• Title/Summary/Keyword: Phthalic acid

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Rapid Simultaneous Determination of Anions in Mineral Water by Single Column Ion Chromatography (단일 컬럼이온크로마토그래피에 의한 광천수중 음이온의 신속한 동시정량)

  • Kim, Jong Hun;Choi, Yong Wook;Chung, Taek Kyun
    • Journal of the Korean Chemical Society
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    • v.39 no.12
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    • pp.910-917
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    • 1995
  • Analytical conditions for single column ion chromatographic determination of five anions such as F-, Cl-, NO2-, NO3-, and SO42- were optimized with respect to analysis time and separation efficiency. At the optimum condition of 2.0 mM phthalic acid at pH 4.5, five anions were effectively separated in 10 minutes so that analysis time could be reduced by 40% compared to other recommended conditions. Under this condition all the calibration curves of five anions were linear with a correlation coefficient > 0.999. Analytical results for nine commercial bottled waters were presented.

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Bee Venom Within Liposomes Synergistically Inhibit Atopic Dermatitis in Mice

  • Kim, Joan;Song, Ho Sueb
    • Journal of Acupuncture Research
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    • v.39 no.1
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    • pp.40-48
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    • 2022
  • Background: This study was performed to determine the effects of liposome-encapsulated bee venom (BV) treatment of inflammatory factors in atopic dermatitis (AD) compared with BV treatment. Methods: AD was induced by phthalic anhydride in mice and the effects of BV liposomes were measured. Using Leica Application Suite, thickened epidermis and dermis were measured after BV liposome treatment (0.05 and 0.1 ㎍/mL). The number of stained mast cells and the concentration of immunoglobulin (Ig)E were measured. Serum IgE concentration was analyzed using an enzyme-linked immunosorbent assay. The serum concentrations of interleukin (IL)-1, IL-4, and IL-6 inflammatory cytokines were measured. The levels of messenger ribonucleic acid expression of proinflammatory cytokines and chemokines were measured using reverse transcription polymerase chain reaction. Inhibition of mitogen-activated protein kinase activation, was analyzed on western blot. To measure the transcriptional activity (NF-κB inhibition by BV liposomes), western blots (p65, p-IκB, p50, and IκB) were also performed. Results: The weight of lymph nodes, serum IgE concentrations, morphological changes in the skins from the backs of the mice, and mast cell numbers in inflamed tissues were noticeably lower in the BV liposome treatment group compared with the BV treatment group. The concentrations of pro-inflammatory cytokines (IL-1, IL-4, IL-6) and chemokines (TSLP, CCL22) were also reduced. Activation of mitogen-activated protein kinase (p-ERK and p-p38), and transcriptional activity (p65, p-IκB, p50, and IκB) was strongly suppressed in the BV liposome group. Conclusion: BV liposomes may have a better therapeutic effect than BV for the treatment of AD.

Isolation and Characterization of Cathepsin B inhilbitor Produced by Streptomyces luteogriseus KT-10 (Streptomyces luteogriseus KT-10 이 생산하는 Cathepsin B 저해물질의 분리 및 특성)

  • 한길환;김상달
    • Microbiology and Biotechnology Letters
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    • v.29 no.2
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    • pp.84-89
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    • 2001
  • Isolation and Characterization of Cathepsin B inhibitor Produced by Streptomyces luteogriseus KT-IO. Han, Kil~Hwan and Sang~Dal Kim*. Department of Applied Microbiology, Yeungnam Universit}/t Kyongsan 712749, Korea - The cathepsin B inhibitor produced by Streptomyces luteogriseus KT-IO was very stable in heat, acidic and alkaline conditions. The cathepsin B inhibitor was isolated from the extracted fraction of culture broth with butanol, methanol and chloroform subsequently, the inhibitor was purified with following several column chromatography sLlch as DEAE-Sephadex A-25, Sephadex G-15, silica gel 60, Sephadex LH-20, and preparative HPLC. The cathepsin B inhibitor showed positively to detective reaction of ninhydrine, 5% H2S04, iodine, but negatively to the reaction of Ehrlich's reagent, DNS, aniline. The molecular formular of cathepsin B inhibitor was elucidated by JR, lH and 13C-NMR, FAB mass and elemental analyzer. Consequently, it was identified as C4HlI04N6. The cathepsin B inhibitor had the mode of competitive inhibition with the reaction of cathepsin B.

