• Korean Journal of Plant Resources
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• v.21 no.5
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• pp.362-367
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• 2008

In order to investigate the effect of plant growth regulators on effective in vitro micropropagation, apical meristems of Pulsatilla cernua var. koreana were cultured on Murashige and Skoog's (MS) medium with 2,4-D, NAA, TDZ and BA. Media containing 2,4-D and kinetin, 2,4-D and TDZ, NAA and TDZ were not effective on callus induction. However, embryogenic or organogenic callus was obtained on media containing NAA and BA. Especially, on MS medium with 0.5mg/L NAA and 1.0mg/L BA was optimal for a high frequency (62%) of shoot or shoot bud obtained from callus. Callus proliferation, shoot multiplication and elongation were significantly increased by adding 10% coconut water on MS media with 0.5mg/L NAA and 1.0mg/L BA. Repeated subculturing of in vitro grown shoots resulted in propagation rate of 12.9 shoots per explant every 30 days. Root formation from the adventitious shoots was not easily achieved. However, roots were only produced through callus on MS medium with 2.0mg/L NAA alone or 0.5mg/L NAA and 1.0mg/L BA. These roots were used materials for callus and shoot production repetitively.

• Korean Journal of Plant Resources
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• v.27 no.1
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• pp.51-59
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• 2014

In this study, we developed a high frequency watermelon regeneration system using three breeding lines ('B02', 'B05' and 'D04') of watermelon (Citrullus lanatus (thunb.) Matsum. & Nakai) which are differed in their fruits in shape, color of pericarp and flesh. The highest frequency of explants with callus was observed by using explants that consist of cotyledon proximal part end in all breeding lines, and the highest rate of callus induction was obtained on MS medium containing 1.0 mg/L BAP + 0.5 mg/L IAA for 'B02' (94%), 3.0 mg/L BAP for 'B05' (95%), 3.0 mg/L BAP + 0.1 mg/L IAA for 'D04' (90%). The highest shoot regeneration rates from derived callus were obtained on MS medium containing 1.0 mg/L BAP + 0.5 mg/L IAA for 'B05' (94%), and then a 'B02' (81%) with a same culture conditions, and the lowest regeneration was obtained on MS medium containing 1.0 mg/L BAP for 'D04' (56%). Regenerated plants showed the best rates of root formation on MS containing 0.1 mg/L IBA for 'B02' (67%), 0.1 mg/L NAA for 'B05' (87%), 0.5 mg/L IAA for 'D04' (88%). The regenerated plants showed a 100% survival rate in soil condition. The tissue culture and regeneration conditions obtained from this study will be useful for regenerating plants in breeding applications, and will be a useful tool for further genetic transformation studies on watermelons.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.221-227
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• 2005

Apoptosis of Prunus salicina Lindl. cv. Soldam, which possesses hematopoiesis, osteoporosis prevention, and antimutagenic effects, at different growth stages was evaluated. Cytotoxic effect of acetone extracts of immature fruits against various tumor cell lines was higher than that of mature fruits, particularly in hormone-independent human breast cancer, MDA-MB-231 cell line. Immature fruit extract increased expression level of pro-apoptotic protein Bax and reduced that of anti-apoptotic protein Bcl-2, and stimulated caspase-3 activity in MDA-MB-231 cells. Results suggest immature fruit of P. salicina Lindl. cv. soldam to be natural source for development of functional food and medical agents to prevent human breast cancer.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.149-153
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• 1992

Antioxidative effects of crude ethanol extract of the Rhus javanica L. and its fractionates with various synergists on the oxidation of palm oil, lard and soybean oil were compared with induction period(IP) using a Rancimat test. Addition of 200 ppm of the crude extract with phosphoric acid to palm oil extended IP 2.89 times as much as that of control and ethyl acetate fractionate extended IP 4.18 times at the same condition. To lard, 600 ppm of chloroform fraction with 200 ppm of ${\delta}-Tocopherol$ extended IP 13.42 times as much as that of control. 200 ppm of each fraction with various synergists were added to palm oil and lard, and oxidative stability of the oils were monitored by measuring POV, AV, and TBA value. The POV of palm oil containing 200 ppm of ethyl acetate and chloroform fraction with 200 ppm of phosphoric acid after 27 days storage at $60^{\circ}C$ were 8.9 meq/kg and 9.4 meq/kg respectively while the POV of control was 98.3 meq/kg at the same condition. AV and TBA value were also lower than that of control. The POV value of lard containing same amount of ethyl acetate and chloroform fraction with ${\delta}-Tocopherol$ after 12 day storage at $60^{\circ}C$ were 20.0meq/kg and 10.7 meq/kg respectively while the POV of control was 161.1 meq/kg at the same condition. AV and TBA value were also lower than that of control.

