• Journal of Embryo Transfer
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• v.21 no.1
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• pp.35-43
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• 2006

Ions play important roles in various cellular processes including fertilization and differentiation. However, it is little known whether how ions are regulated during early embryonic development in mammalian animals. In this study, we examined changes in $Ca^{2+}\;and\;K^+$ concentrations in embryos and oviduct during mouse early embryonic development using patch clamp technique and confocal laser scanning microscopy. The intracellular calcium concentration in each stage embryos did not markedly change. At 56h afier hCG injection when 8-cell embryos could be Isolated from oviduct, $K^+$ concentration in oviduct increased by 26% compared with that at 14h after injection of hCG During early embryonic development, membrane potential was depolarized (from -38 mV to -16 mV), and $Ca^{2+}$ currents decreased, indicating that some $K^+$ channel might control membrane potential in oocytes. To record the changes in membrane potential induced by influx of $Ca^{2+}$ in mouse oocytes, we applied 5 mM $Ca^{2+}$ to the bath solution. The membrane potential transiently hyperpolarized and then recovered. In order to classify $K^+$ channels that cause hyperpolarization, we first applied TEA and apamin, general $K^+$ channel blockers, to the bath solution. Interestingly, the hyperpolarization of membrane potential still appeared in oocytes pretreated with TEA and apamin. This result suggest that the $K^+$ channel that induces hyperpolarization could belong to another $K^+$ channel such as two-pore domain $K^+(K_{2P})$channel that a.e insensitive to TEA and apamin. From these results, we suggest that the changes in $Ca^{2+}\;and\;K^+$ concentrations play a critical role in cell proliferation, differentiation and reproduction as well as early embryonic development, and $K_{2P}$ channels could be involved in regulation of membrane potential in ovulated oocytes.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.198-204
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• 2014

Ultraviolet B (UV-B) irradiation is a negative factor that induces skin damage, inflammation, and aging. UVB irradiation induces the inflammatory response through interleukin (IL)-6 and IL-8 expression in keratinocytes. In addition, it induces the production of reactive oxygen species (ROS) and the activation of matrix metalloproteinase-1 (MMP-1), which plays an important role in collagen 1 degradation in the extracellular matrix. We investigated the antiaging effects of five kinds of berry in human skin keratinocyte (HaCaT) cells using juice of black raspberry (Rubus occidentalis), blueberry wild (Vacciniun angustifolium) and cultivar (Vacciniun corymbosum), black chokeberry (Aronia melanocarpa (Michx.) Elliott), and mulberry (Morus abla). HaCaT cells irradiated with UV-B exhibited increased ROS generation, as well as IL-6, IL-8, and MMP-1 gene expression, when compared to the control cells that were not irradiated with UV-B. However, pre-treatment of berry juice before UV-B irradiation significantly down-regulated the UV-B-induced ROS generation and inflammatory cytokine and MMP-1 expression. The results suggest that all berries have anti-aging effects including lowering inflammatory cytokine levels, ROS generation, and MMP-1 expression in HaCaT cells during UV-B irradiation.

• Journal of Life Science
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• v.28 no.5
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• pp.615-620
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• 2018

Epigallocatechin-3-gallate (EGCG), one of catechins of green tea, has been known to possess anti-oxidation, anti-inflammation, and anti-cancer effects. The present study analyzed global gene expression changes in EGCG-treated HCT116 cells and p53-null HCT116 cells by oligo DNA microarray analysis. Among the differentially expressed genes in EGCG-treated HCT116 cells, four were selected that are known as tumor suppressor genes (activating transcription factor 3 [ATF3], cyclin dependent kinase inhibitor 1A [CDKN1A], DNA damage-inducible transcript 3 [DDIT3] and non-steroidal anti-inflammatory drug activated gene [NAG-1]) and their expression was compared to the expression of genes in p53-null HCT116 cells. We found that the expression of these genes was not dependent on their p53 status except for NAG-1, which was only up-regulated in HCT116. The results of RT-PCR and Western blot analysis showed that ATF3 up-regulation by EGCG was not affected by the presence of p53, whereas NAG-1 expression was not induced in p53-null HCT116 cells. We also detected ATF3 and NAG-1 expression changes through genistein and resveratrol treatment. Interestingly, genistein could not up-regulate ATF3 regardless of p53 status, but genistein could induce NAG-1 only in HCT116 cells. Resveratrol could significantly induce NAG-1 as well as ATF3 independent of p53 presence. These results indicate that EGCG, genistein and resveratrol may have different anti-cancer effects. Overall, the results of this study may help to increase our understandings of molecular mechanisms on anti-cancer activities mediated by EGCG, genistein and resveratrol in human colorectal cancer cells.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.4-17
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• 2019

