• 제목/요약/키워드: A375-S2

검색결과 385건 처리시간 0.025초

BACE2의 대량발현 및 리폴딩 (Overexpression and Refolding of BACE2)

  • 박선주;타이슈아이치;이연지;전유진;김용태
    • 한국수산과학회지
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    • 제47권4호
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    • pp.370-375
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    • 2014
  • BACE2 is a membrane-bound aspartic protease that is highly homologous with BACE1. While BACE1 processes the amyloid precursor protein (APP) at a key step in generating ${\beta}$-amyloid peptide and presumably causes Alzheimer's disease (AD), BACE2 has not been demonstrated to be involved in APP processing directly, and its physiological functions are unknown. To determine its function and to develop inhibitors from marine sources, we constructed an overexpression vector for producing BACE2. The gene encoding human BACE2 protease was amplified using the polymerase chain reaction and cloned into the pET11a expression vector, resulting in pET11a/BACE2. Recombinant BACE2 protease was overexpressed successfully in E. coli as inclusion bodies, refolded using the rapid-dilution method, and purified via two-step fast protein liquid chromatography using Sephacryl S-300 gel filtration and Resource-Q column chromatography. The BACE2 protease produced was an active form. This study provides an efficient method not only for studying the basic properties of BACE2, but also for developing inhibitors from natural marine sources.

Zr계 비정질 복상 합금의 과냉 액상 영역에서의 유동 음력과 변형거동 (Flow Stress and Deformation Behavior of Zr-based Bulk Metallic Glass Composite in Supercooled Liquid Region)

  • 전현준;이광석;장영원
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2006년도 춘계학술대회 논문집
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    • pp.417-420
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    • 2006
  • The composition and structure of dendrite phase within $Zr_{76.11}Ti_{4.20}Cu_{4.51}Ni_{3.16}Be_{1.49}Nb_{10.53}$ bulk metallic glass (BMG) were confirmed by using an EPMA, XRD and TEM, respectively. The chief elements of dendrite phase were Zr-Ti-Nb and had a BCC structure. The thermal properties of this BMG have been then subsequently investigated by using a differential scanning calorimeter (DSC). The glass transition and crystallization onset temperatures were determined as $339.7^{\circ}C$ and $375.8^{\circ}C$ for this alloy, respectively. Mechanical properties have also been examined by conducting a series of uniaxial compression tests at various temperatures within supercooled liquid region under the strain rates between $10^{-4}/s$ and $3{\times}10^{-2}/s$. The deformation behavior of BMG composite within supercooled liquid region is similar to one of Vit-1 exhibiting amorphous single phase alloy. The flow stresses of BMG composite, however, are entirely higher than those of Vit-1 because dendrite phases are interfere with moving of atoms.

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단삼추출물의 Src-family Kinase 억제에 의한 항앨러지 효과 (Salviae Radix Suppresses Mast Cell-mediated Allergic Response: Inhibition of Src-family Kinase)

  • 김영미
    • 약학회지
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    • 제52권5호
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    • pp.370-375
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    • 2008
  • In this study, the anti-allergic activity and mechanim of Salviae radix (SR) were investigated. The ethanol extract of SR showed significant inhibitory effect on degranulation from antigen-stimulated mast cells and it also inhibited the expression and secretion of TNF-${\alpha}$ and IL-4 in antigen-stimulated RBL-2H3 cells. In the mast cell-mediated local animal allergy model, it suppressed the passive cutaneous anaphylaxis in a dose-dependent manner. As its mechanism of action, SR inhibited the activating phosphorylation of Syk, a downstream signaling molecule of Src-family kinase, for the activation of mast cells. The results of the study indicate that the anti-allergic activity of SR is mediated by the inhibition of Src-family kinase in mast cells.

