Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 54 )

2018 ( 326 )

2017 ( 328 )

2016 ( 356 )

Custom range...

Search Results: 1 - 10 of 46314 matches for " Min-Sung Lee "
All listed articles are free for downloading (OA Articles)
Page 1 /46314
Display every page Item
Identification of a Novel Function of CX-4945 as a Splicing Regulator
Hyeongki Kim, Kwangman Choi, Hyunju Kang, So-Young Lee, Seung-Wook Chi, Min-Sung Lee, Jaehyoung Song, Donghwa Im, Yura Choi, Sungchan Cho
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0094978
Abstract: Alternative splicing is a nearly ubiquitous versatile process that controls gene expression and creates numerous protein isoforms with different functions from a single gene. The significance of alternative splicing has been confirmed by the increasing number of human diseases that are caused by misregulation of splicing events. Very few compounds, however, have been reported to act as inhibitors of alternative splicing, and their potential clinical use needs to be evaluated. Here, we report that CX-4945, a previously well-characterized inhibitor of casein kinase 2 (CK2) and a molecule currently in clinical trials (Phase II) for cancer treatment, regulates splicing in mammalian cells in a CK2-independent manner. Transcriptome-wide analysis using exon array also showed a widespread alteration in alternative splicing of numerous genes. We found that CX-4945 potently inhibits the Cdc2-like kinases (Clks) in vitro and in turn, leads to suppression of the phosphorylation of serine/arginine-rich (SR) proteins in mammalian cells. Surprisingly, the overall efficacy of CX-4945 on Clks (IC50 = 3–90 nM) was stronger than that of TG-003, the strongest inhibitor reported to date. Of the Clks, Clk2 was most strongly inhibited by CX-4945 in an ATP-competitive manner. Our research revealed an unexpected activity of the drug candidate CX-4945 as a potent splicing modulator and also suggested a potential application for therapy of diseases caused by abnormal splicing.
Biological Toxicity and Inflammatory Response of Semi-Single-Walled Carbon Nanotubes
Eun-Jung Park, Jinkyu Roh, Soo Nam Kim, Min-Sung Kang, Byoung-Seok Lee, Younghun Kim, Sangdun Choi
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0025892
Abstract: The toxicological studies on carbon nanotubes (CNTs) have been urgently needed from the emerging diverse applications of CNTs. Physicochemical properties such as shape, diameter, conductance, surface charge and surface chemistry of CNTs gained during manufacturing processes play a key role in the toxicity. In this study, we separated the semi-conductive components of SWCNTs (semi-SWCNTs) and evaluated the toxicity on days 1, 7, 14 and 28 after intratracheal instillation in order to determine the role of conductance. Exposure to semi-SWCNTs significantly increased the growth of mice and significantly decreased the relative ratio of brain weight to body weight. Recruitment of monocytes into the bloodstream increased in a time-dependent manner, and significant hematological changes were observed 28 days after exposure. In the bronchoalveolar lavage (BAL) fluid, secretion of Th2-type cytokines, particularly IL-10, was more predominant than Th1-type cytokines, and expression of regulated on activation normal T cell expressed and secreted (RANTES), p53, transforming growth factor (TGF)-β, and inducible nitric oxide synthase (iNOS) increased in a time-dependent manner. Fibrotic histopathological changes peaked on day 7 and decreased 14 days after exposure. Expression of cyclooxygenase-2 (COX-2), mesothelin, and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) also peaked on day 7, while that of TGF-β peaked on days 7 and 14. Secretion of histamine in BAL fluid decreased in a time-dependent manner. Consequently, we suggest that the brain is the target organ of semi-SWCNTs brought into the lung, and conductance as well as length may be critical factors affecting the intensity and duration of the inflammatory response following SWCNT exposure.
Advanced Burst Mode Control to Reduce the Standby Power of Flyback Converter  [PDF]
Min-Sung Kim, Hyoung-Woo Kim, Ji-Hye Jang, Ki-Hyun Kim
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.51B025
