• International Journal of Advanced Culture Technology
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• v.11 no.4
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• pp.263-272
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• 2023

We investigated and analyzed students' perceptions of their choice of science subjects in the high school credit system and the reasons for their choice. To achieve this, the selection of science subjects was investigated for the second year of S high school over the past three years. Students selected an average of 1.54 science subjects, and it was found that the rate of selection of science subjects was gradually increasing by year. Students chose high in the order of life science I, earth science I, chemistry I, physics I, etc. in the science subject group. Students who wish to enter the natural and engineering fields chose life science I, chemistry I, physics I, etc., while, students who wish to enter the humanities society chose society and culture, life science I, ethics and thought, etc. On the other hand, the reason for choosing science subjects was 'related to college admission', followed by 'aptitude and interest', 'career and real life help', etc. physics I, chemistry I, etc., were high in the subjects selected according to the 'related to college admission'. The subjects selected according to 'aptitude and interest' were high in life science I, earth science I, etc. Physics I, chemistry I, etc. are recognized as subjects necessary for college entrance, and life science I, earth science I, etc., are found to be related to their interests and aptitudes.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.270-276
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• 2006

We evaluated the effects of extracts of Tsunokaori tangor peel on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin $E_2\;(PGE_2)$ in RAW 264.7 cells. The ethyl acetate fraction of Tsunokaori tangor peel (EA-TTP) markedly inhibited the production of NO and $PGE_2$ in LPS-stimulated RAW 264.7 cells. Consistent with these findings, the expression levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins were down-regulated in a dose-dependent manner. Additionally, EA-TTP decreased the expression iNOS mRNA but not COX-2 mRNA. To determine the upstream signaling mechanism for the down-regulation of LPS-induced iNOS expression, we investigated the effect of EA-TTP on the degradation and re-synthesis of $I{\kappa}B{\alpha}$. EA-TTP dose-dependently delayed $I{\kappa}B{\alpha}$ degradation and increased $I{\kappa}B{\alpha}$ re-appearance following degradation, suggesting this as the mechanism by which EA-TTP suppressed iNOS gene expression. The EA-TTP also dose-dependently reduced the expression of the cellular stress-response protein heme oxygenase-1, and inhibited the LPS-induced sustained activation of extracellar signal-regulated kinase (ERK).

• BMB Reports
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• v.56 no.8
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• pp.463-468
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• 2023

Screening for genetic defects in the cells should be examined for clinical application. The Pearson syndrome (PS) patient harbored nuclear mutations in the POLG and SSBP1 genes, which could induce systemic large-scale mitochondrial genome (mtDNA) deletion. We investigated iPSCs with mtDNA deletions in PS patient and whether deletion levels could be maintained during differentiation. The iPSC clones derived from skin fibroblasts (9% deletion) and blood mononuclear cells (24% deletion) were measured for mtDNA deletion levels. Of the 13 skin-derived iPSC clones, only 3 were found to be free of mtDNA deletions, whereas all blood-derived iPSC clones were found to be free of deletions. The iPSC clones with (27%) and without mtDNA deletion (0%) were selected and performed in vitro and in vivo differentiation, such as embryonic body (EB) and teratoma formation. After differentiation, the level of deletion was retained or increased in EBs (24%) or teratoma (45%) from deletion iPSC clone, while, the absence of deletions showed in all EBs and teratomas from deletion-free iPSC clones. These results demonstrated that non-deletion in iPSCs was maintained during in vitro and in vivo differentiation, even in the presence of nuclear mutations, suggesting that deletion-free iPSC clones could be candidates for autologous cell therapy in patients.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2003.10a
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• pp.109-109
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• 2003

• Journal of Science Education
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• v.36 no.1
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• pp.1-13
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• 2012

What is the life of an assistant professor working at a college of education look like? The purpose of this paper is to describe and understand the life of an assistant professor as a science education researcher and as a teacher educator from exploring his life in a local national university. The researcher (I) conducted an autobiographic research in which I reconstructed and reflected my life by myself. I collected data/records on the life of myself, and developed a framework to classify them. The life of an assistant professor was categorized into the official life at the university and the personal life, and the former was sorted into education, research, and service and the latter was divided into personal and family. From the various profiles of my life, I found the main theme of 'change' and 'learning,' from which I reconstructed my life in narratives. I can express myself as an assistant professor with 'from myself to others,' 'balancing society and isolation,' and 'increasing room to maneuver through continuous learning.' I reflected my life and the role of a professor at a college of education, and discussed the educational implication of the result.

