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Featured researches published by Chang-Shik Choi.


Rapid Communication in Photoscience | 2013

HPLC analysis and in vitro study of the extract from Punica granatum peel

Min San Kim; Chang-Shik Choi

The extract of Punica granatum peel was separated and confirmed by HPLC, and punicalagin, one of the extract, was better antibacterial activity against Salmonella.


Rapid Communication in Photoscience | 2014

Coculture of Schwann Cells and Neuronal Cells for Myelination in Rat

Ji-Young Kim; Chang-Shik Choi; Seong-Karp Hong

For in vitro myelination system, Schwann cells and neuronal cells of rat were cocultured. Schwann cells and neuronal cells, respectively, were obtained from dorsal root ganglion of rat embryos (E15). This method includes four steps: first step of suspension of the embryonic dorsal root ganglion cells, second step of addition of anti-mitotic cocktail, third step of purification of dorsal root cells, and fourth step of addition of Schwann cells to dorsal root ganglion cells. We made a highly purified population of myelination in a short period through this procedure and identified myelination basic protein using antibody of myelination basic protein.


Medicinal Chemistry | 2018

Facile synthesis, crystal structure, DFT calculation and biological activities of 4-(2-fluorophenyl)-3-(3-methoxybenzyl)-1H-1,2,4-triazol-5(4H)-one (5)

Muhammad Saleem; Muhammad Rafiq; Yeon Ki Jeong; Dae Won Cho; Chong-Hyeak Kim; Sung-Yum Seo; Chang-Shik Choi; Seong-Karp Hong; Ki-Hwan Lee

BACKGROUND In the past few decades, design, synthesis, and characterization of novel heterocyclic compounds with auspicious biological profile received the considerable attention of the scientific community. Among them, the small and simple organic molecular backbone like triazole moiety have a broad spectrum of applications in the medicinal as well as diagnostic areas. OBJECTIVE The objective of present study was synthesis, characterization, and exploration of biological profile of 4-(2-fluorophenyl)-3-(3-methoxybenzyl)-1H-1,2,4-triazole-5(4H)-one (5). The tautomeric interconversion of the molecule was observed by the single crystal XRD and DFT analysis. METHODS N-(2-fluorophenyl)-2-[2-(3-methoxyphenyl)acetyl]hydrazine carboxamide (4) was synthesized by the condensation of 2-(3-methoxyphenyl)acetohydrazide (3) with 1-fluoro-2- isocyanatobenzene. The dehydrocyclization of compound (4) yielded target compound (5) by refluxing in 2 N aqueous sodium hydroxide solutions. The target molecule was characterized by FTIR, 1H NMR, 13C NMR, single crystal X-ray diffraction analysis and DFT calculation. The enzymatic assay measurements were carried out by using a microplate reader (OPTI Max, Tunable Microplate Reader; Wavelength range: 340-850 nm; for 96-well plates) while DFT calculation was performed by Gaussian 09 package. RESULTS The XRD result and DFT calculations showed that molecule 5 predominantly exists in thione conformation and crystallized in the triclinic system of P-1 space group. Furthermore, for the practical applicability of synthesized compound 5, the in vitro acetylcholinesterase as well as α-glucosidase inhibition activities were performed and found moderate enzyme inhibition potential comparable with that of reference inhibitors. CONCLUSION This study might be helpful for future design and development of potent enzyme inhibitor to control Alzheimers as well as diabetic disease. The DFT and single crystal XRD analysis data might be helpful for understanding the mechanism of drug binding and its mode of action.


