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The construction of ultrathin membranes from linearly aligned π-electron systems is advantageous for targeted energy, charge, or mass transfer. The Langmuir-Blodgett (LB) technique enables the creation of such membranes, especially with amphiphilic π-electron systems. However, these systems often aggregate, forming rigid Langmuir monolayers with defects or holes. In this study we introduce plasticizers to effectively address this issue. To create anisotropic membranes, we used an oligo(phenylene ethynylene) derivative (OPE-NH 2 ) as an linear amphiphile and bisphenol A di-tert-butyl ester (BPAE) as a plasticizer. We analyzed surface pressure (mean molecular area) (Π(mma)) isotherms and characterized Langmuir monolayers with Brewster Angle Microscopy (BAM), to determine the optimal miscibility of OPE-NH 2 with BPAE. Detailed analysis of hole areas filled was performed through image binarization. We identified an optimal BPAE concentration of 4 mol-% in the OPE-NH 2 Langmuir monolayer. Our BAM image evaluation via binarization determined the difference between the mean molecular areas of close-packed Langmuir domains and those quantified via the Π(mma) isotherm. This study presents an automated method for BAM image analysis and a new approach for fabricating defect-free anisotropic molecular monolayers of π-conjugated amphiphiles., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a significant burden globally, particularly in the Arabian Gulf region. The United Arab Emirates (UAE) has experienced rising MRSA prevalence, with increasing diversity in the clonal complexes (CCs) identified. The COVID-19 pandemic, with its increased hospitalization rates and antibiotic use, may have further influenced MRSA's genetic evolution and epidemiology in the country., Methods: To investigate this influence, genomic profiling of 310 MRSA clinical isolates collected between February and November 2022 was performed using a DNA microarray-based assay., Results: Isolates were assigned to 22 clonal complexes and 72 distinct strain assignments. The predominant clonal complexes were CC5, CC6, CC361, CC22, CC1, and CC8. Community-acquired MRSA lineages were dominant, with only one healthcare-associated MRSA lineage isolate identified. Upward trends of CC1153 were observed along with rare CCs, such as CC121-MRSA and CC7-MRSA, with the latter being reported for the first time in the Arabian Gulf region. The presence of pandemic strains USA300 CC8-MRSA-[IVa + ACME1] and CC8-MRSA-IV strains were also observed, including variants lacking Panton-Valentine leukocidin ( pvl ) genes and missing tst1 or enterotoxin genes. The PVL-negative CC772-MRSA-V/VT was identified, representing its first report in the UAE. A novel variant, CC361-MRSA-IV ( tst1 +/PVL+), was identified. Pvl genes were observed in 36% of the isolates, primarily from skin and soft tissue infections, while fusC (SCC-borne fusidic acid resistance) was identified in 13% of the isolates., Conclusions: The findings highlight the ongoing evolution of MRSA in the UAE, with the persistence and emergence of diverse and rare clonal complexes, driving the need for continuous genomic surveillance.

The rising incidence of head and neck cancer represents a serious global health challenge, requiring more accurate diagnosis and innovative surgical approaches. Multimodal nonlinear optical microscopy, combining coherent anti-Stokes Raman scattering (CARS), two-photon excited fluorescence (TPEF), and second-harmonic generation (SHG) with deep learning-based analysis routines, offers label-free assessment of the tissue's morphochemical composition and allows early-stage and automatic detection of disease. For clinical intraoperative application, compact devices are required. In this preclinical study, a cohort of 15 patients was examined with a newly developed rigid CARS/TPEF/SHG endomicroscope. To detect head and neck tumor from the multimodal data, deep learning-based semantic segmentation models were used. This preclinical study yields in a diagnostic sensitivity of 88% and a specificity of 96%. To combine diagnostics with therapy, machine learning-inspired image-guided selective tissue removal was used by integrating femtosecond laser ablation into the endomicroscope. This enables a powerful approach of intraoperative "seek and treat," paving the way to advanced surgical treatment.

