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Sagehashi K, Haga Y, Takahira S, Tanabe M, Nakamura M, Sota M, Kaga Y, Abe M, Tada N, Chida K. Evaluation of radiation dose to the lens in interventional cardiology physicians before and after dose limit regulation changes. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2024; 44:031512. [PMID: 39142296 DOI: 10.1088/1361-6498/ad6f19] [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: 05/14/2024] [Accepted: 08/14/2024] [Indexed: 08/16/2024]
Abstract
In response to the International Commission on Radiological Protection, which lowered the lens equivalent dose limit, Japan lowered the lens dose limit from 150 mSv y-1to 100 mSv/5 years and 50 mSv y-1, with this new rule taking effect on 1 April 2021. DOSIRIS®is a dosimeter that can accurately measure lens dose. Herein, we investigated lens dose in interventional cardiology physicians 1 year before and after the reduction of the lens dose limit using a neck dosimeter and lens dosimeter measurements. With an increase in the number of cases, both personal dose equivalent at 0.07 mm depth [Hp(0.07), neck dosimeter] and personal dose equivalent at 3 mm depth [Hp(3), lens dosimeter] increased for most of the physicians. The Hp(3) of the lens considering the shielding effect of the Pb glasses using lens dosimeter exceeded 20 mSv y-1for two of the 14 physicians. Protection from radiation dose will become even more important in the future, as these two physicians may experience radiation dose exceeding 100 mSv/5 years. The average dose per procedure increased, but not significantly. There was a strong correlation between the neck dosimeter and lens dosimeter scores, although there was no significant change before and after the lens dose limit was lowered. This correlation was particularly strong for physicians who primarily treated patients. As such, it is possible to infer accurate lens doses from neck doses in physicians who primarily perform diagnostics. However, it is desirable to use a dosimeter that can directly measure Hp(3) because of the high lens dose.
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Affiliation(s)
- Kodai Sagehashi
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
| | - Yoshihiro Haga
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
- Department of Radiology, Sendai Kosei Hospital, 4-15, Hirose-Machi, Aoba-Ku, Sendai, Miyagi 980-0873, Japan
| | - Saki Takahira
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
| | - Mako Tanabe
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
- Disaster Medical Radiology, Division of Disaster Medical Science, International Research Institute of Disaster Science, Tohoku University, 468-1, Aoba, Aramaki, Aoba-Ku, Sendai, Miyagi 980-8572, Japan
| | - Mio Nakamura
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
- Disaster Medical Radiology, Division of Disaster Medical Science, International Research Institute of Disaster Science, Tohoku University, 468-1, Aoba, Aramaki, Aoba-Ku, Sendai, Miyagi 980-8572, Japan
| | - Masahiro Sota
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
- Department of Radiology, Sendai Kosei Hospital, 4-15, Hirose-Machi, Aoba-Ku, Sendai, Miyagi 980-0873, Japan
| | - Yuji Kaga
- Department of Radiology, Sendai Kosei Hospital, 4-15, Hirose-Machi, Aoba-Ku, Sendai, Miyagi 980-0873, Japan
| | - Mitsuya Abe
- Department of Radiology, Sendai Kosei Hospital, 4-15, Hirose-Machi, Aoba-Ku, Sendai, Miyagi 980-0873, Japan
| | - Norio Tada
- Department of Cardiovascular Medicine, Sendai Kousei Hospital, 4-15 Hirose-machi, Aoba-ku, Sendai 980-0873, Japan
| | - Koichi Chida
- Department of Radiological Examination and Technology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-Machi, Aoba-Ku, Sendai, Miyagi 980-8575, Japan
- Disaster Medical Radiology, Division of Disaster Medical Science, International Research Institute of Disaster Science, Tohoku University, 468-1, Aoba, Aramaki, Aoba-Ku, Sendai, Miyagi 980-8572, Japan
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Tang Y, Liang H, Su L, Xue X, Zhan J. Ferroptosis: a new perspective on the pathogenesis of radiation-induced cataracts. Front Public Health 2024; 12:1449216. [PMID: 39220446 PMCID: PMC11363423 DOI: 10.3389/fpubh.2024.1449216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2024] [Accepted: 08/05/2024] [Indexed: 09/04/2024] Open
Abstract
Ionizing radiation is a significant risk factor for cataracts, but the pathogenesis of radiation-induced cataracts remains incompletely understood. Ferroptosis, an iron-dependent form of programmed cell death discovered in recent years, has gained increasing attention for its role in various diseases. This article systematically reviews research progress on ionizing radiation, ferroptosis, age-related cataracts, and radiation-induced cataracts. It proposes the "ferroptosis hypothesis" for the pathogenesis of radiation-induced cataracts. Through ionization and oxidative stress effects, ionizing radiation leads to elevated free iron levels and exacerbated lipid peroxidation in lens cells, activating the ferroptosis pathway and resulting in lens opacity. The involvement of ferroptosis in the development of age-related cataracts suggests that it may also be an important pathogenic mechanism of radiation-induced cataracts. Targeting the ferroptosis pathway may be a novel strategy for preventing and treating radiation-induced cataracts. Furthermore, developing new ferroptosis-specific inhibitors with improved targeting and pharmacokinetic properties is also an essential direction for research on preventing and treating radiation-induced cataracts. The study of ferroptosis provides new insights into the mechanism and management of radiation-induced cataracts, potentially transforming radiation-induced cataracts from "inevitable" to "preventable and treatable."
