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Dive into the research topics where Siw Johannesen is active.

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Featured researches published by Siw Johannesen.


Cytokine | 2014

Safety and feasibility of long term administration of recombinant human granulocyte-colony stimulating factor in patients with amyotrophic lateral sclerosis.

Jochen Grassinger; Andrei Khomenko; Christina Hart; Dobri Baldaranov; Siw Johannesen; Gunnar Mueller; Roland Christian Schelker; Wilhelm Schulte-Mattler; Reinhard Andreesen; Ulrich Bogdahn

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive neuronal disease resulting in a loss of the upper and lower motor neurons and subsequent death within three to four years after diagnosis. Mouse models and preliminary human exposure data suggest that the treatment with granulocyte-colony stimulating factor (G-CSF) has neuro-protective effects and may delay ALS progression. As data on long-term administration of G-CSF in patients with normal bone marrow (BM) function are scarce, we initiated a compassionate use program including 6 ALS patients with monthly G-CSF treatment cycles. Here we demonstrate that G-CSF injection was safe and feasible throughout our observation period up to three years. Significant decrease of mobilization efficiency occurred in one patient and a loss of immature erythroid progenitors was observed in all six patients. These data imply that follow-up studies analyzing BM function during long-term G-CSF stimulation are required.


Lancet Neurology | 2018

Safety and efficacy of rasagiline as an add-on therapy to riluzole in patients with amyotrophic lateral sclerosis: a randomised, double-blind, parallel-group, placebo-controlled, phase 2 trial

Albert C. Ludolph; Joachim Schuster; Johannes Dorst; Luc Dupuis; Jens Dreyhaupt; Jochen H. Weishaupt; Jan Kassubek; Ulrike Weiland; Susanne Petri; Thomas Meyer; Julian Grosskreutz; Berthold Schrank; Matthias Boentert; Alexander Emmer; Andreas Hermann; Daniel Zeller; Johannes Prudlo; Andrea Sylvia Winkler; Torsten Grehl; Michael T. Heneka; Siw Johannesen; Bettina Göricke; Andreas Funke; Dagmar Kettemann; Robert Meyer; Kai Gruhn; Peter Schwenkreis; Philipp Stude; MichaelT Heneka; Delia Kurzwelly

BACKGROUND Rasagiline, a monoamine oxidase B inhibitor with neuroprotective potential in Parkinsons disease, has shown a disease-modifying effect in the SOD1-Gly93Ala low-expressing mouse model of amyotrophic lateral sclerosis, both alone and in combination with riluzole. We sought to test whether or not rasagiline 1 mg/day can prolong survival in patients with amyotrophic lateral sclerosis also receiving riluzole. METHODS Patients with possible, probable, or definite amyotrophic lateral sclerosis were enrolled to our randomised, placebo-controlled, parallel-group, double-blind, phase 2 trial from 15 German network for motor neuron diseases (MND-NET) centres (university hospitals or clinics). Eligible patients were aged at least 18 years, had onset of progressive weakness within the 36 months before the study, had disease duration of more than 6 months and less than 3 years, and had a best-sitting slow vital capacity of at least 50%. After a 4-week screening period, eligible patients were randomly assigned (1:1) to receive either rasagiline (1 mg/day) or placebo in addition to riluzole (100 mg/day), after stratification for site of onset (bulbar or spinal) and study centre. Patients and all personnel assessing outcome parameters were masked to treatment allocation. Patients were followed up 2, 6, 12, and 18 months after randomisation. The primary endpoint was survival time, defined as the time to death or time to study cutoff date (ie, the last patients last visit plus 14 days). Analyses of primary outcome and safety measures were done in all patients who received at least one dose of trial treatment (intention-to-treat population). The trial is registered with ClinicalTrials.gov, number NCT01879241. FINDINGS Between July 2, 2013, and Nov 11, 2014, 273 patients were screened for eligibility, and 252 patients were randomly assigned to receive rasagiline (n=127) or placebo (n=125). 126 patients taking rasagiline and 125 taking placebo were included in the intention-to-treat analysis. For the primary outcome, the survival probability at the end of the study was 0·43 (95% CI 0·25-0·59) in the rasagiline group (n=126) and 0·53 (0·43-0·62) in the placebo group (n=125). The estimated effect size (hazard ratio) was 0·91 (one-sided 97·5% CI -infinity to 1·34; p=0·31). Rasagiline was well tolerated, and most adverse events were due to amyotrophic lateral sclerosis disease progression rather than treatment; the most frequent of these were dysphagia (32 [25%] taking rasagiline vs 24 [19%] taking placebo) and respiratory failure (25 [20%] vs 31 [25%]). Frequency of adverse events were comparable between both groups. INTERPRETATION Rasagiline was safe in patients with amyotrophic lateral sclerosis. There was no difference between groups in the primary outcome of survival, although post-hoc analysis suggested that rasagiline might modify disease progression in patients with an initial slope of Amyotrophic Lateral Sclerosis Functional Rating Scale Revised greater than 0·5 points per month at baseline. This should be confirmed in another clinical trial. FUNDING Teva Pharmaceutical Industries.


