• Journal of Preventive Medicine and Public Health
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• v.28 no.1 s.49
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• pp.225-243
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• 1995

Benzidine Industry in Korea has started after Japan has banned its production in early 1970's, and it has been in operation in Korea for over 20 years. However, it is not known yet whether any bladder cancer has developed from benzidine exposure. This study was done to screen benzidine-exposed workers for bladder cancer, and to examine the feasibility of employing screening test at the workplace. All the workplaces that manufacture or use benzidine for more than 20 years in Korea have been covered in this study, and they include 2 benzidine manufacturing factories, 5 benzidine using factories, as well as 2 benzidine free factories as an outside control. In total, 516 workers were screened with urine stick test and urine cytology test for the evidence of hematuria and abnormal urothelial cells. Each worker was also asked about risk factors and symptoms of bladder cancer including past medical history, smoking, medication and occupational history Benzidine in the air was measured by personal and area sampling. Out of 516 screened workers, 84(16.3%) workers showed positive hematuria in urine stick test, and 7(1.4%) workers showed degenerative cells in urine cytology tests. Those workers with abnormal urine test results who have been exposed to benzidine fo more than 10 years were further screened, and, in total, 23 workers were examined with intra-venous pyelography and cystoscopy. None of those screened had any evidence of bladder cancer When workers with only past hematuria history were included in the positive hematuria group, 96(18.5%) had positive hematuria. On the multiple logistic regression analysis, positive hematuria was significantly associated with benzidine exposure, history of other occupations with elevated bladder cancer risk, pyuria and glycosuria. The association got stronger as direct benzidine exposure was accounted through individual task analysis, and as exposure duration was accounted with tenure analysis. For those with benzidine exposure with more than 10 years of tenure, the odds of having positive hematuria was elevated 2.14(95%C.I is 1.08 to 4.25) times more than for those without exposure. Even though bladder cancer was not detected for several limitations including short observation period, majority of studied workers with short latency, healthy worker effect, and low sensitivity of single screening test in a cross-sectional study, the study results suggest that hematuria screening is a feasible and very useful test for bladder cancer screening among benzidine exposed workers.

• Korean Journal of Poultry Science
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• v.11 no.2
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• pp.93-98
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• 1984

Four different silages were prepared out of citrus peel with or without supplementation with wheat bran and/or urea. Proximate nutrients and volatile fatty acids were analysed on the silages, both fresh and dried. All silages were dried and ground, and were compared with dried citrus peel (not ensiled) and wheat bran in a folding trial. A total of 360 male chicks of Maniker broiler strain was divided into and assigned to 6 treatments with 5 replications. Each experimental diet included each of 6 test material at the level of 6% and the feeding trial lasted 8 weeks, after which a metabolism trial was conducted. Results obtained were summarized as follows. 1. Ensiling increased protein content of the citrus peel on the dry matter basis and supplementing the silage material with wheat bran and/or urea further increased protein contents of the silages. 2. Adding wheat bran and/or urea to silage material also increased volatile fatty acid contents of the silages. After drying organic acid contents of the silages were reduced and there were no differences in organic acid contents of the dried citrus peel silages, differently treated, 3, Broilers fed dried citrus peel and those fed dried citrus peel silages gained numerically less weight than those fed wheat bran. But there were no significant differences in body weight gain, feed intake and feed efficiency among different treatments 4. There were no significant differences in nutrient utilizability, nitrogen retention and metabnlizable energy contents among treatments. It could be concluded that ensiling is an effective way of storing citrus peel and dried citrus peel silage could be used in broiler diets up to 6% without adverse effects.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.2
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• pp.272-277
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• 2010

