• Title/Summary/Keyword: Dose rate assessment

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Development and Assessment Individual Maximum Permissible Dose Method of I-131 Therapy in High Risk Patients with Differentiated Papillary Thyroid Cancer (물리학 선량법을 이용한 갑상선암의 개인별 최대안전용량 I-131 치료법 개발과 유용성 평가)

  • Kim, Jeong-Chul;Yoon, Jung-Han;Bom, Hee-Seung;JaeGal, Young-Jong;Song, Ho-Chun;Min, Jung-Joon;Jeong, Heong;Kim, Seong-Min;Heo, Young-Jun;Li, Ming-Hao;Park, Young-Kyu;Chung, June-Key
    • The Korean Journal of Nuclear Medicine
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    • v.37 no.2
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    • pp.110-119
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    • 2003
  • Purpose: Radioiodine (I-131) therapy is an effective modality to reduce both recurrence and mortality rates in differentiated thyroid cancer. Whether higher doses shows higher therapeutic responses was still debatable. The purpose of this study was to validate curve-fitting (CF) method measuring maximum permissible dose (MPD) by a biological dosimetry using metaphase analysis of peripheral blood lymphocytes. Materials and Methods: Therapeutic effects of MPD was evaluated in 58 patients (49 females and 9 males, mean age $50{\pm}11$ years) of papillary thyroid cancer. Among them 43 patients were treated with ${\Leq}7.4GBq$, while 15 patients with ${\geq}9.25GBq$. The former was defined as low-dose group, and the latter high-dose group. Therapeutic response was defined as complete response when complete disappearance of lesions on follow-up I-131 scan and undetectable serum thyroglobulin levels were found. Statistical comparison between groups were done using chi-square test. P value less than 0.05 was regarded as statistically significant. Results: MPD measured by CF method using tracer and therapeutic doses were $13.3{\pm}1.9\;and\;13.8{\pm}2.1GBq$, respectively (p=0.20). They showed a significant correlation (r=0.8, p<0.0001). Exposed doses to blood measured by CF and biological methods were $1.54{\pm}0.03\;and\;1.78{\pm}0.03Gy$ (p=0.01). They also showed a significant correlation (r=0.86, p=0.01). High-dose group showed a significantly higher rate of complete response (12/15, 80%) as compared to the low-dose group (22/43, 51.2%) (p=0.05). While occurrence of side effects was not different between two groups (40% vs. 30.2%, p=0.46). Conclusion: Measurement of MPD using CF method is reliable, and the high-dose I-131 therapy using MPD gains significantly higher therapeutic effects as compared with low-dose therapy.

Prevalence of Ruminal Lactic Acidosis and Clinical Assessments of Four Therapeutics in Goats of Bangladesh (방글라데시 염소에서 유산증의 분포 및 4가지 치료법의 임상적 적용)

  • Rahman, Md. Mahbubur;Islam, Mohammad Saiful;Adam, G.O.;Alam, Md. Rafiqul;You, Myung-Jo
    • Journal of Veterinary Clinics
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    • v.31 no.3
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    • pp.199-205
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    • 2014
  • Acidosis conditions either acute or chronic following ingestion of excessive amounts of readily fermented carbohydrate are great production problems for goat in Bangladesh. This study designed to investigate the prevalence of lactic acidosis and then response to different therapeutic agents. For this purpose, 1,128 goat were examined at outdoor District Veterinary Hospital, Faridpur, Bangladseh for treatment of which 40 goats were found positive for lactic acidosis showing 3.55% prevalence of disease. The highest occurrence found in female (4.64%) of over 3 years age (4.64%) in indigenous goat (2.7%). For therapeutic assessment the forty affected goats were divided into four groups A, B, C and D comprising of 10 animals each. Group A were given magnesium hydroxide 8% w/v at 1 g/kg body weight orally. In group B magnesium hydroxide 8% w/v at a dose as group A combination with 7.5% sodium bicarbonate at the rate of 0.9 ml/Kg body weight intravenously administered. Goat in group D were treated with mixture of ginger, nuxvomica, sodium carbonate, cobalt sulphate, dried ferrous sulphate and thiamin mononitrate at the rate of 1 g/kg body weight orally. Goat of group C treated with combination drugs of group A, B and D. The rectal temperature, pulse rate, respiration rate, was performed before and after treatment. It was found that the highest recovery in group C with an average period of $21{\pm}1.8$ hours. It was concluded that lactic acidosis is a common disease of goats and its severity can be effectively reduced by using combination drugs.

