• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.178-180
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• 2003

We performed semiempirical (AMl and ZINDO) and ab initio (HF and DFT) calculations, to investigate molecular structures and optical properties of DCM and its derivatives. DCM and its derivatives are used as a red fluorescent dopant of the organic electroluminescent host materials, $Alq_3$. We have studied the relationship between the molecular structure and the optical properties of these molecules for the improvement of EL efficiencies. Wavelength at the absorption maximum was found to be red-shifted when the molecule is substituted with both strong electron donating and withdrawing functional groups. A new red fluorescent dye was predicted by QSPR study based on calculations and experimental data.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.154-154
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• 2010

We have developed transparent OLED with green phosphorescent doped layer using transparent metal cathode deposited by thermal evaporation technique. Phosphorescent guest molecule, $Ir(ppy)_3$, was doped in host mCP for the green phosphorescent emission. Ca/Ag double layers were used as a cathode material of transparent OLED. The turn-on voltage of OLED was 5.2 V. The highest efficiency of the device reachs to 31 cd/A at 2 mA/$cm^2$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.9
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• pp.682-685
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• 2013

We have fabricated blue phosphorescent organic light-emitting devices (OLEDs) on a plastic substrate. The solution coated poly (9-vinylcarbazole) (PVK) host doped with Bis (3,5-difluoro-2-(2-pyridyl)phenyl_(2-carboxypyridyl)irdium(III) (FIrPic) guest molecules was used as an hole transporting emission layer. The device structure was ITO/PVK:FIrpic (50 nm, xwt%)/TAZ 50 nm)/LiF (0.5 nm)/Al (100 nm). The concentration of FIrpic molecule was varied from 1 wt% to 10 wt%. The OLED on plastic substrate exhibited maximum current efficiency of 18 cd/A with 5 wt% FIrpic molecules were doped into the PVK layer.

• Macromolecular Research
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• v.15 no.2
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• pp.129-133
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• 2007

Significant progress has been realized in the design and synthesis of light emitting polymers that emit over the entire visible spectrum. However, up to seventy-five percent of charge recombination events can lead to triplet states that decay non-radiatively. Following the pioneering work in the field of small molecule organic light emitting devices, it has been found that solution processible iridium polymer complexes can be used to harness the wasted triplet energy. In this paper, new results with respect to the electrophosphorescence of solution processible tethered iridium polymer derivatives are presented. Furthermore, our approaches to the design of new high triplet energy conjugated polymer hosts are also reported.

• Journal of Microbiology
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• v.33 no.4
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• pp.283-288
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• 1995

We have identified hemolysin rendering virulency of Vibrio anguilarum grown at 23.deg.C which was evaluated on human RBCs. Hemolysin itself was separated as a single band on non-denaturing gel electrophoresis. Vibrio hemolysin was destroyed by trypsin and proteinase K and was heat labile. Optimal pH for activity was around pH 6 while pI of the molecule was recognized as 5.7, with relative distance (R$\sub$f/) on non-denaturing gel was 0.7. Addition of EDTA and FeCI$\sub$3/ drew the possibility that the production of hemolysin was mainly induced to overcome iron deficiency inside host animalsd infection.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.149.2-149.2
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• 2003

Nitric oxide (NO) is known to work as an important signaling molecule involved in regulating a wide range of biological activities in the neuronal, vascular, and immune system. NO and its metabolites mediate a number of host defence functions and are also implicated in the pathogenesis of tissue damage associated with inflammation. Cyclohexylimminobenzoxathiol LYR-64 compound inhibited LPS-induced NO production in murine macrophages Raw264.7 with an IC50 value of 0.7 uM with 95.9% inhibition at 3 uM, 63.5% at 1 uM and 30.2% at 1 uM. (omitted)

• Journal of Life Science
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• v.20 no.9
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• pp.1420-1425
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• 2010

Innate immunity is the first line of host defense consisting of various molecules against infectious challenges. Mannose-binding lectin (MBL) belongs to the collectin protein family which takes part of innate immunity and is able to recognize specific carbohydrates on the surface of a variety of infectious agents acting as a pattern recognition molecule. In this way, MBL differentiates self from non-self and interacts with other molecules of the immune system. MBL genotype shows various MBL2 polymorphisms which are responsible for MBL deficiency in a substantial portion of the entire human population and for susceptibility to infectious disease. Therefore, it has been highlighted in the relationship between genetic variants and clinical significance. Here we focus on presenting anoverview of our understanding of MBL structure and functions.

