Aim To research dynamically the changes of endogenous cystathionine- β-synthase/hydrogen sul-fide system in PC12 cells injury induced by rotenone. Methods Rotenone-induced injury in PC12 cells ( characteristic of dopaminergic neurons) was used as a PD cell model. The expression of CBS was evaluated by Western blot. Intracellular CBS activity and H2 S production were detected by Methylene blue spectro-phot-ometric method. The viability of PC12 cells was measured by CCK-8 assay. GSH detection kit was used to detect the intracellular GSH content. Results In the groups of 6 and 12 hours, the expression and activ-ity of CBS were elevated, and the production of H2 S was increased. In the groups of 24 and 48 hours, CBS expression and activity were significantly decreased, and the amount of H2 S was significantly reduced. Ap-plication of 1. 5 μmol·L-1 rotenone for different time (6-48h) could decrease the cell viability and intra-cellular GSH contents in a time-dependent manner. Conclusions The expression and activity of endoge-nous CBS, stimulated by rotenone, are elevated firstly and then decreased. The generation of H2 S, stimulated by rotenone, is increased and then reduced significant-ly, which may be related to PC12 cells against oxida-tive stress damage induced by rotenone.

Objective:To apply multiple mandibular anatomical landmark points to establish the mandibular median sagittal plane to find and establish the ideal median sagittal plane of the mandible that is suitable for clinical diagnosis and treatment.Methods:The maxillofacial spiral CT data of 30 normal maxillofacial patients in the Western Theater General Hospital were collected, and the 3D cranial model was reconstructed by using Mimics Research 21.0 software to select different anatomical landmarks to establish multiple mandibular MSPs, and with the whole cranial MSP as a reference, the different MSPs were respectively used as the mirror planes to establish a mirror model. The overlap of the original model and the mirror model were compared qualitatively and quantitatively by the overlap three-dimensional color illustration of 3-Matic software and Friedman′s test, respectively, to evaluate the application effect of different planes as mandibular MSPs.Results:There was a statistically significant degree of overlap between the mandibular mirror model and the original model with the whole head MSP and the different mandibular MSPs as mirror planes, respectively (χ 2=12.34, P<0.05). The mirror model of plane Mf-Go-Sim had the smallest overlap with the original model 0.07 (0.04, 0.18) mm; plane N-ANS-PNS was the second smallest 0.14 (0.09, 0.58) mm; the difference in overlap of plane ANS-SBWG-Mp 0.12 (0.04, 0.40) mm; the difference in overlap of plane Me-B-Sim 0.19 (0.09, 0.44) mm; the difference in overlap of plane Po-B-Go 0.18 (0.06, 0.45) mm. Conclusions:Whole-head MSP cannot completely replace mandibular MSP; plane Mf-Go-Sim can be the ideal MSP for the mandible in clinical applications.