2,988 research outputs found

    Intelligent Computing in Medical Ultrasonic System

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    兵庫県立大学大学院201

    Surface Modification of Ti Implant for Enhancing Biotribology and Cells Attachment

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    Implant success strongly depends on the proper integration of bone to biomaterial surface. By the selected retrieval cases, inadequate integration of bone screws was a dominated factor caused failure. The surface modification technology that improve osteointegration by inducing TiO2 nanotubes (NT) on Ti-based implants has a potential applications in orthopaedic implants. NT generated by anodization method provide a vertically aligned nanotube structure that enhances the integration between bone tissue and implant surface by improving osteoblasts attachment. Although cells to NT is positive, the mechanical weakness of NT has also been well-documented and is an obstacle to its applications. The thesis comprise a detailed method to improve NT mechanical stability, by introducing an interfacial bonding layer at NT bottom and Ti substrate, and retaining vertically aligned nanotubes. The physicochemical properties of this structure optimized TiO2 nanotubes (SO-NT) was systematically characterized, the SO-NT has been demonstrated with improved biotribological and biocorrosive performance. The uniform hyperfine interfacial bonding layer with nano-sized grains exhibited a strong bonding to NT layer and Ti substrate. It was observed, the layer not only effectively dissipates external impacts and shear stress but also acts as a good corrosion resistance barrier to prevent the Ti substrate from corrosion. The SO-NT modified bone screw has also demonstrated with enhanced fretting corrosion resistance than NT and pristine Ti6Al4V on screws. Since the elongated osteoblasts were observed on NT and SO-NT compared with Ti surface, the nanotubes structure has been shown with promoting of osteoblasts attachment. However, the mechanism of cell nanotubes interactions are largely in controversial. In order to reveal the cell-nanomaterial interactions, nanotopographies including Nanoconvex, Nanoconcave and Nanoflat were generated and characterized to evaluate the cell initial attachment behaviour. Human osteoblasts were observed with spindle shape on Nanoconcave, cells on Nanoflat were well-spreading but in sphere shape, while the osteoblasts on Nanoconvex were with the minimum spreading areas. Cell-materials interface is mediated and influenced by the adsorption of ECM on nanomaterials. Thus, a novel fibronectin adsorption model was proposed by calculating Coulomb's force to illustrate the interact mechanism between protein and material that influence cell behaviours. The achievements of thesis are; 1. Retrieval analyzed two cases of implants failure and pointed out one of dominated failure factor, the lack of osteointegration. 2. Introduce the interfacial bonding layer that significantly improve the biotribological and biocorrosive performance of NT, and generated SO-NT. 3. Systematically evaluated the biotribological performance of Ti, NT and SO-NT, and propose a novel methodology to quantify the fretting degradation on bone screws. 4. Propose a novel model to estimate the fibronectin adsorption on Nanoflat, Nanoconvex and Nanoconcave by the Coulomb's force calculation

    Development and properties of multifunctional biomedical nanocomposites(多機能生体医療用ナノコンポジットの創成およびその特性に関する研究)

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    信州大学(Shinshu university)博士(工学)ThesisYU JUHONG. Development and properties of multifunctional biomedical nanocomposites(多機能生体医療用ナノコンポジットの創成およびその特性に関する研究). 信州大学, 2018, 博士論文. 博士(工学), 甲第680号, 平成30年03月20日授与.doctoral thesi

