• Radiation Oncology Journal
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• v.33 no.2
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• pp.109-116
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• 2015

Purpose: To analyze prognostic factors for locoregional recurrence (LRR), distant metastasis (DM), and overall survival (OS) in cervical cancer patients who underwent radical hysterectomy followed by postoperative radiotherapy (PORT) in a single institute. Materials and Methods: Clinicopathologic data of 135 patients with clinical stage IA2 to IIA2 cervical cancer treated with PORT from 2001 to 2012 were reviewed, retrospectively. Postoperative parametrial resection margin (PRM) and vaginal resection margin (VRM) were investigated separately. The median treatment dosage of external beam radiotherapy (EBRT) to the whole pelvis was 50.4 Gy in 1.8 Gy/fraction. High-dose-rate vaginal brachytherapy after EBRT was given to patients with positive or close VRMs. Concurrent platinum-based chemoradiotherapy (CCRT) was administered to 73 patients with positive resection margin, lymph node (LN) metastasis, or direct extension of parametrium. Kaplan-Meier method and log-rank test were used for analyzing LRR, DM, and OS; Cox regression was applied to analyze prognostic factors. Results: The 5-year disease-free survival was 79% and 5-year OS was 91%. In univariate analysis, positive or close PRM, LN metastasis, direct extension of parametrium, lymphovascular invasion, histology of adenocarcinoma, and chemotherapy were related with more DM and poor OS. In multivariate analysis, PRM and LN metastasis remained independent prognostic factors for OS. Conclusion: PORT after radical hysterectomy in uterine cervical cancer showed excellent OS in this study. Positive or close PRM after radical hysterectomy in uterine cervical cancer correlates with poor prognosis even with CCRT. Therefore, additional treatments to improve local control such as radiation boosting need to be considered.

• Radiation Oncology Journal
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• v.32 no.1
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• pp.7-13
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• 2014

Purpose: To evaluate the results of postoperative radiotherapy in patients with extra-hepatic bile duct cancer (EHBDC) and identify the prognostic factors for local control and survival. Materials and Methods: Between January 2001 and December 2010, we retrospectively reviewed the cases of 70 patients with EHBDC who had undergone curative resection and received postoperative radiotherapy. The median radiation dose was 50.4 Gy (range, 41.4 to 54 Gy). The resection margin status was R0 in 30 patients (42.9%), R1 in 25 patients (35.7%), and R2 in 15 patients (21.4%). Results: The 5-year rates of overall survival (OS), event-free survival (EFS), and locoregional control (LRC) for all patients were 42.9%, 38.3%, and 61.2%, respectively. The major pattern of failure was distant relapses (33 patients, 47.1%). A multivariate analysis showed that the postradiotherapy CA19-9 level, radiation dose (${\geq}50$ Gy), R2 resection margins, perineural invasion, and T stage were the significant prognostic factors for OS, EFS, and LRC. OS was not significantly different between the patients receiving R0 and R1 resections, but was significantly lower among those receiving R2 resection (54.6%, 56.1%, and 7.1% for R0, R1, and R2 resections, respectively). Conclusion: In patients with EHBDC who had undergone curative resection, a postoperative radiotherapy dose less than 50 Gy was suboptimal for OS and LRC. Higher radiation doses may be needed to obtain better LRC. Further investigation of novel therapy or palliative treatment should be considered for patients receiving R2 resection.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.712-716
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• 2011

We investigated changes in the extraction yield and whitening activity of polysaccharides from Undaria pinnatifida sporophyll due to gamma irradiation. U. pinnatifida sporophyll was gamma-irradiated at doses of 10, 30, 50, 70, and 100 kGy, then extracted with hot water and precipitated with ethanol to extract polysaccharides. Crude polysaccharide yields increased with an increase in irradiation dosage, but tyrosinase inhibition activity did not change. Melanin synthesis did not significantly differ between B16BL6 cells treated with irradiated and non-irradiated samples. In conclusion, gamma irradiation increased the crude polysaccharide extraction yield but did not change the whitening activity of U. pinnatifida sporophyll. This implies that gamma irradiation can be used to increase yields in the cosmetic industry, thus increasing profits.

