Embryonic mesenchymal stem cells (eMSCs) were first derived from human embryonic stem cells (hESCs) overexpressing green fluorescence protein (GFP). They expressed CD29, CD44, CD73, CD105, CD166 and nestin, but not CD34, CD45, CD106 SSEA-4 or Oct3/4. Twenty million eMSCs in 1 mL of phosphate-buffered saline (PBS) were injected into the femoral veins of spontaneously hypertensive rats after transient middle cerebral artery occlusion. The migration and differentiation of the eMSCs in the ischemic brain were analyzed. The results revealed that eMSCs migrated to the infarction region and differentiated into neurons, which were positive for b-tubulin III, microtubule-associated protein 2 (MAP2), HuC, neurofilament and human nuclear antibody, and to vascular endothelial cells, which were positive for von Willebrand factor (vWF). The transplanted cells survived in the infarction region for at least 4 weeks. Adhesive removal function significantly improved in the first week after cell transplantation, and rotarod motor function significantly improved starting from the second week. The infarction volume in the eMSC group was significantly smaller than that in the PBS control group at 4 weeks after infusion. The results of this study show that when administered intravenously, eMSCs differentiated into neuronal and endothelial cells, reduced the infarction volume, and improved behavioral functional outcome significantly in transient focal cerebral ischemia.

Object The aim of this study was to describe the microsurgical anatomy of the orbitozygomatic craniotomy and its modifications, and detail the stepwise dissection of the temporalis fascia and muscle and explain the craniotomy techniques involved in these approaches. Methods Nine cadaveric embalmed heads injected with colored silicone were used to demonstrate a stepwise dissection of the 3 variations of orbitozygomatic craniotomy. The craniotomies and dissections were performed with standard surgical instruments, and the microsurgical anatomy was studied under microscopic magnification and illumination. Results The authors performed 2-piece, 1-piece, and supraorbital orbitozygomatic craniotomies in 3 cadaveric heads each. Stepwise dissection of the temporalis fascia and muscle, and osteotomy cuts were shown and the relevant microsurgical anatomy of the anterior and middle fossae was demonstrated in cadaveric heads. Surgical case examples were also presented to demonstrate the application of and indications for the orbitozygomatic approach. Conclusions The orbitozygomatic approach provides access to the anterior and middle cranial fossae as well as the deep sellar and basilar apex regions. Increased bone removal from the skull base obviates the need for vigorous brain retraction and offers an improved multiangled trajectory and shallower operative field. Modifications to the orbitozygomatic approach provide alternatives that can be tailored to particular lesions, enabling the surgeon to use the best technique in each individual case rather than a “one size fits all” approach.

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Although various posterior insertion angles for screw insertion have been proposed for C1 lateral mass, substantial conclusions have not been reached regarding ideal angles and average length of the screw yet. We aimed to re-consider the morphometry and the ideal trajections of the C1 screw. Morphometric analysis was performed on 40 Turkish dried atlas vertebrae obtained from the Department of Anatomy at the Medical School of Ankara University. The quantitative anatomy of the screw entry zone, trajectories, and the ideal lengths of the screws were calculated to evaluate the feasibility of posterior screw fixation of the lateral mass of the atlas. The entry point into the lateral mass of the atlas is the intersection of the posterior arch and the C1 lateral mass. The optimum medial angle is 13.5 +/- 1.9 degrees and maximal angle of medialization is 29.4 +/- 3.0 degrees . The ideal cephalic angle is 15.2 +/- 2.6 degrees , and the maximum cephalic angle is 29.6 +/- 2.6 degrees . The optimum screw length was found to be 19.59 +/- 2.20 mm. With more than 30 degrees of medial trajections and cephalic trajections the screw penetrates into the spinal canal and atlantooccipital joint, respectively. Strikingly, in 52% of our specimens, the height of the inferior articular process was under 3.5 mm, and in 70% was under 4 mm, which increases the importance of the preparation of the screw entry site. For accommodation of screws of 3.5-mm in diameter, the starting point should be taken as the insertion of the posterior arch at the superior end of the inferior articular process with a cephalic trajection. This study may aid many surgeons in their attempts to place C1 lateral mass screws.