• Title/Summary/Keyword: position-domain

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Directed Mutagenesis of the Bacillus thuringiensis Cry11A Toxin Reveals a Crucial Role in Larvicidal Activity of Arginine-136 in Helix 4

  • Angsuthanasombat, Chanan;Keeratichamreon, Siriporn;Leetacheewa, Somphob;Katzenmeier, Gerd;Panyim, Sakol
    • BMB Reports
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    • v.34 no.5
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    • pp.402-407
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    • 2001
  • Based on the currently proposed toxicity model for the different Bacillus thuringiensis Cry $\delta$-endotoxins, their pore-forming activity involves the insertion of the ${\alpha}4-{\alpha}5$ helical hairpin into the membrane of the target midgut epithelial cell. In this study, a number of polar or charged residues in helix 4 within domain I of the 65-kDa dipteranactive Cry11A toxin, Lys-123, Tyr-125, Asn-128, Ser-130, Gln-135, Arg-136, Gln-139 and Glu-141, were initially substituted with alanine by using PCR-based directed mutagenesis. All mutant toxins were expressed as cytoplasmic inclusions in Escherichia coli upon induction with IPTG. Similar to the wild-type protoxin inclusion, the solubility of each mutant inclusion in the carbonate buffer, pH 9.0, was relatively low When E. coli cells, expressing each of the mutant proteins, were tested for toxicity against Aedes aegypti mosquito-larvae, toxicity was completely abolished for the alanine substitution of arginine at position 136. However, mutations at the other positions still retained a high level of larvicidal activity Interestingly, further analysis of this critical arginine residue by specific mutagenesis showed that conversions of arginine-136 to aspartate, glutamine, or even to the most conserved residue lysine, also abolished the wild-type activity The results of this study revealed an important determinant in toxin function for the positively charged side chain of arginine-136 in helix 4 of the Cry11A toxin.

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Design and Evaluation of a GNSS Receiver Network For Lane-By-Lane Traffic Monitoring (차선별 교통 모니터링을 위한 위성항법 수신기망 설계 및 성능 평가)

  • Kim, Hee-Sung;Lee, Hyung-Keun
    • Journal of Advanced Navigation Technology
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    • v.14 no.2
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    • pp.151-160
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    • 2010
  • For the realization of future intelligent transportation systems, fine-grained lane-by-lane traffic monitoring and control functionalities are among the most important technology barriers to overcome. To satisfy the accuracy requirement for traffic monitoring, a GNSS receiver network is designed. The designed receiver network consists of three different types of entities; reference server, broadcaster, and client. For deployment flexibility, all the entities utilize the international message standard RTCM SC-104 version 3.0. For fine-grained traffic monitoring, the client is designed to utilize position-domain carrier-smoothed-code filters to provide accurate vehicle coordinates in spite of frequent addages and outages of visible satellites. An experiment result is presented to evaluate the positioning accuracy of the proposed method.

ER Stress-Induced Jpk Expression and the Concomitant Cell Death

  • Kim Hye Sun;Chung Hyunjoo;Kong Kyoung-Ah;Park Sungdo;Kim Myoung Hee
    • Biomedical Science Letters
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    • v.11 no.2
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    • pp.135-141
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    • 2005
  • A Jopock (Jpk), a trans-acting factor associating with the position-specific regulatory element of murine Hoxa-7, has shown to have a toxicity to both prokaryotic and eukaryotic cells when overexpressed. Since Jpk protein harbors a transmembrane domain and a putative endoplasmic reticulum (ER)-retention signal at the N-terminus, a subcellular localization of the protein was analyzed after fusing it into the green fluorescent protein (GFP): Both N-term (Jpk-EGFP) and C-term tagged-Jpk (EGFP-Jpk) showed to be localized in the ER when analyzed under the fluorescence microscopy after staining the cells with ER- and MitoTracker. Since ER stress triggers the ER-stress mediated apoptosis to eliminate the damaged cells, we analyzed the expression pattern of Jpk under ER-stress condition. When MCF7 cells were treated with the ER-stress inducer such as DTT and EGTA, the expression of Jpk was upregulated at the transcriptional level like that of Grp78, a molecular chaperone well known to be overexpressed under ER-stress condition. In the presence of high concentration of ER-sterss inducer (10 mM), about 70 (DTT) to $95\%$ (EGTA) of cells died stronly expressing ($10\~12$ fold) Jpk. Whereas at the low concentration ($0.001\~1.0\;mM$) of the inducer, the expression of Jpk was increased about 2.5 (EGTA) to 5 fold (DTT), which is rather similar to those of ER chaperone protein Grp78. These results altogether indicate that the ER-stress upregulated the expression of Jpk and the excess stress induces the ER-stress induced apoptosis and the concomitant expression of Jpk.

