• Biomedical Science Letters
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• v.29 no.4
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• pp.211-219
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• 2023

Caffeic acid phenethyl ester (CAPE) is an active component of propolis obtained from honeybee hives. CAPE possesses anti-mitogenic, anti-carcinogenic, anti-inflammatory, and immunomodulatory activities in diverse systems, which know as displays antioxidant activity and inhibits lipoxygenase activities, protein tyrosine kinase, and nuclear factor kappa B (NF-κB) activation. This study aimed to investigate the effect of CAPE on lipopolysaccharide (LPS)-induced human neutrophil phagocytosis. Human neutrophils were cultured with various concentrations of CAPE (1, 10, and 100 µM) with or without LPS. The pro-inflammatory proteins (tumor necrosis factor-alpha [TNF-α], interleukin [IL]-6 and IL-8) levels were measured after 4 h incubation. To investigate the intracellular signaling pathway, we measured the levels of mitogen-activated protein kinases (MAPK), including phosphorylation of p38, extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) and c-Jun N-terminal kinase (JNK). Next, to evaluate the potential phagocytosis, neutrophils were labeled with iron particles of superparamagnetic iron oxide nanoparticles (SPIONs, 40 nm) for 1 h in culture medium containing 5 mg/mL of iron. The labeling efficiency was determined by Prussian blue staining for intracellular iron and 3T-wighted magnetic resonance imaging. CAPE decreased the activation of intracellular signaling pathways, including ERK1/2 and c-Jun, and expression of pro-inflammatory cytokines, including TNF-α and IL-6, but had no effect on the signaling pathways of p38 and cytokine IL-8. Furthermore, images obtained after mannan-coated SPION treatment suggested that CAPE induced significantly higher signal intensities than the control or LPS group. Together, these results suggest that CAPE regulates LPS-mediated activation of human neutrophils to reduce phagocytosis.

• Journal of Microbiology and Biotechnology
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• v.27 no.12
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• pp.2129-2140
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• 2017

Silibinin is the major active component of silymarin, extracted from the medicinal plant Silybum marianum. Silibinin has potent antibacterial activity; however, the exact mechanism underlying its activity has not been elucidated. Here, we investigated the novel mechanism of silibinin against Escherichia coli. Time-kill kinetic assay showed that silibinin possess a bactericidal effect at minimal inhibitory concentration (MIC) and higher concentrations (2-and 4-fold MIC). At the membrane, depolarization and increased intracellular $Ca^{2+}$ levels were observed, considered as characteristics of bacterial apoptosis. Additionally, cells treated with MIC and higher concentrations showed apoptotic features like DNA fragmentation, phosphatidylserine exposure, and caspase-like protein expression. Generally, apoptotic death is closely related with ROS generation; however, silibinin did not induce ROS generation but acted as a scavenger of intracellular ROS. These results indicate that silibinin dose-dependently induces bacterial apoptosis-like death, which was affected by ROS depletion, suggesting that silibinin is a potential candidate for controlling bacteria.

• Journal of Microbiology and Biotechnology
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• v.30 no.3
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• pp.382-390
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• 2020

Periplanetasin-4 is an antimicrobial peptide with 13 amino acids identified in cockroaches. It has been reported to induce fungal cell death by apoptosis and membrane-targeted action. Analogs were designed by substituting arginine residues to modify the electrostatic and hydrophobic interactions accordingly and explore the effect of periplanetasin-4 through the increase of net charge and the decrease of hydrophobicity. The analogs showed lower activity than periplanetasin-4 against gram-positive and gram-negative bacteria. Similar to periplanetasin-4, the analogs exhibited slight hemolytic activity against human erythrocytes. Membrane studies, including determination of changes in membrane potential and permeability, and fluidity assays, revealed that the analogs disrupt less membrane integrity compared to periplanetasin-4. Likewise, when the analogs were treated to the artificial membrane model, the passage of molecules bigger than FD4 was difficult. In conclusion, arginine substitution could not maintain the membrane disruption ability of periplanetasin-4. The results indicated that the attenuation of hydrophobic interactions with the plasma membrane caused a reduction in the accumulation of the analogs on the membrane before the formation of electrostatic interactions. Our findings will assist in the further development of antimicrobial peptides for clinical use.

