• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.1034-1040
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• 2022

Fas-associated death domain (FADD) is an adapter molecule that bridges the interaction between receptor-interacting protein 1 (RIP1) and aspartate-specific cysteine protease-8 (caspase-8). As the primary mediator of apoptotic cell death, caspase-8 has two N-terminal death-effector domains (DEDs) and it interacts with other proteins in the DED subfamily through several conserved residues. In the tumor necrosis receptor-1 (TNFR-1)-dependent signaling pathway, apoptosis is triggered by the caspase-8/FADD complex by stimulating receptor internalization. However, the molecular mechanism of complex formation by the DED proteins remains poorly understood. Here, we found that direct DED-DED interaction between FADD and caspase-8 and the structure-based mutations (Y8D/I128A, E12A/I128A, E12R/I128A, K39A/I128A, K39D/I128A, F122A/I128A, and L123A/I128A) of caspase-8 disrupted formation of the stable DED complex with FADD. Moreover, the monomeric crystal structure of the caspase-8 DEDs (F122A/I128A) was solved at 1.7 Å. This study will provide new insight into the interaction mechanism and structural characteristics between FADD and caspase-8 DED subfamily proteins.

• Polymer(Korea)
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• v.26 no.2
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• pp.218-226
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• 2002

For the preparation of high resilience polyurethane (PU) foams with polyether type cell openers which have different ethylene oxide (EO) content, molecular weight and chain structure, the influences of tell opener structure on the kinetics, rheology, structural stability, open cell content and mechanical properties of the obtained foam were investigated. It was observed that urea formation reaction was delayed with the increase of EO content and incorporation of ester linkage in cell opener molecule and was relatively independent on the molecular weight. With the rheological studies, the decreases of viscosity and storage modulus were confirmed for the increase of EO content and molecular weight, so that the resulted foam had low structural stability and high open cell content. The cell opener having ester linkage in molecule exhibited the lowest values of viscosity and storage modulus and the obtained foam has high open cell content. However, the structural stability increased due to the larger intermolecular interaction of ester linkage. The hardness, tensile strength, tear strength and elongation of foam were deteriorated with increase of EO content and molecular weight of tell opener. On the other hand, the cell opener having ester linkage in molecule improved the values of tensile strength, tear strength and elongation.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.72-81
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• 2007

Quantitative structure-activity relationships (QSARs) on the pre-emergency herbicidal activity and reactivity of a series of new O,O-dialkyl-1-phenoxyacetoxy-1-methylphosphonates (S) analogues against seed of cucumber (Cucumus Sativa) were discussed quantitatively using 2D-QSAR and HQSAR methods. The statistical values of HQSAR model were better than that of 2D-QSAR model. From the frontier molecular orbital (FMO) interaction between substrate molecule (S) and $BH^+$ ion (I) in PDH enzyme, the electrophilic reaction was superior in reactivity. From the effect of substituents, $R_2$-groups in substrate molecule (S) contributed to electrophilic reaction with carbonyl oxygen atom while X, Y-groups contributed to nucleophilic reaction with carbonyl carbon atom. And the influence of X,Y-groups was more effective than that of $R_2$-groups. As a results of 2D-QSAR model (I & II) and atomic contribution maps with HQSAR model, the more length of X, Y-groups is longer, the more herbicidal activity tends to increased. And also, the optimal ${\epsilon}LUMO$ energy, $({\epsilon}LUMO)_{opt.}$=-0.479 (e.v.) of substrate molecule is important factor in determining the herbicidal activity. It is predicted that the herbicidal activity proceeds through a nucleophilic reaction. From the analytical results of 2D-QSAR and HQSAR model, it is suggested that the structural distinctions and descriptors that contribute to herbicidal activities will be able to applied new herbicide design.

• Journal of Korean Neurosurgical Society
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• v.29 no.4
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• pp.477-484
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• 2000

Objective : Despite advances in the understanding of tumor biology and the tumor immunology, there has been no effective treatment. The Intercellular adhesion molecule-1(ICAM-1) has been shown to be important in interaction involving cells of the immune system and to be upregulated in a number of cell culture systems by cytokines, including immune interferon($IFN-{\gamma}$) and tumor necrosis $factor-{\alpha}$($TNF-{\alpha}$). ICAM-1 has been identified as one of the ligands for lymphocyte function-associated antigen-1(LFA-1). The effectiveness of various cytokines to ICAM-1 induction on cultured human glioblastoma cell lines and potential efficacy of immunotherapy were studied. Method : Human glioblastoma cell lines, U-251 MG, U-373 MG were trypsinized and suspended at $1{\times}10^5cells/ml$ and grown on 8 well chamber slide, the cells were incubated in 0.3ml medium alone or medium containing $IFN-{\gamma}$(1000U/ml) or $TNF-{\alpha}$(250U/ml) or $IFN-{\gamma}$ plus $TNF-{\alpha}$ for 6, 12, 24, 48 and 72 hours. The coverslip were then removed and stained with a 1/30 dilution of anti-ICAM-1 antibody. Result : Surface antigen expression of ICAM-1 was increased by incubating glioblastoma cell lines with $IFN-{\gamma}$ and $TNF-{\alpha}$. Combined effect of $IFN-{\gamma}$ and $TNF-{\alpha}$ has induced more ICAM-1 expression on glioblastoma cell lines. Upregulation of ICAM-1 expression in an established glioblastoma cell line was of greater magnitude and more rapid following incubation with $IFN-{\gamma}$ plus $TNF-{\alpha}$. Surface antigen expression of ICAM-1 was increased for up to 48 hours after cytokine treatment on both cell lines(p<0.05). There was no difference on both cell lines(p>0.05). Conclusion : The results of the present study indicate that ICAM-1 expression in glioblastoma cell lines, U-251 MG and U-373 MG, are induced and enhanced after treatment with $IFN-{\gamma}$ and $TNF-{\alpha}$. Combined effect of $IFN-{\alpha}$ and $TNF-{\gamma}$ is stronger and more rapid than $IFN-{\gamma}$ or $TNF-{\alpha}$ alone.

