Journal of neurotrauma
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Journal of neurotrauma · Sep 2011
Structured assessment of hypopituitarism after traumatic brain injury and aneurysmal subarachnoid hemorrhage in 1242 patients: the German interdisciplinary database.
Clinical studies have demonstrated that traumatic brain injury (TBI) and aneurysmal subarachnoid hemorrhage (SAH) are frequent causes of long-term disturbances of hypothalamo-pituitary function. This study aimed to assess the prevalence and associated factors of post-traumatic hypopituitarism in a large national registry of patients with TBI and SAH. Data were collected from 14 centers in Germany and Austria treating patients for TBI or SAH and performing endocrine assessments. ⋯ TBI patients with abnormal stimulation tests had suffered from more severe TBI than patients with normal stimulation tests. In conclusion, our data confirm that hypopituitarism is a common complication of TBI and SAH. It is possible that patients with a higher likelihood of hypopituitarism were selected for endocrine stimulation tests.
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Journal of neurotrauma · Sep 2011
Mild stretch-induced injury increases susceptibility to interleukin-1β-induced release of matrix metalloproteinase-9 from astrocytes.
Traumatic brain injury (TBI) results in the activation of glia and the release of proinflammatory cytokines, including interleukin (IL)-1β. The response of astrocytes to mild TBI has not been well studied. We used an in vitro model of cell stretch to investigate the effects of mild mechanical insult on astrocyte injury (lactate dehydrogenase and propidium iodide), and on mediators of inflammation including IL-1β, the chemokine CX3CL1, and nitrite. ⋯ In contrast, the combination of mild stretch followed by IL-1β resulted in greater activation of the ERK pathway compared to either stimulus alone, and also resulted in an increase in the production of MMP-9 by astrocytes. Inhibition of the ERK pathway suppressed the increase in MMP-9 induced by the combination of stretch and IL-1β treatment. These results suggest that a primary mild mechanical injury renders astrocytes more susceptible to a secondary exposure to a proinflammatory cytokine such as IL-1β via the activation of the ERK pathway, and suggest a mechanism by which a mild head injury may confer increased susceptibility to neurologic injury caused by a subsequent insult.
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Journal of neurotrauma · Sep 2011
Correlation of MR diffusion tensor imaging parameters with ASIA motor scores in hemorrhagic and nonhemorrhagic acute spinal cord injury.
This study investigated correlations between American Spinal Injury Association (ASIA) clinical injury motor scores in patients with traumatic cervical cord injury and magnetic resonance (MR) diffusion tensor imaging (DTI) parameters. Conventional imaging and DTI were performed to evaluate 25 patients (age, 39.7±13.9 years; 4 women, 21 men) with blunt spinal cord injury and 11 volunteers (age, 31.5±10.7 years; 3 women, 8 men). Cord contusions were hemorrhagic (HC) in 13 and non-hemorrhagic (NHC) in 12 patients. ⋯ Within the NHC group, strong correlations were observed between ASIA motor scores and average MD, FA, λ(⊥), and λ(‖) at the injury site. However, no correlation was observed within the HC group between any of the DTI parameters and ASIA motor scores. DTI parameters reflect the severity of spinal cord injury and correlate well with ASIA motor scores in patients with NHC.
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Journal of neurotrauma · Sep 2011
Acetylcholinesterase inhibition and locomotor function after motor-sensory cortex impact injury.
Traumatic brain injury (TBI) induces transient or persistent dysfunction of gait and balance. Enhancement of cholinergic transmission has been reported to accelerate recovery of cognitive function after TBI, but the effects of this intervention on locomotor activity remain largely unexplored. The hypothesis that enhancement of cholinergic function by inhibition of acetylcholinesterase (AChE) improves locomotion following TBI was tested in Sprague-Dawley male rats after a unilateral controlled cortical impact (CCI) injury of the motor-sensory cortex. ⋯ PHY improved performance in the accelerating Rotarod at 1.6 and 3.2 μmol/kg/day (AChE activity 95 and 78% of control, respectively), however, higher doses induced progressive deterioration. No effect or worsening of outcomes was observed at all PHY doses for home cage activity, rearing, and horizontal ladder walking. Potential benefits of cholinesterase inhibition on locomotor function have to be weighed against the evidence of the narrow range of useful doses.
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Journal of neurotrauma · Sep 2011
Kinematic study of locomotor recovery after spinal cord clip compression injury in rats.
After spinal cord injury (SCI), precise assessment of motor recovery is essential to evaluate the outcome of new therapeutic approaches. Very little is known on the recovery of kinematic parameters after clinically-relevant severe compressive/contusive incomplete spinal cord lesions in experimental animal models. In the present study we evaluated the time-course of kinematic parameters during a 6-week period in rats walking on a treadmill after a severe thoracic clip compression SCI. ⋯ We also showed that treadmill training increased the swing duration variability during locomotion suggesting an activity-dependent compensatory mechanism of the motor control system. However, no effect of training was observed on the main locomotor parameters probably due to a ceiling effect of self-training in the cage. These findings constitute a kinematic baseline of locomotor recovery after clinically relevant SCI in rats and should be taken into account when evaluating various therapeutic strategies aimed at improving locomotor function.