• Title/Summary/Keyword: EAD

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Crystal Structure of LysB4, an Endolysin from Bacillus cereus-Targeting Bacteriophage B4

  • Hong, Seokho;Son, Bokyung;Ryu, Sangryeol;Ha, Nam-Chul
    • Molecules and Cells
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    • v.42 no.1
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    • pp.79-86
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    • 2019
  • Endolysins are bacteriophage-derived enzymes that hydrolyze the peptidoglycan of host bacteria. Endolysins are considered to be promising tools for the control of pathogenic bacteria. LysB4 is an endolysin produced by Bacillus cereus-infecting bacteriophage B4, and consists of an N-terminal enzymatic active domain (EAD) and a C-terminal cell wall binding domain (CBD). LysB4 was discovered for the first time as an L-alanoyl-D-glutamate endopeptidase with the ability to breakdown the peptidoglycan among B. cereus-infecting phages. To understand the activity of LysB4 at the molecular level, this study determined the X-ray crystal structure of the LysB4 EAD, using the full-length LysB4 endolysin. The LysB4 EAD has an active site that is typical of LAS-type enzymes, where $Zn^{2+}$ is tetrahedrally coordinated by three amino acid residues and one water molecule. Mutational studies identified essential residues that are involved in lytic activity. Based on the structural and biochemical information about LysB4, we suggest a ligand-docking model and a putative endopeptidase mechanism for the LysB4 EAD. These suggestions add insight into the molecular mechanism of the endolysin LysB4 in B. cereus-infecting phages.

A Study on the Design and Implementation of Metadata for Archival and Manuscripts Control (기록물정보 관리를 위한 메타데이터 설계와 구현에 관한 연구)

  • 김현희
    • Journal of the Korean Society for information Management
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    • v.18 no.4
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    • pp.57-79
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    • 2001
  • The study designs and implements a metadata management system for archival and manuscripts control. It has two purposes. First purpose is to organize the collection that the Institution of Korean Church History holds by using the proposed metadata format. Second purpose is to suggest the model and framework for managing the collection. The proposed metadata is designed based on ISAD(G), USMARC AMC, EAD and Ebind, By using the proposed metadata, the collection management system, which allows an integrated retrieval, is implemented. In order to evaluate the efficiency of the proposed system as well as to gain the basic data for the improvement of the proposed system, a questionnaire survey through e-mail is conducted. The evaluation results will be utilized for improving and upgrading the proposed system, and the phrased implementation of applying the system to digital libraries is suggested.

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A Study on Metadata Formats for Integration of Cultural Contents (문화콘텐츠 통합을 위한 메타데이터 포맷 연구)

  • Cho, Yoon-Hee
    • Journal of the Korean Society for information Management
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    • v.20 no.2
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    • pp.114-133
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    • 2003
  • Recently, the organizations related to cultural contents are gradually expanding access to cultural contents for general public through the distributed network. However, since cultural contents have different characteristics than general contents, the objects, the of cultural contents seldom contain the words generally used for organization and search of information. If the cultural contents system is created without any consideration of such differences. We cannot effectively identify and search resources. Moreover, because the names, expressions and meanings are different between metadata elements of various cultural contents, it is very difficult to interconnect or share information between different systems. In order to solve these problems, proper organization ad management of metadata is vital. In this studym we have comparatively analyzed the data elements of each format based on Dublin Core, EAD, VRA, CDWA, CIMI, and Object ID, the metadata formats approached from various aspects in the cultural contents area. Through this study, we tried to provide the basic materials for integration of cultural contents by securing interoperability of different metadata formats.

Sex Pheromone and Seasonal Occurrence of the peach leafminer, Lyonetia clerkella Linne (복숭아굴나방의 성페로몬과 성충 발생소장)

  • Yang Chang-Yeol;Jeon Heung-Yong;Kim Dae-Young;Kim Hyeong-Hwan
    • Korean journal of applied entomology
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    • v.45 no.1 s.142
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    • pp.25-30
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    • 2006
  • The female sex pheromone of the peach leafminer, Lyonetia clerkella Linne (Lepidoptera: Lyonetiidae), was analyzed by coupled gas chromatographic-electroantennographic detector (GC-EAD). GC-EAD analyses of pheromone gland extract revealed a single compound that elicited responses from male antennae. Retention time on DB-1 column of EAD-active compound was identical to that of synthetic (145)-14-Methyl-1-octadecene (14Sme-1-18Hy). In field tests, sticky traps baited with synthetic 14Sme-1-18Hy alone were highly attractive to male. Traps with 0.1 mg dose showed the lowest catches, but there were no significant difference in the numbers of moth caught in traps baited with doses of 0.5 and 1.0 mg. The results of the field assays for longevity of pheromone traps showed that effectiveness of lures maintained for at least 8 weeks under field condition. The attractiveness of 14Sme-1-18Hy was not affected by the addition of butylated hydroxytoluene (BHT) in lures as an antioxidant. Traps baited with 0.5 mg 14Sme-1-18Hy were successfully used to monitor L. clerkella male flights. Analysis of seasonal trap catches over two years showed that moth flight activity in peach orchards occurred over a period of seven months with six generations in Suwon.

