ALBERT — All Library Books, journals and Electronic Records Telegrafenberg

1

Electronic Resource

Bone morphogenetic protein and ceramic-induced osteogenesis (1998)

Yuan, Huipin ; Zou, Ping ; Yang, Zongjian ; [et al.]

Springer

Journal of materials science 9 (1998), S. 717-721

add to mindlist on the mindlist

Details

ISSN: 1573-4838

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine , Technology

Notes: Abstract To investigate the relationship between bone morphogenetic proteins (BMP) and calcium phosphate ceramic-induced osteogenesis in soft tissues, in vitro and in vivo experiments were performed. In an in vitro study, the ability of different calcium phosphate ceramics to absorb bovine BMP (bBMP) from a bBMP solution was tested. In vivo studies included immunohistochemical BMP staining before bone formation in the ceramics was detected, and the enhancement of bone formation in calcium phosphate ceramics by bBMP. The results were: (1) calcium phosphate ceramics have a strong ability to absorb bBMP; (2) a high BMP concentration reaches inside the ceramic implants before bone formation in soft tissues of domestic pig occurs; (3) by 56% at 50 d and by 23% at 100 d, bBMP enhances bone formation in calcium phosphate ceramics implanted in soft tissues of dogs. The results indicate the BMP plays an important role in calcium phosphate ceramic-induced osteogenesis and that adsorption of native BMP from the body fluids to ceramic implants may be a key step in osteoinduction by calcium phosphate ceramics © 1998 Kluwer Academic Publishers

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1008998817977

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

2

Electronic Resource

Osteoinduction by calcium phosphate biomaterials (1998)

Yuan, Huipin ; Yang, Zongjian ; Li, Yubao ; [et al.]

Springer

Journal of materials science 9 (1998), S. 723-726

add to mindlist on the mindlist

Details

ISSN: 1573-4838

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine , Technology

Notes: Abstract Different materials were implanted in muscles of dogs to study the osteoinduction of calcium phosphate biomaterials. Bone formation was only seen in calcium phosphate biomaterials with micropores, and could be found in hydroxyapatite (HA) ceramic, tricalcium phosphate/hydroxyapatite ceramic (BCP), β-TCP ceramic and calcium phosphate cement. The osteoinductive potential was different in different materials. The results indicate that osteoinduction can be a property of calcium phosphate biomaterials when they exhibit specific chemical and structural characteristics. © 1998 Kluwer Academic Publishers

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1008950902047

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

3

Electronic Resource

In vivo bone formation by human bone marrow cells: effect of osteogenic culture supplements and cell densities (1998)

Mendes, S. C. ; Van Den Brink, I. ; De Bruijn, J. D. ; [et al.]

Springer

Journal of materials science 9 (1998), S. 855-858

add to mindlist on the mindlist

Details

ISSN: 1573-4838

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine , Technology

Notes: Abstract Bone marrow is known to contain a population of osteoprogenitor cells that can go through complete differentiation when cultured in a medium containing appropriate bioactive factors. In this study, porous particles of a calcium phosphate material were seeded with adult human bone marrow cells in the second passage. After an additional culture period of 1 wk in the particles, these hybrid constructs were subcutaneouslly implanted in nude mice with a survival period of 4 wk. The cell seeding densities range from 0–200 000 cells per particle and the cell culture system was designed to investigate the single and combined effects of dexamethasone and recombinant human bone morphogenetic protein 2 (rhBMP-2). The hybrid “material/tissue” constructs were processed for histology and the amount of de novo bone formation was quantified, for each culture condition, by histomorphometric techniques. The relative percentage of mineralized bone formation reached a maximal value of 19.77±5.06, for samples cultured in the presence of rhBMP-2 and with a seeding density of 200 000 cells/particle, compared to 0.52±0.45 for samples in which no cells had been cultured and had been incubated in culture medium supplemented with Dex and rhBMP-2. For the tested conditions and for the low cell numbers used in this study, rhBMP-2 proved to be an essential bioactive factor to obtain in vivo bone formation by our culture system. The results from this study prove the potential of cultured adult human bone marrow cells to initiate and accelerate de novo bone formation after transplantation into an ectopic site. © 1998 Kluwer Academic Publishers

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1008904413859

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

4

Electronic Resource

Bone tissue engineering on calcium phosphate-coated titanium plates utilizing cultured rat bone marrow cells: a preliminary study (1998)

Dekker, R. J. ; De Bruijn, J. D. ; Van Den Brink, I. ; [et al.]

