• Title/Summary/Keyword: Biological Agents

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Evaluation of Rapid Immunochromatographic Assay Kit for HBsAg-Screening Using Whole Blood

  • Shin, Hyeong-Soon;Heo, Tae-Ryeon
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.5 no.5
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    • pp.362-365
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    • 2000
  • A rapid immunochromatographic assay kit using whole blood to screen hepatitis B surface antigen was developed and evaluated by using sera from 240 patients. The reference diagnosis was based on the results obtained with GENEDIA Anti-HBs Rapid kit which is very similar to the above kit except for the use of serum. The test demonstrated a good correlation with the reference immunochromatographic assay kit, that is, the sensitivity and the specificity of the kit was 100%, respectively. The rapid test kit using whole blood should be more convenient and useful for the diagnosis of hepatitis B virus because the kit does not need machines and time to prepare serum. In addition, this kit is safe from inadvertent infection during sample treatment because the blood is sterilized with hydrogen peroxide, eliminates the procedure required to prepare serum and reduces the possibility of exposure to infectious agents.

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Thermally Induced Mesophase Development in Ethanesilica Films via Macromolecular Templating Approach

  • Cho, Whirang;Char, Kook-Heon;Kwon, Su-Yong
    • Macromolecular Research
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    • v.17 no.9
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    • pp.697-702
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    • 2009
  • Mesoporous ethanesilica thin film was prepared using PEO-PLGA-PEO triblock copolymers as structure-directing agents and (1,2-bis(triethoxysilyl) ethane BTESE; bridged organosilicates) as inorganic precursors via one-step sol-gel condensation of ethanesilica precursors. The mesostructure of ethanesilica films is critically dependent on the processing experimental parameters after the hydrolyzed silica sol mixture was spin-cast. This study examined the effects of the block copolymer template/organosilica precursor ratio in the casting solution and aging period before calcination of the mesostructure. It was further demonstrated that mesoscopic ordering of organosilicate thin films is induced by the rearrangement of block copolymer template/organosilica hybrid during thermal decomposition of the PEO-PLGA-PEO triblock copolymer. The mesoporous structure and morphology were characterized by SAXS, TEM and solid-state NMR measurement.

Isolation of 3-Galloylprocyanidin B3, a Glucosyltransferase Inhibitor from the Korean Green Tea Leaves

  • Cho, Young-Je
    • Journal of Applied Biological Chemistry
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    • v.43 no.4
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    • pp.273-276
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    • 2000
  • In the course of surveying the anti-plaque agents for dental caries prevention, the extract of Korean green tea leaves (KGTL) was tested for inhibitory activity against Streptococcus mutans adhering to glass surfaces in the presence of crude glucosyltransferase (GTase). The extracts of KGTL showed a positive inhibitory activity against GTase. The active compound was purified through Sephadex LH-20 and MCI gel CHP-20P columns. A positive reaction was shown in the anisaldehyde-$H_2SO_4$ test, which confirmed the condensed tannin. The inhibitory compound was identified as 3-galloylprocyanidin $B_3$ through IR, negative FAB-mass, and $^{1}H$-NMR spectroscopic analyses. Acetone extract and 3- galloylprocyanidin $B_3$ of KGTL showed inhibitory effect against GTase. The percent of inhibition was determinated to be 71.84% (P<0.01) with 10 mM 3-galloylprocyanidin B3. The 3-galloylprocyanidin $B_3$, which possessed a galloyl, showed a higher inhibitory activity against glucosyltransferase than monomeric (+)-catechin and procyanidine $B_3$ which had no galloyl group.

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Effects of Dehydrating Agents on the Physicochemical Properties of Dried Plum (Prunus salicina L.) Slices

  • Kim, Min-Sung;Kang, Ji-Hoon;Chung, Kyung-Sook;Won, Misun;Song, Kyung Bin
    • Journal of Applied Biological Chemistry
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    • v.56 no.1
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    • pp.19-22
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    • 2013
  • Plum (Prunus salicina L.) slices were dehydrated with red algae extract (RAE) at a concentration of 30% (w/w), and the dried samples were compared with maltodextrin (MD)-treated and hot-air dried samples in terms of physicochemical properties such as rehydration ratio, ascorbic acid, microstructure, and color. The rehydration ratios and colors of RAE-treated plum slices were better than those of MD-treated and hot-air dried samples. The ascorbic acid contents of RAE-treated samples were higher and their microstructures were finer than those of MD-treated or hot-air dried samples. These results suggest that plum slices can be dehydrated with RAE without loss of quality.

Polymerization of Vinyl Monomers Initiated by Thianthrene Cation Radical with Potential Biological Activity

  • Lee, Beomgi;Kim, Seongsim;Park, Jaeyoung;Cheong, Hyeonsook;Noh, Ji Eun;Woo, Hee-Gweon
    • Journal of Integrative Natural Science
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    • v.5 no.2
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    • pp.127-130
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    • 2012
  • Polymerization of vinyl monomers is promoted by thianthrene cation radical as a part of our research concerning the reactions of various agents with readily isolable, yet highly reactive species and elucidate the biological activity. Thianthrene cation radical initiated the homopolymerization and copolymerization of styrene and ethyl vinyl ether. The polymerization yields decreased as the concentration of phenylacetylene or diphenylethylene increased. Such polymereization by cationic thianthrene radical could provide some clues for the reaction in living animals. Comments on possible polymerization mechanisms were suggested.

