Potential biodegradable face mask to counter environmental impact of Covid-19.

On the eve of the outbreak of the COVID-19 pandemic, there is a tremendous increase in the production of facemasks across the world. The primary raw materials for the manufacturing of the facemasks are non-biodegradable synthetic polymers derived from petrochemicals. Disposal of these synthetic facemasks increases waste-load in the environment causing severe ecological issues for flora and fauna. The synthesis processes of the polymers from the petrochemical by-products were also not eco-friendly, which releases huge greenhouse and harmful gases. Therefore, many research organizations and entrepreneurs realize the need for biodegradable facemasks to render similar performance as the existing non-biodegradable masks. The conventional textile fabrics made of natural fibers like cotton, flax, hemp, etc., can also be used to prepare facemasks with multiple layers in use for general protection. Such natural textile masks can be made anti-microbial by applying various herbal anti-microbial extracts like turmeric, neem, basil, aloe vera, etc. As porosity is the exclusive feature of the masks for arresting tiny viruses, the filter of the masks should have a pore size in the nanometre scale, and that can be achieved in nanomembrane manufactured by electrospinning technology. This article reviews the various scopes of electrospinning technology for the preparation of nanomembrane biomasks. Besides protecting us from the virus, the biomasks can be useful for skin healing, skincare, auto-fragrance, and organized cooling which are also discussed in this review article.

3D Propolis-Sodium Alginate Scaffolds: Influence on Structural Parameters, Release Mechanisms, Cell Cytotoxicity and Antibacterial Activity.

In this study, the main aim was to fabricate propolis (Ps)-containing wound dressing patches using 3D printing technology. Different combinations and structures of propolis (Ps)-incorporated sodium alginate (SA) scaffolds were developed. The morphological studies showed that the porosity of developed scaffolds was optimized when 20% (v/v) of Ps was added to the solution. The pore sizes decreased by increasing Ps concentration up to a certain level due to its adhesive properties. The mechanical, swelling-degradation (weight loss) behaviors, and Ps release kinetics were highlighted for the scaffold stability. An antimicrobial assay was employed to test and screen antimicrobial behavior of Ps against Escherichia coli and Staphylococcus aureus strains. The results show that the Ps-added scaffolds have an excellent antibacterial activity because of Ps compounds. An in vitro cytotoxicity test was also applied on the scaffold by using the extract method on the human dermal fibroblasts (HFFF2) cell line. The 3D-printed SA-Ps scaffolds are very useful structures for wound dressing applications.

Development of Amoxicillin-Loaded Electrospun Polyurethane/Chitosan/ $\beta$ -Tricalcium Phosphate Scaffold for Bone Tissue Regeneration.

Biocompatible nanocomposite electrospun fibers containing Polyurethane/Chitosan/ $\beta $ -Tri calcium phosphate with diverse concentrations were designed and produced through the electrospinning process for bone tissue engineering applications. After the production process, density measurement, viscosity, electrical conductivity, and tensile strength measurement tests were carried out as physical analyses of blended solutions. The chemical structural characterization was scrutinized using Fourier transform infrared spectrometer (FTIR), and scanning electron microscopy (SEM) was used to observe the morphological details of developed electrospun scaffolds. Cell viability, attachment, and proliferation were performed using a L929 fibroblast cell line. Based on the physical, SEM, FTIR analysis, and cell culture studies, preferable nanofiber composition was selected for further studies. Amoxicillin (AMX) was loaded to that selected nanofiber composition for examination of the drug release. In comparison with other studies on similar AMX controlled products, higher drug loading and encapsulation efficiencies were obtained. It has been clearly found that the developed nanofiber composites have potential for bone tissue engineering applications.

Round ligament varicosities mimicking inguinal hernias in pregnancy: importance of color Doppler sonography.

Round ligament varicosities are easily misdiagnosed as an obstructed hernia in a gravid patient. When this condition is diagnosed correctly, unnecessary intervention may be prevented. We aimed to determine the significance of round ligament varicosities in pregnancy and to describe their clinical presentation and sonographic appearance.