Journal of neurotrauma
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Journal of neurotrauma · Jul 2018
Transient Receptor Potential Melastatin 4 Induces Astrocyte Swelling But Not Death after Diffuse Traumatic Brain Injury.
Traumatic brain injury (TBI) is a prevalent disease with significant costs. Although progress has been made in understanding the complex pathobiology of focal lesions associated with TBI, questions remain regarding the diffuse responses to injury. Expression of the transient receptor potential melastatin 4 (Trpm4) channel is linked to cytotoxic edema during hemorrhagic contusion expansion. ⋯ Correlative H&E assessments demonstrated little evidence of hippocampal damage, suggesting that Trpm4 expression by astrocytes does not precipitate cell death following diffuse TBI. Additionally, ultrastructural assessments showed Trpm4+ astrocytes exhibited twice the soma size compared with Trpm4- astrocytes, indicating that astrocyte swelling is associated with Trpm4 expression. This study provides a foundation for future investigations into the role of Trpm4 in astrocyte swelling and edema following diffuse TBI.
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Journal of neurotrauma · Jul 2018
Intracranial and Extracranial Injury Burden as Drivers of Impaired Cerebrovascular Reactivity in Traumatic Brain Injury.
Impaired cerebrovascular reactivity has been associated with outcome following traumatic brain injury (TBI), but it is unknown how it is affected by trauma severity. Thus, we aimed to explore the relationship between intracranial (IC) and extracranial (EC) injury burden and cerebrovascular reactivity in TBI patients. We retrospectively included critically ill TBI patients. ⋯ In summary, diffuse IC injury markers (thickness of SAH and the presence of a subdural hematoma) and APACHE II were most associated with dysfunction in cerebrovascular reactivity after TBI. Standard CT scoring systems and evidence of macroscopic parenchymal damage are poor predictors, implicating potentially both microscopic injury patterns and host response as drivers of dysfunctional cerebrovascular reactivity. Age remains a major variable associated with cerebrovascular reactivity.
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Journal of neurotrauma · Jul 2018
Observational StudyFeasibility of Telemetric Intracranial Pressure Monitoring in the Neuro Intensive Care Unit.
Intracranial pressure (ICP) monitoring is crucial in the management of acute neurosurgical conditions such as traumatic brain injury (TBI). However, pathological ICP may persist beyond the admission to the neuro intensive care unit (NICU). We investigated the feasibility of telemetric ICP monitoring in the NICU, as this technology provides the possibility of long-term ICP assessment beyond NICU discharge. ⋯ Therefore, telemetric ICP monitoring in an acute neurosurgical setting is feasible. Signal quality and stability are sufficient for clinical decision making based on mean ICP. The low sampling frequency (5 Hz) does not permit analysis of intracranial pulse wave morphology, but resolution is sufficient for calculation of derived indices such as the pressure reactivity index (PRx).
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Journal of neurotrauma · Jul 2018
Microglial Inflammasome Activation in Penetrating Ballistic-Like Brain Injury.
Penetrating traumatic brain injury (PTBI) is a significant cause of death and disability in the United States. Inflammasomes are one of the key regulators of the interleukin (IL)-1β mediated inflammatory responses after traumatic brain injury. However, the contribution of inflammasome signaling after PTBI has not been determined. ⋯ This expression of ASC in activated microglia persisted until 12 weeks following PBBI. This is the first report of inflammasome activation after PBBI. Our results demonstrate cell-specific patterns of inflammasome activation and pyroptosis predominantly in microglia, suggesting a sustained pro-inflammatory state following PBBI, thus offering a therapeutic target for this type of brain injury.
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Journal of neurotrauma · Jul 2018
Circular RNA Expression Profiles Alter Significantly after Traumatic Brain Injury in Rats.
Circular RNAs (circRNAs) are involved in a variety of diseases. However, the roles of circRNAs in traumatic brain injury (TBI) remain unknown. In this study, circRNA microarray was used to profile the altered circRNAs in the rat hippocampus following TBI. ⋯ CircRNA/microRNA (miRNA) interaction was predicted using Arraystar's homemade miRNA target prediction software based on TargetScan and miRanda. Thus, our studies have demonstrated altered circRNA expression pattern in the rat hippocampus after TBI, which may play important roles in post-TBI physiological and pathological processes. These findings may provide not only a new direction for studying the molecular mechanisms underlying TBI but also a new possibility for the treatment of TBI by modulating circRNAs.