• Archives of Pharmacal Research
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• v.22 no.3
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• pp.232-236
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• 1999

In this study, we present evidence that cotreatment of aloesin and arbutin inhibits tyrosinase activity in a synergistic manner by acting through a different action mechanism. Aloesin or arbutin similarly inhibited enzyme activity of human- and mushroom-tyrosinases with an IC50 value of 0.1 or 0.04 mM, respectively. Lineweaver-Burk plots of the enzyme kinetics data showed that aloesin inhibited tyrosinase activity noncompetitively with a Ki value of 5.3 mM, whereas arbutin did it competitively (Maeda, 1996). We then examined whether cotreatment of these agents inhibits the tyrosinase activity in a synergistic manner. The results showed that 0.01 mM aloesin in the presence of 0.03 mM arbutin inhibited activity of mushroom by 80% of the control value and the reverse was also true. The inhibitory effects were calculated to be synergistic according to the B rgi method. Taken together, we suggest that aloesin along with arbutin inhibits in synergy melanin production by combined mechanisms of noncompetitive and competitive inhibitions of tyrosinase activity.

• The Journal of Information Systems
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• v.28 no.3
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• pp.59-81
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• 2019

Purpose The purpose of this study is to investigate the resistance factors interfering the acceptance factors of the mobile easy remittance service focusing on the switching cost and the innovation resistance model. Design/methodology/approach This study focuses on revealing the resistance factors of the mobile easy remittance service acceptance. The resistance factor is designed consisting both consumer characteristics and service characteristics in the Innovation Resistance Model. Furthermore, the effect of resistance factors on the innovation resistance and acceptance intentions were detected by moderating the switching cost. Findings According to the empirical analysis result, this study investigated the effect of resistance factors on innovation resistance and acceptance intention for the mobile easy remittance service. The results of this study as follows; (1) The consumer's inherent innovativeness did not significantly affect the innovation resistance and acceptance intention. (2) The attitude toward existing services and complexity significantly affected innovation resistance in direct manner, thus affecting the acceptance intention in indirect manner. (3) The perceived usefulness significantly affected both the innovation resistance and the acceptance intention in direct manner. (4) The perceived risk only effected the acceptance intention. (5) The switching cost had a moderating effect on the innovation resistance and acceptance intention.

• Journal of Periodontal and Implant Science
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• v.30 no.2
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• pp.347-360
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• 2000

Bone remodeling results from the combined process of bone resorption and new bone formation which is regulated in part by some of the polypeptide growth factors such as platelet derived growth factor(PDGF), which has been known to be an important local regulator of bone cell activity and participate in normal bone remodeling. This process includes strictly regulated gene expression of several bone matrix proteins such as type I collagen and osteopontin, a 44 kDa phosphorylated glycoprotein, which has important roles in bone formation. The purpose of this study is to evaluate the effecs of PDGF-BB on the mRNA expression of bone matrix protein, type I collagen and osteopontin, in MC3T3- E1 cell culture. Cells were seeded at $5{\times}10^5$ cells in 10 ml of minimum essential medium alpha(${\alpha}-MEM$) containig 10% fetal bovine serum, 10 mM beta glycerophosphate. 0.1, 1, 10 ng/ml PDGF-BB were added to the cells for the day 3, 7, 14, 21, 28 and cultured for 24 hours. Type I collagen cDNA, Hf677, and osteopontin cDNA were used as probes for northern blot analysis. Total cellular RNA was purified at indicated day and northern blot analysis was performed. The results were as follows : Type I collagen mRNA expressions were higher at the day 3 and 7, and lower in the day 14, 21 in the control groups. In the experimental groups, mRNA expressions were increased when 0.1 ng/ml PDGF-BB were added on the day 3, 7, 21, and decreased in dose-dependent manner on the day 14, decreased at all added dose on the day 28. Osteopontin mRNA expressions were highest in the day 21 groups and lowest in the day 14 groups in the control groups. Interesting results were shown in the day 14 and 21 groups. We found that osteopontin mRNA level was increased in dose dependent manner in the day 14 groups, and decreased dose dependent manner in the day 21 groups. In conclusion, PDGF-BB may have various control effects on type I mRNA expression in the growth and differentiation process of MC3T3-E1 cells and may have contrary regulatory effects on osteopontin mRNA expression. For examples, when the baseline level of osteopontin mRNA was low, as in the day 14, PDGF-BB up-regulated osteopontin mRNA expression in dose dependent manner, and when the baseline level was high as in the day 21, PDGF-BB down-regulated dose dependent manner. Thus, it may be useful for clinical application in periodontal regeneration procedure if further study were performed.

