• 대한의생명과학회지
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• 제15권2호
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• pp.127-133
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• 2009

This study was designed to investigate the effects of high concentration of (-)-epigallocatechin-3-gallate(EGCG) on the neuronal activity of rat substantia nigra dopaminergic neurons. Sprague-Dawley rats aged 14 to 16 days were decapitated under ether anesthesia. After treatment with pronase and thermolysin, the dissociated dopaminergic neurons were transferred into a chamber on an inverted microscope. Spontaneous action potentials and potassium currents were recorded by standard patch-clamp techniques under current and voltage-clamp modes respectively. 18 dopaminergic neurons(80%) revealed inhibitory responses to 40 and 100 ${\mu}M$ of EGCG and 4 neurons(20%) did not respond to EGCG. The spike frequency and resting membrane potential of these cells were decreased by EGCG. The amplitude of afterhyperpolarization was increased by EGCG. Whole potassium currents of dopaminergic neurons were increased by EGCG(n=10). These experimental results suggest that high concentration EGCG decreases the neuronal activity of the dopaminergic neurons by altering the resting membrane potential and afterhyperpolarization.

• 대한의생명과학회지
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• 제16권1호
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• pp.46-52
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• 2010

This study was designed to investigate the effects of sphingosine-1-phosphate on the neuronal activity of rat medial vestibular nuclear neurons. Sprague-Dawley rats aged 14 to 16 days were decapitated under ether anesthesia. After treatment with pronase and thermolysin, the dissociated medial vestibular nuclear neurons were transferred into a chamber on an inverted microscope. Spontaneous action potentials and potassium currents were recorded by standard patch-clamp techniques under current and voltage-clamp modes respectively. 15 medial vestibular nuclear neurons revealed excitatory responses to 1 and $5\;{\mu}M$ of sphingosine-1-phosphate. The spike frequency and resting membrane potential of these cells were increased by sphingosine-1-phosphate. The amplitude of afterhyperpolarization was decreased by sphingosine-1-phosphate. Whole potassium currents of medial vestibular nuclear neurons were decreased by sphingosine-1-phosphate (n=12). Sphingosine-1-phosphate did not affect the charybdotoxin-treated potassium currents. These experimental results suggest that sphingosine-1-phosphate increases the neuronal activity of the medial vestibular nuclear neurons by altering the resting membrane potential and afterhyperpolarization.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제12권6호
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• pp.379-385
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• 2006

가변적인 컴포넌트의 재사용성이나 적응성을 높이기 위해 룰 기반 컴포넌트 개발 방법들이 제안되고 있다. 룰 기반 컴포넌트 개발에서 사용하는 룰 엔진들은 룰을 표현하기 위해 추가적인 스크립트 언어가 필요하며 따라서 복잡한 비즈니스 룰을 표현하는데 어려움이 많다. 본 논문에서는 다양한 룰 표현과 성능 향상을 위한 컴파일러 기반의 룰 엔진을 제안한다. 제안한 룰 엔진은 룰의 컨디션과 액션 부분을 표현하기 위해 자바 프로그래밍 언어를 사용한다. 따라서 복잡한 비즈니스 룰을 쉽게 표현할 수 있으며 실행 시에 동적으로 룰의 컨디션과 액션 객체를 생성해서 실행시킬 수 있다. 성능 면에서도 제안한 룰 엔진은 스크립트 기반 룰 엔진보다 우수하다. 성능 실험에 의하면 컴파일러 기반의 룰 엔진 성능은 스크립트 기반 룰 엔진인 JSR-94 보다 2.5배의 높은 성능을 보이고 있다.

• 대한의생명과학회지
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• 제15권3호
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• pp.179-185
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• 2009

