• Asian-Australasian Journal of Animal Sciences
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• v.29 no.2
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• pp.288-298
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• 2016

Resveratrol acts as a free radical scavenger and a potent antioxidant in the inhibition of numerous reactive oxygen species (ROS). The function of resveratrol and resveratrol-loaded nanoparticles in protecting human lung cancer cells (A549) against hydrogen peroxide was investigated in this study. The 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) assay was performed to evaluate the antioxidant properties. Resveratrol had substantially high antioxidant capacity (trolox equivalent antioxidant capacity value) compared to trolox and vitamin E since the concentration of resveratrol was more than $50{\mu}M$. Nanoparticles prepared from ${\beta}$-lactoglobulin (${\beta}$-lg) were successfully developed. The ${\beta}$-lg nanoparticle showed 60 to 146 nm diameter in size with negatively charged surface. Non-cytotoxicity was observed in Caco-2 cells treated with ${\beta}$-lg nanoparticles. Fluorescein isothiocynate-conjugated ${\beta}$-lg nanoparticles were identified into the cell membrane of Caco-2 cells, indicating that nanoparticles can be used as a delivery system. Hydrogen peroxide caused accumulation of ROS in a dose- and time-dependent manner. Resveratrol-loaded nanoparticles restored $H_2O_2$-induced ROS levels by induction of cellular uptake of resveratrol in A549 cells. Furthermore, resveratrol activated nuclear factor erythroid 2-related factor 2-Kelch ECH associating protein 1 (Nrf2-Keap1) signaling in A549 cells, thereby accumulation of Nrf2 abundance, as demonstrated by western blotting approach. Overall, these results may have implications for improvement of oxidative stress in treatment with nanoparticles as a biodegradable and non-toxic delivery carrier of bioactive compounds.

• Microbiology and Biotechnology Letters
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• v.46 no.2
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• pp.120-126
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• 2018

As a basic study for environment-friendly production of bacterial cellulose (BC) dressing with antimicrobial activity, we isolated and identified acetic acid bacteria which are resistant to silver ions and can biosynthesize silver nanoparticles. Furthermore, conditions of BC production by selected strain were also investigated. Strain G7 isolated from decayed grape skin was able to grow in the presence of 0.1 mM $AgNO_3$ which was identified as Acetobacter intermedius based on 16S rRNA gene analysis. BC production was the highest in a medium containing 2% glucose as a carbon source, 2% yeast extract as a nitrogen source, and 0.115% acetic acid as a cosubstrate. Structural properties of BC produced in optimal medium were studied using Fourier-transform infrared spectroscopy and X-ray diffractometer, and it was found that BC produced was cellulose type I that was the same as a typical native cellulose. When strain G7 was cultured in an optimal medium containing 0.1 mM $AgNO_3$, the color of the culture broth turned into reddish brown, indicating that silver nanoparticles were formed. As a result of UV-Vis spectral analysis of the culture, it was found that a unique absorption spectrum of silver nanoparticles at 425 nm was also observed. Scanning electron microscopic observations showed that silver nanoparticles were formed on the surface and pores of BC membrane.

• The Korean Journal of Physiology and Pharmacology
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• v.12 no.4
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• pp.177-183
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• 2008

The layers of keratinocytes form an acid mantle on the surface of the skin. Herein, we investigated the effects of acidic pH on the membrane current and $[Ca^{2+}]_c$ of human primary keratinocytes from foreskins and human keratinocyte cell line (HaCaT). Acidic extracellular pH ($pH_e{\leq}5.5$) activated outwardly rectifying $Cl^-$ current ($I_{Cl,pH}$) with slow kinetics of voltage-dependent activation. $I_{Cl,pH}$ was potently inhibited by an anion channel blocker 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid (DIDS, 73.5% inhibition at 1${\mu}$M). $I_{Cl,pH}$ became more sensitive to $pH_e$ by raising temperature from $24^{circ}C$ to $37^{circ}C$. HaCaT cells also expressed $Ca^{2+}$-activated $Cl^-$ current ($I_{Cl,Ca}$), and the amplitude of $I_{Cl,Ca}$ was increased by relatively weak acidic $pH_e$ (7.0 and 6.8). Interestingly, the acidic $pH_e$ (5.0) also induced a sharp increase in the intracellular [$Ca^{2+}$] (${\triangle}[Ca^{2+}]_{acid}$) of HaCaT cells. The ${\triangle}[Ca^{2+}]_{acid}$ was independent of extracellular $Ca^{2+}$, and was abolished by the pretreatment with PLC inhibitor, U73122. In primary human keratinocytes, 5 out of 28 tested cells showed ${\triangle}[Ca^{2+}]_{acid}$. In summary, we found $I_{Cl,pH}$ and ${\triangle}[Ca^{2+}]_{acid}$ in human keratinocytes, and these ionic signals might have implication in pathophysiological responses and differentiation of epidermal keratinocytes.

