• Title/Summary/Keyword: Low Dose Radiation

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Inhibitory Effect of Hot-Water Extract of Paeonia japonica on Oxidative Stress and Identification of Its Active Components (백작약 열수추출물의 산화적 스트레스 억제효과 및 유효성분 동정)

  • Jeong, Ill-Yun;Lee, Joo-Sang;Oh, Heon;Jung, U-Hee;Park, Hae-Ran;Jo, Sung-Kee
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.5
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    • pp.739-744
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    • 2003
  • This study was carried out to investigate the antioxidative activity and to identify the active components of hot-water extract of Paeoniajaponica (PJ), which was a main ingredient of a herb mixture preparation recently established as a potent candidate of radioprotector in our laboratory. The water extract was fractionated with CHCl$_3$, EtOAc and n-BuOH. The extract and its fractions showed very low activity in hydroxyl radical scavenging test. In lipid peroxidation test, the extract, EtOAc and water fractions showed moderate inhibition with the ratio above 50%. In DPPH radical scavenging test, the extract, EtOAc and water fraction showed high activity with the ratio above 80%, especially. EtOAc fraction scavenged the radicals as much as synthetic antioxidant (BHA), even at low concentration. It is suggested that mai or partition for antioxidative activity of Paeonia japonica was EtOAc fraction. Subsequently, two active compounds (PJE021-1 and JE024-1) from EtOAc fraction were isolated by using MCI gel and silica gel column chromatography The two compounds inhibited remarkedly the $H_2O$$_2$-induced DNA damage in human peripheral blood lymphocytes, measured by single-cell gel electrophoresis (SCGE). PJE021-1 protected the cells to almost negative control level, dose-dependently. PJE024-1 exhibited a potent inhibition with the ratio of 71% at even low concentration (0.5 $\mu\textrm{g}$/$m\ell$). Finally, their chemical structures were identified as gallic acid (PJE021-1) and (+)-catechin (PJE024-1), respectively, on the basis of the speculation of spectral and physical data.

Hypothyroidism after Radiotherapy of Locally Advanced Head and Neck Cancer (국소 진행된 두경부암 환자의 방사선치료 후 갑상샘기능저하증)

  • Lee, Jeong-Eun;Kim, Jae-Chul;Yea, Ji-Woon;Park, In-Kyu
    • Radiation Oncology Journal
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    • v.28 no.2
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    • pp.64-70
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    • 2010
  • Purpose: The aim of the present study was to retrospectively evaluate the incidence of hypothyroidism in locally advanced head and neck cancer patients who received radiotherapy (RT) either with or without neck dissection. Materials and Methods: From January 2000 to December 2005, 115 patients with locally advanced head and neck cancer and who received definitive RT or postoperative RT including standard anterior low-neck field were recruited to be part of this study. Nineteen patients had undergone ipsilateral neck dissection, whereas, 18 patients underwent bilateral neck dissection, and 78 patients were received RT alone. Patients' ages ranged from 28 to 85 years (median, 59 years) and there were a total of 73 male and 42 female patients. The primary tumor sites were the oral cavity, oropharynx, hypopharynx, larynx, and other sites in 18, 40, 28, 22 and 7 patients, respectively. Radiation dose to the thyroid gland ranged from 44 Gy to 66 Gy with a median dose of 50 Gy. Follow-up time ranged from 2 to 91 months, with a median of 29 months. Results: The 1- and 3- year incidence of hypothyroidism was 28.7% (33 patients) and 33.0% (38 patients), respectively. The median time to detection of hypothyroidism was 8.5 months (range, 0 to 36 months). A univariate analysis revealed that neck node dissection was a risk factor for hypothyroidism (p=0.037). However, no factor was statistically significant from the results of a multivariate analysis. Conclusion: Patients treated for advanced head and neck cancer with radiotherapy with or without neck dissection will develop hypothyroidism. It is important to check the thyroid function periodically in these patientsespecially with the risk factor of neck node dissection.