• Parasites, Hosts and Diseases
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• v.54 no.1
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• pp.31-38
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• 2016

Specific gene expressions of host cells by spontaneous STAT6 phosphorylation are major strategy for the survival of intracellular Toxoplasma gondii against parasiticidal events through STAT1 phosphorylation by infection provoked $IFN-{\gamma}$. We determined the effects of small molecules of tyrosine kinase inhibitors (TKIs) on the growth of T. gondii and on the relationship with STAT1 and STAT6 phosphorylation in ARPE-19 cells. We counted the number of T. gondii RH tachyzoites per parasitophorous vacuolar membrane (PVM) after treatment with TKIs at 12-hr intervals for 72 hr. The change of STAT6 phosphorylation was assessed via western blot and immunofluorescence assay. Among the tested TKIs, Afatinib (pan ErbB/EGFR inhibitor, $5{\mu}M$) inhibited 98.0% of the growth of T. gondii, which was comparable to pyrimethamine ($5{\mu}M$) at 96.9% and followed by Erlotinib (ErbB1/EGFR inhibitor, $20{\mu}M$) at 33.8% and Sunitinib (PDGFR or c-Kit inhibitor, $10{\mu}M$) at 21.3%. In the early stage of the infection (2, 4, and 8 hr after T. gondii challenge), Afatinib inhibited the phosphorylation of STAT6 in western blot and immunofluorescence assay. Both JAK1 and JAK3, the upper hierarchical kinases of cytokine signaling, were strongly phosphorylated at 2 hr and then disappeared entirely after 4 hr. Some TKIs, especially the EGFR inhibitors, might play an important role in the inhibition of intracellular replication of T. gondii through the inhibition of the direct phosphorylation of STAT6 by T. gondii.

• Parasites, Hosts and Diseases
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• v.60 no.4
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• pp.255-259
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• 2022

Heliminthic paramyosin is a multifunctional protein that not only acts as a structural protein in muscle layers but as an immune-modulatory molecule interacting with the host immune system. Previously, we found that paramyosin from Clonorchis sinensis (CsPmy) is bound to human complement C9 protein (C9). To analyze the C9 binding region on CsPmy, overlapping recombinant fragments of CsPmy were produced and their binding activity to human C9 was investigated. The fragmental expression of CsPmy and C9 binding assays revealed that the C9 binding region was located at the C-terminus of CsPmy. Further analysis of the C-terminus of CsPmy to narrow the C9 binding region on CsPmy indicated that the region flanking ⁷³¹Leu-⁷⁸⁰Leu was a potent C9 binding region. The CsPmy fragments corresponding to the region effectively inhibited human C9 polymerization. These results provide a precise molecular basis for CsPmy as a potent immunomodulator to evade host immune defenses by inhibiting complement attack.

• Bulletin of the Korean Chemical Society
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• v.26 no.5
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• pp.769-775
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• 2005

An efficiency of Monte Carlo (MC) docking simulations was examined for the prediction of chiral discrimination by cyclodextrins. Docking simulations were performed with various computational parameters for the chiral discrimination of a series of 17 enantiomers by $\beta$-cyclodextrin ($\beta$-CD) or by 6-amino-6-deoxy-$\beta$-cyclodextrin (am-$\beta$-CD). A total of 30 sets of enantiomeric complexes were tested to find the optimal simulation parameters for accurate predictions. Rigid-body MC docking simulations gave more accurate predictions than flexible docking simulations. The accuracy was also affected by both the simulation temperature and the kind of force field. The prediction rate of chiral preference was improved by as much as 76.7% when rigid-body MC docking simulations were performed at low-temperatures (100 K) with a sugar22 parameter set in the CHARMM force field. Our approach for MC docking simulations suggested that the conformational rigidity of both the host and guest molecule, due to either the low-temperature or rigid-body docking condition, contributed greatly to the prediction of chiral discrimination.