• Korean Journal of Food Science and Technology
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• v.47 no.2
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• pp.246-253
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• 2015

In this study, we evaluated the lipoprotein lipase (LPL) inhibitory activity of 11 water extracts derived from Cinnamomum cassia Blume, Sarcodon aspratus, Cordyceps militaris, Crataegus pinnatifida Bunge, Corni fructus, Allium cepa, Coix lacryma-jobi, Plantago asiatica L., Lentinus edodes, Rosa rugosa, and Foeniculum fructus. The results of the LPL secretion and activity assay showed Sarcodon aspratus (NE) extract have an LPL secretion inhibitory acitivity. The cause of reduction in LPL secretion after NE treatment was investigated using molecular biology methods. NE treatment affected the LPL content in cells, but did not affect LPL mRNA expression. It also increased the mRNA expression level of sortilin-related receptor LDLR class A (SorLA), a receptor that induces endocytosis and intracellular trafficking of LPL. Finally, cell fractionation revealed that NE treatment induced the expression of CCAAT-enhancer-binding protein beta ($C/EBP{\beta}$), a SorLA transcription factor, in the nuclei of 3T3-L1 adipocytes. These results show that NE's anti-obesity effect involves inhibition of LPL secretion through $C/EBP{\beta}$-mediated induction of SorLA expression.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1199-1206
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• 2006

Plasminogen kringle 5 is a potent inhibitor of endothelial tell proliferation like an endogenous angiogenesis inhibitor, angiostatin consisting of plasminogen kringles 1-4. In this study, we produced the recombinant protein of plasminogen kringle 5 (PK5) employing an Pichia expression system and examined its. effect on~endothelial cell migration and its possible inhibitory mechanism. PK5 was expressed in Pichia pastoris GS115 by fusion of the cDNA spanning from Thr456 to Phe546 to the secretion signal sequence of a-factor prepro-peptide. After methanol induction, the secreted PK5 was purified by using S-spin column. SDS-PACE analysis of the purified protein showed one major band of approximately 10kDa. In in vitro migration assays, the purified protein inhibited dose-dependently the migration of human umbilical endothelial cells (HUVECs) induced by basic fibroblast growth factor (bFGF) or vascular endothelial growth factor (VEGF) with an $IC_{50}$ of approximately 500nM. Accordingly, it inhibited bfGF-stimulated extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation in HUVECs at 500nM. In addition, it also potently inhibited bFGF-induced cytoskeletal rearrangement of HUVECs. Thus, these results suggest that Pichia-produced PK5 effectively inhibits endothelial cell migration, in part by suppression of ERK1/2 activation and blocking cytoskeleton rearrangement.

• Journal of Life Science
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• v.24 no.9
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• pp.1012-1018
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• 2014

Sasa quelpaertensis Nakai (Korean name, Jeju-Joritdae) is one of the most abundant plants on Mt. Halla, Jeju Island, and it has long been used in traditional medicines. Recent studies have reported it as possessing various beneficial functions, including anti-inflammatory, anti-diabetic, anti-hypertension, anti-gastritis, anti-oxidant, and anti-cancer effects. However, the molecular mechanisms of its anti-cancer activity have not been clearly elucidated. In this study, we investigated the anti-cancer effects and mechanism of S. quelpaertensis on human colon cancer HT-29 cells. Cell growth inhibition by S. quelpaertensis was determined by MTT assay. Apoptosis was performed by DNA fragmentation, flow cytometry with propidium iodide staining (PI), and reverse transcription-polymerase chain reaction (RT-PCR) to confirm the anti-apoptotic factors, such as inhibitor of apoptosis (IAP) family members. $NO^{\bullet}$ production was determined by Griess assay. S. quelpaertensis treatment resulted in the time- and dose-dependent inhibition of the cell viability of HT-29 cells by inducing apoptosis, as evidenced by the accumulation of the sub-G1 cell population stained by PI, as well as the ladder-like DNA fragmentation in a dose-dependent manner. S. quelpaertensis-inducing apoptosis was accompanied by the induction of S cell cycle arrests, increasing $NO^{\bullet}$ concentrations, and the down-regulation of IAPs, including X-chromosome-linked IAP (XIAP), cellular IAP-1 (cIAP-1), cIAP-2, and survivin. Taken together, these findings have important implications for future clinical developments of S. quelpaertensis in colon cancer treatment.

