Young Hoon Song

Publications of Young Hoon Song

• Alcohol-fermented soybean increases the expression of receptor-interacting protein 2 and IκB kinase β in mouse peritoneal macrophages.

  Authors: Hong-Kun Rim, Kyu-Yeob Kim, Jae-Gyu Ryu, Young-Hoon Song, Hong-Hee Kim, Jong-Hyun Han, Hyun-Ja Jeong, Hyung-Min Kim

  Journal of medicinal food. 09/2011; 14(10):1181-9.

  Soybean is a useful component of traditional Korean medicine with well-documented health-promoting effects. We investigated the effects of alcohol-fermented soybean (AFS) on immune function. When AFSSoybean is a useful component of traditional Korean medicine with well-documented health-promoting effects. We investigated the effects of alcohol-fermented soybean (AFS) on immune function. When AFS treatment was used in combination with recombinant interferon-γ (rIFN-γ), there was a marked cooperative induction of nitric oxide (NO) and tumor necrosis factor (TNF)-α production in mouse peritoneal macrophages. AFS increased the expression of inducible NO synthase mRNA and protein in rIFN-γ-primed macrophages. Treating macrophages with pyrrolidine dithiocarbamate, an inhibitor of nuclear factor-κB (NF-κB), decreased the synergistic effects of AFS. In addition, AFS in combination with rIFN-γ increased the phosphorylation of p38 and c-Jun N-terminal kinase (JNK) but not extracellular signal-regulated kinase. However, AFS had no effect on phosphorylation of mitogen-activated protein kinases by itself. The p38 inhibitor SB203580 or the JNK inhibitor SP600125 inhibited the AFS-induced NO and TNF-α production. When AFS was used in combination with rIFN-γ, there was a co-operative activation of NF-κB and receptor-interacting protein 2 (Rip2)/IκB kinase (IKK)-β. Our results indicate that AFS increases the production of NO and TNF-α through the activation of Rip2/IKK-β in rIFN-γ-primed macrophages.

• Efficient Use of Reforming of Methane With an Arc-Jet Plasma

  Authors: Nakyung Hwang, Young-Hoon Song, Min Suk Cha

  Plasma Science, IEEE Transactions on. 01/2011;

  Carbon dioxide reforming of methane has drawn the attention of many researchers for years, because of both its theoretical yield of hydrogen to carbon monoxide, i.e., H₂/CO = 1, and theCarbon dioxide reforming of methane has drawn the attention of many researchers for years, because of both its theoretical yield of hydrogen to carbon monoxide, i.e., H₂/CO = 1, and the use of greenhouse gas CO₂ . Although catalytic processes have been widely investigated, plasma-based techniques were recently considered, because catalytic processes have problems, such as coking and slow start-up time. However, since there is a lack of concrete information about plasma-induced processes, we systematically tested a dry reforming of methane by using an arc-jet plasma reactor. The effects of supplied power for plasma generation, CO₂/CH₄ ratio, O₂ addition, and the amount of CH₄ + CO₂ in the reactant were experimentally investigated in nitrogen balance. As a result, the H₂/CO ratio of a product can be controlled in the range of 0.8-2.5, and the direction for efficient use of the dry reforming process was proposed. Detailed mechanism and characteristics of the dry reforming of methane were also discussed.

• Emodin inhibits proinflammatory responses and inactivates histone deacetylase 1 in hypoxic rheumatoid synoviocytes.

  Authors: Mi-Kyoung Ha, Young Hoon Song, Soo-Jin Jeong, Hyo-Jung Lee, Ji Hoon Jung, Bonglee Kim, Hyo Sook Song, Jeong-Eun Huh, Sung-Hoon Kim

  Biological & pharmaceutical bulletin. 01/2011; 34(9):1432-7.

