Apatite Nucleation on Low Porosity Silicon in Acellular Simulated Body Fluids

MRS Proceedings ◽

10.1557/proc-414-189 ◽

1995 ◽

Vol 414 ◽

Cited By ~ 4

Author(s):

L T Canham ◽

C L Reeves

Keyword(s):

Body Fluids ◽

Porous Si ◽

Bioactive Materials ◽

Simulated Body Fluids ◽

Low Levels ◽

Si Films ◽

Insight Into ◽

Low Porosity

AbstractThe response of a range of porous Si films to acellular simulated body fluids has been monitored by SEM, EDX and FTIR analyses. Quite low levels of porosity are shown here to induce hydroxyapatite growth both on top of the film, and even on neighbouring areas of bulk Si, which in isolation have no such effect. The in-vitro demonstration of hydroxyapatite nucleation by a porous semiconductor could provide further insight into the phenomenon of bioactivity and help realise a broader range of bioactive materials.

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Silicon as an Active Biomaterial

MRS Proceedings ◽

10.1557/proc-452-579 ◽

1996 ◽

Vol 452 ◽

Cited By ~ 12

Author(s):

L. T. Canham ◽

C. L. Reeves ◽

D. J. Wallis ◽

J. P. Newey ◽

M. R. Houlton ◽

...

Keyword(s):

Body Fluids ◽

Bulk Silicon ◽

Porous Si ◽

Vlsi Technology ◽

Simulated Body Fluids ◽

Silicon Microstructures ◽

Si Films ◽

In Vivo Assessment

AbstractThe response of a range of porous Si and poly Si films to storage in acellular simulated body fluids is summarised and its implications discussed. It is suggested that the combination of VLSI technology, micromachining and surface microstructuring achievable with silicon, could establish this prominent semiconductor as a very useful biomaterial by the next century. The ‘biocompatibility’ of a variety of silicon microstructures, and even bulk silicon has received surprisingly little study, but now warrants detailed in-vitro and in-vivo assessment.

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Bioactivity of Silver Doped Hydroxyapatite Scaffolds in Simulated Body Fluids

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.604.175 ◽

2014 ◽

Vol 604 ◽

pp. 175-179 ◽

Cited By ~ 1

Author(s):

Lasma Poca ◽

Arita Dubnika ◽

Dagnija Loca ◽

Liga Berzina-Cimdina

Keyword(s):

Simulated Body Fluid ◽

Incubation Period ◽

Powder Diffraction ◽

Body Fluid ◽

Body Fluids ◽

Apatite Layer ◽

X Ray ◽

Simulated Body Fluids ◽

Two Phases

In the present study, thein vitrobioactivity of silver-doped hydroxyapatite (HAp/Ag) scaffolds was investigated. HAp/Ag was prepared using two different modified wet precipitation methods. The X-ray powder diffraction (XRD) results showed, that sintered HAp/Ag samples prepared using method (I) contain two phases HAp and Ag, but samples prepared by method (II) contain three different phases - HAp, Ag and AgO. After 2 month incubation period in simulated body fluid (SBF), surface of HAp/Ag scaffolds was coated with bone-like apatite. Thickness of bone-like apatite layer increased from 2 μm up to 32 μm, increasing the incubation period.

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The emergence of classical BSE from atypical/Nor98 scrapie

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1915737116 ◽

2019 ◽

Vol 116 (52) ◽

pp. 26853-26862 ◽

Cited By ~ 6

Author(s):

Alvina Huor ◽

Juan Carlos Espinosa ◽

Enric Vidal ◽

Hervé Cassard ◽

Jean-Yves Douet ◽

...

