• 대한방사선기술학회지:방사선기술과학
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• 제3권1호
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• pp.95-105
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• 1980

흰불나방(Hyphantria cunea Drury)의 각(各) 변태단계(變態段階)에 따라 $1.75{\sim}7krad$의 Cobalt-60 $\gamma$선(線)을 전신조사(全身照射)하여 $\gamma$선조사(線照射)에 의(依)한 중장세포(中腸細胞)의 조직학적(組織學的) 변화(變化)를 광학현미경(光學顯微鏡)으로 정상군(正常群)과 비교(比較) 관찰(觀察)하였던 바, 다음과 같은 결과(結果)를 얻었다. 1. 중장(中腸)의 상피세포(上皮細胞)는 원주세포(圓柱細胞), 배상세포(杯狀細胞), 신생세포(新生細胞)로 구성(構成)되어 있었다. 2. 조사(照射)의 영향(影響)은 조사(照射)된 선량(線量)과 변태시기(變態時期)에 따라 변화(變化)되었다. 3. 조직학적(組織學的) 변화(變化)의 정도(程度)는 조사선량(照射線量)이 많을수록 증대(增大)되었다. 4. 방사선(放射線)의 감수성(感受性)은 종령유충(終齡幼蟲), 용8일(日)에서 가장 높았다.

• 한국의학물리학회지:의학물리
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• 제34권4호
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• pp.41-47
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• 2023

Purpose: This study aimed to dosimetrically compare the technique of three-dimensional conformal radiotherapy (3D CRT), which is a traditional prophylactic cranial irradiation method, and the intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques used in the last few decades with the dynamic conformal arc therapy (DCAT) technique. Methods: The 3D CRT, VMAT, IMRT, and DCAT plans were prepared with 25 Gy in 10 fractions in a Monaco planning system. The target volume and the critical organ doses were compared. A comparison of the body V₂, V₅, and V₁₀ doses, monitor unit (MU), and beam on-time values was also performed. Results: In planned target volume of the brain (PTV_Brain), the highest D99 dose value (P<0.001) and the most homogeneous (P=0.049) dose distribution according to the heterogeneity index were obtained using the VMAT technique. In contrast, the lowest values were obtained using the 3D CRT technique in the body V₂, V₅, and V₁₀ doses. The MU values were the lowest when DCAT (P=0.001) was used. These values were 0.34% (P=0.256) lower with the 3D CRT technique, 66% (P=0.001) lower with IMRT, and 72% (P=0.001) lower with VMAT. The beam on-time values were the lowest with the 3D CRT planning (P<0.001), 3.8% (P=0.008) lower than DCAT, 65% (P=0.001) lower than VMAT planning, and 76% (P=0.001) lower than IMRT planning. Conclusions: Without sacrificing the homogeneous dose distribution and the critical organ doses in IMRTs, three to four times less treatment time, less low-dose volume, less leakage radiation, and less radiation scattering could be achieved when the DCAT technique is used similar to conventional methods. In short, DCAT, which is applicable in small target volumes, can also be successfully planned in large target volumes, such as the whole-brain.

• 대한방사선기술학회지:방사선기술과학
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• 제23권1호
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• pp.81-89
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• 2000

In the present study, to determine whether the ascorbate protect against radiation damage and the possible relationship among the radioprotective effects and antioxidant actions, the effects of ascorbate(240 mg/kg, i.p) pretreatment of mice on the survival ratio, splenic weight, major antioxidant enzymes(SOD, catalase and glutathione peroxidase) activities, glutathione contents and lipid peroxidation in the liver were examined for 2 weeks after whole-body ${\gamma}-irradiation$(6.5 Gy). The 30-day survival ratio Increased from 10% to 47% for mice treated with ascorbate. The ascorbate decreased the extent of loss in splenic weight and stimulated recovery of splenic weight in irradiated mice(p<0.01). On the day of 14 after ${\gamma-irradiation}$, the ascorbate pretreatment produced a slight increase of antioxidant enzymes activities and significantly increased reduced glutathione(GSH) contents(P<0.05) in the liver compared with non-treated group. Pretreatment with the ascorbate significantly decreased GSSG/total GSH ratio(p<0.05) without the change of GSSG in the liver and inhibited the radiation-induced increase in the hepatic malondialdehyde levels(p<0.05). In these results, we found that its radioprotective effect by protecting antioxidant enzyme activities and glutathione contents from radiation induced a decrease, and thereby suppressing lipid peroxidation which is induced by free radicals.

• Archives of Pharmacal Research
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• 제28권3호
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• pp.343-350
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• 2005

Gamma radiation causes suppression of the immune function, and immune properties are related to cytokine production. In the present study, the polysaccharide, Ginsan, purified from an ethanol-insoluble fraction of Ginseng (Panax ginseng C.A. Meyer, Araliaceae) water extract was studied to assess its effects on the immunosuppressive activities of gamma radiation. Gin­san was found to stimulate murine normal splenocytes by inducing the mRNA expressions of Th1 and Th2 type cytokines, and also restore the mRNA expression of IFN-$/gamma$, Th1 cytokine, after its inhibition by whole-body gamma irradiation. Therefore, Ginsan was found to restore the T lymphocytes function that had been suppressed by gamma irradiation in allogenic MLR (mixed lymphocyte reactions). However, Ginsan exhibited no excessive stimulatory effects on the control group. The above results indicated that Ginsan may constitute a new noble agent for the improvement of gamma radiation-induced immunosuppression.