Glass Dissolution Rates From MCC-1 and Flow-Through Tests

  • Jeong, Seung-Young
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.257-258
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    • 2004
  • The dose from radionuclides released from high-level radioactive waste (HLW) glasses as they corrode must be taken into account when assessing the performance of a disposal system. In the performance assessment (PA) calculations conducted for the proposed Yucca Mountain, Nevada, disposal system, the release of radionuclides is conservatively assumed to occur at the same rate the glass matrix dissolves. A simple model was developed to calculate the glass dissolution rate of HLW glasses in these PA calculations [1]. For the PA calculations that were conducted for Site Recommendation, it was necessary to identify ranges of parameter values that bounded the dissolution rates of the wide range of HLW glass compositions that will be disposed. The values and ranges of the model parameters for the pH and temperature dependencies were extracted from the results of SPFT, static leach tests, and Soxhlet tests available in the literature. Static leach tests were conducted with a range of glass compositions to measure values for the glass composition parameter. The glass dissolution rate depends on temperature, pH, and the compositions of the glass and solution, The dissolution rate is calculated using Eq. 1: $rate{\;}={\;}k_{o}10^{(ph){\eta})}{\cdot}e^{(-Ea/RT)}{\cdot}(1-Q/K){\;}+{\;}k_{long}$ where $k_{0},\;{\eta}$ and Eaare the parameters for glass composition, pH, $\eta$ and temperature dependence, respectively, and R is the gas constant. The term (1-Q/K) is the affinity term, where Q is the ion activity product of the solution and K is the pseudo-equilibrium constant for the glass. Values of the parameters $k_{0},\;{\eta}\;and\;E_{a}$ are the parameters for glass composition, pH, and temperature dependence, respectively, and R is the gas constant. The term (1-Q/C) is the affinity term, where Q is the ion activity product of the solution and K is the pseudo-equilibrium constant for the glass. Values of the parameters $k_0$, and Ea are determined under test conditions where the value of Q is maintained near zero, so that the value of the affinity term remains near 1. The dissolution rate under conditions in which the value of the affinity term is near 1 is referred to as the forward rate. This is the highest dissolution rate that can occur at a particular pH and temperature. The value of the parameter K is determined from experiments in which the value of the ion activity product approaches the value of K. This results in a decrease in the value of the affinity term and the dissolution rate. The highly dilute solutions required to measure the forward rate and extract values for $k_0$, $\eta$, and Ea can be maintained by conducting dynamic tests in which the test solution is removed from the reaction cell and replaced with fresh solution. In the single-pass flow-through (PFT) test method, this is done by continuously pumping the test solution through the reaction cell. Alternatively, static tests can be conducted with sufficient solution volume that the solution concentrations of dissolved glass components do not increase significantly during the test. Both the SPFT and static tests can ve conducted for a wide range of pH values and temperatures. Both static and SPFt tests have short-comings. the SPFT test requires analysis of several solutions (typically 6-10) at each of several flow rates to determine the glass dissolution rate at each pH and temperature. As will be shown, the rate measured in an SPFt test depends on the solution flow rate. The solutions in static tests will eventually become concentrated enough to affect the dissolution rate. In both the SPFt and static test methods. a compromise is required between the need to minimize the effects of dissolved components on the dissolution rate and the need to attain solution concentrations that are high enough to analyze. In the paper, we compare the results of static leach tests and SPFT tests conducted with simple 5-component glass to confirm the equivalence of SPFT tests and static tests conducted with pH buffer solutions. Tests were conducted over the range pH values that are most relevant for waste glass disssolution in a disposal system. The glass and temperature used in the tests were selected to allow direct comparison with SPFT tests conducted previously. The ability to measure parameter values with more than one test method and an understanding of how the rate measured in each test is affected by various test parameters provides added confidence to the measured values. The dissolution rate of a simple 5-component glass was measured at pH values of 6.2, 8.3, and 9.6 and $70^{\circ}C$ using static tests and single-pass flow-through (SPFT) tests. Similar rates were measured with the two methods. However, the measured rates are about 10X higher than the rates measured previously for a glass having the same composition using an SPFT test method. Differences are attributed to effects of the solution flow rate on the glass dissolution reate and how the specific surface area of crushed glass is estimated. This comparison indicates the need to standardize the SPFT test procedure.

