• Reproductive and Developmental Biology
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• v.31 no.2
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• pp.127-131
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• 2007

Embryonic germ (EG) cells are undifferentiated stern cells isolated from cultured primordial germ cells (PGC). These cells share many characteristics with embryonic stem cells including morphology and pluripotency. Undifferentiated porcine EG cell lines demonstrating capacities of differentiation both in vitro and in vivo have been established. Since EG cells can be cultured indefinitely in an undifferentiated state, whereas somatic cells in primary culture are often unstable and have limited lifespan, EG cells may provide inexhaustible source of karyoplasts in nuclear transfer (NT). In this study the efficiencies of NT using porcine EG and fetal fibroblast cells were compared. Two different techniques were used to perform NT. With conventional NT procedure (Roslin method) involving fusion of donor cells with enucleated oocytes, the rates of development to the blastocyst stage in EG and somatic cell NT were 16.8% (59/351) and 14.5% (98/677), respectively. In piezo-driven microinjection (Honolulu method) of donor nuclei into enucleated oocytes, the rates of blastocyst formation in EG and somatic cell NT were 11.9% (15/126) and 9.4% (9/96), respectively. Regardless of NT methods used in this study, EG cell NT gave rise to comparable rate of blastocyst development to somatic cell NT. Overall, EG cells can be used as karyoplast donor in NT procedure, and embryos can be produced by EG cell NT that may be used as an alternative to conventional somatic cell NT.

• BMB Reports
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• v.29 no.3
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• pp.221-224
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• 1996

To examine the growth-phase dependent control of Escherichia coli rnpB gene we used a combination of Northern analysis for RNA determination and Southern analysis for plasmid DNA determination. The relative amounts of metabolically unstable transcript derived from the internally deleted rnpB gene harbored on a multicopy plasmid as well as the relative plasmid contents were measured by Northern analysis and Southern analysis, respectively, of total nucleic acids from E coli cells containing the plasmid. The relative transcription activity of the rnB was represented by a ratio of the relative amount of the transcript to that of the plasmid DNA during bacterial growth. The rnpB transcription increased rapidly with time during exponential growth, but started to decrease before the transition period of an exponential growing cell culture into the stationary phase. Although the expression pattern was similar to the changes of ${\beta}-galactosidase$ activity expressed from the lysogenic strain carrying the chromosomal rnpB-lacZ fusion which were shown in a previous work, the present data appears to represent a more actual growth-phase control of the rnpB transcription than the previous data by the ${\beta}-galactosidase$ assay. In addition the present method described for a direct analysis of both RNA and plasmid DNA provides a rapid and efficient method that can applied to an examination of transcription control by using a multicopy plasmid.

• Journal of Microbiology and Biotechnology
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• v.11 no.1
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• pp.131-137
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• 2001

Previous work has identified that only the catabolite responsive element A (creA; previously called cre-2) out of two potential cre sequences (cre-1: nucleotide +160 to +173 and cre-2: +173 to +186), recognized within the coding region of the xylanaseA gene (xynA) of Bacillus stearothermophilus No.236, was actually, was actually involved in the carbon catabolite repression(CCR) of xynA expression in B. subtilis. However, the level of CCR of xynA expression in the original B.stearothermophilus No.236 strain (70-fold repression). Therefore, to search for an additional cre element in the promoter region, the upstream region of the xynA gene was subcloned by chromosome walking, and as a result, another potential cre element (nucleotide -124∼-137; designated creB) was recognized in this region. The cre-like sequence revealed a high homology to the cre consensus sequence. The xylanase activity of B. subtilis MW15 bearing pWPBR14 (containing creA and creB) cultured in a medium containing xylose as the sole carbon source was about 7.7 times higher than that observed for the same culture containing glucose. B. subtilis MW15 bearing pWPBR23 (containing only creA) produced an activity about 2.4 times higher. This pattern of CCR was confirmed using derivatives of xynA::aprA fusion plasmids. Furthermore, a measurement of the amounts of the xynA transcript showed a similar pattern as that for the production of xylanase. In addition, the synthesis of xylanase in B. subtilis QB7115 [a catabolite control protein A (ccpA) mutant strain] carrying pWPBR14 was almost completely relieved from glucose repression. Together, these results lead to a conclusion that the CCR of the expression of the xynA gene is mediated by CcpA binding at creA and creB sites in B. subtilis.

