59 research outputs found

    PEM Single Cells under Differential Conditions: Full Factorial Parameterization of the ORR and HOR Kinetics and Loss Analysis

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    The anode and cathode kinetics are parameterized based on differential cell measurements. Systematic parameter variations are evaluated to disentangle the dependencies of the electrochemical impedance spectroscopy (EIS) signatures in H2/H2 mode. We introduce a new CO recovery protocol for both electrodes that enables to accurately characterize the hydrogen oxidation reaction (HOR) kinetics. Then, we demonstrate that a compact Tafel kinetics law captures the oxygen reduction reaction (ORR) kinetics for a full factorial grid of conditions, covering a wide range of relative humidities (rH), temperatures, oxygen partial pressures and current densities. This yields the characteristic activation energy and effective reaction order, and we reconcile models that make different assumptions regarding the rH dependency. Moreover, we analyze O2 transport contributions by steady-state and transient limiting current techniques and heliox measurements. Although the rising uncertainty of loss corrections at high current densities makes it impossible to unambiguously identify an intrinsic potential-dependent change of the Tafel slope, our data support that such effect needs not be considered for steady-state cathodic half-cell potentials above 0.8

    Preparation of Metal-Containing Diamond-Like Carbon Films by Magnetron Sputtering and Plasma Source Ion Implantation and Their Properties

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    Metal-containing diamond-like carbon (Me-DLC) films were prepared by a combination of plasma source ion implantation (PSII) and reactive magnetron sputtering. Two metals were used that differ in their tendency to form carbide and possess a different sputter yield, that is, Cu with a relatively high sputter yield and Ti with a comparatively low one. The DLC film preparation was based on the hydrocarbon gas ethylene (C2H4). The preparation technique is described and the parameters influencing the metal content within the film are discussed. Film properties that are changed by the metal addition, such as structure, electrical resistivity, and friction coefficient, were evaluated and compared with those of pure DLC films as well as with literature values for Me-DLC films prepared with a different hydrocarbon gas or containing other metals

    Galectin-4 Controls Intestinal Inflammation by Selective Regulation of Peripheral and Mucosal T Cell Apoptosis and Cell Cycle

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    Galectin-4 is a carbohydrate-binding protein belonging to the galectin family. Here we provide novel evidence that galectin-4 is selectively expressed and secreted by intestinal epithelial cells and binds potently to activated peripheral and mucosal lamina propria T-cells at the CD3 epitope. The carbohydrate-dependent binding of galectin-4 at the CD3 epitope is fully functional and inhibited T cell activation, cycling and expansion. Galectin-4 induced apoptosis of activated peripheral and mucosal lamina propria T cells via calpain-, but not caspase-dependent, pathways. Providing further evidence for its important role in regulating T cell function, galectin-4 blockade by antisense oligonucleotides reduced TNF-alpha inhibitor induced T cell death. Furthermore, in T cells, galectin-4 reduced pro-inflammatory cytokine secretion including IL-17. In a model of experimental colitis, galectin-4 ameliorated mucosal inflammation, induced apoptosis of mucosal T-cells and decreased the secretion of pro-inflammatory cytokines. Our results show that galectin-4 plays a unique role in the intestine and assign a novel role of this protein in controlling intestinal inflammation by a selective induction of T cell apoptosis and cell cycle restriction. Conclusively, after defining its biological role, we propose Galectin-4 is a novel anti-inflammatory agent that could be therapeutically effective in diseases with a disturbed T cell expansion and apoptosis such as inflammatory bowel disease

    Optimising monitoring in the management of Crohn's disease: a physician's perspective.

