• Bulletin of the Korean Chemical Society
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• 제34권11호
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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.

• 정보과학회 컴퓨팅의 실제 논문지
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• 제22권1호
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• pp.20-25
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• 2016

디지털 빅데이터 시대가 도래함에 따라 다양한 분야에서 하둡 플랫폼이 널리 사용되고 있지만, 하둡 맵리듀스 프레임워크는 대량의 작은 파일들을 처리하는데 있어서 네임노드의 메인 메모리와 맵 태스크 수가 증가하는 문제점을 안고 있다. 또한, 맵리듀스 프레임워크에서 하드웨어 기반 데이터 병렬성을 지원하는 GPU를 활용하기 위해서는 C++ 언어 기반의 태스크를 맵리듀스 프레임워크에서 수행하기 위한 방식이 필요하다. 따라서, 본 논문에서는 이미지 빅데이터를 처리하기 위해 하둡 플랫폼 환경에서 이미지 시퀀스 파일을 생성하고 하둡 파이프를 이용하여 GPU 기반의 얼굴 검출 태스크를 맵리듀스 프레임워크에서 처리하는 얼굴 검출 시스템을 제시하고 단일 CPU 프로세스 대비 약 6.8배의 성능 향상을 보여준다.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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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.

• 한국전산구조공학회논문집
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• 제15권4호
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• pp.639-647
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• 2002

본 연구에서는 원주형 절취 독본(dogbonc) 내진 접합부 도입에 따른 철골모멘트골조의 횡강성 감소 정도를 용이하게 산정할 수 있는 실용적 해석기법을 제안하였다. 된 연구의 방안은 원래의 원주형 절취 형상의 독본에서 발생하는 신장량과 동일한 크기의 신장량이 유발되도록 등가의 균등한 유효폭을 갖는 독본 형상으로 치환하는 것에 근거하고 있다. 등가 유효폭을 도입하는 목적은 공액보법을 적용하여 보의 휨변형에 의한 골조의 횡변위 성분을 유도할 때 수행되는 전분을 해석적으로 하기 위함이다. 이러한 접근법의 타당성을 먼저 검증된 유한요소해석모델에 의해 확인한 후, 기둥, 패널존 그리고 보의 변형에서 기인하는 골조의 횡변위 성분을 독본의 존재를 고려하여 해석적으로 유도하였다. 이 유도결과를 이용한 사례분석에 의할 때, 독본의 도입에 따른 횡변위 증가율은 2%∼3%(횡강성 감소율로는 1%∼2%) 정도로서 실무적으로 무시할 수 있는 크기로 나타났다.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 추계학술발표회논문집(1)
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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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• 제16권9호
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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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• 제23권4호
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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.

• 한국식품과학회지
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• 제37권1호
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• pp.90-94
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• 2005

Quercetin을 50 및 100mg/kg의 용량으로 mouse에 경구투여 후 흡수, 대사 및 조직내 농도를 조사하였으며 일부의 시험은 비교를 위해 rat에서도 수행하였다. Quercetin은 mouse에서 신속히 흡수되어 l시간 후면 최고 혈장내 농도에 도달하였으며 4시간 후에는 현저하게 농도가 감소하였다. 주요 대사체인 isorhamnetin의 혈장내 농도도 신속하게 증가하였으나 quercetin 보다는 높은 농도로 유지되는 시간이 길었다. Rat에서 알려진 현상과 같이 quercetin이나 isorhamnetin 모두 유리상태로 존재하지 않고 대부분 glucuronide/sulfate의 포합체 형태로 존재하였다. Quercetin 및 isorhamnetin의 조직내 농도는 투여 1시간 및 6시간 콩히 간장>신장>비장>혈장의 순이었으며 이 순서는 rat에서도 마찬가지였다. 이 연구결과를 통해 mouse에서 quercetin이 경구투여 후 실제로 흡수되며 사람이나 다른 동물종에서 관찰된 것과 같이 quercetin은 신속하게 전환됨을 관찰하였다. 또한 이 결과는 mouse를 이용한 실험에서 지금까지 규명된 quercetin의 다양한 약리효과를 설명하는 데 필요한 자료의 역할을 할 수 있을 것이다.

• Archives of Pharmacal Research
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• 제27권6호
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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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• 제8권1호
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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.