    Implant-prosthetic therapy failure in smoker and nonsmoker patients

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    Introduction: Implant-prosthetic therapy has predictable success, and the complications are associated with a lot of factors. Smoking cigarettes is reason for different oral diseases, bone loss, loss of soft tissue and teeth, appearance of periimplantitis and implant loss. The corellation of smoking and implant-prosthetic therapy failure was examined in the clinical study. Materials and method: Fifty patients with FDP on 61 implants in frontal and molar region were investigated. They were divided in two groups: smokers and nonsmokers. Thirty four patients were smokers, and sixteen didn’t smoke cigarettes in the last two years. Criteria data for the success of the therapy were mobility of the implant, pain, peri-implant bone loss higher than 1.5 mm, absence of technical complications and function and aesthetics appeal. Control checkups were made after six months, one and two years. Patients had questionnaires, clinical examination and X-ray. Results: There is a statistically significant difference between smokers and nonsmokers in the failure rates of dental implants. During first year 0,5 mm of bone was lost around eleven implants, and 0,05 mm next years.Total seven implants failed, five in smoker group at the beginning of the first year, and 2 in nonsmoker group during second year. Conclusion: Results showed that smoking habit can increase the risk of early implants loss two times more often in smokers. For some complications like periimplantitis, local factors have greater influence. Smoking does not increase the risk of late implant loss, but the implants at patients with smoking habit, in correlation with several different local risk factors, is contraindicated. Early complications are results of smoking, while quality and quantity of surrounding bone are responsible for late complications.The results from the investigation, also give informations for proper treatment planning, and patient education for quiting their harmfull habit. Keywords Implants, therapy failure, smoking, periimplantitis

    Biologization, Nanotechnology, Simulation: Proceedings of the 1st Joint PhD Conference on Material Science:: from 27.6.-1.7.2022 in Dresden/ Germany and Usti/Česká republika

