• Toxicological Research
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• v.26 no.3
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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.

• The Journal of the Korean dental association
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• v.10 no.3
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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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• v.39 no.1
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• pp.30-37
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• 2014

Recently High-Definition Reference Korean-Man (HDRK-Man) and High-Definition Reference Korean-Woman (HDRK-Woman) were constructed in Korea. The HDRK phantoms were designed to represent respectively reference Korean male and female to calculate effective doses for Korean by performing Monte Carlo dose calculation. However, the Monte Carlo dose calculation requires detailed knowledge on computational human phantoms and Monte Carlo simulation technique which regular researchers in radiation protection dosimetry and practicing health physicists do not have. Recently the UFPE (Federal University of Pernambuco) research group has developed, and opened to public, an online Monte Carlo dose calculation system called CALDOSE_X(www.caldose.org). By using the CALDOSE_X, one can easily perform Monte Carlo dose calculations. However, the CALDOSE_X used caucasian phantoms to calculate organ doses or effective doses which are limited for Korean. The present study developed an online reference Korean dose calculation system which can be used to calculate effective doses for Korean.

• Progress in Medical Physics
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• v.34 no.4
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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.

• Journal of radiological science and technology
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• v.41 no.2
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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.

• Progress in Medical Physics
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• v.19 no.3
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• pp.172-177
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• 2008

As a part of estimating quantitative radiation treatment doses, we produced a mathematical phantom based on the standard Korean male. Then, with the prostate as the source organ, we calculated the absorbed dose in the prostate and surrounding organs forecasted to occur during brachytherapy for prostate cancer. To simulate the procedure, we selected $^{25}I$ and $^{103}Pd$ useful in brachytherapy of the prostate as the radionucleids and made an assumption that 1 Ci of initial radioactivity is administered. As a result, we found that the prostate, as the source organ, indicated 101 Gy/Ci and 7.24 Gy/Ci, respectively, in case of $^{125}I$ and $^{103}Pd$. With the exception of the prostate, organs with high absorbed doses were found to be in the order of the penis and scrotum, sigmoid colon, testicles and the urinary bladder, which are relatively close to the prostate.

• Proceedings of the Korean Environmental Health Society Conference
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• 2003.06a
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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.

• The Korea Journal of Herbology
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• v.27 no.3
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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.

• Korean Journal of Environmental Biology
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• v.21 no.2
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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.

• Journal of radiological science and technology
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• v.11 no.2
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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.