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Molecular Cloning and Functional Analysis of the Gene Encoding 3-hydroxy-3-methylglutaryl Coenzyme A Reductase from Hazel (Corylus avellana L. Gasaway)

  • Wang, Yechun;Guo, Binhui;Zhang, Fei;Yao, Hongyan;Miao, Zhiqi;Tang, Kexuan
    • BMB Reports
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    • v.40 no.6
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    • pp.861-869
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    • 2007
  • The enzyme 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR; EC1.1.1.34) catalyzes the first committed step of isoprenoids biosynthesis in MVA pathway. Here we report for the first time the cloning and characterization of a full-length cDNA encoding HMGR (designated as CgHMGR, GenBank accession number EF206343) from hazel (Corylus avellana L. Gasaway), a taxol-producing plant species. The full-length cDNA of CgHMGR was 2064 bp containing a 1704-bp ORF encoding 567 amino acids. Bioinformatic analyses revealed that the deduced CgHMGR had extensive homology with other plant HMGRs and contained two transmembrane domains and a catalytic domain. The predicted 3-D model of CgHMGR had a typical spatial structure of HMGRs. Southern blot analysis indicated that CgHMGR belonged to a small gene family. Expression analysis revealed that CgHMGR expressed high in roots, and low in leaves and stems, and the expression of CgHMGR could be up-regulated by methyl jasmonate (MeJA). The functional color assay in Escherichia coli showed that CgHMGR could accelerate the biosynthesis of $\beta$-carotene, indicating that CgHMGR encoded a functional protein. The cloning, characterization and functional analysis of CgHMGR gene will enable us to further understand the role of CgHMGR involved in taxol biosynthetic pathway in C. avellana at molecular level.

Fenobam promoted the neuroprotective effect of PEP-1-FK506BP following oxidative stress by increasing its transduction efficiency

  • Ahn, Eun Hee;Kim, Dae Won;Shin, Min Jea;Jo, Hyo Sang;Eom, Seon Ae;Kim, Duk-Soo;Park, Eun Young;Park, Jong Hoon;Cho, Sung-Woo;Park, Jinseu;Eum, Won Sik;Son, Ora;Hwang, Hyun Sook;Choi, Soo Young
    • BMB Reports
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    • v.46 no.11
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    • pp.561-566
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    • 2013
  • We examined the ways in which fenobam could promote not only the transduction of PEP-1-FK506BP into cells and tissues but also the neuroprotective effect of PEP-1-FK506BP against ischemic damage. Fenobam strongly enhanced the protective effect of PEP-1-FK506BP against $H_2O_2$-induced toxicity and DNA fragmentation in C6 cells. In addition, combinational treatment of fenobam with PEP-1-FK506BP significantly inhibited the activation of Akt and MAPK induced by $H_2O_2$, compared to treatment with PEP-1-FK506BP alone. Interestingly, our results showed that fenobam significantly increased the transduction of PEP-1-FK506BP into both C6 cells and the hippocampus of gerbil brains. Subsequently, a transient ischemic gerbil model study demonstrated that fenobam pretreatment led to the increased neuroprotection of PEP-1-FK506BP in the CA1 region of the hippocampus. Therefore, these results suggest that fenobam can be a useful agent to enhance the transduction of therapeutic PEP-1-fusion proteins into cells and tissues, thereby promoting their neuroprotective effects.

Examining the Moderating Effect of Involvement in the Internet Purchase Decision Process (인터넷 구매결정과정에서의 관여도의 조절효과에 관한 연구)

