• Proceedings of the IEEK Conference
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• 2002.06a
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• pp.167-170
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• 2002

The design and fabrication of Q-band 3-stage monolithic microwave integrated circuit(MMIC) driver and power amplifiers for WLAN are presented using 0.2${\mu}{\textrm}{m}$ AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor(PHEMT). In each stage of the MMIC DA, a negative feedback is used for both broadband and good stability. The MMIC PA has employed a balanced configuration to overcome these difficulties and achieve high power with low VSWR over a wide frequency range. In the MMIC DA, the measurement results arc achieved as an input return loss under -4dB, an output return loss under -l0dB, a gain of 14dB, and a PldB of 17dB at C-band(36~ 44GHz). The chip size is 28mm$\times$1.3mm. The developed MMIC PA has the l0dB linear gain over 360Hz to 420Hz band and 22dBm PldB performance at 400Hz. The size of fabricated MMIC PA is 4mm x3mm. These results closely match with design results. This MMIC DA Sl PA will be used as the unit cells to develop millimeter-wave transmitters for use in wideband wireless LAN systems.

• Journal of Oriental Neuropsychiatry
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• v.18 no.1
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• pp.185-196
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• 2007

Objective : This experimental Study was designed to investigate the effects of FOENICULI FRUCTUS(FF) on the change of inhibition lactate dehydrogenase(LDH) activity in neuronal cells and cytokines production in serum of cerebral ischemic rats. Method : FOENICULI FRUCTUS(FF)freeze dry powder and FF on the LDH activity in neuronal cells. Changes of FF on the physiological parameters(PaO2, PaCO2, MABP and HR) in crerbral ischemic rats. Effects of FF on the IL-1beta production, $TNF-{\alpha}$ production, $TGF-{\beta}$ production, and IL-10 in serum of cerebral ischemic rats. MCAO :. cytokines production of serum by drawing from femoral arterial blood after MCAO 1 hr. Reperfusion : cytokines production of serum by drawing from femoral arterial blood after reperfusion 1 hr. Results and Conclusion : 1. FF did not inhibit lactate dehydrogenase(LDH) activity in neuronal cells. 2. In serum by drawing from femoral arterial blood after middle cerebral arterial occlusion(MCAO) 1 hr and reperfusion 1 hr, sample group was significantly decreased $IL-l{\beta}$ production compared with control group 3. In serum by drawing from femoral arterial blood after MCAO 1 hr and reperfusion 1 hr, sample group was significantly decreased $TNF-{\alpha}$ production compared with control group. 4. In serum by drawing from femoral arterial blood after MCAO 1 hr and reperfusion 1 hr, sample group was significantly increased $TGF-{\beta}$ production compared with control group. 5. In serum by drawing from femoral arterial blood after reperfusion 1 hr, sample group was significantly increased IL-10 production compared with control group. This results were suggested that FF had inhibitive effect on the brain damage by inhibited LDH activity, $IL-l{\beta}$ and $TNF-{\alpha}$production, but accelerated $TGF-{\beta}$ production and IL-10 production.

• Molecules and Cells
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• v.39 no.8
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• pp.594-602
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• 2016

Alkyl hydroperoxide reductase subunit C from Pseudomonas aeruginosa PAO1 (PaAhpC) is a member of the 2-Cys peroxiredoxin family. Here, we examined the peroxidase and molecular chaperone functions of PaAhpC using a site-directed mutagenesis approach by substitution of Ser and Thr residues with Cys at positions 78 and 105 located between two catalytic cysteines. Substitution of Ser with Cys at position 78 enhanced the chaperone activity of the mutant (S78C-PaAhpC) by approximately 9-fold compared with that of the wild-type protein (WT-PaAhpC). This increased activity may have been associated with the proportionate increase in the high-molecular-weight (HMW) fraction and enhanced hydrophobicity of S78C-PaAhpC. Homology modeling revealed that mutation of $Ser^{78}$ to $Cys^{78}$ resulted in a more compact decameric structure than that observed in WT-PaAhpC and decreased the atomic distance between the two neighboring sulfur atoms of $Cys^{78}$ in the dimer-dimer interface of S78C-PaAhpC, which could be responsible for the enhanced hydrophobic interaction at the dimer-dimer interface. Furthermore, complementation assays showed that S78C-PaAhpC exhibited greatly improved the heat tolerance, resulting in enhanced1 survival under thermal stress. Thus, addition of Cys at position 78 in PaAhpC modulated the functional shifting of this protein from a peroxidase to a chaperone.

