Journal of neurotrauma
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In peripheral nerve injury, end-to-side neurorrhaphy has been reported as an alternative in cases that the proximal nerve stump is not accessible. Several hypotheses have been proposed to explain peripheral nerve regeneration after end-to-side neurorrhaphy. Recent evidence suggests that nerve regeneration occurs by collateral sprouting. ⋯ The goal of this technique is to provide satisfactory functional recovery for the recipient nerve, without any deterioration of the donor nerve function. End-to-side technique has been investigated in detail in both experimental and clinical studies. Only a limited number of reported cases in clinical practice, until today, can reveal that end-to-side technique may become a viable means of repairing peripheral nerves in certain clinical situations.
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Journal of neurotrauma · May 2007
Transplantation of adult rat spinal cord stem/progenitor cells for spinal cord injury.
Stem/progenitor cells derived from the ependymal region of the spinal cord have the ability to self-renew and are multipotential for neurons and glia. These cells may have the ability to regenerate the injured mammalian spinal cord as they do in some lower vertebrates. However, the optimal conditions for transplantation and the fate of transplanted cells are not fully known. ⋯ A significant increase in cell survival was also seen in rats receiving subacute transplants at 9 days after injury. Transplanted cells differentiated primarily into astrocytes (31.2%) and oligodendrocytes (50.3%), and a small number of neurons (1%). No improvement was seen in the Basso, Beattie and Bresnahan (BBB) locomotor rating scale after acute transplantation as compared with injury only, although surviving transplanted cells were identified that had migrated across the injury site from the rostral and caudal injection sites.
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Journal of neurotrauma · May 2007
Quantitative characterization of regenerating axons after end-to-side and end-to-end coaptation in a rat brachial plexus model: a retrograde tracer study.
The efficacy of end-to-side repair as a method of nerve reconstruction has been questioned, and most studies that characterize the mode of re-innervation are marred by inappropriate experimental design and lack quantitative analysis. This makes characterization of re-innervating neurons confusing and consequently controversy remains as to the extent and source of reinnervating axons. In an experimental brachial plexus rat model, we transected the musculocutaneous nerve, labeled its neuron pool with Fast-Blue and joined the distal stump to the side of the intact ulnar nerve, or to the proximal stump of the divided ulnar nerve, to characterize neurons that reinnervate the recipient nerve. ⋯ In the end-to-side group, 16.4% of the motor and 7% of the sensory donor ulnar nerve neurons re-innervated the musculocutaneous nerve exclusively, and a further 10% motor and 11.6% sensory innervated the musculocutaneous nerve by collateral sprouting of their axons. This compared to re-innervation by 62.6% of motor and 70.4% of ulnar nerve sensory neurons in the positive control that underwent end-to-end repair. Our results confirm the concept of collateral sprouting and support the use of end-to-side repair.
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Journal of neurotrauma · May 2007
Apolipoprotein E4 allele presence and functional outcome after severe traumatic brain injury.
Presence of the apolipoprotein E (APOE) 4 allele has been associated with increased incidence and faster progression of neurodegenerative diseases, poorer recovery from neurologic insult, and decreased cognitive function in the well-elderly. The specific association between APOE genotype and recovery from severe traumatic brain injury (TBI) is conflicting with many groups finding the APOE 4 allele to be associated with poorer outcome while others have found no association. The purpose of this study was to investigate the association between APOE 4 allele presence and recovery during the two years after injury from severe TBI in light of other potential covariates, such as age, race, gender, hypotension or hypoxia before hospital admission and severity of injury. ⋯ We did not however find significant differences in GOS at individual time points when controlling for other covariates. Our findings suggest that APOE 4 allele presence influences recovery rate from severe TBI independent of other covariates. The findings of this study are unique in that they address not only the relationship between APOE 4 allele presence and outcome from severe TBI, but also describe differences in trajectory of recovery by APOE 4 allele presence.
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Journal of neurotrauma · May 2007
Diffuse axonal injury in severe traumatic brain injury visualized using high-resolution diffusion tensor imaging.
Traumatic brain injury (TBI) is the most common cause of death and disability in young people. The functional outcome in patients with TBI cannot be explained by focal pathology alone, and diffuse axonal injury (DAI) is considered a major contributor to the neurocognitive deficits experienced by this group. The aim of the present study was to investigate whether diffusion tensor imaging (DTI) offers additional information as to the extent of damage not visualized with standard magnetic resonance imaging (MRI) in patients with severe TBI. ⋯ The findings of this study support the hypothesis that severe TBI is accompanied by DAI. The DTI changes were more prominent on the right side that contained the focal pathology in most of the patients and accurately reflected differences in both hemispheres. In conclusion, DTI holds great promise as a diagnostic tool to identify and quantify the degree of white matter injury in TBI patients.