• IMMUNE NETWORK
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• v.14 no.5
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• pp.241-248
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• 2014

It is debatable whether AMP-activated protein kinase (AMPK) activation is involved in anti-apoptotic or pro-apoptotic signaling. AICAR treatment increases AMPK-${\alpha}1$ phosphorylation, decreases intracellular reactive oxygen species (ROS) levels, and significantly increases Annexin V-positive cells, DNA laddering, and caspase activity in human myeloid cell. AMPK activation is therefore implicated in apoptosis. However, AMPK-${\alpha}1$-knockdown THP-1 cells are more sensitive to apoptosis than control THP-1 cells are, suggesting that the apoptosis is AMPK-independent. Low doses of AICAR induce cell proliferation, whereas high doses of AICAR suppress cell proliferation. Moreover, these effects are significantly correlated with the downregulation of intracellular ROS, strongly suggesting that AICAR-induced apoptosis is critically associated with the inhibition of NADPH oxidase by AICAR. Collectively, our results demonstrate that in AICAR-induced apoptosis, intracellular ROS levels are far more relevant than AMPK activation.

• YAKHAK HOEJI
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• v.45 no.2
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• pp.161-168
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• 2001

The possible mechanism of the antiproliferative and apoptotic effects of Boswellia carterri water extract were studied in HL-60 human leukemia cells. The cytotoxicity of HL-60 cells after the treatment of Boswellia carterii water extract showed dose- and time-dependent manner. The apoptotic effect of 300 $\mu$g/ml Boswellia carterii water extract was demonstrated by DNA laddering. The activity of caspase 3-1ike protease was markedly increased in HL-60 cells treated with Boswellia carterii water extract. Furthermore, the level of Bcl-2 was time-dependently reduced, whereas Bax protein level was enhanced by Boswellia carterii water extract treatment. In conclusion, our results suggest that apoptotic effect of Boswellia carterii water extract may partly mediated through activations of caspase-3 activity and Bax expression, and inhibition of Bcl-2 expression.

• BMB Reports
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• v.38 no.3
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• pp.314-319
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• 2005

Adenosine, as a ubiquitous metabolite, mediates many physiological functions via activation of plasma membrane receptors. Mechanisms of most of its physiological roles have been studied extensively, but research on adenosine-induced apoptosis (AIA) has only started recently. In this study we demonstrate that adenosine dose-dependently triggered apoptosis of cultured baby hamster kidney (BHK) cells. Adenosine-induced apoptotic cell death was characterized by DNA laddering, changes in nuclear chromatin morphology and phosphatidylserine staining. Apoptosis was also quantified by flow cytometry. Results suggest the involvement of adenosine $A_1$ and $A_3$ receptors as well as equilibrative nucleoside transporters in apoptosis induced by adenosine. These results indicate a receptor-transporter co-signaling mechanism in AIA in BHK cells. The involvement of $A_1$ and $A_3$ receptors also implies a possible apoptotic pathway mediated by G protein-coupled receptors.

• The Journal of Information Systems
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• v.23 no.1
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• pp.93-109
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• 2014

This study aims to develop a rich understanding of user goals in user-empowering information technologies which have been dominating part in the information systems environment. A particular focus is on users' goals in a social network site (SNS) which is a typical example of user-empowering technologies. Users conduct various activities in order to achieve diverse goals in SNS. Thus, investigating what goals users pursue in SNS will give insights into understanding the users. We employed the laddering interview technique and means-end chain approach. Interviews of 50 Facebook users were analyzed to produce a hierarchical goal map showing users' goal structure. The map contains 18 goals, including self-reflection, psychological stability, belongingness, improving productivity, and amusement as ultimate goals in SNS. In the map, there are varied routes from activities to ultimate goals in SNS; that is, a complex assembly consisting of activities and goals. The findings call the information systems research community to have more interests in diverse goals and values users seek with technologies.

• Journal of the HCI Society of Korea
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• v.2 no.1
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• pp.13-24
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• 2007

For many years, human-computer interaction (HCI) practitioners have focused on usability in order to enhance the user experience, and companies have seen it as an area where they can gain advantages over their competitors. However, a focus on usability limits the potential of HCI research because it restricts the concept of user experience to just an implemented functionality of the information technology (IT). Therefore, it is necessary to expand the boundary of user experience research into a holistic dimension. We suggest that one of the most powerful ways to broadly understand user experience with an IT is to investigate the attributes of an IT and users' perceived values and to construct a user experience structure, a hierarchical structure between the attributes of an IT and users' perceived values. This study thus undertakes two research tasks: to develop a specific methodology, which is the visual probing, for constructing a user experience structure with the attributes of an IT and users' perceived values, and then to build a user experience structure practically by conducting a case study to a specific IT: mobile data service.