• Polymer(Korea)
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• v.30 no.1
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• pp.10-13
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• 2006

The effects of antioxidants and thermal treatment on the radiation resistance of the gamma-ray irradiated polypropylene (PP) were studied. The PP was blended with various antioxidants and was fabricated into a sheet. The PP sheet was irradiated with gamma-ray to a dosage of 25kGy in the nitrogen atmosphere. The differences in both color and mechanical strength were investigated for the gamma-ray irradiated PP depending on the kind and the content of antioxidant. The residual amount of free radical and the variation of oxidation index were investigated for the gramma-ray irradiated PP with thermal treatment after irradiation. The PP having phosphite antioxidant showed little difference in color after gamma-ray irradiation compared with the PP having phenolic or mine antioxidant. Sufficient amount of free radical could be removed from the gamma-ray irradiated PP by the thermal treatment at $130\;^{\circ}C$ for 30 min. Thermally treated PP showed lower oxidation index than the PP without thermal treatment.

• Journal of Radiation Protection and Research
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• v.44 no.2
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• pp.72-78
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• 2019

Background: In the calibration and testing laboratory of Korea Atomic Energy Research Institute, the old X-ray generator used for the production of reference X-ray fields was replaced with a new one. For this newly installed X-ray irradiation system, beam alignment as well as the verification of beam qualities was conducted. Materials and Methods: The existing X-ray generator, Phillips MG325, was replaced with YXLON Y.TU 320-D03 in order to generate reference X-ray fields. Theoretical calculations and Monte Carlo simulations were used to determine initial filter thickness. Beam alignment was performed in three steps to deliver a homogeneous radiation dosage to the target at different distances. Finally, the half-value layers were measured for different X-ray fields to verify beam qualities by using an ion chamber. Results and Discussion: Beam alignment was performed in three steps, and collimators and other components were arranged to maintain the uniformity of the mean air kerma rate within ${\pm}2.5%$ at the effective beam diameter of 28 cm. The beam quality was verified by using half-value layer measurement methods specified by American National Standard Institute (ANSI) N13.11-2009 and International Organization for Standardization (ISO)-4037. For each of the nine beams than can be generated by the new X-ray irradiation system, air kerma rates for X-ray fields of different beam qualifies were measured. The results showed that each air kerma rate and homogeneity coefficient of the first and second half-value layers were within ${\pm}5%$ of the recommended values in the standard documents. Conclusion: The results showed that the new X-ray irradiation system provides beam qualities that are as high as moderate beam qualities offered by National Institute of Standards and Technology in ANSI N13.11-2009 and those for narrow-spectrum series of ISO-4037.

• Journal of Korean Society of Forest Science
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• v.87 no.4
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• pp.601-610
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• 1998

This study was carried out to investigate the possibility of supplemental UV-B application to the hardening phase of container-grown Betula platyphylla seedlings. The containerized seedlings were grown in a growth chamber for four months and then treated with UV-B(UV-$B_{BE}$ $3.2KJ\;m^{-2}\;day^{-1}$ and $5.2KJ\;m^{-2}\;day^{-1}$) radiation and water stress regime(irrigation in one week interval) for four weeks. The differences in growth and physiological responses of the seedlings before and after the treatments were analyzed. UV-B radiation and water stress reduced height growth and leaf dry mass accumulation of the seedlings. The root collar diameter growth was reduced by UV-B radiation but increased by water stress. The reduction in leaf dry weight by UV-B radiation and water stress reduced T/R ratio of the seedling. The reduction in T/R ratio was the most apparent by water stress. Chlorophyll index observed by a chlorophyll meter was the lowest in the $5.2KJ\;m^{-2}\;day^{-1}$ of UV-B radiation, and those in the $3.2KJ\;m^{-2}\;day^{-1}$ and water stress were similar. UV-B radiation and water stress reduced both water content in the seedlings and leaf water potential, and increased leaf osmatic pressure. The water content of leaves and shoots was reduced more rapidly by UV-B radiation than by water stress treatment. In conclusion, growth responses and physiological changes in water relation by supplemental UV-B radiation which was applied to the hardening phase of container-grown Betula platyphylla seedlings were similar results to the water stress treatment.

• Journal of Korean Academy of Nursing
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• v.29 no.6
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• pp.1179-1191
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• 1999