Effect of Trace Elements in Alcohol Beverages on the Type of Radiation-induced Cell Death (인체 임파구세포에서 X-선 조사에 의한 세포사의 형태에 주정성분이 미치는 영향)

  • Sohn, Jong-Gi
    • Journal of Radiation Protection and Research
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    • v.35 no.2
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    • pp.49-56
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    • 2010
  • Developments of radioprotective agents are important issues for minimizing the troubles and the effective treatments in radiotherapy. But few agents are useful in clinical and practical fields. It was shown that trace elements in alcohol beverages might have radioprotective effect. In this study, the types of cell death of lymphocytes according to the commercial alcohol beverage was investigated. Normal healthy volunteers ingested distilled water, beer or soju containing $81.5mg{\cdot}dl^{-1}$ ethyl ahcohol, respectively. After 2 hours, their blood were sampled with their consents. Fraction of lymphocytes was isolated by density gradient method with Histopaque-1077 (Sigma) and irradiated with dose from 0.5 to 5 Gy. After 60 hour incubation, the cells were harvested and analysed by flow cytometry. Cell viability was decreased by dose dependent manner. Cell viability of beer group was reduced about 15% compared with control group. Apoptosis in soju group was reduced about 20% compared with control group. Apoptosis of beer and control groups are similar. Necrosis of soju group significantly increased about 35% compared with control group. Early apoptosis of beer group was increased compared with control group. Early apoptosis of soju group was decreased about 25% compared with control group. Late apoptosis of beer and control group was increased by dose dependent manner. Late apoptosis of soju group was increased about 20-30% compared with control group. Late apoptosis of soju was increased and the radioprotective effect of soju was minimal because late apoptosis induced the cell necrosis. In case of soju trace elements, total cell apoptosis was decreased about 20% and early cell apoptosis was remarkably low. In this case, mitotic cells death may be dominant mechanism. Therefore, trace elements in soju may not be effective radioprotective agents.

[ 137Cs] and 40K Activities of Foodstuffs Consumed in Jeju (제주지역에서 소비되는 식품 중 137Cs과 40K 방사능 농도)

  • Kang, Tae-Woo;Hong, Kyung-Ae;Park, Won-Pyo;U., Zang-Kual
    • Korean Journal of Environmental Agriculture
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    • v.23 no.1
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    • pp.52-58
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    • 2004
  • This work was conducted to provide the reference data of radioactivity in the foodstuffs at a radiological emergency situation in Jeju Island The sampled foodstuffs were agricultural (31), livestock (6), marine (12) and forest products (4), and processed foods (3) consumed by Jeju Islanders. $^{137}Cs$ and $^{40}K$ activities were determined by HPGe r-ray spectromety. The activity ranges of $^{137}Cs$ was ${\sim}650\;mBq/kg$ fresh in the agricultural products, ${\sim}131\;mBq/kg$. fresh in the livestock, ${\sim}834\;mBq/kg$ fresh in the forest, ${\sim}253\;mBq/kg$ fresh in the marine and $32.0{\sim}483\;mBq/kg$. fresh in the processed foods (tea). In case of $^{40}K$ the activity was $16.6{\sim}542\;Bq/kg$. fresh in the agricultural products, $39.1{\sim}294\;Bq/kg$ fresh in the livestock, $85.5{\sim}116\;Bq/kg$ fresh in the forest, $50.1{\sim}657\;Bq/kg$ fresh in the marine, and $33.6{\sim}1,065\;Bq/kg$ fresh in the processed foods (tea). The highest activity of $^{137}Cs$, 834mBq/kg fresh was observed in oak mushroom and $^{40}K$ 1,065 Bq/kg fresh in coffee. Annual effective doses of $^{137}Cs$ and $^{40}K$ by intake of foodstuffs per capita were the following order; agricultural products (66,543 nSv) > livestock products (19,311 nSv) > processed foods (6,648 nSv) > marine products (6,579 nSv) > forest products (860 nSv). Therefore, total annual effective dose was summed 99,941 nSv which is quite low level comparing to the annual effective dose by external exposure, 2,400,000 nSv. The data obtained in this study can be useful for monitoring whether the foodstuffs are contaminated or not at an emergency radiation accident, and showed that the foodstuffs consumed in Jeju are safe in terms of annual effective dose of $^{137}Cs$ and $^{40}K$

