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Background: Valvular heart diseases (VHDs) have become prevalent in populations due to aging. Application of different biomaterials for cardiac valve regeneration and repair holds a great promise for treatment of VHD. Aortic valve replacement using tissue-engineered xenografts is a considered approach, and the pericardium of different species such as porcine and bovine has been studied over the last few years. It has been suggested that the animal origin can affect the outcomes of replacement. Methods: So, herein, we at first decellularized and characterized the camel pericardium (dCP), then characterized dCP with H&E staining, in vitro and in vivo biocompatibility and mechanical tests and compared it with decellularized bovine pericardium (dBP), to describe the potency of dCP as a new xenograft and bio scaffold. Results: The histological assays indicated less decluttering and extracellular matrix damage in dCP after decellularization compared to the dBP also dCP had higher Young Modulus (105.11), and yield stress (1.57 ± 0.45). We observed more blood vessels and also less inflammatory cells in the dCP sections after implantation. Conclusions: In conclusion, the results of this study showed that the dCP has good capabilities not only for use in VHD treatment but also for other applications in tissue engineering and regenerative medicine. [ABSTRACT FROM AUTHOR]

The research aimed to evaluate the mechanical behaviour, hybridisation and osteoblast activities of novel baghdadite/PCL-graphene nanocomposite scaffold. The mechanical behaviour was examined via measuring the compressive strength and Young's module, the hybridisation was evaluated by Fourier transform infrared spectroscopy, Raman spectroscopy, and Brunauer Emmet Teller, and the osteoblast activities were assessed via MG-63 osteoblast cells. The results rendered PCL as a significant factor to enhance the mechanical strength of ceramic scaffolds. Due to the existence of σ and π covalent bonds in its structure, hydrophilicity and biocompatibility, graphene could be applied in scaffolds' chemical compound to greatly enhance their mechanical and biological behaviours. This scaffold indicated compressive strength and Young's module higher than 2 MPa and 0.05 GPa. Regarding cell behaviours, MG-63 osteoblast cells spread and attached well on the scaffolds confirming the viability, cytotoxicity, excellent cell attachment and proliferation. The results indicated that this scaffold possesses outstanding potential as a temporary substrate for bone tissue engineering. [ABSTRACT FROM AUTHOR]

The aim of the present research was to find out the in vitro biological behaviour by evaluating the bioactivity of scaffolds for bone tissue engineering and to examine the mechanism of baghdadite and apatite formation. For this purpose, baghdadite scaffolds with polycaprolactone and graphene nanocomposite coatings were fabricated using polymeric sponge and dip-coating methods. Results showed that regarding baghdadite formation mechanism, gittinsite phase can be converted into baghdadite phase by enhancing temperature up to 1350°C and helping Zr4+ and Ca2+. The deposit of Ca–P coatings on the surface and in the pores of the scaffolds verified the improvement of the bioactivity. Graphene in scaffold composition can affect apatite deposit formation and promise bioactivity due to its high hydrophilicity, existence of nanoparticles and great π bonds in its structure. In brief, baghdadite scaffolds with polycaprolactone and graphene nanocomposite coatings can be promising outstanding candidates for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Conductive materials are required for sensing and actuation purposes in microfluidic devices. Electrical and mechanical properties of aligned CNTs/PDMS nanocomposites fabricated in AC and quasi-AC electric fields were measured. Field emission scanning electron microscope and elemental mapping were used to evaluate the microstructural properties of fabricated specimens. Results showed that nanocomposite properties were dependent on CNT concentration. A homogenized and nonagglomerated composite was obtained using a quasi-AC electric field with the voltage of 1075 V zero to peak at a frequency of 100 Hz and current of 35 milliamps when applied to suspension for 2 hours at 80 °C. The aligned nanocomposite with 1 wt% of CNT exhibited an electrical conductivity, Young's modulus, and tensile strength of 10-6 S/cm, 7.23 MPa, and 1.02 MPa, respectively. [ABSTRACT FROM AUTHOR]

