• The Journal of Korean Society for Radiation Therapy
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• v.31 no.1
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• pp.17-24
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• 2019

Purpose: The present study aims to assess the level of coherency and the accuracy of Point dose of the Isocenter of VERO, a linear accelerator developed for the purpose of the Stereotactic Body Radiation Therapy(SBRT). Materials and Method: The study was conducted randomly with 10 treatment plans among SBRT patients in Kyungpook National University Chilgok Hospital, using VERO, a linear accelerator between June and December, 2018. In order to assess the equipment's power stability level, we measured the output constancy by using PTW-LinaCheck, an output detector. We also attempted to measure the level of accuracy of the equipment's Laser, kV(Kilo Voltage) imaging System, and MV(Mega Voltage) Beam by using Tofu Phantom(BrainLab, Germany) to assess the accuracy level of geometrical Isocenter. We conducted a comparative analysis to assess the accuracy level of the dose by using an acrylic Phantom($30{\times}30{\times}20cm$), a calibrated ion chamber CC-01(IBA Dosimetry), and an Electrometer(IBA, Dosimetry). Results: The output uniformity of VERO was calculated to be 0.66 %. As for geometrical Isocenter accuracy, we analyzed the error values of ball Isocenter of inner Phantom, and the results showed a maximum of 0.4 mm, a minimum of 0.0 mm, and an average of 0.28 mm on X-axis, and a maximum of -0.4 mm, a minimum of 0.0 mm, and an average of -0.24 mm on Y-axis. A comparison and evaluation of the treatment plan dose with the actual measured dose resulted in a maximum of 0.97 % and a minimum of 0.08 %. Conclusion: The equipment's average output dose was calculated to be 0.66 %, meeting the ${\pm}3%$ tolerance, which was considered as a much uniform fashion. As for the accuracy assessment of the geometric Isocenter, the results met the recommended criteria of ${\pm}1mm$ tolerance, affirming a high level of reproducibility of the patient's posture. The difference between the treatment plan dose and the actual measurement dose was calculated to be 0.52 % on average, significantly less than the 3 % tolerance, confirming that it obtained predicted does. The current study suggested that VERO equipment is suitable for SBRT, and would result in notable therapeutic effect.

• Journal of the Korean Society of Radiology
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• v.14 no.6
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• pp.755-762
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• 2020

This study is desinged to examine the effects of Taheebo(Tabebuia avellanedae) extract on the prostate of male rats as a natural radiation protection agent. Taheebo extract is well known to inhibit cell growth for the cell lines of breast and prostate cancer. In this study, the X-ray 7 Gy was irradiated in the prostate of male rat to identify radiation protection effects by Taheebo Extracts, 1, 7, and 21 Days later, hematological changes, external toxicity assessments(LDH), antioxidant enzyme(SOD) activity changes and tissue change were observed. IR+TH group showed greater lymphocyte levels than the irradiation group, which is believed to affect the hematopoietic immune system's resilience. As a results of the external toxicity assessment, Taheebo extract's toxicity is maximum 18.128±5.16%, minimum 13.6945±4.43%. Taheebo is considered to be of little toxicity. The composition of prostate cell nuclei and cytoplasm in Control and TH group was honogeneous, whereas the cell nucleus cohesion in the prostate in irradiation group and inflammatory reactions in cytoplasm were shown. IR+TH group showed less inflammatory reactions of cytoplasm in the prostate than in the radiation irradiation group, but showed a cohesive phenomenon of cell nuclei. It is judged that Taheebo extract has radiation protection against prostate cells.

