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Background: The aim of this study was to investigate the phenotypic features (adherence, biofilm formation, virulence, antibiotic susceptibility) and the genetic background of antibiotic resistance in nosocomial ESCAPE strains consecutively isolated from surgical wound infections in hospitalized patients.

Background: Cellulose derivatives are gaining much attention in medical research due to their excellent properties such as biocompatibility, hydrophilicity, non-toxicity, sustainability, and low cost. Unfortunately, cellulose does not exhibit antimicrobial activity. However, derivatives like hydroxyethyl cellulose represent a proper matrix to incorporate antimicrobial agents with beneficial therapeutic effects. Methods: Combining more antimicrobial agents into a single composite material can induce stronger antibacterial activity by synergism. Results: Therefore, we have obtained a hydroxyethyl-cellulose-based material loaded with zinc oxide nanoparticles and cinnamon essential oil as the antimicrobial agents. The cinnamon essential oil was loaded in mesoporous silica particles to control its release. Conclusions: The composite films demonstrated high antibacterial activity against Staphylococcus aureus and Escherichia coli strains, impairing the bacterial cells' viability and biofilm development. Such antimicrobial films can be used in various biomedical applications such as topical dressings or as packaging for the food industry. [ABSTRACT FROM AUTHOR]

With the increasing use of invasive, interventional, indwelling, and implanted medical devices, healthcare-associated infections caused by pathogenic biofilms have become a major cause of morbidity and mortality. Herein, we present the fabrication, characterization, and in vitro evaluation of biocompatibility and anti-biofilm properties of new coatings based on Fe3O4 nanoparticles (NPs) loaded with usnic acid (UA) and ceftriaxone (CEF). Sodium lauryl sulfate (SLS) was employed as a stabilizer and modulator of the polarity, dispersibility, shape, and anti-biofilm properties of the magnetite nanoparticles. The resulting Fe3O4 functionalized NPs, namely Fe3O4@SLS, Fe3O4@SLS/UA, and Fe3O4@SLS/CEF, respectively, were prepared by co-precipitation method and fully characterized by XRD, TEM, SAED, SEM, FTIR, and TGA. They were further used to produce nanostructured coatings by matrix-assisted pulsed laser evaporation (MAPLE) technique. The biocompatibility of the coatings was assessed by measuring the cell viability, lactate dehydrogenase release, and nitric oxide level in the culture medium and by evaluating the actin cytoskeleton morphology of murine pre-osteoblasts. All prepared nanostructured coatings exhibited good biocompatibility. Biofilm growth inhibition ability was tested at 24 h and 48 h against Staphylococcus aureus and Pseudomonas aeruginosa as representative models for Gram-positive and Gram-negative bacteria. The coatings demonstrated good biocompatibility, promoting osteoblast adhesion, migration, and growth without significant impact on cell viability or morphology, highlighting their potential for developing safe and effective antibacterial surfaces. [ABSTRACT FROM AUTHOR]

Food safety and quality are major concerns in the food industry. Despite numerous studies, polyethylene remains one of the most used materials for packaging due to industry reluctance to invest in new technologies and equipment. Therefore, modifications to the current materials are easier to implement than adopting whole new solutions. Antibacterial activity can be induced in low-density polyethylene films only by adding antimicrobial agents. ZnO nanoparticles are well known for their strong antimicrobial activity, coupled with low toxicity and UV shielding capability. These characteristics recommend ZnO for the food industry. By incorporating such safe and dependable antimicrobial agents in the polyethylene matrix, we have obtained composite films able to inhibit microorganisms' growth that can be used as packaging materials. Here we report the obtaining of highly homogenous composite films with up to 5% ZnO by a melt mixing process at 150 °C for 10 min. The composite films present good transparency in the visible domain, permitting consumers to visualize the food, but have good UV barrier properties. The composite films exhibit good antimicrobial and antibiofilm activity from the lowest ZnO composition (1%), against both Gram-positive and Gram-negative bacterial strains. The homogenous dispersion of ZnO nanoparticles into the polyethylene matrix was assessed by Fourier transform infrared microscopy and scanning electron microscopy. The optimal mechanical barrier properties were obtained for composition with 3% ZnO. The thermal analysis indicates that the addition of ZnO nanoparticles has increased thermal stability by more than 100 °C. The UV-Vis spectra indicate a low transmittance in the UV domain, lower than 5%, making the films suitable for blocking photo-oxidation processes. The obtained films proved to be efficient packaging films, successfully preserving plum (Rome) tomatoes for up to 14 days. [ABSTRACT FROM AUTHOR]

The pathogenesis of chronic wounds (CW) involves a multifaceted interplay of biochemical, immunological, hematological, and microbiological interactions. Biofilm development is a significant virulence trait which enhances microbial survival and pathogenicity and has various implications on the development and management of CW. Biofilms induce a prolonged suboptimal inflammation in the wound microenvironment, associated with delayed healing. The composition of wound fluid (WF) adds more complexity to the subject, with proven pro-inflammatory properties and an intricate crosstalk among cytokines, chemokines, microRNAs, proteases, growth factors, and ECM components. One approach to achieve information on the mechanisms of disease progression and therapeutic response is the use of multiple high-throughput 'OMIC' modalities (genomic, proteomic, lipidomic, metabolomic assays), facilitating the discovery of potential biomarkers for wound healing, which may represent a breakthrough in this field and a major help in addressing delayed wound healing. In this review article, we aim to summarize the current progress achieved in host–microbiome crosstalk in the spectrum of CW healing and highlight future innovative strategies to boost the host immune response against infections, focusing on the interaction between pathogens and their hosts (for instance, by harnessing microorganisms like probiotics), which may serve as the prospective advancement of vaccines and treatments against infections. [ABSTRACT FROM AUTHOR]