• Journal of Ginseng Research
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• v.44 no.2
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• pp.332-340
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• 2020

Background: The valuable medicinal plant Panax ginseng has high pharmaceutical efficacy because it produces ginsenosides. However, its yields decline because of a root-rot disease caused by Ilyonectria mors-panacis. Because species within Ilyonectria showed variable aggressiveness by altering ginsenoside concentrations in inoculated plants, we investigated how such infections might regulate the biosynthesis of ginsenosides and their related signaling molecules. Methods: Two-year-old ginseng seedlings were treated with I. mors-panacis and I. robusta. Roots from infected and pathogen-free plants were harvested at 4 and 16 days after inoculation. We then examined levels or/and expression of genes of ginsenosides, salicylic acid (SA), jasmonic acid (JA), and reactive oxygen species (ROS). We also checked the susceptibility of those pathogens to ROS. Results: Ginsenoside biosynthesis was significantly suppressed and increased in response to infection by I. mors-panacis and I. robusta, respectively. Regulation of JA was significantly higher in I. robusta-infected roots, while levels of SA and ROS were significantly higher in I. mors-panacis-infected roots. Catalase activity was significantly higher in I. robusta-infected roots followed in order by mock roots and those infected by I. mors-panacis. Moreover, I. mors-panacis was resistant to ROS compared with I. robusta. Conclusion: Infection by the weakly aggressive I. robusta led to the upregulation of ginsenoside production and biosynthesis, probably because only a low level of ROS was induced. In contrast, the more aggressive I. mors-panacis suppressed ginsenoside biosynthesis, probably because of higher ROS levels and subsequent induction of programmed cell death pathways. Furthermore, I. mors-panacis may have increased its virulence by resisting the cytotoxicity of ROS.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.105-105
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• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2005.10a
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• pp.105-105
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• 2005

• Journal of Life Science
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• v.17 no.4 s.84
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• pp.568-574
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• 2007

Lignin degrading bacterium Pseudomonas sp. LG2 was able to degrade lignin substrate to a lot of APPL compound. APPL compound was detected in culture supernatants from Pseudomonas sp. LG2 grown with BSC(brewer's spent grain). FAE(ferulic acid esterase) and xylanase are induced from Pseudomonas sp. LG2 in the presence of carbon sources such as oat spelt xylan, HBSG I, II(hydrolyzed brewer's spent grain I, II) and AFBSG(autoclaved fraction from brewer's spent grain). However, xylanase and FAE are not induced by growth of Pseudomonas sp. LG2 on xylose and arabinose. Pseudomonas sp. LG2 is grown on medium containing oat spelt xylan, HBSG I, II and AFBSG and the induction of FAE and xylanase activities of extracellular proteins determined during 14 days. Maximum level of xylanase activity(5.3 U/mg) found at 6 days in culture contained oat spelt xylan as carbon source, whereas maximum level of FAE activity(15.4 mU/mg) was found at 8 days in culture contained AFBSG as carbon source. Most ferulic acid was released in culture supernatants when Pseudomonas sp. LG2 grown on oat spelt xylan, HBSG I, II and AFBSG. FAE of extracellular enzymes was also specific activity on methyl ferulic acid, methyl caffeic acid and methyl p-coumaric acid respectively, but not methyl sinapinic acid, methyl vanillic acid and methyl gallic acid.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2005.10a
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• pp.129-129
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• 2005