• Asian Pacific Journal of Cancer Prevention
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• v.13 no.12
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• pp.6017-6022
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• 2012

Background: Resveratrol has been reported to have potential chemopreventive and apoptosis-inducing properties in a variety of tumor cell lines. Objective: In this study, to investigate the effects of resveratrol on protein kinase C (PKC) activity and apoptosis in human colon carcinoma cells, we used HT-29 cells and examined the $PKC{\alpha}$ and ERK1/2 signaling pathways. Methods: To test the effects of resveratrol on the growth of HT-29 cells, the cells were exposed to varying concentrations and assessed with the the MTT cell-viability assay. Fluorescence-activated cell sorter (FACS) analysis was applieded to determine the effects of resveratrol on cell apoptosis. Western blotting was performed to determine the protein levels of $PKC{\alpha}$ and ERK1/2. In inhibition experiments, HT-29 cells were treated with G$\ddot{o}$6976 or PD98059 for 30 min, followed by exposure to $200{\mu}M$ resveratrol for 72 h. Results: Resveratrol had a significant inhibitory effect on HT-29 cell growth. FACS revealed that resveratrol induced apoptosis. Western blotting showed that e phosphorylation of $PKC{\alpha}$ and ERK1/2 was significantly increased in response to resveratrol treatment. Pre-treatment with $PKC{\alpha}$ and ERK1/2 inhibitors (G$\ddot{o}$6976 and PD98059) promoted apoptosis. Conclusion: Resveratrol has significant anti-proliferative effects on the colon cancer cell line HT-29. The PKC-ERK1/2 signaling pathway can partially mediate resveratrol-induced apoptosis of HT-29 cells.

• Journal of the Korean Ceramic Society
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• v.37 no.4
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• pp.395-401
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• 2000

In this study, we chose the basic composition which indicated the best electrical properties by change of x content(0, 0.05, 0.1, 0.15, 0.2, 0.25 mol respectively) in xPb(Mn1/3Sb2/3)O3-(1-x)Pb(Zr0.52Ti0.48)O3 ceramics. And we substituted Cd2+ for Pb2+ site, then observed the sintering behavior, microstructure and electrical propertties according to the various sintering temperature. The basic composition was the 0.05PMS-0.95PZt, and it showed single perovskite phase and excellent properties. In case of Cd2+ substitution, we were able to sinter at 90$0^{\circ}C$ which was lower than conventional sintering temperature(1200~130$0^{\circ}C$). Especially, when the 2mol% substituted PMS-PZT specimens were sintered at 90$0^{\circ}C$ for 2h, we obtained the p=7.6g/㎤, kp=56%, Qm=520 and made sure of a position of Cd2+ substitution by observing lattice parameter, phase transition temperature. From this results, we could infer that because Cd2+ substituted fro A-site, low temperature sintering of Cd2+ substituted PMS-PZT without any loss of electrical properties shows its applicability for the piezoelectric ceramic transformer.

• The Korea Journal of Herbology
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• v.28 no.5
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• pp.21-28
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• 2013

Objectives : The aim of this study was to investigate the neuroprotective effects and mechanisms of Cyperi Rhizoma extracts (CRE) using in vitro and in vivo models of Parkinson's disease (PD). Methods : We evaluated the neuroprotective effect of CRE against 1-methyl-4-phenylpyridinium (MPP+) toxicity using tyrosine hydroxylase immunohistochemistry (IHC) in primary rat mesencephalic dopaminergic neurons. In addition, the effect of CRE was evaluated in mice PD model induced by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). For evaluations, C57bl/6 mice were orally treated with CRE 50 mg/kg for 5 days and were injected intraperitoneally with MPTP (20 mg/kg) at 2 h intervals on the last day. To identify the CRE affects on MPTP-induced neuronal loss of dopaminergic neurons in substantia nigra pars compacta (SNpc) and striatum of mice, the behavioral tests and IHC analysis were carried out. Also, we conducted nitric oxide (NO) and tumor necrosis factor-alpha (TNF-${\alpha}$) assay in dopaminergic neurons and IHC using glial markers in SNpc of mice to assess the anti-inflammation effects. Results : In primary mesencephalic culture system, CRE protected dopaminergic cells against $10{\mu}M$ MPP+-induced toxicity at 0.2 and $1.0{\mu}g/mL$. In the behavior tests, CRE treated group showed improved motor deteriorations than those in the MPTP only treated group. CRE significantly protected striatal dopaminergic damage from MPTP-induced neurotoxicity in mice. Moreover, CRE inhibited productions of NO and TNF-${\alpha}$ in dopaminergic culture system and activation of astrocyte and microglia in SNpc of the mice. Conclusion : We concluded that CRE shows anti-parkinsonian effect by protecting dopaminergic neurons against MPP+/MPTP toxicities through anti-inflammatory actions.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.107-107
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• 2001