In the field of cattle medicine in Austria, to date, few studies have investigated the presence of methicillin-resistant Staphylococcus aureus and extended-spectrum β-lactamase-producing Escherichia coli in Austria. For this reason, milk and nasal samples were examined for the presence of methicillin-resistant Staphylococcus aureus as well as fecal samples for extended-spectrum cephalosporin-resistant Escherichia coli . The nasal and fecal swabs were collected during the veterinary treatment of calf pneumonia and calf diarrhea. For the milk samples, the first milk jets were milked into a pre-milking cup and then the teats were cleaned and disinfected before the samples were taken. The cows were selected during the veterinary visits to the farms when treatment was necessary due to mastitis. Depending on the severity of the mastitis (acute mastitis or subclinical mastitis), antibiotics and non-steroidal anti-inflammatory drugs were given immediately (acute disease) or after completion of the antibiogram (subclinical disease). Isolates were characterized by a polyphasic approach including susceptibility pheno- and genotyping and microarray-based assays. No methicillin-resistant Staphylococcus aureus was found in the milk samples, but one nasal swab was positive for methicillin-resistant Staphylococcus aureus . Twenty-two Escherichia coli isolates were detected among the fecal samples. All the Escherichia coli isolates were resistant to ceftazidime. In all the Escherichia coli isolates, genes from the bla CTX family were detected with other bla (n = 20). In total, 63.6% (n = 14) of the isolates exhibited a multidrug-resistant phenotype and one bla isolate (4.5%) harbored the AmpC gene. Precisely because the presence of data regarding extended-spectrum cephalosporin-resistant CTX-M-1/15 (n = 20). In total, 63.6% (n = 14) of the isolates exhibited a multidrug-resistant phenotype and one E. coli in calves and cows in Austria is rare, this study further expands our understanding of antimicrobial resistance in Austrian cattle, which is highly relevant for successful antibiotic therapy in sick cattle.Escherichia coli and methicillin-resistant Staphylococcus aureus in calves and cows in Austria is rare, this study further expands our understanding of antimicrobial resistance in Austrian cattle, which is highly relevant for successful antibiotic therapy in sick cattle.

π-π interactions decisively shape the supramolecular structure and functionality of π-conjugated molecular semiconductor materials. Despite the customizable molecular building blocks, predicting their supramolecular structure remains a challenge. Traditionally, force field methods have been used due to the complexity of these structures, but advances in computational power have enabled ab initio approaches such as density functional theory (DFT). DFT is particularly suitable for finding energetically favorable structures of dye aggregates, which are determined by a large number of different interactions, but a systematic aggregate search can still be very challenging due to the large number of possible geometries. In this work, we show ways to overcome this challenge. We investigate how finely translational and rotational lattices must be structured to identify all energetic minima of π-stack structures, focusing on porphyrins as a prototype challenge. Our approach involves single-point DFT calculations of systematically varied dimer geometries, identification of local energy minima, hierarchical grouping of geometrically similar structures, and optimization of the energetically favorable representatives of each geometric family. This ab initio method provides a general framework for the systematic prediction of aggregate structures and reveals geometrically diverse and energetically favorable dimers.

