• Journal of Life Science
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• v.23 no.8
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• pp.1025-1031
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• 2013

From a 95% ethanolic extract of H. diffusa, four marker compounds (HD1~HD4) were isolated, which were relatively unique and exist in comparably high contents. The structures of marker compounds were identified as digitolutein (1), 2-hydroxy-3-methylanthraquinone (2), (E/Z)-6-O-p-coumaroyl scandoside methyl ester (4:1 mixture) (3), and (E/Z)-6-O-p-methoxycinnamoyl scandoside methyl ester (4:1 mixture) (4), respectively, on the basis of $^{13}C$ and $^1H$-NMR analyses. The calibration curves of marker compounds showed high linearity, as their correlation coefficient ($R^2$) were in the range of 0.9991~0.9999. In addition, the limit of detection (LOD) and the limit of quantification (LOQ) were $0.03{\sim}0.07{\mu}g/ml$ and $0.099{\sim}0.231{\mu}g/ml$, respectively. The intra-day/inter-day precision and accuracy were 0.23~2.00%/0.25~1.16% and 94.60~108.44%/94.73-110.23%, respectively. The optimal HPLC conditions for the simultaneous quantification of HD1~HD4 were as follows: stationary phase; Merck Chromolith RP-18e ($100{\times}4.6mm$, $5{\mu}m$), column temp.; room temperature, UV detection at 280 nm, flow rate; 2.0 ml/min, injection volume; $10{\mu}l$, mobile phase; start with the mixture of 80% solvent A ($H_2O$ containing 0.5% acetic acid) and 20% solvent B (methanol containing 0.5% acetic acid) and gradually decrease solvent A to 40% in 9 min., then retain this condition to 18 min. Under the HPLC condition, the four marker compounds 1~4 were successfully separated without any interference of other constituents. The results obtained in this study are expected to be helpful for the development of nutraceutics and natural medicines and for the quality control of this plant.

• Journal of Food Hygiene and Safety
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• v.31 no.1
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• pp.51-58
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• 2016

This research examined the effects of Compositae extract on the inhibition of proliferation and apoptosis in human breast and human gastric cancer cells. Compositae extracts which is used in the experiment are Taraxacum coreanum (TC), Youngia sonchifolia (YS) and Ixeris dentata (ID). The proliferation of SK-BR-3, MDA-MB-231 and AGS cells were investigated by MTT assay. ID and YS extracts inhibited proliferation of SK-BR-3, MDA-MB-231 and AGS cells in a dose-dependent manner, but TC have barely affected. In addition, the most effective extract was ID. To assess the apoptosis of ID extract, the nuclei of human cancer cells were stained with DAPI solution respectively. Chromatin condensation, indicated apoptosis, was increased in a dose-dependent manner. We investigated change of ID extract-induced apoptosis proteins on human cancer cells by western blot analysis. The level of Bcl-2 decreased, whereas the level of Bax, cleaved-PARP increased in dose-dependent manner compared with non-treatment. Also Bax/Bcl-2 ratio, which is used in clinical indicator of apoptosis, was increased at ID extract treatment group compared with non-treatment. Moreover the Bax/Bcl-2 ratio of MDA-MB-231 cell was significantly increased as against SK-BR-3, AGS cells. These results indicated that ID extract have anti-proliferation effect better than YS or TC, and induced apoptosis in human breast cancer MDA-MB-231 cell better than human breast cancer SK-BR-3 cell, human gastric cancer. Even if further research is needed, ID can be developed as a chemopreventive or therapeutic agent of breast cancer.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.1
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• pp.40-49
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• 1999

A laboratory flume experiment, using turbulence-generating acryl tank and natural sediments, was conducted to investigate the effects of salinity, concentration of suspended sediment, turbulence and clay minerals on the flocculation and settling of fine-grained suspended sediments. While experiments were run, a sequence of water samples were taken near the bottom of the tank to analyze the variations of size distribution and relative contents of clay minerals. The results of the salinity experiment indicate that median settling velocity ($W_{50}$) increases linearly with salinity. Different settling processes of suspended sediments under variable concentrations appear to be predictable, depending upon the range of the suspension concentration. At concentrations less than 200 mg/l, $W_{50}$ is rarely varied with concentration probably because of the individual--grain settling mode. In the range of 200 to 13,000 mg/l show $W_{50}$ and concentration a good relationship following an empirical formula: $W_{50}=0.45C^{0.44}$. This relationship, however, no longer holds in concentrations exceeding 13,000 mg/l; instead, a more or less reverse one is shown. This result suggests an effect of hindered settling. The turbulence effect is somewhat different from that of concentration. Turbulence accelerates the flocculation and settling susepended sediments at low concentration (200 mg/l), whereas at high concentration turbulence breaks floes down and impedes the settling. Size distribution of suspended sediments sampled near the bottom of the tank tend to be more negatively skewed and leptokurtic in turbulent conditions compared to those in static conditions. The clay mineral analysis from the sequential water samples shows that over time the content of smectite decreases most rapidly with illite remaining concentrated in suspension. This means that smectite, among other clay minerals, plays the most effective role in the flocculation of fine-grained sediment in saline water.