Intraoperative Radiation Therapy of locally Advanced Gastric Cancers - Case report - (국소진행 위암의 술중조사 2례)

  • Kim, Kyeung-Ae;Kim, Sung-Kyu;Shin, Sei-One;Kim, Myung-Se;Kim, Hong-Jin;Kwun, Koing-Bo;Kim, Hung-Dae
    • Journal of Yeungnam Medical Science
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    • v.5 no.1
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    • pp.153-158
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    • 1988
  • Stomach cancer is the most popular tumor in Korea but the prognosis following extensive surgery and chemotherapy has not improved for many years. Conventional external radiotherapy also has some limitation, namely, a cancerocidal dose can not be delivered to tumors because of low radiation tolerance of adjacent critical sensitive organs. In order to overcome these limitations of curative surgery and external radiotherapy, intraoperative radiotherapy was proposed in many centers and the results were excellent. We treated two cases of locally advanced gastric cancers with IORT by using NEC 18 MeV Linear Accelerator after standard subtotal resection of the stomach. After treatment, the patients are in good conditions so far, but in order to evaluate the effectiveness of IORT, a study will be performed on the survival rates between patients treated by IORT and those treated by surgery alone.

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The radioprotective effects of radices herbs (대표적 근류 생약의 방사선 방호효과)

  • Kim, Sung-ho;Oh, Heon;Kim, Se-ra;Jo, Sung-kee;Byun, Myung-woo;Kim, Kil-soo;Lee, Jong-hwan;Shin, Dong-ho
    • Korean Journal of Veterinary Research
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    • v.41 no.1
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    • pp.105-111
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    • 2001
  • We performed this study to determine the effect of Jiegeng(Platycodon grandiflorum), Danggui(Angelica sinensis), Gancao(Glycyrrhiza glabla), Chaihu(Bupleurum falcatnosa), Shoudehuang(Rehmannia glutinosa), Huangqi(Satragalus membranaceus), Muxiang(Saussurea lappa), Yuanzhi(Polygala tenuifolia), Rensen(Panax ginseng) and Baishaoyao(Paeonia lactiflolia), as Oriental radices herbs, on jejunal crypt survival, endogenous spleen colony formation and apoptosis in jejunal crypt cells of mice irradiated with high and low dose of ${\gamma}-radiation$. Jiegeng(p<0.005), Danggui(p<0.0005), Gancao(p<0.005), Chaihu(p<0.05), Muxiang(p<0.05), Rensen(p<0.005) and Baishaoyao(p<0.005) were effective in intestinal crypt survival. Danggui(p<0.05), Chaihu(p<0.05), Shoudehuang(p<0.05), Huangqi(p<0.05), Rensan(p<0.005) and Baishaoyao(p<0.05) increased the formation of endogenous spleen colony. The frequency of radiation induced apoptosis was also reduced by pretreatment with Chaihu(p<0.05), Muxiang(p<0.005), Yuanzhi(p<0.05), Rensan(p<0.05) and Baishaoyao(p<0.05). Although the mechanisms of this effect remain to be elucidated, these results indicated that Danggui, Chaihu, Muxiang, Rensan and Baishaiyao might be a useful radioprotector, especially since it is a relatively nontoxic natural product.

