• Journal of agriculture & life science
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• v.45 no.1
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• pp.15-20
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• 2011

The objective of this study was to develop allometric equations and stem density and biomass expansion factor for Pinus rigida stands in Muju region. The coefficient of determination of the allometric equations in independent variable (dbh) and dependent variable (biomass) was more than 95% with the exception of leaf (78%) and branch(83%). The total biomass was $102Mg\;ha^{-1}$ ($65.9 Mg\;ha^{-1}$ from stem wood, $9.5Mg\;ha^{-1}$ from stem bark, $19.6Mg\;ha^{-1}$ from branch and $7.0Mg\;ha^{-1}$ from leaf). Biomass distribution ratio of Pinus rigida stands showed the highest in stem wood with 64.6%, followed by the branch with 19.2%, stem bark with 9.3% and the leaf with 6.9%. The results indicated that the stem density $(g/cm^{3})$ and the biomass expansion factor were 0.453 and 1.344, respectively.

• Biomedical Science Letters
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• v.22 no.1
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• pp.1-8
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• 2016

Several studies have investigated the various effects of dexamethasone (Dex) on the proliferation and differentiation of mesenchymal stem cells (MSCs). Previously, we reported that co-treatment with L-ascorbic acid 2-phosphate and fibroblast growth factor (FGF)-2 maintained differentiation potential in MSCs through expression of hepatocyte growth factor (HGF). In this study, we investigated the effects of co-treatment with FGF-2 and Dex on the proliferation and differentiation potential of MSCs during a 2-month culture period. Co-treatment with FGF-2 and Dex increased approximately a 4.7-fold higher accumulation rate of MSC numbers than that by FGF-2 single treatment during a 2-month culture period. Interestingly, co-treatment with FGF-2 and Dex increased expression of HGF and maintained adipogenic differentiation potential during this culture period. These results suggest that co-treatment with FGF-2 and Dex preserves the proliferation and differentiation potential during long-term culture.

• Journal of Digital Convergence
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• v.15 no.7
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• pp.415-424
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• 2017

The purpose of this study was to examine the relationship among public's risk characteristics, risk severity, risk perception and risk acceptability of human stem cell technology. The subjects were 300 Koreans selected. The data were analyzed by the exploratory factor analysis, confirmatory factor analysis, correlation analysis and structural equation modeing analysis. The results were as followed. First, public's risk characteristics on human stem cell technology influenced positively on risk severity. Second, public's risk characteristics on human stem cell technology influenced positively on risk perception. Third, public's risk severity on human stem cell technology influenced positively on risk perception. Fourth, public's risk characteristics on human stem cell technology influenced negatively on risk acceptability. Fifth, public's risk severity on human stem cell technology influenced not significantly on risk acceptability. Sixth, public's risk perception on human stem cell technology influenced not significantly on risk acceptability. These results will contribute to develop the risk communication strategy on the acceptability of human stem cell technology.

• BMB Reports
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• v.50 no.2
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• pp.79-84
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• 2017

Emphysema, a pathologic component of the chronic obstructive pulmonary disease, causes irreversible destruction of lung. Many researchers have reported that mesenchymal stem cells can regenerate lung tissue after emphysema. We evaluated if spheroid human adipose-derived mesenchymal stem cells (ASCs) showed greater regenerative effects than dissociated ASCs in mice with elastase-induced emphysema. ASCs were administered via an intrapleural route. Mice injected with spheroid ASCs showed improved regeneration of lung tissues, increased expression of growth factors such as fibroblast growth factor-2 (FGF2) and hepatocyte growth factor (HGF), and a reduction in proteases with an induction of protease inhibitors when compared with mice injected with dissociated ASCs. Our findings indicate that spheroid ASCs show better regeneration of lung tissues than dissociated ACSs in mice with elastase-induced emphysema.

• Development and Reproduction
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• v.21 no.4
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• pp.449-456
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• 2017

The germline stem cells of the Drosophila ovary continuously produce eggs throughout the life-span. Intricate regulation of stemness and differentiation is critical to this continuous production. The translational regulator Nos is an intrinsic factor that is required for maintenance of stemness in germline stem cells. Nos expression is reduced in differentiating cells at the post-transcriptional level by diverse translational regulators. However, molecular mechanisms underlying Nos repression are not completely understood. Through three distinct protein-protein interaction experiments, we identified specific molecular interactions between translational regulators involved in Nos repression. Our findings suggest a model in which protein complexes assemble on the 3' untranslated region of Nos mRNA in order to regulate Nos expression at the post-transcriptional level.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.613-618
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• 2001

For the evaluation of operability of MOV(Motor Operated Valve), the precision prediction of thrust/torque acting on the valve is important. In this paper, the analytical prediction method of thrust/torque was proposed. The design basis stem thrust calculation typically considers the followings: Packing thrust, Stem rejection load, design basis differential pressure load. In general, test results show that temperature, pressure, fluid type, and differential pressure, independently and combination, all have an effect on the friction factor. The prediction results of thrust/torque are well agrement with dynamic test results.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.51-56
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• 2002

