• Korean Journal of Environmental Biology
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• v.22 no.4
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• pp.519-523
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• 2004

This study sought to investigate the ameliorating effects of a Korean medicinal herb (KMH) complex on the impacts of alcohol consumption in rat hepatocytes and in reducing the total cholesterol levels and the total lipid levels in the serum. We compared the body weight gain and ratio of the liver, the kidney to body weight, and also the serum biochemistry of the rats administered with both the alcohol and the KMH complex to the control rats treated with alcohol alone. The clinically important enzyme markers (Aspartate Aminotransferase, AST, and Alanine Aminotransferase, ALT) of rats, administered with both the alcohol and the KMH complex treatments, were compared with those in the control group. The treatment regimen (KMH complex) significantly reduced the serum AST and ALT levels, indicating the hepato-protective effects of the KMH complex. Furthermore, total cholesterol and total lipid levels were significantly reduced. These results indicate that the KMH complex may positively mediate the effects of alcohol on hepatocytes and the general liver functions.

• Journal of Microbiology and Biotechnology
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• v.12 no.2
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• pp.286-291
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• 2002

Histone deacetylase I (HDAC1) works as one of the components in a nucleosome remodeling (NuRD) complex that consists of several proteins, including metastasis-associated protein 1 (MTA1). Since the protein-protein interaction of HDAC1 and MTA1 would appear to be important for both the integrity and functionality of the HDAC1 complex, the interruption of the HDAC1 and MTA1 interaction may be an efficient way to regulate the biological function of the HDAC1 complex. Based on this idea, a yeast two-hybrid system was constructed with HDAC1 and MTA1 expressing vectors in the DNA binding and activation domains, respectively. To verify the efficiency of the assay system, 3,500 microbial metabolite libraries were tested using the paper disc method, and KB0699 was found to inhibit the HDAC1 and MTA1 interaction without any toxicity to the wild-type yeast. Furthermore, KB0699 blocked the interaction of HDAC1 and MTA1 in an in vitro GST pull down assay and induced morphological changes in B16/BL6 melanoma cells, indicating the interruption of the HDAC1 complex function. Accordingly, these results demonstrated that the yeast assay strain developed in this study could be a valuable tool for the isolation of a HDAC1 complex disruptor.

• Macromolecular Research
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• v.14 no.1
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• pp.66-72
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• 2006

The purpose of this study is to develop novel nanoparticles based on polyion complex formation between low molecular weight water-soluble chitosan (LMWSC) and all-trans retinoic acid (atRA). LMWSC nanoparticles encapsulating atRA based on polyion complex were prepared by mixing of atRA into LMWSC aqueous solution using ultrasonication. In FTIR spectra, the carbonyl group of atRA at 1690 $cm^{-1}$ disappeared or decreased when ion complexes were formed between LMWSC and atRA. In ${1}^H$ NMR spectra, specific peaks of atRA disappeared when atRA-encapsulated LMWSC (RAC) nanoparticles were reconstituted into $D_{2}O$ while specific peaks both of atRA and LMWSC appeared in $D_{2}O$/DMSO (1/3, v/v) mixture. XRD patterns also showed that the crystal peaks of atRA were disappeared by encapsulation into LMWSC nanoparticles. LMWSC nanoparticles encapsulating atRA have spherical shapes with particle size below 200 nm. The mechanism of encapsulation of atRA into LMWSC nanoparticles was thought to be an ion complex formation between LMWSC and atRA. LMWSC nanoparticles showed high atRA loading efficiency over 90$\%$ (w/w). AtRA was continuously released from nanoparticles over 10 days. In in vitro cell cytotoxicity test, free atRA showed higher cytotoxic effect against CT 26 colon carcinoma cell line on 1 day. However, RAC nanoparticles showed similar cytotoxicity against CT 26 cells on 2 day. These results suggest the potential for the introduction of LMWSC nanoparticles into various biomedical fields such as drug delivery.

