• The Journal of Internal Korean Medicine
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• v.24 no.1
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• pp.75-83
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• 2003

Objectives : Peroxynitrite($ONOO^-$), formed from the reaction of $O2^-$ and NO, is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been involved in the aging process and age-related diseases such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate scavenging activities of $ONOO^-$ and its precursors, NO and $O_{2^-}$ and its scavenging mechanism of Zingiberis Rhizoma (ZR). Methods : To investigate scavenging activities of $ONOO^-,\;NO,\;O_{2^-}$ and its scavenging mechanism, we used fluorescent probes like DCFDA, DAF-2 and DHR 123. The $ONOO^-$ scavenging activity on ZR was assayed by measuring oxidized dihydrorhodamine 123 (DHR 123) by fluorometry. The scavenging efficacy was expressed as IC50, showing the concentration of each sample that is required to cause 50% inhibition of DHR 123 oxidation. In a separate study, the protective effect of ZR on $ONOO^-$-induced nitration of bovine serum albumin was investigated through immuno-assay with a monoclonal anti-nitryrosine antibody, and a horseradish peroxidase-conjugated anti-mouse secondary antibody from sheep. Results : ZR markedly scavenged authentic $ONOO^-,\;O_{2^-}$ and NO. It also inhibited $ONOO^-$ induced by $O_{2^-}$ and NO which are derived from SIN-1. The data demonstrated that ZR led to decreased $ONOO^-$ mediated nitration of tyrosine through electron donation. It also inhibited the nitration of bovine serum albumin induced by $ONOO^-$ in a dose-dependent manner. Furtheremore, it blocked LPS-induced ROS and RNS generation. Conclusions : These results suggest that ZR can be developed as an effective $ONOO^-$ scavenger for the prevention of aging process and age-related diseases.

• The Journal of Korean Society of Virology
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• v.28 no.3
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• pp.225-232
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• 1998

We have expressed GFP in Sf9 and Bm5 cells or Bombyx mori larvae by using Ac-Bm hybrid virus capable of replicating in both Bm5 and Sf9 cells. Genomic DNA of Ac-Bm hybrid virus expressing ${\beta}$-galactosidase was cotransfected with baculovirus transfer vector containing GFP gene, pBacPAK-GFP in Sf9 cells. The Ac-Bm hybrid virus harboring GFP was named as Ac-Bm hybrid virus-GFP. The Ac-Bm hybrid virus-GFP-infected insect cells were easily selected by detecting the emission of GFP from each well of cell culture dish on the UV illuminator. GFP produced by Ac-Bm hybrid virus-GFP in Sf9 and Bm5 cells or B. mori larvae was confirmed by SDS-PAGE and Western blot analysis using GFP antibody. In addition, B. mori larvae infected with Ac-Bm hybrid virus-GFP was apparently appeared fluorescence from the whole body at S days postinoculation. The fluorescence of GFP from the hemolymph and fat body of B. mori larvae infected with Ac-Bm hybrid virus-GFP was also observed by fluorescence microscope. In conclusion, our results demonstrated that in baculovirus expression vector system, use of Ac-Bm hybrid virus have an additional advantage of expanded host range for producing recombinant proteins.

• The Journal of Internal Korean Medicine
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• v.26 no.1
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• pp.107-118
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• 2005

