• IMMUNE NETWORK
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• 제2권1호
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• pp.53-59
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• 2002

Background: Clinical observations and laboratory studies have supported an immune basis for most acquired aplastic anemias, with the majority of patients responding to immunosuppressive therapy. Fas, a member of the tumor necrosis factor (TNF) receptor superfamily is a critical downregulator of cellular immune responses. Proinflammatory cytokines like interferon gamma (IFN-${\gamma}$) and TNF-${\alpha}$ can induce Fas expression and render hematopoietic progenitor cells susceptible to Fas-induced growth suppression and apoptosis. Methods: In order to investigate the involvement of apoptosis in the pathogenesis of aplastic anemia (AA), we measured the expression of Fas antigen and caspase-3 on bone marrow (BM) mononuclear cells (MNCs) of AA in the presence or absence of IFN-${\gamma}$, TNF-${\alpha}$, or macrophage inflammatory protein 1-${\alpha}$ (MIP-$1{\alpha}$). Results: We confirmed that AA BM MNCs were more apoptotic and highly expressed Fas antigen than normal donors. Stimulation by IFN-${\gamma}$, TNF-${\alpha}$, or MIP-$1{\alpha}$ increased Fas antigen and caspase-3 expression in AA BM MNCs than BM MNCs of normal donors. Anti-Fas monoclonal antibody enhanced IFN-${\gamma}$, TNF-${\alpha}$, or MIP$1{\alpha}$ mediated caspase-3 expression in BM MNCs of normal donors. Among these three cytokines, IFN-${\gamma}$ enhanced apoptosis most strongly via Fas-caspase-3 pathway. Conclusion: These results suggest that Fas signal pathway may play a role in the pathophysiology of aplastic anemia and negative hematopoietic regulators like IFN-${\gamma}$ can induce apoptosis of bone marrow progenitors in part by Fas induction.

• 무역학회지
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• 제44권3호
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• pp.271-287
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• 2019

This paper reviews and analyzes the ethical issues of multinational corporations (MNCs) in Africa. First, we find that the transparency and institutions of a host country have a negative relationship with the number of ethical violations of the MNCs. Second, this covers the effects of industry characteristics on each category of ethical issues such as the human rights and the environment. Based on the database of "Ethical Consumer", we show that the Auto, Chemical, Finance, and Telecommunication industries are more likely to violate human rights issues, and that Mining, Oil, Cosmetics, and Chemical industries are more likely to pollute the environments. Further, the country of origin does matter: the US and Asian companies are more likely to be involved with the business ethics violations than are their European counterparts.

• 국제지역연구
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• 제14권3호
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• pp.290-311
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• 2010

본 논문은 다국적기업 R&D랩들의 중국내 비즈니스활동이 활성화됨에 따라, 다국적기업이 중국에 어떤 진출동기로 어떤 유형의 R&D랩을 설립하는지에 대한 분석을 진행하고자하였다. 다국적기업 R&D랩의 중국진출동기를 중국의 시장이나 고객을 확보하기 위한 시장요인, 중국의 훌륭한 인적자원을 활용하기 위한 인적자원요인, 중국내 경쟁에서 경쟁우위를 차지하기 위한 경쟁우위요인과 정치적 환경요인 4가지로 분류하고, R&D랩 유형을 글로벌 기술센타, 현지 시장지원 랩, 현지 기술지원 랩 등 3가지 유형으로 분류하여 진출동기별 선택 가능한 R&D랩 유형을 규명하였다. 그 결과, 시장요인을 지향하거나 경쟁우위를 지향하는 다국적기업들은 현지 시장지원 랩을, 중국의 자원요인을 지향하는 다국적기업들은 글로벌 기술센터를 많이 설립하는 것으로 나타났다. 또한 중국의 감세, 면세 등 정책적 이점을 지향하여 R&D랩을 진출하는 다국적기업들은 현지 기술지원 랩을 선택하는 경우가 많았다.

• 마케팅과학연구
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• 제18권4호
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• pp.277-306
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• 2008