This study was conducted to identify appetite and nutritional status of 48 cancer patients who have been irradiated over 150$\textrm{cm}^2$ on chest or pelvic area over the three-month period. The data were gathered 3 phases, Each from initiation to completion of radiotherapy through the questionnaires of anorexia, the anthropometric and biochemical measures were used such as weight, TSF, MAC, MAMC, serum albumin and hemoglobin, TLC. Using SAS program, data were analyzed by percentage, Mean$\pm$SD, and two-way repeated measures ANOVA. The results were summarized as follows : 1. Eighty five percent(85%) of the subjects were aged from fifties to sixties. Cancers in the chest area occurred in 100% of men, 56% of the all subjects. The other 44% were pelvic cancer and 71% of the pelvic cancer occurred in women. 2. There were no significant differences in the appetite scores by all groups(characteristics). Changes of the appetite score over time were statistically significant by age, sex, cancer areas staging, treatment modality, and radiation dosage (F=4.0, p=.022; t=6.09, p=.003; t=4.90, p=.009; F=3.28, p=.042; t=5.04, p=.0084; t=4.76, p=.011). The appetite score on the 2nd phase (4 weeks after initiating radiotherapy) decreased from the 1st phase (initiating irradiation), and then increased on the 3rd phase (completing irradiation). 3. There were no significant differences in the body weight and MAMC by all characteristics, and no changes in the body weight and MAMC over time. However there were significant differences of TSF, MAC, level of hemoglobin, level of albumin, and TLC by all characteristics during the three phases. TSF of the men and the chest cancer were lower than those of the women and the pelvic cancer (t=73.20, p=.0001; t=22.91, p=.0001). And there was significant difference by cancer staging(F=3.19, p=.050). But there was no change in TSF over time. MAC of the men and the chest cancer were lower than those of the women and the pelvic cancer each(t=9.23, p=.004; t=17.85, p=.0001). But no change in MAC over time. Levels of hemoglobin had significant differences by age, sex and cancer areas; levels of hemoglobin of older than the fifties, men, and chest area were higher than those on the others(F=3.82, p=.029; t=21.75, p=.0001; t=8.71, p=.005). Levels of albumin were significant differences by sex and cancer areas; levels of albumin on women, and pelvic area were higher than those on the others(t=6.34, p=.015; t=15.23, p=.0003). While the levels of hemoglobin were changed over time, levels of albumin were not changed and within normal limit. TLC of the men was higher than women(t=5.05, p=.029). Changes in the level of hemoglobin over time were statistically significant according to sex, cancer areas, and radiation dosage(t=3.49, p=.035; t=3.36, p=.039; t=4.04, p=.021).

• The Korean Journal of Nuclear Medicine
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• v.32 no.5
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• pp.436-442
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• 1998

Radioactive iodine treatment has been widely used for nearly 50 years in the treatment of thyroid cancer to ablate residual thyroid tissue after thyroidectomy and to treat metastatic disease. Leukemia is a rare complication associated with the radioactive iodine therapy. The occurrence of leukemia is known to be related to the cumulative dosage of I-131 more than 37 GBq (1 Ci) and also associated with the intervals of less than 12 months between the repeated doses. We report a case of a 52 year-old female patient with papillary cancer of thyroid who developed acute myelogenous leukemia after the total 20.4 GBq (550 mCi) of I-131 therapy over 3.2 years and palliative radiation therapy (3000 cGy) due to multiple bone metastasis of papillary cancer.

• Toxicological Research
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• v.20 no.1
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• pp.21-29
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• 2004

We used cDNA microarray to assess gene expression profiles in hematopoetic cell line, U-937, exposed to low doses of ionizing irradiation. The 1,000 DNA elements on this array were PCR-amplified cDNAs selected from named human cancer related genes. According to the strength of irradiation, the levels of some gene expression were increased or decreased as dose-dependent manner. The gene expressions of Tubulin alpha, protein kinase, interferon-alpha, -beta, -omega receptor and ras homolog gene family H were significantly increased. Especially, Tubulin gene was shown 2.5 fold up-regulated manner under stress of 500 rad irradiation than 200 rad. On the other hand, fibroblast growth factor 12 and four and a half LIM domains, etc. were significantly down-regu-lated. Also, tumor protein 53(TP53) related genes that p53 inducible protein, tumor protein 53-binding protein looks of little significance as radiation sensitive manner. The radio-sensitivity of tubulin gene etc. that we proposed could be useful to rapid and correct survey for the bio-damage by exposure to low dose irradiation.

• Nuclear Engineering and Technology
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• v.7 no.4
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• pp.277-284
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• 1975

A result of measurement for the relative dose distribution of neutron gamma mixed radiation field in the biological irradiation facility installed at TRIGA Mark-III reactor is described. The relative dose distributions of neutron-gamma mixed radiation field in the biological exposure room have been experimentally determined using a thermoluminescent dosimeter. Presented herein in graphical forms are the experimental results obtained. It as observed that the region commonly having the characteristics of rather homogeneous horizontal and lateral dose distributions is confined to the area bounded by the two planes horizontally parallel to the beam direction with heights of about 40 cm and 130 cm, respectively, at distances beyond 100 cm from the segmentary surface of the aluminum pool liner projected into the the exposure room, while other areas show a steeper gradient in dosage, especially the places adjacent to the segment of the aluminum pool liner and near the inner po${\gamma}$lion of the concrete walls of the exposure room.