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The outcomes revealed that the rate of endothelialization of the nanocomposite scaffold after 7 days of in vitro cell culture was 1.5 times and the rate of degradation of the nanocomposite film was 2 times after 8 weeks of immersion scaffolds in PBS compared to the polyurethane scaffolds. In addition, the nanocomposite scaffold possessed good mechanical properties. Selleckchem MLN2238 Despite its high modulus, it was flexible with a 500% elongation at break.The treatment of infectious or potentially infective bone defects remains a major problem in clinical practice. Silver has the ability to potentiate antibiotics against resistant bacterial strains. In order to reduce the risk of long-term infections, it is necessary for the biomaterial scaffold to release Ag+ in a controlled manner during the entire healing process. In this study, given the antimicrobial characteristics of nanosized Ag (NSAg), we synthesized β-tricalcium phosphate (β-TCP) doped with 5 and 10 wt% NSAg (5 wt% NSAgTCP and 10 wt% NSAgTCP, respectively). The NSAgTCP composites exhibited similar macroporous structures to pure β-TCP. The NSAgTCP samples were examined by scanning electron microscopy at 10,000-times magnification, which revealed that silver was still present at the nanometer scale. X-ray diffraction revealed that silver does not change the crystalline properties of β-TCP. In addition, we observed that the mechanical strength of NSAgTCP increased with increasing amounts of added Ag. The antibacterial, physical, and chemical properties of NSAgTCP were investigated in vitro. We found that NSAgTCP is effective at inhibiting the growth of Staphylococcus aureus and Escherichia coli and is not cytotoxic to human bone marrow mesenchymal stem cells. Moreover, it does not hinder liver or kidney function when tested in vivo. As the bioceramic degrades, Ag ions are slowly released and new bone is formed. No significant cytotoxic effects were observed even when 10 wt% NSAgTCP was used. NSAgTCP has the ability to simultaneously repair bone defects and act as an anti-infective agent; hence, we expect that this material, with its good bone-repairing and anti-infective properties, will find wide spread use as a novel bone substitute.Cell infiltration and proliferation are prerequisites for tissue regeneration and repair. The aim of the present study was to evaluate the motility and function of vascular smooth muscle cells (SMCs) in a silk-based small-caliber artificial blood vessel (SFTS) following implantation to replace the common carotid artery in rabbits. Hematoxylin and eosin (HE) staining showed a number of SMCs clearly distributed in the scaffold at 1 month, which gradually increased up to 80-90% of autologous blood vessels at 3 months and was 100% at 12 months. Smooth muscle myosin heavy chain (SM-MHC) and α-smooth muscle actin (α-SMA) are specific markers of SMCs. Real-time PCR results showed that the gene expression level of α-SMA in SFTSs was significantly down-regulated within 6 months, except in the early stage of implantation. The relative expression level of α-SMA at 12 months was five times higher than that at 3 months, indicating that SMCs phenotype transformed from synthetic to contractile. The SM-MHC+ and α-SMA+ SMCs were disorderly distributed in the scaffolds at 1 month, but became ordered along the circumference 6 months after grafting as shown by immunohistochemistry. Results indicated that the bionic SFTSs were able to induce in situ angiogenesis in defects.Cerium oxide nanoparticles (nanoceria) have recyclable antioxidative activity. It has numerous potential applications in biomedical engineering, such as mitigating damage from burns, radiation, and bacterial infection. This mitigating activity is analogous to that property of metabolic enzymes such as superoxide dismutase (SOD) and catalase - scavengers of reactive oxygen species (ROS). Therefore, nanoceria can protect cells from environmental oxidative stress. This therapeutic effect prompted studies of nanoceria and metabolic enzymes as a combination therapy. The activity and structure of SOD, catalase, and lysozyme were examined in the presence of nanoceria. A complementary relationship between SOD and nanoceria motivated the present work, in which we explored a method for simultaneous delivery of SOD and nanoceria. The biocompatibility and tunable degradation of poly(lactic-co-glycolic acid) (PLGA) made it a candidate material for encapsulating both nanoceria and SOD. Cellular uptake studies were conducted along with a cytotoxicity assay. The antioxidative properties of PLGA-nanoceria-SOD particles were verified by adding H2O2 to cell culture and imaging with fluorescent markers of oxidative stress. Our results suggest that PLGA is a suitable encapsulating carrier for simultaneous delivering nanoceria and SOD together, and that this combination effectively reduces oxidative stress in vitro.Rapid, on-site detection of emerging pollutants is critical for monitoring health threats and the environment, especially if performed through autonomous systems. In this paper, we report on a new design of a complete electrochemical system whose working (WE), auxiliary (AE) and reference (RE) electrodes were obtained on a pen (PEN Sensor) made with graphitepolyurethane (GPUE). Working electrodes were decorated with spherical, ca. 200 nm silver nanoparticles (AgNPs) reduced on graphite using the polyol method. Differential pulse voltammetry (DPV) was used to detect bisphenol-A (BPA) in a linear range from 2.5 to 15 μmol L-1 with detection limit of 0.24 μmol L-1. The PEN Sensor could also detect bisphenol-A in tap and river water samples, with satisfactory reproducibility and repeatability, while common interferents did not affect electrooxidation of bisphenol-A. The high sensitivity and rapid detection are suitable for real-time analysis and in loco monitoring of emerging pollutants. With their robustness and versatility, PEN Sensors such as those fabricated here may be integrated into futuristic smart robotic systems.Fused Deposition Modelling (FDM) technique has been widely utilized in fabrication of 3D porous scaffolds for tissue engineering (TE) applications. Surprisingly, although there are many publications devoted to the architectural features of the 3D scaffolds fabricated by the FDM, none of them give us evident information about the impact of the diameter of the fibres on material properties. Therefore, the aim of this study was to investigate, for the first time, the effect of the diameter of 3D-printed PCL fibres on variations in their microstructure and resulting mechanical behaviour. The fibres made of poly(ε-caprolactone) (PCL) were extruded through commonly used types of nozzles (inner diameter ranging from 0.18 mm to 1.07 mm) by means of FDM technique. Static tensile test and atomic force microscopy working in force spectroscopy mode revealed strong decrease in the Young's modulus and yield strength with increasing fibre diameter in the investigated range. To explain this phenomenon, we conducted differential scanning calorimetry, wide-angle X-ray-scattering, Fourier-transform infrared spectroscopy, infrared and polarized light microscopy imaging.

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