Lin M.M.,Tsinghua University |
Kim D.K.,Jungwon University
Journal of Nanoparticle Research | Year: 2012
A novel strategy for the fabrication of nanostructured materials based on preparation of metallic surfactants is presented and some examples are demonstrated in this article. The suggested synthetic procedure of metal oleate is universal, potentially able to produce bulk quantities, and can be applicable to the synthesis of other metal oxide and metal nanoparticles. In general, organometallic compounds are quite expensive and are mostly classified as a highly toxic substance. In this study, we used simple, inexpensive, and eco-friendly approaches to prepare the metallic surfactants. As an example, non-hydrated iron oleate (FeOl) complexes are prepared as precursors for the in situ-fabricated superparamagnetic iron oxide nanoparticles (SPIONs) by thermolysis. The different coordination of the non-hydrated FeOl complexes are directly relating to the competition between nucleation and crystal growth. The in situ preparation of SPIONs involves the reaction of metal nitrate and carboxylic acid at 120 ° C to synthesize the non-hydrated FeOl complexes and following the thermolysis of FeOl at 300 ° C in non-coordination solvent. The coordination modes and distinct thermal behaviors of intermediates non-hydrated FeOl complexes are comparatively investigated by means of thermo-analytic techniques complimented by differential scanning calorimetry, thermal gravimetric analysis (TGA) and infrared spectroscopy (FTIR). The potential chemical structures of non-hydrated FeOl and their reaction mechanism by thermolysis were elucidated. The resulting lipid-coated SPIONs were characterized by transmission electron microscope, FTIR, differential temperature analysis, and TGA. These data suggested a bimodal interaction of organic shell and nanoparticle surface, with chemically absorbed inner layer and physically absorbed outer layer of carboxylic acid. © Springer Science+Business Media B.V. 2012.
Choi H.K.,Jungwon University |
Lee K.,Dongguk University
Archives of Pharmacal Research | Year: 2012
Heat shock protein 90 (Hsp90) plays a critical role in the maintenance of multiple oncogenic pathways and is a required protein for folding and stability of many oncoproteins that are related to the growth, proliferation, and survival of many kinds of cancers. Ganetespib (STA-9090) is a potent, synthetic, small molecule inhibitor of Hsp90, and its binding to Hsp90 is known to result in the degradation of its client proteins and subsequent death of cancer cells. This article provides a review of ganetespib as one of the leading Hsp90 inhibitors, which is under investigation in a broad range of clinical stages for the treatment of cancer. © 2012 The Pharmaceutical Society of Korea and Springer Science+Business Media Dordrecht.
Yoon Y.G.,Jungwon University |
Koob M.D.,University of Minnesota
Pharmaceutical Research | Year: 2012
Purpose: We have previously shown that DNA constructs can be introduced into isolated mitochondria through the process of conjugative transfer from an E. coli host. We set out to generate a conjugative E. coli strain that would be able to introduce itself into the cytoplasm of a mammalian cell for the purpose of transferring DNA into the mitochondria in the cell. Methods: We have now developed a method for making E. coli strains from which nonreplicating populations of daughter cells can be generated. We used this approach to modify a facultative intracellular enteroinvasive E. coli (EIEC) and introduced conjugative functions to this new strain. Results: We demonstrate that this new strain can generate large populations of nonreplicating cells that are capable of conjugative transfer to other cells and can readily invade mammalian tissue culture cells, live in the cytoplasm of the cell for several days, and that do not kill the invaded mammalian cell. Conclusions: We successfully constructed an E. coli host suitable for intracellular conjugative transfer but, due to the lack of suitable mitochondrial screening or selectable markers, we have not yet been able to determine if these bacterial vectors can in fact transfer DNA into intracelluar mitochondria. © Springer Science+Business Media, LLC 2012.
Lee J.-W.,Jungwon University |
Lim S.,Seoul National University
Journal of Cosmology and Astroparticle Physics | Year: 2010
Many problems of cold dark matter models such as the cusp problem and the missing satellite problem can be alleviated, if galactic halo dark matter particles are ultra-light scalar particles and in Bose-Einstein condensate (BEC), thanks to a characteristic length scale of the particles. We show that this finite length scale of the dark matter can also explain the recently observed common central mass of the Milky Way satellites ( ∼ 10 7M⊙) independent of their luminosity, if the mass of the dark matter particle is about 10-22eV. © 2010 IOP Publishing Ltd and SISSA.
