• Journal of Radiation Industry
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• v.3 no.1
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• pp.25-29
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• 2009

Microarrays can be used to screen thousands of binding events in a parallel and high throughput fashion and are of major importance in disease diagnosis and drug discovery. The use of radioisotope is conventionally regarded as one of the most sensitive detection methods. Atherosclerosis is a common disorder affecting arterial blood vessels. It happens when fat, cholesterol, and other substances made in the arterial blood vessels form a hard substances called plaque. Lipoprotein-associated phospholipase $A_2$ ($Lp-PLA_2$), a phospholipase $A_2$ enzyme, is used as a marker for cardiac disease. The detection of $Lp-PLA_2$ was accomplished by using radioactive [$^3H-acetyl$] PAF as a substrate and a feasibility study on RI biochip application to detection of $Lp-PLA_2$, a risk factors of atherosclerosis was performed. Inhibitive activity of a native plant extract was also determined by using the RI biochip. It was found to be applicable to a high-throughput screening of inhibitors for developing atherosclerosis therapeutic agents.

• Radiation Oncology Journal
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• v.31 no.2
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• pp.88-96
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• 2013

Purpose: This study identifies accident sequences from the past accidents in order to help the risk analysis application to the external radiotherapy. Materials and Methods: This study reviews 59 accidental cases in two retrospective safety analyses that have collected the incidents in the external radiotherapy extensively. Two accident analysis reports that accumulated past incidents are investigated to identify accident sequences including initiating events, failure of safety measures, and consequences. This study classifies the accidents by the treatments stages and sources of errors for initiating events, types of failures in the safety measures, and types of undesirable consequences and the number of affected patients. Then, the accident sequences are grouped into several categories on the basis of similarity of progression. As a result, these cases can be categorized into 14 groups of accident sequence. Results: The result indicates that risk analysis needs to pay attention to not only the planning stage, but also the calibration stage that is committed prior to the main treatment process. It also shows that human error is the largest contributor to initiating events as well as to the failure of safety measures. This study also illustrates an event tree analysis for an accident sequence initiated in the calibration. Conclusion: This study is expected to provide sights into the accident sequences for the prospective risk analysis through the review of experiences.

• Journal of Veterinary Clinics
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• v.37 no.1
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• pp.15-22
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• 2020

This study investigated the effectiveness of radiation safety rules in animal hospital and the awareness and behavior of veterinary radiation workers. With the questionnaires, the data was collected from randomly selected veterinarians in animal hospitals and animal medical imaging centers. Collected data were about radiation device, shielding device, regulations, safety management, education, knowledge, behavior and awareness. Frequency, correlation and multiple regression analysis were performed. The medical devices related with radiation in animal hospital were X-ray (59%), CT (15%), fluoroscopy (12%), mobile X-ray (12%) and others (2%). The number of people using radiation shielding device is high. The answers were low on knowing radiation related regulation and receiving radiation protection education. The group with higher knowledge and awareness shows positive correlation with safety behavior. The increase of use of the radiation related medical devices in veterinary hospital causes the increase of radiation exposure risk. This study suggests that radiation safety management system and policies need to be developed to protect radiation workers and give them correct information and consciousness.

• The Journal of the Korean dental association
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• v.52 no.3
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• pp.147-152
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• 2014

Recently the patient exposure by medical and dental x-ray examination has grown rapidly and diagnostic radiology represents the largest source of man-made radiation. For the patient protection, the principle of justification and optimization should be followed. All the radiographic examinations have to show a potential benefit to the patient weighing against the potential risk. After they are justified, the radiographic exposure should be kept as low as reasonably achievable, taking into account economic and social factors. For the safe use of radiation in dentistry, the radiation safety management in accordance with the legislation is important. The present status and the future of radiation safety management in dental radiology in Korea and other country will be discussed.

• Nuclear Medicine and Molecular Imaging
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• v.43 no.4
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• pp.259-279
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• 2009

Radioiodine ablation therapy has been considered to be a standard treatment for patient with differentiated thyroid cancer after total thyroidectomy. Patients may need to be hospitalized to reduce radiation exposure of other people and relatives from radioactive patients receiving radioiodine therapy. Medical staffs, nursing staffs and technologists sometimes hesitate to contact patients in radioiodine therapy ward. The purpose of this paper is to introduce radiation dosimetry, estimate radiation dose from patients and emphasize the safety of radiation exposure from patients treated with high dose radioiodine in therapy ward. The major component of radiation dose from patient is external exposure. However external radiation dose from these patients treated with typical therapeutic dose of 4 to 8 GBq have a very low risk of cancer induction compared with other various risks occurring in daily life. The typical annual radiation dose without shielding received by patient is estimated to be 5 to 10 mSv, which is comparable with 100 to 200 times effective dose received by chest PA examination. Therefore, when we should keep in mind the general principle of radiation protection, the risks of radiation exposure from patients are low and the medical personnel are considered to be safe from radiation exposure.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.3
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• pp.1207-1211
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• 2015

