• Journal of Life Science
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• v.28 no.1
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• pp.99-104
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• 2018

Streptococcus pneumoniae is one of the major pathogens in community-acquired diseases, and it contains several factors that promote its pathogenesis, including pneumolysin (PLY). PLY is a member of the cholesterol-dependent cytolysin family, which attacks cholesterol-containing membranes, thereby forming ring-shaped pores. Thus, it is a major key target for vaccines against pneumococcal disease. We cloned the PLY gene from S. pneumoniae D39 and inserted it into the pQE-30 vector. Recombinant PLY (rPLY) was overexpressed in Escherichia coli M15 and purified by $Ni^{2+}$ affinity chromatography. Similarly, a PLY-EGFP fusion gene was produced by inserting the EGFP gene at the 3' end of the PLY gene in the same vector, and the recombinant protein was purified. Sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE) showed that both recombinant proteins were purified. rPLY exhibited significant hemolytic activity against 1% human red blood cells (RBCs). Complete hemolysis was obtained at 500 ng/ml, and 50% hemolysis was found with a 240 ng/ml concentration. In contrast, rPLY-EGFP did not show hemolytic activity. However, rPLY-EGFP did bind the RBC membrane, indicating that rPLY-EGFP lost hemolytic activity via EGFP fusion, while retaining its membrane-binding ability. These data suggest that PLY's C terminus is important for its hemolytic activity. Therefore, these two recombinant proteins can be extremely useful for investigating the toxin mechanism of PLY and cell damage during pneumonia.

• Journal of the Korea Society of Computer and Information
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• v.8 no.4
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• pp.92-103
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• 2003

Great many advertisements are serviced in on-line by development of electronic commerce and internet user's rapid increase recently. However, this advertisement service is stopping in one-side service of relevant advertisement rather than doing users' inclination analysis to basis. Therefore, want advertisement service that many websites are personalized for efficient service of relevant advertisement and service through relevant server's log analysis research and enforce. Take advantage of log data of local system that this treatise is not analysis of server log data and analyze user's Preference degree and inclination. Also, try to propose advertisement system personalized by making relevant site tributary category and give weight of relevant tributary. User's preference user preference which analysis is one part of cooperation fielder ring of web personalized techniques use information in visit site tributary and suppose internet user's action in visit number of times of relevant site and try inclination analysis of mixing form. Express user's preference degree by vector, and inclination analysis result uninterrupted data that simplicity application form is not regarded and techniques that propose inclination analysis change of data since with move data use and analyze newly and proposed so that can do continuous renewal and application as feedback Sikkim. Presented method that can choose advertisements of relevant tributary through this result and provide personalized advertisement service by applying process such as user inclination analysis in advertisement chosen.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3243-3254
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• 2013

It is well known that increased incidences of lung, skin, and bladder cancers are associated with occupational exposure to PAHs. Animal studies show that certain PAHs also can affect the hematopoietic and immune systems and can produce reproductive, neurologic, and developmental effects. As a consequence, several studies have been attempted to investigate the fate of PAHs in atmospheric environment during the past decades. However, there is still a lack of information in regard to the atmospheric concentration of PAHs during the "Bon Fire Night". In this study, twenty-three polycyclic aromatic hydrocarbons and twenty-eight aliphatics were identified and quantified in the $PM_{10}$ and vapour range in Birmingham ($27^{th}$ November 2001-$19^{th}$ January 2004). The measured concentrations of total particulate and vapour (P+V) PAHs were consistently higher at the BROS in both winter and summer. Arithmetic mean total (P+V) PAH concentrations were $51.04{\pm}47.62$ ng $m^{-3}$ and $22.30{\pm}19.18$ ng $m^{-3}$ at the Bristol Road Observatory Site (BROS) and Elms Road Observatory Site (EROS) respectively. In addition arithmetic mean total (P+V) B[a]P concentrations at the BROS were $0.47{\pm}0.39$ ng $m^{-3}$ which exceeded the EPAQS air quality standard of 0.25 ng $m^{-3}$. On the other hand, the arithmetic mean total (P+V) aliphatics were $81.80{\pm}69.58$ ng $m^{-3}$ and $48.00{\pm}35.38$ ng $m^{-3}$ at the BROS and EROS in that order. The lowest average of CPI and $C_{max}$ measured at the BROS supports the idea of traffic emissions being a principle source of SVOCs in an urban atmosphere. The annual trend of PAHs was investigated by using an independent t-test and oneway independent ANOVA analysis. Generally, there is no evidence of a significant decline of heavier MW PAHs from the two data sets, with only Ac, Fl, Ph, An, 2-MePh, 1+9-MePh, Fluo and B[b+j+k]F showing a statistically significant decline (p<0.05). A further attempt for statistical analysis had been conducted by dividing the data set into three groups (i.e. 2000, 2001-2002 and 2003-2004). For lighter MW compounds a significant level of decline was observed by using one-way independent ANOVA analysis. Since the annual mean of $O_3$ measured in Birmingham City Centre from 2001 to 2004 increased significantly (p<0.05), it may be possible to attribute the annul reduction of more volatile PAHs to the enhanced level of annual average $O_3$. By contrast, the heavier MW PAHs measured at the BROS did not show any significant annual reduction, implying the difficulties of 5- and 6-ring PAHs to be subject to photochemical decomposition. The deviation of SVOCs profile measured at the EROS was visually confirmed during the "Bonfire Night" festival closest to the $6^{th}$ November 2003. In this study, the atmospheric PAH concentrations were generally elevated on this day with concentrations of Fl, Ac, B[a]A, B[b+j+k]F, Ind and B[g,h,i]P being particularly high.