• Journal of Ginseng Research
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• 제22권1호
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• pp.1-10
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• 1998

In the present study, to determine whether the antioxidative components of Korean red ginseng protect against radiation damage and the possible relationship among the radioprotective effects and antioxidant actions, the effects of total saponin (200 mg/kg, ip) and lipophilic fraction (200 mg/kg, oral) preferment of mice on the survival ratio, major antioxidant enzymes (SOD, catalase and glutathione peroxidase) activities, glutathione levels and lipid peroxidation in the liver were exiled for 2 weeks after whole ${\gamma}$-body ${\gamma}$-irradiation (6.5 Gy). The 30-day survival ratio increased from 10% to 57% and 40% for mice treated with total saponin and lipophilic fraction, respectively. On day 14 after ${\gamma}$-irradiation, the ginseng total saponin pretreatment produced a slight increase of antioxidant enzymes activities and significantly Increased reduced glutathione (GSH) contents (p<0.05) in the liver compared with non-treated group. Pretreatment with ginseng total saponin significantly deceased GSSG/total GSH ratio (p<0.05) without change of GSSG in the liver and inhibited the radiation-induced incense in the hepatic malondialdehyde levels. (p<0.05) In these results, GSH plays an important role in the liver in several detoxifications and the reduction of lipid peroxides. Thus, it appears that total saponin of red ginseng exerts its radioprotective effect by accelerating the production of endogenous antioxidants, such as glutathione from radiation induced damages and thereby oxygen free radicals.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2405-2425
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• 2014

Radiation exposure leads to several pathophysiological conditions, including oxidative damage, inflammation and fibrosis, thereby affecting the survival of organisms. This review explores the radiation countermeasure properties of fourteen (14) plant extracts or plant-derived compounds against these cellular manifestations. It was aimed at evaluating the possible role of plants or its constituents in radiation countermeasure strategy. All the 14 plant extracts or compounds derived from it and considered in this review have shown some radioprotection in different in vivo, ex-vivo and or in vitro models of radiological injury. However, few have demonstrated advantages over the others. C. majus possessing antioxidant, anti-inflammatory and immunomodulatory effects appears to be promising in radioprotection. Its crude extracts as well as various alkaloids and flavonoids derived from it, have shown to enhance survival rate in irradiated mice. Similarly, curcumin with its antioxidant and the ability to ameliorate late effect of radiation exposure, combined with improvement in survival in experimental animal following irradiation, makes it another probable candidate against radiological injury. Furthermore, the extracts of P. hexandrum and P. kurroa in combine treatment regime, M. piperita, E. officinalis, A. sinensis, nutmeg, genistein and ginsan warrants further studies on their radioprotective potentials. However, one that has received a lot of attention is the dietary flaxseed. The scavenging ability against radiation-induced free radicals, prevention of radiation-induced lipid peroxidation, reduction in radiation cachexia, level of inflammatory cytokines and fibrosis, are some of the remarkable characteristics of flaxseed in animal models of radiation injury. While countering the harmful effects of radiation exposure, it has shown its ability to enhance survival rate in experimental animals. Further, flaxseed has been tested and found to be equally effective when administered before or after irradiation, and against low doses (${\leq}5Gy$) to the whole body or high doses (12-13.5 Gy) to the whole thorax. This is particularly relevant since apart from the possibility of using it in pre-conditioning regime in radiotherapy, it could also be used during nuclear plant leakage/accidents and radiological terrorism, which are not pre-determined scenarios. However, considering the infancy of the field of plant-based radioprotectors, all the above-mentioned plant extracts/plant-derived compounds deserves further stringent study in different models of radiation injury.

• 한국식품과학회지
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• 제47권3호
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• pp.388-393
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• 2015

본 연구는 BALB/c 마우스에서 감마선 조사 후 루틴을 7일 동안 경구투여하여 감마선 조사로 인한 조혈계 및 간세포 손상에 대한 방사선 회복 효과를 검토하였다. 루틴의 투여는 감마선 조사군에 비해 조혈 면역계 손상을 억제하여 보호하였으며, 증가된 간독성 지표 효소도 유의적으로 감소하여 간세포 손상에 대한 보호효과를 확인하였다. 방사선 조사에 의해 체내에서 생성된 자유 라디칼은 생체물질과 결합하여 지질과산화를 일으키고 산화적 스트레스를 유도하여 조직을 손상시킨다. 루틴을 투여한 군은 감마선 조사군에 비해 지질과산화가 유의적으로 낮게 나타나 방사선에 의한 장해를 감소시킨 것으로 사료된다. 루틴을 투여한 군의 항산화 효소의 활성은 감마선 조사군에 비해 유의적으로 증가하여 생체 내에 항산화 활성을 회복시켰다. 이 상의 결과를 통해 방사선 조사 후에 루틴의 투여는 방사선에 의한 조혈계 및 간세포 손상에 대해 회복 효과가 있어 방사선 보호제로 유용하게 사용될 수 있다.

