Objective To explore the effect of glial cell line-derived neurotrophic factor(GDNF) on the expressing of calbindin D28K(CB) in substantia nigra(SN) of rat model of Parkinson's disease(PD) and the possible role of neural cell adhesion molecule(NCAM) in this course.Methods 36 rat models of PD were made,and divided into GDNF group,NCAM blocked group and control group(each group had 12 rats).Immunohistochemistry and Western blot method were used to detect the number of CB-positive cells and the expressed level of CB protein in SN of rats.Results The number of CB-positive cells(46.50?6.28) and the expressed level of CB protein(33770.60?6929.76) in SN of GDNF group were significantly higher than control group [(27.00?8.60),(18281.00?5266.78) respectively](all P0.05).Conclusions GDNF may protect the injured dopaminergic neurons through up regulating the expressing of CB,but NCAM is not involved in this mechanism.

Objective To investigate the changes of dopaminergic(DA) neurons in substantia nigra compact of the aged rats.Methods Using RT-PCR,Western blot,immunohistochemistry and electron microscope to detect the levels of TH mRNA and TH protein,the number and the ultrastructure of TH-positive neurons in the substantia nigra compact of the aged rats(≥24 months),and comparing those with adult rats(4～5 months).Results The level of TH mRNA(0.66?0.12) in substantia nigra compact of the aged rats was much lower than that in the adult rats(1.09?0.08)(P0.05).However,the number of TH-positive neurons in the caudal of substantia nigra compact of the aged rats was much lower than that of the adult rats(P

Gene therapy refers to the introduction of normal genes into human target cells for correcting gene defects or exerting therapeutic action,and thus achieves the goal of treatment of disease.Bone marrow stromal cells (BMSCs) are stem cells that possess self-renewal and multi-directional differentiation potential and easy to amplify in vitro,and they also express many therapeutic exogenous genes in vitro or in vivo.So BMSCs have been regarded as an ideal target cell of cell and gene therapy.This article reviews the biological characteristic of BMSCs,some commonly used gene therapy vectors and their applications in gene therapy of central nervous system diseases.

Translational medicine emerging as a new concept in medical field, concentrates on the integration of theory and practice , and the conjunction of basic medical science and clinical medicine. Barriers between the basic medicine and clinical medicine existing in medical education in China make students possess limited intelligence, narrow perspectives and low creativity etc., causing the medical teaching unable to conform to the demand of translational medicine. The article introduces the basic conception of translational medicine and the necessity of medical teaching reform, the meth-ods of promoting teaching reform by integrating the curriculum systems, bettering experimental teach-ing systems, strengthening humanities education, improving faculty construction and optimizing eval-uation system for students.

Objective To investigate the effect of dexcedetomidine on the postoperative delirium in adolescent idiopathic scoliosis undergoing spine surgery. Methods 160 patients (7-16 years of age) with idiopathic scoliosis undergoing posterior spinal fusion were randomly divided in to two groups. Group SS (n=80) included patients anesthetized with sevorane and sufentanil, group SSD (n=80) included patients anesthetized with sevorane,sufentanil and dexcedetomidine. In the latter group, dexcedetomidine was administered as a continuous infusion of 0.2 ug/h started after the induction of anesthesia without a loading dose. Sevorane was adjusted to maintain the bispectral index (BIS) number at 40-60 and vasoactive drugs was adjusted to maintain the mean arterial pressure (MAP) at 65-75 mmHg. The amount of anesthetic, the time of anesthesia recovery,restlessness during recovery and postoperative delirium were recorded. Results The amount of sevorane, the incidence of restlessness during recovery and the incidence of postoperative delirium were significantly lower in the group SSD than in group SS ( <0.05) . Conclusion The perioperative infusion of 0.2 ug/h dexcedetomidine can decrease the incidence of postoperative delirium in adolescent idiopathic scoliosis undergoing spine surgery.

Objective To explore the proliferative changes and clinical significance of osteoclasts (OC) in various stages of osteoarthritis (OA). Methods Twenty healthy adult male SD rats were made the model by modified Hulht procedure,the left knee served as the control group and the right knee as the OA model group. The total knee joint (n=5) was collected at postoperative 1, 2,4,8 weeks, fixed at 4 ℃ 4% poly formaldehyde (PFA) liquid, embedded by paraffin for conducting sections, and stained by TRAP,toluidine blue(TB) and safranine O (Saf O)fast staining. Then the cartilage morphology change was observed and OC positive cells number with TRAP staining were semi-quantitatively detected,the OA cartilage destruction progression was evaluated by Mankin's method and SPSS17.0 statistics software was used to conduct statistical analysis. Results OC in the two groups showed the transient change of rapidly increasing and then decreasing. The OC number at 1 week in the control group (left knee) was (65.20±4.12) cells/mm2 ,and was gradually reduced at 2,4 weeks,which were (47.20±4.31) cells/mm and (26.20±3. 87) cells/mm2 ,which at 8 weeks was almost invisible, the number of cells was (7.00 ± 2.28) cells/mm2 ;the OC number at 1 week in the OA model group (right knee) was (70.40 ± 5.46) cells/mm2 ,increased to (86.20± 5.42)cells /mm2 at 2 weeks, reduced to (38. 0 ± 3.16) cells/mm2 at 4 weeks , was almost invisible at 8 weeks, the number of cells was (6.21 ± 2.93 ) cells/mm2 . The OC number at 2,4 weeks in the model group was significantly higher than that in the control group, the difference had statistical significance (P<0.05). Conclusion Large numbers of osteoclasts are proliferated in the early and middle stages of rat knee osteoarthritis, which indicating that OC might be involved in the formation of osteoarthritis.

