• Journal of Microbiology and Biotechnology
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• v.33 no.6
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• pp.780-787
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• 2023

Two mannitol producing lactic acid bacteria were isolated from pa (green onion)- kimchi, identified and named as Leuconostoc mesenteroides SKP 88 and Leuconostoc citreum SKP 92, respectively. Both isolates grew well at 25-30℃, initial pH 6-8, and 3% and lower NaCl concentration. Both isolates converted fructose into mannitol efficiently when grown on MRS broth containing fructose and glucose. Glucose was used as a carbon source and fructose was used as a precursor for mannitol. Mannitol yields were the highest in MRS broth with 3% fructose and 2% glucose. Shine muscat juice fermentation was done using each isolate as a starter. As fermentation progressed, decrease in pH and increases in titratable acidity and viable counts were observed. L. mesenteroides SKP 88 showed better mannitol conversion ability than L. citreum SKP 92, and shine muscat juice fermented with L. mesenteroides SKP 88 showed the mannitol production of 41.6 g/l at 48 h, and juice fermented with L. citreum SKP 92 showed 23.4 g/l at the same time. Yogurt fermentations showed similar patterns, and yogurt fermented with L. mesenteroides SKP 88 showed the mannitol production of 15.13 g/l. These results showed that both strains are useful as starters for healthy fermented foods with reduced fructose contents.

• Journal of Gastric Cancer
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• v.1 no.2
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• pp.83-91
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• 2001

Purpose: This study was to observe whether the apoptotic function of tumor-infiltrating lymphocytes (TIL) is induced in human gastric epithelial dysplasia and gastric adenocarcinoma according to the role of FasL expression. Materials and Methods: A total of 56 gastric epithelial dysplasia and gastric adenocarcinoma patients were enrolled in this study: 9 cases of gastric epithelial dysplasia, 18 cases of early gastric carcinomas (EGC) and 29 cases of advanced gastric carcinomas (AGC). Immunohistochemical staining was performed for FasL and CD45, and the terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL) method was used to detect cell death in tumor-infiltrating lymphocytes. Results: 1) Positive reactions of FasL to neoplastic cells were $88.9\%$ (8/9) in gastric epithelial dysplasia, $83.3\%$ (15/18) in EGC, and $75.9\%$ (22/29) in AGC. 2) Expression of TIL was decreased in the FasL positive region and was increased in the FasL negative region, and significant expression of TIL was observed in the AGC group (P=0.001). 3) Expression of apoptotic TIL was very similar to the FasL expression, and $100\%$ expression was observed in gastric epithelial dysplasia group. 4) Expression of apoptotic TIL was increased in the FasL positive region and decreased in the FasL negative region, and significant apoptotic expression was observed in the gastric epithelial dysplasia and EGC groups (P=0.0420, P=0.0263, respectively). Conclusion: These results suggest that FasL is a prevalent mediator of immune privilege in epithelial dysplasia and cancer of the stomach.

• The Journal of Advanced Prosthodontics
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• v.8 no.3
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• pp.172-180
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• 2016

PURPOSE. The purpose of this study was to analyze the antimicrobial, antioxidant activity and cytotoxicity of Dendropanax morbifera $L{\acute{e}}veille$ extract for assessing whether Dendropanax morbifera $L{\acute{e}}veille$ can be used for the development of natural mouthwash and denture cleaning solution. MATERIALS AND METHODS. The extract was obtained from branches of Dendropanax morbifera $L{\acute{e}}veille$. The solvent fractions were acquired by fractionating Dendropanax morbifera $L{\acute{e}}veille$ extract using n-hexane, ethyl acetate, chloroform and butanol solvent. Paper disc test was used to evaluate the antimicrobial and antifungal activity of Dendropanax morbifera $L{\acute{e}}veille$ extract and solvent fractions against Streptococcus mutans and Candida albicans. The analysis of antioxidant activity was carried out through DPPH radical scavenging assay. The cytotoxicity of Dendropanax morbifera $L{\acute{e}}veille$ extract was analyzed through MTT assay using normal human oral keratinocytes. RESULTS. Dendropanax morbifera $L{\acute{e}}veille$ extract showed antimicrobial activity against Streptococcus mutans and especially Candida albicans. The solvent fractions of Dendropanax morbifera $L{\acute{e}}veille$ showed strong antimicrobial activity against Streptococcus mutans and Candida albicans in n-hexane and butanol solvent fraction, respectively. Dendropanax morbifera $L{\acute{e}}veille$ extract also showed outstanding antioxidant activity. Butanol, ethyl acetate, and chloroform solvent fraction of Dendropanax morbifera $L{\acute{e}}veille$ tended to have increased antioxidant activity as the concentration increased. Dendropanax morbifera $L{\acute{e}}veille$ extract showed high cell survival rate in cytotoxicity test. CONCLUSION. Dendropanax morbifera $L{\acute{e}}veille$ extract turned out to have antimicrobial, antioxidant activity and cytophilicity. Based on these results, it is expected that Dendropanax morbifera $L{\acute{e}}veille$ is applicable as an ingredient for natural mouthwash and denture cleanser.