Behavioral Response of the Lacewing Chrysopa cognata to both Aphis gossypii-induced Plant Volatiles and Chrysopa cognata-derived Volatiles (목화진딧물 감염 식물 및 칠성풀잠자리 유래-휘발성물질들에 대한 칠성풀잠자리의 행동 반응)

  • Cho, Jum Rae;Lee, Min Ho;Park, Chang Gyu;Kim, Jeong Hwan;Hooper, Tony;Woodcock, Christine;Pickett, John
    • Korean journal of applied entomology
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    • v.53 no.1
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    • pp.7-13
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    • 2014
  • This study was performed to investigate the response of the lacewing Chrysopa cognata to both Aphis gossypii-induced plant volatiles and lacewing-derived volatiles. The results of a Y-tube olfactometer bioassay showed that more C. cognata males were attracted to green pepper plants infected with A. gossypii than to uninfected green pepper plants alone or clean air and C. cognata males were attractive to C. cognata females. Gas chromatography-electroantennographic detection (GC-EAD) analysis showed that the antennae of C. cognata females elicited EAD-active responses to the volatiles entrained from A. gossypii-infected green pepper plants. 4-Ethylacetophenone, 3-ethylbenzaldehyde, 3-ethylacetophenone, and 4-ethylbenzaldehyde from A. gossypii-induced green pepper volatiles, and (Z,Z)-4,7-tridecadiene, (Z)-4-tridecene, and (Z)-4-undecene from C. cognata female entrainment were elucidated by further analysis using GC coupled nuclear magnetic resonance spectroscopy. Of the A. gossypii-induced plant volatiles identified in this study, 4-ethylacetophenone and 3-ethylbenzaldehyde significantly increased the attraction of C. cognata males to nepetalactol, but (Z)-4-tridecene and (Z)-4-undecene did not. (Z,Z)-4,7-Tridecadiene significantly reduced the attractiveness of nepetalactol to C. cognata.

Quantification of Entacapone in Human Plasma by HPLC Coupled to ESI-MS/MS Detection: Application to Bioequavalence Study (체외에서 ESI-MS/MS 탐지에 연결된 HPLC에 의한 Entacapon의 수량화: 생물학적 동등성 연구에 적용)

  • Balasekhara Reddy., Ch.;Baburao., Ch.;Chandrasekhar., K.B.;Kanchanamala., K.;RihanaParveen., S.K.;Ravikumar., Konda
    • Journal of the Korean Chemical Society
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    • v.54 no.5
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    • pp.523-532
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    • 2010
  • The proposed method is simple, sensitive and specific Liquid chromatography-tandem mass spectrometry (LCESI-MS/MS) method for the quantification of Entacapone (EA) in human plasma using Entacapone-d10 (EAD10) as an internal standard (IS). Chromatographic separation was performed on Zorbax SB-C18, $2.1{\times}50\;mm$, $5\;{\mu}m$ column, mobile phase composed of 10 mM Ammonium formate (pH 3.0): Acetonitrile (60:40 v/v), with a flow-rate of 0.7 mL/min, followed by Liquid-liquid extraction. EA and EAD10 were detected with proton adducts at m/z $306.1{\rightarrow}233.1$ and $316.3{\rightarrow}233.0$ in multiple reaction monitoring (MRM) positive mode respectively. The method was validated over a linear concentration range of 1.00 - 2000.00 ng/mL with correlation coefficient ($r^2$) $\geq$ 0.9993. Intra and inter-day Precision within 3.60 to 7.30 and 4.20 to 5.50% and Accuracy within 97.30 to 104.20 and 98.30 to 105.80% proved for EA. This method is successfully applied in the bioequivalence study of healthy Indian human volunteers.

