• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.8
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• pp.52-59
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• 2007

In this paper, we analyzed and measured implant isolation characteristics for a 1.25 Gbps monolithic integrated hi-directional (M-BiDi) optoelectronic system-on-a-chip, which is a key component to constitute gigabit passive optical networks (PONs) for a fiber-to-the-home (FTTH). Also, we derived an equivalent circuit of the implant structure under various DC bias conditions. The 1.25 Gbps M-BiDi transmit-receive SoC consists of a laser diode with a monitor photodiode as a transmitter and a digital photodiode as a digital data receiver on the same InP wafer According to IEEE 802.3ah and ITU-T G.983.3 standards, a receiver sensitivity of the digital receiver has to satisfy under -24 dBm @ BER=10-12. Therefore, the electrical crosstalk levels have to maintain less than -86 dB from DC to 3 GHz. From analysed and measured results of the implant structure, the M-BiDi SoC with the implant area of 20 mm width and more than 200 mm distance between the laser diode and monitor photodiode, and between the monitor photodiode and digital photodiode, satisfies the electrical crosstalk level. These implant characteristics can be used for the design and fabrication of an optoelectronic SoC design, and expended to a mixed-mode SoC field.

• Journal of Life Science
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• v.30 no.4
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• pp.343-351
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• 2020

Sorbus commixta Hedl. has traditionally been used as a remedy for cough, asthma, and other bronchial disorders. In this study, three major triterpenoids-lupeol, β-sitosterol, and ursolic acid and a coumarin, scopoletin, were isolated from a CHCl₃-soluble fragment of the bark of S. commixta. Their structures were identified by spectroscopic analyses, including mass spectrometry (MS), 1D-, and 2D- nuclear magnetic resonance spectroscopy (NMR), as well as by comparing the data with data reported in the literature. Scopoletin was isolated from this plant for the first time. It is a nutraceutical compound contained in many plants that has been reported to exert diverse biological activities, including anti-inflammatory effects. This study examined the inhibitory effect of scopoletin on TNF-α-induced vascular endothelial inflammation. Unlike the marginal impact of other compounds against low-density lipoprotein (LDL) oxidation and vascular endothelial inflammation, scopoletin showed remarkable activity on LDL oxidation (IC₅₀ = 10.2 μM) and exerted vascular anti-inflammatory effects in EA.hy926 human endothelial cells activated by TNF-α. It suppressed the expression of adhesion molecules, such as ICAM-1, VCAM-1, and E-selectin, and blocked the adhesion between THP-1 monocytes and EA. hy926 endothelial cells. It also inhibited TNF-α-induced NF-κB translocation from the cytosol to the nucleus. Moreover, IκBα phosphorylation, which was increased by TNF-α treatment, was reduced after treatment with scopoletin. Thus, scopoletin inhibited TNF-α-induced vascular inflammation in endothelial cells by suppressing the NF-κB signaling pathway. These results demonstrate that owing to its anti-inflammatory activity in the vascular endothelium, scopoletin has the potential to inhibit atherosclerosis development.

• Journal of Life Science
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• v.27 no.10
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• pp.1199-1206
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• 2017

The lymphotoxin ${\beta}$ receptor ($LT{\beta}R$), a member of the tumor necrosis factor receptor family, plays an important role in lymphoid tissue's architecture and organogenesis. We found that $LT{\beta}R$ stimulation induced changes in stress fibers (SFs) in fibroblastic reticular cells (FRCs). MLCK and ROCK play critical roles in the regulation of SF formation in cells. The present study was performed to investigate the antifibrotic effects on SF regulation of $LT{\beta}R$ signaling, with a focus on MLCK inhibition. The effect of $LT{\beta}R$ on the SF change was analyzed using immunoblot and fluorescence assays and agonistic $anti-LT{\beta}R$ antibody-treated FRCs. In addition, we checked the level of Rho-guanosine diphosphate (GDP)/guanosine triphosphate (GTP) exchange activity with FRC lysate. Phospho-ezrin proteins acting as membrane-cytoskeleton linkers completely de-phosphorylated in agonistic $anti-LT{\beta}R$ antibody-treated FRCs. The actin bundles rearranged into SFs, where phospho-myosin light chain (p-MLC) co-localized in FRCs. ML7-treated FRCs completely blocked SFs and showed retraction and shrinkage processes comparable to those observed in agonistic $anti-LT{\beta}R$ antibody-treated cells. Inhibition of ROCK activity induced changes in the actin cytoskeleton organization; however, some SFs remained in the cells, while they were completely disrupted by MLCK inhibition with ML7. We showed that the phosphorylation of MLC was completely abolished with $LT{\beta}R$ stimulation in FRCs. When $LT{\beta}R$ was stimulated with the agonistic $anti-LT{\beta}R$ antibody, the Rho-GDP/GTP exchange activity was reduced, however, the activity was not completely abolished. Collectively, the results illustrated that MLCK was potently responsible for the SF regulation triggered via $LT{\beta}R$ signaling in FRCs.