• Bulletin of the Korean Chemical Society
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• v.33 no.8
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• pp.2756-2758
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• 2012

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2781-2784
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• 2007

Early detection of a disease is important to tackle treatment issues in a better manner. Several diagnostic techniques are in use, these days; for such purpose and tremendous research is going on to develop newer and newer methods. However, more work is required to be done to develop cheap and reliable early detection techniques. Micro-fluidic chips are also playing key role to deliver new devices for better health care. The present study focuses on a review of recent developments in the interrogation of different techniques and present state-of-the-art of microfluidic sensor for better, quick, easy, rapid, early, inexpensive and portable POCT (Point of Care testing device) device for a particular study, in this case, bone disease called osteoporosis. Some simulations of the microchip are also made to enable feasibility of the development of a blood-chip-based system. The proposed device will assist in early detection of diseases in an effective and successful manner.

• Toxicological Research
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• v.32 no.3
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• pp.239-243
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• 2016

Propolis is a multicomponent, active, complex resinous substance collected by honeybees from a variety of plant sources. We have studied the effect of propolis on neurite outgrowth of SH-SY5Y human neuroblastoma cells induced to differentiate by all-trans-retinoic acid (RA). Propolis, at a concentration of $3{\mu}g/mL$, had no significant effect on the viability of differentiating SH-SY5Y cells. However, the neurite outgrowth of the differentiating SH-SY5Y cells treated with propolis ($0.3{\sim}3{\mu}g/mL$) for 48 hr was significantly inhibited in a dose-dependent manner. Treatment of RA-stimulated differentiating SH-SY5Y cells with 0.3 to $3{\mu}g/mL$ propolis resulted in decreased level of transglutaminase and 43-kDa growth-associated protein (GAP-43) in a dose-dependent manner. The results indicate that propolis is able to inhibit neurite outgrowth of differentiating SH-SY5Y cells.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.18 no.2
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• pp.247-257
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• 2011

Purpose: This study was conducted to identify communication principles for nurses in cancer units according to Grice's theory. Method: This study was a secondary analysis of qualitative research using conversational analysis. Results: The principles consisted of four maxims: Quality, quantity, relevance and manner and 14 strategies. For the quality maxim, 'asking what you believe to be true' and 'saying the facts you know' strategies were identified. In the quantity maxim, the strategies were 'asking single questions', 'asking open questions' and 'asking optimistic questions'. In the relevance maxim, 'asking about the same theme' and 'giving relevant explanations' strategies were identified. In manner maxim, the strategies were 'using clear expressions in asking questions', 'asking in an orderly way', 'verifying answers', 'using clear expressions in explanations', 'explaining in an orderly way' and 'verifying understanding'. Conclusion: It is expected that these strategies will help and increase the degree of cooperation for nurses in effectively communication with cancer patients.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.3
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• pp.119-123
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• 2011

Carbon nanotilaments (CNFs) could be synthesized on nickel catalyst layer-deposited silicon oxide substrate using $C_2H_2$ and$H_2$ as source gases under thermal chemical vapor deposition system. By the incorporation of $SF_6$ as a cyclic modulation manner, the geometries of carbon coils-related materials, such as nano-sized coil and wave-like nano-sized coil could be observed on the substrate. The characteristics (formation density and morphology) of as-grown CNFs with or without $SF_6$ incorporation were investigated. Diameter size reduction for the individual CNFs-related shape and the enhancement of the formation density of CNFs-related material could be achieved by the incorporation of $SF_6$ as a cyclic modulation manner. The cause for these results was discussed in association with the slightly increased etching ability by $SF_6$ addition and the sulfur role in SF 6 for the geometry change.

• Environmental Mutagens and Carcinogens
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• v.21 no.2
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• pp.135-141
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• 2001

Endocrine disruptors have been implicated in carcinogenesis in animal studies, but carcinogenetic effects on human remain controversial. In order to examine the genotoxicity of two common endocrine disruptors, Bisphenol A and Diethylstilbestrol, cytogenetic endpoints including chromosome aberration (CA), sister chromatid exchange (SCE), micronuclei (MN) analyses and DNA damage by single cell gel electrophoresis (SCGE) were assessed. The effects of Bisphenol A and Diethylstilbestrol on the frequencies of CA and MN were increased in a dose-dependent manner and that of Bispheol A was more significant by Kendall'$\tau$test. Bisphenol A and Diethylstilbestrol also increased the frequency of SCE. Bisphenol A and Diethylstilbestrol induced DNA damage in a dose-dependent manner and the DNA damage induced by Diethylstilbestrol in human blood lymphocytes was more significant.

• Biomedical Science Letters
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• v.13 no.2
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• pp.99-104
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• 2007

To determine whether 17$\beta$-estradiol induces the morphological changes in adipose and liver tissues, we measured the effects of 17$\beta$-estradiol on adipose tissue mass, adipocyte histology and hepatic lipid accumulation in female ovariectomized (OVX) C57BL/6J mice. Compared to vehicle-treated control mice, 17$\beta$-estradiol-treated mice decreased adipose tissue mass and the size of adipocytes, and concomitantly increased the number of adipocytes in a dose-dependent manner. In addition, the administration of 17$\beta$-estradiol resulted in reduced hepatic lipid accumulation in a dose-dependent manner. These results suggest that estrogen may regulate adipocyte development and lipid metabolism in female OVX C57BL/6J mice.