• Toxicological Research
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• 제26권3호
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• pp.223-232
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• 2010

Artesunate, a semi-synthetic derivative of artemisinin, is used primarily as a treatment for malaria. Its effects on the central nervous system, general behavior, and cardiovascular, respiratory, and other organ systems were studied using mice, rats, guinea pigs, and dogs. Artesunate was administered orally to mice at doses of 125, 250, and 500 mg/kg and to rats and guinea pigs at 100, 200, and 400 mg/kg. In dogs, test drugs were administered orally in gelatin capsules at doses of 50, 100, and 150 mg/kg. Artesunate induced insignificant changes in general pharmacological studies, including general behavior, motor coordination, body temperature, analgesia, convulsion modulation, blood pressure, heart rate (HR), and electrocardiogram (ECG) in dogs in vivo; respiration in guinea pigs; and gut motility or direct effects on isolated guinea pig ileum, contractile responses, and renal function. On the other hand, artesunate decreased the HR and coronary flow rate (CFR) in the rat in vitro; however, the extent of the changes was small and they were not confirmed in in vivo studies in the dog. Artesunate increased hexobarbital-induced sleeping time in a dose-related manner. Artesunate induced dose-related decreases in the volume of gastric secretions and the total acidity of gastric contents, and induced increases in pH at a dose of 400 mg/kg. However, all of these changes were observed at doses much greater than clinical therapeutic doses (2.4 mg/kg in humans, when used as an anti-malarial). Thus, it can be concluded that artesunate is safe at clinical therapeutic doses.

• 대한치과의사협회지
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• 제10권3호
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• pp.159-162
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• 1972

Body weight and weight of submandibular gland of mice given subleathal doses of puromycin were studied after Pilocarpine. 1. Body weight showed a significant decrease during the firse 10 days after puromycin alone. 2. Injections of pilocarpine abolished the increase in glandular weight of the submandibular gland. 3. This was thought to indicate the possibility that the increase in organ weight might be due to the inability of the organs to release synthesized secretory Products.

• Journal of Radiation Protection and Research
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• 제39권1호
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• pp.30-37
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• 2014

최근 표준한국인 성인남녀 복셀 팬텀 한 쌍인 High-Definition Reference Korean-Man (HDRK-Man)과 High-Definition Reference Korean-Woman (HDRK-Woman)을 개발한 바 있다. HDRK-Man과 HDRK-Woman은 각각 한국인 성인 남성과 여성을 대표하므로 이들을 이용하면 한국인 고유의 유효선량을 계산할 수 있다. 이러한 한국인 고유의 유효선량을 계산하기 위해서는 표준한국인 팬텀을 이용한 몬테칼로 선량계산을 수행하여야 한다. 하지만 이러한 몬테칼로 선량계산은 전산인체모델에 대한 이해와 고도의 몬테칼로 전산모사 기술이 요구되기 때문에 몬테칼로 전산모사 경험이 적은 연구자들에게는 접근성이 용이하지 않다. 최근 UFPE (Federal University of Pernambuco) 연구팀에서는 몬테칼로 선량계산 온라인 시스템인 CALDOSE_X를 운영하고 있다. CALDOSE_X는 사용자가 온라인상에서 직접 입력한 선원조건에 따라 곧바로 몬테칼로 선량계산을 수행하고 계산된 결과를 제공해주는 온라인 서비스이다. 따라서 CALDOSE_X를 이용하면 몬테칼로 전산모사 경험 없이도 누구나 쉽게 원하는 선원조건에 대한 선량계산을 수행할 수 있다. 하지만 CALDOSE_X에서 제공하는 선량값은 서양인 전산팬텀을 이용하기 때문에, 이를 한국인 종사자에 대한 방사선 방호목적으로 사용하기에는 여전히 한계가 있다. 이에 본 연구에서는 온라인상에서 사용자가 입력한 선원조건에 따라 실시간으로 표준 한국인에 대한 유효선량을 계산할 수 있는 웹 기반 표준한국인 선량평가 시스템을 구축하였다.

• 한국의학물리학회지:의학물리
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• 제34권4호
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• pp.41-47
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• 2023

