• Journal of Preventive Medicine and Public Health
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• v.29 no.3 s.54
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• pp.495-505
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• 1996

Effect or mercury chloride on the synthesis or $NO_2^-$ and ATP were observed in EMT-6 cells which were cultured with cytokines$(IL-1\alpha\;and\;IFN-\gamma)$ and various concentrations of mercury chloride from 0.05 to $0.8{\mu}M$. Viability of EMT-6 cells were observed above 90% in almost groups. There were not significant differences in the viability between mercury supplemented groups and control group. It suggests viability of EMT-6 cells were not influenced by these concentrations of mercury chloride. Results of the synthesis of nitrite showed significant time and group effect. There is a significant interaction effect between concentration of mercury chloride and culture time. The effect of various concentration of mercury chloride is not the same for all levels of culture time. There were significant differences in the synthesis of nitrite between mercury chloride supplemented groups and control group, and the synthesis of nitrite in EMT-6 cell by the supplement of mercury chloride was significantly decreased in a dose-dependent manner. Results of the synthesis of ATP showed a significant group effect, and the time main effect and the $Group{\times}Time$ interaction were also significant. There were significant differences in the synthesis of ATP between mercury chloride supplemented groups and control group, and the synthesis of ATP in EMT-6 cell by the supplement of mercury chloride was significantly decreased in a dose - dependent manner. These results suggest that the disorder of cell mediated immunity by mercury chloride could be related to the inhibition of nitric oxide synthesis which will be caused by the decreased synthesis of ATP.

• Radiation Oncology Journal
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• v.8 no.2
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• pp.207-212
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• 1990

To determine the correlation between the response to induction chemotherapy and subsequent radiotherapy we analyzed the clinical records of 60 patients with locally advanced carcinoma of the head and neck retrospectively who had completed a full course ($2\~3$ cycle) of induction chemotherapy and curative radiotherapy in Korea Cancer Center Hospital between 1986 and 1989. Chemotherapy was administeredd with CDDP+Bleomycin (BP) in 20, CDDP+5-FU (FP) in 37, and hybrid of BP and FP in three patients. Radiotherapy was giver conventionally with a dose of 65 to 75 Gy or more over seven to eight weeks according to the size of lesion. Response rates following induction chemotherapy were $80\%$ for the tumors and $879\%$ for the nodes whereas complete reponse rates were $12\%\;and\;13\%$, respectively. Six months after radiotherapy $67\%$ of the tumors and $77\%$ of the nodes achieved a complete response. Among the 48 tumor responders and the 31 nodal responders to chemotherapy,39 ($81\%$) and 28 ($90\%$), respectively, achieved complete response after radiotherapy. Thus, whether or not the tumor and node respond to induction chemotherapy was predictive of the response to subsequent radiotherapy (p<0.0005 in tumor, p<0.0001 in node). By reanalyzing according to disease subsets (i.e. primary site, T-stage, N-stage) this relationship was not observed at T1-T2 disease (p>0.3). Therefore the tumor or node's response to induction chemotherapy is a predictor for subsequent radiotherapy except in T1-T2 tumors, and complete response to radiotherapy can be expected despite the failure of induction chemotherapy in $T_1-T_2$ tumors.

• Radiation Oncology Journal
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• v.8 no.2
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• pp.189-198
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• 1990

Sixty-six patients with squamous cell carcinoma of the oropharynx were treated with radiation therapy and retrospectively analyzed to evaluate the treatment result in the Department of Therapeutic Radiology, Korea Cancer Center Hospital between January 1980 and December 1986. There were 42 patients with carcinoma of the tonsil including the fossa and pillar, 9 patients with carcinoma of the base of tongue,12 patients with carcinoma of the soft palate, and 3 patients with carcinoma of the posterior and lateral pharyngeal walls. Considering all oropharyngeal sites of involvement together, response rates for T1, T2, T3, and T4 were 80%, 77%, and 40%, respectively, with a overall response rate of 70%. The response rate for N1, N2, and N3 were 69%, 63%, and 40%, respectively, with the overall regional response rate of 70%. In lower T status, undifferentiated carcinoma and primary tumor arising from the soft palate, higher response rates were obtained. The S year overall and disease-free survival rate were 56%, 55%, respectively. A better prognosis was obtained in early T stage (T1+T2) (p<0.01) and in patients without tumor extension into adjacent structures in carcinomas arising from tonsillar area (p<0.01). Through this study we suggest that, in terms of anatomical and functional preservation, radiation therapy seems to be an effective method for the primary treatment of patients with oropharyngeal carcinoma.

