• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2334-2338
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• 2020

In recent years, 3D printing technology has received significant research attention. Additionally, 3D printing technology is being applied to study radiation dosimeters of various materials. In this study, a plastic scintillator for 3D printing was developed in a laboratory and used to manufacture a plastic scintillation dosimeter (PSD) with a shape identical to that of the ionization chamber PTW31010. The 16-mm beam of Gamma Knife® Perfexion™ was irradiated to derive the absorbed dose rates of the PSD and PTW31010; they were subsequently compared with the dose rates of the treatment plan. The differences in the dose rates of the Gamma Knife treatment plan and the absorbed dose rates of PTW31010 were within 0.87%. The difference between the dose rates of the Gamma Knife treatment plan and the absorbed dose rates of the PSD were within 4.1%. A linear fit of the absorbed dose rates of four shots involving different dose rates and irradiation angles yielded an adjusted R-square value exceeding 0.9999. A total of 10 repeated measurements were conducted for the same shot to confirm its reproducibility, with a relative error of 0.56%.

• Biomolecules & Therapeutics
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• v.2 no.3
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• pp.270-280
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• 1994

This study was conducted to evaluate the repeated dose toxicity of DA-3030, a recombinant human granulocyte colony stimulating factor(rhG-CSF), in rats. DA-3030 was administered intravenously once a day for 4 weeks to 20 males and 20 females per group at doses of 0(control), 115 and 1150 $\mu\textrm{g}$/kg, and to 15 males and 15 females per group at doses of 1.15 and 11.5$\mu\textrm{g}$/kg. After the administration period, 5 males and 5 females per group in the 0,115 and 1150 $\mu\textrm{g}$/kg groups were placed on withdrawal for 2 weeks. Through-out the study, all the rats survived. The administration of DA-3030 induced, a marked increase in the number of peripheral neutrophils, elevation of serum alkaline phosphatase activity, and splenomegaly in the rats of both sexes receiving 115 or 1150 $\mu\textrm{g}$/kg. Histopathologic examination revealed extramedullary granulopoiesis in spleen and liver, and increase in the number of activated macrophages in spleen in rats of both sexes in 115 and 115 $\mu\textrm{g}$/kg groups, and increased M/E ratio in 11.5, 115 and 1150$\mu\textrm{g}$/kg groups. Most of the changes produced by DA-3030 were thought to be attributable to exaggerated pharmacological effect of the drug, and subsided or disappeared after the recovery period. Under the present condition, no effect dose of DA-3030 is estimated at 1.15 $\mu\textrm{g}$/kg/day.

• Journal of the Korean Society of Food Culture
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• v.34 no.6
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• pp.801-809
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• 2019

Abeliophyllum distichum Nakai is a deciduous shrub of a flowering plant in Oleaceae. It is an important plant resource and consists of only one species in the entire world. A. distichum Nakai is well known an edible, medicinal herb in its habitat districts, but the toxicological evaluation for the safe use of its extract is still insufficient. The study characterized the toxicity of an Abeliophyllum distichum Nakai ethanol extract in Sprague-Dawley (SD) rats and determined the safe dosage levels in a 13 weeks toxicity study. Abeliophyllum distichum Nakai ethanol extract was orally administered once daily for 2 weeks at 0, 500, 1,000 and 2,000 mg/kg/day to male and female SD rats. while recording the clinical signs of toxicity, body weight, food intake/consumption, eye test and urine analysis. Only the total protein frequency in the urine of male SD rats (p<0.05), the right ovary of the 500 mg/kg group (p<0.01) and the right adrenal gland of the 1,000 mg/kg group (p<0.05) in the female rats showed statistically significant changes. But no toxic effects were noted from repeated-dose administration of the Abeliophyllum distichum Nakai ethanol extract in the SD rats during the observation period. The post-mortem examinations showed no test substance-mediated changes. The hematological analysis and clinical blood chemistry data demonstrated no toxic effects from repeated-dose administration of Abeliophyllum distichum Nakai ethanol extract in the SD rats during the observation period. Based on these results, this data suggests that a dose of 1,000 mg/kg/day is a highest treatment to administer when conducting a further 13 weeks toxicity study.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.23 no.1
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• pp.1-10
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• 2013

