• Survey Research
• /
• v.1 no.2
• /
• pp.59-87
• /
• 2000

The hypothesis of this study is that change acceptance and work adaptation of change agents are influenced by positive self-image and risk tolerance. In order to examine the hypothesis, this study was performed with 305 change agents from six branches of a conglomerate company. Specifically, self-image was measured by locus of control, self-efficacy, self-esteem, and positive affectivity; risk tolerance was measured by tolerance for ambiguity, risk aversion, and openness to experience. The result of this study indicated that self-image and risk tolerance significantly predicted change acceptance and work adaptation. Especially, the results of structural model revealed that change acceptance mediated the relationship between characteristic variables (such as self image and risk tolerance in this study) and work adaptation. Based on the results, we suggest that change agents keep developing positive self-image and risk tolerance in order to play the key role in leading organizational change.

• KIPS Transactions on Software and Data Engineering
• /
• v.3 no.5
• /
• pp.169-178
• /
• 2014

In this paper, we present a research utilizing decentralized LTL specifications for ensuring a quality for interaction-centralized system. In this system, for ensuring the quality, we need to validate interactions between modules of the system and then we should check whether the system achieves the expected requirements. This task remains difficult and labor-intensive and requires an expert. In this paper, we present a method to assist such a task. First of all, the requirements of the system is written as multiple LTL specifications. Interactions between modules mean that behaviors of one module are related with other one's behavior. We generate the automaton model fully achieving specification through GR(1) synthesis. And we simulate them using the simulator based on the software agent for checking behaviors of the system. Finally, we validate the whole system whether it achieves given requirements.

• BMB Reports
• /
• v.37 no.2
• /
• pp.239-245
• /
• 2004

We have previously demonstrated that the redox reactant pyruvate prevents apoptosis in the oxidant model of bovine pulmonary artery endothelial cells (BPAEC), and that the anti-apoptotic mechanism of pyruvate is mediated in part via the mitochondrial matrix compartment. However, cytosolic mechanisms for the cytoprotective feature of pyruvate remain to be elucidated. This study investigated the pyruvate protection against endothelial cytotoxicity when the glycolysis inhibitor 2-deoxy-D-glucose (2DG) was applied to BPAEC. Millimolar 2DG blocked the cellular glucose uptake in a concentration- and time-dependent manner with >85% inhibition at $\geq$5 mM within 24 h. The addition of 2DG evoked BPAEC cytotoxicity with a substantial increase in lipid peroxidation and a marked decrease in intracellular total glutathione. Exogenous pyruvate partially prevented the 2DG-induced cell damage with increasing viability of BPAEC by 25-30%, and the total glutathione was also modestly increased. In contrast, 10 mM L-lactate, as a cytosolic reductant, had no effect on the cytotoxicity and lipid peroxidation that are evoked by 2DG. These results suggest that 2DG toxicity may be a consequence of the diminished potential of glutathione antioxidant, which was partially restored by exogenous pyruvate but not L-lactate. Therefore, pyruvate qualifies as a cytoprotective agent for strategies that attenuate the metabolic dysfunction of the endothelium, and cellular glucose oxidation is required for the functioning of the cytosolic glutathione/NADPH redox system.

• Journal of Ginseng Research
• /
• v.39 no.4
• /
• pp.304-313
• /
• 2015

Background: Ginsenoside Rg3 is a promising anticancer agent. It is usually produced by heat treatment of ginseng, in which ginsenoside Rb1 is the major ginsenoside. A kinetic study was conducted to optimize ginsenoside Rg3 production by the heat treatment of ginsenoside Rb1. Methods: Ginsenoside Rb1 was heated using an isothermal machine at $80^{\circ}C$ and $100^{\circ}C$ and analyzed using HPLC. The kinetic parameters were calculated from the experimental results. The activation energy was estimated and used to simulate the process. The optimized parameters of ginsenoside Rg3 production are suggested based on the simulation. Results: The rate constants were $0.013h^{-1}$ and $0.073h^{-1}$ for the degradation of ginsenosides Rb1 and Rg3 at $80^{\circ}C$, respectively. The corresponding rate constants at $100^{\circ}C$ were $0.045h^{-1}$ and $0.155h^{-1}$. The estimated activation energies of degradation of ginsenosides Rb1 and Rg3 were 69.2 kJ/mol and 40.9 kJ/mol, respectively. The rate constants at different temperatures were evaluated using the estimated activation energies, and the kinetic profiles of ginsenosides Rb1 and Rg3 at each temperature were simulated based on the proposed kinetic model of consecutive reaction. The optimum strategies for producing ginsenoside Rg3 from ginsenoside Rb1 are suggested based on the simulation. With increased temperature, a high concentration of ginsenoside Rg3 is formed rapidly. However, the concentration decreases quickly after the reaching the maximal concentration value. Conclusion: The optimum temperature for producing ginsenoside Rg3 should be the highest temperature technically feasible below $180^{\circ}C$, in consideration of the cooling time. The optimum reaction time for heat treatment is 30 min.