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Affiliation(s)
| | | | | | - Xiangming Xue
- Division of Radiology and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, China
| | - Jingming Zhan
- Division of Radiology and Environmental Medicine, China Institute for Radiation Protection, Taiyuan, China
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Li M, Deng L, Zhou W, Zhao Y, Wang T, Hao S, Fan S, Deng J, Sun Q. Trends of occupational exposure to ionizing radiation in Central China for the period 2000-2021. Appl Radiat Isot 2024; 208:111283. [PMID: 38484590 DOI: 10.1016/j.apradiso.2024.111283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2023] [Revised: 02/26/2024] [Accepted: 03/08/2024] [Indexed: 04/15/2024]
Abstract
A retrospective analysis of occupational exposure to ionizing radiation from medical uses and industrial uses in the three provinces of Central China from 2000 to 2021 was conducted. The average annual effective dose in medical uses and industrial uses decreased from 2.042 mSv and 2.334 mSv in 2000-2002 to 0.476 mSv and 0.371 mSv in 2021 respectively; the fraction of monitored workers receiving annual dose not exceeding 1 mSv increased from 60.78% and 74.45% in 2000-2002 to 94.20% and 96.85% in 2021 respectively, while receiving annual doses exceeding 20 mSv declined from 1.35% and 1.91% in 2000-2002 to 0.18% and 0.03% in 2021 respectively. The average annual effective dose and NR20 in the period 2000-2021 were relatively high in professional public health institutions (0.955 mSv and 0.004) and hospitals (0.815 mSv and 0.004). In 2021, the average annual effective dose to monitored workers in different occupational categories in medical uses in the three provinces of Central China were in the range of 0.199-0.692 mSv, with interventional radiology received the highest dose and NR20 (0.692 mSv and 0.005); the average annual effective dose ranged from 0.161 to 0.493 mSv in industrial uses, with industrial radiography received the highest dose and NR20 (0.493 mSv and 0.001). Occupational exposure in medical uses and industrial uses declined obviously in Central China, and the groups receiving higher doses are the radiation workers working in hospitals and professional public health institutions, or engaged in interventional radiology, nuclear medicine and industrial radiography, warranting more effective radiation protection measures.
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Affiliation(s)
- Mengxue Li
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing, 100088, China
| | - Lei Deng
- Institute of Occupational Medicine of Jiangxi, Nanchang, 330006, China
| | - Wenshan Zhou
- Hubei Center for Disease Control and Prevention, Wuhan, 430079, China
| | - Yanfang Zhao
- Third People's Hospital of Henan Province, Henan Hospital for Occupational Diseases, Zhengzhou, 450052, China
| | - Tuo Wang
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing, 100088, China
| | - Shuxia Hao
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing, 100088, China
| | - Shengnan Fan
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing, 100088, China
| | - Jun Deng
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing, 100088, China.
| | - Quanfu Sun
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing, 100088, China
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Mothersill C, Seymour C, Cocchetto A, Williams D. Factors Influencing Effects of Low-dose Radiation Exposure. HEALTH PHYSICS 2024; 126:296-308. [PMID: 38526248 DOI: 10.1097/hp.0000000000001816] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
ABSTRACT It is now well accepted that the mechanisms induced by low-dose exposures to ionizing radiation (LDR) are different from those occurring after high-dose exposures. However, the downstream effects of these mechanisms are unclear as are the quantitative relationships between exposure, effect, harm, and risk. In this paper, we will discuss the mechanisms known to be important with an overall emphasis on how so-called "non-targeted effects" (NTE) communicate and coordinate responses to LDR. Targeted deposition of ionizing radiation energy in cells causing DNA damage is still regarded as the dominant trigger leading to all downstream events whether targeted or non-targeted. We regard this as an over-simplification dating back to formal target theory. It ignores that last 100 y of biological research into stress responses and signaling mechanisms in organisms exposed to toxic substances, including ionizing radiation. We will provide evidence for situations where energy deposition in cellular targets alone cannot be plausible as a mechanism for LDR effects. An example is where the energy deposition takes place in an organism not receiving the radiation dose. We will also discuss how effects after LDR depend more on dose rate and radiation quality rather than actual dose, which appears rather irrelevant. Finally, we will use recent evidence from studies of cataract and melanoma induction to suggest that after LDR, post-translational effects, such as protein misfolding or defects in energy metabolism or mitochondrial function, may dominate the etiology and progression of the disease. A focus on such novel pathways may open the way to successful prophylaxis and development of new biomarkers for better risk assessment after low dose exposures.
