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This work aims to investigate the influence of the substrate temperature on low‐pressure plasma polymerization processes. Emphasis is placed on the mechanical properties and growth mechanism of the plasma polymer films (PPFs). For this purpose, two precursors are considered, differing only by their unsaturation degree: 2‐propen‐1‐ol (CH2═CH–CH2–OH) and propan‐1‐ol (CH3–CH2–CH2–OH). Although propan‐1‐ol‐based PPFs behave like hard elastic solids, 2‐propen‐1‐ol‐based coatings evolve from a liquid film to an elastic solid on increasing the substrate temperature. This behavior is understood considering the evolution of the glass transition temperature of PPFs. The latter is correlated with the cross‐linking degree of the polymeric network governed by the energy density of bombarding ions on the growing film. [ABSTRACT FROM AUTHOR]

Aims The purpose of this work was to study extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (ESBL-EC) in freshwaters, hospital effluents, and wastewaters during two sampling campaigns in 2021. Methods and results Water sampling was performed at 24 stations in the Ourthe watershed in Belgium. A total of 644 ESBL (n  = 642) and AmpC (n  = 2) E. coli strains were isolated. Disk-diffusion assays were performed following the EUCAST's recommendations. All strains were tested for the presence of bla CTX-M-1, bla CTX-M-2, and bla CTX-M-9 gene groups by PCR. Genes belonging to bla CTX-M-1 and bla CTX-M-9 groups were detected, respectively, in 73.6% and 14.9% of the strains. No bla CTX-M-2 group's gene was found. A subset of strains (n  = 40) was selected for whole genome sequencing. Escherichia coli serotype O18: H7 ST 1463 was predominant (n  = 14) in the sequenced strains and showed pathogenicity in the Galleria mellonella larvae model. β-lactamase genes identified were bla CTX-M (n  = 21), with bla CTX-M-15 mostly represented (n  = 15), as well as bla TEM (n  = 11), bla OXA (n  = 7), bla SHV (n  = 9), and carbapenemase (CP) genes were observed in several strains— bla KPC-3 (n  = 19), bla NDM-1 (n  = 1), bla VIM-1 (n  = 2), and bla OXA-244 (n  = 2)—even from freshwaters. Conclusions ESBL-EC are widely distributed in the aquatic environment in Belgium and contain a variety of ESBL and CP genes. [ABSTRACT FROM AUTHOR]

Aims Understanding bacterial phage resistance mechanisms has implications for developing phage-based therapies. This study aimed to explore the development of phage resistance in Escherichia coli K1 isolates' to K1-ULINTec4, a K1-dependent bacteriophage. Methods and results Resistant colonies were isolated from two different strains (APEC 45 and C5), both previously exposed to K1-ULINTec4. Genome analysis and several parameters were assessed, including growth capacity, phage adsorption, phenotypic impact at capsular level, biofilm production, and virulence in the in vivo Galleria mellonella larvae model. One out of the six resistant isolates exhibited a significantly slower growth rate, suggesting the presence of a resistance mechanism altering its fitness. Comparative genomic analysis revealed insertion sequences in the region 2 of the kps gene cluster involved in the capsule biosynthesis. In addition, an immunoassay targeting the K1 capsule showed a very low positive reaction compared to the control. Nevertheless, microscopic images of resistant strains revealed the presence of capsules with a clustered organization of bacterial cells and biofilm assessment showed an increased biofilm production compared to the sensitive strains. In the G. mellonella model, larvae infected with phage-resistant isolates showed better survival rates than larvae infected with phage-sensitive strains. Conclusions A phage resistance mechanism was identified at the genomic level and had a negative impact on the K1 capsule production. The resistant isolates showed an increased biofilm production and a decreased virulence in vivo. [ABSTRACT FROM AUTHOR]

This work aims to provide new insights into the link between the growth mechanisms of functionalized plasma polymer films (PPFs) and the substrate temperature (TS). By means of AFM‐based techniques, it has been demonstrated that the mechanical behavior of the coatings is dramatically affected by TS and the precursor employed (i.e., 1‐propanethiol or 1‐propylamine). While propylamine‐based PPFs behave as hard elastic materials regardless of TS, propanethiol‐based PPFs evolve from viscous liquids to elastic solids with increasing TS. This behavior can be understood considering the glass transition temperature of PPF. For both precursors, the latter is correlated to the cross‐linking density controlled through the energy density brought by positive ions to the growing film. [ABSTRACT FROM AUTHOR]

Understanding the electronic structure of photocatalysts is crucial for enhancing their efficiency. In this study, we have successfully synthesized novel monoclinic bismuth vanadate (Bi7VO13) nanoparticles using the gas phase condensation technique, with an average particle size of 40 nm. To investigate the crystallographic structure of the as-synthesized nanoparticles, we conducted X-ray diffraction (XRD) experiments. Additionally, we employed advanced characterization techniques to provide a detailed analysis of the electronic structure of Bi7VO13 nanoparticles. This study presents the first report on the electronic structure of Bi7VO13 nanoparticles using the aforementioned spectroscopic methods. Remarkably, the investigation revealed that the valence band maximum (VB) and conduction band minimum (CB) are dominated by O 2p and V 3d states, respectively. Moreover, X-ray absorption spectroscopy (XAS) reveals splitting the V 3d conduction band state into a triplet d-manifold at the V L-edge and O K-edge. This splitting arises from the lattice distortion induced by lone pairs, which gives rise to a band gap of 2.28 eV. Under visible light irradiation, the Bi7VO13 nanoparticles exhibit efficient visible light absorption, highlighting their potential for photocatalytic applications. Notably, our experiments demonstrated outstanding photodegradation properties of methylene blue, serving as a model effluent, further underscoring the photocatalytic progress of Bi7VO13 nanoparticles. In conclusion, this research explains the functioning of Bi7VO13 photocatalysts and opens the doors for utilizing their potential to generate a cleaner and brighter future. [ABSTRACT FROM AUTHOR]

Phage therapy is recognized to be a promising alternative to fight antibiotic-resistant infections. In the quest for oral dosage forms containing bacteriophages, the utilization of colonic-release Eudragit® derivatives has shown potential in shielding bacteriophages from the challenges encountered within the gastrointestinal tract, such as fluctuating pH levels and the presence of digestive enzymes. Consequently, this study aimed to develop targeted oral delivery systems for bacteriophages, specifically focusing on colon delivery and employing Eudragit® FS30D as the excipient. The bacteriophage model used was LUZ19. An optimized formulation was established to not only preserve the activity of LUZ19 during the manufacturing process but also ensure its protection from highly acidic conditions. Flowability assessments were conducted for both capsule filling and tableting processes. Furthermore, the viability of the bacteriophages remained unaffected by the tableting process. Additionally, the release of LUZ19 from the developed system was evaluated using the Simulator of the Human Intestinal Microbial Ecosystem (SHIME®) model. Finally, stability studies demonstrated that the powder remained stable for at least 6 months when stored at +5 °C. [ABSTRACT FROM AUTHOR]