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Dive into the research topics where J. L. Frederiksen is active.

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Featured researches published by J. L. Frederiksen.


Journal of Clinical Investigation | 1999

Expression of specific chemokines and chemokine receptors in the central nervous system of multiple sclerosis patients

Torben Lykke Sørensen; Marie Tani; J. Jensen; Virginia Pierce; Claudia F. Lucchinetti; Virginia A Folcik; Shixin Qin; James B. Rottman; Finn Sellebjerg; Robert M. Strieter; J. L. Frederiksen; Richard M. Ransohoff

Chemokines direct tissue invasion by specific leukocyte populations. Thus, chemokines may play a role in multiple sclerosis (MS), an idiopathic disorder in which the central nervous system (CNS) inflammatory reaction is largely restricted to mononuclear phagocytes and T cells. We asked whether specific chemokines were expressed in the CNS during acute demyelinating events by analyzing cerebrospinal fluid (CSF), whose composition reflects the CNS extracellular space. During MS attacks, we found elevated CSF levels of three chemokines that act toward T cells and mononuclear phagocytes: interferon-gamma-inducible protein of 10 kDa (IP-10); monokine induced by interferon-gamma (Mig); and regulated on activation, normal T-cell expressed and secreted (RANTES). We then investigated whether specific chemokine receptors were expressed by infiltrating cells in demyelinating MS brain lesions and in CSF. CXCR3, an IP-10/Mig receptor, was expressed on lymphocytic cells in virtually every perivascular inflammatory infiltrate in active MS lesions. CCR5, a RANTES receptor, was detected on lymphocytic cells, macrophages, and microglia in actively demyelinating MS brain lesions. Compared with circulating T cells, CSF T cells were significantly enriched for cells expressing CXCR3 or CCR5. Our results imply pathogenic roles for specific chemokine-chemokine receptor interactions in MS and suggest new molecular targets for therapeutic intervention.


Journal of Neurology, Neurosurgery, and Psychiatry | 1994

Cerebrospinal fluid in the diagnosis of multiple sclerosis: a consensus report.

M. Andersson; José C. Álvarez-Cermeño; G. Bernardi; I. Cogato; Pam Fredman; J. L. Frederiksen; S. Fredrikson; P. Gallo; Lm. Grimaldi; M. Grønning; Geoffrey Keir; K. Lamers; Hans Link; A. Magalhaes; Ar. Massaro; Sten Öhman; Hansotto Reiber; L. Ronnback; M. Schluep; E. Schuller; Christian Sindic; Ej. Thompson; Maria Trojano; U. Wurster

The Committee of the European Concerted Action for Multiple Sclerosis (Charcot Foundation) organised five workshops to discuss CSF analytical standards in the diagnosis of multiple sclerosis. This consensus report from 12 European countries summarises the results of those workshops. It is hoped that neurologists will confer with their colleagues in clinical chemistry to arrange the best possible local practice. The most sensitive method for the detection of oligoclonal immunoglobulin bands is isoelectric focusing. The same amounts of IgG in parallel CSF and serum samples are used and oligoclonal bands are revealed with IgG specific antibody staining. All laboratories performing isoelectric focusing should check their technique at least annually using “blind” standards for the five different CSF and serum patterns. Quantitative measurements of IgG production in the CNS are less sensitive than isoelectric focusing. The preferred method for detection of blood-CSF barrier dysfunction is the albumin quotient. The CSF albumin or total protein concentrations are less satisfactory. These results must be interpreted with reference to the age of the patient and the local method of determination. Cells should be counted. The normal value is no more than 4 cells/microliters. Among evolving optional tests, measurement of the combined local synthesis of antibodies against measles, rubella, and/or varicella zoster could represent a significant advance if it offers higher specificity (not sensitivity) for identifying chronic rather than acute inflammation. Other tests that may have useful correlations with clinical indices include those for oligoclonal free light chains, IgM, IgA, or myelin basic protein concentrations.


