• Bulletin of the Korean Chemical Society
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• 제28권8호
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• pp.1335-1340
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• 2007

β-Ketoacyl acyl carrier protein synthase (KAS) III is a particularly attractive target in the type II fatty acid synthetic pathway, since it is central to the initiation of fatty acid synthesis. Enterococcus faecalis, a Grampositive bacterium, is one of the major causes of hospital acquired infections. The rise of multidrug-resistant of most bacteria requires the development of new antibiotics, such as inhibition of the KAS III. In order to block the fatty acid synthesis by inhibition of KAS III, at first, three dimensional structure of Enterococcus faecalis KAS III (efKAS III) was determined by comparative homology modeling using MODELLER based on x-ray structure of Staphylococcus aureus KAS III (saKAS III) which is a gram-positive bacteria and is 36.1% identical in amino acid sequences with efKAS III. Since His-Asn-Cys catalytic triad is conserved in efKAS III and saKAS III, substrate specificity of efKAS III and saKAS III and the size of primer binding pocket of these two proteins are expected to be similar. Ligand docking study of efKAS III with naringenin and apigenin showed that naringenin docked more strongly with efKAS III than apigenin, resulting in the intensive hydrogen bond network between naringenin and efKAS III. Also, only naringenin showed antibacterial activity against E. faecalis at 256 μg/mL. This study may give practical implications of flavonoids for antimicrobial effects against E. faecalis.

• Bulletin of the Korean Chemical Society
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• 제32권9호
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• pp.3219-3222
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• 2011

Three types of ${\beta}$-ketoacyl acyl carrier protein synthase (KAS) are important for overcoming the bacterial resistance problem. Recently, we reported the discovery of a antimicrobial flavonoid, YKAF01 (3,6-dihydroxyflavone), which exhibits antibacterial activity against Gram-positive bacteria through inhibition of ${\beta}$-ketoacyl acyl carrier protein synthase III (KAS III). In this report, we suggested that YKAF01 can be an inhibitor ${\beta}$-ketoacyl acyl carrier protein synthase I (KAS I) with dual inhibitory activity for KAS I as well as KAS III. KAS I is related to the elongation of unsaturated fatty acids in bacterial fatty acid synthesis and can be a good therapeutic target of designing novel antibiotics. We performed docking study of Escherichia coli KAS I (ecKAS I) and YKAF01, and determined their binding model. YKAF01 binds to KAS I with high binding affinity ($2.12{\times}10^6$) and exhibited an antimicrobial activity against the multidrug-resistant E. coli with minimal inhibitory concentration (MIC) value of 512 ${\mu}g$/mL. Further optimization of this compound will be carried out to improve its antimicrobial activity and membrane permeability against bacterial cell membrane.

• Bulletin of the Korean Chemical Society
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• 제32권8호
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• pp.2695-2699
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• 2011

${\beta}$ Ketoacyl acyl carrier protein synthase III (KAS III) initiates fatty acid synthesis in bacteria and is a key target enzyme to overcome the antibiotic resistance problem. In our previous study, we found flavonoid inhibitors of Enterococcus faecalis KAS III and proposed three potent antimicrobial flavonoids against Enterococcus faecalis and Vancomycin-resistant Enterococcus faecalis with MIC values in the range of 128-512 ${\mu}g/mL$ as well as high binding affinities on the order from $10^6$ to $10^7\;M^{-1}$. Using these series of flavonoids, we conducted biological assays as well as docking study to find potent flavonoids inhibitors of Staphylococcus aureus KAS III with specificities against Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus. Here, we propose that naringenin (5,7,4'-trihydroxyflavanone) and eriodictyol (5,7,3',4'-tetrahydroxyflavanone) are potent antimicrobial inhibitors of Staphylococcus aureus KAS III with binding affinity of $3.35{\times}10^5$ and $2.01{\times}10^5\;M^{-1}$, respectively. Since Arg38 in efKAS III is replaced with Met36 in saKAS III, this key difference caused one hydrogen bond missing in saKAS III compared with efKAS III, resulting in slight discrepancy in their binding interactions as well as decrease in binding affinities. 4'-OH and 7-OH of these flavonoids participated in hydrogen bonding interactions with backbone carbonyl of Phe298 and Ser152, respectively. In particular, these flavonoids display potent antimicrobial activities against various MRSA strains in the range of 64 to 128 ${\mu}M$ with good binding affinities.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1645-1649
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• 2011

[ ${\beta}$ ]Ketoacyl acyl carrier protein synthase I (KAS I) is involved in the elongation of unsaturated fatty acids in bacterial fatty acid synthesis and a therapeutic target of designing novel antibiotics. In this study, we performed receptor-oriented pharmacophore-based in silico screening of E. coli KAS I (ecKAS I) with the aim of identifying novel inhibitors. We determined one pharmacophore map and selected 8 compounds as candidates ecKAS I inhibitors. We discovered one antimicrobial compound, YKAe1008, N-(3-pyridinyl) hexanamide, displaying minimal inhibitory concentration (MIC) values in the range of 128-256 ${\mu}g/mL$ against MRSA and VREF. YKAe1008 was subsequently assessed for binding to ecKAS I using saturation-transfer difference NMR spectroscopy. Further optimization of this compound will be carried out to improve its antimicrobial activity and membrane permeability against bacterial cell membrane.