Both as a means of improving North-South relations, as well as a necessary component for carrying out research on the past of the Korean peninsula, interest in North Korean cultural resources has been growing in South Korean society. As a result, studies have begun to look beyond North Korean cultural resources themselves and attempt to determine how cultural resources are managed in North Korea. Such studies have tended to investigate laws related to the management of cultural heritage in North Korea, but information gleaned from laws alone is limited. To provide a more complete picture, research must also investigate how cultural resource management laws are applied and enforced and also take into consideration aspects of cultural resource management that are not directed or regulated by law. In this study, we refer to the current National Cultural Resources Protection Laws in order to investigate systems of cultural resource management in North Korea. Furthermore, we conducted interviews with a former North Korean national who had until recently worked as a director of historical sites in North Korea. Through comparisons of information relating to organization, labor power, responsibilities, budget, and other factors of cultural resource management gained through the interviews and the 'National Cultural Resources Protection Laws,' we hoped to gain a fuller understanding of the reality of cultural resource management in North Korea. As a result, we were able to gain a better understanding of the organization and tasks related to cultural resource management and, at the same time, clarify some of the provisions that were unclear in the laws. Throughout the process, we were also able to determine that the management of cultural resources in North Korea is currently inadequate. However, because this study focuses on a specific region and is limited only to historical sites, it is difficult to generalize our findings to the entirety of cultural resource management in North Korea. In order to gain an objective and more accurate understanding of the current state of cultural resource management in North Korea, information must be collected at many levels to be synthesized and compared.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.80-80
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• 2003

${\beta}$-lapachone(${\beta}$-Lap), a natural o-naphthoquinone, presents in the bark of the Lapacho tree. ${\beta}$-Lap is cytotoxic against a variety of human cancer cells and it potentiates the anti-tumor effect of Taxol. In addition, ${\beta}$-Lap has been reported to radiosensitize cancer cells by inhibiting the repair of radiation-induced DNA damage.In the present study, we investigated the cytotoxicity of ${\beta}$-Lap against RKO human colorectal cancer cells as well as the combined effect of ${\beta}$-LaP and ionizing radiation. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h killed almost 90％ of the clonogenic cells. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h or longer also caused massive apoptosis. Unlike other cytotoxic agents, ${\beta}$-Lap did not increase the expression of p53 and p21 and it suppressed the NFkB expression. The expression of Caspase 9 and 3 was minimally altered by ${\beta}$-Lap. Radiation and ${\beta}$-Lap acted synergistically in inducing clonogenic cell death and apoptosis in RKO cells when ${\beta}$-Lap treatment was applied after but not before the radiation exposure of the cells. Interestingly, a 4 h treatment with 5 ${\mu}$M of ${\beta}$-Lap starting 5 h after irradiation was as effective as that starting immediately after irradiation. The mechanisms of ${\beta}$-Lap-induced cell killing is controversial but a recent hypothesis is that ${\beta}$-Lap is activated by NAD(P)H: quinone-onidoreductase (NQO1) in the cells followed by an elevation of cytosolic Ca$\^$2+/ level and activation of proteases leading to apoptosis. It has been reported that NQO1 level in cells is markedly up-regulated for longer than 10 h after irradiation. Indeed, using immunological staining of NQO1, we observed a significant elevation of NQO1 expression in RKO cells 5h after 2-4 Gy irradiation. Such a prolonged elevation of NQO1 level after irradiation may be the reasons why the ${\beta}$-Lap treatment applied S h after irradiation was as effective as that applied immediately after irradiation in killing the cells. In view of the fact that the repair of radiation-induced damage is usually completed within 1-2 h after irradiation, it is highly likely that the ${\beta}$-Lap treahment applied 5 h after irradiation could not inhibit the repair of radiation-induced damage. For in vivo study, RKO cells were injected S.C. into the hind-leg of Nu/Nu mice, and allowed to grow to 130 mm3 tumor. The mice were i.p. injected with ${\beta}$-lapachone or saline 2 h after irradiation of tumors with 10 Gy of X-rays. The radiation induced growth delay was increased by 2.4 $\mu\textrm{g}$/g of ${\beta}$-lapachone. Taken together, we may conclude that the synergistic interaction of radiation and ${\beta}$-Lap in killing cancer cells is not due to radiosensitization by ${\beta}$-Lap but to an enhancement of ${\beta}$-Lap cytotoxicity by radiation through an upregulation of NQO1. The fact that NQO1 is elevated in tumors and that radiation causes prolonged increase of the NQO1 expression may be exploited to preferentially kill tumor cells using ${\beta}$-Lap in combination with radiotherapy.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.573-580
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• 2005