• YAKHAK HOEJI
• /
• v.59 no.6
• /
• pp.259-265
• /
• 2015

In recent, there are increasing reports about pharmacological activities of Crataegi Fructus which has been used for many centuries as medicinal and food sources in East Asia. However, its antifungal efficacy needs to be investigated. Thus, in the current study, we determined synergistic antifungal activity of the Crataegi Fructus extract (CFE) when combined with fluconazole (FLC) against disseminated candidiasis due to Candida albicans. This fungus is one of the most problematic fungal pathogens. Data resulting from a microdilution susceptibility test showed that CFE had a dose-dependent antifungal activity. When the extract was combined with FLC, the activity was synergistic. For example, the antifungal activity by the combination of CFE at $20{\mu}g/ml$ plus FLC at $0.1{\mu}g/ml$ was 4 times more effective than antifungal activity by FLC alone at the same concentration (P<0.05). In the murine model of disseminated candidiasis, the combination therapy potentiated resistance of mice, resulting in 80% of C. albicans-infected animals surviving the entire period of 40 days observation, whereas mice given CFE alone or FLC alone all died with 17 and 23 days, respectively, although they survived longer than the untreated control animals (P<0.05). The CFE's antifungal activity seemed to be related to the blockage of hyphal production of C. albicans yeast cells. In summary, CFE has a synergistic antifungal activity, which can be produced by combining CFE with FLC. Thus, our data strongly indicate that CFE may be a potential candidate as an antifungal agent for combination therapy.

• YAKHAK HOEJI
• /
• v.56 no.1
• /
• pp.20-25
• /
• 2012

In Northeast Asia, Paeoniae Radix has been used in treatments of inflammation-causing diseases such as arthritis for many centuries. Paeoniflorin, one of the principle bioactive monoterpene glucosides from the paeony root, is reported to be mostly responsible for the effectiveness of the treatments. However, the anti-inflammatory effect of a monoterpene, paeoniflorigenone (PFG) which partially has the moiety of paeoniflorin minus a glucose structure is unknown. Thus, the aim of this work was to investigate anti-inflammatory activity of PFG. For the investigation, PFG activity on the NO (nitric oxide) production from LPS-stimulated macrophages, and the anti-inflammatory effect was tested in the animal model of septic arthritis caused by Candida albicans, a major etiological agent for septic arthritis. For induction of the arthritis, mice were administered with an emulsion of C. albicans cell wall (CACW) mixed with Complete Freund's Adjuvant (CFA) via footpad-injection (Day 0); PFG at a dose of 0.5 or 1 mg/mouse (25 or 50 mg/kg of body-weight) was given to the animals on Day 3, 6, and 9; footpads were scored for arthritis. Moreover, the PFG effect on proliferation of T-lymphocyte that causes aggravation of arthritis was additionally tested. Data resulting from those tests showed that PFG inhibited the NO production from the stimulated macrophage in a dose dependent manner (P<0.05), indicating that PFG is an anti-inflammatory. To confirm the in-vitro results, anti-inflammatory activity of PFG was determined against C. albicans-caused septic arthritis. Data showed that PFG-treatment reduced footpad-swelling which indicates that PFG has anti-arthritic effect (P<0.05), which is therapeutic. The anti-arthritic effect appeared to be mediated by PFG suppression of T-cell proliferation. Ultimately, PFG, a monoterpene component, has anti-inflammatory activity analogous to paeoniflorin. The anti-inflammatory activity treats the septic arthritis due to a pathogenic fungus C. albicans.

• YAKHAK HOEJI
• /
• v.52 no.5
• /
• pp.402-406
• /
• 2008

Previously, we have shown that 1-furan-2-yl-3-pyridin-2-yl-propenone (FPP-3) has an anti-inflammatory activity in a rat paw-edema model. In the present study, we investigated an inhibitory effect of FPP-3 on the tumor necrosis factor (TNF)-${\apha}$-induced inflammatory cytokine response in HT-29 human colon epithelial cells. Treatment with FPP-3 significantly prevented the TNF-${\apha}$-induced attachment of leukocytes to HT-29 colon epithelial cells, which is one of the pathologic hallmarks in colon inflammation. The effect of FPP-3 was markedly superior than that of 5-aminosalicylic acid (5-ASA), a commonly used drug for the treatment of inflammatory bowel disease (IBD). The pretreatment with FPP-3 inhibited TNF-${\apha}$- induced monocyte chemoattractant protein (MCP)-1, interleukin (IL)-8 mRNA expressions. In addition, FPP-3 significantly suppressed TNF-${\apha}$-induced nuclear factor (NF)-${\kappa}B$ transcription activity. These results demonstrate that FPP-3 modulates intestinal inflammation via suppressing the NF-${\kappa}B$ dependent expressions of MCP-1 and IL-8, and suggest that FPP-3 may be a valuable agent for the treatment of IBD.