  • Kwahk, Kee-Young;Ji, So-Young
    • Asia pacific journal of information systems
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    • v.18 no.2
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    • pp.15-40
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    • 2008
  • With the explosive growth of the Internet, Internet shopping malls have become recognized as one of the major purchasing channels for consumers, as well as one of the competitive distribution channels for companies that allow them to contact with customers without intermediaries. It has motivated information systems(IS) researchers to examine the factors influencing consumer behavior and the purchase decision process in the context of Internet shopping malls. Despite the extensive research that has been conducted on the purchase decision process of consumers in online shopping malls, the results have demonstrated a need for further understanding of consumer behavior due to the unique features of virtual space and the characteristics of online consumers. Previous studies from marketing and consumer behavior domains have suggested that the concept of involvement plays an important role in explaining consumers' purchase behavior. Despite the critical role of involvement and the explosive growth of e-commerce, little research has examined the role of involvement in the Internet shopping mall context. With this motivation, this study has two research objectives. First, it introduces and tests an theoretical model capable of better explaining consumers' intention to purchase in the Internet shopping mall context. The proposed model extends and integrates existing models on purchase intention by incorporating purchase experience, innovativeness, and perceived self-control as the consumer factors, along with perceived risk, information provision, and perceived price as the Internet shopping mall factors. Second, this study examines how involvement differences may affect consumers' intention to purchase. For this purpose, two factors from involvement theory, involvement type and involvement level, are introduced into the research model as moderating variables. In order to test the proposed model, the overall approach employed was a field study using the structural equation model. We developed our data collection instrument by adopting existing validated questions wherever possible. All question items were measured with a seven-point, Likert-type scale, with anchors ranging from 'strongly disagree' to 'strongly agree.' Two IS researchers reviewed the instrument and checked its face validity. We collected empirical data for this study over a period of two weeks from subjects who had purchase experiences through Internet shopping malls. A total of 473 complete and valid responses were obtained. We carried out data analysis using a two-step methodology with AMOS 4.0. The first step in the data analysis was to establish the convergent and discriminant validity of the constructs. In the second step, we examined the structural model based on the cleansed measurement model. The empirical results partly support the proposed model and identify the moderating effect of involvement differences. Theoretical and practical implications of the study are discussed, along with its limitations.

Nucleotide Sequence, Structural Investigation and Homology Modeling Studies of a Ca2+-independent α-amylase with Acidic pH-profile

  • Sajedi, Reza Hassan;Taghdir, Majid;Naderi-Manesh, Hossein;Khajeh, Khosro;Ranjbar, Bijan
    • BMB Reports
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    • v.40 no.3
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    • pp.315-324
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    • 2007
  • The novel $\alpha$-amylase purified from locally isolated strain, Bacillus sp. KR-8104, (KRA) (Enzyme Microb Technol; 2005; 36: 666-671) is active in a wide range of pH. The enzyme maximum activity is at pH 4.0 and it retains 90% of activity at pH 3.5. The irreversible thermoinactivation patterns of KRA and the enzyme activity are not changed in the presence and absence of $Ca^{2+}$ and EDTA. Therefore, KRA acts as a $Ca^{2+}$-independent enzyme. Based on circular dichroism (CD) data from thermal unfolding of the enzyme recorded at 222 nm, addition of $Ca^{2+}$ and EDTA similar to its irreversible thermoinactivation, does not influence the thermal denaturation of the enzyme and its Tm. The amino acid sequence of KRA was obtained from the nucleotide sequencing of PCR products of encoding gene. The deduced amino acid sequence of the enzyme revealed a very high sequence homology to Bacillus amyloliquefaciens (BAA) (85% identity, 90% similarity) and Bacillus licheniformis $\alpha$-amylases (BLA) (81% identity, 88% similarity). To elucidate and understand these characteristics of the $\alpha$-amylase, a model of 3D structure of KRA was constructed using the crystal structure of the mutant of BLA as the platform and refined with a molecular dynamics (MD) simulation program. Interestingly enough, there is only one amino acid substitution for KRA in comparison with BLA and BAA in the region involved in the calcium-binding sites. On the other hand, there are many amino acid differences between BLA and KRA at the interface of A and B domains and around the metal triad and active site area. These alterations could have a role in stabilizing the native structure of the loop in the active site cleft and maintenance and stabilization of the putative metal triad-binding site. The amino acid differences at the active site cleft and around the catalytic residues might affect their pKa values and consequently shift its pH profile. In addition, the intrinsic fluorescence intensity of the enzyme at 350 nm does not show considerable change at pH 3.5-7.0.

Comparison of Head-related Transfer Function Models Based on Principal Components Analysis (주성분 분석법을 이용한 머리전달함수 모형화 기법의 성능 비교)

  • Hwang, Sung-Mok;Park, Young-Jin;Park, Youn-Sik
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.6
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    • pp.642-653
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    • 2008
  • This study deals with modeling of head-related transfer functions(HRTFs) using principal components analysis(PCA) in the time and frequency domains. Four PCA models based on head-related impulse responses(HRIRs), complex-valued HRTFs, augmented HRTFs, and log-magnitudes of HRTFs are investigated. The objective of this study is to compare modeling performances of the PCA models in the least-squares sense and to show the theoretical relationship between the PCA models. In terms of the number of principal components needed for modeling, the PCA model based on HRIR or augmented HRTFs showed more efficient modeling performance than the PCA model based on complex-valued HRTFs. The PCA model based on HRIRs in the time domain and that based on augmented HRTFs in the frequency domain are shown to be theoretically equivalent. Modeling performance of the PCA model based on log-magnitudes of HRTFs cannot be compared with that of other PCA models because the PCA model deals with log-scaled magnitude components only, whereas the other PCA models consider both magnitude and phase components in linear scale.

