Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Anatomy and embryology 188 (1993), S. 579-585 
    ISSN: 1432-0568
    Schlagwort(e): Human embryo ; Paraxial mesenchyme ; Sclerotome ; Lectins
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The paraxial mesenchyme in seven human embryos aged between Carnegie stages 12 and 17 was studied by lectin histochemistry with the lectins AIA, Con A, GSA II, LFA, LTA, PNA, RCA I, SBA, SNA, WGA. The paraxial mesenchyme was found to be segmented into sclerotomes by intersegmental vessels and from late stage 12 by intrasclerotomal clefts dividing each sclerotome into a cranial and caudal half. The lectins Con A, GSA II, LFA, LTA, SBA and SNA did not react at all in the paraxial mesenchyme. Staining for AIA, PNA, RCA I and WGA was found in the developing sclerotomes. However, no differences in the staining pattern between the two sclerotomal halves could be seen. It was striking that in contrast to the chick embryo no differences in binding for PNA between the cranial and caudal sclerotomal parts was observed. These findings reveal that PNA-binding sites do not play the same functional role in segmented axonal outgrowth and neural crest immigration into cranial sclerotomal halves in the human embryo, as found in chick embryonic development. Beginning with the stage 16-embryo, the already condensed caudal sclerotomal halves express Con A-, RCA- and PNA-binding sites. The staining for PNA in particular marked the differentiation of chondrogenous structures developing in this half. From the late stage 12 or stage 13, the walls of intersegmental and other vessels showed binding sites for AIA, PNA, RCA I, SNA and WGA.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Acta neuropathologica 83 (1992), S. 308-314 
    ISSN: 1432-0533
    Schlagwort(e): Large T-antigen ; Transgenic mice ; Pineal cell tumors ; Pineal organ ; Primitive neuroectodermal tumors
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Adult transgenic mice expressing the large T-antigen of the Simian virus 40 (SV 40) under the control of the Moloney murine sarcoma virus (MSV) enhancer and the SV 40 promoter develop inheritable uniform midline brain neoplasms showing features of primitive neuroectodermal tumors. The origin and histogenesis of these tumors were investigated in the present study. The brain and pineal organ of fetal and young transgenic mice less than 3 months old displayed normal macroscopic and microscopic features. In 3.5-month-old animals, the pineal organ was considerably enlarged due to hyperplasia, finally leading to tumor formation. Immunocytochemical demonstration of large T-antigen showed that this oncoprotein was already expressed in the nuclei of certain cells in the pineal organ of fetuses (16 and 18 days old) and newborn animals, but was absent from all other parts of the brain. The immunocytochemical demonstration of S-antigen (arrestin), a highly characteristic marker for pinealocytes, was used for further characterization of the large T-antigenimmunoreactive cells. The fetal pineal organ did not contain immunoreactive S-antigen. This first occurred in certain pinealocytes of newborn mice. Double immunostaining revealed that in newborn and older transgenic mice the immunoreactive large T-antigen was exclusively found in nuclei of cells containing S-antigen immunoreaction in their cytoplasm. Thus, transformed pinealocytes appear as stem cells of the experimental tumors. The results of this study suggest that primitive neuroectodermal tumors and the normal tissue from which they originate share certain molecular and immunocytochemical features.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Springer
    Anatomy and embryology 184 (1991), S. 345-353 
    ISSN: 1432-0568
    Schlagwort(e): Human embryo ; Lectins ; Spine ; Vertebral development
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary Paraffin sections from vertebral columns of ten human embryos and fetuses ranging from stage 16 to the 12th week were stained with the FITC-coupled lectins PNA, RCA I, Con A and WGA in order to investigate changes in carbohydrate-binding sites during vertebral development. PNA revealed a specific binding site in the vertebral body blastema in the precartilaginous stage of development. Beginning with the 25-mm CRL embryo, PNA-binding sites occurred in the developing fibrous annulus and the inner zone of the intervertebral discs. The first binding sites for RCA I were seen in the extracellular matrix of vertebral bodies during the cartilaginous stage of vertebral development. During early ossification of the vertebrae, staining for RCA I-binding sites in the cytoplasm of the chondrocytes and the area around the future cartilaginous end-plates was observed. Con A bound to the chondrocyte cytoplasm, and also very strongly to notochordal cells in all developmental stages examined. WGA-binding sites appeared simultaneously with cartilage formation. Connective tissue components, e.g. ligaments, were diffusely stained by WGA. Also this lectin showed an affinity for vertebral body chondrocytes. We discuss the biochemical aspects of these lectin-binding sites, and their possible roles in the differentiation process of the human vertebral column. The results of this first lectin histochemical study on human vertebral development are compared with related results in other species.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...