The Experts below are selected from a list of 34182 Experts worldwide ranked by ideXlab platform
Stanislaw Blazewicz - One of the best experts on this subject based on the ideXlab platform.
-
Bioactive Polymer/Hydroxyapatite (Nano)composites for Bone Tissue Regeneration
Advances in Polymer Science, 2010Co-Authors: Kinga Pielichowska, Stanislaw BlazewiczAbstract:Bioactive polymer/hydroxyapatite (nano)composites are currently being intensively investigated as materials for promotion of Bone Tissue Regeneration and reconstruction. The advantages of polymeric biomaterials, compared to metallic or ceramic materials, are the ease of manufacturing components having various and complex shapes, reasonable cost, and their ability to possess a wide range of physical and mechanical properties. Additionally, hydroxyapatite (HAp) is one of the most attractive materials for Bone implants because of its composition and biological similarity to natural Tissues. It can be obtained in a nanostructured form, which facilitates its fine dispersion in the polymer matrix as well as producing advantageous interactions with bioactive polymer and Tissue. This paper reviews recent advances in polymer/(nano)HAp composites and nanocomposites for Bone Tissue Regeneration, with particular emphasis on the material characteristics. Specific topics associated with polymer/HAp composition, molecular orientation and morphology, surface modifications, the interactions between the components, and their biological behaviours are described. Finally, the challenges facing this emerging field of research are outlined.
-
bioactive polymer hydroxyapatite nano composites for Bone Tissue Regeneration
Advances in Polymer Science, 2010Co-Authors: Kinga Pielichowska, Stanislaw BlazewiczAbstract:Bioactive polymer/hydroxyapatite (nano)composites are currently being intensively investigated as materials for promotion of Bone Tissue Regeneration and reconstruction. The advantages of polymeric biomaterials, compared to metallic or ceramic materials, are the ease of manufacturing components having various and complex shapes, reasonable cost, and their ability to possess a wide range of physical and mechanical properties. Additionally, hydroxyapatite (HAp) is one of the most attractive materials for Bone implants because of its composition and biological similarity to natural Tissues. It can be obtained in a nanostructured form, which facilitates its fine dispersion in the polymer matrix as well as producing advantageous interactions with bioactive polymer and Tissue. This paper reviews recent advances in polymer/(nano)HAp composites and nanocomposites for Bone Tissue Regeneration, with particular emphasis on the material characteristics. Specific topics associated with polymer/HAp composition, molecular orientation and morphology, surface modifications, the interactions between the components, and their biological behaviours are described. Finally, the challenges facing this emerging field of research are outlined.
Geunhyung Kim - One of the best experts on this subject based on the ideXlab platform.
-
Preparation and characterization of gelatin/α-TCP/SF biocomposite scaffold for Bone Tissue Regeneration
International Journal of Biological Macromolecules, 2017Co-Authors: Juntae Huh, Jiun Lee, Wonjin Kim, Miji Yeo, Geunhyung KimAbstract:In this study, we suggest a new biocomposite scaffold composed of gelatin/α-TCP (tricalcium phosphate)/SF (silk-fibroin) (GTS) which has enhanced mechanical strength and high level of cellular activity. To fabricate GTS scaffold, a temperature-controlled 3D printing process was used and appropriate printing conditions were selected based on rheological data. To show the feasibility as a biomedical scaffold for Bone Tissue Regeneration, the various physical and biological results, using MG63 (osteoblast-like cells), of the GTS scaffold were compared with those of a pure gelatin (G) and gelatin/α-TCP (GT) composite scaffold. GTS scaffolds showed enhanced mechanical properties in dry and wet state compared to those of the G and GT scaffolds. Also, significantly high cell-proliferation and differentiation of MG63 cells were observed in the GTS scaffold. Therefore, the GTS composite scaffold will be one of highly potential biomaterials to be used in Bone Regeneration.
