| | - G. S. Krigsfeld
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia Pennsylvania
| | - G. L. King
- Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - A. Miller
- Scientific Research Department, Armed Forces Radiobiology Research Institute, Uniformed Services University of the Health Sciences, Bethesda, Maryland
| | - R. Mick
- Department of Biostatistics & Epidemiology, University of Pennsylvania Perelman School of Medicine, Philadelphia Pennsylvania
| | - D. S. Gridley
- Department of Radiation Medicine, Radiation Research Laboratories, Loma Linda University and Medical Center, Loma Linda, California
| | - A. J. Wroe
- Department of Radiation Medicine, Radiation Research Laboratories, Loma Linda University and Medical Center, Loma Linda, California
| | - S. Rightnar
- Department of Radiation Medicine, Radiation Research Laboratories, Loma Linda University and Medical Center, Loma Linda, California
| | - D. Dolney
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia Pennsylvania
| | - A. R. Kennedy
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia Pennsylvania
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21
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Sanzari JK, Wan XS, Wroe AJ, Rightnar S, Cengel KA, Diffenderfer ES, Krigsfeld GS, Gridley DS, Kennedy AR. Acute hematological effects of solar particle event proton radiation in the porcine model. Radiat Res 2013; 180:7-16. [PMID: 23672458 DOI: 10.1667/rr3027.1] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Acute radiation sickness (ARS) is expected to occur in astronauts during large solar particle events (SPEs). One parameter associated with ARS is the hematopoietic syndrome, which can result from decreased numbers of circulating blood cells in those exposed to radiation. The peripheral blood cells are critical for an adequate immune response, and low blood cell counts can result in an increased susceptibility to infection. In this study, Yucatan minipigs were exposed to proton radiation within a range of skin dose levels expected for an SPE (estimated from previous SPEs). The proton-radiation exposure resulted in significant decreases in total white blood cell count (WBC) within 1 day of exposure, 60% below baseline control value or preirradiation values. At the lowest level of the blood cell counts, lymphocytes, neutrophils, monocytes and eosinophils were decreased up to 89.5%, 60.4%, 73.2% and 75.5%, respectively, from the preirradiation values. Monocytes and lymphocytes were decreased by an average of 70% (compared to preirradiation values) as early as 4 h after radiation exposure. Skin doses greater than 5 Gy resulted in decreased blood cell counts up to 90 days after exposure. The results reported here are similar to studies of ARS using the nonhuman primate model, supporting the use of the Yucatan minipig as an alternative. In addition, the high prevalence of hematologic abnormalities resulting from exposure to acute, whole-body SPE-like proton radiation warrants the development of appropriate countermeasures to prevent or treat ARS occurring in astronauts during space travel.
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Affiliation(s)
- J K Sanzari
- Department of Radiation Oncology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA
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22
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Kim MHY, Wilson JW, Cucinotta FA. Description of transport codes for space radiation shielding. HEALTH PHYSICS 2012; 103:621-639. [PMID: 23032892 DOI: 10.1097/hp.0b013e318266732f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Exposure to ionizing radiation in the space environment is one of the hazards faced by crews in space missions. As space radiations traverse spacecraft, habitat shielding, or tissues, their energies and compositions are altered by interactions with the shielding. Modifications to the radiation fields arise from atomic interactions of charged particles with orbital electrons and nuclear interactions leading to projectile and target fragmentation, including secondary particles such as neutrons, protons, mesons, and nuclear recoils. The transport of space radiation through shielding can be simulated using Monte Carlo techniques or deterministic solutions of the Boltzmann equation. To determine shielding requirements and to resolve radiation constraints for future human missions, the shielding evaluation of a spacecraft concept is required as an early step in the design process. To do this requires (1) accurate knowledge of space environmental models to define the boundary condition for transport calculations, (2) transport codes with detailed shielding and body geometry models to determine particle transmission into areas of internal shielding and at each critical body organ, and (3) the assessment of organ dosimetric quantities and biological risks by applying the corresponding response models for space radiation against the particle spectra that have been accurately determined from the transport code. This paper reviews current transport codes and analyzes their accuracy through comparison to laboratory and spaceflight data. This paper also introduces a probabilistic risk assessment approach for the evaluation of radiation shielding.