• Journal of the Korean Chemical Society
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• v.33 no.4
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• pp.366-370
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• 1989

A new macrocyclic ligand 1,15,18-triaza-3,4;12,13-dibenzo-5,8,11-cycloeicosane (NdienOdien$H_4$ = $N_3O_3$) has been synthesized and identified by element analysis, NMR and IR spectrophotometry. Stepwise protonation constants of ligand are determined by potentiometry in 95% methanol solution(I = 0.1 mol $dm^{-3}$, $Me_4$NCl). log $K_1$;log $K_2$;log $K_3$ = 9.1;8.1;3.6.The kinetics of the acid-promoted dissociation reactions of complex cations of nickel(II) and copper(III) with NdienOdien and NdienOen macrocyclic ligands having, respectively, 17 and 20 ring members, have been studied spectrophotometrically in HCl$O_4$ NaCl$O_4$ aqueous solutions. From the temperature effect on kinetic constant ($k_{obs}$), the parameters of activation(${\Delta}H^{\neq}$, ${\Delta}S^{\neq}$) of dissociation reaction for $ML^{2+}$ with $H^+$ ion have been determined. We have proposed the possible mechanism of the reaction from the data obtained.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.10a
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• pp.15-15
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• 1999

In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

• Biomolecules & Therapeutics
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• v.25 no.6
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• pp.578-585
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• 2017

Recently, there has been a rise in the number of amphetamine derivatives that serve as substitutes for controlled substances (e.g. amphetamine and methamphetamine) on the global illegal drug market. These substances are capable of producing rewarding effects similar to their parent drug. In anticipation of the future rise of new and similar psychoactive substances, we designed and synthesized four novel amphetamine derivatives with N-benzyl, N-benzylamphetamine HCl (NBNA) substituent on the amine region, 1,4-dioxane ring, ethylenedioxy-amphetamine HCl (EDA), methyl, para-methylamphetamine HCl (PMEA), and naphthalene, 2-(aminopropyl) naphthalene HCl (2-APN) substituents on the phenyl site. Then, we evaluated their abuse potential in the conditioned place preference (CPP) test in mice and self-administration (SA) test in rats. We also investigated the psychostimulant properties of the novel drugs using the locomotor sensitization test in mice. Moreover, we performed qRT-PCR analyses to explore the effects of the novel drugs on the expression of D1 and D2 dopamine receptor genes in the striatum. NBNA, but not EDA, PMEA, and 2-APN, induced CPP and SA in rodents. None of the test drugs have produced locomotor sensitization. qRT-PCR analyses demonstrated that NBNA increased the expression of striatal D1 dopamine receptor genes. These data indicate that NBNA yields rewarding effects, suggesting potential for abuse. Continual observation for the rise of related substances is thus strongly encouraged.

• Proceedings of the Korean Society of Toxicology Conference
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• 2006.11a
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• pp.46-54
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• 2006

