813 research outputs found

    Assessing Optic Neuritis in a Mouse Model of Multiple Sclerosis with Diffusion MR Imaging

    Get PDF
    Optic neuritis (ON) is an early manifestation in patients of multiple sclerosis (MS), typically resulting in visual dysfunction. The inflammatory demyelination of the optic nerve in ON closely resembles pathologies of the rest of central nervous system (CNS) white matter in MS. Since accumulated axonal degeneration in MS was considered as the potential cause leading to permanent disability, correlating optic nerve pathology and visual function in ON could be a model system to investigate the relationship between functional outcome and neuropathology. It may also present a new way to reflect the disease progression in MS. Various MR techniques have been used to assess inflammation (inflammatory cell infiltration and vasogenic edema) of ON, but rarely demonstrated the ability to image cellularity changes non-invasively. Diffusion MRI measures the Brownian motion of water molecules in the microstructure of biological tissues. Diffusion tensor imaging (DTI) holds the promise to provide a specific biomarker of axonal injury and demyelination in CNS white matter by axial diffusivity (the diffusion parallel to white matter fibers) and radial diffusivity (the diffusion perpendicular to white matter fibers), respectively. However, DTI assumes a single diffusion tensor model and thus takes an average of varied diffusion components. In contrast, our recently developed diffusion basis spectrum imaging (DBSI) resolves the complex diffusion components and provides relatively accurate directional diffusivities and diffusion component fractions, relating to the detail and accurate pathological picture of the disease or injury. In the current work, in vivo 25-direction DBSI was applied to the optic nerve of mice with experimental autoimmune encephalomyelitis (EAE), an animal model of MS, with visual impairment at onset of ON. Our results demonstrate that inflammation correlated well with visual impairment in acute ON. DBSI successfully detected inflammatory cell infiltration and optic nerve white matter pathology in EAE that was consistent with histology, supporting the capability of DBSI to quantify increased cellularity, axonal injury and myelin damage in the optic nerve of EAE mice

    An Analysis System for Integrating High-Throughput Transcript Abundance Data with Metabolic Pathways in Green Algae

    Get PDF
    As the most important non-vascular plants, algae have many research applications, including high species diversity, biofuel sources, adsorption of heavy metals and, following processing, health supplements. With the increasing availability of next-generation sequencing (NGS) data for algae genomes and transcriptomes, an integrated resource for retrieving gene expression data and metabolic pathway is essential for functional analysis and systems biology in algae. However, gene expression profiles and biological pathways are displayed separately in current resources, and making it impossible to search current databases directly to identify the cellular response mechanisms. Therefore, this work develops a novel AlgaePath database to retrieve gene expression profiles efficiently under various conditions in numerous metabolic pathways. AlgaePath, a web-based database, integrates gene information, biological pathways, and next-generation sequencing (NGS) datasets in Chlamydomonasreinhardtii and Neodesmus sp. UTEX 2219-4. Users can identify gene expression profiles and pathway information by using five query pages (i.e. Gene Search, Pathway Search, Differentially Expressed Genes (DEGs) Search, Gene Group Analysis, and Co-Expression Analysis). The gene expression data of 45 and 4 samples can be obtained directly on pathway maps in C. reinhardtii and Neodesmus sp. UTEX 2219-4, respectively. Genes that are differentially expressed between two conditions can be identified in Folds Search. Furthermore, the Gene Group Analysis of AlgaePath includes pathway enrichment analysis, and can easily compare the gene expression profiles of functionally related genes in a map. Finally, Co-Expression Analysis provides co-expressed transcripts of a target gene. The analysis results provide a valuable reference for designing further experiments and elucidating critical mechanisms from high-throughput data. More than an effective interface to clarify the transcript response mechanisms in different metabolic pathways under various conditions, AlgaePath is also a data mining system to identify critical mechanisms based on high-throughput sequencing

    Genetic copy number variants in sib pairs both affected with schizophrenia

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Schizophrenia is a complex disorder with involvement of multiple genes.</p> <p>Methods</p> <p>In this study, genome-wide screening for DNA copy-number variations (CNVs) was conducted for ten pairs, a total of 20 cases, of affected siblings using oligonucleotide array-based CGH.</p> <p>Results</p> <p>We found negative symptoms were significantly more severe (p < 0.05) in the subgroup that harbored more genetic imbalance (n ≧ 13, n = number of CNV-disrupted genes) as compared with the subgroup with fewer CNVs (n ≦ 6), indicating that the degree of genetic imbalance may influence the severity of the negative symptoms of schizophrenia. Four central nervous system (CNS) related genes including CCAAT/enhancer binding protein, delta (<it>CEBPD</it>, 8q11.21), retinoid × receptor, alpha (<it>RXRA</it>, 9q34.2), LIM homeobox protein 5 (<it>LHX5</it>, 12q24.13) and serine/threonine kinase 11 (<it>STK11</it>, 19p13.3) are recurrently (incidence ≧ 16.7%) disrupted by CNVs. Two genes, <it>PVR </it>(poliovirus receptor) and <it>BU678720</it>, are concordantly deleted in one and two, respectively, pairs of co-affected siblings. However, we did not find a significant association of this <it>BU678720 </it>deletion and schizophrenia in a large case-control sample.</p> <p>Conclusions</p> <p>We conclude that the high genetic loading of CNVs may be the underlying cause of negative symptoms of schizophrenia, and the CNS-related genes revealed by this study warrant further investigation.</p

