새로운 구조의 fiber Fabry-Perot filter를 사용한 파장가변 단일방향 EDF ring 레이저

이희철,조성진,김용평,예윤해 경희대학교 레이저공학연구소 2001 레이저공학 Vol.12 No.-

We made the tunable unidirectional Er-doped fiber(EDF) ring laser by using new fiber Fabry-Perot(FP) filter. Filter has been built with simple construction, with does not require any additional aligning and beam-confining components for the reduction of the diffraction. Fiber FP tunable filter whose free spectral range and finess is 60 nm and 500 respectively. Wavelength tunable range over 60 nm(1520-1580nm) has been achieved.

Molocular Imaging and Nanomedicine(Biotechnology) : Three-dimensional morphometry of hepatic microvasculature in normal and CCl4-treated Liver using synchrotron x-ray tomography

( Yae Jin Yoon ),( Soeun Chang ),( Kyung Seo Park ),( Kyoung Ho Choi ),( Yoon Keun Kim ),( Jung Ho Je ),( Yong Song Gho ) 한국생화학분자생물학회 (구 한국생화학회) 2008 생화학분자생물학회 춘계학술발표논문집 Vol.2008 No.-

2′-hydroxycinnamaldehyde inhibits cancer cell proliferation and tumor growth by targeting the pyruvate kinase M2

Yoon, Yae Jin,Kim, Young-Hwan,Jin, Yena,Chi, Seung-Wook,Moon, Jeong Hee,Han, Dong Cho,Kwon, Byoung-Mog Elsevier 2018 Cancer letters Vol.434 No.-

<P><B>Abstract</B></P> <P>It is reported that 2′-hydroxycinnamaldehyde (HCA), isolated from cinnamon, has anti-tumor effects through the modulation of multi-target molecules. In this study, we identified pyruvate kinase M2 (PKM2) as a direct target of HCA by use of biochemical methods including affinity chromatography, drug affinity responsive target stability, and cellular thermal shift assay. PKM2 is up-regulated in multiple cancer types and is considered as a potential target for cancer therapy. HCA binds directly to PKM2 and selectively decreases the phosphorylation of PKM2 at Tyr105, indicating a potential anti-proliferative effect on prostate cancer cells. As a PKM2 activator, HCA increases pyruvate kinase activity by promoting the tetrameric state of PKM2. However, HCA suppresses protein kinase activity of PKM2 by decreasing the phosphorylation at Tyr105. Moreover, this leads to a decrease of PKM2-mediated STAT3 phosphorylation at Tyr705 and a down-regulation of target genes, including MEK5 and cyclin D1. Furthermore, HCA suppresses tumor growth and the release of tumor extracellular vesicles <I>in vivo</I> by inhibiting the phosphorylation of PKM2. Collectively, our results suggest that HCA may be a potential anticancer agent targeting PKM2 in cancer progression.</P> <P><B>Highlights</B></P> <P> <UL> <LI> HCA inhibits proliferation of DU145 prostate cancer cells and suppresses their growth in a xenograft mouse model. </LI> <LI> HCA directly binds to PKM2 in cancer cells and tumor tissues. </LI> <LI> HCA increases pyruvate kinase activity by promoting the tetrameric state of PKM2. </LI> <LI> HCA suppresses the release of tumor extracellular vesicles (EV) by dephosphorylating PKM2. </LI> </UL> </P>

Benproperine, an ARPC2 inhibitor, suppresses cancer cell migration and tumor metastasis

Yoon, Yae Jin,Han, Young-Min,Choi, Jiyeon,Lee, Yu-Jin,Yun, Jieun,Lee, Su-Kyung,Lee, Chang Woo,Kang, Jong Soon,Chi, Seung-Wook,Moon, Jeong Hee,Lee, Sangku,Han, Dong Cho,Kwon, Byoung-Mog Elsevier 2019 Biochemical pharmacology Vol.163 No.-