• Journal of Life Science
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• v.29 no.1
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• pp.60-68
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• 2019

Limonium tetragonum, an edible halophyte that grows on salt marshes in Korea, is thought to possess various health benefits (e.g., antioxidant, antitumor, and hepatoprotective). In the present study, different solvent partitioned subfractions, water ($H_2O$), buthanol (n-BuOH), 85% aqueous methanol (85% aq. MeOH), and hexane (n-hexane), from crude extract of L. tetragonum were tested for their ability to prevent adipogenesis in differentiating 3T3-L1 preadipocytes. The treatment of differentiating 3T3-L1 preadipocytes with L. tetragonum subfractions (LTFs) resulted in suppressed adipogenesis and reduced expression of adipogenesis-related transcription factors such as peroxisome proliferator-activated receptor gamma ($PPAR{\gamma}$), CCAATT/enhancer-binding protein alpha ($C/EBP{\alpha}$), and sterol regulatory element-binding protein 1c (SREBP-1c) at both mRNA and protein levels. In addition, the LTF treatment notably decreased the levels of phosphorylated p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK) of the mitogen-activated protein kinase (MAPK) pathway in association with $PPAR{\gamma}$-linked adipogenesis. Among all the tested LTFs, $H_2O$ and n-hexane were the most effective in lowering lipid accumulation and regulating the adipocyte differentiation via $PPAR{\gamma}$ pathway. Taken together, the results indicated that the $H_2O$ and n-hexane LTFs contain bioactive compounds that may exhibit significant antiadipogenesis activity by downregulation of the $PPAR{\gamma}$ pathway and inactivation of the MAPK signal pathway in 3T3-L1 preadipocytes.

• Korean Journal of Clinical Laboratory Science
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• v.51 no.2
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• pp.245-251
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• 2019

This study examined the effects of 2-methoxy-1,4-naphthoquinone (MQ) on the monocyte chemoattractant protein-1 (MCP-1)-induced migration of monocytes, which is an important phenomenon for the body defense and immune response. MQ is a major component extracted from Impatiens balsamina leaves, which have been used for many years in Asian medicine for the treatment of a range of diseases and pain. The cytotoxicity of MQ began to appear at a concentration of $10{\mu}M$, and approximately 50% cytotoxicity was confirmed at $100{\mu}M$. The MCP-1 induced migration of the THP-1 monocyte cell line increased after MQ treatment in a dose dependent manner and the largest increase was observed at $0.1{\mu}M$. The level of cAMP expression decreased after a treatment with $0.1{\mu}M$ MQ. The phosphorylation of extracellular signal-regulated kinases 1/2 (Erk1/2), a key signaling protein involved in the signaling pathway of C-C motif chemokine receptor 2 (CCR2), a receptor for MCP-1, was increased by the simultaneous treatment of $0.1{\mu}M$ MQ. These results show that MQ increases the MCP-1-induced migration of THP-1, decreases the level of cAMP expression, and increases the level of Erk1/2 phosphorylation.