Cholesterol $7\alpha-hydroxylase$ (CYP7A1) is the rate-limiting enzyme in the conversion of cholesterol to bile acids and plays a central role in regulating cholesterol homeostasis. We previously showed that a fermentable $\beta-glucan$ ingestion decreased plasma cholesterol levels due to fecal bile acid excretion elevation involved inincrease of cholesterol $7\alpha-hydroxylase$ mRNA expression and activity. It is proposed that short chain fatty acids (SCFA) produced by cecal and colonic fermentation of soluble fiber are associated with cholesterol-lowering effect of fiber. In the present study, we investigated whether CYP7A1 expression is up-regulated by short chain fatty acids or by hormones in cultured human hepatoma (HepG2) cells. Confluent HepG2 cell were incubated with acetate, propionate, or butyrate at 1 mM concentration for 24 hrs. Acetate as well as propionate increased to 1.8-fold expression of CYP7A1 mRNA than the control. Butyrate also increased 1.5-fold expression of CYP7A1 mRNA. Our data show for the first time that SCFA increase expression of CYP7A1 mRNA. Adding insulin, dexamethasone and triiodothyronine $(1\;{\mu}M)$ to HepG2 cell increased the expression of CYP7A1 mRNA to $150\%,\;173\%,\;141\%$, respectively. These results suggest that SCFA produced by cecal fermentation stimulate enteric nervous system, in which secreted some neuropeptides may be responsible for change in cholesterol and bile acid metabolism. These findings suggest that SCFA are involved in lowering plasma cholesterol levels due to the up-regulation of CYP7A1 and bile acid synthesis.

• Journal of the korean academy of Pediatric Dentistry
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• v.30 no.4
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• pp.643-653
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• 2003

Fibroblast growth factor (FGF) / FGF receptor (FGFR) mediated signaling is required for skeletogenesis in cluding intramembranous and endochondral ossifications Runx2 ($Cbfa1/Pebp2{\alpha}A/AML3$) is an essential transcription factor for osteoblast differentiation and bone formation. Murine calvaria and mandible are concurrently undergoing both intramembranous bone and cartilage formations in the early developmental stage. However the mechanism by which these cartilage formations are regulated remains unclear. To elucidate the effect of FGF signaling on development of cranial sutural cartilage and Meckel's cartilage and to understand the role of Runx2 in these process, we have done both in vivo and in vitro experiments. Alcian blue staining showed that cartilage formation in sagittal suture begins from embryonic stage 16 (E16), Meckel's cartilage formation in mandible from E12. We analyzed by in situ hybridization the characteristics of cartilage cells that type II collagen, not type X collagen, was expressed in sagittal sutural cartilage and Meckel's cartilage. In addition, Runx2 was not expressed in Meckel's cartilage as well as sagittal sutural cartilage, except specific expression pattern only surrounding both cartilages. FGF signaling pathway was further examined in vitro. Beads soaked in FGF2 placed on the sagittal suture and mandible inhibited both sutural and Meckel's cartilage formations. We next examined whether Runx2 gene lies in FGF siganling pathway during regulation of cartilage formation. Beads soaked in FGF2 on sagittal suture induced Runx2 gene expression. These results suggest that FGF signaling inhibits formations of sagittal sutural and Meckel's cartilages, also propose that FGF siganling is involved in the proliferation and differentiation of chondroblasts through regulating the transcription factor Runx2.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.3
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• pp.470-486
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• 1995

