Browsing by Subject "Marker"

Now showing 1 - 2 of 2
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    Pilocytic astrocytoma: a review of genetic and molecular factors, diagnostic and prognostic markers
    (F. Hernández y Juan F. Madrid. Universidad de Murcia: Departamento de Biología Celular e Histología, 2014) Bikowska-Opalach, Barbara; Szlufik, Stanisław; Grajkowska, Wiesława; Jozwiak, Jaroslaw
    In spite of numerous studies concerning the pathogenesis of pilocytic astrocytoma (PA), the exact mechanism of the process still remains undetermined. It is difficult to obtain concordance between particular studies, which makes review of existing data especially troublesome. Nevertheless, the most important causative factors seem to be NF1 gene inactivation, in cases related to neurofibromatosis type 1, and BRAF gene overexpression in sporadic PAs, both resulting in MAPK/Erk pathway upregulation. Other molecular alterations, like mTOR or PI3K pathway deregulation, or Matrilin 2 overexpression, may influence the course of the disease, leading to the development of more aggressive and recurrent tumors. In the current paper we review genetic alterations in PA and describe currently studied molecular markers that may contribute to the development of the tumor and can be used in pathological staging of the malformation.
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    The visualization of oxidant stress in tissues and isolated cells
    (Francisco Hernández, Professor of Cell Biology, University of Murcia, Murcia, Spain, 2000) Frank, J.; Biesalsk, H. K.; Dominici, S.; Pompella, A.
    Many studies have implicated the role of oxidant stress in a wide range of human diseases and have led to the rapid expansion of research in this area. With many experimental approaches a direct detection of the production of reactive oxygen species (ROS) and free radicals is not possible. Free radicals are very reactive, short-lived and react in a non-specific way, so that ongoing oxidative damage is generally analyzed by measurement of secondary products e.g. H2O2, "oxidized" proteins, peroxidized lipids and their breakdown products, "oxidized" DNA or by fluorographic analysis in combination with fluorescent dyes e.g. dichlorofluorescin (DCFH). The histochemical visualization of selected molecular markers for oxidative phenomena can often provide valuable information concerning the distribution of oxidative processes in vivo. A number of biochemical methods are available for the monitoring of almost all oxidant stress-related processes, although their applicability in vivo is limited. This review summarizes the biochemical methods currently available for histochemical detection and indirect visualization of an excess of free radicals and ROS. The cited methods are discussed and the results obtained from their application are critically evaluated.