• BMB Reports
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• v.31 no.4
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• pp.370-376
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• 1998

Src-Homology 2 (SH2) domains have a capacity to bind phosphotyrosine-containing sequence context and play essential roles in various cellular signaling pathways. Due to the specific nature of the binding between SH2 domains and their counterpart proteins, inhibitors of SID domain binding have drawn extensive attention as a potential candidate for therapeutic agents. Here, we describe the binding assay system to screen for the ligands or blockers of the SH2 domains with an emphasis on the $p56^{lck}$ SH2 domain. In our assay system, SID domains expressed and purified as fusion proteins to Glutathione-S-transferase (GST) were covalently attached to 96-well microtitre plates through amide bond formation, which were subsequently allowed to bind the biotinylated phosphotyrosine (pY)containing synthetic pep tides. The binding of biotinylated pY peptides was detected by the horseradish peroxidase (HRP)-conjugated streptavidin. Using the various combinations of SH2 domain-pY peptides, we observed that: (1) The binding of pY-peptides to its counterpart SH2 domain is concentration-dependent and saturable; (2) The binding is highly specific for a particular combination of SH2 domain-pY peptide pair; and (3) The binding of Lck SH2-cognate pY-peptides is specifically competed by the nonbiotinylated peptides with expected relative affinity. These results indicate that the established assay system detects the SH2-pY peptide interaction with reproducible sensitivity and specificity and is suitable for screening the specific inhibitors of $p56^{lck}$ SH2 function.

• Journal of Science of Art and Design
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• v.8
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• pp.267-296
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• 2005

Typography, as the median for communication, has expanded its roles according the attributes of the media where it Is used, and the change of media follwing the change of times is presenting new directions to the field of typography. The attempts of 20C experimental typography prioritize visual formativeness, free typography and language started to appear on printed matters and different kinds of prints put pep in magazines. Thus, experiments in the aspects of effective delivery of inpormation that letters have and aesthetic side of shapes of letter are continuing. Today with the appearance of multimedia, development of visual colture and rapid development of digital technology, the range of experimental typography has expanded even wider and therefore, different kinds of expressions became possible. As seen above, unlike the existing static printed media that carries linguistic information only, letters in the multimedia environment is shown in the movie titles, TV or web not only as a basic visual media such as type and image, but as a dynamic and complex factor that contains additional information of motion and sound factor. This study will attempt to find the historic context of focus of moment from the kinetic art and define the moving letters as kinetic typography. Therefore, this paper will have an understanding on kinetic typography's background, concept and characteristics following the change of communication environment in the multimedia era and tried to study the basic theories of kinetic typography and the information delivery and imagery function of letters. Also, this paper attempted to carry out a study on whether kinetic typography is delivering information smoothly from the aspect of communication through the image role as delivering information by studying major works of artists who have influenced kinetic typography. Based on this study, I would like to suggest new direction for effective delivery of information and value of use.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.11
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• pp.5458-5464
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• 2012

In LTE-Advanced that different networks coexist, it is considered that it is actually difficult to provide service continuity with a procedural and static control method applied to the existing voice service. This research suggests a resource management framework to support the service continuity effectively based on QoS support. In other words, as context information of mobile terminal and base station changes, set-up of related functions such as ISHO, cell selection, source allocation, load control, and QoS mapping is adapted; each function fits into the change, exchanges the process of reorganization, and interacts; these actions go toward to satisfy service continuity. For this aim, the sequence diagram between the function modules for supporting four kind of ISHO is described and then a scenario for ISHO is considered.

• Molecular & Cellular Toxicology
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• v.4 no.3
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• pp.177-182
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• 2008

Caveolin proteins are mediators of cell death or the survival of injured cells, and they are inhibitors of various signaling pathways. The expression of caveolin-, which is involved in the protein kinase A (PKA) signaling pathway, was examined in the differentiated mouse vestibular cell line UB/UE-1 after gentamicin ototoxicity. Caveolae in the vestibular hair cell of healthy guinea pigs were observed through an electron microscope. UB/UE-1 cells were cultured at 95% $CO_2$ with 5% $O_2$ at $33^{\circ}C$ for 48 hours and at 95% $CO_2$ with 5% $O_2$ at $39^{\circ}C$ for 24 hours for differentiation. Cells were treated with 1 mM gentamicin, 0.02 mM H89 (PKA inhibitor), and then incubated for 24 hours. Caveolin-1 expression was examined by western blotting and PKA activity by a $PepTag^{(R)}$ assay. Caveolae were observed in the vestibular hair cells of healthy guinea pigs by electron microscopy. Caveolin-1 was expressed spontaneously in differentiated UB/UE-1 cells and increased after gentamicin treatment. PKA was also over-activated by gentamicin treatment. Both gentamicin-induced caveolin-1 expression and PKA over-activation were inhibited by H89. These results indicate that gentamicin-induced caveolin-1 expression is mediated by the PKA signaling pathway. We conclude that caveolae/ caveolin activity, induced via a PKA signaling pathway, may be one of the mechanisms of gentamicin-induced ototoxicity.

