• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.1951-1957
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• 2007

A new synthetic strategy based on the acid-base catalyzed sol-gel method was developed for the preparation of a series of mesoporous TiO2 nanoparticles. A key feature of the method involves a gradual change in pH (0.8- 9) during the sol-gel transition, which guarantees easy introduction of mesoporosity without relying on the well-established sonochemical or template approach. In addition, this method leads to the exclusive formation of the anatase phase stable enough to the calcination temperature up to 600 oC. The physicochemical properties of the particles in the series were characterized by various spectroscopic and analytical techniques such as wide-angle XRD, SAXRD, BET surface area, FE-SEM, TEM, FT-IR, TGA, and XPS. The photocatalytic efficiency of these materials was investigated for the oxidation of toluene under UV-irradiation. All but T-ad in the series exhibited high photocatalytic activity pushing the reaction into completion within 3 h. The reaction followed the first order kinetics, and the rate reaches as high as 3.9 × 10?2/min which exceeds the one with the commercially available Degussa P-25 by a factor of 3.2. When comparison is made among the catalysts, the reactivity increases with increase in the calcination temperature which in turn increases the crystallinity of the anatase phase, thus revealing the following rate orders: T-3 < T-4 < T-5 < T-6.

• Journal of the Korean Ceramic Society
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• v.43 no.11 s.294
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• pp.688-692
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• 2006

Ferroelectric lanthanides-substituted $Bi_4Ti_3O_{12}$ $(Bi_{4-x}Ln_xTi_3O_{12}, BLnT)$ thin films approximately 200 nm in thickness were deposited by metal organic chemical vapor deposition onto Pt(111)/Ti/SiO$_2$/Si(100) substrates. Many researchers reported that the lanthanides substitution for Bi in the pseudo-perovskite layer caused the distortion of TiO$_6$ octahedron in the a-b plane accompanied with a shift of the octahedron along the a-axis. In this study, the effect of lanthanides (Ln=Pr, Eu, Gd, Dy)-substitution and crystallization temperature on their ferroelectric properties of bismuth titanate $(Bi_4Ti_3O_{12}, BIT)$ thin films were investigated. As BLnT thin films were substituted to lanthanide elements (Pr, Eu, Gd, Dy) with a smaller ionic radius, the remnant polarization (2P$_r$) values had a tendency to increase and made an exception of the Eu-substituted case because $Bi_{4-x}Eu_xTi_3O_{12}$ (BET) thin films had the smaller grain sizes than the others. In this study, we confirmed that better ferroelectric properties can be expected for films composed of larger grains in bismuth layered peroskite materials. The crystallinity of the thin films was improved and the average grain size increased as the crystallization temperature,increased from 600 to 720$^{\circ}C$. Moreover, the BLnT thin film capacitor is characterized by well-saturated polarization-electric field (P-E) curves with an increase in annealing temperature. The BLnT thin films exhibited no significant degradation of switching charge for at least up to $1.0\times10^{11}$ switching cycles at a frequency of 1 MHz. From these results, we can suggest that the BLnT thin films are the suitable dielectric materials for ferroelectric random access memory applications.

• Journal of Ginseng Research
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• v.43 no.1
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• pp.49-57
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• 2019

Background: Korean Red Ginseng (KRG; Panax ginseng Meyer) is a widely used medicinal herb known to exert various immune modulatory functions. KRG and one of its purified components, ginsenoside Rg3, are known to possess anti-inflammatory activities. How they impact helper T cell-mediated responses is not fully explored. In this study, we attempted to evaluate the effect of KRG extract (KRGE) and ginsenoside Rg3 on Th1 cell responses. Methods: Using well-characterized T cell in vitro differentiation systems, we examined the effects of KRGE or enhanced Rg3 on the Th1-inducing cytokine production from dendritic cells (DC) and the naïve $CD4^+$ T cells differentiation to Th1 cells. Furthermore, we examined the change of Th1 cell population in the intestine after treatment of enhanced Rg3. The influence of KRGE or enhanced Rg3 on Th1 cell differentiation was evaluated by fluorescence-activated cell sorting, enzyme-linked immunosorbent assay, and quantitative real-time polymerase chain reaction. Results: KRGE significantly inhibited the production level of IL-12 from DCs and subsequent Th1 cell differentiation. Similarly, enhanced Rg3 significantly suppressed the expression of interferon gamma ($IFN{\gamma}$) and T-bet in T cells under Th1-skewing condition. Consistent with these effects in vitro, oral administration of enhanced Rg3 suppressed the frequency of Th1 cells in the Peyer's patch and lamina propria cells in vivo. Conclusion: Enhanced Rg3 negatively regulates the differentiation of Th1 cell in vitro and Th1 cell responses in the gut in vivo, providing fundamental basis for the use of this agent to treat Th1-related diseases.

