79 2322-3243 Dr. Hossein Mozdarani 2053 Radiation Biology Effects of quercetin on ionizing radiation-induced cellular responses in HepG2 cells Jang J.Y. b Kang M.Y. c Lim Y.K. d Kim J.H. e Kim J.K. f b 1Korea Atomic Energy Research Institute, Advanced Radiation Technology institute, Jeongeup, Korea c Present address: Department of Earth Resources and Environmental Enineering, Hanyang University, Seoul, Korea d Department of Radiological Science, Gachon University, Incheon, Korea e Korea Atomic Energy Research Institute, Advanced Radiation Technology institute, Jeongeup, Korea f Korea Atomic Energy Research Institute, Advanced Radiation Technology institute, Jeongeup, Korea 1 7 2017 15 3 229 239 15 11 2017 15 11 2017 Background: Quercetin has been reported to modulate cell proliferation and apoptosis. The present study aimed at identifying whether treatment of ionizing radiation (IR) combined with quercetin induces apoptosis in HepG2 cells. Materials and Methods: HepG2 cells were plated at an appropriate density according to each experimental scale and irradiated with 1, 5 and 10 Gy gamma-rays from a 60Co source at room temperature. Cell viability, SOD and CAT were assessed by using commercial assay kits. Western blot analyses were done on apoptosis related proteins. The cells were treated with various concentrations of quercetin alone or in combination with IR.  Results: The cell viability was decreased in a concentration-dependent manner 24 h after treatment of quercetin. It was significantly lowered after the combined treatment of quercetin with IR than that of the cells treated with quercetin alone. Moreover, quercetin increased the expression of p53 levels in a dose-dependent manner. Combined treatment of quercetin with IR significantly increased the levels of pro-apoptotic proteins, cleaved caspase-3 and caspase-7, and Bax. Cell cycle analyses indicated a drastic increase in the Sub G1 population after quercetin treatment combined with IR. The activity of caspase-3 increased coincidently with apoptosis. The combined treatment of quercetin with IR decreased catalase and superoxide dismutase activities, as well. Conclusion: Quercetin made the radio-resistant HepG2 cells undergo apoptosis by activating p53. These results suggest that the combined treatment of quercetin with IR may provide an effective therapeutic strategy to improve the radiotherapy efficacy.    
2054 Radiation Biology Dosimetric investigation of high dose rate Ir-192 source with Monte Carlo method Acun H. g Bozkurt A. h Kemikler G. i g Harran University, Faculty of Medicine, Department of Biophysics, Osmanbey Campus, 63300 Sanliurfa, Turkey h Akdeniz University, Faculty of Engineering, Department of Biomedical Engineering, Antalya, Turkey i Istanbul University, Institute of Oncology, Department of Medical Physics, 34390 Capa, Istanbul, Turkey 1 7 2017 15 3 241 249 15 11 2017 15 11 2017 Background: This study aims to calculate the air-kerma strength (SK), the dose rate constant (∧) and the dose rate profiles of a Gammamed 12i Ir-192 source by using the Monte Carlo technique and to compare the dose rate values with those calculated by the Abacus HDR treatment planning system (TPS). Materials and Methods: Air-kerma strength (in units of U; 1 U= μGy m2 h-1) and the dose rate constant (∧) of a Gammamed 12i Ir-192 source were computed with the Monte Carlo-based code MCNP. For a single dwell position, profiles of dose rate per air kerma rate strength (in unit of U) along the x axis were obtained with MCNP and compared with data from the Abacus TPS at y=0, 1, and 2 cm. Results: The air-kerma strength and the dose rate constant of the source were calculated to 9.98×10-8 U and 1.106 cGy h-1 U-1, respectively. The maximum dose differences between MCNP and TPS along the x axis were found to be 1.3, 3.7 and 5.4% at distances more than 1 cm away from the source center for y= 0, 1 and 2 cm planes, respectively. Conclusion: The dose rate profiles calculated with MCNP and by the TPS show good agreement except for points located beyond the tip of the source.   