ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    ISSN: 0021-9304
    Keywords: growth hormone ; biphasic calcium phosphate ; monocyte ; lipopolysaccharides ; cell degradation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: This study investigated the effects of human growth hormone (hGH) on the monocyte/macrophage lineage, the first cell population involved in degradation of calcium phosphate ceramic after in vivo implantation. Monocytes isolated from human blood were cultured on biphasic calcium pellets (200 mg) for 8 days in the presence of lipopolysaccharides (LPS, 0.5 μg/mL), hGH (10 and 50 ng/mL), or an association of LPS with hGH (10 and 50 ng/mL). Unlike LPS, hGH significantly decreased (about 25%) the total number of lacunae formed by monocytes. However, hGH induced the formation of lacunae with a greater surface area (about a 90% increase) as compared to the control. Finally, intense upmodulation (about a 250% increase) of lacuna surface area was observed in the presence of both soluble factors, suggesting that hGH and LPS act synergistically. In view of the development of a drug delivery system for hGH bone release, this study shows that hGH not only stimulates bone cells implicated in the synthesis of the extracellular matrix but also those involved in the early degradation of calcium phosphate biomaterial. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 40, 79-85, 1998.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 0021-9304
    Keywords: biphasic calcium phosphate ceramic ; monocyte ; lipopolysaccharides ; polymyxin B ; cell degradation ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Numerous cell types, such as monocytes and osteoclasts, are involved in calcified matrix degradation. In this context, calcium-phosphate ceramics present similar degradation processes in vivo and in vitro to those found in a natural calcified substrate. As the monocyte/macrophage lineage is among the first cells to appear in ceramic implantation sites, it is a key protagonist in inflammatory reaction and biodegradation mechanisms. This study investigated the ability of human monocytes/macrophages activated by various agents [lipopolysaccharides (LPS), polymyxin B (PMB)] to degrade biphasic calcium-phosphate ceramics. PMB sulfate is a bacteriostatic antibiotic that modulates LPS-induced cell activities in vivo and in vitro. Degradation pits (about 10 μm) produced on the pellet surface by these monocytes were discrete, with well defined margins. LPS increased the degradation of calcium-phosphate ceramic (number of lacunae, mean pellet surface area degraded) in a dose-dependent manner whereas polymyxin B downmodulated it significantly. The addition of 2 μg/mL of polymyxin B reduced the number of degradation lacunae and the extent of degraded surface area induced by 0.1 μg/mL LPS by 87% and 64%, respectively. Thus this cell culture system can be very useful in the study of cellular degradation of biomaterials and of the influence of therapeutic agents that may modulate these cell activities. © 1998 John Wiley & Sons, Inc. J. Biomed Mater Res, 40, 336-340, 1998
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: This study aims at evaluating bone growth in critical-sized femoral defects of rats filledwith macro micro porous biphasic calcium phosphate ceramic (MBCP) cylinders surrounded or notby a resorbable collagen membrane. Femoral defects left empty (control) exhibited partial boneingrowths after 3 and 6 weeks and were completely healed at 12 weeks. The defects filled with thecollagen membranes appeared partially healed suggesting that the membranes constraint boneingrowth. Bone formation occurred around the collagen membrane which partially degraded overtime. In the MBCP/membrane group, bone has grown inside the macro pores of the MBCPcylinders. Bone ingrowth was more rapid and abundant in the defects filled with MBCP alone. Thecombination MBCP/collagen membrane may be beneficial for the reconstruction of large bonedefects without using repetitive surgeries and autologous bone grafting
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...