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    Materials scientists from Ústí nad Labem and Dresden met in June of 2022 for the first joint PhD Conference on Material Science, with the special focus on biologization, nanotechnology and simulation. The conference aimed to encourage interdisciplinary exchange between Čzech and German research institutes and promote transnational cooperation on an international level along the Saxon- Čzech border. Due to the restrictions caused by the corona pandemic, several attempts were necessary before the conference, which was first planned in 2020, could finally take place for the first time in 2022. The conference could take place in presence, which was seen as a big plus by all participants, especially as it was the first meeting in this German - Čzech context for most of the participants. The attending scientists (about 60) met at the Institute of Material Science of TU Dresden in Germany for the first half of the week before the conference moved to the faculties of Science and Environment of the Jan Evangelista Purkyně University UJEP in Ústí nad Labem in Čzechia. The organized activities ranged from scientific presentations of current PhD projects and research topics, lab tours in the participating institutions, come-together events such as a guided tour at the dye collection of the TU Dresden and a hiking trip to Bohemian Switzerland. The conference was funded by INTERREG VA Saxony - Čzech Republic - a cooperation programme of the Elbe/Labe region. All participants - PhD students, scientists and staff members of the participating institutions - enjoyed this opportunity to build individual and new contacts, exchange information on current research topics and methods, find starting points for future collaborations between the different research areas and institutions and also discuss the similarities and differences between the German and Čzech research landscape. The purpose of this brochure is to present the institutions with their special topics and laboratories and to present current research topics - on the base of the presented PhD projects.:1 Introduction 2 1.1 Committees 5 2 Presentation of the participating institutes and chairs 5 2.1 Jan Evangelista Purkyně University in Ústí nad Labem 6 2.1.1 Faculty of Science 6 2.1.2 Faculty of Environment 12 2.2 Technische Universität Dresden 17 2.2.1 Institute of Material Science 17 2.3 Fraunhofer Institute for Ceramic Technologies and Systems IKTS 19 2.3.1 Department Bio- and Nanotechnology at IKTS 19 2.4 Institute for Complex Materials, Leibniz-IFW Dresden 21 2.5 TRANS³Net 22 3 Presentation of the PhD topics 23 3.1 Topic: BIOLOGIZATION 23 3.1.1 Ludovico Andrea Alberta: Exploring the effect of Cu additions on the mechanical behaviour of β-TiNb biomaterials 23 3.1.2 Franziska Alt: Formation of a microenvironment for directed differentiation of stem cells in a perfusion bioreactor 25 3.1.3 Dmitry Belyaev: Circular microfluidic systems for electro-chemical continuous monitoring of bio-chemicals in emulsion droplets 27 3.1.4 Constantin Ißleib: Dynamic osteoimmunological crosstalk in a bone replacement context 28 3.1.5 Adela Jagerová: Surface Modification by High-Energy Heavy-Ion Irradiation in Various Crystalline ZnO Facets 29 3.1.6 Nils Kaube: Bioinspired development of artificial enamel via in-situ nano-mineralization 30 3.1.7 Michaela Kocholata: Isolation and characterization of plant derived nanovesicles 30 3.1.8 Zuzana Nejedlá: Dendrimers as Drug Delivery System 31 3.1.9 Jacub Perner: Effect of cold plasma treatment of Poppy and Proso Millet seeds in plasma downer 32 3.1.10 Marina Roshchina: Development of new bacteria-killing coatings on beta-Ti-Nb alloy based on functional oxide nanotubular (ONT) layers 33 3.1.11 Muhammad Saqib: Algorithms and fluid-dynamic experimental platform for in vitro degradation studies of implant materials 34 3.1.12 Jacub Tolasz: Interaction of pollutants on nanoceria 35 3.1.13 Zuzana Žmudová: 3D spheroid culture for in vitro testing of nanoparticles 35 3.2 Topic: METROLOGY 37 3.2.1 Katrien Boonen: The potential of dendrochemistry and dendroecology in pollution research 37 3.2.2 Ivan Lopez Carasco: Development of immobilization protocols for Tro6 and Tro4 aptamers to be used in electrochemical biosensor 38 3.2.3 Jacub Hoskovec: Functionalized electrospun materials for selectvie capture of selected gases 39 3.2.4 Dominic Pilnaj: Applications of gas sensors for air-quality monitoring and identification of volatile organic compounds by GC-HRMS 39 3.2.5 Michaela Průšová: Prostat, Glioblastoma and Mammary carcinoma cells derived exosomes: Their isolation, characterization and loading with doxorubicin 40 3.2.6 Kateřina Přibylová: Preparation of nanostructured surfaces for CO2 Detection, Capture and Utilization 41 3.2.7 Michal Syrový: Chemical modification of PAN – based nanofibrous membranes prepared by electrospinning and their properties for CO2 capture potential 42 3.3 Topic: GEOLOGICAL/MATERIALS 43 3.3.1 Sabine Apelt: Using biomimicry to design anti-ice surfaces for air-water heat pumps 43 3.3.2 Jan Dočkal: Molecular dynamics of interfacial solution structure of alkali-halide electrolytes at graphens electrodes 47 3.3.3 Tereza Dušková: Metal complexes with polyfluorinated NHCs 48 3.3.4 Kristína Fiantoková: Obtaining of the active mass from the spent Li-Ion batteries 48 3.3.5 Stephanie Ihmann: Engineering of bio-based Building and Construction Materials 49 3.3.6 Sara Jalali: Degradable bone substitute materials with load-bearing properties - Fiber-strengthened silica 50 3.3.7 Pavel Kaule: Preparation of heteroborane derivatives for thin film deposition by the covalent bond formation 53 3.3.8 M. Kozakovic: The effect of primary and secondary flows on the homogenization process in a vertical bladed mixer 53 3.3.9 Pavlína Matysová: Molecular Simulation of Salt Hydrates 54 3.3.10 Viktorie Neubertová: Surface functionalization of Ti3C2T MXene for MRI contrast agent 55 3.3.11 Robert Ato Newton: Fuel characteristics of Miscanthus x giganteus biomass produced at the marginal and slightly contaminated by trace elements soils 55 3.3.12 Martin Otto: Bioresorbable Fe-based alloys processed via laser powder bed fusion 56 3.3.13 Petr Panuška: A millifluidic chip for cultivation of fish embryos and toxicity testing fabricated by 3D printing technology 59 3.3.14 David Poustka: Unlocking mass production of photocrosslinked chitosan nanofibers 60 3.3.15 Eliška Rezlerová: Adsorption and Diffusion of Short Hydrocarbons and Carbon Dioxide in Shale Organic Matter: Insights from Molecular Simulations 60 3.3.16 Stefan Weitz: Investigating the material hardness of mollusks shells in dry and wet states by microindentation 6

