In our previous work, we reported alterations in protamines/histones ratio, in DNA binding of these proteins and their involvement in DNA oxidative damage in 84% of the young men living in the Land of Fires. In the present work, we extended our findings, evaluating any alterations in spermatozoa of a family case, a father and son, living in this area, to also give a first look at the possibility of transgenerational inherited effects of environmental contaminants on the molecular alterations of sperm nuclear basic proteins (SNBP), DNA and semen parameters. In the father and son, we found a diverse excess of copper and chromium in the semen, different alterations in SNBP content and low DNA binding affinity of these proteins. In addition, DNA damage, in the presence of CuCl2 and H2O2, increased by adding both the father and son SNBP. Interestingly, son SNBP, unlike his father, showed an unstable DNA binding and were able to produce DNA damage even without external addition of CuCl2, in line with a lower seminal antioxidant activity than the father. The peculiarity of some characteristics of son semen could be a basis for possible future studies on transgenerational effects of pollutants on fertility.
The increase in multidrug-resistant bacteria represents a true challenge in the pharmaceutical and biomedical fields. For this reason, research on the development of new potential antibacterial strategies is essential. Here, we describe the development of a green system for the synthesis of silver nanoparticles (AgNPs) bioconjugated with chitosan. We optimized a Prunus cerasus leaf extract as a source of silver and its conversion to chitosan–silver bioconjugates (CH-AgNPs). The AgNPs and CH-AgNPs were characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transform infrared spectroscopy (FT-IR), ultraviolet–visible spectroscopy (UV–Vis), and zeta potential measurement (Z-potential). The cytotoxic activity of AgNPs and CH-AgNPs was assessed on Vero cells using the 3-[4.5-dimethylthiazol-2-yl]-2.5-diphenyltetrazolium bromide (MTT) cell proliferation assay. The antibacterial activity of AgNPs and CH-AgNPs synthesized using the green system was determined using the broth microdilution method. We evaluated the antimicrobial activity against standard ATCC and clinically isolated multisensitive (MS) and multidrug-resistant bacteria (MDR) Escherichia coli (E. coli), Enterococcus faecalis (E. faecalis), Klebsiella pneumonia (K. pneumoniae), and Staphylococcus aureus (S. aureus), using minimum inhibitory concentration (MIC) assays and the broth dilution method. The results of the antibacterial studies demonstrate that the silver chitosan bioconjugates were able to inhibit the growth of MDR strains more effectively than silver nanoparticles alone, with reduced cellular toxicity. These nanoparticles were stable in solution and had wide-spectrum antibacterial activity. The synthesis of silver and silver chitosan bioconjugates from Prunus cerasus leaf extracts may therefore serve as a simple, ecofriendly, noncytotoxic, economical, reliable, and safe method to produce antimicrobial compounds with low cytotoxicity.
SARS-CoV-2 has become one of the most studied viruses of the last century. It was assumed that the only possible host for these types of viruses was mammalian eukaryotic cells. Our recent studies show that microorganisms in the human gastrointestinal tract affect the severity of COVID-19 and for the first time provide indications that the virus might replicate in gut bacteria. In order to further support these findings, in the present work, cultures of bacteria from the human microbiome and SARS-CoV-2 were analyzed by electron and fluorescence microscopy. The images presented in this article, in association with the nitrogen (15N) isotope-labeled culture medium experiment, suggest that SARS-CoV-2 could also infect bacteria in the gut microbiota, indicating that SARS-CoV-2 could act as a bacteriophage. Our results add new knowledge to the understanding of the mechanisms of SARS-CoV-2 infection and fill gaps in the study of the interactions between SARS-CoV-2 and non-mammalian cells. These findings could be useful in suggesting specific new pharmacological solutions to support the vaccination campaign.