• Genomics & Informatics
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• 제15권4호
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• pp.147-155
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• 2017

Apurinic/apyrimidinic endonuclease 1 (APE1) is an enzyme responsible for the initial step in the base excision repair pathway and is known to be a potential drug target for treating cancers, because its expression is associated with resistance to DNA-damaging anticancer agents. Although several inhibitors already have been identified, the identification of novel kinds of potential inhibitors of APE1 could provide a seed for the development of improved anticancer drugs. For this purpose, we first classified known inhibitors of APE1. According to the classification, we constructed two distinct pharmacophore models. We screened more than 3 million lead-like compounds using the pharmacophores. Hits that fulfilled the features of the pharmacophore models were identified. In addition to the pharmacophore screen, we carried out molecular docking to prioritize hits. Based on these processes, we ultimately identified 1,338 potential inhibitors of APE1 with predicted binding affinities to the enzyme.

• 생명과학회지
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• 제19권1호
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• pp.138-146
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• 2009

마늘은 역학조사에 의하면 각종 질환의 예방과 치료에 효능이 있는 것으로 알려져 있다. 마늘의 주요 성분인 알리신 성분은 매우 불안정하여 쉽게 분해되어 새로운 형태의 유황 화합물로 만들어져 이들 성분들이 상승적으로 작용하여 중요한 생리황성을 갖는 것으로 알려져 있다. 시판되고 있는 여러 종류의 마늘제품 중에서 숙성마늘제품이 다른 제품에 비하여 생리활성이 높은 것으로 보고되었다. 숙성마늘제품은 마늘을 일정한 조건으로 숙성시킬 때 수용성 성분인 S-allylcysteine, S-allylmercaptan, steroid saponins, te-trahydro-${\beta}$-caboline derivatives 및 fructeosyl-arginine 등이 많이 증가하여 그 효능이 상승적으로 높아지는 것으로 알려져 있다. 따라서 시판 마늘가공품의 품질을 표준화하기 위하여 이들 수용성 성분을 biomarker로서 규격기준을 정해야 할 것이다.

• 한국미생물·생명공학회지
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• 제26권5호
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• pp.379-386
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• 1998

본 연구에서는 천연 항균물질의 개발 이용을 위해 황기 종자로부터 인체에 무해한 천연 항균 단백질을 ion exchange chromatography 및 gel filteration을 이용하여, 순수 분리하고 특성을 조사하였다. 황기종자로부터 추출한 천연 항균 단백질은 Aspergillus ocraceus, Penicillium expensum, P. digitatum, Botrytis cineria의 포자 발아 및 효모인 Candida albicans의 생육을 현저하게 저해하였으며 ammonium sulfate 포화도가 0.4일 때 단백질의 침전량이 122.6 $\mu\textrm{g}$/$m\ell$로 가장 많았고 항균력도 15.2 mm로 가장 높게 나타났다. 강력한 cation exchange chromatography인 Mono-S를 이용하여 FPLC에서 단백질을 분획하였을때 첫번째 peak에서 분획된 단백질군이 항균력을 보였으며 Superose 12HR gel filteration column을 이용하여 2차 분획 하였을 때 분자량이 19 kDa되는 단일 단백질만을 순수분리 할 수 있었다. 전기 영동한 polyacrylamide gel위에 곰팡이 포자를 중층하는 bio autography로 19 kDa 단백질 band의 항균력을 직접 확인하였으며 분리된 항균 단백질의 아미노 말단의 아미 노산 22잔기를 sequencing하고 thaumatin 및 zeamatin 유사 단백질들과 상동성을 측정한 결과 50%내외의 homology를 나타내었다. 분리된 항균 단백질은 곰팡이 균사가 성장하는 선단부위에 가장 먼저 침투하여 channel을 형성함으로 osmolysis를 일으켜 곰팡이의 생육을 억제하는 것으로 추측할 수 있었다.

• Archives of Pharmacal Research
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• 제27권3호
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• pp.273-277
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• 2004

In previous studies for the development of new anticonvulsants, we found that N-Cbz-$\alpha$-amino-N-alkylsuccinimides exhibited significant anticonvulsant activities in the Maximal electroshock seizure (MES) and Pentylenetetrazole induced seizure (PTZ) tests, and also their anticonvulsant activities were dependent on the N-alkyl substituents existent in their structures. Based on these estimations, N-Cbz-$\alpha$-amino-N-hydroxysuccinimide and various N-Cbz-$\alpha$-amino-N-alkoxysuccinimides were prepared in order to develop more active anticonvulsants and to examine the effects of N-hydoxy or N-alkoxy groups on their anticonvulsant activities. The (R)-or (S)-N-Cbz-$\alpha$-amino-N-hydroxysuccinimide and N-Cbz-$\alpha$-amino-N-alkoxysuccinimides were prepared from the corresponding (R)-or (S)-N-Cbz-aspartic acid through the known synthetic procedures. Their anticonvulsant activities in the MES and PTZ test were evaluated. All of these compounds except 3a showed significant anticonvulsant activities against the PTZ test, but these compounds were not active in the MES test. The most active compound in the PTZ test was (R)-N-Cbz-$\alpha$-amino-N-benzyloxysuccinimide (ED$_{50}$=62.5 mg/kg). In addition, the anti-convulsant activities of these compounds were dependent on their N-substited groups. The order of anticonvulsant activity against the PTZ test, as judged from the ED50 values for (R) series was N-benzyloxy > N-hydroxy > N-isopropoxy > N-methoxy > N-ethoxy; for the (S) series N-ethoxy > N-benzyloxy > N-methoxy > N-isopropoxy.y.

