• BMB Reports
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• v.35 no.5
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• pp.508-512
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• 2002

Phospholipase C-gamma-2 ($PLC{\gamma}2$) activation is a key signaling event for many cell functions. In order to delineate the pathways that lead to $PLC{\gamma}2$ activation, we devised a quick method for obtaining sufficient $PLC{\gamma}2$. We obtained the full-length cDNA for human $PLC{\gamma}2$ and expressed it in E. coli using the expression vector pT5T. To enhance the protein expression, tandem AGG-AGG arginine codons at the amino acid positions 1204-1205 were replaced by CGG-CGG arginine codons. The protein expression was detected in a Western blot analysis by both anti-$PLC{\gamma}2$ antibodies and the antibodies that are raised against the tripeptide epitope (Glu-Glu-Phe) tag that are genetically-engineered to its carboxyl terminal. Crude lysates that were prepared from bacteria that express $PLC{\gamma}2$ were found to catalyze the hydrolysis of phosphatidylinositol 4,5 bisphosphate. Similar to previous reports on $PLC{\gamma}2$ that is isolated from mammalian tissue, the recombinant enzyme was $Ca^{2+}$ dependent with optimal activity at 1-10 uM $Ca^{2+}$.

• Journal of Microbiology and Biotechnology
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• v.20 no.4
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• pp.693-699
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• 2010

An antiproliferative ribonuclease with a new N-terminal sequence was purified from fruiting bodies of the edible wild mushroom Russula delica in this study. This novel ribonuclease was unadsorbed on DEAE-cellulose, but absorbed on SP-Sepharose and Q-Sepharose. It had a molecular mass of 14 kDa, as judged by fast protein liquid chromatography on Superdex 75 and SDS-polyacrylamide gel electrophoresis. Its optimal pH and optimal temperature were pH 5 and $60^{\circ}C$, respectively. The ranking of its activity toward various polyhomoribonucleotides was poly C> poly G>poly A>poly U. It could inhibit proliferation of HepG2 and MCF-7 cancer cells with an $IC_50$ value of $8.6\;{\mu}M$ and $7.2\;{\mu}M$, respectively. It was devoid of antifungal and HIV-1 reverse transcriptase inhibitory activity.

• The Journal of Korean Medicine
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• v.27 no.4
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• pp.105-115
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• 2006

Fucoidan has been shown to exhibit a host of biological activities, including anti-coagulant, anti-thrombotic, anti-tumourigenic, anti-inflammatory, anti-viral, anti-complementary and neuroprotective effects. In the present study, we attempted to determine the effects of Fucoidan on both apoptosis and cell proliferation in the hippocampal CA1 region and the dentate gyrus of gerbils after the induction of transient global ischemia. This experiment involved the use of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay as well as immunohistochemisty for caspase-3 and 5-bromo-2'-deoxyuridine (BrdU). The monosaccharide composition of the purified Fucoidan which had been extracted from Laminaria religiosa was utilized in this study. The present study clearly induces that apoptotic cell death and cell proliferation in the gerbil's hippocampal regions increased significantly following the induction of transient global ischemia and the results of this study also indicate that Fucoidan exerted a suppressive effect on this observed ischemia-induced increase in apoptosis within the CA1 and dentate gyrus, and also suppressed cell proliferation in the dentate gyrus.

• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.52-55
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• 2003

There is considerable evidence that ionizing radiation (IR) mediates checkpoint control, repair and cell death. In this study, we have used a high density microarray hybridization approach to characterize the transcriptional response of human breast carcinoma MCF-7 cell line to ${\gamma}$-radiation, such as 4 Gy 4 hr, 8 Gy 4 hr, and 8 Gy 12 hr. We found that exposure to ${\gamma}$-ray alters by at least a $log_2$ factor of 1.0 the expression of 115 known genes. Of the 66 genes affected by ${\gamma}$-radiation, 49 are down-regulated. In our results, the cellular response to irradiation includes induction of the c-jun and EGR1 early response genes. The present work has examined potential cytoplasmic signaling cascades that transduce IR-induced signals to the nucleus. 40S ribosomal protein s6 kinase modulates the activities of the mitogen activated protein kinase (MAPK) and c-Jun $NH_2$-terminal kinase (JNK1) cascades in human monocytic leukemia (U937/pREP4) cells. 14-3-3 family members are dimeric phosphoserine -binding proteins that participate in signal transduction and checkpoint control pathways.

