• The Journal of Korean Academy of Prosthodontics
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• v.43 no.6
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• pp.751-763
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• 2005

Statement of problem. To improve a direct implant fixation to the bone, various strategies have been developed focusing on the surface of materials. The surface quality of the implant depends on the chemical, physical, mechanical and topographical properties of the surface. The different properties will interact with each other and a change in thickness of the oxide layer may also result in a change in surface energy, the surface topography and surface, chemical composition. However, there is limited the comprehensive study with regard to changed surface and biologic behavior of osteoblast by anodization. Purpose of study. The aim of this study was to analyze the characteristics of an oxide layer formed and to evaluate the cellular biologic behaviors on titanium by anodic oxidation (anodization) by cellular proliferation, differentiation, ECM formation and gene expression. And the phospholipase activity was measured on the anodized surface as preliminary study to understand how surface properties of Ti implant are transduced into downstream cellular events. Methods and Materials. The surface of a commercially pure titanium(Grade 2) was modified by anodic oxidation. The group 1 samples had a machined surface and other three experimental specimens were anodized under a constant voltage of 270 V(Group 2), 350 V(Group 3), and 450 V(Group 4). The specimen characteristics were inspected using the following five categories; the surface morphology, the surface roughness, the thickness of oxide layer, the crystallinity, and the chemical composition of the oxide layer. Cell numbers were taken as a marker for cell proliferation. While the expression of alkaline phosphatase and Runx2 (Cbfa1) was used as early differentiation marker for osteoblast. The type I collagen production was determined, which constitutes the main structural protein of the extracellular matrix. Phospholipase $A_2$ and D activity were detected. Results. (1) The anodized titanium had a porous oxide layer, and there was increase in both the size and number of pores with increasing anodizing voltage. (2) With increasing voltage, the surface roughness and thickness of the oxide film increased significantly (p<0.01), the $TiO_2$phase changed from anatase to rutile. During the anodic oxidization, Ca and P ions were more incorporated into the oxide layer. (3) The in vitro cell responses of the specimen were also dependant on the oxidation conditions. With increasing voltage, the ALP activity, type I collagen production, and Cbfa 1 gene expression increased significantly (p<0.01), while the cell proliferation decreased. (4) In preliminary study on the relation of surface property and phospholipase, PLD activity was increased but $PLA_2$ activity did not changed according to applied voltage. Conclusion. The anodized titanium shows improved surface characteristics than the machined titanium. The surface properties acquired by anodization appear to give rise more mature osteoblast characteristics and might result in increased bone growth, and contribute to the achievement of a tight fixation. The precise mechanism of surface property signaling is not known, may be related to phospholipase D.

• The Journal of Korean Medicine
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• v.27 no.4
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• pp.12-29
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• 2006

Background and Aims : Even though various strategies for cancer treatment have advanced with the remarkable development of genomic information and technology, it is far from giving relief to cancer patients. Recently there is accumulating evidence that the immune system is closely connected to anti-tumor defense mechanisms in a multistage process. This includes tumorigenesis, invasion, growth and metastasis. Cordyceps Militaris, a well-known oriental herbal medicine, is a parasitic fungus that has been used as an immune enhancing agent for a long period of time. However, little is known about the cancer-related immunomodulatory effects and anti-tumor activities. In the present study, we aimed to investigate the effects of Cordyceps Militaris extract (CME) on immune modulating and anti-tumor activity. Materials and Methods : To elucidate the effects of CME on macrophage and natural killer (NK) cell activity, we analyzed nitric oxide (NO) production, NK cytotoxicity and gene expression of cytokines related with macrophages and NK cell activity. Results and Conclusions : CME activated and promoted macrophage production of NO. It also enhanced gene expression of IL-1 and iNOS in RAW 264.7 cells. CME promoted cytotoxicity of NK cells against YAC-1 cells and enhanced NK cell related gene expression such as IL-1, IL-2, IL-12, iNOS, IFN-${\gamma}$ and　TNF-${\alpha}$ in mice splenocytes. It also Promoted protein expression of IL-10, IL-12, IFN-${\gamma}$ and TNF-${\alpha}$ in mice splenocytes and inhibited lung tumor metastasis induced by CT-26 cell line compared with the control group. From these results, it could be concluded that CME is an effective herbal drug for modulating the immune system and anti-cancer treatment by promoting macrophage and NK cell activity.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.12
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• pp.7179-7186
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• 2013

