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  • Journal article
    De Simoni S, Grover PJ, Jenkins PO, Honeyfield L, Quest R, Scott G, Wilson WH, Majewska P, Waldman AD, Patel MC, Sharp DJet al., 2016,

    Disconnection between the default mode network and medial temporal lobes in post-traumatic amnesia

    , Brain, Vol: 139, Pages: 3137-3150, ISSN: 0006-8950

    Post-traumatic amnesia is very common immediately after traumatic brain injury. It is characterised by a confused, agitated state and a pronounced inability to encode new memories and sustain attention. Clinically, post-traumatic amnesia is an important predictor of functional outcome. However, despite its prevalence and functional importance, the pathophysiology of post-traumatic amnesia is not understood. Memory processing relies on limbic structures such as the hippocampus, parahippocampus and parts of the cingulate cortex. These structures are connected within an intrinsic connectivity network, the Default Mode Network. Interactions within the Default Mode Network can be assessed using resting state functional magnetic resonance imaging, which can be acquired in confused patients unable to perform tasks in the scanner. Here we used this approach to test the hypothesis that the mnemonic symptoms of post-traumatic amnesia are caused by functional disconnection within the Default Mode Network. We assessed whether the hippocampus and parahippocampus showed evidence of transient disconnection from cortical brain regions involved in memory processing. 19 traumatic brain injury patients were classified into post-traumatic amnesia and traumatic brain injury control groups, based on their performance on a paired associates learning task. Cognitive function was also assessed with a detailed neuropsychological test battery. Functional interactions between brain regions were investigated using resting-state functional magnetic resonance imaging. Together with impairments in associative memory patients in post-traumatic amnesia demonstrated impairments in information processing speed and spatial working memory. Patients in post-traumatic amnesia showed abnormal functional connectivity between the parahippocampal gyrus and posterior cingulate cortex. The strength of this functional connection correlated with both associative memory and information processing speed and normal

  • Journal article
    Bacigaluppi M, Russo GL, Peruzzotti-Jametti L, Rossi S, Sandrone S, Butti E, De Ceglia R, Bergamaschi A, Motta C, Gallizioli M, Studer V, Colombo E, Farina C, Comi G, Politi LS, Muzio L, Villani C, Invernizzi RW, Hermann DM, Centonze D, Martino Get al., 2016,

    Neural Stem Cell Transplantation Induces Stroke Recovery by Upregulating Glutamate Transporter GLT-1 in Astrocytes

    , JOURNAL OF NEUROSCIENCE, Vol: 36, Pages: 10529-10544, ISSN: 0270-6474
  • Journal article
    Miras AD, Herring R, Vuisrikala A, Shojaee-Moradi F, Jackson NC, Chandaria S, Jackson SN, Goldstone AP, Hakim N, Patel A, Umpleby AM, le Roux CWet al., 2016,

    Measurement of hepatic insulin sensitivity early after the bypass of the proximal small bowel in humans

    , Obesity Science & Practice, Vol: 3, Pages: 95-98, ISSN: 2055-2238

    Objective: Unlike gastric banding or sleeve gastrectomy procedures, intestinal bypass procedures, and the Roux-en-Y gastric bypass (RYGB) in particular, lead to rapid improvements in glycaemia early after surgery. The bypass of the proximal small bowel may have weight loss and even caloric restriction independent glucose-lowering properties on hepatic insulin sensitivity. In this first in humans mechanistic study, we examined this hypothesis by investigating the early effects of the duodeno-jejunal bypass liner (DJBL; GI Dynamics, USA) on the hepatic insulin sensitivity using the gold standard euglycaemic hyperinsulinaemic clamp methodology. Method: Seven patients with obesity underwent measurement of hepatic insulin sensitivity at baseline, one week after a low-calorie liquid diet and after a further one week following insertion of the DJBL whilst on the same diet.Results: DJBL did not improve the insulin sensitivity of hepatic glucose production (HGP) beyond the improvements achieved with caloric restriction. Conclusions: Caloric restriction may be the predominant driver of early increases in hepatic insulin sensitivity after the endoscopic bypass of the proximal small bowel. The same mechanism may be at play after RYGB and explain, at least in part, the rapid improvements in glycaemia.

  • Conference paper
    Record C, De Simoni S, Feeney C, Sharp D, Nicholas R, Raffel Jet al., 2016,

    Improved cerebral blood flow after natalizumab treatment in multiple sclerosis

    , 32nd Congress of the European-Committee-for-Treatment-and-Research-in-Multiple-Sclerosis (ECTRIMS), Publisher: SAGE Publications, Pages: 669-669, ISSN: 1352-4585
  • Conference paper
    Peress L, Violante IR, Scott G, Zimmerman K, Sharp D, Nicholas R, Raffel Jet al., 2016,

    Thalamic magnetic resonance spectroscopy in highly active multiple sclerosis

    , 32nd Congress of the European-Committee-for-Treatment-and-Research-in-Multiple-Sclerosis (ECTRIMS), Publisher: SAGE PUBLICATIONS LTD, Pages: 210-211, ISSN: 1352-4585
  • Conference paper
    Connell L, Daws R, Hampshire A, Nicholas R, Raffel Jet al., 2016,

    Validating a participant-led computerised cognitive battery in people with multiple sclerosis

    , 32nd Congress of the European-Committee-for-Treatment-and-Research-in-Multiple-Sclerosis (ECTRIMS), Publisher: SAGE PUBLICATIONS LTD, Pages: 140-141, ISSN: 1352-4585
  • Journal article
    O'Shea T, Feeney C, Wise R, Sharp D, Goldstone Aet al., 2016,