Gd-complexes of DTPA-bis(amide) Conjugates of Phosphonated Tranexamic Esters as MRI Contrast Agents

  • Patel, Mehul A.;Kim, Hee-Kyung;Lee, Gang-Ho;Chang, Yong-Min;Kim, Tae-Jeong
    • Bulletin of the Korean Chemical Society
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    • v.32 no.3
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    • pp.1022-1026
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    • 2011
  • The syntheses of DTPA-bis(amide) conjugates of phosphonated cyclohexane moieties (5a-d) and their Gd(III) complexes of the type $[Gd(L)(H_2O)]{\cdot}nH_2O$ (6a-d; L = 5a-d) are described. All new compounds have been characterized by microanalysis and spectroscopic techniques. High $r_1$ relaxivities of aqueous solutions of 6a-d are observed to be in the range of $10.7-18.3\;mM^{-1}sec^{-1}$, which compare much better than that of $Omniscan^{(R)}$ ($r_1=3.90\;mM^{-1}sec^{-1}$).

Paclitaxel Suppress Dedifferentiation via Mitogen-activated Protein Kinase Pathway in Rabbit Articular Chondrocyte

  • Im, Jeong-Hee;Kim, Song-Ja
    • Biomedical Science Letters
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    • v.15 no.1
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    • pp.67-72
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    • 2009
  • Microtubule-interfering agents (MIAs), including paclitaxel, have been attributed in part to interference with microtubule assembly, impairment of mitosis, and changes in cytoskeleton. But the signaling mechanisms that link microtubule disarray to destructive or protective cellular responses are poorly understood. This study investigated the effect of paclitaxel on differentiation such as type II collagen expression and sulfated proteoglycan accumulation in rabbit articular chondrocytes. Paclitaxel caused differentiated chondrocyte phenotype as demonstrated by increment of type II collagen expression and proteoglycan synthesis Paclitaxel treatment stimulated activation of ERK-1/2 and p38 kinase. Inhibition of ERK-1/2 with PD98059 enhanced paclitaxel-induced differentiation, whereas inhibition of p38 kinase with SB203580 suppressed paclitaxel-induced differentiation. Our findings suggest that ERK-1/2 and p38 kinase oppositely regulate paclitaxel-induced differentiation in chondrocytes.

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Schizophrenia : Changing Concepts and the Development of Novel Antipsychotics

  • Remington, Gary
    • Korean Journal of Biological Psychiatry
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    • v.3 no.1
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    • pp.22-29
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    • 1996
  • The introduction of chlorpromazine in the 1950's revolutionized the treatment of schizophrenia and ultimately led to the development of selective $D_2$ antagonists such as haloperidol, a goal in keeping with the prevalent theories at that time. However, limitations in the efficacy of these agents, a growing awareness of their side effects, and theoretical shifts in our understanding of schizophrenia have encouraged ongoing efforts to develop better 'atypical' antipsychotics. Clozapine, and subsequently risperidone, represent examples of these novel compounds, both of which incorporate shared serotonin-dopamine antagonism(SDA). The next years will be dominated by further development of SDA compounds, although a number of other lines of investigation are also being pursued.

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Cytotoxic Activity of Medicinal Plant Extracts against Human Tumor Cell Lines

  • Jeong, In-Hong;Lee, Jeong-Ock;Kim, Choul-Soo;Kim, Soo-Un;Ahn, Young-Joon
    • Journal of Applied Biological Chemistry
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    • v.43 no.1
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    • pp.59-61
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    • 2000
  • The cytotoxic activities of the methanol extracts of 44 plant species in 31 families against five human solid A549 (lung), SK-OV-2 (ovarian), SK-MEL-2 (melanoma), XF-498 (central nervous system), and HCT-15 (colon) tumor cell lines were examined using the sulforhodamine B (SRB) assay. Responses varied with both cell line and plant species used. Potent cytotoxic activities ($ED_{50}$, <$40{\mu}g/ml$) against all model tumor cell lines were produced from the extracts of Rhus chinensis gall (Galla rhois), Betula platyphylla var. japonica bark, Inula helenium root, Cinnamomum cassia bark, Cinnamomum sieboldii root bark, Lysimachia davurica whole plant, and Evodia rutaecarpa fruit. These plants may be useful for developing new types of naturally occurring anti-tumor agents.

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Anti-oxidant activity of avicularin and isovitexin from Lespedeza cuneata

  • Lee, Ju Sung;Lee, Ah Young;Quilantang, Norman G.;Geraldino, Paul John L.;Cho, Eun Ju;Lee, Sanghyun
    • Journal of Applied Biological Chemistry
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    • v.62 no.2
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    • pp.143-147
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    • 2019
  • This study evaluated the anti-oxidant activity of avicularin and isovitexin from Lespedeza cuneata using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl (OH) scavenging assays. The results showed that among the four fractions, the highest OH radical scavenging activity was exhibited by the n-butanol fraction. The DPPH radical scavenging activities of avicularin and isovitexin were higher than 50% at a concentration of $100{\mu}g/mL$. Moreover, one hundred micrograms per liter of avicularin and isovitexin exhibited effective anti-oxidant activity, with the OH radical scavenging rates being 87.54 and 91.48%, respectively. These results suggest that Lespedeza cuneata would be useful anti-oxidant agents from natural sources.