• Radiation Oncology Journal
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• v.21 no.1
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• pp.10-18
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• 2003

Purpose : To evaluate the role of fractlonated sterotactic radiotherapy (FSRT) in the management of benign brain tumors, we reviewed the clinical, and radiographic responses of patients treated. Methods and Materials : Between March 1995 and March 2002, 36 patients with benign brain tumors were treated by FSRT. The pathological diagnoses consisted of pituitary adenomas (12 patients), cranio-pharyngiomas (5 patients), meningiomas (10 patients), and acoustic neurinomas (9 patients). Radiotherapy doses of 25 to 35 Gy (3~6 Gy/fraction, 5~10 fractions) were prescribed to the 85~90% isodose line, depending upon the location, size and volume of the tumors. The median clinical and radiographical follow up periods were 31 (range, 2~74) and 21 (range, 4~56) months, respectively. Results : In the 35 patients that could be evaluated for their clinical response, 13 (37.1%) were considered improved, 16 (45.7%) stable and 6 (17.2%) worse. Of the 33 patients who had radiographic studies, tumor shrinkage was noted in 17 (51.5%), tumor stabilization in 13 (39.4%), and tumor progression in 3 (9.1%). Of the 17 tumor shrinkage patients, 7 (21.2%) showed a complete response. Acute radiation-induced complications occurred iin 11 (30.6%) patients. Conclusions : FSRT is considered a safe and effective treatment method for begin brain tumors, but large numbers of patients, with relatively long follow-up periods are needed to assess the exact role or effect of FSRT.

• Food Science and Preservation
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• v.16 no.2
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• pp.286-291
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• 2009

Microorganisms in seafood cooking drips were counted and identified. Total viable cell counts were 6.40 and 3.10 log CFU/g in cooking drips of Hizikia fusiformis and Thunnus thynnus, respectively. However, microbial populations fell with increased irradiation doses. In H. fusiformis cooking drips, a 5-log reduction in total aerobic bacteria was obtained by irradiation with 5 kGy. In T. thynnus cooking drips, however, contaminating microorganisms were more resistant to gamma irradiation and only a 1-log reduction was seen. DNA sequence analysis showed that the principal contaminating microorganisms in H. fusiformis and T. thynnus cooking drips were Lactobacillus and Bacillus species, respectively. Therefore, the high irradiation resistance of T. thynnus cooking drips microbes may result from spore formation by Bacillus species.

• Journal of the Korean Society of Radiology
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• v.11 no.7
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• pp.605-610
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• 2017

Unlike adults, cognitive ability and communication are not accurate in pediatric patients. Therefore movement due to psychological anxiety in X-ray photography is one of the factors that increase repeated irradiation. In order to minimize the rejection of X-ray and to improve the satisfaction of medical service, it is necessary to improve the environment of the radiological room to help psychological stability and to find a positive measure for reduction of radiation dose, including unnecessary. The subjects of this study were 186 pediatric patients from May to July, 2017, who were from 6 months to 36 months, The study group was set up a radiological room without auditory and visual environment changes is A group, except for changes in visual environment, the room where only auditory environmental changes were applied was group B, the auditory environment changes were excluded, and the room where only the visual environment change was applied was divided into group C, the auditory and visual environment changes were applied to the D. In group A, 10 retrospectives were obtained, 7 in group B, 5 in group C, and 2 in group D. Especially in group A and group D, statistically significant at p <0.053 In conclusion, hearing and visual environment changes affected the psychological stability of pediatric patient, and the repeated irradiation was reduced, thus improving the quality of medical services.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1432-1438
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• 1998