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Identification of the Hybrid Cluster Protein, HCP, from Amitochondriate Eukaryotes and Its Phylogenetic Implications

  • Han, Kyu-Lee;Yong, Tai-Soon;Ryu, Jae-Sook;Hwang, Ui-Wook;Park, Soon-Jung
    • Journal of Microbiology and Biotechnology
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    • v.14 no.1
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    • pp.134-139
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    • 2004
  • Hybrid cluster protein (HCP) was investigated because of its unique iron-sulfur clusters, which have been found in bacteria and archaea. Here, HCP homologous proteins from the third domain, 'eukarya'(3 amitochondriate protozoans, Giardia lamblia, Entamoeba histolytica, and Trichomonas vaginalis), were identified. All three amitochondriate protozoan HCPs (GlHCP, EhHCP, and TvHCP) belonged to Class I on the basis of two key characters, the cysteine spacing, Cys-(Xaa)₂Cys(Xaa)/sub 7-8/-Cys(Xaa)/sub 5/-Cys, and the absence of N-terminal deletion characteristic to the Class III. In phylogenetic analysis performed with amino acid sequences of 3 eukaryal, 5 bacterial, and 4 archaeal HCPs, the maximum likelihood (ML) tree indicated that TvHCP was clustered with Class I HCPs, whereas the other two HCPs (GlHCP and EhHCP) formed an independent clade with a high bootstrapping value (96%) not belonging to any previously recognized HCP class. In spite of the relatively lower bootstrapping value (61%), the position of the new eukaryal GlHCP-EhHCP clade was close to Class I, including the TvHCP, and Classes II and III were closely related with each other. The finding of eukaryal HCPs would help to understand the evolutionary history of HCP.

Transient Effects of Wind-wave Hybrid Platform in Mooring Line Broken Condition (부유식 파력-해상풍력 복합발전 구조물의 계류선 손상 시 과도 응답 해석)

  • Bae, Yoon Hyeok;Lee, Hyebin
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.19 no.2
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    • pp.129-136
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    • 2016
  • Floating offshore structures keep its position by a mooring system against various kind of environmental loadings. For this reason, a reliable design of the mooring system is a key factor for initial design stage of a floating structure. However, there exists possibility of mooring failure, even the system is designed with enough safety margin, due to the unexpected extreme environmental conditions or long-term fatigue loadings. The breaking of one of the mooring lines may change the tension level of the other mooring lines, which can potentially result in a progressive failure of the entire structure. In this study, time domain numerical simulation of 10MW class wind-wave hybrid platform was carried out with partially broken mooring line. Overall platform responses and variations of the mooring line tension were numerically evaluated.

Heart Sound Recognition by Analysis of Block Integration and Statistical Variables (구간적분과 통계변수 분석에 의한 심음 인식)

  • 이상민;김인영;홍승홍
    • Journal of Biomedical Engineering Research
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    • v.20 no.6
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    • pp.573-581
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    • 1999
  • Although phonocardiography by auscultation has been used in diagnosis long time ago, recognition of heart sound was tried only restricted fields such as the first heart sound, the second heart sound, and specific valve operation for the purpose of analyzing local function or operation of heart and developments of heart sound recognition in full cycle are quite insignificant. in this paper, we proposed a recognition method which extracts features of heart sound in full cycle and classllies heart sounds This proposed recognition algorithm is based on detecting the first and second heart sounds in thme domain. The algorithm classifics heart sound into several classes by extracting the important time blocks and analyzing the peak position, integration values and statistical variables. Heart sounds are classified into normal, early systolic murmur, late systolic mumur, early diastolic murmur, late diastolie murmur, continuous murmur. We can verify our algorithm is useful from the results which show the average recognition rate of heart sounds is 88 perecnt. Recognition error was occurred mainly in early systolic murmur.

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Physicians' perception of and attitudes towards patient safety culture and medical error reporting (환자안전 문화와 의료과오 보고에 대한 의사의 인식과 태도)

  • Kang, Min-Ah;Kim, Jeong-Eun;An, Kyung-Eh;Kim, Yoon;Kim, Suk-Wha
    • Health Policy and Management
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    • v.15 no.4
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    • pp.110-135
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    • 2005
  • The objectives of this study were (1) to describe doctors' perception and attitudes toward patient safety culture and medical error reporting in their working unit and hospitals, (2) to examine whether these perception and attitudes differ by doctors' characteristics, such as sex, position, and specialties, and (3) to understand the relationship between overall perception of patient safety in their working unit and each sub domain of patient safety culture. A survey was conducted with 135 doctors working in a university hospital in Korea. After descriptive analyses and chi-square tests of subgroup differences, a multivariate-regression of overall perception of patient safety in their unit with sub-domains of patient safety culture was conducted. Overall, a significant proportion of doctors expressed negative perception of their working units' patient safety culture, many reporting potentials for patient safety problems to occur in their unit. They also negatively viewed their hospital leadership's commitment on patient safety. Regarding the patient safety in their working unit, doctors were most worried about staffing level and observance of safety procedures. Most doctors did not know how and which medical error to report. They also perceived that medical errors would work against them personally and penalize them. About 22 percent of respondents believed that even seriously harmful medical errors were not reported.

