Yongseok Choi

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Here, we designed a new nano-sized siRNA carrier system composed of biocompatible/biodegradable glycol chitosan polymer (GC) and strongly positively charged polyethylenimine (PEI) polymers. In order to make a stable and tumor-homing nano-sized carrier, each polymer was modified with hydrophobic 5beta-cholanic acid, and they were simply mixed to form(More)
This study reports that tumor-targeting glycol chitosan nanoparticles with physically loaded and chemically conjugated photosensitizers can be used in photodynamic therapy (PDT). First, the hydrophobic photosensitizer, chlorin e6 (Ce6), was physically loaded onto the hydrophobically-modified glycol chitosan nanoparticles (HGC), which were prepared by(More)
The condensed version: Thiolated glycol chitosan can form stable nanoparticles with polymerized siRNAs through charge-charge interactions and self-cross-linking (see scheme). This poly-siRNA/glycol chitosan nanoparticles (psi-TGC) provided sufficient in vivo stability for systemic delivery of siRNAs. Knockdown of tumor proteins by psi-TGC resulted in a(More)
In HEVC, the effect of the RDO on compression efficiency increases while its computational complexity accounts for an important part of the computation burden. For H.264/AVC, zero block (ZB) detection has been used as an efficient scheme to reduce the complexity of RDO operations. For HEVC, ZB detection is different from the scheme for H.264/AVC because(More)
Herein, we developed the photosensitizer, protoporphyrin IX (PpIX), conjugated glycol chitosan (GC) nanoparticles (PpIX-GC-NPs) as tumor-homing drug carriers with cellular on/off system for photodynamic imaging and therapy, simultaneously. In order to prepare PpIX-GC-NPs, hydrophobic PpIXs were chemically conjugated to GC polymer and the amphiphilic PpIX-GC(More)
A new in-loop filter, sample adaptive offset (SAO) allows the latest video compression standard, HEVC or H.265, to achieve higher coding efficiency both in objective and subjective measures. However, it requires additional operations to estimate the best SAO parameters per coding tree unit (CTU) during the video encoding process, which often leads to many(More)
In light of the anti-inflammatory properties of histone deacetylase (HDAC) inhibitors, such as suberoylanilide hydroxamic acid (SAHA) and trichostatin A (TSA), we examined a new HDAC inhibitor KBH-A42 for its anti-inflammatory activities. KBH-A42 showed noteworthy anti-inflammatory properties in vitro via suppression of the production of TNF-alpha, a(More)
Preference for the northern (N) ring conformation of the ribose moiety of adenine nucleotide 3',5'-bisphosphate antagonists of P2Y(1) receptors was established by using a ring-constrained methanocarba (a bicyclo[3.1.0]hexane) ring as a ribose substitute (Nandanan et al. J. Med. Chem. 2000, 43, 829-842). We have now combined the ring-constrained(More)