• 복식
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• 제40권
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• pp.25-35
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• 1998

This thesis is a study of Kas ya, robes of buddhist monk, which is having peculiarity among human clothes. I kept my attention mainly on the symbolism of the color of Kas ya. To elucidate this, I chose the principle of T -chi and Yin-yang and Wu-shing as a frame-work of interpretation. In the first place, the original meaning of Kas ya mean a name of peculiar color. The concrete names of the color are color of persimmons juice, brown, yellow tinged with red, radish brown, non-primary color etc. The main motive to dye three robes of buddhist monk from white or primary color to the color of Kas ya was to differentiate buddhist monks from heathen or laymen. Therefore, as luxurious and primary colored cloths was donated to the buddhist monks, they are necessary to discolor them. Accordingly. they established 'non-primary color' as well-mate one for a ascetic. The non-primary color is called discolored color' as a result of discoloring primary colors. The discolored color is a synonym of Kas ya and the process of discoloring is necessary for making robes of buddhist monk. Secondly, discoloring means to mash five primary color. That is say, the process of discoloring means to return five primary colors back to 'profoundity·abstruseness·obscurity, namely darkness' as the source of them. Darkness as a condition amalgamated and not appeared all materials is the source and at the same time the terminus of all colors. Therefore, color of Kas ya symbolizes 'profound color' as the ultimate meaning of discoloring. Thirdly, discoloring garments of buddhist monk symbolize to destroy evil passions and haughtiness arising in ascetic's mind as well as means don't attach to the shaped materials'. Fourthly, discoloring means to return 'color'. namely 'all kinds of shaped material' to the inherent nature. Process of discoloring means to reture to the empty. nya. nya essentially do not make any colors, but over and over again come into being and become extinct as becoming colors. R pa, by one time Yin and the other time Yang'. R pa, color is a metaplasia of nya and nya is discoloring one of all colors. Then, discoloring means R pa is nya, R pa is nya at the same time and Because this is another expression of Dharma the original meaning of Kas ya symbolize true robes. Consequently, Kas ya means truth and beyond time and space do not be changed and conserve the color of the first till now.

• Asia Marketing Journal
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• 제22권4호
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• pp.171-173
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• 2021

This editorial briefly explains the overview of the special session papers of ICAMA (International Conference of Asian Marketing Associations)-KAS (Korea Advertising Society). We also present the general direction for progressing the development of AMJ. Most of all, this special session was made possible because of the contribution of Professor Kyunghee Bu, the Rhizomatic Revolution Review and the BTS ARMY.

• 한국토양비료학회지
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• 제17권4호
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• pp.363-370
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• 1984

토양(土壤)의 가리공급력(加里供給力)에 따른 시비량(施肥量) 추정(推定)에 활용(活用)하기 위(爲)하여 수도(水稻)의 출수기(出穗期) 및 시험전(試驗前) 토양(土壤)에서 Gapon식(式)의 계수(係數) $KG_o$와 상대가리활성도비(相對加里活性度比) Kas/kai를 구(求)하고 이들 요인(要因)과 수도(水稻)의 가리흡수량(加里吸收量) 및 정조수량(正租水量)과의 관계(關係)를 비교(比較) 검토(檢討)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 시험전(試驗前) 토양(土壤)에서 조사(調査)된 ${\Delta}K=0$일때의 Gapon계수(係數) $KG_o$는 식양토(埴壤土) 7.8 양토(壤土) 6.6 사양토(砂壤土) 7.1 이었고 상대가리활성도비(相對加里活性度比) Kas/kai는 식양토(埴壤土) 1.37 양토(壤土) 1.26 사양토(砂壤土) 2.11로 토성(土性)에 따라 상이(相異)하였다. 2. 출수기(出穗期) 토양(土壤)에서 조사(調査)된 KG는 수도(水稻)의 생육(生育)과 함께 그 값이 커져서 가리무시용(加里無施用) 수준(水準)의 값과 동일수준(同一水準)으로 될때 가리(加里)의 시용효과(施用效果)가 현저(顯著)하였다 3. 토양중(土壤中) 치환성(置換性) 양(陽)이온비(比)[Kex./(Ca+Mg) ex.]와 평형용액중(平衡溶液中) 가리활성도비(加里活性度比) ($[K^+]/\sqrt{[Ca^{{+}{+}}+Mg^{{+}{+}}]}$) 사이에는 토성(土性)에 따라 기울기가 다른 직선적(直線的)인 상관관계(相關關係)를 보였다. 4. 출수기(出穗期) 토양중(土壤中) $KG_o$와 Kas/kai는 질소(窒素) 15kg/10a 시용시(施用時) 식물체(植物體)의 가리흡수량(加里吸收量) 및 정조수량(正租收量)과 높은 상관관계(相關關係)를 보었으며 시험전(試驗前) 토양(土壤)에서 산출(算出)된 Kas/Kai는 가리흡수량(加里吸收量) 및 정조수량(正租收量)과 높은 상관(相關)을 보여 좋은 가리공급력(加里供給力) 지표(指標)로 판단(判斷)되었다. 5. 출수기(出穗期) 토양(土壤)의 KG와 Kas/kai는 높은 부(負)의 상관관계(相關關係)를 보여 서로 반대(反對)된 요인(要因)으로 생각되며 가리시비량(加里施肥量) 추정(推定)에 활용(活用)이 가능(可能)할 것으로 보인다.

