• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.202-210
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• 2005

In this study, the fly ash was employed as a possible alternative to the bentonite for its high sorption capacity against cationic heavy metal. To consider the constituents of barrier possibly used, the specimens were mixed with different material contents (fly ash : weathered soil : bentonite), then sorption test was performed. Also the specimens were molded on the wet side of optimum moisture contents like mixing ratio of sorption test and their hydraulic conductivities were measured in flexible-wall permeameters. And to confirm the effect of dissolved cations, the hydraulic conductivity tests were repeated by converting the permeant liquids from water to $Cd^{2+}$ solution. Finally, the Cd-concentration at the effluent was analyzed for 500hrs to compare the effectiveness of each specimen in contaminant retardation. Test results showed that the more the ratio of fly ash increase, the more Kd value increase, and the hydraulic conductivity of weathered soil/bentonite (95:5) mixture was the lowest $(2.9*10^{-8}cm/sec)$, and specimens made of fly ash and fly ash/weathered soil mixtures showed similar hydraulic conductivity. Although the permeant liquid was changed from water to $Cd^{2+}$ solution, the hydraulic conductivity of all specimens except for weathered soil maintained similarly like before. Consequently, the initial breakthrough point of Cd in weathered soil specimen was observed at about 5hrs after the test started while that of fly ash specimens was not observed during the whole test period of 500hrs. The results implied that fly ash had a sufficient retardation capacity against contaminant transport possibly by its high sorption capacity although it showed little effect on the reduction of hydraulic conductivity. Based on the test results, it could be concluded that the fly ash can be possibly used as a suitable barrier material in containment system to attenuate the contaminant transport for its high retardation capacity and for the low cost.

• Korean Journal of Plant Tissue Culture
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• v.25 no.5
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• pp.341-346
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• 1998

In this paper we describe the cloning and expression of the genes encoding the flavonoid-biosynthetic enzyme dihydroflavonol 4-reductase (DFR) in Matthiola incana R. Br. A heterologous cDNA probe from Zea mays was used to isolate full-size DFR cDNA clone from a corolla-specific cDNA library. Comparison of the coding region of this DFR cDNA sequence including the sequences of Zea mays, Anthirrinum majus, Petunia hybrida, Callistephus chinensis, Dianthus caryophyllus and Rosa hybrida reveals a identity higher than 61% at the nucleotide level. The DFR transcript is G/C rich in monocotyledonous plants show a strong codon bias preferring codons with a G or C in the third position. The function of this nucleotide sequences were verified by comparison with amino acid sequences of the amino-terminus and tryptic peptides from purified plant enzyme, by northern blotting with mRNA from wild type and mutant plants and by in vitro expression yielding an enzymatically active reductase. Genomic southern blot analysis showed the presence of one gene for DFR in Matthiola incana. Northern blot analysis of the DFR wild type and mutant lines showed that the lack of DFR activity in the stable acyanic mutant k17b is clearly by a transcriptional block of the DFR gene.

• Korean Journal of Microbiology
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• v.40 no.4
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• pp.269-274
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• 2004

Serratia proteamaculans isolated from the midgut of a spider formed big halos around the bacterial colonies, indicating that the bacterial strain produces an extracellular protease. Activity staining of the extracellular pro­tein fractions using zymogram also demonstrated that the major protein with an estimated molecular mass of 52 kDa contained a high proteolytic activity. The protease was purified to near electrophoretic homogeneity from the culture supernatant after filtration and ion exchange and size exclusion chromatography. The purified enzyme had a relatively high proteolytic activity between pH 6.0 and 10.0 and at broad temperature range. The proteolytic activity of the enzyme was not inhibited by phenylmethylsulfonyl fluoride but strongly inhibited by 1, 10-phenanthroline and EDTA. The activity also was dependent on the presence of $Ca^{++}\;and\;Zn^{++}$ ions. These observations indicate that the enzyme is a metalloprotease.

• Korean Journal of Environmental Agriculture
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• v.20 no.3
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• pp.162-168
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• 2001

This study was conducted to evaluate the degradation, adsorption and desorption and leaching of acetamiprid in soils. The half-life of acetamiprid in field condition was $1.7{\sim}3.3$ days in Bokhyun soil and, in case of laboratory condition, 15.5 days. Adsorption of acetamiprid was equilibrated in 12 hours incubation. In adsorption experiment using modified soils, such as oxidized soil, oxidized soil added humic acid, fulvic acid, kaolinite or montmorillinite, adsorption rate of acetamiprid was the highest in the oxidized soil added fulvic acid. The desorption rate was the lowest in the oxidized soil added fulvic acid. The adsorption and desorption results should be suggested that acetamiprid could be strongly adsorbed with soil humic materials, especially fulvic acid. When the mobility of acetamiprid in soil was calculated according to GUS (Groundwater Ubiquity Score) equation, it was prove to non-leacher, and it was confirmed in the leaching experiment with soil column. Most of acetamiprid was remained in the upper 30 cm of the soil column after eluting with water and it was not even detected in leachate.

