Human umbilical cord-derived Schwann-like cell transplantation combined with neurotrophin-3 administration in dyskinesia of rats with spinal cord injury.

Mesenchymal stem cells are capable of differentiating into Schwann-like cells. In this study, we induced human umbilical-cord mesenchymal stem cells (HUMSCs) in vitro into neurospheres constituted by neural stem-like cells, and further into cells bearing strong morphological, phenotypic and functional resemblances with Schwann-like cells. These HUMSC-derived Schwann-like cells, after grafting into the injured area of the rats' spinal cord injury (SCI), showed a partial therapeutic effect in terms of improving the motor function. Neurotrophin-3 (NT-3) was reported to improve the local microenvironment of the grafted cells, and we, therefore, further tested the effect of Schwann-like cell grafting combined with NT-3 administration at the site of cell transplantation. The results showed that NT-3 administration significantly promoted the survival of the grafted cells in the host-injured area. Significant improvement in rats treated by Schwann-like cell grafting combined with NT-3 administration was demonstrated in the behavioral test as compared with that in animal models received the cell grafting only. These results suggest that transplantation of the Schwann-like cells combined with NT-3 administration may represent a new strategy of stem cell therapy for spinal cord injury.

Construction of a mouse pDsRed2-N1-SDF-1alpha eukaryotic expression vector and its expression in mouse bone marrow mesenchymal stem cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To construct the eukaryotic expression vector pDsRed2-N1-SDF-1alpha and observe its expression in the mouse bone marrow mesenchymal stem cells.</p><p><b>METHOD</b>SDF-1alpha gene sequence with XhoI, EcoRI restriction enzyme cutting site was amplified from the total RNA of mouse smooth muscle cells by reverse transcription-polymerase chain reaction (RT-PCR) and inserted into the eukaryotic expression vector pDsRed2-N1 encoding red fluorescent protein gene, and the insertion was verified by endonuclease digestion and DNA sequencing. Mouse bone marrow mesenchymal stem cells identified with immunofluorescence assay for vimentin expression were transfected with the constructed plasmid pDsRed2-N1-SDF-1alpha, and the expression of sdf-1alpha was detected using immunofluorescence assay.</p><p><b>RESULTS</b>The DNA fragment amplified by PCR from the total RNA was identical to SDF-1alpha from the gene library, and an identical DNA fragment was also amplified from the recombinants. Sequence analysis confirmed the successful insertion of SDF-1alpha into the pDsRed2-N1 vector and the eukaryotic expression vector pDsRed2-N1-SDF-1alpha was successfully constructed. The cultured mouse bone marrow mesenchymal stem cells positive for vimentin protein showed SDF-1alpha expression 24 h after transfection with the recombinant vector.</p><p><b>CONCLUSION</b>The pDsRed2-N1-SDF-1alpha eukaryotic expression vector constructed is capable of expression of SDF-1alpha fusion protein in the mouse bone marrow mesenchymal stem cells.</p>

Culture and identification of neural stem cells derived from the subventricular zone of adult mice / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish a method for culturing and identifying neural stem cells (NSCs) derived from the subventricular zone (SVZ) in adult mice.</p><p><b>METHODS</b>NSCs were isolated from the SVZ of adult mouse brain and cultured in serum-free medium. Cell cloning and BrdU incorporation were performed to identify the self-renewal and proliferative capacity of the NSCs. Fluorescence immunocytochemistry was used to examine the expressions of the NSC markers nestin and SOX2, neuronal marker Tuj1, astrocyte marker GFAP and oligodendrocyte marker NG2. The expressions of nestin and SOX2 were further examined by Western blotting and RT-PCR.</p><p><b>RESULTS</b>NSCs with self-renewal and proliferative capacity were obtained from the SVZ of adult mice and grown as floating neurospheres. The NSCs expressed nestin and SOX2 and could differentiated into Tuj1-positive neurons, GFAP-positive astrocytes and NG2-positive oligodendrocytes.</p><p><b>CONCLUSION</b>This method allows simple and stable culture of NSCs from the SVZ of adult mice.</p>