Objectives: The present study investigated the potential subacute toxicity of 1,4-dichlorobutane (1,4-DCB) by a 2-week repeated oral dose in male Sprague-Dawley rats. Materials and Methods: The test chemical was administered once daily by gavage to male rats at dose levels of 0, 74, 222, 667, and 2000 mg/kg/day for 2 weeks. All rats were sacrificed at the end of treatment period. During the test period, clinical signs, mortality, body weights, food and water consumption, urinalysis, hematology, serum biochemistry, gross findings, and organ weights were examined. Results: At 2000 mg/kg/day, treatment-related clinical signs, as evidenced by hypothermia, decreased locomotor activity, piloerection, lying on side, and prone position were observed. All the rats were found dead on test day 2. At 667 mg/kg/day, polyuria, suppressed body weight gain, food consumption, and spleen and thymus weights, and increased adrenal gland and liver weights were observed.Hematological and serum biochemical investigations revealed increases in the alanine aminotransferase, alkaline phosphataseand total bilirubinand decreases in the serum $Na^+$ level, white blood cell count and lymphocyte ratio. There were no treatment-related adverse effects in the 74 and 222 mg/kg/day groups. Conclusions: In the present experimental conditions, target organs were determined to be spleen, thymus,and liver. The no-observed-adverse-effect level was considered to be 222 mg/kg/day in male rats.

• Journal of Applied Biological Chemistry
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• v.62 no.2
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• pp.123-127
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• 2019

Medicinal herb in Asian countries has been traditionally used for a long time. However, the safety and adverse effect of medicinal herb have not been established yet. The aim of this study is to evaluate toxicity in the oral administration of Clausena excavata (C. excavata) in male ICR mice for 3 weeks and the noobserved adverse effect level (NOAEL). C. excavata has been used as a medicinal herb for the treatment of dermatopathy, malaria, abdominal pain, dysentery, and enteritis. C. excavata was orally administered daily for 21 days at a dose of 100, 250, 500, 1000, and 2000 mg/kg/day (MPK). There were no significant differences in mortalities, clinical signs, body weight changes, hematological, and serum biochemistry examination in all animals administrated with C. excavate. Consequently, these findings indicated that C. excavata did not affect the toxic effect in ICR mice and the NOAEL of C. excavata was considered as more than 2000 MPK.

• Herbal Formula Science
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• v.31 no.4
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• pp.327-339
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• 2023

Objectives : This study conducted a repeated dose 90-day oral toxicity test in order to up-cycling Schisandra fruit extract powder(SFEP) using discarded Schisandra chinensis by-products and evaluated the NOAEL of SFEP. Methods : SD-rats were orally administered SFEP at concentrations of 0, 62.5, 125, and 250 mg/kg once daily for 90 days. Body weights and clinical signs were observed during the administration period. After completion of the experiment, the experimental animals were autopsied to observe necropsy findings and organ weights changes, and hematological parameters and blood chemistry values were measured. Results : During the SFEP administration period, clinical signs such as salivation, wounds, and erosion were sporadically observed in 1 to 2 animals. In the SFEP 250 mg/kg administered group, weights of the liver and thyroid gland significantly increased compared to the control group, but no significant changes were observed in organ weights according to body weights. As a result of measuring hematological parameters and blood chemistry values, a decrease in RDW, T-BIL, and TBA, and an increase in TP, ALB, and Ca were observed due to SFEP administration. However, these changes following SFEP administration were accidental and not dose-dependent. Additionally, no correlation was found between gender and other parameters. Conclusions : Therefore, the NOAEL of SFEP was confirmed to be 250 mg/kg.

• Journal of Life Science
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• v.26 no.10
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• pp.1153-1162
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• 2016

Termitomyces albuminosus (Berk.) Heim is a well-known wild edible mushroom in the southern region of China. Novel cerebrosides, termed termitomycesphins, isolated from EtOH extract of T. albuminosus have shown significant neuritogenic activity. Neurotrophic factors have been targeted as potential therapeutic drugs for the treatment of neurodegenerative disorders. However, before expanding their applications to include food or therapeutic agents in Korea, a safety evaluation of T. albuminosus is needed. Herein, in a repeated-dose 90-day oral toxicity study, rats were exposed to a basal diet of powder ground from dried T. albuminosus at dose levels of 5%, 2.5%, 1.25%, and 0%. The following endpoints were evaluated: clinical observation, body weight, gross and microscopic pathology, clinical chemistry, and hematology. Significant dose-dependent increases in the weight of the left kidney were observed, possibly due to the test substance. Based on toxicity-decision criteria for minor compound-related changes (no observed adverse effect level [NOAEL] and no observed effect level [NOEL]), NOAEL was observed in male rats at a dose of 5% of dried T. albuminosus powder, and NOEl was observed in female rats at the same dose. The results point to the safety and potential use of T. albuminosus as a nontoxic neurotrophic factor.