• Journal of Food Hygiene and Safety
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• v.23 no.1
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• pp.6-14
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• 2008

Objective of this study was to investigate the residual levels of mercury (Hg) in soil for "Top-rice" area and its uptake into rice plant for making sure food safety as compared to "Top-rice" & common rice produced from 2005 to 2006. Hg was analyzed with the direct mercury analyzer (DMA 80, Milestone, Italy), which implements the US/EPA method 7473. The average concentration of Hg in paddy soil was 0.031 mg/kg, which was below at 1/25-1/65 fold of the threshold levels (concern level 4 mg/kg, action level 10 mg/kg) for soil contamination designated by "The Soil Environment Conservation Law" in Korea. The maximum residue level (MRLs) for Hg residue in the polished rice is not designated in Korea. Therefore, Hg contents in the polished rice of "Top-rice" brand and common rice were compared to other country's criteria. Hg contents in the polished rice of "Top-rice" brand was 0.0018 mg/kg, which was lower at 1/10-1/30 fold than the MRLs, 0.02 mg/kg of China criteria and 0.05 mg/kg of Taiwan criteria, respectively. Hg were 0.02788, 0.00896, 0.00182, 0.00189, 0.00166, 0.00452 and 0.00145 mg/kg in soil, rice straw, unhulled rice, rice hulls, brown rice, rice bran, and polished rice produced in 2006 "Top-rice" area, respectively. For the ratio of Hg as compared to Hg contents in soil, there were 0.321 of rice straw ${\gg}$ 0.162 of rice bran ${\gg}$ 0.068 of rice hulls > 0.065 of unhulled rice > 0.060 of brown rice> 0.052 of polished rice. And, the slope of Hg uptakes was steeped as following order; rice straw ${\gg}$ rice bran ${\gg}$ rice hulls > unhulled rice > brown rice > polished rice. It means that the more slope steeped was the more uptakes. For the distribution of Hg uptaken, there was 83.8% into rice straw, and 16.2% into unhulled rice, 2.8% into rice hulls, 12.4% into brown rice, 3.5% into rice bran and 9.7% into polished rice. Consequently, it was appeared that the Hg contamination in the polished rice should not be worried in Korea.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.1
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• pp.113-125
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• 2007

To know the differences in ionic compositions in rain and snow as well as snow influence on the chemical characteristics of winter precipitation, precipitation samples were collected by the wet-only automatic precipitation sample, in winter(November-February) in the Iksan located in the northwest of Chonbuk from 1995 to 2000. The samples were analyzed for concentrations of water-soluble ion species, in addition to pH and electrical conductivity. The mean pH of winter precipitation was 4.72. According to the type of winter precipitation, the mean pH of rain was 4.67 and lower than 5.05 in snow. The frequencies of pH below 5.0 in rain were about 73%, while those in snow were about 30%. Snow contained 3 times higher concentrations of sea salt ion components originated from seawater than did rain in winter, mainly $Cl^-,\;Na^+$, and $Mg^{2+}$. Neglecting sea salt ion components, $nss-SO_4^{2-}$ and $NO_3^-$ were important anions and $NH_4^+$ and $nss-Ca^{2+}$ were important cations in both of rain and snow. Concentrations of $nss-SO_4^{2-}$ was 1.3 times higher in rain than in snow, while those of $nss-Ca^{2+}$ and $NO_3^-$ were 1.5 and 1.3 times higher in snow, respectively. The mean equivalent concentration ratio of $nss-SO_4^{2-}/NO_3^-$ in winter precipitation were 2.4, which implied that the relative contribution of sulfuric and nitric acids to the precipitation acidity was 71% and 29%, respectively. The ratio in rain was 2.7 and higher than 1.5 in snow. These results suggest that the difference of $NO_3^-$ in rain and snow could be due to the more effective scavenging of $HNO_3$ vapor than particulate sulfate or nitrate by snow. The lower ratio in snow than rain is consistent with the measurement results of foreign other investigators and with scavenging theory of atmospheric aerosols. Although substantial $nss-SO_4^{2-}$ and $NO_3^-$ were observed in both of rain and snow, the corresponding presence of $NH_4^+,\;nss-Ca^{2+},\;nss-K^+$ suggested the significant neutralization of rain and snow. Differences in chemical composition of non-sea salt ions and neutralizing rapacity of $NH_4^+,\;nss-Ca^{2+}$, and $nss-K^+$ between rain and snow could explain the acidity difference of rain and snow. Snow affected that winter precipitation could be less acidic due to its higher neutralizing rapacity.