Neurology | 2009

A consensus protocol for the standardization of cerebrospinal fluid collection and biobanking

Charlotte E. Teunissen; Axel Petzold; Jeffrey L. Bennett; Frode S. Berven; Lou Brundin; Manuel Comabella; Diego Franciotta; J. L. Frederiksen; Jo Fleming; Roberto Furlan; Rogier Q. Hintzen; Steve Hughes; Mh Johnson; E. Krasulova; Jens Kuhle; Maria-Chiara Magnone; Cecilia Rajda; Konrad Rejdak; Hk Schmidt; Vincent Van Pesch; Emmanuelle Waubant; Christian Wolf; Gavin Giovannoni; Bernhard Hemmer; Hayrettin Tumani; Florian Deisenhammer

There is a long history of research into body fluid biomarkers in neurodegenerative and neuroinflammatory diseases. However, only a few biomarkers in CSF are being used in clinical practice. One of the most critical factors in CSF biomarker research is the inadequate powering of studies because of the lack of sufficient samples that can be obtained in single-center studies. Therefore, collaboration between investigators is needed to establish large biobanks of well-defined samples. Standardized protocols for biobanking are a prerequisite to ensure that the statistical power gained by increasing the numbers of CSF samples is not compromised by preanalytical factors. Here, a consensus report on recommendations for CSF collection and biobanking is presented, formed by the BioMS-eu network for CSF biomarker research in multiple sclerosis. We focus on CSF collection procedures, preanalytical factors, and high-quality clinical and paraclinical information. The biobanking protocols are applicable for CSF biobanks for research targeting any neurologic disease.


Lancet Neurology | 2016

MRI criteria for the diagnosis of multiple sclerosis: MAGNIMS consensus guidelines

Massimo Filippi; Maria A. Rocca; O Ciccarelli; Nicola De Stefano; Nikos Evangelou; Ludwig Kappos; Alex Rovira; Jaume Sastre-Garriga; Mar Tintoré; J. L. Frederiksen; Claudio Gasperini; Jacqueline Palace; Daniel S. Reich; Brenda Banwell; Xavier Montalban; Frederik Barkhof

Summary In patients presenting with a clinically isolated syndrome (CIS), magnetic resonance imaging (MRI) can support and substitute clinical information for multiple sclerosis (MS) diagnosis demonstrating disease dissemination in space (DIS) and time (DIT) and helping to rule out other conditions that can mimic MS. From their inclusion in the diagnostic work-up for MS in 2001, several modifications of MRI diagnostic criteria have been proposed, in the attempt to simplify lesion-count models for demonstrating DIS, change the timing of MRI scanning for demonstrating DIT, and increase the value of spinal cord imaging. Since the last update of these criteria, new data regarding the application of MRI for demonstrating DIS and DIT have become available and improvement in MRI technology has occurred. State-of-the-art MRI findings in these patients were discussed in a MAGNIMS workshop, the goal of which was to provide an evidence-based and expert-opinion consensus on diagnostic MRI criteria modifications.


Neurology | 2010

MRI criteria for MS in patients with clinically isolated syndromes

Xavier Montalban; Mar Tintoré; Josephine Swanton; F. Barkhof; Franz Fazekas; Massimo Filippi; J. L. Frederiksen; Ludwig Kappos; Jacqueline Palace; Chris H. Polman; Marco Rovaris; N. De Stefano; Aj Thompson; Tarek A. Yousry; Alex Rovira; David H. Miller

In recent years, criteria for the diagnosis of multiple sclerosis (MS) have changed, mainly due to the incorporation of new MRI criteria. While the new criteria are a logical step forward, they are complex and—not surprisingly—a good working knowledge of them is not always evident among neurologists and neuroradiologists. In some circumstances, several MRI examinations are needed to achieve an accurate and prompt diagnosis. This provides an incentive for continued efforts to refine the incorporation of MRI-derived information into the diagnostic workup of patients presenting with a clinically isolated syndrome. Within the European multicenter collaborative research network that studies MRI in MS (MAGNIMS), a workshop was held in London in November 2007 to review information that may simplify the existing MS diagnostic criteria, while maintaining a high specificity that is essential to minimize false positive diagnoses. New data that are now published were reviewed and discussed and together with a new proposal are integrated in this position paper.


Magnetic Resonance Imaging | 1992

In vivo magnetic resonance diffusion measurement in the brain of patients with multiple sclerosis

Henrik Bo Wiberg Larsson; Carsten Thomsen; J. L. Frederiksen; Max Stubgaard; O. Henriksen

Measurement of water self-diffusion in the brain in 25 patients with multiple sclerosis was performed by magnetic resonance imaging. Quantitative diffusion measurements were obtained using single spin-echo pulse sequences with pulsed magnetic field gradients of different magnitude. Twenty-two of these patients also underwent measurement of the transverse relaxation time (T2). Only one plaque was evaluated in each patient. Based on prior knowledge, 12 plaques were classified as being 3 mo or less in age, and 7 plaques were classified as being more than 3 mo old. In all 25 plaques, water self-diffusion was found to be higher than in apparently normal white matter. Furthermore, water self-diffusion was found to be higher in acute plaques compared with chronic plaques. Finally, a slight tendency toward a relationship between the diffusion capability and T2 was found. We believe that an increased diffusion capability signifies an increase of the extracellular water space, which probably is related to the degree of demyelination. Thus, measurement of water self-diffusion in multiple sclerosis plaques may contribute to the study of pathogenesis of demyelination.