NEMA NU2-2001을 이용한 PET-CT 스캐너의 물리적 특성평가 (Evaluation of Physical Characteristics of Discovery ST scanner Using NEMA NU2-2001 Standard)

  • 이병일
    • 통합자연과학논문집
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    • 제1권2호
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    • pp.79-83
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    • 2008
  • As a new standard for performance measurement, NEMA NU2-2001 was presented recently. In this study, I investigated the spatial resolution, sensitivity, scatter fraction, and noise equivalent count ratio (NECR) in order to know the information of physical characteristics and system performance of GE discovery ST using this new standard. Bismuth germinate crystals ($6{\times}6$ array, $6.3mm{\times}6.3mm{\times}30mm$) were used in discovery ST (energy window:375-650 keV, coincidence window:11.7 nsec). To measure the sensitivity, five aluminum sleeves (Data Spectrum Corp., Chapel Hill, NC., USA, thickness:1.25 mm)-NEMA sensitivity phantom- filled with F-18 solution were used. Successive measurements in 2D and 3D acquisition mode were made with a line source at the center of transaxial field of view and 10 cm off from the center until the count was over 500,000. Spatial resolution was estimated using a point source (F-18, 0.1 mCi) at different locations in the FOV. Scatter fraction and NECR was tested using a NEMA scatter phantom. Dynamic data were acquired for 7 half-lives using F-18 solution. And true to background ratio was averaged at last three frames when the random rate was as small as ignorable for the calculation of scatter fraction. We anticipate this overall evaluated results could be used for the quality assurance and optimized image acquisition for clinical research.

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자취와 자택거주 간호대생의 건강증진생활양식에 관한 연구 (A Study on Health Promotion Lifestyles between College Nursing Students Who Live with Parents and Self-Boarding)

  • 유경희
    • 한국간호교육학회지
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    • 제17권2호
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    • pp.306-316
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    • 2011
  • Purpose: The purpose of this study was to compare health promotion lifestyles of college nursing students between students who live with their parents and students who are self-boarders. Methods: The sample consisted of 375 college nursing students in C and S city. Self report questionnaires were used to measure the variables. In data analysis, the SPSSWIN 18.0 program was utilized for descriptive statistics, Pearson's correlation coefficients, and multiple regression analysis. Results: The mean score for Health Promotion Lifestyle in living with the parents group was significantly higher than that of the self-boarders group (t=-2.16, p=.031). In multiple regression, perceived health state, exercise frequency, self-rated knowledge about health, and grade were significant predictors of Health Promotion Lifestyle in college nursing students, explaining 26.3%. Conclusion: This study suggests that perceived health state, exercise frequency, and self-rated knowledge about health, and grade are significant influencing factors in Health Promotion Lifestyle in college nursing students. Therefore, strategies which improve these variables must be developed for college nursing students.

한국 청소년의 스마트폰 사용과 구강질환 증상과의 관련성 (Relationship between hours of smartphone use and oral disease symptoms in Korean adolescents)

  • 김선숙;윤혜정
    • 한국치위생학회지
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    • 제23권6호
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    • pp.529-536
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    • 2023
  • Objectives: This study aimed to determine the relationship between hours of smartphone use and oral disease symptoms in Korean adolescents. Methods: In this study, data from the 2022 Youth Health Behavior Online Survey were used. The final analysis was conducted on students who responded that they have used a smartphone (N=50,375). Chi-squared test and multivariate logistic regression analysis were used to analyze the relationship between oral disease symptoms and smartphone use time (p<0.05). Results: Consequent to examining the effect of smartphone use on oral disease symptoms, it was found that oral symptoms, such as pain during chewing and tingling throbbing, increased as smartphones were used for >4 h (p<0.05). Additionally, oral symptoms, such as gingivalgia bleeding and bad breath, appeared to increase as smartphones were used for >6 h (p<0.05). However, using smartphones for <0-2 h or 2-4 h had no effect on oral disease symptoms. Conclusions: In adolescents, oral disease symptoms increased significantly with increasing hours of smartphone use. Therefore, adolescents should be guided so that they use smartphones for <2 h or >4 h. Moreover, guidance on forming the habit of tooth brushing after eating food should be provided to prevent oral disease symptoms.