• Journal of Korean society of Dental Hygiene
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• v.7 no.4
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• pp.583-594
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• 2007

The purpose of this study was to conduct a survey on the senses that preliminary dental hygienists have on employment, who applied for the National Dental Hygienist Examination, so that it could provide a basic reference required for fostering good human resources specializing in oral health with a sense of mission and responsibility as professional. To meet these goals, a self-administered questionnaire survey was conducted for participants in a refresher education meeting for preliminary dental hygienists across three major regions(Seoul, Daejeon and Busan), which was held by the Korean Dental Hygienists Association(KDHA) on Jan. 15, 2006. Total 289 sheets of questionnaire were collected, and 262 sheets except invalid or incomplete ones were used for examination and analysis. As a result, this study came to the following conclusions: First, it was found that 40.4% respondents wanted to be employed in dental clinic or hospital. Most respondents(90.1%) answered that faithfulness is most valued as prerequisite qualification for employment in hospital, and highest percentage of respondents(39.3%) wanted to earn 16 to 17 million Korean won annually. For internship opportunities, 61.9% respondents replied that they could willingly accept the internship, provided that basic pay and switchover to regular employee are all assured. Second, as the results of survey on employment circumstances around respondents, it was found that most respondents(58.3%) were employed in dental clinic or hospital, and highest percentage of respondents(35.0%) earned 15 to 16 million Korean won. Third, it was found that interpersonal relationships among employees had most significant effects(4.81) on selection of employment, which was followed by in-house welfare benefits 1(monthly/annual vacation, resting room, etc; 4.56). For possible influential factors on the selection of employment depending on whether employed or not, it was found that there were Significant differences in pay, welfare benefit 2(seminar, orientation, refresher training opportunities, etc), post-wedding continued employment and merit system between employees and non-employees(pE0.05). Fourth, the survey on respondents' occupational senses of dental hygienist showed that major tasks of dental hygienists were represented by oral disease prevention(92.6%), case management(71.5%), oral health education(66.3%), hospital/clinic management and dental management support(10.4%) and public oral health activities(6.7%) respectively. For job satisfaction, it was found that almost half respondents(48.9%) showed satisfaction at their job and 32.6% felt satisfied at and proud of their job. That is, majority of respondents(81.5%) felt satisfied at their job as dental hygienist. For follow-up requirements to qualify for dental hygienists, it was found that 73.3% felt it necessary to give more investments to self-development, 62.2% respondents considered protection of membership's rights as one of future assignments that KDHA should be more committed to. For future social awareness about dental hygienists as occupation, 69.2% respondents expected that they would be better developed and treated as professional. And desired training courses as a part of qualification for professional dental hygienists were represented by case management(services, manners, etc; 33.3%), implant(28.9%), esthetics(correction, prosthesis, whitening; 18.9%) and so on. For an item on working years, it was noted that 75.9% respondents would keep working as dental hygienists as long as they could.

• Journal of Food Hygiene and Safety
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• v.32 no.4
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• pp.298-305
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• 2017

Benzovindiflupyr is a new pyrazole carboxamide fungicide that inhibits succinate dehydrogenase of mitochondrial respiratory chain. This study was carried out to develop an analytical method for the determination of benzovindiflupyr residues in agricultural commodities using LC-MS/MS. The benzovindiflupyr residues in samples were extracted by using acetonitrile, partitioned with dichloromethane, and then purified with silica solid phase extraction (SPE) cartridge. Correlation coefficient ($r^2$) of benzovindiflupyr standard solution was 0.99 over the calibration ranges ($0.001{\sim}0.5{\mu}g/mL$). Recovery tests were conducted on 5 representative agricultural commodities (mandarin, green pepper, potato, soybean, and hulled rice) to validate the analytical method. The recoveries ranged from 79.3% to 110.0% and then relative standard deviation (RSD) was less than 9.1%. Also the limit of detection (LOD) and limit of quantification (LOQ) were 0.0005 and 0.005 mg/kg, respectively. The recoveries of interlaboratory validation ranged from 83.4% to 117.3% and the coefficient of variation (CV) was 9.0%. All results were followed with Codex guideline (CAC/GL 40) and Ministry of Food and Safety guideline (MFDS, 2016). The proposed new analytical method proved to be accurate, effective, and sensitive for benzovindiflupyr determination and would be used as an official analytical method.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.131-143
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• 1994

