• Journal of Radiation Industry
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• v.6 no.3
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• pp.217-221
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• 2012

The purpose of this study is to reduce the immune toxicity of lipopolysaccharide (LPS) by gamma irradiation. LPS was gamma-irradiated at the various doses of 20, 100 and 200 kGy and then evaluated on the immune toxicity through the cell proliferation, nitricoxide production and cytokine release. Cell proliferation significantly decreased in the intact LPS treated groups, whereas gamma-irradiated LPS treated group were not reduced the cell proliferation. Similarly, the production of nitric oxide and cytokine showed the high levels in the intact LPS treated group. However, gamma-irradiated LPS treated group remarkably decreased the production of nitric oxide and cytokine in dose-dependent manner. Therefore, gamma irradiation may effective method to reduce the immune toxicity of LPS.

• Radiation Oncology Journal
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• v.4 no.1
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• pp.1-13
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• 1986

In order to clarify the effect of radiation on the mouse jejunal crypt cells by combined administration of administration and radiation and also to evaluate the enhancing effect of adriamycin, the authors performed this study by delivering single irradiation of 1,000 to 1,600 rad to the whole abdomen of mice by cobalt-60 teletherapy unit. In combination with adriyamycin treatment groups, the drug was administered as single dose of 10 mg/kg either 2 hours before or 4 hours after graded single dose,900 to 1,400 rad, of irradiation. The authors studied the quantitative changes of intestinal crypt cells by microcolony survival assay technique and the morphological changes of small intestinal villi by scanning electron microscope in mice following to combined therapy with adriamycin and irradiation, The average number of jejunal crypts per circumference was $130{\pm}16$ in control group. The mean lethal dose(Do) of each irradiation alone and combined therapy groups 2 hours before and 4 hours after irradiation, were 160, 170, and 170 rad in cell survival curves, respectively. The dose effect factor(DEF) of adriamycin in each groups of pre-irradiation and post-irradiation were 1.19 and 1.26, respectively. The conical shaped villi were noted on 1,200 rad in irradiation alone group and 1,000 rad in combined groups. For the proper clinical application we must be careful of the radiation injury to small bowel when the anticancer chemotherapy and radiation therapy to the abdomen and pelvic area are used as combined therapeutic modality.

• Food Science and Preservation
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• v.14 no.3
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• pp.239-246
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• 2007

The effects of gamma irradiation on the physiochemical and physical characteristics of apples were investigated during post-irradiation storage at $4^{\circ}C\;and\;25^{\circ}C$. The contents of total and reducing sugars were analyzed and the results indicated that apples receiving 1 kGy of gamma irradiation did not show significant differences in sugar contents compared to non-irradiated controls. Important physiological characteristics were evaluated by measurement of total phenolic content and total flavonoid content, reducing power, and radical scavenging ability, and the results indicated that gamma irradiation at a dose of 1 kGy did not affect physiological activities. Changes in physical parameters such as weight loss, strength, cohesiveness and hardness, during post-irradiation storage, were temperature-dependent, whether the apples were irradiated or not The color and sensory acceptance of the apples were not affected by irradiation during cold storage. However, minor deterioration in color quality and sensory acceptance of irradiated apples was noted under ambient temperature storage. We conclude that gamma irradiation(1 kGy) does not affect apple nutritional content stability, functional properties, or physical characteristics, especially upon cold storage after radiation treatment.

• Journal of Radiation Industry
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• v.5 no.2
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• pp.159-164
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• 2011

A variety of natural polymers have been used as tissue engineering scaffolds, drug delivery system, and cosmetic materials due to their higher biocompatibility and water uptake. As a major component of extracellular matrix, hyaluronic acid consisting of D-glucuronic acid and N-acetylglucosamine has been popularly used as a hydrogel material. Even though it has good properties to be used in the tissue engineering and cosmetic industry, its higher viscosity has limited a potential use in a variety of applications; only low content should be applied in preparing above products. In the present study, we investigated the effect of electron beam irradiation on the properties of hyaluronic acid. Hyaluronic acid paste containing low contents of water changed to solution after electron beam irradiation ranging from 1 to 10 kGy, which didn't exhibit any alteration of surface properties and morphological change after freeze-drying. However, its viscosity was significantly decreased as absorbed dose increased, which was approximately one by hundred in comparison with the viscosity of original hyaluronic acid solution with same concentration. In addition, it can still interact with positive charged chitosan generating polyelectrolyte complex. Therefore, only viscosity was decreased after electron beam irradiation, whereas other properties of hyaluronic acid maintained. Consequently, these hyaluronic acids with lower viscosities can be used in a variety of applications in tissue engineering, drug delivery, and cosmetic industry.

