• Journal of Life Science
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• v.15 no.1 s.68
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• pp.1-8
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• 2005

The purpose of this study was to investigate the potential subacute toxicity of dimethyl disulfide by 3 weeks inhalation in F344 rats. The test article, dimethyl disulfide was exposed by inhalation to male and female rats at dose levels of 0, 5, 25, or 125 ppm/6 hrs/ day for 3 weeks. Five rats/ sex/ group were sacrificed on day 4 after the initiation of treatment, while 5 rats/ sex/ group were sacrificed at the end of treatment period. During the test period, clinical signs, mortality, body weights, food consumption, hematology, serum biochemistry, and gross findings were examined. Slight decreases in body weight gain were noted in both sexes of the highest dose group in a dose dependent manner but were only statistically different from the control animals in males of the group. A slight non-significant reduction in food consumption were also noted in the both sexes of the highest dose group. There were no adverse effects on mortality, clinical signs, hematology, serum biochemistry, and necropsy findings at any dose tested. Based on these results, it was concluded that the 3 weeks repeated dose of dimethyl disulfide by inhalation resulted in suppressed body weight gain and decreased food consumption at 125 ppm of both sexes. In the present experimental conditions, the target organ was not determined in rats. The no­observed-adverse-effect level (NOAEL) was considered to be 25 ppm/6 hrs/day for both sexes.

• Biomolecules & Therapeutics
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• v.26 no.5
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• pp.512-519
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• 2018

Phthalates widely used in the manufacture of plastics have deeply penetrated into our everyday lives. Recently, a concern over the toxicity of phthalates on thyroid, has been raised but in most of cases, the doses employed were unrealistically high. To investigate the effects of phthalates on thyroid, we investigated the effects of the repeated oral exposure to low to high doses (0.3, 3, 30 and 150 mg/kg) di-2-ethylhexylphthalate (DEHP) from weaning to maturity for 90 days in juvenile rats on the thyroid. The histological examination revealed that DEHP significantly induced hyperplasia in the thyroid from the doses of 30 mg/kg, which was confirmed with Ki67 staining. In line with this finding, increased mRNA expression of thyrotropin releasing hormone (Trh) was observed in the thyroid of female at 0.3 mg/kg and 150 mg/kg as determined by RNAseq analysis. Moreover, significantly increased expression of parathyroid hormone (Pth) in the female at 0.3 mg/kg, and thyroglobulin (Tg) and thyroid hormone responsive (Thrsp) in the male at 0.3 mg/kg were noted in the blood, of which changes were substantially attenuated at 150 m/kg, alluding the meaningful effects of low dose DEHP on the thyroid hormone regulation. Urinary excretion of mono-2-ethylhexyl-phthalate (MEHP), a major metabolite of DEHP was determined to be 4.10 and 12.26 ppb in male, 6.65 and 324 ppb in female at 0.3 and 30 mg/kg DEHP, respectively, which fell within reported human urine levels. Collectively, these results suggest a potential adverse effects of low dose phthalates on the thyroid.

• Korean Journal of Medicinal Crop Science
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• v.21 no.6
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• pp.474-485
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• 2013

Pharmacological studies and clinical practices have indicated that Radix Astragali, a dried root of Astragalus membranaceus possesses a lot of biological activities, including antioxidant, hepatoprotective, anti-diabetic, tonic, diuretic, antimicrobial, antiviral, and immunological activities. These biological activities approved by the modern pharmacological studies are mainly due to the constituents of Astragalus membranaceus including polysaccharides, saponins, flavonoids, amino acids, and trace elements. In resent, the main constituents in the root part showing a lot of biological activities has been isolated also from the aboveground parts such as leaves and sprouts in our laboratory. However, the safety evaluation for the aboveground parts of Astragalus membranaceus should be checked before expanding their application as one of food. In the study, a 90-day rat oral gavage study has been conducted with the extracts from Astragalus membranaceus-above-ground parts at doses of 1000, 3000, and 5000mg/kg/day. The following endpoints were evaluated: clinical observations, body weight, gross and microscopic pathology, clinical chemistry, and hematology. Based on the analysis of these endpoints, it was estimated that NOEL (no observed effect level) for male rats and NOAEL (no observed adverse effect level) for female rats are 5000mg/kg/day of the water-extracts from Astragalus membranaceus-aboveground parts.

