• Journal of Radiation Protection and Research
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• 제37권2호
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• pp.90-95
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• 2012

Radiocaesium과 radiostrontium에 대한 벼의 흡수억제 대책으로서 K와 Ca의 동시처리 효과를 조사하기 위하여 온실 내에서 방사성 추적자 실험을 수행하였다. 흙상자에 담긴 논토양(pH 6.5의 양토)에 $^{137}Cs$와 $^{85}Sr$을 가하고 농업용 KCl과 $Ca(OH)_2$를 사용하여 K와 Ca를 처리한 다음 모내기하였다. 대조 작물체의 쌀알에 대한 $^{137}Cs$와 $^{85}Sr$의 토양-작물체전이계수(TF, $m^2\;kg^{-1}-dry$)는 각각 $7.4{\times}10^{-5}$ 및 $2.1{\times}10^{-4}$였고 볏짚의 경우에는 각각 $2.6{\times}10^{-4}$ 및 $2.2{\times}10^{-2}$였다. K와 Ca의 동시처리 수준(K/Ca, $g\;m^{-2}$)이 $^{137}Cs$의 경우 33.6/322까지, $^{85}Sr$의 경우 48.0/460까지 증가할수록 전이계수가 점점 감소하였다. 최고 감소율은 두 핵종 모두 60% 정도였다. $^{85}Sr$ 전이계수는 33.6/322 처리에서도 60% 가까이 감소하였다. 당 처리에서는 벼의 생산성도 양호하였다. 이로써 본 실험에서는 33.6/322 처리가 최적인 것으로 판단되었다. 최적 처리 수준은 각종 요인에 따라 다를 수 있으므로 차후 다양한 조건에 대한 실험이 수행될 필요가 있다.

• Radiation Oncology Journal
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• 제33권2호
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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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• 제32권1호
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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.

• 한국식품영양과학회지
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• 제40권5호
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• pp.712-716
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• 2011

본 연구에서는 해조류에 대한 방사선의 영향 평가에 관하여 알아보기 위하여 감마선 조사된 미역귀로부터 추출된 조다당의 추출수율 및 미백활성에 관하여 관찰하였다. 미백활성은 melanin 합성에 중요하게 작용하는 tyrosinase 억제활성과 melanocyte의 melanin 생성 억제능을 평가하였다. 실험 결과, 방사선의 조사는 선량 의존적으로 조다당의 추출수율을 증가시키고, tyrosinase 억제 활성 및 ${\alpha}$-MSH로 melanin을 과생성 시킨 B16BL6 melanoma 세포내 melanin 생성 억제 활성을 유지시켜 주는 것으로 나타났다. 이러한 결과로 미루어 보아 감마선의 조사는 미백활성을 갖는 미역귀 조다당을 얻기 위한 효과적인 방법이며, 미백 산업 분야에서도 효과적으로 이용될 수 있을 것으로 사료된다.

• 폴리머
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• 제30권1호
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• pp.10-13
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• 2006

의료용 등급의 폴리프로필렌 수지에 감마선을 조사한 후 내방사선성에 대한 산화방지제와 열처리의 효과에 대해 연구하였다. 폴리프로필렌과 여러 종류의 산화방지제를 혼합하고 이를 시이트 형태로 제작하여 질소분위기에서 25 kGy로 감마선 조사하였다. 감마선을 조사한 폴리프로필렌 시이트에 대해 산화방지제 종류 및 함량에 따른 색도 변화와 기계적 강도 변화를 조사하였으며 감마선 조사 후의 열처리 조건에 따른 라디칼 잔존량과 산화지수의 변화를 측정하였다. 페놀계 및 아민계 산화방지제보다는 인계 산화방지제를 폴리프로필렌에 혼합하였을 때 감마선 조사 후 색도 변화를 최소화할 수 있었다. $130\;^{\circ}C$에서 30분 동안의 열처리에 의해 산화의 원인이 되는 자유라디칼을 충분히 제거할 수 있어 열처리하지 않은 폴리프로필렌보다 낮은 산화지수를 얻을 수 있었다.

• Journal of Radiation Protection and Research
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• 제44권2호
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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.

• 한국산림과학회지
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• 제87권4호
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• pp.601-610
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• 1998

본 연구는 시설에서 자란 콘테이너 묘목(苗木)의 경화과정(硬化過程)에 UV-B의 이용 가능성을 탐색하고자 생장상(生長箱)에서 4개월간 생육(生育)시킨 자작나무 묘목을 대상으로 UV-$B_{BE}$ $3.2KJ\;m^{-2}\;day^{-1}$과 $5.2KJ\;m^{-2}\;day^{-1}$ 수준의 UV-B 처리와 수분(水分)스트레스 처리(處理)를 4주간 실시하여 경화처리 전(前), 후(後)의 생장(生長) 및 생리적(生理的) 특성을 비교 분석하였다. UV-B 또는 수분스트레스 처리는 수고생장(樹高生長), 잎의 건물량축적(建物量蓄積)을 감소시켰다. UV-B 처리는 근원경생장(根元徑生長)을 감소시켰으나 수분스트레스 처리는 근원경생장을 증진시켰다. UV-B 처리 또는 수분스트레스 처리에 의한 잎의 건물량감소는 묘목의 T/R율을 감소시켰다. T/R율의 감소효과는 수분스트레스 처리에서 가장 크게 나타났다. 엽록소(葉緣素) 지수(指數)는 UV-B 5.2에서 가장 낮았으며 UV-B 3.2와 수분스트레스 처리에서는 비슷한 수준이었다. UV-B 또는 수분스트레스 처리는 콘테이너 묘목의 함수율(含水率)과 수분포텐셜을 낮추었으며 삼투압(滲透壓)을 높혔다. 경화처리에 의한 잎과 줄기의 함수율 감소는 UV-B 처리에 의해서는 빠르게 일어났으나 수분스트레스 처리에 의해서는 보다 서서히 일어났다. 이상의 결과를 보면, 자작나무 콘테이너 묘목의 경화단계에 처리된 UV-B에 의한 생장반응(生長反應) 및 수분생리(水分生理) 변화는 수분스트레스 처리에서의 효과와 유사한 면이 관찰되었다.

• 대한간호학회지
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• 제29권6호
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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).

• 대한핵의학회지
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• 제32권5호
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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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• 제20권1호
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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.