Application of virtual imaging technique in diagnosis of intracranial aneurysms / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the value of virtual imaging technique in diagnosis of intracranial aneurysms.</p><p><b>METHODS</b>Fifty-four cases of 54 intracranial aneurysm diagnosed by three-dimensional CT angiography (3D-CTA) examinations were enrolled in this study. Three-dimensional virtual images of the skull and cerebral vessels were acquired by three-dimensional reconstruction of the original CT images using the surgical planning system, and the location, size and shape of the aneurysms and their anatomical relationship with the adjacent tissues were observed and measured from several angles. All the patients underwent surgical planning and simulated surgical operations using the virtual surgical instruments available in the system.</p><p><b>RESULTS</b>All the 54 cases had successful three-dimensional virtual image reconstruction and the surgical planning operations. The virtual imaging system generated clear and vivid three-dimensional virtual images which clearly visualized the location and size of the aneurysms and their precise anatomical relations to the parent arteries and skull. This virtual reality imaging system also allowed simulation of simple surgical procedures.</p><p><b>CONCLUSION</b>The surgical planning system based on the virtual reality imaging can serve as a useful means to assist the diagnosis and provide precise imaging details of intracranial aneurysms.</p>

Combined application of virtual imaging techniques and three-dimensional computed tomographic angiography in diagnosing intracranial aneurysms / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The diagnostic value of virtual imaging combined with three-dimensional computed tomographic angiography (3D-CTA) for intracranial aneurysms has not been fully elucidated yet. This study aimed to evaluate the value of combined application of virtual imaging techniques and 3D-CTA in diagnosing patients with aneurismal subarachnoid hemorrhage (SAH) at the acute stage.</p><p><b>METHODS</b>Eighty patients with non-traumatic SAH received 3D-CTA examinations. The raw CT data of these patients were reconstructed and transferred into the 3D mode through the surgical plan system based on virtual reality (VR) image, and the 3D virtual images of skulls and brain blood vessels were acquired. The location, size and shape of aneurysms and their anatomic relationship with adjacent tissues were measured from many points of view.</p><p><b>RESULTS</b>Seventy-three aneurysms were detected in 68 of the 80 patients, but 2 aneurysms were detected in 2 of the 5 patients who had been found free of aneurysms previously and had received 3D-CTA examinations for a second time one month later. The 3D virtual images produced by the virtual imaging system were clear and vivid, and they could reveal the location and size of the aneurysm and its relations to the parent artery and skull directly.</p><p><b>CONCLUSIONS</b>The imaging of 3D-CTA is convenient, reliable and fast in diagnosing intracranial aneurysms and can be regarded as the first choice for the diagnosis and treatment of ruptured intracranial aneurysms. Combined with the surgical plan system based on the VR image, 3D-CTA may obtain more imaging information about aneurysms.</p>

Time course of calpain activity changes in rat neurons following fluid percussion injury and the interventional effect of mild hypothermia / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the time course of calpain activity changes in rat neurons following fluid percussion injury (FPI) under normothermia (37 degrees celsius;) and mild hypothermia (32-/+0.5) degrees celsius;.</p><p><b>METHODS</b>In vitro cultured rat neurons were subjected to FPI followed by application of mild hypothermia for intervention at different time points, and the changes in intraneuronal calpain activity following FPI and the interventional effect of mild hypothermia on calpain activity were evaluated by UV-spectrophotometry at different time points.</p><p><b>RESULTS</b>Remarkable changes occurred in calpain activity in the neurons following FPI at 37 degrees celsius;, and mild hypothermia produced obvious interventional effect on calpain activity in close relation to the timing of intervention initiation.</p><p><b>CONCLUSION</b>Intraneuronal calpain activity changes following FPI are involved in the pathological process of cellular injury, and mild hypothermia might offer protection against traumatic brain injury to some extent by regulating calpain activity. The interventional effect of mild hypothermia is associated with the timing of the intervention initiation.</p>