http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Xp-tree : Xpath 로케이션 스텝의 효율화를 위한 새로운 공간기반의 인덱싱 기법
Nguyen Van Trang(Nguyen Van Trang),황정희(Jeong Hee Hwang),류근호(Keun Ho Ryu) 한국정보과학회 2004 한국정보과학회 학술발표논문집 Vol.31 No.1B
Nowadays, with the rapid emergence of XML as a standard for data exchange over the Internet had led to considerable interest in the problem of data management requirements such as the need to store and query XML documents in which the location path languages Xpath is of particular important for XML application since it is a core component of many XML processing standards such as XSLT or XQuery. This paper gives a brief overview about method and design by applying a new spatial-based indexing method namely Xp-tree that used for supporting Xpath. Spatial indexing technique has been proved its capacity on searching in large databases. Based on accelerating a node using planar as combined with the numbering schema, we devise efficiently derivative algorithms, which are simple, but useful. Besides that, it also allows to trace all its relative nodes of context node in a manner supporting queries natural to the types especially Xpath queries with predicates.
Hoang, Van-Hai,Ngo, Van T. H.,Cui, Minghua,Manh, Nguyen Van,Tran, Phuong-Thao,Ann, Jihyae,Ha, Hee-Jin,Kim, Hee,Choi, Kwanghyun,Kim, Young-Ho,Chang, Hyerim,Macalino, Stephani Joy Y.,Lee, Jiyoun,Choi, S American Chemical Society 2019 Journal of medicinal chemistry Vol.62 No.17
<P>Alzheimer’s disease (AD) is an incurable, progressive neurodegenerative disease whose pathogenesis cannot be defined by one single element but consists of various factors; thus, there is a call for alternative approaches to tackle the multifaceted aspects of AD. Among the potential alternative targets, we aim to focus on glutaminyl cyclase (QC), which reduces the toxic pyroform of β-amyloid in the brains of AD patients. On the basis of a putative active conformation of the prototype inhibitor <B>1</B>, a series of N-substituted thiourea, urea, and α-substituted amide derivatives were developed. The structure-activity relationship analyses indicated that conformationally restrained inhibitors demonstrated much improved QC inhibition in vitro compared to nonrestricted analogues, and several selected compounds demonstrated desirable therapeutic activity in an AD mouse model. The conformational analysis of a representative inhibitor indicated that the inhibitor appeared to maintain the Z-E conformation at the active site, as it is critical for its potent activity.</P> [FIG OMISSION]</BR>
Hoang, Van-Hai,Tran, Phuong-Thao,Cui, Minghua,Ngo, Van T. H.,Ann, Jihyae,Park, Jongmi,Lee, Jiyoun,Choi, Kwanghyun,Cho, Hanyang,Kim, Hee,Ha, Hee-Jin,Hong, Hyun-Seok,Choi, Sun,Kim, Young-Ho,Lee, Jeewoo American Chemical Society 2017 Journal of medicinal chemistry Vol.60 No.6
<P>Glutaminyl cyclase (QC) has been implicated in the formation of toxic amyloid plaques by generating the N-terminal pyroglutamate of beta-amyloid peptides (pGlu-A beta) and thus may participate in the pathogenesis of Alzheimer's disease (AD). We designed a library of glutamyl cyclase (QC) inhibitors based on the proposed binding mode of the preferred substrate, A beta 3E-42. An in vitro structure-activity relationship study identified several excellent QC inhibitors demonstrating 5- to 40-fold increases in potency compared to a known QC inhibitor. When tested in mouse models of AD, compound 212 significantly reduced the brain concentrations of pyroform A beta and total A beta and restored cognitive functions. This potent A beta-lowering effect was achieved by incorporating an additional binding region into our previously established pharmacophoric model, resulting in strong-interactions with the carboxylate group of Glu327 in the QC binding site. Our study offers useful insights in designing novel QC inhibitors as a potential treatment option for AD.</P>
Ngo, Van T.H.,Hoang, Van-Hai,Tran, Phuong-Thao,Ann, Jihyae,Cui, Minghua,Park, Gyungseo,Choi, Sun,Lee, Jiyoun,Kim, Hee,Ha, Hee-Jin,Choi, Kwanghyun,Kim, Young-Ho,Lee, Jeewoo Elsevier 2018 Bioorganic & medicinal chemistry Vol.26 No.5
