Journal of neurotrauma
-
Journal of neurotrauma · Jan 2015
GENETIC ACTIVATION OF mTORC1 SIGNALING WORSENS NEUROCOGNITIVE OUTCOME AFTER TRAUMATIC BRAIN INJURY.
Although the mechanisms that contribute to the development of traumatic brain injury (TBI)-related deficits are not fully understood, it has been proposed that altered energy utilization may be a contributing factor. The tuberous sclerosis complex, a heterodimer composed of hamartin/Tsc-1 and tuberin/Tsc-2, is a critical regulatory node that integrates nutritional and growth signals to govern energy using processes by regulating the activity of mechanistic Target of Rapamycin complex 1 (mTORC1). mTORC1 activation results in enhanced protein synthesis, an energy consuming process. ⋯ This enhanced level of increased mTORC1 activity was associated with worsened cognitive function as assessed using the Morris water maze and context discrimination tasks. These results suggest that there is a threshold of increased mTORC1 activity after a TBI that is detrimental to neurobehavioral performance, and interventions to inhibit excessive mTORC1 activation may be beneficial to neurocognitive outcome.
-
Journal of neurotrauma · Jan 2015
Quantitative lobar cerebral blood flow for outcome prediction after traumatic brain injury.
The aim of this study was to examine cortical cerebral blood flow (CBF) in patients with traumatic brain injury (TBI) and determine whether lobar cortical CBF is a better predictor of long-term neurological outcome assessed by the Glasgow Outcome Scale (GOS) than global cortical CBF. Ninety-eight patients with TBI had a stable xenon computed tomography scan (Xe/CT-CBF study) performed at various time points after their initial injury. Spearman's correlation coefficients and Kruskall-Wallis' test were used to examine the relationship between patient age, emergency room Glasgow Coma Scale (GCS), Injury Severity Score, prehospital hypotension, prehospital hypoxia, mechanism of injury, type of injury, side of injury, global average CBF, lobar CBF, number of lobes with CBF below normal, and GOS (discharge, 3 and 6 months). ⋯ PCA found one principle component among these three CBF variables; therefore, average global CBF and number of lobes with CBF below normal were each chosen as independent variables for multiple ordinal regression, which found age, GCS, and prehospital hypotension, global average CBF, and number of lobes below normal CBF significantly associated with GOS. This study found global average CBF and lobar CBF significantly correlated with GOS at follow-up. There was, however, no individual cerebral lobe that was more predictive than any other, which puts into question the value of calculating lobar CBF versus global CBF in predicting GOS.
-
Risk factors for head injury are also risk factors for becoming homeless but there is little research on this vulnerable group, who can be neglected by health services that specialize in acquired brain injury. This study investigates the prevalence of admissions to hospital with a head injury in the homeless and associations with later mortality. It compares homeless people with and without a record of hospitalized head injury (HHI) and the Glasgow population. ⋯ The standardized mortality ratio for HHI (4.51) was more than twice that for NHHI (2.08). The standardized mortality ratio for HHI aged 15-34 (17.54) was particularly high. These findings suggest that HHI is common in the homeless relative to the general population and is a risk factor for late mortality in the homeless population.
-
Journal of neurotrauma · Jan 2015
GCS motor score and pupillary reaction to predict six month mortality in patients with TBI: comparison of field and admission assessment.
The Glasgow Coma Scale (GCS) and pupillary reactivity are well-known prognostic factors in traumatic brain injury (TBI). The aim of this study was to compare the GCS motor score and pupillary reactivity assessed in the field and at hospital admission and assess their prognostic value for 6-month mortality in patients with moderate or severe TBI. We studied 445 patients with moderate or severe TBI from Austria enrolled to hospital in 2009-2012. ⋯ This combination also showed best performance in the adjusted analyses (AUC=0.876; R(2)=0.508), but the performance of both predictors assessed at admission was not much worse (AUC=0.857; R(2)=0.460). Field GCS motor score and pupillary reactivity at hospital admission, compared to other combinations of these parameters, possess the best prognostic value to predict 6-month mortality in patients with moderate-to-severe TBI. Given that differences in prognostic performance are only small, both the field and admission values of GCS motor score and pupillary reaction may be reasonable to use in multi-variable prediction models to predict 6-month outcome.
-
Journal of neurotrauma · Jan 2015
Methylene Blue Attenuates Traumatic Brain Injury-associated Neuroinflammation and Acute Depressive-like Behavior in Mice.
Traumatic brain injury (TBI) is associated with cerebral edema, blood brain barrier breakdown, and neuroinflammation that contribute to the degree of injury severity and functional recovery. Unfortunately, there are no effective proactive treatments for limiting immediate or long-term consequences of TBI. Therefore, the objective of this study was to determine the efficacy of methylene blue (MB), an antioxidant agent, in reducing inflammation and behavioral complications associated with a diffuse brain injury. ⋯ Nonetheless, MB attenuated the development of acute depressive-like behavior at 7 d post injury. Taken together, immediate intervention with MB was effective in reducing neuroinflammation and improving behavioral recovery after diffuse brain injury. Thus, MB intervention may reduce life-threatening complications of TBI, including edema and neuroinflammation, and protect against the development of neuropsychiatric complications.