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Affiliation(s)
- Myung-Hee Y Kim
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX 77058, USA.
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23
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Zhou Y, Ni H, Li M, Sanzari JK, Diffenderfer ES, Lin L, Kennedy AR, Weissman D. Effect of solar particle event radiation and hindlimb suspension on gastrointestinal tract bacterial translocation and immune activation. PLoS One 2012; 7:e44329. [PMID: 23028522 PMCID: PMC3446907 DOI: 10.1371/journal.pone.0044329] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Accepted: 08/01/2012] [Indexed: 01/26/2023] Open
Abstract
The environmental conditions that could lead to an increased risk for the development of an infection during prolonged space flight include: microgravity, stress, radiation, disturbance of circadian rhythms, and altered nutritional intake. A large body of literature exists on the impairment of the immune system by space flight. With the advent of missions outside the Earth's magnetic field, the increased risk of adverse effects due to exposure to radiation from a solar particle event (SPE) needs to be considered. Using models of reduced gravity and SPE radiation, we identify that either 2 Gy of radiation or hindlimb suspension alone leads to activation of the innate immune system and the two together are synergistic. The mechanism for the transient systemic immune activation is a reduced ability of the GI tract to contain bacterial products. The identification of mechanisms responsible for immune dysfunction during extended space missions will allow the development of specific countermeasures.
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Affiliation(s)
- Yu Zhou
- Division of Infectious Diseases, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Houping Ni
- Division of Infectious Diseases, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Minghong Li
- Division of Infectious Diseases, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Jenine K. Sanzari
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Eric S. Diffenderfer
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Liyong Lin
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Ann R. Kennedy
- Department of Radiation Oncology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Drew Weissman
- Division of Infectious Diseases, Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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24
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Hu S, Cucinotta FA. Characterization of the radiation-damaged precursor cells in bone marrow based on modeling of the peripheral blood granulocytes response. HEALTH PHYSICS 2011; 101:67-78. [PMID: 21617393 DOI: 10.1097/hp.0b013e31820dba65] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Bone marrow failure is the major cause of radiation lethality in mammals. Since bone marrow is distributed heterogeneously within trabecular spongiosa encased in a cortex of cortical bone, it is very difficult to measure the extent of the radiation damage directly. However, indirect consequences of damage to marrow, such as reductions in peripheral blood cell counts, are easily measured. In this paper, the authors investgate a mathematical model of the granulopoiesis system that provides quantitative relationships between reductions in peripheral blood cells and the bone marrow precursor cells following radiation exposure. A coarse-grained architecture of cellular replication and production as well as a mechanism for implicit regulation used in this model are discussed. The model is based on previous investigations of rodents. The authors test how well the model matches, in the principal dynamic regime of hematopoiesis, experimental data on large animals as well as empirical data on humans following radiation exposure. Due to its ability to infer, albeit indirectly, radiation damage to bone marrow, this model will provide a useful computational tool in radiation accident management, military operations involving nuclear warfare, radiation therapy, and space radiation risk assessment.
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Affiliation(s)
- Shaowen Hu
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX 77058, USA
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25
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Stisova V, Abele WH, Thompson KH, Bennett PV, Sutherland BM. Response of primary human fibroblasts exposed to solar particle event protons. Radiat Res 2011; 176:217-25. [PMID: 21557667 DOI: 10.1667/rr2490.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Solar particle events (SPEs) present a major radiation-related risk for manned exploratory missions in deep space. Within a short period the astronauts may absorb doses that engender acute effects, in addition to the risk of late effects, such as the induction of cancer. Using primary human cells, we studied clonogenic survival and the induction of neoplastic transformation after exposure to a worst case scenario SPE. We simulated such an SPE with monoenergetic protons (50, 100, 1000 MeV) delivered at a dose rate of 1.65 cGy min⁻¹ in a dose range from 0 to 3 Gy. For comparison, we exposed the cells to a high dose rate of 33.3 cGy min⁻¹. X rays (100 kVp, 8 mA, 1.7 mm Al filter) were used as a reference radiation. Overall, we observed a significant sparing effect of the SPE dose rate on cell survival. High-dose-rate protons were also more efficient in induction of transformation in the dose range below 30 cGy. However, as dose accumulated at high dose rate, the transformation levels declined, while at the SPE dose rate, the number of transformants continued to increase up to about 1 Gy. These findings suggest that considering dose-rate effects may be important in evaluating the biological effects of exposure to space radiation. Our analyses of the data based on particle fluence showed that lethality and transforming potential per particle clearly increased with increasing linear energy transfer (LET) and thus with the decreasing energy of protons. Further, we found that the biological response was determined not only by LET but also type of radiation, e.g. particles and photons. This suggests that using γ or X rays may not be ideal for assessing risk associated with SPE exposures.
