• Journal of Environmental Health Sciences
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• v.22 no.4
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• pp.91-101
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• 1996

Exposure indices are important tools which enable scientists to reliably predict and detect exposures to xenobiotics and resultant cell injury. Since the de novo synthesis of stress proteins can be detected early after exposure to some agents, analysis of toxicant-induced changes in gene expression, i.e. alterations in patterns of protein synthesis, may be useful to develop as biomarkers of exposure and toxicity. The acute and chronic effects of cadmium(Cd, $CdCl_2$ 20 mg/kg) on Wistar male rats were evaluated concerning cadmium contents, tissues enzyme activity, HSP expression. The results of the study were as follows: 1. Less cadmium was absorbed through the digestive tracts, but the ratio of contents in renal to hepatic cadmium was higher at 8 weeks after treatment. 2. ALT(alanine aminotransferase), AST(aspartate aminotransferase), glucose, BUN(blood urea nitrogen), creatinine, the key indices of the clinical changes in hepatic and renal function were significantly changed by the cadmium treatment after 1 week in liver, after 4 weeks in kidney. 3. Enhanced synthesis of 70 KDa relative molecular mass proteins were detected in 2 hours after cadmium exposure, with maximum activity occurring at 8~48 hours. Induction of $HSP_{70}$ was evident at proximal tubules and glomeruli in kidney. Testicular cells produced enough HSP to be detected normally. From the above results, it could be concluded that $HSP_{70}$ induction by the cadmium treatment was a rapid reaction to indicate the exposure of xenobiotics.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.657-661
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• 2011

The chlorinated dioxins and furans have attracted considerable scientific and public concern because of their environmental persistence and super-toxicity through the foodchain. Recent dioxin scandals in several military bases have also contributed to a higher awareness on the side of food consumers as well as foodwaste combustion. However, there is continuing uncertainty over the relative importance of different sources of dioxins and furans to the soil environment. In difference to those awareness there is a main influence of potential soil contamination on the dioxin contents in groundwater. It is, therefore, important to provide a sound scientific framework and basis by which to evaluate the significance of the presence of dioxin in soils. Consequently, we have to identify the characteristics and nature of dioxin released into the soil environment, especially in agricultural aspect.

• Toxicological Research
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• v.32 no.3
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• pp.231-237
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• 2016

Eryngium foetidum Linn. leaves (EF) are widely used in Thailand and many countries throughout Asia as a culinary seasoning and a traditional medicine. However, adverse effect of high dose consumption in long duration has not been evaluated. The aim of this study was to investigate chronic toxicity of EF in mice. Thirty-two ICR male mice were divided into 4 groups of 8 mice each. The mice were fed AIN-76 rodent diet, or AIN-76 rodent diet supplemented with ground freeze-dried EF at 0.8%, 1.6% and 3.2% that is equivalent to approximately 35, 73 and 155 times that of human consumption, respectively, at 97.5 percentile for a period of 24 weeks. At the end of experiment, the mice were euthanized and blood samples were collected for hematological and biochemical evaluations. Necropsy was performed while visceral organs such as lung, liver, kidneys, spleen etc. were collected, weighed and histopathologically examined. Blood urea nitrogen (BUN) results of mice in 1.6% and 3.2% EF diet groups were significantly higher than the BUN of control group. No significant difference was noted in other biochemical and hematological properties between the treatment groups and control; all results were within normal range. Histopathology of almost all visceral organs showed no significant changes. However, tubulonephrosis and chronic interstitial nephritis were observed in the groups treated with 1.6% and 3.2% EF diet. Body weight was reduced significantly at week 12 to week 20 when compared to the control group while relative kidney weights were significantly increased. In conclusion, the consumption of EF in diet at high doses illustrated the adverse effect on some biochemical parameters and histopathology in mice. Our findings suggested that EF daily consumption for 24 weeks, at higher doses than the 0.8% EF diet (35 times of human consumption), might cause adverse effect on kidney function in mice.

• Environmental Analysis Health and Toxicology
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• v.31
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• pp.11.1-11.6
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• 2016

