• Asian Pacific Journal of Cancer Prevention
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• 제16권7호
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• pp.2613-2617
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• 2015

Radiation induced lung injury has long been considered a treatment limiting factor for patients requiring thoracic radiation. This radiation induced lung injury happens early as well as late. Radiation induced lung injury can occur in two phases viz. early (< 6 months) when it is called radiation pneumonitis and late (>6 months) when it is called radiation induced lung fibrosis. There are multiple factors that can be patient, disease or treatment related that predict the incidence and severity of radiation pneumonitis. Radiation induced damage to the type I pneumocytes is the triggering factor to initiate such reactions. Over the years, radiation therapy has witnessed a paradigm shift in radiation planning and delivery and successfully reduced the incidence of lung injury. Radiation pneumonitis is usually a diagnosis of exclusion. Steroids, ACE inhibitors and pentoxyphylline constitute the cornerstone of therapy. Radiation induced lung fibrosis is another challenging aspect. The pathophysiology of radiation fibrosis includes continuing inflammation and microvascular changes due to pro-angiogenic and profibrogenic stimuli resembling those in adult bronchiectasis. General supportive management, mobilization of airway secretions, anti-inflammatory therapy and management of acute exacerbations remains the treatment option. Radiation induced lung injury is an inevitable accompaniment of thoracic radiation.

• Nuclear Engineering and Technology
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• 제45권3호
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• pp.385-392
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• 2013

Zirconium and zirconium alloys are widely used as nuclear reactor core materials such as fuel cladding and guide tubes because they have excellent corrosion- and radiation-resistant properties. In the reactor core, zirconium alloys are subjected to high-energy neutron fluence, causing radiation-induced dislocation and growth. To discern a possible correlation between radiation-induced dislocation and growth, characteristics of dislocation and growth in zirconium and its alloys are examined. The radiation-induced dislocation including and dislocation loops is reviewed in various temperature and fluence ranges, and their growth behavior is examined in the same way. To further a fundamental understanding, radiation-induced growth prediction models are briefly reviewed. This research will assist in the design of zirconium based components as well as the safety analysis of various reactor conditions, in both research and commercial reactors.

• Radiation Oncology Journal
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• 제33권2호
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• pp.66-74
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• 2015

Trace elements play crucial role in the maintenance of genome stability in the cells. Many endogenous defense enzymes are containing trace elements such as superoxide dismutase and metalloproteins. These enzymes are contributing in the detoxification of reactive oxidative species (ROS) induced by ionizing radiation in the cells. Zinc, copper, manganese, and selenium are main trace elements that have protective roles against radiation-induced DNA damages. Trace elements in the free salt forms have protective effect against cell toxicity induced by oxidative stress, metal-complex are more active in the attenuation of ROS particularly through superoxide dismutase mimetic activity. Manganese-complexes in protection of normal cell against radiation without any protective effect on cancer cells are more interesting compounds in this topic. The aim of this paper to review the role of trace elements in protection cells against genotoxicity and side effects induced by ionizing radiation.

• Journal of Radiation Protection and Research
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• 제21권3호
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• pp.175-182
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• 1996

BEIR V 방법을 사용하여 한국인이 단일 및 연속 방사선피폭을 받았을 경우 일생동안 방사선에 의한 암사망을 평가하였다. 단일피폭시 지배적으로 나타나는 암은 젊은층 피폭의 경우는 소화기암, 노령층피폭의 경우는 호흡기 암이었다. 한국인 모든 집단이 피폭받았을 경우, 지배적으로 나타나는 암은 소화기 암이었다. 출생에서 사망까지 1mGy/yr의 피폭을 연속적으로 받았을 경우, 방사선에 의한 모든 암의 발생은 자연 암발생의 3% 정도였다.

• 동의생리병리학회지
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• 제18권5호
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• pp.1301-1308
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• 2004