• Journal of Life Science
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• v.31 no.1
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• pp.17-27
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• 2021

This study was performed to investigate the antioxidant activities of subfractions of Peucedanum insolens Kitagawa root in various organic solvents and their anti-inflammatory effects on LPS-treated RAW264.7 cells. First, P. insolens Kitagawa roots were dried at room temperature for one week, chopped, and extracted with 70% ethanol. The resulting extracts were successively sub-fractionated with hexane, chloroform, ethyl acetate, and water. The antioxidant potential of the fractions was evaluated using a DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging assay and by measuring total polyphenol and flavonoid contents. The anti-inflammatory potency of the fractions was evaluated by measuring the inhibition levels of the expressions of inflammatory-mediated genes and proteins (e.g., iNOS, COX-2, IL-1β, and IL-6) in RAW264.7 cells. The results clearly showed that the ethyl acetate fraction of the P. insolens Kitagawa root contained relatively high total flavonoid (34.08±1.68 ㎍ of quercetin equivalents per mg) and total polyphenol (154.1±3.2 ㎍ of gallic acid equivalents per mg) contents. The DPPH assay results showed that the P. insolens Kitagawa root possessed strong free radical scavenging activity in the ethyl acetate fraction. Both the ethyl acetate and hexane fractions showed strong inhibitory potencies to nitric oxide production induced by lipopolysaccharide (1 ㎍/ml) treatment for 24 hr in RAW264.7 cells. The results also showed that both the hexane and ethyl acetate fractions of the P. insolens Kitagawa root strongly inhibited mRNA levels of iNOS, IL-1β, and IL-6, which were overexpressed by LPS treatment for 24 hr in the RAW264.7 cells. These results suggest that P. insolens Kitagawa root may contain compounds that possess strong potency for anti-inflammatory activity. Further studies are needed to discover more detailed modes of action of P. insolens Kitagawa root fractions against inflammation modulation, such as the regulation of cytokine signaling and inflammatory signaling pathways.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.565-573
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• 2022

Gingival inflammation is one of the main causes that can be related to various periodontal diseases. Human gingival fibroblast (HGF) is the major constituent in periodontal connective tissue and secretes various inflammatory mediators, such as nitric oxide (NO) and prostaglandin E₂ (PGE₂), upon lipopolysaccharide stimulation. This study is aimed at investigating the anti-inflammatory and antioxidative activities of Lotus Root extract (LRE) in Porphyromonas gingivalis derived lipopolysaccharide (LPS-PG)-stimulated HGF-1 cells. The concentration of NO and PGE₂, as well as their responsible enzymes, inducible NO synthase (iNOS), and cyclooxygenase-2 (COX-2), was analyzed by Griess reaction, ELISA, and western blot analysis. LPS-PG sharply elevated the production and protein expression of inflammatory mediators, which were significantly attenuated by LRE treatment in a dose-dependent manner. LRE treatment also suppressed activation of Toll-like receptor 4 (TLR4)/myeloid differentiation primary response gene 88 (MyD88) and nuclear factor-κB (NF-κB) in LPS-PG-stimulated HGF-1 cells. In addition, one of phase II enzyme, NAD(P)H quinone dehydrogenase (NQO)-1, and its transcription factor, Nuclear factor erythroid 2-related factor 2 (Nrf2), were significantly induced by LRE treatment. Consequently, these results suggest that LRE ameliorates LPS-PG-induced inflammatory responses by attenuating TLR4/MyD88-mediated NF-κB, and activating NQO-1/Nrf2 antioxidant response element signaling pathways in HGF-1 cells.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.5
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• pp.651-663
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• 2016

