Discriminative multi-task feature selection for multi-modality classification of Alzheimer’s disease

Ye, T.,Zu, C.,Jie, B.,Shen, D.,Zhang, D.,the, A. s. SPRINGER SCIENCE AND BUSINESS MEDIA 2016 BRAIN IMAGING AND BEHAVIOR Vol.10 No.3

<P>Recently, multi-task based feature selection methods have been used in multi-modality based classification of Alzheimer's disease (AD) and its prodromal stage, i.e., mild cognitive impairment (MCI). However, in traditional multi-task feature selection methods, some useful discriminative information among subjects is usually not well mined for further improving the subsequent classification performance. Accordingly, in this paper, we propose a discriminative multi-task feature selection method to select the most discriminative features for multi-modality based classification of AD/MCI. Specifically, for each modality, we train a linear regression model using the corresponding modality of data, and further enforce the group-sparsity regularization on weights of those regression models for joint selection of common features across multiple modalities. Furthermore, we propose a discriminative regularization term based on the intra-class and inter-class Laplacian matrices to better use the discriminative information among subjects. To evaluate our proposed method, we perform extensive experiments on 202 subjects, including 51 AD patients, 99 MCI patients, and 52 healthy controls (HC), from the baseline MRI and FDG-PET image data of the Alzheimer's Disease Neuroimaging Initiative (ADNI). The experimental results show that our proposed method not only improves the classification performance, but also has potential to discover the disease-related biomarkers useful for diagnosis of disease, along with the comparison to several state-of-the-art methods for multi-modality based AD/MCI classification.</P>

Fully automated segmentation of cartilage from magnetic resonance images using improved 3D shape context and active shape model

Ye, T.,Cui, X.,Kim, H. Published for the Society by Baillère Tinda 2015 OSTEOARTHRITIS AND CARTILAGE Vol.23 No.suppl2

Model-Based Control to Enhance a Novel Two Dimensional Positioning System

Chan Yet Wong,Carlos Montes,Laine Mears,John Ziegert 제어로봇시스템학회 2010 제어로봇시스템학회 국제학술대회 논문집 Vol.2010 No.10

This paper presents a model-based control algorithm to address the delayed feedback that occurs in a novel two dimensional positioning system. The delayed feedback causes the motion control system unable to track the desire setpoint accurately and at the same time introduce following error. Thus, a Modified Smith Predictor is proposed to address the delayed feedback by having an inner plant model to predict the path during the delay. Furthermore, an online system identification scheme is proposed to improve the accuracy of the model used in Modified Smith Predictor. Simulation and experimental results of the Modified Smith Predictor and online system identification are presented

Powder Preparation by Hydroxide Coprecipitation and Phase Development of Pb0.97La0.02(Zr0.64Sn0.25Ti0.11)O3 Ceramics

Lee, Joon-Hyung,Chiang, Yet-Ming The Korean Ceramic Society 1998 The Korean journal of ceramics Vol.4 No.3

A homogeneous and stoichimetric fine powder of the ferroelectric $Pb_[0.97}La_{0.02}(Zr_{0.64}Sn_{0.25}Ti_{0.11})O_3$ (PLZST) has been prepared by the hydroxide coprecipitation method. Studies on the crystallization behavior of precursor as a function of temperature by X-ray powder diffraction and transmission electron microscopy technique were consistent with the formation of the pyrochlore phase from amorphous, initially at low temperatures around 500~$550^{\circ}C$. Further heat treatment up to $750^{\circ}C$ resulted in development of the perovskite phase with no significant pyrochlore crystallite growth. At intermediate temperatures the precursor yields a fine mixture of pyrochlore and perovskite phases. When the pyrochlore phase was heat teated in air, slight weight increase was observed in the temperature range of 300~$700^{\circ}C$, which is thought to be caused from oxygen absorption. In argon atmosphere, weight increase was not observed. On the other hand, weight loss began to occur near $700^{\circ}C$, with giving off mostly CO2 gas. This implies that the pyrochlore phase seems to be crystallorgraphycally and thermodynamically metastable. An apparent activation energy of 53.9 ㎉/mol was estimated for the pyrochlore-perovskite phase transformation.

A salt-regulated peptide derived from the CAP superfamily protein negatively regulates salt-stress tolerance in <i>Arabidopsis</i>

Chien, Pei-Shan,Nam, Hong Gil,Chen, Yet-Ran Oxford University Press 2015 Journal of experimental botany Vol.66 No.17

<P>High salinity has negative impacts on plant growth through altered water uptake and ion-specific toxicities. Plants have therefore evolved an intricate regulatory network in which plant hormones play significant roles in modulating physiological responses to salinity. However, current understanding of the plant peptides involved in this regulatory network remains limited. Here, we identified a salt-regulated peptide in <I>Arabidopsis</I>. The peptide was 11 aa and was derived from the C terminus of a <I>c</I>ysteine-rich secretory proteins, <I>a</I>ntigen 5, and <I>p</I>athogenesis-related 1 proteins (CAP) superfamily. This peptide was found by searching homologues in <I>Arabidopsis</I> using the precursor of a tomato CAP-derived peptide (CAPE) that was initially identified as an immune signal. In searching for a CAPE involved in salt responses, we screened CAPE precursor genes that showed salt-responsive expression and found that the <I>PROAtCAPE1</I> (<I>AT4G33730</I>) gene was regulated by salinity. We confirmed the endogenous <I>Arabidopsis</I> CAP-derived peptide 1 (AtCAPE1) by mass spectrometry and found that a key amino acid residue in PROAtCAPE1 is critical for AtCAPE1 production. Moreover, although <I>PROAtCAPE1</I> was expressed mainly in the roots, AtCAPE1 was discovered to be upregulated systemically upon salt treatment. The salt-induced AtCAPE1 negatively regulated salt tolerance by suppressing several salt-tolerance genes functioning in the production of osmolytes, detoxification, stomatal closure control, and cell membrane protection. This discovery demonstrates that AtCAPE1, a homologue of tomato immune regulator CAPE1, plays an important role in the regulation of salt stress responses. Our discovery thus suggests that the peptide may function in a trade-off between pathogen defence and salt tolerance.</P>