-
A mechanically improved virus-based hybrid scaffold for Bone Tissue Regeneration
RSC Advances, 2016Co-Authors: Jae Yoon Lee, Woo-jae Chung, Geunhyung KimAbstract:Appropriate mechanical and outstanding biological properties of biomedical scaffolds are prerequisites to successfully regenerate Bone Tissues. Here, we designed a hybrid scaffold consisting of microsized core–sheath struts based on chemically conjugated M13 bacteriophage (phage)/alginate and poly(e-caprolactone) (PCL). The filamentous phages were modified with the Arg-Gly-Asp (RGD) sequence and calcium-binding sites. The hybrid scaffold was a mesh-like core (PCL)–sheath (phage/alginate) structure (strut size = 434 ± 51 μm, pore size = 495 ± 23 μm, with completely interconnected pores). To evaluate the mechanical and in vitro biological properties using osteoblast-like (MG63) cells, we used two controls: pure alginate and RGD-modified alginate (R-A). The scaffolds were analyzed for various mechanical properties and biological activities (tensile property, protein absorption ability, biomineralization, in vitro cell responses, and osteogenic gene expression). The biomineralization and protein absorption ability of the hybrid scaffold were significantly higher than those of the R-A. Furthermore, the proliferation of viable cells and the level of osteogenic gene expression (alkaline phosphatase activity) of the hybrid scaffold using the chemically conjugated phage/alginate were significantly enhanced compared with the control scaffolds. Based on these results, we suggest that the M13 phage/PCL-based hybrid scaffold may have potential as a biomedical scaffold for use in Bone Tissue Regeneration.
-
Effects of offset values of solid freeform fabricated PCL–β-TCP scaffolds on mechanical properties and cellular activities in Bone Tissue Regeneration
Journal of Materials Chemistry, 2012Co-Authors: Myunggu Yeo, Carl G. Simon, Geunhyung KimAbstract:Scaffolds used in Bone Tissue Regeneration should have highly porous micro-architecture. In addition, they should have high mechanical properties and be biodegradable and biocompatible. In this respect, the solid freeform fabricated PCL–β-TCP scaffold has been widely applied in Bone Tissue Regeneration. In this study, we designed PCL–β-TCP (20 wt%) scaffolds with various offset values, so that the fabricated scaffolds showed five different pore sizes that were dependent on the offset value (0%, 25%, 50%, 75%, and 100%), which showed very similar porosity (about 62%), a square pore shape, and 100% pore interconnectivity. The fabricated scaffolds were assessed not only for physical properties, including calculated bending modulus and water-uptake ability, but also for biological capabilities by culturing osteoblast-like cells (MG63) for various offset values of the scaffolds. Compared with the no-offset scaffolds, the offset scaffolds (especially those with offset values of 50% and 100%) showed superior physical and biological improvements, such as higher bending modulus (maximum increase of 7%), cell-seeding efficiency, cell viability (increase of about 60%), ALP activity (increase of about 50%), and calcium deposition.
-
A new hybrid scaffold constructed of solid freeform-fabricated PCL struts and collagen struts for Bone Tissue Regeneration: fabrication, mechanical properties, and cellular activity
Journal of Materials Chemistry, 2012Co-Authors: Seunghyun Ahn, Yongbok Kim, Hyeongjin Lee, Geunhyung KimAbstract:We propose a new technique for the fabrication of hybrid scaffolds using melt-plotting and a low temperature plate. This method is useful for the fabrication of a scaffold composed of heterogeneous biomaterials. We applied the new technique to collagen and polycaprolactone (PCL), which are stacked in interdigitated struts in successive layers to acquire a three-dimensional (3D) shape. The fabricated scaffolds exhibited a two-phase structure consisting of collagen struts to enhance the biological activity and PCL struts to increase the mechanical stability. They also exhibited a pore size under 100% pore interconnectivity appropriate for Bone Tissue Regeneration. The fabricated hybrid scaffolds were assessed not only for mechanical properties, but also for biological capabilities by culturing osteoblast-like cells (MG63) on pure PCL, collagen, and hybrid scaffolds. Compared with the pure PCL scaffold, the hybrid scaffold exhibited higher biological activity, such as cell viability (an increase of about 27% at 7 days), alkaline phosphatase (ALP) activity (an increase of about 36% at 14 days), and calcium deposition. The pure collagen exhibited the highest value for most biological activities studied. In addition, the hybrid scaffolds exhibited a dramatic increase of Young's modulus compared to those of pure collagen scaffolds. These results suggest that this hybrid scaffold is potentially useful as a biomedical scaffold for Bone Tissue Regeneration.