• Radiation Oncology Journal
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• v.28 no.1
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• pp.23-31
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• 2010

Purpose: To evaluate the relationship between the normal tissue complication probability (NTCP) of 3-dimensional (3-D) radiotherapy and the radiographic parameters of 2-dimensional (2-D) radiotherapy such as central lung distance (CLD) and maximal heart distance (MHD). Materials and Methods: We analyzed 110 patients who were treated with postoperative radiotherapy for breast cancer. A two-field tangential technique, a three-field technique, and the reverse hockey stick method were used. The radiation dose administered to whole breast or the chest wall was 50.4 Gy, whereas a 45 Gy was administered to the supraclavicular field. The NTCPs of the heart and lung were calculated by the modified Lyman model and the relative seriality model. Results: For all patients, the NTCPs of radiation-induced pneumonitis and cardiac mortality were 0.5% and 0.7%, respectively. The NTCP of radiation-induced pneumonitis was higher in patients treated with the reverse hockey stick method than in those treated by other two techniques (0.0%, 0.0%, 3.1%, p<0.001). The NTCP of radiation-induced pneumonitis increased with CLD. The NTCP of cardiac mortality increased with MHD ($R^2=0.808$). Conclusion: We found a close correlation between the NTCP of 3-D radiotherapy and 2-D radiographic parameters. Our results are useful to reanalyze the previous 2-D based clinical reports about breast radiation therapy complications as a viewpoint of NTCP.

• 대한치주과학회:학술대회논문집
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• 2006.11a
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• pp.165-165
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• 2006

• Journal of Radiation Protection and Research
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• v.40 no.4
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• pp.202-210
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• 2015

The low dose radiation is done for a long period, thus researchers have to know the exact dose distribution for the irradiated mouse. This research has been conducted in order to find out methods in transmitting an exact dose to mouse in a mouse irradiation experiment carried out using $^{137}Cs$ irradiation equipment installed in the DIRAMS (Dongnam Institution of Radiological & Medical Sciences) research center. We developed a single mouse housing cage and shelf with adjustable geometric factors such as distance and angle from collimator. The measurement of irradiated dose showed a maximal 42% difference of absorbed dose from the desired dose in the conventional irradiation system, whereas only 6% difference of the absorbed dose was measured in the self-developed mouse apartment system. In addition, multi mice housing showed much difference of the absorbed dose in between head and body, compared to single mouse housing in the conventional irradiation system. This research may allow further research about biological effect assessment for the low dose irradiation using the self-developed mouse apartment to provide more exact doses which it tries to transmit, and to have more reliability for the biological analysis results.

• Clinics in Shoulder and Elbow
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• v.12 no.2
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• pp.167-172
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• 2009

Purpose: We wanted to evaluate the results of treating acromioclavicular joint dislocation using an AO hook plate. Materials and Methods: Between February 2008 and September 2009, 10 patients underwent implant removal after surgical treatment of acromioclavicular joint dislocation using a AO hook plate. The Constant-Murley scoring system was administered postoperatively for evaluating the clinical results, and simple X-ray was taken for evaluating the state of reduction. Results: All cases showed satisfactory results on the clinical and radiological study. The mean Constant-Murley score at follow-up was 90.5 (range: 84~95). Three patients had some degree of discomfort with the hook plate, but these symptoms were relieved on removal of the plate. The radiological evaluation showed restoration of the vertical displacement of the clavicle in all the patients. No complications occurred such as infection, plate failure or redislocation after removal of the plate. Conclusion: The short term follow-up results of treating acromioclvicular joint dislocation using an AO hook plate were satisfactory both clinically and radiologically.

• Korean journal of food and cookery science
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• v.17 no.6
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• pp.617-624
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• 2001

Gamma irradiation (1-10 kGy) was applied to chicken for the evaluation of their microbiological safety and possible genotoxicity. In 3 kGy-irradiated sample, the growth of psychrophile was inhibited about 1.5 log cycles and no cells were recovered in total microbial counts. All kinds of contaminated microorganism were sterilized by 7 kGy-irradiation. Also, irradiation followed by freeze-storage at the same time was very effective in inhibiting bacterial growth. The genotoxicity of 10 kGy-irradiated chicken was evaluated by Salmonella Typhimurium reversion assay and in vivo micronucleus assay using mouse bone marrow cells. The results were negative in the bacterial reversion assay with S. Typhimurium TA98, TA100, TA1535, and TA1539. Clastogenic effects were not shown in vivo mouse micronucleus assay at 10 kGy-dose tested.

