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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Anatomy and embryology 197 (1998), S. 369-376 
    ISSN: 1432-0568
    Keywords: Key words Glia ; Visual cortex ; Frontal cortex ; Brain organization and development ; Primate cerebral cortex
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Previous observations have shown that astrocytes with interlaminar processes are present in the cerebral cortex of humans and New and Old World monkeys, but not in the rodent. The present report furthers the analysis of possible evolutionary aspects regarding the expression of such astroglial features. A comparison between young and adult Microcebus murinus, a prosimian, and Old World monkeys (Macaca mulatta and Papio hamadryas) is presented. Brain samples were processed for glial fibrillary acidic protein (GFAP), vimentin, MAP2 and SMI 311 immunocytochemistry, using different procedures. The cerebral cortex of adult Microcebus showed the presence of long astroglial processes, albeit reduced in number and length with respect to those observed in Old World monkeys. Macaca and Papio showed dense packing of such processes extending in most cortical regions to a depth of approximately 700 micrometers. Based on double immunolabelling for GFAP and MAP 2 antigens, the location and extent of these processes was shown to overlap with areas traversed by bundles and individual apical dendrites. Aged Old World specimens depicted an increased thickness of terminal portions of interlaminar processes, with increased morphological alterations. Comparisons made between the average thickness of the ”brush” composed of interlaminar processes and the thickness of lamina I among the species analyzed disclosed an absence of relationship between them. This suggests that interlaminar processes do not represent cellular adaptations to the increase in thickness in superficial cortical laminae, but rather to some other evolutionary pressure. Since astroglial interlaminar processes are already present in a prosimian, although in a comparatively reduced manner, it is suggested that such processes underwent an early expression within the primate order, with increasing presence in more recent primate species.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Experimental brain research 63 (1986), S. 125-134 
    ISSN: 1432-1106
    Keywords: Parolfactory lobe ; Afferent connections ; Photogonadostimulation ; Fast blue ; Quail
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Unilateral injection of Fast Blue retrograde fluorescent neuron tracer into the parolfactory lobe (POL) in the quail showed multiple innervation of this structure. Neurons projecting into the POL were located in three areas: 1) the telencephalon, where they were scattered in the paleostriatum, the archistriatum and ventral hyperstriatum, and among the fibers of different tracts including the anterior commissure, the occipito-mesencephalic tract and the fasciculus prosencephali lateralis; 2) the diencephalon, where fluorescent neurons with large multipolar perikarya were found in the dorsal thalamic wall; 3) the midbrain, where large perikarya were located in the ventralis area of Tsai, the locus coeruleus, the nucleus subcoeruleus, around the medial longitudinal fasciculus, in the substantia grisea centralis, the formatio reticularis mesencephali and among the fibers of the brachium conjunctivum. In most cases, axons innervating the POL ran parallel to the fibers of the medial forebrain bundle and contralateral to the perikarya from which they originated. This study also showed that the anterior and posterior parts of the POL received fibres from different sources.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Peptides 9 (1988), S. 697-707 
    ISSN: 0196-9781
    Keywords: Brain ; Cerebrospinal fluid ; Corticotropin-releasing factor localization ; Immunocytochemistry ; Pigeon
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    General and Comparative Endocrinology 52 (1983), S. 56-66 
    ISSN: 0016-6480
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Biology , Medicine
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-0533
    Keywords: Key words Alzheimer’s disease ; Amyloid deposits ; Mouse lemur ; primates ; Tau protein
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Recent studies have revealed the presence of tau protein-immunoreactive accumulations and β amyloid protein (Aβ) deposits in the cerebral cortex of the aged mouse lemur, Microcebus murinus. To examine the age-related evolution of these changes and compare their regional distribution to that reported for humans and nonhuman primates with Alzheimer’s disease lesions, we performed a quantitative analysis of a large series of mouse lemurs aged from 1 to 13 years. The prevalence and density of tau protein-immunoreactive accumulations in the neocortex of this prosimian increased steadily with age. Neocortical areas were frequently affected even in young mouse lemurs, whereas the subiculum and entorhinal cortex were only involved occasionally in animals older than 8 years. As in anthropoid primates, diffuse Aβ deposits were often observed in the cerebral cortex and amygdala of old mouse lemurs. Although all animals with diffuse Aβ deposits had tau protein-immunoreactive accumulations in the neocortex, no correlation was found between the densities of these lesions in each area and among the areas studied. The age-dependent progression of tau protein-immunoreactive accumulations indicates that this prosimian may represent a valuable model for the study of the biochemical mechanisms of brain aging, while the relative sparing of hippocampus in mouse lemurs contrasts sharply with previous reports on neurofibrillary tangle formation in humans, and suggests that this animal may also be useful to investigate the biological characteristics of neuroprotection in this area. Furthermore, the present data indicate that Aβ deposition in mouse lemurs is not age dependent, but occurs in a few vulnerable old animals.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Cellular and molecular life sciences 32 (1976), S. 1443-1445 
    ISSN: 1420-9071
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Degenerating nervous fibres and synaptic boutons were demonstrated in the nuclei posterior medialis hypothalami after hippocampal lesions in the pigeon (light and electron microscopy).