<P><B>Abstract</B></P> <P>Metastasis is the leading cause of cancer mortality and cancer cell migration is an essential stage of metastasis. We identified benproperine (Benp, a clinically used antitussive drug) as an inhibitor of cancer cell migration and an anti-metastatic agent. Benp selectively inhibited cancer cell migration and invasion, which also suppressed metastasis of cancer cells in animal models. Actin-related protein 2/3 complex subunit 2 (ARPC2) was identified as a molecular target of Benp by affinity column chromatography with Benp-tagged Sepharose beads. Benp bound directly to ARPC2 in cells, which was validated by pull-down assay using Benp-biotin and label-free biochemical methods such as the drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA). Benp inhibited Arp2/3 function, showing disruption of lamellipodial structure and inhibition of actin polymerization. Unlike Arp2/3 inhibitors, Benp selectively inhibited the migration of cancer cells but not normal cells. ARPC2-knockdown cancer cells showed defective cell migration and suppressed metastasis in an animal model. Therefore, ARPC2 is a potential target for anti-metastatic therapy, and Benp has the clinical potential to block metastasis. Furthermore, Benp is a useful agent for studying the functions of the Arp2/3 complex in cancer cell migration and metastasis.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

2′‐Hydroxycinnamaldehyde inhibits proliferation and induces apoptosis via signal transducer and activator of transcription 3 inactivation and reactive oxygen species generation

Yoon, Yae Jin,Kim, Young‐,Hwan,Lee, Yu‐,Jin,Choi, Jiyeon,Kim, Cheol‐,Hee,Han, Dong Cho,Kwon, Byoung‐,Mog John Wiley and Sons Inc. 2019 CANCER SCIENCE Vol.110 No.1

<P>Inhibition of the signal transducer and activator of transcription 3 (STAT3) signaling pathway is a novel therapeutic strategy to treat human cancers with constitutively active STAT3. During the screening of natural products to find STAT3 inhibitors, we identified 2′‐hydroxycinnamaldehyde (HCA) as a STAT3 inhibitor, which was isolated from the stem bark of <I>Cinnamomum cassia</I>. In this study, we found that HCA inhibited constitutive and inducible STAT3 activation in STAT3‐activated DU145 prostate cancer cells. HCA selectively inhibited the STAT3 activity by direct binding to STAT3, which was confirmed by biochemical methods, including a pull‐down assay with biotin‐conjugated HCA, a drug affinity responsive target stability (DARTS) experiment and a cellular thermal shift assay (CETSA). HCA inhibited STAT3 phosphorylation at the tyrosine 705 residue, dimer formation, and nuclear translocation in DU145 cells, which led to a downregulation of STAT3 target genes. The downregulation of cell cycle progression and antiapoptosis‐related gene expression by HCA induced the accumulation of cells in the G0/G1 phase of the cell cycle and then induced apoptosis. We also found that reactive oxygen species (ROS) were involved in the HCA‐induced inhibition of STAT3 activation and cell proliferation because the suppressed p‐STAT3 level was rescued by glutathione or N‐acetyl‐L‐cysteine treatment, which are general ROS inhibitors. These results suggest that HCA could be a potent anticancer agent targeting STAT3‐activated tumor cells.</P>

Extracellular vesicles as emerging intercellular communicasomes

( Yae Jin Yoon ),( Oh Youn Kim ),( Yong Song Gho ) 생화학분자생물학회(구 한국생화학분자생물학회) 2014 BMB Reports Vol.47 No.10