• Journal of Plant Biology
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• v.35 no.3
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• pp.247-252
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• 1992

The effect of iso-butanol on the electron transport rate of PS I and PS II was investigated in isolated spinach chloroplasts. In photosystem I, the rate of electron transport increased in the presence of 1 to 4% of isobutanol but decreased in 5 to 9% of iso-butanol. But in photosystem II, the rate of electron transport decreased when treated with 0.2 to 1% of iso-butanol. The inhibitory effect of isomers of butanol on PS II electron transport rate increased in the order of 2-butanol, tert-butanol, iso-butanol and I-butanol. This means that PS II activity was affected according to the arrangement of carbon atoms in butanol. The inhibitory effect of iso-butanol reduced when DPC was added in the solution. This means that iso-butanol affects PS II reduction side of thylakoid membrane primarily. The inhibitory effect of iso-butanol was reduced when $Mn^{2+},\;C^{2+}$ or BSA were added in the solution. PS II activity was restored when 1% iso-butanol treated chloroplast solution was diluted to twentyfold or when $Mn^{2+},\;C^{2+}$ or BSA was added to the diluted solution. However, the SDS-PAGE banding pattern of thylakoid membrane proteins was similar even in 2% iso-butanol treated chloroplasts and the control ones. Only in 5% iso-butanol treated chloroplasts these bands were very weak. These observations suggest that low concentrations of iso-butanol releases manganese and calcium ions from chloroplasts and inhibits the electron transport system. This inhibitory effect can be reversible in low concenterations but in high concentrations the inhibitory effect of iso-butanol become irreversible.rsible.

• Journal of the Korean Chemical Society
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• v.30 no.1
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• pp.51-56
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• 1986

Polarographic behavior of cadmium(II) and copper (II) complexes of 1,5-diphenylcarbohydrazide in dimethylsulfoxide have been investigated by the DC polarography. The reduction processes are estimated as follows; Cd(II)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.12V)}$${\to}$Cd(I)${\cdot}$DPH Complex. Cd(I)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.74V)}$${\to}$Cd(Hg) + nDPH. Cu(II)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.44V)}$${\to}$Cu(I)${\cdot}$DPH Complex. Cu(I)${\cdot}$DPH Complex$\frac{e^-}{(E_{\frac{1}{2}}=-0.84V)}$${\to}$Cu(Hg) + nDPH. The limiting currents of all reduction wave are irreversible. The number of ligand and the dissociation constant for Cu(I)${\cdot}$1.5-diphenylcarbohydrazide complex were found to be 2 and 5.12 ${\times}10^{-8}$, respectively. All reduction waves of complexes are irreversible. Based on the experimental results, the polarographic reductions of complexes in dimethylsulfoxide solution occurred in two one-electron steps.

• Journal of Life Science
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• v.25 no.6
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• pp.631-637
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• 2015

Streptavidin, a protein produced by Streptomyces avidinii, strongly binds up to four molecules of vitamin H, d-biotin exhibiting the dissociation constant of about 10⁻¹⁵ M. This strong binding affinity has been applied for detection and characterization of numerous biological molecules suggesting expression and purification of functional streptavidin should be very useful for the application of this streptavidin-biotin interaction. To express a soluble streptavidin in Escherichia coli, We synthesized streptavidin genes and cloned into pET-22b plasmid, which uses T7 RNA polymerase/T7 promoter expression systems containing pelB leader for secretion into periplasmic space and six polyhistidine tags at C-terminus for purification of expressed proteins. Although streptavidin is toxic to Escherichia coli due to strong biotin binding property, streptavidin was expressed very sufficiently in a range of 10-20 mg/ml. In SDS-PAGE, the size of purified protein was shown as 17 kDa in denatured condition (boiling) and 68 kDa in native condition (without boiling) suggesting tetramerization of monomeric subunit by non-covalent association. Further analysis by size-exclusion chromatography supported streptavidin’s tetrameric structure as well. In addition, soluble streptavidin detected biotinylated proteins in westernblot indicating its functional activity to biotin. Taken these results together, it concluded that our simple expression system was able to show high yield, homotetrameric formation and biotin binding activity analogous to natural streptavidin.

