Search results for "Biocompatible Materials"
showing 10 items of 243 documents
Fibronectin-mediated endothelialisation of chitosan porous matrices.
2009
Chitosan (Ch) porous matrices were investigated regarding their ability to be colonized by human microvascular endothelial cells (HPMEC-ST1.6R cell line) and macrovascular endothelial cells namely HUVECs. Specifically we assessed if previous incubation of Ch in a fibronectin (FN) solution was effective in promoting endothelial cell (EC) adhesion to Ch matrices with different degrees of acetylation (DAs). Upon FN physiadsorption, marked differences were found between the two DAs investigated, namely DA 4% and 15%. While cell adhesion was impaired on Ch with DA 15%, ECs were able to not only adhere to Ch with DA 4%, but also to spread and colonize the scaffolds, with retention of the EC pheno…
Influence of polymer content in Ca-deficient hydroxyapatite–polycaprolactone nanocomposites on the formation of microvessel-like structures
2009
Calcium phosphate (CaP) ceramics are widely used in bone tissue engineering due to their good osteoconductivity. The mechanical properties of CaP can be modified by the addition of small volume fractions of biodegradable polymers such as polycaprolactone (PCL). Nevertheless, it is also important to evaluate how the polymer content influences cell-material or cell-cell interactions because of potential consequences for bone regeneration and vascularization. In this study we assessed the general biocompatibilty of Ca-deficient hydroxyapatite (CDHA)-PCL disks containing nominally 11 and 24% polycaprolactone using human umbilical vein endothelial cells and human primary osteoblasts. Confocal mi…
Vascularization and gene regulation of human endothelial cells growing on porous polyethersulfone (PES) hollow fiber membranes.
2004
Abstract Open-cell hollow fibers made of polyethersulfone (PES) manufactured in the absence of solvents with pore diameters smaller than 100 μm were examined for vascularization by human endothelial cells. The goal of this study was to determine whether the 3-D porous character of the PES surface affected human endothelial cell morphology and functions. Freshly isolated human endothelial cells from the skin (HDMEC), from the lung (HPMEC) and from umbilical cords (HUVEC) and two human endothelial cell lines, HPMEC-ST1.6R and ISO-HAS.c1 were added to PES fibers and cell adherence and growth was followed by confocal laser scanning microscopy. Prior coating of PES with gelatin or fibronectin wa…
Dynamic In Vivo Biocompatibility of Angiogenic Peptide Amphiphile Nanofibers
2009
Biomaterials that promote angiogenesis have great potential in regenerative medicine for rapid revascularization of damaged tissue, survival of transplanted cells, and healing of chronic wounds. Supramolecular nanofibers formed by self-assembly of a heparin-binding peptide amphiphile and heparan sulfate-like glycosaminoglycans were evaluated here using a dorsal skinfold chamber model to dynamically monitor the interaction between the nanofiber gel and the microcirculation, representing a novel application of this model. We paired this model with a conventional subcutaneous implantation model for static histological assessment of the interactions between the gel and host tissue. In the stati…
Tailoring the stealth properties of biocompatible polysaccharide nanocontainers.
2014
Fundamental development of a biocompatible and degradable nanocarrier platform based on hydroxyethyl starch (HES) is reported. HES is a derivative of starch and possesses both high biocompatibility and improved stability against enzymatic degradation; it is used to prepare nanocapsules via the polyaddition reaction at the interface of water nanodroplets dispersed in an organic miniemulsion. The synthesized hollow nanocapsules can be loaded with hydrophilic guests in its aqueous core, tuned in size, chemically functionalized in various pathways, and show high shelf life stability. The surface of the HES nanocapsules is further functionalized with poly(ethylene glycol) via different chemistri…
Biocompatibility of New Pulp-capping Materials NeoMTA Plus, MTA Repair HP, and Biodentine on Human Dental Pulp Stem Cells
2017
The aim of the present study was to evaluate the in vitro cytotoxicity of MTA Repair HP, NeoMTA Plus, and Biodentine, new bioactive materials used for dental pulp capping, on human dental pulp stem cells (hDPSCs).Biological testing was carried out in vitro on hDPSCs. Cell viability and cell migration assays were performed using eluates of each capping material. To evaluate cell morphology and cell attachment to the different materials, hDPSCs were directly seeded onto the material surfaces and analyzed by scanning electron microscopy. The chemical composition of the pulp-capping materials was determined by energy-dispersive X-ray and eluates were analyzed by inductively coupled plasma-mass …
Software-supported image quantification of angiogenesis in an in vitro culture system: application to studies of biocompatibility
2002
Healing of soft tissue trauma and bone discontinuities following implantation involves acute inflammatory reactions and the formation of blood vessels (angiogenesis). During angiogenesis new capillary vessels arise from the existing vasculature. Endothelial cells (EC) are the major cell type involved in angiogenesis. Corrosion of orthopaedic metallic implant materials (e.g. CoCr alloys) can cause locally high concentrations of heavy metal ions in the peri-implant tissues. Some divalent metal ions (Co2+, Ni2+, Zn2+) lead to the activation of EC in vitro. Upon exposure to these ions. EC release cytokines and chemokines and increase the expression of cell surface adhesion molecules, which repr…
New generation super alloy candidates for medical applications: Corrosion behavior, cation release and biological evaluation
2014
Three super alloy candidates (X1 CrNiMoMnW 24-22-6-3-2 N, NiCr21 MoNbFe 8-3-5 AlTi, CoNiCr 35-20 Mo 10 BTi) for a prolonged contact with skin are evaluated in comparison with two reference austenitic stainless steels 316L and 904L. Several electrochemical parameters were measured and determined (E(oc), E(corr), i(corr), b(a), b(c), E(b), R(p), E(crev) and coulometric analysis) in order to compare the corrosion behavior. The cation release evaluation and in vitro biological characterization also were performed. In terms of corrosion, the results reveal that the 904L steels presented the best behavior followed by the super austenitic steel X1 CrNiMoMnW 24-22-6-3-2 N. For the other two super a…
Modification of human platelet adhesion on biomaterial surfaces by protein preadsorption under static and flow conditions.
2004
Biomaterial-induced thrombosis remains one of the main complications of vascular implant devices. Preadsorbed proteins on the biomaterial/blood interface will modify the adhesion and activation of platelets (PTLs) during the initial contact-phase. Our results clearly show that PTL-adherence on biomaterials is influenced not only by protein preadsorption, but also by flow conditions. The covalent coating of TCPS and glass by phosphorylcholine (PC) induces a significant decrease of PTL adhesion but leads to a slight, but nevertheless significant activation of PTL, which was detected by the induction of P-selectin expression using FACS analysis. Methodologically, the visualization of PTL adhes…
The effect of electrochemically simulated titanium cathodic corrosion products on ROS production and metabolic activity of osteoblasts and monocytes/…
2006
Nowadays aseptic loosening is the most common cause of orthopaedic implant failure. Some of its reasons have already been described up to now; however, others remain still hypothetical. Besides the inflammatory response to wear particles originating at different sources, the role of reactive oxygen species as products of cellular reactions and/or as a result of the process of corrosion of an implant leading to implant failure has recently been discussed too. In the present study, we used a galvanostatic polarization to simulate the cathodic partial reaction of the corrosion process at a titanium alloy surface. With respect to cells occurring at the interface of a metal implant, the behaviou…