• Korean Journal of Veterinary Research
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• v.45 no.1
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• pp.29-37
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• 2005

13-week orally repeated dose toxicity was investigated to ascertain the toxic effects of Aristolochiae radix in F344 rats at dose levels of 0, 1 (0.003 AA, aristolochic acid, mg/kg), 5 (0.014 AA mg/kg), 25 (0.068 AA mg/kg), 125 (0.34 AA mg/kg), and 500mg/kg (AA 1.36 mg/kg). No mortalities were found in any of the dose groups including vehicle control groups of both sexes during the study period. Hematologic and serum biochemical examinations revealed no changes related to the test item in any of the dose groups of both sexes. However, gross findings at necropsy implicated thickening of the stomach wall. In histopathological examinations, prominent findings related to the test item treatment were observed in the stomach and urinary bladder. There were squamous cell papilloma, squamous cell hyperplasia, ulceration and erosion observed in the non-glandular stomach. Squamouse cell hyperplasia was observed at dose levels of more than 125 mg/kg in both sexes and squamous cell papilloma was observed at dose level of 500 mg/kg in both sexes. The incidence and severity of these proliferating lesions including squamous cell hyperplasia and squamous cell papilloma increased with dose dependency. Transitional cell hyperplasia was also observed in the urinary bladder at dose levels of more than 25 mg/kg in both sexes and the incidence and severity of the lesion increased with dose dependency. In conclusion, the toxic changes related to the test item treatment were observed in the stomach and urinary bladder, and the no-observed-adverse-effect level (NOAEL) was estimated to be 5 mg/kg/day for both males and females in F344 rats.

• Korean Journal of Veterinary Research
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• v.44 no.4
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• pp.523-532
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• 2004

The present study was carried out to investigate the potential adverse effects of amitraz on pregnant dams after maternal exposure during the gestational days (GD) 1 through 19 in Sprague-Dawley rats. The test chemical was administered orally to pregnant rats at dose levels of 0, 3, 10, or 30 mg/kg/ day. During the test period, clinical signs, mortality, body weights, food consumption, serum biochemistry, gross findings, organ weights and reproductive findings on GD 20 were examined. In the 30 mg/kg group, an increase in the incidence of abnormal clinical signs and death, a suppression in the body weight gain, and a decrease in the food consumption were observed. A decrease in the liver weight and increases in the kidneys, adrenal glands and heart weights were also found. Serum biochemical investigations revealed increases in the aspartate aminotransferase (AST), total bilirubin, and chloride. In addition, an increase in the fetal death and decreases in the litter size and fetal body weight were seen at caesarean section. Inthe 10 mg/kg group, an increase in the incidence of abnormal clinical signs, decreases in the food consumption and liver weight, increases in the total bilirubin and chloride, and a decrease in the fetal body weight were observed. There were no adverse effects on clinical signs, mortality, body weights, food consumption, serum biochemistry, gross findings, organ weights and reproductive findings in the 3 mg/kg group. Based on the results, it was concluded that the 19-day repeated oral dose of amitraz to pregnant rats caused increases in the clinical signs, kidneys, adrenal glands and heart weights, AST, total bilirubin and chloride and decreases in the body weight gain, food consumption and liver weight at the dose levels of above 10 mg/kg/day. Under the present experimental conditions, the no-observed-adverse-effect level (NOAEL) of amitraz was considered to be 3 mg/kg/day.

• Biomolecules & Therapeutics
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• v.4 no.2
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• pp.127-137
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• 1996

