Background Growing investigations demonstrate that graphene oxide (GO) has an undeniable impact on repairing damaged bone tissue. Moreover, it has been stated in the literatures that poly(2-hydroxyethyl methacrylate) (PHEMA) and gelatin could provide a biocompatible structure. Methods In this research, we fabricated a scaffold using freeze-drying method comprised of PHEMA and gelatin, combined with GO. The validation of the successful fabrication of the scaffolds was performed utilizing Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction assay (XRD). The microstructure of the scaffolds was observed using scanning electron microscopy (SEM). The structural properties of the scaffolds including mechanical strength, hydrophilicity, electrical conductivity, and degradation rate were also evaluated. Human bone marrow‐derived mesenchymal stem cells (hBM-MSCs) were used to evaluate the cytotoxicity of the prepared scaffolds. The osteogenic potential of the GO-containing scaffolds was studied by measuring the alkaline phosphatase (ALP) activity after 7, 14, and 21 days cell culturing. Results SEM assay showed a porous interconnected scaffold with approximate pore size of 50–300 μm, appropriate for bone regeneration. The increase in GO concentration from 0.25 to 0.75% w/v exhibited a significant improvement in scaffolds compressive modulus from 9.03 ± 0.36 to 42.82 ± 1.63 MPa. Conventional four-probe analysis confirmed the electrical conductivity of the scaffolds in the semiconductor range. The degradation rate of the samples appeared to be in compliance with bone healing process. The scaffolds exhibited no cytotoxicity using MTT assay against hBM-MSCs. ALP analysis indicated that the PHEMA–Gel–GO scaffolds could efficiently cause the differentiation of hBM-MSCs into osteoblasts after 21 days, even without the addition of the osteogenic differentiation medium. Conclusion Based on the results of this research, it can be stated that the PHEMA–Gel–GO composition is a promising platform for bone tissue engineering.

Several ongoing investigations have been founded on the development of an optimized therapeutic strategy for the COVID-19 virus as an undeniable acute challenge for human life. Cell-based therapy and particularly, mesenchymal stem cells (MSCs) therapy has obtained desired outcomes in decreasing the mortality rate of severe acute respiratory syndrome coronavirus 2 (SARS-COV-2), mainly owing to its immunoregulatory impact that prevents the overactivation of the immune system. Also, these cells with their multipotent nature, are capable of repairing the damaged tissue of the lung which leads to reducing the probability of acute respiratory distress syndrome (ARDS). Although this cell-based method is not quite cost-effective for developing countries, regarding its promising results in order to treat SARS-COV-2, more economical evaluation as well as clinical trials should be performed for improving this therapeutic approach. Here in this article, the functional mechanism of MSCs therapy for the treatment of COVID-19 and the clinical trials based on this method will be reviewed. Moreover, its economic efficiency will be discussed.

No abstract

No abstract

Based on the remarkable demand for facial reconstitute or reshape fillers due to the dermal defects arising from specific diseases, trauma, or aging, several natural or synthetic materials have been investigated. Among the evaluated materials, decellularized dermis is one of the most biocompatible choices for the aim of skin tissue regenerative approaches. On the other hand, Carboxymethyl Cellulose (CMC), a synthetic polysaccharide, with the desirable degradability, biomechanical stability, and nontoxicity seems to be an acceptable reinforcement agent for decellularized dermis. Thus, in this research, an injectable soft tissue filler contained of human-derived decellularized collagen and CMC was fabricated. The cell-removal approving was performed utilizing H&E staining assay. The biocompatibility of the prepared samples was confirmed by MTT assay. The rheology examination demonstrated the increased storage modulus and enhanced elastic property as a consequence of CMC presence. Furthermore, the required flow force of the collagen/CMC filler was decreased as a consequence of decreasing the viscosity and its injectability was improved. According to the provided biomechanical and biological results, it could be claimed that the collagen/CMC hydrogel is a suitable substitute filler for skin tissue engineering.