• Journal of Microbiology and Biotechnology
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• v.16 no.6
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• pp.870-879
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• 2006

The present study describes the formation of succinic acid by a nonvirulent, highly osmotolerant Klebsiella pneumoniae strain SAP (succinic acid producer), its profile of metabolites, and enzymes of the succinate production pathway. The strain produced succinate along with other metabolites such as lactate, acetate, and ethanol under aerobic as well as anaerobic growth conditions. The yield of succinate was higher in the presence of $MgCO_3$ under $N_2$ atmosphere as compared with that under $CO_2$ atmosphere. Analysis of intracellular metabolites showed the presence of a smaller PEP pool than that of pyruvate. Oxaloacetate, citrate, and $\alpha$-ketoglutarate pools were considerably larger than those of isocitrate and fumarate. In order to understand the synthesis of succinate, the enzymes involved in end-product formation were studied. Levels of phosphoenolpyruvate carboxykinase, fumarate reductase, pyruvate kinase, and acetate kinase were higher under anaerobic growth conditions. Based on the profiles of the metabolites and enzymes, it was concluded that the synthesis of succinate took place via oxaloacetate, malate, and fumarate in the strain under anaerobic growth conditions. The strain SAP showed potential for the bioconversion of fumarate to succinate under $N_2$ atmosphere in the presence of $MgCO_3$. At an initial fumarate concentration of 10 g/l, 7.1 g/l fumarate was converted to 7 g/l succinate with a molar conversion efficiency of 97.3%. The conversion efficiency and succinate yield were increased in the presence of glucose. Cells grown on fumarate contained an 18-fold higher fumarate reductase activity as compared with the activity obtained when grown on glucose.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1177-1182
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• 2012

Protein kinase C (PKC) has been implicated in carcinogenesis and displays variable expression profiles during cancer progression. Studies of dietary phytochemicals on cancer signalling pathway regulation have been conducted to search for potent signalling regulatory agents. The present study was designed to evaluate any suppressive effect of maslinic acid on PKC expression in human B-lymphoblastoid cells (Raji cells), and to identify the PKC isoforms expressed. Effects of maslinic acid on PKC activity were determined using a PepTag$^{(R)}$ assay for non-radioactive detection of PKC. The highest expression in Raji cells was obtained at 20 nM PMA induced for 6 hours. Suppressive effects of maslinic acid were compared with those of four PKC inhibitors (H-7, rottlerin, sphingosine, staurosporine) and two triterpenes (oleanolic acid and ursolic acid). The $IC_{50}$ values achieved for maslinic acid, staurosporine, H-7, sphingosine, rottlerin, ursolic acid and oleanolic acid were 11.52, 0.011, 0.767, 2.45, 5.46, 27.93 and $39.29\;{\mu}M$, respectively. Four PKC isoforms, PKC ${\beta}I$, ${\beta}II$, ${\delta}$, and ${\zeta}$, were identified in Raji cells via western blotting. Maslinic acid suppressed the expression of PKC ${\beta}I$, ${\delta}$, and ${\zeta}$ in a concentration-dependent manner. These preliminary results suggest promising suppressive effects of maslinic acid on PKC activity in Raji cells. Maslinic acid could be a potent cancer chemopreventive agent that may be involved in regulating many downstream signalling pathways that are activated through PKC receptors.

• Macromolecular Research
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• v.17 no.7
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• pp.458-463
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• 2009

Polyurethane (PU) is widely used as a cardiovascular biomaterial due to its good mechanical properties and hemocompatibility, but it is not adhesive to endothelial cells (ECs). Cell adhesive peptides, GRGDS and YIGSR, were found to promote adhesion and spreading of ECs and showed a synergistic effect when both of them were used. In this study, a surface modification was designed to fabricate an EC-active PU surface capable of promoting endothelialization using the peptides and poly(ethylene glycol) (PEG) spacer, The modified PU surfaces were characterized in vitro. The density of the grafted PEG on the PU surface was measured by acid-base back titration to the terminal-free isocyanate groups. The successful immobilization of pep tides was confirmed by amino acid analysis, following hydrolysis, and contact angle measurement. The uniform distribution of peptides on the surface was observed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). To evaluate the EC adhesive property, cell viability test using human umbilical vein EC (HUVEC) was investigated in vitro and enhanced endothelialization was characterized by the introduction of cell adhesive peptides, GRGDS and YIGSR, and PEG spacer. Therefore, GRGDS and YIGSR co-immobilized PU surfaces can be applied to an EC-specific vascular graft with long-term patency by endothelialization.