Frontiers in Neurology | 2017

The TGF-β System As a Potential Pathogenic Player in Disease Modulation of Amyotrophic Lateral Sclerosis

Sebastian Peters; Eva Zitzelsperger; Sabrina Kuespert; Sabine Iberl; Rosmarie Heydn; Siw Johannesen; Susanne Petri; Ludwig Aigner; Dietmar R. Thal; Andreas Hermann; Jochen H. Weishaupt; Tim-Henrik Bruun; Ulrich Bogdahn

Amyotrophic lateral sclerosis (ALS) represents a fatal orphan disease with high unmet medical need, and a life time risk of approx. 1/400 persons per population. Based on increasing knowledge on pathophysiology including genetic and molecular changes, epigenetics, and immune dysfunction, inflammatory as well as fibrotic processes may contribute to the heterogeneity and dynamics of ALS. Animal and human studies indicate dysregulations of the TGF-β system as a common feature of neurodegenerative disorders in general and ALS in particular. The TGF-β system is involved in different essential developmental and physiological processes and regulates immunity and fibrosis, both affecting neurogenesis and neurodegeneration. Therefore, it has emerged as a potential therapeutic target for ALS: a persistent altered TGF-β system might promote disease progression by inducing an imbalance of neurogenesis and neurodegeneration. The current study assessed the activation state of the TGF-β system within the periphery/in life disease stage (serum samples) and a late stage of disease (central nervous system tissue samples), and a potential influence upon neuronal stem cell (NSC) activity, immune activation, and fibrosis. An upregulated TGF-β system was suggested with significantly increased TGF-β1 protein serum levels, enhanced TGF-β2 mRNA and protein levels, and a strong trend toward an increased TGF-β1 protein expression within the spinal cord (SC). Stem cell activity appeared diminished, reflected by reduced mRNA expression of NSC markers Musashi-1 and Nestin within SC—paralleled by enhanced protein contents of Musashi-1. Doublecortin mRNA and protein expression was reduced, suggesting an arrested neurogenesis at late stage ALS. Chemokine/cytokine analyses suggest a shift from a neuroprotective toward a more neurotoxic immune response: anti-inflammatory chemokines/cytokines were unchanged or reduced, expression of proinflammatory chemokines/cytokines were enhanced in ALS sera and SC postmortem tissue. Finally, we observed upregulated mRNA and protein expression for fibronectin in motor cortex of ALS patients which might suggest increased fibrotic changes. These data suggest that there is an upregulated TGF-β system in specific tissues in ALS that might lead to a “neurotoxic” immune response, promoting disease progression and neurodegeneration. The TGF-β system therefore may represent a promising target in treatment of ALS patients.


Frontiers in Neurology | 2018

Combinatory Biomarker Use of Cortical Thickness, MUNIX, and ALSFRS-R at Baseline and in Longitudinal Courses of Individual Patients With Amyotrophic Lateral Sclerosis

Anna Maria Wirth; Andrei Khomenko; Dobri Baldaranov; Ines Kobor; Ohnmar Hsam; Thomas Grimm; Siw Johannesen; Tim-Henrik Bruun; Wilhelm Schulte-Mattler; Mark W. Greenlee; Ulrich Bogdahn

Objective: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative process affecting upper and lower motor neurons as well as non-motor systems. In this study, precentral and postcentral cortical thinning detected by structural magnetic resonance imaging (MRI) were combined with clinical (ALS-specific functional rating scale revised, ALSFRS-R) and neurophysiological (motor unit number index, MUNIX) biomarkers in both cross-sectional and longitudinal analyses. Methods: The unicenter sample included 20 limb-onset classical ALS patients compared to 30 age-related healthy controls. ALS patients were treated with standard Riluzole and additional long-term G-CSF (Filgrastim) on a named patient basis after written informed consent. Combinatory biomarker use included cortical thickness of atlas-based dorsal and ventral subdivisions of the precentral and postcentral cortex, ALSFRS-R, and MUNIX for the musculus abductor digiti minimi (ADM) bilaterally. Individual cross-sectional analysis investigated individual cortical thinning in ALS patients compared to age-related healthy controls in the context of state of disease at initial MRI scan. Beyond correlation analysis of biomarkers at cross-sectional group level (n = 20), longitudinal monitoring in a subset of slow progressive ALS patients (n = 4) explored within-subject temporal dynamics of repeatedly assessed biomarkers in time courses over at least 18 months. Results: Cross-sectional analysis demonstrated individually variable states of cortical thinning, which was most pronounced in the ventral section of the precentral cortex. Correlations of ALSFRS-R with cortical thickness and MUNIX were detected. Individual longitudinal biomarker monitoring in four slow progressive ALS patients revealed evident differences in individual disease courses and temporal dynamics of the biomarkers. Conclusion: A combinatory use of structural MRI, neurophysiological and clinical biomarkers allows for an appropriate and detailed assessment of clinical state and course of disease of ALS.


