Research on the in vitro differentiation of embryonic stem cell(ES) is one of the hotspots in the study about developmental biology and cell transplantation therapy. But ethical issues and immune rejection remained to be the reasons which obstruct the progress. Recently, scientists have successfully obtained a kind of phripotent stem cell named induced phripotent stem cells (iPS). Since iPS posses similar properties with ES and can be autologously derived from patients themselves, it is a potential substitute of ES beth in the basic research and clinical application and the above mentioned problems can be avoided. However, iPS must differentiate to specific cells before being used in the clinical therapeutic research. The present article provides a concise summary of current progress on the differentiation ofiPS cell as well as some existing problems.

Objective To observe the suppression of special shRNA producing plasmid to hepatitis B virus(HBV) S gene and C gene on HBV replication and expression in HepG2.2.15 cells.Methods pSilenceCircle-U6 including pol Ⅲ promoter was used to construct HBV special shRNA producing plasmid as SC-S and SC-C.The experimental groups included SC-S group,SC-C group,unrelated control SC-N group and blank control group.With different dosages and at different time,shRNA producing plasmid was transfected into HepG2.2.15 cells.HBeAg and HBsAg in the culture media was detected by ELISA assay and HBV DNA in the culture media was measured by dot blotting assay. Results The recombinant shRNA producing plasmid with target sequence was constructed successfully.The inhibitory rates of HBeAg and HBsAg expressions by SC-S were much higher than those by SC-C.The inhibitory effects of HBeAg and HBsAg expressions were increased when the dose of SC-S was greater.The inhibitory effects of HBeAg and HBsAg expressions by SC-S were significant on the 3rd day after transfection and the inhibitory effect was the strongest on the 6th day.The inhibitory rate was still higher on the 9th day after transfection.Dot blotting assay showed the inhibitory effect of HBV replication by SC-S was greater than that by SC-C.Conclusion The shRNA producing plasmid with HBV S gene and C gene can be highly effective to inhibit the replication and expression of HBV.

Objective To investigate the value of single photon emission computed tomography (CT) imaging and transmis‐sion CT imaging (microSPECT‐CT ) bremsstrahlung imaging for the solid tumor mesenchymal implantaion of 32 P‐chromic phos‐phate‐paclitaxel‐poly‐L‐lactic acid (32 P‐CP‐PSP‐PLLA) sustained release seeds and to investigate the 32 P in vivo biodistribution and degradation sustained release churacteristics .Methods The animal model of prostate cancer subcutaneously transplanted tumor was established .32 P‐CP‐PSP‐PLLA sustained‐release seeds were intratumorally implanted by the mediation of microSPECT‐CT brems‐strahlung imaging and the 32 P distribution in bearing tumor mouse was verified by the imaging and biological distrubtion tests .The ultrastructural changes of 32 P seeds were observed by the scanning electron microscope .Results The MicroSPECT/CT brems‐strahlung imaging could effectively guide the intratumoral implantation operation of the 32 P sustained‐release seeds with clear visu‐alization .Partial sustained‐release 32 P was remained in the tumor tissues with little distribution in important organs of spleen and liver ,which was proved by the biodistribution results .The particle surface and inside micropores and tunnels formation ,their pro‐gressive increase ,fusion and connection were found by the electronic microscope after the 32 P sustained‐release seeds intratumoral implantation .Conclusion The MicroSPECT/CT bremsstrahlung imaging can effectively monitor the 32 P sustained‐release seeds and their in vivo biodistribution and lays a foundation for the sustained‐release seeds prostatic targeted implantation .