• BMB Reports
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• v.34 no.2
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• pp.123-129
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• 2001

Cellular response to ionizing radiation is affected by cell types, radiation doses, and post-irradiation time. Based on the trypan blue dye exclusion assay in normal oral mucosal cells (OM cells), a 48 h post-irradiation was sufffcient and an adequate time point for the evaluation of radiation sensitivity Its $LD_{50}$ was approximately 1.83 Gy To investigate possible biomarkers useful for the biological radiodosimetry of normal epithelial cells (p53, c-fos, cyclin D1, cdc-2, pRb) EGF receptor phosphorylation and Erk activation were evaluated at different radiation doses and different post-irradiation times. From 0.5 Gy, p53 was accumulated in the nucleus of basal cells of the OM raft culture at 4 h post-irradiation and sustained up to 24 h post-irradiation, which suggests that radiation-induced apoptosis or damage repair was not yet completed. The number of p53 positive cells and biosynthesis of p53 were correlated with radiation doses. Both cyclin D1 and c-fos were only transiently induced within 1 h post-irradiation. Cyclin D1 was induced at all radiation doses. However, cfos induction was highest at 0.1 Gy, approximately 7.3 fold more induction than the control, whose induction was reduced in a reverse correlation with radiation dose. The phosphorylation pattern of cdc-2 and pRb were unaffected by radiation. In contrast to A431 tails overexpressing the EGF receptor approximately 8.5 fold higher than normal epithelial, the OM cells reduced the basal level of the EGF receptor phosphorylation in a radiation dose dependent fashion. In conclusion, among radiation-induced biomolecules, the p53 nuclear accumulation may be considered for the future development of a useful marker far biological radiodosimetry in normal epithelial tissue since it was sustained for a longer period and showed a dose response relationship. Specific c-fos induction at a low dose may also be an important finding in this study It needs to be studied further for the elucidation of its possible connection with the low dose radio-adaptive response.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1612-1616
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• 2007

Physiological activities of the 70% ethanol extract from boiled-water of Enteroctopus dofleini (BE) upon a gamma irradiation were determined to examine the possible use of the food processing by-product as a functional material for food or cosmetic composition. Electron donating ability and the content of total phenolic compounds increased from 65% to 72% and from 406 ppm to 476 ppm, respectively, by 10 kGy gamma irradiation. A Salmonella mutagenicity assay indicated that the gamma-irradiated BE did not show any mutagenicity. Tyrosinase inhibition activity of the irradiated BE also increased from 57% to 86% with irradiation doses. These results show that irradiation can be used to increase the physiological activities of BE for its potential use as food or cosmetic materials.

• Journal of Radiation Industry
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• v.4 no.3
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• pp.227-231
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• 2010

The purpose of this study was to investigate the expression mechanism of MCP-1 in gamma-irradiated RAW 264.7 macrophage cells. MCP-1 plays an important role in attracting monocyte to injured site at the early inflammation stage. However the production mechanism of MCP-1 by gamma-irradiation in RAW 264.7 macrophage cells was almost undiscovered. We found that MCP-1 was produced in RAW 264.7 macrophage cells by irradiation with 5 Gy. And these inceases were attenuated by specific inhibitors treatment, such as $NF-{\kappa}B$, JNK, ERK, JAK2, and Pyk2. These results indicate that radiation-induced MCP-1 production is mediated by MyD88- and TRIF-dependent pathways in RAW 264.7 macrophage cells. Furthermore, gamma-irradiation induced heme oxygenase-1 (HO-1) expression in RAW 264.7 macrophage cells. However this induction level was reduced before MCP-1 and $IFN-{\beta}$ production.

• Journal of Radiation Protection and Research
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• v.33 no.3
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• pp.93-97
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• 2008

The purpose of this study reported here was to investigate the ability of Bu-Zhong-Yi-Qi-Tang (BZYQT), known to elevate hematopoietic functions, to protect mice undergoing treatment with whole body single gamma-irradiation. BZYQT was given (25 mg/kg B.W.) intraperitoneally at 36 and 12 hours before irradiation and 30 minute and 24 hours after irradiation. Recovery of neutrophil and lymphocyte counts was significantly stimulated by extract of BZYQT. Stimulated recovery by the extract from the BZYQT was also observed in thrombocyte. However, the anti-radiation effect of erythrocyte, hemoglobin and hematocrit was not as significant as that of leukocyte. Further studies are needed to better characterize the protective nature of BZYQT extract and its ingredients.

• The Journal of Korean Society for Radiation Therapy
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• v.2 no.1
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• pp.75-80
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• 1987

Intraoperative Radiation therapy (IORT) is a cancer treatment modality in which resectable masses or organs are removed surgically and residual cancer calls are sterilized by irradiation with a single massive dose during while patient is still anesthetized. Because it is possible that the turner mass can be visualized directly at the time of surgical exploration, tumor volume can be determined more precisely and at the same tin e sensitive adjacent structures can be pulled aside from the irradiation. With these theoretical advantages as compare to conventional external irradiation, IORT can improve the therapeutic ratio of tumor control to normal tissue injury. Yonsei cancer center initiated a pilot study of multidisciplinary IORT program in february of 1986 for the fist attempt in Korea. IORT Was performed in 7 patients with stomach cancer by using existing NELAC-1018 Linear Accelerator treatment room as a surgical suite. IOTR team included department of surgery, Department of Anethesiology, Department of Clinical pathology, operating room nursing personal and Department of radiation oncology.

• Journal of Radiation Industry
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• v.6 no.3
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• pp.211-215
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• 2012

In this study, crosslinked polyethylene (PE) foam sheets were prepared through gamma-ray irradiation. PE foam sheets were prepared through a foaming process using sodium bicarbonate as a blowing and foaming agent. The prepared PE foam sheets were then crosslinked through gamma-ray irradiation. The crosslinking degree was increased to 86.0% with an increase in the absorption dose. The tensile strength of the crosslinked PE foam sheets was increased with an increase in the absorption dose. However, the elongation-at-break of the crosslinked PE foam sheets was decreased. The thermal decomposition temperature of the crosslinked PE foam sheets was increased to $421.2^{\circ}C$ with an increase in the absorption dose. The SEM analysis revealed that the morphology was not changed significantly after the crosslinking through gamma-ray irradiation.