Keyword(s):

Prion Disease ◽

Protein Misfolding ◽

Small Ruminants ◽

Public Health Perspective ◽

Prion Strain ◽

Low Levels ◽

Insight Into ◽

New Occurrences

Atypical/Nor98 scrapie (AS) is a prion disease of small ruminants. Currently there are no efficient measures to control this form of prion disease, and, importantly, the zoonotic potential and the risk that AS might represent for other farmed animal species remains largely unknown. In this study, we investigated the capacity of AS to propagate in bovine PrP transgenic mice. Unexpectedly, the transmission of AS isolates originating from 5 different European countries to bovine PrP mice resulted in the propagation of the classical BSE (c-BSE) agent. Detection of prion seeding activity in vitro by protein misfolding cyclic amplification (PMCA) demonstrated that low levels of the c-BSE agent were present in the original AS isolates. C-BSE prion seeding activity was also detected in brain tissue of ovine PrP mice inoculated with limiting dilutions (endpoint titration) of ovine AS isolates. These results are consistent with the emergence and replication of c-BSE prions during the in vivo propagation of AS isolates in the natural host. These data also indicate that c-BSE prions, a known zonotic agent in humans, can emerge as a dominant prion strain during passage of AS between different species. These findings provide an unprecedented insight into the evolution of mammalian prion strain properties triggered by intra- and interspecies passage. From a public health perspective, the presence of c-BSE in AS isolates suggest that cattle exposure to small ruminant tissues and products could lead to new occurrences of c-BSE.

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In vitro biomineralization of a novel hydroxyapatite/superhydrophilic multiwalled carbon nanotube nanocomposite using simulated body fluids

Materials Research ◽

10.1590/s1516-14392013005000038 ◽

2013 ◽

Vol 16 (3) ◽

pp. 650-654

Author(s):

Marcele Florencio Neves ◽

Tayra Rodrigues Brazil ◽

Eduardo Silva Soares ◽

Evaldo Jose Corat ◽

Fernanda Roberta Marciano ◽

...

Keyword(s):

Carbon Nanotube ◽

Body Fluids ◽

Multiwalled Carbon Nanotube ◽

Multiwalled Carbon ◽

Simulated Body Fluids

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Genetic, Genomic, and Functional Analysis of the Granule Lattice Proteins in Tetrahymena Secretory Granules

Molecular Biology of the Cell ◽

10.1091/mbc.e05-01-0028 ◽

2005 ◽

Vol 16 (9) ◽

pp. 4046-4060 ◽

Cited By ~ 21

Author(s):

Andrew T. Cowan ◽

Grant R. Bowman ◽

Kyle F. Edwards ◽

J. J. Emerson ◽

Aaron P. Turkewitz

Keyword(s):

Secretory Granules ◽

Subtle Change ◽

Epistasis Analysis ◽

Granule Morphology ◽

Low Levels ◽

Lattice Proteins ◽

Insight Into ◽

In Vitro Data

In some cells, the polypeptides stored in dense core secretory granules condense as ordered arrays. In ciliates such as Tetrahymena thermophila, the resulting crystals function as projectiles, expanding upon exocytosis. Isolation of granule contents previously defined five Granule lattice (Grl) proteins as abundant core constituents, whereas a functional screen identified a sixth family member. We have now expanded this screen to identify the nonredundant components required for projectile assembly. The results, further supported by gene disruption experiments, indicate that six Grl proteins define the core structure. Both in vivo and in vitro data indicate that core assembly begins in the endoplasmic reticulum with formation of specific hetero-oligomeric Grl proprotein complexes. Four additional GRL-like genes were found in the T. thermophila genome. Grl2p and Grl6p are targeted to granules, but the transcripts are present at low levels and neither is essential for core assembly. The ΔGRL6 cells nonetheless showed a subtle change in granule morphology and a marked reduction in granule accumulation. Epistasis analysis suggests this results from accelerated loss of ΔGRL6 granules, rather than from decreased synthesis. Our results not only provide insight into the organization of Grl-based granule cores but also imply that the functions of Grl proteins extend beyond core assembly.