Background: Antimicrobial resistance (AMR) in Enterobacterales constitutes a significant threat to the health of both humans and animals and a socioeconomic problem. Enterobacterales, mainly Escherichia coli, carrying β-lactamases has become one of the main indicators to estimate the burden of AMR in animals within "One Health" approach., Objectives: To assess the presence of extended-spectrum cephalosporin-resistant Enterobacterales associated with ruminants (cattle, sheep, goats) habituated in all five provinces of Rwanda and to perform in depth characterization of isolates., Methods: We screened 454 rectal swabs from 203 cows, 170 goats, and 81 sheep and selective isolation of extended-spectrum cephalosporin-resistant Enterobacterales was conducted. Isolates were identified as a members of the order Enterobacterales by MALDI-TOF MS and further characterized by susceptibility testing and by whole-genome sequencing., Results: Out of the 454 samples, 64 extended-spectrum cephalosporin-resistant Enterobacterales were isolated from 58 animals. Isolates belonged to seven bacterial species and were identified as Escherichia coli (n = 54), Enterobacter bugandensis (n = 4), Enterobacter mori (n = 2), Klebsiella pneumoniae (n = 2), Enterobacter dykesii (n = 1), and Citrobacter freundii (n = 1). All isolates displayed an Extended-spectrum β-lactamases (ESBL) phenotype, with exception of Citrobacter freundii isolate displayed both an ESBL and AmpC phenotype. In addition, all Enterobacter isolates were identified as stably de-repressed AmpC-producers. ESBLs genes, bla CTX-M-15 was predominant. Resistance to tetracycline and tet(A) was most frequently observed among non-β-lactam resistance. Forty-eight isolates displayed multidrug-resistance phenotypes. A shiga toxin-producing E. coli and an enterotoxigenic E. coli isolate were observed. Genome comparisons revealed thirty-five E. coli sequence types (ST) (ST10, ST307 being predominate)., Conclusions: Considering the high proximity between ruminants and humans in Rwanda, the dissemination of antimicrobial drug resistance highlights the public health threats and requires the joint and multisectoral action of human and veterinary medicine, at human-animal-environment interfaces. Therefore, it is important to establish national and global "One Health" surveillance programs of AMR to tackle the antibiotic-resistant crisis in human and veterinary medicine., Competing Interests: Declarations Ethics approval and consent to participate The study was discussed, and the rectal swabbing was approved by the Research Screening and Ethical Clearance Committee of the College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda (003/2021/DRI). The study was performed in compliance with institutional guidelines for research on animals and an “informed consent named “Animal Health Survey Informed Consent Form” was obtained and signed from animal owners. All methods were performed in accordance with the relevant intitutaion guidelines and regulations. Consent for publication Not applicable. Competing interests The authors declare no competing interests., (© 2024. The Author(s).)

Self-rectifying memristive devices have emerged as promising contenders for low-power in-memory computing, presenting numerous advantages. However, characterizing the functional behavior of passive crossbar arrays incorporating these devices remains challenging due to sophisticated parasitic currents stemming from rich memristive dynamic behavior. Conventional methods using read margin assessments to evaluate functional behavior in passive crossbars are hindered by the voltage divider effect from the pull-up resistor. In this study, we propose a novel performance metric, Δ SC, harnessing sneak path currents to assess functional behavior. Through the application of a pair of negative rectification factors, RF n, L and RF n, H , we comprehensively delineate dynamic rectification behavior in both positive and negative bias regimes, as well as in low-resistance state and high-resistance state, deviating from conventional metrics such as on/off ratios, nonlinearity, and rectifying factors. Notably, Δ SC provides a quantitative evaluation of the interaction between sneak path currents and read margin, demonstrating its efficacy and addressing a pivotal research gap in the field. For instance, employing self-rectifying BiFeO 3 memristive cells featuring RF n, L = 1.22E3 and RF n, H = 9.27, we showcase the successful functional performance of a passive crossbar array, achieving Δ SC < 2.19E-2, while ensuring a read margin > 0., (© 2024. The Author(s).)

Today, there is a continuous worldwide battle against antimicrobial resistance (AMR) and that includes vancomycin-resistant enterococci (VRE). Methods that can adequately and quickly detect transmission chains in outbreaks are needed to trace and manage this problem fast and cost-effectively. In this study, DNA-microarray-based technology was developed for this purpose. It commenced with the bioinformatic design of specific oligonucleotide sequences to obtain amplification primers and hybridization probes. Microarrays were manufactured using these synthesized oligonucleotides. A highly parallel and stringent labeling and hybridization protocol was developed and employed using isolated genomic DNA from previously sequenced (referenced) clinical VRE strains for optimal sensitivity and specificity. Microarray results showed the detection of virulence, resistance, and species-specific genes in the VRE strains. Theoretical predictions of the microarray results were also derived from the sequences of the same VRE strain and were compared to array results while optimizing protocols until the microarray result and theoretical predictions were a match. The study concludes that DNA microarray technology can be used to quickly, accurately, and economically detect specifically and massively parallel target genes in enterococci.

