• Journal of Plant Biology
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• v.28 no.4
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• pp.285-296
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• 1985

To examine the differentiation and transition of vascular system in Prunus davidiana FR., the mature embyro and developing seedlings were embedded in paraplast and treated by clearing method. In mature embryo, the procambium was connected with the epicotyl-hypocotyl-radicle axis and cotyledons, whereas protophloem and protoxylem were restricted primarily to the mid-vein and two lateral veins of the cotyledonary base. With the onset of germination, protophloem and protoxylem were differentiated both acropetally and basipetally from the cotyledonary base. The first and second leaf traces appeared in the cotyledonary node, and then differentiated bidirectionally toward the epicotyl and the root tip. The 3rd to 6th leaf traces were connected with the cotyledonary traces in hypocotyl. At the part of the root tip, the xylem was a diarch. As the first and second leaf traces were superimposed at the middle part of the root, the diarch xylem was changed to a tetrarch. As the cotyledonary traces were diverged below the root base, the tetrarch xylem was changed to an octarch. It was suggested that the vascular system of the epicotyl might be superimposed on that of the cotyledon-hypocotyl-root during the formation of the primary vascular system of Prunus davidiana.

• The Korean Journal of Ecology
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• v.6 no.4
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• pp.33-59
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• 1983

An investigation has been performed on the flora and life form of the vascular plants at Mt. Sori in Kwangneung from March to November in 1982. In a survey field trip, 539 species, 344 genera, 102 families of plants. are collected. Among them Hylomecon vernale, Aconitum coreanum, A. pseudoproliferum, Adonis amurensis, Anemone raddeana is important plant in this area and they are becoming sparse than past. In the life form spectrum hemiryptophytes is 40.6%.

• Proceedings of the Korean Society of Life Science Conference
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• 2003.10a
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• pp.138-138
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• 2003

• BMB Reports
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• v.45 no.9
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• pp.489-495
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• 2012

Ischemia is a blockage of blood supply due to an embolism or a hemorrhage in a blood vessel. When an organ cannot receive oxygenated blood and can therefore no longer replenish its blood supply due to ischemia, stresses, such as the disruption of blood glucose homeostasis, hypoglycemia and hypoxia, activate the AMPK complex. LKB1 and $CaMKK{\beta}$ are essential activators of the AMPK signaling pathway. AMPK triggers proangiogenic effects through the eNOS protein in tissues with ischemic conditions, where cells are vulnerable to apoptosis, autophagy and necrosis. The AMPK complex acts to restore blood glucose levels and ATP levels back to homeostasis. This review will discuss AMPK, as well as its key activators (LKB1 and $CaMKK{\beta}$), as a central energy regulator and evaluate the upstream and downstream regulating pathways of AMPK. We will also discuss how we can control this important enzyme in ischemic conditions to prevent harmful effects in patients with vascular damage.

• Molecules and Cells
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• v.27 no.3
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• pp.337-343
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• 2009

We developed a novel on-chip activity assay using protein arrays for quantitative and rapid analysis of transglutaminase activity in mammalian cells. Transglutaminases are a family of $Ca^{2+}$-dependent enzymes involved in cell regulation as well as human diseases such as neurodegenerative disorders, inflammatory diseases and tumor progression. We fabricated the protein arrays by immobilizing N,N'-dimethylcasein (a substrate) on the amine surface of the arrays. We initiated transamidating reaction on the protein arrays and determined the transglutaminase activity by analyzing the fluorescence intensity of biotinylated casein. The on-chip transglutaminase activity assay was proved to be much more sensitive than the $[^3H]putrescine$-incorporation assay. We successfully applied the on-chip assay to a rapid and quantitative analysis of the transglutaminase activity in all-trans retinoic acid-treated NIH 3T3 and SH-SY5Y cells. In addition, the on-chip transglutaminase activity assay was sufficiently sensitive to determine the transglutaminase activity in eleven mammalian cell lines. Thus, this novel on-chip transglutaminase activity assay was confirmed to be a sensitive and high-throughput approach to investigating the roles of transglutaminase in cellular signaling, and, moreover, it is likely to have a strong potential for monitoring human diseases.

• Molecules and Cells
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• v.44 no.11
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• pp.830-842
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• 2021

When perceiving microbe-associated molecular patterns (MAMPs) or plant-derived damage-associated molecular patterns (DAMPs), plants alter their root growth and development by displaying a reduction in the root length and the formation of root hairs and lateral roots. The exogenous application of a MAMP peptide, flg22, was shown to affect root growth by suppressing meristem activity. In addition to MAMPs, the DAMP peptide PEP1 suppresses root growth while also promoting root hair formation. However, the question of whether and how these elicitor peptides affect the development of the vascular system in the root has not been explored. The cellular receptors of PEP1, PEPR1 and PEPR2 are highly expressed in the root vascular system, while the receptors of flg22 (FLS2) and elf18 (EFR) are not. Consistent with the expression patterns of PEP1 receptors, we found that exogenously applied PEP1 has a strong impact on the division of stele cells, leading to a reduction of these cells. We also observed the alteration in the number and organization of cells that differentiate into xylem vessels. These PEP1-mediated developmental changes appear to be linked to the blockage of symplastic connections triggered by PEP1. PEP1 dramatically disrupts the symplastic movement of free green fluorescence protein (GFP) from phloem sieve elements to neighboring cells in the root meristem, leading to the deposition of a high level of callose between cells. Taken together, our first survey of PEP1-mediated vascular tissue development provides new insights into the PEP1 function as a regulator of cellular reprogramming in the Arabidopsis root vascular system.

