0000000000954519

AUTHOR

Friedemann Paul

Power estimation for non-standardized multisite studies

A concern for researchers planning multisite studies is that scanner and T1-weighted sequence-related biases on regional volumes could overshadow true effects, especially for studies with a heterogeneous set of scanners and sequences. Current approaches attempt to harmonize data by standardizing hardware, pulse sequences, and protocols, or by calibrating across sites using phantom-based corrections to ensure the same raw image intensities. We propose to avoid harmonization and phantom-based correction entirely. We hypothesized that the bias of estimated regional volumes is scaled between sites due to the contrast and gradient distortion differences between scanners and sequences. Given this…

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Novel multiple sclerosis susceptibility loci implicated in epigenetic regulation

Genome-wide study in Germans identifies four novel multiple sclerosis risk genes and confirms already known gene loci.

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Bilateral vertebral artery dissection, agenesis of both ICAs, and connective tissue aberrations

A 35-year-old woman presented with acute signs of stroke (appendix e-1 on the Neurology® Web site at [www.neurology.org][1]). After initial CT with angiography, MRI with time-of-flight angiography confirmed agenesis of both internal carotid arteries (ICAs; figure 1A). It revealed bilateral vertebral artery (VA) dissections and ischemias in both middle artery territories (figure 1, A–E). Skin biopsy microscopy (figure 2) was consistent with ultrastructural connective tissue disease (uCTD), for which no further evidence was found apart from mild hypermobility of the finger joints. The underlying uCTD with structural instability of the arterial walls and the increased blood flow in the vertebr…

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MRI pattern recognition in multiple sclerosis normal-appearing brain areas

ObjectiveHere, we use pattern-classification to investigate diagnostic information for multiple sclerosis (MS; relapsing-remitting type) in lesioned areas, areas of normal-appearing grey matter (NAGM), and normal-appearing white matter (NAWM) as measured by standard MR techniques.MethodsA lesion mapping was carried out by an experienced neurologist for Turbo Inversion Recovery Magnitude (TIRM) images of individual subjects. Combining this mapping with templates from a neuroanatomic atlas, the TIRM images were segmented into three areas of homogenous tissue types (Lesions, NAGM, and NAWM) after spatial standardization. For each area, a linear Support Vector Machine algorithm was used in mult…

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Complete Epstein-Barr virus seropositivity in a large cohort of patients with early multiple sclerosis

ObjectiveTo determine the prevalence of antibodies to Epstein-Barr virus (EBV) in a large cohort of patients with early multiple sclerosis (MS).MethodsSerum samples were collected from 901 patients with a clinically isolated syndrome (CIS) or early relapsing–remitting multiple sclerosis (RRMS) participating in the German National MS cohort, a prospective cohort of patients with early MS with stringent inclusion criteria. Epstein-Barr nuclear antigen (EBNA)-1 and viral capsid antigen (VCA) antibodies were measured in diluted sera by chemiluminescence immunoassays (CLIAs). Sera of EBNA-1 and VCA antibody-negative patients were retested undiluted by an EBV IgG immunoblot. For comparison, we re…

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Clinical implications of serum neurofilament in newly diagnosed MS patients: a longitudinal multicentre cohort study

Abstract Background We aim to evaluate serum neurofilament light chain (sNfL), indicating neuroaxonal damage, as a biomarker at diagnosis in a large cohort of early multiple sclerosis (MS) patients. Methods In a multicentre prospective longitudinal observational cohort, patients with newly diagnosed relapsing-remitting MS (RRMS) or clinically isolated syndrome (CIS) were recruited between August 2010 and November 2015 in 22 centers. Clinical parameters, MRI, and sNfL levels (measured by single molecule array) were assessed at baseline and up to four-year follow-up. Findings Of 814 patients, 54.7% (445) were diagnosed with RRMS and 45.3% (369) with CIS when applying 2010 McDonald criteria (R…

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Fatigue in multiple sclerosis is closely related to sleep disorders: a polysomnographic cross-sectional study.

Background: Sleep disorders can cause tiredness. The relationship between sleep disorders and fatigue in patients with multiple sclerosis (MS) has not yet been investigated systematically. Objective: To investigate the relationship between fatigue and sleep disorders in patients with MS. Methods: Some 66 MS patients 20 to 66 years old were studied by overnight polysomnography. Using a cut-off point of 45 in the Modified Fatigue Impact Scale (MFIS), the entire cohort was stratified into a fatigued MS subgroup ( n = 26) and a non-fatigued MS subgroup ( n = 40). Results: Of the fatigued MS patients, 96% ( n = 25) were suffering from a relevant sleep disorder, along with 60% of the non-fatigue…

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Successful Replication of GWAS Hits for Multiple Sclerosis in 10,000 Germans Using the Exome Array

Genome-wide association studies (GWAS) successfully identified various chromosomal regions to be associated with multiple sclerosis (MS). The primary aim of this study was to replicate reported associations from GWAS using an exome array in a large German study. German MS cases (n = 4,476) and German controls (n = 5,714) were genotyped using the Illumina HumanExome v1-Chip. Genotype calling was performed with the Illumina Genome Studio(TM) Genotyping Module, followed by zCall. Single-nucleotide polymorphisms (SNPs) in seven regions outside the human leukocyte antigen (HLA) region showed genome-wide significant associations with MS (P values < 5 × 10(-8) ). These associations have been repor…