The purpose of this study was to observe the effects of far-infrared on rheumatoid arthritis induced rats by type ⅡI collagen with the change of arthritis index, hind paw volume, TNF-α and histopathologic findings. Thirty-six Sprauge-Dawley rats which were divided into four group. Group Ⅰ : Normal group, Group Ⅱ : Collagen-Induced Arthritis group, Group Ⅲ : Far-Infrared 25㎝ radiation group, Group Ⅳ : Far-Infrared 35㎝ radiation group. The results of this study were as follows: In arthritis index, far-infrared radiation group(Ⅲ, Ⅳ) are more decreased than collagen-induced arthritis group(Ⅱ). Group Ⅲ and Ⅳ showed the most significant effect at 14 day(p<0.05). In hind paw, far-infrared 25㎝ radiation group(Ⅲ) significantly decreased more than only collagen-induced arthritis group on day 14(p<0.05). Far-infrared 35㎝ radiation group(Ⅳ) significantly decreased more than collagen-induced arthritis group on day 3, 7 and 14(p<0.05). In the ELISA study of TNF-α concentration, collagen-induced arthritis group significantly increased in the concentration more than normal group. Far-infrared radiation group(Ⅲ, Ⅳ) decreased in TNF-α concentration more than collagen-induced arthritis group(Ⅱ) on day 14. In histopathologic findings, collagen-induced arthritis(Ⅱ) and far-infrared 25㎝ radiation group(Ⅲ) increased in synovial membrane thickness on 3 day. Far-infrared 35 em radiation group(Ⅳ) decreased in the concentration more than collagen-induced arthritis group on day 14. The above results suggest that far-infrared radiation effectively reduced in rheumatoid arthritis. It would be considered that far-infrared has an effects on relieving rheumatoid arthritis.

• 방사선산업학회지
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• 제4권1호
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• pp.91-94
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• 2010

A number of epidemiological studies as well as biological experiments, showed that genistein, one of the isoflavone, prevents prostate cancer occurrence. In this study, we showed that genistein inhibited the cell proliferation of human promyeoltic leukemia HL-60 cells and induced G2/M phase arrest. In addition, combination of genistein treatment and ${\gamma}$-irradiation displayed synergistic effect in apoptotic cell death of HL-60 cells. This means that the repair of genistein-induced DNA damage was hindered by ${\gamma}$-radiation and thus cell death was increased. In conclusion, genistein is one of the important chemicals that sensitize radiation-induced cell death.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6441-6446
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• 2012

Background: Radiation therapy plays an important role in lung carcinoma treatment. However, the incidence of symptomatic radiation-induced lung injury is high. This study aimed to evaluate radioprotective effects of flavonoids extracted from Astragalus complanatus and mechanisms of action against radiation damage. Methods: Alteration in antioxidant status and levles of several cytokines were investigated in BABL/C mice treated with 4 mg/kg b.wt. flavonoids after exposure to 10Gy thoracic radiation. Results: Serum levels of SOD in the flavonoids+radiation group were significantly higher compared to the radiation control group, while TGF-${\beta}1$ and IL-6 were lower. Mice in the radiation control group displayed more severe lung damage compared with the flavonoids+radiation group. The expression of TGF-${\beta}1$ and TNF-${\alpha}$ in the radiation control group was markedly increased in alveolar epithelial cells and macrophages of the alveolar septum. Conclusions: From the results of the present study, flavonoids could be excellent candidates as protective agents against radiation-induced lung injury.

• Radiation Oncology Journal
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• 제32권3호
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• pp.103-115
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• 2014

To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제46권4호
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• pp.288-291
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• 2020

Angiosarcoma is a rare malignant mesenchymal tumor of vascular or lymphatic origin and represents less than 1% of all malignant tumors. Radiation therapy is a standard treatment in many head and neck cancer cases, but ionizing radiation is associated with radiation carcinogenesis including radiation-induced angiosarcoma. In this article, we report a rare case of radiation-induced angiosarcoma found in a 58-year-old female patient who was previously diagnosed with an odontogenic keratocyst and mucoepidermoid carcinoma.

• Nuclear Engineering and Technology
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• 제50권3호
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• pp.526-530
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• 2018

Human fingernails were used to estimate the radiation dose via electron paramagnetic resonance measurements of radiation-induced radicals. The limiting factors in this research were mechanically induced electron paramagnetic resonance signals due to the mechanical stress during the preparation of the samples. Therefore, different treatment methods of fingernails were used to reduce the mechanically induced signals. The results demonstrate that the mechanically induced and radiation-induced signals have apparently different microwave power saturation behaviors. In addition, the mechanically induced signal shows a fading evolution over time and reaches a constant value. Chemical treatment using the different reagents showed that the minimum mechanically induced signal was obtained using the dithiothreitol reagent. The dose-response curves of the samples treated with dithiothreitol for 30 minutes demonstrated a greater linearity than those of samples treated for 5 minutes. Therefore, to find an unknown absorbed dose in a fingernail sample using a calibration curve, we recommend adopting the mentioned chemical treatment procedure to reduce the uncertainty.