• Journal of Soil and Groundwater Environment
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• v.13 no.6
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• pp.62-71
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• 2008

Soil quality standards (SQS) are necessary to protect the human health and soil biota from the exposure to soil pollutants. The current SQS in Korea contain only sixteen substances, and it is scheduled to expand the number of substances. Chemical ranking and scoring (CRS) system is very effective to screen the priority chemicals for the future SQS in terms of their toxicity and exposure potential. In this study, several CRS systems were extensively compared to propose the assessment factors that required for the screening of soil pollutants The CRS systems considered in this study include the CHEMS-1 (Chemical Hazard Evaluation for Management Strategies), SCRAM (Scoring and Ranking Assessment Model), EURAM (European Union Risk Ranking Method), ARET (Accelerated Reduction/Elimination of Toxics), CRSKorea, and other systems. The additional assessment factors of CRS suitable for soil pollutants were suggested. We suggest soil adsorption factor as an appropriate factor of CRS system to consider chemical transport from soil to groundwater. Other factors such as soil emission rate and cases of accident of soil pollutants were included. These results were reflected to screen the priority chemicals in Korea, as a part of the project entitled ‘Setting the Priority of Soil Contaminants'.

• Journal of Food Hygiene and Safety
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• v.13 no.3
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• pp.201-205
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• 1998

In Korea, a small proportion of fishery products are contaminated with a considerable amount of potentially hazardous contaminants. So, there is generally a high risks to consumers. Inorganic contaminants with the greatest potential for toxicity are Sb, As, Cd, Pb, Hg, Se and the Sulfides. As appears to be much more variable than the others. This study was performed to assess the levels of the As in fisheries caught from the waters of the western coast of Korea. The samples included 26 kinds of fishes, 18 kinds of Mollusca, 3 kinds of Crustacea and 7 kinds of salted fishes. The Moisture content of molluscans was significantly higher than that of others (p<0.05). And the As contents of crustaceans were significantly higher than those of fishes, molluscans and salted fishes (p<0.05). The As content of Turban shell was 51.62 ppm, which was the highest among the samples. Also, the As contents of eel, cuttle fish and blue crab were found to be higher than in other fisheries. This variability offers a solution for the reduction of exposure to As through restricting the harvest of aquatic organism from the western coast of Korea.

• The Journal of Korean Medicine
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• v.27 no.2 s.66
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• pp.122-133
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• 2006

Objectives : The amyloid $\beta$-protein ($A\beta$) is the principal component of the senile plaques characteristic of Alzheimer's disease (AD) and elicits a toxic effect on neurons in vitro and in vivo. Many environmental factors including antioxidants and proteoglycans modify $A{\beta}toxicity$. In this study, we have investigated the protective effects of water- and organic solvent-extracts of Hemerocallis fulva root fractions pre-extracted with methanol on $A\beta$-induced oxidative cell death in cultured rat pheochromocytoma (PC12) cells. Methods : For this study, we used MTT reduction assay for detection of protective effects of water- and organic solvent-extracts of Hemerocallis fulva root fractions pre-extracted with methanol on $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells. We also used cell-based $\beta$-secretase assay system to investigate the inhibitory effect of water- and organic solvent-extracts of Hemerocallis fulva root on $\beta$-secretase activity. Results : We previously reported that methanol extracts of Hemerocallis fulva root strongly attenuated cytotoxicity induced by the three $A\beta$ fragments ($A{\beta}_{25-35},\;A{\beta}_{1-42}\;A{\beta}_{1-43}$) to both SK-N-MC and PC12 cells. In the present study, we found that butanol-, ethylacetate-, chloroform-, and water-extracts of Hemerocallis fulva root fractions pre-extracted with methanol had strong protective effects against $A{\beta}_{25-35}$-induced cytotoxicity to PC12 cells and inhibitory potency to $\beta$-secretase activity. Conclusion : These results suggest that butanol-, ethylacetate-, chloroform-, and water-extracts of Hemerocallis fulva root fractions pre-extracted with methanol may contain the protective component(s) against $A\beta$-induced cell death in PC12 cells as well as inhibitory component(s) to $\beta$-secretase activity.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.11
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• pp.1154-1160
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• 2008

