Generation of cardiomyocytes from stem cells cultured on nanofibrous scaffold: Experimental approach for attenuation of myocardial infarction.

The current study was constructed to fabricate polyamide based nanofibrous scaffolds (NS) and to define the most promising one for the generation of cardiomyocytes from adipose tissue derived mesenchymal stem cells (ADMSCs). This purpose was extended to assess the potentiality of the generated cardiomyocytes in relieving myocardial infarction (MI) in rats. Production and characterization of NSs were carried out. ADMSCs were cultured on NS and induced to differentiate into cardiomyocytes by specific growth factors. Molecular analysis for myocyte-specific enhancer factor 2 C (MEF2C) and alpha sarcomeric actin (α-SCA) expression was done to confirm the differentiation of ADMSCs into cardiomyocytes for further transplantation into MI induced rats. Implantation of cells in MI afflicted rats boosted heart rate, ST height and PR interval and lessened P duration, RR, QTc and QRS intervals. Also, this type of medication minified serum lactate dehydrogenase (LDH) and creatine kinase-MB (CK-MB) enzymes activity as well as serum and cardiac troponin T (Tn-T) levels and upraised serum and cardiac α-SCA and cardiac connexin 43 (CX 43) levels. Microscopic feature of cardiac tissue sections of rats in the treated groups revealed great renovation in the cardiac microarchitecture. Conclusively, this attempt gains insight into a realistic strategy for recovery of MI through systemic employment of in vitro generated cardiomyocytes.

Cell migration, DNA fragmentation and antibacterial properties of novel silver doped calcium polyphosphate nanoparticles.

To combat infections, silver was used extensively in biomedical field but there was a need for a capping agent to eliminate its cytotoxic effects. In this study, polymeric calcium polyphosphate was doped by silver with three concentrations 1, 3 or 5 mol.% and were characterized by TEM, XRD, FTIR, TGA. Moreover, cytotoxicity, antibacterial, cell migration and DNA fragmentation assays were done to assure its safety. The results showed that the increase in silver percentage caused an increase in particle size. XRD showed the silver peaks, which indicated that it is present in its metallic form. The TGA showed that thermal stability was increased by increasing silver content. The antibacterial tests showed that the prepared nanoparticles have an antibacterial activity against tested pathogens. In addition, the cytotoxicity results showed that the samples exhibited non-cytotoxic behavior even with the highest doping concentration (5% Ag-CaPp). The cell migration assay showed that the increase in the silver concentration enhances cell migration up to 3% Ag-CaPp. The DNA fragmentation test revealed that all the prepared nanoparticles caused no fragmentation. From the results we can deduce that 3% Ag-CaPp was the optimum silver doped calcium polyphosphate concentration that could be used safely for medical applications.

Investigation of novel HCV therapies: Boscia angustifalia & Boscia senegalensis extracts loaded on galactosylated chitosan nanoparticles synthesized by eco-friendly method for HCV treatment.

Hepatitis C virus (HCV) is a major causative agent of chronic liver diseases including chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma worldwide. Treatment of HCV has evolved from early interferon monotherapy to the current all-oral regimens using direct-acting antivirals. However, antiviral resistance has become a critical issue in the treatment of chronic hepatitis C after receiving therapy with direct-acting antivirals (DAA) with a 0.5 % chance of the hepatitis C virus recurrence, similar to other chronic viral infections. So, retreatment options following treatment failure have become crucial issues. Hence, this study aims to investigate a new promising therapy for HCV. In the field of nanomedicine, chitosan nanoparticles are well-known delivery systems that are frequently used as polymeric carriers. Galactosylated chitosan nanoparticles have been widely applied in HCV treatment. In this study, we have modified galactosylation by an eco-friendly method using l-ascorbic instead of hazardous reagents and we have loaded it with newly tested two Boscia extracts each in three different concentrations. The synthesized chitosan nanoparticles showed two dispersion peaks, at 196 ± 29 nm and 1.33 ± 0.36 µm, with a zeta potential of +3.3 ± 0.4mV with high stability in a range of 40.7 mV. The percentage of encapsulation of Boscia angustifalia extract was found to be 46.58 ± 1.33 % and for Boscia senegalensis extract was 9.77 ± 0.33 %. The release of Boscia angustifalia extract from the nanoparticles was about 40 % in acidic media after 180 min and about 60 % in normal pH. However, the release of Boscia senegalensis extract was 20 % in acidic media and 56 % in normal media after 24 h. Testing of these two newly developed composites against HCV was carried out using an in vitro system for the production of hepatitis C virus (HCV) which was established by infection of human hepatoma cells. Evidence for persistent virus production was monitored by the ELISA technique using an anti-HCV-specific antibody. Results obtained showed that all samples had an anti-HCV activity that increased by increasing concentration, and Boscia angustifalia had remarkable anti-HCV activity compared to Boscia senegalensis.

Antiviral Electrospun Polyamide Three-Layered Mask Filter Containing Metal Oxide Nanoparticles and Black Seed Oil.

Upon the tremendous spread of coronavirus, there is a need to develop biodegradable, multifunctional, antiviral masks that can be safely used without polluting the environment as conventional surgical masks do. In this study, a three-layered mask filter is designed and fabricated. The first two layers contain electrospun polyamide with dispersed nanoparticles (NPs) of TiO2 and ZnO prepared via breakdown anodization. The third layer is composed of Nigella sativa oil (black seed oil) electrospun with polyamide and blended with chitosan to form an effective antiviral three-layered mask filter. The morphological characterization revealed the nanoscale features of the fabricated nanofibers with the ZnO and TiO2 NPs being embedded in the polymeric matrix. The specimens showed good wettability, which is necessary for virus attachment and its subsequent decay. The assembled mask has shown very good mechanical properties. The cytotoxicity results revealed that the proposed mask filter has less cytotoxic effect on the A549 cell line than the commercial KN95 mask filter with maintaining a cell viability of 65.3%. The antiviral activity test showed a variable virucidal effect against human adenovirus on A549 cells. The proposed mask showed the highest effect on the virus followed by PA-ZnO and PA-TiO2 films, which supports the assumption that the used NPs may have broad and promising effects on viruses when combined with the electrospun films.

Cytocompatibility of MG-63 osteosarcoma cells on chitosan/hydroxyapatite/lignin hybrid composite scaffoldin vitro.

This study aims at fabricating promising cytocompatible hybrid biocomposite scaffolds from chitosan (CS), hydroxyapatite (HAP) and lignin (L) for bone tissue engineering by using freeze-drying technique. Different ratios of HAP to L (50:0, 37.5:12.5, 25:25 and 12.5:37.5) were taken to determine the optimum ratio for obtaining a composite with superior properties. The mechanical and biological properties of the resulting composites were investigated. The mechanical results showed that the prepared composite with a ratio of 25:25 of HAP/L exhibited a remarkable enhancement in the mechanical properties compared to the others. Additionally, it was found from thein vitroresults that the addition of L enhanced the water uptake value of the resulting scaffolds indicating their increased hydrophilicity. As a result, a significant increase in the attachment and proliferation of MG-63 cell line (osteoblast like cells) was observed in composite scaffolds with L over the scaffold without L (CS/HAP). From these results, it could be suggested that the prepared composite scaffold with 25:25 of HAP/L is very promising biomaterials in bone tissue-engineering as it exhibited a better mechanical and biological properties than the other prepared composites.