For maintenance of exposed implant in healthy state, it is necessary to treat the surface of implant fixture and provide the surface adjustable to surrounding tissues. Variable techniques have been introduced such as citric acid and air-abrasive system to treat the failed implant. Although when the rough surface of HA coated implant was exposed to oral environment, the surface treatment method with citric acid or air-abrasive system is effective for removal of bacterial endotoxin, it is unsuccessful to prevent plaque deposition due to difficulty in removal of rough surface of HA coated implant. Thus, in this study the method that removes bacterial endotoxin and makes smooch surface without alteration of surface characteristics was studied. HA coated disc manufactured by IMZ Co. Was treated with high speed diamond bur, low speed diamond bur, stone bur, rubber point, jetpolisher. And then its surface state was examined with profilometer and SEM to evaluate the surface smoothness, and its surface component was analyzed with EDX to evaluate wheter the surface characteristics were altered or not. As a result, following results were obtained. When the surface roughness of each implant disc was measured by profilometer, the group I showed a $R_{max}\;2.11{\mu}m$ and the group II, III, IV, V showed a $R_{max2}\;4.17{\mu}m$, $7.28{\mu}m$, $8.61{\mu}m$ and $39.44{\mu}m$ respectively. That is, surface smoothness was highest in the group I and it has been gradually decreased in the group II, III, IV and V. Under the SEM examination, the group I showed relatively smooth surface and the group II showed slightly rougher surface than the group I due to partially remaining HA particles while most HA particle was removed. The group III and IV showed rough topography due to HA particles that was not grinded, and HA coated surface in group V showed very irregular surface with deep groove and prominence. In cross-sectional view, the group I showed uniform surface, and the group III, IV showed rough surface due to remaining HA particles but the thickness of HA coating was remarkably reduced. The group II has similar pattern in group I, and the group V showed about $40{\mu}m$ thickness although it was not constant. By analysis of surface component with EDX, the group II in which the grinding was effective showed a small quantity of calcium and phosphorous and the group III, IV, in which the grinding was incomplete showed calcium and phosphorus peak. In all experimental group, no other than titanium, aluminum, calcium, phosphorus was observed.

• Tuberculosis and Respiratory Diseases
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• v.65 no.4
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• pp.301-307
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• 2008

Background: The triggering receptor expressed on myeloid cells-1 (TREM-1) is an activating receptor that is expressed on the surface of neutrophils and mature monocytes when stimulated with several microbial components, which can amplify the inflammatory response. This study analyzed the prognostic value of the sTREM-1 levels in patients with acute respiratory distress syndrome (ARDS). Methods: The bronchoalveolar lavage (BAL) fluid and blood was collected prospectively from 32 patients with ARDS, 15 survivors and 17 nonsurvivors. An enzyme-linked immunosorbent assay was performed to measure the sTREM-1. The following data was obtained: APACHE II score, Clinical Pulmonary Infection Score (CPIS), BAL fluid analysis, C-reative protein. Mortality in the ICU was defined as the end point. Results: The serum sTREM-1 level was significantly higher in the nonsurvivors than survivors ($54.3{\pm}10.3pg/ml$ vs. $22.7{\pm}2.3pg/ml$, p<0.05). The sTREM-1 level in the serum, but not in the BAL fluid, was an independent predictor of the ICU mortality (OR: 22.051, 95% CI: 1.780~273.148, p<0.016), and a cut-off value of ${\geq}33pg/ml$ yielded a diagnostic sensitivity of 71% and specificity of 93%. Conclusion: The serum sTREM-1 level may be a useful predictor of the outcome of ARDS patients.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.4
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• pp.329-338
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• 2010