Abstract: This paper we proposed advanced burst mode control technique to reduce the standby power consumption of the switch mode power supply (SMPS). To reduce the standby power consumption, most of the converter use burst mode or skip mode control technique. However Conventional standby mode control techniques have some problems such as audible noise and poor regulation. In proposed techniques, basically, the burst mode control technique is employed to reduce the fundamental switching frequency while limiting the peak drain current. But, in proposed technique, to improve the regulation characteristic, burst period of the proposed technique is shorter than that of the conventional burst mode technique. And also, to reduce the switching loss increase due to the short burst period, burst switching signal of the proposed technique is partially skipped. By using proposed advanced burst mode control technique, calculated standby power is 0.695W while standby power of the conventional burst mode control is 1.014W.
Design of DC-DC Converter for Flash Memory IPs  [PDF]
Li-yan Jin, Woo-Young Jung, Ji-Hye Jang, Min-Sung Kim, Myeong-Seok Kim, Heon Park, Pan-Bong Ha, Young-Hee Kim
Engineering (ENG) , 2013, DOI: 10.4236/eng.2013.51B026
Abstract: A DC-DC converter for flash memory IPs performing erasing by the FN (Fowler-Nordheim) tunneling and programming by the CHEI (channel hot electron injection) is designed in this paper. For the DC-DC converter for flash memory IPs using a dual voltage of VDD (=1.5V±0.15V)/VRD (=3.1V±0.1V), a scheme of using VRD (Read Voltage) instead of VDD is proposed to reduce the pumping stages and pumping capacitances of its charge pump circuit. VRD (=3.1V±0.1V) is a regulated voltage by a voltage regulator with an external voltage of 5V, which is used as the WL activation voltage in the read mode and an input voltage of the charge pump. The designed DC-DC converter outputs positive voltages of VP6V (=6V), VP8V (=8V) and VP9V(=9V); and a negative voltage of  VM8V (=-8V) in the write mode.
Biological Responses to Diesel Exhaust Particles (DEPs) Depend on the Physicochemical Properties of the DEPs
Eun-Jung Park, Jinkyu Roh, Min-Sung Kang, Soo Nam Kim, Younghun Kim, Sangdun Choi
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0026749
Abstract: Diesel exhaust particles (DEPs) are the main components of ambient particulate materials, including polyaromatic hydrocarbons (PAHs), n-PAHs, heavy metals, and gaseous materials. Many epidemiological, clinical, and toxicological studies have shown that ambient particles, including DEPs, are associated with respiratory disorders, such as asthma, allergic rhinitis, and lung cancer. However, the relationship between the biological response to DEPs and their chemical composition remains unclear. In this study, we investigated the physicochemical properties of DEPs before toxicological studies, and then administered a single intratracheal instillation of DEPs to mice. The mice were then killed 1, 7, 14 and 28 days after DEP exposure to observe the biological responses induced by DEPs over time. Our findings suggest that DEPs engulfed into cells induced a Th2-type inflammatory response followed by DNA damage, whereas DEPs not engulfed into cells induced a Th1-type inflammatory response. Further, the physicochemical properties, including surface charge, particle size, and chemical composition, of DEPs play a crucial role in determining the biological responses to DEPs. Consequently, we suggest that the biological response to DEPs depend on cell-particle interaction and the physicochemical properties of the particles.
Dynamic Motile T Cells Highly Respond to the T Cell Stimulation via PI3K-Akt and NF-κB Pathways
Hye-Ran Kim, Bo-Ra Na, Min-Sung Kwon, Yoo-Seung Ko, Weon-Cheol Han, Chang-Duk Jun
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0059793
Abstract: T lymphocytes (T cells) circulate from the blood into secondary lymphoid organs for immune surveillance. In this study, we hypothesized that circulating T cells are heterogeneous and can be grouped according to their differential migratory capacity in response to chemoattractants, rather than expressions of certain receptors or cytokines. We further hypothesized that, at least in part, this intrinsic difference in motility may be related to the T cell function. We established motile (m-T) and non-motile T (nm-T) cell lines based on their response to the chemokine SDF-1α. m-T cells showed more irregular and polarized morphologies than nm-T cells did. Interestingly, m-T cells produced higher levels of IL-2, a marker for T cell activation, than nm-T cells did after stimulation; however, no differences were observed in terms of surface expression of T cell receptors (TCR), adhesion molecules LFA-1 and ICAM-1, and chemokine receptor CXCR4. Both cell lines also showed similar membrane events (i.e., T cell-APC conjugation, LFA-1 accumulation at the immunological synapse, and TCR internalization). In contrast, PKC-θ, a downstream of PI3K-Akt pathway was constitutively activated in m-T cells and the activation was more prominent during T cell stimulation. Consequently, NF-κB activity was selectively upregulated in m-T cells. This study is the first, to our knowledge, to demonstrate that T cells can be subcategorized on the basis of their intrinsic migratory capacity in relation to T cell activation.