• Journal of the Korean Vacuum Society
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• v.8 no.4B
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• pp.507-513
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• 1999

8mol%-yttria-stabilized zirconia(YSZ) thin films as oxygen ion conductor were deposited by rf-magnetron sputtering, and the oxygen gas sensors with the structure of $SiO_2$ substrate/Ni-NiO mixed reference layer/Pt/YSZ/Pt were fabricated and their oxygen sensing properties were investigated. The steady-state electro-motive force (EMF) values were measured as a function of oxygen partial pressure ($PO_2;form 1.013\times10^3 \textrm{Pa \;to}\; 1.013\times10^5$Pa) and operating temperature ($300^{\circ}C$ to $700^{\circ}C$). The fabricated YSZ oxygen sensor showed the best oxygen sensing properties at 50$0^{\circ}C$. However, oxygen sensing properties were very low at the temperature lower than 30$0^{\circ}C$ due to the lack of oxygen ion mobility and at the temperature higher than $700^{\circ}C$ due 새 intermixing of materials between the layers. Especially, the YSZ sensor operating at $500^{\circ}C$ and oxygen partial pressure above $1.565\times10^4$Pa showed the oxygen sensing properties close to the values predicted by ideal Nernst equation.

• Korean Journal of Food Science and Technology
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• v.43 no.2
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• pp.213-219
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• 2011

The metastatic effect of Eupatorium japonicum extract (EJE) on MDA-MB-231 human breast cancer cells was investigated. MDA-MB-231 cells were treated with various concentrations of EJE (0, 5, 10 and $20{\mu}g/mL$). EJE inhibited cell migration, invasion and adhesion of MDA-MB-231 cells in dose-dependent manners. Gelatin zymography exhibited that EJE significantly down regulated secretion of matrix metalloproteinase (MMP)-9 and MMP-2. EJE decreased the protein levels of tissue inhibitor of metalloproteinase (TIMP)-1 but increased TIMP-2 levels. Additionally, EJE reduced the protein and mRNA levels of urokinase-type plasminogen activator (uPA), vascular endothelial growth factor (VEGF) and intercellular adhesion molecule (ICAM). In several solvent fractions of EJE, the hexane fraction markedly decreased MDAMB-231 cell migration. Thus, these finding suggest that EJE may be a potential antimetastatic agent, which can considerably inhibit the metastatic and invasive capacity of breast cancer cells.

• Korean Journal of Veterinary Research
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• v.43 no.2
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• pp.211-218
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• 2003

Human ovarian cancerous cells survive in a way that they trigger the nucleotide excision repair (NER) or double-strand DNA repair (dsDNA) repair mechanism to show resistance to anticancer drugs and activate many kinds of repair protein, thus removing damaged DNAs. Two experiments on the PA-1 human ovarian teratocareinoma cell line that hardly has any expression of epidermal growth factor receptor (EGFR) were conducted in the study; first, EGF-R was transfected and its receptor was obtained. The receptor was investigated in terms of its mutual relations with many kinds of protein concerning NER or dsDNA repair. Second, it was examined what kind impact cisplatin and adriamycin had on the effects of EGF-R over the PA-1 cell line lacking EGF-R. When being administered with cisplatin and adriamycin, Hey and Hey C2 cell lines showed a high level of resistance while PA-1 cell line a high level of sensitivity. Hey and Hey C2 cell lines that are resistant against anticancer drugs exhibited a high level of EGF-R expression while PA-1 cell line that is sensitive to them did a much lower level of the expression. When PA-1 cell line was transfected for the expression of DNA adduct and EGF-R, it showed a higher level of resistance compared to the control group. There was no difference in the expression of DNA repair proteins (DNA- dependent protein kinase, Ku70, and Ku80) between Hey and the PA-1 cell lines. The results indicate that the Hey cell line that is resistant against cisplatin and adriamycin works along the signaling system responding to the changes of EGF-R while the PA-1 cell line that is sensitive to both of them does to the lack of EGF-R.

• BMB Reports
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• v.47 no.7
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• pp.376-381
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• 2014

Enzymatic oxidation of pyrogallol was efficiently transformed to an oxidative product, purpurogallin (PPG). Here, the anticoagulant activities of PPG were examined by monitoring activated partial thromboplastin time (aPTT), prothrombin time (PT), and the activities of thrombin and activated factor X (FXa). And, the effects of PPG on expression of plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (t-PA) were evaluated in tumor necrosis factor (TNF)-${\alpha}$ activated human umbilical vein endothelial cells (HUVECs). Treatment with PPG resulted in prolonged aPTT and PT and inhibition of the activities of thrombin and FXa, as well as inhibited production of thrombin and FXa in HUVECs. In addition, PPG inhibited thrombin-catalyzed fibrin polymerization and platelet aggregation. PPG also elicited anticoagulant effects in mice. In addition, treatment with PPG resulted in significant reduction of the PAI-1 to t-PA ratio. Collectively, PPG possesses antithrombotic activities and offers a basis for development of a novel anticoagulant.

