Johanna G Koster

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BACKGROUND AND PURPOSE Perinatal hypoxia-ischemia is a major cause of neonatal morbidity and mortality. Until now no established neuroprotective intervention after perinatal hypoxia-ischemia has been available. The delay in cell death after perinatal hypoxia-ischemia creates possibilities for therapeutic intervention after the initial insult. Excessive(More)
The Xwnt-5C gene is expressed in Xenopus embryos from the early gastrula stage onwards. The transcription of Xwnt-5C is regulated differentially with respect to transcript size, timing and localization. To gain insight into the generation of the Xwnt-5C expression pattern, we started to analyze the transcriptional regulation of this gene. We isolated(More)
Expression of the Engrailed-1 (XEn-1) gene was studied in Xenopus embryogenesis by Northern blot analysis and whole-mount in situ hybridization. One transcript of 2.2 kb was detected from stage 17 (midneurula) onwards, until stage 47 (swimming tadpole). The expression pattern of the XEn-1 gene as revealed by in situ hybridization can be divided in three(More)
Myositis is a rare manifestation of Lyme disease of unknown pathogenesis. This study describes the course of disease in eight patients with Lyme disease, aged 37-70 years, all of whom were suffering from histologically proven myositis. The clinical, electrophysiological, and myopathological findings are reported. One patient showed signs and symptoms of(More)
We have studied the spatial expression of the Xenopus GR in early embryos by whole-mount in situ hybridization. At the gastrula stage, GR mRNA is localized in the dorsal ectoderm. By the early neurula stage, GR transcripts were detected along the notoplate. Between mid and late neurula stages, GR mRNA was not detectable. At the tailbud stage, GR mRNA was(More)
High (pharmacological) doses of glucocorticoids inhibit the proliferation of growth plate chondrocytes, which leads to one of the side-effects of these steroids, namely suppression of longitudinal growth. Growth inhibition by glucocorticoids is thought to be mediated in part by impaired action of components of the IGF axis, which are important for(More)
Glucocorticoid (GC) treatment in childhood can lead to suppression of longitudinal growth as a side effect. The actions of GCs are thought to be mediated in part by impaired action of the insulin-like growth factors (IGF-I and IGF-II) and their binding proteins (IGFBP-1 to -6). We have studied the effects of GCs on IGF and IGFBP expression at the local(More)
In eukaryotes pre-tRNA species are processed at the 5' end by an endonuclease. Here we describe the first characterization of the structure of a eukaryotic pre-tRNA 5' processing endonuclease. The 5' pre-tRNAase, isolated from X. laevis ovaries, copurifies with a 16S macromolecular complex consisting of at least 14 polypeptides ranging in MW from about(More)
The insulin-like growth factors, IGF-I and IGF-II, and their binding proteins play an important role in the growth and development of the central nervous system. In the brain, colocalization of IGFs and IGFBPs often occurs, suggesting that IGFBPs can modulate IGF action. In one strain of our human (h)IGF-II transgenic mice, which carry an hIGF-II transgene(More)
We adapted the Biolistics Particle Delivery System for the introduction of DNA into Xenopus embryos, allowing us to modulate the expression of different genes at specific time points during development. In the present study we applied the Biolistics method to the study of the wnt-engrailed signaling cascade in the developing Xenopus embryo. We show that(More)