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Full-Text Articles in Engineering
In Vitro Comparative Biocompatibility Testing Of Carbofilm Coated And Uncoated Polyetherimide For Cardiovascular Application, M. Bosetti, S. Mazzarelli, L. Nicolais, L. Ambrosio, M. Cannas
In Vitro Comparative Biocompatibility Testing Of Carbofilm Coated And Uncoated Polyetherimide For Cardiovascular Application, M. Bosetti, S. Mazzarelli, L. Nicolais, L. Ambrosio, M. Cannas
Cells and Materials
When blood contacts the surface of a material, several processes take place including the activation of coagulation and immune systems. The aim of this work is to study in vitro the biological reactions seen from the point of view of hemocompatibility and cytocompatibility of a new polymer suggested as an artificial surface for cardiovascular applications: Carbofilm® coated polyetherimide (C®PEI) in comparison to polyetherimide (PEI), the uncoated form. PEI and C®PEI showed no signs of acute cytotoxicity although following long term incubation with PEI cytotoxicity was somewhat increased; both materials supported good endothelial cell adhesion with a higher level of cell …
Effects Of Solidification Conditions And Heat Treatment On The Microstructure And Vickers Hardness Of Pd-Cu-Ga Dental Alloys, William A. Brantley, Zhuo Cai, Stanley G. Vermilyea, Efstratios Papazoglou, John C. Mitchell, Alan B. Carr
Effects Of Solidification Conditions And Heat Treatment On The Microstructure And Vickers Hardness Of Pd-Cu-Ga Dental Alloys, William A. Brantley, Zhuo Cai, Stanley G. Vermilyea, Efstratios Papazoglou, John C. Mitchell, Alan B. Carr
Cells and Materials
Two representative Pd-Cu-Ga dental alloys, one with a dendritic as-cast microstructure containing a eutectic interdendritic constituent and the other with an equiaxed fine-grained as-cast microstructure containing a near-surface eutectic constituent, have been subjected to rapid quenching following casting, in addition to the conventional bench cooling recommended by the manufacturers. The quenched alloys were subsequently heat treated at temperatures of 1200°, 1500° and 1800 op that span the range of the firing cycles for dental porcelain. Scanning electron microscopic examination showed that the lamellar eutectic constituents normally present in the microstructures of the as-cast and bench-cooled alloys persisted when the alloys …
Letter To The Editor: Biocompatibility And Reactogenicity Of Materials: A Semantic And Logical Analysis Of Definitions And Their Practical Significance, Leonid I. Slutskii, Janis J. Vetra
Letter To The Editor: Biocompatibility And Reactogenicity Of Materials: A Semantic And Logical Analysis Of Definitions And Their Practical Significance, Leonid I. Slutskii, Janis J. Vetra
Cells and Materials
Any biomaterial implanted into a living body elicits a distinct local reaction. This reaction depends on the physical, physico-chemical and chemical properties of the material. The obvious term to designate this inherent property of a biomaterial to induce a local reaction is reactogenicity. Reactogenicity of a biomaterial is one of the main factors determining (together with other properties of the implanted device) the bio(non)compatibility of the implant. Such amplification of terminology which establishes differences between biocompatibility as a generalized characteristic of biomaterials in all their interrelations with the host's organism and the influences on local processes around implants, makes the …
Albumin Affinity Biomaterial Surfaces, James R. Keogh, John W. Eaton
Albumin Affinity Biomaterial Surfaces, James R. Keogh, John W. Eaton
Cells and Materials
Recently, considerable progress has been made in designing biomaterial surfaces which possess enhanced albumin affinity. Two derivatization methods for producing albumin binding biomaterial surfaces, based on an albumin affinity dye, cibacron blue, have been developed. Both surface derivatization methods were found to enhance the binding of albumin to an implant grade polyetherurethane. Evaluations of the enhanced albumin affinity demonstrated the binding to be both selective and reversible. Surfaces having such enhanced albumin affinity were found to be minimally thrombogenic and to discourage the adhesion of bacteria which might otherwise cause device-centered infections. We conclude that albumin affinity surfaces, such as …
Scanning Electron Microscopy Studies Of Ceramic Layers And Interfacial Regions For Calcium Phosphate-Coated Titanium Dental Implants, W. A. Brantley, E. Tufecki, J. C. Mitchell, D. W. Foreman, E. A. Mcglumphy
Scanning Electron Microscopy Studies Of Ceramic Layers And Interfacial Regions For Calcium Phosphate-Coated Titanium Dental Implants, W. A. Brantley, E. Tufecki, J. C. Mitchell, D. W. Foreman, E. A. Mcglumphy
Cells and Materials