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Affiliation(s)
- Viktorie Stisova
- Biology Department, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
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26
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Ni H, Balint K, Zhou Y, Gridley DS, Maks C, Kennedy AR, Weissman D. Effect of solar particle event radiation on gastrointestinal tract bacterial translocation and immune activation. Radiat Res 2011; 175:485-92. [PMID: 21294608 PMCID: PMC3572900 DOI: 10.1667/rr2373.1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Space flight conditions within the protection of Earth's gravitational field have been shown to alter immune responses, which could lead to potentially detrimental pathology. An additional risk of extended space travel outside the Earth's gravitational field is the effect of solar particle event (SPE) radiation exposure on the immune system. Organisms that could lead to infection include endogenous, latent viruses, colonizing pathogenics, and commensals, as well as exogenous microbes present in the spacecraft or other astronauts. In this report, the effect of SPE-like radiation on containment of commensal bacteria and the innate immune response induced by its breakdown was investigated at the radiation energies, doses and dose rates expected during an extravehicular excursion outside the Earth's gravitational field. A transient increase in serum lipopolysaccharide was observed 1 day after irradiation and was accompanied by an increase in acute-phase reactants and circulating proinflammatory cytokines, indicating immune activation. Baseline levels were reestablished by 5 days postirradiation. These findings suggest that astronauts exposed to SPE radiation could have impaired containment of colonizing bacteria and associated immune activation.
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Affiliation(s)
- Houping Ni
- Division of Infectious Diseases, Department of Medicine
| | - Klara Balint
- Division of Infectious Diseases, Department of Medicine
| | - Yu Zhou
- Division of Infectious Diseases, Department of Medicine
| | - Daila S. Gridley
- Department of Radiation Medicine, Loma Linda University & Medical Center, Loma Linda, California 92354
| | - Casey Maks
- Department of Radiation Oncology, University of Pennsylvania, 3610 Hamilton Walk, Philadelphia, Pennsylvania 19104
| | - Ann R. Kennedy
- Department of Radiation Oncology, University of Pennsylvania, 3610 Hamilton Walk, Philadelphia, Pennsylvania 19104
| | - Drew Weissman
- Division of Infectious Diseases, Department of Medicine
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27
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Bahadori AA, Van Baalen M, Shavers MR, Dodge C, Semones EJ, Bolch WE. The effect of anatomical modeling on space radiation dose estimates: a comparison of doses for NASA phantoms and the 5th, 50th, and 95th percentile male and female astronauts. Phys Med Biol 2011; 56:1671-94. [PMID: 21346276 DOI: 10.1088/0031-9155/56/6/010] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The National Aeronautics and Space Administration (NASA) performs organ dosimetry and risk assessment for astronauts using model-normalized measurements of the radiation fields encountered in space. To determine the radiation fields in an organ or tissue of interest, particle transport calculations are performed using self-shielding distributions generated with the computer program CAMERA to represent the human body. CAMERA mathematically traces linear rays (or path lengths) through the computerized anatomical man (CAM) phantom, a computational stylized model developed in the early 1970s with organ and body profiles modeled using solid shapes and scaled to represent the body morphometry of the 1950 50th percentile (PCTL) Air Force male. With the increasing use of voxel phantoms in medical and health physics, a conversion from a mathematical-based to a voxel-based ray-tracing algorithm is warranted. In this study, the voxel-based ray tracer (VoBRaT) is introduced to ray trace voxel phantoms using a modified version of the algorithm first proposed by Siddon (1985 Med. Phys. 12 252-5). After validation, VoBRAT is used to evaluate variations in body self-shielding distributions for NASA phantoms and six University of Florida (UF) hybrid phantoms, scaled to represent the 5th, 50th, and 95th PCTL male and female astronaut body morphometries, which have changed considerably since the inception of CAM. These body self-shielding distributions are used to generate organ dose equivalents and effective doses for five commonly evaluated space radiation environments. It is found that dosimetric differences among the phantoms are greatest for soft radiation spectra and light vehicular shielding.