2055 Radiation Biology Application of computed tomography and magnetic resonance imaging fusion images for delineating gross tumor volume in three-dimensional conformal radiotherapy of nasopharyngeal carcinoma Chen H. j Huang H. k Li G. l Huang D. m Huang S. n Wang Z. o j Department of Medical Oncology, the Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou 545005, China k Department of Medical Oncology, the Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou 545005, China l Department of Medical Oncology, the Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou 545005, China m Department of Medical Oncology, the Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou 545005, China n Department of Medical Oncology, the Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou 545005, China o Department of Medical Oncology, the Fourth Affiliated Hospital of Guangxi Medical University, Liuzhou 545005, China 1 7 2017 15 3 251 257 15 11 2017 15 11 2017 Background: To evaluate computed tomography (CT) and magnetic resonance imaging (MRI) fusion images for delineating gross tumor volume (GTV) in three-dimensional conformal radiotherapy (3D-CRT) of nasophanrygeal carcinoma (NPC), and compare treatment outcomes between CT- and CT+MRI-based targets. Materials and Methods: A total of 120 NPC patients treated with 3D-CRT were included, in which, 60 each were treated with CT-based and 60 with CT+MRI fusion targets. We explored the clinical application of CT+MRI fusion targets and compared the 1-, 3-, and 5-year survival and relapse rates between both targets. Results: The clinical characteristics and treatment factors were well balanced. The differences in public volume using CT alone in the CT+MRI (Group A) and the CT arm (Group B) were not significant (33.6±2.18 vs. 34.3±2.98, P > 0.05). The public volumes of GTV in the two arms were 49.48±2.46 cm3 and 33.6±2.18 cm3 respectively (P < 0.05). CT+MR fusion images did not influence the one-, three-, and 5-year survival rates (100% vs. 98.3%, 85.0% vs. 81.2%, and 73.3% vs. 68.3%, respectively). The three- and 5-year out-of-field progression was reduced in the CT+MRI arm. However, only the difference in 3-year out-of-field relapse rate was significant (3.3% vs. 13.3%; P < 0.05). The incidence of acute toxicities was similar between groups. Conclusion: The variability in GTV delineation in NPC was ascribed to intermodality and not interobserver variability. CT+MR fusion images likely reduced the 3-year out-of-field relapse rate.     2056 Radiation Biology Dosimetric comparison of TomoDirect and TomoHelical plans in post-mastectomy chest wall radiation therapy Teke F. p Doğan H.M. Kaya M.A. Gümüş M. p Dicle University, Medical School, Department of Radiation Oncology, Yenişehir 21280 Diyarbakır, Turkey Dicle University, Medical School, Department of Radiation Oncology, Yenişehir 21280 Diyarbakır, Turkey Dicle University, Medical School, Department of Radiation Oncology, Yenişehir 21280 Diyarbakır, Turkey Dicle University, Medical School, Department of Radiation Oncology, Yenişehir 21280 Diyarbakır, Turkey 1 7 2017 15 3 259 266 15 11 2017 15 11 2017 Background: The purpose of this study was to evaluate the characteristics of TomoDirect (TD) plans compared to conventional TomoHelical (TH) plans in chest wall irradiation in patients with breast cancer. Materials and Methods: TD and TH plans for only chest wall were retrospectively created for 30 patients previously treated with TH technique in our clinic. The beam angles were arranged to cover PTV chest wall and to minimize doses to OARs, ipsilateral lung and contralateral breast in TD plan. The prescribed dose was 50 Gy in 25 fractions. Results: The mean treatment times were similar in TH and TD (310.8 and 309 s, respectively, p> 0.05). There was no difference between the values of CI and HI of both plans (p>0.05). The values of Dmean, V5 and V20 of the ipsilateral lung in TD plan was significantly lower than that in TH plan for all 30 patients (p<0.001, p<0.001 and p=0.001, respectively).  V25 and V30 values of the heart were significantly lower in TH than those in TD plan in left-sided chest wall irradiation (p=0.006 and p<0.001, respectively). However, V5 values in TH was significantly higher than those in TD (p<0.001). In the right-sided, there was no difference between two plans for V25 and V30 values of heart (p>0.05). Conclusion: Both of TH and TD plans produce acceptable target dose coverage in chest wall RT. Considering the risk of low-dose radiation to the critical organs; TD mode improve dose distribution.     