• Korean Journal of Veterinary Research
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• v.38 no.2
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• pp.345-352
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• 1998

The diagnosis of brucellosis is currently based on serological and microbiological tests. However, the microbiological isolation and identification have several disadvantages such as time-consuming and laborious, and the serological methods have been reported to cross-react with antigens other than those from Brucella spp. To develop a sensitive and rapid diagnostic method for detection of Brucella species, the genus-specific primers were designed and synthesized from the sequence of gene encoding a 31kDa cell surface protein(BCSP) and a 36kDa outer membrane protein(OMPB) of B abortus. The amplified 711bp and 982bp DNA fragments were only visible in each species of Brucella by PCR method using the BCSP and OMPB primers, respectively. However, PCR product was not obtained with DNA from other Gram-negative bacteria. As little as 1pg of the B abortus genomic DNA could be detected by this PCR method. Using the PCR technique, semen samples from 185 bulls of Brucella-seronegative herds in Cheju island were examined for comparison of this PCR method with conventional methods in 1995. The semen samples from 5 bulls were positive by culture method and PCR, and one was positive and 5 were suspect by semen plasma agglutination test. However, the semen samples obtained from 177 bulls were negative by semen plasma agglutination, culture and PCR methods in 1996. The results of comparison tests suggested that PCR was a better test than agglutination test against semen of bulls. This study indicated that the PCR technique was a valuable for the diagnosis of bovine brucellosis, particulary in bull semens.

• Journal of Acupuncture Research
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• v.29 no.1
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• pp.115-125
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• 2012

Objectives : The purpose of this study is to observe the inhibitory effects of $Chrthami$ semen oil pharmacopuncture(CSOP) on CIA (collagen-induced arthritis) mice. Materials and Methods : Two types of experiments were conducted: $in$ $vitro$ assay, inhibition of MIF mRNA and TNF-${\alpha}$ mRNA expressions in synovial membranes was observed, and $in$ $vivo$ assay, $1{\mu}{\ell}/kg$ CSOP was injected every day to the left $Weizhong$ ($BL_{40}$) from day 3 to 21 after induction of CIA, and changes in paw edema, apical surface morphology, neovascularization in synovial membranes, fibrosis, pro-inflammatory cytokines production, Th-1 differentiation, and anti-inflammatory effect were investigated. Results : 1. In synoviocytes of the CIA mice treated with CSOP, MIF mRNA and TNF-${\alpha}$ mRNA expressions were down-regulated in a dose-dependent manner. 2. Paw edema of the CIA mice treated with CSOP was diminished. 3. Tissue injury in the synovial membranes, capillary distribution and fibrosis were reduced in CSOP-treated mice. 4. MIF, TNF-${\alpha}$, IL-6, MMP-9 expressions were repressed in CSOP-treated mice during the experiment to observe the inhibitory effect on cytokines production in early stage RA. 5. IL-12 and CD28 were reduced in CSOP-treated mice during the observation of inhibitory effect on Th 1 differentiation. 6. PPAR-${\gamma}$ was increased during the experiment to observe the anti-inflammatory effect of CSOP. Conclusions : The results may suggest that administration treatment using $Chrthami$ semen oil pharmacopuncture decreases the inflammatory response on an Animal Model with CIA.

• Journal of the Korean Electrochemical Society
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• v.12 no.4
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• pp.329-334
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• 2009

This study is to develop a fuel cell system applicable to an in situ NMR (Nuclear magnetic resonance) diagnosis. The in situ NMR can be used in real time monitoring of various reactions occurring in the fuel cell, such as oxidation of fuel, reduction of oxygen, transport phenomena, and component degradation. The fuel cell for this purpose is, however, to be operated in a specifically designed tubular shape toroid cavity detector (TCD), which constrains the fuel cell to have a tubular shape. This may cause difficulties in effective mass transport of reactants/products and uniform distribution of assembly pressure. Therefore, a new flow field designed in a particular way is necessary to enhance the mass transport in the tubular fuel cell. In this study, a tubular-shaped close-type flow field made of non-magnetic material is developed. With this flow field, oxygen is effectively delivered to the cathode surface and the produced water is readily removed from the membrane-electrode assembly to prevent flooding. The resulting DMFC (direct methanol fuel cell) outperforms the open-type flow field and exhibits $36\;mW/cm^2$ even at room temperature.