Background: Breast cancer is by far the most frequent cancer of women (23 % of all cancers), ranking second overall when both sexes are considered together. Contralateral breast cancer (CBC) is becoming an important public health issue because of the increased incidence of primary breast cancer and improved survival. The present communication concerns a study to evaluate the role of various clinico-pathological factors on the occurrence of contralateral breast cancer. Materials and Methods: A detailed analysis was carried out with respect to age, menopausal status, family history, disease stage, surgery performed, histopathology, hormone receptor status, and use of chemotherapy or hormonal therapy. The diagnosis of CBC was confirmed on histopathology report. Relative risk with 95%CI was calculated for different risk factors of contralateral breast cancer development. Results: CBC was found in 24 (4.5%) out of 532 patients. Mean age of presentation was 43.2 years. Family history of breast cancer was found in 37.5% of the patients. There was statistically significant higher rate (83.3%) of CBC in patients in age group of 20-40 years with RR=11.3 (95% CI: 1.4, 89.4, p=0.006) seen in 20-30 years and RR=10.8 (95% CI:1.5-79.6, p=0.002) in 30-40 years as compared to older age of 60-70 years. Risk of development was higher in premenopausal women (RR=8.6, 95% CI: 3.5-21.3, $p{\leq}0.001$). Women with family history of breast cancer had highest rate (20.9%) of CBC (RR=5.4, 95% CI: 2.5-11.6, $p{\leq}0.001$). Use of hormonal therapy in hormone receptor positive patients was protective factor in occurrence of CBC but not significant (RR=0.7, 95% CI: 0.3-1.5, p=0.333). Conclusions: Younger age, premenopausal status, and presence of family history were found to be significant risk factors for the development of CBC. Use of hormonal therapy in hormone receptor positive patients might be protective against occurrence of CBC but did not reach significance.

• Korean Journal of Digital Imaging in Medicine
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• v.16 no.1
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• pp.43-47
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• 2014

Sens of insecutity of the public and professionals about harmful effects of radiation is increasing in an accident at the Chernobyl and Fkushima nuclear power plant.Anxiety was amplified to lack of information about radiation majority of people. To target the middle and high school in the region of Daegu and Gyeongsangbuk-do, to investigate the radiation recognition of the next generation, it is intended to present a model of education for the safe use of radiation. The High School of the six metropolitan cities, city, town through the questionnaire and needs to be educational experience of radiation and use knowledge level of radiation, experience in daily life, understanding of man-made radiation and natural radiation, information channel on radiation, the radiation Distribute the total 800 parts of, to recover the 629 unit, was analyzed for 155 females 474 males. Many people 75.36% of the people, to 24.64% female subjects of this investigation, was constant, respectively from 13 to 18 years age. It is a large number and 30.37% of the respondents as "normal" level of knowledge of radiation, for the type of radiation, most knew. You have answer for risk experience of the medical radiation was higher, touching a lot of information via the broadcast medium in general, and the accuracy is low. I thought we wanted to be educated three or more twice a year, as an educator,about 71.37% and radiation-related understanding of knowledge and background in accordance with the diversification of information channels, the regional differences between urban and rural areas. But I considered the difference age (grade) for each is displayed, intended for junior high school students, the target surface and use the occurrence of radiation, high school students, the need for education about risk and application of radiation through this study.

• Radiation Oncology Journal
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• v.29 no.2
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• pp.71-82
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• 2011

