Objective To investigate the effect of exogenous vascular endothelial growth factor (VEGF) on bone activity of rabbit heterotopic allograft decalcified bone.Methods 140 adult healthy China white rabbits were selected,no limitation with sex,20 rabbits as the donor preparation of allogenic decalcified bone,according to the random number table,the rest was divided into the experimental group (allograft decalcified bone ± VEGF) and the control group (Allograft decalcified bone),each group contained 60 rabbits.For the experimental group,the prepared 1.5 cm long homologous decalcified tibia was placed in rabbit right thigh of rectus femoris and vastus medialis muscle gap near by saphenous artery,and fixed on the femur with two 0.8 mm Kirschner wire.In the vicinity of the skin,implanted an osmotic pump which contain the VEGF solution 200 μl with concentration was 0.5 μg/ml.In the control group,implanted the isometric allograft decalcified bone in rabbit right thigh corresponding parts with the same method.Each group respectively at 0,2,4,6,8,10 weeks to death 10 white rabbits,By specimen observation,HE dyeing observation and detection of type Ⅰ glue protein fluorescence intensity,Analysis the bone activation degree of two groups of bone allograft decalcified.Results Experimental allograft decalcified bone gradually wrapped by connective tissue membrane,its surface appear different size of the pits and gradually increased and become deep,while the control group pits relatively little and shallow.In the experimental group and control group,the fluorescence intensity of type Ⅰ collagen reached its peak respectively at 8 weeks (47.57 ±3.50) and 10 weeks (45.07±6.02),with no statistically significant (P ＞ 0.05).Conclusion Rabbit allograft decalcified bone implanted in the muscle clearance with abundant blood supply can be transformed into activated bone after 10 weeks,and after applying exogenous VEGF,allograft decalcified bone can be transformed into activated bone after 8 weeks,the bone activation process obviously speed up.The reaults confirmed the exogenous VEGF can obviously promote the ectopic rabbit bone allograft decalcified bone activation process.

Objective To develop a clinically useful assay for detecting the mutations of HBV pre-C/BCP based on the pyrosequencing and accuracy, reproducibility and reliability of this assay was evaluated. Methods The pyrosequencing primers for HBV pre-C/BCP mutation were designed through the cluster analysis among one hundred HBV gene sequences. After the amplification of the fragment of pre-C/BCP with the template of pre-C/BCP mutation plasmids, the pyrosequencing method for pre-C/BCP detection was initially set up with this standard sample. The accuracy, reliability and reproducibility of the pre-C/BCP pyrosequencing were confirmed through the pre-C/BCP plasmids as a standard sample when compared with Sanger/genechip sequencing method pre-C/BCP pyrosequencing assay was applied for detecting pre-C/BCP mutation types of 60 chnical serum samples in HBV patients. Results The pre-C/BCP mutation detection assay based on pyrosequencing has been established in our study. The coincidence rate between pyrosequencing and Sanger squencing was 100%. The coincidence rate between the result of pyrosequencing and of genechip method was 91.7%. The reproducibility of this assay was 97. 8%. It indicates the pre-C/BCP pyrosequencing is a high-accurate method with, good-reproducibility and high-reliability. And multi-site detection can be achieved by pyrosequencing one time. A rare mutation T1758C was also detected. Conclusion Pyrosequencing for pre-C/BCP mutations assay is high-throughout method for simultaneous detection of multi-site mutation.

Objective: To investigate the influencing factors of sulfated modification of Bupleurum chinense polysaccharides (BCP),and to elucidate the possible mechanism of improving the antioxidant ability of sulfated BCP (S-BCP).Methods:BCP was sulfated by chlorosulfonic acid-pyridine method.The degree of substitution (DS)of S-BCP was observed by adjusting the volume ratios of chlorosulfonic acid to pyridine (1:2,1:4,and 1:8).The structures of BCP and S-BCP were analyzed by infrared (IR)spectroscopy,the morphology of BCP and S-BCP were observed under scanning electron microscopy (SEM).The antioxidant model was established by using 1, 1-diphenyl-2-picrylhydrazyl (DPPH)free radical scavenging.The experiment was divided into positive control group,BCP group and S-BCP group,and the scavenging rates of DPPH free radical in various groups were compared. Results:When the volume ratio of chlorosulfonic acid to pyridine was 1 : 4,the reaction time was 2 h and the reaction temperature was 60 ℃,the maximum sulfur content percentage of S-BCP was 18.62% and the DS was the highest (DS = 2.32 ).Compared with BCP group, the scavenging rate of DPPH free radical of S-BCP was significantly increased (P <0.05).Conclusion:The volume ratio of chlorosulfonic acid to pyridine can affect the DS of S-BCP.The sulfated modification can increase the anti-oxidant capacity of BCP by changing its physic-chemical characters and spatial conformation.