This study was performed to investigate the toxicity of DA-125 in beagle dogs, an anthracycline antitumor antibiotic. The dogs were administered DA-125 i.v. at 0.0023, 0.0375, 0.15 and 0.6 mg/kg/day, 6 days/week for 26 weeks. At 0.6 mg/kg, all male and female dogs were either sacrificed moribundly or dead during the 26-week treatment. The dogs revealed inactivity, salivation, dark bloody discharge, swelling of the subcutaneous injection site, abscess, and ulceration in the abdominal wall and legs. At 0.15 mg/kg, anorexia, salivation, and swelling of the injection site were observed. The food consumption was decreased with a statistical significance at 6 and 12 weeks treatment in males of 7.6 mg/kg. At 0.0375, 0.15 and 0.6 mg/kg, body weights were decreased significantly in a dose-related fashion after 17 weeks treatment. Total white blood cell counts for male dogs at 0.6 mg/kg were lower than those of control dogs after 13 weeks treatment, which appeared mainly due to decreased neutrophils. At 0.15 mg/kg, testicular atrophy was found in all males by gross pathology and the testicular weights were significantly decreased when compared to those of control males. Microscopically, the testis showed moderate atrophy of the seminiferous tubules and marked decrease in number of spermatozoa in the epididymal tubules. At 0.6 mg/kg, petechia or echymotic hemorrhage was observed in gastrointestinal tract, heart, lungs, and other organs at the necropsy, Marked atrophy of thymus were observed in both males and females. In addition, severe testicular atrophy was noted in all males. Microscopically, gastrointestinal tract showed hemorrhage, epithelial denudation, hypermucus secretion, and atrophy of intestinal villi. Seminiferous tubules of the atrophic testis were lined with Sertoli cells only and devoid of germ cells. Severe oligospermia or aspermia was present in the epididymal tubules. Bone marrow showed marked depletion of hemopoietic cells. In addition, marked atrophy was found in the lymphoid tissue of gastrointestinal tract, various Iymph nodes, and thymus. Injection sites showed marked inflammatory response with necrosis, necrotizing vasculitis, thrombus formation, and ulceration in the skin. According to the present results, no observed effect level appeared to be 0.0375 mg/kg. At 0.15 mg/kg, testis was a target organ, while at 0.6 mg/kg hemopoietic tissue, gastrointestinal tract, and testis were considered to be target organs. At 0.6 mg/kg the test compound seems to inflict a damage on the blood vessels causing hemorrhage in the various organs and tissues.

• The Korea Journal of Herbology
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• v.36 no.5
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• pp.101-108
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• 2021

Objectives : A root of Dipsacus asperoides C. Y. Cheng et T. M. Ai (D. asperoides) has been traditionally used as a medicinal resource in several Asian countries, including Korean and traditional Chinese medicine that has been traditionally used for treating several medical conditions including pain, arthritis, and bone fractures in Korea. In the present study, we investigated potential subacute toxicities of D. asperoides extract. Methods : C57BL/6 mice (male, 7weeks) were randomly divided into 4 groups of 5 mice. Except for the control group, the mice were orally administrated D. asperoides extract at doses of 50, 150, or 450 mg/kg/day for 2 weeks. At the end of the treatment period, all mice were euthanized, and the following parameters were examined: mortality, body weight, clinical signs, gross findings, hematology, serum biochemistry, organ weight, and histopathology. Results : There were no abnormalities in mortality, clinical signs, body weight, gross findings, or organ weight after repeated administration of D. asperoides extract for 2 weeks, compared with the control group. In addition, there were no significant changes in hematological, serum biochemical, and histopathological parameters between the control group and D. asperoides extract administrated groups with doses of up to 450 mg/kg/day. Conclusion : In this study, D. asperoides extract showed no significant toxicities at a dose of up to 450 mg/kg/day in mice. Although we could not confirm the toxic dose of D. asperoides extract, it can be considered safe for further pharmacological use.

• The Journal of Korean Medicine
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• v.43 no.1
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• pp.18-32
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• 2022

Objectives: This study aimed to examine the safety, effects on proliferation of hair papilla cells, and anti-inflammatory and antioxidant mechanisms of Artemisia sieversiana Ehrh. ex Willd. (AS) extract. Methods: Safety tests through purity testing, acute toxicity tests, and repeated toxicity tests were performed using AS extract (ASE) which had been dried for over two years. Cell culture and proliferation tests were conducted; VEGF (vascular endothelial growth factor), bFGF (basic fibroblast growth factor), and EGF (epidermal growth factor) and protein expression analyses were performed for mechanistic evaluation; and inhibitory effects of ASE on the RNA expression of testosterone, 5𝛼-reductase, and aromatase was assessed. The anti-inflammatory and antioxidant efficacy of ASE was confirmed by measuring the levels of nitric oxide, inflammatory mediators (TNF-𝛼 and PGE2), inflammatory cytokines (IL-1𝛽, IL-6, and IL-8), and chemokine MCP-1. Results: The safety of ASE was confirmed. The mechanism of cell proliferation in human hair follicle dermal papilla cells involved the promotion of VEGF, bFGF, and EGF expression. ASE decreased mRNA expression of testosterone, 5𝛼-reductase, and aromatase-1 in a concentration-dependent manner. PGE2 and TNF-𝛼 production by inflammatory mediators was also significantly decreased in a concentration-dependent manner, and inflammatory cytokine and chemokine expression was inhibited. Conclusions: ASE is suggested to promote papillary cell growth at the cellular level, to suppress expression of various enzymes involved in hair cycle and cell death, and to inhibit hair loss through anti-androgen, anti-inflammatory, and antioxidant effects.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.361-371
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• 2000