Objectives A hazard assessment of di(2-ethylhexyl) phthalate (DEHP), a commonly used workplace chemical, was conducted in order to protect the occupational health of workers. A literature review, consisting of both domestic and international references, examined the chemical management system, working environment, level of exposure, and possible associated risks. This information may be utilized in the future to determine appropriate exposure levels in working environments. Methods Hazard assessment was performed using chemical hazard information obtained from international agencies, such as Organization for Economic Cooperation and Development-generated Screening Information Data Set and International Program on Chemical Safety. Information was obtained from surveys conducted by the Minister of Employment and Labor ("Survey on the work environment") and by the Ministry of Environment ("Survey on the circulation amount of chemicals"). Risk was determined according to exposure in workplaces and chemical hazard. Results In 229 workplaces over the country, 831 tons of DEHP have been used as plasticizers, insecticides, and ink solvent. Calculated 50% lethal dose values ranged from 14.2 to 50 g/kg, as determined via acute toxicity testing in rodents. Chronic carcinogenicity tests revealed cases of lung and liver degeneration, shrinkage of the testes, and liver cancer. The no-observed-adverse-effect level and the lowest-observed-adverse-effect level were determined to be 28.9 g/kg and 146.6 g/kg, respectively. The working environment assessment revealed the maximum exposure level to be $0.990mg/m^3$, as compared to the threshold exposure level of $5mg/m^3$. The relative risk of chronic toxicity and reproductive toxicity were 0.264 and 0.330, respectively, while the risk of carcinogenicity was 1.3, which is higher than the accepted safety value of one. Conclusions DEHP was identified as a carcinogen, and may be dangerous even at concentrations lower than the occupational exposure limit. Therefore, we suggest management of working environments, with exposure levels below $5mg/m^3$ and all workers utilizing local exhaust ventilation and respiratory protection when handling DEHP.

• Toxicological Research
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• v.16 no.4
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• pp.302-309
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• 2000

The purpose of this study is to investigate toxic effects of iso-butylalcohol (iBA) in Sprague-Dawley (SD) rats under the exposure of 6 hours a day, 5 days a week for 13 weeks by inhalation, and to evaluate the occupational safety of iBA in comparison with the permissible exposure level (PEL) stipulated by the Occupational Safety and Health Administration (OSHA). iBA did not induce any abnormal changes from the aspects of clinical signs, feed consumption, ophthalmic test, urinalysis, hematology and blood chemistry during and at the terminal of the inhalation toxicity tests. We did not find any abnormal findings in the gross and microscopic observations due to the inhalation of iBA. There was no alteration in relative organ weights by the inhalation of iBA. No observed adverse effect level (NOAEL) of iBA was considered to be more than 3,000 ppm in rats under the inhalation of 6 hours a day, 5 days a week for 13 weeks. Fifty ppm of iBA, the PEL regulated by OSHA, is too conservative for working places. As iBA showed no abnormal observations in all the experimental parameters at any concentration under this experimental condition, we suggest that 150 ppm is safe enough for the PEL of iBA in the working areas, even taking into onsideration that OSHA lowered the PEL to 50 ppm for fear of the probable risk of its skin irritation.

• Journal of Microbiology and Biotechnology
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• v.30 no.2
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• pp.172-177
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• 2020

Influenza viruses cause respiratory diseases in humans and animals with high morbidity and mortality rates. Conventional anti-influenza drugs are reported to exert side effects and newly emerging viral strains tend to develop resistance to these commonly used agents. Fritillaria thunbergii (FT) is traditionally used as an expectorant for controlling airway inflammatory disorders. Here, we evaluated the therapeutic effects of FT extracts against influenza virus type A (H1N1) infection in vitro, in ovo, and in vivo. In the post-treatment assay, FT extracts showed high CC50 (7,500 ㎍/ml), indicating low toxicity, and exerted moderate antiviral effects compared to oseltamivir (SI 50.6 vs. 222) in vitro. Antiviral activity tests in ovo revealed strong inhibitory effects of both FT extract and oseltamivir against H1N1 replication in embryonated eggs. Notably, at a treatment concentration of 150 mg/kg, only half the group administered oseltamivir survived whereas the FT group showed 100% survival, clearly demonstrating the low toxicity of FT extracts. Consistent with these findings, FT-administered mice showed a higher survival rate with lower body weight reduction relative to the oseltamivir group upon treatment 24 h after viral infection. Our collective results suggest that FT extracts exert antiviral effects against influenza H1N1 virus without inducing toxicity in vitro, in ovo or in vivo, thereby supporting the potential utility of FT extract as a novel candidate therapeutic drug or supplement against influenza.

• Nutritional Sciences
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• v.9 no.2
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• pp.68-73
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• 2006

This study was aimed at investigating hepatic toxicity and immunomodulating effects of defatted methanol extracts of two kinds of medicinal plants, Rubus coreanus Miq. and Atractylodes japonica Koidz. in mice. Defatted methanol extracts of fruits of Rubus coreanus Miq. and rhizome of Atractylodes japonica Koidz. were added at the level of 0.5% or 5%(w/w) to cholesterol-supplemented AIN-76 diet. Each diet was fed to 8 ICR male mice for 30 days. Weight gain and food efficiency ratio of the mice fed 5.0% extract of Rubus coreanus Miq. were significantly lower than those of the mice fed 0.5% extract Relative liver weight and activity of plasma alanine aminotransfernse were significantly increased only in the mice fed 5% extract of Atractylodes japonica Koidz. compared with the others. Splenocyte proliferation was not significantly different between the groups fed 0.5% or 5.0% extract of Rubus coreanus Miq. However, splenocyte proliferation was significantly decreased in the mice fed 5.0% extract of Atractylodes japonica Koidz. compared with that in the mice fed 0.5% Production of interleukin-2 by splenocytes from the mice fed 0.5% extract of Atractylodes japonica Miq. was significantly higher than the control value and it became lower with 5.0% dietary level. Secretion of $interferon-\gamma$ was not significantly different among groups. In conclusion, the defatted methanol extract of Atractylodes japonica Koidz. was likely to exert immunomodulating effect at the level of 0.5% but it may exert adverse effects on immune and liver functions at the level of 5.0%.