Changes of zinc speciation and dehydrogenase activity in soil were studied before and after a field scale phytoextraction by Fagopyrum esculentum at a paddy soil near a closed zinc mine. The concentrations of zinc in paddy soil, in which Fagopyrum esculentum was planted, ranged from approximately 600 mg/Kg(high Zn soil) to 300 mg/Kg(moderate Zn soil). Despite of severe growth inhibition by Zn at the high Zn region, Fagopyrum esculentum accumulated phytoavailable fraction of Zn absorbed from the soil, and enhanced soil dehydrogenase activity (DHA) that had been inhibited by Zn toxicity. After the plant cultivation of 2 months, the concentrations of phytoavailable Zn in the rhizosphere soil at high and moderate Zn region has decreased 25% and 75%, respectively. The amount of Zn reduction in the rhizosphere soil corresponds to that accumulated in plants (recovery 92$\sim$107%), which implies Fagopyrum esculentum removed Zn from the soil. DHA was inversely correlated to the total Zn concentrations in soil. Before plant cultivation, the DHA in the high Zn soil was twice lower than that in the moderate Zn soil. More than 35% of DHA increase was observed in both soils after the application of phytoextraction with Fagopyrum esculentum.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.5
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• pp.558-568
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• 2011

Hazardous volatile organic compounds (HVOCs) have been increasingly getting concern in urban air chemistry due to photochemical smog as well as its toxicity or potential hazards. In this study, we investigated their concentrations and the properties in tunnel, urban roadside and residential area. As a result, among 36HVOCs measured in this study, BTEX (benzene, toluene, ethylbenzene, xylene) and dichlorodifluoromethane, 1,2,4-trimethylbenzene, trichlorofluoromethane were detected above the concentration of $1{\mu}g/m^3$ in every sampling site and the most abundant compound was toluene. The other compounds were detected at trace level or below the detection limit. In addition, we found that three CFCs (chlorofluorocarbons), such as CFC-12, CFC-11, CFC-113, were persistently detected because of the emission in the past. Toluene to benzene ratio (T/B) at tunnel and roadside were calculated to be 4.3~5.3 and at residential area 15.4, suggesting that the residential area had several emission sources other than car exhaust. The ratio of X/E (m,p-xylene to ethylbenzene) ratio was calculated to be 1.8~2.1 at tunnel, 1.7 at roadside and 1.2 at residential area, which means this ratio reflected well the relative photochemical reactivity between these compounds. Good correlation between m,p-xylene and ethylbenzene ($r^2$ > 0.85) were shown in every study sites. This indicated that correlation between $C_2$-alkylbenzenes were not severely affected by 3-way catalytic converter. In this study, it was demonstrated that the concentration of benzene was very low, compared with national air quality standard (annual average of $5{\mu}g/m^3$). Its concentration were $2.52{\mu}g/m^3$ in roadside and $1.34{\mu}g/m^3$ in residential area. We thought this was the result of persistent policy implementation including the reduction of benzene content in gasoline enforced on January 1, 2009.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.4
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• pp.373-379
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• 1994

Final biomass yields(cells/ml) and growth rates(divisions/day) of 4 clones of marine diatoms isolated from the Korean coastal waters were measured in media with 6 different levels of added cadmium concentrations. A neritic diatom, GS-12(Chaetoceros sp.), showed no growth at 0.1ppm cadmium, and its $IC_{50}$ for final biomass yield and growth rate was 0.03 and 0.02ppm, respectively. Two clones isolated from tidal pool, NC-37 and NC-29, showed enhanced tolerance to cadmium toxicity. Extremely high tolerance to cadmium addition was found in J-21 from a eutrophicated bay, with its high $IC_{50}$ for biomass yield(1.07ppm) and growth rate(1.92ppm). Present results implied a habitat related pattern of coastal diatom clones in the cadmium tolerances. Except GS-12, the other three diatom clones are considered to be highly tolerant to cadmium stresses.

• The Korea Journal of Herbology
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• v.30 no.4
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• pp.121-128
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• 2015

Objectives : Ojeok-san (OJS), an oriental herbal formula, has been used in Asian countries including Korea, China and Japan to treat the common cold and illnesses including fatigue and gastrointestinal disorders. The purpose of this study was to examine the anti-obesity effect and molecular mechanism of OJS, on adipogenesis in 3T3-L1 cells. Also, the effects of OJS in obese mice fed a high-fat diet on adiposity were examined.Methods : Preferentially, we analyzed the component of OJS and measured the stability of its component in OJS according to study periods using high performance liquid chromatography (HPLC). In vitro, 3T3-L1 cells were treated with OJS (50 to 200 μg/mL) during differentiation for 8 days. The accumulation of lipid droplets was determined by Oil Red O staining. The expressions of genes related to adipogenesis were measured by RT-PCR and Western blot analyses. For anti-obesty effect in vivo, we experimented for 8 weeks with four group (normal diet (CON), high-fat diet (HF), high-fat diet with OJS (HF+OJS) and high-fat diet with Bang-pung-tong-sung-san (HF+BTS) in comparison group HF+OJS).Results : OJS showed inhibitory activity on adipocyte differentiation at 3T3-L1 preadipocytes without affect cell toxicity as assessed by measuring fat accumulation and adipogenesis. In addition, OJS significantly reduced the expression levels of several adipocyte marker genes including proliferator activated receptor-γ(PPAR-γ) and CCAAT/enhancer-binding protein-α(C/EBP-α). Also OJS-administered mice showed significant inhibitory of body weights and abdominal adipose tissue weights.Conclusions : This study showed that traditional medicine OJS has an anti-obesity effect in vitro and in vivo. Thus, OJS could be developed as a supplement for reduction of body weight gain induced by an obesity.