• The Journal of Korean Medicine
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• v.29 no.2
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• pp.21-31
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• 2008

Backgrounds: Singihwan is used "to strengthen inborn energy" and we suspected a protective effect on brain neuron cells. Objectives: The aim of this study was to evaluate the effects of Singihwan (SGH) on traumatic brain injury-induced delayed apoptosis in rat hippocampal dentate gyrus. Methods: For a surgical induction of traumatic brain injury (TBI), a 5 mm diameter stainless rod was used to make traumatic attack from the surface of the brain used by an impactor. The protective effect of the aqueous extract of SGH against TBI in the rat hippocampal dentate gyrus was investigated by using step-down avoidance task, terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) assay, Bax immunohistochemistry, and 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. Results: The aqueous extract of SGH suppressed the TBI-induced increase in apoptosis and cell proliferation in the hippocampal dentate gyrus. Conclusions: It is possible that the aqueous extract of SGH has a neuroprotective effect on TBI-induced neuronal cell death.

• Journal of Microbiology and Biotechnology
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• v.16 no.11
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• pp.1832-1836
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• 2006

Mesorhizobium sp. LUK, which utilizes 3-amino-3-phenylpropionic acid as the sole source of nitrogen with high enantioselectivity (E(S)>100), was isolated using enrichment culture. The enzyme involved in the utilization of (S)-3-amino-3-phenylpropionic acid was confirmed to be a transaminase and was purified by 235-folds with a specific activity of 0.72 U/mg. The molecular weight of the purified protein was ca. 47 kDa and the active enzyme was determined as a dimer on gel filtration chromatography. The N-terminal sequence was obtained from the purified protein. Spontaneous decarboxylation of produced ${\beta}-keto$ acids was observed during the chiral resolution of 3-amino-3-phenylpropionic acid.

• Microbiology and Biotechnology Letters
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• v.21 no.6
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• pp.582-587
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• 1993

The extracellular alpha-amylase was purified to homogenity from the culture filtrate of starch grown Sch. castellii CBS 2863. The purified enzyme was glycoprotein with a molecular weight of about 56 kDa. The pH and temperature optimum were 5.5 and 40C, respectively. The enzyme was fairly stable up to 40C and at acid pH range (pH 4.0-7.0). The apparent Km and Vmax of the enzyme toward starch was 1.0mg/ml and 100U/mg protein, respectively. The analysis of amino acid composition was found to be acidic protein. The amino acid sequence of N-terminal peptide consisted of Asp-Val-Ser-Ser-Ala-X-X-Thr-Arg-Ser-Glu-Ser-Ile-Tyr.

• Proceedings of the Korea Port Economic Association Conference
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• 2007.07a
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• pp.493-514
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• 2007

A Port is, one of the important infrastructures, the terminal to connect between land and sea and exerts influences on the development of nation and local area. Accordingly government and privates are making an investment in port facilities in order to raise its competitive power. Due to the economic growth of China and the geographic advantage that Gunsan and Janghang port are close to China, recently traffic with China is rapidly increasing and the role of Gunsan & Janghang ports as a gateway port of west costbecame more important. There, however, remains that Gunsan and Janhang port still don't equipped with enough facilities and strategies to handle increasing traffic. The purpose of this paper is to analyze O/D data of Gunsan-Janghang Port and present the result of O/D as preliminary data. O/D data of Gunsan and Janghang had been analyzed by kinds of cargoes and from/to China's ports and this paper suggests to the competitive strategies of Gunsan and Janghang port to attract cargoes from/to China particularly.

• 한국정보통신설비학회:학술대회논문집
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• 2004.08a
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• pp.273-277
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• 2004

서울대학교와 KT는 연구 환경 조성과 U-Campus 시범 구축을 위해서 산학협력 협약을 하고, 서울대학교에 NESPOT 시설을 구축하였다. 본 논문은 서울대학교 내의 NESPOT 이용자들의 NESPOT 서비스 이용 패턴 및 무선랜의 트래픽 특성을 분석하기 위한 시스템의 설계와 구현에 대한 내용을 다룬다. NESPOT 트래픽 특성을 분석하기 위한 시스템은 TCPDUMP를 이용하여 백본 라우터로부터 네트워크 전체에 대한 정보를 획득하고, SNMP (Simple Network management Protocol)을 통해 AP로부터 무선랜 관련 정보를 얻는다. 그리고, NESPOT 사용자의 단말에 관련된 보다 구체적인 정보를 얻기 위해서 TIS (Terminal Information System)을 개발하였다.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.253-256
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• 1997

This paper describes a novel design method for compensating field time-constant of micro-synchronous machine so that its terminal flux can show the same characteristics as large-scale synchronous machine's. In addition to it, the suggested design method can determine the field time-constant regulator's parameters considered the nonlinearities of micro-synchronous machine such as saturation and loading effect. This method applied to 5kVA micro-synchronous machine, and the digital time-constant regulator with digital AVR were designed such that the short field time-constant, $T_{do}'=1.12\;sec$, can take on the large-scale synchronous machine time constant, $T_{do}'=1.47\;sec$. After determining the parameters of controllers, the real time digital time-constant regulator and digital AVR algorithm were implemented by using the PC with Penumum processor, and the usefulness of suggested real time digital time-constant regulator was verified by observing its good performance on the excitation of micro-synchronous machine.