Ex vivo adenoviral vector-mediated neurotrophin gene transfer to olfactory ensheathing glia: Effects on rubrospinal tract regeneration, lesion size, and functional recovery after implantation in the injured rat spinal cord

The present study uniquely combines olfactory ensheathing glia (OEG) implantation with ex vivo adenoviral (AdV) vector-based neurotrophin gene therapy in an attempt to enhance regeneration after cervical spinal cord injury. Primary OEG were transduced with AdV vectors encoding rat brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), or bacterial marker protein -galactosidase (LacZ) and subsequently implanted into adult Fischer rats directly after unilateral transection of the dorsolateral funiculus. Implanted animals received a total of 2 x 105 OEG that were subjected to transduction with neurotrophin-encoding AdV vector, AdV-LacZ, or no vector, respectively. At 4 months after injury, lesion volumes were smaller in all OEG implanted rats and significantly reduced in size after implantation of neurotrophin-encoding AdV vector-transduced OEG. All OEG grafts were filled with neurofilament-positive axons, and AdV vector-mediated expression of BDNF by implanted cells significantly enhanced regenerative sprouting of the rubrospinal tract. Behavioral analysis revealed that OEG-implanted rats displayed better locomotion during horizontal rope walking than unimplanted lesioned controls. Recovery of hind limb function was also improved after implantation of OEG that were transduced with a BDNF- or NT-3-encoding AdV vector. Hind limb performance during horizontal rope locomotion did directly correlate with lesion size, suggesting that neuroprotective effects of OEG implants contributed to the level of functional recovery. Thus, our results demonstrate that genetic engineering of OEG not only resulted in a cell that was more effective in promoting axonal outgrowth but could also lead to enhanced recovery after injury, possibly by sparing of spinal tissue

Eenvoudige adoptie. De behoeften en belangen van pleegkinderen en oorspronkelijke ouders

Education and Child Studie

Feasibility study of real-time three-/four-dimensional ultrasound for epidural catheter insertion

Background Real-time two-dimensional (2D) ultrasound can be used to facilitate neuraxial anaesthesia. Four-dimensional (4D) ultrasound allows the use of multiple imaging planes and three-dimensional reconstruction of ultrasound data. We assessed how 4D ultrasound could be used to perform epidural catheter insertion in a cadaver model. We then also compared 4D ultrasound and a previously described 2D technique in real-time epidural catheterization. Methods Epidural catheter insertion was attempted on four embalmed cadavers using a variety of 4D techniques. A feasible, 4D ultrasound-guided in-plane needle insertion technique was then compared qualitatively with the 2D technique in a further six cadavers. Results A feasible technique of real-time 4D ultrasound-guided epidural insertion used two perpendicular imaging planes to improve the orientation of the operator. It resulted in changes in the needle direction in half of the approaches. Using 4D ultrasound, the Tuohy needle could only be seen reliably in the primary imaging plane. In-plane needle visibility using 4D imaging was inferior to 2D imaging. Successful epidural catheterization was also aided by an acoustic window being present, which allowed visualization of the vertebral body. Conclusions The study demonstrates that 4D ultrasound can be used for real-time epidural catheter insertion and has both advantages and limitations compared with the 2D technique. Four-dimensional ultrasound has the potential to improve operator orientation on the vertebral column. However, this comes at the price of decreased resolution, frame rate, and needle visibility. Prospective evaluation of the importance of an acoustic window in neuraxial anaesthesia is required