In the present study, the presence of the Enterobacterales, Staphylococcus spp., Mammaliicoccus spp., and Enterococcus spp. in cloacal samples of nestling ospreys (Pandion haliaetus), a fish-eating specialist, from Mono Lake, California, USA was examined by a multiphasic approach, including antimicrobial and biocide susceptibility testing, genotyping, and whole genome sequencing of selected isolates. The most commonly detected species was Escherichia coli, followed by Mammaliicoccus sciuri, Staphylococcus delphini, Enterococcus faecalis, Enterococcus faecium, Hafnia alvei, Klebsiella pneumoniae, Citrobacter braakii and single isolates of Edwardsiella tarda, Edwardsiella albertii, Klebsiella aerogenes, Plesiomonas shigelloides and Staphylococcus pseudintermedius. Multi-drug resistance (MDR) was observed in two E. coli isolates and in an Enterococcus faecium isolate. The MDR blaCTX-M-55-positive E. coli belonged to the pandemic clone ST58. The results of the present study suggest that nestling ospreys are exposed to MDR bacteria, possibly through the ingestion of contaminated fish. Ospreys may be good biosentinels for the presence of these microorganisms and antibiotic resistance in the local environment and the risk for other wildlife, livestock and humans., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Loncaric et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

This work reports on an in vivo Raman-based endoscopy system, invaScope, enabling Raman measurements of healthy and tumor bladder tissue during an endoscopic procedure in the operating theatre. The presented study outlines the progression from the initial concept (validated through previously performed ex vivo studies) to the approval and implementation of a clinical investigational device according to the requirement within the framework of the European Medical Device Regulation (MDR2017/745). The study's primary objective was to employ the invaScope Raman system within the bladder, capturing in vivo spectroscopic Raman data followed by standard histo- and cytopathological examinations of urological tissue (considered the gold standard). The collected data were analyzed and correlated with histopathological findings post-procedure. Additionally, the study aimed to assess the feasibility of using diagnostic equipment, probes, and software for application in a clinical setting, evaluating usability aspects that are important during surgical procedures. This research represents a pivotal step toward advancing Raman spectroscopy for routine clinical use in characterizing bladder lesions.

This study explores memristor-based true random number generators (TRNGs) through their evolution and optimization, stemming from the concept of memristors first introduced by Leon Chua in 1971 and realized in 2008. We will consider memristor TRNGs coming from various entropy sources for producing high-quality random numbers. However, we must take into account both their strengths and weaknesses. The comparison with CMOS-based TRNGs will serve as an illustration that memristor TRNGs stand out due to their simpler circuits and lower power consumption- thus leading us into a case study involving electroless YMnO 3 (YMO) memristors as TRNG entropy sources that demonstrate good security properties by being able to produce unpredictable random numbers effectively. The end of our analysis sees us pinpointing challenges: post-processing algorithm optimization coupled with ensuring reliability over time for memristor-based TRNGs aimed at next-generation security applications.

Hybrid glasses derived from meltable metal-organic frameworks (MOFs) promise to combine the intriguing properties of MOFs with the universal processing ability of glasses. However, the shaping of hybrid glasses in their liquid state - in analogy to conventional glass processing - has been elusive thus far. Here, we present optical-quality glasses derived from the zeolitic imidazole framework ZIF-62 in the form of cm-scale objects. These allow for in-depth studies of optical transparency and refraction across the ultraviolet to near-infrared spectral range. Fundamental viscosity data are reported using a ball penetration technique, and subsequently employed to demonstrate the fabrication of micro-optical devices by thermal imprinting. Using 3D-printed fused silica templates, we show that concave as well as convex lens structures can be obtained at high precision by remelting the glass without trading-off on material quality. This enables multifunctional micro-optical devices combining the gas uptake and permeation ability of MOFs with the optical functionality of glass. As an example, we demonstrate the reversible change of optical refraction upon the incorporation of volatile guest molecules., (© 2024. The Author(s).)

