Background/objectives: Growing evidence suggests that the gut-brain axis influences brain function, particularly the role of intestinal microbiota in modulating cognitive processes. Probiotics may alter brain function and behavior by modulating gut microbiota, with implications for neurodegenerative diseases like Alzheimer's disease (AD). The purpose of this review is to systematically review the current literature exploring the effects of probiotic supplementation on gut microbiota and cognitive function in AD and mild cognitive impairment (MCI).
View Article and Find Full Text PDFObjectives: This study aims to elucidate the genomic dynamics driving the emergence of antimicrobial resistance (AMR), with a specific focus on the interplay between AMR and antimicrobial usage.
Methods: We conducted a comprehensive analysis using a ST239 methicillin-resistant Staphylococcus aureus (MRSA) dataset over a continuous 12-year period from a single hospital. Genomic analyses were performed tracking the changes in MRSA populations, particularly the emergence of reduced vancomycin susceptibility, and assessing the impact of glycopeptide use on these emergence events.
Alzheimer's disease (AD) is a complex neurodegenerative disorder characterized by progressive cognitive decline and memory impairment. Many possible factors might contribute to the development of AD, including amyloid peptide and tau deposition, but more recent evidence suggests that neuroinflammation may also play an-at least partial-role in its pathogenesis. In recent years, emerging research has explored the possible involvement of external, invading pathogens in starting or accelerating the neuroinflammatory processes in AD.
View Article and Find Full Text PDFThe majority of large multiresistance plasmids of Staphylococcus aureus utilise a RepA_N-type replication initiation protein, the expression of which is regulated by a small antisense RNA (RNAI) that overlaps the rep mRNA leader. The pSK41/pGO1-family of conjugative plasmids additionally possess a small (86 codon) divergently transcribed ORF (orf86) located upstream of the rep locus. The product of pSK41 orf86 was predicted to have a helix-turn-helix motif suggestive of a likely function in transcriptional repression.
View Article and Find Full Text PDFLong-duration spaceflight can have adverse effects on human health. One of the most common ocular conditions experienced by astronauts is dry eye disease (DED). Symptoms of DED include feelings of eye irritation, eye strain, foreign body sensation and blurred vision.
View Article and Find Full Text PDFHidradenitis Suppurativa is a chronic inflammatory disease of which the pathogenesis is incompletely understood. Dermal fibroblasts have been previously identified as a major source of inflammatory cytokines, however information pertaining to the characteristics of subpopulations of fibroblasts in HS remains unexplored. Using in silico-deconvolution of whole-tissue RNAseq, Nanostring gene expression panels and confirmatory immunohistochemistry we identified fibroblast subpopulations in HS tissue and their relationship to disease severity and lesion morphology.
View Article and Find Full Text PDFThere is an increasing use of non-medicated wound dressing with claims of irreversible bacterial binding. Most of the data are from in vitro models which lack clinical relevance. This study employed a range of in vitro experiments to address this gap and we complemented our experimental designs with in vivo observations using dressings obtained from patients with diabetes-related foot ulcers.
View Article and Find Full Text PDFIn this proof-of-concept study of twenty participants, we sought to determine if a DACC (Dialkylcarbamoyl chloride)-coated mesh dressing demonstrates an ability to adhere biofilm when placed on Diabetes Related Foot Ulcers (DRFUs) with chronic infection. The study also sought to determine if removal of the DACC-coated mesh dressings contributes to reducing the total number of bacteria in DRFUs, by exploring the total microbial loads, microbial community composition, and diversity. Standard of care was provided in addition to the application of DACC or DACC hydrogel every three days for a total of two weeks.
View Article and Find Full Text PDFOsteomyelitis in the feet of persons with diabetes is clinically challenging and is associated with high rates of amputation. In this study RNA-sequencing was employed to explore microbial metatranscriptomes with a view to understand the relative activity and functions of the pathogen/s responsible for diabetes foot osteomyelitis (DFO). We obtained 25 intraoperative bone specimens from persons with confirmed DFO, observing that spp.
View Article and Find Full Text PDFThe segregation of prokaryotic plasmids typically requires a centromere-like site and two proteins, a centromere-binding protein (CBP) and an NTPase. By contrast, a single 245 residue Par protein mediates partition of the prototypical staphylococcal multiresistance plasmid pSK1 in the absence of an identifiable NTPase component. To gain insight into centromere binding by pSK1 Par and its segregation function we performed structural, biochemical and in vivo studies.
View Article and Find Full Text PDFCurrently available methods for the laboratory investigation of Legionella pneumophila outbreaks require organism culture. The ability to sequence L. pneumophila directly from clinical samples would significantly reduce delays.
View Article and Find Full Text PDFCellular mechanisms and/or microbiological interactions which contribute to chronic diabetes related foot ulcers (DRFUs) were explored using serially collected tissue specimens from chronic DRFUs and control healthy foot skin. Total RNA was isolated for next-generation sequencing. We found differentially expressed genes (DEGs) and enriched hallmark gene ontology biological processes upregulated in chronic DRFUs which primarily functioned in the host immune response including: (i) Inflammatory response; (ii) TNF signalling via NFKB; (iii) IL6 JAK-STAT3 signalling; (iv) IL2 STAT5 signalling and (v) Reactive oxygen species.
