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Background: Streptococcus uberis is one of the main causative agents of ovine mastitis, however little is known about this global, environmental pathogen and its genomic mechanisms of disease. In this study, we performed genomic analysis on 46 S. uberis isolates collected from mastitis-infected sheep in Sardinia (Italy). Results: Genomes were assigned into lineage clusters using PopPUNK, which found 27 distinct isolate clusters, indicating considerable genetic variability consistent with environmental isolates. Geographic trends were identified including regional linkage of several isolate clusters. Multi-locus Sequence Typing (MLST) performed poorly and provided no new insights. Genomes were then screened for antimicrobial resistance genes, which were compared to phenotypic resistance profiles. Isolates showed consistent phenotypic resistance to aminoglycosides with variable resistance to novobiocin and tetracycline. In general, identification of antimicrobial resistance genes did not correlate with phenotypic resistance profiles, indicating unknown genetic determinants. A multi-antimicrobial resistance cassette (aminoglycoside, lincosamide and streptogramin) was identified in the chromosome of three genomes, flanked by vestigial phage recombinases. This locus appears to have spread horizontally within discrete S. uberis populations within a 40 km radius (Sassari region). Genomes were screened for putative virulence factors, which identified 16 genes conserved between sheep and cow isolates, with no host-specific genes shared uniformly across all host-specific isolates. Pangenomic analysis was then performed to identify core genes which were putatively surface-exposed, for identification of potential vaccine targets. As all genomes encoded sortase, core genes were screened for the sortase cleavage motif. Of the 1445 core S. uberis genes, 64 were putative sortase substrates and were predominantly adhesins, permeases and peptidases, consistent with compounds found within ruminant milk such as xanthine, fibronectin and lactoferrin. Conclusions: This study demonstrated the importance of whole genome sequencing for surveillance of S. uberis and tracking horizontal acquisition of antimicrobial resistance genes, as well as providing insight into genetic determinants of disease, which cannot be inferred from the MLST schemes. Future mastitis surveillance should be informed by genomic analysis. [ABSTRACT FROM AUTHOR]

To improve symptoms and reduce poor outcomes related to heart failure (HF), international guidelines recommend cardiac rehabilitation (CR), particularly for those with a reduced ejection fraction. Unfortunately, patient adherence to rehabilitation programs remains suboptimal, with dropouts ranging from 15.4 to 63.3%. An innovative and promising intervention that could improve adherence to rehabilitation is virtual reality (VR). This study aims to evaluate the effects of VR in patients with HF who undergo CR using this technology in terms of adherence (primary outcome), functional capacity, perceived exertion, angina, quality of life, heart rate, oxygen saturation, blood pressure, maximum oxygen uptake, minute ventilation/carbon dioxide production slope, oxygen pulse, blood values of NT-proBNP and HF related rehospitalization rates (secondary outcomes). A randomized controlled trial will be conducted in a sample of 80 patients referred to CR. Participants will be enrolled in a cardiological rehabilitation unit of a large university hospital in Italy and randomized (1:1) to the experimental intervention consisting of CR performed with high-quality immersive VR with PICO 4® Head Mounted Display headset and TREADMILL XR® software (Arm 1) or standard CR (Arm 2). Patients, according to guidelines, will perform 30-min of CR sessions with moderate intensity, twice a week for one month. Significant improvements in primary and secondary outcomes are expected in patients in the intervention group. If proven to be effective, VR could be an innovative, safe, and easy digital health intervention to improve adherence to CR in patients with HF, as well as important clinical outcomes. [ABSTRACT FROM AUTHOR]