    Post-traumatic amnesia, but not acute CT findings is predictive of pituitary dysfunction following traumatic brain injury

    , IRISH JOURNAL OF MEDICAL SCIENCE, Vol: 185, Pages: 400-401, ISSN: 0021-1265
  • Journal article
    Sariaslan A, Sharp DJ, D'Onofrio BM, Larsson H, Fazel Set al., 2016,

    Long-Term Outcomes Associated with Traumatic Brain Injury in Childhood and Adolescence: A Nationwide Swedish Cohort Study of a Wide Range of Medical and Social Outcomes

    , PLOS Medicine, Vol: 13, ISSN: 1549-1277

    BACKGROUND: Traumatic brain injury (TBI) is the leading cause of disability and mortality in children and young adults worldwide. It remains unclear, however, how TBI in childhood and adolescence is associated with adult mortality, psychiatric morbidity, and social outcomes. METHODS AND FINDINGS: In a Swedish birth cohort between 1973 and 1985 of 1,143,470 individuals, we identified all those who had sustained at least one TBI (n = 104,290 or 9.1%) up to age 25 y and their unaffected siblings (n = 68,268) using patient registers. We subsequently assessed these individuals for the following outcomes using multiple national registries: disability pension, specialist diagnoses of psychiatric disorders and psychiatric inpatient hospitalisation, premature mortality (before age 41 y), low educational attainment (not having achieved secondary school qualifications), and receiving means-tested welfare benefits. We used logistic and Cox regression models to quantify the association between TBI and specified adverse outcomes on the individual level. We further estimated population attributable fractions (PAF) for each outcome measure. We also compared differentially exposed siblings to account for unobserved genetic and environmental confounding. In addition to relative risk estimates, we examined absolute risks by calculating prevalence and Kaplan-Meier estimates. In complementary analyses, we tested whether the findings were moderated by injury severity, recurrence, and age at first injury (ages 0-4, 5-9, 6-10, 15-19, and 20-24 y). TBI exposure was associated with elevated risks of impaired adult functioning across all outcome measures. After a median follow-up period of 8 y from age 26 y, we found that TBI contributed to absolute risks of over 10% for specialist diagnoses of psychiatric disorders and low educational attainment, approximately 5% for disability pension, and 2% for premature mortality. The highest relative risks, adjusted for sex, birth year, and birth order

  • Journal article
    Shamshiri EA, Tierney TM, Centeno M, St Pier K, Pressler RM, Sharp DJ, Perani S, Cross JH, Carmichael DWet al., 2016,

    Interictal activity is an important contributor to abnormal intrinsic network connectivity in paediatric focal epilepsy

    , Human Brain Mapping, ISSN: 1097-0193

    Patients with focal epilepsy have been shown to have reduced functional connectivity in intrinsic connectivity networks (ICNs), which has been related to neurocognitive development and outcome. However, the relationship between interictal epileptiform discharges (IEDs) and changes in ICNs remains unclear, with evidence both for and against their influence. EEG-fMRI data was obtained in 27 children with focal epilepsy (mixed localisation and aetiologies) and 17 controls. A natural stimulus task (cartoon blocks verses blocks where the subject was told "please wait") was used to enhance the connectivity within networks corresponding to ICNs while reducing potential confounds of vigilance and motion. Our primary hypothesis was that the functional connectivity within visual and attention networks would be reduced in patients with epilepsy. We further hypothesized that controlling for the effects of IEDs would increase the connectivity in the patient group. The key findings were: (1) Patients with mixed epileptic foci showed a common connectivity reduction in lateral visual and attentional networks compared with controls. (2) Having controlled for the effects of IEDs there were no connectivity differences between patients and controls. (3) A comparison within patients revealed reduced connectivity between the attentional network and basal ganglia associated with interictal epileptiform discharges. We also found that the task activations were reduced in epilepsy patients but that this was unrelated to IED occurrence. Unexpectedly, connectivity changes in ICNs were strongly associated with the transient effects of interictal epileptiform discharges. Interictal epileptiform discharges were shown to have a pervasive transient influence on the brain's functional organisation. Hum Brain Mapp, 2016. © 2016 Wiley Periodicals, Inc.

  • Journal article
    Matthews PM, Hampshire A, 2016,

    Clinical concepts emerging from fMRI functional connectomics

    , Neuron, Vol: 91, Pages: 511-528, ISSN: 0896-6273

    Recent advances in connectomics have led to a synthesis of perspectives regarding the brain's functional organization that reconciles classical concepts of localized specialization with an appreciation for properties that emerge from interactions across distributed functional networks. This provides a more comprehensive framework for understanding neural mechanisms of normal cognition and disease. Although fMRI has not become a routine clinical tool, research has already had important influences on clinical concepts guiding diagnosis and patient management. Here we review illustrative examples. Studies demonstrating the network plasticity possible in adults and the global consequences of even focal brain injuries or disease both have had substantial impact on modern concepts of disease evolution and expression. Applications of functional connectomics in studies of clinical populations are challenging traditional disease classifications and helping to clarify biological relationships between clinical syndromes (and thus also ways of extending indications for, or "re-purposing," current treatments). Large datasets from prospective, longitudinal studies promise to enable the discovery and validation of functional connectomic biomarkers with the potential to identify people at high risk of disease before clinical onset, at a time when treatments may be most effective. Studies of pain and consciousness have catalyzed reconsiderations of approaches to clinical management, but also have stimulated debate about the clinical meaningfulness of differences in internal perceptual or cognitive states inferred from functional connectomics or other physiological correlates. By way of a closing summary, we offer a personal view of immediate challenges and potential opportunities for clinically relevant applications of fMRI-based functional connectomics.

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

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