    An Artificial Neural Network Embedded Position and Orientation Determination Algorithm for Low Cost MEMS INS/GPS Integrated Sensors

    Get PDF
    Digital mobile mapping, which integrates digital imaging with direct geo-referencing, has developed rapidly over the past fifteen years. Direct geo-referencing is the determination of the time-variable position and orientation parameters for a mobile digital imager. The most common technologies used for this purpose today are satellite positioning using Global Positioning System (GPS) and Inertial Navigation System (INS) using an Inertial Measurement Unit (IMU). They are usually integrated in such a way that the GPS receiver is the main position sensor, while the IMU is the main orientation sensor. The Kalman Filter (KF) is considered as the optimal estimation tool for real-time INS/GPS integrated kinematic position and orientation determination. An intelligent hybrid scheme consisting of an Artificial Neural Network (ANN) and KF has been proposed to overcome the limitations of KF and to improve the performance of the INS/GPS integrated system in previous studies. However, the accuracy requirements of general mobile mapping applications can’t be achieved easily, even by the use of the ANN-KF scheme. Therefore, this study proposes an intelligent position and orientation determination scheme that embeds ANN with conventional Rauch-Tung-Striebel (RTS) smoother to improve the overall accuracy of a MEMS INS/GPS integrated system in post-mission mode. By combining the Micro Electro Mechanical Systems (MEMS) INS/GPS integrated system and the intelligent ANN-RTS smoother scheme proposed in this study, a cheaper but still reasonably accurate position and orientation determination scheme can be anticipated

    Peripheral Sympathectomy for Raynaud's Phenomenon: A Salvage Procedure

    Get PDF
    We retrospectively reviewed the effectiveness of peripheral sympathectomy for severe Raynaud's phenomenon. In this study, a total of 14 digits from six patients with chronic digital ischemic change were included. All patients had pain, ulcer, or gangrenous change in the affected digits and were unresponsive to pharmacologic or other nonsurgical therapies. In all cases, angiography showed multifocal arterial lesions, so microvascular reconstruction was unfeasible. Peripheral sympathectomy was performed as a salvage procedure to prevent digit amputation. The results were analyzed according to reduction of pain, healing of ulcers, and prevention of amputation. In 12 of the 14 digits, the ulcers healed and amputation was avoided. In the other two digits, the ulcers improved and progressive gangrene was limited. As a salvage procedure for Raynaud's phenomenon recalcitrant to conservative treatment, peripheral sympathectomy improves perfusion to ischemic digits and enables amputation to be avoided

    NEUROPROTECTIVE EFFECT OF TERMINALIA CHEBULA EXTRACTS AND ELLAGIC ACID IN PC12 CELLS

    Get PDF
    Alzheimer’s disease (AD) is one of the most prevalent severe neurological disorders afflicting our aged population. The study was to determine neuroprotective effects of the Terminalia chebula extracts and ellagic acid by using beta-amyloid25-35 (Ab25-35)-induced cell cytotoxicity in undifferentiated rat pheochromocytoma (PC12) cellular model. The methanolic and water extracts of T. chebula and ellagic acid exhibited the strongest neuroprotective activity against Ab25-35-induced undifferentiated PC12 cell deaths at 0.5–5.0 ug/ml. The ellagic acid also exhibited the partial neuroprotective activity against H2O2-induced undifferentiated PC12 cell deaths at 0.5–5.0 ug/ml. The methanolic and water extracts of T. chebula and ellagic acid protected undifferentiated PC12 cells from the damaging effects of Ab25-35 in several ways: (1) by securing cell viability; (2) by suppressing reactive oxygen species production; and (3) by eliminating calcium ion influx. The T. chebula extracts maybe represent a promising plant-source for medicine in the application of the treatment of AD. Further investigation of the ellagic acid is necessary to verify the neuroprotective efficacy and mechanisms in vivo

    Label-free quantitative proteomics of CD133-positive liver cancer stem cells

    Full text link
    Abstract Background CD133-positive liver cancer stem cells, which are characterized by their resistance to conventional chemotherapy and their tumor initiation ability at limited dilutions, have been recognized as a critical target in liver cancer therapeutics. In the current work, we developed a label-free quantitative method to investigate the proteome of CD133-positive liver cancer stem cells for the purpose of identifying unique biomarkers that can be utilized for targeting liver cancer stem cells. Label-free quantitation was performed in combination with ID-based Elution time Alignment by Linear regression Quantitation (IDEAL-Q) and MaxQuant. Results Initially, IDEAL-Q analysis revealed that 151 proteins were differentially expressed in the CD133-positive hepatoma cells when compared with CD133-negative cells. We then analyzed these 151 differentially expressed proteins by MaxQuant software and identified 10 significantly up-regulated proteins. The results were further validated by RT-PCR, western blot, flow cytometry or immunofluorescent staining which revealed that prominin-1, annexin A1, annexin A3, transgelin, creatine kinase B, vimentin, and EpCAM were indeed highly expressed in the CD133-positive hepatoma cells. Conclusions These findings confirmed that mass spectrometry-based label-free quantitative proteomics can be used to gain insights into liver cancer stem cells.http://deepblue.lib.umich.edu/bitstream/2027.42/113089/1/12953_2012_Article_407.pd
    corecore