View Article and Find Full Text PDFVirtually all diabetes-related foot ulcers (DRFUs) will become colonized by microorganisms that may increase the risk of developing an infection. The reasons why some ulcerations develop acute clinical infections (AI-DRFUs) whilst others develop chronic infection (CI-DRFUs) and the preceding host-microbe interactions in vivo remain largely unknown. Establishing that acute and chronic infections are distinct processes requires demonstrating that these are two different strategies employed by microbes when interacting with a host.
View Article and Find Full Text PDFA topical desiccating wound agent containing methanesulfonic acid, dimethylsulfoxide and amorphous silica was evaluated in three in vitro models for its efficacy against biofilms produced by (ATCC-15442) and (ATCC-6538). The in vitro biofilm models used were; the MBEC Assay, Centre for Disease Control (CDC) Biofilm Reactor and a Semi-solid biofilm model. A 30-s exposure of a topical wound desiccating agent was used in each model.
View Article and Find Full Text PDFMethicillin-resistant Staphylococcus sciuri (MRSS) strain C2865 from a stranded dog in Nigeria was trimethoprim (TMP) resistant but lacked formerly described staphylococcal TMP-resistant dihydrofolate reductase genes (). Whole-genome sequencing, comparative genomics, and pan-genome analyses were pursued to unveil the molecular bases for TMP resistance via resistome and mobilome profiling. MRSS C2865 comprised a species subcluster and positioned just above the intraspecies boundary.
View Article and Find Full Text PDFDiabetic foot infections (DFIs) are a major cause of hospitalization and can lead to lower extremity amputation. In this pilot study, we used a multiomics approach to explore the host-microbe complex within DFIs. We observed minimal differences in the overall microbial composition between PEDIS infection severities, however Staphylococcus aureus and Streptococcus genera were abundant and highly active in most mild to moderate DFIs.
View Article and Find Full Text PDFThis proof-of-concept study sought to determine the effects of standard of care (SOC) and a topically applied concentrated surfactant gel (SG) on the total microbial load, community composition, and community diversity in non-healing diabetic foot ulcers (DFUs) with chronic biofilm infections. SOC was provided in addition to a topical concentrated SG, applied every 2 days for 6 weeks. Wound swabs were obtained from the base of ulcers at baseline (week 0), week 1, mid-point (week 3), and end of treatment (week 6).
View Article and Find Full Text PDFThis study compares two vs six weeks of topical antimicrobial therapy with Cadexomer Iodine in patients with diabetic foot ulcers (DFUs) complicated by chronic biofilm infections. Patients with non-healing DFUs with suspected chronic biofilm infections were eligible for enrolment. Patients were randomised to receive either two or six weeks of treatment with topical Cadexomer Iodine.
View Article and Find Full Text PDFMultiple approaches were employed to detect pathogens from bone margins associated with Diabetic Foot Osteomyelitis (DFO). Intra-operative bone specimens of 14 consecutive subjects with suspected DFO were collected over a six-month study period from Liverpool Hospital. Infected bone and a proximal bone margins presumed to be 'clean/non-infected' were collected.
View Article and Find Full Text PDFis a significant human pathogen whose evolution and adaptation have been shaped in part by mobile genetic elements (MGEs), facilitating the global spread of extensive antimicrobial resistance. However, our understanding of the evolutionary dynamics surrounding MGEs, in particular, how changes in the structure of multidrug resistance (MDR) plasmids may influence important staphylococcal phenotypes, is incomplete. Here, we undertook a population and functional genomics study of 212 methicillin-resistant (MRSA) sequence type 239 (ST239) isolates collected over 32 years to explore the evolution of the pSK1 family of MDR plasmids, illustrating how these plasmids have coevolved with and contributed to the successful adaptation of this persistent MRSA lineage.
View Article and Find Full Text PDFStrains of , and to a lesser extent other staphylococcal species, are a significant cause of morbidity and mortality. An important factor in the notoriety of these organisms stems from their frequent resistance to many antimicrobial agents used for chemotherapy. This review catalogues the variety of mobile genetic elements that have been identified in staphylococci, with a primary focus on those associated with the recruitment and spread of antimicrobial resistance genes.
View Article and Find Full Text PDFAnn Clin Microbiol Antimicrob
October 2018
Introduction: During clinical use, gastrointestinal endoscopes are grossly contaminated with patient's native flora. These endoscopes undergo reprocessing to prevent infectious transmission upon future use. Endoscopy-associated infections and outbreaks have been reported, with a recent focus on the transmission of multi-drug resistant organisms.
View Article and Find Full Text PDFStrains of bacteria resistant to antibiotics, particularly those that are multiresistant, are an increasing major health care problem around the world. It is now abundantly clear that both Gram-negative and Gram-positive bacteria are able to meet the evolutionary challenge of combating antimicrobial chemotherapy, often by acquiring preexisting resistance determinants from the bacterial gene pool. This is achieved through the concerted activities of mobile genetic elements able to move within or between DNA molecules, which include insertion sequences, transposons, and gene cassettes/integrons, and those that are able to transfer between bacterial cells, such as plasmids and integrative conjugative elements.
View Article and Find Full Text PDFOBJECTIVETo describe the transmission dynamics of the emergence and persistence of vanA vancomycin-resistant enterococcus (VRE) in an intensive care unit (ICU) using whole-genome sequencing of patient and environmental isolates.DESIGNRetrospective cohort study.SETTINGICU in a tertiary referral center.
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