2057 Radiation Biology Standardization of whole breast radiotherapy is required for safe omission of axillary lymph node dissection in breast cancer patients Kong M. Shin D.O. Department of Radiation Oncology, Kyung Hee University Medical Center, Kyung Hee University School of Medicine, Seoul, Republic of Korea Department of Radiation Oncology, Kyung Hee University Medical Center, Kyung Hee University School of Medicine, Seoul, Republic of Korea 1 7 2017 15 3 267 273 15 11 2017 15 11 2017 Background: The purpose of this study was to assess the dose distribution and coverage of level Ⅰ-Ⅱ axillary lymph nodes during whole breast tangential field radiotherapy (RT) after breast-conserving surgery in patients with breast cancer. Materials and Methods: The level Ⅰ-Ⅱ axillary lymph node volumes were retrospectively contoured by a single radiation oncologist based on computed tomography simulation data from 44 patients who underwent breast-conserving surgery without axillary dissection and who received postoperative whole breast RT between January and December 2014. The dose distributions of the whole breast tangential RT fields were reassessed in relation to the axillary level Ⅰ and Ⅱ lymph node volumes. Results: : The average doses delivered to level I and I axillary lymph nodes were 49.4% (range, 14.2–94.6) and 30.8% (range, 2.6–71.5) of the prescribed radiation dose, respectively. The volumes receiving at least 95% of the prescribed radiation dose were 12.7% (range, 0–67.4%) for level I and 1.4% (range, 0–7.7%) for level II nodes. Compared to thin patients, the average doses delivered to axillary lymph node levels I and II were significantly higher in overweight patients. Conclusion: The radiation dose coverage of axillary lymph nodes by whole breast tangential RT varies greatly among patients. To safely omit axillary lymph node dissection from the treatment of clinically axillary lymph node negative T1-2 breast cancer patients with 1–2 positive sentinel lymph nodes, standardization and individualization of whole breast RT are necessary.     2058 Radiation Biology Monte carlo simulation of varian clinac iX 10 MV photon beam for small field dosimetry Yani S. Rhani M.F. Soh R.C.X. Haryanto F. Arif I. 1Department of Physics, Faculty of Mathematics and Natural Sciences, Institute Technology Bandung, Indonesia 2Department of Radiation Oncology, National University Cancer Institute Singapore, Singapore 3School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 4Department of Physics, Faculty of Mathematics and Natural Sciences, Institute Technology Bandung, Indonesia 5Department of Physics, Faculty of Mathematics and Natural Sciences, Institute Technology Bandung, Indonesia 1 7 2017 15 3 275 282 15 11 2017 15 11 2017 Background: The lack of lateral electronic disequilibrium (LED) becomes a main problem in small field. This factor affects the dose in target volume cannot predict correctly. In addition, utilization of high-energy linear accelerator (10 MV) can emit some unwanted particles (electron contamination). Therefore, the aim of this study was to characterize head linear accelerator (linac) Varian Clinac iX 10 MV photon beam for square small field size (1×1, 2×2, 3×3, 4×4 and 5×5 cm2) using Monte Carlo (MC) simulation. Materials and Methods: The commissioning process for this linac, has been conducted for field size 6×6, 10×10 and 20×20 cm2 by comparing the measurement and MC simulation data. Head linac simulation was performed with BEAMnrc and dose calculation with DOSXYZnrc. The phase space (phsp) data from BEAMnrc was analyzed using BEAMDP to get the particles information in scoring plane. Results and Discussion: The scatter angle of particles depends on the field size. This factor affects the penumbra width in water phantom. On the other hand, PDD data show that the depth of maximum dose and penumbra width in small field shifted correspond with the number of scatter particle. The difference of relative output factor between measurement and MC results were found less than 2%. However, the 2% difference was still acceptable in photon beam dosimetry. Conclusion: From this simulation, the electron contamination give contribution in surface dose of water phantom about 13.0581% and less than 1% for field size 10×10 cm2 and small field size, respectively.     