BACKGROUND: Reports of culture condition of olfactory ensheathing cells (OECs) vary. And some methods have bad reproducibility, not appropriate for actual application.OBJECTIVE: To observe the effect of differential attachment, chemicals in combination with trypsin digestion to purify rat OECs in vitro and to compare the effect with differential attachment or chemicals alone.DESIGN, TIME AND SETTING: In vitro controlled observation of cytology was performed at the Laboratory of Department of Human Anatomy & Histology and Embryology, Fujian Medical University from June 2007 to June 2008.MATERIALS: A total of 8 SD rats, 2 days old, were provided by the Laboratory Animal Center of Fujian Medical University.METHODS: The OECs were dissociated from the postnatal rat olfactory bulbs under sterile condition, and seeded in poly-L-lysine-coated culture flask at a density of 4.0×10~8 /L for primary culture. The cells were divided into 4 groups: control group (not purified); chemicals group (5 μmol/L arabinose); differential attachement group (Nash differential attachement); combination group (Nash differential attachement to eliminate most of the fibroblasts, followed by arabinose; when the cells were confluent at 6 days, the cells were digested with 1.25 g/L trypsin for 1 minute until the processes were shrank, cells became round, with some cells floating).MAIN OUTCOME MEASURES: Morphological changes of the cultured OECs and NGFRp75 immunocytochemistry were observed.RESULTS: The OECs displayed a very characteristic morphological appearance. Most of OECs were bipolar or tripolar with long and slim processes. In the unpurified control group the rapidly proliferating fibroblasts were in the majority (60%) after 7 days in culture, and confluent at day 14. The OECs occupied the most in the other groups, and their appearance remained unchanged.The surviving bipolar or tripolar OECs were positive for NGFRp75. The purifity by chemicals and differential attacehment methods was low (75%), while the combination group was high (85%).CONCLUSION: The method of purifing OECs through a combination of differential attacehment, chemicals and trypsinization is effective.

Objective To study the relationship among the slow vertex response (SVR) ,tone burst ABR threshold and pure tone thresholds in young people with normal hearing ,and to discuss the values of SVR and tb -ABR assessing hearing thresholds .Methods A total of 30 normal-hearing young people aged 20 to 24 were indud-ed in this study .The thresholds of SVR ,tb -ABR and threshold of PTA were tested at each verbal frequency (0 .5 ,1 ,2 ,4 kHz) .The differences and the relationship among SVR with PTA ,tb-ABR ,and PTA were statistical-ly studied .Results The differences between SVR and tb -ABR and PTA at various frequencies were statistically significant (P<0 .05) .The minimum difference between SVR and PTA was (3 .59 ± 7 .32) dB at 0 .5 kHz .The differences of 1 ,2 ,and 4 kHz were 6 .92 ± 5 .07 ,8 .33 ± 6 .71 ,and 9 .83 ± 9 .41 dB ,respectively .The minimum differences between tb -ABR and PTA was 14 .58 ± 7 .24 dB at 4 kHz ,and the differences of 0 .5 ,1 ,and 2 kHz were 29 .42 ± 6 .83 ,23 .25 ± 7 .47 ,and 16 .50 ± 6 .43 dB ,respectively .SVR and PTA had a good correlation at 1 and 2 kHz (r=0 .51 ,P<0 .01 and r=0 .44 ,P<0 .05 ,respectively) .tb-ABR and PTA had a good correlation at 4 kHz (r=0 .53 ,P<0 .01) .Conclusion In normal hearing young population ,SVR and tb-ABR can estimate PTA well , and the former is closer to PTA threshold .

Objective To explore the efficacy and safety of the treatment of Xuezhikang and fluvastatin in elderly angina patients with mildly abnormal liver function .Methods 84 cases of ALT in 40-80u/L very elderly patients with coronary heart disease were randomly selected and divided into the two groups , the Xuezhikang group received Xuezhikang (0.6g,bid,orally),the fluvastatin group received fluvastatin (40mg,1time/night,oral),the total course was 12weeks,the TC,TG,LDL-C,HDL -C were measured before and after treatment ,liver function was measured once 2 -4times.If ALT was 3 times higher than before , Xuezhikang was instead of statins , if ALT was 5 times higher than before ,both of the two drags were withdrawaled .Results The TC,LDL,TG,HDL-C and ALT of the two groups were no significant difference before treatment (P >0.05),the TC,LDL,TG were decreased after treatment in the both group .There was no case of increased of ALT to three times in Xuezhikang group ,however ,ALT of 6 patients were increased more than three times in fluvastatin group ,four weeks after exchange of Xuezhikang ,the ALT were not continued to rise .Conclusion Both the two medicine can significantly lowered the cholesterol in very elderly patients with angina ,but the Xuezhikang were more safety in the patient with mild increased of liver function .

