• Food Science of Animal Resources
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• v.29 no.1
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• pp.34-39
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• 2009

The objective of this study was investigated to apply the fucoidan and laminarin extract from low-grade Undaria pinnatifida to real food product, a pork patty. Pork patties added with fucoidan and laminarin showed lower lipid oxidation and the inhibition against lipid oxidation was shown to be dependent on the irradiation doses. The Hunter color values of pork patty added with fucoidan increased significantly with an increase of irradiation dose. The hardness profiles of the patties with fucoidan and laminarin was decreased, but the amount of water in the patties was increased. Also, the combination of gamma irradiation and addition of fucoidan and laminarin was shown to be effective for the microbiological control. These results suggested that gamma irradiation and fucoidan and laminarin treatment showed the positive effect on microbial stability and quality of the pork patty.

• Archives of Pharmacal Research
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• v.18 no.6
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• pp.410-414
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• 1995

Adaptive response induced by low dese .gamma.-ray irradiation in human cervical carcinoma cells was examined. Cells were exposured to low dose of .gamma.-ray irradiation in human cervical carcinoma cells was examined. Cells were exposured to low dose of .gamma.-ray (1-cGy) followed by high doses of r-ray irradiation (0,1,2,3,5,7 and 9Gy for chlnogenic assay or 1.5Gy for micronucleus assay) with various time intervals. Survival fractions of cells in both low dose-irradiated and unirrated groups were analyzed by clonogenic assay. Surviva fractions of low dose-irradiated in cell survival was maximum when low and high dose irradiation time interval was 4 hr. Frequencies of micronuclei which is an indicative of chromosome aberration were also enutained from survival fractions analyzed by clonogenic assay, maximum when low and high dose irradiation time interval was 4hr. Frequencies of micronuclei which is an indicative of chromosome aberration were also enumerated in both low dose-irradiated and unirradiated groups. In consiststent with the result obtained from survival fractions analyzed by clonogenic assay, maximum reduction in frquencies of micronuclei was observed when low dose radiation was given 4 hr prior to high response to subsequent high dose .gamma.-ray irradiation in human cervical carcinomal cells. Our data suggest that one of the possible mechanisms of adaptive response induced by low dose rediation is the increase in repair of DNA double strand breaks in low dose radiation-adapted cells.

• Journal of Radiation Protection and Research
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• v.37 no.3
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• pp.123-128
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• 2012

Evidence suggests that even low-dose irradiation can lead to progressive cognitive decline and memory deficits, which implicates, in part, hippocampal dysfunction in both humans and experimental animals. This study examined whether diethyldithiocarbamate (DDC) could attenuate memory impairment, using passive avoidance and object recognition test, and suppression of hippocampal neurogenesis, using the TUNEL assay and immunohistochemical detection with markers of neurogenesis (Kiel 67 (Ki-67) and doublecortin (DCX)) in adult mice treated with gamma radiation (0.5 or 2 Gy). DDC was administered intraperitonially at a dosage of 1,000 $mg{\cdot}kg^{-1}$ of body weight at 30 min. before irradiation. In passive avoidance and object recognition memory test, the mice, trained for 1 day after acute irradiation (2 Gy) showed significant memory deficits compared with the sham controls. The number of TUNEL-positive apoptotic nuclei in the dentate gyrus (DG) was increased 12 h after irradiation. In addition, the number of Ki-67- and DCX-positive cells were significantly decreased. DDC treatment prior to irradiation attenuated the memory defect, and blocked the apoptotic death. DDC may attenuate memory defect in a relatively low-dose exposure of radiation in adult mice, possibly by inhibiting a detrimental effect of irradiation on hippocampal neurogenesis.