• Natural Product Sciences
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• v.19 no.2
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• pp.173-178
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• 2013

The protective effect of SAPP, an extract from a novel herbal complex, on acute liver injury was investigated using mouse animal model in this study. The content of total phenol in SAPP was increased at dose dependent manner. Consistent with the content of total phenol, SAPP showed the significant anti-oxidative effects on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) method. Acute liver injury was induced by D-galactosamine (D-GalN) in mouse. Treatment with SAPP significantly reduced the level of alanine transaminase (ALT) and aspartate transaminase (AST) in serum. Histological observation revealed that whereas D-GalN treated mouse showed vacuolization of hepatocytes, sinusoidal dilation and congestion, loss of cell boundaries and ballooning degeneration, loss of architecture and cell necrosis, treatment with SAPP improved D-GalN-induced liver injury. These results suggest that SAPP shows protective effects against D-GalN-induced hepatotoxicity in vivo acute mouse model.

• BMB Reports
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• v.33 no.2
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• pp.155-161
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• 2000

The saccharomyces cerevisiae Rad27, a structure-specific endonuclease for the okazaski fragment maturation has been known to interact genetically and biochemically with Dna2, an essential enzyme for DNA replication. In an attempt to define the significance of the interaction between the two enzymes, we expressed and purified both Dna2 and Rad27 proteins. In this report, Rad27 could not form a complex with Dna2 in the three different analyses. The analyses included glycerol gradient sedimentation, protein-column chromatography, and coinfection of baculoviruses followed by affinity purification. This is in striking contrast to the previous results that used crude extracts. These results suggest that the interaction between the two proteins is not sufficiently stable or indirect, and thus requires an additional protein(s) in order for Rad27 and Dna2 to form a stable physical complex. This result is consistent with our genetic findings that Schizosaccharomyces pombe Dna2 is capable of interacting with several proteins that include two subunits of polymerase $\delta$, DNA ligase I, as well as Fen-1. In addition, we found that the N-terminal modification of Rad27 abolished its enzymatic activity. Thus, as suspected, we found that on the basis of the structure determination, N-terminal methionine indeed plays an important role in the nucleolytic cleavage reaction.

• YAKHAK HOEJI
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• v.40 no.6
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• pp.697-704
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• 1996

Quinolone derivatives, SJ5b (ethyl 5,12-dihydro-5-dihydro-5-oxobenzoxazolo[3,2-a]quinoline-6-carboxylate) and SQ7b (3-fluoro-2-(4-methylpiperazin-1-yl)-5.12-dihydro-5-oxobenzoxa zolo[3,2-a]quinoloine carboxylic acid) showed in vitro cytotoxicities against various tumor cell lines. SJ5b and SQ7b completely inhibited the DNA relaxation activities of human placental topoisomerase II at the concentration of 15.63 and 1.95 ${\mu}$g/ml, respectively. However, unlike etoposide which stabilize the topoisomerase II-DNA complex, SQ7b did not cause topoisomerase II-mediated DNA cleavage and SJ5b weakly stabilized the topoisomerase II-DNA cleavable complex. Through both experiments. DNA relaxation assay by the increment of topoisomerase II concentration and DNA unwinding assay, it was shown that SJ5b and SQ7b did not interact with topoisomerase II itself but bound to DNA. Therefore, it was concluded that DNA binding of SJ5b and SQ7b caused the inhibition of topoisomerase II related to DNA relaxation but no or very weak stabilization of topoisomerase II-DNA cleavable complex. In addition, SJ5b and SQ7b prevented whole cell nucleic acid syntheses in HL60 cells.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1095-1099
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• 1998

The crystal structure of an acetylene sorption complex of dehydrated fully Mn(Ⅱ)-exchanged zeolite X, Mn46Si100Al92O384·30C2H2 (a=24.705(3) Å) has been determined by single-crystal X-ray diffraction techniques. The structure was solved and refined in the cubic space group Fd3 at 21(l) ℃. The complex was prepared by dehydration at 380 ℃ and 2 x 10-6 Torr for 2 days, followed by exposure to 300 Torr of acetylene gas for 2 h at 24 ℃. The structure was refined to the final error indices, R1=0.060 and R2=0.054 with 383 reflections for which I > 3σ(Ⅰ). In the structure, Mn2+ ions are located at two different crystallographic sites; sixteen Mn2+ ions at site I are located at the centers of the double six rings and thirty Mn2+ ions are found at site Ⅱ in the supercage, respectively. Each of these latter Mn2+ ions is recessed ca. 0.385(2) Å into the supercage from its three-oxygen plane. Thirty acetylene molecules are sorbed per unit cell. Each Mn2+ ion at site Ⅱ lies on a threefold axis in the supercage of the unit cell, close to three equivalent trigonally arranged zeolite framework oxygen atoms (Mn(Ⅱ)-O=2.135(9) Å) and symmetrically to both carbon atoms of a C2H2 molecules. At these latter distances, the Mn(Ⅱ)-C interactions are weak (Mn(Ⅱ)-C=2.70(5) Å), probably resulting from electrostatic attractions between the divalent cations and the polarizable π-electron density of the acetylene molecules.