• Journal of Korean Society for Quality Management
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• v.45 no.2
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• pp.247-260
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• 2017

Purpose: The study is aimed to identify the national cultural dimensions that are affecting the quality management (QM) maturity level and the project quality performance, and analyze their relationships. Methods: This study collected the data of QM Maturity level based on Crosby's QM maturity model and the project quality performance using the Iron Triangle (Quality, Time/Schedule and Cost) from the employees who are participating in the ITER Project across the major 8 countries (China, France, Italy, Japan, Korea, Russia, U.K. and U.S.A.). Three research hypotheses are proposed concerning the national cultural dimensions in this study and Hofstede's five cultural dimensions framework are used for the statistical test. Results: The results are two folds in the study: First, there is a significant positive correlation between the QM maturity level and the project quality performance. Second, three cultural dimensions (Collectivism, Large Power Distance and Strong Uncertainty Avoidance) and five cultural dimensions (Collectivism, Large Power Distance, Strong Uncertainty Avoidance, Feminity and Long Term Orientation) have a positive impact on the QM maturity level and the project quality performance respectively. Conclusion: From the results, the understanding and consideration of the culture difference among the countries participating International Collaboration R&D project are recommended.

• Journal of the Korean Society for information Management
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• v.28 no.2
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• pp.79-96
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• 2011

Despite the widespread use, critics claim that citation analysis has serious limitations in evaluating the research performance of scholars. First, conventional citation analysis methods yield one-dimensional and sometimes misleading evaluation as a result of not taking into account differences in citation quality, not filtering out citation noise such as self-citations, and not considering non-numeric aspects of citations such as language, culture, and time. Second, the citation database coverage of today is disjoint and incomplete, which can result in conflicting quality assessment outcomes across different data sources. This paper discuss the findings from a citation analysis study that measured the impact of scholarly publications based on the data mined from Web of Science, Scopus, and Google Scholar, and briefly describes a work-in-progress prototype system called CiteSearch, which is designed to overcome the weaknesses of existing citation analysis methods with a robust citation-based quality assessment approach.

• Parasites, Hosts and Diseases
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• v.44 no.4 s.140
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• pp.303-312
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• 2006

Interactions between GRA proteins of dense granules in Toxoplasma gondii and host cell proteins were analyzed by yeast two-hybrid technique. The cMyc-GRA fusion proteins expressed from pGBKT7 plasmid in Y187 yeast were bound to host cell proteins from pGADT7-Rec-HeLa cDNA library transformed to AH109 yeast by mating method. By the selection procedures, a total of 939 colonies of the SD/-AHLT culture, 348 colonies of the $X-\alpha-gal$ positive and PCR, 157 colonies of the $X-\beta-gal$ assay were chosen for sequencing the cDNA and finally 90 colonies containing ORF were selected to analyze the interactions. GRA proteins interacted with a variety of host cell proteins such as enzymes, structural and functional proteins of organellar proteins of broad spectrum. Several specific bindings of each GRA protein to host proteins were discussed presumptively the role of GRA proteins after secreting into the parasitophorous vacuoles (PV) and the PV membrane in the parasitism of this parasite.

• Journal of the Korea Fashion and Costume Design Association
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• v.6 no.1
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• pp.13-24
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• 2004

This study was analyzed three basic patterns of the Islamic arts. These are natural flora, geometrical and calligraphy pattern. Islamic belief in Aniconism, doctrine of unity and worship of arabic language demanded delicate, decorative, and abstract patterns instead of patterns of real image. Natural flora pattern was classified into arabesque and various flower patterns. Muhammad commands that "The artist who fashions a representation of living things is competitor of God and therefore destined to eternal damnation, so if you want to represent living things, you should only depict flowers and trees". Then the natural flora patterns developed into main Islamic pattern. Geometric pattern was composed of geometrical elements like, circle, trigon, square, rectangle, pentagon, hexagon, octagon or other polygons, stars or motifs with straight or curved lines. Circle symbolized ′celestial′ sphere and crystal of the lower octagon symbolized ′earthly existence′. Therefore if the circle join with the octagons, it means fusion of celestial and earthly existence. Another important influence on the Islamic art was the calligraphy pattern, the writing of Arabic language. The major language of calligraphy pattern was Arabic script and often Persian script. Calligraphy pattern was composed of Kufic and Cursive script. The cursive script was developed various forms. The Islamic tenet prohibit depiction of sacred images, the sacred Arabic calligraphy such as ′Alla′ or ′Mohammad′ was substituted of them. And the content of calligraphy pattern was used with Quranic phrases. The aesthetics of Islamic patterns analyzed aesthetic of ′rhythmic lines′, aesthetic of ′unity in multiplicity′, aesthetic of tessellation and aesthetic of harmony. On the textiles of the Islamic culture, the arabesque, floral, geometric and calligraphy patterns were frequently used.