BACKGROUND:The glass ionomer cement has good biological stability and can sustain the release of fluoride, which has been used as dental repair materials. But because of its low mechanical strength, the glass ionomer cement is confined to the front teeth and other parts with smal er force.
OBJECTIVE:To analyze the compressive strength, microleakage and other physical performances of Fuji IX glass ionomer cement after the addition of 8%modified nano-hydroxyapatite.
METHODS:(1) Universal testing machine was applied to detect the compressive strength of Fuji IX glass ionomer cement, Fuji IX glass ionomer cement added with 8%modified nano-hydroxyapatite, and super glass ionomer to fil the stainless steel cylinder. (2) Fuji IX glass ionomer cement, Fuji IX glass ionomer cement with 8%modified nano-hydroxyapatite and super glass ionomer were used to fil the tooth cavity;then, the microleakage was detected. (3) Fuji IX glass ionomer cement, Fuji IX glass ionomer cement added with 8%modified nano-hydroxyapatite, and super glass ionomer were used to fil stainless steel rectangular specimens. Then, universal material testing machine was applied to detect the bending strength value.
RESULTS AND CONCLUSION:The compressive strength, microleakage, and bending strength of specimens fil ed with Fuji IX glass ionomer cement the addition of 8%modified nano-hydroxyapatite were better than the other two groups, and Fuji IX glass ionomer cement was superior to the super glass ionomer in the compressive strength, microleakage and bending strength of fil ed specimens. It is shown that Fuji IX glass ionomer cement after addition of 8%improved nano-hydroxyapatite can improve the compressive strength and microleakage.

Objective To discuss the etiology and treatment of extrahepatic biliary stenosis due to iatrogenic bile duct injuries. Methods A total of 12 cases of extrahepatic biliary stenosis after iatrogenic bile duct injuries(including 5 cases of open cholecystectomy and 7 cases of laparoscopic cholecystectomy) from January 1998 to January 2005 in this hospital was reviewed.After the establishment of a percutaneous transhepatic access,choledochoscopic stone removal,balloon dilatation,and drainage stent placement were performed for treating biliary stenosis.Results A F_(20) Gruntzig balloon catheter was employed for bile duct dilatation.The plastic drainage stent at 6~8 mm in diameter was successfully placed after 2 times of dilatation in 8 cases and after 3 times of dilatation in 4 cases,for 6~12 months of indwelling.Follow-up observations in the 12 cases for 2~3 years (mean,2.6 years) found no abdominal pain,fever,or jaundice.B-ultrasonography and MRCP findings showed no biliary stenosis and recurrent stones.Conclusions Choledochoscopic stone removal,balloon dilatation,and drainage stent placement are minimally invasive,safe,and effective in the treatment of extrahepatic biliary stenosis.

Objective To investigate methods and effects of percutaneous choledochoscopy via cholangio-jejunal anastomotic stoma in the treatment of recurrent intrahepatic biliary duct stones. Methods Eight cases of recurrent intrahepatic biliary duct stones after a Roux-en-Y cholangiojejunostomy from January 2000 to February 2005 were treated with percutaneous choledochoscopy. An enterostomy was made at the afferent jejunal loop. Then a choledochoscope was introduced into the intrahepatic biliary ducts by way of the cholangio-jejunal anastomotic stoma for stone removal and intrahepatic duct or anastomotic stoma dilatation. Results The intrahepatic stones were thoroughly removed in all the 8 cases. The biliary duct stenosis in 4 cases and the anastomotic stoma stenosis in 2 cases were relieved. Follow-up checkups in the 8 cases for 1~3 years revealed no recurrence of intrahepatic stones or stenosis. Conclusions Percutaneous choledochoscopy via cholangio-jejunal anastomotic stoma is minimally-invasive, safe, feasible, and effective in the treatment of recurrent intrahepatic biliary duct stones.

Objective To evaluate the clinical effect and safety of homemade biodegradable drug eluting stents(Excel stents)in patients with coronary heart disease.Methods Two hundred and twelve patients who received Excel stents implantation during February,2006 to March 2007 were included in the study.Procedural success rate and complications during hospitalization were monitored and all the patients were followed up clinically up to 8-21 months after discharge.Results The procedural success rate was 99.1%(210/212).A total of 420 Excel stents were implanted while direct stenting was applied in 125 patients(29.8%).Sudden cardiac death happened in 1 patient during hospitalization.Two hundred and six patients finished their clinical follow up and among them,6 patients had recurrant angina.Fifty patients received CAG examination 6-9 months after PCI and 2 patients reached the criteria of restenosis(stenosis ≥50%)and required revascularization.Conclusion Homemade biodegradable drug eluting stents(Excel stents)are safe and effective for PCI in coronary heart disease patients.