    An Investigation into an All Polymer Knee Joint Replacement

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    My thesis describes a series of tests aimed at investigating the suitability of polyetheretherketone (PEEK), carbon fibre reinforced polyetheretherketone (CFR-PEEK), polyethylene and acetal in an all polymer, metal free total knee replacement. Central to this study was the investigation of the wear performance of these polymers as bearing materials under two different loading conditions and in comparison, to contemporary metal on polyethylene (MoP) bearings. The concept of an all polymer total knee replacement (TKR) is intended to realise physiological stress distribution within periprosthetic bone, reduce stress shielding and bone loss and eliminate biological activity to particulate metal alloy. The hypothesis was that an all polymer bearing will generate reduced or similar amounts of wear when compared with the traditional metal-on-plastic bearing and may provide an alternate metal-free method of replacement. Following unidirectional pin on plate testing, wear of the different bearing combinations was assessed using gravimetric analysis, digital photography, surface profilometry and scanning electron microscopy (SEM). Characterization of wear particles generated from these bearing combinations was conducted following digestion of the particle containing lubricant fluid using an acid digestion method with isolated particles subjected to SEM analysis and an automated image analysis sequence. Subsequently, the inflammatory response of depyrogenated, endotoxin free wear particles retrieved from the pin-on-plate test was cultured with monocytes and cytokine production (TNF-α, IL-1β and Il-6) quantified as measured using ELISA. The key findings from my thesis were that using a pin on plate test setup designed to simulate a simplified knee couple, PEEK pins articulated against moderately cross-linked polyethylene plate exhibited comparable wear loss, a similar wear quantity, morphology and inflammatory potential to the contemporary metal on polyethylene articulations. CFR-PEEK was found unsuitable as a bearing surface in an all polymer TKR. Based on this, my hypothesis can be accepted as it may be possible to replace CoCr in TKR. However, before translation to clinical use, exhaustive appraisal of new bearing components is necessary to confer confidence in their appropriateness and safety. An all polymeric PEEK-on-a highly crosslinked polyethylene (XLPE) bearing may be a promising alternative to MoP in total knee arthroplasty

    Surface modification of zirconia-based bioceramics for orthopedic and dental applications