• Molecules and Cells
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• v.37 no.11
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• pp.785-794
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• 2014

Mitophagy, a cellular process that selectively targets dysfunctional mitochondria for degradation, is currently a hot topic in research into the pathogenesis and treatment of many human diseases. Considering that hypoxia causes mitochondrial dysfunction, which results in cell death, we speculated that selective activation of mitophagy might promote cell survival under hypoxic conditions. In the present study, we introduced the Regulator of calcineurin 1-1L (Rcan1-1L) to initiate the mitophagy pathway and aimed to evaluate the effect of Rcan1-1L-induced mitophagy on cell survival under hypoxic conditions. Recombinant adenovirus vectors carrying Rcan1-1L were transfected into human umbilical vein endothelial cells and human adult cardiac myocytes. Using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide MTT assay and Trypan blue exclusion assay, Rcan1-1L overexpression was found to markedly reverse cell growth inhibition induced by hypoxia. Additionally, Rcan1-1L overexpression inhibited cell apoptosis under hypoxic conditions, as detected by annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) apoptosis assay. Meanwhile, the mitochondria-mediated cell apoptotic pathway was inhibited by Rcan1-1L. In contrast, knockdown of Rcan1-1L accelerated hypoxia-induced cell apoptosis. Moreover, Rcan1-1L overexpression significantly reduced mitochondrial mass, decreased depolarized mitochondria, and downregulated ATP and reactive oxygen species production. We further delineated that the loss of mitochondrial mass was due to the activation of mitophagy induced by Rcan1-1L. Rcan1-1L overexpression activated autophagy flux and promoted translocation of the specific mitophagy receptor Parkin into mitochondria from the cytosol, whereas inhibition of autophagy flux resulted in the accumulation of Parkin-loaded mitochondria. Finally, we demonstrated that mitochondrial 1permeability transition pore opening was significantly increased by Rcan1-1L overexpression, which suggested that Rcan1-1L might evoke mitophagy through regulating mitochondrial permeability transition pores. Taken together, we provide evidence that Rcan1-1L overexpression induces mitophagy, which in turn contributes to cell survival under hypoxic conditions, revealing for the first time that Rcan1-1L-induced mitophagy may be used for cardioprotection.

• Korean Journal of Materials Research
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• v.3 no.2
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• pp.175-184
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• 1993

Abstract Co-and/or AI-added Nd-Fe-B-based magnetic alloys were fabricated by using vacuum induction melting frunace, and melt-spun ribbons were made of the magnetic alloys with single roll rapid quenching method. The variation of magnetic properties of the melt-spun ribbons as a function of Cuwheel velocity (Vs) were investigated. Bonded magnets were made of the optimally quenched ribbon fragments, and the magnetic properties of the melt-spun ribbons and the bonded magnets were studied, relating to the microstructure and crystalline structure. Cu-wheel surface velocity had a strong effect on the magnetic properties of the melt-spun ribbons, and the maximum properties were obtained around Vs =20m/sec. The optimally quenched ribbon had a cellura-type microstructure, in which fine N$d_2$F$e_14$B grains were surrounded by thin Nd-rich phase. In case of a 2.1at% AI-added melt-spun ribbon, the magnetic properties were as follows: iHc, Br, and (BH)max were 15.5KOe, 7.8KG and 8.5MGOe respectively. And resin bonded magnets were fabricated by mixing optimally quenched ribbon fragments with 2.5wt % polyamide resin, compacting and binding at room temperature. The iHc, Br and (BH)max of bonded magnet were lO.2KOe, 4.4KG and 3.3MGOe respectively. And hot-pressed magnets were made by pressing the overquenched ribbons at high temperature. The magnetic properties of hot-pressed magnets were better than those of bonded magnets, and when the holding time was 8 minutes, the iHc, Br, and (BH)max of the hot-pressed magnet were 1O.8KOe, 7.3KG and 8.0MGOe respectively. Domain structure was mainly maze pattern, which means that the easy magnetization axis could be aligned, and the domain width of the hot-pressed magnets was smaller than that of bonded magnets.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.282-288
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• 2008

Tissue ischemia resulting from the constriction or obstruction of blood vessels leads to an illness that may affect many organs including the heart, brain, and legs. In recent years, considerable progress has been made in the field of therapeutic angiogenesis and the new approaches are expected to cure those "no-option patients" who are unsuited to conventional therapies. Although single angiogenic growth factor may be successful in inducing angiogenesis, combination of multiple growth factors is increasingly sought these days to augment the therapeutic responses. This trend is proper in light of the fact that blood vessel formation is a complex and multi-step process that requires the actions of many different factors. To meet the growing need for functionally significant blood flow recovery in the ischemic tissues, a novel strategy that can provide concerted actions of multiple factors is required. One way to achieve such a goal is to use a transcription factor that can orchestrate the expression of multiple target genes in the ischemic region and thus induce significant level of angiogenesis. Here, a putative transcription factor, cardiac ankyrin repeat protein (CARP), was evaluated in adenoviral vector context for angiogenic activity in human umbilical vein endothelial cells. The results indicated significant increase in proliferation, capillary-like structure formation, and induction of vascular endothelial growth factor, a typical angiogenic gene. Taken together, these results suggest that CARP represents itself as a novel target for therapeutic angiogenesis and warrants further investigation.