Using magnetic nanoparticles (MNPs) for extracorporeal heating applications results in higher field strength and, therefore, particles of higher coercivity can be used, compared to intracorporeal applications. In this study, we report the synthesis and characterization of barium hexa-ferrite (BaFe 12 O 19 ) nanoparticles as potential particles for magnetic heating. Using a precipitation method followed by high-temperature calcination, we first studied the influence of varied synthesis parameters on the particles' properties. Second, the iron-to-barium ratio (Fe/Ba = r) was varied between 2 and 12. Vibrating sample magnetometry, scanning electron microscopy and X-ray diffraction were used for characterization. A considerable influence of the calcination temperature (T cal ) was found on the resulting magnetic properties, with a decrease in coercivity (H C ) from values above 370 kA/m for T cal = 800-1000 °C to H C = 45-70 kA/m for T cal = 1200 °C. We attribute this drop in H C mainly to the formation of entirely multi-domain particles at high T cal . For the varying Fe/Ba ratios, increasing amounts of BaFe 2 O 4 as an additional phase were detected by XRD in the small r (barium surplus) samples, lowering the particles' magnetization. A decrease in H C was found in the increased r samples. Crystal size ranged from 47 nm to 240 nm and large agglomerates were seen in SEM images. The reported particles, due to their controllable coercivity, can be a candidate for extracorporeal heating applications in the biomedical or biotechnological field.

Memristors, since their inception, have demonstrated remarkable characteristics, notably the exceptional reconfigurability of their memory. This study delves into electroforming-free YMnO3 (YMO)-based resistive switches, emphasizing the reconfigurable memory effect in multiferroic YMO thin films with metallically conducting electrodes and their pivotal role in achieving adaptable frequency responses in impedance circuits consisting of reconfigurable YMO-based resistive switches and no reconfigurable passive elements, e.g., inductors and capacitors. The multiferroic YMO possesses a network of charged domain walls which can be reconfigured by a time-dependent voltage applied between the metallically conducting electrodes. Through experimental demonstrations, this study scrutinizes the impedance response not only for individual switch devices but also for impedance circuitry based on YMO resistive switches in both low- and high-resistance states, interfacing with capacitors and inductors in parallel and series configurations. Scrutinized Nyquist plots visually capture the intricate dynamics of impedance circuitry, revealing the potential of electroforming-free YMO resistive switches in finely tuning frequency responses within impedance circuits. This adaptability, rooted in the unique properties of YMO, signifies a paradigm shift heralding the advent of advanced and flexible electronic technologies.

Staphylococcus argenteus is a recently described staphylococcal species that is related to Staphylococcus aureus but lacks the staphyloxanthin operon. It is able to acquire both resistance markers such as the SCC mec elements and mobile genetic elements carrying virulence-associated genes from S. aureus . This includes those encoding the Panton-Valentine leukocidin (PVL), which is associated mainly with severe and/or recurrent staphylococcal skin and soft tissue infections. Here, we describe the genome sequences of two PVL-positive, mecA -negative S. argenteus sequence type (ST) 2250 isolates from the United Arab Emirates in detail. The isolates were found in a dental clinic in the United Arab Emirates (UAE). Both were sequenced using Oxford Nanopore Technology (ONT). This demonstrated the presence of temperate bacteriophages in the staphylococcal genomes, including a PVL prophage. It was essentially identical to the published sequence of phiSa2wa&#95;st78 (GenBank NC&#95;055048), a PVL phage from an Australian S. aureus clonal complex (CC) 88 isolate. Besides the PVL prophage, one isolate carried another prophage and the second isolate carried two additional prophages, whereby the region between these two prophages was inverted. This "flipped" region comprised about 1,083,000 bp, or more than a third of the strain's genome, and it included the PVL prophage. Prophages were induced by Mitomycin C treatment and subjected to transmission electron microscopy (TEM). This yielded, in accordance to the sequencing results, one or, respectively, two distinct populations of icosahedral phages. It also showed prolate phages which presumptively might be identified as the PVL phage. This observation highlights the significance bacteriophages have as agents of horizontal gene transfer as well as the need for monitoring emerging staphylococcal strains, especially in cosmopolitan settings such as the UAE.