  Chronic inflammation of rheumatoid arthritis (RA) is promoted by proinflammatory cytokines and closely linked to angiogenesis. In the present study, we investigated the anti-inflammatory effects ofChronic inflammation of rheumatoid arthritis (RA) is promoted by proinflammatory cytokines and closely linked to angiogenesis. In the present study, we investigated the anti-inflammatory effects of emodin (1,3,8-trihydroxy-6-methyl-anthraquinone) isolated from the root of Rheum palmatum L. in interleukin 1 beta (IL-1β) and lipopolysaccharide (LPS)-stimulated RA synoviocytes under hypoxia. Emodin significantly inhibited IL-1β and LPS-stimulated proliferation of RA synoviocytes in a dose-dependent manner under hypoxic condition. Also, enzyme linked immunosorbent assay (ELISA) revealed that emodin significantly reduced the production of pro-inflammatory cytokines [tumor necrosis factor-alpha (TNF-α), IL-6 and IL-8], mediators [prostagladin E(2) (PGE(2)), matrix metalloproteinase (MMP)-1 and MMP-13] and vascular endothelial growth factor (VEGF) as an angiogenesis biomarker in IL-1β and LPS-treated synoviocytes under hypoxia. Consistently, emodin attenuated the expression of cyclooxygenase 2 (COX-2), VEGF, hypoxia inducible factor 1 alpha (HIF-1α), MMP-1 and MMP-13 at mRNA level in IL-1β and LPS-treated synoviocytes under hypoxia. Furthermore, emodin reduced histone deacetylase (HDAC) activity as well as suppressed the expression of HDAC1, but not HDAC2 in IL-1β and LPS-treated synoviocytes under hypoxia. Overall, these findings suggest that emodin inhibits proinflammatory cytokines and VEGF productions, and HDAC1 activity in hypoxic RA synoviocytes.

• Cell behavior on extracellular matrix mimic materials based on mussel adhesive protein fused with functional peptides.

  Authors: Bong-Hyuk Choi, Yoo Seong Choi, Dong Gyun Kang, Bum Jin Kim, Young Hoon Song, Hyung Joon Cha

  Biomaterials. 12/2010; 31(34):8980-8.

  Adhesion of cells to surfaces is a basic and important requirement in cell culture and tissue engineering. Here, we designed artificial extracellular matrix (ECM) mimics for efficient cellularAdhesion of cells to surfaces is a basic and important requirement in cell culture and tissue engineering. Here, we designed artificial extracellular matrix (ECM) mimics for efficient cellular attachment, based on mussel adhesive protein (MAP) fusion with biofunctional peptides originating from ECM materials, including fibronectin, laminin, and collagen. Cellular behaviors, including attachment, proliferation, spreading, viability, and differentiation, were investigated with the artificial ECM material-coated surfaces, using three mammalian cell lines (pre-osteoblast, chondrocyte, and pre-adipocyte). All cell lines examined displayed superior attachment, proliferation, spreading, and survival properties on the MAP-based ECM mimics, compared to other commercially available cell adhesion materials, such as poly-L-lysine and the naturally extracted MAP mixture. Additionally, the degree of differentiation of pre-osteoblast cells on MAP-based ECM mimics was increased. These results collectively demonstrate that the artificial ECM mimics developed in the present work are effective cell adhesion materials. Moreover, we expect that the MAP peptide fusion approach can be extended to other functional tissue-specific motifs.

• Mussel adhesive protein fused with cell adhesion recognition motif triggers integrin-mediated adhesion and signaling for enhanced cell spreading, proliferation, and survival.

  Authors: Bum Jin Kim, Yoo Seong Choi, Bong-Hyuk Choi, Seonghye Lim, Young Hoon Song, Hyung Joon Cha

  Journal of biomedical materials research. Part A. 03/2010; 94(3):886-92.

