Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Genomic Insertion of the SV-40 Large T Oncogene in Normal Adult Human Trabecular Osteoblastic Cells Induces Cell Growth Without Loss of the Differentiated Phenotype (1999)
    Springer
    Calcified tissue international 64 (1999), S. 394-401 
    Details
    ISSN: 1432-0827
    Keywords: Key words: Adult — Human — Immortalization — Trabecular osteoblasts — Mineralization.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Abstract. In the present study, we established a new adult human trabecular osteoblastic (AHTO) cell line, immortalized by SV-40 Large T (LT) oncogene. From seven proliferative colonies identified, we selected clone 7 with high alkaline phosphatase (ALP) activity for further analysis. AHTO−7 cells were able to grow for at least 8 months and 25 passages, with a doubling time of about 22 hours. Immunocytochemistry staining and RT-PCR analysis indicated that the extended life-span of AHTO−7 cells results in genomic insertion of SV-40 LT oncogene. The cells responded to PTH and PGE2 in terms of cAMP accumulation. The time course study, in the presence of 10−8 M vitamin D3 (vit D3) showed a marked increase (fourfold) in ALP activity with a peak at day 3. Furthermore, in the presence of ascorbic acid (50 μg/ml) and inorganic phosphate (3 mM), AHTO−7 cells produced abundant calcified extracellular matrix, as examined by the von Kossa staining after 2 weeks of culture. Molecular analysis of mRNAs for phenotypic osteoblast markers at day 15 showed the expression of ALP, osteocalcin (OC), and collagen type I (Col I) mRNAs constitutively. Col I expression was inhibited by vit D3 and dexamethasone treatment. In contrast, treatment with vit D3 induced a marked increase of ALP and OC transcripts. Therefore, the immortalized AHTO−7 cells express osteoblast markers that are induced by calciotropic hormones, and constitute a suitable model for identifying specific osteoblastic genes and their regulation during human osteoblast differentiation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00005821
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Congenital primary cutaneous osteoma: Biochemical and histological studies (1983)
    Springer
    Archives of dermatological research 275 (1983), S. 114-117 
    Details
    ISSN: 1432-069X
    Keywords: Cutaneous osteoma ; Collagen ; Ectopic osteogenesis ; Collagen crosslinks
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Biopsies of a cutaneous osteoma and of normal-looking skin from a 1-year-old girl were studied for histological appearance and collagen biochemistry. The mineralized tissue contained a matrix similar to bone: Only type I collagen, with a hydroxylysine content (0.48%) higher than in the skin (0.35%) and dihydroxylysinonorleucine as the major reducible crosslink. As expected, the normal skin adjacent to the lesions contained type I and type III collagen and as major crosslinks hydroxylysinonorleucine and histidinohydroxymerodesmosine. Histological studies showed the presence of woven bone with very little trabeculation. Numerous active osteoblasts were laying down a rapidly calcified non-lamellar matrix. Osteocytes and multinucleated osteoclasts were also noted. The study demonstrates the osseous nature of the lesion and suggests that an abnormal cell differentiation is associated with this form of osteoma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00412886
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Osteobiology, Strain, and Microgravity: Part I. Studies at the Cellular Level (2000)
    Springer
    Calcified tissue international 67 (2000), S. 2-9 
    Details
    ISSN: 1432-0827
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00223001088
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Alterations of matrix- and cell-associated proteoglycans inhibit osteogenesis and growth response to fibroblast growth factor-2 in cultured rat mandibular condyle and calvaria (1999)
    Springer
    Cell & tissue research 295 (1999), S. 523-536 
    Details
    ISSN: 1432-0878
    Keywords: Key words Chondroblasts ; Osteoblasts ; Bone formation ; β-d-Xyloside ; Chlorate ; Rat (Sprague Dawley)
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Matrix and cell surface proteoglycans (PGs) may play important roles in the control of cellular actions of heparan-binding growth factors such as fibroblast growth factor (FGF) during chondrogenesis and osteogenesis. In this study, we used 4-methylumbelliferyl-β−d-xyloside, an inhibitor of PG synthesis, and sodium chlorate, a competitive inhibitor of glycoconjugate sulfation, to determine the functional consequences of alterations of PG metabolism on osteogenesis and on FGF actions in neonatal rat condyle and calvaria in vitro. Biochemical analysis showed that β-d-xyloside (1 mM) or chlorate (15 mM) treatment for 1–8 days inhibited cellular PG synthesis by 60–80% in condyle and calvaria, as evaluated by [35S]sulfate incorporation. Histochemistry and immunohistochemistry showed that the inhibition of PG synthesis by β-d-xyloside resulted in reduced incorporation of chondroitin sulfate into cartilage and bone matrix. This was associated with a 75% reduction in cell growth in condyle, determined by DNA synthesis, and in collagenous matrix synthesis in condyle and calvaria, evaluated by tritiated proline incorporation and type I collagen immunohistochemistry. Morphological and quantitative autoradiographic analyses also showed that inhibition of PG synthesis by β-d-xyloside blocked bone matrix formation by perichondral progenitor cells in condyles and by osteoblasts in calvaria. In addition, alteration of PG metabolism blocked the mitogenic response to rhFGF-2 in calvaria. The data show that functional proteoglycans are essential for osteogenesis and for the growth response to FGF-2 during osteogenic differentiation in vitro.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s004410051258
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Temporal variation of c-fos proto-oncogene expression during osteoblast differentiation and osteogenesis in developing rat bone (1995)
    New York, N.Y. : Wiley-Blackwell
    Journal of Cellular Biochemistry 57 (1995), S. 62-70 
    Details
    ISSN: 0730-2312
    Keywords: c-fos ; calvaria ; femur ; osteogenesis ; proliferation ; differentiation ; osteoblast ; mRNA ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Chemistry and Pharmacology , Medicine
    Notes: To delineate the implication of c-fos protooncogenic in the osteogenie process, we have investigated the temporal pattern of c-fos mRNA expression in fetal and neonatal rat bone during intramembranous and endochondral bone formation. Northern blot analysis of mRNA extracted from calvaria and femur showed that expression of c-fos, Histone H4, and osteocalcin mRNAs followed a temporal sequence during bone development. The levels of histone H4 mRNA, a marker of cell proliferation, were high at early stages of fetal development of calvaria and femur, and decreased until birth. In both the postnatal calvaria and femur, c-fos mRNA levels increased transiently at birth and preceded a rise in osteocalcin transcripts, a marker of the mature osteoblast phenotype. The immunohistochemical analysis showed that c-fos protein was expressed in osteoprogenitor cells in the perichondrium and periosteum, and not in mature osteoblasts which expressed markers of differentiated osteoblasts such as type-I collagen, bone sialoprotein, and osteocalcin. Thus, the transient c-fos proto-oncogene expression during the postnatal life that precedes the osteocalcin expression may be involved in the transition from the precursor state to mature osteoblasts. These results suggest that c-fos proto-oncogene may play an important role in osteogenesis during rat postnatal life.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jcb.240570108
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...