• Animal cells and systems
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• v.5 no.2
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• pp.145-151
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• 2001

p62 is a phosphotyrosine-independent ligand of the SH2 domain of $p56^{Ick}$, a T-cell specific Src family tyrosine kinase. Recently p62 has been shown to interact with a number of proteins, such as $PKC\varsigma$ and ubiquitin, and implicated in important cellular functions such as cell proliferation. Since the two p62 interacting proteins, $p56^{Ick}$ and $PKC\varsigma$, have been reported to play roles in cell death, 1 have addressed the potential role of p62 during apoptosis in Jurkat cells in this study. Herein 1 show that p62 was specifically cleaved into two peptides by a caspase-3-like activity during Fas-receptor mediated apoptosis in Jurkat cells. This cleavage generated two fragments with molecular weights of about 35 kDa that differed in subcellular localizations. The N-terminal cleaved fragment was present in the detergent-insoluble fraction whereas the C-terminal fragment was found in the detergent-soluble fraction. In addition, the C-terminal fragment appeared to be subjected to further degradation as apoptosis prolonged. Moreover, overexpression of p62 in Jurkat cells attenuated the Fas receptor mediated apoptosis, suggesting that p62 is involved in apoptotic signal transduction pathway in lymphocytes.

• Animal cells and systems
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• v.3 no.3
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• pp.331-336
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• 1999

p56$^{Ick}$, a cytoplasmic protein tyrosine kinase of the src family, is non-covalently associated with the cell surface coreceptors CD4 and CD8, which are expressed on thymocytes and mature T cells. The coreceptor protein plays an important role during the differentiation of thymocytes and the activation of T cells. DNA constructs were designed to study the roles of CD4 and CD8 during the differentiation of thymocytes. One is a chimeric cDNA which consists of coding regions for the extracellular domain of CD8a and the transmembrane and cytoplasmic domain of CD4. The other is the same chimeric cDNA but with a point mutation converting Cys to Ala in the Ick-binding site to disrupt the association. We confirmed that the CD8a/CD4 chimeric molecule bound to Ick more efficiently than the wild type CD8a protein. However, the chimeric protein with the Cys$leftrightarro$Ala mutation did not associate with Ick. The results suggest a possibility that the CD8a/CD4 chimeric protein may behave like a CD4 protein in associating with Ick and that it may deliver a signal inside the cell in a similar manner, Analysing effects of the mutant CD8a/CD4 chimeric protein expression in developing thymocytes will elucidate the role of Ick during the determination of CD4/CD8 cell lineages.

• Bulletin of the Korean Chemical Society
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• v.32 no.12
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• pp.4352-4360
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• 2011

A four dimensional quantitative structure activity relationship analysis was applied to a series of 50 flavonoid inhibitors of $p56^{lck}$ protein tyrosine kinase by the molecular comparative electron topological method. It was found that the -log (IC50) values of the compounds were highly dependent on the topology, size and electrostatic character of the substituents at seven positions of the flavonoid scaffold in this study. Depending on the negative or positive charge of the groups correctly embedded in these substituents, three-dimensional bio-structure to increase or decrease -log (IC50) values in the training set of 39 compounds was predicted. The test set of 11 compounds was used to evaluate the predictivity of the model. To generate 4D-QSAR model, the defined function groups and pharmacophore used as topological descriptors in the calculation of activity were of sufficient statistical quality ($R^2$ = 0.72 and $Q^2$ = 0.69). Ligand docking approach by using Dock 6.0. These compounds include many flavonoid analogs, They were docked onto human families of p56lck PTKs retrieved from the Protein Data Bank, 1lkl.pdb.

