• Progress in Superconductivity
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• v.14 no.2
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• pp.99-101
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• 2012

Fluorescent yield X-ray absorption fine structure (XAFS) spectroscopy is useful for analyzing local structure of specific elements in matrices. We developed an XAFS apparatus with a 100-pixel superconducting tunnel junction (STJ) detector array with a high sensitivity and a high resolution for light-element dopants in wide-gap semiconductors. An STJ detector has a pixel size of $100{\mu}m$ square, and an asymmetric layer structure of Nb(300 nm)-Al(70 nm)/AlOx/Al(70 nm)-Nb(50 nm). The 100-pixel STJ array has an effective area of $1mm^2$. The XAFS apparatus with the STJ array detector was installed in BL-11A of High Energy Accelerator Research Organization, Photon Factory (KEK PF). Fluorescent X-ray spectrum for boron nitride showed that the average energy resolution of the 100-pixels is 12 eV in full width half maximum for the N-K line, and The C-K and N-K lines are separated without peak tail overlap. We analyzed the N dopant atoms implanted into 4H-SiC substrates at a dose of 300 ppm in a 200 nm-thick surface layer. From a comparison between measured X-ray Absorption Near Edge Structure (XANES) spectra and ab initio FEFF calculations, it has been revealed that the N atoms substitute for the C site of the SiC lattice.

• Biomedical Science Letters
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• v.24 no.2
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• pp.134-137
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• 2018

S100A8 and S100A9 are involved in pathogenesis of cancer by induction or inhibition of cancer as well as inflammation. In this study, we investigated the association of S100A8 and S100A9 with pathogenesis of leukemia using human monocytic leukemia cells, THP-1. The expression of TLR4, which is a known receptor of S100A8 and S100A9, was examined by using flow cytometry and Western blotting. THP-1 cells have high surface and cytosol expression of TLR4. S100A8 and S100A9 suppressed the cell survival, and this suppression was found to be associated with apoptosis because they increased the number of apoptotic cells in a dose- and a time-dependent manners. However, S100A8 and S100A9 had no effect on the survival and apoptosis of monocytes isolated from the peripheral blood. We next examined the apoptotic effect of lipopolysaccharide (LPS) and monophosphoryl lipid A (MPLA), which are other ligands of TLR4, in THP-1 cells. Lipopolysaccharide had no effect on cell survival, but MPLA is effective on the cell apoptosis. These results suggest that S100A8 and S100A9 may regulate leukemia cell survival via TLR4, which is an essential receptor in the pro-apoptotic mechanism induced by S100A8 and S100A9. These findings may shed light on development of a possible therapeutic drug for leukemia treatment.

• Korean Journal of Veterinary Research
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• v.36 no.2
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• pp.359-369
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• 1996

An effective candidate subunit vaccine was prepared by using the immunostimulating complexs(ISCOMs) with Quil A and recombinant protein(gp50, gIII and inactive $\alpha$-ADV) Aujeszky's disease virus(ADV). The weaned pigs were twice immunized with a ADV-ISCOMs, and followed by intramuscular challenge with $1{\times}10^4$ $TCID_{50}$ ADV(strain Yangsan). The unvaccinated pigs were also challenged with same dose of ADV. At 5 days after challenge, the control pigs have developed ADV clinical signs. Whereas, the vaccinated pigs protected them from ADV-induced acute symptoms and death. Also, to identify the lymphocyte subpopulation in peripheral blood with pigs from ADV-ISCOMs vaccinated and control group, lymphocyte reacted with a panel of monoclonal antibodies which are specific to swine leukocyte surface antigens and assayed by the flow cytometry. MHC class I, CD2, CD8, N cells, CD11a, and CD45 antigen positive cells were decreased after inoculating virulent ADV Yangsan strain in control group. The data indicated that ISCOMs technique was useful in ADV subunit vaccine preparation and demonstrated the importance of gp50, gIII as a component of ADV vaccine.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.5
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• pp.17-23
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• 2013