Corn silk, Job's tears, Lentinus edodes, and apple peel 70% ethanol extracts (CS, JT, LE, and AP) were studied for their antioxidant activities. CS among all extracts showed the highest antioxidant activities based on total polyphenol and flavonoid contents, 2,2-diphenyl-${\beta}$-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonate) radical scavenging activity, and reducing power. Adipocyte differentiation was investigated by Oil Red O staining assay using CS, JT, LE, AP, and extract of developed bread containing corn silk, Job's tears, Lentinus edodes, and apple peel (DB) treated to 3T3-L1 adipocytes. DB1 and DB2 showed anti-adipogenic and antioxidant effects. Triglyceride (TG) accumulation in 3T3-L1 cells was measured, and among the samples tested (CS, JT, LE, and AP), CS was found to have the highest inhibitory activity against TG accumulation of differentiated 3T3-L1 adipocytes and regulated factors associated with adipogenesis. CS suppressed lipid droplet formation and adipocyte differentiation in 3T3-L1 cells in a dose-dependent manner. We examined the effects of CS on the levels of CCAAT-enhancer-binding protein ${\beta}(C/EBP{\beta})$, peroxisome proliferator activated receptor ${\gamma}(PPAR{\gamma})$, and adipocyte-specific lipid binding protein (aP2) mRNA as well as protein levels in 3T3-L1 cells treated with CS at various concentrations (0, 10, 50, and $100{\mu}g/mL$) during adipocyte differentiation and treatment with CS in 3T3-L1 adipocytes down-regulated expression of $PPAR{\gamma}$ and aP2 mRNA. CS also significantly inhibited up-regulation of $C/EBP{\beta}$, $PPAR{\gamma}$, and aP2 proteins during adipocyte differentiation. These data indicate that DBs have anti-adipogenic activity induced by CS in 3T3-L1 preadipocytes, and CS exerts anti-adipogenic activity by inhibiting expression of $C/EBP{\beta}$, $PPAR{\gamma}$, and aP2 signaling pathway in 3T3-L1 adipocytes. JT, LE, and AP had no inhibitory effects on differentiation of 3T3-L1 preadipocytes but displayed strong antioxidant effects. These results suggest that the developed bread may be a health beneficial food that can prevent or treat obesity and diseases induced by oxidative stress.

• Journal of Life Science
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• v.25 no.9
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• pp.993-999
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• 2015

The beetle Popillia flavosellata has been no reported its functional effects. In this study, we investigated the anti-inflammatory effect of P. flavosellata ethanol extract (PFE) on RAW 264.7 mouse macrophage cells treated with lipopolysaccharide (LPS) for the induction of inflammation. First, we examined the cytotoxicity of PFE in the RAW 264.7 cells at a concentration of 2,000 μg/ml or less. To evaluate the anti-inflammatory effects of PFE, we investigated the expression levels of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6, and proinflammatory enzymes, such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-induced RAW 264.7 cells. In addition, we examined whether PFE inhibited the translocation of nuclear factor kappa B (NF-κB) p65 into the nucleus in the LPS-induced RAW 264.7 cells. We found that the protein levels of TNF-α and IL-6 were decreased in the LPS-induced RAW 264.7 cells after the treatment with PFE in a dose-dependent manner. In addition, we confirmed that PFE inhibited the translocation of NF-κB p65 into the nucleus, as well as the protein expression levels of iNOS and COX-2. Accordingly, we propose that PFE exerts an anti-inflammatory effect through the down-regulation of NF-κB p65, TNF-α, IL-6, iNOS, and COX-2 via the toll like receptor (TLR)-4 inflammatory signaling pathway.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.7
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• pp.1029-1035
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• 2013

The objective of this study was to examine the ability of extracts from Phellinus linteus (PL) and rice with Phellinus linteus mycelium (PLM) to inhibit obesity and diabetes. The efficacy of PL and PLM were evaluated using Oil Red O staining, cholesteryl ester transfer protein (CETP) levels, protein tyrosine phosphate 1B (PTP1B) levels, organ weight, and serum lipid levels. Lipid accumulation significantly decreased by 76% and 59% upon treatment with $300{\mu}g/mL$ of PL and PLM, respectively (P<0.01). The inhibition of CETP activity increased 99% upon treatment with $300{\mu}g/mL$ of PL or PLM. Treatment with 3, 10, 30, 100, and $300{\mu}g/mL$ of PL, changed PTP1B activity by 10, 11, 14, 12, and 18% respectively. Also, treatment with increasing concentrations of PLM led to a significant concentration-dependent inhibition of PTP1B activity (P<0.01). PL and PLM were orally administered for 28 days after a high fat diet (HFD). PL significantly (P<0.05) reduced triglyceride and cholesterol levels. In addition, PLM significantly (P<0.05) reduced triglyceride, cholesterol, and HDL-cholesterol levels. GOT and GPT were not significantly affected. These results indicate that PL and PLM extracts have potent and useful activities for the treatment of obesity and diabetes mellitus.