In recent years, a significant number of epidemiological variations have been observed for fungal infections. In immunocompromised patients, Candida albicans is crucially involved in invasive infections, mostly originating in respiratory tract colonization. The global rise in candidiasis has led researchers to investigate possible correlations between fungal strains virulence profiles and their pathogenic potential, among the most investigated genes being those involved in adherence and biofilm development. In this study, we established the adherence gene profiles of C. albicans strains isolated from respiratory tract secretions in patients hospitalized for cardiovascular diseases and correlated them with the ability of the respective strains to colonize the epithelial cells and form biofilms on the inert substratum. The strains isolated from the lower respiratory tract exhibited the highest adherence capacity and were intensive biofilm producers. The SAP9, ALS3, ALS5, and ALS6 genes were the most frequently detected. There was a significant association between the presence of ALS 3 gene and the cellular substrate colonizing potential of the harboring strains. We also found that the strains expressing SAP9 were more virulent in the phenotypic assays. Detecting the presence of adherence genes from different clinical isolates is a cost-effective tool that would allow researchers to predict the virulence of a certain strain and estimate its potential to adhere to host cells and develop biofilms.

This editorial from the journal Frontiers in Microbiology discusses the gender gap in scientific fields, particularly in terms of publishing and patenting. It also addresses the underrepresentation of women in authorship and citations. The editorial introduces a research topic on women in infectious agents and disease, which includes seven original articles and two reviews covering various topics such as Streptococcus agalactiae strains, Group B Streptococcus colonization in pregnant women, and metabolic changes in Mycobacterium tuberculosis-infected macrophages. The authors highlight the lack of research on fungi in the neonatal microbiome, despite their significant presence in gut microbes of neonates. They emphasize the need for studies on fungi as fungal infections remain a major cause of illness and death in premature infants. The document concludes with acknowledgments and declarations of no financial support or conflicts of interest. [Extracted from the article]

To modulate the bioactivity and boost the therapeutic outcome of implantable metallic devices, biodegradable coatings based on polylactide (PLA) and graphene oxide nanosheets (nGOs) loaded with Zinforo™ (Zin) have been proposed in this study as innovative alternatives for the local management of biofilm-associated periprosthetic infections. Using a modified Hummers protocol, high-purity and ultra-thin nGOs have been obtained, as evidenced by X-ray diffraction (XRD) and transmission electron microscopy (TEM) investigations. The matrix-assisted pulsed laser evaporation (MAPLE) technique has been successfully employed to obtain the PLA-nGO-Zin coatings. The stoichiometric and uniform transfer was revealed by infrared microscopy (IRM) and scanning electron microscopy (SEM) studies. In vitro evaluation, performed on fresh blood samples, has shown the excellent hemocompatibility of PLA-nGO-Zin-coated samples (with a hemolytic index of 1.15%), together with their anti-inflammatory ability. Moreover, the PLA-nGO-Zin coatings significantly inhibited the development of mature bacterial biofilms, inducing important anti-biofilm efficiency in the as-coated samples. The herein-reported results evidence the promising potential of PLA-nGO-Zin coatings to be used for the biocompatible and antimicrobial surface modification of metallic implants. [ABSTRACT FROM AUTHOR]

Exploring silver-based and carbon-based nanomaterials' excellent intrinsic antipathogenic effects represents an attractive alternative for fabricating anti-infective formulations. Using chemical synthesis protocols, stearate-conjugated silver (Ag@C18) nanoparticles and graphene oxide nanosheets (nGOs) were herein obtained and investigated in terms of composition and microstructure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) characterizations revealed the formation of nanomaterials with desirable physical properties, while X-ray diffraction (XRD) analyses confirmed the high purity of synthesized nanomaterials. Further, laser-processed Ag@C18-nGO coatings were developed, optimized, and evaluated in terms of biological and microbiological outcomes. The highly biocompatible Ag@C18-nGO nanostructured coatings proved suitable candidates for the local modulation of biofilm-associated periprosthetic infections. [ABSTRACT FROM AUTHOR]

The biodeterioration of the natural surface on monuments, historical buildings, and even public claddings brings to the attention of researchers and historians the issues of conservation and protection. Natural stones undergo changes in their appearance, being subjected to deterioration due to climatic variations and the destructive action of biological systems interfering with and living on them, leading to ongoing challenges in the protection of the exposed surfaces. Nanotechnology, through silver nanoparticles with strong antimicrobial effects, can provide solutions for protecting natural surfaces using specific coupling agents tailored to each substrate. In this work, surfaces of two common types of natural stone, frequently encountered in landscaping and finishing works, were modified using siloxane coupling agents with thiol groups. Through these agents, silver nanoparticles (AgNPs) were fixed, exhibiting distinct characteristics, and subjected to antimicrobial analysis. This study presents a comparative analysis of the efficiency of coupling agents that can be applied to a natural surface with porous structures, when combined with laboratory-obtained silver nanoparticles, in reducing the formation of microbial biofilms, which are a main trigger for stone biodeterioration. [ABSTRACT FROM AUTHOR]