During the last decade, enormous progress has been made on the biological significance of apoptosis. Since ras is among the most central molecule in signaling, we asked if ras regulates apoptotic pathway. We have previously shown that H-ras, but not N-ras, induces an invasiveness and motility in human breast epithelial cells (MCF10A), while both H-ras and N-ras induce transformed phenotype. In this study, we wished to seek a chemopreventive agent that effectively induces apoptosis in H-ras-activated cells. Here we show that capsaicin, the major pungent phytochemical in red pepper, induces caspase 3-involved apoptosis selectively in H-ras activated MCF10A cells while the parental MCF10A cells are not effected. In order to study the molecular mechanisms for the increased sensitivity of H-ras MCF10A cells to capsaicin-induced apoptosis, activation of ras downstream signaling molecules, mitogen-activated protein kinases (MAPKinases), upon capsaicin treatment was investigated. Phosphorylated forms of JNK1 and p38 MAPKinase were prominently increased whereas activated ERK-1/2 was decreased by capsaicin in ras-activated cells. The parental cells did not respond to capsaicin, suggesting that capsaicin selectively induces apoptosis through modulating activities of ras downstream signaling molecules in H-ras-activated cells. Studies using chemical inhibitors (CPT-cAMP, SB203580 and PD98059) and dominant negative constructs of JNKl, p38 and MEK show that activation of JNK1 and p38 MAPKinase, but not ERK-1/2, is critical for ras-mediated apoptosis by capsaicin.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.169-175
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• 2018

This study deals with a process for the recovery of hydrogen isotopes from methane ($CQ_4$) and water ($Q_2O$) containing tritium in the nuclear fusion exhaust gas (Q is Hydrogen, Deuterium, Tritium). Steam Methane Reforming and Water Gas Shift reactions are used to convert $CQ_4$ and $Q_2O$ to $Q_2$ and the produced $Q_2$ is recovered by the subsequent Pd membrane. In this study, one circulation loop consisting of catalytic reactor, Pd membrane, and circulation pump was applied to recover H components from $CH_4$ and $H_2O$, one of $CQ_4$ and $Q_2O$. The conversion of $CH_4$ and $H_2O$ was measured by varying the catalytic reaction temperature and the circulating flow rate. $CH_4$ conversion was 99% or more at the catalytic reaction temperature of $650^{\circ}C$ and the circulating flow rate of 2.0 L/min. $H_2O$ conversion was 96% or more at the catalytic reaction temperature of $375^{\circ}C$ and the circulating flow rate of 1.8 L/min. In addition, the amount of $CQ_4$ generated by Korean Demonstration Fusion Power Plant (K-DEMO) in the future was predicted. Then, the treatment process for the $CQ_4$ was proposed and HAZOP (hazard and operability) analysis was conducted to identify the risk factors and operation problems of the process.

• Journal of the Chungcheong Mathematical Society
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• v.21 no.2
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• pp.269-278
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• 2008

Let ${\partial}D$ be the boundary of the open unit disk D in the complex plane and $L^p({\partial}D)$ the class of all complex, Lebesgue measurable function f for which $\{\frac{1}{2\pi}{\int}_{-\pi}^{\pi}{\mid}f(\theta){\mid}^pd\theta\}^{1/p}<{\infty}$. Let P be the orthogonal projection from $L^p({\partial}D)$ onto ${\cap}_{n<0}$ ker $a_n$. For $f{\in}L^1({\partial}D)$, ${\hat{f}}(z)=\frac{1}{2\pi}{\int}_{-\pi}^{\pi}P_r(t-\theta)f(\theta)d{\theta}$ is the harmonic extension of f. Let ${\hat{P}}$ be the composition of P with the harmonic extension. In this paper, we will show that if $1, then ${\hat{P}}:L^p({\partial}D){\rightarrow}H^p(D)$ is bounded. In particular, we will show that ${\hat{P}}$ is unbounded on $L^{\infty}({\partial}D)$.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.133-139
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• 2014