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Biological Activity of rhBMP-2 Released From PLGA Microspheres

Journal of Biomechanical Engineering ◽

10.1115/1.429662 ◽

2000 ◽

Vol 122 (3) ◽

pp. 289-292 ◽

Cited By ~ 75

Author(s):

J. B. Oldham, ◽

L. Lu, ◽

X. Zhu, and ◽

B. D. Porter ◽

T. E. Hefferan ◽

...

Keyword(s):

Bone Regeneration ◽

Body Fluids ◽

Bone Morphogenetic Protein 2 ◽

In Vitro Tests ◽

Plga Microspheres ◽

Skeletal Tissue ◽

Morphogenetic Protein ◽

Biodegradable Poly ◽

Simulated Body Fluids

Human recombinant bone morphogenetic protein-2 (rhBMP-2) has been proven effective in stimulating the regeneration of bone in both skeletal and extraskeletal locations. Through encapsulation within, and release from, biodegradable poly(DL-lactic-co-glycolic acid) (PLGA) microspheres, a proven vehicle for sustained delivery of various proteins, the local concentrations of rhBMP-2 could be maintained at optimal levels to stimulate bone regeneration and remodeling at the site of healing in diverse clinical settings. Thus the purpose of this work was to investigate the encapsulation of rhBMP-2 in PLGA microspheres and its biologic activity upon release. Using in vitro tests in simulated body fluids, the effect of rhBMP-2 released from PLGA microspheres upon osteoblast cell cultures was found to be statistically similar to the effect produced by positive controls consisting of nonencapsulated aqueous rhBMP-2 in simulated body fluids. This clarifies an important step in skeletal tissue engineering strategies aimed at the use of encapsulated rhBMP-2 to stimulate bone regeneration and remodeling. [S0148-0731(00)01303-0]

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Perspectives of Silicone Elastomere Implants Use in Preventing Postoperative Complications in Pelvic Exenteration for Advanced Cancers

Revista de Chimie ◽

10.37358/rc.20.1.7809 ◽

2020 ◽

Vol 71 (1) ◽

pp. 45-50

Author(s):

George Jinescu ◽

Nicolae Bacalbasa ◽

Andra Evtodiev ◽

Iulia-Adelina Marin ◽

Ioana Chiulan ◽

...

Keyword(s):

Mechanical Performance ◽

Degradation Products ◽

Hydrolytic Degradation ◽

Hardness Measurement ◽

Body Fluids ◽

Time Interval ◽

Swine Model ◽

Simulated Body Fluids

In this work, silicone elastomer films with potential to be used as implantable pelvic prosthesis were prepared and their bioactivity was studied both in vitro and in vivo environment. Tensile tests, hardness measurement and compression analysis revealed no significant decrease of the mechanical performance after in vitro hydrolytic degradation in simulated body fluids. The in vivo biocompatibility of films was assessed by implanting them subcutaneously in swine model, for 30 days. Their mechanical characteristics were similar to those of samples immersed in simulated body fluids, for the same time interval. No sign of fibrosis or necrosis were detected from the histological analysis performed on the tissue surrounding the films. In combination, these results indicate that this material has a very good resistance to mechanical and chemical fatigue, do not release any toxic degradation products and, therefore, has great potential as to be used further for preparation of pelvic prosthesis.

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Combined Structural Investigations of Bioactive Silicate Glasses

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.361-363.257 ◽

2007 ◽

Vol 361-363 ◽

pp. 257-260 ◽

Cited By ~ 1

Author(s):

Frank Malz ◽

H. Aguiar ◽

Eugenio Luís Solla ◽

Julia Serra ◽

Pio González ◽

...

Keyword(s):

Silicate Glass ◽

Body Fluids ◽

Silicate Glasses ◽

In Vitro Tests ◽

Structural Investigations ◽

Structural Characterisation ◽

Simulated Body Fluids

The results of a combined structural characterisation (XRD, IR, NMR, SEM, TEM) of a phosphate containing Mg-Ca silicate and a phosphate containing Na-Ca silicate glass samples are presented. The structural results are also compared with in vitro tests carried out in simulated body fluids for checking bioactivity.

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