-
Rapid-prototyped PCL/fucoidan composite scaffolds for Bone Tissue Regeneration: design, fabrication, and physical/biological properties
Journal of Materials Chemistry, 2011Co-Authors: Gyuhyun Jin, Geunhyung KimAbstract:Biomedical composite scaffolds consisting of poly(e-caprolactone) (PCL) and fucoidan (Fu) fabricated by a melt-plotting system can be applied as a potential scaffold for Bone Tissue Regeneration. In this study, the pore size and strut diameter of the layer-by-layer composite scaffolds were fixed at 305 μm and 300 ± 15 μm, respectively, and the effect of various compositions (3, 5, 10, 20 wt%) of fucoidan on the morphology, hydrophilic properties, water-absorption ability, and mechanical characterization of the scaffolds was evaluated. Through the water-contact angle and water-absorption abilities, the composite scaffolds complemented with fucoidan displayed dramatically increased hydrophilic properties and higher mechanical properties (22% increase of Young's modulus at 10 wt% of fucoidan) under limited compositions of fucoidan compared to the pure PCL scaffold. The in vitro biocompatibility of the scaffolds was examined using osteoblast-like-cells (MG63). Specifically, cellular proliferation and mineralization were assessed. Based on scanning electron microscope (SEM) images, the cells more easily adhered and grew on the surface of the PCL/Fu scaffolds, showing a 30% enhanced mineral deposition compared to the pure PCL scaffold after 14 days of cell culture. This result was due to the continuous release of fucoidan from the composite scaffold. These physical and biological results demonstrate that composite PCL/Fu scaffolds represent a potential biomaterial for enhancing Bone Tissue Regeneration.
Kinga Pielichowska - One of the best experts on this subject based on the ideXlab platform.
-
Bioactive Polymer/Hydroxyapatite (Nano)composites for Bone Tissue Regeneration
Advances in Polymer Science, 2010Co-Authors: Kinga Pielichowska, Stanislaw BlazewiczAbstract:Bioactive polymer/hydroxyapatite (nano)composites are currently being intensively investigated as materials for promotion of Bone Tissue Regeneration and reconstruction. The advantages of polymeric biomaterials, compared to metallic or ceramic materials, are the ease of manufacturing components having various and complex shapes, reasonable cost, and their ability to possess a wide range of physical and mechanical properties. Additionally, hydroxyapatite (HAp) is one of the most attractive materials for Bone implants because of its composition and biological similarity to natural Tissues. It can be obtained in a nanostructured form, which facilitates its fine dispersion in the polymer matrix as well as producing advantageous interactions with bioactive polymer and Tissue. This paper reviews recent advances in polymer/(nano)HAp composites and nanocomposites for Bone Tissue Regeneration, with particular emphasis on the material characteristics. Specific topics associated with polymer/HAp composition, molecular orientation and morphology, surface modifications, the interactions between the components, and their biological behaviours are described. Finally, the challenges facing this emerging field of research are outlined.
-
bioactive polymer hydroxyapatite nano composites for Bone Tissue Regeneration
Advances in Polymer Science, 2010Co-Authors: Kinga Pielichowska, Stanislaw BlazewiczAbstract:Bioactive polymer/hydroxyapatite (nano)composites are currently being intensively investigated as materials for promotion of Bone Tissue Regeneration and reconstruction. The advantages of polymeric biomaterials, compared to metallic or ceramic materials, are the ease of manufacturing components having various and complex shapes, reasonable cost, and their ability to possess a wide range of physical and mechanical properties. Additionally, hydroxyapatite (HAp) is one of the most attractive materials for Bone implants because of its composition and biological similarity to natural Tissues. It can be obtained in a nanostructured form, which facilitates its fine dispersion in the polymer matrix as well as producing advantageous interactions with bioactive polymer and Tissue. This paper reviews recent advances in polymer/(nano)HAp composites and nanocomposites for Bone Tissue Regeneration, with particular emphasis on the material characteristics. Specific topics associated with polymer/HAp composition, molecular orientation and morphology, surface modifications, the interactions between the components, and their biological behaviours are described. Finally, the challenges facing this emerging field of research are outlined.
