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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 7 (1971), S. 201-211 
    ISSN: 1432-0827
    Keywords: Autoradiography ; Calcium ; Oviduct ; Shell-gland
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Description / Table of Contents: Résumé La localisation cellulaire du calcium de la muqueuse de l'oviducte d'oiseaux a été étudiée par autoradiographie au45Ca, à partir de tissus préparés soit par incubation dans le45Ca, soit par injection intraveneuse du45Ca. La congélation — substitution est utilisée pour retenir le calcium aisément diffusible dans le tissu. L'épithelium cylindrique de la glande de la coquille s'enrichit significativement plus en45Cain vitro, en fonction de l'augmentation du temps d'incubation, de une à dix minutes et/ou en élevant la température de 0° à 42°. Ces effets sont diminués par l'adjonction de dinitrophenol au milieu d'incubation. Les glandes tubulaires de ce tissu réagissent à peine. Généralement, après injection intravenieuse de45Ca, la glande de la coquille retient plus de radionuclide que les autres régions de l'oviducte. Lorsqu'une coquille d'œuf est en voie de calcification, l'épithelium cylindrique de cette glande contient plus de grains que les glandes tubulaires, mais, en cas d'absence de formation d'œuf, le nombre de grains est identique dans les 2 types cellulaires. Il semble que l'épithélium cylindrique de la glande de la coquille a une affinité plus grande et plus variable pour le45Ca que la glande de la coquille les glandes tutulaires ou les cellules muqueuses d'autres régions de l'oviducte. Ces résultats indiquent sans le prouver, que l'épithélium cylindrique est plus actif dans le transfert du calcium des vaisseaux sanguins vers la lumière de la glande de la coquille.
    Abstract: Zusammenfassung Die celluläre Verteilung von Calcium in der Eileitermucosa von Hühnern wurde anhand von45Ca-Autoradiographien in Gewebe studiert, welches entweder durch Inkubation mit45Ca oder durch intravenöse Injektion von45Ca präpariert wurde. Gefriersubstitution wurde verwendet, um leicht diffundierbares Calcium im Gewebe zurückzuhalten.In vitro nahm das Cylinderepithel der Schalendrüse auffallend mehr45Ca auf, wenn die Inkubationszeit von einer auf zehn Minuten verlängert wurde und/oder wenn die Temperatur von 0° auf 42° erhöht wurde. Diese Wirkungen wurden durch die Zugabe von Dinitrophenol zum Inkubations-medium vermindert. Die Tubulärdrüsen dieses Gewebes reagierten kaum. Im allgemeinen schlossen die Schalendrüsen nach intravenöser Injektion von45Ca mehr Radionuklid ein als andere Teile des Eileiters. Wenn eine Eierschale calcifizierte, zeigte das Cylinderepithel der Schalendrüse bei der Autoradiographie eine höhere Anzahl von Silberkörnern als die Tubulärdrüsen, aber wenn keine Schale gebildet wurde, war sie bei beiden Zelltypen ähnlich. Die Resultate zeigen, daß das Cylinderepithel der Schalendrüse, eine größere und unterschiedlichere Affinität für45Ca hat als Schalendrüse Tubulärdrüsen oder Schleimhautzellen aus anderen Gebieten des Eileiters. Die Befunde deuten darauf hin, aber beweisen es nicht, daß das Cylinderepithel beim Transport von Calcium aus den Blutgefäßen in die Schalendrüse das aktivste ist.
    Notes: Abstract The cellular location of calcium in the mucosa of the avian oviduct has been studied by45Ca autoradiography in tissue prepared either by incubation with45Ca or by intravenous injection of45Ca. Freeze-substitution was used to retain easily diffusible calcium in the tissue.In vitro, columnar epithelium of the shell gland acquired significantly more45Ca as the length of incubation time was increased from one to ten minutes and/or when the temperature was raised from 0° to 42°. These effects were diminished by the addition of dinitrophenol to the incubation medium. The tubular glands of this tissue responded minimally. Genrally, after intravenous injection of45Ca, the shell gland sequestered, more radionuclide than the other regions of the oviduct. When an egg shell was being calcified, the columnar epithelium of the shell gland revealed a higher grain count than the tubular glands, but when a shell was not forming, grain counts were similar over the two types of cells. The results show that the columnar epithelium of the shell gland has a greater and more variable affinity for45Ca than have the shell gland tubular glands or mucosal cells from other regions of the oviduct. The data suggest, but do not prove, that the columnar epithelium is the most active in translocation of calcium from the blood vessels to the lumen of the shell gland.
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  • 2
    Electronic Resource
    Electronic Resource
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 62 (1996), S. 372-382 
    ISSN: 0730-2312
    Keywords: bFGF ; extracellular matrix ; in situ hybridization ; RT-PCR ; immunocytochemistry ; cell proliferation ; Western blotting ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Basic fibroblast growth factor (bFGF) is a permissive mitogen for cultured chondrocytes and has been localized in the specific zones of the epiphyseal growth plate. In this study, we demonstrate that bFGF present in cartilage originates from within the cellular constituents of this tissue. Utilizing reverse transcription coupled to the polymerase chain reaction (PCR), bFGF mRNA was found in extracts of cartilage tissue. Immunocytochemical studies revealed that bFGF was present intracellularly in freshly isolated proliferative chondrocytes and in the extracellular matrix (ECM) after 24 h of culture. Western blot analysis of protein extracts from isolated proliferative chondrocytes identified a bFGF immunoreactive species with a molecular weight of approximately 18 kDa. In situ hybridization confirmed the presence of bFGF mRNA in freshly isolated proliferative chondrocytes. The bFGF in the ECM seemed to be sequestered and not available for biological activity, since these cells still required exogenous bFGF for cell proliferation. This sequestered bFGF could be released to stimulate cell proliferation when cultures were treated with plasmin, a proteolytic enzyme. These data support the hypothesis that bFGF is synthesized by chondrocytes and functions as an autocrine/paracrine mitogen via its deposition into the ECM with subsequent release from the ECM of cartilage being a critical step in biological activity. In addition, the study provides further evidence that locally produced bFGF plays an important role in normal growth and development of cartilage tissue. © 1996 Wiley-Liss, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
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