Rapid Communication in Photoscience | 2016

Induction of Demyelination by Infection of Semliki Forest Virus

Hyun Joo Kim; Chang-Shik Choi; Seong-Karp Hong

Schwann cells and neuronal cells from dorsal root ganglion (DRG) in embryos of rat were cultured in vitro respectively. The purified neuronal cells with anti-mitotic agents and purified Schwann cells were co-cultured and then accomplished myelination processing. Infection of Semliki forest virus into this myelinated coculture system was performed and then accomplished demyelination. We identified myelination and demyelination processing using antibody of neuropeptide Y. Many viruses such as Theiler’s virus, mouse hepatitis virus (MHV), corona, measles, herpes viruses, and Semliki Forest virus are known as cause of inducing demyelination (meaning destruction of myelination) in nervous system of mice. Especially Semliki Forest virus infection induces a demyelinating encephalomyelitis in the central nervous system of mice. Mice and rats are used as an important model for the study of myelination and demyelination research in vitro and in vivo. Generally adult mammalian DRG neuron cells can survive and regenerate in culture. In vitro myelination had been established by co-culturing with pure populations of primary Schwann cells and primary neuronal cells. These pure populations of primary Schwann cells and primary neuronal cells were driven from DRG of rat embryos. This method produced highly purified populations of Schwann cells and neuronal cells faster than any other conventional method. From this research, we constructed a population of myelinated cells with co-culture of neuronal cells and Schwann cells from DRG. After this myelinated cells were infected with Semliki Forest virus and processing of demyelination was progressed. We could identify and distinguish myelination and demyelination processing using antibody of neuropeptide Y which represented as myelinated cells. Cultures were incubated at 37 °C, with 5% CO2. 24 h later, 50 mL of NGF stock solution (40 mM of 5-fluorodeoxyuridine and uridine, 1 mM Arabinofur-anosyl Cytidine (Ara C, Sigma-Aldich, Saint Louis, MO) in NG medium) was added into each well to make the final concentration of 5-fluorodeoxyuridine/uridine 20 mM. Cultures were incubated at 37 °C in a 5% CO2 incubator. 6 After 72 hours, 2/3 of the NGF stock solution was changed to NG medium and the cultures were re-fed every 2 days with NG medium. After three medium changes, the neurons were ready for the Schwann cell addition. Schwann cells were digested and washed once with DMEM (Invitrogen, Carlsbad, CA) containing 10% FBS, and then resuspended in C medium (MEM, 10% FBS, 2mM l-glutamine, 0.4% glucose, and 50 ng/mL 2.5 S NGF). 100 mL (approximately 200,000 cells) of Schwann cells was added to each of the DRG cultures in C media. After 3 days, the co-cultures were supplemented with 50 mg/mL of ascorbic acid to initiate basal lamina formation and myelination. Myelination was allowed to proceed for up to 21 days. The process of myelination was observed and recorded under phase contrast microscope. To observe the formation of the myelin, the DRG neuron/Schwann co-cultures (14 days after initiation myelin formation) were then labeled with primary antibodies, which included monoclonal antibody against neuropeptide Y. After three washes with PBS, the coverslips were further incubated with Alexa Fluor 488 mouse antirabbit IgG and Alexa Fluor 594 goat anti-mouse IgG (Invitrogen, Carlsbad, CA) for 60 min at room temperature. After a final wash in PBS, the slides were mounted with mounting fluid (DAKO Ltd., Carpenteria, CA) and visualized under a fluorescence microscope (Olympus, Tokyo, Japan). The images were digitally recorded and processed with Image-Pro Plus (Media Cybernetics, Atlanta, GA). Processing for co-culture of Schwann cells and neuronal cells for myelination from DRG of rat embryos was described. This procedure contains following four steps: first step of suspension of the embryonic dorsal root ganglion cells, second step of addition of anti-mitotic cocktail, third step of purification of dorsal root cells, and fourth step of addition of Schwann cells to dorsal root ganglion cells. As a result of this study, for formation of myelination, Schwann cells and neuronal cells, respectively, were prepared and cultured from DRG of rat embryos (E 16 day) (Figure 1). Figure 1. Purification of populations of Schwann cells and neuronal cells, respectively, from DRG of rat embryo (E 16 day) (A: DRG cells; B: neuronal cells; C: Schwann cells). To identify and distinguish myelination and demyelination processing, population of cells were labeled with monoclonal antibody against neuropeptide Y and observed by fluorescent microscope. Population of myelinated cells represents fluorescent spots due to monoclonal antibody against neuropeptide Y which binds myelinated proteins. On the other hand, population of *To whom correspondence should be addressed. E-mail: [email protected], [email protected] Communication Hyun Joo Kim, Chang-Shik Choi, and Seong-Karp Hong This Journal is


Rapid Communication in Photoscience | 2016

Fluorescent Compounds Having the Spaced and Integrated Type Receptors

Chang-Shik Choi

Fluorescent receptors have gained much attention because of their usefulness in analysis and clarification of the roles of biomolecules in living systems. Molecular structures of the integrated type including that the receptor itself is fluorescent, and play an important role in having the functionality or selectivity of the fluorescent compounds. These spaced type fluorescent receptors are required to have special molecular design in order to transmit the information of molecular recognition to the fluorescent unit through the spacer unit. Compared with the spaced type fluorescent receptors, number of the integrated type receptors is limited due to the difficult molecular design and synthesis. Modification of alteration of the fluorophore frequently caused deterioration of the fluorescent property. Various spaced type and integrated type fluorescent receptors including switch on-off receptors are introduced in this article.


