Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Cellular fatty acid-binding proteins (FABP) are a highly conserved family of proteins consisting of several subtypes, among them the mammary-derived growth inhibitor (MDGI) which is quite homologous to or even identical with the heart-type FABP (H-FABP). The FABPs and MDGI have been suggested to be involved in intracellular fatty acid metabolism and trafficking. Recently, evidence for growth and differentiation regulating properties of MDGI and H-FABP was provided. Using four affinity-purified polyclonal antibodies against bovine and human antigen preparations, the cellular localization of MDGI/H-FABP in human and mouse tissues and organs was studied. The antibodies were weakly cross-reactive with adipose tissue extracts known to lack H-FABP, but failed to react by Western blot analysis with liver-type FABP (L-FABP) and intestinal-type FABP (I-FABP). MDGI/H-FABP protein was mainly detected in myocardium, skeletal and smooth muscle fibres, lipid and/or steroid synthesising cells (adrenals, Leydig cells, sebaceous glands, lactating mammary gland) and terminally differentiated epithelia of the respiratory, intestinal and urogenital tracts. The results provide evidence that expression of H-FABP is associated with an irreversibly postmitotic and terminally differentiated status of cells. Since all the antisera employed showed spatially identical and qualitatively equal immunostaining, it is suggested that human, bovine and mouse MDGI/H-FABP proteins share highly homologous epitopes.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1573-7217
    Keywords: breast cancer ; EGF binding ; growth rate ; mitoses ; nodal status
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Number of mitoses and EGF binding were determined in parallel in biopsies of 27 lymph-node positive and of 23 lymph-node negative breast cancer patients. For node-positive patients the parameters for cell growth and EGF binding were quantitatively correlated by the equation y = P3 + P1(1 − exp( − P2x)). For node-negative cases neither the non-linear model nor the linear approximation described the data unambiguously. The results strongly suggest that in node-positive patients, growth of breast cancer is related to an EGF-dependent acceleration of cell division.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0730-2312
    Keywords: EGF derivative ; EGF receptor ; cytochemical detection ; clinical oncology ; tumor marker ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: A biotinylated derivative of murine epidermal growth factor (EGF) was prepared by covalent attachment of the terminal amino group of EGF to N-biotinyl-ε-aminocaproyl-N-hydroxysuccinimide. The stoichiometry of biotin incorporation was in the range of one biotin moiety per EGF molecule. The biotinylated EGF (biotinyl-ε-caproyl-EGF, BioEGF) binds to EGF receptors on intact Ehrlich ascites carcinoma (EAC) cells with an affinity similar to that of native EGF and displays the same mitogenic activity as EGF in a soft agar test system with normal rat kidney (NRK) cells. BioEGF was visualized on cultured cells and tissue sections of a head and neck tumour by commercial streptavidin/avidin detection systems. Cytochemical analyses of certain tumour forms can be easily performed using the BioEGF probe.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    ISSN: 0730-2312
    Keywords: explant culture ; stimulation of DNA synthesis ; inhibition of functional differentiation ; endogenous TGFα ; arachidonic acid release ; phospholipase A2 ; metabolic inhibitors ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: Epidermal growth factor (EGF) has been suggested to be involved in mammary gland development by mitogenic stimulation of the ductal and alveolar epithelium in virgin mice. The present studies demonstrate that also in late-pregnant mice EGF leads to proliferation of the ductal, ductular, and alveolar epithelium. The mitogenic effect is associated with structural and functional dedifferentiation of alveolar cells as revealed by analysis of morphology, expression of cytosolic and secretory proteins, and fatty acid synthesis. Using a combination of metabolic inhibitors, the dedifferentiating effect of EGF could be blocked while the mitogenic action was not influenced. This finding demonstrates that the signal transduction pathway leading to dedifferentiation and mitosis can be separated, and that the dedifferentiating effect of EGF is independent of its mitogenic properties, but is probably mediated by activation of the arachidonic acid-dependent pathways (cyclo- and lipoxygenase pathways). Release of arachidonic acid from the endogenous phospholipid pool was found to be an early response of the explants to EGF. Accordingly, arachidonic acid itself proved to be capable of inducing epithelial dedifferentiation but failed to stimulate proliferation. TGFα showed qualitatively similar effects as EGF but was generally a stronger agonist. It is suggested that EGF and TGFα also play a role in mammary gland physiology during pregnancy by final developing and maintanance of the lobulo-alveolar structure in the mammary gland and prevention of premature onset of lactation, and that this is mediated through the PLA2-arachidonic acid signalling cascade.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0021-9541
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Antiprogestins possess a potent antitumor activity in hormone-dependent experimental breast cancer models. Though the underlying mechanism is not clear, induction of functional differentiation seems to be a major event. This study attempts to test directly for antiproliferative and differentiation promoting activities of antiprogestins on the normal mammary gland. To this end, whole organ cultures of mammary glands from estradiol/progesterone-primed virgin mice maintained in a serum-free medium with aldosterone, prolactin, insulin, and hydrocortisone were exposed to the antiprogestin ZK114043. A 4-day treatment of organ cultures led to a strong inhibition of epithelial DNA synthesis. In parallel, ZK114043 caused alveolar cells to acquire a more differentiated phenotype distinguished by secretory active alveoli composed of single cell layers with increased fat droplet accumulation and enhanced expression of the milk proteins b̃-casein and whey acidic protein (WAP). Particularly strong effects were found on the expression of mammary-derived growth inhibitor (MDGI). Both half-maximal inhibition of epithelial DNA synthesis and stimulation of MDGI mRNA expression were found at about 5 ng/ml of ZK114043. Presence in the medium of 5 m̈g/ml hydrocortisone rendered antiglucocorticoid effects of ZK114043 highly unlikely. Furthermore, prevention of action of ZK114043 by the progesterone agonist R5020 and ZK114043 stimulated expression of b̃-casein and MDGI mRNA in cultured glands of 10-week-old unprimed virgin mice suggest a progesterone receptor-mediated mechanism of antiprogestin action. Two other antiprogestins, Mifepristone and Onapristone, likewise stimulated MDGI expression. The data provide direct evidence that antiprogestins act like a differentiation factor in the normal mammary gland. © 1995 Wiley-Liss, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...