• Journal of Korean Orthopaedic Sports Medicine
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• v.5 no.1
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• pp.75-80
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• 2006

Purpose: To evaluate the efficiency of Acutrak screw fixation for radial head fracture (Mason type 2) without considering the safe Bone of radial head. Materials and Methods: Consecutive seven radial head fracture of Mason type II underwent internal fixation with Acutrak screws from May 2001 to February 2003. The mean follow-up period was 1.2years (ranged, $6 months{\sim}2.5 years$). The mean age of patients was 47 years old (ranged, $36{\sim}60years$ old). The cause of injury were fall down -4 cases and traffic accident -3 cases. The results were evaluated by Mayo Clinic results scoring system. Results: Functional Rating Index of Mayo Clinic was excellent- 2 cases and good- 5 cases. There were no nonunion, loosening, heterotopic ossification, infection or degenerative changes. The postoperative range of motion in elbow joint is nearly full for flexion, extension, pronation and supination in this study Conclusion: Consideration of safe zone is not necessary when Acutrak screws are used for radial head fracture. It seems to be a useful method that Acutrak screw fixation for radial head fracture (Mason type II) could achieve good radiologic and clinical results without influencing proximal radio-ulnar joint and has powerful fixation.

• Korean Journal of Veterinary Research
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• v.41 no.1
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• pp.99-104
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• 2001

To determine if micronucleus (MN) assay could be used to predict the absorbed dose of victims after accidental radiation exposure, we carried out to assess the absorbed dose depending on the numerical changes of MN in human peripheral blood lymphocytes after $^{60}Co\;{\gamma}-rays$ exposure in the range of 0.25 to 1 Gy, respectively. The MNs were observed at very low doses, and the numerical changes according to doses. Satisfactory dose-effect calibration curve is observed after low dose irradiation of human lymphocytes in vitro. When plotting on a linear scale against radiation dose, the line of best fit was $Y=(0.02{\pm}0.0009)+(0.033{\pm}0.010)D+(0.012{\pm}0.012)D^2$. The dose-response curve for MN induction immediately after irradiation was linear-quadratic and has a significant relationship between the frequencies of MN and dose. These data show a trend towards increase of the numbers of MN with increasing dose. The number of MN in lymphocytes that were observed in the control group is $0.1610{\pm}0.0093/cell$. Accordingly, MN assay in human peripheral lymphocytes could be a useful in viva model for studying radio-protective drug sensitivity or screening test, microdosimertic indicator and radiation-induced target organ injury. Since MN assay is simple, rapid and reproducible, it will also be a biodosimetric indicator for individual dose assessment after accidental exposure.

• Journal of Radiation Protection and Research
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• v.18 no.2
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• pp.37-45
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• 1993

Enzyme activity changes in rat blood as biochemical indicator useful for evaluating exposure dose were experimentally studied. The experimental results obtained are as follows: 1) Alkaline phosphatase activities increased in the blood serum until 24 hours after 0.1, 0.25, 0.5, 2 and 4Gy irradiation and its activities returned normal condition after 72 hours of post-irradiation. Creatine kinase activities increased in the blood serum until 72 hours after 2 and 4Gy irradiation but any significant activity changes were not detected after 0.1, 0.25Gy irradiation. 2) Malate dehydrogenase activities did not reveal available changes after 0.1, 0.25, 0.5 Gy irradiation and lactate dehynrogenase activities decreased in the blood serum after 0.1, 0.25, 0.5 Gy irradiation.3) Glutamate oxaloacetate transaminase activity changes were detected in the blood serum after 0.1, 0.25, 0.5, 2, 4Gy(0.1Gy/min.) and GOT activities increased after 0.5, 1, 1.5, 2, 3, 5, 7Gy(0.5Gy/sec.). Any acid phosphatase activities were detected in the blood serum after 0.1, 0.25, 0.5, 2, 4Gy(0.1Gy/min.) and 0.5, 1, 1.5, 2, 3, 5, 7Gy(0.5 Gy/sec.) irradiation. Potentially some of these enzymes can be used as indicator protein for radiation injury. Futher investigation is needed to find better biochemical indicators utilizing recent know-ledge and techniques of biochemistry.