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In the past decades, iron has been one of the intensively studied biodegradable metals due to its suitable mechanical properties, but it suffers from slow degradation in a physiological environment and low bioactivity. In this work, the beneficial properties of ceramic and polymer coatings were merged to enhance the corrosion properties and biological compatibility of Fe-based biomaterials. A new bilayer coating for Fe-based biomaterials that speeds up degradation while offering controlled, localized drug release to prevent infections was prepared. In addition, bioactive coatings with an incorporated antibiotic (gentamicin, Ge) were produced to introduce antibacterial properties into the prepared biomaterials and thus increase their bioactivity. The calcium phosphate (CaP) coating layer as well as a bioactive coating layer of CaP doped with gentamicin was electrochemically deposited onto an iron substrate. A layer of poly(ethylene glycol) was subsequently applied to the selection of prepared specimens to create a bilayer ceramic/polymer coating. Electrochemical and immersion corrosion tests revealed that the application of a bilayer coating allowed achieving the desired acceleration of degradation, while the application of only a ceramic coating led to a reduction in the corrosion rate. A slight increase in the corrosion rate was observed for samples with bioactive drug-containing coatings compared to samples with drug-free coatings. Higher viability of human fibroblastic cells cultured in the extracts of the tested samples was noted for samples with a bilayer coating compared to a ceramic coating. The addition of gentamicin in the bioactive coatings had no significant effect on the viability value. Antibacterial tests proved the antibacterial activity of samples with a gentamicin-loaded coating layer against Escherichia coli and Staphylococcus aureus strains. A detailed study of the release of gentamicin from the prepared coatings revealed a different mechanism of drug release from the ceramic and the ceramic/polymer coating. Furthermore, it was found that the drug was released more slowly and uniformly from the bilayer coating. It is therefore possible to adjust the amount and duration of drug release from the bioactive coating by the thickness of the upper polymer layer. Incorporation of an antibiotic in a combined ceramic/polymer coating enabled the creation of a high-performance bioactive coating for Fe bone implants with the possibility to release a drug in the vicinity of the implant in a controlled manner to address the needs of the patient., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

The work is focused on the degradation, cytotoxicity, and antibacterial properties, of iron-based biomaterials with a bioactive coating layer. The foam and the compact iron samples were coated with a polyethylene glycol (PEG) polymer layer without and with gentamicin sulfate (PEG + Ge). The corrosion properties of coated and uncoated samples were studied using the degradation testing in Hanks' solution at 37 °C. The electrochemical and static immersion corrosion tests revealed that the PEG-coated samples corroded faster than samples with the bioactive PEG + Ge coating and uncoated samples. The foam samples corroded faster compared with the compact samples. To determine the cytotoxicity, cell viability was monitored in the presence of porous foam and compact iron samples. The antibacterial activity of the samples with PEG and PEG + Ge against Escherichia coli CCM 3954 and Staphylococcus aureus CCM 4223 strains was also tested. Tested PEG + Ge samples showed significant antibacterial activity against both bacterial strains. Therefore, the biodegradable iron-based materials with a bioactive coating could be a suitable successor to the metal materials studied thus far as well as the materials used in the field of medicine., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Advances in biomedicine and development of modern technologies in the last century have fostered the improvement in human longevity and well-being. This progress simultaneously initiated the need for novel biomaterials. Recently, degradable metallic biomaterials have attracted serious attention in scientific and clinical research owing to their utilization in some specific applications. This work investigates the effect of the polyethylene glycol (PEG) coating of open-cell iron and phosphorus/iron foams on their microstructure and corrosion properties. The addition of phosphorus causes a slight increase in pore size and the deposition of a polymer coating results in a smoothened surface and a moderate decrease in pore diameter. The PEG coating leads to an increase in corrosion rates in both foams and potentially a more desirable product.

Telomeres, nucleoprotein structures at the ends of eukaryotic chromosomes, are crucial for the maintenance of genome integrity. While the lengths of telomeres at birth are determined genetically, many factors including environmental and living conditions affect the telomere lengths during a lifespan. In this context, extreme and long-term stress has been shown to negatively impact telomeres and their protective function, with even offspring being influenced by the stress experienced by parents. Using quantitative PCR, the relative lengths of telomeres of survivors of the Holocaust during World War II and two generations of their offspring were analyzed. These data were related to those of control groups, persons of comparable age without a strong life stress experience. In contrast to previous studies of other stress-exposed groups, the relative lengths of telomeres were comparable in groups of persons exposed to Holocaust-related stress and their progenies, and in control groups. Interestingly, shorter telomeres of Holocaust survivors of the age under 12 in the year 1945 compared to Holocaust survivors of the age above 12 were detected. Our results are discussed with respect to certain exceptionality of persons having been able to cope with an extreme stress more than 70 years ago and living to a very old age., (Copyright © 2019 Elsevier Ltd. All rights reserved.)