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Anti-oxidation and Anti-wrinkling Effects of Jeju Horse Leg Bone Hydrolysates

  • Kim, Dongwook;Kim, Hee-Jin;Chae, Hyun-Seok;Park, Nam-Gun;Kim, Young-Boong;Jang, Aera
    • Food Science of Animal Resources
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    • v.34 no.6
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    • pp.844-851
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    • 2014
  • This study focused on the anti-oxidative and collagenase- and elastase inhibition effects of low molecular weight peptides (LMP) from commercial Jeju horse leg bone hydrolysates (JHLB) on pancreatin, via enzymatic hydrolysis. Cell viability of dermal fibroblasts exposed to UVB radiation upon treatment with LMP from JHLB was evaluated. Determination of the antioxidant activity of various concentrations of LMP from JHLB were carried out by assessing 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azino-bis-3-ethybenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP), and oxygen radical absorbance capacity (ORAC). The DPPH radical scavenging activity of LMP from JHLB (20 mg/mL) was 92.21% and ABTS radical scavenging activity (15 mg/mL) was 99.50%. FRAP activity (30 mg/mL) was $364.72{\mu}M/TE$ and ORAC activity (1 mg/mL) was $101.85{\mu}M/TE$. The anti-wrinkle potential was assessed by evaluating the elastase- and collagenase inhibition potential of these LMP. We found that 200 mg/mL of LMP from JHLB inhibited elastase activity by 41.32%, and 100 mg/mL of LMP from JHLB inhibited collagenase activity by 91.32%. The cell viability of untreated HS68 human dermal fibroblasts was 45% when exposed to a UVB radiation dose of $100mJ/cm^2$. After 24 h of incubation with $500{\mu}g/mL$ LMP from JHLB, the cell viability increased to 60%. These results indicate that LMP from JHLB has potential utility as an anti-oxidant and anti-wrinkle agent in the food and cosmetic industry. Additional in vivo tests should be carried out to further characterize these potential benefits.

A Study on the dose distribution and the accuracy of the system for small fields of high energy x-rays (고에너지 X-선 소조사야의 선량분포 및 계측에 관한 연구)

  • 이호남;지광수;김재휴;지영훈
    • The Journal of Korean Society for Radiation Therapy
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    • v.7 no.1
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    • pp.32-44
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    • 1995
  • I. 제 목 고에너지 X-선 소조사야의 선량분포 및 계측에 관한 연구 II. 연구의 목적 및 중요성 최근 수술이 어려운 뇌종양등에 대한 방사선수술법(Radiosurgery)이 관심의 대상이 되고 있다. 방사선수술법은 크게 나누어 200여개의 Co-60이 장착된 장치(Gamma Knife)를 이용하는 방법과, X-선치료기를 이용하는 방법은 몇개의 보조기구를 설치하면 가능한 매우 경제적인 방법이다. 따라서 Microtron을 이용한 방사선수술의 기초자료확보를 위하여 소조사야에 대한 선량과 선량분포의 측정 및 계산을 실시하였다. III. 연구의 내용 및 범위 Microtron으로부터 조사되는 6MV, 10MV, 21MV X-선의 지름 3cm이하 소조사야에 대한 정확한 선량 및 선량분포 자료를 확보하기 위해, 가. Microtron치료기와 보조장치등에 대한 정밀도 계측 및 평가 나. 보조 Collimator의 적당한 크기와 재료의 선택 및 설계, 제작. 다. 에너지와 조사야 크기 각각에 대한 여러측정장치(Ion chamber, Diode detector, TLD 및 Film등)를 이용한 선량 및 선량분포 측정. 라. 측정값들의 비교, 검토 및 측정된 자료에 의한 선량 및 선량분포의 계산을 수행했다. IV. 연구결과 및 활용에 대한 건의 본 연구에서 얻은 결과는 다음과 같다. 가. Microtron치료기와 보조장치등의 정확도의 허용 오차범위내에서 잘 일치하였다. 나. 보조 collimater adpator는 총 길이 24cm로 하였으며 재질로는 두랄미늄을 사용하였고, 보조 collimator는 low melting alloy를 사용하였으며 소조사야 크기의 정확도는 0.5mm이내에서 매우 잘 일치 하였다. 다. 방사선 수술법의 에너지 선택에 중요한 요소중의 하나인 penumbra는 6MV X-선에서 가장 적게 나타났으며 라. 소조사면에 대한 깊이-선량 백분율곡선은 모든 에너지에서 조사면이 작아질수록 표면으로 이동하는 경향을 보였다. 이상의 결과로부터 방사선 수술을 시행할 경우 수십억원에 이르는 장비의 도입이나 새로운 시설 없이 Microtron에서 조사되는 고에너지 X-선을 이용할 수 있을 것으로 사료된다. 또한 새로 구입한 측정기나 보조 Collimator를 이용하여 소조사야에 대한 선량측정기술을 습득함으로써 일반적인 소조사야의 방사선치료나 회전치료등에 활용할 수 있다.

