Objectives To investigate whether degradation of anterior pharynx decfective-1(Aph-1) goes through proteasomal pathway or lysosomal pathway.Methods Various methods such as cell culture,Western blotting,pulse-chase metabolic labeling technique,double immunofluoresecnt staining,combined with proteasomal and lysosomal inhibition were used to check Aph-1 expression level in stable Aph-1-transfected or non-transfected neuronal(SH-SY5Y)cell line.Results Using Western blotting,treating the neuronal cells with proteasome specific inhibitors significantly increased the expression of both endogenous and exogenous Aph-1.The effect of the proteasome inhibitors on Aph-1 expression was dose-and time-dependent Lysosomal pathway was not involved in Aph-1 degradation. Pulse-chase metabolic labeling experiment showed that the turnover of newly-synthesized radiolabeled Aph-1 protein was blocked by Lactacystin.Double immunofluorescent staining revealed colocalization of Aph-1 and ubiquitin in the same cells.Conclusion Degradation of Aph-1 protein is mediated by proteasomal pathway in neuronal cells,and is not related to lysosomal pathway.Aph-1 protein is ubiquitinated before degradation.

During the teaching activities, to stimulate students' subject awareness and encour-age them to play the main role in class activities are inevitable trends in the reform of college educa-tion. Students’ subjective activity is a key to the teaching effect of regional anatomy, a course mainly based on experimental program. Department of Human Anatomy in Chongqing Medical University lay-outs regional anatomy teaching program to develop the students' subjective activities in learning from the course specialty: in preview and review, to train students' image-thinking by drawing; in anatomi-cal operation link, to cultivate students' interest in learning and innovation by discussing the relation-ship of anatomical structure and clinical disease and identifying the variation of structure; in the eval-uation process, taking the formative evaluation system to promote the students' initiatives and ensure the objectiveness and fairness. The implementation of these measures promotes the regional anatomy teaching quality.

Objective To investigate correlation between demyelination and caspase-12 expression alteration after compressed spinal cord injury (CSCI) so as to discuss mechanism of demyelinating lesion after CSCI.Methods Seventy-five adult SD rats were randomly divided into five groups,ie,normal group,control group,compression 1 d,3 d and 7 d groups,with 15 rats per group.Models of spinal cord compression were established with a self-made device.Ultrastructure of the demyelinated nerve fibers was observed by electronic microscope and oligodendrocyte apoptosis was detected by TUNEL staining and double labeling immunofluorescence.Immunoblotting was used to defect caspase-12 that was related to cell apoptosis.Results Demyelination of nerve fiber occurred after CSCI and was aggravated with time.Apoptosis of oligodendrocytes was found after CSCI,and showed significant difference between compression 7 d group and normal group (P ＜ 0.05).Caspase-12 was also upregulated with extension of compression time.Conclusion Caspase-12 mediating oligodendrocyte apoptosis is one of the mechanisms of nerve fiber demyelination after CSCI.

Objective To investigate the role of demyelination and the alteration of chondrotin sulfate proteoglycan (CSPG,NG2) expression after compression injury of the spinal cord (CSCI).Methods Seventy-five adult Sprague-Dawley rats were randomly divided into a normal group,a sham-operation group,a CSCI 1 day group,a CSCI 3 day group,and a CSCI 7 day group.There were 15 rats in each group.The injuries in the CSCI groups were inflicted using a technique devised in our laboratory.Basso-Beattie-Bresnahan (BBB) neurological function assessment was used to assess the rats' motor function,osmic acid staining and transmission electronic microscopy (TEM)were used to observe any pathological changes of myelinated nerve fibers in the white matter at 1,3 and 7 days after CSCI.The amount of myelinated nerve fibers in the posterior funiculus of the spinal cord and the ratio of myelin sheath thickness to axon diameter (the G-ratio) were calculated.Any alteration in NG2 expression was observed by Western blotting.Results The average neurological function assessment scores in the CSCI groups were (1.23 ±0.45),(0.65 ± 0.35) and (0.00 ± 0.00) respectively.Compared with the normal group (21.00 ± 0.00) and the sham operation group (21.00 ± 0.00),the differences were all statistically significant.The rats' motor function deteriorated gradually with time after the CSCI.Osmic acid staining showed that the white matter was intact in the normal and sham groups.After being compressed the myelinated nerve fibers became swollen,degenerated and broke down.The amount of myelinated nerve fibers in the normal group,the sham operation group and the three CSCI groups was (2771 ± 108),(2675 ± 199),(2403 ± 161),(1708 ± 70) and (8 10 ± 95) respectively.The amount of myelinated nerve fibers decreased in the CSCI groups and reached a minimum on the 7th day.The difference was statistically significant.The TEM quantity analysis showed that the G-ratios in the normal,sham operation,and CSCI 1 day,3 day and7 day groups were (18.10±0.4),(17.70±1.0),(6.69 ±0.8),(5.73 ±0.4) and (4.95 ±0.5) respectively.Compared with the normal and sham operation groups,the G-ratios in the 3 CSCI groups were lower and reached their minimum on the 7th day after injury.The difference was statistically significant.TEM observation showed that the axons and myelin sheaths were intact in the normal and sham groups.After CSCI the axons became swollen and cell organelles in the axoplasm degenerated and decreased.The layers of myelin sheath shrank,folded and even wrinkled,which had an onion-like appearance.The oligodendrocytes exhibited chromatin condensation.Macrophages showed infiltration.Western blotting showed that the expression of NG2 in the CSCI groups reached a maximum on the 1st day after injury and then decreased with time.The expression of NG2 in the CSCI groups was higher than in the normal and sham groups,and the difference was statistically significant.Conclusion Demyelination occurs after CSCI-the amount of myelinated nerve fibers decreases and neurological deficits increase with time.The expression of NG2 was associated with changes in the myelin sheaths after CSCI and contributed to recovery of the myelin sheath through proliferation and differentiation to oligodendrocytes and perhaps other kinds of cells.

It is extremely necessary and important for colleges or universities to transform the education concepts that barricade students' initiative and creativity, especially the one that takes fi-nal examinations as sole standard to evaluate teaching and learning effects. In order to display and cultivate students' study ability more comprehensively, we manage to establish a set of formative eval-uation system for regional anatomy course , which involves tests and examinations and evaluations throughout the whole teaching and learning process. It solves the long-lasting problem that examina-tions are final purposes of teaching and learning, and thus, teaching values not only results but also learning process, which directs students' attention to conventional studies and helps develop good study habits, greatly reducing the randomness of final academic performances. The diverse assessment methods, along with accumulated assessment results, can improve students' learning effects through-out the whole semester. The fundamental purpose of this system is to inspire students' passion for study and creativity and monitor the teaching process.

It is an important way to improve the teaching quality by carrying out innovative experiments among medical students. In the process of experimental teaching, anatomy teachers expand the anatomy knowledge to basic scientific research techniques, so as to enhance students' confidence in participating in innovative experimental projects. Meanwhile, the teachers combine introduction of the anatomical structures with hot medical research issues, in order to help students to select appropriate innovative experimental topics. What's more, the new media teaching is integrated into the teaching of anatomy, enlightening students to perfect the experimental designs. Finally, in the teaching practice of regional anatomy, students are guided to carry out innovative experiments and write research papers. Abovementioned measures not only improve the teaching quality of anatomy, but also improve the students' scientific research ability, laying a foundation for them to participate in innovative experimental projects.