Springer

Journal of materials science 9 (1998), S. 859-863

add to mindlist on the mindlist

Details

ISSN: 1573-4838

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine , Technology

Notes: Abstract The use of osteoinductive in vitro tissue-coated implants in orthopaedic and dental surgery (e.g. revision hip arthroplasty), could result in a better fixation of these implants. However, this tissue engineering technology has only proved to be effective in porous materials and not on flat implant surfaces. In this study we have demonstrated that calcium phosphate-coated titanium plates with a layer of cultured osteogenic cells and their extracellular matrix can initiate bone formation in vivo. Both primary and subcultured rat bone marrow cells were grown on to biomimetic calcium phosphate-coated titanium plates. After 7 d of culture, in the presence or absence of dexamethasone, the implants were subcutaneously implanted in nude mice for 4 wk. Control samples, which consisted of calcium phosphate-coated plates without cultured cells and porous calcium phosphate particles with or without cultured cells, were also implanted subcutaneously. At autopsy, no bone formation could be detected on any of the control samples without cells and samples with subcultured cells, which were primary cultured in medium without dexamethasone. In contrast, clear de novo bone formation could be observed on the calcium phosphate-coated plates and in the porous calcium phosphate particles with primary or subcultured cells, which had been continuously cultured in medium with dexamethasone. These results indicate that this hybrid technology offers great potential for the fixation of flat bone replacement implants (e.g. artificial hips) in inferior bone in the future. © 1998 Kluwer Academic Publishers

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1008956430697

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

5

Electronic Resource

Comparison of the cytotoxicity of molybdenum as powder and as alloying element in a niobium–molybdenum alloy (1998)

Pypen, C. M. J. M. ; Dessein, K. ; Helsen, J. A. ; [et al.]

Springer

Journal of materials science 9 (1998), S. 761-765

add to mindlist on the mindlist

Details

ISSN: 1573-4838

Source: Springer Online Journal Archives 1860-2000

Topics: Medicine , Technology

Notes: Abstract Commercially pure metal niobium (c.p. Nb) as well as niobium–molybdenum (Nb–Mo) alloys were produced following several powder metallurgical routes. In brief, niobium and molybdenum powders were blended and milled in order to form Nb–Mo alloys. The alloy powders and the c.p. Nb were then either pressed and sintered, or cold isostatically pressed followed by hot isostatically pressing. In order to assess the cytotoxicity of the c.p. Nb and c.p. Mo powders, a 72 h minimal essential medium-extraction test was performed according to ISO/EN 10993–5. The cytotoxicity of the c.p. Nb metal and the Nb–Mo alloys was tested in a 72 h direct contact test. Compared to a negative control (UHMWPE), c.p. Nb was non-toxic, but c.p. Mo was moderately toxic. None of the powder metallurgically produced materials were toxic. Neither differences in molybdenum concentration, nor in porosity of the samples, due to different production routes, had any influence on the toxicity of the materials. Rat bone marrow cultures showed that only on c.p. Nb was a mineralized extracellular matrix formed, while on the more porous Nb–Mo alloys, cell growth was observed, but no mineralization. In conclusion, c.p. Mo powder is moderately toxic, however, as an alloying element it is non-toxic. Material porosity seems to influence differentiation of bone tissue in vitro. © 1998 Kluwer Academic Publishers

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1023/A:1008919422520

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

6

Electronic Resource

Initial bone matrix formation at the hydroxyapatite interface in vivo (1995)

de Bruijn, J. D. ; van Blitterswijk, C. A. ; Davies, J. E.