• Journal of Korean Association for Spatial Structures
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• v.4 no.3 s.13
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• pp.65-75
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• 2004

A shell structure, having a curvature with a curved surface, is an extremely efficient mechanical creation regard to the external load. A basic structural resistance mechanism is the structural system, which is resisted the out-of-plane direction load by in-plane forces using the structure's curvature. Therefore, it has a merit to make thin and lightweight large spacial structures using minimum materials. Among the large spare structural system, the rapid development of the membrane structures, cable structures and the hybrid structures are watched recently. But, this kind of structural system shows the unstable phenomenon by snap-through or bifurcation according to the shape of structure, and the understanding of the collapse mechanism by this phenomenon is very important to the design process. In this study, I investigated the unstable characteristics of the Geiger-type, Zetlin-type and flower-type hybrid cable dome structures, which is the lightweight hybrid structures using compression and tension elements continuously, according to the difference of structural system.

• Molecular & Cellular Toxicology
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• v.1 no.2
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• pp.116-123
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• 2005

The application of high pressure on cellular morphology, proliferation and protein expression of Jurkat cells (human T lymphocyte cell line) has been extensively investigated. In the present study, we manufactured a novel pressure chamber that modulates 5% $CO_{2}$, temperature and pressure (up to 3 ATA). Jurkat cells was incubated 2 ATA pressure and analyzed cellular morphology and growth using an electron microscopy and MTT assay. The cells showed the morphological changes in the cell surface, which appeared to cause a severe damage in cell membrane. The growth rate of the cells under 2 ATA pressure decreased as cultured time got increased. Furthermore, a long term exposure of high pressure on Jurkat cells may act as one of the important cellular stresses that leads to inducing cell death. Cellular proteomes were separated by 2-dimensional electrophoresis with pH 3-10 ranges of IPG Dry strips. And many proteins showed significant up-and-down expressions with hyperbaric pressure. Out of all, 10 spots were identified significantly using matrix-assisted laser desorption/ionization-time of fight (MALDI-TOF) mass spectrometry. We and found that 9 protein expressions were decreased and one protein, heat shock protein HSP 60, was increased in Jurkat cells under 2 ATA. Identified proteins were related to lipid metabolism and signal transduction.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.291-298
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• 2016

In this study, zwitterionic surfactants were added to liposome systems at different pH conditions to understand the effect of surfactants on liposome characteristics. For this purpose, amine oxide surfactants having different hydrocarbon chain lengths were synthesized and the structure of the resulting product was elucidated by using $^1H$ NMR, $^{13}C$ NMR, and FT-IR. In addition, the physical properties of newly synthesized surfactants such as critical micelle concentration (CMC), surface tension and isoelectric point were measured. The stability characteristics of liposome systems including average particle sizes and zeta potentials were measured by varying pH and hydrocarbon chain lengths of an amine oxide surfactant. Effects of the pH and hydrocarbon chain length of an amine oxide surfactant on fluidity of a liposome membrane were also examined by measuring the deformability and the binding degree between the surfactant and liposome.

• Applied Chemistry for Engineering
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• v.29 no.5
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• pp.556-564
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• 2018

In this study, polyethylene oxide (PEO)/polyethylene-co-vinyl acetate (EVA)/multi-walled carbon nanotube (MWCNT)-COOH composite membranes were prepared by adding 1, 2, 3, and 5 wt% of MWCNT-COOH to PEO/EVA respectively. The gas permeation properties of $N_2$, $O_2$ and $CO_2$ at $30^{\circ}C$ and 4~8 bar pressure were investigated. In each PEO/EVA/MWCNT-COOH composite membranes, the permeability of $CO_2$ increased with increasing the pressure, but the permeability of $N_2$ and $O_2$ were independent of the feeding pressure. As the MWCNT-COOH content increased, the $CO_2$ permeability increased and then decreased above 2 wt% MWCNT-COOH content. The 2 wt% MWCNT-COOH composite membrane exhibited a $CO_2/N_2$ selectivity of 77.8 and a $CO_2$ permeability of 84 barrer at 8 bar. The high $CO_2/N_2$ selectivity and $CO_2$ permeability were due to the high affinity between the quadrupolar $CO_2$, polar ether groups of PEO, and the polar ester groups of EVA. Additionally, the strong affinity between $CO_2$ and the -COOH groups on the MWCNT surface contributed to the high permeability of $CO_2$.