• Bulletin of the Korean Chemical Society
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• v.34 no.11
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• pp.3243-3248
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• 2013

The tissue inhibitor of metalloproteinase-2 (TIMP-2) inhibits matrix metalloproteinases activity and modulates cellular proliferation and apoptosis. The human serum albumin-TIMP-2 with folic acid conjugate (termed HT2-folate) was synthesized to promote uptake through folate receptors (FRs), and a corresponding radio-labeled compound was prepared for tumor diagnosis by positron emission tomography (PET). $^{68}Ga$-NOTA-HT2-folate was synthesized from $^{68}Ga$ and the NOTA chelator with HT2-folate. The fusion protein was identified using MALDI-TOF mass spectrometry. The radioligand was prepared with a high radiochemical yield. Cell-surface association of $^{68}Ga$-NOTA-HT2-folate significantly increased over time in FR-positive tumor cells. In animal PET and biodistribution studies, tumor uptake was very high as early as 1 h after radioligand injection. Folate conjugation enhanced the selective receptor-targeting efficacy of HT2 in FRexpressing tumors, and its radioligand will be useful as an in vitro tool and for in vivo tumor diagnosis by PET imaging.

• KIISE Transactions on Computing Practices
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• v.22 no.1
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• pp.20-25
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• 2016

With the advent of the era of digital big data, the Hadoop platform has become widely used in various fields. However, the Hadoop MapReduce framework suffers from problems related to the increase of the name node's main memory and map tasks for the processing of large number of small files. In addition, a method for running C++-based tasks in the MapReduce framework is required in order to conjugate GPUs supporting hardware-based data parallelism in the MapReduce framework. Therefore, in this paper, we present a face detection system that generates a sequence file for images to process big data for images in the Hadoop platform. The system also deals with tasks for GPU-based face detection in the MapReduce framework using Hadoop Pipes. We demonstrate a performance increase of around 6.8-fold as compared to a single CPU process.

• Bulletin of the Korean Chemical Society
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• v.34 no.10
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• pp.2983-2988
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• 2013

Second-order rate constants ($k_N$) have been measured spectrophotometrically for the reactions of 4-chloro-2-nitrophenyl X-substituted-benzoates (1a-1h) with a series of cyclic secondary amines in 80 mol % $H_2O$/20 mol % DMSO at $25.0{\pm}0.1^{\circ}C$. The Hammett plot for the reactions of 1a-1h with piperidine consists of two intersecting straight lines, while the Yukawa-Tsuno plot exhibits an excellent linear correlation with ${\rho}_X $ = 1.25 and r = 0.58, indicating that the nonlinear Hammett plot is not due to a change in the rate-determining step (RDS) but is caused by ground-state stabilization through resonance interactions for substrates possessing an electron-withdrawing group in the benzoyl moiety. The Br${\o}$nsted-type plot for the reactions of 4-chloro-2-nitrophenyl benzoate (1d) with a series of cyclic secondary amines curves downward with ${\beta}_2$ = 0.85, ${\beta}_1$ = 0.24, and $pK_a{^o}$ = 10.5, implying that a change in RDS occurs from the $k_2$ step to the $k_1$ process as the $pK_a$ of the conjugate acid of the amine exceeds 10.5. Dissection of $k_N$ into the microscopic rate constants $k_1$ and $k_2/k_{-1}$ ratio associated with the reaction of 1d reveals that $k_2$ is dependent on the amine basicity, which is contrary to generally held views.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.4
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• pp.639-647
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• 2002

A simplified analytical procedure is presented to estimate the reduction of elastic lateral stiffness of steel moment frames arising from the radius-cut dogbone weakening. With the original radius-cut dogbone shape, it is almost impossible or too complicated to integrate analytically the mathematical expressions encountered when applying the conjugate beam method to compute the beam deflection component. In this study, the problem is circumvented by replacing the original radius-cut dogbone with an equivalent dogbone of constant width. The equivalence between the two is established by imposing an equal dogbone elongation criterion. This approach is justified by using a calibrated finite clement analysis. Then, the elastic lateral deflection components from the column, panel zone, and beam are derived for a typical beam-column subassembly. The derived results can be used to evaluate the reduction of the frame lateral stiffness. Case studies conducted within some practical ranges of frame configurations show that the reduction in frame lateral stiffness due to the presence of dogbone cut is on the order of 1 to 2 percent and is reasonably negligible in practical sense.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.719-725
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• 1997