• Animal cells and systems
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• v.8 no.2
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• pp.125-133
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• 2004

We have extended our previous work that cross-linking CD4 molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$We have extended our previous work that cross-linking CD$4^+$ molecules using specific MAb induced antigen nonspecific, MHC unrestricted killing of virally infected target cells by CD$4^+$ T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD$4^+$T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4 molecules. The CD$4^+$cross-linking failed to induce effector cell proliferation or the transcription of TNF${\beta}$ Upregulation of TNF${\beta}$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF${\beta}$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased p$56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.T cells. The killing activity of antibody activated CD$4^+$T cells was completely blocked by herbimycin A, a protein tyrosine kinase (PTK) inhibitor, but not by bisindolylamaleimide, a protein kinase C (PKC) inhibitor. Herbimycin A treated human or bovine peripheral blood CD4T cells lacked PTK activity and failed to kill virally infected target cells even after cross-linking of CD4molecules. The CD4 cross-linking failed to induce effector cell proliferation or the transcription of TNF$\beta$. Upregulation of TNF$\beta$ was induced by incubating the antibody activated effector cells with BHV-1 infected D17 target cells for 10 h. Anti-TNF$\beta$ antibody partially abolished (13-44%) the direct effector cell-mediated antiviral cytotoxicity. However, this antibody neutralized 70 to 100% of antiviral activity of effector and target cell culture supernatants against BHV-1 infected D17 cells. The inhibition level of the antiviral activity by the antibody was dependent on the effector and target cell ratio. These results support the hypothesis that increased $56^ICK enzyme activity in effector cells transduces a signal critical for effector cell recognition of viral glycoproteins expressed on the target cells. Following target cell recognition, lytic cytokines known to participate in target cell killing were produced. A better understanding of the killing activity displayed by CD$4^+$T lymphocytes following surface receptor cross-linking will provide insight into the mechanisms of cytotoxic activity directed toward virally-infected cells.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.51-56
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• 2006

Biases embedded in numerical weather precipitation forecasts by the RDAPS model was determined, quantified and corrected. The ultimate objective is to eventually enhance the reliability of reservoir operation by Korean Water Resources Corporation (KOWACO), which is based on precipitation-driven forecasts of stream flow. Statistical post-processing, so called MOS (Model Output Statistics) was applied to RDAPS to improve their performance. The Artificial Neural Nwetwork (ANN) model was applied for 4 cases of 'Probability of Precipitation (PoP) for wet and dry season' and 'Quantitative Precipitation Forecasts (QPF) for wet and dry season'. The reduction on the large systematic bias was especially remarkable. The performance of both networks may be improved by retraining, probably every month. In addition, it is expected that performance of the networks will improve once atmospheric profile data are incorporated in the analysis. The key to the optimal performance of ANN is to have a large data set relevant to the predictand variable. The more complex the process to be modeled by the ANN, the larger the data set needs to be.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.56 no.2
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• pp.109-114
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• 2007

This paper summarize about the auxiliary electrode measured a ground resistance. The method to measure a ground resistance is the fall-of-potential method to using an auxiliary electrode. And an auxiliary electrode must be set up on the ground. Today it is so difficult to set up the auxiliary electrode on the ground because of many concrete building and many paved roads. So this paper is regarding a trust analysis of the ground resistance measurement by the substitute auxiliary electrode. It substituted a iron structure around the building, a neutral line multiplex ground to earth, a wire net for auxiliary electrode. This information is confirmed bv compared with the measurement value.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1555-1557
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• 2001

To compare the lightning impulse measurement capabilities of high voltage laboratory, a lightning impulse voltage measuring system from HUT is circulated around the world. This paper presents test results after second round of this worldwide exercise. KERI's impulse voltage measuring system compared with the circulating reference measuring system from HUT at voltage levels of 80, 160, 240, 320 and 400 kV. Three impulse shapes were used, i.e. full smooth lightning impulse with both short (0.84 $\sim$ 0.95 ${\mu}s$) and long front (1.45 $\sim$ 1.56 ${\mu}s$), and chopped impulse with time to chopped impuse. Impulse peak value ($U_p$) and time parameters ($T_1$, $T_2$ and $T_c$) according to IEC 60060-1 were compared.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1017-1025
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• 2016