Knowledge1 is considered to be a key element of understanding how organizations gain and sustain competitive advantages. But very few firms are capable of creating the requisite knowledge and thus, firms should acquire and exploit new knowledge through knowledge transfer processes. The empirical part of this study involves examining relationships among adaptability of knowledge and knowledge transfer and marketing performance and testing the moderating roles of absorptive capacity, socialization and local marketing knowledge. This study is organized as follows: (1) Previous literature on knowledge, knowledge transfer and absorptive capacity is summarized, followed by the development of hypotheses derived from the knowledge-based view and absorptive capacity. (2) The hypotheses are tested with data collected from MNCs' subsidiaries performing marketing activities in Korea.Thestudyisclosedwithfindings,implications,andconclusions. Following six research hypotheses are drawn from literature review in related areas: H1: Adaptability of knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with knowledge inflows into the receiving subsidiary. H2: The level of marketing knowledge transferred from the MNCs' headquarters and other subsidiaries is positively associated with marketing performance of the receiving subsidiary. H3: Increases in potential absorptive capacity will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H4: Increases in realized absorptive capacity will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. H5: Increases in socialization activity among the headquarters and subsidiaries will enhance the relationship between adaptability of knowledge and the level of marketing knowledge transfer. H6: Increases in the level of locally developed marketing knowledge will enhance the relationship between the level of knowledge transfer and marketing performance of the receiving subsidiary. The research framework that illustrates the proposed hypotheses is presented in figure 1. The unit of analysis for this study is knowledge transfer from the MNCs' headquarters and other subsidiaries to their subsidiaries operating in South Korea. The population for this study consists of subsidiaries established either as joint ventures or as wholly-owned subsidiaries. A group of 603 foreign firms were drawn from diverse industry organizations and business societies. After personal contact, telephone, fax, and e-mail to request that the respondents complete the questionnaire, 282 valid questionnaires from 133 initial sample companies were collected. The results of the empirical analyses significantly support all of the proposed hypotheses except hypothesis 3. Adaptability of external knowledge promotes knowledge transfer and the relationship is moderated by a firm's potential knowledge absorptive capacity. On the other hand, knowledge transfer improves a firm's marketing performance and a firm's realized knowledge absorptive capacity and local marketing knowledge moderate the relationship. The theoretical and practical implications of the findings in this study are as follows: (1) firms must take seeking, transferring, sharing and exploiting of external knowledge into serious consideration, while simultaneously creating knowledge to support the necessary business operations, remain competitive, and achieve superior performance. (2) Firms should continuously seek to develop their knowledge absorptive capacity (both potential and realized capacity) to absorb, learn and utilize valuable external knowledge. (3) Firms should emphasize not only absorptive capacity, but also development of local knowledge. Firms with strong absorptive capability and local knowledge can learn and transfer more external knowledge, which can be translated into greater levels of competence and performance.

• The Korean Journal of Physiology and Pharmacology
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• 제20권4호
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• pp.425-432
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• 2016

In addition to classical synaptic transmission, information is transmitted between cells via the activation of extrasynaptic receptors that generate persistent tonic current in the brain. While growing evidence supports the presence of tonic NMDA current ($I_{NMDA}$) generated by extrasynaptic NMDA receptors (eNMDARs), the functional significance of tonic $I_{NMDA}$ in various brain regions remains poorly understood. Here, we demonstrate that activation of eNMDARs that generate INMDA facilitates the ${\alpha}$-amino-3-hydroxy-5-methylisoxazole-4-proprionate receptor (AMPAR)-mediated steady-state current in supraoptic nucleus (SON) magnocellular neurosecretory cells (MNCs). In $low-Mg^{2+}$ artificial cerebrospinal fluid (aCSF), glutamate induced an inward shift in $I_{holding}$ ($I_{GLU}$) at a holding potential ($V_{holding}$) of -70 mV which was partly blocked by an AMPAR antagonist, NBQX. NBQX-sensitive $I_{GLU}$ was observed even in normal aCSF at $V_{holding}$ of -40 mV or -20 mV. $I_{GLU}$ was completely abolished by pretreatment with an NMDAR blocker, AP5, under all tested conditions. AMPA induced a reproducible inward shift in $I_{holding}$ ($I_{AMPA}$) in SON MNCs. Pretreatment with AP5 attenuated $I_{AMPA}$ amplitudes to ~60% of the control levels in $low-Mg^{2+}$ aCSF, but not in normal aCSF at $V_{holding}$ of -70 mV. $I_{AMPA}$ attenuation by AP5 was also prominent in normal aCSF at depolarized holding potentials. Memantine, an eNMDAR blocker, mimicked the AP5-induced $I_{AMPA}$ attenuation in SON MNCs. Finally, chronic dehydration did not affect $I_{AMPA}$ attenuation by AP5 in the neurons. These results suggest that tonic $I_{NMDA}$, mediated by eNMDAR, facilitates AMPAR function, changing the postsynaptic response to its agonists in normal and osmotically challenged SON MNCs.

• 과학기술정책
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• 제1권9호통권9호
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• pp.3-9
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• 1991

이 글은 당 연구소 주관으로 열린 「새로운 국제 기술 질서의 태동과 한국 과학 기술의 진로」라는 주제의 국제 심포지움에서 행한 Denis F. Simon 박사(미국 터프트 대학 교수)의 강연 내용을 요약, 편집한 것이다.

• International Journal of Quality Innovation
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• 제10권2호
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• pp.43-56
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• 2009

Many companies are trying to acquire innovative technologies and relevant knowledge by sending R&D work overseas. Although recent research has been focusing on the aspects that motivate MNCs to establish offshore R&D facilities, such as cost reduction and market expansion, little is known about external or circumstantial factors influencing the performance of global R&D activities. Searching for enhancers of offshore R&D facilities, we investigated the relationships between the performance of offshore R&D and the technological capabilities of a parent company, its home country, and its R&D hosting country. Both patent data of ED and the ED R&D scoreboard of 134 overseas R&D labs from 46 MNCs, dating from the period of 2003 to 2005, are used in the analysis. The same time period is applied in calculating the RTA of each country. Regression analysis results support our main hypothesis that the technological capabilities of the parent company and the hosting country positively affect the performance of overseas R&D.