• Journal of Physiology & Pathology in Korean Medicine
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• v.33 no.3
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• pp.169-174
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• 2019

The purpose of this study was to evaluate the inhibitory effects of Juglans regia complex extract(JCE) consisted of Juglans regia, Eucommia ulmoides, Eleutherococcus senticosus and Zingiber officinale on osteoclast differentiation. Cell toxicity test by using CCK-8, TRAP activity and TRAP positive multi-nucleated cell counting were performed to evaluate inhibitory effect on differentiation of osteoclast from bone marrow derived macrophages(BMMs) induced by receptor activator of nuclear $factor-{\kappa}B$ ligand(RANKL). As a result, JCE inhibited RANKL-induced osteoclast differentiation in BMMs dose-dependently without cytotoxicity. These results suggest that JCE may have a potential role for treating bone lytic diseases such as osteoporosis.

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.178-181
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• 1991

The crystal structure of dehydrated fully $Cd^{2+}$-exchanged zeolite A evacuated at $2{\times}10^{-6}$ Torr and $450^{\circ}C (a = 12.225(2){\AA})$ and of its ethylene sorption complex (a = 12.219(2) ${\AA}$) have been determined by single crystal X-ray diffraction techniques in the cubic space group Pm3m at $21(1)^{\circ}$. The structures were refined to final error indices, $R_1$ = 0.063 and $R_2$ = 0.065 with 266 reflections and $R_1$ = 0.055 and $R_2$ = 0.062 with 260 reflections, respectively, for which $I{\gg}3{\sigma}(I)$. In both structures, six $Cd^{2+}$ ions lie at two distinguished three-fold axes of unit cell. Dehydrated $Cd_6$-A sorbs 4 ethylene molecules per unit cell at $25^{\circ}C$ (vapor pressure of ethylene is ca. 100 Torr). Each $Cd^{2+}$ ion forms a lateral ${pi}$ complex with an ethylene molecule. Four $Cd^{2+}$ ions exist in a nearly tetrahedral environment, 2.210(7)${\AA}$ apart from three framework oxygen ions (considering ethylene molecule as a monodentate ligand) and $2.67(6){\AA}$ from each carbon atom of ethylene molecule.

• Journal of Microbiology and Biotechnology
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• v.32 no.8
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• pp.1034-1040
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• 2022

Fas-associated death domain (FADD) is an adapter molecule that bridges the interaction between receptor-interacting protein 1 (RIP1) and aspartate-specific cysteine protease-8 (caspase-8). As the primary mediator of apoptotic cell death, caspase-8 has two N-terminal death-effector domains (DEDs) and it interacts with other proteins in the DED subfamily through several conserved residues. In the tumor necrosis receptor-1 (TNFR-1)-dependent signaling pathway, apoptosis is triggered by the caspase-8/FADD complex by stimulating receptor internalization. However, the molecular mechanism of complex formation by the DED proteins remains poorly understood. Here, we found that direct DED-DED interaction between FADD and caspase-8 and the structure-based mutations (Y8D/I128A, E12A/I128A, E12R/I128A, K39A/I128A, K39D/I128A, F122A/I128A, and L123A/I128A) of caspase-8 disrupted formation of the stable DED complex with FADD. Moreover, the monomeric crystal structure of the caspase-8 DEDs (F122A/I128A) was solved at 1.7 Å. This study will provide new insight into the interaction mechanism and structural characteristics between FADD and caspase-8 DED subfamily proteins.