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Development of the Monte Carlo Simulation Radiation Dose Assessment Procedure for NORM added Consumer Adhere·Non-Adhere Product based on ICRP 103 (ICRP 103 권고기반의 밀착형·비밀착형 가공제품 사용으로 인한 몬테칼로 전산모사 피폭선량 평가체계 개발)

  • Go, Ho-Jung;Noh, Siwan;Lee, Jae-Ho;Yeom, Yeon-Soo;Lee, Jai-Ki
    • Journal of Radiation Protection and Research
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    • v.40 no.3
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    • pp.124-131
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    • 2015
  • Radiation exposure to humans can be caused by the gamma rays emitted from natural radioactive elements(such as uranium, thorium and potassium and any of their decay products) of Naturally Occurring Radioactive Materials(NORM) or Technologically Enhanced Naturally Occurring Radioactive Materials(TENORM) added consumer products. In this study, assume that activity of radioactive elements is $^{238}U$, $^{235}U$, $^{232}Th$ $1Bq{\cdot}g^{-1}$, $^{40}K$ $10Bq{\cdot}g^{-1}$ and the gamma rays emitted from these natural radioactive elements radioactive equilibrium state. In this study, reflected End-User circumstances and evaluated annual exposure dose for products based on ICRP reference voxel phantoms and ICRP Recommendation 103 using the Monte Carlo Method. The consumer products classified according to the adhere to the skin(bracelet, necklace, belt-wrist, belt-ankle, belt-knee, moxa stone) or not(gypsum board, anion wallpaper, anion paint), and Geometric Modeling was reflected in Republic of Korea "Residential Living Trend-distributions and Design Guidelines For Common Types of Household.", was designed the Room model($3m{\times}4m{\times}2.8m$, a closed room, conservatively) and the ICRP reference phantom's 3D segmentation and modeling. The end-user's usage time assume that "Development and Application of Korean Exposure Factors." or conservatively 24 hours; in case of unknown. In this study, the results of the effective dose were 0.00003 ~ 0.47636 mSv per year and were confirmed the meaning of necessary for geometric modeling to ICRP reference phantoms through the equivalent dose rate of belt products.

Scintigraphic Assessment of Hepatobiliary Functions in Healthy Miniature Pigs (건강한 미니돼지에서 간담도 기능의 핵의학적 평가)

  • Kim, Se-Eun;Shim, Kyung-Mi;Yoo, Kyeong-Hoon;Lee, Won-Guk;Choi, Seok-Hwa;Park, Soo-Hyun;Han, Ho-Jae;Kang, Seong-Soo
    • Journal of Veterinary Clinics
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    • v.24 no.4
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    • pp.593-596
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    • 2007
  • The purpose of this study is to investigate normal hepatobiliary functions in healthy miniature pigs. $^{99m}Tc-DISIDA$ hepatobiliary scintigraphy(HBS) was used for it. Five mCi dose of $^{99m}Tc-DISIDA$ was injected intravenously into 3 healthy adult miniature pigs, and dynamic images were obtained during 1 hour. $^{99m}Tc-DISIDA$ HBS in a miniature pig was evaluated for 6 variables. A cardiac washout occurred within 1 min in all miniature pigs and radioactivities in the gallbladder were not detected in two miniature pigs. Thus, the initial radioactivity and Tmax of the gallbladder were non-available to identify. Mean Tmax of liver was $8.67{\pm}2.08$ min and initial small intestinal radioactivity was seen at $9.67{\pm}2.52$ min after $^{99m}Tc-DISIDA$ injection. Mean hepatic washout time was not detected in 60 min dynamic images. Therefore, $^{99m}Tc-DISIDA$ HBS is the effective diagnostic method to evaluate the function of hepatocyte and bile flow rate. However, it was not a proper method to evaluate the function of gallbladder, which indicates that an additional study is needed to further specify the reasons for the absence of radioactivities in gallbladder of two miniature pigs.