• Bulletin of the Korean Chemical Society
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• v.26 no.11
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• pp.1728-1734
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• 2005

The interactions of Cu(II)-meso-Tetrakis(n-N-methylpyridiniumyl)porphyrin (n = 2,3,4), respectively referred to as o-, m- and p-CuTMPyP, and DNA, poly$[d(A-T)_2]$ and poly$[d(G-C)_2]$ were investigated by circular and linear dichroism (CD and LD). In the o-CuTMPyP case, in which the rotation of the pyridinium ring is prevented, the shape of the CD spectrum when associated to DNA and poly$[d(A-T)_2]$ resembles and is characterized by a positive band at a low drug to DNA concentration ratio (R ratio) and is bisignate at a high R ratio. The former CD spectrum shape has been attributed to porphyrin that is bound monomerically outside of DNA while the latter can be attributed to those that are stacked. When o-CuTMPyP is bound to poly$[d(G-C)_2]$, the excitonic CD appeared at a relatively high R ratio. In contrast, a characteristic negative CD band in the Soret region was apparent for both m- and p-CuTMPyP when bound to DNA and poly$[d(G-C)_2]$ at the low R ratios, indicating that the porphyrin molecule intercalates. However, the DNA is bent near the intercalation site and the plane of the porphyrin molecule tilts relative to the DNA helix axis, as judged by the magnitude of the reduced LD. Various stacking patterns were identified by the shape of the CD spectrum for m- and p-CuTMPyP when bound to poly$[d(A-T)_2]$. Three species for the former complex and two for the latter complex were found which may reflect the extent of the stacking.

• Korean Journal of Microbiology
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• v.50 no.2
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• pp.169-172
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• 2014

Recently, Hepatitis C virus (HCV) replication system has been established using human hepatoma cells (huh cell) and a variety of HCV clones. In this study, we established an infectious HCV replication system using huh7.5 cells and J6/JFH1 clone (genotype 2a). In addition, we investigated the antigen presentation capability of HCV-infected huh7.5 cells to HCV-specific T cells. Interestingly, HCV-infected huh7.5 cells were not capable of activating HCV-specific T cells. However, huh7.5 cells stimulated by exogenous HCV peptide were able to activate HCV-specific T cells, which was shown to produce TNF-${\alpha}$ and IFN-${\gamma}$. We further examined if HCV infection has an inhibitory effect on the expression of MHC class I molecule of huh7.5 cells. We found that HCV infection did not change the expression level of MHC class I molecule on huh7.5 cells.

• IMMUNE NETWORK
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• v.3 no.1
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• pp.8-15
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• 2003

Background: CD30 is a member of TNF receptor family and expressed on lymphocytes and other hematopoietic cells following activation as well as Hodgkin and Reed-Sternberg cells in Hodgkin's lymphoma. In this study, CD30-mediated regulation of cell adhesion molecule expression on normal activated mouse T cells was investigated. Methods: Mouse T cells were activated with anti-CD3 antibody for induction of CD30, which was cross-linked by immobilized anti-CD30 antibody. Results: High level of CD30 expression on T cells was observed on day 5, but only little on day 3 even under culture condition resulting in an identical T cell proliferation, indicating that CD30 expression requires a prolonged stimulation up to 5 days. Cross-linking of CD30 alone altered neither proliferation nor apoptosis of normal activated T cells. Instead, CD30 appeared to promote cell adherence to culture substrate, and considerably upregulated ICAM-1 and, to a lesser extent, ICAM-2 expression on activated T cells, whereas CD2 and CD18 (LFA-1) expression was not affected. None of cytokines known as main regulators of ICAM-1 expression on tissue cells (IL 4, $IFN{\gamma}$ and $IFN{\alpha}$) enhanced ICAM-1 expression in the absence of CD30 signals. On the other hand, addition of $NF-{\kappa}B$ inhibitor, PDTC (0.1 mM) completely abrogated the CD30-mediated upregulation of ICAM-1 expression, but not CD2 and ICAM-2 expression. Conclusion: This results support that CD30 upregulates ICAM-1 expression of T cell and such regulation is not mediated by higher cytokine production but $NF-{\kappa}B$ activation. Therefore, CD30 may play important roles in T-T or T-B cell interaction through regulation of ICAM-1, and -2 expression.