• Journal of Applied Biological Chemistry
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• v.55 no.4
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• pp.253-261
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• 2012

Dioxin contamination on agroproducts is one of the most important issue in food safety. Herein, we measured concentration of 17 dioxins polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) and 14 dioxin like-polychlorinated biphenyls (DL-PCBs) in the main grain (rice and barley) that were produced in Korea. The 36 rice samples were collected from rice processing complex at eight provinces, and the average concentrations of each province were ranged from 2.98 pg/g wet weight (w.w) to 4.98 pg/g w.w. as total PCDD/Fs and DL-PCBs. The seven barley samples were collected from Jeon-nam and Jeon-buk provinces, and their average total concentrations of PCDD/Fs and DL-PCBs were 3.00 pg/g w.w. and 3.24 pg/g w.w. respectively. The residual amounts and toxic equivalent (TEQ) of DL-PCBs in rice and barley were higher than PCDD/Fs. The average total TEQ of rice and barley were 0.0056 pg-TEQ/g and 0.0092 pg-TEQ/g on lower bound estimation respectively. Estimated daily intake of dioxins from rice and barley were calculated 1.03 pg-TEQ/day/person and 0.0534 pg-TEQ/day/person respectively. These were estimated 0.46% and 0.03% of Korean TDI based on 55 kg body weight.

• The Korean Journal of Pesticide Science
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• v.10 no.2
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• pp.99-106
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• 2006

Chlorothalonil and imidacloprid sprayed onto the green peppers were degraded more faster at outdoor than in greenhouse. These results were affected by dew and photodegration, considering no rain during the experimental period. Chlorothalonil, esfenvalerate and imidacloprid in green pepper, green twist pepper and sweet pepper did not show any residual pattern, because green peppers are one of the continuous harvesting crops and pesticides could not be sprayed homogeneously on them. When green peppers were pickled with soy sauce and green twist peppers were fried with vegetable oil, the amounts of pesticides such as alpha-cypermethrin, bifenthrin, chlorfenapyr, esfenvalerate and imidacloprid were diminished to the levels of about $30{\sim}71$ and $20{\sim}41%$, respectively. Esfenvalerate and imidacloprid could not be detected in 2 month-old hot pepper paste. The removal rates of pesticide residues in leaves of green peppers were about $22{\sim}37%$ by washing, about $74{\sim}95%$ by parboiling, and about $17{\sim}55%$ by drying after parboiling.

• The Korean Journal of Pesticide Science
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• v.6 no.4
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• pp.287-292
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• 2002

