• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.179-186
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• 1997

The pharmacokinetics and tissue distribution of DWP20373, a novel fluoroquinolone, were examined in rats and beagle dogs after a single intravenous and oral administration. Analysis of DWP20373 in plasma, tissue, and urine was performed by both HPLC and microbiological assay. The plasma drug concentration declined biexponentially both rats and beagle dogs. In the rats, the terminal drug elimination half-life (t$_{1}$2$\beta$/) was 64 min (IV) and 57 min (PO) by bioassay, and 76 min (IV) and 77 min (PO) by HPLC. Whereas in beagle dogs, t$_{1}$2$\beta$/ was 196 min (IV) and 350 min (PO). The volume of distribution at steady-state (Vd$_{ss}$ ) was 811 ml/kg (bioassay) and 2061 ml/kg (HPLC) in rats, and 2738 ml/kg (bioassay) in beagle dogs. The total body clearance (Cl$_{t}$) of DWP20373 was 10 ml/min/kg (bioassay) and 7 ml/min/kg (HPLC) in rats, and 11 m1/min/kg (bioassay) in beagle dogs. The extent of bioavailability after oral administration was 49% (bioassay) and 67% (HPLC) in rats, and 84% (bioassay) in beagle dogs. The 24-h urinary recovery, measured by bioassay, was 2.7% after oral dosing and 5.5% after intravenous dosing in rats. Serum protein binding ratio determined at 27g/ml was 78%. This drug was also distributed in tissues in the decreasing order of liver, kidney, spleen, lung, heart, and muscle determined at 30 min after oral administration.on.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.260-260
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• 1994

Mammalian pyruvate dehydrogenase complex(PDC) enzyme consists of multiple oopies of three major oligomeric enzymes-El, E2 E3. And protein X is one of the enzymatic constituents which is tightly bound to E2 subunit This complex enzyme is responsible for the oxidative decarboxylation of pyruvate producing of acetyl CoA which is a key intermediate for the entry of carbohydrates into the TCA cycle for its complete metabolic conversion to CO$_2$. And the overall activity of the complex enzyme is regulated via covalent nodification of El subunit by a El specific phosphatase ad kinase. Protein X has lipoyl moiety that undergoes reduction and acetylation during ezymatic reaction and has been known h be involved in the binding of E3 subunit to E2 core and in the regulatory activity of kinase. The purification of protein X has not been achieved majorly because of its tight binding to E2 subunit The E2-protein X subcomplex was obtained by the established methods and the detachment of protein X from E2 was accomplished in the 0.1M borate buffer containing 150mM NaCl. During the storage of the subcomplex in frozen state at -70$^{\circ}C$, the E2 subunit was precipitated and the dissociated protein X was obtained by cntrifegation into the supernatant The verification of protein X was accomplished by (1)the migration on SDS-PAGE, (2)acetylation by 〔2$\^$-l4/C〕 pyruvate, and (3)internal amino acid sequence analysis of tryptic digested enzyme.

• The KIPS Transactions:PartC
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• v.13C no.2 s.105
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• pp.211-218
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• 2006

The Mobile IPv6 provides the enhanced internet services to user by supporting a node's mobility. In Mobile IPv6(MIPv6), the mobile node sends the binding message which binds home address(HoA) with care-of address(CoA) to the home agent whenever it changes its point of attachment to the internet. To reduce the mobility management signal message the Paging Hierarchical Mobile IPv6(PHMIPv6) is proposed. The mobile node does not send the binding message within the domain if the mobile node's state is idle. Therefore the mobility signal message cost can be reduced. However, when the mobile node's session arrival rate is high the many mobility management signal cost are needed because the paging cost is very high. In this paper, we analysis the drawback of PHMIPv6 and propose the scheme which can reduce the mobility management signal cost. The proposed scheme works independent of the number of subnet in the domain. Therefore the proposed scheme can improve the mobile node's mobility management scheme.

