• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.2
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• pp.145-152
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• 2016

Epidermis is continuously regenerated by keratinocyte stem cells (KSCs) residing in basement membrane, which is critical to the survival of an organism. KSCs are believed to persist during the whole lifetime and generate an enormous number of keratinocytes, required for the maintenance of epidermis, through transit amplifying cells dividing definite times until they become differentiated. In this report, we have developed a phenolic compound, paeonol, purified from Moutan Cortex, as a KSC proliferation activator, by screening about 350 herbal compounds. The cell proliferation activation by paeonol is specific for KSC not for keratinocyte, and no significant difference in the expression of p63 protein, a KSC marker, in KSCs treated with paeonol was observed in FACS analysis with anti-p63 antibody. In the colony forming assay, paeonol-treated KSC showed improved colony forming activity more than 1.3 fold. In addition, the result of PCR array shows that the activity of paeonol is through several signal pathways involving stem cell functions. These results suggest that paeonol could enhance KSC proliferation activity without reduction in stemness and could be applied to cosmetics as a KSC activating ingredient.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.511-515
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• 2006

The chemical composition and antioxidative activities of Platycodon grandiflorum leaves and stems was investigated in order to evaluate the potential as functional food material. The moisture contents of leaves and stems were 84.31% and 75.91%, respectively. The Ca content was the highest in leaves (351.49 mg%) and stems (217.56 mg%). The major free sugar of leaves was glucose (1,729.87 mg%) However major free sugar of stems was fructose (734.91 mg%). Glutamic acid (242.91 mg%) and arginine (228.60 mg%) in leaves were major amino acids, lysine (110.08 mg%) and glutamic acid (80.40 mg%) in stems were major amino acids. Oleic acid and linoleic acid were major fatty acids in crude fat of both leaves and stems. DPPH free radical scavenging activities of fractions from leaves and stems were rising with increasing amount of fractions. Like antioxidant activity, the reducing power of fractions from leaves and stems was also dependent on concentration while butanol fraction of stems showed the highest reducing power.

• Development and Reproduction
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• v.14 no.2
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• pp.43-50
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• 2010

Recently induced pluripotent stem (iPS) cells are derived from somatic cells by ectopic expression of several transcription factors (reprogramming factors) using technology of somatic cell reprogramming. iPS cells are able to selfrenew and differentiate into all type of cells in the body similarly to embryonic stem cells. Because iPS cells have advantages that can avoid immune rejection after transplantation and ethical issues unlike embryonic stem cells, research on iPS has made significant progress since the first report by Yamanaka in 2006. Nevertheless of many advantages of iPS, safer methods to introduce reprogramming factors into somatic cells must be developed due to safety concerns regarding viral vectors, and safer reprogramming factors to substitute the oncogenes should be evaluated for clinical application of iPS. Here we discuss the recent progress in reprogramming factors in embryonic stem cells, oocytes, and embryos, and discuss further research for finding new, more reliable and safer reprogramming factors.

• Development and Reproduction
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• v.14 no.4
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• pp.253-259
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• 2010

DNA methylation is one of the major epigenetic regulations of gene expression. The DNA methylation patterns are dramatically changed during gametogenesis and embryogenesis, and especially, it has been known that embryonic stem cells show a distinct methylation pattern. In this study, we examined the methylation patterns of imprinting genes, H19, Igf2r, and Snrpn, in stem cells induced from fertilized embryo (fES) and somatic cell nuclear transferred embryo (ntES). The methylation pattern of H19 gene in both fES and ntES were similar. However, the methylation patterns of Igf2r and Snrpn in ntES (hypermethylated) were slightly different from fES cells.

• Korean Journal of Plant Tissue Culture
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• v.22 no.3
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• pp.131-135
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• 1995

Physiologically modified stem nodes derived from ex vitro and in vivo explants of hybrid aspen (Populus alba L.X P.grandidentata Michx. 'Crandon') were tested for their multiple shoot regeneration capacity using a broad spectrum dosage of cytokinins. Ex vitro derived stem nodes with excised axillary buds at the time of culture produced 11 to 13 multiple shoots on 20 to 30 $\mu$M zeatin containing Woody Plant Medium (WPM) after 6 weeks. Excision of axillary bud sprouts after 2 weeks of culture and culture of the remaining stem nodes on WPM with 1.0 to 2.0 $\mu$M BA or 10 to 30 $\mu$M zeatin produced 13 to 15 and 7 to 8 shoots per explant, respectively, Multiple tiny shoots were produced when in vivo derived stem nodes (on which all leaves were removed) were cultured on WPM with 30 to 50 $\mu$M 2iP or 20 to 50 $\mu$M zeatin. The greatest number of multiple tiny shoot proliferation (32 to 50 shoots per explant) were obtained when the explants were cultured on media containing 20 $\mu$M zeatin. Successful transplanting of these multiple shoots into the greenhouse and/or nursery was achieved.