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Affiliation(s)
- Amir A Bahadori
- Department of Nuclear and Radiological Engineering, University of Florida, Gainesville, FL 32611, USA
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28
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Hu S, Cucinotta FA. A cell kinetic model of granulopoiesis under radiation exposure: extension from rodents to canines and humans. RADIATION PROTECTION DOSIMETRY 2011; 143:207-213. [PMID: 21196459 DOI: 10.1093/rpd/ncq520] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
As significant ionising radiation exposure will occur during prolonged space travel in future, it is essential to understand their adverse effects on the radiosensitive organ systems that are important for immediate survival of humans, e.g. the haematopoietic system. In this paper, a biomathematical model of granulopoiesis is used to analyse the granulocyte changes seen in the blood of mammalians under acute and continuous radiation exposure. This is one of a set of haematopoietic models that have been successfully utilised to simulate and interpret the experimental data of acute and chronic radiation on rodents. Extension to canine and human systems indicates that the results of the model are consistent with the cumulative experimental and empirical data from various sources, implying the potential to integrate them into one united model system to monitor the haematopoietic response of various species under irradiation. The suppression of granulocytes' level of a space traveller under chronic stress of low-dose irradiation as well as the granulopoietic response when encountering a historically large solar particle event is also discussed.
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Affiliation(s)
- Shaowen Hu
- Division of Space Life Sciences, Universities Space Research Association, Houston, TX 77058, USA.
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29
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Ennis CP, Kaiser RI. Mechanistical studies on the electron-induced degradation of polymers: polyethylene, polytetrafluoroethylene, and polystyrene. Phys Chem Chem Phys 2010; 12:14884-901. [PMID: 20978662 DOI: 10.1039/c0cp00493f] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Mechanisms of the electron-induced degradation of three polymers utilized in aerospace applications (polyethylene (PE), polytetrafluoroethylene (PTFE), and polystyrene (PS)) were examined over a temperature range of 10 K to 300 K at ultra high vacuum conditions (∼10(-11) Torr). These processes simulate the interaction of secondary electrons generated in the track of galactic cosmic ray particles in the near-Earth space environment with polymer material. The chemical alterations at the macromolecular level were monitored on-line and in situ by Fourier-transform infrared spectroscopy and mass spectrometry. These data yielded important information on the temperature dependent kinetics on the formation of, for instance, trans-vinylene groups (-CH=CH-) in PE, benzene (C(6)H(6)) production in PS, fluorinated trans-vinylene (-CF=CF-) and terminal vinyl (-CF=CF(2)) groups in PTFE together with molecular hydrogen release in PE and PS. Additional data on the radiation-induced development of unsaturated, conjugated bonds were collected via UV-vis spectroscopy. Temperature dependent G-values for trans-vinylene formation (G(-CH=CH-) ≈ 25-2.5 × 10(-4) units (100 eV)(-1) from 10-300 K) and molecular hydrogen evolution (G(H(2)) ≈ 8-80 × 10(-5) molecules (100 eV)(-1) from 10-300 K) for irradiated PE were calculated to quantify the degree of polymer degradation following electron irradiation. These values are typically two to three orders of magnitude less than G-values previously published for the irradiation of polymers with energetic particles of higher mass.