The methylmercury (MeHg) is a toxic environmental pollutant, causing serious neurological and developmental effects in humans. Recent epidemiological studies have indicated that ingestion of MeHg in fish during pregnancy can result in neuroethological effects in the offspring. However, the mechanism underlying the MeHg-toxicity is not fully understood. To elucidate the mechanisms of toxicity of MeHg and of defense against MeHg, we searched for factors that determine the sensitivity of yeast cells to MeHg, and found that overexpression of Cdc34, a ubiquitin-conjugating enzyme (E2) that is a component of the ubiquitin-proteasome (UP) system, induces a resistance to MeHg toxicity in both yeast and human cells. The UP system is involved in the intracellular degradation of proteins. When Cdc34 is overexpressed in cells, ubiquitination reactions are activated and the degradation of certain proteins by the UP system is enhanced. Therefore, it seems likely that certain as-yet-unidentified proteins that increase MeHg toxicity might exist in cons and that toxicity might be reduced by the enhanced degradation of such proteins, mediated by the UP system, when Cdc34 is overexpressed. SCF ubiquitin-ligase is a component of UP system and consists of Skpl, the scaffold protein Cdc53, the RING-finger protein Hrt1, and one member of the family of F-box proteins. The F-box proteins directly bind to the substrates and are the determinants of substrate specificity of SCF. Therefore, we searched for the f-box protein that cofers resistance to MeHg, and found that overexpression of Hrt3 or Yi1224w induced resistance to MeHg toxicity in yeast cells. Since the protein(5) that enhance toxicity of MeHg might plausibly be induced in substrates of both f-box proteins, we next searched for substrate proteins that are recognized by Hrt3 or Y1r224w using two-hybrid screen. We found that Did3 or Crsl interacts with Hrt3; and Eno2 interacts with Yir224w. The yeast cells that overexpressed each those proteins showed hypersensitivity to MeHg, respectively, indicating that those proteins enhance the MeHg toxicity. Both Dld3 and Eno2 are proteins involved in the synthesis of pyruvate, and overexpression of both proteins might induce increase in interacellular levels of pyruvate. Deletion of Yi1006w that transports pyruvate into the mitochondria induced aresistance to MeHg. These results suggest that the promotion of the pyruvate irdlowinto the mitochondria might enhance MeHg toxicity. This study providesimportant keyfor the elucidauon of the molecular mechanism of MeHg toxicity.

• Analytical Science and Technology
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• v.18 no.4
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• pp.271-277
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• 2005

Urea in blood has been measured as an effective marker for diagnosis of renal function. Urea which is e end-product of nitrogen containing metabolites such as proteins is filtered through glomeruli of kidneys and then excreted as urine. If the renal function is deteriorated, the urea concentration in blood will be increased, from which the healthiness of renal function is judged. In order to improve the confidence of diagnosis results, the results must keep traceability chain to certified reference materials, which was certified by primary reference method. In this study, we proposed isotope dilution-liquid chromatography/mass spectrometry (ID-LC/MS) as a candidate primary method, in which $15^N_2$-urea is used as an internal reference material. The developed method is highly accurate in principle and is convenient as it does not require cumbersome derivatization. 0.1 mmol/L ammonium chloride was selected as a mobile phase for HPLC because it provided low interference in MS analysis of relatively low molecular weighted urea. HPLC and MS were connected with an electrospray ionization (ESI) interface of positive mode, which provided high sensitivity and reproducibility. The developed method was validated with internationally recognized reference materials, and we have obtained satisfactory results in an international ring trial. The expanded uncertainty calculated according to ISO guide was 1.8% at 95% confidence interval. The developed method is being used as a primary reference measurement method such as for certification of serum certified reference materials (CRMs).

• Journal of the Korean Chemical Society
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• v.60 no.1
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• pp.16-20
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• 2016

The solvolysis rate constants of biphenyl-4-carbonyl chloride (C₆H₅C₆H₅COCl, 1) in 19 different solvents are well correlated with the extended Grunwald-Winstein equation, using the N_T solvent nucleophilicity scale, Y_Cl solvent ionizing scale, and I aromatic ring parameter with sensitivity values of 0.31±0.10, 0.46±0.05, and 0.96±0.20 for l, m, and h, respectively. These l, m, and h values can be considered to support a dissciative S_N2 reaction pathway. This interpretation is further supported by the activation parameters, i.e., relatively small positive ΔH^‡ (15.3~16.1 kcal/mol) values and large negative ΔS^‡ (−17.2~−20.0 cal/mol·K) values.

• Polymer(Korea)
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• v.37 no.4
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• pp.420-430
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• 2013

Polymer blends were prepared by solution blending poly(amic acid) (PAA) and poly(o-hydroxy amide) (PHA) having imide groups in the main chain. The polymers and their blends were characterized by using FTIR, FT NMR, DSC, TGA, SEM, XRD, UTM, and LOI. The solubility study revealed that the blends were readily soluble in aprotic solvents such as DMF, DMAc, DMSO, and NMP. The maximum weight loss of the blends occurred in the range of $578-645^{\circ}C$, and the maximum weight loss temperature increased with increasing the PHA content. The PBO/PI blends showed relatively high char yields (i.e. 56-69 wt%). The LOI values of the blends were in the range of 24.5-28.1% and increased with increasing the PHA content. The initial modulus and tensile strength of the blends increased by 57 to 121% and by 67 to 107%, respectively, compared to the values of PAA. Especially the initial modulus and tensile strength of the PHA/PAA=2/8(wt/wt) showed the highest values of 4.87 GPa and 108 MPa, respectively. The PHA domains of $0.03-0.1{\mu}m$ in their size were more or less uniformly dispersed. The interfacial adhesion between PAA and PHA was found to be good.