The Perception of Teachers in Scienced-Gifted Education, Science-Gifted Students and their Parents about Science and Scientist (영재지도교사, 영재학생 및 학부모의 과학 및 과학자에 대한 인식)

  • Sim, Byeongju;Yoon, Heesook
    • Journal of Gifted/Talented Education
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    • v.23 no.5
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    • pp.715-729
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    • 2013
  • The purpose of this study is to analyze the perception on science and scientists of the teachers who are engaged in the special education for the scientifically gifted, science-gifted students and their parents. For this study, 34 teachers, 222 students and 107 parents answered the questionnaire of the perception on science and Draw-A-Science-Test (DAST). The result showed that the three groups generally had a sound recognition but the score of recognition about a 'nature of science' was lower than other domains. The science-gifted students had less cognition about 'science and society' than their teachers and parents, but they had more positive perception about 'science learning' than their parents significantly. All of the three groups had the stereotyped image of scientist. About the internal images of scientists, three groups had a similar perception, and they showed higher scores in the cognitive aspect than emotional or ethical aspects. And the science-gifted students showed the significantly higher scores than their teachers and parents in diligence, imaginative power, concern about other people, respect for other's opinion, humor, artistic sense, respect for human, desire for peace. Three groups turned out to be influenced by movie, science journal, and biography as a source of scientist's image, but their contribution was different among groups.

An Application of Multivariate Generalizability Theory to Teacher Recommendation Letters and Self-introduction Letters Used in Selection of Mathematically Gifted Students by Observation and Nomination (관찰·추천제에 의한 수학영재 선발 시 사용되는 교사추천서와 자기소개서 평가에 대한 다변량 일반화가능도 이론의 활용)

  • Kim, Sung Yeun;Han, Ki Soon
    • Journal of Gifted/Talented Education
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    • v.23 no.5
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    • pp.671-695
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    • 2013
  • This study provides an illustrative example of using the multivariate generalizability theory. Specifically, it investigates relative effects of each error source, and finds optimal measurement conditions for the number of items within each content domain that maximizes the reliability-like coefficients, such as a generalizability coefficient and an index of dependability. The method is based on teacher recommendation letters and self-introduction letters, using an analytic scoring method in the context of selection of mathematically gifted students by observation and nomination. This study analyzed data from the 2011 academic year in the science education institute for the gifted, which is attached to the university located in the Seoul metropolitan area. It should be noted that the optimal scoring structures of this study are not generalizable to other selection instruments. However, the methodology applied in this study can be utilized to find optimal measurement conditions for the number of raters, the number of content domains, and the number of items in other selection instruments self-developed by many institutions including: the education institutes for the gifted at provincial offices of education, gifted classes, and the science education institutes for the gifted attached to universities in general. In addition, the methodology will provide bases for making informed decisions in selection instruments of the gifted based on measurement traits.

Current Trends and Recent Advances in Diagnosis, Therapy, and Prevention of Hepatocellular Carcinoma