Rapid Communication in Photoscience | 2015

Generation of Demyelination through Use of M. leprae-specific phenolic glycolipid-1 (PGL-1)

Ji-Young Kim; Chang-Shik Choi; Seong-Karp Hong

For myelination, Schwann cells and neuron cells from dorsal root ganglion (DRG) of rat embryos (E16) were cultured in vitro system. The purified DRG cells with anti-mitotic agents and purified Schwann cells were cocultured and then accomplished myelination processing. Treatment of M. leprae-specific phenolic glycolipid-1 (PGL-1) into this coculture system was performed and then accomplished demyelination. Therefore, we identified demyelination processing using antibody of myelin basic protein (MBP). The study of Schwann cell, Neuronal cell, and myelination has been facilitated by the availability to isolate and establish pure population of primary Schwann cells. Moreover, mice serve as an important model for the study of Schwann cell research. The specialized source of neurons from nonneuronal cells were provided in dorsal root ganglia. 1 Adult mammalian DRG neuron cells can survive and regenerate in culture. 2,3,4 There are several researches on purified populations of these neurons. Coculture of purified DRG neurons and Schwann cells can be used in myelin formation. The most widely used method for preparing primary Schwann cell culture uses DRG as the primary source of Schwann cells. The procedure is very simple and produces a highly purified population of Schwann cells in a short time. The method has also been used to prepare Schwann cells from mouse embryos. In this study, we performed a purified population of myelination by coculture of DRG neuronal cells and Schwann cells. The purified DRG cells with anti-mitotic agents and purified Schwann cells were cocultured and then accomplished myelination processing. Treatment of M. leprae-specific phenolic glycolipid-1 (PGL-1) into this coculture system was performed and then accomplished demyelination. Therefore, we identified demyelination processing using antibody of myelin basic protein (MBP). Cultures were incubated at 37 ℃, with 5% CO2. 24 h later, 150 mL of NGF stock solution (40 mM of 5-fluorodeoxyuridine and uridine, 1 mM Arabinofur-anosyl Cytidine (Ara C, Sigma-Aldich, Saint Louis, MO) in NG medium) was added into each well to make the final concentration of 5-fluorodeoxyuridine/uridine 20 mM. Cultures were incubated at 37 ℃ in a 5% CO2 incubator. 5 After 72 hours, 2/3 of the NGF stock solution was changed to NG medium and the cultures were re-fed every 2 days with NG medium. After three


Rapid Communication in Photoscience | 2014

Molecular Wire World Having Metal Complexes

Chang-Shik Choi

ABSTRACT: Development of molecular and supramolecular systems showing efficient photoinduced energy or electron transfer are of current research interest due to their applications in various chemical and biological processes. Various polypyridine metal complexes including Ru(II), Ru(III), Os(II), Pt(II), Fe(II), Re(I), Ir(III) and so on as a metal center introduce for expanding some more understanding of molecular-scale photoelectronics. Their complexes are concisely classified by the types of relay ligands as follows; (a) metal-direct ligand-metal system; dinuclear or trinuclear systems, (b) metal-nonconjugated ligand-metal system and metal-nonconjugated ligand system having flexible/rigid ligand, (c) metal-conjugated ligand-metal system, and (d) conjugated ligand-metal-conjugated ligand system and metal-self assembly ligand-metal system. It is pointed out that the role played by the relay ligands is important in constructing the metal complexes. INTRODUCTION The appearance of the polypyridine metal complexes has triggered an extensive growth in photochemistry and photophysics, because of their highly versatile luminescent and photoredox properties. In the last few years the increasing interest in photoinduced energy- and electron-transfer processes in supramolecular systems


Rapid Communication in Photoscience | 2012

The Fluorescent 7-Aminodipyrido[3,2-a:2`,3`-c] phenazine(7-amino-dppz) Functionalized as an Europium Ion (

Chang-Shik Choi; Ki-Hwan Lee

The Fluorescent 7-aminodipyrido[3,2-a:2`,3`-c]phenazine (7-amino-dppz, 1) is functionalized as an europium ion () sensor, which showed the effective emission quenching when europium cation is chelated to the bpy site of 1 compound. The complexation ratio indicated that the 1 compound forms a 1 : 1 complex with .


Rapid Communication in Photoscience | 2012

Eu^{3+}

Doan Minh Phung; Woo-Chul Jeong; Chang-Shik Choi; Ki-Hwan Lee

, H, F, and Cl), respectively, showed plateshape. We were known from these results that thesubstituent of ending group played an important role in thecrystallization of single molecule and the morphology ofnaphthalic derivatives could be controlled by only change ofending group in single molecule.Nowadays, the photofunctional fluorescent materials is beingactively studied for two reasons: first, the understanding ofthe physical processes in such systems is of fundamentalinterest and second, the prospects of their practicalapplication for developing sensory, biochemical, medical,photo-electronic, illuminating light sources, flat displays andamong other possible uses seem to be very attractive.


Journal of Luminescence | 2004

) Sensor

Chang-Shik Choi; Mi-Kyoung Kim; Ki-Seok Jeon; Ki-Hwan Lee

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Ki-Hwan Lee

Kongju National University

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Ki-Seok Jeon

Kongju National University

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Seong-Karp Hong

Catholic University of Korea

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Mi-Kyoung Kim

Kongju National University

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Seung-Koo Lee

Kongju National University

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Muhammad Rafiq

Pakistan Institute of Development Economics

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