Six-valent chromium ($Cr^{6+}$) is a highly toxic pollutant, supplied in a variety of industrial activities such as leather tanning, cooling tower blowdown, and plating. Herein, we investigated the removal of $Cr^{6+}$ from aqueous phase using low-cost adsorbents. Steel slag, montmorillonite, illite, kaolinite, red mud, and acid treated red mud with 0.5, 1.0, and 2.0 M HCl were used as adsorbent for the removal of $Cr^{6+}$ and the results showed that acid treated red mud with 2.0 M HCl (ATRM-2.0 M) had higher adsorption capacity of $Cr^{6+}$ than other adsorbents used. Accordingly, $Cr^{6+}$ removal by ATRM-2.0 M were studied in a batch system with respect to changes in initial concentration of $Cr^{6+}$, initial solution pH, adsorbent dose, adsorbent mixture, and seawater. Equilibrium sorption data were described well by Freundlich isotherm model. The influence of initial solution pH on $Cr^{6+}$ adsorption was insignificant. The use of the ATRM-2.0 M alone was more effective than mixing it with other adsorbents including red mud, zeolite, oyster shell, lime stone, and montmorillonite for the removal of $Cr^{6+}$. The $Cr^{6+}$ removal of the ATRM-2.0 M was slightly less in seawater than deionized water, resulting from the presence of anions in seawater competing for the favorable adsorption site on the surface of ATRM-2.0 M. It was concluded that the ATRM-2.0 M can be used as a potential adsorbent for the removal of $Cr^{6+}$ from the aqueous solutions.

• Korean Journal of Veterinary Research
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• v.42 no.2
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• pp.153-162
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• 2002

For the induction of arthropathy, 5% hydrogen peroxide($H_2O_2$) was injected for 5 weeks into the intraarticular space of the New Zealand white rabbits to damage articular cartilage. Alginic acid of low molecular weight (2%) made from macromolecular alginate treated with enzyme was administered into articular space at the dose of 5 mg/kg twice a week for 3 and 6 weeks using 1 ml syringe and 26 G needle. Saline was injected for the control. Tissues surrounding the articulation were obtained for the measurements of superoxide dismutase(SOD) activity as a major antioxidant enzyme and malondialdehyde (MDA) as a lipid peroxidation level. Histopathologic examination on the surface of articular cartilage was carried out. Data showed that injection of hydrogen peroxide for 5 weeks had led to the induction of free radical damage and of articular cartilage change as confirmed by microscopic observation. The application of hydrogen peroxide caused a gradual increase in the SODs and MDA. These patterns were similar after 3 and 6 weeks of alginate treatment. Furthermore, microscopic examinations revealed that hydrogen peroxide caused flaking, fibrillation, fissuring, denudation, and hypocellularity in the articular surfaces. In conclusion, lipid peroxidation was demonstrated in the articular cartilage by the administration of hydrogen peroxide in the rabbit model. This lipid peroxidation could be caused by oxygen free radicals. The histologic and enzymatic correlations on lipid peroxidation in the articulation have provided a better understanding of arthropathy. It is possible to take advantage of these findings to evaluate effective alginate dosage more efficiently.

• BMB Reports
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• v.39 no.6
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• pp.722-729
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• 2006

Recently, we have reported that 3-hydrogenkwadaphnin (3-HK), a diterpene ester isolated from Dendrostellera lessertii (Thymealeaceae), is very effective against leukemia cell lines without any detectable effects on normal cells (Moosavi et al., 2005b). In this study, we report that 3-HK induces $G_1$ cell-cycle arrest, differentiation and apoptosis in APL NB4 cell line. Indeed, the drug between 24 to 96 h induced 7-65% growth inhibition of NB4 cells. Cell viability was also decreased by 2-55% between 24 to 96 h treatments with the drug, respectively. These effects of the drug were also dose-dependent. According to flow cytomtry results, 3-HK (15 nM) induced a significant G1-arrest up to 24 h which was consequently followed with appearance of sub-$G_1$ peak at 72 to 96 h. Hoechst 33258 staining and DNA fragmentation assays confirmed the occurrence of apoptosis among the treated cells. On the other hand, NBT reducing assay, Wright-Giemsa staining, phagocytic activity and expression of cell surface markers (CD11b and CD14) confirmed that the inhibition of proliferation is associated with differentiation especially toward macrophage-like morphology. Interestingly, 3-HK at 5 and 10 nM enhanced the effects of all-trans retinoic acid (ATRA) in NB4 cells. Based on these results, 3-HK might become an ideal candidate for treatment of APL patients pending full exploration of its biological functions.

• Journal of Radiation Protection and Research
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• v.42 no.4
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• pp.177-188
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• 2017