In our previous report, we showed that $PPAR{\gamma}$ does not influence adipogenesis in females with functioning ovaries, indicating that $PPAR{\gamma}$ activity on adipogenesis is associated with sex-related factors. Among the sex-related factors, estrogen has been recognized as a major factor in inhibiting adiposgenesis in females. Thus, we hypothensized that $17{\beta}$-estradiol (E) inhibits 3T3-L1 cell adipogenesis by preventing $PPAR{\gamma}$ activity. E decreased triglyceirde accumulation in differentiated 3T3-L1 cells compared with control group. E also decreased the expression of $PPAR{\gamma}$ mRNA as well as $PPAR{\gamma}$ dependent adipocyte-specific genes, such as adipocyte fatty acid binding protein and tumor necrosis factor $\alpha$. In addition, E not only decreased luciferase reporter activity by $PPAR{\gamma}$, but also transfection of estrogen receptor $\alpha$ ($ER{\alpha}$) or $ER{\beta}$ led to decreases in $PPAR{\gamma}$ reporter gene activation. Moreover, E-activated ERs significantly decreased the luciferase reporter gene activation induced by $PPAR{\gamma}$ transfection, suggesting that estrogen-activated ERs inhibit $PPAR{\gamma}$-dependent transactivation. Accordingly, our results demonstrate that E inhibits the action of $PPAR{\gamma}$ on adipogenesis through E activated ER, providing evidence that lack of estrogen may potentiate $PPAR{\gamma}$ action on adipogenesis.

• 한국미생물·생명공학회지
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• 제20권5호
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• pp.498-504
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• 1992

고구마효소 갈변반응생성물(SPEBRP)의 항돌연변이 효과를 검토하기 위하여 DNA breaking test, spore rec assay, Ames test를 행하였다. DNA breaking test에서 catechol- 및 hydroxyhydroquinone-SPEB-RPs는 $Fe^{2+}$ 존재하에서 DNA breaking effect를 저해하였다. Bacillus subtilis H17(rec+) 및 M45(rec-)를 이용한 spore rec assay엣 3,4-dihydroxytoluene-SPEBRP는 MNNG에 대하여 강한 돌연변이 효과를 나타내었다. Salmonella typhimurium TA98 및 TA 100를 이용한 Ames test에서 pyrogallol-, 3,4-dihyd-roxytoluene-, hydroxyhydroquinone-SPEBRPs 들은 발암물질인 Benzo($\alpha$)Pyrene에 대하여 67.71, 63%의 강한 활성억제를 나타내었다.

• 한국미생물·생명공학회지
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• 제13권2호
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• pp.103-107
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• 1985

B. subtilis의 항생물질 내성균주에 대하여 여러 plasmid curing 시약인 sodium dodecyl sulfate, acriflavine, ethidium bromide, mitomycin-C등을 처리하여 streptomycin 감수성 변이주를 만들었다. Sodium dodecyl sulfate 처리의 경우 0.1% 농도에서 균체성장 극대기에 도달한 후부터 항생물질 감수성 비율이 증가되었으며, acriflavine 처리의 경우는 4$\mu\textrm{g}$/$m\ell$ 농도에서, ethidium bromide 처리의 경우에는 10$\mu\textrm{g}$/$m\ell$ 농도에서. 그리고 mitomycin-C 처리의 경우에는 200$\mu\textrm{g}$/$m\ell$ 농도에서 가장 curing빈도가 높았다. 또 이들 curing 작용은 B. subtilis의 streptomycin과 terramycin 내성균주에서 보는 바와 같이 경쟁적 작용으로 일어났다.

• International journal of advanced smart convergence
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• 제8권1호
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• pp.176-183
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• 2019

Rhyme of Truce is an educational program that helps you develop the ability to cope with cyber violence rightly. we aim to produce educational contents that will last a long time in the memory of specially children. By combining the room escape game and Leap motion / VR, the program reflects the user's motion and action in real time. The Keyboard Worrier comes into contact with the user and causes violence, and the user who is attacked by the monster see several negative messages written in red and hears abuses sound. Users enter the virtual space decorated as the cyber world. They can experience cyber-violence indirectly but vividly, and if language violence, which has been overlooked and recognized only as "letters", is executed offline, it will directly wonder if cyber-violence should also be regarded as a means of violence. Users have the opportunity to cope with violence autonomously. When a user is attacked by an in-game monster, there are two ways to choose from. First, fighting against with a keyboard (which is a symbol of language violence) just like a monster. Second, report the abuser to cyber bureau police. Both methods make them to escape the room, but when they get out of the room and return to the home and read the message through the monitor, users can recognize which action was right for.