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Affiliation(s)
- Carmel Mothersill
- Department of Biology, McMaster University, 1280 Main St., Hamilton, ON, Canada L8S 4L8
| | - Colin Seymour
- Department of Biology, McMaster University, 1280 Main St., Hamilton, ON, Canada L8S 4L8
| | - Alan Cocchetto
- The National CFIDS Foundation, 285 Beach Ave., Hull, MA 02045
| | - David Williams
- Cambridge University, The Old Schools, Trinity Lane, Cambridge CB2 1TN, United Kingdom
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Serna Santos J, Kaasalainen T, Laukontaus S, Björkman P, Heinola I, Laine M, Vikatmaa P, Pekkarinen A, Venermo M, Aho P. The Effect of a Suspended Radiation Protection System on Occupational Radiation Doses During Infrarenal EVAR Procedures: A Randomised Controlled Study. Eur J Vasc Endovasc Surg 2024; 67:435-443. [PMID: 37611731 DOI: 10.1016/j.ejvs.2023.08.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 07/06/2023] [Accepted: 08/15/2023] [Indexed: 08/25/2023]
Abstract
OBJECTIVE To compare the protective effect of Zero Gravity (ZG) with conventional radiation protection during endovascular aneurysm repair (EVAR). Secondly, user experience was surveyed with a questionnaire on ergonomics. METHODS This was a single centre, prospective, randomised, two arm trial where 71 consecutive elective infrarenal EVAR procedures were randomised into two groups: (1) operator using ZG and assistant using conventional protection (n = 36), and (2) operator and assistant using conventional radiation protection (n = 35). A movable floor unit ZG system consists of a lead shield (1.0 mm Pb equivalent) for the front of the body and 0.5 mm Pb equivalent acrylic shielding for the head and neck. The ZG also includes arm flaps of 0.5 mm Pb equivalent covering the arm up to the elbow. Deep dose equivalent values, Hp(10) were measured with direct ion storage dosimeters (DIS) placed on various anatomical regions of the operator (axilla, chest, abdomen, and lower leg). Personal dose equivalent values, Hp(3) to eye lenses were measured in the operating and assisting surgeon using thermoluminescence dosimeters. The study was registered at the US National Institute of Health #NCT04078165. RESULTS Protection with the standard protection was superior in chest (0.0 vs. 0.1 μSv), abdomen (0.0 vs. 0.6 μSv), and lower leg (0.4 vs. 2.2 μSv) (p < .001). On the other hand, the ZG system yielded better shielding for the axilla (1.5 vs. 0.0 μSv) and eyes (6.3 vs. 1.1 μSv) of the operator. The use of ZG hampered the deployment of ancillary shields, which is particularly relevant for protection of the assisting surgeon. Users found ZG more cumbersome than conventional garments, it also impaired communication and reduced field of view. CONCLUSION Both ZG and conventional radiation protection reduced radiation exposure. Conventional protection allows better manoeuvrability at the price of wider exposure of the upper arm and axilla. ZG indirectly impaired protection of the assistant.
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Affiliation(s)
- Juan Serna Santos
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland.
