• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1613-1619
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• 2011

A hybrid thermosetting maleimido epoxy compound 4-(N-maleimidophenyl) glycidylether (N-MPGE) containing Co(II), Ni(II) and Cu(II) ions was prepared by curing N-MPGE and tetradentate Schiff base Co(II), Ni(II) and Cu(II) complexes. The curing polymerization reaction of N-MPGE with metal complexes as curing agents was studied. The cured samples were studied for thermal stability, chemical (acid/alkali/solvent) and water absorption resistance and homogeneity of the cured systems. The tetradentate Schiff base, 3-[(Z)-2-piperazin-1-yl-ethylimino]-1,3-dihydro indol-2-one was synthesized by the condensation of Isatin (Indole-2, 3-dione) with 1-(2-aminoethyl)piperazine (AEP). Its complexes with Co(II), Ni(II) and Cu(II) have been synthesized and characterized by microanalysis, conductivity, Uv-Visible, FT-IR, TGA and magnetic susceptibility measurements. The spectral data revealed that the ligand acts as a neutral tetradentate Schiff base and coordinating through the azomethine nitrogen, two piperazine nitrogen atoms and carbonyl oxygen.

• Fisheries and Aquatic Sciences
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• 제15권2호
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• pp.145-150
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• 2012

An improved strain of the red seaweed Porphyra suborbiculata containing an increased amount of the essential amino acid L-lysine was obtained through mutation and analog enrichment. Mutagenesis using a 10% lethal dose of ultraviolet irradiation and an enrichment culture with the L-lysine analog aminoethyl-L-cysteine (AEC) was repeated to select the most productive strain using monospores of P. suborbiculata. The concentrations of AEC required to produce 50 and 100% inhibition of survival were 60 and 115 mM in the parent strain, and 72 and 135 mM in the selected AEC-resistant strain, respectively. The AEC-resistant strain, L130, produced 1.74-fold more lysine compared to its parent strain. Thus, mutagenesis with analog enrichment shows promise for selecting seaweed strains that can overproduce this essential amino acid.

• Journal of Plant Biotechnology
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• 제6권4호
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• pp.259-264
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• 2004

The present study describes the ameliorating effect of $Ca^{++}\;on\;Cd^{++}$ toxicity on the germination, early growth of mungbean seedlings, nitrogen assimilation enzyme. s-nitrate reductase (NR), nitrite reductase (NIR), anti-oxidant enzymes (POD, CAT and SOD) and on the accumulation of hydrogen peroxide and sulphydryls. $Cd^{++}$ inhibited seed germination and root and shoot length of seedlings. While NR activity was down- regulated, the activities of NIR, POD and SOD were up- regulated with $Cd^{++}$ treatment. $Cd^{++}$ treatment also increased the accumulation of sulphydryls and peroxides, which is reflective of increased thiol rich proteins and oxidative stress. $Ca^{++}$ reversed the toxic effects of $Cd^{++}$ on germination and on early growth of seedlings as well as on the enzyme activities, which were in turn differentially inhibited with a combined treatment with calcium specific chelator EGTA. The results indicate that the external application of $Ca^{++}$ may increase the tolerance capacity of plants to environmental pollutants by both up and down regulating metabolic activities. Abbreviations: $Cd^{++}= cadmium,\;Ca^{++} = calcium$, NR= nitrate reductase, NIR=nitrite reductase, POD = peroxidse, SOD= superoxide dismutase, CAT= catalase, EGTA= ethylene glycol-bis( $\beta-aminoethyl ether$)-N,N,N,N-tetraacetic acid.

• 약학회지
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• 제41권2호
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• pp.187-194
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• 1997

For the development of antifungal agents, modification of naftifine which exhibits significant antimycotic activity was performed by replacing the naphthalene ring of it to hete ro cyclic rings such as morpholine. benzothiazole, piperidine and pyridine derivatives. The synthesized compounds were tested in vitro antifungal activity against five different fungi with naftifine as a comparative antimycotic molecule. From the biological evaluation two compounds, (E)-N-(3-phenyl-2-propenyl)-N-(4-piperidinylmethyl)amine(3d) and (E)-N-(3-phenyl-2-propenyl)-N-(3-pyridylmethyl)amine(3f) showed relatively noticeable activity(MIC=50${\mu}g$/ml). On the other hand, the other compounds had no activity.

• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.206-212
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• 1995

A strain BL-29, which produces a extracellular lytic enzyme on E. coli was isolated from the soil. The strain was identified as belonging to the genus Bacillus sp. The lytic enzyme was purified to homogeneity by ion exchange chromatography and gel filtration. Specific activity of the purified enzyme was 28, 850 U/mg protein and yield of the enzyme was 5$%$. The purified enzyme showed a single band on SDS-PAGE and its molecular weight was estimated to be 31, 000 by SDS-polyacrylamide gel electrophoresis and gel filtration column chromatography. The optimum temperature and pH were $55^{\circ}C$ and pH 10.0, respectively. The enzyme was stable at $45^{\circ}C$ but enzyme activity was reduced by up to 50$%$ when the temperature was raised to $55^{\circ}C$ for 15 min. Stable range of pH was from 5.0 to 11.0. but Enzyme activity was inhibited by lead-acetate, mercuric chloride, ethylene glycol-bis-[$\beta$-aminoethyl ether]-N, N, $N^1, $N^1$-tetraacetic acid (EGTA), and ethylenediamine tetraacetic acid (EDTA), but not affected considerably by treatment with other chemical reagents.