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    Debido a sus excelentes propiedades mecánicas y una excelente biocompatibilidad, el uso de las cerámicas de base de circona en aplicaciones dentales y ortopédicas ha crecido rápidamente durante las últimas décadas. Sin embargo, tanto la alúmina como la circona son bioinertes, lo cual dificulta su implantación en contacto directo con el hueso. Además, las infecciones siguen siendo una de las principales causas de fallo de implantes. Para resolver ambos problemas, se requiere un mejor diseño de la superficie: en particular, una topografía adecuada puede promover la osteointegración y limitar la adhesión bacteriana. Por otro lado, la fiabilidad a largo plazo es un asunto crítico para los implantes estructurales, y las cerámicas que contienen circona requieren una atención especial. Como para otras cerámicas, las alteraciones superficiales pueden comprometer sus propiedades mecánicas. Además, la transformación de fase de tetragonal a monoclínica, que les proporciona una tenacidad excepcional, puede ocurrir espontáneamente en presencia de agua, lo cual puede afectar las propiedades del material. La cinética de este fenómeno, conocido como envejecimiento hidrotérmico, es muy sensible a los cambios de procesamiento. Por lo tanto, cualquier modificación de la superficie debe ir acompañada de una evaluación de su impacto en la fiabilidad de los implantes. Basado en estas observaciones, el objetivo de esta tesis fue desarrollar procesos para modificar la superficie de los implantes a base de circona, en particular la topografía, sin comprometer sus propiedades mecánicas y estabilidad hidrotérmica. El esfuerzo de investigación se centró en dos materiales: la circona estabilizada con itria (3Y-TZP), que se utiliza cada vez más para aplicaciones dentales (por ejemplo: coronas, implantes), y la alúmina reforzada con circona (ZTA), que es el estándar actual en ortopedia para la fabricación de componentes cerámicos estructurales. Por lo tanto, este trabajo se puede dividir en dos partes principales. En la primera parte, se llevó a cabo un amplio estudio del ataque de la circona con ácido fluorhídrico (HF). Se demostró que ajustando el tiempo de decapado es posible controlar la rugosidad y la dimensión fractal de la superficie. Además, los resultados indican condiciones adecuadas para incrementar la rugosidad de forma rápida y uniforme, sin comprometer su resistencia mecánica ni tampoco su resistencia al envejecimiento. Basándose en estos hallazgos, se obtuvieron muestras con gradientes de rugosidad mediante inmersión con una velocidad controlada en una solución de ataque. Gracias a este método, que reduce drásticamente los esfuerzos y recursos necesarios para estudiar las interacciones célula-superficie, se realizó un análisis rápido de la influencia de la micro- y nano-topografía inducida por HF en las células madre mesenquimales. Se determinaron correlaciones entre parámetros de rugosidad y morfología celular, destacando la importancia de la optimización de la topografía a múltiples escalas para inducir la respuesta celular deseada. En la segunda parte, una estrategia integrada fue desarrollada para proporcionar propiedades antibacterianas y osteointegrativas a las superficies de ZTA La micro-topografía se controló mediante moldeo por inyección. Mientras tanto, un nuevo procedimiento que implica la disolución selectiva de la circona por HF (ataque selectivo) se utilizó para producir nano-rugosidad y una nanoporosidad superficial interconectada. La utilización potencial de la porosidad para la liberación de antibióticos fue demostrada, y se evidenció que la encapsulación liposomal puede aumentar la cantidad de fármaco cargada. Además, se demostró que el impacto del ataque selectivo sobre las propiedades mecánicas y la estabilidad hidrotermal era limitado. Por lo tanto, la combinación del moldeo por inyección y del ataque selectivo parece prometedora para la fabricación de componentes de ZTA implantables en contacto directo con el huesoDue to their outstanding mechanical properties and excellent biocompatibility, the use of zirconia-based ceramics in dental and orthopedic applications has grown rapidly over the last decades. However, both alumina and zirconia are bioinert, which hampers their implantation in direct contact with bone. Furthermore, infections remain one of the leading causes of implant failure. To address both issues, an improved surface design is required: in particular, an adequate topography can promote osseointegration and limit bacterial adhesion. On the other hand, long-term reliability is a major concern for load-bearing implants, and zirconia-containing ceramics require special attention. As for other ceramics, surface alterations can impair their mechanical properties. Besides, the tetragonal to monoclinic phase transformation, which accounts for their exceptional toughness, can occur spontaneously in the presence of water, potentially deteriorating the material properties. The kinetics of this phenomenon, known as hydrothermal ageing, are highly sensitive to processing changes. Any surface modification of zirconia-containing ceramics should thus be accompanied by a careful assessment of its impact on implant reliability. Based on these observations, the objective of this thesis was to develop processes to modify the surface of zirconia-based implants, in particular the topography, without compromising their mechanical properties and hydrothermal stability. The research effort focused on two materials of particular interest: yttria-stabilized zirconia (3Y-TZP), which is increasingly used for prosthodontic applications (e.g., crowns, implants), and zirconia toughened alumina (ZTA), which is the current gold Standard in orthopedics for the fabrication of load-bearing ceramic components. Accordingly, this work can be divided into two main parts. In the first part, an extensive study of the hydrofluoric acid (HF) etching of zirconia was carried out. It was shown that monitoring etching time allows controlling the roughness and fractal dimension of the surface. Furthermore, the results indicated suitable processing conditions for a fast and uniform roughening of zirconia components, without compromising substantially their strength and ageing resistance. Based on these findings, zirconia samples with roughness gradients were obtained by immersing specimens into an etching solution with a controlled speed. Thanks to this method, which drastically reduces the efforts and resources necessary to study cell-surface interactions, a rapid screening of the influence of HF-induced micro- and nano-topography on mesenchymal stem cell morphology was conducted. Correlations between roughness parameters and cell morphology were evidenced, highlighting the importance of multiscale optimization of topography to induce the desired cell response. In the second part, an integrated strategy was developed to provide both osseointegrative and antibacterial properties to ZTA surfaces. The micro-topography was controlled by injection molding. Meanwhile a novel process involving the selective dissolution of zirconia by HF (selective etching) was used to produce nano-roughness and interconnected Surface nanoporosity. Potential utilization of the porosity for delivery of antibiotic molecules was demonstrated, and it was shown that liposomal encapsulation could improve drug loading. Furthermore, the impact of selective etching on mechanical properties and hydrothermal stability was shown to be limited. The combination of injection molding and selective etching thus appears promising for fabricating a new generation of ZTA components implantable in direct contact with bone

