Journal of neurotrauma
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Journal of neurotrauma · Jan 2019
Relative Deficiency of Plasma ADAMTS13 Activity and Elevation of Human Neutrophil Peptides in Patients with Traumatic Brain Injury.
Traumatic microvascular injury (tMVI) is a universal endophenotype of traumatic brain injury (TBI) that is responsible for significant neurological morbidity and mortality. The mechanism underlying tMVI is not fully understood. The present study aims to determine plasma levels of von Willebrand factor (VWF), a disintegrin and metalloprotease with thrombospondin type 1 repeats (ADAMTS) 13 activity, and human neutrophil peptides (HNP) 1-3 and to correlate these biomarkers with functional outcomes after moderate-severe TBI. ⋯ This resulted in a dramatic reduction in the ratio of ADAMTS13 activity to VWFAg or ADAMTS13 to VWFAc in all 5 post-TBI days. Cluster analysis demonstrated that high median plasma levels of VWFAg and HNP1-3 were observed in the cluster with a high mortality rate. These results demonstrate that a relative deficiency of plasma ADAMTS13 activity, resulting from activation of neutrophils and endothelium, may contribute to the formation of microvascular thrombosis and mortality after moderate-severe TBI.
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Journal of neurotrauma · Jan 2019
White Matter Anisotropy for Impact Simulation and Response Sampling in Traumatic Brain Injury.
Advanced neuroimaging provides new opportunities to enhance head injury models, including the incorporation of white matter (WM) structural anisotropy. Information from high-resolution neuroimaging, however, usually has to be "down-sampled" to match a typically coarse brain mesh. To understand how this mesh-image resolution mismatch affects impact simulation and subsequent response sampling, we compared three competing anisotropy implementations (using either voxels, tractography, or a multiscale submodeling) and two response sampling strategies (element-wise or tractography-based, using brain mesh or neuroimaging for region segmentation, respectively). ⋯ Brain strain responses were also parametrically found to be closer to that from minimum fiber reinforcement, consistent with the fact that the majority of WM had a rather high degree of fiber dispersion. Finally, the upgraded Worcester Head Injury Model incorporating WM anisotropy was successfully re-validated against cadaveric impacts and an in vivo head rotation ("good" to "excellent" validation with an average Correlation Analysis score of 0.437 and 0.509, respectively). These investigations may facilitate further continual development of head injury models to better study traumatic brain injury.
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Journal of neurotrauma · Jan 2019
Acute Inflammatory Biomarker Responses to Diffuse Traumatic Brain Injury in the Rat Monitored by a Novel Microdialysis Technique.
Neuroinflammation is a major contributor to the progressive brain injury process induced by traumatic brain injury (TBI), and may play an important role in the pathophysiology of axonal injury. The immediate neuroinflammatory cascade cannot be characterized in the human setting. Therefore, we used the midline fluid percussion injury model of diffuse TBI in rats and a novel microdialysis (MD) method providing stable diffusion-driven biomarker sampling. ⋯ Therefore, diffuse TBI was associated with an increased level of 18 of the 27 inflammatory biomarkers at one through six time points, during the observation period whereas the remaining 9 biomarkers were unaltered. The study shows that diffuse TBI induces an acute increase in a number of inflammatory biomarkers. The novel MD technique provides stable MD sampling suitable for further studies on the early neuroinflammatory cascade in TBI.