<P><B>Abstract</B></P> <P>Pyroglutamate-modified amyloid β peptides (pGlu-Aβ) are highly neurotoxic and promote the formation of amyloid plaques. The pGlu-Aβ peptides are generated by glutaminyl cyclase (QC), and recent clinical studies indicate that QC represents an alternative therapeutic target to treat Alzheimer’s disease (AD). We have previously developed a series of QC inhibitors with an extended pharmacophoric scaffold, termed the Arg-mimetic D-region. In the present study, we focused on the structure activity relationship (SAR) of analogues with modifications in the D-region and evaluated their biological activity. Most compounds in this series exhibited potent activity in vitro, and our SAR analysis and the molecular docking studies identified compound <B>202</B> as a potential candidate because it forms an additional hydrophobic interaction in the <I>h</I>QC active site. Overall, our study provides valuable insights into the Arg-mimetic pharmacophore that will guide the design of novel QC inhibitors as potential treatments for AD.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Ngo, Van T.H.,Hoang, Van-Hai,Tran, Phuong-Thao,Van Manh, Nguyen,Ann, Jihyae,Kim, Eunhye,Cui, Minghua,Choi, Sun,Lee, Jiyoun,Kim, Hee,Ha, Hee-Jin,Choi, Kwanghyun,Kim, Young-Ho,Lee, Jeewoo Elsevier 2018 Bioorganic & medicinal chemistry Vol.26 No.12
<P><B>Abstract</B></P> <P>Glutamyl cyclase (QC) is a promising therapeutic target because of its involvement in the pathogenesis of Alzheimer’s disease. In this study, we developed novel QC inhibitors that contain 3-aminoalkyloxy-4-methoxyphenyl and 4-aminoalkyloxyphenyl groups to replace the previously developed pharmacophore. Several potent inhibitors were identified, showing IC<SUB>50</SUB> values in a low nanomolar range, and were further studied for <I>in vitro</I> toxicity and <I>in vivo</I> activity. Among these, inhibitors <B>51</B> and <B>53</B> displayed the most potent Aβ<SUB>N3pE−40</SUB>-lowering effects in <I>in vivo</I> acute model with reasonable BBB penetration, without showing cytotoxicity and <I>h</I>ERG inhibition. The molecular modeling analysis of <B>53</B> indicated that the salt bridge interaction and the hydrogen bonding in the active site provided a high potency. Given the potent activity and favorable BBB penetration with low cytotoxicity, we believe that compound <B>53</B> may serve as a potential candidate for anti-Alzheimer’s agents.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>
Van, Mien,Kang, Hee-Jun Professional Engineering Publishing Ltd 2016 Proceedings of the Institution of Mechanical Engin Vol. No.
<P>This paper presents an automatic fault diagnosis of different rolling element bearing faults using a dual-tree complex wavelet transform, empirical mode decomposition, and a novel two-stage feature selection technique. In this method, dual-tree complex wavelet transform and empirical mode decomposition were used to preprocess the original vibration signal to obtain more accurate fault characteristic information. Then, features in the time domain were extracted from each of the original signals, the coefficients of the dual-tree complex wavelet transform, and some useful intrinsic mode functions to generate a rich combined feature set. Next, a two-stage feature selection algorithm was proposed to generate the smallest set of features that leads to the superior classification accuracy. In the first stage of the two-stage feature selection, we found the candidate feature set using the distance evaluation technique and a k-nearest neighbor classifier. In the second stage, a genetic algorithm-based k-nearest neighbor classifier was designed to obtain the superior combination of features from the candidate feature set with respect to the classification accuracy and number of feature inputs. Finally, the selected features were used as the input to a k-nearest neighbor classifier to evaluate the system diagnosis performance. The experimental results obtained from real bearing vibration signals demonstrated that the method combining dual-tree complex wavelet transform, empirical mode decomposition, and the two-stage feature selection technique is effective in both feature extraction and feature selection, which also increase classification accuracy.</P>