• The Korean Journal of Malacology
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• v.29 no.2
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• pp.129-137
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• 2013

This study was conducted to find out the changes of survivorship, respiration and organ structure of Mactra veneriformis exposed to copper (Cu). Experimental period was four weeks. Experimental groups were composed of one control condition and three copper exposure conditions (0.025, 0.050 and 0.100 mg/L). The results of the study confirmed that copper induces reduction of survival rate and respiration rate and histopathology of organ structure of the bivalve. In the copper concentration of 0.100 mg/L, mortality was 100% after Cu exposure of 3 weeks. Respiration rate was observed exposure groups lower than control decline by 75%. Histological analysis of organ system illustrated expansion of hemolymph sinus, disappearance of epidermal layer and degeneration of connective tissue layer of the mantle. Also, histological degenerations as epithelial necrosis and hyperplasia of mucous cells are recognized in the gill and it was observed expansion of hemolymph sinus, disruption of epithelial layer, decrease of mucous cell and degeneration of connective tissue layer in the foot. In the digestive diverticulum, it was showed atrophy of basophilic cell and degeneration of epithelial cell in the digestive tubules, and as the concentration of copper increased the accumulation of lipofuscin increased.

• Journal of Oriental Neuropsychiatry
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• v.21 no.2
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• pp.125-140
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• 2010

Objectives : The purpose of this study is to examine from various angles the protective effect of Gastrodia elata Blume (GEB) against nerve cell death induced by $\beta$-amyloid by using the cell line SH-SY5Y, which is commonly utilized for toxicity testing in nerve cells, and to find out its mechanism of action. Methods : To begin with, as a result of assessing the rate of cell survival by employing MTT reduction assay, the treatment with $\beta$-amyloid at different concentrations caused cytotoxicity, which was inhibited by preprocessing GEB extract. In addition, after $\beta$-amyloid was processed with the cell SH-SY5Y, apoptosis progressed, which was reduced effectively by processing GEB extract. Results : When cytotoxicity was caused by using hydrogen peroxide, a representative ROS, in order to examine the antioxidant effect of GEB, its protective effect was also observed. Apart from ROS, reactive nitrogen species (RNS) are also known to play a crucial role in nerve cell death. The treatment with the NO donor SNAP increased the production of nitric oxide and the expression of iNOS, which was also inhibited by GEB extract. Meanwhile, as an attempt to find out the mechanism of action explaining the antioxidant effect, the intracellular antioxidant enzyme expressions were measured by RT-PCR, which showed that GEB extract increased the expressions of heme oxygenase-1, GAPDH and $\gamma$-glutamate cysteine ligase. Lastly, GEB extract had a protective effect against impaired memory induced by scopolamine in animal models (in vivo). Conclusions : These findings indicate that GEB has a protective effect against the death of cranial nerve cells, suggesting possibilities for the prevention and treatment of AD.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6129-6132
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• 2012

Objectives: To evaluate the feasibility and efficacy of simultaneous accelerated radiation therapy (SMART) and concurrent weekly paclitaxel in the treatment of locally advanced nasopharyngeal carcinoma. Methods: Forty-one patients with pathologically confirmed nasopharyngeal carcinoma were treated by SMART with concurrent weekly paclitaxel. Daily fraction doses of 2.5 Gy and 2.0 Gy were prescribed to the gross tumor volume (GTV) and clinical target volume (CTV) to a total dose of 70 Gy and 56 Gy, respectively. Paclitaxel of $45mg/m^2$ was administered concurrently with radiation therapy every week. Adjuvant chemotherapy was given four weeks after the completion of the radiotherapy (RT) if the tumor demonstrated only a partial response (PR). Results: All patients completed the radiotherapy (RT) course. Adjuvant chemotherapy was administered to 12 patients due to PR. The CR (complete remission) rate was 82.9% three months after RT. Thirty-nine (95.1%) patients completed the concurrent weekly chemotherapy with paclitaxel, and two patients skipped their sixth course. Seven patients had a 15% dosage reduction at the fifth and sixth course due to grade 3 mucositis. The median follow-up was 30 (range, 14-42) months. The three-year overall survival (OS), metastases-free survival (MFS), and local control rates were 77.0%, 64.4%, and 97.6%, respectively. No correlation between survival rate and T or N stage was observed. Grade 3 acute mucositis and xerostomia were present in 17.1% and 7.1%, respectively. Conclusion: SMART with concurrent weekly paclitaxel is a potentially effective and toxicity tolerable approach in the treatment of locally advanced NPC.