Sensitivity Analysis of dVm/dtMax_repol to Ion Channel Conductance for Prediction of Torsades de Pointes Risk (다형 심실빈맥의 예측을 위한 dVm/dtMax_repol의 이온채널 전도도에 대한 민감도 분석)

  • Jeong, Da Un;Yoo, Yedam;Marcellinus, Aroli;Lim, Ki Moo
    • Journal of Biomedical Engineering Research
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    • v.43 no.5
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    • pp.331-340
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    • 2022
  • Early afterdepolarization (EAD), a significant cause of fatal ventricular arrhythmias including Torsade de Pointes (TdP) in long QT syndromes, is a depolarizing afterpotential at the plateau or repolarization phase in action potential (AP) profile early before completing one pace. AP duration prolongation is related to EAD but is not necessarily accounted for EAD. Several computational studies suggested EAD can form from an abnormality in the late plateau and/or repolarization phase of AP shape. In this sense, we hypothesized the slope during repolarization has the characteristics to predict TdP risk, mainly focusing on the maximum slope during repolarization (dVm/dtmax_repol). This study aimed to predict the sensitivity of dVm/dtmax_repol to ion channel conductances as a TdP risk metric through a population simulation considering multiple effects of simultaneous reduction in six ion channel conductances of gNaL, gKr, gKs, gto, gK1, and gCaL. Additionally, we verified the availability of dVm/dtmax_repol for TdP risk prediction through the correlation analysis with qNet, the representative TdP metric. We performed the population simulations based on the methodology of Gemmel et al. using the human ventricular myocyte model of Dutta et al. Among the sixion channel conductances, dVm/dtmax_repol and qNet responded most sensitively to the change in gKr, followed by gNaL. Furthermore, dVm/dtmax_repol showed a statistically significant high negative correlation with qNet. The dVm/dtmax_repol values were significantly different according to three TdP risk levels of high, intermediate, and low by qNet (p<0.001). In conclusion, we suggested dVm/dtmax_repol as a new biomarker metric for TdP risk assessment.

Measurement of the Elemental Composition in Airborne Particulate Matter Using Instrumental Neutron Activation Analys

  • Chung, Yong-Sam;Lim, Jong-Myoung;Moon, Jong-Hwa;Kim, Sun-Ha;Cho, Hyun-Je;Kim, Young-Jin
    • Nuclear Engineering and Technology
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    • v.36 no.5
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    • pp.450-459
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    • 2004
  • For the evaluation of emission sources by air sampling, airborne particulate matter for fine (<2.5 ${\mu}m2$ EAD : $PM_{2.5}$) and coarse partical (2.5-10 ${\mu}m2$ EAD : $PM_{2.5-10}$ fractions were collected using a Gent stacked filter unit low volume sampler and two types of polycarbonate filters. Air samples were collected twice monthly at two regions in and around Daejeon city in the Republic of Korea from January to December 2002. Monthly mass concentration of $PM_{2.5}$ and $PM_{2.5-10}$ were measured and the concentrations of 10 marker elements (Al, Sc, Ti ; Na, Cl ; As, V. Sb, Br, Se) were determined by an instrumental neutron activation analysis. Analytical quality control was corried out using certified reference materials. Enrichment factors were also calculated from the monitoring data to classify the anthropogenic and crustal origins.

A Study on the Design and Implementation of Metadata for Archival and Manuscripts Control (기록물정보관리를 위한 메타데이터 설계와 구현)

  • 김현희;정연대;안수현
    • Proceedings of the Korean Society for Information Management Conference
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    • 2001.08a
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    • pp.111-116
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    • 2001
  • 본 연구에서는 기록물 자료를 관리 수 있는 메타데이터 형식을 설계하기 위해서 기록물의 목록 규칙과 관련된 네 가지 종류의 자료 즉 국제표준기록물기술$\ulcorner$ISAD(G)], 미국 기록물/필사본 기계가독목록(USMARC AMC), MARC21 및 EAD(Encoded Archival Description)를 참조한 다음 전통적인 도서관 자료와의 통합검색을 가능하게 하면서 기록물정보의 고유의 속성을 잘 표현할 메타데이터(목록 레코드와 인벤토리)를 설계하여 구현해 보았다.

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Cycloadditiona reaction of 5-(2-thienyl)methylene derivatives of thiazolidinone-4-thiones and their antimicrobial activities

  • Ead, Hamed A.;Metwalli, Nadia H.;Morsi, Nagwa M.
    • Archives of Pharmacal Research
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    • v.13 no.1
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    • pp.5-8
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    • 1990
  • The cycloaddition of the newely synthesized 5-(2-thienyl)methylene derivatives of thiazolidinone-4-thiones, 2a-c to acrylonitrile (3a), ethylacrylate (3b), N-phenylmaleimide (6) and dimethyl fumarate (8) has been evaluated. Under thermal reaction conditions [4 +2] cycloaddition proceeds with complete site and regioselectivity to yield the cycloadduct, 4, 5, 7 and 9, respectively. The antimicrobial activities of some of the new products were tested.

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