  Adhesion of cells to a surface is a basic and important requirement in the fields of cell culture and tissue engineering. Previously, we constructed the cell adhesive, fp-151-RGD, by fusion of theAdhesion of cells to a surface is a basic and important requirement in the fields of cell culture and tissue engineering. Previously, we constructed the cell adhesive, fp-151-RGD, by fusion of the hybrid mussel adhesive protein, fp-151, and GRGDSP peptide, one of the major cell adhesion recognition motifs; fp-151-RGD efficiently immobilized cells on coated culture surfaces with no protein and surface modifications, and apparently enhanced cell adhesion, proliferation, and spreading abilities. In the present study, we investigated the potential use of fp-151-RGD as a biomimetic extracellular matrix material at the molecular level by elucidating its substantial effects on integrin-mediated adhesion and signaling. Apoptosis derived from serum deprivation was significantly suppressed on the fp-151-RGD-coated surface, indicating that RGD-induced activation of integrin-mediated signaling triggers the pathway for cell survival. Analysis of the phosphorylation of focal adhesion kinase clearly demonstrated activation of focal adhesion kinase, a well-established indicator of integrin-mediated signaling, on the fp-151-RGD-coated surface, leading to significantly enhanced cell behaviors, including proliferation, spreading and survival, and consequently, more efficient cell culture.

• The adhesive properties of coacervated recombinant hybrid mussel adhesive proteins.

  Authors: Seonghye Lim, Yoo Seong Choi, Dong Gyun Kang, Young Hoon Song, Hyung Joon Cha

  Biomaterials. 02/2010; 31(13):3715-22.

  Marine mussels attach to substrates using adhesive proteins. It has been suggested that complex coacervation (liquid-liquid phase separation via concentration) might be involved in the highlyMarine mussels attach to substrates using adhesive proteins. It has been suggested that complex coacervation (liquid-liquid phase separation via concentration) might be involved in the highly condensed and non-water dispersed adhesion process of mussel adhesive proteins (MAPs). However, as purified natural MAPs are difficult to obtain, it has not been possible to experimentally validate the coacervation model. In the present work, we demonstrate complex coacervation in a system including recombinant MAPs and hyaluronic acid (HA). Our recombinant hybrid MAPs, fp-151 and fp-131, can be produced in large quantities, and are readily purified. We observed successful complex coacervation using cationic fp-151 or fp-131, and an anionic HA partner. Importantly, we found that highly condensed complex coacervates significantly increased the bulk adhesive strength of MAPs in both dry and wet environments. In addition, oil droplets were successfully engulfed using a MAP-based interfacial coacervation process, to form microencapsulated particles. Collectively, our results indicate that a complex coacervation system based on MAPs shows superior adhesive properties, combined with additional valuable features including liquid/liquid phase separation and appropriate viscoelasticity. Our microencapsulation system could be useful in the development of new adhesive biomaterials, including self-adhesive microencapsulated drug carriers, for use in biotechnological and biomedical applications.

• CF4 decompositions using streamer- and glow-mode in dielectric barrier discharges

  Authors: Yongho Kim, Kwan-Tae Kim, Min Suk Cha, Young-Hoon Song, Seock Joon Kim

  Plasma Science, IEEE Transactions on. 07/2005;

  A Dielectric barrier discharge (DBD) is a promising candidate to remove carbon tetrafluoride (CF₄) because the DBD has been successfully used for generating ozone (O₃) andA Dielectric barrier discharge (DBD) is a promising candidate to remove carbon tetrafluoride (CF₄) because the DBD has been successfully used for generating ozone (O₃) and decomposing nitrogen oxide (NO). A streamer- and glow-mode operations of DBD were carried out in a coaxial cylinder reactor by coupling 10-kHz alternate current (ac) power. The effect of oxygen on the CF₄ decompositions was investigated and the optimum oxygen concentrations were found. We compared N₂-streamer, N₂-glow, and He-glow modes operated in a DBD to investigate the effect of plasma mode on CF₄ removal. The results showed that the most efficient CF₄ removal was obtained in He-glow mode, while N₂-streamer and N₂-glow modes demonstrated similar performances. With a practical point of view, we investigated an optimized geometrical configuration of streamer discharge. A micro hole-size perforated DBD showed significant increases in CF₄ removal efficiency compared to the normal N₂-streamer mode.