    The Application of Melatonin and Platelet-Rich Plasma in the Development of a Bioactive Calcium Aluminate Bone Regenerative Scaffold

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    Over 500,000 bone graft procedures are conducted annually within the United States. Autografts contribute to donor site complications and disease transmission with allografts has been described. Many ceramics are only osteoconductive and are brittle, limiting their clinical use. Thus, the objective of this study was to create a bone substitute with osteoinductive properties similar to natural bone using the ceramic biomaterial calcium aluminate (CA). Calcium aluminate materials are durable and remain moldable for an extended period of time at room temperature. Further, the surfaces of CA scaffolds can be modified with biological agents through simple chemical means to locally deliver agents directly to sites of injury. In order to enhance local bone regenerating characteristics of CA scaffolds, melatonin and platelet-rich plasma (PRP) were utilized for their known osteoinductive properties. Platelet-rich plasma enhances soft and hard tissue formation primarily through growth factor-mediated signaling pathways. Melatonin augments osteoblast differentiation and inhibits osteoclast-mediated bone resorption through receptor-dependent signaling and free radical scavenging activity, respectively. Thus, it was hypothesized that melatonin and/or PRP would provide osteoinductive properties to CA scaffolds to promote bone regeneration in a rodent model of critical-size calvaria defects. Modified CA scaffolds (CA-Mel) were produced by immobilizing melatonin to the CA surface through a covalent linkage. The biocompatibility of unmodified and modified CA scaffolds was initially tested in vitro and indicated that modified surfaces had a preference for the adhesion and proliferation of normal human osteoblasts versus NIH 3T3 fibroblasts. Moreover, the immobilization of melatonin to the CA surface may delay the differentiation of human adult mesenchymal stem cells (hAMSCs) and may have facilitated their migration across the CA surface. Two-month-old ovariectomized rats were randomized into implant groups receiving unmodified or modified scaffolds in the absence (CA and CA-Mel) or presence of PRP (CA+PRP and CA-Mel+PRP). Histological sections confirmed that both CA scaffold types were well-tolerated and provided evidence of tissue infiltration and scaffold biodegradation over time. Bone regeneration in animals was assessed by fluorochrome labeling at three and six months. While there was a lack of synergism between melatonin and PRP in the CA-Mel+PRP group, animals implanted with CA-Mel showed the greatest intensity and abundance of bone remodeling at both time points compared to all other groups. Radiographic data indicated a significant increase in the density of newly formed bone over time in all groups. The absence of a detectable decrease in density suggests that the modest biodegradation of CA scaffolds is balanced with processes of bone formation. Finally, both unmodified and modified CA scaffolds continued to provide a supportive surface for bone formation out to six months. Overall, results from this study suggest that CA scaffolds modified with melatonin may enhance bone remodeling activity in calvarial defects through hAMSC differentiation and recruitment and by preferentially supporting the viability and function of mature osteoblasts. This novel bioactive ceramic scaffold has the potential to change the dogma of bone grafting in fields like dentistry and reconstructive surgery. Continued optimization of this therapy is warranted and the attachment of other osteoinductive biomolecules is being considered

