• 한국자기공명학회논문지
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• 제20권1호
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• pp.17-21
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• 2016

Periostin, a component of extracellular matrix (ECM) protein, is produced and secreted by the fibroblasts that are involved in chronic allergic inflammation diseases and various types of human cancers. Periostin protein is composed of multiple domains including four FAS1 domains which play important roles in cell adhesion and tumor metastasis by interacting with integrins. In spite of their important biological role, the structural information of periosin FAS1 domains was not revealed yet. Recently we systemically prepared various constructs of the FAS1 domains and tried to express them in E. coli. Of them, only single FAS1-II and -IV domains were highly soluble. Circular dichroism (CD) and nuclear magnetic resonance (NMR) studies revealed that the FAS1-IV domain might be suitable for three-dimensional structure determination using NMR spectroscopy.

• 대한의용생체공학회:의공학회지
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• 제12권1호
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• pp.57-62
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• 1991

ABA type block copolymers composed of poly($\gamma-benzyl$ L-glutamate) (PBLG) as the A component and poly (ethylene glycol) as the B component were obtained by polymerization of $\gamma-benzyl$ L-gletamate N -carboxyanhydride, initiated by amino groups at both ends of poly(ethylene glycol) . From circular dichroism measurements in ethylene dichloride solution as well as from infrared spectTa measurements in solid state, it was found that the polypep- tide block exists in the a-helical conformation, as in PBLG homopolymer. $Poly-N^5$ (3-hydroxypropyl glutamine) (PHPG)/poly(ethylene glycol)block copolymer hydrogel was obtained by the treatment of PBLG/PBG block copolymer with the mixture of 3-ammine-1-propanol and diamlnooctane. The water content of PHPG/PEG block copolymer hydrogel was about 80wt% when the concentration of crosslinking agent was below 5 mole % per polymer.

• Journal of Pharmaceutical Investigation
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• 제15권1호
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• pp.15-21
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• 1985

The inclusion of ${\alpha}-cyclodextrin$ and ${\beta}-cyclodextrin$ with flurbiprofen in aqueous phase was investigated by UV absorption and circular dichroism spectroscopies. The inclusion complex in solid powder form were made by the freeze-drying and coprecipitation methods in molar ratio 1:1. The inclusion complex formation was confirmed by infrared absorption spectroscopy. The freeze-drying method was successful in obtaining the inclusion compounds compared with the coprecipitation method. The dissolution of solid flurbiprofen inclusion complex was examined in comparison with those of flurbiprofen alone. The inclusion complex obtained by freeze-drying method increased the dissolution rate.

• Journal of Applied Biological Chemistry
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• 제57권1호
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• pp.33-40
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• 2014

Polysaccharides have attracted great attention for their wide range of applications in biological and medical fields. In this paper, the interaction of polysaccharides with human serum albumin (HSA) was systematically investigated by fluorescence (FL) spectroscopy and circular dichroism (CD) spectra under different conditions. The Stern-Volmer quenching constants ($K_a$) at different ionic strength and pH were calculated, and information of the structural features of HSA was discussed. FL and CD results indicate that both hydrophobic and electrostatic interactions play important roles during the binding process. The quenching of the fluorescence resulting the binding of polysaccharides and HSA is static.

• 한국자기공명학회논문지
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• 제5권1호
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• pp.37-45
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• 2001

Synthetic pulmonary surfactants consisting of a mixture of phospholipids with synthetic peptides based on human surfactant-associated protein SP-B were prepared. These surfactants were analyzed f3r their secondary structures by circular dichroism (CD) spectroscopy and NMR spectroscopy. Two synthetic peptides (SP-B(3), SP-B(4)) combined with the phospholipid mixture displayed significant surfactant properties. The CD spectra showed that the u-helical propensities of the peptides in DPC micelles. In the NMR spectroscopy, the tertiary structures of SP-B(3) show that it has $\alpha$-helical structure from Gln5 to Arg13 in DPC micelle and SP-B(4) show that they have $\alpha$-helical structure from Gln5 to Leu12 in DPC micelle. Based on these structures, truncated peptides originated from SP-B protein, can be designed as effective synthetic surfactants for clinical use.

• Archives of Pharmacal Research
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• 제20권1호
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• pp.76-79
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• 1997

A new celastraceae alkaloid, euojaponine C has been isolated from the methanol extract of the root bark of Euonymus japonica. With the relative stereochemistry of euojaponine C established by NOESY data, the absolute stereochemistry has been determined by circular dichroism (CD) exciton chirality method. The CD of the 2, 5-bis-phenyl benzoate of triacetonide derived from the LiAlH$_{4}$, hydrolysate, euonyminol shows that the configuration of C-2 and C-5 are both R.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.241-241
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• 2006

Absolute configuration of carboxylic acids, including amino acids can be determined by circular dichroism (CD) exciton chirality method. This method employs cyclic oligopyrroles able to form stable complexes with carboxylic acids. Addition of carboxylic acids to the oligopyrroles induce CD spectrum at the macrocycle absorption region and in which the sign of the $1^{st}$ Cotton effect is determined solely by the absolute configuration of the carboxylic acid. The basicity of the pyrrole nitrogen can be controlled by macrocycle substitution thus yielding more sensitive chirality sensors.

• Macromolecular Research
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• 제15권6호
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• pp.575-580
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• 2007

Water-soluble, chiral conducting, poly(diphenylamine) (PDPA) nanocomposites were synthesized by chemical oxidative polymerization of diphenylamine in the presence of poly(acrylic acid) (PAA) as a template and camphor sulphonic acid (CSA) as the chiral inductor, Composites were formed as stable aqueous dispersions under different experimental conditions, such as DPA to PAA molar ratios, PAA molecular weight, etc. Circular dichroism(CD) spectra of the composites indicated the induction of chirality to PDPA. Compared to simple chiral PANI, the PDPA/PAA/CSA nanocomposites showed a different Cotton effect. The appearance of a CD band in the composite was complimentary to the bisignate, exciton-coupled band in the UV-Visible spectrum. FTIR spectra indicated the intimate mixing of PDPA and PAA.

• Journal of Magnetics
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• 제13권2호
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• pp.76-80
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• 2008

This study examined the magnetic properties of ultrathin Fe/Ni films on a Cu(001) surface using the full potential linearized augmented plane wave (FLAPW) method. The magnetic moment of Fe/Ni films was found to be insensitive to strain. Nevertheless, strain had a significant influence on the magnetization direction. For example, Fe/Ni films showed a thickness-dependent spin reorientation transition in the presence of strain, while the Fe/Ni films grown pseudomorphically on Cu(001) always showed perpendicular magnetization. In addition, the theoretically calculated X-ray magnetic circular dichroism (XMCD) was examined.

• 농업과학연구
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• 제37권3호
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• pp.543-545
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• 2010

Apo, holo, native-type of lactoferrin showed a similar pattern of circular dichroism(CD) spectra. Lactoferrin appeared to interact more easily with negatively charged liposome than neutral liposome. Holo-type of lactoferrin showed the highest degree of leakage, whereas apo-type of lactoferrin showed the lowest level of leakage. Holo-type lactoferrin could more easily interact with phospholipid liposomes than apo-type lactoferrin, when used as an artificial membrane.