Role of a Third Extracellular Domain of an Ecotropic Receptor in Moloney Murine Leukemia Virus Infection

  • Bae Eun-Hye;Park Sung-Han;Jung Yong-Tae
    • Journal of Microbiology
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    • v.44 no.4
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    • pp.447-452
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    • 2006
  • The murine ecotropic retroviral receptor has been demonstrated to function as a mouse cationic amino acid transporter 1(mCAT1), and is comprised of multiple membranespanning domains. Feral mouse (Mus dunni) cells are not susceptible to infection by the ecotropic Moloney murine leukemia virus (MoMLV), although they can be infected by other ecotropic murine leukemia viruses, including Friend MLV and Rauscher MLV. The relative inability of MoMLV to replicate in M. dunni cells has been attributed to two amino acids $(V_{214}\;and\;G_{236})$ located within the third extracellular loop of the M. dunni CAT1 receptor (dCAT1). Via the exchange of the third extracellular loop of the mCAT1 cDNA encoding receptor from the permissive mouse and the corresponding portion of cDNA encoding for the nonpermissive M. dunni receptor, we have identified the most critical amino acid residue, which is a glycine located at position 236 within the third extracellular loop of dCAT1. We also attempted to determine the role of the third extracellular loop of the M. dunni CAT1 receptor with regard to the formation of the syncytium. The relationship between dCAT1 and virus-induced syncytia was suggested initially by our previous identification of two MLV isolates (S82F in Moloney and S84A in Friend MLV), both of which are uniquely cytopathic in M. dunni cells. In an attempt to determine the relationship existing between dCAT1 and the virally-induced syncytia, we infected 293-dCAT1 or chimeric dCAT1 cells with the S82F pseudotype virus. The S82F pseudotype virus did not induce the formation of syncytia, but did show increased susceptibility to 293 cells expressing dCATl. The results of our study indicate that S82F-induced syncytium formation may be the result of cell-cell fusion, but not virus-cell fusion.

Morphology and Mechanical Properties of Waste PVC Blends (I) -Morphology and Mechanical Properties of Waste PVC/PE Blends (폐 PVC계 고분자 블렌드의 구조 및 물성 연구(I) -폐 PVC/PE고분자 블렌드의 모폴로지 및 물성)

  • 박재찬;원종찬;최길영;이재흥;조성만;김명기
    • Polymer(Korea)
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    • v.26 no.1
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    • pp.37-44
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    • 2002
  • The polymer blends of waste polyvinyl chloride (RPVC) and waste polyethylene(RPE) were prepared by melt mixing, and their morphology and tensile properties were evaluated after the copolymers having an ethylene group in backbone and ester group in side position were added as comptatibilizers. The blend compositions were varied as follows ; RPVC/RPE 85/15 wt%, where RPVC formed a continuous phase : 50/50, mid composition : 15/85, RPE a continuous phase. The blends revealed a very low compatibility between component polymers because they showed domain sizes greater than $10\mu\textrm{m}$ over all compositions, especially the worst compatibility around mid composition. The blends showed higher compatibility when ethylene vinylacetate copolymer(EVA) and ethylene ethylacrylate-graft-methyl methacrylate copolymers(EEA-MMA) were added.

The Analysis on Research in the Korean Journal of Rehabilitation Nursing (재활간호학회지 논문 분석 - 창간호부터 2004년까지 -)

  • Lim, Nan-Young;Kim, Jeong-Hwa;Cho, Bok-Hee;So, Hee-Young;Park, Song-Ja;Cho, Nam-Ok;Yoo, Kyung-Hee
    • The Korean Journal of Rehabilitation Nursing
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    • v.8 no.2
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    • pp.119-128
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    • 2005
  • Purpose: The purpose of this study was to analyze research in the Korean Journal of Rehabilitation Nursing and to suggest further perspective for rehabilitation nursing research. Method: In this study we reviewed the contents of 134 articles published in this journal from its beginning year 1998 to 2004. Results: The majority of subjects were adult patients. The type of disease were Cerebrovascular Accident, Neuromuscular disease, Cancer patients, Urogenital disease such as Chronic Renal Failure, Spinal cord injury. Domain of research almost was client, type of research were survey(34.3%), quasi experimental study(20.9%), correlation study(19.4%). Nursing intervention of experimental study was exercise(39.0%), education(17.1%). Place of data collection was hospital (58.2%), position of researcher was professor(67.2%), method of data collection was questionnaire(50.7%). Conclusion: There has been a lack of written consent, child rehabilitation, measurement tool development, qualitative research. More studies about rehabilitation nursing are needed to extend the role and fields for professional nursing.

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