Background and Aims: Scutellaria is one of the most popular traditional Chinese herbal remedies against various human diseases, including cancer. In this study, we examined the active effects of Scutellaria extract and its main flavonoid constituents on the proportion of side population cells within human multiple myeloma cell line RPMI8226 in vitro and explored the potential molecular mechanisms involved. Materials and Methods: The contents of flavonoids in ethanolic extract of Scutellaria baicalensis Georgi were determined using high performance liquid chromatography. The antiproliferative effect of the ethanolic extract on RPMI-8226 was determined by CCK assay. Apoptosis was measured by annexin combining with propidium iodide in a flow cytometer. Cell cycle analysis was performed by propidium iodide staining in combination with flow cytometry analysis. Hoechst 33342 exclusion assay was used for the identification of side population within RPMI8226 cells. The expression of ABCG2 protein was assessed by Western blotting assay. Results: The content of major flavonoids constitutents of Scutellaria extract was baicalin (10.2%), wogonoside (2.50%), baicalein (2.29%), and wogonin (0.99%), respectively. The crude Scutellaria extract did not show significant anti-proliferative effect, apoptosis induction and cell cycle arrest in RPMI-8226 within the concentrations of $1-75{\mu}g/mL$. However, the ethanolic extract, baicalein, wogonin and baicalin reduced the side population cells in RPMI-8226, and data showed that baicalein and wogonin had stronger inhibitory effects. Correspondingly, they also exhibited significant effects on decreasing the expression level of ABCG2 protein in RPMI-8226 in vitro. Conclusions: Our results for the first time demonstrated a novel mechanism of action for Scutellaria extract and its main active flavonoids, namely targeting SP cells by modulating the expression of ABCG2 protein. This study provides an insight for new therapeutic strategies targeting cancer stem cells of multiple myeloma.

• Journal of Digital Convergence
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• v.15 no.10
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• pp.339-348
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• 2017

This study was conducted to examine the differences of anger expression style and cognitive characteristics among adolescents depending on the level of game addiction and game engagement. 420 high school boys were administered the Game Addiction/Engagement Scale, Behavioral Anger Response Questionnaire to measure anger expression style, and Irrational Belief Scale to measure cognitive characteristics. The results of correlation analyses showed that addiction had positive correlations with all the irrational belief factors and behavior anger factors except for assertion and avoidance. Engagement was positively correlated with all the variables except for direct anger-out, avoidance, and self-downing. Participants were divided into three groups depending on the level of addiction and engagement. Addiction high risk-low engagement group showed the lowest scores on support-seeking and the highest scores on diffusion and self-downing. Addiction high risk-high engagement group showed the highest scores on direct anger-out. Based on these findings, it was suggested that counselling strategies for adolescents at high risk of game addiction need to be varied depending on the level of game engagement.

• BMB Reports
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• v.51 no.10
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• pp.532-537
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• 2018

Prostaglandin $E_2$ ($PGE_2$), a major product of cyclooxygenase-2 (COX-2), plays an important role in the carcinogenesis of many solid tumors, including colorectal cancer. Because $PGE_2$ functions by signaling through $PGE_2$ receptors (EPs), which regulate tumor cell growth, invasion, and migration, there has been a growing amount of interest in the therapeutic potential of targeting EPs. In the present study, we investigated the role of EP4 on the effectiveness of cordycepin in inhibiting the migration and invasion of HCT116 human colorectal carcinoma cells. Our data indicate that cordycepin suppressed lipopolysaccharide (LPS)-enhanced cell migration and invasion through the inactivation of matrix metalloproteinase (MMP)-9 as well as the down-regulation of COX-2 expression and $PGE_2$ production. These events were shown to be associated with the inactivation of EP4 and activation of AMP-activated protein kinase (AMPK). Moreover, the EP4 antagonist AH23848 prevented LPS-induced MMP-9 expression and cell invasion in HCT116 cells. However, the AMPK inhibitor, compound C, as well as AMPK knockdown via siRNA, attenuated the cordycepin-induced inhibition of EP4 expression. Cordycepin treatment also reduced the activation of CREB. These findings indicate that cordycepin suppresses the migration and invasion of HCT116 cells through modulating EP4 expression and the AMPK-CREB signaling pathway. Therefore, cordycepin has the potential to serve as a potent anti-cancer agent in therapeutic strategies against colorectal cancer metastasis.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.32 no.1
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• pp.69-75
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• 2006

Head and neck squamous cell carcinoma(HNSCC) is the sixth most common cancer among men in the developed world affecting the tongue, pharynx, larynx and oral cavity. HNSCC is thought to represent a multistep process whereby carcinogen exposure leads to genetic instability in the tissue and accumulation of specific genetic events, which result in dysregulation of proliferation, differentiation, and cell loss and the acquisition of invasive capacity. Despite therapeutic and diagnostic progress in oncology during the past decades, the prognosis of HNSCC remains poor. Thus it seems that finding a biological tumor markers which will increase the early diagnosis and treatment monitoring rates, is of paramount importance in respect to improving prognosis. In an effort to identify gene expression signatures that may serve as biomarkers, this study several genes were selected, such as H3,3A, S100A7, UCHL1, GSTP1, PAI-2, PLK, TGF${\beta}$1 and bFGF, and used 7 HNSCC cell lines that were established various anatomical sites, and also 17 other cancer cell lines were used for control group using real-time quantitative RT-PCR and immunocytochemical analysis with a monoclonal antibody. In this study, S100A7 showed a clearly restricted occurrence in tongue originated cell line, and GSTP1 expression level in the pharynx originated cell line was very increased, relative to corresponding other cell lines. These results suggest that S100A7 and GSTP1 genes' expression can occur during tongue and pharynx originated head and neck tumorigenesis and that genetic change is an important driving force in the carcinogenesis process. This data indicate that S100A7 and GSTP1 expression pattern in HNSCC reflect both diagnostic clue and biological marker. And this is provides a foundation for the development of site-specific diagnostic strategies and treatments for HNSCC.