• BMB Reports
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• v.53 no.7
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• pp.385-390
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• 2020

Inflammatory Bowel Disease is caused by an acute or chronic dysfunction of the mucosal inflammatory system in the intestinal tract. In line with the results of our previous study, wherein we found that the PKCα-LSD1-NF-κB signaling plays a critical role in the prolonged activation of the inflammatory response, we aimed to investigate the effect of signaling on colitis in the present study. Lsd1 S112A knock-in (Lsd1^SA/SA) mice, harboring a deficiency in phosphorylation by PKCα, exhibited less severe colitis symptoms and a relatively intact colonic epithelial lining in dextran sulfate sodium (DSS)-induced colitis models. Additionally, a reduction in pro-inflammatory gene expression and immune cell recruitment into damaged colon tissues in Lsd1^SA/SA mice was observed upon DSS administration. Furthermore, LSD1 inhibition alleviated colitis symptoms and reduced colonic inflammatory responses. Both LSD1 phosphorylation and its activity jointly play a role in the progression of DSS-induced colitis. Therefore, the inhibition of LSD1 activity could potentially protect against the colonic inflammatory response.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.1
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• pp.29-35
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• 2019

Decursin is a major biological active component of Angelica gigas Nakai and is known to induce apoptosis of metastatic prostatic cancer cells. Recently, other reports have been commissioned to examine the anticancer activities of this plant. In this study, we evaluated the inhibitory activity and related mechanism of action of decursin against glioblastoma cell line. Decursin demonstrated cytotoxic effects on U87 and C6 glioma cells in a dose-dependent manner but not in primary glial cells. Additionally, decursin increased apoptotic bodies and phosphorylated JNK and p38 in U87 cells. Decursin also down-regulated Bcl-2 as well as cell cycle dependent proteins, CDK-4 and cyclin D1. Furthermore, decursin-induced apoptosis was dependent on the caspase activation in U87 cells. Taken together, our data provide the evidence that decursin induces apoptosis in glioblastoma cells, making it a potential candidate as a chemotherapeutic drug against brain tumor.

• Journal of the Korean Society of Clothing and Textiles
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• v.45 no.2
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• pp.217-232
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• 2021

This study analyzed the characteristics of generation Z leading the trend of the fashion industry through the creative activity of Virgil Abloh. A literature review and case study were conducted together with detailing the research methodology. As a result of research, generation Z is conceptualized as a "digital native" who grows in digital technology environment with excellent visual sense. They are "SNS creators" who have influence on Social Networking Services (SNS). They are also characterized as "social activists" who reject social conventions and prejudices. They are a "leading creators" who seek to differentiate with creativity. The characteristics of generation Z in the creative activities of Virgil Abloh have a feature of digital native in that they seek visual originality. In terms of communicating with generation Z through SNS and influencer marketing, it has the characteristics of SNS creators. It expresses social activists in providing consumers with diversity, and social perceptions of differentiation. In terms of providing content that encourages consumers to express their personality, it has a feature of leading creators. It is meaningful in that it contributes to the understanding of the market change and marketing strategy according to the consumer development and the activity of the fashion designer.

• Journal of The Korean Association For Science Education
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• v.33 no.1
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• pp.114-131
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• 2013

In this study, FAISC (Family Activity for Improving Scientific Creativity) program was developed and applied to 12 families. FAISC consists of 12 tasks and 12 evaluation papers. Family participants conducted the task individually and evaluated their performance results through discussion and agreement. From the participants' responses, it was found that FAISC tasks were fun but weakly difficult. Participants responded that Guide 1 (Creative thinking methods) and Guide 2 (Related knowledge) were helpful in their performance, and their scientific creativity was enhanced. From the analysis of interview and video recording of participants' behaviors, various positive aspects were observed. Especially on cognitive aspects, harmonious and pleasant family activities were observed. Negative aspects observed in interview and video gave us a practical guide for more effective performance in further application. Finally, according to comparison of evaluation results by family and professionals, the correlation between them was .901. Therefore, we conclude that evaluation of creative activity by family is highly confidential.

