• Title/Summary/Keyword: Moelcular

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Pathogenesis of Minimal Change Nephrotic Syndrome: A Review of the Underlying Molecular Mechanisms

  • Yang, Eun Mi
    • Childhood Kidney Diseases
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    • v.23 no.1
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    • pp.1-6
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    • 2019
  • Nephrotic syndrome (NS) is the most common glomerular disorder in childhood, and a vast majority of cases are idiopathic. The precise cause of this common childhood disease is not fully elucidated despite significant advancements in our understanding of podocyte biology. Idiopathic NS has been considered "a disorder of T-cell function" mediated by a circulating factor that alters podocyte function resulting in massive proteinuria since the last four decades. Several circulatory factors released from T-cells are considered to be involved in pathophysiology of NS; however, a single presumptive factor has not been defined yet. Extended evidence obtained by advances in the pathobiology of podocytes has implicated podocytes as critical regulator of glomerular protein filtration and podocytopathy. The candidate molecules as pathological mediators of steroid-dependent NS are CD80 (also known as B7-1), hemopexin, and angiopoietin-like 4. The "two-hit" hypothesis proposes that the expression of CD80 on podocytes and ineffective inhibition of podocyte CD80 due to regulatory T-cell dysfunction or impaired autoregulation by podocytes results in NS. Recent studies suggest that not only T cells but also other immune cells and podocytes are involved in the pathogenesis of MCNS.

Physico-Chemical Characteristics of $\alpha$-D-Glucosidase Inhibitor from Streptomyces sp (Streptomyces속 균주가 생성하는 $\alpha$-D-Glucosidase 저해물질의 물리학적 성질)

  • 도재호;주현규
    • Microbiology and Biotechnology Letters
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    • v.18 no.1
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    • pp.35-38
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    • 1990
  • $\alpha$-D-Glucosidase inhibitor purified in a pure form was amorphous powder which gave a single spot at Rf value 0.12-0.71 with various developing solvent systems on silica gel thin layer chromatography, and melting point was 154.3-155.3$^{\circ}C$. It was disolved in water, formic acid and ethylene glycol monoethyl ether, and was very high hygroscopic substance. Biochemical reaction of the substance was positive to phenol sulfuric acid, ninhydrin, silver nitrate-sodium hydroxide, but negative to DNS reagent. Acid hydrolysis gave fructose and acid as sole sugar and amino acid constituents respectively. Moelcular weight of the inhibitor was estimated to be 1,050 by Shphadex G-25 column chromatography.

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Pre-extraction of Hemicelluloses from Korean Mixed Hardwood Chips Using Hot Water and Alkali Solution and its Characteristics (열수 및 알칼리 용액을 이용한 국산 목재 칩으로부터 헤미셀룰로오스의 선추출 및 특성 구명)

  • Cho, Hwi;Shin, Hee-Nae;Sim, Kyu-Jeong;Youn, Hye-Jung;Lee, Hak-Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.43 no.1
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    • pp.83-91
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    • 2011
  • Hemicelluloses are useful materials for papermaking and other biotechnological applications. To recover and further utilize the hemicelluloses, this study carried out the pre-extraction of the hemicelluloses from Korean mixed hardwoods chips using hot water and sodium hydroxide solution at various temperature and time conditions. Through the hot water pre-extraction, the wood components of 22% was extracted and the 35% of the hemicelluloses which were contained in the original wood chips were dissolved into the pre-extractives. The yield of the pre-extractives was more significantly influenced by the pre-extraction temperature than the time. The pre-extractives with the yield of 30% could be obtained by alkali pre-extraction and alkali concentration was the most important factor. It had lower hemicellulose content but high molecular weight, compared with the hot water pre-extractives.

The crystal and molecular structure of sulfisoxazole

  • Koo, Chung-Hoe;Shin, Hyun-So;Cho, Sung-Il
    • Archives of Pharmacal Research
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    • v.5 no.2
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    • pp.79-86
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    • 1982
  • Sulfisoxazole, $C-{11}H_{13}N_{3}S$, crystallized in the orthohombic system, space group Pbca, with a = 14.492(1), b = 11.563(1), c = 14.900(2) $\AA$ and Z = 8. Intensities for 1867(1360 observed) unique reflections were measured on a four-circle diffractometer wirh CuKa radiation ($\lambda$ = 1.5418$\AA$). The structure was solved by heavy atom methods and refined by full-matrix least-squares procedures to a final R of 0.094. The benzene ring plane makes an angle of $68^{\circ}C$ with the plane of the isoxazole ring, which is plannar. The conformational angle formed by the torsional angle C(4)-S-N(2)-C(7) is $54^{\circ}C$. There are two intermolecular hydrogen bonds in the structure. One of them is of the type N-H...H with the length 2.915$\AA$. Thus two dimensional networks of hydrogen bonds form infinite moelcular sheets parallel to the (001) plane. Adjacent sheets are bound together by van der Waals forces.

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Preparation of Monodisperse Poly(Acrylic acid) with a Water-Soluble Initiator by Solution Polymerization in Aqueous Phase (수용액 내에서 수용성개시제를 이용한 단분산성 폴리아크릴산의 용액중합)

  • Park, Moonsoo;Kim, Yeji
    • Elastomers and Composites
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    • v.49 no.3
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    • pp.232-238
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    • 2014
  • Solution polymerization was conducted with water-soluble acrylic acid (AA) as a monomer and potassium persulfate (KPS) as an initiator at a selected temperature between $60^{\circ}C$ and $90^{\circ}C$ with water as a reaction medium. When the ratio between AA and water was reduced or initiator concentration increased, molecular weights decreased. An increase in the reaction temperature produced lower molecular weights. The polydispersity index was close to 1.5 in most of the reactions. An increase in the stirring speed up to 400 rpm led to a progressive increase in molecular weights. When the stirring speed reached 800 rpm, however, we found that both the number and weight average molecular weights decreased. The glass transition temperature was nearly independent of moelcular weights and determined to be between $113^{\circ}C$ and $116^{\circ}C$.