Journal of neurotrauma
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Journal of neurotrauma · Aug 2016
Resuscitation With Valproic Acid Alters Inflammatory Genes in a Porcine Model of Combined Traumatic Brain Injury and Hemorrhagic Shock.
Traumatic brain injury and hemorrhagic shock (TBI+HS) elicit a complex inflammatory response that contributes to secondary brain injury. There is currently no proven pharmacologic treatment for TBI+HS, but modulation of the epigenome has been shown to be a promising strategy. The aim of this study was to investigate whether valproic acid (VPA), a histone deacetylase inhibitor, modulates the expression of cerebral inflammatory gene profiles in a large animal model of TBI+HS. ⋯ DAVID analysis indicated that a cluster of inflammatory pathways held the highest rank and gene enrichment score. Real-time PCR data confirmed that VPA significantly down-expressed genes that ultimately regulate nuclear factor-kB (NF-kB)-mediated production of cytokines, such as TYROBP, TREM2, CCR1, and IL-1β. This high-throughput analysis of cerebral gene expression shows that addition of VPA to the resuscitation protocol significantly modulates the expression of inflammatory pathways in a clinically realistic model of TBI+HS.
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Journal of neurotrauma · Aug 2016
Intravenous Administration of Simvastatin improves Cognitive Outcome following Severe Traumatic Brain Injury in Rats.
Simvastatin is a 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor commonly used to reduce serum cholesterol. The beneficial effects of oral simvastatin have been reported in pre-clinical models of traumatic brain injury (TBI). The current study was designed to evaluate the potential beneficial effects of simvastatin in a model of severe penetrating TBI using an intravenous (IV) route of administration. ⋯ Biomarker and cytokine analysis showed that IV simvastatin significantly reduced GFAP, interleukin (IL)-1α, and IL-17 serum levels by 4.0-, 2.6-, and 7.0-fold, respectively, at 4 h post-injury. Collectively, our results demonstrate that IV simvastatin provides significant protection against injury-induced cognitive dysfunction and reduces TBI-specific biomarker levels. Further research is warranted to identify the optimal dose and therapeutic window for IV delivery of simvastatin in models of severe TBI.
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Journal of neurotrauma · Aug 2016
Randomized Controlled Trial Multicenter StudyExternal validation of the IMPACT prognostic models for traumatic brain injury on the SyNAPSe trial.
Prediction models for patients with traumatic brain injury (TBI) are important for multiple reasons, including case-mix adjustment, trial design, and benchmarking for quality-of-care evaluation. Models should be generalizable and therefore require regular external validation. We aimed to validate the International Mission for Prognosis and Analysis of Clinical Trials in TBI (IMPACT) prognostic models for moderate and severe TBI in a recent randomized controlled trial. ⋯ This pattern of miscalibration was consistent across all three models. In a contemporary trial setting, the IMPACT models have reasonable discrimination if enrollment restrictions apply. Observed changes in outcome distribution necessitate updating of previously developed prognostic models.
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Journal of neurotrauma · Aug 2016
A Qualitative Study Exploring Factors Associated with Provider Adherence to Severe Pediatric Traumatic Brain Injury Guidelines.
Despite demonstrated improvement in patient outcomes with use of the Pediatric Traumatic Brain Injury (TBI) Guidelines (Guidelines), there are differential rates of adherence. Provider perspectives on barriers and facilitators to adherence have not been elucidated. This study aimed to identify and explore in depth the provider perspective on factors associated with adherence to the Guidelines using 19 focus groups with nurses and physicians who provided acute management for pediatric patients with TBI at five university-affiliated Level 1 trauma centers. ⋯ Provider training and experience, as well as attitudes towards other standardized care protocols, mirror the use and attitudes towards the Guidelines. Adherence was determined by the interaction of each of these guideline, institutional, and provider factors acting in concert. Incorporating provider perspectives on barriers and facilitators to adherence into hospital and team protocols is an important step toward improving adherence and ultimately patient outcomes.
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Journal of neurotrauma · Aug 2016
Outcome after Repetitive Mild Traumatic Brain Injury is Temporally Related to Glucose Uptake Profile at Time of Second Injury.
Repeated mild traumatic brain injury (rmTBI) results in worsened outcomes, compared with a single injury, but the mechanism of this phenomenon is unclear. We have previously shown that mild TBI in a rat lateral fluid percussion model results in globally depressed glucose uptake, with a peak depression at 24 h that resolves by 16 days post-injury. The current study investigated the outcomes of a repeat injury conducted at various times during this period of depressed glucose uptake. ⋯ The level of microglial and astrocytic activation also was associated with the timing of the second impact. Finally, rmTBI with latencies of 24 h and 5 days showed significant alterations in [(18)F]fluorodeoxyglucose uptake, compared with baseline scans. Therefore, we conclude that the state of the metabolic environment, as indicated by FDG-PET at the time of the repeat injury, significantly influences neurological outcomes.