Objectives: The objective of the present study was to examine the diversity of Staphylococcus aureus from mastitis milk samples of cows in Rwanda., Methods: A total of 1080 quarter milk samples from 279 dairy cows were collected in 80 different farms from all five provinces of Rwanda. In total, 135 S. aureus isolates were obtained and subjected to genotyping (spa typing, DNA microarray, whole-genome sequencing (WGS)), antimicrobial susceptibility testing (AST) and phenotypic profiling by Fourier Transform Infrared (FTIR) spectroscopy (including capsular serotyping)., Results: Resistance to penicillin and/or tetracycline was most frequently observed. Ten sequence types (STs) (ST1, ST151, ST152, ST5477, ST700, ST7110, ST7983, ST7984, ST8320, ST97) belonging to seven clonal complexes (CCs) (CC1, CC130, CC152, CC3591, CC3666, CC705, CC97) were detected. The Panton-Valentine leukocidin (PVL) genes (lukF-PV/lukS-PV), the bovine leukocidin genes (lukM/lukF-P83) and the human and bovine toxic shock syndrome toxin gene tst-1 variants were detected. FTIR-based capsular serotyping showed CC-specific differences. Most CC97 (cap5 allele) isolates were primarily nonencapsulated (82%), whereas isolates of CC3591 and CC3666 (cap8 allele) were mostly encapsulated (86.4% and 57.8%, respectively). Our results underline the widespread global distribution of cattle-adapted CC97., Conclusion: The presence of CC3591 and CC3666 in bovine mastitis suggests an important role in cattle health and dairy production in Rwanda. The results of the present study support the need for a rigorous One-Health Surveillance program of the bovine-human interface., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Chronic rhinosinusitis (CRS) is a multifactorial infection of the nasal cavity and sinuses. In this study, nasal swabs from control donors (N = 128) and patients with CRS (N = 246) were analysed. Culture methods and metagenomics revealed no obvious differences in the composition of the bacterial communities between the two groups. However, at the functional level, several metabolic pathways were significantly enriched in the CRS group compared to the control group. Pathways such as carbohydrate transport metabolism, ATP synthesis, cofactors and vitamins, photosynthesis and transcription were highly enriched in CRS. In contrast, pathways related to lipid metabolism were more representative in the control microbiome. As S. aureus is one of the main species found in the nasal cavity, staphylococcal isolates from control and CRS samples were analysed by microarray and functional assays. Although no significant genetic differences were detected by microarray, S. aureus from CRS induced less cytotoxicity to lung cells and lower rates of glycolysis in host cells than control isolates. These results suggest the differential modulation of staphylococcal virulence by the environment created by other microorganisms and their interactions with host cells in control and CRS samples. These changes were reflected in the differential expression of cytokines and in the expression of Agr, the most important quorum-sensing regulator of virulence in S. aureus . In addition, the CRS isolates remained stable in their cytotoxicity, whereas the cytotoxic activity of S. aureus isolated from control subjects decreased over time during in vitro passage. These results suggest that host factors influence the virulence of S. aureus and promote its adaptation to the nasal environment during CRS.

One of the greatest challenges to the use of molecular methods for diagnostic purposes is the detection of target DNA that is present only in low concentrations. One major factor that negatively impacts accuracy, diagnostic sensitivity, and specificity is the sample matrix, which hinders the attainment of the required detection limit due to the presence of residual background DNA. To address this issue, various methods have been developed to enhance sensitivity through targeted pre-amplification of marker sequences. Diagnostic sensitivity to the single molecular level is critical, particularly when identifying bloodstream infections. In cases of clinically manifest sepsis, the concentration of bacteria in the blood may reach as low as one bacterial cell/CFU per mL of blood. Therefore, it is crucial to achieve the highest level of sensitivity for accurate detection. In the present study, we have established a method that fills the analytical gap between low concentrations of molecular markers and the minimum requirements for molecular testing. For this purpose, a sample preparation of whole blood samples with a directly downstream pre-amplification was developed, which amplifies specific species and resistance markers in a multiplex procedure. When applying pre-amplification techniques, the sensitivity of the pathogen detection in whole blood samples was up to 100 times higher than in non-pre-amplified samples. The method was tested with blood samples that were spiked with several Gram-positive and Gram-negative bacterial pathogens. By applying this method to artificial spiked blood samples, it was possible to demonstrate a sensitivity of 1 colony-forming unit (CFU) per millilitre of blood for S. aureus and E. faecium . A detection limit of 28 and 383 CFU per ml of blood was achieved for E. coli and K. pneumoniae , respectively. If the sensitivity is also confirmed for real clinical blood samples from septic patients, the novel technique can be used for pathogen detection without cultivation, which might help to accelerate diagnostics and, thus, to decrease sepsis mortality rates.