Objectives : Peroxynitrite $(ONOO^-)$, fonned from the reaction of $O_2^-$ and NO, is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been implicated in the aging process and age-related disease such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. Due to the lack of endogenous enzymes to thwart $ONOO^-$ activation, developing a specific $ONOO^-$ scavenger is remarkably important. The aim of this study was to investigate scavenging activities of $ONOO^-$ and its precursors, NO and $O_2^-$ and its scavenging mechanism of Ojawhan. Methods : To investigate scavenging activities of $ONOO^-$, NO, $O_2^-$ and its scavenging mechanism using fluorescent probes, DCFDA, DAF-2 and DHR 123. The $ONOO^-$ scavenging activity on Ojawhan was assayed by measuring oxidized dihydrorhodamine 123 (DHR 123) by fluorometry. Oxidative stress was induced by strong oxidants t-butyl hydroperoxide (t-BHP). Endothelial cell (YPEN-1) was used for detection of intracellular oxidative stress. Results : Ojawhan markedly scavenged authentic $ONOO^-$, $O_2^-$ and NO. It also inhibited $ONOO^-$ induced by $O_2^-$ and NO which are derived from SIN-1. Furthennore, ${\underline{Ojawhan}}$ blocked lipopolysaccharide (LPS)-induced $ONOO^-$, $O_2^-$ and NO generation utilizing kidney homogenates of LPS-injected mouse and inhibited t-BHP-induced ROS and $ONOO^-$ in endothelial cell culture system. Conclusions : These results suggest that Ojawhan be developed as an effective $ONOO^-$ scavenger for the prevention of $ONOO^-$ involved diseases and age-related diseases.

• Journal of Microbiology and Biotechnology
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• v.24 no.1
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• pp.70-79
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• 2014

In an attempt to develop a variety of expression vector systems for Corynebacterium glutamicum, six types of promoters, including $P_{tac}$, $P_{sod}$, $P_{sod}$ with a conserved Shine-Dalgarno (SD) sequence from C. glutamicum, $P_{ilvC}$, $P_{ilvC}$ with a conserved SD-1 ($P_{ilvC-M1}$), and $P_{ilvC}$ with a conserved SD-2 ($P_{ilvC-M2}$), were cloned into a modified shuttle vector, pCXM48. According to analysis of promoter strength by quantitative reverse transcription PCR, $P_{sod}$ and $P_{sod-M}$ were superior to tac and ilvC promoters in terms of transcription activity in C. glutamicum. All of the promoters have promoter activities in Escherichia coli, and $P_{sod-M}$ displayed the highest level of transcriptional activity. The protein expression in constructed vectors was evaluated by measuring the fluorescence of green fluorescent protein (GFP) and SDS-PAGE. C. glutamicum harboring plasmids showed GFP fluorescence with an order of activity of $P_{ilvC}$ > $P_{ilvC-M1}$ > $P_{sod}$ > $P_{ilvC-M2}$ > $P_{sod-M}$, whereas all plasmids except pCSP30 with $P_{sod}$ displayed fluorescence activities in E. coli. Of them, the strongest level of GFP was observed in E. coli with $P_{sod-M}$, and this seems to be due to the introduction of the conserved SD sequence in the translational initiation region. These results demonstrate that the expression vectors work well in both C. glutamicum and E. coli for the expression of target proteins. In addition, the vector systems harboring various promoters with different strengths, conserved SD sequences, and multiple cloning sites will provide a comfortable method for cloning and gene expression, and consequently contribute to the metabolic engineering of C. glutamicum.

• Journal of Life Science
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• v.25 no.4
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• pp.385-389
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• 2015

In this study, it is reported that a large polyprotein can be stoichiometrically cleaved by the use of caspase-3-dependent proteolysis. Previously, it has been shown that the proteolytic IETD motif was partially processed when treated with caspase-3, while the DEVD motif was completely cleaved. The cleavage efficiency of the DEVD-based substrate was approximately 2.0 times higher than that of the IETD substrate, in response to caspase-3. Based on this, 3 protein genes of interest were genetically linked to each other by adding two proteolytic cleavage sequences, DEVD and IETD, for caspase-3. Particularly, glutathione-S transferase (GST), maltose binding protein (MBP), and red fluorescent protein (RFP) were chosen as model proteins due to the variation in their size. The expressed polyprotein was purified by immobilized metal ion affinity chromatography (IMAC) via a hexa-histidine tag at the C-terminal end, showing 93 kDa of a chimeric GST:MBP:RFP fusion protein. In response to caspase-3, cleavage products, such as MBP:RFP (68 kDa), MBP (42 kDa), RFP (26 kDa), and GST (25 kDa), were separated from a large precursor GST:MBP:RFP (93 kDa) via SDS-PAGE. The results obtained from this study indicate that a multi-protein can be stoichiometrically produced from a large poly-protein by using proteolytic recognition motifs, such as DEVD and IETD tetra-peptides, for caspase-3.