Hoboken, NJ : Wiley-Blackwell

Journal of Biomedical Materials Research 29 (1995), S. 89-99

add to mindlist on the mindlist

Details

ISSN: 0021-9304

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Medicine , Technology

Notes: Dense, sintered, slip-cast hydroxyapatite rods were implanted transfemorally in young adult rats. The femora were excised after 2 and 4 weeks and, following fixation, either embedded in methyl methacrylate for light microscopy, decalcified and prepared for transmission electron microscopy, or freeze fractured in liquid nitrogen for scanning electron microscopic analysis. The latter was performed on the two tissue fragments that remained after freeze fracturing, from which the first contained the implants and the second comprised tissue that had been immediately adjacent to the hydroxyapatite rods. Undecalcified light microscopic sections revealed extensive bone tissue formation around and in contact with the hydroxyapatite rods. The initial bone matrix apposed to the implant surface, as demonstrated with scanning electron microscopy, was either composed of globular deposits or an organized network of collagen fibers. The deposits, which ranged in size from 0.1-1.1 μm, fused to form a cement-like matrix to which collagen fibers were attached. Degradation of the hydroxyapatite surface resulted in the presence of unidirectionally aligned crystallites, with which the newly formed bone matrix was closely associated. Ultrastructural analysis of the bone-hydroxyapatite interface with transmission electron microscopy revealed a 50-600-nm-wide collagen-free granular zone, comprising one or more 40-100-nm-thick electron-dense layer(s). These structural arrangements most probably partially represent the globular deposits and proteinaceous material adsorbed onto and partially in the degrading hydroxyapatite surface. Although the latter change in surface topography may have enhanced bonding of the cement-like matrix to the hydroxyapatite, the cause for this change in topography and the type of bond formed are, at present, unknown. © 1995 John Wiley & Sons, Inc.

Additional Material: 11 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/jbm.820290113

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

7

Electronic Resource

Decreased consumption of Ca and P during in vitro biomineralization and biologically induced deposition of Ni and Cr in presence of stainless steel corrosion products (1998)

Morais, S. ; Sousa, J. P. ; Fernandes, M. H. ; [et al.]

Hoboken, NJ : Wiley-Blackwell

Journal of Biomedical Materials Research 42 (1998), S. 199-212

add to mindlist on the mindlist

Details

ISSN: 0021-9304

Keywords: osteoblast-like cells ; mineralization ; stainless steel corrosion products ; Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Medicine , Technology

Notes: The purpose of this study was to investigate the effects of 316L stainless steel (SS) corrosion products on the in vitro biomineralization process, because tissue necrosis, bone loss, impaired bone mineralization, and loosening of orthopedic implants are associated with ions and debris resulting from biodegradation. Rat bone marrow cells were cultured in experimental conditions that favored the proliferation and differentiation of osteoblastic cells and were exposed to SS corrosion products obtained by electrochemical means for periods ranging from 1 to 21 days. Quantification of total and ionized Ca and P, as well as Fe, Cr, and Ni, ions in the culture media of control and metal added cultures during the incubation period was performed to study the influence of corrosion products on the Ca and P consumption that occurs during the mineralization process. Control cultures and metal effects on cultures were evaluated concerning DNA content, enzymatic reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and alkaline phosphatase (ALP) activity. Histochemical detection of ALP, Ca, and phosphate deposition, and examination of the cultures by scanning and transmission electron microscopy (SEM and TEM) were also performed. The presence of SS corrosion products resulted in impairment of the normal behavior of rat bone marrow cultures. Levels of Cr and Ni in the medium of cultures exposed to 316L SS corrosion products decreased throughout the incubation period, suggesting a regular deposition of these species; these results were supported by TEM observation of the cultures. Cultures exposed to the corrosion products presented lower DNA content, MTT reduction, and ALP activity and failed to form mineralized areas. These cultures showed negative staining on histochemical reactions for the identification of calcium and phosphate deposition and SEM and TEM examination did not show mineral globular structures or mineralization foci, respectively, which is characteristic of cultures grown in control conditions. These results suggest that metal ions associated with 316L SS are toxic to osteogenic cells, affecting their proliferation and differentiation. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 42, 199-212, 1998.

