Biology subjects

Edwards, D. J.

Publications and source records attributed to Edwards, D. J..

3 recordsLinked to original sources

bioRxiv2017

Individual level reliability of PAS-induced neural plasticity

ObjectiveWe assessed the individual level reliability of neural plasticity changes induced by paired associative stimulation (PAS), which combines peripheral nerve stimulation with transcranial magnetic stimulation to induce short-term plastic changes in the brain.\n\nMethodsFor 5 consecutive weeks, motor evoked potentials (MEPs) of 8 healthy subjects were acquired every 10 minutes post-PAS intervention for a period of 60 minutes. The post-PAS MEPs were evaluated against base-line MEPs using permutation and Kolmogorov-Smirnov tests to determine whether the MEP magnitudes changed after PAS. Moreover, various sample sizes of the MEP data were used to deduce the minimum number of MEPs needed to reliably detect individual propensity to neural plasticity.\n\nResultsGroup analysis exhibited significant increase in post-PAS MEPs, confirming previous results. While high between-sessions variability was observed at individual level, data show that between 40 to 50 MEPs can reliably assess each subjects responsiveness to PAS. Subjects exhibited three different plasticity patterns: in the modulated hemisphere only, both hemispheres, or neither hemisphere.\n\nConclusionsPAS can reliably assess individual differences in neural plasticity.\n\nSignificanceA marker of individual plasticity may be useful to predict the effects of a motor rehabilitation, drug or other intervention to increase recovery of function after brain injury.\n\nHighlightsO_LIPaired associative stimulation (PAS) assesses neural plasticity non invasively.\nC_LIO_LIThe study shows how PAS can reliably determine individual differences in plasticity.\nC_LIO_LIPAS may be used to predict intervention outcome or individualize treatment dose.\nC_LI

neuroscience↗

bioRxiv2016

Gastrointestinal carriage is a major reservoir of K. pneumoniae infection in intensive care patients

BackgroundKlebsiella pneumoniae is an opportunistic pathogen and a leading cause of hospital-associated (HA) infections. Patients in intensive care units (ICUs) are particularly at risk, and outbreaks are frequently reported in ICUs. K. pneumoniae is also part of the healthy human microbiome, providing a potential reservoir for HA infection. However, the frequency of K. pneumoniae gut colonization and its contribution to HA infections are not well characterized.\n\nMethodsWe conducted one-year prospective cohort study of ICU patients. Participants (n=498) were screened for rectal and throat carriage of K. pneumoniae shortly after admission, and clinical information was extracted from hospital records.K. pneumoniae isolated from screening swabs and clinical diagnostic samples were characterized using whole genome sequencing. Genomic and epidemiological data were combined to identify likely transmission events.\n\nResults and ConclusionsK. pneumoniae carriage frequencies were estimated at 6% (95% CI, 3%-8%) amongst ICU patients admitted direct from the community, and 19% (95% CI, 14% - 51%) amongst those who had recent contact with healthcare. Gut colonisation on admission was significantly associated with subsequent K. pneumoniae infection (infection risk 16% vs 3%, OR=6.9, p<0.001), and genome data indicated a match between carriage and infection isolates in most patients. Five likely transmission chains were identified, resulting in six infections (12% of K. pneumoniae infections in ICU). In contrast, 49% of K. pneumoniae infections were caused by a strain that was unique to the patient, and 48% of patients with K. pneumoniae infections who participated in screening were positive for prior colonisation. These data confirm K. pneumoniae colonisation is a significant risk factor for subsequent infection in ICU, and indicate that half of all K. pneumoniae infections result from patients own microbiota. Screening for colonisation on admission could limit risk of infection in the colonised patient and others.

microbiology↗

bioRxiv2016

Genomic analysis of Mycobacterium tuberculosis reveals complex etiology of tuberculosis in Vietnam including frequent introduction and transmission of Beijing lineage and positive selection for EsxW Beijing variant

Introduction Introduction Accession codes AUTHOR CONTRIBUTIONS COMPETING FINANCIAL INTERESTS Online Methods References Tuberculosis (TB) is a leading cause of death from infectious disease and the global burden is now higher than at any point in history 1,2 Despite coordinated efforts to control TB transmission, the factors contributing to its successful spread remain poorly understood. Vietnam is identified as one of 30 high burden countries for TB and MDR-TB with an incidence of 137 TB cases per 100,000 individuals in 2015 2 Recent phylogenomic analyses of the causative agent Mycobacterium tuberculosis (Mtb) in other high-prevalence regions have provided insights into the complex processes underlying TB transmission ...

genomics↗