• Journal of Life Science
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• v.22 no.11
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• pp.1500-1506
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• 2012

Transforming growth factor (TGF)-${\beta}$-dependent apoptosis is important in the elimination of damaged or abnormal cells from normal tissues, especially in liver, in vivo. To investigate which gene expressions are critical for TGF-${\beta}$-induced apoptosis in hepatocytes, gene expression profiling experiments were performed with TGF-${\beta}$-treated and non-treated mouse hepatocytes AML12 cells. Findings showed that serum and glucocorticoid-inducible protein kinase1 (SGK1) expression is markedly downregulated during TGF-${\beta}$-induced apoptosis. Findings confirmed that expression of SGK1 protein, as well as mRNA, is also markedly decreased with TGF-${\beta}$ treatment. Infection of adenoviral vector encoding constitutively active SGK1 (CA-SGK1), but not kinase dead SGK1 (KD-SGK1), attenuated TGF-${\beta}$-induced apoptosis. All of these results suggest that downregulation of SGK1 expression is critical for TGF-${\beta}$-induced apoptosis in AML12 cells.

• Clinical and Experimental Pediatrics
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• v.59 no.4
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• pp.174-177
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• 2016

Purpose: There are no specific tests for diagnosing Kawasaki disease (KD). Additional diagnostic criteria are needed to prevent the delayed diagnosis of incomplete Kawasaki disease (IKD). This study compared the frequency of coronary artery lesions (CALs) in IKD patients with and without anterior uveitis (AU) and elucidated whether the finding of AU supported the diagnosis of IKD. Methods: This study enrolled patients diagnosed with IKD at The Catholic University of Korea, Uijeongbu St. Mary's Hospital from January 2010 to December 2014. The patients were divided into 2 groups: group 1 included patients with IKD having AU; and group 2 included patients with IKD without AU. We analyzed the demographic and clinical data (age, gender, duration of fever, and the number of diagnostic criteria), laboratory results, and echocardiographic findings. Results: Of 111 patients with IKD, 41 had uveitis (36.98%, group 1) and 70 did not (63.02%, group 2). Patients in group 1 had received a diagnosis and treatment earlier, and had fewer CALs (3 of 41, 1.7%) than those in group 2 (20 of 70, 28.5%) (P=0.008). All 3 patients with CALs in group 1 had coronary dilatation, while patients with CALs in group 2 had CALs ranging from coronary dilatation to giant aneurysm. Conclusion: The diagnosis of IKD is challenging but can be supported by the presence of features such as AU. Group 1 had a lower risk of coronary artery disease than group 2. Therefore, the presence of AU is helpful in the early diagnosis and treatment of IKD and can be used as an additional diagnostic tool.

• Archives of Pharmacal Research
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• v.23 no.4
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• pp.353-359
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• 2000

${\alpha}_2$-Adrenoceptor antagonists, which can enhance synaptic norepinephrine levels by blocking feedback inhibition processes, are potentially useful in the treatment of disease states such. as depression, memory impairment, impotence and sexual dysfunction. (10bS)-1,2,3,5,6,10b-Hexahydropyrrolo[2,1-a]isoquinoline oxalate (YSL-3S) was evaluated in several in vitro biological tests to establish its pharmacological profile of activities as an ${\alpha}_2$-adrenoceptor antagonist. Saturation binding assay revealed that$^{3}[H]$rauwolscine bound to the $\alpha$$_2$-adrenoceptors with a Kd value of 6.3$\pm$0.5 nM and a Bmax value of 25l$\pm$39 fmol/mg protein in rat cortical synaptic membranes. Competitive binding assay showed that YSL-3S inhibited the binding of$^3[H]$rauwolscine (1 nM) in a concentration-dependent manner with a Ki value of 98.2$\pm$12.1 nM while it did not inhibit the binding of [$^3$H]cytisine (1.25 nM) to neuronal nicotinic cholinergic receptors. The Ki values of yohimbine, clonidine and norepinephrine for $^3[H]$rauwolscine binding were 15.8$\pm$1.0, 40.1$\pm$5.9 and 40.0$\pm$11.5 nM, respectively. In addition, the binding affinity of YSL-3S for ${\alpha}_2$-adrenoceptors was higher than that of its antipode and the racemic mixture. The functional activity of YSL-3S at the presynaptic ${\alpha}_2$-adrenoceptors was assessed using the prostatic portion of the rat vas deferens. Clonidine inhibited field-stimulated contractions of the vas deference in a dose-dependent manner. The presence of YSL-3S or yohimbine caused a parallel, rightward the dose-response curve of clonidine in a dose-dependent manner, indicating an antagonistic action at the presynaptic ${\alpha}_2$-adrenoceptors. The $pA_2$values of yohimbine and YSL-3S were 7.66$\pm$0.13 and 6.64$\pm$0.18, respectively. The results indicate that YSL-3S acts as a competitive antagonist at presynaptic ${\alpha}_2$ -adrenoceptors with a potency approximately ten times lower than yohimbine, but is devoid of binding affinity for neuronal nicotinic cholinergic receptors.