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    Management of Crohn's disease has traditionally placed high value on subjective symptom assessment; however, it is increasingly appreciated that patient symptoms and objective parameters of inflammation can be disconnected. Therefore, strategies that objectively monitor inflammatory activity should be utilised throughout the disease course to optimise patient management. Initially, a thorough assessment of the severity, location and extent of disease is needed to ensure a correct diagnosis, identify any complications, help assess prognosis and select appropriate therapy. During follow-up, clinical decision-making should be driven by disease activity monitoring, with the aim of optimising treatment for tight disease control. However, few data exist to guide the choice of monitoring tools and the frequency of their use. Furthermore, adaption of monitoring strategies for symptomatic, asymptomatic and post-operative patients has not been well defined. The Annual excHangE on the ADvances in Inflammatory Bowel Disease (IBD Ahead) 2011 educational programme, which included approximately 600 gastroenterologists from 36 countries, has developed practice recommendations for the optimal monitoring of Crohn's disease based on evidence and/or expert opinion. These recommendations address the need to incorporate different modalities of disease assessment (symptom and endoscopic assessment, measurement of biomarkers of inflammatory activity and cross-sectional imaging) into robust monitoring. Furthermore, the importance of measuring and recording parameters in a standardised fashion to enable longitudinal evaluation of disease activity is highlighted.Peer reviewe

    The Human Phenotype Ontology in 2024: phenotypes around the world.

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    The Human Phenotype Ontology (HPO) is a widely used resource that comprehensively organizes and defines the phenotypic features of human disease, enabling computational inference and supporting genomic and phenotypic analyses through semantic similarity and machine learning algorithms. The HPO has widespread applications in clinical diagnostics and translational research, including genomic diagnostics, gene-disease discovery, and cohort analytics. In recent years, groups around the world have developed translations of the HPO from English to other languages, and the HPO browser has been internationalized, allowing users to view HPO term labels and in many cases synonyms and definitions in ten languages in addition to English. Since our last report, a total of 2239 new HPO terms and 49235 new HPO annotations were developed, many in collaboration with external groups in the fields of psychiatry, arthrogryposis, immunology and cardiology. The Medical Action Ontology (MAxO) is a new effort to model treatments and other measures taken for clinical management. Finally, the HPO consortium is contributing to efforts to integrate the HPO and the GA4GH Phenopacket Schema into electronic health records (EHRs) with the goal of more standardized and computable integration of rare disease data in EHRs

    Increased serum miR-193a-5p during non-alcoholic fatty liver disease progression: diagnostic and mechanistic relevance

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    Background & Aims: Serum microRNAs (miRNAs) levels are known to change in non-alcoholic fatty liver disease (NAFLD) and may serve as useful biomarkers. This study aimed to profile miRNAs comprehensively at all NAFLD stages.Methods: We profiled 2,083 serum miRNAs in a discovery cohort (183 NAFLD cases representing the complete NAFLD spectrum and 10 population controls). MiRNA libraries generated by HTG EdgeSeq were sequenced by Illumina NextSeq. Selected serum miRNAs were profiled in 372 additional NAFLD cases and 15 population controls by quantitative reverse transcriptase-polymerase chain reaction.Results: Levels of 275 miRNAs differed between cases and population controls. Fewer differences were seen within individual NAFLD stages but miR-193a-5p consistently the showed increased levels in all comparisons. Relative to NAFL/NASH with mild fibrosis (stage 0/1), three miRNAs (miR-193a-5p, miR-378d and miR378d) were increased in cases with NASH and clinically significant fibrosis (stage 2-4), seven (miR193a-5p, miR-378d, miR-378e, miR-320b, c, d & e) increased in cases with NAFLD Activity Score (NAS) 5-8 compared with lower NAS, and three (miR-193a-5p, miR-378d, miR-378e) increased but one (miR-19b-3p) decreased in steatosis, activity, and fibrosis "activity" (SAF-A) score 2-4 compared with lower SAF-A. The significant findings for miR-193a-5p were replicated in the additional NAFLD cohort. Studies in Hep G2 cells showed that following palmitic acid treatment, miR-193a-5p expression decreased significantly. Gene targets for miR-193a-5p were investigated in liver RNAseq data for a case subgroup (n=80); liver GPX8 levels correlated positively with serum miR-193a-5p. Conclusions: Serum miR-193a-5p levels correlate strongly with NAFLD activity grade and fibrosis stage. MiR-193a-5p may have a role in the hepatic response to oxidative stress and is a potential clinically tractable circulating biomarker for progressive NAFLD

    Solve-RD: systematic pan-European data sharing and collaborative analysis to solve rare diseases.