Lee J.-W.,Jungwon University
Journal of the Korean Physical Society | Year: 2013
The first law of thermodynamics and the holographic principle applied to an arbitrary large cosmic causal horizon are shown to naturally demand a zero cosmological constant and a non-zero dynamical dark energy in the form of the holographic dark energy. A semiclassical analysis shows that the holographic dark energy has a parameter d = 1 and an equation of state comparable to current observational data if the entropy of the horizon saturates the Bekenstein-Hawking bound. This result indicates that quantum field theory should be modified on a large scale to explain the dark energy. The relations among the dark energy, the quantum vacuum energy and the entropic gravity are also discussed. © 2013 The Korean Physical Society.
Lee J.-W.,Jungwon University
Foundations of Physics | Year: 2011
It is suggested that quantum mechanics is not fundamental but emerges from classical information theory applied to causal horizons. The path integral quantization and quantum randomness can be derived by considering information loss of fields or particles crossing Rindler horizons for accelerating observers. This implies that information is one of the fundamental roots of all physical phenomena. The connection between this theory and Verlinde's entropic gravity theory is also investigated. © 2010 Springer Science+Business Media, LLC.
Kim H.-S.,Jungwon University
Biotechnology Letters | Year: 2016
Objective: To identify a novel gene responsible for organic solvent-tolerance by screening a transposon-mediated deletion mutant library based on Saccharomyces cerevisiae L3262. Results: One strain tolerant of up to 0.5 % (v/v) n-hexane and cyclohexane was isolated. The determination of transposon insertion site identified one gene, YLR162W, and revealed disruption of the ORF of this gene, indicating that organic solvent tolerance can be conferred. Such a tolerant phenotype reverted to the sensitive phenotype on the autologous or overexpression of this gene. This transposon mutant grew faster than the control strain when cultured at 30 °C in YPD medium containing 0.5 % (v/v) n-hexane and cyclohexane respectively. Conclusion: Disruption of YLR162W in S. cerevisiae results in increased tolerance to organic solvents. © 2016 Springer Science+Business Media Dordrecht
Kim B.,Ellead Co. |
Choi Y.-E.,Chonbuk National University |
Kim H.-S.,Jungwon University
Phytotherapy Research | Year: 2014
Atopic dermatitis,which is related to dermatologic disorders and is associatedwith skin barrier dysfunction, represents an epidemic problem demanding effective therapeutic strategies. In the present study, we showed that the treatment with Eruca sativa extract resulted in a significant increase in the transactivation activity of peroxisome proliferator-activated receptor (PPAR) response element such as PPAR-α and suppression in the expression of inflammatory cytokine and antimicrobial peptides. In addition, E. sativa extract promotes the expression of filaggrin related to skin barrier protection. Quercetin and isorhamnetin, flavonoids' constituents of E. sativa, also promoted PPAR-α activity. These results indicate that E. sativa extract may be an appropriate material for improving skin barrier function as a skin therapeutic agent for atopic dermatitis. Copyright © 2014 John Wiley & Sons, Ltd.
Lee J.-W.,Jungwon University
Foundations of Physics | Year: 2012
It was recently suggested that quantum field theory is not fundamental but emerges from the loss of phase space information about matter crossing causal horizons. Possible connections between this formalism and Verlinde's entropic gravity and Jacobson's thermodynamic gravity are proposed. The holographic screen in Verlinde's formalism can be identified as local Rindler horizons and its entropy as that of the bulk fields beyond the horizons. This naturally resolves some issues on entropic gravity. The quantum fluctuation of the fields is the origin of the thermodynamic nature of entropic gravity. It is also suggested that inertia is related to dragging Rindler horizons. © 2012 Springer Science+Business Media, LLC.
Jungwon University | Date: 2015-05-28
A read/write cache device and method persistent in the event of a power failure are disclosed herein. The read/write cache device includes a meta-information part, a recency/frequency (RF) table part, a mapping table part, and a log area. The meta-information part provides information about whether metadata has integrity and information about the version of metadata stored in two metadata regions. The RF table part provides information about the recency and frequency of each of low-speed segments of a plurality of high-speed and low-speed segments and information about whether each of the low-speed segments is cached, in order to maintain the consistency of the metadata. The mapping table part provides information about a low-speed segment that is cached to each of the high-speed segments. The log area provides changed caching information that is not applied into the mapping table part.