Search Results - (Author, Cooperation:A. Szekely)

2012-11-20

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Cell Differentiation ; Cells, Cultured ; Cellular Reprogramming ; Clone Cells ; DNA Copy Number Variations/*genetics ; Fibroblasts/cytology ; Gene Expression Profiling ; Genome, Human/genetics ; Humans ; Induced Pluripotent Stem Cells/cytology/*metabolism ; Male ; *Mosaicism ; Neurons/cytology ; Polymerase Chain Reaction ; Reproducibility of Results ; Skin/cytology/*metabolism

1471-4159

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Abstract: Polyamines positively modulate the activity of the N-methyl-d-aspartate (NMDA)-sensitive glutamate receptors. The concentration of polyamines in the brain increases in certain pathological conditions, such as ischemia and brain trauma, and these compounds have been postulated to play a role in excitotoxic neuronal death. In primary cultures of rat cerebellar granule neurons, exogenous application of the polyamines spermidine and spermine (but not putrescine) potentiated the delayed neurotoxicity elicited by NMDA receptor stimulation with glutamate. Furthermore, both toxic and nontoxic concentrations of glutamate stimulated the activity of ornithine decarboxylase (ODC)—the key regulatory enzyme in polyamine synthesis—and increased the concentration of ODC mRNA in cerebellar granule neurons but not in glial cells. Glutamate-induced ODC activation but not neurotoxicity was blocked by the ODC inhibitor difluoromethylornithine. Thus, high extracellular polyamine concentrations potentiate glutamate-triggered neuronal death, but the glutamate-induced increase in neuronal ODC activity may not play a determinant role in the cascade of intracellular events responsible for delayed excitotoxicity.

Electronic Resource

0021-9673

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

1432-1440

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1432-0568

Key words Radial glia ; Astrocyte development ; Tectum ; Ectostriatum ; Nucleus laminaris

Springer Online Journal Archives 1860-2000

Medicine

Abstract  The present study describes the distribution of glial fibrillary acidic protein (GFAP) and vimentin-immunopositive structures in the brain of the domestic chicken (Gallus domesticus) from hatching to maturity. The telencephalon is penetrated by a vimentin-immunopositive radial fibre system, representing a modified form of radial glia, in day-old chicks. Numerous fibres of this system persist until adulthood, mainly in the lobus parolfactorius, lamina medullaris dorsalis and lamina frontalis superior. GFAP immunoreactivity also appears in the course of development in these fibres. The distribution of GFAP-immunopositive astrocytes in the post-hatch telencephalon is like that found in adult chicken, except for the ectostriatum, in which an adult-like GFAP-immunostaining only develops during week three. This delay may be associated with a relatively slow maturation of this visual centre. In the diencephalon and in the mesencephalic tegmentum of day-old chicks GFAP-immunopositive astrocytes are confined to the border zone of several nuclei. In these areas as well as in the pons most GFAP positive astrocytes only appear gradually during the first two post-hatch weeks, although radial fibres occur only sparsely at hatch. Summarizing these results, a gradual replacement of radial fibres by astrocytes, typical of mammals, cannot be found in chicken. In the nucleus laminaris we observed a characteristic palisade of non-ependymal glia, reactive to GFAP but not to vimentin, which almost completely disappears by adulthood. We suggest that this glial system is instrumental in the development of the dendritic organisation of this nucleus. The optic tectum displays a dense array of GFAP-immunopositive radial glia at hatching, similar in this to the situation found in reptiles. However, in the tectum of reptiles this radial glia persists for the lifetime, whereas in the chick it disappears from the superficial tectal layers. This phenomenon may reflect the fact that there is no replacement of tectal cells or regeneration of retinotectal pathways in the chicken. In the early stage, the large cerebral tracts were found to contain dense accumulations of GFAP-positive cells, with peculiarly long outgrowths accompanying nerve fibres. No vimentin-immunopositivity was found in these glial elements; however vimentin was present in the glia situated at the optic chiasm, the anterior commissure and at other decussations. These structures, as well as the raphe, displayed the most intense vimentin-immunopositivity in the post-hatch chicken. This characteristic glial population may represent glial elements that have been reported to regulate fibre-crossing at the midline.

Electronic Resource

1432-8798

Springer Online Journal Archives 1860-2000

Medicine

Summary Distribution of antibodies to herpes simplex type 1 (HSV1), Epstein-Barr virus (EBV), cytomegalovirus (CMV) and measles virus (MV) was studied in sera and cerebrospinal fluids (CSF) of 41 patients with schizophrenia, 27 patients with primary affective disorders and 25 control patients with neurological diseases. No significant differences in distribution and mean geometric titers (GMT) of antibodies to HSV1 between the psychiatric and control groups were found. Distribution and GMT of antibodies to EBV were highly significant in psychiatric patients as compared to controls with highest titers in the affective disorder group. Antibodies to HSV1 were present in 15 CSF specimens of psychiatric patients with reduced CSF/serum ratio in 4, and low levels of antibodies were detected in 8 control patients. Antibodies to EBV-VCA were detected in 4 CSFs of psychiatric patients. Total protein levels were determined in CSF specimens and no correlation with antibodies was found. No significant differences in distribution of antibodies to CMV or MV in the three study groups were found. No antibodies to CMV were demonstrated in CSFs and in one specimen from a patient and two controls antibodies to MV were detected.

Electronic Resource

1435-4373

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource

1435-4373

Springer Online Journal Archives 1860-2000

Medicine

Electronic Resource