• YAKHAK HOEJI
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• v.43 no.2
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• pp.180-197
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• 1999

Acute and subacute oral toxicity of $HELIKIT^{TM}$ ($^{13}C-urea$) were carried out in Sprague-Dawley rats of both sex. The toxicity of $HELIKIT^{TM}$ was compared with urea($^{12}C-urea$ which is used for control). In acute toxicity studies, we daily examined number of deaths, clinical signs, body weights and pathological examination for 14 days after single oral administration of HELIKIT or urea($^{12}C-urea$) at a dose of 5000 mg/kg. The subacute oral toxicity was investigated in Sprague-Dawley rats treated with $HELIKIT^{TM}$ at a dose of 40, 200 and 1,000 mg/kg/day or $^{12}C-urea$ at a dose of 1,000 mg/kg/day for 4 weeks. In acute toxicity studies, $HELIKIT^{TM}$ and urea did not show any toxic effect in rats and oral LD50 value was over 5,000 mg/kg rats. In subacute toxicity studies, no death occured and no drug-related changes were found in clinical observations; body weight, food consumption, opthalmoscopy. auditory test, urinalysis, hematology, blood chemistry, gross pathological examination or organ weight between $HELIKIT^{TM}$, urea and control groups. In histopathological examinations, the slight thickening of mucosa of the limiting ridge in the stomach was noted in the animals treated with $HELIKIT^{TM}$ at a dose of 1,000 mg/kg/day and also the changes in urea group at a dose of 1,000 mg/kg/day was found, but all of these changes in the changes in ures group at a dose of 1,000 mg/kg/days was found, but all of these changes in the stomach regressed after withdrawal of the test article for 2 weeks and reversibility of the effect was revealed. These results indicate that the non toxic dose level of $HELIKIT^{TM}$ was 1,000 mg/kg/day in the 4 weeks-repeated dose study, suggesting that the substitution of $^{13}C$ for carbon in urea molecule has no effect on the toxicity of urea and changes in stomach are reversible.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.301-301
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• 1994

〔$^3$H〕Ouabain binding parameters(K$\_$D/ and B$\_$max/,) in homogenates prepared fpom control rat ventricular strip and Langendorff preparations which were not previously exposed to ouabain were compared to those in homogenates from ventricular strip and Langendorff preparations that had been first exposed to a complete ouabain dose-response curve(10$\^$-7/M to 10$\^$-4/ M). In rat ventricular strips and Langendorff perfused rat heart preparations, cumulative dose-response cruves of ouabain revealed biphasic positive inotropic effects, a "low-dose" and a "high-dose" effect with ED$\_$50/ values of 0.5${\mu}$M and 35${\mu}$M ouabain, respectively- The "low-dose" effect in rat ventricular strips disappeared or was diminished significantly when the ouabain dose-response curve wag repeated after the washout of the effects of the first curve, whereas the maximal "high-dose" effect was identical in both exposures to oubain. However, there was no change in the "low-dose" effects in both sets of the Langendorff perfused hearts. The contractile activity of the pre-exposed strips did not indicate the presence of residual ouabain since their basal contractile force was decreased 10% compared to initial control. 〔$^3$H〕Ouabain binding parameters, K$\_$D/ and B$\_$max/, were not changed comparing homogenate of control ventricular strips with that of strips pre-exposed to ouabain. These results suggest that digitalis receptor desensitization in the rat ventricular strip may due to the change of post-receptor events induced by ouabain binding to a high affinity site(${\alpha}$$_2$ isoform).

• Journal of Pharmacopuncture
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• v.17 no.1
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• pp.51-58
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• 2014

Objectives: This study was performed to analyze single-dose intramuscular toxicity of Guseonwangdo-go glucose pharmacopuncture. Methods: Eighty six-week-old Sprague-Dawley rats were divided into two large groups of forty rats; Guseonwangdo-go glucose 5% and Guseonwangdo-go glucose 20% groups. Each group was sub-divided into four smaller groups of five males and five females, with the following dosages of pharmacopuncture being administered by intramuscular (IM) injection in each group: group 1 (G1, control group): 1.0 mL of normal saline solution, group 2 (G2, low-dose group): 0.1 mL, group 3 (G3, mid-dose group): 0.5 mL, and group 4 (G4, high-dose group): 1.0 mL. Results: No mortalities or clinical signs were observed in any group. Also, no significant changes in body weights or in hematological/biochemical analyses were observed between the control and the experimental groups during necropsy or histopathology. Conclusion: The above findings suggest that the lethal dose of Guseonwangdo-go glucose 5% and 20% pharmacopuncture administered via IM injection is more than 1.0 mL per animal in both male and female rats. Further studies on the repeated-dose toxicity of Guseonwangdo-go glucose should be conducted to yield more concrete data.