To establish effective and safe control method against Phytophthora root rot caused by Phytophthora capsici on tomato in hydroponic culture, three pesticides, oxadixyl copper hydroxide 8% WP, metalaxyl copper oxychloride 15% WP, and dimethomorph. dithianon 38% WP at 4 concentration levels were tested on potato dextrose agar medium inoculated with Phytophthora capsici. All pesticides inhibited mycelial growth, but two pesticides of them, metalaxyl copper oxychloride WP and dimethomorph. dithianon WP, were selected as effective pesticides for the efficacy test in a hydroponic culture. Forty days after transplanting of tomato seedlings, 4 ml of sporangia of P. capsici (about 25 sporangi/ml) per plot was inoculated around tomato plant root, and then 5 days after inoculation, the pesticides diluted at 5,000 times were drenched 1, 2 or 3 times per plot on the culture cube at 15 days interval. Fifteen days after drenching, tomato fruits and hydroponic culture solution were sampled for the analysis of pesticide residues. Dimethomorph was detected 0.001 and 0.003 mg/kg in tomato of the plots sprayed 2 and 3 times with dimethomorph dithianon WP of which detection levels were far below compared with 1.0 mg/kg of the Korean MRL of dimethomorph on tomato. Incidences of Phytophthora root rot were $30.5{\sim}50%$ in the plots drenched at 1 or 2 times with metalaxyl.copper oxychloride WP, and $16.7{\sim}25%$ in the plots treated with dimethomorph dithianon WP. However, there was no incidence of Phytophthora root rot in the plots treated at 3 times with both of pesticides, showing no phytotoxic effect. Based on the results, the drenching of these pesticides on the culture cube could be recommended as a very safe and effective control method for Phytophthora root rot in tomato.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.278-286
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• 2010

Veterinary antibiotics have been used to treat disease and to promote growth of livestock. However, the total amount of veterinary antibiotics in Korea was much greater than other developed countries, and there is a high potential to release residual of antibiotics to environment. Consequentially, released antibiotics into the environment produces antibiotic resistant bacteria and causes adverse effects on human health. The objective of this research was to monitor antibiotic concentration in the environment adjacent to facilities which compose chicken manure. Total of 10 antibiotics were selected based on the total amount of higher usage in Korea, and its residuals were measured from surface water, soil and sediment. The frequencies of detected antibiotics were ranged 31-92% from soil, 0-93% from water, and 33-93% from sediment. Generally, a higher frequency was observed in soil or sediment than water. Different ranges in concentration among 4 different antibiotic groups was found from not detected(N.D.) to 35.6 ${\mu}g/kg$ for soil, N.D. to 19.2 ${\mu}g/L$ for water and N.D. to 114.3 ${\mu}g/kg$ for sediment. Our findings suggest that solid phase such as soil and sediment is a critical component to be needed to conduct the environmental impact assessment of antibiotics.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.6
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• pp.631-638
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• 2010

The objective of this study was to evaluate the efficiency of zerovalent iron and basic oxygen furnace slag on arsenic stabilization in soils. For this, arsenic (V) contaminated soil and roxarsone contaminated soil were incubated after incorporation with zerovalent iron (ZVI) or basic oxygen furnace slage (BOFS) at four different levels (0%, 1%, 3%, and 5%) for 30 days and then the residual concentrations of arsenic were analysed following extraction with aqua reqia, 1N HCl and 0.01 M $CaCl_2$. The total concentration of arsenic was 2,285 mg/kg in the As(V) contaminated soil and 6.5 mg/kg in the roxarsone contaminated soil. 1 N HCl extractable arsenic concentration in the As(V) contaminated soil was initially 1,351 mg/kg and this was significantly declined by 713~1,034 mg/kg following incubation with ZVI while BOFS treatment showed no effect on the stabilization of inorganic arsenate except 5% treatment which showed around 100 mg/kg reduction in 1N HCl extractable arsenic. Similarly, in the roxarsone contaminated soil 1N HCl extractable concentration of arsenic was reduced from 3.13 mg/kg to 0.69 mg/kg with ZVI treatment increased from 1% to 5% while BOFS treatment did not lead to any statistically significant reduction. Available (0.01M $CaCl_2$ extractable) arsenic was initially 0.85 mg/kg in the As(V) contaminated soil and this declined by 0.79 mg/kg following incorporation with 5% ZVI, which accounted for more than 90% of the available As in the control. When As(V)-contaminated soil was treated with BOFS, the available arsenic was increased due to competing effect of the phosphate originated from BOFS with arsenate for the adsorption sites. For the roxarsone contaminated soil, the greater the treatment of ZVI or BOFS, the lower the available arsenic concentration although it was still higher than that of the control.