• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.309-314
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• 2009

New poly(arylene-ethynylene)s with silicon-containing ferrocene moiety in the polymer main chain were synthesized via the C-C bond forming reactions of 1,1´-bis(ethynyldimethylsilyl)ferrocene and various aromatic dihalides in high yields. The aromatic dihalides include 1,4-dibromobenzene, 4,4´-dibromobiphenyl, 9,10-dibromoanthracene, 2,5-dibromopyridine, 2,5-dibromothiophene, and 2,6-diiodo-4-nitroaniline. The polymer structures and properties were characterized by such instrumental methods as NMR $(^1H-,\;^{13}C-,\;and\;^{29}Si-)$, IR, UV-visible spectroscopies and TGA/DSC. The spectral data indicated that the present polymers have the regular alternating structure of 1,1´-bis(ethynyldimethylsilyl)ferrocenylene and arylene units. The resulting polymers were completely soluble in such organic solvents as methylene chloride, chloroform, benzene, chlorobenzene, and THF. The thermal behaviors of the resulting polymers were examined.

• Preventive Nutrition and Food Science
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• v.17 no.2
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• pp.152-157
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• 2012

This study was performed to increase the availability of Sedum sarmentosum (Dolnamul) and to improve the nutraceutical value of rice cakes (sulgitteok). The contents of crude protein, mineral, dietary fiber, water holding capacity, and hardness significantly and directly increased with lyophilized sedum powder (SP). Pore ratio and expansion rate decreased in samples containing more than 10% SP compared to the control. In a sensory evaluation, a positive correlation was detected between overall acceptability and taste ($R^2$=0.99, p<0.01), and color ($R^2$=0.72, p<0.05). Total polyphenol contents of the SP-treated groups were significantly elevated, accompanied by an increase in radical scavenging ability estimated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Replacing 10% of the rice powder with SP efficiently improved the antioxidant and nutritional values of sulgitteok as well as its the sensory quality.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.5
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• pp.498-502
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• 1998

The present study was designed, fIrst to develop the new methodology to measure the bioluminescence activity easily in live developing bovine embryos by photoncounting, and secondly to compare the expression efficiency of four luciferase reporter genes in bovine embryos at four- to 16-cell stages. In experiment 1, equimolar pSVlacZ and pSVEluc were microinjected into the pronucleus of fertilized bovine oocytes. At 2 days after micro injection, bioluminescence activity of these embryos was measured by photoncounting with a luminometer for 1 min, and lacZ gene expression in the same embryos was assayed by X-gal staining. All the luciferase-positive oocytes showed some bacterial ${\beta}$-galactosidase activity irrespective of the intensity. In experiment 2, four firefly luciferase genes (pTKEluc, pTK6WEluc, pSVEluc and pMiwluc) were introduced by micro injection, and the injected embryos were cultured for the following 2 days. Detection of the luciferase gene expression was done by photoncounting at 5 to 55 min. Over the measurement period, the luciferase activity was almost constant irrespective of the transgenes microinjected. The luciferase activity and expression efficiency at 2 days after microinjection were not significantly affected by the difference in the microinjected transgenes. The present results demonstrated that the bioluminescence activity in live developing bovine embryos could be measured quickly by photoncounting.

• Macromolecular Research
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• v.8 no.3
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• pp.131-136
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• 2000

The synthesis of poly(2-ethynylpyridine) having glycidyl functionality was performed by the direct polymerization of 2-ethynylpyridine and epibromohydrin under mild reaction conditions without any initiator and catalysts. The polymerization proceeded well to give the resulting poly(2-ethynylpyridinium bromide) with a glycidyl functionality having relativity high molecular weight in high yields. The polymer structure was characterized by various instrumental methods to have the conjugated polymer backbone structure having glycidyl functionality. This ionic polymer was completely soluble in water, methanol, DMF, DMSO, and N,N-dimethylacetamide, but insoluble in THF, toluene, acetone, nitrobenzene, and n-hexane. This polymer system exhibited the UV-visible absorption around 300 and 520 nm and red photoluminescence spectrum around 725 nm.

• Macromolecular Research
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• v.14 no.5
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• pp.524-529
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• 2006

New, thermally robust, arylenevinylene conjugated polymers, including poly(9,9-dioctylfluorenyl-2,7-vinylene) [poly(FV)] and poly[2-(3'-dimethyldodecylsilylphenyl)-1,4-phenylenevinylene] [poly(m-SiPhPV)], were synthesized and used for the fabrication of efficient photovoltaic cells. Bulk heterojunction photovoltaic cells fabricated by blending one of the polymers, [poly(FV)], [poly(m-SiPhPV)], and poly(FV-co-m-SiPhPV), with the fullerene derivative [6,6]-phenyl-$C_{61}$-butyric acid methyl ester (PCBM) were found to have a power conversion efficiency of up to 0.038%..

• Microbiology and Biotechnology Letters
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• v.33 no.4
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• pp.241-247
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• 2005

A new lactococcal shuttle/expression vector for lactococci, pWgal13T, was constructed using a $\beta$-galactosi-dase gene (lacZ) from Lacfococcus lactis ssp. lactis ATCC 7962 as a screening marker. The pWgal 13T was introduced into Escherichia coli DH5a and L. lactis MG1363, and was easily detected by the formation of blue colonies on a medium containing X-gal without any false transformants. Also, the quantitatively lacZ activity of pWgal13T was measured in L. lactis ssp. cremoris MG1363, and was found to be four times higher than that of L. lactis ssp. lactis ATCC7962 grown on a medium containing glucose, which shows that the lacZ gene of pWgal13T can be used for the efficient screening of L. lactis on general media. The pWgal13T was equipped with a lactococcal replicon of pWV01 from L. lactis Wg2, the new promoter P13C from L. lactis ssp. cremoris LM0230, multiple cloning sites, and a terminator for the expression of a relevant gene. The vee-tor pWgal13T was used for the expression of the EGFP gene in E. coli and L. lactis. These results show that the lactococcal expression/shuttle vector constructed in the present study can be used for the production of foreign proteins in E. coli and L. lactis.