Effects of Low-Dose Aspirin Therapy on Thermoregulation in Firefighters

  • McEntire, Serina J.;Reis, Steven E.;Suman, Oscar E.;Hostler, David
    • Safety and Health at Work
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    • v.6 no.3
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    • pp.256-262
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    • 2015
  • Background: Heart attack is the most common cause of line-of-duty death in the fire service. Daily aspirin therapy is a preventative measure used to reduce the morbidity of heart attacks but may decrease the ability to dissipate heat by reducing skin blood flow. Methods: In this double-blind, placebo-controlled, crossover study, firefighters were randomized to receive 14 days of therapy (81-mg aspirin or placebo) before performing treadmill exercise in thermal-protective clothing in a hot room [$38.8{\pm}2.1^{\circ}C$, $24.9{\pm}9.1%$ relative humidity (RH)]. Three weeks without therapy was provided before crossing to the other arm. Firefighters completed a baseline skin blood-flow assessment via laser Doppler flowmetry; skin was heated to $44^{\circ}C$ to achieve maximal cutaneous vasodilation. Skin blood flow was measured before and after exercise in a hot room, and at 0 minutes, 10 minutes, 20 minutes, and 30 minutes of recovery under temperature conditions ($25.3{\pm}1.2^{\circ}C$, $40.3{\pm}13.7%\;RH$). Platelet clotting time was assessed before drug administration, and before and after exercise. Results: Fifteen firefighters completed the study. Aspirin increased clotting time before and after exercise compared with placebo (p = 0.003). There were no differences in absolute skin blood flow between groups (p = 0.35). Following exercise, cutaneous vascular conductance (CVC) was $85{\pm}42%$ of maximum in the aspirin and $76{\pm}37%$ in the placebo groups. The percentage of maximal CVC did not differ by treatment before or after recovery. Neither maximal core body temperature nor heart rate responses to exercise differed between trials. Conclusion: There were no differences in skin blood flow during uncompensable heat stress following exercise after aspirin or placebo therapy.

Study on the Distribution of Fluorides in Plants and the Estimation of Ambient Concentration of Hydrogen Fluoride Around the Area of the Accidental Release of Hydrogen Fluoride in Gumi (구미 불산 누출사고 지점 주변 식물의 불소화합물 농도 분포 및 공기 중 불화수소 농도 추정에 관한 연구)

  • Gu, Seulgi;Choi, Inja;Kim, Won;Sun, Oknam;Kim, Shinbum;Lee, Yungeun
    • Journal of Environmental Health Sciences
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    • v.39 no.4
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    • pp.346-353
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    • 2013
  • Objectives: The goal of this study is to identify the distribution of the foliar fluorine content of vegetation surrounding the area where hydrofluoric acid was accidently released in Gumi, Gyeongsangbuk-do on September 27, 2012. In addition, it also aims to estimate the concentration of hydrogen fluoride in the air on the day of the accident. Methods: Samples of plant leaves were collected on October 7, 2012 within 1 km from the site where the accident occurred. These samples were analyzed for soluble fluorine ion with an ion selective electrode. The ambient concentration of hydrogen fluoride was calculated using the fluoride content in the plant via the dose-rate equation (${\Delta}F$=KCT). Results: The arithmetic and geometric means of the concentrations were 2158.2 and 1183.7mg F $kg^{-1}$ for leaves and, 2.4 and 1.1 ppm HF for the air, respectively. The highest concentration of hydrogen fluoride in the air was 14.7 ppm, which is higher than the maximum concentration reported by the government (1 ppm) and the exposure limit (ceiling, 3 ppm). The concentrations of both fluorine and hydrogen fluoride decreased with increasing distance from the accident site and showed a significant decrease outside of a 500m radius from the site (p <0.05). Conclusions: The area around the accident site was highly polluted with hydrogen fluoride according to the results of this study. Considering the persistency of hydrogen fluoride in the environment, long-term monitoring and environmental impact assessment should be pursued.