• Restorative Dentistry and Endodontics
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• v.14 no.1
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• pp.7-24
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• 1989

The purpose of the study was to evaluate the cytotoxic effects of polycarboxylate cements and zinc phosphate cements in vitro. Human fibroblasts were cultured in ${\alpha}$-MEM, and each cement was manually mixed and filled in glass ring cylinder (8${\times}$8mm in diameter, in height.) Cement filled cylinders were placed in the center of the dish (35mm in diameter) containing 3ml of ${\alpha}$-MEM. Millipore filters to simulate dentinal barrier were also placed between the cylinder and the dish, then stored in 5% $CO_2$ containing chamber for 1 and 2 weeks at the temperature of $36.6^{\circ}C$. The results of the experiments were analyzed by counting the cells in the period of one week and two weeks respectively, and were assessed by calculating the cell multiplication rate and the relative growth rate. The experimental groups and the control group were compared. The results of the study were summarized as follows. 1. Durelone brand of the polycarboxylate cements showed marked cytotoxicity after one week, but after two weeks the toxicity decreased remarkably. Poly-F brand exhibited moderate cytotoxicity after one week, but after two weeks the toxicity slightly decreased. HY-BOND brand was weakly cytotoxic after one week, but after two weeks the toxicity became significant. 2. The cytotoxicity of the zinc phosphate cements was negligible after one week, but after two weeks Lee Smith brand revealed considerable cytotoxicity. 3. In general, the zinc phosphate cements were less cytotoxic than the polycarboxylate cements.

• YAKHAK HOEJI
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• v.42 no.5
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• pp.534-539
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• 1998

Effect of recombinant human epidermal growth factor (rhEGF, DWP401) on fetal external, visceral and skeletal malformation during organogenesis was examined. Pregnant Sprauge-Daw ley rats were administered with 0.2, 1 and 5mg/kg/day subcutaneously on gestation day 6 through 16. Dams were sacrified at 20th day of gestation. Materal body weight, food consumption and clinical observation were not changed. Significant dose-dependent increase of relative and absolute liver weight were observed in the treatment group, whereas other organ weights were not changed. Placental weight of 1 and 5mg/kg/day group and number of resorption in 5mg/kg/day treatment group were significantly increased. External and visceral malformation of fetuses were not observed with treatment. However, skeletal variations(increase of asymmetry sternebrae, decrease of dumb-bell and asymmetry sternbrae at 5mg/kg/day, and fused stemebrae at 5mg/kg/day) were observed. These results showed that rhEGF (DWP401) may not have embryo and/or fetal developmental toxicity effect in rats.

• Journal of Veterinary Science
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• v.23 no.4
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• pp.56.1-56.17
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• 2022

Background: At the therapeutic doses, diclofenac sodium (DFS) has few toxic side effects on mammals. On the other hand, DFS exhibits potent toxicity against birds and the mechanisms remain ambiguous. Objectives: This paper was designed to probe the toxicity of DFS exposure on the hepatic proteome of broiler chickens. Methods: Twenty 30-day-old broiler chickens were randomized evenly into two groups (n = 10). DFS was administered orally at 10mg/kg body weight in group A, while the chickens in group B were perfused with saline as a control. Histopathological observations, serum biochemical examinations, and quantitative real-time polymerase chain reaction were performed to assess the liver injury induced by DFS. Proteomics analysis of the liver samples was conducted using isobaric tags for relative and absolute quantification (iTRAQ) technology. Results: Ultimately, 201 differentially expressed proteins (DEPs) were obtained, of which 47 were up regulated, and 154 were down regulated. The Gene Ontology classification and Kyoto Encyclopedia of Genes and Genomes pathway analysis were conducted to screen target DEPs associated with DFS hepatotoxicity. The regulatory relationships between DEPs and signaling pathways were embodied via a protein-protein interaction network. The results showed that the DEPs enriched in multiple pathways, which might be related to the hepatotoxicity of DFS, were "protein processing in endoplasmic reticulum," "retinol metabolism," and "glycine, serine, and threonine metabolism." Conclusions: The hepatotoxicity of DFS on broiler chickens might be achieved by inducing the apoptosis of hepatocytes and affecting the metabolism of retinol and purine. The present study could provide molecular insights into the hepatotoxicity of DFS on broiler chickens.