Background: Radiation-induced pneumonitis and pulmonary fibrosis are common dose-limiting complications in patients receiving radiotherapy for lung, breast, and lymphoid cancers. In this study, we investigated the characteristics of effective immune cells related to pneumonitis and fibrosis after irradiation. Materials and Methods: After anesthesia, the whole thorax of C57BL/6 mice was irradiated at 14 Gy. The lung tissue and bronchoalveolar lavage fluid were collected at defined time points post-irradiation for the determination of histological and immunohistochemical analysis and inflammatory cell population infiltrated into the lung. Results and Discussion: Whole thoracic irradiation increased the deposition of extracellular matrix (ECM), lung weight, and pleural effusions, which started to die from 4 months later. At 4 months after irradiation, the numbers of macrophages and lymphocytes as well as neutrophils were increased dramatically in the lung. Interestingly, the macrophages that were recruited into the lung after irradiation had an enlarged foamy morphology. In addition, the expressions of chemokines (CCL-2, CCL-3, CXCL-10) for the attraction of macrophages and T cells were higher in the lung of irradiated mice. The high expressions of these chemokines were sustained up to 6 months following irradiation. In thoracic irradiated mice, infiltrated macrophages into the lung had the high levels of Mac-3 antigens on their surface and upregulated the hallmarks of alternatively activated macrophages such as arginase-1 and CD206. Furthermore, the levels of IL-4 and IL-13 were higher in a BAL fluid of irradiated mice. Conclusion: All results show that thoracic irradiation induces to infiltrate various inflammation-related immune cells, especially alternatively activated macrophages, through enhancing the expression of chemokines, suggesting that alternatively activated macrophages are most likely important for leading to pulmonary fibrosis.

• Journal of Microbiology
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• v.40 no.2
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• pp.119-124
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• 2002

Experiments for the characterization of inactivation were performed in a series of batch processes with the total coliform used as a general indicator organism based on the chlorine residuals as a disinfectant. The water samples were taken from the outlet of a settling basin in a conventional surface water treat- ment system that is provided with the raw water drawn from the mid-stream of the Han River, The inactivation of total coliform was experimentally analysed for the dose of disinfectants contact time, filtration and mixing intensity. The curves obtained from a series of batch processes were shaped with a general tailing-off and biphasic mode of inactivation, i.e. a sharp loss of bacterial viability within 15 min followed by an extended phase. In order to observe the effect of carry-over suspended solids on chlorine consumption and disinfection efficiency, the water samples were filtered, prior to inoculation with coliforms, with membranes of both 2.5$\mu$m and 11.0 $\mu$m pore size, and with a sand tilter of 1.0 mm in effective size and of 1.4 in uniformity coefficient. As far as the disinfection efficiency is concerned, there were no significant differences. The parameters estimated by the models of Chick-Wat-son, Hom and Selleck from our experimental data obtained within 120 min are: log(N/N$\_$0/)=-0.16CT with n=1, leg(N/N$\_$0/)=-0.71C$\^$0.87/ with n 1 for the Chick-Watson model, log (N/N$\_$0/)=-1.87C$\^$0.47/ T$\^$0.36/ for the Hom model, log (MHo)=-2.13log (1+CT/0.11) for the Selleck model. It is notable that among the models reviewed with regard to the experimental data obtained, the Selleck model appeared to most closely resemble the total coliform survival curve.

• Parasites, Hosts and Diseases
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• v.58 no.2
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• pp.173-179
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• 2020

Leishmaniasis is a prevalent cause of death and animal morbidity in underdeveloped countries of endemic area. However, there is few vaccine and effective drugs. Antimicrobial peptides are involved in the innate immune response in many organisms and are being developed as novel drugs against parasitic infections. In the present study, we synthesized a 5-amino acid peptide REDLK, which mutated the C-terminus of Pseudomonas exotoxin, to identify its effect on the Leishmania tarentolae. Promastigotes were incubated with different concentration of REDLK peptide, and the viability of parasite was assessed using MTT and Trypan blue dye. Morphologic damage of Leishmania was analyzed by light and electron microscopy. Cellular apoptosis was observed using the annexin V-FITC/PI apoptosis detection kit, mitochondrial membrane potential assay kit and flow cytometry. Our results showed that Leishmania tarentolae was susceptible to REDLK in a dose-dependent manner, disrupt the surface membrane integrity and caused parasite apoptosis. In our study, we demonstrated the leishmanicidal activity of an antimicrobial peptide REDLK from Pseudomonas aeruginosa against Leishmania tarentolae in vitro and present a foundation for further research of anti-leishmanial drugs.

• Applied Chemistry for Engineering
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• v.27 no.2
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• pp.199-204
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• 2016

The adsorption of Rhodamine-B dye using granular activated carbon from aqueous solution was investigated. Adsorption experiments were carried out as a function of the adsorbent dose, pH initial concentration, contact time and temperature. The equilibrium adsorption data showed a good fit to Langmuir isotherm model. Based on the estimated Langmuir separation factor ($R_L$ = 0.0164~0.0314), our adsorption process could be employed as an effective treatment method. The kinetics of adsorption followed the pseudo first order model. Also, the negative values of Gibbs free energy (-4.51~-13.44 kJ/mol) and positive enthalpy (128.97 kJ/mol) indicated that the adsorption was spontaneous and endothermic process. The isosteric heat of adsorption increased with increase in the surface loading indicating lateral interactions between the adsorbed dye molecules.