• Journal of Dental Anesthesia and Pain Medicine
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• v.18 no.3
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• pp.143-149
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• 2018

Background: We evaluated the changes in mean arterial pressure (MAP) and heart rate (HR), and the anesthetic and hemostatic effects, after injection of 2% lidocaine containing various concentrations of epinephrine in rats and mice to determine the appropriate concentration of epinephrine in various anesthetic mixtures. Methods: Rats and mice were randomly allocated to experimental groups: 2% lidocaine without epinephrine (L0), 2% lidocaine with epinephrine 1:200,000 (L200), 1:100,000 (L100), and 1:80,000 (L80). Changes in MAP and HR after administration of the anesthetic mixture were evaluated using a physiological recording system in rats. Onset and duration of local anesthesia was evaluated by pricking the hind paw of mice. A spectrophotometric hemoglobin assay was used to quantify the hemostatic effect. Results: MAP increased in response to epinephrine in a dose-dependent manner; it was significantly higher in the L80 group than in the L0 group at 5 min post-administration. The HR was relatively lower in the L0 group than in the L80 group. The time required for onset of action was < 1 min in all evaluation groups. The duration of action and hemostatic effect of the local anesthetic were significantly better in the L200, L100, and L80 groups than in the L0 group. Conclusion: L200 demonstrated relatively stable MAP and HR values with satisfactory efficacy and hemostatic effect. L200 might be a better local anesthetic for dental patients in terms of anesthetic efficacy and safety.

• Journal of the Korean Chemical Society
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• v.56 no.5
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• pp.661-664
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• 2012

• Biotechnology and Bioprocess Engineering:BBE
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• v.7 no.3
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• pp.171-177
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• 2002

The metabolic flux pattern for L-histidine production was analyzed when glucose and/or acetate were used as carbon sources. Total L-histidine production was enhanced when mixed substrate (glucose and acetate) was used, compared wish that when either glucose or acetate was used as the sole carbon source. Theoretical maximum carbon fluxes through the main pathways for L-histldine production, cell growth, and ATP consumption for cell maintenance were obtained by the linear programming (LP) method. By comparison of the theoretical maximum carbon fluxes tilth actual ones, it was found that a large amount of glucose was actually used for maintenance of cell viability. On the other hand, acetate was used for cell growth. After depletion of acetate in the mixed substrate culture, the flux for glucose to L-histldine synthesis was markedly enhanced. A strategy for effective L-histidine production using both carbon sources was proposed.

• Journal of the Korean Chemical Society
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• v.43 no.2
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• pp.28-231
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• 1999

• International Journal of Industrial Entomology and Biomaterials
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• v.9 no.1
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• pp.29-33
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• 2004

Low molecular weight silk fibroin (LMSF), which was prepared by hydrolysis of silk fibroin using high-temperature and high-pressure method, was found to inhibit the oxidation of L-3,4,-dihydroxyphenylalanine (L-DOPA) catalyzed by mushroom tyrosinase (EC 1.14.18.1). LMSF contained mostly free amino acids such as L-glycine, L-alanine, and L-serine and oligopeptides, mainly glycine-alanine dimer. As a result of analyzing the inhibition kinetics from Lineweaver-Burk plots, L-glycine and glycine-alanine dimer showed noncompetitive behavior while uncompetitive behavior was observed in L-alanine, and L-serine. When weight percent concentration of ${ID_50}$ was compared, L-glycine was most effective on the inhibition and LMSF was also good enough for the inhibition effect of tyrosinase activity. LMSF showed a mixed-type inhibition and the inhibitory mechanism of LMSF might be caused by free amino acids and oligopeptides. As a result of spectroscopic observation with time, initial rate of increase of DOPAchrome decreased remarkably and the time to reach maximum absorbance increased as an increase of the concentration of L-glycine, meaning that L-glycine made itself mainly responsible for the formation of chelate with ${Cu^2+}$ in tyrosinase. However, in case of L-alanine, L-serine, and especially glycine-alanine dimmer, the production of DOPAchrome after an arrival at maximum absorbance decreased, indicating the production of adducts through the reaction with DOPAquinone.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.452-455
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• 2005

The cutting characteristics of hardened steel by a PCBN tool is investigated with respect to workpiece surface roughness, cutting force and tool flank wear of the vision system. Backpropagation neural networks (BPNs) were used for detection of tool wear. The neural network consisted of three layers: input, hidden and output. The input vectors comprised of spindle rotational speed, feed rates, vision flank wear, and thrust force signals. The output was the tool wear state which was either usable or failure. Hard turning experiments with various spindle rotational speed and feed rates were carried out. The learning process was performed effectively by utilizing backpropagation. The detection of the abnormal states using BPNs achieved 96.4% reliability even when the spindle rotational speed and feedrate were changed.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.378-381
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• 2009

유비쿼터스 센서네트워크는 다양한 환경에서 여러 가지 요구사항에 부합하기 위해 미들웨어 모델들을 필요로 하게 되었다. 지금까지 제안된 미들웨어 구조들은 특정 응용에 초점을 맞추거나 여러 가지 요구사항들을 수용하기에 적절치 않은 구조를 가지고 있다. 본 논문에서는 유비쿼터스 센서네트워크 환경에서 L4 마이크로커널 기반으로 미들웨어 시스템을 구성하는 것을 제안한다. L4 마이크로커널은 대표적인 2세대 마이크로 커널로써, 기존의 모놀리틱 커널의 구조적 문제점을 극복하기 위한 대안이 될 수 있다. 기존의 모놀리틱 커널은 임베디드시스템, 실시간 시스템과 같은 특수한 목적을 수행하는 시스템을 설계하는데 많은 제약사항을 가지고 있다. 유비쿼터스 센서네트워크 환경에서 L4 마이크로커널을 통한 시스템 구성은 전체 시스템의 안정성과 독립성을 보장하며, 특정 상황에 맞게 새로운 솔루션을 추가할 수 있는 유연성을 제공한다.