• Experimental and numerical analysis of streamers in pulsed corona and dielectric barrier discharges

  Authors: Yongho Kim, Woo Seok Kang, Jin Myung Park, Sang Hee Hong, Young-Hoon Song, Seock Joon Kim

  Plasma Science, IEEE Transactions on. 03/2004;

  Streamer characteristics have been experimentally and numerically analyzed for pulsed-corona discharge (PCD) and dielectric-barrier discharge (DBD) to find out how the discharge methods determineStreamer characteristics have been experimentally and numerically analyzed for pulsed-corona discharge (PCD) and dielectric-barrier discharge (DBD) to find out how the discharge methods determine them and how they, in turn, affect the generation of radicals in flue gases. Experiments have been performed and compared for decomposition of a nitrogen oxide (NO) using PCD and DBD, and the electric field and average electron energy in the streamer are measured in each discharge by using the line ratio of N₂⁺ to N₂^*. The measured results of electron energy reasonably explain in terms of "G-value" how the measured NO removal efficiencies have come out. The PCD having high electron energy turns out to be more efficient for generating N radicals, whereas the DBD containing relatively low electron energy is more effective for producing O radicals. Three-dimensional (3-D) and one-dimensional (1-D) numerical simulations have been carried out to understand the observed streamer dynamics in both the PCD and DBD reactors. The 3-D numerical simulation has successfully illustrated the images of streamer front propagation in a wire-cylinder PCD reactor. In the 1-D simulation for the DBD, the recurrence phenomena of streamers have numerically appeared during the rising phase of an AC voltage. Furthermore, these numerical models have properly predicted the electric fields that are comparable with the corresponding average electron energies estimated from the emission spectral measurements for the PCD and DBD.

• An investigation of the structure and the NO formationcharacteristics of partially premixed methane flames using planar laserinduced fluorescence

  Authors: Min Suk Cha, Wonnam Lee, Young-Hoon Song, Suk Ho Chung

  Lasers and Electro-Optics, 1999. CLEO/Pacific Rim '99. The Pacific Rim Conference on; 02/1999

  The formation of nitric oxide (NO) in hydrocarbon flames has not yet been clearly understood. NO is produced through the thermal NO (Zeldovich mechanism), the N₂O-intermediate mechanismThe formation of nitric oxide (NO) in hydrocarbon flames has not yet been clearly understood. NO is produced through the thermal NO (Zeldovich mechanism), the N₂O-intermediate mechanism and the prompt NO (Fenimore mechanism) in a flame. For partially premixed flames, the thermal NO and the prompt NO mechanism are generally considered as major sources for the total NO, and the amount of NO formed from each of these mechanisms depends on the temperature and the equivalence ratio of the flame. Recent studies suggest that the structure of partially premixed flames and the distribution of CH, OH and NO in flames should be considered in understanding the NO production characteristics. In the present study, the characteristics of NO production in partially premixed methane flames are experimentally investigated using planar LIF imaging techniques

• Plasma-controlled chemistry in plasma reforming of methane

  Authors: Dae Hoon Lee, Kwan-Tae Kim, Min Suk Cha, Young-Hoon Song

  International Journal of Hydrogen Energy.

  Plasma is receiving attention as a prospective tool for the reforming process of obtaining synthesis gas and hydrogen. Although many reports on plasma-induced reforming have been introduced, detailedPlasma is receiving attention as a prospective tool for the reforming process of obtaining synthesis gas and hydrogen. Although many reports on plasma-induced reforming have been introduced, detailed correlations between the reaction paths and plasma parameters remain unclear. Therefore, to figure out the relative role and dominance of plasma-controlled chemistry in the reforming process, we investigate diverse reaction paths in reforming CH4. The arc column length is proposed as a universal process parameter of the plasma-reforming process, and a rationale to support the proposition is provided As a result, the dependence of the reforming process on the arc column length is explained. Three different reaction regimes, defined according to the arc column length and plasma chemistry in each regime, are addressed. The arc column length controls the thermal environment of the reaction and activates different reaction pathways depending on its length. This concept of control also enables the discovery of efficient ways of reforming. The increase in thermal efficiency by controlling the arc column reveals possibilities for optimizing the plasma-induced reforming process.