Objective: This study was carried out to know whether cryopreservation of sibling 2PN zygotes could increase the cumulative delivery rates in the patients who had less than 10 fertilized zygotes. Methods: A retrospective analysis was performed in 138 in vitro fertilization-embryo transfer (IVF-ET) cycles with less than 10 fertilized zygotes during January 2003 to December 2007 in Cheil General Hospital. These cycles were divided into two groups. In Group I (n=86), all fertilized embryos were cultured to transfer on day 3 without cryopreserved embryos at the 2PN stage. In Group II (n=52), among fertilized zygotes, some sibling zygotes were frozen at the 2PN stage, the remainder were cultured to transfer. Clinical outcomes in fresh ET cycles and cumulative ongoing pregnancy rates after subsequent frozen-thawed (FT)-ET cycles were compared. Results: There were no significant differences in female mean age, number of retrieved oocytes and total fertilized embryos between two groups, Number of cultured embryos was significantly lower in Group II ($5.2{\pm}0.5$) than in Group I ($8.4{\pm}0.7$) (p<0.01). Also, number of transferred embryos was significantly lower in Group II ($3.3{\pm}0.6$) compared with Group I ($3.6{\pm}0.6$) (p<0.01). ${\beta}$-hCG positive rates and delivery rates (51.2 vs. 46.2 % and 41.9 vs. 34.6 %, respectively) after fresh ET were slightly higher in Group I than in Group II. However, the differences were not statistically significant. Also, the cumulative delivery rates after subsequent FT-ET cycles were not significantly different between Group I (48.8%) and Group II (50.0%). Conclusion: This study showed that cryopreservation of sibling 2PN zygotes from patients who had less than 10 zygotes in the fresh ET cycles did not increase cumulative delivery outcomes. But, it could provide an alternative choice for patients due to offering more chance for embryo transfers if pregnancy was failed in fresh IVF-ET cycles.

• Korean Journal of Agricultural Science
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• v.22 no.2
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• pp.188-196
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• 1995

To obtain useful mould strain in soybean fermentation industry, we collected conventional Meju all over the Korea and tested existance of aflatoxin in Meju collected. Also, we measured distribution of microorganism and enzyme activity of Meju and isolated Aspergillus oryzae O4-5 as a industrially useful mould. The results obtained were summarized as follows: 1. Aflatoxin was not detected by EZ-Screen Test Kit and HPLC analysis in various Meju sample collected all over the Korea from 1994.12 to 1995.2. 2. Colony forming units(CFU) of mould, yeasts, aerobe, and anaerobe were $1.3{\times}10^4-2.8{\times}10^6$, $1{\times}10^2-1.5{\times}0^6$, $2.0{\times}10^7-8.0{\times}10^8$ and $3.0{\times}10^6-7.3{\times}10^8$ per gram of Meju, respectively, indicating that CFU inter Meju samples were varied with big difference. 3. The activities of ${\alpha}$-amylase and gluco-amylase were 5-80 units and 2-34 units per g of Meju, respectively. It was shown that enzyme activity was varied depending on where the Meju was collected. 4. The activities of acidic, neutral and alkaline protease were 5-33 units, 5-302 units and 5-363 units per g of Meju, respectively. Acidic protease of Improved Meju made by D-Company was higher than that of conventional Meju as 66 units per g of Meju. 5. CNU O4-5 strain selected as a noble strain could produce amylase and protease in high level, and identified as a strain that belongs to Aspergillus oryzae. 6. The activities of acidic and neutral protease of Aspergillus oryzae CNU O4-5 strain isolated were about 10% higher than those of Aspergillus oryzae JM which has been used in soybean fermentation industry. Amylase activity of CNU O4-5 strain was similar to Aspergillus oryzae JM.

• Clinical and Experimental Pediatrics
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• v.53 no.3
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• pp.323-328
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• 2010

Purpose : To verify the effect of hyperglycemia on mortality rates in critically ill children and to identify the blood glucose level that influences prognosis. Methods : From July 2006 to June 2008, a total of 206 patients who were admitted to the pediatric intensive care unit (PICU) at Asan Medical Center and who survived for more than 7 days were retrospectively reviewed. We analyzed the maximum glucose value within 7 days in PICU, PRISM-III score and SOFA score within 24 hours, and mortality. We did not perform an adjustment analysis of drugs affecting glucose level. Results : The maximum glucose level within 7 days in PICU was higher in the nonsurvival group than in the survival group. Using 4 cutoff values (125, 150, 175, and 200 mg/dL), the mortality of patients with hyperglycemia was found to be 13.0 %, 14.4%, 19.8%, and 21.1%, respectively, and the cutoff values of 175 and 200 mg/dL revealed significant differences in mortalities between the hyperglycemic and normoglycemic groups. The PRISM-III score was not significantly different between the hyperglycemic and normoglycemic groups under a glucose cutoff value of 175 mg/dL, but the SOFA score was higher in the hyperglycemic group. Under a glucose cutoff value of 200 mg/dL, the PRISM-III score was higher in the hyperglycemic group, and the SOFA score did not differ between the 2 groups. Conclusion : Hyperglycemia with a maximal glucose value ${\geq}175\;mg/dL$ during the first 7 days after PICU admission was associated with increased mortality in critically ill children.