• 대한한방부인과학회지
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• 제30권4호
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• pp.1-17
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• 2017

Objectives: This study was conducted to evaluate the effects of Hyeolbuchugeo-tang (HBC) on Osteoporosis. Methods: We induced RAW 264.7 cells to differentiate to Osteoclasts by RANKL and treated RANKL-induced RAW 264.7 cells with HBC (0, 150, 350, $700{\mu}g/ml$). To measure osteoclast differentiation and activation, we counted TRAP (+) MNCs and measured mRNA expressions of its related genes (TRAP, MMP-9, cathepsin K, NFATc1, c-Fos, MITF, iNOS, COX-2, TNF-${\alpha}$) by RT-PCR. To assess bone resorption, the Bone pit formation were examined under a microscope. Results: HBC decreased TRAP (+) MNCs and inhibited mRNA expressions of TRAP, MMP-9, cathepsin K, NFATc1, c-Fos, MITF in osteoclast. And HBC inhibited Bone pit formation. Conclusions: HBC inhibited osteoclast differentiation and activation and bone resorption. Taken together, these results indicate that HBC might have potentials for prevention and treatment of Osteoporosis.

• Natural Product Sciences
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• 제22권2호
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• pp.87-92
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• 2016

Endothelial dysfunction in atherosclerosis is associated with increasing oxidative stress that could be reversed by antioxidant. Therefore epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC) and catechin (C) of tea flavonoids were investigated for their roles in regenerating endothelial cell. Peripheral blood mononuclear cells (PB-MNCs) were isolated, plated and cultured in medium with/without treatment of EGCG, ECG, EGC and C. Results showed that among all EGCG, ECG, EGC and C concentrations tested, $12.5{\mu}mol/L$ was not cytotoxic for peripheral blood-derived endothelial progenitor cells (PB-EPCs). Treatment of EGCG, ECG, EGC or C increased the percentages of CD34, CD133, VEGFR-2 expressions and suppressed hydrogen peroxide-induced percentages of reactive oxygen species (ROS) level in PB-EPCs. Taken together, our current results showed that EGCG, ECG, EGC or C of tea flavonoids could induce differentiation of PB-MNCs into PB-EPCs as well as protect PB-EPCs from oxidative damage by suppresing the intracellular ROS levels.

• 대한치과교정학회지
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• 제25권6호
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• pp.715-722
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• 1995

Orthodontic tooth movement in response to orthodontic force results from actions of osteoclasts and osteeoblasts in the cell level. Convincing evidence has now been provided to support the view that osteoclasts are derived from mononuclear cells that originate in the bone marrow or other hematopoietic organs and they migrate to the bones via vascular routes. Nitric oxide(NO), which accounts for the biological properties of endothelium-derived relaxing factor(EDRF), is the endogenous stimulator of soluble guanylate cylase. The discovery of the formation of nitric oxide(NO) from L-arginine in mammalian tissues and its biological roles has, in the last 7 years, thrown new light onto many areas of research. Data from experiments in vitro showed that N-metyl-L-arginine(L-NMA) and L-nitro-L- arginine(L-NAME) are competitive inhibitors of nitric oxide synthase. This study suggest that the multinucleated cells in our culture have characteristics of osteoclasts and that the potential bone cell activity of nitric oxide in vitro may be mediated in part by stimulation of marrow mononuclear cells to form osteoclast-like cells. Bone marrow cells were obtaineed from tibia of 19-days old chick embryo. After sacrifice, tibia was quickly dissected and the bone were then split to expose the medullary bone. The cells were attached for 4 hours and the nonadherent cells were collected. Marrow cells weere cultured in 96-well plate in medium 199. To examine the number of TRAP-positive multinucleated cells(MNCs), $10^{-8}\;M\;Vit=D_3$ and various concentration of L-NMA and L-NAME weere added at the beginning of cultures and with each medium change. After 7 days of culture. tartrate-resistant acid phosphatase(TRAP) staining was performed for microscopic evaluation. Cells haying more than three nuclei per cell were counted as MNCs. The obsrved results were as follows;1. 1,25-dihydroxyvitamine $D_3$ stimulated the osteoclast-like multinucleated cells in cultures of chick embryo bone marrow. 2. Nitric oxide synthase inhibitors(NOSI ; N-NMA, N-NAME) stimulated the osteoclast-like cells in cultures of chick embry bone marrow. 3. 1,25-dihydroxyvitamine$D_3$ and nitric oxide synthase inhibitors did not appear to have additive effect on the generation of TRAP-positive MNCs. These results suggest that nitric oxide synthase inhibitors may stimulate the osteoclast-like multinucleated cell formation and fusion in cultures of chick bone marrow.