Zogopoulos Panagiotis is a resident of Neurosurgery at the General Hospital of Nikaia-Piraeus “Agios Panteleimon”, Athens, Greece. He has received a 6-month advanced clinical training (clinical fellow) at the Neurosurgery Department of Osaka University Hospital in Japan, where an ongoing clinical trial about spinal cord transplantation with olfactory mucosa autograft is being conducted. Several of his papers have been published in reputed peer-review journals and he has presented various researches in international conferences.
Transplantation of embryonic neural tissues was introduced as a technique of damaged neuronal circuitries repair since the late 1970s, however due to ethic issues, research has recently been focused on stem cells transplantation, such as olfactory mucosa neurons. Patients with complete paraplegia (ASIA grade A or B) due to spinal cord injury more than 6 months previously and with less than 3cm vertical extent of cord injury on MRI, have been included in a relevant clinical trial at the Neurosurgery Department of Osaka University Hospital. The patient\'s olfactory mucosa graft is taken endoscopically and then processed into small pieces. Afterwards, spinal cord\'s posterior medial sulcus is opened, the scar is removed and the autograft is transplanted into the cavity. Patients have demonstrated electromyographic signals in response to voluntary effort as early as 3 months after the transplantation, while emergence of motor evoked potential has also been observed, indicating the recovery of electrophysiological conductivity of the corticospinal tract. Moreover, some patients have shown improvement in motor function below the level of injury. The neural condition of the severed caudal spinal cord seems to influence the potential for motor function recovery, while the time interval between injury and transplantation does not seem to be an important factor since improvement from ASIA grade A to grade D has been achieved in one patient even when the transplantation was performed ten years after the injury. Involuntary muscle spasm before transplantantion seems to be a predictor of success of regenerative treatment in chronic spinal cord injury patients.
Mahboubeh Nabavinia is a Ph.D. student from Iran. She is working on her Ph.D. thesis in Tissue Engineering and Stem Cell Research Lab. The objective of her Ph.D. dissertation is study on generation of modular bone tissue in fluidized bed bioreactor using core-shell microcapsule technique. She used electrostatic technique for entrapping MG63 cells or ADMSCs in core- shell microcapsule. She published some papers in these fields such as modeling bioreactor for tissue engineering application in 9th Royan international congress on stem cell biology and technology.
Three dimensional matrices that encapsulate stem cells are promising for cell growth and tissue formation in tissue engineering and regenerative medicine. The aim of this study was utilizing a simple one-stage technique which offers numerous attractive features for manufacturing multi applicable cell-laden hydrogel microcapsule for cell therapy and tissue engineering. Co-axial nozzle was applied to produce uniform core- shell microcapsule by electro spraying technique. Alginate (0.75 – 1.5 %w/v) was chosen as shell and various galantine-alginate blends (2.5, 5, 10, 20, 40 w/v gelatin to alginate) were selected as core materials. Some of important operation factors such as diameter of nozzles, voltage, flow rate of extrusion, and distance of gelling bath and nozzle were considered. The co-axial nozzle had a core tube with an inter diameter of 0.45 mm and a shell tube with an inter diameter of 0.9 mm. The results showed that increasing the flow rate of core to shell decreased shell thickness while uniformity of microcapsules was improved. In addition, the size of microcapsules decreased by rising voltage and reducing flow rate of core and shell extrusion. The results showed that the flow ratio of 4, applied voltage of 5.5 KV and distance of 2.5 cm could produce the uniform microcapsules with average diameters of 800 and 700 for shell and core, respectively. Cell growth analysis using osteoblast cells cultured by initial cell density 1.5 * 106 cell/ml in the cores depicted a 12.9 fold increase after 14 days, indicating that the core- shell microcapsules improved microenvironment for cell expansion. The present study demonstrated that core- shell microcapsules have high potential for using in tissue engineering bottom- up approach as building block for manufacturing organs and complicated tissue.