• 한국응용과학기술학회지
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• 제12권2호
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• pp.51-58
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• 1995

To prepare a durable softening water repellent, quaternized octadecyl methacrylate-2-diethyl-aminoethyl methacrylate as a mother resin and quaternized 1, 3-dioctadecyl-2, 7-dioxy-6, 8-di(2-hydroxyethyl)-1, 3, 6, 8-tetraazacyclodecane which increase the softening effect and the hydrostatic pressure blended with waxes and their emulsifier in various proportions to give water repellent PADWC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyestercotton(P/C) blended fabrics treated with PADWC only or addition of textile finishing resin, the physical properties were increased. There was no significant lowering effect in water repellency when PADWC was treated the antistatic agent by the one-bath method, and the effect of water repellency by the adding the catalyst was studied. PADWC was confirmed as durable water repellent with the results of making little difference of water repellency as ${\pm}5$ point after and before washing.

• 분석과학
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• 제8권4호
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• pp.449-456
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• 1995

Novel macrocyclic ligands modified with pendant arms, N, N', N'', N''', N'''', N'''''-hexakis(2-aminoethyl)-1, 4, 7, 10, 13, 16-hexaazacyclootadecane [$L_3$, Fig.1] and 1, 4, 7-tris(3-(o-hydroxyphenyl)propyl)-1, 4, 7-triazacyclononane [$L_4$, Fig.1] have been synthesized, and the protonation of $L_3$ and $L_4$ and stability constants of $L_3$ with bivalent transition metal ions and rare earth metal ions were determined by a potentiometry. The obtained results show that the complex formation of $L_3$ depends on the metal ligand ratios, and the stability of the metal complexes does not depend on the sizes of the metal ions, but on the nature of the metal ions. The structures of the rare earth complexes for $L_4$ were characterized by an X-ray absorption spectrometry(XAFS).

• Restorative Dentistry and Endodontics
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• 제22권2호
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• pp.782-791
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• 1997

Glial fibrillary acidic protein(GFAP) are a group of intermediate filaments that are distributed in the cytoplasm of many type of glial cells. The purpose of this study was to determine change of GFAP immunoreactivity(GFAP-IR) in rat trigeminal ganglion satellite cells in response to pulp exposure. The immunohistochemistry was carried out using the avidinbiotin-peroxidase complex(ABC) method and subsequently stained with AEC(3-aminoethyl-9-carbasol). 1. Contol group; Central root astrocytes had strong GFAP-IR, but ganglion satellite cells occasionlly had GFAP-IR. This reaction patterns of ganglion satellite cells was not concenturated in any specific region of trigeminal ganglion. 2. Three day pulp exposure group; There was a highly GFAP-IR in satellite cells of trigeminal ganglion in maxillary region. GFAP-IR in neighboring mandibular and ophthalmic regions was less intense compared to maxillary region. 3. Seven day pulp exposure group; In this group, GFAP-IR that was increased compared to control group was seen in the maxillary region. But GFAP-IR was less intense compared to three day pulp exposure group. These results suggest that GFAP in satellite cell increase in specific region of trigeminal ganglion after pulp exposure and offer useful tool in trigeminal pain research.

• Bulletin of the Korean Chemical Society
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• 제29권7호
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• pp.1349-1352
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• 2008

We report a novel patterning method for a homo-polymeric poly(3-hexylthiophene) (P3HT) nanofilm particularly capable of strong adhesion to a $SiO_2$ surface. An oxidized silicon wafer substrate was micro-contact printed with n-octadecyltrichlorosilane (OTS) monolayer, and subsequently its negative pattern was selfassembled with three different amino-functionalized alkylsilanes, (3-aminopropyl)trimethoxysilane (APS), N- (2-aminoethyl)-3-aminopropyltrimethoxy silane (EDAS), and (3-trimethoxysilylpropyl) diethylenetriamine (DETAS). Then, P3HT nanofilms were selectively grown on the aminosilane pre-patterned areas via the vapor phase polymerization method. To evaluate the adhesion, patterning, and the film itself, the PEDOT nanofilms and SAMs were investigated with a $Scotch^{(R)}$ tape test, contact angle analyzer, ATR-FT-IR, and optical and atomic force microscopes. The evaluation showed that the newly developed all bottom-up process can offer a simple and inexpensive patterning method for P3HT nanofilms robustly adhered to an oxidized Si wafer surface by the mediation of $FeCl_3$ and amino-functionalized alkylsilane SAMs.

• Journal of Applied Biological Chemistry
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• 제43권3호
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• pp.156-160
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• 2000

The possible mechanism of the DNA strand breaking activity of the hot-water extract of Fructus Chaenomelis (dried fruit of Chaenomeles sinensis) in a closed circular duplex replica form DNA (RFI DNA) was studied through agarose gel electrophresis under various conditions. Induction of DNA strand scission by the hot-water extract of C. sinensis occurred in dose and time-dependent manners. $Cu^{2+}$ was indispensable for the induction of DNA strand breakage. Exogeneous chelating agents inhibited the DNA breaking activity, conforming the catalytic action of $Cu^{2+}$ on generation of free radicals responsible for oxidative damage. Antioxidant enzymes and some radical scavengers were used to investigate the major radical species triggering the DNA strand scission, demonstrating that a highest inhibitory activity was found in the presence of catalase, while less in the presence of tiron (a scavenger for superoxide radical), 2-aminoethyl-isothiuroniumbromide-HBr, cysteamine (scavengers for hydroxyl radical), and 1,4-diazabicyclo [2,2,2] octane (a scavenger for singlet oxygen) in decreasing order. The findings implied that oxygen radical species generated in presence of transition divalent cation during the oxidation of some compounds contained in the hot-water extract of C. sinensis is mainly responsible for inducing genotoxicity.