분할에 의한 네트워크의 국간신뢰도 계산 (Source to teminal reliability evaluation by network decomposition)

  • 서희종;최종수
    • 한국통신학회논문지
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    • 제21권2호
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    • pp.375-382
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    • 1996
  • 본 논문에서는 네트워크를 분할하여 국간신뢰도를 계산하는 효과적인 방법이 기술된다. 네트워크를 그래프로 모델화하고 그 그래프를 2개의 부분그래프로 부분그래프로 분할한다. 한 부분 그래프의 논리적항을 계산하고 논리 적항을 갖는 사상에 따라서 다른 부분그래프의 그래프를 만들고 논리적항을 계산한다. 부분그래프의 논리적항을 서로 곱해서 국간신뢰도를 계산하는 방법을 제안한다. 한 부분그래프의 모든 논리적항은 2의 그 부분그래프가 갖는 가지 수 제곱으로 계산되고 다른 부분그래프의 그래프가 갖는 논리적항은 그래프가 갖는 가지 수와 논리적항 수의 곱으로 계산할 수 있다. 이 방법은 분할하지 않고 국간 신뢰도를 계산하는 방법에 비해서 적은 계산시간을 갖는다.

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PET/CT에서 Pitch와 Rotation Time의 변화를 이용한 능동적인 프로토콜 사용에 대한 연구 (A Study on the Use of Active Protocol Using the Change of Pitch and Rotation Time in PET/CT)

  • 장의순;곽인석;박선명;최춘기;이혁;김수영;최성욱
    • 핵의학기술
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    • 제17권2호
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    • pp.67-71
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    • 2013
  • PET/CT검사에서 CT촬영조건의 변화는 영상의 화질 및 환자가 받는 피폭선량에 영향을 미친다. 본 연구는 CT 매개 변수 중 Pitch와 X-선관 회전시간 변화에 따른 선량대비 CT 영상의 질과 이로 인해 PET상에서 SUV에 미치는 영향을 비교 평가하고자 하였다. Discovery STe PET/CT 장비를 이용하여 영상을 획득하였다. QA Phantom과 AAPM Phantom을 이용한 CT 영상 획득 시 Pitch는 0.562, 0.938, 1.375, 1.75:1로 4단계, X-선관 회전시간은 0.5에서 1.0까지 0.1초씩 증가시켜 6단계로 나누어 총 24개 조합을 적용한 영상을 각각 획득하였다. PET 영상은 $^{18}F-FDG$ 5.3 kBq/mL가 채워진 1994 NEMA PET Phantom을 이용하여 프레임당 2분 30초의 방출영상을 획득하였다. 각 조합의 CT 영상에 관심영역을 설정하고 CT number의 표준편차를 측정하였다. 동일한 영상에서 DLP변화에 따른 영상잡음의 예측값을 계산하여 예측값 대비 실측값의 비율을 구해 선량대비 영상잡음 효과를 비교하는 척도로 사용하였다. AAPM Phantom 영상에서 1.0 mm까지 식별이 가능한 지 확인하였다. NEMA PET Phantom의 방출영상에 관심영 역을 설정하고 SUV를 비교 평가하였다. Pitch가 0.562, 0.938, 1.375, 1.75:1로 변화할 때 영상잡음 효과는 QA Phantom에서 1.00, 1.03, 1.01, 0.96, AAPM Phantom에서 1.00, 1.04, 1.02, 0.97로 측정되었다. 회전시간의 증가에 따른 경우 QA Phantom에서 0.99, 1.02, 1.00, 1.00, 0.99, 0.99이었고, AAPM Phantom에서 1.01, 1.01, 0.99, 1.01, 1.01, 1.01로 SPSS Ver. 18을 이용하여 상관관계를 분석한 결과 피어슨 상관계수는 -0.059로 나타났다. 공간분해능에 대한 평가는 24개의 조합 모두에서 1.0 mm까지 육안으로 구별이 가능하였다. SUV의 경우 평균 SUV는 모든 조합에서 1.1로 모두 동일한 값을 나타내었다. Pitch 변화에 따른 CT 영상 평가에서 1.75:1을 적용 시 선량대비 가장 적은 영상잡음 효과를 보이며 공간분해능과 SUV에는 영향을 미치지 않는다. 그러나 회전시간 변화가 영상에 미치는 영향에는 유의한 차이가 없음을 알 수 있다. 결과에서와 같이 각 장비에 따른 선량대비 영상잡음이 적은 Pitch를 사용하고 환자의 체격에 따른 적절한 X-선관 회전시간을 이용한다면 환자의 피폭선량을 줄이면서 최적의 화질을 얻을 수 있는 프로토콜을 구성하는데 도움이 될 것이라 사료된다.

