A novel simulator-based checklist for evaluating residents' competence in cerebral angiography in China.

Background: Nowadays, with the fast-increasing demand for neuro-endovascular therapy, surgeons in this field are in urgent need. Unfortunately, there is still no formal skill assessment in neuro-endovascular therapy in China. Methods: We used a Delphi method to design a newly objective checklist for standards of cerebrovascular angiography in China and evaluated its validity and reliability. A total of 19 neuro-residents with no interventional experience and 19 neuro-endovascular surgeons from two centers (Guangzhou and Tianjin) were recruited; they were divided into two groups: residents and surgeons. Residents completed a simulation-based cerebrovascular angiography operation training before assessment. Assessments were under live and video record forms with two tools: the existing global rating scale (GRS) of endovascular performance and the new checklist. Results: The average scores of residents were significantly increased after training in two centers (p < 0.05). There is good consistency between GRS and the checklist (p = 0.856). Intra-rater reliability (Spearman's rho) of the checklist was >0.9, and the same result was also observed in raters between different centers and different assessment forms (p < 0.001, rho > 0.9). The reliability of the checklist was higher than that of the GRS (Kendall's harmonious coefficient is 0.849, while GRS is 0.684). Conclusion: The newly developed checklist appears reliable and valid for evaluating the technical performance of cerebral angiography and differentiating between trained and untrained trainees' performance well. For its efficiency, our method has been proven to be a feasible tool for resident angiography examination in certification nationwide.

Loss of GFAP and Vimentin Does Not Affect Peri-Infarct Depolarizations after Focal Cerebral Ischemia.

Peri-infarct depolarization (PID), one kind of spreading depolarization, contributes to infarct volume enlargement after ischemic stroke. Astrocytes participate in PIDs by various mechanisms. The roles of glial fibrillary acidic protein (GFAP) and vimentin (Vim), intermediate filament proteins in astrocytes, however, in PIDs induction and propagation remain unknown. Middle cerebral artery occlusion (MCAO) model was made in 9 GFAP-/-Vim-/- and 9 wild-type (WT) C57BL/6 mice. Using 4-wavelength optical intrinsic signal imaging (OIS), we identified PIDs as consistent, red and blue interaction waves in the cortical reflectance that slowly propagated peripherally from the origin site. Five propagation patterns of PIDs were observed after MCAO in mice, namely, latero-medial, medial-lateral, rostro-caudal, caudo-rostral, and collision. Additionally, the frequency, propagation velocity, and duration of PIDs between GFAP-/-Vim-/- and WT mice were not significantly different (p > 0.05). Furthermore, no significant difference was found in infarct volume and brain edema between the two groups. In conclusion, the 4-wavelength OIS system allows acquisition of high temporal-spatial resolution color images for analyzing temporal-spatial characteristics of PIDs in detail. GFAP and Vim in astrocytes are not involved in PIDs after MCAO in mice.

An analysis of related factors of surgical results for patients with craniopharyngiomas.

OBJECTIVE: The objective of this study was to retrospectively review the surgical results following gross total resection and partial resection with or without radiotherapy for craniopharyngiomas and analyze the related factors of surgical results. METHODS: From 1994 to 2009, 214 patients underwent 219 procedures for craniopharyngiomas. We retrospectively reviewed the pre- and postoperative data of patients, reported the perioperative and long-term surgical results and analyzed the influencing factors and the relationship between hypothalamic involvement and postoperative quality of life. RESULTS: Gross total resection was achieved in 154 procedures (70.3%). Perioperative mortality was 5%. Perioperative hyperpyrexia was the most significant risk factor for perioperative mortality. A total of 151 patients were followed from 6 months to 190 months. There were significant differences in recurrence rate and overall survival between gross total resection and limited resection (P<0.05). There was significant difference in recurrence rate between limited resection and limited resection with radiotherapy (P<0.01), but it did not reach statistical difference between gross total resection and gross total resection with radiotherapy. The factors strongly influencing overall survival include old patients, partial resection and recurrent tumors. The preoperative hypothalamic involvement negatively correlates with the postoperative quality of life in patients with craniopharyngiomas. CONCLUSION: The preoperative CT/MR imaging provides clues of the relationship between tumor and surrounding structures. Gross total resection should be achieved in the treatment of craniopharyngiomas on the condition that hypothalamus is preserved. The patients who undergo limited resection should receive conventional radiotherapy or gamma knife surgery.

GSK-3ß activation mediates Nogo-66-induced inhibition of neurite outgrowth in N2a cells.

The axons of the adult mammalian brain and spinal cord fail to regenerate after injury, and it has been suggested that Nogo-66 could prevent CNS axon repair. However, the mechanism of Nogo-66 inhibiting neurite outgrowth remains unknown. Our previous results indicated that protein kinase B (PKB) is involved in the inhibition of the neurite outgrowth by Nogo-66. Glycogen synthase kinase-3ß (GSK-3ß) is implicated in many processes in the nervous system, including differentiation, specification, polarity, plasticity and axon growth. In addition, GSK-3ß is one of the most important molecules downstream of PKB. In the present study, we report on the role of GSK-3ß signaling on Nogo-66-treated mouse neuroblastoma N2a cells. Nogo-66 reduced the phosphorylation of GSK-3ß at Ser9 in N2a cells. In contrast, pretreatment with SB216763, a specific inhibitor of GSK-3ß, resulted in an amelioration of neurite outgrowth by Nogo-66, compared with the Nogo-66 alone group (P<0.05). Moreover, we performed RNA interference experiments to knock down GSK-3ß expression levels in N2a cells via transient transfection of shRNA plasmids. The inhibition of neurite outgrowth by Nogo-66 was subdued in shRNA cells, compared to the non-RNAi cells (P<0.05). Taken together, these data suggest that GSK-3ß is involved in the inhibition by Nogo-66 of neurite outgrowth in N2a cells.

Expression of PirB in normal and injured spinal cord of rats.

The expression of paired immunoglobulin-like receptor B (PirB) in normal and injured spinal cord of rats was investigated. The SD rat hemi-sectioned spinal cord injury (SCI) model was established. Before and 1, 3, 7, 10 days after SCI, the spinal cord tissues were harvested, and Western blot and immunohistochemistry were used to examine the expression and location of PirB. The results showed that the expression level of PirB in the normal spinal cord of SD rats was low. At the first day after SCI, the expression of PirB was obviously increased, and that in the injured spinal cord from the first day to the 10th day was significantly higher than in the normal spinal cord. The positive expression of PirB in neurons from different regions of gray matter of the injured spinal cord was seen. It was concluded that the expression of PirB in the normal spinal cord of rats was low. The expression of PirB in SCI was significantly increased till at least the 10th day.