Purpose: To evaluate the biochemical control rate and the rate of side effects after performing permanent brachytherapy of localized prostate cancer. Materials and Methods: 67 patients with localized prostate cancer were treated with brachytherapy between April 2007 and December 2008. Of these, 43 patients who were followed up and did not receive external radiotherapy were evaluated for the change in prostate specific antigen (PSA) level and the occurrence of side effects. In total, 18 patients were classified as low risk, 19 patients as intermediate risk, and 6 patients as high risk. The prescription dose was 145 Gy. Results: A PSA increase greater than 2 ng/mL occurred in 2 patients (4.7%). Radiation Therapy Oncology Group (RTOG) grade 1 and 2 acute urologic complications (UC) occurred in 40 and 3 patients, respectively. Further, 5 patients had RTOG grade 1 acute rectal complication (RC). The numbers of RTOG grade 1, 2, and 3 chronic UC were 1, 4, and 1, respectively. The numbers of RTOG grade 1, 2, and 4 chronic RC were 5, 10, and 3, respectively. The statistically significant risk factors (RF) of acute RC were the minimal dose in the most irradiated 0.1 cc volume ($D_{0.1cc}$, p=0.041) and absolute volume receiving 150% of the prescribed dose ($V_{150cc}$, p=0.038) in the entire rectum (ER). The percentage ($V_{100%}$, p=0.019) and absolute volume ($V_{100cc}$, p=0.047) in the involved rectum (IR) were also statistically significant. The RF of chronic RC were $V_{100%}$ (p=0.011) in the ER and the $D_{0.1cc}$ (p=0.049), $V_{100cc}$ (p=0.023) in the IR. The number of used seeds were related with acute UC (p=0.028). Conclusion: Permanent brachytherpy of localized prostate cancer showed a favorable short term biochemical control rate. As such, selective intermediate and high risk patients can be managed with permanent brachytherapy. The effort to reduce rectal complication is also necessary.

• Journal of Preventive Medicine and Public Health
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• v.43 no.2
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• pp.185-192
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• 2010

Objectives: We conducted a meta-analysis to investigate the relationship between low external doses of ionizing radiation exposure and the risk of cancer mortality among nuclear power plant workers. Methods: We searched MEDLINE using key words related to low dose and cancer risk. The selected articles were restricted to those written in English from 1990 to January 2009. We excluded those studies with no fit to the selection criteria and we included the cited references in published articles to minimize publication bias. Through this process, a total of 11 epidemiologic studies were finally included. A publication bias was tested for using Egger's test. The homogeneity test was performed before the integration of each of the standardized mortality ratios (SMRs) and the result proved that the studies were heterogeneous. Results: We found significant decreased deaths from all cancers (SMR = 0.75, 95% CI = 0.62 - 0.90), all cancers excluding leukemia, solid cancer, mouth and pharynx, esophagus, stomach, rectum, liver and gallbladder, pancreas, lung, prostate, lymphopoietic and hematopoitic cancer. The findings of this meta-analysis were similar with those of the 15 Country Collaborative Study conducted by the International Agency for Research on Cancer. A publication bias was found only for liver and gallbladder cancer (p = 0.015). Heterogeneity was observed for all cancers, all cancers excluding leukemia, solid cancer, esophagus, colon and lung cancer. Conclusions: Our findings of low mortality for stomach, rectum, liver and gallbladder cancers may explained by the health worker effect. Yet further studies are needed to clarify the low SMR of cancers, for which there is no useful screening tool, in nuclear power plant workers.

• Radiation Oncology Journal
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• v.11 no.2
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• pp.337-346
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• 1993

This is a retrospective cohort analysis of 58 patients who treated with postoperative radiation therapy following radical hysterectomy and bilateral pelvic adenectomy for early stage carcinoma of uterine cervix between January 1988 and December 1990 at department of radiation oncology, Keimyoung University Hospital. Sixteen percent of patients (9/58) had chemotherapy. Most patients were FIGO I b (47 patients), and FIGO I a and II a were one and ten patients, respectively. The median follow-up periods were 48.5 months. The indications for radiation therapy included pelvic lymph node metastasis, large tumor size, deep stromal invasion, lymphovascular invasion, positive surgical margin, endometrial invasion and parametrial invasion. Eighty five percent of the patients had more than one risk factor. The actuarial overall five year survival rate (5 YSR) and five year disease free survival rate (5 YDFSR) were $89.5\%,\;and\;87.8\%,$ respectively. Their overall recurrence rate was $12.1\%,$(758). Distant metastasis was the most common cause of treatment failure $(71.4\%:5/7).$ The univariate analysis of prognostic factors affecting to five year survival rate disclosed pelvic lymph node status (negative: $95.5\%,\;positive:69.2\%,$ p=0.006) and hemoglobin level $(\le11 :75\%,>11g/dl:93.3\%,p=0.05)$ as significant factor. The age status was marginally significant $(\le40:96.0\%,\;>\;40:84.3\%p=0.15).$ Multivariate analysis clarified three independent prognostic factors: pelvic lymph node metastasis (p=p.006), hemoglobin level (p=0.015) and age (p=0.035). Multivariate analysis of prognostic factor affecting to five year disease free survival rate disclosed pelvic lymph node status (p=0.0078) and status of surgical margin (p=0.008). Complications relating to radiotherapy were $10.3\%,(6/58).$ There were no severe major complication requiring surgical intervention or a long hospital stay. It is our opinion that the benefit of postoperative pelvic radiotherapy may be gained in such a high risk patient population with acceptible morbidity.