• Radiation Oncology Journal
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• v.12 no.3
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• pp.285-293
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• 1994

Purpose : The study was designed to investigate the effect of cis-dichlorodiammineplatinum(II)(cis-DDP) on the radiation-induced cardiomyopathy in the rat. Materials and Methods : The myocardial damage was assessed by histopathologic changes. In radiation alone group, radiation dose ranged from 10-40 Gy X-ray in a single dose and in combined group, cis-dichlorodiammineplatinum(II) at a dose of 6 mg/kg was given intraperitoneally immediately after irradiation of same dose with X-ray alone group. Results : The early changes by radiation included congestion, inflammatory cell infiltrations and fibrosis in myocardial interstitium with focal myocardial necrosis, which was noted in 10 Gy group, Myocardial fibrosis was increased by increasing dose of radiation but myocardial necrosis was not Proportional to radiation dose. cis-DDP alone group showed minimal degeneration of myocardium with surrounded by inflammatory cell infiltrations. In combined group, myocardial fibrosis in 10 Gy group were similar to radiation alone group, but 30 Gy and 40 Gy groups showed severer changes. Electron microscopic examination showed disruption of Z-band and edema of mitochondria with decreased matrix density in 20 Gy radiation group which were severer in 40 Gy radiation group. Combined group showed endothelial changes and disruption of Z-band worse than radiation alone group as well as increased connective tissue, which was considered as a hallmark of late change in radiation-induced heart disease. Conclusion : This results showed minimal enhancement of the radiation-induced cardiomyopathy in rats by cis-DDP.

• The Journal of Advanced Prosthodontics
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• v.8 no.5
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• pp.363-371
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• 2016

PURPOSE. On maxillofacial tumor patients, oral implant placement prior to postoperative radiotherapy can shorten the period of prosthetic reconstruction. There is still lack of research on effects of post-implant radiotherapy such as healing process or loading time, which is important for prosthodontic treatment planning. Therefore, this study evaluated the effects of post-implant local irradiation on the osseointegration of implants during different healing stages. MATERIALS AND METHODS. Custom-made implants were placed bilaterally on maxillary posterior edentulous area 4 weeks after extraction of the maxillary first molars in Forty-eight Sprague-Dawley rats. Experimental group (exp.) received radiation after implant surgery and the other group (control) didn't. Each group was divided into three sub-groups according to the healing time (2, 4, and 8 week) from implant placement. The exp. group 1, 2 received 15-Gy radiation 1 day after implant placement (immediate irradiation). The exp. group 3 received 15-Gy radiation 4 weeks after implant placement (delayed irradiation). RESULTS. The bone mineral density (BMD) was significantly lower in the immediate irradiation groups. BMD was similar in the delayed irradiation group and the control group. The irradiated groups exhibited a lower bone-to-implant contact ratio, although the difference was not statistically significant. The irradiated groups also exhibited a significantly lower bone volume and higher empty lacuna count than the control groups. No implant failure due to local irradiation was found in this study. CONCLUSION. Within the limits of this study, the timing of local irradiation critically influences the bone healing mechanism, which is related to loading time of prostheses.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.265-269
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• 2003

Gamma irradiation treatment was performed at the early and mid-fermentation stages of Kimchi preparation. Changes in fermentative microorganisms and lactate dehydrogenase activity during the fermentation periods were investigated to determine proper irradiation point for extending the shelf life of Kimchi. Initial levels of acid producing bacteria and yeast in Kimchi were 10$^4$ CFU g$^{-1}$ and 10$^1$ CFU g$^{-1}$ , and reached up to 10$^{9}$ CFU g$^{-1}$ after 15 days and 10$^{7}$ CFU g$^{-1}$ after fermentation for 30 days at 1$0^{\circ}C$, respectively. The radiation resistance of acid producing bacteria in the earlier stage (D$_{10}$ value was 0.87 kGy) was higher than at the midfermentation stage (after 10 days at 1$0^{\circ}C$, D$_{10}$ value was 0.69 kGy). Microbial growth and lactate dehydrogenase activity were inhibited significantly by gamma irradiation at the early fermentation stage of Kimchi and acidification was effectively delayed during the subsequent storage period. Although the growth of fermentative microorganisms was inhibited by gamma irradiation at the mid-fermentation stage of Kimchi, lactate dehydrogenase activity was maintained and acidification continued during the storage period.