This experimental study was performed to investigate the antitumor effect of Egg white combined-Chalcanthite (InSan 4, IS4) in xenografted nude mice with NCI-H460 human lung cancer cell. We cultured NCI-H460 cell lines and xenografted them on nude mice. These mice were divided into 3 groups; group with dose of 45 mg/kg IS4 orally, group with dose of 90 mg/kg IS4 orally, and the control group. They had been raised and treated for 28 days. We checked their body weight, tumor weight and volume twice a week, and their absolute organ weight, microhistological observation and biochemical blood analysis at the final day by sacrificing them. We also calculated their tumor inhibition rate (IR), mean survival time and percent increase in life span (% ILS). In this study, we observed that all of the IS4 treated mice have tumor regression, dosage-dependently, compared to the control group. Tumor weight and volume of high dose treated mice were smallest. IR increased in IS4 in a dose-dependent manner. Mean survival time and percent increase in life span (% ILS) in high-dose IS4 treatment group were the highest of the three groups. There was no significant difference in biochemical blood analysis, alanine phopsphatase (ALP), Calcium, creatinine (CRE), alanine transferase (ALT), and aspartate transaminase (AST) levels. The urea nitrogen (UN) level results significantly decreased by IS4 45 and 90 mg/kg (IS4 45 mg/kg, IS4 90 mg/kg, p<0.01). IS4 may have potential anti-tumor effect in a solid tumor induced by NCI-H460 without remarkable side effects.

• Analytical Science and Technology
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• v.10 no.6
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• pp.427-432
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• 1997

A selective method for the determination of iron(III) ion with a sodium dodecyl sulfate(SDS) modified glassy carbon electrode was proposed. It was based on the electrostatic attraction and complexation of the SDS modifier, $(DS^-)_n-Fe^{3+}$. The determination of iron(III) ion was performed by a differential pulse voltammetry(DPV), and the reduction peak potential of $(DS^-)_n-Fe^{3+}$ was +0.466(${\pm}0.002$)V vs. Ag/AgCl. For the determination of iron(III) ion, a linear calibration curve was obtained within the iron(III) ion concentration range of $0.50{\times}10^{-5}{\sim}10{\times}10^{-5}mol/L$, and the detection limit was $0.14{\times}10^{-5}mol/L$. $Cu^{2+}$, $Ni^{2+}$, $Co^{2+}$, $Pb^{2+}$, $Zn^{2+}$, and $Mn^{2+}$ showed little or no effect on the determination of iron(III) ion, respectively. But, ion such as each $CN^- $ and $SCN^-$ interfered seriously.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.4 no.4
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• pp.329-334
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• 2006

The depth distributions of total $^3H$ and $^{14}C$ activities were characterized for the activated shielding concrete from a decommissioning of KRR-2 using the commercially available tube furnace and a liquid scintillation counter. The correlation of measurement results between $^3H,\;^{14}C$ and gammer emitter was evaluated to apply for estimating radionuclide inventory of the concrete waste generated from decommissioning KRR-2. The detection limits for $^3H$ and $^{14}C$ are 0.048 and 0.028 Bq/g respectively. The specific activities of the $^3H$ and $^{14}C$ tend to decrease exponentially as the depth of the concrete becomes deeper from the surface. In addition, the $^3H$ and $^{14}C$ activities were in good correlation with the $^{60}CO$ activities analysed for the shielding concrete of KRR-2.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.12 no.2
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• pp.97-105
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• 2014

In the case of the direct measurement of $^{226}Ra$ using a HPGe gamma-ray spectrometer, the interference between gammarays with 186.21 keV of $^{226}Ra$ and 185.7 keV of $^{235}U$ should be corrected to calculate the net peak area in the energy spectrum. In general, it is very difficult to conduct peaks stripping with difference of about 0.5 keV, although a HPGe with the superior resolution is applied and the maximum channels is applied to the spectrometer. In this study, several interference correction techniques in the direct measurement were surveyed to evaluate the feasibility for the measurement of $^{226}Ra$ using the gamma-ray spectrometery. Applying the interference corrections to the analysis of raw materials and by-products, the method validation for the direct measurement of $^{226}Ra$ was conducted by evaluating the measurement uncertainty, linearity, and range. As a result, the optimum method of the interference correction was selected by comparing with the indirect measurement of which progenies of $^{226}Ra$, such as $^{214}Pb$ and $^{214}Bi$, were analyzed in the secular equilibrium state.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.147-152
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• 1996