All living cells release extracellular vesicles having pleiotropic functions in intercellular communication. Mammalian extracellular vesicles, also known as exosomes and microvesicles, are spherical bilayered proteolipids composed of various bioactive molecules, including RNAs, DNAs, proteins, and lipids. Extracellular vesicles directly and indirectly control a diverse range of biological processes by transferring membrane proteins, signaling molecules, mRNAs, and miRNAs, and activating receptors of recipient cells. The active interaction of extracellular vesicles with other cells regulates various physiological and pathological conditions, including cancer, infectious diseases, and neurodegenerative disorders. Recent developments in high-throughput proteomics, transcriptomics, and lipidomics tools have provided ample data on the common and specific components of various types of extracellular vesicles. These studies may contribute to the understanding of the molecular mechanism involved in vesicular cargo sorting and the biogenesis of extracellular vesicles, and, further, to the identification of disease-specific biomarkers. This review focuses on the components, functions, and therapeutic and diagnostic potential of extracellular vesicles under various pathophysiological conditions.

Geranylnaringenin (CG902) inhibits constitutive and inducible STAT3 activation through the activation of SHP-2 tyrosine phosphatase

Jin, Yena,Yoon, Yae Jin,Jeon, Yoon Jung,Choi, Jiyeon,Lee, Yu-Jin,Lee, Joonku,Choi, Sangho,Nash, Oyekanmi,Han, Dong Cho,Kwon, Byoung-Mog Pergamon Press 2017 Biochemical pharmacology Vol.142 No.-

<P><B>Abstract</B></P> <P>The roles and significance of signal transducer and activator of transcription 3 (STAT3) in human cancers have been extensively studied and STAT3 is a promising therapeutic target for cancer drug discovery. During the screening of natural products to identify STAT3 inhibitors, we identified geranylnaringenin (CG902), which decreased luciferase activity in a dose-dependent manner. CG902 specifically inhibited STAT3 phosphorylation at Tyr-705 in DU145 prostate cancer cells and decreased the expression levels of STAT3 target genes, such as cyclin D1, cyclin A, and survivin. Notably, the knockdown of the SHP-2 gene by small interfering RNA suppressed the ability of CG902 to inhibit STAT3 activation and CG902 activated the phosphatase activity of SHP-2 through direct interaction with SHP-2 and induced the phosphorylation of SHP-2. The interactions between CG902 and SHP-2 were confirmed by pull-down assay using biotinylated CG902. The interactions were also further validated by the drug affinity responsive target stability (DARTS) and cellular thermal shift assay (CETSA). The inhibitory effect of CG902 on cell growth was confirmed using the DU145 mouse xenograft model. We propose that CG902 inhibits STAT3 activity through a mechanism that involves the interactions between CG902 and SHP-2, and the phosphorylation of SHP-2, which leads to SHP-2 activation in DU145 cells. CG902 is the first compound to regulate STAT3 activity via the modulation of SHP-2 activity, and our results suggest that CG902 is a novel inhibitor of the STAT3 pathway and an activator of SHP-2, and may be a useful lead molecule for the development of a therapeutic STAT3 inhibitor.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Optimization of the Spatial Resolution for the GE Discovery PET/CT 710 by Using NEMA NU 2-2007 Standards

Hyun Jin Yoon,Young Jin Jeong,Hye Joo Son,Do-Young Kang,Kyung-Yae Hyun,Min-Kyung Lee 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.2