The gamma-radiation sensitivity of eight kinds of pathogenic bacteria related to beef was investigated in frozen cells $(-18^{\circ}C)$ with 0.1 M phosphate buffer and inoculated cells in beef. In frozen cells, D10 values of pathogenic bacteria related to beef were $0.07{\sim}0.69$ kGy, and inactivation factors were $2.90{\sim}42.86$ at the radiation doses of $2{\sim}3$ kGy. Beef was inoculated with Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Enterobacter aerogenes, Vibrio parahaemolyticus, Staphylococcus aureus, Listeria monocytogenes, and Aeromonas hydrophila. Inoculated beef samples were packaged in air and irradiated at 0.005 to 3.0 kGy. Ninety percent of the viable pathogenic bacteria in beef was eliminated by doses of $0.1{\sim}0.61$ kGy at room temperature, and the inactivation factors were $3.28{\sim}30.0$ kGy at the radiation doses of $2{\sim}3$ kGy. Therefore, irradiation is considered to be an effective method to control pathogenic bacteria in beef.

• Journal of Radiation Protection and Research
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• v.24 no.2
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• pp.93-99
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• 1999

The alkaline single-cell gel electrophoresis (SCGE) assay, called the comet assay, has been applied to the detection of DNA damage from a number of chemical and biological factors in vivo and in vitro. The comet assay is a novel method to assess DNA single-strand breaks, alkali-labile sites in individual cells. The effect of peach kernel extracts on radiation-induced DNA damage in human blood lymphocytes was evaluated by the SCGE assay. The lymphocytes, with or without pretreatment of the extracts, were exposed to 0, 0.1, 0.3, 0.5, 1.0 and 2.0 Gy of $^{60}Co$ gamma ray. Significantly increased tail moment, which was a marker of DNA strand breaks in the comet assay, showed an excellent dose-response relationship. The treatment of the peach kernel extracts reduced the DNA damage by 30 % in irradiated groups as compared to that in non-treated control groups. The result indicates that the extracts shows radioprotective effect on lymphocyte DNA when assessed by the comet assay.

• The Korean Journal of Nuclear Medicine
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• v.33 no.2
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• pp.172-177
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• 1999

Purpose: The purpose of this study was to ascertain whether radiation adaptive response could be induced by Tc-99m-methylene diphosphonate (Tc-99m-MDP) in peripheral lymphocytes of patients undergoing bone scintigraphy. Materials and Methods: Lymphocytes from 22 patients (6 males, 16 females, mean age $50{\pm}14$ years) were collected before and after bone scintigraphy using 740 MBq Tc-99m-MDP Lymphocytes from 10 controls (6 males, 4 females, mean age $43{\pm}7$ years) were also collected. They were exposed to challenge dose of 2 Gy gamma rays using a cell irradiator. Number of ring-form and dicentric chromosomes per 600 cells (chromosomal aberrations) was counted under the light microscope. Results: Chromosomal aberrations in patients before bone scintigraphy ($385.1{\pm}30.5$) was not different from that of controls ($367.8{\pm}36.6$). However, chromosomal aberrations in patients after bone scintigraphy was significantly decreased to $192.6{\pm}22.1$ (p=0.0001). Conclusion: Low dose gamma-irradiation by Tc-99m-MDP used for bone scintigraphy induces a cytogenetic adaptive response in peripheral lymphocytes.

• Journal of radiological science and technology
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• v.40 no.3
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• pp.443-451
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• 2017

Mammography is commonly used for screening early breast cancer. However, mammographic images, which depend on the physical properties of breast components, are limited to provide information about whether a lesion is malignant or benign. Although a dual-energy subtraction technique decomposes a certain material from a mixture, it increases radiation dose and degrades the accuracy of material decomposition. In this study, we simulated a breast phantom using attenuation characteristics, and we proposed a technique to enable the accurate material decomposition by applying weighting factors for the dual-energy mammography based on a photon-counting detector using a Monte Carlo simulation tool. We also evaluated the contrast and noise of simulated breast images for validating the proposed technique. As a result, the contrast for a malignant tumor in the dual-energy weighted subtraction technique was 0.98 and 1.06 times similar than those in the general mammography and dual-energy subtraction techniques, respectively. However the contrast between malignant and benign tumors dramatically increased 13.54 times due to the low contrast of a benign tumor. Therefore, the proposed technique can increase the material decomposition accuracy for malignant tumor and improve the diagnostic accuracy of mammography.