• Journal of Microbiology and Biotechnology
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• v.11 no.6
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• pp.915-921
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• 2001

Phytase improves the bioavailability of phytate phosphorus in plant foods to humans and animals, and reduces the phosphorus pollution of animal waste. In order to express a high level of fungal phytase in Saccharomyces cerevisiae, various expression vectors were constructed with different combinations of promoters, translation enhancers, signal peptides, and terminator. Three different promoters fused to the phytase gene (phyA) from Aspergillus niger were tested: a galactokinase (GAL1) promoter, glyceraldehyde-3-phosphate dehydrogenase (GPD) promoter, and yeast hybrid ADH2-GPD promoter consisting of alcohol dehydrogenase II (ADH2) and a GPD promoter. The signal peptides of phytase, glucose oxidase (GO), and rice amylase 1A(RAmy1A) were included. Plus, the translation enhancers of the ${\Omega}$ sequence and UTR70 from the tobacco mosaic virus (TMV) and spinach, respectively, were also tested. Among the recombinant vectors, pGphyA06 containing the GPD promoter, the ${\Omega}$ sequence, RAmy1A, and GAL7 terminator expressed the highest phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase activity in a culture filtrate, which was estimated at 20 IU/ml. An intracellular localization of the expressed phytase was also performed by inserting an endoplasmic reticulum (ER) retention signal, KDEL sequence, into the C-terminus of the phytase within the vector pHphyA-6. It appeared that the KDEL sequence directed most of the early expression of phytase into the intracellular compartment yet more than $60\%$ of the total phytase activity was still retained within the cell even after the prolonged (>3 days) incubation of the transformant. However, the intracellular enzyme activity of the transformant without a KDEL sequence was as high as that of the extracellular one, thereby strongly suggesting that the secretion of phytase in S. cerevisiae appeared to be the rate-limiting step for the expression of a large amount of extracellular recombinant phytase, when compared with other yeasts.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.80-89
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• 1996

The expression and secretion of human lactoferrin (hLf) in Sacclnromyces diastaticus were performed. 1. For the secretion of hLf in yeast, recombinant plasmid pYEGLf was constructed using promoter, secretion signal sequence of glucoamylase I gene (STA1) and transcriptional terminator of GAL7 gene. 2. Each correct recombinant plasmid was selected by mini-preparation of plasmid DNA from E coli transformant and restriction enzyme digestion analysis. The selected plasmids, pYEGLf, were transformed into S. diastaticus YIY345 as a expression host, respectively. 3. Western blot analysis using rabbit anti-hLf was carried out to identify expressed hLf. Positive signals were shown in culture supernatant of pYEGLf transformant. 4. About $100{\mu}g-1mg$ of concentrated culture supernatant of positive clone were loaded on paper disc and tested for the antimicrobial activity against E coli. However, no activity was observed. We concluded that this fact results from low concentration of hLf secreted from yeast, compared with the fact that MIC of hLf is as high as $3mg/m{\ell}$. Therefore, the purification of secreted hLf may be require to investigate the antimicrobial activity. From this study, the feasibility of low-cost production of sufficient quantities of human lactofferin for nutritional and therapeutical applications were suggested.

• Journal of the Earthquake Engineering Society of Korea
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• v.5 no.5
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• pp.73-83
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• 2001

The mass and stiffness of upper wall-lower frame system(mixed building structures) change sharply at transfer floor due to different structural system in upper and lower part. These mixed building structures generally show the stiffness, weight or geometric vertical irregularities. The purpose of this study is to investigate the response characteristics of these structures by push-over analysis and nonlinear time history analysis. For four types of analysed models, only the variation of upper wall stories was considered. The conclusions of this study are following; (1) In the push-over analysis, yielding hinges in beams and columns of lower frame occurred at the base shear of similar magnitude in all models. But as the number of stories of upper wall increases, yielding hinges at ends of coupling beams were observed in the small magnitude of base shear. (2) In the nonlinear time history analysis, yielding of lower frame occurred at beams with as small ground acceleration as 55gal, and in upper walls yielding was concentrated on coupling beams and shear walls near the transfer floor. (3) As the number of stories of upper walls decreases, the story stiffness of the lower frames decreased relatively and the occurrence of soft stories in the lower frame was observed.

• Applied Microscopy
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• v.35 no.4
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• pp.55-63
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• 2005

The characteristics of primary cultured rat brain microvessel endothelial cells (RBMECs) were studied using microscopy, immunohistochemistry and measuring of transendothelial electrical resistance (TER). The RBMECs formed a monolayer by $5{\sim}6$ days after plating and showed characteristics of whirling appearance. The TER increased until day 5 and decreased then. There was few immunoreaction with anti-GFAP, anti-GalC, anti-neurofilament 160/200 kD antibodies. So the contamination of astrocyte, oligodendrocyte, and neuron. could be ruled out.. Immunoreaction to vWF antigen was widespread througout the cytoplasm as Weibel-Palade granule. Immunoreaction to tight junction proteins, i.e. occludin, ZO-1, and ZO-2 was seen at cell contact. In summary, RBMECs isolated and cultured showed morphological, immunohistochemical and electrical characteristics of blood-brain barrier (BBB). The in vitro BBB model can be used in studying characteristics of in vivo BBB.