2059 Radiation Biology Fewer beams and segments result in a shorter delivery time and a better quality intensity-modulated radiotherapy plan in gastric cancer Shen Y. Li X. Liang L. Zhao Y. Bai S. Xu F. Department of Abdominal Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, P.R. China Radiation Physics Center, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, P.R. China Department of Oncology, Sichuan Province People’s Hospital, Chengdu, Sichuan Province, P.R. China Department of Abdominal Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, P.R. China Radiation Physics Center, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, P.R. China Department of Abdominal Oncology, Cancer Center, West China Hospital, Sichuan University, Chengdu, Sichuan Province, P.R. China 1 7 2017 15 3 281 288 15 11 2017 15 11 2017 Background: This study evaluated whether IMRT using fewer beams and segments could reduce delivery time without compromising plan quality in gastric cancer adjuvant radiotherapy. Materials and Methods: Fifteen patients with advanced gastric cancer who underwent D2, R0 surgery were included in this study. IMRT plans for each patient were designed as 7 equal beams with 40 segments, 5 beams with 25 segments and 4 beams with 20 segments. The dosimetric parameters were compared for the planned target volume (PTV). The dose of normal organs at risk (OARs) was also assessed. The monitor units and treatment times of the different IMRT plans were calculated. Results: The 20-segment IMRT plan significantly reduced the PTV maximum dose compared to the 40-segment IMRT plan. The 20-segment IMRT plan improved left kidney and liver dose sparing in V20 and V30 as well as the 40-segment IMRT plan did and provided better protection for the V20 (13.86±7.78) of the right kidney, the V30 (9.25±4.04) of the left kidney, the D mean (19.68±2.47) of liver and D max (38.79±3.57) of the spinal cord. Irradiation times in the         20-segment and 25-segment plans decreased by 2.5 and 1.9 min, respectively, compared to the 40-segment IMRT plan. Conclusion: IMRT using fewer beams and segments reduced delivery time without compromising plan quality in gastric cancer adjuvant radiotherapy. Fewer segments IMRT plans lowered the monitor units and the treatment time.   2060 Radiation Biology Development and implementation of a Monte Carlo frame work for evaluation of patient specific out- of - field organ equivalent dose Atarod M. Shokrani P. Amouheidari A. Department of Medical Physics and Radiology, Shahrekord University of Medical Sciences, Shahrekord, Iran Department of Medical Physics, Isfahan University of Medical Sciences, Isfahan, Iran Radiotherapy Department, Milad Hospital, Isfahan, Iran 1 7 2017 15 3 289 294 15 11 2017 15 11 2017 Background: The aim of this study was to develop and implement a Monte Carlo framework for evaluation of patient specific out-of-field organ equivalent dose (OED). Materials and Methods: Dose calculations were performed using a Monte Carlo-based model of Oncor linac and tomographic phantoms. Monte Carlo simulations were performed using EGSnrc user codes. Dose measurements were performed using radiochromic films. Furthermore, the applicability of this framework was examined for a 3D conformal radiotherapy of breast. Results: Commissioning of the beam model was done by comparing the measured and calculated out-of-field dose values of several points in the physical and tomographic phantoms, respectively. The maximum percentage difference was 17%, which was smaller than 30% acceptance criteria for Monte Carlo modeling. The maximum statistical uncertainty in out-of-field dose calculation was 23%. Organ equivalent doses for out of field organs in 3D conformal radiotherapy of left breast varied from 2.4 cGy for right kidney to 134.6 cGy for the left humeral head. Conclusion: The framework developed in this research is a valuable tool for calculating peripheral dose and out-of field patient specific OEDs, the quantities needed for calculating risk of secondary cancer induction as a result of radiotherapy. This code can be used as a patient specific treatment plan optimization tool in order to select a treatment plan with the lowest risk of secondary cancer induction.     