A recombinant transfer vector pBacSCF was constructed by inserting huamn stem cell factor (hSCF) cDNA into plasmid pBacPAK8. BmN cells were co-transfected with modified Bombyx mori, nuclear polyhedrosis virus (BmBacPAK) DNA and the recmbinant transfer vector to construct a recombinant baculovirus containing hSCE gene. DNA dot blotting and RNA dot blotting demonstrated that the hSCE gene was contained in the recombinant virus and transcribed. The recombinant baculovirus was infectious to BmN cells and to silkworm. SDS-PAGE analysis showed a specific band of expressed product in the extract of infected cells and in the heamolymph of infected larvae. Bioactivity of the recombinant hSCE was determined with W-1 cell line and MTT colorimetric method in synergy with interlukin-3 (IL-3). These results revealed that the hSCF gene was over-expressed in cultured cells and lavae of silkworm.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.18-18
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• 2002

This study was to investigate the effect of neurotrophic factors on neural cell differentiation in vitro derived from human embryonic stem (hES, MB03) cells. For neural progenitor cell formation derived from hES cells, we produced embryoid bodies (EB: for 5 days, without mitogen) from hES cells and then neurospheres (for 7 - 10 days, 20 ng/㎖ of bFGF added N2 medium) from EB. And then finally for the differentiation into mature neuron cells, neural progenitor cells were cultured in ⅰ) N2 medium (without bFGF), ⅱ) N2 supplemented with brain derived neurotrophic factor (BDNF, 5ng/㎖) or ⅲ) N2 supplemented with platelet derived growth factor-bb (PDGF-bb, 20ng/㎖) for 2 weeks. (omitted)

• The Korean Journal of Pain
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• v.36 no.1
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• pp.72-83
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• 2023

Background: Globally, spinal cord injury (SCI) results in a big burden, including 90% suffering permanent disability, and 60%-69% experiencing neuropathic pain. The main causes are oxidative stress, inflammation, and degeneration. The efficacy of the stem cell secretome is promising, but the role of human neural stem cell (HNSC)-secretome in neuropathic pain is unclear. This study evaluated how the mechanism of HNSC-secretome improves neuropathic pain and locomotor function in SCI rat models through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities. Methods: A proper experimental study investigated 15 Rattus norvegicus divided into normal, control, and treatment groups (30 µL HNSC-secretome, intrathecal in the level of T10, three days post-traumatic SCI). Twenty-eight days post-injury, specimens were collected, and matrix metalloproteinase (MMP)-9, F2-Isoprostanes, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β, and brain derived neurotrophic factor (BDNF) were analyzed. Locomotor recovery was evaluated via Basso, Beattie, and Bresnahan scores. Neuropathic pain was evaluated using the Rat Grimace Scale. Results: The HNSC-secretome could improve locomotor recovery and neuropathic pain, decrease F2-Isoprostane (antioxidant), decrease MMP-9 and TNF-α (anti-inflammatory), as well as modulate TGF-β and BDNF (neurotrophic factor). Moreover, HNSC-secretomes maintain the extracellular matrix of SCI by reducing the matrix degradation effect of MMP-9 and increasing the collagen formation effect of TGF-β as a resistor of glial scar formation. Conclusions: The present study demonstrated the mechanism of HNSC-secretome in improving neuropathic pain and locomotor function in SCI through antioxidant, anti-inflammatory, anti-matrix degradation, and neurotrophic activities.

• Journal of Korean Neurosurgical Society
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• v.60 no.4
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• pp.404-416
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• 2017

Objective : Functional and neural tissue recovery has been reported in many animal studies conducted with stem cells. However, the combined effect of cytokines and stem cells has not yet been adequately researched. Here, we analyzed the additive effects of granulocyte colony-stimulating factor (GCSF) on adipose-derived stem cells (ADSCs) infusion in the treatment of acute spinal cord injury (SCI) in rats. Methods : Four days after intrathecal infusion tubes implantation in Sprague-Dawley rats, SCI was induced with an infinite horizon impactor. In the Sham group (n=5), phosphate-buffered saline was injected 3, 7, and 14 days after SCI. GCSF, ADSCs, and ADSCs with GCSF were injected at the same time in the GCSF (n=8), ADSC (n=8), and ADSC+GCSF groups (n=7), respectively. Results : The ADSC and ADSC+GCSF groups, but not the GCSF group, showed significantly higher Basso-Beattie-Bresnahan scores than the Sham group during 8 weeks (p<0.01), but no significant difference between the ADSC and ADSC+GCSF groups. In the ladder rung test, all four groups were significantly different from each other, with the ADSC+GCSF group showing the best improvement (p<0.01). On immunofluorescent staining (GAP43, MAP2), western blotting (GAP43), and reverse transcription polymerase chain reaction (GAP43, nerve growth factor), the ADSC and ADSC+GCSF groups showed higher levels than the Sham and GCSF groups. Conclusion : Our analyses suggest that the combination of GCSF and ADSCs infusions in acute SCI in the rat does not have a significant additive effect. Hence, when combination agents for SCI stem cell therapy are considered, molecules other than GCSF, or modifications to the methodology, should be investigated.