• Applied Biological Chemistry
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• v.49 no.1
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• pp.15-20
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• 2006

EDTA is known to have bacteriocidal effect on Vibrio vulnificus, pathogen of septicemia by osmotic shock in seafoods. Attempts were made to elucidate the bacteriocidal effect of phytic acid (PA) as a substitute for EDTA against V. vulnificus and its inhibition effect on the septicemia, which induces liver damage of the mice by the pathogen. Viable cells of V. vulnificus with the initial titre of $1.7{\times}10^6$ c.f.u. $ml^{-1}$ decreased by 90.6% after 1 min and 99.6% after 5 min in distilled water. The titre decreased by 65.9% and 94.5% in 2 mM solution of $Mg^{2+}$. In 0.1 mM solution of PA, the rate of decrease in titre was 97.4% after 1 min of incubation and 99.8% after 5 min, compared to 95.7% and 99.8% in 0.1 mM solution of EDTA. The bacteriocidal effect of PA solution at a concentration of 1 mM was marked: the rate of decrease in titre was 99.9% after 1 min. In relation to the bacteriocidal effect, PA was evaluated as a potential therapeutic agent for V. vulnificus septicemia in mouse. When the survival periods of mice were investigated by PA and EDTA treatment after the pathogen injection, the group of mice which infected by a low concentration of the strain survived longer than that inoculated at high concentration; also, the ratio of survival was 1.3 times higher in PA than in EDTA, showing that the fatal rate depended on the inoculation concentration. Although survival periods of mice induced with liver damage by carbon tetrachloride and then inoculated with the strain showed a similar trend, the fatal rate of mice was 2 times faster than those inoculated with only pathogen into normal liver, These results indicate that the infection by V. vulnificus was more fatal to those with liver disease. Also, symptoms of hemorrhage and inflammation on the mice with induced liver damage were reduced in case there was phytic acid treatment at each concentration.

• Biomolecules & Therapeutics
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• v.25 no.5
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• pp.535-544
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• 2017

Carnosol is a phenolic antioxidant present in rosemary (Rosmarinus officinalis). It is known for anti-inflammatory effects, analgesic activity and anti-cancer effects. However, no study has been dedicated yet to its effect on atopic dermatitis (AD). Here, we show that carnosol effectively inhibited LPS-induced nitric oxide (NO) generation and expression of inflammatory marker proteins (iNOS and COX-2) in RAW 264.7 cells. In addition, carnosol effectively inhibits the phosphorylation of STAT3 and DNA binding activity in RAW 264.7 cells. Pull down assay and docking model analysis showed that carnosol directly binds to the DNA binding domain (DBD) of STAT3. We next examined the anti-atopic activity of carnosol ($0.05{\mu}g/cm^2$) using 5% Phthalic anhydride (PA)-induced AD model in HR1 mice. Carnosol treatment significantly reduced 5% PA-induced AD like skin inflammation in skin tissues compared with control mice. Moreover, carnosol treatment inhibits the expression of iNOS and COX-2 in skin tissue. In addition, the levels of $TNF-{\alpha}$, $IL-1{\beta}$, and Immunoglobulin-E in blood serum was significantly decreased in carnosol treated mice compared with those of 5% PA treated group. Furthermore, the activation of STAT3 in skin tissue was decreased in carnosol treated mice compared with control mice. In conclusion, these findings suggest that carnosol exhibited a potential anti-AD activity by inhibiting pro-inflammatory mediators through suppression of STAT3 activation via direct binding to DBD of STAT3.

• Molecules and Cells
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• v.40 no.10
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• pp.761-772
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• 2017

Glioblastoma is the most frequent and most aggressive brain tumor in adults. Solute carrier family 8 member 2 (SLC8A2) is only expressed in normal brain, but not present in other human normal tissues or in gliomas. Therefore, we hypothesized that SLC8A2 might be a glioma tumor suppressor gene and detected the role of SLC8A2 in glioblastoma and explored the underlying molecular mechanism. The glioblastoma U87MG cells stably transfected with the lentivirus plasmid containg SLC8A2 (U87MG-SLC8A2) and negative control (U87MG-NC) were constructed. In the present study, we found that the tumorigenicity of U87MG in nude mice was totally inhibited by SLC8A2. Overexpression of SLC8A2 had no effect on cell proliferation or cell cycle, but impaired the invasion and migration of U87MG cells, most likely through inactivating the extracellular signal-related kinases (ERK)1/2 signaling pathway, inhibiting the nuclear translocation and DNA binding activity of nuclear factor kappa B ($NF-{\kappa}B$), reducing the level of matrix metalloproteinases (MMPs) and urokinase-type plasminogen activator (uPA)-its receptor (uPAR) system (ERK1/2-$NF-{\kappa}B$-MMPs/uPA-uPAR), and altering the protein levels of epithelial to mesenchymal transitions (EMT)-associated proteins E-cardherin, vimentin and Snail. In addition, SLC8A2 inhibited the angiogenesis of U87MG cells, probably through combined inhibition of endothelium-dependent and endothelium-nondependent angiogenesis (vascular mimicry pattern). Totally, SLC8A2 serves as a tumor suppressor gene and inhibits invasion, angiogenesis and growth of glioblastoma.