Purpose: This study aimed to dosimetrically compare the technique of three-dimensional conformal radiotherapy (3D CRT), which is a traditional prophylactic cranial irradiation method, and the intensity-modulated radiotherapy (IMRT) and volumetric modulated arc therapy (VMAT) techniques used in the last few decades with the dynamic conformal arc therapy (DCAT) technique. Methods: The 3D CRT, VMAT, IMRT, and DCAT plans were prepared with 25 Gy in 10 fractions in a Monaco planning system. The target volume and the critical organ doses were compared. A comparison of the body V₂, V₅, and V₁₀ doses, monitor unit (MU), and beam on-time values was also performed. Results: In planned target volume of the brain (PTV_Brain), the highest D99 dose value (P<0.001) and the most homogeneous (P=0.049) dose distribution according to the heterogeneity index were obtained using the VMAT technique. In contrast, the lowest values were obtained using the 3D CRT technique in the body V₂, V₅, and V₁₀ doses. The MU values were the lowest when DCAT (P=0.001) was used. These values were 0.34% (P=0.256) lower with the 3D CRT technique, 66% (P=0.001) lower with IMRT, and 72% (P=0.001) lower with VMAT. The beam on-time values were the lowest with the 3D CRT planning (P<0.001), 3.8% (P=0.008) lower than DCAT, 65% (P=0.001) lower than VMAT planning, and 76% (P=0.001) lower than IMRT planning. Conclusions: Without sacrificing the homogeneous dose distribution and the critical organ doses in IMRTs, three to four times less treatment time, less low-dose volume, less leakage radiation, and less radiation scattering could be achieved when the DCAT technique is used similar to conventional methods. In short, DCAT, which is applicable in small target volumes, can also be successfully planned in large target volumes, such as the whole-brain.

• 대한방사선기술학회지:방사선기술과학
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• 제41권2호
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• pp.141-148
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• 2018

This study examined the properties of photons and the dose distribution in a human body via a simulation where the total body irradiation(TBI) is performed on a pediatric anthropomorphic phantom and a child size water phantom. Based on this, we tried to find the optimal photon beam energy and material for beam spoiler. In this study, MCNPX (Ver. 2.5.0), a simulation program based on the Monte Carlo method, was used for the photon beam analysis and TBI simulation. Several different beam spoiler materials (plexiglass, copper, lead, aluminium) were used, and three different electron beam energies were used in the simulated accelerator to produce photon beams (6, 10, and 15 MeV). Moreover, both a water phantom for calculating the depth-dependent dosage and a pediatric anthropomorphic phantom for calculating the organ dosage were used. The homogeneity of photon beam was examined in different depths for the water phantom, which shows the 20%-40% difference for each material. Next, the org an doses on pediatric anthropomorphic phantom were examined, and the results showed that the average dose for each part of the body was skin 17.7 Gy, sexual gland 15.2 Gy, digestion 13.8 Gy, liver 11.8 Gy, kidney 9.2 Gy, lungs 6.2 Gy, and brain 4.6 Gy. Moreover, as for the organ doses according to materials, the highest dose was observed in lead while the lowest was observed in plexiglass. Plexiglass in current use is considered the most suitable material, and a 6 or 10 MV photon energy plan tailored to the patient condition is considered more suitable than a higher energy plan.

• 한국의학물리학회지:의학물리
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• 제19권3호
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• pp.172-177
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• 2008

정량적인 방사선치료 선량을 예측하기위한 일환으로 한국표준남성에 기초하여 수학적 모의피폭체를 제작하였다. 이후 전립선을 선원장기로 하여 전립선암 근접치료 시 발생할 것으로 예상되는 전립선 및 주변장기의 흡수선량을 산정하였다. 모의모사를 위하여 방사성핵종은 전립선 근접치료에 유용하게 사용되는 $^{25}I$ 및 $^{103}Pd$선정하였고, 초기 방사능을 1 Ci를 투여하는 것으로 가정하였다. 그 결과 선원장기인 전립선이 $^{125}I$ 및 $^{103}Pd$ 경우 각각 101 Gy/Ci와 7.24 Gy/Ci를 나타냈으며, 전립선을 제외하고 흡수선량이 높은 장기는 비교적 전립선과 인접되어 있는 장기 즉 음경과 음낭, S자결장, 정소, 방광순으로 나타났다.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2003년도 Challenges and Achievements in Environmental Health
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• pp.171-173
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• 2003

Bisphenol A (4,4'-isopropylidenediphenol, C$\_$15/H$\_$16/O$_2$) is the monomer used in the manufacture of polycarbonate. Polycarbonate, in turn, is used in a wide array of plastic products, with new applications continuously being developed. Also it has been used to produce epoxy resins and polycarbonate plastics for food container. This study was carried out to investigate the effects of bisphenol A on lactation period to dams and F1, Sprague-Dawley females were mated with on 2:1 ratio basis. Various doses of bisphenol A (0, 2, 20, 200, and 2,000 $\mu\textrm{g}$/kg) were daily administered to females for 21 days after parturition. Dams and offsprings were sacrificed at the time of weaning. The results were as follows, 2000 $\mu\textrm{g}$/kg of bisphenol A decreased the dams' body weight at post-partum 18 days and also 200 and 2000 $\mu\textrm{g}$/kg of bisphenol A decreased the body weight of neonates at the days of post-partum 21 days. Bisphenol A increased the relative weights of liver and spleen in male offsprings, depending on the doses. But female offsprings showed high relative organ weights of ovaries, and low relative organ weights of uterine in a some dose-response manners. High dose of bisphenol A induced low viability of neonates exposed during lactation period. The dams treated with bisphenol A showed prematured estrous stage. Bisphenol A was recovered about 21.2% average in serum of dams, and also in offsprings'. The results indicate that the bisphenol A induces estrous cycle during lactation period in dams, also reaches to the of offspring through breast milk. Thus bisphenol A exopsed to dams and neonates via lactation induces some estrogenic and toxic effects.