• Applied Biological Chemistry
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• v.16 no.1
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• pp.31-40
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• 1973

Azotobacter vinelandii cell extracts and its variety of purified fractions with regard to their ability to form the redox state of the Shethna Flavoprotein (free radical form FPH.) were studied. A fluorescent flavoprotein (protein I) and a brown protein (protein II) were the most active proteins which were isolated in purified form. The free radical formation activity was substantially decreased during the purification and was completely lost upon storage in a week under nitrogen in a frozenstate. The presence of free flavin (FMN) with NADH enhanced the rate of free radical formation. The reaction of FMN and NADH was found to be catalysed by various cell fractions. A possible role of FMN as a substrate for free radical shethna flavoprotein was investigated. Slower reaction rate of $FMNH_2+Flavoprotein\;(FP){\to}FPH+FMN$ than $FMN+NADH{\to}FMNH_2$, accumulation of $FMNH_2$ ocurred which subsquently caused FPH.

• The Journal of Internal Korean Medicine
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• v.27 no.3
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• pp.688-697
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• 2006

Objectives : Peroxynitrite ($ONOO^-$), $O_2^-$ and nitric oxide (NO) are cytotoxic species that can oxidize several cellular components such as proteins. lipids and DNA. It has been implicated in the aging process and age-related disease such as Alzheimer's disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate $ONOO^-$ scavenging activities. and that of its precursors. NO and $O_2^-$ of Trigonellae Semen. Methods : To investigate $ONOO^-$. NO. $O_2^-$ scavenging activities, fluorescent probes, namely 2'.7'-dichlorodihydrofluorescein diacetate (DCFDA). 4.5-diaminofluorescein (DAF-2) and dihydrorhodamine 123 (DHR 123) were used. Protein expression levels of iNOS, COX-2, NF-${\kappa}B$, and VCAM-1 were assayed by western blot. Results : Trigonellae Semen markedly scavenged authentic $ONOO^-$, $O_2^-$ and NO. It also inhibited $ONOO^-$ induced by $O_2^-$ and NO which are derived from SIN-1. Furthermore. Trigonellae Semen inhibited $ONOO^-$, $O_2^-$ and NO generation in LPS-treated ICR mouse kidney postmitochondria. Trigonellae Semen inhibited gene expression of iNOS, COX-2, VCAM-l and NF-${\kappa}B$ (p65) activation. Conclusions : These results suggest that Trigonellae Semen is an effective $ONOO^-$, $O_2^-$ and NO scavenger. and that this substance has a potential role as an inhibitor of the aging process, and in therapy against age-related diseases.

• The Journal of Internal Korean Medicine
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• v.30 no.1
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• pp.36-50
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• 2009

Objectives : This study was aimed to verify the cytoprotective function, antioxidative effect and inflammation genes inhibitory effects of Lycium chinense Milie. Therefore the generation of superoxide anion radical ( $O_2\;^-$), peroxynitrite ($ONOO^-$), nitric oxide (NO) and prostaglandin $E_2$ $(PGE_2)$ was investigated in the renal epithelial cells of mouse. Effects of Lycium chinense Milie on the expression of inflammation-related proteins, $IKK-{\alpha}$. $p-IKK-\alpha\beta$, $p-I{\kappa}B-\alpha$, $NF-{\kappa}B$ (p50, p65), COX-2 and iNOS, were examined by western blotting. Methods : For this study, the fluorescent probes were used, namely dihydrorhodamine 123 (DHR 123), 4.5-diaminofluorescein (DAF-2) and 2',7'-dichlorodihydrofluorescein diacetate (DCFDA). Western blotting was performed using anti-$IKK-\alpha$, anti-phospho $IKK-\alpha\beta$, anti-phospho $I{\kappa}B-\alpha$, anti-$NF-{\kappa}B$ (p50, p65), anti-COX-2 and anti-iNOS, respectively. Results : Lyciutn chinense Milie reduced $H_{2}O_{2}$-induced cell death dose-dependently. It inhibited the generation of $O_2\;^-$, $ONOO^-$, NO and $PGE_2$ in the $H_{2}O_{2}$-treated renal epithelial cells of mouse in vitro. Lycium chinense Milie inhibited the expression of $IKK-\alpha$, $p-IKK-\alpha\beta,\;p-I{\kappa}B-\alpha$, COX-2 and iNOS genes by means of decreasing activation of $NF-{\kappa}B$. Conclusions : According to above results. Lycium chinense Milie recommended to be applied in treatment for the inflammatory process and inflammation-related diseases.

