• Korean Journal of Optics and Photonics
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• v.20 no.1
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• pp.53-56
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• 2009

We applied an ellipsometric technique to get quantitative information about the thickness and refractive index of human Mesenchymal Stem Cells (hMSCs). The images of ellipsometric constants $\Delta$, $\Psi$ for the nucleus region and for the cell body region of hMSCs were obtained by using an Imaging Ellipsomter (IE) for their in vitro state. A numerical inversion method was applied to deduce the refractive index and the thickness of hMSCs from the measured $\Delta$, $\Psi$. Thus the images of the refractive index and those of the thickness of hMSCs for the nucleus region and for the cell body region are reported.

• Korean Journal of Plant Tissue Culture
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• v.25 no.3
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• pp.153-158
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• 1998

The internal structures of Arabidopsis thaliana infected with beet curly top virus (BCTV) were studied by light microscopy. Hyperplasia was observed in the inflorescence stems of Arabidopsis thaliana ecotype Sei-O at 2 weeks after BCTV-Logan inoculation and callus was induced on symptomatic tissues at 4 weeks after virus inoculation. The infection processes were revealed as follows: hyperplasia of phloem tissue, necrosis of hyperplastic phloems, lacuna formation of necrotic tissues, elongation and enlargement of cortex and epidermal cells surrounding the lacuna formed phloem tissues, induction of cell division in the enlarged cortex and epidermal cells, and induction of callus tissue. Callus formation on Arabidopsis was caused by the virus infection, and virus inclusion body was observed in both phloem and callus tissue by azure-A staining.

• Journal of the korean academy of Pediatric Dentistry
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• v.43 no.4
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• pp.419-426
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• 2016

For this research 20 supernumerary teeth impacted in the maxillary anterior have been extracted and pulp cells have been collected from them. From the collected pulp cells, total of 17 (10 males, 7 females) have been selected as subjects. From this research, the run-time of successive culture of the cell from tooth number pulp tissue was $2.91{\pm}0.29$ days. From the gathering of cells from the initial pulp tissue until gaining 80% confluency took $4.53{\pm}0.94$ which was the longest. The following successive cultures took $2.73{\pm}0.32$ days. Average runtime for female was $2.81{\pm}0.27$ days whereas male had average runtime of $2.98{\pm}0.29$ days. Average run-time for inversion was $2.94{\pm}0.30$ days and for normal location, $2.80{\pm}0.20$ days. Average runtime was $2.92{\pm}0.31$ days and other forms took $2.88{\pm}0.22$ days. In the future, follow up research would be needed to evaluate the efficiency of the cells collected from the initial passage and the latter passage as stem-cells and taking into consideration the less than 3 days'time for the subculture, it could be concluded that the research efficiency and fast cultivation would be sufficiently effective.

• Journal of Life Science
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• v.26 no.3
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• pp.331-337
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• 2016

Although fibroblast growth factor 23 (FGF23) is exclusively produced in osteoblasts and osteocytes, its main target is the kidney, where it decreases phosphate reabsorption by suppressing Na-phosphate cotransporters. Independently of its action on phosphate homeostasis, FGF23 also inhibits bone formation in vivo. In a calvarial osteoblastic cell model, FGF23 was shown to negatively affect extracellular matrix mineralization. This study investigated whether FGF23 had similar effects on osteoblast maturation, including differentiation and mineralization of bone marrow-derived mesenchymal stem cells (MSCs). D1 MSCs were cultured in an osteogenic medium containing β-glycerophosphate, ascorbic acid, and dexamethazone. Osteoblastic differentiation was evaluated by alkaline phosphatase (Alp) staining, and matrix mineralization was evaluated by alizarin red staining and calcium deposition. The expression of differentiation-stimulating genes Runx2, Alp, and osteocalcin and mineralization-inhibiting genes Enpp1 and Ank was analyzed using semiquantitative RT-PCR. Supraphysiological doses of FGF23 did not stimulate proliferation or osteoblastic differentiation of MSCs. Matrix mineralization 1, 2, and 3 weeks after the FGF23 treatment did not vary between control and FGF23 groups, although time-dependent enhancement of mineralization was obvious. Calcium deposition was also unchanged after the FGF23 treatment. mRNA expression levels of differentiation- and mineralization-related genes were also similar between the groups. Despite these negative findings, FGF23 signaling through FGF receptors seemed to function normally, with phosphorylation of the Erk protein more evident in the FGF23 group than in controls. These findings suggest that unlike calvarial osteoblasts, FGF23 is not likely to affect osteoblastic differentiation and mineralization of MSCs.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.8
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• pp.618-626
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• 2019

Stem cell therapy is not expected to bestow any therapeutic benefit because of the low engraftment rates after transplantation.Various cell-carrying scaffolds have been developed in order to overcome this problem. When the scaffold is formed by 3-dimensional (3D) printing, it is possible to create various shapes of scaffolds for specific regions of injury. At the same time, scaffolds provide stem cells as therapeutic-agents and mechanically support an injured region. PCL is not only cost effective, but it is also a widely used material for 3D printing. Therefore, rapid and economical technology development can be achieved when PCL is printed and used as a cell carrier. Yet PCL materials do not perform well as cell carriers, and only a few cells survive on the PCL surface. In this study, we tried to determine the conditions that maximize the cell-loading capacity on the PCL surface to overcome this issue. By applying a plasma treated condition and then collagen coating known to improve the cell loading capacity, it was confirmed that the 3% collagen coating after plasma treatment showed the best cell engraftment capacity during 72 hours after cell loading. By applying the spheroid cell culture method and scaffold structure change, which can affect the cell loading ability, the spheroid cell culture methods vastly improved cell engraftment, and the scaffold structure did not affect the cell engraftment properties. We will conduct further experiments using PCL material as a cell carrier and as based the excellent results of this study.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.132-137
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• 2003

Antioxidant and anti-inflammatory potentials of various grape extracts were evaluated. Extracts from Kyho seed, Kyho stem, and Campbell seed showed potent 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activities compared to resveratrol $(IC_{50}=16.9,\;21.5,\;21.9,\;34.6\;{\mu}g/mL,\;respectively)$, among which, antioxidant effect of Kyho seed extract were similar to that of vitamin C $(IC_{50}=12.2\;{\mu}g/mL)$. These extracts also exhibited inhibitory activities on lipopolysaccharide (LPS)-induced prostaglandin $E_2$ production and nitrite formation in mouse macrophage RAW 264.7 cells at $50\;{\mu}g/mL$. Kyho stem and seed extracts showed growth inhibitory activities in human lung and colon cancer cells. These results suggest the potential roles of grape extracts as antioxidants and anti-inflammatory agents.

• Health and Mission
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• s.6
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• pp.54-54
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• 2006

• 한국생물공학회:학술대회논문집
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• 2005.10a
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• pp.51-67
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• 2005

• The Science & Technology
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• no.6 s.445
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• pp.66-67
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• 2006

• The Monthly Diabetes
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• s.286
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• pp.30-35
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• 2013