• Toxicological Research
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• v.28 no.3
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• pp.159-164
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• 2012

Allergic skin inflammation such as atopic dermatitis (AD) is characterized by edema and infiltration with various inflammatory cells such as mast cells, basophils, eosinophils and T cells. Thymic stromal lymphopoietin (TSLP) is produced mainly by epidermal keratinocytes, as well as dermal fibroblasts and mast cells in the skin lesions of AD. Omega-3 polyunsaturated fatty acids in fish oil can reduce inflammation in allergic patients. Fermentation has a tremendous capacity to transform chemical structures. The antiinflammatory effects of fish oil have been described in many diseases, but the beneficial effects by which fermented olive flounder oil (FOF) modulates the allergic response is poorly understood. In this study, we produced FOF and tested its ability to suppress the various allergic inflammatory responses. The ability of FOF to modulate the immune system was investigated using a mouse model of AD. The FOF-treated group showed significantly decreased immunoglobulin E (IgE) and histamine in serum. Also, the increased TSLP expression was significantly inhibited in the FOF group; the FOF-treated group was not appreciably different from the hydrocort cream treatment group. In addition, FOF treatment resulted in a smaller spleen size with reduced the thickness and length compared to the induction group. Splenocytes from mice treated with FOF produced significantly less IFN-${\gamma}$, IL-4, T-box transcription factor (T-bet) and GATA binding protein 3 (GATA3) expression compared with the induction group. These results suggest that FOF may be effective in treating the allergic symptoms of AD. 5.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.2
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• pp.380-388
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• 2005

In this study, the immunological effect of a traditional Korea herbal medicine, Sochungyong-tang (SCRT) that has been widely used for the treatment of various immunological disorders including allergic asthma in Korea, was examined in vitro. In our previous study demonstrated that SCRT decreases the expression of IL-4 mRNA, that plays pivotal role in Th2 cell development, while increases $IFN-{\gamma}{\tilde{a}}expression$, which is one of the key cytokines for Th1 lineage development in Th0 condition. That study strongly implies that SCRT can correct Th2 dominant condition directly affecting to the CD4+ T cell development. Present study designated to further evaluate the SCRT on helper T cell development by monitoring Th1/Th2 specific cytokine secretion patterns in artificially induced Th1 or Th2 polarized condition. The results demonstrated that Th2 cells were dramatically under-populated in Th2 driven condition with SCRT treatment, while Th1 cells were not altered in Th1 skewed condition. Furthermore, under Th2-skewed conditions the levels of and IL-4 were considerably decreased with SCRT treatment. However, the expression of GATA-3, a transcription factor that plays pivotal role in Th2 lineage programming, was not changed with SCRT, suggesting that the suppression of Th2 cell development by SCRT was not mediated by GATA-3. Present study implies that the effect on CD4+ T cell may be the one of key pharmacological effect point for treating IgE medicated allergic asthma by SCRT. These results also suggest that SCRT might be desirable agent for the correction of Th2 dominant pathological disorders.

• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.520-525
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• 2014

In this paper, the effect of silane-treated silicas and epoxidized soybean oil (ESBO) addition on adhesion properties of silicas-filled epoxy adhesives was examined. The silicas were treated by ${\gamma}$-methacryloxy propyltrimethoxy silane (MPS), ${\gamma}$-glycidoxy propyl trimethoxy silane (GPS), and ${\gamma}$-mercapto propyl trimethoxy silane (MCPS). Surface and structural properties of the adhesives were determined by using scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FT-IR). The t-peel strength of the adhesives was estimated using the universal testing machine (UTM). And, the equilibrium spreading pressure, surface free energy, and specific surface area were investigated by BET methods with $N_2$/77 K adsorption. As a result, the peel strength of the adhesives was increased in the presence of silane-treated silicas in the adhesives compared to that of untreated silicas. This result indicated that the silane coupling agent played an important role in improving the dispersion of silicas in epoxy adhesives. And, the adhesives treated by MCPS were superior to the others in adhesion.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.737-741
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• 2005

In this study, the effect of copper content on the NO removal efficiency by Cu/MCM-41 has been investigated. MCM-41 was prepared by hydrothermal synthesis using a gel mixture of colloidal silica solution and cetyltrimethylammonium. Cu/MCM-41 was manufactured with copper content (5, 10, 20, and 40%) in Cu(II) acetylacetonate. The surface properties of MCM-41 were investigated by using pH, XRD, and FT-IR analyses. $N_2/77K$ adsorption isotherm characteristics, including the specific surface area and micropore volume were studied by BET's equation and Boer's t-plot methods. NO removal efficiency was confirmed by gas chromatography technique. From the experimental results, the MCM-41 was analyzed to have the surface functional groups of Si-OH and Si-O-Si and the characteristic diffraction lines (100), (110), (200), and (210) corresponding to a hexagonal arrangement structure. The copper content supported on MCM-41 appeared to increase the NO removal efficiency in spite of decreasing the specific surface areas or micropore volumes. Consequently, it was found that the copper content in Cu/MCM-41 played an important role in improving the NO removal efficiency, which was mainly attributed to the catalytic reactions.