To screen inhibitors on complement system from natural resources, micro-screening method was established by using hemolytic complement assay. Complement fixation reaction was carried out in the microplate system. For standard hemolysis (50% hemolysis) of the classical pathway (CP), hemolysin and complement serum were diluted to $1/75{\sim}1/100\;and\;1/80{\sim}1/120$, respectively, when sheep erythrocytes were $5.0{\times}10^8\;cells/ml$. In case of the alternative pathway (AP), complement serum was diluted to 1/5 and EGTA and $Mg^{2+}$ were added 4 mM, $4{\sim}8\;mM$, respectively, when rabbit erythrocytes were $4.0{\times}10^8\;cells/ml$. Dimethyl sulfoxide was used for the assay of non-aquous soluble compounds or extracts and its final concentration was not more than 1%. Three phenylpropanoids showed anticomplementary activities in proportion to the concentration for both pathways and rosmarinic acid exihibited the highest inhibitory activities: $5.4{\pm}3.6%(0.063\;mM){\sim}95.8{\pm}0.2%(0.5\;mM)\;and\;35.1{\pm}0.9%(0.063\;mM){\sim}95.6{\pm}1.1%(1\;mM)$ on the CP and the AP, respectively.

• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.497-503
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• 2008

A variety of techniques has been employed in order to reduce problems caused by the crystallization of paraffin and saturated fatty acid esters in diesel fuel containing biodiesels. Methacrylate copolymers are known as additives which reduce the pour point and cold filtering plugging point (CFPP) of diesel fuels. This paper describes the synthesis, characterization and low temperature properties, having as an initial step the synthesis of the alkyl methacrylate monomers by esterification of methacrylic acid with C12, C18, and C22 fatty alcohols. The copolymerization of these monomers with styrene was then performed, with molar ratios of 30:70, 50:50 and 70:30 for styrene:alkyl methacrylate. All copolymers were characterized by $^1H-NMR$, FT-IR, and gel permeation chromatography (GPC). The poly(styrene-co-alkyl methacrylate)s (PStmSMAn) leads to a large reduction in the pour point and CFPP of poly(styrene-co-alkyl methacrylate) in ultra low sulfur diesel (ULSD) and BD5 with treated 100~5000 ppm of poly(styrene-co-alkyl methacrylate). BD5 fuel containing 5000 ppm of the copolymer (PSt82SMA18) showed a $25^{\circ}C$ and $9^{\circ}C$ reduction in their pour points and CFPP, respectively.

• Applied Chemistry for Engineering
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• v.23 no.4
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• pp.421-427
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• 2012

To improve the lubricity of ultra low sulfur diesel, vegetable oil-based alkanol amide derivatives were prepared and their lubricity properties were studied. To synthesize the alkanol amides, we conducted the amidation reaction of diethaolamine High Frequency Reciprocating Rig (HFRR) and the fatty acid methyl esters, obtained by the continuous transesterification of methanol and several vegetable oil, such as soybean oil, palm oil and coconut oil. The synthesized amides were soluble in ultra low sulfur diesel in the concentration range of ca. 1 wt%; the lubricating properties of ultra low sulfur diesel containing 120 ppm of amides were measured using an HFRR method. It was found that the wear scar diameter in the pure ultra low sulfur diesel decreased significantly from 581 ${\mu}m$ to 305~323 ${\mu}m$ upon the addition of the amides, indicating that lubricating properties of the diesel were improved. On the other hand, the types of vegetable oils did not affect the wear scar diameters, implying that lubricating properties of the diesel did not depend strongly on the structures of alkyl groups of alkanol amide derivatives. When we measured the lubricating properties of the one type of diesels containing various amounts of alkanol amide, we observed that the wear scar diameter decreased drastically with increasing the amide concentration, meaning that the lubricity improved with the amide concentration.

• Korean Journal of Food Science and Technology
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• v.44 no.2
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• pp.251-256
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• 2012

Stilbenes are known as antioxidants and some of them demonstrate anti-pigmentation activity. The purpose of the present study was to investigate whether two stilbene compounds produced by biotransformation of the extract of $Morus$ $alba$ root show skin irritation and sensitization. In skin irritation test, 1% oxyresveratrol (OXY), and 5% OXY, and 1% oxyresveratrol-3-$O$-glucoside (OXY-3) showed a P.I.I score of 0, 0.04, and 0, respectively. Accordingly, the two stilbenes were evaluated to be virtually 'non-irritant' materials. In a skin sensitization study by GPMT, 1% OXY, 5% OXY, and 1% OXY-3 did not cause edema and erythema at 24 h and 48 h after topical application and exhibited a sensitization score of 0 and a rate of 0%. Consequently, it was confirmed that OXY and OXY-3 had no contact allergic sensitization in GPMT. Therefore, OXY and OXY-3 might be potential candidates as skin-whitening agents without posing any serious side effects.