This paper presents results of experimental studies on the heat transfer and solidification of the molten metal pool with overlying coolant with boiling. The metal pool is heated from the bottom surface and coolant is injected onto the molten metal pool. As a result, the crust, which is a solidified layer, may form at the top of the molten metal pool. Heat transfer is accomplished by a conjugate mechanism, which consists of the natural convection of the molten metal pool, the conduction in the crust layer and the convective boiling heat transfer in the coolant. This work examines the crust formation and the heat transfer rate on the molten metal pool with boiling coolant. The simulant molten pool material is tin (Sn) with the melting temperature of 232$^{\circ}C$. Demineralized water is used as the working coolant. The crust layer thickness was ostensibly varied by the heated bottom surface temperature of the test section, but not much affected by the coolant injection rate. The correlation beかeon the Nusselt number and the Rayleigh number in the molten metal Pool region of this study is compared against the crust formation experiment without coolant boiling and the literature correlations. The present experimental results are higher than those from the experiment without coolant boiling, but show general agreement with the Eckert correlation, with some deviations in the high and low ends of the Rayleigh number. This discrepancy is currently attributed to concurrent rapid boiling of the coolant on top of the metal layer.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1369-1376
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• 2006

Self-organized nanogels were prepared from pullulan/biotin conjugates (PU/Bio) for the development of an effective anticancer drug delivery system. The degree of biotin substitution was 11, 19, and 24 biotin groups per 100 anhydroglucose units of pullulan. The physicochemical properties of the nanogels (PU/Bio1, 2 and 3) in aqueous media were characterized by dynamic light scattering, transmission electron microscopy, and fluorescence spectroscopy. The mean diameter of all the samples was less than 300 nm with a unimodal size distribution. The critical aggregation concentrations (CACs) of the nanoparticles in distilled water were $2.8{\times}10^{-2},\;1.6{\times}10^{-2}$, and $0.7{\times}10^{-2}mg/ml$ for the PU/Bio1, 2, and 3, respectively. The aggregation behavior of the nanogels indicated that biotin can perform as a hydrophobic moiety. To observe the specific interaction with a hepatic carcinoma cell line (HepG2), the conjugates were labeled with rhodamine B isothiocyanate (RITC) and their intensities measured using a fluorescence microplate reader. The HepG2 cells treated with the fluorescence-labeled PU/Bio nanoparticles were strongly luminated compared with the control (pullulan). Confocal laser microscopy also confirmed internalization of the PU/Bio nanogels into the cancer cells. Such results demonstrated that the biotin in the conjugate acted as both a hydrophobic moiety for self-assembly and a tumor-targeting moiety for specific interaction with tumor cells. Consequently, PU/Bio nanogels would appear to be a useful drug carrier for the treatment of liver cancer.

• Journal of Microbiology and Biotechnology
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• v.23 no.4
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• pp.527-533
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• 2013

Polyclonal antibodies labeled with a tracer have been commonly used as secondary antibodies in immunochemical assays to quantify the concentration of antibody-antigen complexes. The majority of these antibodies conjugated with a tracer are commercially available, with the exception of few untouched targets. This study focused on the production and application of mouse anti-quail IgY as an intermediate antibody to link between quail egg yolk IgY and goat anti-mouse IgG-HRP as primary and secondary antibodies, respectively. Subsequently, the produced mouse anti-quail IgY was labeled with horseradish peroxidase (HRP) and its efficiency on enzyme linked immunosorbent assay (ELISA) was compared with that of commercial rabbit anti-chicken IgY-HRP. As an intermediate antibody, mouse anti-quail IgY was successfully produced with good affinity and sensitivity (1:10,000) to the primary and secondary antibodies. Subsequently, mouse anti-quail IgY was effectively conjugated with HRP enzyme, resulting in a secondary antibody with good sensitivity (1:10,000) to quail anti-V. parahaemolyticus and V. vulnificus IgY. The detection limit was $10^5$ CFU/ml for both V. parahaemolyticus and V. vulnificus. The efficiency of the produced conjugate to detect quail IgY on ELISA was comparable to that of the commercial rabbit anti-chicken IgY-HRP, and hence the produced and labeled mouse anti-quail IgY-HRP can be used as a secondary antibody to detect any antibody produced in quail.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.90-94
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• 2005