• YAKHAK HOEJI
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• v.41 no.3
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• pp.312-320
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• 1997

Pharmacokinetics and tissue distribution of DWP20349 and 20351, new quinolones, were examined in rats after a single intravenous and oral administration. Analyses of DWP20349 an d DWP20351 in plasma, tissue, and urine were determined by both HPLC and bioassay(microbiological assay). The plasma concentrations of the drugs declined biexponentially. The terminal half-lives ($t_{1/2\beta}$) of drugs were about 114 min (DWP20349) and 105 min (DWP20351) after intravenous dosing, and were 77 min (DWP20349) and 79 min (DWP20351) after oral dosing. The volume of distrbution at steady-state ($Vd_{ss}$) and total body clearances ($Cl_t$) of DWP20349 and DWP20351 were 760 ml/kg and 1126 ml/kg, and 5ml/min/kg and 10 ml/min/kg, respectively. The extents of bioavailability if DWP20349 and DWP20351 after oral administration were 29% and 28%, respectively. 24 h urinary recoveries measured by bioassay were 1.8% (DWP20349) and 1.3% (DWP20351) after oral dosing, and 2.4% (DWP20349) and 1.9% (DWP20351) after intravenous dosing. Plasma protein binding ratios ranged from 87%-90% (DWP20349) and 61%-68% (DWP20351). These drugs were highly distrbuted by the order of lung, kidney, liver and plasma (DWP20394), and lung, liver, kidney and plasma (DWP20351) after 1 hour orally administered.

• Bulletin of the Korean Chemical Society
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• v.31 no.8
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• pp.2170-2174
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• 2010

The surfaces of $TiO_2$ and ZnO nanoparticles have been modified by gold (Au) nanoparticles by a reduction method in solution. Their interfacial electronic structures and optical absorptions have been studied by depth-profiling X-ray photoelectron spectroscopy (XPS) and UV-vis absorption spectroscopy, respectively. Upon Au-modification, UV-vis absorption spectra reveal a broad surface plasmon peak at around 500 nm. For the as-prepared Au-modified $TiO_2$ and ZnO, the Au $4f_{7/2}$ XPS peaks exhibit at 83.7 and 83.9 eV, respectively. These are due to a charge transfer effect from the metal oxide support to the Au. For $TiO_2$, the larger binding energy shift from that (84.0 eV) of bulk Au could indicate that Au-modification site of $TiO_2$ is different from that of ZnO. On the basis of the XPS data with sputtering depth, we conclude that cationic (1+ and 3+) Au species, plausibly $Au(OH)_x$ (x = 1-3), commonly form mainly at the Au-$TiO_2$ and Au-ZnO interfaces. With $Ar^+$ ion sputtering, the oxidation state of Ti dramatically changes from 4+ to 3+ and 2+ while that (2+) of Zn shows no discernible change based on the binding energy position and the full-width at half maximum (FWHM).

• Journal of the Korean Chemical Society
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• v.50 no.3
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• pp.190-195
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• 2006

The critical micelle concentrations (CMC) and the counter ion binding constants (B) in a micellar state of the mixed surfactant systems of sodium dodecylbenzenesulfonate (DBS) with polyoxyethylene(4) lauryl ether (Brij 30) in water were determined as a function of 1 (the overall mole fraction of DBS) by the use of electric conductivity method and surface tensiometer method from 288 K to 308 K. Various thermodynamic parameters (Smo, Hmo, and Gmo) for the micellization of DBS/Brij 30 mixtures were calculated and analyzed from the temperature dependence of CMC values. The measured values of Gomare all negative but the values of Smo are positive in the whole measured temperature region. On the other hand, the values of Hmo are positive or negative, depending on the measured temperature and 1.

• Bulletin of the Korean Chemical Society
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• v.32 no.7
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• pp.2253-2259
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• 2011

The self-assembly of one novel organic complex based on chlorogenic acid (HCA) and 2,2'-bipyridine (2,2'-bipy) has been synthesized and characterized. The complex achieved by hydrogen-bonding interactions, adopted a 1:1 stoichiometry in a solid state. The proton transfer occurred from the carboxyl oxygen to the aromatic nitrogen atom to form salts CA${\cdot}$(2,2'-Hbipy), the 2,2'-Hbipy molecule individually occupies the pseudo-tetragonum that is formed with CA. In this paper, the interactions of CA${\cdot}$(2,2'-Hbipy) with bovine serum albumin (BSA) were studied by fluorescence spectrometry. For CA${\cdot}$(2,2'-Hbipy), HCA and 2,2'-bipy, the average quenching constants for BSA were $2.4384{\times}10^4$, $4.653{\times}10^3$, and $3.059{\times}10^3\;L{\cdot}mol^{-1}$, respectively. The mechanism for protein fluorescence quenching is apparently governed by a static quenching process. The Stern-Volmer quenching constants and corresponding thermodynamic parameters ${\Delta}$H, ${\Delta}$G and ${\Delta}$S were calculated. The binding constants and the number of binding sites were also investigated. The conformational changes of BSA were observed from synchronous fluorescence spectra.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.1
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• pp.51-55
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• 2016