Staphylococcus aureus is a versatile pathogen that does not only occur in humans but also in various wild and domestic animals, including several avian species. When characterizing S. aureus isolates from waterfowl, isolates were identified as atypical CC133 by DNA microarray analysis. They differed from previously sequenced CC133 strains in the presence of the collagen adhesin gene cna ; some also showed a different capsule type and a deviant spa type. Thus, they were subjected to whole-genome sequencing. This revealed multiple insertions of large regions of DNA from other S. aureus lineages into a CC133-derived backbone genome. Three distinct strains were identified based on the size and extent of these inserts. One strain comprised two small inserts of foreign DNA up- and downstream of oriC ; one of about 7000 nt or 0.25% originated from CC692 and the other, at ca. 38,000 nt or 1.3% slightly larger one was of CC522 provenance. The second strain carried a larger CC692 insert (nearly 257,000 nt or 10% of the strain's genome), and its CC522-derived insert was also larger, at about 53,500 nt or 2% of the genome). The third strain carried an identical CC692-derived region (in which the same mutations were observed as in the second strain), but it had a considerably larger CC522-like insertion of about 167,000 nt or 5.9% of the genome. Both isolates of the first, and two out of four isolates of the second strain also harbored a hemolysin-beta-integrating prophage carrying "bird-specific" virulence factors, ornithine cyclodeaminase D0K6J8 and a putative protease D0K6J9. Furthermore, isolates had two different variants of SCC elements that lacked mecA/mecC genes. These findings highlight the role of horizontal gene transfer in the evolution of S. aureus facilitated by SCC elements, by phages, and by a yet undescribed mechanism for large-scale exchange of core genomic DNA.

Advanced glycation end products (AGEs) form extracellular crosslinking with collagenous proteins, which contributes to the development of diabetic complications. In this study, AGEs-related pentosidine (PENT) crosslinks-induced structural and biochemical changes are studied using multimodal multiphoton imaging, Raman spectroscopy and atomic force microscopy (AFM). Decellularized equine pericardium (EP) was glycated with four ribose concentrations ranging between 5 and 200 mM and monitored for up to 30 days. Two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) microscopic imaging probed elastin and collagen fibers, respectively. The glycated EP showed a decrease in the SHG intensities associated with loss of non-centrosymmetry of collagen and an increase of TPEF intensities associated with PENT crosslinks upon glycation. TPEF signals from elastin fibers were unaffected. A three-dimensional reconstruction with SHG + TPEF z-stack images visualized the distribution of collagen and elastin within the EP volume matrix. In addition, Raman spectroscopy (RS) detected changes in collagen-related bands and discriminated glycated from untreated EP. Furthermore, AFM scans showed that the roughness increases and the D-unit structure of fibers remained unchanged during glycation. The PENT crosslinked-induced changes are discussed in the context of previous studies of glutaraldehyde- and genipin-induced crosslinking and collagenase-induced digestion of collagen. We conclude that TPEF, SHG, RS, and AFM are effective, label-free, and non-destructive methods to investigate glycated tissues, differentiate crosslinking processes, and characterize general collagen-associated and disease-related changes, in particular by their RS fingerprints., (© 2023. The Author(s).)