Absorption, metabolism, and tissue concentrations of quercetin were examined and compared in mice and rats after oral administration of quercetin at 50 or 100 mg/kg. Quercetin was absorbed quickly in mice and reached maximum plasma concentration in I hr post-administration, and declined sharply after 4 hr. Plasma concentration of isorhamnetin, a major metabolite, also increased sharply, indicating rapid metabolic conversion, but elevated level was maintained longer than that of quercetin. Quercetin and isorhamnetin were found predominantly in glucuronide/sulfate-conjugate forms in both mice and rats. Tissue concentrations of quercetin and isorhamnetin in mice and rats were in the order of liver>kidney>spleen>plasma both 1 and 6 hr postadministration. These results show that quercetin is absorbed in mice after oral feeding and quickly metabolized into isorhamnetin as demonstrated in humans and other animal species. The results also can be used to explain various pharmacological activities reported in mouse models.

• Archives of Pharmacal Research
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• v.27 no.6
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• pp.662-669
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• 2004

The highly water-soluble monomethoxypoly(ethyleneglycol) (mPEG) prod rugs of cyciosporin A(CsA) were synthesized. These prod rugs were prepared by initially preparing intermediate in the form of carbonate at the 3'-positions of CsA with chloromethyl chloroformate, in the pres-ence of a base to provide a 3'-carbonated CsA intermediate. Reaction of the CsA intermediate with mPEG derivative in the presence of a base provides the desired water-soluble prod rugs. As a model, we chose molecular weight 5 kDa mPEG in the reaction with CsA to give water soluble prodrugs. To prove that the prod rug is decomposed in the body to produce CsA, the enzymatic hydrolysis test was conducted using human liver homogenate at $37^{\circ}C$. The prodrug was decomposed in human liver homogenate to produce the active material, CsA, and the hydrolysis half-life ($t_{1/2}$) of the prodrug, KI-306 was 2.2 minutes at $37^{\circ}C$. However, a demon-stration of non-enzymatic conversion in pH 7.4 phosphate buffer was provided by the fact that the half-life ($t_{1/2}$) is 21 hours at 37$^{\circ}C$. The hydrolysis test in rat whole blood was also conducted. The hydrolysis was seen with half-life ($t_{1/2}$) of about 9.9, 65.0, 14.2, 3.4, 2.1 9.5, and 1.6 minutes for KI-306, 309, 312, 313, 315, 316, and 317, respectively. This is the ideal for CsA prodrug. The pharmacokinetic study of the prodrug, KI-306, in comparison to the commer-cial product (Sandimmune Neoral Solution) was also carried out after single oral dose. Each rat received 7 mg／kg of CsA equivalent dose. Especially, the prodrug KI-306 exhibits higher AUC and $C_{max}$ than the conventional Neoral. The AUC and $C_{max}$ were increased nearly 1.5 fold. The kinetic value was also seen with $T_{max}$ of about 1.43 and 2.44 hours for KI-306 and Neoral, respectively.

• Journal of Electrochemical Science and Technology
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• v.8 no.1
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• pp.43-52
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• 2017

In this paper, for the first time, the electroanalytical study of Triethylenediamine, TEDA was done on a typically graphene modified carbon paste electrode (Gr/CPE) in pH=10.5 of phosphate buffer solutions (PBS). The surface morphology of the bare and modified electrodes was characterized by scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The electro-oxidation of TEDA was investigated at the surface of modified electrode. The results revealed that the oxidation peak current of TEDA at the surface of Gr/CPE is 2.70 times than that shown at bare-CPE. A linear calibration plot was observed in the range of 1.0 to 202.0 ppm. In this way, the detection limit was found to be 0.18 ppm. The method was then successfully applied to determination of TEDA in aqueous samples obtained from two kinds of activated carbon from the masks of war. On the other hand, density functional theory (DFT) method at B3LYP/6-311++G** level of theory and a conductor-like Polarizable Continuum Model (CPCM) was used to calculate the $pK_a$ values of TEDA. The energies of lowest unoccupied molecular orbital ($E_{LUMO}$) and highest occupied molecular orbital ($E_{HOMO}$), gap energy (${\Delta}E$) and some thermodynamic parameters such as Gibbs free energy of TEDA and its conjugate acid ($HT^+$) were calculated. The results of calculated $pK_a$ were found to be in good agreement with the experimental values.