• 한국미생물·생명공학회지
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• 제48권4호
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• pp.429-438
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• 2020

The emergence of multi-drug resistant, pathogenic methicillin-resistant Staphylococcus aureus (MRSA) is a threat to global health and has created a need for novel functional therapeutic agents. In this study, we evaluated the underlying mechanisms of the anti-MRSA effect of an azaphilone pigment, sclerotiorin (SCL) from Penicillium sclerotiorum. The antimicrobial activity of SCL was evaluated using agar disc diffusion, broth microdilution, time-kill assays and biophysical studies. SCL exhibits selective activity against Gram positive bacteria including MRSA (range, MIC = 128-1028 ㎍/ml) and exhibited rapid bactericidal action against MRSA with a > 4 log reduction in colony forming units within three hours of administration. Biophysical studies, using fluorescent probes and laser or electron microscopy, demonstrated a SCL dose-dependent alternation in membrane potential (62.6 ± 5.0.4% inhibition) and integrity (> 95 ± 2.3%), and the release of UV260 absorbing materials within 60 min (up to 3.2 fold increase, p < 0.01) of exposure. Further, SCL localized to the cytoplasm and hydrolyzed plasmid DNA. While in vitro checkerboard studies revealed that SCL potentiated the antimicrobial activity of topical antimicrobials such as polymixin, neomycin, and bacitracin (Fractional Inhibitory Concentration Index range, 0.26-0.37). Taken together these results suggest that SCL targets the membrane and DNA of MRSA to facilitate its anti-MRSA antimicrobial effect.

• 한국미생물·생명공학회지
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• 제48권2호
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• pp.148-157
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• 2020

Eucalyptus oil is a rich source of bioactive compounds with a variety of biological activities and is widely used in traditional medicine. Eucalyptus citriodora is cultivated for the production of essential oils. However, the mode of antibacterial action of essential oils from E. citriodora is not well-known. This study aimed to determine the chemical components, microbial inhibitory effect, and mechanism of action of the essential oil from E. citriodora. The oil was extracted from E. citriodora leaves by hydro-distillation and the chemical components were analyzed using gas chromatography-mass spectrometry. The antibacterial activities of eucalyptus oil against gram-positive bacteria (Bacillus subtilis, Staphylococcus aureus, and Staphylococcus intermedius) and gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) were screened by disc diffusion method and quantitative analysis was conducted by the microdilution method. The mechanism of action of the extracted essential oil was observed using SEM and analyzed by SDS-PAGE. The major components of E. citriodora oil were citronellal (60.55 ± 0.07%), followed by dl-isopulegol (10.57 ± 0.02%) and citronellol (9.04 ± 0.03%). The antibacterial screening indicated that E. citriodora oil exhibited prominent activity against all tested strains. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against B. subtilis were 0.5% and 1.0%, respectively. The MIC and MBC concentrations against S. aureus, S. intermedius, E. coli, and P. aeruginosa were 1% and 2%, respectively. As observed by SEM, the antibacterial mechanism of E. citriodora oil involved cell wall damage; SDS-PAGE revealed decrease in protein bands compared to untreated bacteria. Thus, E. citriodora oil showed significant antimicrobial properties and caused cellular damage.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제6권1호
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• pp.58-67
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• 2000

엔터프라이즈 네트웍의 크기가 커지고 그 관리 범위가 넓어짐에 따라 분산 망 관리 시스템의 수용을 요구하게 되었고 또한 표준 프레임웍들간의 상호 연결 및 작용이 필요하게 되었다. 이 논문에서는 네트웍 관리 프레임웍인 SNMP도메인과 분산 객체 기술의 하나인 CORBA도메인간의 통합 관리를 위한 구현 방안을 제시한다. 표준에서 사용하는 직접 변환은 객체 지향적인 특성을 표현하고 있지 않으며, action을 위한 속성의 정의가 다른 속성과 구별되지 않는 등의 한계를 지니고 있다. 이러한 한계점은 추상적 변환 방법을 통해 새로운 클래스의 정의, 명확한 메쏘드 정의라는 방법으로 충분히 극복될 수 있다. 직접 변환의 편리함과 추상적 변환의 효율적인 관리 정보의 구축이라는 장점을 이용한 직접 변환과 추상적 변환의 혼용을 통한 정보 모델 변환 방법을 이용한 게이트웨이의 개발 방법을 제시한다. 이러한 통합 관리 시스템 구축은 CORBA/SNMP 간의 효율적인 통합 관리를 제공한다.