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Affiliation(s)
- Courtney P Ennis
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA
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30
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Ware JH, Sanzari J, Avery S, Sayers C, Krigsfeld G, Nuth M, Wan XS, Rusek A, Kennedy AR. Effects of proton radiation dose, dose rate and dose fractionation on hematopoietic cells in mice. Radiat Res 2010; 174:325-30. [PMID: 20726731 DOI: 10.1667/rr1979.1] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The present study evaluated the acute effects of radiation dose, dose rate and fractionation as well as the energy of protons in hematopoietic cells of irradiated mice. The mice were irradiated with a single dose of 51.24 MeV protons at a dose of 2 Gy and a dose rate of 0.05-0.07 Gy/min or 1 GeV protons at doses of 0.1, 0.2, 0.5, 1, 1.5 and 2 Gy delivered in a single dose at dose rates of 0.05 or 0.5 Gy/min or in five daily dose fractions at a dose rate of 0.05 Gy/min. Sham-irradiated animals were used as controls. The results demonstrate a dose-dependent loss of white blood cells (WBCs) and lymphocytes by up to 61% and 72%, respectively, in mice irradiated with protons at doses up to 2 Gy. The results also demonstrate that the dose rate, fractionation pattern and energy of the proton radiation did not have significant effects on WBC and lymphocyte counts in the irradiated animals. These results suggest that the acute effects of proton radiation on WBC and lymphocyte counts are determined mainly by the radiation dose, with very little contribution from the dose rate (over the range of dose rates evaluated), fractionation and energy of the protons.
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Affiliation(s)
- J H Ware
- Department of Radiation Oncology, Division of Oncology Research, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6072, USA.
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31
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Wambi CO, Sanzari JK, Sayers CM, Nuth M, Zhou Z, Davis J, Finnberg N, Lewis-Wambi JS, Ware JH, El-Deiry WS, Kennedy AR. Protective effects of dietary antioxidants on proton total-body irradiation-mediated hematopoietic cell and animal survival. Radiat Res 2009; 172:175-86. [PMID: 19630522 DOI: 10.1667/rr1708.1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Abstract Dietary antioxidants have radioprotective effects after gamma-radiation exposure that limit hematopoietic cell depletion and improve animal survival. The purpose of this study was to determine whether a dietary supplement consisting of l-selenomethionine, vitamin C, vitamin E succinate, alpha-lipoic acid and N-acetyl cysteine could improve survival of mice after proton total-body irradiation (TBI). Antioxidants significantly increased 30-day survival of mice only when given after irradiation at a dose less than the calculated LD(50/30); for these data, the dose-modifying factor (DMF) was 1.6. Pretreatment of animals with antioxidants resulted in significantly higher serum total white blood cell, polymorphonuclear cell and lymphocyte cell counts at 4 h after 1 Gy but not 7.2 Gy proton TBI. Antioxidants significantly modulated plasma levels of the hematopoietic cytokines Flt-3L and TGFbeta1 and increased bone marrow cell counts and spleen mass after TBI. Maintenance of the antioxidant diet resulted in improved recovery of peripheral leukocytes and platelets after sublethal and potentially lethal TBI. Taken together, oral supplementation with antioxidants appears to be an effective approach for radioprotection of hematopoietic cells and improvement of animal survival after proton TBI.
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Affiliation(s)
- Chris O Wambi
- Department of Radiation Oncology, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
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32
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Gridley DS, Coutrakon GB, Rizvi A, Bayeta EJM, Luo-Owen X, Makinde AY, Baqai F, Koss P, Slater JM, Pecaut MJ. Low-Dose Photons Modify Liver Response to Simulated Solar Particle Event Protons. Radiat Res 2008; 169:280-7. [DOI: 10.1667/rr1155.1] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2007] [Accepted: 11/08/2007] [Indexed: 01/18/2023]
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34
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Hellweg CE, Baumstark-Khan C. Getting ready for the manned mission to Mars: the astronauts' risk from space radiation. Naturwissenschaften 2007; 94:517-26. [PMID: 17235598 DOI: 10.1007/s00114-006-0204-0] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2006] [Revised: 10/31/2006] [Accepted: 11/01/2006] [Indexed: 01/25/2023]
Abstract
Space programmes are shifting towards planetary exploration and, in particular, towards missions by human beings to the Moon and to Mars. Radiation is considered to be one of the major hazards for personnel in space and has emerged as the most critical issue to be resolved for long-term missions both orbital and interplanetary. The two cosmic sources of radiation that could impact a mission outside the Earth's magnetic field are solar particle events (SPE) and galactic cosmic rays (GCR). Exposure to the types of ionizing radiation encountered during space travel may cause a number of health-related problems, but the primary concern is related to the increased risk of cancer induction in astronauts. Predictions of cancer risk and acceptable radiation exposure in space are extrapolated from minimal data and are subject to many uncertainties. The paper describes present-day estimates of equivalent doses from GCR and solar cosmic radiation behind various shields and radiation risks for astronauts on a mission to Mars.
