Entity

Time filter

Source Type

Wuppertal, Germany

Streibert P.F.,Witten/Herdecke University | Piroth W.,Helios Medical Center Wuppertal | Mansour M.,Helios Medical Center Wuppertal | Haage P.,Helios Medical Center Wuppertal | And 2 more authors.
Clinical Pediatrics | Year: 2011

The aim of this study was to evaluate the frequency of abnormal findings in magnetic resonance imaging (MRI) in children with headache, the clinical relevance of these findings, and whether more sophisticated technologies also result in more relevant abnormal findings. The MRIs of 1004 children with age ranging from 1 to 17 years were retrospectively analyzed. Children who were investigated with established sequences (n = 419) were compared with those examined with state-of-the-art MRI acquisition technology (n = 585). In 216/1004 investigations, MRI was performed because of headache (74/216 with established sequences, 142/216 with state-of-the-art acquisition technology). In 114/216 (52.8%) patients with headache, the MRI was abnormal with relevant findings in 23/114 patients and findings without clinical relevance in 91/114 children. A higher incidence of abnormal findings than in previous reports was found but there was only limited clinical gain of information using modern sequences in children with headache. © SAGE Publications 2011.


Hagedorn C.,Witten/Herdecke University | Baiker A.,Bayerisches Landesamt fur Gesundheit und Lebensmittelsicherheit | Postberg J.,Helios Medical Center Wuppertal | Ehrhardt A.,Witten/Herdecke University | Lipps H.J.,Witten/Herdecke University
Cold Spring Harbor Protocols | Year: 2012

The episomal status of S/MAR (scaffold/matrix attached region)-based vectors can be confirmed by several methods including Southern blots, fluorescence in situ hybridization (FISH) analysis, or plasmid rescue experiments. In rescue experiments, genomic DNA (gDNA) or DNA from Hirt extracts is isolated from cell clones or mixed populations in which S/MAR plasmids are stably established. Bacteria are transformed with this DNA and if episomal plasmid DNA (pDNA) is present, resistant bacterial colonies will form. © 2012 Cold Spring Harbor Laboratory Press.


Hagedorn C.,Witten/Herdecke University | Baiker A.,Bayerisches Landesamt fur Gesundheit und Lebensmittelsicherheit | Postberg J.,Helios Medical Center Wuppertal | Ehrhardt A.,Witten/Herdecke University | Lipps H.J.,Witten/Herdecke University
Cold Spring Harbor Protocols | Year: 2012

Nonviral episomal vectors represent attractive alternatives to currently used virus-based expression systems. In the late 1990s, it was shown that a plasmid containing an expression cassette linked to a scaffold/matrix attached region (S/MAR) replicates as a low copy number episome in all cell lines tested, as well as primary cells, and can be used for the genetic modification of higher animals. Once established in the cell, the S/MAR vector replicates early during S-phase and, in the absence of selection, is stably retained in the cells for an unlimited period of time. This vector can therefore be regarded as a minimal model system for studying the epigenetic regulation of replication and functional nuclear architecture. In theory, this construct represents an almost "ideal" expression system for gene therapy. In practice, S/MAR-based vectors stably modify mammalian cells with efficiencies far below those of virus-based constructs. Consequently, they have not yet found application in gene therapy trials. Furthermore, S/MAR vector systems are not trivial to handle and several critical technical issues have to be considered when modifying these vectors for various applications. © 2012 Cold Spring Harbor Laboratory Press.


Hagedorn C.,Witten/Herdecke University | Baiker A.,Bayerisches Landesamt fur Gesundheit und Lebensmittelsicherheit | Postberg J.,Helios Medical Center Wuppertal | Ehrhardt A.,Witten/Herdecke University | Lipps H.J.,Witten/Herdecke University
Cold Spring Harbor Protocols | Year: 2012

As with all eukaryotic replicons, the stable establishment of S/MAR (scaffold/matrix attached region) vectors is a stochastic event that depends on poorly understood epigenetic factors such as chromatin structure and nuclear localization. Establishment efficiency describes the percentage of cells in which a particular S/MAR vector is stably retained as an episome after an initial selection period. Expected establishment efficiency for S/MAR vectors is 1-5%. This article describes a colony-forming assay that may be used either to determine establishment efficiency or to generate single cell clones. © 2012 Cold Spring Harbor Laboratory Press.

Discover hidden collaborations