Mycoplasmopsis (M.) bovis, the agent of mastitis, pneumonia, and arthritis in cattle, harbors a small genome of approximately 1 Mbp. Combining data from Illumina and Nanopore technologies, we sequenced and assembled the genomes of 35 European strains and isolate DL422&#95;88 from Cuba. While the high proportion of repetitive structures in M. bovis genomes represent a particular challenge, implementation of our own pipeline Mycovista (available on GitHub www.github.com/sandraTriebel/mycovista ) in a hybrid approach enabled contiguous assembly of the genomes and, consequently, improved annotation rates considerably. To put our European strain panel in a global context, we analyzed the new genome sequences together with 175 genome assemblies from public databases. Construction of a phylogenetic tree based on core genes of these 219 strains revealed a clustering pattern according to geographical origin, with European isolates positioned on clades 4 and 5. Genomic data allowing assignment of strains to tissue specificity or certain disease manifestations could not be identified. Seven strains isolated from cattle with systemic circular condition (SCC), still a largely unknown manifestation of M. bovis disease, were located on both clades 4 and 5. Pairwise association analysis revealed 108 genomic elements associated with a particular clade of the phylogenetic tree. Further analyzing these hits, 25 genes are functionally annotated and could be linked to a M. bovis protein, e.g. various proteases and nucleases, as well as ten variable surface lipoproteins (Vsps) and other surface proteins. These clade-specific genes could serve as useful markers in epidemiological and clinical surveys., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Bovine mastitis is a common disease of dairy cattle causing major economic losses due to reduced yield and poor quality of milk worldwide. The current investigation aimed to gain insight into the genetic diversity, antimicrobial resistance profiles and virulence associated factors of Staphylococcus ( S. ) aureus isolated from clinical bovine mastitis in dairy farms in Thuringia, Germany., Methods: Forty Staphylococcus aureus isolates collected from clinical bovine mastitis cases from 17 Thuringian dairy farms were phenotyped and genetically characterized using whole genome sequencing., Results: Out of 40 S. aureus , 30 (75%) were confirmed as methicillin resistant isolates. The isolates showed elevated antimicrobial resistance against penicillin, tetracycline and oxacillin, i.e., 77.5, 77.5, and 75%, respectively. Lower resistance rates were found against moxifloxacin, ciprofloxacin, gentamicin and trimethoprim/sulfamethoxazole, i.e., 35, 35, 30, and 22.5%, respectively. While resistance against clindamycin and erythromycin was rarely found (5 and 2.5%, respectively). All isolates were susceptible to linezolid, teicoplanin, vancomycin, tigecycline, fosfomycin, fusidic acid and rifampicin. These isolates were further allocated into five different sequence types: ST398 ( n  = 31), ST1074 ( n  = 4), ST504 ( n  = 3), ST582 (CC15) ( n  = 1) and ST479 ( n  = 1). These isolates were also assigned to seven clusters with up to 100 SNP which has facilitated geographical mapping and epidemiological distribution in Thuringia. Strains belonging to ST398 were classified into clusters 1, 2, 3, 4 and 7. The isolates of ST504 were of cluster 5, those of ST1074 were belonging to cluster 6. Resistance genes bla Z, bla I and bla R associated with penicillin resistance were found in 32 (80%) strains, all except one were belonging to ST398. Methicillin resistance associated mec A was identified in 30 (96.8%) isolates of ST398. All tetracycline and erythromycin resistant isolates were of ST398, and all harbored both tet M and erm A. About 90.3% of tetracycline resistant isolates assigned to ST398 were also carrying tet K gene. The point mutations par C&#95;S80F, gyr A&#95;S84L and par C&#95;S80Y in gyr A and par C associated with quinolone resistance were found in all phenotypically resistant isolates to ciprofloxacin and moxifloxacin ( n  = 14). Sixty-eight virulence genes were identified among isolates. Both luk D/E and lukM /F-PV-P83 were identified in 22.5% of isolates, all were non-ST398., Conclusion: In this study, ST398 had the highest potential to cause disease and had a massive prevalence in bovine mastitis cases. Five different sequence types and seven clusters were identified in the federal state of Thuringia. The circulation of some clusters in the same region over several years shows the persistence of cluster-associated infection despite the intensive veterinary care. On the other hand, some regions had different clusters at the same year or in different consecutive years. Different sequence types and associated different clusters of S. aureus were geographically widely distributed among dairy farms in Thuringia. The findings of this study show that various clusters have the potential to spread over a large geographical scale. The detection of LA-MRSA on dairy farms, which is known for cabapility to widely spread among different groups of animals, humans and their environment urges for the implementation of national wide strategic programs. The identification of CA-MRSA among the isolates such as ST398 poses a significant risk for the transmission of such strains between animals and humans on dairy farms., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Moawad, El-Adawy, Linde, Jost, Tanja, Katja, Karsten, Neubauer, Monecke and Tomaso.)