• Archives of Pharmacal Research
• /
• v.29 no.5
• /
• pp.348-353
• /
• 2006

In this study, a 40% ethanol extract of Chinese yam flour (Dioscoreae rhizoma), containing $177{\pm}58{\mu}g/mL$ of dioscin, was tested in order to evaluate its pharmacological effects on the gastrointestinal tracts of Sprague-Dawley rats. Via the ingestion of the Chinese yam extract, the secretion of gastric acid was suppressed in the rats, and gastrointestinal motility increased by as much as 10%. The fecal quantity of rats fed on the Chinese yam extract also increased, by more than 40% as compared with that of the controls. The Chinese yam extract was found not to affect the growth of normal intestinal bacteria. However, a great deal of lactose-fermenting bacteria was observed in the fecal samples of rats fed for 6 weeks on 2% Chinese yam extract. This finding would appear to suggest that Chinese yam extract not only induces an improvement in digestive capability, but also affects the conversion of some intestinal flora to helpful bacteria. Our serochemical analyses indicated that serum glucose, neutral lipid, and total cholesterol levels were reduced to some degree by long-term feeding on Chinese yam extract. This finding bolsters the notion that Chinese yam extract may prove helpful as a digestion-aiding agent for patients suffering from hyperglycemia or hyperlipidemia.

• The Journal of Information Systems
• /
• v.19 no.2
• /
• pp.37-71
• /
• 2010

This article identifies factors affecting successful ERP systems by focusing on the stages after stabilizing ERP systems and overcoming temporary performance dip by introduction of ERP systems, and suggests change management tactics to control those identified factors. We can not expect that every users are familiar with the usage of an ERP system even after they are informed about the expected advantage of the newly implemented ERP system and trained intensively for changed business process and system usage while implementing a new ERP system. Moreover, even after more than six months usage of the system, the users may still have some trouble due to the reason why they have insufficient information about the expected advantage of the system (recognition gap) and insufficient knowledge about the changed usage of the system (knowledge gap). Hence, this article diagnoses by conducting a case study that those recognition and knowledge gap would have a severe bad influence upon the users' trust and satisfaction on ERP systems. This article suggests an appropriate change management tactics to overcome those recognition and knowledge gap by considering the relationship with the efforts for change management before, during, and after the introduction of ERP systems and performing an in-depth analysis on the users' dissatisfaction and request for update during the stages after the stabilization of the ERP systems. This article also shows a corroborative evidence that these efforts of change management consequently contributes to the solution of users' distrust and dissatisfaction. In sum, this article identifies the factors influencing badly on the magnitude and seriousness of knowledge and recognition gap, and suggests a conceptual research model which says that the satisfaction of ERP users could be uplifted by the solution of their knowledge and recognition gap if we keep making efforts on appropriate change management considering those identified factors during the stages after the stabilization of an ERP system.

• Journal of Acupuncture Research
• /
• v.22 no.2
• /
• pp.171-180
• /
• 2005

Background & Objective : Angiogenesis consists of the proliferation, migration, and differentiation of endothelial cells, and angiogenic factors and matrix protein interactions modulate this process. The aim of this study was to determine whether Puerariae radix could induce angiogenic activity in human umbilical vein endothelial cells (HUVECs). Methods: The angiogenic activity of Puerariae radix were evaluated by using BrdU assay, chemotactic migration assay, tube formation assay, measurement of bFGF in HUVECs, and Matrigel plug assay in mice. Results : Puerariae radix significantly increased HUVECs proliferation in a dose-dependent manner. In addition, Puerariae radix increased migration and tube-like formation in HUVECs. Interestingly,the expression of basic fibroblast growth factor (bFGF), an angiogenesis-stimulating growth factor, was dose-dependently increased by Puerariae radix. The angiogenic activity of Puerariae radix was confirmed using an in vivo Matrigel angiogenesis model, showing promotion of blood vessel formation. Conclusion : Puerariae radix significantly induces angiogenesis in vitro and in vivo. These results suggest that Puerariae radix is a potent angiogenic agent, and a promising drug, for the induction of neovascularization.