BACKGROUND: Drug treatment has unsatisfactory effect on Alzheimer disease, while many studies have indicated that the transplantation of bone marrow stromal cells (MSCs) is effective on Parkinson disease, cerebral ischemia, etc., but the mechanism is still unclear.OBJECTIVE: To imitate transplantation environment by co-culture of amyloid β1-40 (Aβ1-40) damaged PC12 cells and MSCs, observe the effect of bi-directional information feedback in the microenvironment on the transdifferentiation of MSCs to nerve cells, and observe its protective effect on the apoptosis of damaged PC12 cells.DESTGN: A comparative observation.SETTING: Department of Neurology, China Medical University.MATERIALS: SD rats of 2-3 weeks after birth either male or female were used. PC12 cell lines were purchased from the Institute of Cell Biology, Chinese Academy of Sciences; neuro-specific enolase (1:50, Boster, Wuhan);Methyl-thiazol-tetrazolium (MTT) 15 μL (terminal concentration of 0.5 g/L).METHODS: The experiment was carried out in the Experimental Center (provincial experimental animal center) of China Medical University from June to July in 2004. Bilateral femurs were aseptically removed from 1 SD rat, and MSCs were identified using CD44 antibody immunofiuorescently. PC12 was used to replace nerve cells. The PC12 cells were stimulated by Aβ1-40 then transferred by Transwell. There were 5 groups: Group A: normally cultured PC12 co-cultured with MSCs; Group B: Aβ1-40 stimulated PC12 co-cultured with MSCs; Group C: normal PC12 supernatant+MSCs; Group D: damaged PC12 supernatant+MSCs; Group E: MSCs cultured with common medium 1640.MAIN OUTCOME MEASURES:Routine immunohistochemical staining was performed. NSE positive cells were observed under inverted fluorescence microscope, 10 visual fields (200×) were randomly selected to count the positive cells. MTT metabolic rate was used to detect the proliferation of MSCs in each group. The differences of measurement data were compared using the one-way analysis of variance.fluorescent and bright fields, NSE positive cells appeared as red fluorescence, MSCs were bipolar, multipolar and cone shapes, and appeared as neuron-like forms with dendrite-like structure, and there were extensive connections among some neuron-like cells. The NSE positive rates was obviously higher in group B than groups A, C, D and E (P ＜ 0.01 ).in groups A, C, D and E (F=9.713, P＜ 0.01).

Objective To establish the co-culture system of marrow stromal cells (MSCs)and A?1-40 injured PC12 in vitro and to evaluate the effect and mechanisms of the system inhibiting apoptosis of PC12 induced by A?1-40.Methods MSCs and PC12 were cultured in vitro and identified by CD44 immunofluorescent staining;PC12 were damaged by A?1-40,and transferred by transwell followed by the classification into 5 groups. PI and Annexin-V co-fluorescent staining was performed,then PC12 apoptosis were detected by flow cytometry and EM;Supernatant was analyzed by enzyme-linked immunoadsordent assay (ELISA) to detected TGF-?,NGF,BDNF,and bFGF. Results About 96% MSCs showed CD44 positive cells. Co-culture group had the lowest rate of PC12 apoptosis(46.17%?8.28%,F=61.637,P0.05). Conclusion The co-culture system of MSCs and A?1-40 injured PC12 in vitro could inhibit apoptosis of PC12 induced by A?1-40. Thus grafted MSCs have the possibility to inhibit neuronal apoptosis by A?in the diseased brain.

Objective To develop a reversed phase high performance liquid chromatography ( RP￣HPLC) method determining the related substances and levidipine. Methods The Welchrom C18 column (250 mm×4.6 mm,5 μm) was used with Octadecylsilane bonded silica as a filler.The mobile phase consisted of methanol￣ethanol￣water (40:20:40),at the flow rate of 1 mL.min-1 in an isocratic elution,the temperature was at 45 ℃ , and the detective wavelength was 240 nm. Results Levidipine could be separated from all impurities and intermediates within the concentration range from151 to 604 ng.mL-1 , which had a satisfied linear relationship (r= 0.999 9) with a regression equation of Y= 0.049 9X+0.597 9.The LOQ of detection was 31.9 ng.mL-1 . Conclusion The developed method is specific,sensitive,easy and fast to operate,which is suitable for detecting levidipine and its related impurities.

Objective To establish a method for determination of the twelve residual organic solvents,including methanol,ethanol,acetone,isopropanol,tert-Butyl methyl ether,dichloromethane,aceticether,tetrahydrofuran,triethylamine,trimethylorthofor-Mate,morpholine,N,N-Dimethylformamide in Apixaban bulks drug.Methods Gas head-space chromatography was applied to this study.The column was DB-624 silica capillary column (30.0 m × 0.53 mm × 3.00 μm) and the carrier gas was high purity nitrogen;The vial temperature was 100 ℃,and the vial time was 20 min.The Column temperature was kept at 40 ℃ for 6 min,then the temperature was raised to 220 ℃ at the rate of 20 ℃/min and subsequently sustained for 10 min.FID detector temperature and injection temperature were both 250 ℃.The N2 flow rate was 2.8 mL/min.Split ratio was 5∶1.Results Twelve kinds of solvents were completely separated and determined with a good linearity (r =0.9994-0.9999).The RSD values of precision experiments and the average recovery was in line with the requirements.Conclusion Theanalytical method is simple,accurate and sensitive,which could be used for determination of residual organic solvents in Apixaban bulks drug.

To investigate the clinical features of patients with PLA2G6 gene related early onset Parkinson syndrome (EOP) with cerebellar atrophy, the clinical data of 3 hospitalized EOP patients with PLA2G6 gene mutation were collected in Xuanwu Hospital, Capital Medical University, and the clinical characteristics, imaging features and genetic testing results were comparatively analyzed. Related literatures were also reviewed. Cerebellar atrophy was observed on cranial magnetic resonance imaging in all 3 patients with Parkinson syndrome except for extrapyramidal symptoms. All 3 patients had heterozygous mutations of PLA2G6 gene, and the common mutation site of c.991G>T (p. D331Y) was found in 2 patients by second-generation sequencing. This report enlarges the clinical phenotypic spectrum of the disease and helps to better understand the disease.