Swiprosin-1 Is a Novel Actin Bundling Protein That Regulates Cell Spreading and Migration
Min-Sung Kwon, Kyoung Ryoung Park, Young-Dae Kim, Bo-Ra Na, Hye-Ran Kim, Hak-Jong Choi, Indre Piragyte, Hyesung Jeon, Kyung Hwun Chung, Woo Keun Song, Soo Hyun Eom, Chang-Duk Jun
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0071626
Abstract: Protein functions are often revealed by their localization to specialized cellular sites. Recent reports demonstrated that swiprosin-1 is found together with actin and actin-binding proteins in the cytoskeleton fraction of human mast cells and NK-like cells. However, direct evidence of whether swiprosin-1 regulates actin dynamics is currently lacking. We found that swiprosin-1 localizes to microvilli-like membrane protrusions and lamellipodia and exhibits actin-binding activity. Overexpression of swiprosin-1 enhanced lamellipodia formation and cell spreading. In contrast, swiprosin-1 knockdown showed reduced cell spreading and migration. Swiprosin-1 induced actin bundling in the presence of Ca2+, and deletion of the EF-hand motifs partially reduced bundling activity. Swiprosin-1 dimerized in the presence of Ca2+ via its coiled-coil domain, and a lysine (Lys)-rich region in the coiled-coil domain was essential for regulation of actin bundling. Consistent with these observations, mutations of the EF-hand motifs and coiled-coil region significantly reduced cell spreading and lamellipodia formation. We provide new evidence of how swiprosin-1 influences cytoskeleton reorganization and cell spreading.
Acute Calcific Tendinitis of the Flexor Digitorum Superficialis of the Finger: A Case Report  [PDF]
Young Sung Kim, Ho Min Lee, Jong Pil Kim
Open Journal of Orthopedics (OJO) , 2014, DOI: 10.4236/ojo.2014.43008
Abstract: Acute calcific tendinitis of the shoulder is a well-known condition, but it is rare in the hand or finger. It is often misdiagnosed when it occurs outside the shoulder. We report an unusual case of acute calcific tendinitis of the flexor digitorum superficialis insertion of the 4th finger in a young female martial art athlete after minor trauma history, and discuss with a review of the literature.
Aqueous Two Phase Extraction for the Recovery of 1,3-Propanediol from Its Aqueous Solutions  [PDF]
Min Hee Chung, Yeon Ki Hong, Hyoung Wook Lee, Sung-Jun Park
Advances in Materials Physics and Chemistry (AMPC) , 2012, DOI: 10.4236/ampc.2012.24B040
Abstract: As the biodiesel production is rapidly enhanced, the crude glycerol, which is by-product of biodiesel processes, is state of surplus. 1,3-PDO (1,3-propanediol), a valuable monomer of poly(trimethylene terephthalate) (PTT), can be produced from the fermentation process using crude glycerin as a carbon source. For the economic biological production of 1,3-PDO, the low cost and high efficient separation processes is essential. In this study, aqueous two-phase system composed of various hydrophilic alcohols and salt was used as a primary separation step for 1,3-PDO. It was found that the aqueous two-phase systems are easily formed with decreasing of the polarity of alcohols. The extraction efficiency is proportional to the polarity of alcohols. In case of methanol or ethanol/K2HPO4, the extraction efficiency was more than 90%.  It was concluded that the aqueous two-phase extraction using methanol or ethanol/K2HPO4 can be applied  for the primary separation of 1,3-PDO  as an alternative to a conventional primary separation processes.
Multipartite entanglement for entanglement teleportation
Jinhyoung Lee,Hyegeun Min,Sung Dahm Oh
Physics , 2002, DOI: 10.1103/PhysRevA.66.052318
Abstract: The scheme for entanglement teleportation is proposed to incorporate multipartite entanglement of four qubits as a quantum channel. Based on the invariance of entanglement teleportation under arbitrary two-qubit unitary transformation, we derive relations of separabilities for joint measurements at a sending station and for unitary operations at a receiving station. From the relations of separabilities it is found that an inseparable quantum channel always leads to a total teleportation of entanglement with an inseparable joint measurement and/or a nonlocal unitary operation.
Page 1 /46314
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.