Phytochemical investigation of Pistacia integerrima has highlighted isolation of two known compounds naringenin (1) and dihydrokaempferol (2). A crude extract and these isolated compounds were here evaluated for their effects on reversion of multidrug resistance (MDR) mediated by P-glycoprotein (P-gp). The multidrug resistance P-glycoprotein is a target for chemotherapeutic drugs from cancer cells. In the present study rhodamine-123 exclusion screening test on human mdr1 gene transfected mouse gene transfected L5178 and L5178Y mouse T-cell lymphoma cells showed excellent MDR reversing effects in a dose dependent manner. In-silico molecular docking investigations demonstrated a common binding site for Rhodamine123, and compounds naringenin and dihydrokaempferol. Our results showed that the relative docking energies estimated by docking softwares were in satisfactory correlation with the experimental activities. Preliminary interaction profile of P-gp docked complexes were also analysed in order to understand the nature of binding modes of these compounds. Our computational investigation suggested that the compounds interactions with the hydrophobic pocket of P-gp are mainly related to the inhibitory activity. Moreover this study s a platform for the discovery of novel natural compounds from herbal origin, as inhibitor molecules against the P-glycoprotein for the treatment of cancer.

• BMB Reports
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• v.34 no.5
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• pp.446-451
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• 2001

The interaction of cytochrome c with binary phospholipid mixtures was investigated by solid-state $^2H$- and $^{31}P$-NMR. To examine the effect of the interaction on the glycerol backbones, the glycerol moieties of phosphatidylcholine (PC), and cardioliph (CL) were specifically deuterated. On the binding of cytochrome c to the binary mixed bilayers, no changes in the quadrupole splittings of each of the components were observed for the PC/PG, PE/CL and PE/PG liposomes. In contrast, the splittings of CL decreased on binging of protein to the PC/CL liposomes, although those of PC did not change at all. This showed that cytochrome c specifically interacts with CL in PC/CL bilayers, and penetrates into the lipid bilayer to some extent so as to perturb the dynamic structure of the glycerol backbone. This is distinctly different from the mode of interaction of cytochrome c with other binary mixed bilayers. In the $^{31}P$-NMR spectra, line broadening and a decrease of the chemical shift anisotropy were observed on the binding of cytochrome c for all binary mixed bilayers that were examined. These changes were more significant for the PC/CL bilayers. Furthermore, the line broadening is more significant for PC than for CL in PC/CL bilayers. Therefore, it can be concluded that with the polar head groups, not only CL but also PC are involved in the interaction with cytochrome c.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.910-913
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• 2004

Insulin-like growth factor binding protein-3 (IGFBP-3) gene is a structural gene associated with the growth and development of the animals. The present investigation was carried out to unravel nucleotide sequence and polymerase chain reactionrestriction fragment polymorphism (PCR-RFLP) of IGFBP-3 gene in buffalo. Genomic DNA was isolated from a total of 157 animals belonging to Murrah, Surti, Jaffarabadi and Nagpuri breeds of Indian riverine buffalo. A 655 bp of IGFBP-3 gene was amplified in all the breeds and amplicons were digested with Hae III, Taq I and Msp I restriction enzymes. On digestion with Hae III yielded single restriction pattern of 8 fragments of sizes 201, 165, 154, 56, 36, 19, 16 and 8 bp in all the animals studied. Similarly Taq I and Msp I also revealed single restriction pattern yielding fragments of sizes 240 and 415 bp and 145 and 510 bp, respectively. This shows nonpolymorphic nature of restriction sites in buffalo. Nucleotide sequencing of 587 bp of IGFBP-3 gene in Murrah buffalo was done and submitted to the GenBank (Accession No. AY304829). Nucleotide sequencing revealed an addition of 4 bases in the intronic region as compared to cattle.