• Journal of the Korean Society of School Health
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• v.16 no.1
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• pp.135-148
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• 2003

The purpose of this study was to find out the degree of satisfaction of body image and sex-role identity of primary school boys and girls and to examine their relevance between two sex groups. The data from study would be useful for mapping out some measures for school health education. Two hundred and forty five(245) students of 6th grade from 5 different primary schools in Seoul city and Gyonggi Province were selected for the study. The meaningful difference among demographic sociological characteristics between boys and girls has been shown to be in religion($x^2$=6.705, p=.044), the order of siblings($x^2$=7.455, p=.024), mother's academic career ($x^2$=6.705, p=.035) and the levels of living ($x^2$=4.108, p=.043). In the frequency distribution of sex-role identity, boys and girls were revealed as : undifferentiated 41.0%, 36.4%; as androgynous 24.8%, 25.8% respectively. Boys have masculinity (23.1%), on the other hand girls more feminity (22.7%). The meaningful difference of the degree of satisfaction of body image depends on father's ag(t=3.029, p=.050), mother's occupation(t=2.878, p=.023), home atmosphere(t=9.056, p=.000), level of livin(t=2.216, p=.028), academic achievements(t=4.580, p=.011). Masculine sex-role identity has shown its meaningful difference in mother's academic background(t=7.042, p=.001), academic achievements(t=14.963, p=.000). Feminine sex-role identity according to general characteristics shows meaningful difference in gender(t=2.683, p=.008), the order of siblings(t=3.019, p=0.51), father's academic career(t=5.558, p=.004) mother's academic background(t=7.676, p=.001), mother's occupation (t=3.405, p=.010), home atmosphere(t=4.492, p=.012), school performance(t=16.774, p=.000). Sex-role identity influences on the degree of satisfaction of body image as the relation bet ween the degree of satisfaction of body image and sex-role identity is pro correlative.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.1-8
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• 2010

Inonotus obliquus is one of the immune-regulatory substances and is recognized to play the role in the metabolic process of inflammation, allergy and immuntiy. The purpose of this study was to evaluate the effects of water extracts of Inonotus obliquus (IOW) on the liver lymphocyte immune function in the Sprague-Dawley male rats treated with carbon tetrachloride ($CCl_4$) to induce liver damage. Rats were fed with each experimental diet and water for 4 weeks. We found that effects of IOW on interferon-gamma (IFN-$\gamma$), signal transducer and activator of transcription 1 (STAT1), phospho-signal transducer and activator of transcription 1 (pSTAT1) and GATA-binding protein 3 (GATA-3) were decrease in vivo. Interleukin-4 (IL-4), STAT6, pSTAT6 and T-box expressed in T-cells (T-bet) decreased significantly lower in $CCl_4$+IOW group than the $CCl_4$ group. Our data indicated that cytokine protein production were increased in $CCl_4$ group and $CCl_4$+IOW group. As a result of this study, we assume that IOW fed could regulate the immuno-modulating functions through regulate the cytokine production capacity activated by liver damage.

• BMB Reports
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• v.45 no.2
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• pp.79-84
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• 2012

In asthma, T helper 2 (TH2)-type cytokines such as interleukin (IL)-4, IL-5, and IL-13 are produced by activated $CD^{4+}$ T cells. Dendritic cells played an important role in determining the fate of naive T cells into either $T_H1$ or $T_H2$ cells. We determined whether RG-II regulates the $T_H1/T_H2$ immune response by using an ovalbumin-induced murine model of asthma. RG-II reduced IL-4 production but increased interferon-gamma production, and inhibited GATA-3 gene expression. RG-II also inhibited asthmatic reactions including an increase in the number of eosinophils in bronchoalveolar lavage fluid, an increase in inflammatory cell infiltration in lung tissues, airway luminal narrowing, and airway hyperresponsiveness. This study provides evidence that RG-II plays a critical role in ameliorating the pathogenic process of asthmatic inflammation in mice. These findings provide new insights into the immunotherapeutic role of RG-II in terms of its effects in a murine model of asthma.