  • Wang, Chun-Hsiang;Wey, Keh-Cherng;Mo, Lein-Ray;Chang, Kuo-Kwan;Lin, Ruey-Chang;Kuo, Jen-Juan
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.3595-3604
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    • 2015
  • Hepatocellular carcinoma (HCC) has been one of the most fatal malignant tumors worldwide and its associated morbidity and mortality remain of significant concern. Based on in-depth reviews of serological diagnosis of HCC, in addition to AFP, there are other biomarkers: Lens culinaris agglutinin-reactive AFP (AFP-L3), descarboxyprothrombin (DCP), tyrosine kinase with Ig and eprdermal growth factor (EGF) homology domains 2 (TIE2)-espressing monocytes (TEMs), glypican-3 (GPC3), Golgi protein 73 (GP73), interleukin-6 (IL-6), and squamous cell carcinoma antigen (SCCA) have been proposed as biomarkers for the early detection of HCC. The diagnosis of HCC is primarily based on noninvasive standard imaging methods, such as ultrasound (US), dynamic multiphasic multidetector-row CT (MDCT) and magnetic resonance imaging (MRI). Some experts advocate gadolinium diethyl-enetriamine pentaacetic acid (Gd-EOB-DTPA) MRI and contrast-enhanced US as the promising imaging madalities of choice. With regard to recent advancements in tissue markers, many cuting-edge technologies using genome-wide DNA microarrays, qRT-PCR, and proteomic and inmunostaining studies have been implemented in an attempt to identify markers for early diagnosis of HCC. Only less than half of HCC patients at initial diagnosis are at an early stage treatable with curative options: local ablation, surgical resection, or liver transplant. Transarterial chemoembolization (TACE) is considered the standard of care with palliation for intermediate stage HCC. Recent innovative procedures using drug-eluting-beads and radioembolization using Yttrium-90 may exhibit beneficial effects in HCC treatment. During the past few years, several molecular targeted agents have been evaluated in clinical trials in advanced HCC. Sorafenib is currently the only approved systemic treatment for HCC. It has been approved for the therapy of asymptomatic HCC patients with well-preserved liver function who are not candidates for potentially curative treatments, such as surgical resection or liver transplantation. In the USA, Europe and particularly Japan, hepatitis C virus (HCV) related HCC accounts for most liver cancer, as compared with Asia-Pacific regions, where hepatitis B virus (HBV) may play a more important role in HCC development. HBV vaccination, while a vaccine is not yet available against HCV, has been recognized as a best primary prevention method for HBV-related HCC, although in patients already infected with HBV or HCV, secondary prevention with antiviral therapy is still a reasonable strategy. In addition to HBV and HCV, attention should be paid to other relevant HCC risk factors, including nonalcoholic fatty liver disease due to obesity and diabetes, heavy alcohol consumption, and prolonged aflatoxin exposure. Interestingly, coffee and vitamin K2 have been proven to provide protective effects against HCC. Regarding tertiary prevention of HCC recurrence after surgical resection, addition of antiviral treatment has proven to be a rational strategy.

Development of a Performance Reference Model (PRM) for Ubiquitous City Operations (U-City 전략 성과 참조모델로서의 운영성과 측정 지표체계 개발에 대한 연구)

  • Park, Dong-Wan;Lee, Jung-Hoon;Kim, Jae-Min
    • The Journal of Society for e-Business Studies
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    • v.15 no.3
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    • pp.25-44
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    • 2010
  • In recent years, Ubiquitous City (u-City), the integrated and convergence of ubiquitous services, infrastructure, technologies and city management of the new future development city, is being initiated by the Korean government and local authorities as their new national growth engine. However, a performance measurement system for evaluating and monitoring the impacts of U-City implementation is yet to be established. This paper aims to develop an integrated performance management system (PMS) and extensively used as a tool for managing performance activities to support the visions and goals of the u-City operations. Based on current reviews on the literature and interviews with experts drew Critical Success Factors (CSF) and Key Performance Indicators (KPI) by four different measurement domains including U-City services, infrastructure, technologies, management and developed into an integrated performance measurement system based on the Balanced Scored Card (BSC) perspective. The system also provides number of examples of 'u-City Strategy Map' which illustrates a causal relationship between CSFs to execute u-City visions and goals.

A Comparative Study on Health Promotion Behaviors by Complementary Alternative Therapy Utilization of Elderly Women with Osteoarthritis (퇴행성관절염 여성노인들의 보완대체요법 이용 유무에 따른 건강증진행위 비교)

  • Kim, Jeong-Suk;Park, Jeong-Sook
    • Journal of Digital Convergence
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    • v.16 no.2
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    • pp.451-459
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    • 2018
  • The aim of this study is to compare the differences in health promotion behaviors by the use of complementary alternative therapy(CAT) in elderly women with osteoarthritis. A total of 621 elderly women with osteoarthritis from public health centers and their branches at a city of C state were enrolled. This study analyzed the frequency and percentage of complementary alternative therapy utilization; a Chi-square test was used for utilization analysis according to subjects' general characteristics and disease features. Degree of health promotion behaviors according to CAT utilization was analyzed by a t-test and ANOVA. The study found that the CAT utilization rate for the total of 621 people was 61.7 %. For health promotion behaviors according to CAT utilization, statistically significant differences were found in exercise (p<0.001), health responsibility (p<0.001) and self-realization (p=0.016) from the domains. This study demonstrated the differences of health promotion behaviors based on CAT utilization. Due to the results of this study it is notable to mention that counseling, instruction for CAT utilization, and strategy development for health promotion are necessary for elderly women with osteoarthritis.