The spatial resolution in positron emission tomography (PET) is fundamentally limited by the geometryof the detector element, the positron’s recombination range with electrons, the acollinearityof the positron, the crystal decoding error, the penetration into the detector ring, and the reconstructionalgorithms. In this paper, optimized parameters are suggested to produce high-resolutionPET images by using an iterative reconstruction algorithm. A phantom with three point sourcesstructured with three capillary tubes was prepared with an axial extension of less than 1 mm andwas filled with 18F-fluorodeoxyglucose (18F-FDG) with concentrations above 200 MBq/cc. Theperformance measures of all the PET images were acquired according to the National ElectricalManufacturers Association (NEMA) NU 2-2007 standards procedures. The parameters for the iterativereconstruction were adjusted around the values recommended by General Electric GE, andthe optimized values of the spatial resolution and the full width at half maximum (FWHM) or thefull width at tenth of maximum (FWTM) values were found for the best PET resolution. Theaxial and the transverse spatial resolutions, according to the filtered back-projection (FBP) at 1cm off-axis, were 4.81 and 4.48 mm, respectively. The axial and the transaxial spatial resolutionsat 10 cm off-axis were 5.63 mm and 5.08 mm, respectively, and the trans-axial resolution at 10 cmwas evaluated as the average of the radial and the tangential measurements. The recommendedoptimized parameters of the spatial resolution according to the NEMA phantom for the numberof subsets, the number of iterations, and the Gaussian post-filter are 12, 3, and 3 mm for the iterativereconstruction VUE Point HD without the SharpIR algorithm (HD), and 12, 12, and 5.2mm with SharpIR (HD.S), respectively, according to the Advantage Workstation Volume Share 5(AW4.6). The performance measurements for the GE Discovery PET/CT 710 using the NEMANU 2-2007 standards from our results will be helpful in the quantitative analysis of PET scannerimages. The spatial resolution was modified more by using an improved algorithm such as HD.S,than by using HD and FBP. The use of the optimized parameters for iterative reconstructions isstrongly recommended for qualitative images from the GE Discovery PET/CT 710 scanner.

Viral Load Kinetics of SARS-CoV-2 Infection in First Two Patients in Korea

Jin Yong Kim,Jae-Hoon Ko,김예진,Yae-Jean Kim,Jeong-Min Kim,Yoon-Seok Chung,Heui Man Kim,Myung-Guk Han,So Yeon Kim,Bum Sik Chin 대한의학회 2020 Journal of Korean medical science Vol.35 No.7

As of February 2020, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak started in China in December 2019 has been spreading in many countries in the world. With the numbers of confirmed cases are increasing, information on the epidemiologic investigation and clinical manifestation have been accumulated. However, data on viral load kinetics in confirmed cases are lacking. Here, we present the viral load kinetics of the first two confirmed patients with mild to moderate illnesses in Korea in whom distinct viral load kinetics are shown. This report suggests that viral load kinetics of SARS-CoV-2 may be different from that of previously reported other coronavirus infections such as SARS-CoV.

Colorimetric evaluation of white spot lesions following external bleaching with fluoridation

Yoon-Young Choi,Dong-Yul Lee,Yae-Jin Kim 대한치과교정학회 2018 대한치과교정학회지 Vol.48 No.6

Objective: This study was performed to investigate the effects of external tooth bleaching with flouridation on the appearance of white spot lesions (WSLs) in vitro. Methods: In total, 125 bracket-bonded bovine incisor enamel blocks with artificial WSLs were randomly divided into a control group and four treatment groups (home bleaching, home bleaching + fluoridation, in-office bleaching, and in-office bleaching + fluoridation). A spectroradiometer (SR) and digital images (DIs) were used to evaluate colorimetric parameters (Commission Internationale l’Eclairage L*a*b*) for all specimens. Color measurements were obtained before WSL formation (T1), after WSL formation (T2), and after completion of the external tooth bleaching treatment (T3). Results: The SRbased color change after bleaching was significantly greater in the treatment groups than in the control group (p 〈 0.05). SR-based lightness (L*) and redgreen (a*) values were significantly higher at T2 than at T1 (p 〈 0.001), with no significant changes in yellow-blue (b*) values. At T3, SR-based L* values had increased while a* and b* values had decreased in the treatment groups (p 〈 0.001). The DI-based color difference between the sound enamel and WSL areas (DE*DI) increased significantly from T1 to T2 in all groups (p 〈 0.001) and significantly decreased from T2 to T3 in the treatment groups (p 〈 0.001). No significant differences in DE*DI at T3 were shown between the four treatment groups (p 〉 0.05). Conclusions: The findings of this study suggested that external tooth bleaching with fluoridation can alleviate the conspicuity of WSLs.