Expression and Identification of p90 as the Murine Mitochondrial Glycerol-3-phosphate Acyltransferase

Lee,Sunjoo,Sul,Hei Sook,Hahm,Young Tae,Yet,Shaw-Fang 濟州大學校 基礎科學硏究所 1993 基礎科學硏究 Vol.6 No.1

Glycerol-3-phosphate acyltransferase (GPAT) catalyzes the initial and committed step in glycerolipid biosynthesis. Mitochondrial GPAT, unlike the microsomal isozyme, prefers saturated fatty acids as a substrate. We have recently reported cloning of a cDNA to an unidentified 6.8-kb mRNA by a differential hybridization. The mRNA contains an open reading frame of 827 amino acids (p90) with 30% sequence homology in a 300 amino acid stretch to Escherichia coli GPAT. The 6.8-kb mRNA was induced dramatically when fasted mice were refed a high-carbohydrate diet. Here, we have expressed the open reading frame as trpE fusion proteins and used them to generate antibodies. The antibodies recognized a polypeptide of 90 kDa (p90) when the 6.8-kb cDNA sequence was used for in vitro transcription and translation. By Western blot analysis using these antibodies, we detected p 90 in mitochondrial fractions of lever, and the p90 level was increased by refeeding. The increase in the p90 level correlated with the increase in mitochondrial GPAT activity. Moreover, p90 was not detectable in 3T3-LI preadipocytes but markedly increased during aidpose conversion. This increase was consistent with the 11-fold increase we observed in N-ethylmaleimide (NEM)-resistant mitochondrial GPAT activity during adipocyte differentiation. In addition, we have expressed p90 in CHO cells by stable transfection. The transfected genes in both correct and reverse orientations produced distinct 3.9-kb transcripts owing to the truncation of a part of the noncoding regions of the endogenous 6.8-kb mRNA befor insertion into the pMSXND vector. The transfected CHO cells were treated with 2-aminopurine, an agent that increases expression of cxogenous gencs. There was a 6-fold increase in the p90 level in mitochondria of the CHO cells transfected with the p90 sequence in the correct orientation, and the activity of the NEM-resistant mitochondrial GPAT also increased accordingly. Moreover, the mitochondrial GPAT of the transfected cells preferred palmitoyl CoA as a substrate over oleoyl CoA. The above correlation between the level of p90 expression and GPAT activity in mitochondrial GPAT. and the substrate specificity of the expressed enzyme show evidence that p90 is the murine mitochondrial GPAT. We have also demonstrated here that the changes in mitochondrial GPAT activity during different nutritional and developmental conditions are due primarily to the changes in enzyme concentration, and not to modulation of the catalytic activity of the existing enzyme.

Quantitative Peptidomics Study Reveals That a Wound-Induced Peptide from PR-1 Regulates Immune Signaling in Tomato

Chen, Ying-Lan,Lee, Chi-Ying,Cheng, Kai-Tan,Chang, Wei-Hung,Huang, Rong-Nan,Nam, Hong Gil,Chen, Yet-Ran American Society of Plant Biologists 2014 The Plant cell Vol.26 No.10

<P>CAPE1, a conserved peptide elicitor derived from tomato PR-1, was induced by wounding and found to regulate immune responses against biological threats. As PR-1 is highly conserved across many organisms and the putative peptide from AtPR1 was also found to be bioactive in <I>Arabidopsis</I>, the results suggest that this peptide may be useful for enhancing resistance to stress in other plant species.</P><P>Many important cell-to-cell communication events in multicellular organisms are mediated by peptides, but only a few peptides have been identified in plants. In an attempt to address the difficulties in identifying plant signaling peptides, we developed a novel peptidomics approach and used this approach to discover defense signaling peptides in plants. In addition to the canonical peptide systemin, several novel peptides were confidently identified in tomato (<I>Solanum lycopersicum</I>) and quantified to be induced by both wounding and methyl jasmonate (MeJA). A wounding or wounding plus MeJA-induced peptide derived from the pathogenesis-related protein 1 (PR-1) family was found to induce significant antipathogen and minor antiherbivore responses in tomato. This study highlights a role for PR-1 in immune signaling and suggests the potential application of plant endogenous peptides in efforts to defeat biological threats in crop production. As PR-1 is highly conserved across many organisms and the putative peptide from At-PR1 was also found to be bioactive in <I>Arabidopsis thaliana</I>, our results suggest that this peptide may be useful for enhancing resistance to stress in other plant species.</P>