• BMB Reports
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• v.33 no.4
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• pp.294-299
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• 2000

Proteolytic processing of the dengue virus serotype 2 polyprotein precursor is catalyzed by a host signal peptidase and a virus encoded two-component protease consisting of the nonstructural proteins, NS2B and NS3. We expressed in Escherichia coli the NS2B, NS3(pro) and NS2B-NS3 proteins from the dengue virus type 2 strain 16681 as N-terminal fusions with a hexahistidine affinity tag under the control of the inducible trc promoter. All fusion proteins were purified to >90% purity by detergent extraction of inclusion bodies and a single step metal chelate chromatography. Proteins were refolded on-column and recovered with yields of 0.5, 6.0 and 1.0 mg/l of E. coli culture that was grown to $OD_{600}=1.0$ for NS2B, NS3(pro) and NS2B-NS3, respectively. Purified proteins gave strong signals in Western blots using $Ni^{2+}-nitrilotriacetic$ acid as a probe for the presence of the polyHis tag. During the purification process, $(His)_{6}NS2B-NS3$ was apparently not autoproteolytically cleaved at the NS2B/NS3 site.

• Microbiology and Biotechnology Letters
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• v.28 no.2
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• pp.71-79
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• 2000

Two typess of copolyesters, poly(3-hydroxybutyric acid-co-4-hydroxy-butyric acid)[P(3HB-co-4HB] and poly(3-hydroxybutyric acid-co-3-hydroxyvaleric acid)[P(3HB-co-3HV)], with various monomer ratios and different degree of microstructural heterogeneity were synthesized from Ralstonia eutropha H16 and Hydrogenophaga pseudoflava by using ${\gamma}$-butyrolactone and ${\gamma}$-valerolactone, respectively. The two bacteria showed a large difference in the utilization of ${\gamma}$-butyrolactone for cell growth and PHA synthesis. H. pseudoflava synthesized P(3HB-co-4HB) copolyesters with a wide range of 4HB content from 13 to 96 mol% depending on culture conditions, whiel R. eutropha H16 was able to synthesize the copolyesters containing less than 20 mol% of 4HB. An increase in the 4HB content in the P(3HB-co-4HB) copolyesters synthesized by H. pseud-oflava induced an lowering of their melting temperatures as well as their enthalpies of fusion. The increase in the 4HB content, however, increased the rate of degradation by an extracellular P(3HB) depolymerase. NMR spectros-copy and differential scanning calorimetry showed that the P(3HB-co-4HB) copolyesters from H. pseudoflava were generally microstructurally heterogeneous. The P(3HB-co-4HB) copolyesters) synthesized by R. eutropha H16 were rather random copolymers showing less microstructural heterogeneity than those synthesized by H. pseudoflava. The NMR D value analysis suggested that the monomer distribution of the P(3HB-co-3HV) copolymers from the two bacteria were relatively random.

• Journal of fish pathology
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• v.19 no.3
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• pp.277-284
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• 2006

Application of wood vinegar in fish farms has been used for the disinfection of pathogenic microorganisms and the treatment of infectious diseases. This study was performed to know the acute toxicity of wood vinegar to carp Cyprinus carpio, flounder Paralichyhus olivaceus, rock fish Sebastes schlegeli and black sea bream Pagrus major. The 24 hr, 48 hr and 96 hr LC50 respectively were: carp 1243, 1143 and 1016 ppm; flounder 1397, 1253 and 1226 ppm; rock fish 1058, 993 and 967 ppm; and black sea bream 650, 616 and 596 ppm. Death and survival of fish exposed to lethal concentrations of wood vinegar were apparently related to massive necrosis, fusion and epithelial lifting of gill lamellar epithelium, suggesting the osmotic imbalance and lack of oxygen uptake.