• Journal of Radiation Protection and Research
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• 제29권4호
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• pp.237-242
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• 2004

방사선피폭 후 급성조혈계 손상에 대한 Melatonin과 Ge-132의 방어효과를 8 Gy의 선량으로 급성, 전신피폭 된 마우스에서 연구하였다. Melatonin은 피폭 1시간 전에 200 mg/kg의 용량으로 복강 내 주사하였고, Ge-132는 130 - 150 mg/kg/d의 용량으로 피폭 후 5일째부터 20일째까지 경구복용 시켰다. 방사선방어 효과를 평가하기 위해 비장에서 TUNEL assay를 실시하였고 혈액 내 림프구와 총 백혈구 수치를 측정하였다. 피폭 후 30일째까지의 생존분석을 위해 4 실험군들 (피폭단독군, melatonin 전처치군, Ge-132 후처치군, melatonin 전처치 및 Ge-132 후처치군)에서 날짜경과에 따른 사망을 측정하였다. 피폭단독군과 melatonin 전처치군 간에 세포고사지수 (47.8% vs 45.9%, p=0.385)와 림프구 수치 ($97/{\mu}{\ell}\;vs\;101/{\mu}{\ell}$, p=0.898)에서 차이가 없었으나, 총 백혈구 수치는 melatonin 전처치군에서 유의하게 높은 수치 ($147/{\mu}{\ell}\;vs\;306/{\mu}{\ell}$, p=0.010)를 보였다. 피폭 후 30일째의 생존율은 피폭단독군, melatonin 전처치군, Ge-132 후처치군, 그리고 melatonin 전처치 및 Ge-132 후처치군에서 각각 21.4%, 100%, 35.7%, 그리고 85.7%였다. 실험군들 간의 생존분석에서 melatonin 전처치 군은 피폭단독군(p=0.000)이나 Ge-132 후처치군(p=0.0003)에 유의하게 높은 생존을 보였다. 본 연구결과는 방사선피폭 후 급성조혈계증후군에 대하여 melatonin이 방사선방어제로서 효능을 지님을 보여주고 있다.

• 한국식품과학회지
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• 제32권5호
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• pp.1128-1134
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• 2000

본 연구는 해풍에서 반건조된 꽁치(Cololabis seira)로 만든 과메기에 대한 감마선 조사에 의한 품질 특성을 평가하기 위해 수행되었다. 과메기의 가식부위를 준비하여, 진공포장하고, 3과 5 kGy에서 각각 감마선을 조사한 후 $5^{\circ}C$에 저장하였다. VBN및 TMA 함량은 조사직후 차이는 없었고, 저장 중 감마선 조사선량이 증가할수록 함량의 증가가 억제되는 것으로 나타났다. 조사직후 TBA는 모든 처리구에서 차이가 없었고 저장 중 증가하였으나, 감마선 조사에 의한 영향은 없었다. 휘발성 향기성분은 감마선 조사에 의해 전체적인 함량이 줄어들었다. 과메기의 물성은 감마선 조사구의 경우 저장 60일째에도 물성을 그대로 유지하였으나, 비조사구는 저장 중 연화되는 것으로 나타났다. 관능평가결과 조사직 후 감마선 조사구와 비조사구의 차이가 없었고, 감마선 조사구가 저장 60일째까지 관능적으로 품질이 유지되는 것으로 나타났다. 따라서 과메기에 대한 감마선 조사는 과메기의 품질을 유지시키는 효과적인 방법이라 할 수 있다.

• 대한수의학회지
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• 제48권4호
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• pp.393-399
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• 2008

We investigated the potential of fucoidan for its ability to provide protection from gamma rayinduced damage. In our results, the fucoidan significantly improved the counts of endogenous colony forming unit to $9.5 {\pm} 1.5$, from $5.5 {\pm} 2.5$ compared with un-treated irradiated control group at 10 day after 7 Gy whole body irradiation. After 2 Gy irradiation, fucoidan treatment attenuated the percent of tail DNA of splenocytes, parameters of DNA damage, from $30.17 {\pm} 1.7%$ to $13.67 {\pm} 2.81%$ 2.81% by comet assay and also accelerated the proliferation of splenocytes, compared with un-treated irradiated control group by 3Hthymidine incorporation assay. Furthermore, fucoidan decreased the number of apoptotic fragments per intestinal crypt by 31.8% at 1 days after 2 Gy irradiation. These results indicated that the fucoidan significantly improved the hematopoietic recovery, prevented the DNA damage in immune cells and enhanced their proliferation, which had been suppressed by ionizing radiation. in addition, fucoidan rescued intestinal cells from radiation-induced apoptosis. Thus, this study raises the possibility of using fucoidan as adjuvant therapeutic agent after radiotherapy.