Silvia Farè - One of the best experts on this subject based on the ideXlab platform.
-
polyurethane foam nano hydroxyapatite composite as a suitable scaffold for Bone Tissue Regeneration
Materials Science and Engineering: C, 2018Co-Authors: Masoumeh Meskinfam, S. Bertoldi, N. Albanese, A. Cerri, Maria Cristina Tanzi, Rana Imani, Nafiseh Baheiraei, Mehdi Farokhi, Silvia FarèAbstract:In Bone Tissue Regeneration, the use of biomineralized scaffolds to create the 3D porous structure needed for well-fitting with defect size and appropriate cell interactions, is a promising alternative to autologous and heterologous Bone grafts. Biomineralized polyurethane (PU) foams are here investigated as scaffold for Bone Tissue Regeneration. Biomineralization of the foams was carried out by activation of PU surface by a two steps procedure performed for different times (1 to 4 weeks). Scaffolds were investigated for morphological, chemico-physical and mechanical properties, as well as for in vitro interaction with rat Bone Marrow Mesenchymal Stem Cells (BMSCs). Untreated and biomineralized PU samples showed a homogenous morphology and regular pore size (average O=407μm). Phase and structure of formed calcium phosphates (CaPs) layer onto the PU foam were analyzed by Fourier Transform Infrared spectroscopy and X-ray diffraction, proving the formation of Bone-like nano hydroxyapatite. Biomineralization caused a significant increase of mechanical properties of treated foams compared to untreated ones. Biomineralization also affected the PU scaffold cytocompatibility providing a more appropriate surface for cell attachment and proliferation. Considering the obtained results, the proposed scaffold can be considered suitable for Bone Tissue Regeneration.
-
Polyurethane foam/nano hydroxyapatite composite as a suitable scaffold for Bone Tissue Regeneration.
Materials Science and Engineering: C, 2017Co-Authors: Masoumeh Meskinfam, S. Bertoldi, N. Albanese, A. Cerri, Maria Cristina Tanzi, Rana Imani, Nafiseh Baheiraei, Mehdi Farokhi, Silvia FarèAbstract:In Bone Tissue Regeneration, the use of biomineralized scaffolds to create the 3D porous structure needed for well-fitting with defect size and appropriate cell interactions, is a promising alternative to autologous and heterologous Bone grafts. Biomineralized polyurethane (PU) foams are here investigated as scaffold for Bone Tissue Regeneration. Biomineralization of the foams was carried out by activation of PU surface by a two steps procedure performed for different times (1 to 4 weeks). Scaffolds were investigated for morphological, chemico-physical and mechanical properties, as well as for in vitro interaction with rat Bone Marrow Mesenchymal Stem Cells (BMSCs). Untreated and biomineralized PU samples showed a homogenous morphology and regular pore size (average O=407μm). Phase and structure of formed calcium phosphates (CaPs) layer onto the PU foam were analyzed by Fourier Transform Infrared spectroscopy and X-ray diffraction, proving the formation of Bone-like nano hydroxyapatite. Biomineralization caused a significant increase of mechanical properties of treated foams compared to untreated ones. Biomineralization also affected the PU scaffold cytocompatibility providing a more appropriate surface for cell attachment and proliferation. Considering the obtained results, the proposed scaffold can be considered suitable for Bone Tissue Regeneration.
