Journal of neurotrauma
-
Journal of neurotrauma · Feb 2013
Inhibition of Nogo-66 receptor 1 enhances recovery of cognitive function after traumatic brain injury in mice.
Central nervous system (CNS) axons recover poorly following injury because of the expression of myelin-derived inhibitors of axonal outgrowth such as Nogo, myelin-associated glycoprotein (MAG), and oligodendrocyte-myelin glycoprotein (OMgp), all of which bind to the Nogo-66 receptor 1 (NgR1). Herein we examine the role of NgR1 in the recovery of motor and cognitive function after traumatic brain injury (TBI) using a controlled cortical impact (CCI) model in NgR1 knockout (KO) and wild-type (WT) mice. Four weeks post-injury, scores on the Novel Object Recognition test were significantly increased in NgR1 KO mice compared with WT mice (p<0.05), but motor behavior test scores did not differ significantly between the two groups. ⋯ The number of bromodeoxyuridine (BrdU)+ cells did not differ between the two groups at 4 weeks post-trauma, but KO mice had higher numbers of cells that co-stained with NeuN, a marker of mature neurons. Increased transcription of growth-associated protein (GAP)-43 in both the injured and contralateral sides of the hippocampus (both p<0.05) was detected in NgR1 KO mice relative to WT. These data suggest that NgR1 negatively influences plasticity and cognitive recovery after TBI.
-
Journal of neurotrauma · Feb 2013
Trauma-induced coagulopathy: standard coagulation tests, biomarkers of coagulopathy, and endothelial damage in patients with traumatic brain injury.
It remains to be debated whether traumatic brain injury (TBI) induces a different coagulopathy than does non-TBI. This study investigated traditional coagulation tests, biomarkers of coagulopathy, and endothelial damage in trauma patients with and without TBI. Blood from 80 adult trauma patients was sampled (median of 68 min [IQR 48-88] post-injury) upon admission to our trauma center. ⋯ No significant biomarker differences were found between isoTBI and non-TBI patients. Injury severity scale (ISS) rather than the presence or absence of head/neck injuries determined the hemostatic and biomarker response to the injury. The coagulopathy identified thus reflected the severity of injury rather than its localization.
-
Journal of neurotrauma · Feb 2013
Pituitary function and functional outcome in adults after severe traumatic brain injury: the long-term perspective.
Post-traumatic hypopituitarism (PTHP) has been linked to disability and decreased quality of life. However, no studies have addressed the long-term consequences of PTHP in adults with severe traumatic brain injury (TBI) only. In this study, we evaluated the relationship between pituitary function, quality of life, and functioning in 51 patients (16-65 years of age) with severe TBI who were admitted to Sahlgrenska University Hospital, Gothenburg from 1999 to 2002. ⋯ Otherwise no significant correlation was found among PTHP, functioning, or patient-reported quality of life. This study-which is unique in the homogeneity of the patients, the long follow-up time, and the use of injury severity as an outcome predictor-did not confirm results from previous studies linking PTHP to a worse outcome. Therefore, screening for PTHP might be restricted to specific subgroups such as overweight patients, indicating growth hormone deficiency.
-
Journal of neurotrauma · Feb 2013
Risk factors for postconcussion symptom reporting after traumatic brain injury in U.S. military service members.
The purpose of this study was to identify factors that are predictive of, or associated with, postconcussion symptom reporting after traumatic brain injury (TBI) in the U. S. military. Participants were 125 U. ⋯ PCD rarely occurred in the absence of depression, traumatic stress, possible symptom exaggeration, or poor effort (n=7, 5.6%). Many factors unrelated to brain injury were influential in self-reported postconcussion symptoms in this sample. Clinicians cannot assume uncritically that endorsement of items on a postconcussion symptom checklist is indicative of residual effects from a brain injury.
-
Journal of neurotrauma · Feb 2013
The effect of environmental enrichment on substantia nigra gene expression after traumatic brain injury in rats.
Experimental investigations into the effects of traumatic brain injury (TBI) have demonstrated significant alterations in dopaminergic systems. Dopaminergic fibers originating within the substantia nigra and ventral tegmental area (VTA) are important for reward learning, addiction, movement, and behavior. However, little is known about the effect of TBI on substantia nigra and VTA function. ⋯ Chronic alterations in genes post-injury within the substantia nigra and VTA included genes important for cellular membrane homeostasis and transcription. EE-induced gene alterations after TBI included genes important for signal transduction, in particular calcium signaling pathways, membrane homeostasis, and metabolism. Elucidation of these alterations in gene expression within the substantia nigra and VTA provides new insights into chronic changes in dopamine signaling post-TBI, and the potential role of EE in TBI rehabilitation.