It has been recently reported that 2-bromopropane (2-BP) induces male reproductive toxicity in both human and experimental animals. However, delayed effects of 2-BP on male reproductive system have not been investigated in detail. The present study was conducted to investigate the testicular toxicity of 2-BP and to determine the recovery of normal spermatogenesis in Sprague-Dawley rats. Male rats aged 5 weeks were administered 1,000mg/kg 2-BP by gavage daily for 4 weeks and sacrificed sequentially at 1, 2, 3, 4 and 12 weeks after initiation of 2-BP treatment. Testicular toxicity was evaluated qualitatively by histopathological examinations and quantitatively by reproductive organ weights, spermatid head count, and repopulation index. In the 2-BP treated rats, the body weights was significantly suppressed and the weights of testes and epididymides were also decreased in a time-dependent manner. On histopathological examination, spermatogonia in stages I-VI and preleptotene and leptotene spermatocytes in stages VII-IX were strongly depleted at 1 week of dosing. Spermatogonia were depleted extensively in all spermatogenic stages at 2 weeks. Continuing with the evolution of spermatogenic cycle, zygotene spermatocytes, pachytene spermatocytes, and round spermatids were sequentially depleted at 2, 3, and 4 weeks of dosing due to the depletion of their precursor cells. Vacuolization of Sertoli cells and spermatid retention were also observed at all time points, suggesting that 2-BP induced Sertoli cell dysfunction. At 12 weeks, after 8 weeks recovery, most of the tubules appeared severely atrophic and were lined by Sertoli cells only. Leydig cell hyperplasia in the interstitial tissue was also found. In addition, dramatic reductions in the number of spermatid heads and repopulation index were observed, indicating that 2-BP-induced testicular injury is irreversible. These results indicate that 4 weeks repeated-dose of 1,000mg/kg 2-BP results in a progressive germ cell loss due to the depletion of spermatogonia followed by long-term testicular atrophy in SD rats.

• Journal of Korean Academy of Nursing
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• v.26 no.2
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• pp.428-442
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• 1996

Stomatitis is a common toxicity associated with the administration of certain cancer chemotherapeutic agents used in the treatment of malignant tumors. It represents one of the most distressing side effects of cancer chemotherapy and can interfere with the patient's ability to eat, be the cause of much pain and discomfort, and require the use of potent analgesics. The situation also creates favorable conditions for local infection which may lead to septicemia. Several authors have identified the need to establish protocols for the control and treatment of the oral discomfort associated with oral mucositis as a result of chemotherapy. Thus this study attempted to development of oral care protocol for chemotherapy patients. The effects of the mouth care using sterile normal saline, nystatine solution on oral stomatitis were investigated in 30 patients on chemotherapy. The subsect were divided into three groups : control group : not gargling experimental group A : normal saline gargling (4 times a day) experimental group B : nystatine solution gargling(4 times a day) The Oral Assessment Guide (OAG) was used to assess oral status three times(once in the prechemotherapy period, on 5th, 10th day of post chemotherapy) Oral culture was used to assess oral infection on 5th day of postchemotherapy. Data was analyzed on SAS program which used repeated ANOVA, t-test, X/sup²test. The results are as follows : 1. The incidence of stomatitis was higher in the control group and experimental group A than in experimental group B.（X/sup²＝0.002 P＝0.001）. The grade of stomatitis(mean of total score) for patients in the experimental group B were significantly lower than in the experimental group A F＝1.96 P＝0.0024）. In incidence of tongue change, control group, experimental group B were significantly higher than experimental group B（F＝6.84 P＝0.0039）. In control group and experimental group A. oral infection due to pathogenic bacteria were identified. In conclusion, mouth care with nystatine solution four times a day could reduce the incidence of stomatitis and secondary oral infection due to stomatitis. Thus active mouth care protocol which used to nystatine solution gargling need to prevention of stomatitis in chemotherapy patients.