The surface and cross-section characteristics of the plasma-sprayed calcium phosphate coatings, along with the microstructures and elemental compositions near the titanium alloy interface, were investigated by scanning electron microscopy for two different dental implants of proprietary compositions: Integra!® (Calcitek) and BioVent ® (Dentsply). Elemental concentrations (Ca, P, Ti, AI, and V) near the interfaces were obtained by X-ray energy-dispersive spectroscopy. Coating surfaces exhibited a splat deposition topography of greatly differing microstructural scale for the two implants, along with other features characteristic of the plasma-spraying process; cross-sections of the coatings revealed minimal porosity. Some interdiffusion of principally titanium and calcium was …
Room Temperature Aging Of Pd-Cu-Ga Dental Alloys, William A. Brantley, Zhuo Cai, Qiang Wu, Alan B. Carr, John C. Mitchell
Room Temperature Aging Of Pd-Cu-Ga Dental Alloys, William A. Brantley, Zhuo Cai, Qiang Wu, Alan B. Carr, John C. Mitchell
Cells and Materials
Specimens of three Pd-Cu-Ga dental alloys cast five years ago and subsequently stored at room temperature were reexamined and observed to have lower amounts of the eutectic constituents in the near-surface region than originally present, along with other microstructural changes. This previously unreported room temperature aging behavior of these alloys is attributed to the presence of high-diffusivity paths in the non-equilibrium ascast eutectic structures and to the essential role of the surface for the vacancy diffusion mechanism. These results may have important clinical significance for the ill vivo corrosion resistance and long-term biocompatibility of the Pd-Cu-Ga alloys.
Attachment Kinetics And Differentiations Of Osteoblasts On Different Biomaterials, U. Meyer, D. H. Szulczewski, K Moller, H. Heide, D. B. Jones
Attachment Kinetics And Differentiations Of Osteoblasts On Different Biomaterials, U. Meyer, D. H. Szulczewski, K Moller, H. Heide, D. B. Jones
Cells and Materials
Primary bovine osteoblast cell cultures were used to study the response of osteoblasts ton three different biomaterials, ionomeric cement (IC), tri-calcium phosphate poly-L-lactic acid composite foil (TCP) and poly-L-lactate-polycitric acid composite foil (PLA). The cells which grew on the materials produced all typical bone matrix proteins and were osteoblast-Iike as shown by immuno-staining. Analysis of the cell attachment kinetics revealed significant differences within the first 7 hours between the various materials. The best rate of cell attachment was found on the IC surface, followed by the TCP and then the PLA surface. The kinetics of attach ment appeared to be …
Intravital Microscopic Evidence That Polylactide-Polyglycolide (Plga) Delays Neo-Osteogenesis And Neo-Angiogenesis In Healing Bone, H. Winet, J. O. Hollinger
Intravital Microscopic Evidence That Polylactide-Polyglycolide (Plga) Delays Neo-Osteogenesis And Neo-Angiogenesis In Healing Bone, H. Winet, J. O. Hollinger
Cells and Materials
The bone chamber implant (BCI) has allowed monitoring a healing bone defect as well as the effect of an eroding implant on the healing process. The BCI is a useful tool and intravital microscopy a valuable technique for obtaining quantitative data chronicling osseous wound healing. The physiological parameters that form the initial data base documenting healing are neo-osteogenesis and neo-angiogenesis. This review compares and characterizes osseous wound healing in a BCI loaded with an erodible copolymer, PLGA (polylactide-polyglycolide). To determine if a statistically significant deviation from normal healing had occurred, the results were compared with present and historical controls. In …
Analysis Of Protein Adsorption On Retrieved Human Vascular Grafts Using Immunogold Labelling With Silver Enhancement, N. P. Ziats, N. S. Topham, D. A. Pankowsky, J. M. Anderson
Analysis Of Protein Adsorption On Retrieved Human Vascular Grafts Using Immunogold Labelling With Silver Enhancement, N. P. Ziats, N. S. Topham, D. A. Pankowsky, J. M. Anderson
Cells and Materials
The adsorption of proteins on biomedical materials such as vascular grafts is important in modulating thrombosis, one eventual cause of vascular graft failure. We have identified proteins expressed on the surfaces of retrieved vascular grafts to determine if certain proteins were present at the end stage of vascular failure. Scanning electron microscopic analysis of protein adsorption on the surfaces of retrieved vascular prostheses was determined using antibodies to human blood proteins fibrinogen, fibronectin, Hageman factor (factor XII) and factor VIII/von Willebrand Factor. The detection of these proteins on the blood contacting surface was evaluated by immunogold labelling with protein A-gold …