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new clues for further exploring the possible mechanism underlying osteoinduction by CaP materials.Collagen is the most abundant component of the extracellular matrix (ECM), therefore it represents an ideal biomaterial for the culture of a variety of cell types. Recently, collagen-based scaffolds have shown promise as 3D culture platforms for breast cancer-based research. Two-dimensional (2D) in vitro culture models, while useful for gaining preliminary insights, are ultimately flawed as they do not adequately replicate the tumour microenvironment. As a result, they do not facilitate proper 3D cell-cell/cell-matrix interactions and often an exaggerated response to therapeutic agents occurs. The ECM plays a crucial role in the development and spread of cancer. Alterations within the ECM have a significant impact on the pathogenesis of cancer, the initiation of metastasis and ultimate progression of the disease. 3D in vitro culture models that aim to replicate the tumour microenvironment have the potential to offer a new frontier for cancer research with cell growth, morphology and genetic properties that more closely match in vivo cancers. While initial 3D in vitro culture models used in breast cancer research consisted of simple hydrogel platforms, recent advances in biofabrication techniques, including freeze-drying, electrospinning and 3D bioprinting, have enabled the fabrication of biomimetic collagen-based platforms that more closely replicate the breast cancer ECM. This review highlights the current application of collagen-based scaffolds as 3D in vitro culture models for breast cancer research, specifically for adherence-based scaffolds (i.e. matrix-assisted). Finally, the future perspectives of 3D in vitro breast cancer models and their potential to lead to an improved understanding of breast cancer diagnosis and treatment are discussed.Recently, just taking endothelialization of stent as an interventional treatment of aneurysms is unsatisfactory. This treatment also has impacts the occlusion rate of the aneurysm. In accordance with that, the authors aims to construct a novel biological factor-coated stent with dual biological effects of anticoagulation and endothelialization for the improvement of the occlusion rate of aneurysms and reduction of the risk for treatment of aneurysm with intravascular interventional therapy. The Ni-Ti alloy sheets loaded with VEGF and anti-CD34 antibody were put into use for stimulating the construction of the biological factor-coated stents, for the Ni-Ti alloy sheets could help improve the proliferation of endothelial cell (EC), recognize effectively and adhere to endothelial progenitor cell (EPC). Blood compatibility characterization methods (water contact angle, platelet activation test, clotting time evaluation and protein adsorption test) were applied for study the influence of the interaction between the Ni-Ti alloy sheets and blood. Cell experiments (HUVEC proliferation experiment, migration experiment and EPC capture experiment) were resorted to investigate the ability of the sheets to promote the proliferation of HUVEC and to capture EPCs. With the mature of the construction technology, the Enterprise stent with the biological factors were optimized accordingly, the biological function of that were verified by cell experiments. Studies showed that Ni-Ti alloy sheets and enterprise stents can successfully load with VEGF and anti-CD34 antibody. The below achievements can be realized including a better blood compatibility and effects of the constructed sheets and enterprise stents on promoting HUVEC proliferation and adhesion of EPC. It was meaningful of conversion to clinical application to improve the cure rate of the aneurysm and the safety of the intravascular treatment.Various coatings have been developed for biodegradable Mg alloys to control the degradation speed and to improve the bone conductivity. In this study, hydroxyapatite (HAp) coatings were formed on pure Mg, Mg-0.8mass% Ca (MgCa), Mg-4mass% Y-3mass% rare earth (RE) (WE43), Mg-3mass% RE-1mass% Y (EW31) and Mg-4mass% RE (RE4) alloy rods with a chemical solution deposition method. The HAp-coated and uncoated Mg/Mg alloy rods were implanted in the femurs of rats for 3-6 months, and the corrosion suppression and bone formation abilities of the HAp coating were examined using a scanning electron microscope. The corrosion rate of WE43 was suppressed by 1/3 with the HAp coating for 6 months, and the corrosion product showed very slow dissolution. The effect of the HAp coating for pure Mg and MgCa disappeared in 1-2 months with the thinning of the rods accompanying with the obvious dissolution of the corrosion products. The effect of the HAp coating for EW31 and RE4 was not stable due to the expansion and collapse of the corrosion products. The bone formation was enhanced on the HAp layers. Eventually, the HAp coating basically suppressed the corrosion initiation and corrosion progress of Mg substrates. The magnitude of the suppression effect depended mainly on the chemical and physical stability of the corrosion products.Strontium loaded titania nanotube arrays (NTSr), as well as titania nanotube arrays (NT), have been regarded as effective coatings to promote bone regeneration on titanium implants, but an understanding of the full extent of early processes affected by such surface modifications is absent. To address this limitation, we performed RNA sequencing (RNA-seq) of Sprague-Dawley rat bone marrow mesenchymal stem cells (rBMMSCs) cultured on unmodified titanium sheets (Con), NT and NTSr specimens. By pairwise comparisons we found that