• (The) Korean Journal of Advertising
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• v.28 no.2
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• pp.7-25
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• 2017

The previous studies regarding prosocial behavior have been researched based on donors' personal traits and the effects of donees emotions. However, studies in identifying the effects of regulatory focus as motivational traits and the emotions resulting from donees' expression on prosocial behaviors have not been researched as much thoroughly. Specifically, consumers with prevention-focus perceive fit as the goal attainability process by avoiding negative factors. Thus, it is expected that the intentions of doing a charitable deed greater will more increase when the donees look sad than when they look happy. On the other hand, consumers with promotion-focus perceive fit as the consequential benefits of goal attainability when they are in the condition of a positive emotion. As a result, the intention of doing a charitable deed is expected to be increased greater when the donees have happier faces than sad faces. According to the experimental results, consumers with prevention focus more intended to do a charitable deed when the donees' expression was presented with a sad expression by mediating sadness. On the contrary, consumers with promotion focus show higher intention of doing a charitable deed when the donees looked happier by mediating happy feelings. This study has a theoretical meaningfulness in respect to expanding previous research concerning regulatory focus into donation contexts. Furthermore, this study has practical implications by presenting the donation strategies on information presentations of donees.

• Smart Media Journal
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• v.10 no.4
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• pp.91-101
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• 2021

Visual communication based on socio-cultural context, such as emoticons on social media, is increasing. Therefore, it is necessary to study the visual expression of metonymy as a means to correctly understand the communication method in the age of visual culture. The purpose of this study is to explore how metonymy is visualized within a cultural context. Specifically, , a typical underlying phenomenon of metonymy expression, and the expression principles of various reproduced through it are identified by pairing them with the cultural context. Based on context theory, which is a representative discourse in the social science field, emoticons from in high context and emoticons in in low context were selected and compared as case study subjects. The major findings are: First, a visual application model of metonymy was proposed regarding the process through which metonymy is reproduced as a visual result. Second, the types of metonymy and their salience attribute applied to the emoticon expression method was identified in detail. Third, based on the contextual theory, how the characteristics of high-context visual metonymy differ from that of low-context visual metonymy were presented. In the future, the results of this study can be used as a criterion for judging the local acceptability and local suitability of design results in the design development process that requires the use of localization strategies.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.2
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• pp.118-125
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• 2010

Background and Purpose: Bone metastases rarely occur in patients with oral squamous cell carcinoma (OSCC), so the molecular mechanisms of bone metastasis of OSCC remains unclear. Studies with animal models allow progresses in understanding the molecular events for bone metastasis and provide new targets for therapy. So we tried to establish a murine model for bone metastasis of oral squamous cell carcinoma. Materials and Methods: Human OSCC cells (KB cell line) were xenografted to nude mice via direct inoculation into the tibial marrow. Mice with tibial tumors were sacrificed once a week, until seven weeks after the injection of human tumor cells. Growth of tibial tumors were observed by histology. Expression of TGF-$\beta$ and CXCR-4 in bone OSCC (experimental) and subcutaneous tumor (control) was also evaluated by immunohistochemical staining. Results: Bone OSCC was successfully induced by intra-tibial injection of KB cells. Tumor mass was developed in the marrow tissues of tibia and finally invade the endosteum of tibia. Immunohistochemical staining showed higher expression of TGF-$\beta$ in bone tumors than in subcutaneous tumors. Conclusion: A murine model of bone metastasis of OSCC was suggested that imitated the clinical findings of distant vascular metastasis. This bone tumor model should facilitate understanding of the molecular pathogenesis of OSCC bone metastasis, and aid in the developement of treatment strategies against OSCC bone metastasis.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.161-168
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• 2015

Given social problems of social network service (SNS) addiction, it is critical to understand user's formation mechanism of SNS addiction. Since a number of studies have demonstrated the negative outcomes of excessive SNS use, the researchers examined important antecedents of SNS addiction as SNS habit that is considered as a key driver of SNS addiction. Moreover, the effects of self-expression, network management, and information search on SNS addition formation were investigated. The proposed theoretical model was empirically tested by using longitudinal survey data collected from 206 Facebook users. The analysis results indicate that SNS habit plays an important role in forming SNS addiction. Further, self-expression, network management, and information search influence SNS addiction through SNS habit. The analysis results offer some in-depth perspectives to SNS providers and government that establish policies or digital convergence strategies to induce healthy SNS use.