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.5-12
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• 2008

Objectives : Showing that Bong-Han corpuscles(BHC) are suppliers of the stem cells in adulthood, and the Bong-Han ducts(BHD) are transportation routes of stem cells. Methods : BHC and BHD were obtained from the internal organ-surfaces of rats. The sliced BHC and BHD were immunostained with various stem cell markers. Extracellular matrices were also analyzed by immunohistochemistry. Result : The presence of mesenchymal stem cells was confirmed by the expression of Integrin beta 1, Collagen type 1 and Fibronectin. But CD54 was not expressed. The hematopoietic stem cell marker, Thy 1 was strongly expressed. BHDs showed Collagen type 1, Fibronectin, and vWF expression. Conclusion : Both hematopoietic and mesenchymal stem cell markers were expressed strongly in BHC similarly as in bone marrow. An endothelial cell marker(vWF) demonstrated the possibility of the stem cell transportation routes of BHD.

• Food Science and Preservation
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• v.8 no.4
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• pp.475-480
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• 2001

Yields of bamboo extracts were 1.0∼1.5% in stalks and 3.1∼3.2% (w/w) in leaves. Electron donating ability of extracts from stalks was 62% in Maengjongjuk, 55% in Somdae and 52% in Wangdae, while that of leaf extracts showed very low level. On the contrary, nitrite-scavenging activity was higher in leaf extracts than stalk extracts, and the activity was 63, 57 and 55% in leaf extracts of Maengjongjuk, Wangdae and Somdae, respectively. Antimicrobial activity was examined against 7 major strains which cause food poisoning, and extracts of bamboo stalks showed somewhat activity, while leaf extracts showed merely or no activity according to strains. But all extracts showed relatively strong antimicrobial activity against Staphylococcus aureus and Vibrio parahaemolyticus, and extracts of Somdae stalks and Maengjongjuk leaves showed antimicrobial antimicrobial activity against those strains on 100${\mu}\ell$/disc concentrate.

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.3
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• pp.365-371
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• 2020

In this study, in order to recycle the stems of opuntia cactus discarded after harvesting the fruit, the cactus stems were powdered and applied as a cement-based admixture. The powder of cactus stem was mixed into the mortar, and its effect on the fresh properties and strength of the mortar was studied. The results were compared with the properties of mortars produced by mixing with a retarder sugar and a viscosity agent methyl-cellulose, which are conventional saccharide-based admixtures. Based on the test results, the cactus stem powder did not clearly show the effect as a retarding agent, whereas the flow and the air content were similar to those of the mortar mixed with methyl-cellulose. This indicated that the cactus stem powder can be used as a viscosity agent. It was found that the strength of the mortar tended to increase when the mixing ratio of the cactus stem powder was lower than 0.3%.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.3
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• pp.199-206
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• 2010

Stem-cell therapy has the potential to improve vision in patients with untreatable retinal disease. Various types of cell source including fetal, embryonic and adult stem cells, intrinsic and extrinsic factors for differentiation into retinal progenitors and transplantation mode were discussed in this review. Experimental approaches have successfully induced photoreceptor precursor cells and retinal pigment epithelium. Stem-cell-based therapy is a promising treatment to restore vision in patients with retinal disease, in spite of the challenges.

• 농업기술회보
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• v.50 no.3
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• pp.28-29
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• 2013

국내 토마토 소비가 증가하면서 재배면적과 생산액은 늘어났지만 수량은 계속 정체되어 있다. 이는 국내 토마토 농가의 단위면적 당 생산성이 낮기 때문이다. 이에 따라 국립원예특작과학원에서는 토마토 어린모의 줄기나 가지의 생장점을 두 줄기로 유인해 재배하는 기술을 개발했다. 그 결과 종묘비를 절감하고 생산성도 높일 수 있을 것으로 보인다.