• 한국식품영양과학회지
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• 제40권9호
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• pp.1279-1284
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• 2011

본 연구에서는 도토리묵 제조용으로 수입되고 있는 북한산, 중국산 전분과 국내산 전분에 대하여 원산지별 호화 특성을 알아보기 위해 청가, 아밀로오스 함량, 아밀로그래프 측정, 입도분포, 장방출주사전자현미경에 의한 입자형태 등을 조사하였다. 청가는 북한산($0.42{\pm}0.00$)> 중국산($0.37{\pm}0.01$)> 국내산($0.34{\pm}0.00$) 순이었고(p<0.05), 아밀로오스 함량에서는 북한산($33.65{\pm}0.47$)> 중국산($32.00{\pm}0.86$)> 국내산 ($30.48{\pm}1.21$) 순이었다(p<0.05). 아밀로그래프상에 나타난 초기호화온도는 북한산과 중국산이 $72^{\circ}C$로 같았고, 국내산은 $71^{\circ}C$이었다. 최고점도는 국내산과 북한산이 580 BU이었고 중국산은 570 BU이었다. 전분의 노화특성과 밀접한 상관관계를 나타내는 냉각점도(C)와 setback(C-P)값, total setback(C-H)값의 크기는 전분의 노화정도를 나타내는 값으로 북한산과 중국산이 국내산보다 다소 높았다. 입자분포에서는 5 미크론 이상 40 미크론 미만에서 국내산 68.9%, 중국산 73.8%를 나타낸 반면 북한산은 57.1%, 90 미크론 이상 501 미크론 미만에서의 입자가 19.1% 함유되어 있어 상당히 불균일하였다. 장방출주사전자현미경 관찰 결과 중국산과 북한산 시료에서 부분적으로 호화가 일어났다.

• 항공우주기술
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• 제11권2호
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• pp.216-224
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• 2012

본 연구는 국내에서 개발되는 KAS 23급 민간항공기에 대해 형식증명을 취득하기 위한 절차와 방법에 대해 기술하였다. 인증기준을 수립하고 형식증명 계획서에 따라 시험평가를 통해 적합성을 입증하는 절차와 적합성 입증 방안을 제시함으로써 정해진 기간 내 형식증명을 취득하는 것이 가장 중요하다고 하겠다. 본 절차는 미 FAA Order 8110.4C, 'Type Certification'과 국내규정을 참고하였으며 적합성 입증방법(MOC)을 정의하여 적합성 점검표(CCL) 작성 사례를 보여주고 있다. 또한 적합성 입증방법에 따라 시험평가 항목을 분류 하였고 그 방안을 제시하였다.

• 대한한의학회지
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• 제42권2호
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• pp.82-89
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• 2021

Objectives: The purpose of this study was to examine the curriculum of the medical humanities and social medicine at 11 Colleges of Korean Medicine (CKM) based on the Korean Medicine Education Accreditation Standards 2021 (KAS2021) and suggest ways to improve the quality of Korean Medical education in the future. Methods: The curricula for each grade were collected from the websites of 11 CKM. Based on KAS2021, medical humanities and social medicine courses were extracted and compiled. Courses offered, frequency of course offerings, time of offerings, credits, and course hours were investigated. Results: Courses in languages and literature were most frequently offered in CKM. Most medical humanities and social medicine courses were offered in the pre-medical program and the fourth year of the medical program and were conducted as individual courses. Developing a curriculum that integrates conceptual definitions of the medical humanities and social medicine with basic and clinical studies is necessary. Conclusion: Eleven CKM should reorganize and operate their medical humanities and social medicine curricula based on each college's circumstances. This will allow each college to improve the quality of its educational offerings, creating a foundation for fostering excellent korean medicine doctors with professional medical skills and communication skills.