• Animal cells and systems
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• v.13 no.4
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• pp.357-362
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• 2009

Hesperidin, the most abundant polyphenolic compound found in citrus fruits, has been known to possess neuroprotective, sedative, and anticonvulsive effects on the nervous system. In a recent electrophysiological study, it was reported that hesperidin induced biphasic change in population spike amplitude in hippocampal CA1 neurons in response to both single spike stimuli and theta-burst stimulation depending on its concentration. However, the precise mechanism by which hesperidin acts on neuronal functions has not been fully elucidated. Here, using whole-cell patch-clamp recording, we revealed that hesperidin did not affect excitatory synaptic activities such as basal synaptic transmission and theta-burst LTP. Moreover, in a current injection experiment, spike number, resting membrane potential and action potential threshold also remained unchanged. Taken together, these results indicate that the effects of hesperidin on the neuronal functions such as spiking activity might not be attributable to either modification of excitatory synaptic transmissions or changes in membrane excitability in hippocampal CA1 neuron.

• Proceedings of the Korea Information Processing Society Conference
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• 2016.04a
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• pp.344-347
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• 2016

유비쿼터스 환경 시대에 맞춰 현재 스마트 디바이스의 발달과 시장의 확대로 스마트 미디어 기기의 보급이 급속도로 확산되고 있으며 많은 교육용 어플리케이션 또한 개발되고 있는 중이다. 이러한 교육용 어플리케이션들은 지식기반사회의 학습도구로서 지식접근 및 창출에 중요한 요소인 인터넷과 웹을 활용하게 되고 이동성과 편의성을 추구하는 모바일기기를 통해 학습이 가능하도록 지원하는 프로그램이다. 본 연구는 모바일러닝 기반의 '창의적 문제해결(CPS, Creative Problem Solving)' 모형을 활용하는 교육용 앱에 대한 설계방안을 제시하고자 하며 연구의 목적은 대학 교육에서 학생들의 창의적 사고와 문제해결능력 향상을 돕는 모바일러닝 기반의 학습환경을 설계하는 데 있다. 제안하는 학습지원 도구는 모바일 앱 형태로 제작되며 학습활동에 있어 다양한 창의적 사고과정 활동과 표현방식, 상호작용성 등의 기능을 통해 학습자의 고차원적인 사고능력을 향상시키는 인지적 도구로서 활용될 수 있도록 설계하였다. 개발환경은 안드로이드용 앱 인벤터 프로그램을 사용하였으며 앱 인벤터 서버환경에서 제공되는 컴포넌트와 이벤트 핸들러를 이용하여 교수자모드와 학습자모드의 앱을 각각 설계하였다. 교수자 앱은 학습활동 제공을 의미하는 프로바이더(Provider) 모드 기능이 포함되며 학습자 앱은 CPS 활동을 위한 학습활동 모드 기능이 설계된다. 대부분의 창의성 관련 앱들은 그래픽작업을 통한 두뇌활동 향상 프로그램, 체험활동 위주의 프로그램 등으로 출시가 되어 있으나 교수-학습 활동을 위한 창의적 문제해결활동 관련 앱은 존재하지 않는 상태이므로 수업활동에서의 활용측면에서 가치가 있을 것으로 기대된다.

• Journal of Engineering Education Research
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• v.15 no.2
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• pp.30-37
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• 2012

There have been various educational approaches to foster students' creativity in engineering colleges, but little has been conducted based on empirical study results of students' perception on creativity education. This study aims to explore the students' perception on creativity in engineering such as characteristics of creative engineers, the level of individual or group creativity and creative education in engineering colleges. According to the survey results of 538 respondents, engineering students considered three factors such as 'innovative driven', 'eager for high intellectuality', 'activity expression' as characteristics of creative engineer. They evaluated both of individual or group creativity levels as subnormal. They perceived the importance of creativity education, but were not satisfied with current creativity educational experiences. They pointed out 'limited supports of nation or organization', 'credit system decided by the paper-based exam', 'non-systematized creativity classes' as impending factors for creativity in engineering education. Students suggested 'securing the budget for practice and field participation', 'changing of perception on creativity education itself', 'developing the creativity classes combined with engineering subjects' as fostering factors in creativity education. This studdy suggests several implications of educational approaches to creativity education in engineering colleges.