• Journal of Magnetics
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• 제4권2호
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• pp.65-68
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• 1999

The M-type barium ferrite ($BaFe_{12}O_{19}$) is well known magnetic material to be used as a permanent magnet due to its strong uniaxial anisotropy. The substitution of nonmagnetic $Ti^{+4}$ and magnetically weak $Co+^2ion for Fe^{+3}$ to its strong uniaxial anisotropy. The substitution of nonmagnetic $Ti^{+4}$ and magnetically weak $Co+^2ion for Fe^{+3}$ sublattices reduces the uniaxial anisotropy and those compounds open a new application field of noise suppressor at high frequencies. In this study, the magnetic and microwave absorbing properties are investigated in Ti-and Co-substituted barium ferrites ($BaFe_{12-2X} Ti_XCo_XO_{19}$). The saturated magnetization decreases linearly with the substitution of Ti and Co. The rapid drop in coercive force is observed with Ti and Co substitution upto x=1.2. The magnetic permeability spectrum shows the natural magnetic resonance in the specimens with small coercive force and large attenuation of microwave is predicted in those specimens at high frequencies (above 4 GHz).

• 한국분말재료학회지
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• 제8권1호
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• pp.61-69
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• 2001

Spark-Plasma Sintering(SPS) is one of the new sintering methods which takes advantages both inconventional pressure sintering and electric current sintering. It is known that SPS is very effective for the densification of hard-to-sinter materials like refractory metals, intermetallic compounds, glass and ceramics without grain growth. However, a clear explanation for sintering mechanism and an experimental evidence for the formation of weak plasma during SPS are not given yet. In this study, fundamental study on sintering behavior and mechanism of SPS was investiged. For this study, various spherical Fe powders were prepared such as as-received, as-reduced, and as-oxidized and then sintered by SPS facility. In order to confirm the surface cleaning effect during SPS neck region and fracture surface of sintered body was observed and analyzed by SEM/EPMA. Densification behavior was analyzed from the data of deflection along the pressure axis. Some specimens were additionally produced by Hot Pressing and the results were compared with those of SPS.

• Natural Product Sciences
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• 제16권1호
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• pp.15-19
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• 2010

A new 2,7'-cyclolignan named lonicerinol (1) along with eight known lignans, (-)-epipinoresinol (2), (-)-pinoresinol (3), $9{\alpha}$-hydroxypinoresinol (4), 7R,8S-dihydrodehydrodiconiferyl alcohol (5), ($\pm$)-neo-olivil (6), (+)-isolariciresinol (7), 3-methoxy-8,4'-oxyneoligna-3',4,7,9,9'-pentol (8), and (-)-pinoresinol 4-O-glucoside (9), were isolated from the caulis of Lonicera japonica THUNB. (Caprifoliaceae). All of these constituents except for (-)-pinoresinol (3) and $9{\alpha}$-hydroxypinoresinol (4) are reported for the first time from the genus Lonicera. The structures and absolute configurations of these compounds were determined on the basis of spectroscopic analysis, including CD and 1D- and 2D-NMR techniques and chemical methods.

• BMB Reports
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• 제43권11호
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• pp.711-719
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• 2010

Kinomics is an emerging and promising approach for deciphering kinomes. Chemical kinomics is a discipline of chemical genomics that is also referred to as "chemogenomics", which is derived from chemistry and biology. Chemical kinomics has become a powerful approach to decipher complicated phosphorylation-based cellular signaling networks with the aid of small molecules that modulate kinase functions. Moreover, chemical kinomics has played a pivotal role in the field of kinase drug discovery as it enables identification of new molecular targets of small molecule kinase modulators and/or exploitation of novel functions of known kinases and has also provided novel chemical entities as hit/lead compounds. In this short review, contemporary chemical kinomics technologies such as activity-based protein profiling, T7 kinasetagged phages, kinobeads, three-hybrid systems, fluorescenttagged kinase binding assays, and chemical genomic profiling are discussed along with a novel allosteric Bcr-Abl kinase inhibitor (GNF-2/GNF-5) as a successful application of chemical kinomics approaches.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 1998년도 학술발표회논문집
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• pp.242-244
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• 1998

Over the years manufactures have become increasingly aware of the importance of water purity and its effect on the quality of the final product. One of the largest problems that confronts pure water system operators is bacterial recontamination shortly after the water purification equipment. There are several recommended methods of either preventing or recommended methods of either preventing or removing such contamination but most have inherent disadvantages. Drinking water has required new treatment techniques such as ozonation and granular activated carbon(GAC) filtration. Ozone is known to be a powerful oxidant and disinfectant. Therefore it has been found to be necessary for the treatment of taste, odor and color as an oxidant of inorganic and organic compounds.

• Bulletin of the Korean Chemical Society
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• 제34권10호
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• pp.3013-3016
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• 2013

Two new isoflavanones, (3R) 7,2',4'-trihydroxy-3'-methoxy-5-methoxycarbonyl-isoflavanone (1) and (3R) 7,2'-dihydroxy-3',4'-dimethoxy-5-methoxycarbonyl-isoflavanone (2), together with six known isoflavanones (3-8), were isolated from the stems of Cassia siamea. The structure of 1-8 was elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Compounds 1, 2, 5-8 were evaluated for their anti-tobacco mosaic virus (Anti-TMV) activity. The results showed that compounds 1 and 6 showed potential anti-TMV activity with inhibition rates of 24.6% and 26.9%, respectively. Compounds 2, 5, 7, 8 also showed anti-TMV activity with inhibition rates in the range of 11.8-18.6%.