    DESIGN STRATEGIES AND ADDITIVE MANUFACTURING OF 3D CUSTOMIZED SCAFFOLDS WITH OPTIMIZED PROPERTIES FOR CRANIOFACIAL TISSUE ENGINEERING

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    3D customized scaffolds for craniofacial tissue engineering were designed using advanced strategies and technologies. Specifically, reverse engineering, additive manufacturing, material selection, experimental and theoretical analyses were properly integrated. The focus was on: i) design strategies of 3D customized nanocomposite scaffolds for hard tissue regeneration; ii) an engineered design of 3D additive manufactured nanocomposite scaffolds with optimized properties; iii) an approach toward the design of 3D customized scaffolds for large cranial defects

    Development of a Mechanically-Stimulated Tissue-Specific Extracellular Matrix Coated Scaffold for Tendon/Bone Interface Engineering

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    The enthesis is a complex anatomical and functional interface between tendon and bone. Once injured, this site does not readily heal and is repaired with limited success. To aid in repair of the enthesis a commercially available scaffold was chosen, from 3 candidate biomaterials, with fibroblast and osteoblast deposited extracellular matrix (ECM) to create a tendon and bone region, respectively, on the scaffold. To further enhance the ECM deposition, the seeded scaffold was mechanically stimulated in a custom built bioreactor for 35 days. The scaffolds were then evaluated by looking at tissue specific gene activation of mesenchymal stem cells (MSC)s due to the deposited ECM.Out of the three materials, non-degradable polyester fabric (PET), degradable polylactic acid (PLA) fabric, and biologic acellular dermal matrix (ACDM), the PLA fabric had the best combination of ECM deposition and mechanical strength for the project. After selecting a scaffold, we determined the parameters for co-culture medium, with respect to fibroblast and osteoblast mineralization. It was determined that standard growth medium, alpha-MEM + 10% fetal bovine serum + 1000 U/mL penicillin, 1000 μg/mL streptomycin, 2.5 μg/mL amphotericin-B + 3 mM beta-glycerophosphate + 25 μg/mL of ascorbic acid provided low fibroblast mineralization while still allowing for osteoblast mineralization. Fluorescence imaging demonstrated that a co-cultured scaffold could be seeded to produce two distinct tissue specific regions. The transition zone produced had values for collagen and glycosaminoglycan (GAG) deposition between that of the two tissue specific regions. Lastly after mechanical conditioning, stimulating the entire scaffold produced an increase in cell number, and the ratio of collagen to GAG in ECM compared to static culture. When the MSCs were exposed to the tissue specific regions, entirely stretched ECM caused an increase in collagen and tendon-specific GAG gene activation and a decrease in mineralization gene activation compared to tissue culture plastic. Cartilage specific markers were unchanged.In conclusion, a suitable commercially available scaffold was identified. The scaffold was seeded so a tendon specific and bone specific regions were distributed on the scaffold. Mechanically conditioning the scaffolds in a bioreactor increased the activation of tissue specific genes for tendon and bone compared to stem cells seeded on tissue culture plastic. Future work includes a functional scaffold testing in an in vivo tendon-to-bone animal model
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