• Effect of excess oxygen in plasma reforming of diesel fuel

  Authors: Dae Hoon Lee, Kwan-Tae Kim, Min Suk Cha, Young-Hoon Song

  International Journal of Hydrogen Energy.

  This study investigated the plasma reforming process for diesel focusing on the relative ratio of oxygen to fuel. Excess O2 in the partial oxidation process is known to increase the combustionThis study investigated the plasma reforming process for diesel focusing on the relative ratio of oxygen to fuel. Excess O2 in the partial oxidation process is known to increase the combustion portion, resulting in a decreased yield of H2 and CO. However, in this parametric investigation, there was no apparent decrease in the H2 and CO selectivity. Adding O2 did not increase the portion of combustion in the overall reaction. Rather, an excess O2 supply from partial oxidation stoichiometry resulted in an increase in CO2 selectivity without a reduction in CO selectivity. Heavy hydrocarbon species were identified as a source of CO2 in excess O2 conditions due to preferential oxidative cracking. The additional oxidation of C1–C4 species by excess O2 provided a minor contribution to CO2. Excess O2 affects soot generation characteristics by suppressing the agglomeration of soot particles, resulting in smaller particle generation. However, the oxidation of soot particles does not provide a major contribution to increasing the CO2 selectivity. The results show that in a real reforming process, controlling the O2 supply does not have a strong effect on the process selectivity of hydrogen.

• Effects of adsorption and temperature on a nonthermal plasma process for removing VOCs

  Authors: Young-Hoon Song, Seock-Joon Kim, Kyung-Il Choi, Toshiaki Yamamoto

  Journal of Electrostatics.

  Simultaneous use of nonthermal plasma and adsorption process for removing volatile organic compounds (VOCs) has been investigated. Toluene (C7H8) and propane (C3H8), which have different adsorptionSimultaneous use of nonthermal plasma and adsorption process for removing volatile organic compounds (VOCs) has been investigated. Toluene (C7H8) and propane (C3H8), which have different adsorption behavior, were treated using three different types of the barrier discharge reactors packed with glass, macro-porous γ-Al2O3, or molecular sieve 5A pellets mixed with the γ-Al2O3 beads, respectively. Test results show that the removal rates of the VOCs treated by nonthermal plasma process increase with the assistance of adsorption. The enhanced removal rates with the adsorption process are maintained under increased temperature conditions, although the adsorption capability is apparently decreased as the temperature increases. In addition, O3 and HNO3 generated from the nonthermal plasma process are significantly decreased with γ-Al2O3 beads, which is another technical advantage to use γ-Al2O3 beads.

• Production of fusion mussel adhesive fp-353 in Escherichia coli.

  Authors: Youngsoo Gim, Dong Soo Hwang, Seonghye Lim, Young Hoon Song, Hyung Joon Cha

  Biotechnology progress. 24(6):1272-7.

  Mussel adhesive proteins (MAPs) have a potential as environmentally friendly adhesives for use under aqueous conditions. MAPs maybe of particular value in medical applications. We previously reportedMussel adhesive proteins (MAPs) have a potential as environmentally friendly adhesives for use under aqueous conditions. MAPs maybe of particular value in medical applications. We previously reported the functional expression of recombinant foot protein type 5 (fp-5) and foot protein type 3A (fp-3A), both of which have significant adhesion abilities, in Escherichia coli. However, these proteins were produced at low levels because of post-induction cell growth inhibition, and the proteins showed poor post-purification solubility. Here, we design and produce a new type of recombinant MAP, fp-353, that is a fusion protein with fp-3A at each terminus of fp-5. Because fp-353 formed inclusion bodies, host cell growth inhibition did not occur. In addition, the solubility of MAP fp-353 after purification was significantly enhanced, permitting the preparation of a viscous concentrated glue solution for large-scale adhesion strength measurements. Together with large-scale cowhide adhesion measurements and cell-adhesion analyses, we successfully demonstrated that fusion mussel protein fp-353 has potential as a practical alternative bioadhesive.