NT and NTSr shared a majority of differentially expressed genes. The Gene Ontology (GO) analysis revealed that NT and NTSr up-regulated a bunch of genes that are annotated to the cytoskeleton. The results were supported by immunofluorescent, transmission electron microscopy (TEM) and western blotting assays. By inhibiting the cytoskeleton through pharmacological agents, the activities of alkaline phosphatase (ALP) on NT and NTSr were also suppressed. Informed by these results, we concluded that NT and NTSr specimens reorganized the cytoskeleton of cultured cells that may play a crucial role in osteogenic lineage commitment.The concept of providing tissue engineering scaffolds with natural physical properties and minimal immunogenicity has not been systematically approached for the lungs yet. Here, the rat acellular lung tissue (ALT) was cross-linked to provide either EDC/NHS cross-linked tissue (EDC/NHS-CLT) or tannic acid cross-linked tissue (TA-CLT). Young's modulus revealed that EDC/NHS-CLT had mechanical properties similar to the native lung and culture of lung mesenchymal cells showed a higher potential of cell proliferation on EDC/NHS-CLT versus TA-CLT and ALT. The in vitro immunogenicity tests showed a strong induction of T-cell proliferation by TA-CLT and an attenuated macrophage induction by TA-CLT. Processed rat lungs were implanted xenogenically into the mouse peritoneal cavity and the host-implant interactions showed that tannic acid is not released from TA-CLT in a physiologically effective dose. The profile of peritoneal fluid proinflammatory (TNFα, IL-1β, IL-12p70 and IL-17) and anti-inflammatory (IL-10 and TGFβ1) cytokines, and CD3+ T-lymphocytes and CD11b+ macrophages revealed that apart from induction of high levels of IL-17 during the first week and IL-10 during the second to third weeks after implantation by TA-CLT, other indicators of immune reactions to cross-linked tissues were not significantly different from ALT. Also, a high fibrotic reaction to TA-CLT was observed on the weeks 2-3, but alveolar structures were preserved in EDC/NHS-CLT. Our findings show that by controlled EDC/NHS cross-linking, an acellular lung scaffold could be provided with mechanical properties similar to native lung, which promotes mesenchymal lung cells proliferation and does not stimulate recipient's immune system more than a non-cross-linked tissue.Airway respiratory epithelium forms a physical barrier through intercellular tight junctions, which prevents debris from passing through to the internal environment while ciliated epithelial cells expel particulate-trapping mucus up the airway. selleck screening library Polymeric solutions to loss of airway structure and integrity have been unable to fully restore functional epithelium. We hypothesised that plasma treatment of polymers would permit adsorption of α-helical peptides and that this would promote functional differentiation of airway epithelial cells. Five candidate plasma compositions are compared; Air, N2, H2, H2N2 and AirN2. X-ray photoelectron spectroscopy shows changes in at% N and C 1s peaks after plasma treatment while electron microscopy indicates successful adsorption of hydrogelating self-assembling fibres (hSAF) on all samples. Subsequently, adsorbed hSAFs support human nasal epithelial cell attachment and proliferation and induce differentiation at an air-liquid interface. Transepithelial measurements show that the cells form tight junctions and produce cilia beating at the normal expected frequency of 10-11 Hz after 28 days in culture. The synthetic peptide system described in this study offers potential superiority as an epithelial regeneration substrate over present "gold-standard" materials, such as collagen, as they are controllable and can be chemically functionalised to support a variety of in vivo environments. Using the hSAF peptides described here in combination with plasma-treated polymeric surfaces could offer a way of improving the functionality and integration of implantable polymers for aerodigestive tract reconstruction and regeneration.The most pressing need in cartilage tissue engineering (CTE) is the creation of a biomaterial capable to tailor the complex extracellular matrix of the tissue. Despite the standardized used of polycaprolactone (PCL) for osteochondral scaffolds, the pronounced stiffness mismatch between PCL scaffold and the tissue it replaces remarks the biomechanical incompatibility as main limitation. To overcome it, the present work was focused in the design and analysis of several geometries and pore sizes and how they affect cell adhesion and proliferation of infrapatellar fat pad-derived mesenchymal stem cells (IPFP-MSCs) loaded in biofabricated 3D thermoplastic scaffolds. A novel biomaterial for CTE, the 1,4-butanediol thermoplastic polyurethane (b-TPUe) together PCL were studied to compare their mechanical properties. Three different geometrical patterns were included hexagonal (H), square (S), and, triangular (T); each one was printed with three different pore sizes (PS) 1, 1.5 and 2 mm. Results showed differences in cell adhesion, cell proliferation and mechanical properties depending on the geometry, porosity and type of biomaterial used. Finally, the microstructure of the two optimal geometries (T1.5 and T2) was deeply analyzed using multiaxial mechanical tests, with and without perimeters, μCT for microstructure analysis, DNA quantification and degradation assays. In conclusion, our results evidenced that IPFP-MSCs-loaded b-TPUe scaffolds had higher similarity with cartilage mechanics and T1.5 was the best adapted morphology for CTE.

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