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Determination of Free 4-hydroxyproline with Dansylchloride by HPLC in Human Urine (소변 중 4-hydroxyproline 분석에 관한 연구)

  • Lee, Keou-Weon;Cho, Young-Bong;Lee, Kyung-Jong
    • Journal of Preventive Medicine and Public Health
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    • v.35 no.4
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    • pp.282-286
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    • 2002
  • Objectives : The level of 4-hydroxyproline (4-Hyp) in human urine was measured using high performance liquid chromatography (HPLC) with a fluorescence detector. This method is useful for medical examinations and investigating the radicals induced by physical, chemical, mental stresses. This method is superior to many published several methods in terms of its low cost and ability to analyze many samples. Methods : The urine from workers in a tire manufacturing company (22 male pre- and post-shift workers) and 18 office-workers as controls were analyzed. Data concerning age, the cumulative drinking amount and the cumulative smoking amount was collected with a questionnaire. The optimum applied amount of dansyl-Cl, the optimum reaction temperature and time, the recoveries and the optimum pH of the eluent and buffer were determined.4-Hyp from human urine was derivatized with dansyl-Cl (dimethylamino-naphthalene-1-sulfonyl chloride) after removing the a-amino acid by a treatment with phthalic dicarboxaldehyde (OPA) and cleaned with Bond Elut C18 column. The 4-Hyp derivatives were separated on a reversed phase column by gradient elution with a phosphate buffer (5 mmol, pH 8.0) and acetonitrile, and detected by fluorescence measurements at 340 nm (excitation) and 538 nm (emission). Results : The detection limit for the urinary free 4-Hyp was $0.364{\mu}mol/l$. The recovery rate of 4-Hyp was 99.7%, and the effective pH of the phosphate buffer and borate buffer were 3.0 and 8.0, respectively. From statistical analysis, age, drinking and smoking did not affect the urinary free 4-Hyp in both the controls and workers. The range of urinary 4-Hyp in the controls, pre-shift, and post-shift workers were 0.33-16.44, N.D-49.06, and $0.32-56.27{\mu}mol/l$. From the pared-sample t-test, the urinary 4-Hyp levels in post-shift workers ($11.82{\pm}6.73\;nmmol/mg\;Cre$) were 2-fold higher than in pre-shift workers ($5.36{\pm}5.53\;nmol;/mg\;Cre$) and controls ($4.91{\pm}4.89\;nmol;/mg\;Cre$). Conclusions : This method was developed with high sensitivity, accuracy, and precision. The present method was effectively applied to analyze the urinary free 4-Hyp in both controls and workers.

Properties of Epoxy Adhesive Modified with Siloxane-imide (실록산 이미드로 개질된 변성 에폭시 수지의 물성)

  • Kim, W.;Gong, H.J.
    • Elastomers and Composites
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    • v.43 no.1
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    • pp.39-48
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    • 2008
  • Peel strength of epoxy adhesives can be increased by adding some amounts of XNBR. In this case, thermal resistance of the adhesive will be decreased by decrease of glass transition temperature of the adhesive. Epoxy resin modified with siloxane-imide was synthesized to improve thermal resistance and peel strength of the adhesive, after that the properties of modified epoxy resin were compared with the commercial epoxy resin. When 5% XNBR was added to 30% modified epoxy resin, this adhesive showed 0.42 N/mm of peel strength and $155^{\circ}C$ of glass transition temperature. These properties are enough compared to the required properties by the industry, i.e., 0.3 N/mm and $150^{\circ}C$, respectively. Weight loss of the modified epoxy resin by the treatment of nitric acid and 0.1N NaOH was reduced, but weight gain by the humid condition was increased by the presence of benzene ring and imide ring. 30% modified epoxy resin blended with 5% XNBR showed 220% improvement in tensile strength and elongation compared to the case of common epoxy resin. This is due to the flexibility of the siloxane in the modified epoxy resin.