Mammary epithelial cells contain a subpopulation of cells with a large proliferativ potential which are responsible for the maintenance of glandular cellularity and are the progenitor cells of mammary cancer. These clonogens give rise to multicellular clonal alveolar or ductal units(AU or DU) on transplantation and hormonal stimulation. To isolate putative mammary clonogens, enzymatically monodispersed rat mammary epithelial cells from organoid cultures and from intact glands are sorted by flow cytometry according to their affinity for FITC labeled peanut lectin(PNA) and PE labeled anti-Thy-1.1 antibody(Thy-1.1) into four subpopulations : cells negative to both PNA and Thy-1.1(B-), PNA+cells, Thy-1.1+cells, and cells positive to both reagents(B+). The in vivo transplantation assays indicate that the clonogenic fractions of PNA+cells from out-growths of organoids in primary cultures for three days in complete hormone medium(CHM) are significantly higher than those of cells from other subpopulations derived from cultrues or from intact glands. Extracellular matrix(ECM) is a complex of several proteins that regulated cell function ; its role in cell growth and differentiation and tissue-specific gene expression. It can act as a positive as well as a negative regulator of cellular differentiation depending on the cell type and the genes studied. Regulation by ECM is closely interrelated with the action of other regulators of cellular function, such as growth factors and hormones. Matrigel supports the growth and development of several different multicellular colonies from mammary organoids and from monodispersed epithelial cells in culture. Several types of colonies are observed including stellate colonies, duct-like structures, two- and three-dimensional web structures, squamous organoids, and lobulo-duct colonies. Organoids have the greatest proliferative potential and formation of multi-cellular structures. Phase contrast micrographs demonstrate extensive intracellular lipid accumulation within the web structures and some of duct-like colonies. At the immunocytochemical and electron micrograph level, casein proteins are predominantly localized near the apical surface of the cells or in the lumen of duct-like or lobulo-duct colonies. Squamous colonies are comprised of several layers of squamous epithelium surrounding keratin pearls as is typical fo squamous metaplasia(SM). All-trans retinoic acid(RA) inhibits the growth of SM. The frequency of lobulo-ductal colony formation increased with the augmentation of RA concentration in these culture conditions. The current study models could provide powerful tools not only for understanding cell growth and differentiation of epithelial cells, but also for the isolation and characterization of mammary clonogenic stem cells.

• Journal of Ginseng Research
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• v.31 no.4
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• pp.181-190
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• 2007

Compound K (CK), a protopanaxadiol ginsenoside metabolite, was previously shown to have immunomodulatory effects. In this study, we isolated the CK rich fractions (CKRF) from Korean Red Ginseng and investigated the regulation of CKRF-mediated inflammatory signaling during Toll-like receptor (TLR)-mediated cellular activation. Among various TLR ligands, CKRF considerably abrogated TLR4- or TLR9-induced inflammatory signaling. Both LPS and CpG-containing oligodeoxynucleotides (CpG-ODN) stimulation rapidly activates mitogen-activated protein kinases [MAPKs; extracellular signal-regulated kinases 1/2 and p38], NF-${\kappa}B$, and expression of pro-inflammatory cytokines tumor necrosis factor-${\alpha}$, and interleukin-6 in murine bone marrow-derived macrophages (BMDMs) in a time- and dose-dependent manner. Of interest, pre-treatment of CKRF in either LPS/TLR4- or CpG-ODN/TLR9-stimulated macrophages substantially attenuated the LPS-induced inflammatory cytokine production and mRNA expressions, as well as MAPK and NF-${\kappa}B$ activation. To our knowledge, this is the first description of the inhibitory roles for CKRF in TLR4- or TLR9-associated signaling in BMDMs. Collectively, these results demonstrate that CKRF specifically modulates distinct TLR4 and TLR9-mediated inflammatory responses, and further studies are urgently needed for their in vivo roles for potential therapeutic uses, such as in systemic inflammatory syndromes.

• Korean Journal of Environment and Ecology
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• v.25 no.5
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• pp.787-798
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• 2011

An arboretum is defined as a collection of facilities that conserve plant species by surveying, collecting, and proliferating and preserving the plants in nature, perform diverse researches on plants and display the plants in exhibition spaces or outdoors as well as provide the public with educational programs and refreshment spaces according to the laws concerned. The public, however, recognizes the exhibition and education functions on plants of arboretum more importantly compared with the roles to survey, collect, and proliferate plants as regulated by the laws. In particular, arboretum plays a role to offer a pivotal educational place in urban area where the public can obtain an hands-on experience and understanding on a wide range of plant species and natural environment. The study aims to estimate the non market environmental values of Daegu Arboretum operated by Daegu Metropolitan City government by using the Contingent Valuation Methods (CVM), which yields the current monetary estimates for the arboretum. The value estimation was undertaken by using the Double-Bound Dichotomous Choice (DBDC) method, and each estimated value was derived from respective functions based on a logit distribution known to include relatively stable estimates according to the shape of the distribution. Considering the statistical fitness test results, the author estimated the amounts of the Willingness To Pay (WTP) such as mean WTP of 12,718 KRW, median WTP of 11,033 KRW, and truncated mean WTP of 11,468 KRW, which represented the annual recreational values per a person visiting Daegu Arboretum respectively. The analysis showed that Daegu Arboretum created the annual environmental values which were estimated to be approximately 16 to 19 billion KRW. The study also has an implication that the valuation method for the environment of Daegu Arboretum may be effectively applied for estimating the values of other types of environmental goods by altering the locations or goods to be analyzed.