Additional Material: 9 Ill.

Type of Medium: Electronic Resource

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

8

Electronic Resource

Osteoclastic resorption of calcium phosphates is potentiated in postosteogenic culture conditions (1994)

de Bruijn, J. D. ; Bovell, Y. P. ; Davies, J. E. ; [et al.]

Hoboken, NJ : Wiley-Blackwell

Journal of Biomedical Materials Research 28 (1994), S. 105-112

add to mindlist on the mindlist

Details

ISSN: 0021-9304

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Medicine , Technology

Notes: Cell-mediated resorption of densely sintered hydroxyapatite (HA1250), tricalcium phosphate (TCP), and 600° or 900°C calcined hydroxyapatite (HA600 and HA900, respectively), was investigated by using two culture systems. The first was an osteoclastic cell culture, and the second was a two-stage culture that was composed of a bonelike tissue formation on the substrata in the first stage and its subsequent resorption by osteoclasts in the second stage. Neither of the materials showed resorption or surface alterations in the osteoclastic cell culture, except for some limited phagocytotic activity on HA600 and HA900. In the two-stage culture, production of mineralized extracellular matrix was only observed on HA1250 and TCP, and its subsequent resorption by osteoclastlike cells was evident. Small and occasionally larger tartrate-resistant acid phosphatase positive cells produced 20-150 μm diameter resorption pits in both the mineralized extracellular matrix on HA1250 and TCP and TCP and the surfaces of HA600 and HA900. Resorption of the mineralized extracellular matrix on TCP also resulted in degradation of the underlying ceramic surface, mainly initiating from intergrain boundaries, whereas the surface of HA1250 remained unaltered. The results of this study clearly demonstrate that osteoclastic resorption of calcium phosphates is potentiated in postosteogenic culture conditions. A possible role for bone matrix constituents in cell-mediated resorption is hypothesized, whereas the occurrence of resorption seems to be mainly governed by the combined effects of material characteristics such as grain size and crystal structure. © 1994 John Wiley & Sons, Inc.

Additional Material: 7 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/jbm.820280114

Permalink

	Location	Call Number	Expected	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

9

Electronic Resource

The ultrastructure of the bone-hydroxyapatite interface in vitro (1992)

de Bruijn, J. D. ; Klein, C. P. A. T. ; de Groot, K. ; [et al.]

Hoboken, NJ : Wiley-Blackwell

Journal of Biomedical Materials Research 26 (1992), S. 1365-1382

add to mindlist on the mindlist

Details

ISSN: 0021-9304

Keywords: Chemistry ; Polymer and Materials Science

Source: Wiley InterScience Backfile Collection 1832-2000

Topics: Medicine , Technology

Notes: Rat bone marrow cells were cultured on plasma-sprayed hydroxyapatite (HA). The cells formed a mineralized extracellular matrix (ECM) that exhibited several characteristics of bone tissue. The interface between this mineralized ECM and the HA was studied at the ultrastructural level with scanning and transmission electron microscopy and x-ray microanalysis. Initially, the deposition of a globular, afibrillar matrix was observed on HA. This was followed by the integration of collagen fibers in this matrix and their subsequent mineralization. At the bone-HA interface two distinctly different interfacial structures were observed. An electron-dense layer with a thickness of 20-60 nm was regularly present, which contained both organic and inorganic material and was rich in glycosaminoglycans. The interfaces differed however, in the presence or absence of an amorphous zone which was free of collagen fibers and had an average thickness of 0.7-0.8 μm. It was frequently seen interposed between the electron-dense layer and the hydroxyapatite. Similar interfacial structures have also been described in the in vivo environment, where they were referred to as lamina limitans-like or cement linelike. From the results of this study, it can be concluded that the described in vitro system is a suitable model to study bonebiomaterial interactions. © 1992 John Wiley & Sons, Inc.

Additional Material: 12 Ill.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1002/jbm.820261008

Permalink