Resveratrol Exerts Differential Effects in Vitro and in Vivo against Ovarian Cancer Cells

  • Stakleff, Kimberly Sloan;Sloan, Tricia;Blanco, Denise;Marcanthony, Sharon;Booth, Tristan D.;Bishayee, Anupam
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1333-1340
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    • 2012
  • Epithelial ovarian cancer represents the most lethal gynecological cancer, and the high mortality rate makes this malignancy a major health concern. Poor prognosis results from an inability to detect ovarian cancers at an early, curable stage, as well as from the lack of an effective therapy. Thus, effective and novel strategies for prevention and treatment with non-toxic agents merit serious consideration. Resveratrol, obtained from grapes, berries, peanuts and red wine, has been shown to have a potent growth-inhibitory effect against various human cancer cells as well as in in vivo preclinical cancer models. The objective here was to evaluate potential antitumor effects of resveratrol in both in vitro and in vivo NuTu-19 ovarian cancer models. In vitro an invasion assay was performed. After 48 h, the numbers of viable cells that invaded the extracellular matrix layer were reduced by 94% with resveratrol in comparison to control. For the in vivo anti-tumor assessment, 10 rats were injected with NuTu-19 cells into the ovarian bursa. Thereafter, half were provided with a diet mixed with a dose of 100 mg resveratrol/kg body weight/day for 28 days. Following sacrifice, anticancer effects were assessed by histological evaluation of ovarian as well as surrounding tissues, and immunohistochemical detection of cell proliferation and apoptosis, but there were no observable differences between the control and resveratrol-treated groups for any of the biological endpoints. While resveratrol is effective in suppressing the in vitro cellular invasion of NuTu-19 ovarian cancer cells, these effects do not appear to impact on in vivo NuTu-19 ovarian cancers in rats.

Fertility-Preserving Treatments in Patients with Gynecological Cancers: Chinese Experience and Literature Review

  • Liu, Chun-Yan;Li, Hua-Jun;Lin, Hua;Ling, Bin
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.12
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    • pp.4839-4841
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    • 2015
  • We conducted a retrospectively reviewed of the literature published of patients underwent fertility-preserving treatments for cervical, endometrial and ovarian cancers using the WANFANG database in Chinese. A majority were retrospective studies and case reports. With cervical cancer, radical trachelectomy(RT) in combination with pelvic lymphadenectomy could preserve the fertility of patients with early stage IA1-IB1 cancers, Tumor size ${\leq}2cm$ should be emphasized as the indication of RT in considering of the higher recurrent rate in patients with tumor size >2cm. For endometrial cancers, there is much experience on it. Given accurate pretreatment assessment, hormonal therapy is feasible management option to preserve fertility in young patients with early stage lesions that limited to the endometrium and well differentiated. High dose progestin have been applied, oral medroxyprogesterone acetate (MPA), 250-500mg/day, megestrol acetate 160-480mg/day. Other therapies that have been used in a limited number of cases include GnRH analog, intrauterine devices (IUDS) containing progestogen, usually combination of these therapies. All patients should be followed up by ultrasound and/or MRI evaluation, and endometrial curettage at intervals of 3 months. With ovarian cancer, in China, fertilitypreserving surgery in patients with stage IA (grade G1) of epithelial ovarian tumor and patients with germ cell tumor and borderline ovarian tumor have been successfully performed.

Pharmacokinetic Characterization of Nano-emulsion Vitamin A, D and E (LaVita) in Rats

  • Lee, Young-Ju;Kwon, Min;Kim, Tae-Hwan;Kim, Kyun;Jeong, Sang-Hee;Chang, Hee-Ra
    • Korean Journal of Environmental Agriculture
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    • v.30 no.2
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    • pp.196-201
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    • 2011
  • BACKGROUND: Bioavailability enhancement by solubilization of lipophilic drugs in nano-emulsion has been reported and it may be useful in pharmaceutical and nutraceutical products. This study was performed to compare in vivo bioavailability of nano-emulsion formulation with that of the general product as control. METHODS AND RESULTS: The pharmacokinetics assessment of Vitamin A, D and E complex of nanoemulsion formulation (LaVita), in comparison to the general product, was performed in the male rat plasma by a single oral dose at 20 mL/kg body weight (n=3/group). For nano-emulsion formulation (LaVita), $C_{max}$ of vitamin A and E in plasma were much higher and the area under the curve (AUC) of vitamin A, D and E were 14-63% higher, and the half-life of vitamin E was 2-fold longer than the general product. According to statistical analysis, each $C_{max}$ of vitamin A, D & E was significantly higher (p<0.01, 0.05 and 0.01, respectively) than that of general product. Half-life of vitamin A was significantly higher (p<0.01) and AUC of vitamin A and D were also significantly higher than the general product. CONCLUSION(s): Considering significant increment of $C_{max}$ and AUC, LaVita made of nano-emulsion could be more effective the absorption rate and extent for bioavailability of vitamin A, D & E than those of general product.