Neurology | 2009

Increased cerebrospinal fluid concentrations of the chemokine CXCL13 in active MS.

Finn Sellebjerg; Lars Börnsen; Mohsen Khademi; M. Krakauer; Tomas Olsson; J. L. Frederiksen; P. S. Sørensen

Background: Accumulating evidence supports a major role of B cells in multiple sclerosis (MS) pathogenesis. How B cells are recruited to the CNS is incompletely understood. Our objective was to study B-cell chemokine concentrations in MS, their relationship with disease activity, and how treatment with methylprednisolone and natalizumab affected the concentration in CSF. Methods: Using a cross-sectional design, CSF and blood samples were obtained from cohorts of patients with clinically isolated syndromes (CIS), relapsing-remitting MS (RRMS), primary progressive MS (PPMS), or secondary progressive MS (SPMS), and noninflammatory neurologic disease control subjects. Some patients with RRMS were studied before and after treatment with methylprednisolone or natalizumab. Results: In CSF, concentrations of CXCL13, but not CXCL12, were higher in patients with CIS, RRMS, SPMS, and PPMS than in controls. CSF concentrations of CXCL13 correlated with the CSF B-cell count, with markers of immune activation, and with disease activity in patients with CIS and RRMS. CSF concentrations of CXCL13 decreased after treatment with high-dose methylprednisolone and natalizumab. High CSF concentrations of CXCL13 correlated with low expression of messenger RNA encoding the immunoregulatory cytokines interleukin 10 and transforming growth factor β1, but not with the expression of T-helper type 1 (Th1) and Th17 factors. Conclusion: The chemokine CXCL13 may play a major role in recruitment of B cells and T-cell subsets expressing the chemokine receptor CXCR5 to the CNS in multiple sclerosis (MS), and may be a useful biomarker for treatment effects in MS. Furthermore, CXCL13 or its receptor CXCR5 should be considered as therapeutic targets in MS.


Lancet Neurology | 2006

MRI criteria for dissemination in space in patients with clinically isolated syndromes: a multicentre follow-up study

T Korteweg; Mar Tintoré; Bernard M. J. Uitdehaag; Alex Rovira; J. L. Frederiksen; David H. Miller; Kryshani Fernando; Massimo Filippi; Federica Agosta; Maria A. Rocca; Franz Fazekas; Christian Enzinger; Paul M. Matthews; Allyson Parry; Chris H. Polman; Xavier Montalban; Frederik Barkhof

BACKGROUND The McDonald International Panel accepted the Barkhof/Tintoré criteria for providing MRI evidence of dissemination in space to allow a diagnosis of multiple sclerosis in patients with clinically isolated syndromes (CIS). We applied these criteria in a large cohort of patients with CIS, representative of those seen in a general diagnostic setting, to assess their accuracy in predicting conversion to definite multiple sclerosis and to identify factors that affect this risk. METHODS In a collaborative study of seven centres, baseline MRI and clinical follow-up data for 532 patients with CIS were studied, with the development of a second clinical event used as the main outcome. All scans were scored for lesion counts and spatial lesion distribution to assess the fulfilment--ie, at least three out of four--of the Barkhof/Tintoré criteria. We used survival analysis and 2x2 tables to assess the test characteristics of the criteria at baseline. FINDINGS Overall conversion rate was 32.5% with a median survival time of 85.3 months. Fulfilment of the criteria at baseline showed, after a survival time of 2 years, a conversion rate of about 45% (95% CI 37-53) versus about 10% (6-16) in those with no asymptomatic lesions at baseline (p<0.0001). For patients with a follow-up of at least 2 years, the fulfilment of the MRI criteria showed an accuracy of 68% (sensitivity 49%, specificity 79%) for predicting conversion and an increase in risk of nearly four times for conversion compared with those not fulfilling the criteria (odds ratio 3.7, 95% CI 2.3-5.9; p<0.0001). Cox proportional hazards regression analysis accorded with this increased risk. No effects were recorded on the performance of the criteria by sex, presenting symptoms, or centre. Age at baseline did have a small but significant effect as predictor (hazard ratio 0.97, 0.95-0.99; p=0.002), but did not affect the prognostic value of the MRI criteria. INTERPRETATION MRI abnormalities have important prognostic value. The cut-off, based on the Barkhof/Tintoré criteria, as incorporated in the McDonald diagnostic scheme yields acceptable specificity, but could have lower sensitivity than previously reported.