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Affiliation(s)
- Christine E Hellweg
- DLR, Institut für Luft-und Raumfahrtmedizin, Strahlenbiologie, 51147, Cologne, Germany
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35
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Spillantini P, Casolino M, Durante M, Mueller-Mellin R, Reitz G, Rossi L, Shurshakov V, Sorbi M. Shielding from cosmic radiation for interplanetary missions: Active and passive methods. RADIAT MEAS 2007. [DOI: 10.1016/j.radmeas.2006.04.028] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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36
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Kim MHY, Cucinotta FA, Wilson JW. Mean occurrence frequency and temporal risk analysis of solar particle events. RADIAT MEAS 2006. [DOI: 10.1016/j.radmeas.2005.11.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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37
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Rabbow E, Stojicic N, Walrafen D, Baumstark-Khan C, Rettberg P, Schulze-Varnholt D, Franz M, Reitz G. The SOS-LUX-TOXICITY-Test on the International Space Station. Res Microbiol 2005; 157:30-6. [PMID: 16431084 DOI: 10.1016/j.resmic.2005.08.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2005] [Revised: 08/16/2005] [Accepted: 08/17/2005] [Indexed: 11/15/2022]
Abstract
For the safety of astronauts and to ensure the stability and integrity of the genome of microorganisms and plants used in bioregenerative life support systems, it is important to improve our knowledge of the combined action of (space) radiation and microgravity. The SOS-LUX-TOXICITY test, as part of the TRIPLE-LUX project (accepted for flight at Biolab in Columbus on the International Space Station, (ISS)), will provide an estimation of the health risk resulting from exposure of astronauts to the radiation environment of space in microgravity. The project will: (i) increase our knowledge of biological/health threatening action of space radiation and enzymatic DNA repair; (ii) uncover cellular mechanisms of synergistic interaction of microgravity and space radiation; (iii) provide specified biosensors for spacecraft milieu examination; and (iv) provide experimental data on stability and integrity of bacterial DNA in spacecrafts. In the bacterial biosensor "SOS-LUX-Test" developed at DLR (patent), bacteria are transformed with the pBR322-derived plasmid pPLS-1 or the similar, advanced plasmid SWITCH, both carrying the promoterless lux operon of Photobacterium leiognathi as the reporter element controlled by a DNA damage-dependent SOS promoter as sensor element. A short description of the space experiment is given, and the current status of adaptation of the SOS-LUX-Test to the ISS, i.e. first results of sterilization, biocompatibility and functional tests performed with the already available hardware and bread board model of the automated space hardware under development, is described here.
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Affiliation(s)
- Elke Rabbow
- DLR, Institut für Luft- und Raumfahrtmedizin, Strahlenbiologie, 51117 Köln, Germany.