| | - Touko Kaasalainen
- HUS Diagnostic Centre, Radiology, University of Helsinki and Helsinki University Hospital, Finland
| | - Sani Laukontaus
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
| | - Patrick Björkman
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
| | - Ivika Heinola
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
| | - Matti Laine
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
| | - Pirkka Vikatmaa
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
| | - Antti Pekkarinen
- Radiation Practices Regulation, Radiation and Nuclear Safety Authority (STUK), Helsinki, Finland; Department of Medical Physics, Kymsote, Kymenlaakso Central Hospital
| | - Maarit Venermo
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
| | - Pekka Aho
- Department of Vascular Surgery, University of Helsinki and Helsinki University Hospital, Finland
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Zhang Y, Feng B, Ning H, Dai G, Su W, Lu H, Hu P. One-hole split endoscope technique for migrated lumbar disc herniation: a single-centre, retrospective study of a novel technique. J Orthop Surg Res 2023; 18:483. [PMID: 37408054 DOI: 10.1186/s13018-023-03967-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Accepted: 06/30/2023] [Indexed: 07/07/2023] Open
Abstract
BACKGROUND Lumbar disc herniation (LDH) is one of the most common diseases of the spine, and migrated LDH is a more serious type, associated with nerve root function injury or abnormality. Regarding the increasing surgery adoption of treating migrated LDH, we aimed to investigate the clinical efficacy and safety of discectomy with a novel technique-one-hole split endoscope (OSE) technique. METHODS This was a retrospective analysis of migrated LDH treated between December 2020 and September 2021. Hospitalization time, operative duration, intraoperative blood loss, number of fluoroscopy exposures, incision length, postoperative facet preservation rate, number of excellent-good cases, lower back and leg visual analogue score (VAS), Oswestry Disability Index (ODI) and surgical complications were compared between high-grade migration group (82 cases) and low-grade migration group (148 cases). The Macnab criteria was used to evaluate the clinical outcome. The Shapiro‒Wilk test was used to test measurement data, and the χ2 test was used to test counting data. RESULTS There was no significant difference in hospitalization time, operative duration, intraoperative blood loss, number of fluoroscopy exposures, incision length or postoperative facet preservation rate between the two groups by independent sample t test or nonparametric test. At any time point, the lower back and leg VAS and ODI of the two groups were significantly improved compared to those before the operation, but there was no significant difference between the two groups at the same time point by two-way repeated measures ANOVA. There were two cases of postoperative nerve root stimulation symptoms in the high-grade migration group and three cases in the low-grade migration group. There was one patient reoperated in the high-grade migration group. There was no significant difference in number of excellent-good cases between the two groups. The overall excellent-good rate was 89.6%. CONCLUSION The OSE technique has the advantages of less trauma, faster recovery, complete removal of the nucleus pulposus and a satisfactory early clinical efficacy in the treatment of migrated LDH.
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Affiliation(s)
- Yuhong Zhang
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China
| | - Bo Feng
- Department of Neurology, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China
| | - Huaxiu Ning
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China
| | - Guohua Dai
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China
| | - Weiliang Su
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China
| | - Huaiwang Lu
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China
| | - Peng Hu
- Department of Spine Surgery, Binzhou Medical University Hospital, No. 661, Huanghe 2th Road, Binzhou, 256603, Shandong, China.
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Kaasalainen T, Pekkarinen A, Kylänpää L, Rainio M, Tenca A, Jokelainen K, Barner-Rasmussen N, Puustinen L, Udd M, Lindström O. Occupational radiation dose from gastrointestinal endoscopy procedures with special emphasis on eye lens doses in endoscopic retrograde cholangiopancreatography. Endosc Int Open 2023; 11:E237-E246. [PMID: 36910845 PMCID: PMC9995179 DOI: 10.1055/a-2022-2663] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 01/25/2023] [Indexed: 03/14/2023] Open
Abstract
Background and study aims Endoscopic retrograde cholangiopancreatography (ERCP) procedures may result in remarkable radiation doses to patients and staff. The aim of this prospective study was to determine occupational exposures in gastrointestinal endoscopy procedures, with a special emphasis on eye lens dose in ERCP. Methods Altogether 604 fluoroscopy-guided procedures, of which 560 were ERCPs belonging to four American Society for Gastrointestinal Endoscopy procedural complexity levels, were performed using two fluoroscopy systems. Personal deep-dose equivalent H p (10), shallow-dose equivalent H p (0.07), and eye lens dose equivalent H p (3) of eight interventionists and H p (3) for two nurse dosimeters were measured. Thereafter, conversion coefficients from kerma-area product (KAP) for H p (10), H p (0.07), and H p (3) were determined and dose equivalents per procedure to an operator and assisting staff were estimated. Further, mean conversion factors from H p (10) and H p (0.07) to H p (3) were calculated. Results The median KAP in ERCP was 1.0 Gy·cm 2 , with mobile c-arm yielding higher doses than a floor-mounted device ( P < 0.001). The median H p (3) per ERCP was estimated to be 0.6 µSv (max. 12.5 µSv) and 0.4 µSv (max. 12.2 µSv) for operators and assisting staff, respectively. The median H p (10) and H p (0.07) per procedure ranged from 0.6 to 1.8 µSv. ERCP procedural complexity level ( P ≤ 0.002) and interventionist ( P < 0.001) affected dose equivalents. Conclusions Occupational dose limits are unlikely to be exceeded in gastrointestinal endoscopy practice when following radiation-hygienic working methods and focusing on dose optimization. The eye lens dose equivalent H p (3) may be estimated with sufficient agreement from the H p (10) and H p (0.07).