Neurology | 1998

Double-blind, randomized, placebo-controlled study of oral, high-dose methylprednisolone in attacks of MS.

Finn Sellebjerg; J. L. Frederiksen; P. M. Nielsen; Jes Olesen

Objective: There is only limited evidence from adequately controlled clinical trials to support high-dose methylprednisolone therapy for attacks of multiple sclerosis (MS) and none supporting oral administration. We assessed the effect of oral high-dose methylprednisolone therapy in attacks of MS. Methods: Twenty-five patients with an attack of MS lasting less than 4 weeks were randomized to placebo treatment. Twenty-six patients received oral methylprednisolone (500 mg once a day for 5 days with a 10-day tapering period). The patients received scores on the Scripps Neurological Rating Scale (NRS) and Kurtzke Expanded Disability Status Scale. The symptoms were scored on a visual analog scale (VAS) before treatment and after 1, 3, and 8 weeks of treatment. Primary efficacy measures were NRS and VAS scores in the first 3 weeks and changes in NRS score and answers to an efficacy questionnaire administered after 8 weeks of treatment. Results: Changes in NRS scores among methylprednisolone- and placebo-treated patients differed significantly in the first 3 weeks and after 8 weeks(p = 0.005 and p = 0.0007). VAS scores the first 3 weeks and treatment efficacy after 8 weeks also favored a beneficial effect of methylprednisolone treatment (p = 0.02 and p = 0.05). After 1, 3, and 8 weeks, 4%, 24%, and 32% in the placebo group and 31%, 54%, and 65% in the methylprednisolone group had improved one point on the Expanded Disability Status Scale score (all p < 0.05). No serious adverse events were seen. Conclusion: Oral high-dose methylprednisolone is recommended for managing attacks of MS.


Neurology | 1999

A randomized, controlled trial of oral high-dose methylprednisolone in acute optic neuritis

Finn Sellebjerg; H. S. Nielsen; J. L. Frederiksen; Jes Olesen

Objective: To assess the efficacy of oral high-dose methylprednisolone in acute optic neuritis (ON). Background: It has been determined that oral high-dose methylprednisolone is efficacious in attacks of MS. Methods: A total of 60 patients with symptoms and signs of ON with a duration of less than 4 weeks and a visual acuity of 0.7 or less were randomized to treatment with placebo (n = 30) or oral methylprednisolone (n = 30; 500 mg daily for 5 days, with a 10-day tapering period). Visual function was measured and symptoms were scored on a visual analog scale (VAS) before treatment and after 1, 3, and 8 weeks. Primary efficacy measures were spatial vision and VAS scores the first 3 weeks (analysis of variance with baseline values as the covariate), and changes in spatial vision and VAS scores after 8 weeks. A significance level of p < 0.0125 was employed. Results: The VAS score (p = 0.008) but not the spatial visual function (p = 0.03) differed in methylprednisolone- and placebo-treated patients during the first 3 weeks. After 8 weeks the improvement in VAS scores (p = 0.8) and spatial visual function (p = 0.5) was comparable with methylprednisolone- and placebo-treated patients. A post hoc subgroup analysis suggested that patients with more severe baseline visual deficit and patients treated early after onset of symptoms had a more pronounced response to treatment. The risk of a new demyelinating attack within 1 year was unaffected by treatment. No serious adverse events were seen. Conclusion: Oral high-dose methylprednisolone treatment improves recovery from ON at 1 and 3 weeks, but no effect could be demonstrated at 8 weeks or on subsequent attack frequency.

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Massimo Filippi

Vita-Salute San Raffaele University

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Maria A. Rocca

Vita-Salute San Raffaele University

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Alex Rovira

Autonomous University of Barcelona

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Franz Fazekas

Medical University of Graz

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Mar Tintoré

Autonomous University of Barcelona

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Anna Tsakiri

University of Copenhagen

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Tjalf Ziemssen

Dresden University of Technology

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