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    For the first time in Europe hundreds of rare disease (RD) experts team up to actively share and jointly analyse existing patient's data. Solve-RD is a Horizon 2020-supported EU flagship project bringing together >300 clinicians, scientists, and patient representatives of 51 sites from 15 countries. Solve-RD is built upon a core group of four European Reference Networks (ERNs; ERN-ITHACA, ERN-RND, ERN-Euro NMD, ERN-GENTURIS) which annually see more than 270,000 RD patients with respective pathologies. The main ambition is to solve unsolved rare diseases for which a molecular cause is not yet known. This is achieved through an innovative clinical research environment that introduces novel ways to organise expertise and data. Two major approaches are being pursued (i) massive data re-analysis of >19,000 unsolved rare disease patients and (ii) novel combined -omics approaches. The minimum requirement to be eligible for the analysis activities is an inconclusive exome that can be shared with controlled access. The first preliminary data re-analysis has already diagnosed 255 cases form 8393 exomes/genome datasets. This unprecedented degree of collaboration focused on sharing of data and expertise shall identify many new disease genes and enable diagnosis of many so far undiagnosed patients from all over Europe

    Twist exome capture allows for lower average sequence coverage in clinical exome sequencing

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    Background Exome and genome sequencing are the predominant techniques in the diagnosis and research of genetic disorders. Sufficient, uniform and reproducible/consistent sequence coverage is a main determinant for the sensitivity to detect single-nucleotide (SNVs) and copy number variants (CNVs). Here we compared the ability to obtain comprehensive exome coverage for recent exome capture kits and genome sequencing techniques. Results We compared three different widely used enrichment kits (Agilent SureSelect Human All Exon V5, Agilent SureSelect Human All Exon V7 and Twist Bioscience) as well as short-read and long-read WGS. We show that the Twist exome capture significantly improves complete coverage and coverage uniformity across coding regions compared to other exome capture kits. Twist performance is comparable to that of both short- and long-read whole genome sequencing. Additionally, we show that even at a reduced average coverage of 70× there is only minimal loss in sensitivity for SNV and CNV detection. Conclusion We conclude that exome sequencing with Twist represents a significant improvement and could be performed at lower sequence coverage compared to other exome capture techniques

    Solving patients with rare diseases through programmatic reanalysis of genome-phenome data.

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    Funder: EC | EC Seventh Framework Programm | FP7 Health (FP7-HEALTH - Specific Programme "Cooperation": Health); doi: https://doi.org/10.13039/100011272; Grant(s): 305444, 305444Funder: Ministerio de Economía y Competitividad (Ministry of Economy and Competitiveness); doi: https://doi.org/10.13039/501100003329Funder: Generalitat de Catalunya (Government of Catalonia); doi: https://doi.org/10.13039/501100002809Funder: EC | European Regional Development Fund (Europski Fond za Regionalni Razvoj); doi: https://doi.org/10.13039/501100008530Funder: Instituto Nacional de Bioinformática ELIXIR Implementation Studies Centro de Excelencia Severo OchoaFunder: EC | EC Seventh Framework Programm | FP7 Health (FP7-HEALTH - Specific Programme "Cooperation": Health)Reanalysis of inconclusive exome/genome sequencing data increases the diagnosis yield of patients with rare diseases. However, the cost and efforts required for reanalysis prevent its routine implementation in research and clinical environments. The Solve-RD project aims to reveal the molecular causes underlying undiagnosed rare diseases. One of the goals is to implement innovative approaches to reanalyse the exomes and genomes from thousands of well-studied undiagnosed cases. The raw genomic data is submitted to Solve-RD through the RD-Connect Genome-Phenome Analysis Platform (GPAP) together with standardised phenotypic and pedigree data. We have developed a programmatic workflow to reanalyse genome-phenome data. It uses the RD-Connect GPAP's Application Programming Interface (API) and relies on the big-data technologies upon which the system is built. We have applied the workflow to prioritise rare known pathogenic variants from 4411 undiagnosed cases. The queries returned an average of 1.45 variants per case, which first were evaluated in bulk by a panel of disease experts and afterwards specifically by the submitter of each case. A total of 120 index cases (21.2% of prioritised cases, 2.7% of all exome/genome-negative samples) have already been solved, with others being under investigation. The implementation of solutions as the one described here provide the technical framework to enable periodic case-level data re-evaluation in clinical settings, as recommended by the American College of Medical Genetics
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