• Journal of Microbiology and Biotechnology
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• v.9 no.6
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• pp.826-831
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• 1999

${\beta}-Glucan$, one of the major cell wall components of Saccharomyces cerevisiae, is known to enhance the immune function, especially by activating macrophages. Accordingly, in an effort to develop a safe and efficient immune stimulatory agent, we prepared crude ${\beta}-glucan$ (glucan-p1) and partially purified ${\beta}-glucan$ that was free of mannoproteins (glucan-p2), and evaluated their effect on both the macrophage function and resistance to E. coli-induced peritonitis. To investigate the function of the macrophages, phagocytosis, $TNF-{\alpha}$ secretion, oxygen burst, and the expression of cytokine genes such as $IFN-{\gamma}$ and IL-12 were analyzed. Glucan-p2 markedly stimulated the macrophages with all these parameters. Glucan-p1, however, did not stimulate phagocytosis, yet it induced $TNF-{\alpha}$ secretion, oxygen burst, and the expression of $IFN-{\gamma}$ and IL-12, although less efficiently than glucan-p2. Finally, to test the in vivo protective effect of {\beta}-glucan against infection, the survival of mice from E. coli-induced peritonitis was investigated. After 24 h of the peritoneal challenge of E. coli, all of the mice treated with glucan-p2 survived whereas none survived in the control group. Glucan-p1 showed only a marginal effect in protecting the mice. These results suggest that mannoprotein-free gluean-p2, but not gluean-p1, can serve as an effective immune-stimulating agent.

• Journal of Microbiology
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• v.41 no.3
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• pp.266-270
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• 2003

Orientia tsutsugamushi, an obligate intracellular bacterium, is the causative agent of scrub typhus which is histopathologically characterized by inflammatory manifestations. To understand the pathogenesis of scrub typhus, chemokine gene expression in mice after infection with O. tsutsugamushi was investigated. The mRNAs that were upregulated included macrophage inflammatory proteins 1${\alpha}$/${\beta}$ (MIP-1${\alpha}$/${\beta}$), MIP-2, monocyte chemoattractant protein 1, RANTES (regulated upon activation, normal T-cell expressed and secreted), and gamma-interferon-inducible protein 10. Peak expression of these chemokines was observed six days after infection. These responses returned to or approached baseline preinfection levels by eight days after infection. Chemokine profiles in infected mice were well correlated with the kinetics of inflammatory cell infiltration. Thus, O. tsutsugamushi appears to be a strong inducer of chemokines which may significantly contribute to the inflammation observed in scrub typhus by attracting and activating phagocytic leukocytes.

• Carbon letters
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• v.4 no.3
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• pp.126-132
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• 2003

Granular Activated Carbon (GAC) has been proven to be an excellent material for many industrial applications. A systematic study has been carried out of the kinetics of physical as well as chemical activation of phenolic resin chars. Physical activation was carried out using $CO_2$ and chemical activation using KOH as activating agent. There are number of factors which influence the rate of activation. The activation temperature and residence time at HTT varied in the range $550{\sim}1000^{\circ}C$ and $\frac{1}{2}{\sim}8$ hrs respectively. Kinetic studies show that the rate of chemical activation is 10 times faster than physical activation even at much lower temperature. Above study show that the chemical activation process is suitable to prepare granular activated carbon with very high surface area i.e.$ 2895\;m^2/g$ in short duration of time i.e. 1 to 2 hrs at lower temperature i.e. $750^{\circ}C$ from phenolic resins.

• Carbon letters
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• v.1 no.3_4
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• pp.154-157
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• 2001

Composite adsorbents were prepared by mixing water plant sludge with phenolic resin having the ratio of 1 : 1, 1 : 2, and 1 : 3 respectively, curing from $100^{\circ}C$ to $170^{\circ}C$ under $N_2$ atmosphere, and then activating with $N_2$ at $700^{\circ}C$. Thermal property, specific surface area and morphology of the composite adsorbents as well as their precursors were measured by TGA, BET and SEM respectively. Removal efficiency of the composite adsorbents to ${NH_4}^+$ and TOC was compared with those of commercial zeolite and activated carbon. The adsorbents presented very promising TOC removal efficiency of 98%, which was identical level to that of commercial activated carbon while they displayed removal efficiency, only 32%, of ${NH_4}^+$. Therefore, this composite adsorbent considered as the alternative material of commercial activated carbon, used as an expensive removal agent of organic substances and THM in water treatment plant and it also suggested a possibility of practical application in other processes.

• Carbon letters
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• v.2 no.2
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• pp.105-108
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• 2001

In this work, the activated carbons (ACs) with high micropores were synthesized from the polystyrene (PS) with KOH as activating agent. And the influence of activation temperature on porosity of the ACs studied was investigated. The porous structures of ACs were characterized by nitrogen adsorption at 77K using BET and D-R equations, and MP and BJH methods. The weight loss behaviors of the samples impregnated with KOH were also monitored using thermogravimetric analyzer (TGA). As a result, it was found that the samples could be successfully converted into ACs with well-developed micropores. From the results of pore size analysis, it was confirmed that elevated activation temperature does lead to the formation and deepening of microstructures without significant change in mesostructures. A thermogravimetric study showed that KOH could suppress the thermal decomposition of the sample, resulting in the increase of carbon yields.