Journal of the Neurological Sciences | 2013

Assessing motor units with an improved MUNIX

Ines Kobor; F. Stein; Andrei Khomenko; Dobri Baldaranov; Siw Johannesen; Tim-Henrik Bruun; Ulrich Bogdahn; Wilhelm Schulte-Mattler

In contrast to the original MUNIX method, with I-MUNIX a continuous SIP was recorded during increasing muscle contraction (Figure 1A). These recordings were subject to later analysis with the modified I-MUNIX-algorithms. The modifications included baseline correction, filter settings, rectification, SIP interval. For abductor digiti minimi (ADM) muscles 160 different parameter settings were applied, and 96 for trapezius (TRA) muscles. Thus, a total of 6080 I-MUNIX values were analyzed for ADM, and 2976 for TRA. To compensate artifacts in SIPs, a new parameter was introduced, maxArtarea, restricting the program to SIP intervals that did not differ from baseline above the maxArtarea value. For comparison, the results of I-MUNIX and the original MUNIX were each correlated to the results of the ‘gold-standard’ motor unit number estimation (MUNE) methods, respectively (Figure 2). For inter-rater agreement analysis, each muscle was studied by three independent persons (a clinical neurophysiologist, a specifically trained student, and a technician). The analyses of these data sets were run by another three independent raters, who were only briefly introduced into the I-MUNIX analysis. ASSESSING MOTOR UNITS WITH IMPROVED MUNIX


Neurology | 2015

Safety and Feasibility of G-CSF Compassionate use in ALS Patients (P6.009)

Andrei Khomenko; Dobri Baldaranov; Siw Johannesen; Ines Kobor; Josefine Blume; Tim-Henrik Bruun; Jochen Grassinger; Tina Kammermaier; Albert C. Ludolph; Michael Deppe; Gerhard Schuierer; Wilhelm Schulte-Mattler; Tim Friede; Rico Laage; Armin Schneider; Ulrich Bogdahn


Neurology | 2017

Approach towards an ALS-specific structural marker of motor tract integrity for the description of different ALS progression types using diffusion-weighted imaging (S53.003)

Anna Maria Wirth; Andrei Khomenko; Dobri Baldaranov; Siw Johannesen; Ines Kobor; Tim-Henrik Bruun; Mark W. Greenlee; Michael Deppe; Ulrich Bogdahn


Neurology | 2017

Specific human antisense oligonucleotide (ASO) targeting TGF-βRII rescues proliferation of TGF-β arrested human neuronal progenitor cells (ReNcell CX) (S5.007)

Sabrina Kuespert; Tim-Henrik Bruun; Eva Zitzelsperger; Rosmarie Heydn; Sebastian Peters; Siw Johannesen; Ludwig Aigner; Ulrich Bogdahn


Neurology | 2016

Biomarkers Reflect ALS Clinical Courses (P5.039)

Siw Johannesen; Dobri Baldaranov; Andrei Khomenko; Thomas Grimm; Ines Kobor; Tina Kammermaier; Jochen Grassinger; Sabine Klatt; Jan Kassubek; Michael Deppe; Gerhard Schuirer; Albert C. Ludolph; Wilhelm Schulte-Mattler; Isabeau Prémont-Schwarz; Armin Schneider; Tim-Henrik Bruun; Ulrich Bogdahn


Neurology | 2016

Immortalized Human Neuronal Progenitor Cells (ReNcell CX) Represent an Ideal Model to Investigate the Inhibition of Adult Neurogenesis in the SVZ Mediated by TGF-β (P5.095)

Sabrina Kuespert; Eva Zitzelsperger; Sebastian Peters; Siw Johannesen; Sabine Klatt; Tim-Henrik Bruun; Jochen Grassinger; Ludwig Aigner; Ulrich Bogdahn

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Ulrich Bogdahn

University of Regensburg

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Ines Kobor

University of Regensburg

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