• The Korean journal of internal medicine
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• v.34 no.1
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• pp.146-155
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• 2019

Background/Aims: Indoxyl sulfate (IS) is a uremic toxin and an important causative factor in the progression of chronic kidney disease. Recently, paricalcitol (19-nor-1,25-dihydroxyvitamin D2) was shown to exhibit protective effects in kidney injury. Here, we investigated the effects of paricalcitol treatment on IS-induced renal tubular injury. Methods: The fluorescent dye 2',7'-dichlorofluorescein diacetate was used to measure intracellular reactive oxygen species (ROS) following IS administration in human renal proximal tubular epithelial (HK-2) cells. The effects of IS on cell viability were determined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays and levels of apoptosis-related proteins (Bcl-2-associated protein X [Bax] and B-cell lymphoma 2 [Bcl-2]), nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) p65, and phosphorylation of mitogen-activated protein kinase (MAPK) and protein kinase B (Akt) were determined by semiquantitative immunoblotting. The promoter activity of $NF-{\kappa}B$ was measured by luciferase assays and apoptosis was determined by f low cytometry of cells stained with f luorescein isothiocyanate-conjugated Annexin V protein. Results: IS treatment increased ROS production, decreased cell viability and induced apoptosis in HK-2 cells. IS treatment increased the expression of apoptosis-related protein Bax, decreased Bcl-2 expression, and activated phosphorylation of MAPK, $NF-{\kappa}B$ p65, and Akt. In contrast, paricalcitol treatment decreased Bax expression, increased Bcl-2 expression, and inhibited phosphorylation of MAPK, $NF-{\kappa}B$ p65, and Akt in HK-2 cells. $NF-{\kappa}B$ promoter activity was increased following IS, administration and was counteracted by pretreatment with paricalcitol. Additionally, flow cytometry analysis revealed that IS-induced apoptosis was attenuated by paricalcitol treatment, which resulted in decreased numbers of fluorescein isothiocyanate-conjugated Annexin V positive cells. Conclusions: Treatment with paricalcitol inhibited IS-induced apoptosis by regulating MAPK, $NF-{\kappa}B$, and Akt signaling pathway in HK-2 cells.

• Molecules and Cells
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• v.44 no.9
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• pp.627-636
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• 2021

The three-dimensional organization of chromatin and its time-dependent changes greatly affect virtually every cellular function, especially DNA replication, genome maintenance, transcription regulation, and cell differentiation. Sequencing-based techniques such as ChIP-seq, ATAC-seq, and Hi-C provide abundant information on how genomic elements are coupled with regulatory proteins and functionally organized into hierarchical domains through their interactions. However, visualizing the time-dependent changes of such organization in individual cells remains challenging. Recent developments of CRISPR systems for site-specific fluorescent labeling of genomic loci have provided promising strategies for visualizing chromatin dynamics in live cells. However, there are several limiting factors, including background signals, off-target binding of CRISPR, and rapid photobleaching of the fluorophores, requiring a large number of target-bound CRISPR complexes to reliably distinguish the target-specific foci from the background. Various modifications have been engineered into the CRISPR system to enhance the signal-to-background ratio and signal longevity to detect target foci more reliably and efficiently, and to reduce the required target size. In this review, we comprehensively compare the performances of recently developed CRISPR designs for improved visualization of genomic loci in terms of the reliability of target detection, the ability to detect small repeat loci, and the allowed time of live tracking. Longer observation of genomic loci allows the detailed identification of the dynamic characteristics of chromatin. The diffusion properties of chromatin found in recent studies are reviewed, which provide suggestions for the underlying biological processes.