• Title/Summary/Keyword: molecular engineering

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GRP78 Secreted by Colon Cancer Cells Facilitates Cell Proliferation via PI3K/Akt Signaling

  • Fu, Rong;Yang, Peng;Wu, Hai-Li;Li, Zong-Wei;Li, Zhuo-Yu
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.17
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    • pp.7245-7249
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    • 2014
  • Glucose regulated protein 78 (GRP78) is usually recognized as a chaperone in the endoplasmic reticulum. However, increasing evidence indicates that GRP78 can be translocated to the cell surface, acting as a signaling receptor for a variety of ligands. Since little is known about the secretion of GRP78 and its role in the progression of colon cancer we here focused on GRP78 from colon cancer cells, and purified GRP78 protein mimicking the secreted GRP78 was able to utilize cell surface GRP78 as its receptor, activating downstream PI3K/Akt and Wnt/${\beta}$-catenin signaling and promote colon cancer cell proliferation. Our study revealed a new mode of action of autocrine GRP78 in cancer progression: secreted GRP78 binds to cell surface GRP78 as its receptor and activates intracellular proliferation signaling.

Curcumin-Loaded PLGA Nanoparticles Coating onto Metal Stent by Electrophoretic Deposition Techniques

  • Nam, So-Hee;Nam, Hye-Yeong;Joo, Jae-Ryang;Baek, In-Su;Park, Jong-Sang
    • Bulletin of the Korean Chemical Society
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    • v.28 no.3
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    • pp.397-402
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    • 2007
  • Restenosis after percutaneous coronary intervention (PCI) continues to be a serious problem in clinical cardiology. To solve this problem, drug eluting stents (DES) with antiproliferative agents have been developed. Variable local drug delivery systems in the context of stenting require the development of stent manufacture, drug pharmacology and coating technology. We have worked on a system that integrates electrophoretic deposition (EPD) technology with the polymeric nanoparticles in DES for local drug delivery and a controlled release system. The surface morphology and drug loading amount of DES by EPD have been investigated under different operational conditions, such as operation time, voltage and the composition of media. We prepared poly-D,L-lactide-co-glycolic acid (PLGA) nanoparticles embedded with curcumin, which was done by a modified spontaneous emulsification method and used polyacrylic acid (PAA) as a surfactant because its carboxylic group contribute negative charge to the surface of CPNPs (?53.5 ± 5.8 mV). In the process of ‘trial and error' endeavors, we found that it is easy to control the drug loading amount deposited onto the stent while keeping uniform surface morphology. Accordingly, stent coating by EPD has a wide application to the modification of DES using various kinds of nanoparticles and drugs.

Microwave Synthesis of a Porous Metal-Organic Framework, Nickel(II) Dihydroxyterephthalate and its Catalytic Properties in Oxidation of Cyclohexene

  • Lee, Ji-Sun;Halligudi, Shiva B.;Jang, Nak-Han;Hwang, Dong-Won;Chang, Jong-San;Hwang, Young-Kyu
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1489-1495
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    • 2010
  • A porous coordination solid of nickel(II) dihydroxyterephthalate has been synthesized by the microwave-assisted (MW) method. The synthesized nickel(II) dihyroxylterephthalate was designated by the general formula of [$Ni_2$(dhtp) $(H_2O)_2]{\cdot}8H_2O$ (where, dhtp = 2,5-dihydroxyterephthalate, denoted by Ni-DHTP). The effect of microwave-irradiation temperature and time of irradiation on the porosity and morphological changes in the solids have also been investigated. The catalytic performance of Ni-DHTP synthesized by MW method has been studied in the oxidation of cyclohexene with aqueous $H_2O_2$, which gave cyclohexene oxide as the primary product and 2-cyclohexene-1-ol as a major product.

Electrodeposition of SnO2-doped ZnO Films onto FTO Glass

  • Yoo, Hyeonseok;Park, Jiyoung;Kim, Yong-Tae;Kim, Sunkyu;Choi, Jinsub
    • Journal of Electrochemical Science and Technology
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    • v.10 no.1
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    • pp.61-68
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    • 2019
  • Well aligned $SnO_2$-doped ZnO nanorods were prepared by single step or 2-step electrochemical depositions in a mixture solution of zinc nitrate hexahydrate, ammonium hydroxide solution and 0.1 M tin chloride pentahydrate. The morphologies of electrochemically deposited $SnO_2$-doped ZnO were transformed from plain (or network) structures at low reduction potential to needles on hills at high reduction potential. Well aligned ZnO was prepared at intermediate potential ranges. Reduction reagent and a high concentration of Zn precursor were required to fabricate $SnO_2$ doped ZnO nanorods. When compared to results obtained by single step electrochemical deposition, 2-step electrochemical deposition produced a much higher density of nanorods, which was ascribed to less potential being required for nucleation of nanorods by the second-step electrochemical deposition because the surface was activated in the first-step. Mechanisms of $SnO_2$ doped ZnO nanorods prepared at single step or 2-step was described in terms of applied potential ranges and mass-/charge- limited transfer.

The Application of the Pseudo Molecular Complex to Thermal Polymerization (Ⅰ). Proposal of A New Initiation Mechanism (의사분자 착물의 응용 (제1보). 열중합 개시기구 제안)

  • Byung Kack Park
    • Journal of the Korean Chemical Society
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    • v.18 no.6
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    • pp.447-452
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    • 1974
  • A mechanistic possibility for the initiation of the thermal polymerization reactions are envisaged theoretically. As result of the considerations, it is assumed that the thermal polymerization reactions take place via the pseudo molecular complex which has been supposed to be an intermediate in the transition state of Diels-Alder reactions.

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