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38
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De Angelis G, Anderson BM, Atwell W, Nealy JE, Qualls GD, Wilson JW. Astronaut EVA exposure estimates from CAD model spacesuit geometry. JOURNAL OF RADIATION RESEARCH 2004; 45:1-9. [PMID: 15133283 DOI: 10.1269/jrr.45.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Ongoing assembly and maintenance activities at the International Space Station (ISS) require much more extravehicular activity (EVA) than did the earlier U.S. Space Shuttle missions. It is thus desirable to determine and analyze, and possibly foresee, as accurately as possible what radiation exposures crew members involved in EVAs will experience in order to minimize risks and to establish exposure limits that must not to be exceeded. A detailed CAD model of the U.S. Space Shuttle EVA Spacesuit, developed at NASA Langley Research Center (LaRC), is used to represent the directional shielding of an astronaut; it has detailed helmet and backpack structures, hard upper torso, and multilayer space suit fabric material. The NASA Computerized Anatomical Male and Female (CAM and CAF) models are used in conjunction with the space suit CAD model for dose evaluation within the human body. The particle environments are taken from the orbit-averaged NASA AP8 and AE8 models at solar cycle maxima and minima. The transport of energetic particles through space suit materials and body tissue is calculated by using the NASA LaRC HZETRN code for hadrons and a recently developed deterministic transport code, ELTRN, for electrons. The doses within the CAM and CAF models are determined from energy deposition at given target points along 968 directional rays convergent on the points and are evaluated for several points on the skin and within the body. Dosimetric quantities include contributions from primary protons, light ions, and electrons, as well as from secondary brehmsstrahlung and target fragments. Directional dose patterns are displayed as rays and on spherical surfaces by the use of a color relative intensity representation.
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Wilson JW, Clowdsley MS, Cucinotta FA, Tripathi RK, Nealy JE, De Angelis G. Deep space environments for human exploration. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2004; 34:1281-7. [PMID: 15880915 DOI: 10.1016/j.asr.2003.10.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Mission scenarios outside the Earth's protective magnetic shield are being studied. Included are high usage assets in the near-Earth environment for casual trips, for research, and for commercial/operational platforms, in which career exposures will be multi-mission determined over the astronaut's lifetime. The operational platforms will serve as launching points for deep space exploration missions, characterized by a single long-duration mission during the astronaut's career. The exploration beyond these operational platforms will include missions to planets, asteroids, and planetary satellites. The interplanetary environment is evaluated using convective diffusion theory. Local environments for each celestial body are modeled by using results from the most recent targeted spacecraft, and integrated into the design environments. Design scenarios are then evaluated for these missions. The underlying assumptions in arriving at the model environments and their impact on mission exposures within various shield materials will be discussed.
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Affiliation(s)
- J W Wilson
- NASA Langley Research Center, Hampton, VA 23681-2199, USA.
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Kiefer J. Chairman's introduction: mechanisms, models and experiments in space radiation research. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2004; 34:1278-80. [PMID: 15880914 DOI: 10.1016/j.asr.2003.04.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Radiation risk estimate in space is a moral obligation and a scientific challenge requiring the combined efforts of physicists and biologists. This introductory paper presents some thoughts about problems to be solved and the possible directions of research. It stresses the necessity of cooperation across disciplines and the combination of space and ground based investigations.
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Affiliation(s)
- Juergen Kiefer
- Strahlenzentrum, Justus-Liebig-University, Giessen, Germany.
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41
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Ballarini F, Biaggi M, De Biaggi L, Ferrari A, Ottolenghi A, Panzarasa A, Paretzke HG, Pelliccioni M, Sala P, Scannicchio D, Zankl M. Role of shielding in modulating the effects of solar particle events: Monte Carlo calculation of absorbed dose and DNA complex lesions in different organs. ADVANCES IN SPACE RESEARCH : THE OFFICIAL JOURNAL OF THE COMMITTEE ON SPACE RESEARCH (COSPAR) 2004; 34:1338-46. [PMID: 15881774 DOI: 10.1016/j.asr.2003.08.055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Distributions of absorbed dose and DNA clustered damage yields in various organs and tissues following the October 1989 solar particle event (SPE) were calculated by coupling the FLUKA Monte Carlo transport code with two anthropomorphic phantoms (a mathematical model and a voxel model), with the main aim of quantifying the role of the shielding features in modulating organ doses. The phantoms, which were assumed to be in deep space, were inserted into a shielding box of variable thickness and material and were irradiated with the proton spectra of the October 1989 event. Average numbers of DNA lesions per cell in different organs were calculated by adopting a technique already tested in previous works, consisting of integrating into "condensed-history" Monte Carlo transport codes--such as FLUKA--yields of radiobiological damage, either calculated with "event-by-event" track structure simulations, or taken from experimental works available in the literature. More specifically, the yields of "Complex Lesions" (or "CL", defined and calculated as a clustered DNA damage in a previous work) per unit dose and DNA mass (CL Gy-1 Da-1) due to the various beam components, including those derived from nuclear interactions with the shielding and the human body, were integrated in FLUKA. This provided spatial distributions of CL/cell yields in different organs, as well as distributions of absorbed doses. The contributions of primary protons and secondary hadrons were calculated separately, and the simulations were repeated for values of Al shielding thickness ranging between 1 and 20 g/cm2. Slight differences were found between the two phantom types. Skin and eye lenses were found to receive larger doses with respect to internal organs; however, shielding was more effective for skin and lenses. Secondary particles arising from nuclear interactions were found to have a minor role, although their relative contribution was found to be larger for the Complex Lesions than for the absorbed dose, due to their higher LET and thus higher biological effectiveness.
