DNA polymorphisms as tools for spinal cord injury research.

STUDY DESIGN: Data mining of single nucleotide polymorphisms (SNPs) in gene pathways related to spinal cord injury (SCI). OBJECTIVES: To identify gene polymorphisms putatively implicated with neuronal damage evolution pathways, potentially useful to SCI study. SETTING: Departments of Psychiatry and Orthopedics, Faculdade de Medicina, Universidade de São Paulo, Brazil. METHODS: Genes involved with processes related to SCI, such as apoptosis, inflammatory response, axonogenesis, peripheral nervous system development and axon ensheathment, were determined by evaluating the 'Biological Process' annotation of Gene Ontology (GO). Each gene of these pathways was mapped using MapViewer, and gene coordinates were used to identify their polymorphisms in the SNP database. As a proof of concept, the frequency of subset of SNPs, located in four genes (ALOX12, APOE, BDNF and NINJ1) was evaluated in the DNA of a group of 28 SCI patients and 38 individuals with no SC lesions. RESULTS: We could identify a total of 95,276 SNPs in a set of 588 genes associated with the selected GO terms, including 3912 nucleotide alterations located in coding regions of genes. The five non-synonymous SNPs genotyped in our small group of patients, showed a significant frequency, reinforcing their potential use for the investigation of SCI evolution. CONCLUSION: Despite the importance of SNPs in many aspects of gene expression and protein activity, these gene alterations have not been explored in SCI research. Here we describe a set of potentially useful SNPs, some of which could underlie the genetic mechanisms involved in the post trauma spinal cord damage.

Effect of the trauma mechanism on the bladder-sphincteric behavior after spinal cord injury.

STUDY DESIGN: Retrospective study. OBJECTIVE: To determine if spinal cord injuries due to gunshot wounds (GW) are associated with different bladder and sphincteric behavior compared to other trauma mechanisms. SETTING: Spinal injury center, Brazilian university hospital. METHODS: We retrospectively evaluated the records and urodynamic studies of 71 patients with spinal cord injury (SCI) referred to the Brazilian National Spinal Cord Injury Center over the year 2000, and compared the bladder-sphincteric pattern of patients with injuries caused by GW with those caused by other trauma mechanisms. RESULTS: The causes of SCI were (1) gunshot wounds (31 patients: 43.7%); (2) motor vehicle accidents (16 patients: 22.5%); (3) falls (16 patients: 22.5%) and (4) diving (three patients: 4.2%). In five patients (7.1%) the causes were unusual trauma mechanisms like stab wound (one patient) and direct trauma in vigorous sports (two patients) or fights (two patients). The levels of the injuries were cervical in 22 patients (31.0%), thoracic in 39 (54.9%) and lumbar in 10 (14.1%). Detrusor hyperreflexia with detrusor-sphincter dyssynergia was present in 65% of the patients overall and in 76% of the thoracic gunshot wounded. Areflexia occurred in 20% of the patients and in 16% of thoracic injured patients with gunshots. Detrusor hyperreflexia with detrusor-sphincter dyssynergia was the pattern encountered in 50% of the individuals suffering from SCI because of other mechanisms and areflexia was present in 35.8%. There was no statistical difference between GW patients and other mechanisms according to bladder and sphincter functions. CONCLUSIONS: There was a substantial overlap of bladder and sphincteric behaviors between patients with different levels of spinal injuries, but the trauma mechanism was not important to determine the bladder and sphincteric functions.