• Korean Journal of Veterinary Research
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• v.42 no.4
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• pp.475-483
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• 2002

We performed this study to determine the effect of Korean favorite teas (green tea, ginseng tea, coffee and barley tea) on jejunal crypt survival, endogenous spleen colony formation and apoptosis in jejunal crypt cells of mice irradiated with high and low dose of ${\gamma}$-radiation. Jejunal crypts were protected by pretreatment of green tea (P.O.: 1.25% water extract, for 7 days before irradiation., I.P.: 50 mg/kg of body weight, at 12 and 36 hours before irradiation, p<0.01) or ginseng (I.P.: 50 mg/kg of body weight, at 12 and 36 hours before irradiation, p<0.05). Green tea (p<0.05) or ginseng (p<0.05) administration before irradiation (I.P. at 12 and 36 hours before irradiation) resulted in an increase of t formation of endogenous spleen colony. The frequency of radiation-induced apoptosis was also reduced by pretreatment of green tea (P.O.: p<0.005, I.P.: p<0.05), pretreatment of ginseng (P.O.: p<0.005, I.P.: p<0.005) or posttreatment of ginseng (I.P.: 50 mg/kg of body weight, at 30 minutes after irradiation, p<0.05). Treatment with coffee or barley tea showed no significant modifying effects on the radiation-induced damages. These results indicated that green tea and ginseng might be a useful radioprotector, especially since it is a relatively nontoxic natural product. Further studies are needed to characterize better the promotion nature of green tea, ginseng and its components.

• Korean Journal of Veterinary Research
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• v.51 no.3
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• pp.177-183
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• 2011

The radioprotective efficacy of a methanol extract of the red algae Polyopes lancifolia (Harvey) kawaguchi et wang (mPL) was evaluated in mice subjected to total-body gamma irradiation. mPL protection against radiation-induced oxidative stress was examined by histological evaluation of intestinal crypt-cell survival and liver activities of the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). mPL (100 mg/kg body weight) administered intraperitoneally at 24 h and 1 h prior to irradiation protected jejunal crypt cells from radiation-induced apoptosis (p < 0.01). The pretreatment of mPL attenuated a radiation-induced decrease in villous height (p < 0.05), and improved jejunal crypt survival (p < 0.05). The dose reduction factor was 1.14 at 3.5 days after irradiation. Treatment with mPL prior to irradiation resulted in significantly higher (p < 0.01) levels of SOD and CAT activities, compared to those levels of irradiated control mice with vehicle treatment. These results suggest that mPL is a useful radioprotective agent capable of defending intestinal progenitor cells against total-body irradiation, at least in part through mPL antioxidative activity.

• Korean journal of food and cookery science
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• v.24 no.1
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• pp.114-120
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• 2008

In this study, the effects of gamma irradiation on the microbial, physical characteristics, sensory qualities and antioxidant activity of Kongnamul Muchim(cooked soybean sprouts) were investigated. Gamma irradiation at 3 kGy inhibited microbial growth until 4 weeks of storange at $4^{\circ}C$ and until 5 days at and $25^{\circ}C$. The 3 kGy dose did not significantly affect the hardness of the sprouts; however Hunter's color values for lightness, redness and yellowness were changed. Low-dose gamma irradiation(up to 2 kGy) did not significantly affect the antioxidant activity of the Kongnamul Muchim. Also, based on a triangle sensory test, the gamma irradiated Kongnamul Muchim was not significantly different from the control. From these results, it is suggested that the applying gamma irradiation to cooked vegetables at doses lower than 3 kGy is recommended to extend shelf-life and maintain quality characteristics.

• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.741-745
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• 2002

Effect of gamma irradiation on inhibition of microbial growth and reduction of residual nitrite level in cooked pork sausage were studied during 4 weeks of storage at $4^{\circ}C$. Irradiation at 5 and 10 kGy significantly reduced the number of total aerobic bacteria and almost eliminated coliform bacteria. Irradiation reduced the content of residual nitrite in cooked pork sausage in a dose-dependent manner, and among packaging methods, the sausage with $CO_2$ (100%) packaging was the lowest level of residual nitrite. Results indicate that the irradiation combined with packaging is a useful technology to reduce the residual nitrite in cooked pork sausage.