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 188 (1978), S. 99-106 
    ISSN: 1432-0878
    Keywords: LHRH-neurosecretion ; Avian hypothalamus ; Vasotocin neurosecretion ; Immunocytochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary A fluorescent technique applying specific LHRH and vasotocin antisera was used for the immunocytochemical localization of the respective neurosecretory systems in the hypothalamus of gonadectomized, testosteronetreated and/or serotonin injected male domestic ducks. An immunoreactive (IR) LHRH-producing system, with perikarya located in the preoptic nucleus, could be traced through the ventral hypothalamus down to the external layer of the rostral and caudal ME, in close vicinity to the hypophysial portal system. An IR-vasotocin system originating in the paraventricular and supraoptic nuclei ran through the ventral hypothalamus, but terminated in (i) the external layer of the rostral ME, and (ii) in the posterior lobe of the hypophysis.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1432-0878
    Keywords: Acanthodactylus erythrurus (Lacertidae) ; Nuclear RNA ; Progressive elimination ; Mature spermatids
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Description / Table of Contents: Zusammenfassung Mit cytochemischen Untersuchungsmethoden haben wir bei der Eidechse Acanthodactylus erythrurus festgestellt, daß die Kern-RNS aus den älteren Spermatiden eliminiert wird. So wird die chromatingebundene-RNS, die während der gesamten Spermiogenese beobachtet werden kann, erst im letzten Stadium der Spermiogenese ausgestoßen, das heißt im Stadium der Umwandlung der Spermatiden in Spermien. Diese Ergebnisse stehen nicht im Einklang mit denen, die bei Insekten gewonnen wurden. Bei den letzteren verschwindet die RNS des Zellkerns und der Nukleolen in den Anfangsstadien der Spermiogenese.
    Abstract: Résumé Nous avons abservé au moyen de méthodes cytochimiques, l'élimination progressive de l'ARN nucléaire dans les spermatides âgées d'un Lézard. Il ressort de cette étude que l'ARN lié à la chromatine s'observe pendant toute la spermiogenèse et n'est éliminé qu'au terme ultime de cette spermiogenèse c'est à dire au moment de la transformation de la spermatide en spermatozoïde. Ces résultats diffèrent de ceux obtenus chez un Insecte où l'ARN nucléaire disparaît aux tous premiers stades de la spermiogenèse, en même temps que les nucléoles.
    Notes: Summary Cytochemical methods have shown a progressive elimination of nuclear RNA from mature spermatids in the lizard Acanthodactylus erythrurus. The RNA bound to chromatin has been observed throughout spermiogenesis and is eliminated only at the final stage, i. e., the stage of transformation from the spermatid to the spermatozoon. These results differ from those obtained in insects where the nuclear as well as the nucleolar RNA disappears during the early stages of spermiogenesis.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Cell & tissue research 168 (1976), S. 343-360 
    ISSN: 1432-0878
    Keywords: Retinohypothalamic connections ; Suprachiasmatic nucleus ; Optic chiasma ; Duck
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Retinohypothalamic connections were studied in the duck after unilateral optic nerve transection using both light and electron microscopic techniques. Degenerated endings of optic fibers were found only in a circumscribed part of the anterior hypothalamic area, i.e. the ventral region of the contralateral suprachiasmatic nucleus. Images of degenerating boutons were observed in frozen sections (method according to Johnstone-Bowsher), and their presence confirmed by electron microscopic examination. These degenerating boutons make synaptic contacts with dendrites or dendritic spines of neurons of the suprachiasmatic nucleus. In the same material, the decussation of the optic chiasma was studied with the light microscope. Uncrossed retinal fibers were found in the marginal optic tract, the basal optic root and occasionally also in the isthmo-optic tract.
    Type of Medium: Electronic Resource
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