2061 Radiation Biology A comparison of contralateral breast dose due to breast cancer radiotherapy using two different treatment machines in a radiotherapy center Bouzarjomehri F. Rezaie Yazdi M. Department of Medical Physics, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran Department of Medical Physics, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran 1 7 2017 15 3 295 299 15 11 2017 15 11 2017 Background: The radiation dose received by contralateral breast (CLB) is one of the concerns of breast radiotherapy, because it may lead to the induction of secondary breast cancer. The aim of this study was to evaluate the CLB surface dose in the breast treatment in Yazd radiotherapy center. Materials and Methods: The surface dose of CLB was measured using TLD dosimetry in 50 cancer breast patients. The TLD chips were placed at four points on the each of CLBs. The patients were treated by 6MV photon beams of Oncor (physical wedge) and Compact (motorized wedge) LINAC. The TLD chips were placed on the surfaces of CLB during the medial and lateral tangent radiation fields in one of radiotherapy fractions. Results: The mean percent of prescription dose of the CLB surface doses on the point 1 in the two Linac (Oncor & Compact) were significantly different. The mean of CLB surface doses of point 1 in the physical and the motorized wedge techniques were 5.78 and 7.84 percent of prescription dose of breast cancer, respectively. The medial and lateral fields' contribution from 7.4% surface dose of CLB were 5.8% and 1.6%, respectively. Conclusion: In Shahid Ramezanzadeh radiotherapy center, the CLB surface dose due to breast cancer radiotherapy by the Compact machine (7.84 %) was significantly more than the allowable value (6% prescription dose). The CLB does due to the medial field beam was more than the lateral field.   2062 Radiation Biology Preliminary study on the properties of zinc oxide (ZnO) for alpha particles detection Shweikani R. Ismail A. Jerby B. Atomic Energy Commission of Syria, Protection and Safety Department, Damascus, P. O. Box 6091, Syria Atomic Energy Commission of Syria, Protection and Safety Department, Damascus, P. O. Box 6091, Syria Atomic Energy Commission of Syria, Protection and Safety Department, Damascus, P. O. Box 6091, Syria 1 7 2017 15 3 301 306 15 11 2017 15 11 2017 Background: : Due to the difficulties of locally obtaining ZnS(Ag), preliminary investigation of the radioluminescence characterization of Zinc oxide (ZnO) for alpha particle detection was performed. Materials and Methods: The scintillation properties of ZnO films were tested using alpha sources                     (Am-241). The correlations between ZnO scintillation responses and irradiation time and source activity were also verified and compared with the response of a ZnS(Ag) detector. Results: The obtained results showed that the response of ZnO was linear with the exposure time, and the uncertainty of the repeatability was less than 1%. In addition, ZnO was found to have good radiation resistance over a wide range of doses. Conclusion: The preliminary results may be indicative that the proposed ZnO detector could be considered as a promising detector for alpha particles.   2063 Radiation Biology Radio-epidemiological evaluation and remediation in water sources from two mines in South Africa Njinga R.L. Tshivhase V.M. Centre for Applied Radiation Science and Technology, North-West University, Mafikeng, South Africa Centre for Applied Radiation Science and Technology, North-West University, Mafikeng, South Africa 1 7 2017 15 3 307 315 15 11 2017 15 11 2017 Background: In this study, the health risk associated with three types of drinking waters (fissure, underground treated and surrounding waters) from two mines in South Africa were assessed. Materials and Methods: The measurement of the radionuclides concentration was carried out by liquid scintillation counter and alpha spectrometer. The estimated radiological risk pose to the people consuming the water types were evaluated based on the calculated radionuclide concentrations. Results: The value of the gross alpha was 1.15 ± 0.13 Bq/L and gross beta activity was 0.87 ± 0.11 Bq/L in the treated underground water. These values were several fold above the limit value of 1.0 Bq/L for gross alpha and 0.1 Bq/L for gross beta. For the fissure water, the gross alpha activity value was 0.56 ± 0.10 Bq/L which is less than the limit of 1.0 Bq/L and the gross beta activity was high with a value of 0.52 ± 0.11 Bq/L compared to the limit value of 0.1 Bq/L. The results around the Princess gold mine showed very high gross alpha and beta activity in the collected water samples studied. In general, the concentrations of the natural radionuclides were high especially 238U, 226Ra, 230Th, 235U, 234U and 210Po in all the water samples. Conclusion: The calculated chemical toxicity, cancer mortality/morbidity and hazards quotient with respect to 238U were very high. Hence, the waters within these vicinities are polluted with radionuclides and may posed serious health effect to the inhabitant.   