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Evaluation of DNA Damage Using Microwave Dielectric Absorption Spectroscopy

  • Hirayama, Makoto;Matuo, Youichirou;Sunagawa, Takeyoshi;Izumi, Yoshinobu
    • Journal of Radiation Protection and Research
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    • v.41 no.4
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    • pp.339-343
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    • 2016
  • Background: Evaluation of deoxyribonucleic acid (DNA)-strand break is important to elucidate the biological effect of ionizing radiations. The conventional methods for DNA-strand break evaluation have been achieved by Agarose gel electrophoresis and others using an electrical property of DNAs. Such kinds of DNA-strand break evaluation systems can estimate DNA-strand break, according to a molecular weight of DNAs. However, the conventional method needs pretreatment of the sample and a relatively long period for analysis. They do not have enough sensitivity to detect the strand break products in the low-dose region. Materials and Methods: The sample is water, methanol and plasmid DNA solution. The plasmid DNA pUC118 was multiplied by using Escherichia coli JM109 competent cells. The resonance frequency and Q-value were measured by means of microwave dielectric absorption spectroscopy. When a sample is located at a center of the electric field, resonance curve of the frequency that existed as a standing wave is disturbed. As a result, the perturbation effect to perform a resonance with different frequency is adopted. Results and Discussion: The resonance frequency shifted to higher frequency with an increase in a concentration of methanol as the model of the biological material, and the Q-value decreased. The absorption peak in microwave power spectrum of the double-strand break plasmid DNA shifted from the non-damaged plasmid DNA. Moreover, the sharpness of absorption peak changed resulting in change in Q-value. We confirmed that a resonance frequency shifted to higher frequency with an increase in concentration of the plasmid DNA. Conclusion: We developed a new technique for an evaluation of DNA damage. In this paper, we report the evaluation method of DNA damage using microwave dielectric absorption spectroscopy.

A Study on the Effect of Field Shaping on Dose Distribution of Electron Beams (전자선의 선량분포에 있어서 Field Shaping의 효과에 관한 연구)

  • Kang, Wee-Saing;Cho, Moon-June
    • Radiation Oncology Journal
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    • v.4 no.2
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    • pp.165-172
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    • 1986
  • In electron therapy, lead cutout or low-melting alloy block is used for shaping the field. Material for shaping electron field affects the output factor as wet 1 as the collimation system. The authors measured the output factors of electron beams for shaped fields from Clinac-18 using ionization chamber of Farmer type in polystyrene phantom. They analyzed the parameters that affect the output factors. The output factors of electron beams depend on the incident energy, collimation system and size of shaped field. For shaped field the variation of output factor for the field size (A/P) has appearence of a smooth curve for all energy and all applicator collimator combination. The output factors for open field deviate from the curves for shaped fields. An output factor for a given field can be calculated by equivalent field method such as A/P method, if a combination of applicator and collimator is fixed.

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