Objective To explore the risk factors of osteoporosis in elderly patients with ischemic stroke by intracranial atherosclerotic stenosis(ICAS). Methods 342 elderly patients(≥ 65 year)with ischemic stroke by ICAS were divided into osteoporosis group and non-osteoporosis group,multivariate unconditional Logistic re-gression analysis was used to analyze the risk factors for elderly patients with ischemic stroke by ICAS. Results Univariate analysis shows that female,unilateral anterior circulation infarct,involvement of vessels of more than two branches,complete paralysis,delayed paralysis,BI index were significantly associated with osteoporosis in el-derly patients with ischemic stroke by ICAS between the two groups(all P < 0.05). Multiple Logistic regression analysis revealed that gender,disease duration,involvement of cerebral circulation,paralysis degree,muscle ten-sion state were independent risk factors for the development of osteoporosis in elderly patients with ischemic stroke by ICAS(OR = 3.459,2.486,4.540,3.819,3.699,P < 0.05). Conclusions Gender,disease duration,in-volvement of cerebral circulation,paralysis degree,muscle tension state are independent risk factors of osteoporo-sis in elderly patients with ischemic stroke by ICAS,provides a theoretical basis for the prevention of osteoporosis in elderly patients with ischemic stroke by ICAS.

Objective:To investigate the effect of Lamins B2 (LMNB2) on the migration of human retroperitoneal liposarcoma (RPLS) cells SW872.Methods:Immunohistochemistry was used to analyze the the differential expression levels of LMNB2 in 33 RPLS tissue samples . The correlation between LMNB2 expression and clinical prognosis and clinicopathological features was analyzed. siRNA was used to lower the expression level of LMNB2 in tumor cells, and the effect of LMNB2 on the scratch healing ability and migration ability of SW872 cells was examined by using wound-healing assay and transwell migration assay. The expression levels of p-AKT and AKT in each group cells were detected by Western blot.Results:Patients with high LMNB2 expression had a lower recurrence-free survival and overall survival compared to those with low LMNB2 expression, and were more likely to experience recurrence, ( χ2=4.872, P=0.027; χ2=4.180, P=0.041; χ2=7.127, P=0.008). The migration ability of cells was significantly reduced following the silencing of LMNB2 expression ( t=11.240, P<0.01; t=7.445, P<0.01). The expression level of p-AKT in the silencing group was significantly lower than that in the control group, while there was no significant difference in the expression level of AKT between the two groups ( t=9.784, P<0.01). Conclusion:LMNB2 may promote the migration of human retroperitoneal liposarcoma cells SW872 by regulating AKT signaling pathway.

Objective:To investigate the CT imaging features of fat-poor primary retroperitoneal liposarcoma ( PRPLS).Methods:The CT signs of 43 fat-poor PRPLS cases among 128 PRPLS patients confirmed by pathology, including multiple nodules composing or multiple nodules fusing, tumor heterogeneity, were retrospectively evaluated.Results:Of 43 fat-poor PRPLS cases, 28 cases(65%) showed multiple nodules composing or multiple nodules fusing on CT images, 15 cases (35%)demonstrated single mass. Seventeen cases showed tumor heterogeneity on pre-contrast scan, 18 cases showed tumor heterogeneity on contrast scan, 13 cases showed tumor heterogeneity on both pre-contrast and contrast scan, 22 cases (51%)showed tumor heterogeneity on pre-contrast or contrast scan.Conclusion:CT signs of multiple nodules composing or multiple nodules fusing, especially tumor heterogeneity may help establishing diagnosis of fat-poor PRPLS.

Objective:To explore the clinical diagnosis and treatment methods and curative effect of retroperitoneal ganglioneuromaMethods:The clinical data of 32 cases of retroperitoneal ganglioneuroma admitted to Peking University International Hospital from Apr 2015 to May 2022 were retrospectively analyzed, and their clinical characteristics, surgical efficacy and prognosis were discussed.Results:Of the 32 patients with retroperitoneal ganglioneuroma, 17 had no obvious clinical symptoms, 7 complained abdominal distension and pain, 6 had lower back pain, and 2 had abdominal mass. Tumors were located near the adrenal and renal regions in 18 cases, on both sides of the spine below the kidneys in 11 cases, and in the pelvis in 3 cases. tumors were single in 28 cases, multiple in 4 cases.Tumors were surrounded by major blood vessels in 12 cases. R 0 or R 1 resection was carried out in 27 cases, and palliative R 2 resection in 5 cases, combined organ resection in 6 cases, and piecemed resection in 8 cases. The maximum tumor diameter was (13.2±4.9)cm, the intraoperative blood loss was 500 (50-6 000 ml), and 6 cases suffered from major postoperative complications. Between patients with tumors encircling and encroaching major blood vessels or not, there were significant differences in age, intraoperative blood loss, R 2 resection rate, and pieceneal resection rate between the two groups ( t=2.44, P=0.021; Z=2.37, P=0.018; χ2=4.57, P=0.033; χ2=11.38, P=0.001). There was no recurrence in patients with R 0 or R 1 resection. Conclusions:The prognosis of complete resection of retroperitoneal ganglioneuroma is good .Major blood vessels encroachment of the tumor often leads to incomplente (R 2) resection.