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.144-149
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• 1993

We have identified a T cell-activating material in the culture supernatant of Streptomyces species. The factor in microbial culture supernatant (MCS) induced thymocyte proliferation in a does dependent fashion and it could be detected by immunoblot analysis using anti-interleukin-1(IL-1) antibody. The factor in MCS was slightly larger(about 21 kd) in its molecular weight than IL-1 on SDS-PAGE. When 125I-MCS was covalently coupled with homo-bifunctional cross-linking agent, disuccinimidyl-propionate to IL-1 receptor(IL-1R) on mouse thymoma cell(EL-4) and immunoprecipitated with anti-IL-1R antibody the molecular weight of this complex of 110 kd was observed.

• Carbon letters
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• v.8 no.2
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• pp.134-136
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• 2007

In this work, activated carbons (ACs) were prepared from polystyrene-based cation-exchangeable resin (PSI) by a chemical activation with KOH as an activating agent. The surface morphologies were observed by using SEM, and the textural properties were investigated by using nitrogen adsorption at 77 K. From the experimental results, it was found that the well-developed micro- and mesopores were produced by a chemical activation, and the textural properties including specific surface areas and pore volumes were greatly enhanced. The electrochemical behaviors of the ACs showed similar phenomena with that of textural properties. These results indicated that KOH activation played an important role in the changes of surface, and pore structures, resulting in enhancing the electrochemical properties of the ACs prepared in present work.

• Korean Journal of Plant Resources
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• v.34 no.6
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• pp.536-541
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• 2021

In this study, we investigated whether Hibiscus manihot flowers (HMF) exhibits immunostimulatory activity in RAW264.7 cells. HMF increased the production of immunostimulatory factors such as NO, iNOS, IL-1β and TNF-α in RAW264.7 cells. TLR2 and TLR4 blocked HMF-mediated production of immunostimulatory factors in RAW264.7 cells. In addition, the inhibition of MAPK signaling pathway reduced HMF-mediated production of immunostimulatory factors. From these results, HMF is thought to promote the production of immunostimulatory factors through activating TLR2/4/MAPK signaling in macrophages. It is believed that HMF can be developed as an agent related to immune enhancement in the future.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.87-87
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• 2020

In this study, we investigated the immune-enhancing activity of water extracts from Hydrangea macrophylla subsp. serrata (WE-HML). WE-HML increased cell viability and production of immunomodulators, which contributed to activating phagocytic activity in RAW264.7 cells. Inhibition of JNK and NF-κB reduced the production of immunomodulators by WE-HML. ROS inhibition suppressed the production of immunomodulators, and the activation of JNK and NF-κB signaling by WE-HML. TLR4 inhibition attenuated the production of immunomodulators, and activation of JNK and NF-κB signaling by WE-HML. In the immunosuppressed mouse model, WE-HML increased the spleen index, the levels of the cytokines, the numbers of white blood cells, lymphocytes, and neutrophils. However, WE-HML inhibited LPS-mediated overproduction of pro-inflammatory mediators in RAW264.7 cells, which indicated that WE-HML may have anti-inflammatory activity under excessive inflammatory conditions. Taken together, WE-HML may be considered to have immune-enhancing activity and expected to be used as a potential immune-enhancing agent.

• Restorative Dentistry and Endodontics
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• v.45 no.4
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• pp.45.1-45.8
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• 2020

Objective: The aim of this study was to introduce a gelatin/bovine serum albumin (BSA) tissue standard, which provides dissolution properties identical to those of biological tissues. Further, the study evaluated whether the utilization of endodontic activating devices led to enhanced phantom dissolution rates. Materials and Methods: Bovine pulp tissue was obtained to determine a benchmark of tissue dissolution. The surface area and mass of samples were held constant while the ratio of gelatin and BSA were varied, ranging from 7.5% to 10% gelatin and 5% BSA. Each sample was placed in an individual test tube that was filled with an appropriate sodium hypochlorite solution for 1, 3, and 5 minutes, and then removed from the solution, blotted dry, and weighed again. The remaining tissue was calculated as the percent of initial tissue to determine the tissue dissolution rate. A radiopaque agent (sodium diatrizoate) and a fluorescent dye (methylene blue) were added to the phantom to allow easy quantification of phantom dissolution in a canal block model when activated using ultrasonic (EndoUltra) or sonic (EndoActivator) energy. Results: The 9% gelatin + 5% BSA phantom showed statistically equivalent dissolution to bovine pulp tissue at all time intervals. Furthermore, the EndoUltra yielded significantly more phantom dissolution in the canal block than the EndoActivator or syringe irrigation. Conclusions: Our phantom is comparable to biological tissue in terms of tissue dissolution and could be utilized for in vitro tests due to its injectability and detectability.