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Association of smoking but not HLA-DRB1*15:01, APOE or body mass index with brain atrophy in early multiple sclerosis

Background: The course of multiple sclerosis (MS) shows substantial inter-individual variability. The underlying determinants of disease severity likely involve genetic and environmental factors. Objective: The aim of this study was to assess the impact of APOE and HLA polymorphisms as well as smoking and body mass index (BMI) in the very early MS course. Methods: Untreated patients ( n = 263) with a recent diagnosis of relapsing-remitting (RR) MS or clinically isolated syndrome underwent standardized magnetic resonance imaging (MRI). Genotyping was performed for single-nucleotide polymorphisms (SNPs) rs3135388 tagging the HLA-DRB1*15:01 haplotype and rs7412 (Ɛ2) and rs429358 (Ɛ4) in APOE. …

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Treatment choices and neuropsychological symptoms of a large cohort of early MS

ObjectiveTo assess clinical characteristics, distribution of disease-modifying treatments (DMTs), and neuropsychological symptoms in a large cohort of patients with early-stage MS.MethodsThe German National MS Cohort is a multicenter prospective longitudinal cohort study that has recruited DMT-naive patients with clinically isolated syndrome (CIS) and relapsing-remitting MS (RRMS) since 2010. We evaluated their baseline characteristics and the prevalence of neuropsychological symptoms.ResultsOf 1,124 patients, with a 2.2:1 female-to-male ratio and median age at onset of 31.71 years (interquartile range [IQR]: 26.06–40.33), 44.6% and 55.3% had CIS and RRMS, respectively. The median Expanded …

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Low frequency and rare coding variation contributes to multiple sclerosis risk

AbstractMultiple sclerosis is a common, complex neurological disease, where almost 20% of risk heritability can be attributed to common genetic variants, including &gt;230 identified by genome-wide association studies (Patsopoulos et al., 2017). Multiple strands of evidence suggest that the majority of the remaining heritability is also due to the additive effects of individual variants, rather than epistatic interactions between these variants, or mutations exclusive to individual families. Here, we show in 68,379 cases and controls that as much as 5% of this heritability is explained by low-frequency variation in gene coding sequence. We identify four novel genes driving MS risk independe…

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MSJ763541_supplementary_material – Supplemental material for Association of smoking but not HLA-DRB1*15:01, APOE or body mass index with brain atrophy in early multiple sclerosis

Supplemental material, MSJ763541_supplementary_material for Association of smoking but not HLA-DRB1*15:01, APOE or body mass index with brain atrophy in early multiple sclerosis by Christiane Graetz, Adriane Gröge, Felix Luessi, Anke Salmen, Daniela Zöller, Janine Schultz, Nelly Siller, Vinzenz Fleischer, Barbara Bellenberg, Achim Berthele, Viola Biberacher, Joachim Havla, Michael Hecker, Reinhard Hohlfeld, Carmen Infante-Duarte, Jan S Kirschke, Tania Kümpfel, Ralf Linker, Friedemann Paul, Steffen Pfeuffer, Philipp Sämann, Gerrit Toenges, Frank Weber, Uwe K Zettl, Antje Jahn-Eimermacher, Gisela Antony, Sergiu Groppa, Heinz Wiendl, Bernhard Hemmer, Mark Mühlau, Carsten Lukas, Ralf Gold, Chri…

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Sunlight exposure exerts immunomodulatory effects to reduce multiple sclerosis severity

AbstractBackgroundMultiple sclerosis (MS) disease risk is associated with reduced sun exposure. This study assessed the relationship between measures of sun-exposure (vitamin D (vitD), latitude) and MS disease severity, the mechanisms of action, and effect-modification by medication and sun-sensitivity associated MC1R variants.MethodsTwo multi-center cohort studies (nNationMS=946, nBIONAT=991). Outcomes were the multiple sclerosis severity score (MSSS) and the number of Gd-enhancing lesion (GELs). RNAseq of four immune cell populations before and after UV-phototherapy of five MS patients.ResultsHigh serum vitD was associated with reduced MSSS (PNationMS=0.021; PBIONAT=0.007) and reduced ris…

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Is APOE ε4 associated with cognitive performance in early MS?

ObjectiveTo assess the impact of APOE polymorphisms on cognitive performance in patients newly diagnosed with clinically isolated syndrome (CIS) or relapsing-remitting MS (RRMS).MethodsThis multicenter cohort study included 552 untreated patients recently diagnosed with CIS or RRMS according to the 2005 revised McDonald criteria. The single nucleotide polymorphisms rs429358 (ε4) and rs7412 (ε2) of the APOE haplotype were assessed by allelic discrimination assays. Cognitive performance was evaluated using the 3-second paced auditory serial addition test and the Multiple Sclerosis Inventory Cognition (MUSIC). Sum scores were calculated to approximate the overall cognitive performance and memo…

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DeepWAS: Multivariate genotype-phenotype associations by directly integrating regulatory information using deep learning

Genome-wide association studies (GWAS) identify genetic variants associated with traits or diseases. GWAS never directly link variants to regulatory mechanisms. Instead, the functional annotation of variants is typically inferred by post hoc analyses. A specific class of deep learning-based methods allows for the prediction of regulatory effects per variant on several cell type-specific chromatin features. We here describe “DeepWAS”, a new approach that integrates these regulatory effect predictions of single variants into a multivariate GWAS setting. Thereby, single variants associated with a trait or disease are directly coupled to their impact on a chromatin feature in a cell type. Up to…

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