Schwann Cell Precursor Transplant in a Rat Spinal Cord Injury Model.

BACKGROUND: Differentiation of mesenchymal stem cells into Schwann cell precursors could reverse established lesions and sequelae of medullary transection. OBJECTIVE: The objective of this study was to study the clinical response of mesenchymal stem cell transplantation with Schwann precursor cell transplantation in a rat spinal cord injury model, using motor function and histopathologic studies. MATERIALS AND METHODS: A total of 28 Sprague-Dawley rats were randomly divided among four groups (n = 7 in each): sham group, control group, mesenchymal stem cell transplant group, and Schwann cell precursor transplant group. The surgical procedure was a laminectomy with transection of the spinal cord at the T11 level in the transplant groups and the injury control group. After 1 week, the transplant groups received stem cells directly in the injury site. Hind limb motor function was assessed using the locomotive scale of Basso, Beattie, and Bresnahan. 1 month after transplantation, all specimens were sacrificed to make a histopathologic description of sections taken from the site of injury and where stem cells were transplanted. Mean scores of mobility were compared using analysis of variance (ANOVA) of one factor with 95% reliability between groups and ANOVA of repetitive measures to evaluate evolution in the same group. RESULTS: We observed that the control group had statistically greater mobility than the other groups (p < 0.0001) and that the group with spinal injury without treatment had the lowest mean mobility. The mobility score values from the Schwann cell precursor group were statistically higher than the group treated with mesenchymal stem cells (p < 0.0001). CONCLUSION: Schwann precursor cells had a greater effect on locomotive function than mesenchymal stem cells.

Cell-assisted lipotransfer for the treatment of parry-romberg syndrome.

Progressive facial hemiatrophy, also known as Parry-Romberg syndrome, is a progressive and self-limited deformation of the subcutaneous tissue volume on one side of the face that creates craniofacial asymmetry. We present the case of a patient with a five-year history of progressive right facial hemiatrophy, who underwent facial volumetric restoration using cell-assisted lipotransfer (CAL), which consists of an autologous fat graft enriched with adipose-derived stem cells (ASCs) extracted from the same patient. ASCs have the capacity to differentiate into adipocytes. They also promote angiogenesis, release angiogenic growth factors, and some can survive as stem cells. The use of autologous fat as a filler in soft tissue atrophy has been satisfactory in patients with mild and moderate Parry-Romberg syndrome. Currently, CAL has showed promising results in the long term by decreasing the rate of fat reabsorption. The permanence and stability of the graft in all the injected areas has showed that autologous fat grafts enriched with stem cells could be a promising technique for the correction of defects caused by this syndrome.

Modification of the technique for subclavian-vein catheterization.

INTRODUCTION: In invasive monitoring, subclavian-vein puncture is a routine procedure indicated for central vein cathe-terization. It is indicated in patients according to hospital stay, including the administration of drugs and the treatment of chronic and cardiac disease. The techniques described to date include infraclavicular percutaneous puncture; others place catheters using angiographic methods, and the use of magnetic resonance imaging and ultrasound has also been reported. Studies have been done in cadavers to get a better understanding of the procedure since the relationship between vascular elements and surrounding tissues are obtained. The usual technique is with the patient in Trendelenburg position, with the arm in adduction, the placement of an interscapular roll, and the head turned away from the puncture site. OBJECTIVE: The aim of this study was to demonstrate less frequent technical failures and complications using a modification of the usual technique. We propose catheterization of the right subclavian vein with the patient in decubitus, without an interescapular roll, with the arm in abduction and using the distal third of the clavicle and the suprasternal notch as anatomical references. RESULTS: Two technical puncture failures and three complications occurred in a total of 42 patients with a statistically significant difference (p = 0.0410) in frequency (11.9%) from that reported with the traditional technique (21.8%). CONCLUSIONS: Greater efficacy with the technique modified by the authors was confirmed. Anatomical cadaver dissections showed a greater space between the right subclavian vein and the clavicle.