• Journal of Internet Computing and Services
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• v.19 no.1
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• pp.49-66
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• 2018

This research explores a value chain structure of VR-AR media including user's perception, uses, and evaluation. The purpose of this research focused on factor analysis and the relationship among user's VR-AR adoption motivations and utilities. This research explores correlation between personal value and using motivation. This study was to identify the value structure of respondent on VR-AR usages based on means-end chain theory. The research used structured APT laddering questions and 251 data was analysed. Through such analysis, category difference by stage and relationship difference were identified and hierarchical value map was compared. There are four different value ladders: first is attributes, functional consequences, psychological consequences, and final value. This study is based on the analysis of the value chain structure factors that affect VR and AR use behavior (attributes, functional benefits, psychological benefits, use value), 'Hierarchical Value Map' between users' The purpose of the model is to construct a model. For this, 'means-end chain theory' was applied to measure the causal relationship between personal value and VR related use behavior. In order to solve this research problem, 135 people were analyzed through the structured questionnaire using the AR and VR content fitness measure and the second APT laddering, and the use of VR-AR : 1) Functional benefits; 2) Psychological benefits; 3) Means to reach value, 4) Objective value chain structure was identified. The results show that VR users tried to smooth the social life through the new virtual reality audiovisual element, the newness of experience, fun, and pleasure through the departure of reality, vividness of experience, and leading fashion. The AR fitness was a game and a new program, and the value of interacting with other people and the value of 'periwinkle' played an important role through the vividness and peripheral interaction of AR, It was an important choice. The important basic values of users' VR and AR selection were correlated with psychological attributes of interaction with others, achievement, happiness and favorable values.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.152-159
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• 2015

The purpose of this study was to analyze how consumers make links between convenience meat products and self-relevant consequences and value. Surveys on convenience meat product consumption patterns and hard laddering based on means-end chain theory were conducted from April 21 to April 25, 2014 and targeted 200 consumers in the US. The most preferred cooking method of convenience meat product was roast (25.9%) and the most common information medium was suggestions by friends and parents (37.1%). The main as well as desired places of purchasing were both the supermarket (33.6% and 27.3%, respectively). The most preferred promotion method was free sample events (38.5%). From analyzing means-end chains of convenience meat products, the most dominant value chain was 'taste (A)'-'good taste (C)'-'feel good (V)'. These results show that consumption of convenience meat products will increase when consumer expectations of taste and satisfaction are met. Further, results of the value measurement provide information on consumer satisfaction and needs and can be applied to set marketing strategies for Korean style convenience meat products.

• Journal of Korea Entertainment Industry Association
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• v.15 no.3
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• pp.89-99
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• 2021

A brand community refers to a group of people who have a passion and loyalty for the brand, and is attracting attention as an effective marketing strategy to increase brand equity because it actively tends to support and promote the brand without expecting compensation. The objective of this study is to identify factors that are needed for sustainable brand community management. Existing studies on brand community management have mainly been conducted by quantitative methods measuring consumer satisfaction and dissatisfaction towards brand community activities, however, this study applied qualitative methods using means-end chains and laddering approaches in order to deeply identify a consumer's desired value on brand community activities. An in-depth interview of 41 members of BTS ARMY, a representative example of brand community, has been conducted and analyzed. The result of this study is as follows. In order to encourage active brand community activities, it is important to provide brand community members with a variety of high-quality brand-related content for a unique aesthetic experience, and a forum where all members can interact and exchange information and ideas to enhance brand value and experience. Finally, to nurture a strong brand community as a partner to co-create brand equity, rather than just a fan community, it is needed to build an environment that fosters opportunities for brand community members to increase self-respect and fulfillment through their brand community activities.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4815-4822
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• 2012

Invasion and metastasis are the major causes of cancer-related death. Pharmacological or therapeutic interventions such as chemoprevention of the progression stages of neoplastic development could result in substantial reduction in the incidence of cancer mortality. (-)-Epigallocatechin-3-gallate (EGCG), a promising chemopreventive agent, has attracted extensive interest for cancer therapy utilizing its antioxidant, anti-proliferative and inhibitory effects on angiogenesis and tumor cell invasion. In this study, we assessed the influence of EGCG on the proliferative potential of HeLa cells by cell viability assay and authenticated the results by nuclear morphological examination, DNA laddering assay and cell cycle analysis. Further we analyzed the anti-invasive properties of EGCG by wound migration assay and gene expression of MMP-9 and TIMP-1 in HeLa cells. Our results indicated that EGCG induced growth inhibition of HeLa cells in a dose- and time-dependent manner. It was observed that cell death mediated by EGCG was through apoptosis. Interestingly, EGCG effectively inhibited invasion and migration of HeLa cells and modulated the expression of related genes (MMP-9 and TIMP-1). These results indicate that EGCG may effectively suppress promotion and progression stages of cervical cancer development.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.72.1-72
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• 2003

Generally, plants defend themselves against pathogens by structural and biochemical reactions. Defense structures act as physical barriers and inhibit the pathogen from gaining entrance and spreading through the plant. Xanthomonas axonopodis pv glycines, the causal pathogen of bacterial pustule of soybean, causes hypersensitive response (HR). When pepper fruits were inoculated with X. axonopodis pv. glycines, in situ, time-series defense-related structural changes occurred in the inoculated sites. Early responses were programmed cell death (PCD), characterized by condensation and vacuolization of the cytoplasm, condensation of nuclear materials, and fragmentation of the nuclear DNA, which were observed by transmission electron microscopy. Nuclear fragmentation was proven by TUNEL method under confocal laser scanning microscopy and DNA laddering through eletrophoresis. At later stages, plant responses were cell elongation and cell division, forming a periderm-like boundary layer that demarcated healthy tissues from the inoculation sites. Using several stains such as toluidine blue, sudan IV, annexin V, and phloroglucinol-HCl, defense-related materials and structural changes were also examined.