• Nutritional Sciences
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• v.8 no.3
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• pp.153-158
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• 2005

Numerous natural herbal compounds have been reported to inhibit adhesion and migration of leukocytes to the site of inflammation Licorice extracts, which have been widely used in traditional Chinese medicinal preparation, possess various pharmacological effects. Isoliquiritigenin, a biogenetic precursor of flavonoids with various pharmacological effects, is a natural pigment present in licorice. We attempted to explore whether licorice extracts and isoliquiritigenin mitigate monocyte adhesion to tumor necrosis factor-$\alpha$ (TNF-$\alpha$)-activated human umbilical vein endothelial cells (HUVEC). In addition, it was tested whether the inhibition of monocyte adhesion to the activated HUVEC accompanied a reduction in vascular cell adhesion molecule-l expression(VCAM-l). Dry-roasted licorice extracts in methylene chloride but not in ethanol markedly interfered with THP-l monocyte adhesion to INF-$\alpha$-activated endothelial cells. licochalcone A compound isolated from licorice extract in methylene chloride appeared to modestly inhibit the interaction of THP-l monocytes and activated endothelium. In addition, isoliquiritigenin abolished the monocyte adhesion with attenuating VCAM-l protein expression on HUVEC induced by INF-$\alpha$. These results demonstrated that non-polar components from dry-roasted licorice extracts containing licochalcone A as well as isoliquiritigenin were active in blocking monocyte adhesion to cytokine-activated endothelimn, which appeared to be mediated most likely through the inhibition of VCAM-l expression on HUVEC. Therefore, licorice may hamper initial inflammatory events on the vascular endothelium involving induction of endothelial cell adhesion molecules.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3759-3765
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• 2015

Background: Approaches in disruption of MDM2-p53 interactions have now emerged as an important therapeutic strategy in resurrecting wild type p53 functional status. The present study highlights virtual screening strategies in identification of high affinity small molecule non-peptidic inhibitors. Nutlin3A and RG7112 belonging to compound class of Cis-imidazoline, MI219 of Spiro-oxindole class and Benzodiazepine derived TDP 665759 served as query small molecules for similarity search with a threshold of 95%. The query molecules and the similar molecules corresponding to each query were docked at the transactivation binding cleft of MDM2 protein. Aided by MolDock algorithm, high affinity compound against MDM2 was retrieved. Patch Dock supervised Protein-Protein interactions were established between MDM2 and ligand (query and similar) bound and free states of p53. Compounds with PubCid 68870345, 77819398, 71132874, and 11952782 respectively structurally similar to Nutlin3A, RG7112, Mi219 and TDP 665759 demonstrated higher affinity to MDM2 in comparison to their parent compounds. Evident from the protein-protein interaction studies, all the similar compounds except for 77819398 (similar to RG 7112) showed appreciable inhibitory potential. Of particular relevance, compound 68870345 akin to Nutlin 3A had highest inhibitory potential that respectively showed 1.3, 1.2, 1.16 and 1.26 folds higher inhibitory potential than Nutilin 3A, MI 219, RG 7112 and TDP 1665759. Compound 68870345 was further mapped for structure based pharamacophoric features. In the study, we report Cis-imidazoline derivative compound; Pubcid: 68870345 to have highest inhibitory potential in blocking MDM2-p53 interactions hitherto discovered.

• Textile Coloration and Finishing
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• v.12 no.1
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• pp.52-60
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• 2000

In the prior studies, we reported that the dye uptakes of C. I. Disperse Violet 1 on polyester fiber in hexane and cyclohexane were higher than those in the other solvents, as the number of carbon atoms of alkanes decreased, the dye uptake increased, and the logarithmic plot of the dye uptakes vs. the solubilities of the dye showed that the dye uptakes are inversely proportional to the solubilities. In this study, for Interpretation of dyeing behavior of C. I. Disperse Violet 1 on polyester in alkanes, the thremodynamic parameters of dyeing, such as standard affnity, heat of dyeing(enthalpy change), entropy change, diffusion coefficient, and activation energy of diffusion, were obtained from isotherms and dyeing rates at different temperature. As the number of carbon atoms of alkanes increased, the standard affinity decreased, but the heat of dyeing(enthalpy change) and the entropy change showed larger negative values. These results mean that as the number of carbon atoms of alkanes increases, the dye uptake decreases, but both the fraction of the dye molecules dyed at relatively highly aligned or compact region of polyester fiber and the regularity of dye aggregates in the fiber become increased. As the number of carbon atoms of alkanes increased, the diffusion coefficient decreased, but the activation energy of diffusion increased. In the alkane of larger number of carbon atoms, because the solubility of the dye is higher, the desorption rate of the dye is faster and the diffusion coefficient is smaller than those in the smaller alkanes. But the energy required to separate the dye molecules from the alkane molecules is much higher because the interaction between the alkane molecule and the dye molecule become strong with the number of carbon atoms.