• Journal of Life Science
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• v.19 no.6
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• pp.799-803
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• 2009

The killing of male germ cells by radiation and other toxicants has recently been attributed to apoptosis, but a critical evaluation of the presence of the different features of apoptosis in each epithelial stage has not been performed. In this study, mouse testes exposed to radiation were examined by light microscopy and terminal transferase-mediated end labeling (TUNEL) with periodic acid-Schiff (PAS) stains to determine whether the cells were apoptotic according to several criteria. Apoptosis was easily recognized by the presence of peroxidase-stained, entirely apoptotic bodies. In the TUNEL-positive cells or bodies, the stained products correlated precisely with the typical morphologic characteristics of apoptosis as seen at the light microscopic level. The changes that occurred from 0 to 24 hours after exposing the mice to 2 Gy of gamma-rays (2 Gy/min) were examined. The numbers of apoptotic cells reached a peak at 12 hours after irradiation and then declined. The mice that received 0-8 Gy of gamma-rays were examined 8 hours after irradiation. Dose-response relationships were generated for each stage of the epithelial cycle by counting TUNEL-positive cells. The dose-response curves were linear- quadratic [y=(-0.014${\pm}$0.009)$D^{2}$+(0.31${\pm}$0.697)D+0.3575. Where y=the number of apoptotic cells per seminiferous tubule, and D=the irradiation dose in Gy, $r^{2}$=0.9] and there was a significant relationship between the frequency of apoptotic cells and the radiation dose. Although the maximum response was produced by 8 Gy, even 0.5 Gy induced marked changes. These changes were most pronounced in B spermatogonia of stage V and the spermatocyte at the mitotic cells of stage XII.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.408-412
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• 1984

This study was intended to investigate the physiological effect of gamma irradiation at 50, 100 and 500 Gy on the garlic bulbs stored at low temperature of $3\;{\pm}\;1\;^{\circ}C$ and a relative humidity of 70-80%, and room temperature of $12\;{\pm}\;5\;^{\circ}C$ and a relative humidity of 75-85%, respectively for 10 months. Irradiation treatment stimulated temporary the respiration of garlic, which was greatly affected by storage conditions later. Sprouting of garlic was effectively inhibited in the all irradiated and low temperature groups until 10 months of storage, while the nonirradiated and 50 Gy groups were partially rooted around the 4th month after storage under both conditions. Weight loss and spoilage were shown to be little affected by irradiation until the nonirradiated garlic sprouted, and at the latter stage of storage period, the optimum dose of irradiation showed a significant effect on the reduction of weight loss and spoilage in stored garlic. It was also found that irradiation for sprout inhibition did not influence the firmness of garlic cloves.

• Applied Biological Chemistry
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• v.12
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• pp.83-88
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• 1969

In order to inhibit sprouting of garlics during the storage period and the extend their storage life, garlics were irradiated by gamma-rays $(Co^{60})$ and kept at room temperature. The effects of gammaradiation on sprouting inhibition, chemical contents during storage, and spoilage molds were investigated and the results are as follows. 1. Garlics obtained from Muan showed the shorter dormancy period and sprouted earlier than those from Dangjin. 2. Regarding the radioresistance, some differences were found between garlics from Muan and Dangjin. 3. The sprout of garlics from both areas was completely inhibited at 10 Krad and remarkable effect on sprouting was observed even with 5 Krad in case of garlics from Dangjin. 4. The rates of loss in moisture and weight were lower in irradiated lots than control. 5. Change of sugar content was not observed with ${\gamma}-irradiation$ under 300 Krad. 6. Spores of Aspergillus niger and Aspergillus alliaceus were little germinated at a level of 300 Krad.