Journal of neurotrauma
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Journal of neurotrauma · Oct 2015
Mildly Reduced Brain Swelling and Improved Neurological Outcome in Aquaporin-4 Knockout Mice Following Controlled Cortical Impact Brain Injury.
Brain edema following traumatic brain injury (TBI) is associated with considerable morbidity and mortality. Prior indirect evidence has suggested the involvement of astrocyte water channel aquaporin-4 (AQP4) in the pathogenesis of TBI. Here, focal TBI was produced in wild type (AQP4(+/+)) and knockout (AQP4(-/-)) mice by controlled cortical impact injury (CCI) following craniotomy with dura intact (parameters: velocity 4.5 m/sec, depth 1.7 mm, dwell time 150 msec). ⋯ Transmission electron microscopy showed reduced astrocyte foot-process area in AQP4(-/-) mice at 24 h after CCI, with greater capillary lumen area. Blood-brain barrier disruption assessed by Evans blue dye extravasation was similar in AQP4(+/+) and AQP4(-/-) mice. We conclude that the mildly improved outcome in AQP4(-/-) mice following CCI results from reduced cytotoxic brain water accumulation, though concurrent cytotoxic and vasogenic mechanisms in TBI make the differences small compared to those seen in disorders where cytotoxic edema predominates.
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Journal of neurotrauma · Oct 2015
MEG Slow-wave Detection in Patients with Mild Traumatic Brain Injury and Ongoing Symptoms Correlated with Long-Term Neuropsychological Outcome.
Mild traumatic brain injury (mTBI) is common in the United States, accounting for as many as 75-80% of all TBIs. It is recognized as a significant public health concern, but there are ongoing controversies regarding the etiology of persistent symptoms post-mTBI. This constellation of nonspecific symptoms is referred to as postconcussive syndrome (PCS). ⋯ In addition, significant correlations between slow-wave activity on MEG and patterns of cognitive functioning were found in cortical areas, consistent with cognitive impairments on exams. Results provide more objective evidence that there may be subtle changes to the neurobiological integrity of the brain that can be detected by MEG. Further, these findings suggest that these abnormalities are associated with cognitive outcomes and may account, at least in part, for long-term PCS in those who have sustained an mTBI.
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Journal of neurotrauma · Oct 2015
Characterization of Subcellular Responses Induced by Exposure of Microbubbles to Astrocytes.
Blast traumatic brain injury (bTBI) has now been identified to associate with adverse health consequences among combat veterans. Post-traumatic stress disorder linked with explosive blasts, for example, may result from such brain injury. The fundamental questions about the nature, diagnosis, and long-term consequences of bTBI and causative relationship to post-traumatic stress disorder remain elusive, however. ⋯ Of the cells that survived the initial assault, several subcellular changes were monitored and determined using fluorescent microscopy, including cell viability, cytoskeletal reorganization, changes in focal adhesion, membrane permeability, and potential onset of apoptosis. While the astrocytes impacted by the shock wave only demonstrated essentially unaltered cellular behavior, the astrocytes exposed to microbubbles exhibited significantly different responses, including production of reactive oxygen species by collapse of microbubbles. In the present study, we characterized and report for the first time the altered biophysical and subcellular properties in astrocytes in response to exposure to the combination of shock waves and microbubbles.
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Journal of neurotrauma · Sep 2015
Nanoparticle Estrogen in Rat Spinal Cord Injury Elicits Rapid Anti-inflammatory Effects in Plasma, CSF and Tissue.
Persons with spinal cord injury (SCI) are in need of effective therapeutics. Estrogen (E2), as a steroid hormone, is a highly pleiotropic agent; with anti-inflammatory, anti-apoptotic, and neurotrophic properties, it is ideal for use in treatment of patients with SCI. Safety concerns around the use of high doses of E2 have limited clinical application, however. ⋯ E2 showed rapid anti-inflammatory effects, significantly reducing interleukin (IL)-6, GRO-KC, MCP-1, and S100β in one or all compartments. Numerous additional targets of rapid E2 modulation were identified including: leptin, MIP-1α, IL-4, IL-2, IL-10, IFNγ, tumor necrosis factor-α, etc. These data further elucidate the rapid anti-inflammatory effects E2 exerts in an acute rat SCI model, have identified additional targets of estrogen efficacy, and suggest nanoparticle delivered estrogen may provide a safe and efficacious treatment option in persons with acute SCI.
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Journal of neurotrauma · Sep 2015
Neurological recovery after traumatic cervical spinal cord injury is superior if surgical decompression and instrumented fusion are performed within 8 h versus 8-24 h after injury - a single centre experience.
A prospective study was performed to evaluate the impact of surgical decompression (SD) and instrumented fusion within 8 h versus 8-24 h after injury on neurological recovery after cervical traumatic spinal cord injury (tSCI) in patients operated on in the UMC Ljubljana, Slovenia. Only patients with the American Spinal Injury Association (ASIA) Impairment Scale (AIS) grades of A through C and with MRI-confirmed spinal cord compression were enrolled. The primary outcome was the change in AIS grade at the 6-month follow-up. ⋯ In a multivariate analysis, adjusted for the preoperative AIS grade and the degree of spinal canal compromise, the odds of an at least two-grade AIS improvement were at least 106% higher for patients in group 8 h than for patients in group 8-24 h (odds ratio=11.08, p=0.004). No statistically significant difference was found in the rate of perioperative complications, pneumonia, and the number of ventilator-dependent days or the mortality between the groups. Our results suggest that the patients with tSCI who undergo SD within 8 h after injury have superior neurological outcomes than patients who undergo SD 8-24 h after injury, without any increase in the rate of adverse effects.