This study was performed in order to investigate changes in platycosides, as well as antimicrobial activities of bronchus diseases-inducing bacteria (Corynebacterium diphtheriae, Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus pyogenes) of Platycodon grandiflorum root (PGR) fermented by lactic acid bacteria (Leuconostoc mesenteroides N12-4, Leuc. mesenteroides N58-5, Lactobacillus plantarum N76-10, L. plantarum N56-12, Lactobacillus brevis N70-9, and L. brevis E3-8). Growth of L. plantarum on PGR was most active during lactic acid fermentation using different strains. Total platycoside, platycoside E, platycodin A, polygalacin $D_2$, polygalacin D, and diapioplatyco-side E contents of PGR fermented for 96 h at $37^{\circ}C$ by Leuc. mesenteroides and L. plantarum increased, whereas contents of platycodin D and platycodin $D_3$ were reduced. The antimicrobial activity on PGR fermented by L. plantarum N56-12 exhibited strong microbial proliferation for all four kinds of bronchus disease-inducing bacteria and was higher than that of non-fermented PGR extract. MIC of fermented PGR extract by L. plantarum N56-12 on C. diphtheriae, K. pneumoniae, S. aureus, and S. pyogenes were 45, 10, 50, and 25 mg/mL, respectively. Thus, this result shows that the antimicrobial activities of bronchus disease-inducing bacteria and platycoside content of PGR by L. plantarum N56-12 were higher than that of non-fermented PGR extract.

• Clinical and Experimental Pediatrics
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• v.61 no.6
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• pp.187-193
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• 2018

Purpose: The efficacy of percutaneous stent implantation for congenital heart disease (CHD) in Korea, where stent availability is limited, has not been determined. This study evaluated the acute and midterm results of stent implantation in different CHD subgroups. Methods: Stents were implanted in 75 patients with 81 lesions: (1) pulmonary artery stenosis (PAS) group, 56 lesions in 51 patients; (2) coarctation of the aorta (CoA) group, 5 lesions in 5 patients; (3) Fontan group, 13 lesions in 12 patients; (4) ductal stent group, 3 lesions in 3 patients; and (5) other CHD group, 4 lesions in 4 patients. Mean follow-up duration was 2.1 years (0.1-4 years). Medical records were reviewed retrospectively. Results: The minimum lumen diameter (MLD) in PAS and CoA increased from $5.0{\pm}1.9mm$ and $8.4{\pm}1.6mm$ to $10.1{\pm}3.6mm$ and $12.3{\pm}2.5mm$, respectively (P<0.01). In the PAS group, pressure gradient decreased from $25.7{\pm}15.6mmHg$ to $10.4{\pm}10.1mmHg$, and right ventricular to aortic pressure ratio from $0.56{\pm}0.21$ to $0.46{\pm}0.19$. In the CoA group, the pressure gradient decreased from $50{\pm}33mmHg$ to $17{\pm}8mmHg$. In the ductal stent group, the MLD of the ductus increased from 2.3 mm to 4.3 mm and arterial oxygen saturation from 40%-70% to 90%. No deaths were associated with stent implantation. Stent migration occurred in 3 patients, but repositioning was successful in all. Stent redilation was performed successfully in 26 cases after $29{\pm}12months$. Conclusion: Percutaneous stent implantation was safe and effective, with acceptable short and mid-term outcomes in Korean CHD patients.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.851-858
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• 2016

The effective components of Schisandra chinensis are lignans (schizandrins and gomisins), which have various physiological functionalities such as anti-cancer, anti-inflammatory, and antioxidant activities. This study was carried out to determine the different parts of fruits in Schisandra chinensis to elevate their usefulness. Schisandra chinensis was separated into skin (epicarp), pulp (mesocarp), and seeds, and raw Omija and hot-dried Omija (HDO) were used as control. The most abundant component was nitrogen free extract (6.88~56.70%) followed by crude lipids (1.65~19.04%). The main mineral was K (383.10~2,024.10 mg/100 g), except in seeds where P was the main mineral. The main lignan in all parts of fruit was schizandrin, and the highest content of schizandrin was 9.46 mg/g in dried seeds. Total lignan content was 25.97 mg/g and 14.97 mg/g in dried seeds and HDO, respectively. A total of 17 components of fatty acids in seeds and HDO were detected, of which linoleic acid (72.66~73.78%), oleic acid (14.78~17.39%), palmitic acid (2.88~3.54%), and capric acid (1.70~4.93%) were determined as the major components. Main lignans and fatty acids of Schisandra chinensis fruit contain mainly seeds. Therefore, it is more efficient to use seeds than pulp and extract of fruit itself to use the components of Omija.