In this research, the photocatalytic degradation of benzothiophene in $TiO_2$ aqueous suspension has been studied. $TiO_2$ photocatalysts are prepared by a sol-gel method. The dominant anatase-structure on $TiO_2$ particles is observed after calcining the $TiO_2$ gel at $500^{\circ}C$ for 1hr. Photocatalysts with various transition metals (Nd, Pd and Pt) loading are tested to evaluate the effect of transition metal impurities on photodegradation. The photocatalytic degradation in most cases follows first-order kinetics. The maximum photodegradation efficiency is obtained with $TiO_2$ dosage of 0.4g/L. The photodegradation efficiency with Pt-$TiO_2$ is higher than pure $TiO_2$ powder. The optimal content value of Pt is 0.5wt.%. Also we investigate the applicability of $H_2O_2$ to increase the efficiency of the $TiO_2$ photocatalytic degradation of benzothiophene. The optimal concentration of $H_2O_2$ is 0.05. The effect of pH is investigated; we obtain the maximum photodegradation efficiency at pH 9. Hydroxy-benzothiophenes and dihydroxy-benzothiophenes are identified as reaction intermediates. It is proposed that benzothiophene is oxidized by OH radical to sequentially form hydroxyl-benzothiophenes, dihydroxybenzothiophenes, and benzothiophenedione.

• Journal of Sensor Science and Technology
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• v.4 no.4
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• pp.16-22
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• 1995

Catalytic combustion type gas sensor was fabricated by using ${\gamma}-Al_{2}O_{3}$, Pd catalyst and some binders for metane and propane detection. Using the gas sensor, digital gas meter was manufactured and tested for sensing performance. The fabricated sensor had power consumption of 700mW with applied voltage of dc 2V and the output voltage of the sensor was about 700mV for propane of 1,000ppm and 500mV for methane of 1,000ppm. In 10 cycle injection of the gases of 2,400ppm, The digital meter showed good sensitivity, linearity, and reproductivity with precision of ${\pm}25ppm({\pm}1%)$.

• Development and Reproduction
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• v.6 no.1
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• pp.1-6
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• 2002

To elucidate the mechanism underlying the embryotropic effect of extracellular matrix(ECM) on the preimplantation development of mammalian embryos, the involvement of mitogen-activated protein kinase(MAPK) downstream the integrin signaling was examined in mouse blastocysts. Blastocysts were cultured in the presence of growth factor-reduced(GFR) Matrigel(0.5％, v/v). MAPK activity was measured by in vitro phosphorylation of myelin basic protein by the Erk1/2 antibody immunoprecipitates of embryonic extract following the Matrigei treatment. MAPK activity of the early blastocysts rapidly increased within 10 min fo1lowing the Matrigel treatment. When the embryos were cultured for 12 h in the presence of Matrigel, the MAPK activity was significantly higher than that ot the control embryos. PD098059, a MAPK kinase(MEK) inhibitor, attenuated the effect of Matrigel on the change in MAPK activity. Taken together, it suggested that the embryotropic effect of ECM proteins might be mediated by the activation of MAPK cascade.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.22 no.2
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• pp.58-62
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• 2022

Pompe disease (PD) is an autosomal recessive genetic disorder caused by a deficiency of the lysosomal enzyme acid α-glucosidase (GAA). It is easy to hastily diagnose as patients if they have two pathogenic variants. Clinical pathologists misdiagnosed our infant and her mother as PD. Here, we report a case of pseudodeficiency in a potential late-onset Pompe disease (LOPD) carrier with a double dual variant, each in cis formation in a 3-month infant. The person who has two pathogenic variants was diagnosed as a carrier, not a patient. It was first reported in Korea. The patient had: two likely pathogenic heterozygous mutations on exon #4: c.752C>T (p.Ser251Leu), c.761C>T (p.Ser254Leu), and a heterozygous mutation on exon #12: c.1726G>A (p.Gly576Ser), also with a heterozygous mutation on exon #15: c.2065G>A (p.Glu689Lys). By presenting this case we emphasize the possibility of cis formation of genes which may cause pseudodeficiency, and potential LOPD carrier form. Hereby we suggest that thorough evaluation of GAA gene is essential among whom initially diagnosed as PD.