• Korean Journal of Environment and Ecology
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• v.24 no.3
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• pp.264-278
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• 2010

This study was carried out to describe the basic materials of the flora and vegetation for the conservation and management of the Dokdo ecosystem. The vegetation types were investigated by physionomy. 53 taxa of vascular plants were found, including 29 families, 48 genera, 49 species, 1subspecies, and 3 varieties. Among the investigated 53 taxa, it was recorded as follows: 2 Korean endemic plants included Sedum kamtschaticum var. takesimense M.Park and Campanula takesimana Nakai and 6 naturalized plants included Brassica juncea (L.) Czern., Sonchus oleraceus L., Bromus catharticus Vahl, Lepidium virginicumL., Chenopodium album L., and Ipomoea purpurea Roth. In particular, common morning glory (Ipomoea purpurea Roth) was reported for the first time in this survey of Dokdo. Based on physionomy, the main plant communities of Dokdo Island were Aster spathulifolius-Sedum oryzifolium community, Aster spathulifolius-Artemisia Japonica subsp. littoricola community, Fallopia sachalinensis-Cyrtomium falcatum community, Echinochloa crusgalli community, Echinochloa crusgalli var. oryzicola community. The debates have been continuing about a mis-identification of plants. To avoid this debate and manage naturalized and cultivated plants, taxonomist surveys and continual monitoring for the Island are required.

• Journal of Ginseng Research
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• v.41 no.4
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• pp.477-486
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• 2017

Background: Our previous studies have demonstrated that ginsenoside-Rg1 can promote angiogenesis in vitro and in vivo through activation of the glucocorticoid receptor (GR). Furthermore, microRNA (miRNA) expression profiling has shown that Rg1 can modulate the expression of a subset of miRNAs to induce angiogenesis. Moreover, Rb1 was shown to be antiangiogenic through activation of a different pathway. These studies highlight the important functions of miRNAs on ginseng-regulated physiological processes. The aim of this study was to determine the angiogenic properties of Korean Red Ginseng extract (KGE). Methods and Results: Combining in vitro and in vivo data, KGE at $500{\mu}g/mL$ was found to induce angiogenesis. According to the miRNA sequencing, 484 differentially expressed miRNAs were found to be affected by KGE. Among them, angiogenic-related miRNAs; miR-15b, -23a, -214, and -377 were suppressed by KGE. Meanwhile, their corresponding angiogenic proteins were stimulated, including vascular endothelial growth factor, vascular endothelial growth factor receptor-2, endothelial nitric oxide synthase, and MET transmembrane tyrosine kinase. The miRNAs-regulated signaling pathways of KGE were then found by Cignal 45-Pathway Reporter Array, proving that KGE could activate GR. Conclusion: KGE was found capable of inducing angiogenesis both in vivo and in vitro models through activating GR. This study provides a valuable insight into the angiogenic mechanisms depicted by KGE in relation to specific miRNAs.

• Experimental and Molecular Medicine
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• v.50 no.12
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• pp.11.1-11.9
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• 2018

Estrogen has diverse effects on cardiovascular function, including regulation of the contractile response to vasoactive substances such as serotonin. The serotonin system recently emerged as an important player in the regulation of vascular tone in humans. However, hyperreactivity to serotonin appears to be a critical factor for the pathophysiology of hypertension. In this study, we examined the modulatory mechanisms of estrogen in serotonin-induced vasoconstriction by using a combinatory approach of isometric tension measurements, molecular biology, and patch-clamp techniques. $17{\beta}$-Estradiol (E2) elicited a significant and concentration-dependent relaxation of serotonin-induced contraction in deendothelialized aortic strips isolated from male rats. E2 triggered a relaxation of serotonin-induced contraction even in the presence of tamoxifen, an estrogen receptor antagonist, suggesting that E2-induced changes are not mediated by estrogen receptor. Patch-clamp studies in rat arterial myocytes showed that E2 prevented Kv channel inhibition induced by serotonin. Serotonin increased Src activation in arterial smooth muscle required for contraction, which was significantly inhibited by E2. The estrogen receptor-independent inhibition of Src by E2 was confirmed in HEK293T cells that do not express estrogen receptor. Taken together, these results suggest that estrogen exerts vasodilatory effects on serotonin-precontracted arteries via Src, implying a critical role for estrogen in the prevention of vascular hyperreactivity to serotonin.

• Anatomy and Cell Biology
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• v.56 no.3
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• pp.374-381
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• 2023

Although the epiglottis plays a vital role in deglutition, histological studies of the epiglottis and surrounding ligaments associated with swallowing dysfunction are limited. Therefore, we performed histological observations to clarify age-related changes in the morphological characteristics of the epiglottis and surrounding structures. Tissue samples comprising the epiglottis and surrounding structures were collected from corpses that were both orally fed and tubefed during their lifetimes. Following hematoxylin and eosin, Elastica Van Gieson, and immunohistochemical staining procedures, the chondrocytes, connective tissue, and glandular tissue were observed under the epiglottis epithelium, and intervening adipose tissue was observed in the surrounding area. Fatty degeneration of acinar cells was also observed in the glandular tissue, possibly because of aging. Bundles of elastic fibers were present around the vascular wall in the peri-epiglottic ligament, but some were reduced. Furthermore, large amounts of collagen fibers ran toward and through the cartilage, whereas the mesh-like elastic fibers stopped in front of the cartilage. Microfibrils considered to be oxytalan fibers, which are thinner and shorter than elastic fibers, were observed around the vascular wall and in the fiber bundles. Age-related changes included connective tissue fibrosis shown by the large amount of collagen fibers, atrophy of salivary glands, and an accompanying increase in adipose tissue. Regarding stretchability and elasticity, the elastic fibers may have an auxiliary function for laryngeal elevation during deglutition. This suggests that disuse atrophy of the laryngeal organs with or without oral intake might reduce the amount of elastic fiber in older adults.