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비폭력대화프로그램이 간호사의 대인관계능력, 직무스트레스, 정신적 웰니스에 미치는 효과 (The Effect of Nonviolent Communication Program on Nurse's Interpersonal Competence, Job Stress and Spiritual Wellness)

  • 심봉희;이영숙;안성아
    • 한국산학기술학회논문지
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    • 제17권9호
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    • pp.375-386
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    • 2016
  • 본 연구는 비폭력대화프로그램이 간호사의 대인관계능력, 직무 스트레스, 정신적 웰니스에 미치는 효과를 규명하기 위한 비동등성 대조군 전후 시차설계인 유사실험연구이다. 연구기간은 2013년 6월1일부터 10월20일이며, 자료수집은 J시에 소재한 G병원에 근무하는 간호사를 대상으로 실험군14명, 대조군 15명으로 총 29명이었다. 본 연구는 대학병원 간호사들을 대상으로 6주간 진행하였고, 간호사의 근무특성상 1주에 3회기를 진행하였으며, 각 회기 당 소요된 시간은 60분이었으며, 대조군에게는 프로그램을 진행하지 않았다. 자료분석은 빈도와 백분율, 카이제곱검증, Fisher's exact t-test로 분석하였다. 대화 프로그램을 적용한 후 간호사의 대인관계능력, 직무스트레스, 정신적 웰니스에 미치는 효과를 검증하였으며 그 결과는 다음과 같다. 첫째, 비폭력대화프로그램에 참여한 간호사들은 대인관계 능력은 시기와 집단 간의 교호작용은 유의하게 나타났다(F=7.726, p=0.002). 둘째, 비폭력대화프로그램에 참여한 간호사들의 직무스트레스 수준은 시기와 집단 간의 교호작용은 유의하게 나타나지 않았다(F=0.142, p=0.851). 셋째, 비폭력대화프로그램에 참여한 간호사들은 정신적 웰니스는 시기와 집단간의 교호작용은 유의하게 나타났다(F=31.355, p=0.000). 결론적으로 비폭력대화프로그램은 임상간호사들의 대인관계능력과 정신적 웰니스를 증진하는데 효과적임을 확인하였으나 직무스트레스에 대해서는 효과가 없는 것으로 나타나 추후반복연구가 시행되어야할 것이다.

RNAi Suppression of RPN12a Decreases the Expression of Type-A ARRs, Negative Regulators of Cytokinin Signaling Pathway, in Arabidopsis

  • Ryu, Moon Young;Cho, Seok Keun;Kim, Woo Taek
    • Molecules and Cells
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    • 제28권4호
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    • pp.375-382
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    • 2009
  • The 26S proteasome is a 2-MDa complex with a central role in protein turn over. The 26S proteasome is comprised of one 20S core particle and two 19S regulatory particles (RPs). The RPN12a protein, a non-ATPase subunit of the 19S RP, was previously shown to be involved in cytokinin signaling in Arabidopsis. To further investigate cellular roles of RPN12a, RNAi transgenic plants of RPN12a were constructed. As expected, the 35S:RNAi-RPN12a plants showed cytokinin signaling defective phenotypes, including abnormal formation of leaves and inflorescences. Furthermore, RNAi knock-down transgenic plants exhibited additional unique phenotypes, including concave and heart-shape cotyledons, triple cotyledons, irregular and clustered guard cells, and defects in phyllotaxy, all of which are typical for defective cytokinin signaling. We next examined the mRNA level of cytokinin signaling components, including type-A ARRs, type-B ARRs, and CRFs. The expression of type-A ARRs, encoding negative regulators of cytokinin signaling, was markedly reduced in 35S:RNAi-RPN12a transgenic plants relative to that in wild type plants, while type-B ARRs and CRFs were unaffected. Our results also indicate that in vivo stability of the ARR5 protein, a negative regulator of cytokinin signaling, is mediated by the 26S proteasome complex. These results suggest that RPN12a participates in feedback inhibitory mechanism of cytokinin signaling through modulation of the abundance of ARR5 protein in Arabidopsis.