81 research outputs found
Politische Dimensionen von MilitĂ€rĂŒbungen und Manövern â ein Projektbericht
Die virtuellen Kriege und Operationen, die in MilitĂ€rĂŒbungen gespielt und geprobt werden, können entweder der Abschreckung dienen oder aber Angriffe vorbereiten bzw. zur Maskierung tatsĂ€chlicher Angriffe dienen. FĂŒr Beobachter ist es vielfach nicht offensichtlich, um welche Art von MilitĂ€rĂŒbung es sich handelt. Die Ergebnisse eines vierjĂ€hrigen internationalen Projektes zu politischen Dimensionen von MilitĂ€rĂŒbungen richten das Schlaglicht insbesondere auf MissverstĂ€ndnisse und deren ungewollte politische Auswirkungen, die im Extremfall unbeabsichtigt zum Krieg fĂŒhren können
Increased expression of receptor phosphotyrosine phosphatase-ÎČ/ζ is associated with molecular, cellular, behavioral and cognitive schizophrenia phenotypes
Schizophrenia is a serious and chronic mental disorder, in which both genetic and environmental factors have a role in the development of the disease. Neuregulin-1 (NRG1) is one of the most established genetic risk factors for schizophrenia, and disruption of NRG1 signaling has been reported in this disorder. We reported previously that NRG1/ErbB4 signaling is inhibited by receptor phosphotyrosine phosphatase-ÎČ/ζ (RPTP ÎČ/ζ) and that the gene encoding RPTPÎČ/ζ (PTPRZ1) is genetically associated with schizophrenia. In this study, we examined the expression of RPTPÎČ/ζ in the brains of patients with schizophrenia and observed increased expression of this gene. We developed mice overexpressing RPTPÎČ/ζ (PTPRZ1-transgenic mice), which showed reduced NRG1 signaling, and molecular and cellular changes implicated in the pathogenesis of schizophrenia, including altered glutamatergic, GABAergic and dopaminergic activity, as well as delayed oligodendrocyte development. Behavioral analyses also demonstrated schizophrenia-like changes in the PTPRZ1-transgenic mice, including reduced sensory motor gating, hyperactivity and working memory deficits. Our results indicate that enhanced RPTPÎČ/ζ signaling can contribute to schizophrenia phenotypes, and support both construct and face validity for PTPRZ1-transgenic mice as a model for multiple schizophrenia phenotypes. Furthermore, our results implicate RPTPÎČ/ζ as a therapeutic target in schizophrenia
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
Identification of Tmem10/opalin as an oligodendrocyte enriched gene using expression profiling combined with genetic cell ablation
Oligodendrocytes form an insulating multilamellar structure
of compact myelin around axons, which allows efficient
and rapid propagation of action potentials. However, little
is known about the molecular mechanisms operating at the
onset of myelination and during maintenance of the myelin
sheath in the adult. Here we use a genetic cell ablation
approach combined with Affymetrix GeneChip microarrays
to identify a number of oligodendrocyte-enriched genes that
may play a key role in myelination. One of the ââoligogenesââ
we cloned using this approach is Tmem10/Opalin, which
encodes for a novel transmembrane glycoprotein. In situ
hybridization and RT-PCR analysis revealed that Tmem10
is selectively expressed by oligodendrocytes and that its
expression is induced during their differentiation. Developmental
immunofluorescence analysis demonstrated that
Tmem10 starts to be expressed in the white matter tracks
of the cerebellum and the corpus callosum at the onset of
myelination after the appearance of other myelin genes
such as MBP. In contrast to the spinal cord and brain,
Tmem10 was not detected in myelinating Schwann cells,
indicating that it is a CNS-specific myelin protein. In
mature oligodendrocytes, Tmem10 was present at the cell
soma and processes, as well as along myelinated internodes,
where it was occasionally concentrated at the paranodes.
In myelinating spinal cord cultures, Tmem10 was
detected in MBP-positive cellular processes that were
aligned with underlying axons before myelination commenced.
These results suggest a possible role of Tmem10
in oligodendrocyte differentiation and CNS myelination.This work was supported by grants from the
Dr. Miriam and Sheldon G. Adelson Medical Research
Foundation
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