Journal of neurotrauma
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Journal of neurotrauma · Feb 2017
Disruption of locomotion in response to hindlimb muscle stretch at acute and chronic time points after a spinal cord injury in rats.
After spinal cord injury (SCI) muscle contractures develop in the plegic limbs of many patients. Physical therapists commonly use stretching as an approach to avoid contractures and to maintain the extensibility of soft tissues. We found previously that a daily stretching protocol has a negative effect on locomotor recovery in rats with mild thoracic SCI. ⋯ The current study extends our observations of the stretching phenomenon to a more clinically relevant moderately severe SCI animal model. The results are in agreement with our previous findings and further demonstrate that spinal cord locomotor circuitry is especially vulnerable to the negative effects of stretching at chronic time points. While the clinical relevance of this phenomenon remains unknown, we speculate that stretching may contribute to the lack of locomotor recovery in some patients.
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Journal of neurotrauma · Feb 2017
High-Mobility Group Box 1 (HMGB1) is Elevated Systemically in Persons with Acute or Chronic Traumatic Spinal Cord Injury.
Inflammation in traumatic spinal cord injury (SCI) has been proposed to promote damage acutely and oppose functional recovery chronically. However, we do not yet understand the signals that initiate or prolong inflammation in persons with SCI. High-Mobility Group Box 1 (HMGB1) is a potent systemic inflammatory cytokine-or damage-associated molecular pattern molecule (DAMP)-studied in a variety of clinical settings. ⋯ In persons with acute SCI, average HMGB1 levels were significantly elevated within 0-3 days post-injury (6.00 ± 1.8 ng/mL, mean ± standard error of the mean [SEM]) or 4-7 (6.26 ± 1.3 ng/mL, mean ± SEM), compared with controls (1.26 ± 0.24 ng/mL, mean ± SEM; p ≤ 0.001 and p ≤ 0.01, respectively). In persons with chronic SCI who were injured for 15 ± 1.5 years (mean ± SEM), HMGB1 also was significantly elevated, compared with uninjured persons (3.7 ± 0.69 vs. 1.26 ± 0.24 ng/mL, mean ± SEM; p ≤ 0.0001). Together, these data suggest that HMGB1 may be a common, early, and persistent danger signal promoting inflammation in individuals with SCI.
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Journal of neurotrauma · Feb 2017
Left ventricular mechanics in untrained and trained males with tetraplegia.
Reduced left ventricular (LV) function is common in tetraplegia, yet it is unknown whether intrinsic myocardial function is attenuated. This study examined the effect of SCI and exercise-training status on LV mechanics (intrinsic function) and LV systolic/diastolic function by comparing untrained (UT) and trained (TT) individuals with tetraplegia and able-bodied (AB) individuals. Individuals with tetraplegia had a traumatic, chronic, motor-complete cervical spinal cord injury. ⋯ Diastolic mechanics (apical circumferential strain rate) were significantly enhanced in TT (3.03 ± 0.83 s-1) compared to AB (1.85 ± 0.65 s-1; p < 0.05). There was a trend (p = 0.062) for a between-group difference in apical radial diastolic strain rate (UT: -2.51 ± 0.83 s-1; TT: -3.92 ± 1.96 s-1; AB: -1.84 ± 0.46 s-1). In tetraplegia, attenuated LV systolic function is not attributed to intrinsic dysfunction, whereas exercise-training status appears to improve both global LV diastolic function and LV mechanics.
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Journal of neurotrauma · Feb 2017
Comparative StudyTracking Spinal Cord Injury: Differences in cytokine expression of IGF-1, TGF- β1 and sCD95L can be measured in blood samples and corresponds to neurological remission in a 12 week follow-up.
Neuroinflammation presumably has an important impact on the secondary phase of spinal cord injury and is regulated by pro- and anti-inflammatory cytokines. We analyzed serum levels of three different cytokines (insulin-like-growth-factor [IGF]-1, tumor growth factor [TGF]-β1, and soluble CD 95 ligand [sCD95L]), in blood samples of 23 patients admitted with acute traumatic spinal cord injury between November 2010 and July 2013 with a follow-up period of 12 weeks. Quantification was performed using Human Quantikine Immunoassays, classification of neurological impairment was performed using the American Spinal Cord Injury Impairment Scale at time of admission and after 12 weeks. ⋯ In this study, we were able to show differences in cytokine serum levels in patients with different neurological outcome. Measuring the serum level patterns of IGF-1, TGF-β1, and sCD95L might be a useful tool for prognosis in patients with neurological improvement and tracking the pathophysiology in further studies. Further, our observations might link promising therapeutic efforts in numerous animal studies and future studies in human patients.
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Journal of neurotrauma · Feb 2017
Characterising the severity of autonomic cardiovascular dysfunction after spinal cord injury using a novel 24 hour ambulatory blood pressure analysis software.
Cardiovascular disease is one of the leading causes of morbidity and mortality in the spinal cord injury (SCI) population. SCI may disrupt autonomic cardiovascular homeostasis, which can lead to persistent hypotension, irregular diurnal rhythmicity, and the development of autonomic dysreflexia (AD). There is currently no software available to perform automated detection and evaluation of cardiovascular autonomic dysfunction(s) such as those generated from 24 h ambulatory blood pressure monitoring (ABPM) recordings in the clinical setting. ⋯ Cervical SCI presented with more frequent (p = 0.0043) and severe AD (p = 0.0343) than did high thoracic SCI. Cervical SCI exhibited higher systolic and diastolic blood pressure during the night and lower heart rate during the day than high thoracic SCI. In conclusion, our ABPM AD Detection Software was equally as effective in detecting the frequency and severity of AD and hypotensive events as manual detection, suggesting that this software can be used in the clinical setting to expedite ABPM analyses.