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Affiliation(s)
- F Ballarini
- Dipartimento di Fisica Nucleare e Teorica, Università degli Studi di Pavia, Pavia, Italy.
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42
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Wilson JW, Kim MHY, De Angelis G, Cucinotta FA, Yoshizawa N, Badavi FF. Implementation of Gy-Eq for deterministic effects limitation in shield design. JOURNAL OF RADIATION RESEARCH 2002; 43 Suppl:S103-S106. [PMID: 12793740 DOI: 10.1269/jrr.43.s103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The NCRP has recently defined RBE values and a new quantity (Gy-Eq) for use in estimation of deterministic effects in space shielding and operations. The NCRP's RBE for neutrons is left ambiguous and not fully defined. In the present report we will suggest a complete definition of neutron RBE consistent with the NCRP recommendations and evaluate attenuation properties of deterministic effects (Gy-Eq) in comparison with other dosimetric quantities.
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Affiliation(s)
- John W Wilson
- NASA Langley Research Center, Hampton, VA 23681, USA.
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43
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Benton ER, Benton EV. Space radiation dosimetry in low-Earth orbit and beyond. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION B, BEAM INTERACTIONS WITH MATERIALS AND ATOMS 2001; 184:255-294. [PMID: 11863032 DOI: 10.1016/s0168-583x(01)00748-0] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Space radiation dosimetry presents one of the greatest challenges in the discipline of radiation protection. This is a result of both the highly complex nature of the radiation fields encountered in low-Earth orbit (LEO) and interplanetary space and of the constraints imposed by spaceflight on instrument design. This paper reviews the sources and composition of the space radiation environment in LEO as well as beyond the Earth's magnetosphere. A review of much of the dosimetric data that have been gathered over the last four decades of human space flight is presented. The different factors affecting the radiation exposures of astronauts and cosmonauts aboard the International Space Station (ISS) are emphasized. Measurements made aboard the Mir Orbital Station have highlighted the importance of both secondary particle production within the structure of spacecraft and the effect of shielding on both crew dose and dose equivalent. Roughly half the dose on ISS is expected to come from trapped protons and half from galactic cosmic rays (GCRs). The dearth of neutron measurements aboard LEO spacecraft and the difficulty inherent in making such measurements have led to large uncertainties in estimates of the neutron contribution to total dose equivalent. Except for a limited number of measurements made aboard the Apollo lunar missions, no crew dosimetry has been conducted beyond the Earth's magnetosphere. At the present time we are forced to rely on model-based estimates of crew dose and dose equivalent when planning for interplanetary missions, such as a mission to Mars. While space crews in LEO are unlikely to exceed the exposure limits recommended by such groups as the NCRP, dose equivalents of the same order as the recommended limits are likely over the course of a human mission to Mars.
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Affiliation(s)
- E R Benton
- Eril Research, Inc., San Rafael, CA 94915-0788, USA.
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45
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Anderson BM, Nealy JE, Qualls G, Staritz PJ, Wilson J, Kim MHY, Cucinotta FA, Atwell W, De Angelis G, Ware J, Persans AE. Shuttle Spacesuit (Radiation) Model Development. ACTA ACUST UNITED AC 2001. [DOI: 10.4271/2001-01-2368] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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