• Archives of Pharmacal Research
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• v.18 no.1
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• pp.12-17
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• 1995

It is essential to clone the preptide transporter in order to obtain better understanding of its molecular structure, regulation, and substrate specificity. Characteristics of an endogenous peptide transporter in oocytes were studied along with expression of an exogenous protor/peptide cotransporter from rabbit intestine. And further efforts toward cloning the transporter were performed. The presence of an endogenous peptide transporter was detected in Xenopus laevis oocytes by measuring the uptake of $0.25/{mu}M(10{\;}{\mu}Ci/ml)[^3H]$-glycylsarcosine (Gly-Sar) at pH 5.5 with or without inhibitors. Yptake of Gly-Sae in oocytes was significantly inhibited by $25{\mu}M$ glycine nd sarcosine. This result suggests that a selective transporter is involved in the endogneous uptake of dipeptides. Collagenase treatment of oocytes used to strip oocytes from ovarian follicles did not affect the Gly-Sar uptake. Changing pH from 5.5 to 7.5 did not affect the Gly-Sae uptake significantly, suggesting no depedence of the endogenous transporter on a transmembrane proton gradient. An exogenous $H^+/pep-tide$ contransported was expressed after microinjection of polyadenylated messenger ribonucleic acid $[poly(A)^+ -mRNA]$ obtained from rabbit small intestine. The Gly-Sar uptake in mRNA-injected oocytes was 9 times thigher than that in water-injected oocyltes. Thus, frog occytes can be utilized fro expression cloning of the genes encoding intestinal $H^+$peptide contransporters. Size fractionation of mRNA was successfully obtained using this technique.

• Steel and Composite Structures
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• v.10 no.3
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• pp.207-222
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• 2010

Fire incident in buildings is common, so the fire safety design of the framed structure is imperative, especially for the unprotected or partly protected bare steel frames. However, software for structural fire analysis is not widely available. As a result, the performance-based structural fire design is urged on the basis of using user-friendly and conventional nonlinear computer analysis programs so that engineers do not need to acquire new structural analysis software for structural fire analysis and design. The tool is desired to have the capacity of simulating the different fire scenarios and associated detrimental effects efficiently, which includes second-order P-D and P-d effects and material yielding. Also the nonlinear behaviour of large-scale structure becomes complicated when under fire, and thus its simulation relies on an efficient and effective numerical analysis to cope with intricate nonlinear effects due to fire. To this end, the present fire study utilizes a second-order elastic/plastic analysis software NIDA to predict structural behaviour of bare steel framed structures at elevated temperatures. This fire study considers thermal expansion and material degradation due to heating. Degradation of material strength with increasing temperature is included by a set of temperature-stress-strain curves according to BS5950 Part 8 mainly, which implicitly allows for creep deformation. This finite element stiffness formulation of beam-column elements is derived from the fifth-order PEP element which facilitates the computer modeling by one member per element. The Newton-Raphson method is used in the nonlinear solution procedure in order to trace the nonlinear equilibrium path at specified elevated temperatures. Several numerical and experimental verifications of framed structures are presented and compared against solutions in literature. The proposed method permits engineers to adopt the performance-based structural fire analysis and design using typical second-order nonlinear structural analysis software.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.34 no.4
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• pp.49-56
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• 2011

The Project of Jordan Research and Training Reactor (JRTR) officially launched in Aug. 2010. JRTR is the first made-in-Korea nuclear system to be built abroad by year 2015, and Korea Atomic Energy Research Institute (KAERI) is responsible for the design of major systems including the reactor core. While the PDCS (Project Document Control System) being operated by EPC company controls all the documents of the whole Project, KAERI is supposed to have its own system for KAERI documents. Meeting such a need; KAERI has implemented a document control for the JRTR Project into already existing ANSIM (KAERI Advanced Nuclear Safety Information Management) system. The documents of JRTR project to be controlled are defined in the PPM (Project Procedures Manual), QAP (Quality Assurance Procedure) and PEP (Project Execution Program). The ANSIM consists of the document management holder, document container holder and organization management holder. The document management holder, which is the most important part of ANSIM-JRTR, consists of the DDA (Document Distribution for Agreement), IOC (Inter-office Correspondence), PM Memo. (Project Manager Memorandum) and cover sheets of design documents. Other materials such as meeting minutes, sub-department materials and design information materials are stored in an independent COP (Community of Practice). This established computerized document control system, ANSIM, could lessen a burden for project management team and enhance the productivity as well.