2064 Radiation Biology Imbalances of the autonomic nervous system in people living in radioactive contaminated territories: radioactivity and vegetative imbalance Konstantinova E. Maslakova T. Zhivoderov A. Shalaumova Y. Varaksin A. Laboratory of Mathematical Modeling in Ecology and Medicine, Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, S. Kovalevskaya st. 20, 620990, Ekaterinburg, Russian Federation Laboratory of Mathematical Modeling in Ecology and Medicine, Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, S. Kovalevskaya st. 20, 620990, Ekaterinburg, Russian Federation Laboratory of Mathematical Modeling in Ecology and Medicine, Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, S. Kovalevskaya st. 20, 620990, Ekaterinburg, Russian Federation Laboratory of Mathematical Modeling in Ecology and Medicine, Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, S. Kovalevskaya st. 20, 620990, Ekaterinburg, Russian Federation Laboratory of Mathematical Modeling in Ecology and Medicine, Institute of Industrial Ecology of Ural Branch of Russian Academy of Sciences, S. Kovalevskaya st. 20, 620990, Ekaterinburg, Russian Federation 1 7 2017 15 3 317 320 15 11 2017 15 11 2017 Background: The Ural region is highlighted among other Russian regions for its unfavorable radiation situation and complexity of the overall environmental situation. The source of man-made radioactive contamination is the work of the "Mayak" Production Association. A significant radioactive contamination has happened as a result of several radiation incidents in the early period of the company activity and it has affected a territory total area of over 23,000 km2 in the Chelyabinsk, Kurgan and Sverdlovsk regions. Our primary aim is to compare the characteristics of Heart Rate Variability among residents of the Ural region, living in the territories with different levels of radioactive contamination. Materials and Methods: The segment of the population exposed to increased radiation exposure amounted to approximately 500 thousand people. We have distinguished three territories in the Urals region to perform a comparative study of environmental factors (the radioactive contamination) on human health. Two of these territories are case territories, which are exposed to environmental hazards, and one of them is the control. Data were collected from 1992 to 1995. Results: To assess the dependence of the state of adaptation abilities of the organism exposed to radiation contamination of the territory, we used the stress index. We determined the statistically significant influence of man-made radioactive contamination of the environment on the functional adaptation of the body. Conclusion: Our study showed the predominance of sympathetic regulation of heart rate, which indicates the tension of adaptation capabilities of the organism for the population living in radioactive contaminated areas. 2065 Radiation Biology Radioactivity level of soil around a coal-fired thermal power plant of northwest China Zhang X. School of Fine Arts, Shaanxi Normal University, Xi’an 710119, Shaanxi, China 1 7 2017 15 3 321 324 15 11 2017 15 11 2017 Background: The activity concentrations of natural radionuclides in soil around a coal-fired thermal power plant of northwest China were investigated for assessing the radioactivity level. Materials and Methods: Soil samples were collected around the coal-fired thermal power plant and their radioactivity levels were determined using gamma ray spectrometry. Radiation hazards were assessed by radium equivalent activity (Raeq), air absorbed dose rate (D) and annual effective dose equivalent (AEDE). ResultsThe activity concentrations of 226Ra, 232Th and 40K ranged from 24.7 to 89.8, 38.4 to 122.3 and 206.7 to 573.8 Bq kg-1 with an average of 49.7, 63.5 and 396.3 Bq kg-1, respectively. The mean Raeq value was less than the recommended limit, while the mean values of D and AEDE were slightly higher than the corresponding world average. Conclusion: The coal-fired thermal power plant enhanced the natural radiation of surrounding soil environment.