Journal of neurotrauma
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Journal of neurotrauma · Dec 2017
Impaired baroreflex function during orthostatic challenge in patients after spinal cord injury.
The level of spinal cord injury (SCI) affects baroreflex regulation of blood pressure. While a parasympathetic cardiac chronotropic effect is preserved, baroreflex response could be impaired by sympathetic dysfunction under the SCI level. This study was aimed to evaluate the baroreflex function in SCI patients by the analysis of causal interaction between systolic blood pressure (SBP) and inter-beat intervals (IBI). ⋯ In conclusion, baroreflex dysfunction in SCI patients was detected using causal analysis methods during orthostatic challenge only. Baroreflex dysfunction is probably an important mechanism of the more expressed blood pressure decrease associated with CSCI. The severity of autonomic dysfunction was related to SCI level.
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Journal of neurotrauma · Dec 2017
Changes in Pressure, Hemodynamics and Metabolism Within the Spinal Cord During the First 7-days After Injury Using a Porcine Model.
Traumatic spinal cord injury (SCI) triggers many perturbations within the injured cord, such as decreased perfusion, reduced tissue oxygenation, increased hydrostatic pressure, and disrupted bioenergetics. While much attention is directed to neuroprotective interventions that might alleviate these early pathophysiologic responses to traumatic injury, the temporo-spatial characteristics of these responses within the injured cord are not well documented. In this study, we utilized our Yucatan mini-pig model of traumatic SCI to characterize intraparenchymal hemodynamic and metabolic changes within the spinal cord for 1 week post-injury. ⋯ Taken together, traumatic SCI resulted in an expanding area of ischemia/hypoxia, with ongoing physiological perturbations sustained out to 7 days post-injury. This suggests that our clinical practice of hemodynamically supporting patients out to 7 days post-injury may fail to address persistent ischemia within the injured cord. A detailed understanding of these pathophysiological mechanisms after SCI is essential to promote best practices for acute SCI patients.
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Journal of neurotrauma · Dec 2017
Observational StudyImpact of Blood Pressure, Lesion level and Physical Activity on Aortic Augmentation Index in Persons with SCI.
Individuals with chronic spinal cord injury (SCI) are at a heightened risk of cardiovascular disease (CVD) resulting from autonomic nervous system dysfunction, physical inactivity, and increased inflammatory processes. Arterial stiffness (AS) is recognized as an independent risk factor for CVD and, specifically, pulse wave analysis (PWA) has proven to be a useful tool to predict and track structural arterial changes that reflect arteriosclerosis. The augmentation index (AI) can be used to estimate AS and is derived from the amplitude and timing of the blood pressure (BP) wave reflection in a peripheral artery. ⋯ The association between age and AI was not significant in the SCI population; however, there was a direct association between AI and level of injury. Further, AI was inversely associated with seated systolic blood pressure (SBP) and was increased in individuals who reported orthostatic hypotension (OH) and in those who were physically inactive. In conclusion, individuals with higher cord lesions have more severe cardiovascular autonomic disruption, leading to orthostatic BP dysregulation and physical inactivity, which appear to contribute independently to increased AS in these individuals.
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Journal of neurotrauma · Dec 2017
Systemic Administration of Exosomes Released from Mesenchymal Stromal Cells Attenuates Apoptosis, Inflammation and Promotes Angiogenesis after Contusion Spinal Cord Injury in Rats.
Spinal cord injury (SCI) is one of the most common devastating injuries, which causes permanent disabilities such as paralysis and loss of movement or sensation. The precise pathogenic mechanisms of the disease remain unclear, and, as of yet, there is no effective cure. Mesenchymal stem cells (MSCs) show promise as an effective therapy in the experimental models of SCI. ⋯ Expression levels of proapoptotic protein (Bcl-2-associated X protein) and proinflammatory cytokines (tumor necrosis factor alpha and interleukin [IL]-1β) were significantly decreased after MSCs-exosomes treatment, whereas expression levels of antiapoptotic (B-cell lymphoma 2) and anti-inflammatory (IL-10) proteins were upregulated. Further, administration of MSCs-exosomes significantly promoted angiogenesis. These results show, for the first time, that systemic administration of MSCs-exosomes attenuated cell apoptosis and inflammation, promoted angiogenesis, and promoted functional recovery post-SCI, suggesting that MSCs-exosomes hold promise as a novel therapeutic strategy for treating SCI.
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Journal of neurotrauma · Dec 2017
Risk Factors for Mild Traumatic Brain Injury and Subsequent Post-traumatic Stress Disorder and Mental Health Disorders among US Army Soldiers.
The purpose of this study was to determine the association of mild traumatic brain injury (mTBI) with subsequent post-traumatic stress disorder (PTSD) and mental health disorders (MHD), and the intervening role of acute stress disorder (ASD). This matched case-control study utilized the Total Army Injury and Health Outcomes Database (TAIHOD) to analyze soldiers' (n = 1,261,297) medical encounter data between 2002 and 2011. International Classification of Diseases, Ninth Revision (ICD-9) codes were used to identify: mTBI (following Centers for Disease Control [CDC] surveillance definition for mTBI), MHD (ICD-9 codes for depression and anxiety, excluding PTSD), PTSD (ICD-9 309.81), and ASD (ICD-9 308.3). ⋯ A sub-analysis of the mTBI-only soldiers found that a diagnosis ASD, compared with a diagnosis of no ASD, was associated with greater risk for subsequent PTSD (RR 2.13, 95% CI 1.96-2.32) and MHD (RR 1.90, 95% CI 1.72-2.09) following mTBI. Results indicate that soldiers with previous mTBI have a higher risk for PTSD and MHD, and that ASD may also mediate PTSD and MHD risk subsequent to mTBI. These data may help guide important surveillance and clinical rehabilitation considerations for high-risk populations.