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OBJECT: The April 27, 2011, tornados that affected the southeastern US resulted in 248 deaths in the state of Alabama. The University of Alabama at Birmingham (UAB) Medical Center, the largest Level I trauma center in the state, triaged and treated a large number of individuals who suffered traumatic injuries during these events, including those requiring neurosurgical assessment and treatment. METHODS: A retrospective review of all adult patients triaged at UAB Medical Center during the April 27, 2011, tornados was conducted. Those patients who were diagnosed with and treated for neurosurgical injuries were included in this cohort. RESULTS: The Division of Neurosurgery at UAB Medical Center received 37 consultations in the 36 hours following the tornado disaster. An additional patient presented 6 days later, having suffered a lumbar spine fracture that ultimately required operative intervention. Twenty-seven patients (73%) suffered injuries as a direct result of the tornados. Twenty-three (85%) of these 27 patients experienced spine and spinal cord injuries. Four patients (15%) suffered intracranial injuries and 2 patients (7%) suffered combined intracranial and spinal injuries. The spinal fractures that were evaluated and treated were predominantly thoracic (43.5%) and lumbar (43.5%). The neurosurgery service performed 14 spinal fusions, 1 ventriculostomy, 2 halo placements, 1 diagnostic angiogram, 1 endovascular embolectomy, and 1 wound debridement and lavage. Twenty-two patients (81.5%) were neurologically intact at discharge and all but 4 had 1 year of follow-up. Three patients had persistent deficits from spinal cord injuries and there was 1 death in a patient with multisystem injuries in whom no procedures were performed. Two patients experienced postoperative complications in the form of 1 wound infection and 1 stroke. CONCLUSIONS: The April 27, 2011, tornados in Alabama produced significant neurosurgical injuries that primarily involved the spine. There were a disproportionate number of patients with thoracolumbar fractures, a finding possibly due to the county medical examiner's postmortem findings that demonstrated a high prevalence of fatal cervical spine and traumatic brain injuries. The UAB experience can be used to aid other institutions in preparing for the appropriate allotment of resources in the event of a similar natural disaster.

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In order to compensate for the inherent high threshold of detectability of MR contrast agents, there has been an active interest in the development of paramagnetic nanoparticles incorporating high payloads of Gd(3+) with high molecular relaxivities. Toward this end, the protein cage of Cowpea chlorotic mottle virus (CCMV), having 180 metal binding sites, is being explored. In vivo CCMV binds Ca(2+) at specific metal binding sites; however, Gd(3+) can also bind at these sites. Using fluorescence resonance energy transfer we have characterized the binding affinity of Gd(3+) to the metal binding sites by competition experiments with Tb(3+). The measured dissociation constant (K(d)) for Gd(3+) bound to the virus is 31 microM. The T(1) and T(2) relaxivities of solvent water protons in the presence of Gd(3+)-bound CCMV were 202 and 376 mM(-1) s(-1), respectively, at 61 MHz Larmor frequency. The unusually high relaxivity values of the Gd(3+)-CCMV are largely a result of the nanoparticle virus size and the large number of Gd(3+) ions bound to the virus. These preliminary results should encourage further investigations into the use of viral protein cages as a new platform for MR contrast agents.

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Stem cell transplantation is being explored as a new paradigm for the treatment of demyelinating diseases. Magnetically labeled multipotential neural precursor cells were transplanted into the ventricles of rats with acute experimental allergic encephalomyelitis (EAE) and high-resolution (microscopic) MR images were obtained ex vivo. Migration patterns of live cells into periventricular white matter structures could be easily visualized, with a good correlation of the corresponding histopathology. The present results confirm that MR cell tracking can be used to guide the development of successful transplantation protocols.

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PURPOSE: To label mammalian and stem cells by combining commercially available transfection agents (TAs) with superparamagnetic iron oxide (SPIO) magnetic resonance (MR) imaging contrast agents. MATERIALS AND METHODS: Three TAs were incubated with ferumoxides and MION-46L in cell culture medium at various concentrations. Human mesenchymal stem cells, mouse lymphocytes, rat oligodendrocyte progenitor CG-4 cells, and human cervical carcinoma cells were incubated 2-48 hours with 25 microg of iron per milliliter of combined TAs and SPIO. Cellular labeling was evaluated with T2 relaxometry, MR imaging of labeled cell suspensions, and Prussian blue staining for iron assessment. Proliferation and viability of mesenchymal stem cells and human cervical carcinoma cells labeled with a combination of TAs and ferumoxides were evaluated. RESULTS: When ferumoxides-TA or MION-46L-TA was used, intracytoplasmic particles stained with Prussian blue stain were detected for all cell lines with a labeling efficiency of nearly 100%. Limited or no uptake was observed for cells incubated with ferumoxides or MION-46L alone. For TA-SPIO-labeled cells, MR images and relaxometry findings showed a 50%-90% decrease in signal intensity and a more than 40-fold increase in T2s. Cell viability varied from 103.7% +/- 9 to 123.0% +/- 9 compared with control cell viability at 9 days, and cell proliferation was not affected by endosomal incorporation of SPIO nanoparticles. Iron concentrations varied with ferumoxides-TA combinations and cells with a maximum of 30.1 pg +/- 3.7 of iron per cell for labeled mesenchymal stem cells. CONCLUSION: Magnetic labeling of mammalian cells with use of ferumoxides and TAs is possible and may enable cellular MR imaging and tracking in experimental and clinical settings.

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R2* mapping has recently been used to detect iron overload in patients with movement disorders. We demonstrate here that this technique can also be used to detect reduced brain iron, as in the case of a missense mutation in the iron-transporting protein divalent metal transporter 1. Surprisingly, we found that the same brain regions are affected (ie, the globus pallidus, substantia nigra, and cerebellar dentate nucleus); this suggests a much more extensive role for these structures in regulating overall brain iron homeostasis. Therefore, for the clinical monitoring of movement disorders for which normal brain iron homeostasis (either overload or reduction) may be implicated, R2* mapping appears to be well-suited.

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