Over the past two decades calcium silicate (Ca–Si) based ceramics have been introduced as bioactive materials for bone tissue engineering applications and repairing bone defects. Recently, it is reported that zirconium modified calcium‐silicate‐based (Ca3ZrSi2O9, Baghdadite) ceramics stimulate cell proliferation and osteogenic differentiation of osteoblasts. The aim of this work was preparation, characterization, and evaluation of biological properties of Baghdadite in the nanoparticles form. These nanoparticles were synthesized by sol‐gel method and were annealed at 1150°C. Fabricated nanoparticles were investigated using XRD, FE‐SEM, EDX, and MTT in vitro, then implanted to the rabbit tibia as a bone animal model. The characterization results showed that nanoparticles with expected composition were successfully synthesized using sol‐gel method. According to MTT result, these nanoparticles were nontoxic. In addition, the proliferation of bone marrow derived mesenchymal stem cells was increased after 96 hours of culturing in the presence of nanoparticles compared to the control. Histopathological results also demonstrated that the defected bone was completely regenerated when implanted with nanoparticles after 6 weeks. Taking together, according to the results, Ca3ZrSi2O9 nanoparticles as a bioceramic with excellent biological properties can be applied for improvement of bone lesions healing process in the orthopedic and dental application. [ABSTRACT FROM AUTHOR]

In this study, a ceramic‐coated nanofibrous scaffold has been fabricated to biomimic the microstructure of natural extracellular matrix and the stiffening inorganic compartment of bone. Poly‐l‐lactic acid (PLLA) nanofibers were electrospun and exposed to oxygen plasma to induce hydrophilicity and promote ceramic adsorption. Hardystonite (HS), which possesses superior osteoinduction potential over hydroxyapatite, was coated on plasma‐treated PLLA nanofibers by drenching the nanofibers in HS suspension. Pure and composite PLLA‐based scaffolds were characterized in terms of physical and biological properties. In vitro cultivation of adipose‐derived mesenchymal stem cells (AMSCs) on the scaffolds displayed that the composite scaffold is able to further support cell attachment and proliferation. In case of osteogenic differentiation of AMSCs, HS coating significantly increased the synthesis and activity of alkaline phosphate over 21 days period. In addition, the composite scaffold showed improved mineralization. The expression level of osteonectin and osteocalcin genes was significantly enhanced by HS coating of nanofibers. The biological improvement of PLLA nanofibrous matrix in the presence of HS nanoparticles could either be attributed to the release and stimulatory effect of constituent ions of HS or to the modification of chemico‐physical properties of the resultant ceramic by silicon and zinc present in HS. [ABSTRACT FROM AUTHOR]

ABSTRACT Considerable efforts have been devoted toward the development of electrospun scaffolds based on poly(ε-caprolactone) (PCL) for bone tissue engineering. However, most of previous scaffolds have lacked the structural and mechanical strength to engineer bone tissue constructs with suitable biological functions. Here, we developed bioactive and relatively robust hybrid scaffolds composed of diopside nanopowder embedded PCL electrospun nanofibers. Incorporation of various concentrations of diopside nanopowder from 0 to 3 wt % within the PCL scaffolds notably improved tensile strength (eight-fold) and elastic modulus (two-fold). Moreover, the addition of diopside nanopowder significantly improved bioactivity and degradation rate compared to pure PCL scaffold which might be due to their superior hydrophilicity. We investigated the proliferation and spreading of SAOS-II cells on electrospun scaffolds. Notably, electrospun PCL-diopside scaffolds induced significantly enhanced cell proliferation and spreading. Overall, we concluded that PCL-diopside scaffold could potentially be used to develop clinically relevant constructs for bone tissue engineering. However, the extended in vivo studies are essential to evaluate the role of PCL-diopside fibrous scaffolds on the new bone growth and regeneration. Therefore, in vivo studies will be the subject of our future work. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44433. [ABSTRACT FROM AUTHOR]

We have investigated the combination effects of bioceramics and poly(lactide-co-glycolide) (PLGA) on bone reconstruction in calvarial critical size defects using a rat model. Willemite (Zn2SiO4) ceramics were prepared and coated on the surface of electrospun fabricated scaffolds. After scaffolds and nanoparticles characterization, osteoconductivity of the construct was analyzed using digital mammography, multislice spiral-computed tomography (MSCT) imaging, and histological analysis. Eight weeks after implantation, no sign of inflammation was observed at the site of the osseous defect. The results showed that the ceramics supported bone regeneration and highest bone reconstruction were observed in willemite-coated PLGA. This suggests that electrospun PLGA nanofibers coated with BG are potential candidate implants for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]