-
Influence of polymer molecular weight in osteoinductive composites for Bone Tissue Regeneration
Acta Biomaterialia, 2013Co-Authors: Davide Barbieri, Silvia Farè, Huipin Yuan, Xiaoman Luo, Dirk W. Grijpma, Joost D. De BruijnAbstract:In Bone Tissue Regeneration, certain polymer and calcium-phosphate-based composites have been reported to enhance some biological surface phenomena, facilitating osteoinduction. Although the crucial role of inorganic fillers in heterotopic Bone formation by such materials has been shown, no reports have been published on the potential effects the polymer phase may have. The present work starts from the assumption that the polymer molecular weight regulates the fluid uptake, which determines the hydrolysis rate and the occurrence of biological surface processes. Here, two composites were prepared by extruding two different molecular weight l/d,l-lactide copolymers with calcium phosphate apatite. The lower molecular weight copolymer allowed larger fluid uptake in the composite thereof, which was correlated with a higher capacity to adsorb proteins in vitro. Further, the large fluid absorption led to a quicker composite degradation that generated rougher surfaces and enhanced ion release. Following intramuscular implantation in sheep, only the composite with the lower molecular weight polymer could induce heterotopic Bone formation. Besides influencing the biological potential of composites, the molecular weight also regulated their viscoelastic behaviour under cyclic stresses. The results lead to the conclusion that designing biomaterials with appropriate physico-chemical characteristics is crucial for Bone Tissue Regeneration in mechanical load-bearing sites.
Luigi Fabrizio Rodella - One of the best experts on this subject based on the ideXlab platform.
-
Sodium-DNA for Bone Tissue Regeneration: An Experimental Study in Rat Calvaria.
BioMed Research International, 2017Co-Authors: Barbara Buffoli, Gaia Favero, Elisa Borsani, Ramon Boninsegna, Guido Sancassani, Mauro Labanca, Rita Rezzani, Pier Francesco Nocini, Massimo Albanese, Luigi Fabrizio RodellaAbstract:Surgical techniques in dental and maxillofacial surgery request fast Bone Tissue Regeneration, so there is a significant need to improve therapy for Bone Regeneration. Several studies have recently underlined the importance of nucleotides and nucleosides to increase cell proliferation and activity; in particular, the ability of polydeoxyribonucleotide (PDRN) to induce growth and activity of human osteoblasts was demonstrated. Sodium-DNA is the deoxyribonucleic acid (DNA) extracted from the gonadic Tissue of male sturgeon and then purified, depolymerized, and neutralized with sodium hydroxide. To date, there are no evidences about the use of Sodium-DNA for Bone Tissue Regeneration. Consequently, our question is about the efficacy of Sodium-DNA in Bone healing. For testing the role of Sodium-DNA in Bone healing we used a rat calvarial defect model. Sodium-DNA at different concentrations used alone or in association with Fibrin and/or Bio-Oss was used for healing treatments and the Bone healing process was evaluated by histomorphometric and immunohistochemical analyses. Our results suggested a positive effect of Sodium-DNA in Bone Regeneration, providing a useful protocol and a model for the future clinical evaluation of its osteogenic properties.
-
Different preparation of Sodium-DNA for Bone Tissue Regeneration
Italian journal of anatomy and embryology, 2014Co-Authors: Barbara Buffoli, Ramon Boninsegna, Guido Sancassani, Pier Francesco Nocini, Massimo Albanese, Luigi Fabrizio RodellaAbstract:Current strategies for Bone Tissue Regeneration involve the use of a wide range of biomaterials and synthetic Bone substitutes; among them, Sodium-DNA could represent a new chance considering its osteoinductive properties (Nakamura et al., 2000; Bowler et a., 2001; Guizzardi et al., 2003; Guizzardi et al., 2007). The aim of this study was to evaluate the regenerative properties of two different preparation of Sodium- DNA (paste or liquid form) in a rat calvarial defect model. The cranium of each rat was shaved and a skin incision from the naso-frontal area to the external occipital protuberance was performed. The skin and the subcutaneous Tissues were reflected to expose the full extent of the calvaria. Full-thickness 5X8 mm Bone skull defects were made on each parietal region using piezoelectric surgery. Bone defects were filled with Sodium-DNA (paste or liquid form, Veritas, Brescia, Italy) alone or mixed with Bio-Oss (Geistlich, Wolhusen, Switzerland). Histomorphometric evaluation of Bone Regeneration was performed at the end of the treatments. The data obtained showed a time-dependent active Bone healing process; however, differences in the use of past or liquid form were evident. These results suggest that Sodium-DNA could be considered an active biomaterial in Bone Regeneration, but an adequate formulation to obtain a better regenerative efficacy is needed.