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Affiliation(s)
- Touko Kaasalainen
- HUS Diagnostic Center, Radiology, University of Helsinki and Helsinki University Hospital, Finland
| | - Antti Pekkarinen
- Radiation and Nuclear Safety Authority - STUK, Helsinki, Finland.,Department of Physics, University of Helsinki, Helsinki, Finland.,Department of Medical Physics, Kymsote, Kymenlaakso Central Hospital, Helsinki, Finland
| | - Leena Kylänpää
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Mia Rainio
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Andrea Tenca
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Kalle Jokelainen
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Nina Barner-Rasmussen
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Lauri Puustinen
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Marianne Udd
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
| | - Outi Lindström
- HUS Abdominal Center, Endoscopy Department, University of Helsinki and Helsinki University Hospital, Finland
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Abstract
PURPOSE Cataract (opacification of the ocular lens) is a typical tissue reaction (deterministic effect) following ionizing radiation exposure, for which prevention dose limits have been recommended in the radiation protection system. Manifestations of radiation cataracts can vary among individuals, but such potential individual responses remain uncharacterized. Here we review relevant literature and discuss implications for radiation protection. This review assesses evidence for significant modification of radiation-induced cataractogenesis by age at exposure, sex and genetic factors based on current scientific literature. CONCLUSIONS In addition to obvious physical factors (e.g. dose, dose rate, radiation quality, irradiation volume), potential factors modifying individual responses for radiation cataracts include sex, age and genetics, with comorbidity and coexposures also having important roles. There are indications and preliminary data identifying such potential modifiers of radiation cataract incidence or risk, although no firm conclusions can yet be drawn. Further studies and a consensus on the evidence are needed to gain deeper insights into factors determining individual responses regarding radiation cataracts and the implications for radiation protection.
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Affiliation(s)
- Stephen G R Barnard
- UK Health Security Agency (UKHSA), Radiation, Chemical and Environmental Hazards Division (RCEHD), Didcot, UK
| | - Nobuyuki Hamada
- Biology and Environmental Chemistry Division, Sustainable System Research Laboratory, Central Research Institute of Electric Power Industry (CRIEPI), Tokyo, Japan
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Quinlan RA, Clark JI. Insights into the biochemical and biophysical mechanisms mediating the longevity of the transparent optics of the eye lens. J Biol Chem 2022; 298:102537. [PMID: 36174677 PMCID: PMC9638808 DOI: 10.1016/j.jbc.2022.102537] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 11/18/2022] Open
Abstract
In the human eye, a transparent cornea and lens combine to form the "refracton" to focus images on the retina. This requires the refracton to have a high refractive index "n," mediated largely by extracellular collagen fibrils in the corneal stroma and the highly concentrated crystallin proteins in the cytoplasm of the lens fiber cells. Transparency is a result of short-range order in the spatial arrangement of corneal collagen fibrils and lens crystallins, generated in part by post-translational modifications (PTMs). However, while corneal collagen is remodeled continuously and replaced, lens crystallins are very long-lived and are not replaced and so accumulate PTMs over a lifetime. Eventually, a tipping point is reached when protein aggregation results in increased light scatter, inevitably leading to the iconic protein condensation-based disease, age-related cataract (ARC). Cataracts account for 50% of vision impairment worldwide, affecting far more people than other well-known protein aggregation-based diseases. However, because accumulation of crystallin PTMs begins before birth and long before ARC presents, we postulate that the lens protein PTMs contribute to a "cataractogenic load" that not only increases with age but also has protective effects on optical function by stabilizing lens crystallins until a tipping point is reached. In this review, we highlight decades of experimental findings that support the potential for PTMs to be protective during normal development. We hypothesize that ARC is preventable by protecting the biochemical and biophysical properties of lens proteins needed to maintain transparency, refraction, and optical function.
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Affiliation(s)
- Roy A Quinlan
- Department of Biosciences, Durham University, South Road Science Site, Durham, United Kingdom; Department of Biological Structure, University of Washington, Seattle, Washington, USA.
| | - John I Clark
- Department of Biological Structure, University of Washington, Seattle, Washington, USA.
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10
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Richardson RB. The role of oxygen and the Goldilocks range in the development of cataracts induced by space radiation in US astronauts. Exp Eye Res 2022; 223:109192. [DOI: 10.1016/j.exer.2022.109192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/26/2022] [Accepted: 07/13/2022] [Indexed: 11/04/2022]
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