• 대한본초학회지
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• 제27권3호
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• pp.101-106
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• 2012

Objectives : To evaluate the toxicity of KOB03, polyherbal medicine for the treatment of allergic rhinitis, we performed the dose-range finding test of KOB03 by oral supplementation for 4 weeks in Sprague-Dawley rats. Methods : The water extract of KOB03 consisting of five different herbs was supplied from GLP company. KOB03 was supplemented by gavage at 0, 500, 2,500 and 5,000 mg/kg/day for 4-week consecutive days. We recorded the clinical signs of toxicity, body weight, organ weights, hematology, gross and histological changes in target organs of rats, and clinical chemistry analysis. Results : KOB03 at all doses was shown no mortality or abnormal clinical signs in rats during at the observation period. Furthermore, there was no difference in body weight and food-take consumption, organ weight, gross pathological findings, and urine analysis among the groups of rats treated with different doses of KOB03. The hematological analysis and clinical blood chemistry data were revealed no toxic effects from KOB03-supplemented rats. Conclusions : The results suggest that KOB03 is a wide margin of safety on dose-range toxicity in rats. The no observable adverse effect level (NOAEL) of the test, KOB03 in rats is no less than 5,000 mg/kg/day.

• 환경생물
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• 제21권2호
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• pp.208-215
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• 2003

Bisphenol A (4,4'-isopropylidenediphenol, $C^{15}H_{16}O_{2}$) is the monomer used in the manufacture of polycarbonate. Polycarbonate, in turn, is used in a wide array of plastic products, with new applications continuously being developed. Also it has been used to produce epoxy resins and polycarbonate plastics for food container. This study was carried out to investigate the effects of bisphenol A on lactation period to dams and F1. Sprague-Dawley females were mated with on 2 : 1 ratio basis. Various doses of bisphenol A (0, 2, 20, 200, and 2,000 ${\mu}g kg^{-1}$) were daily administered to females for 21 days after parturition. Dams and offsprings were sacrificed at the time of weaning. The results were as fellows, 2000 ${\mu}g \; kg^{-1}$ / of bisphenol A decreased the dams' body weight at post-partum 18 days and also 200 and 2,000 ${\mu}g \;kg^{-1}$ of bisphenol A decreased the body weight of neonates at the days of post-partum 21 days. Bisphenol A increased the relative weights of liver and spleen in male offsprings, depending on the doses. But female offsprings showed high relative organ weights of ovaries, and low relative organ weights of uterine in a some dose-response manners. High dose of bisphenol A induced low viability of neonates exposed during lactation period. The dams treated with bisphenol A showed prematured estrous stage. Bisphenol A was recovered about 21.2% average in serum of dams, and also in offsprings'. The results indicate that the bisphenol A induces estrous cycle during lactation period in dams, also reaches to the offspring through breast milk. Thus bisphenol A exopsed to dams and neonates via lactation induces some estrogenic and tonic effects.

• 대한방사선기술학회지:방사선기술과학
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• 제11권2호
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• pp.65-71
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• 1988

Radiation dose outside the radiotherapy treatment field can be significant and therefore is of clinical interest estimating organ dose. We have made measurements of dose at distances up to 70 cm from the central axis of $5{\times}5$, $10{\times}10$, $15{\times}15$, and $25{\times}25$ cm radiation fields of Co-60 ${\gamma}-ray$, at 5 cm depth in water. Contributions to the total secondary radiation dose from water scatter, machine (collimator) scatter and leakage radiation have been seperated. We have found that the component of dose from water scatter can be described by simple exponential function of distance from the central axis of the radiation field for all field sizes. Machine scatter contributes 20 to 60% of the total secondary dose depending on field size and distance from the field. Leakage radiation contributes very little dose, but becomes the dominant componant at distance beyond 40 cm from the central axis. Then, wedges can cause a factor 2 to 3 increase in dose at any point outside the field compared with the dose when no wedge is used. Adding blocks to a treatment field can cause an increase in dose at points outside the field, but the effect is much smaller than the effect of a wedge. From the results of these measurements, doses to selected organs outside the field for specified treatment geometries were estimated, and the potential for reducing these organ doses by additional shielding was assessed.