BACKGROUND: Human embryonic stem cells (hESCs) are pluripotent cells which may differentiate into tissues of all three germ layers. Such research as the feeder-free growth of hESCs is few in China. Fibroblast growth factor (FGF) is a major factor to maintain the undifferentiated state of hESCs.OBJECTIVE: To evaluate the ability of FGF at different concentrations in maintaining the undifferentiated state and pluripotency of hESC lines in the long-term culture.METHODS: Two cell lines of hES-8 and hES-18 were cultured with mouse embryonic fibroblast condition medium for 3 passages and then transferred into mouse embryonic fibroblast condition medium containing different concentrations of FGF: 100, 160, 250 μg/L for 8 passages. The hESCs were removed from the petri dish, cell clusters were digested with collagenase IV and gathered. Cell differentiation and pluripotency were observed. The eighth generation of the hESCs were collected and incubated into severe combined immunodeficiency mice, so as to observe teratoma formation. Morphologies of the cells were evaluated. Alkaline phosphatase staining, surface labeling immunocytochemical analysis and RT-PCR assay method were utilized to determine the OCT-4 expression and tumorigenesis in vivo.RESULTS AND CONCLUSION: Cultured in mouse embryonic fibroblast condition medium containing 160 and 250 μg/L FGF, two cell lines of hESC could maintain undifferentiated state: Clones were round with a high ratio of nucleus to cytoplasm. Large areas in the center of clones were undifferentiated cells, while surrounding the clones were differentiated cells; Strong positive expression for alkaline phosphatase staining was observed; Two cell lines showed high levels of OCT-4 transcription factor protein; The surface markers SSEA-4, TRA-1-60, TRA-1-81 were all positive on both two lines; The hESC clusters could form embryoid body in vivo 10 days later; 3 germ layers of teratomas were also obtained after implanted into severe combined immunodeficiency mice. Mouse embryonic fibroblast condition medium containing 100 μg/L FGF was not sufficient to maintain the long-term proliferation of hESCs, and most of the cells differentiated and died after 4 passages. Alone with concentration 160 μg/LbFGF or more could maintain two hESC lines undifferentiated stably in vitro, has no influence on the differentiation and totipotency of two cell lines.

Based on a review of literature and the current reform of public hospital corporate governance,such corporate governance is divided intocombined regulation and operation,anddivided regulation and operationmodels.Then the principal-agent theory was called into play to analyze the main problems and causes of the existing models.From the perspectives of government supervision and assessment,professionalization of hospital directors,market competition mechanism,thoughts were made on how to improve such corporate governance.

Objective To explore the effects of inflammatory mediator blocker AG490 on neurological deficits,apoptosis and expression of caspase-3 following cerebral ischemia-reperfusion(I/R) in rats.Methods The male SD rats were randomly divided into the groups sham-operation,I/R,saline and AG490;and the focal cerebral I/R models were made by middle cerebral artery thread embolism method.AG490(1 mg/kg) was intraperitoneal injection in AG490 group immediate and 12 h after ischemia-reperfusion respectively.The neurological deficits score was evaluated in 24 h after I/R in each group.The number of apoptosis in cerebral tissue was examined by d-utp nick end labeling staining(TUNEL).The expression of P-JAK2,P-STAT3,caspase-3 were detected by Western Blot.Results Compared with the groups I/R and saline,the neurological deficits score in AG490 group was significantly decreased(all P

Constant infusion, exponentially declining infusion and program infusion of theophlline were administered to rabbits byadopting the rabbit population pharmacokinetic parameters in this laboratory, and the plasma concentrations of the drug was measured by ul- traviolet spectrophotometry. The results showed that the plasma drug concentrations following exponentially declining infusion and program infusion attained the desired steady-state level at only 30 min, though the T1/2?= 6. 08h, The median absolute value of performance error in pro-gram infusion and exponentially declining infusion was 7. 8% and 14% respectively.

Phospholipase A_2 (PLA_2) inhibitor quinacrine was used to explore protective effect on multiple organ dysfunction (MOD) caused by intestinal ischemia-reperfusion (I/R) in rats. Gut I/R caused the increase of gut PLA_2 activity and induced endotoxemia and bacteriemia. Pretreatment with intravenous quinacrine 10mg?kg~(-1) attenuated bacteria and endotoxin translocation,markedly lowered the levels of thromboxane A_2 and prostacyclin I_2 in blood,and provided protection from the development of vital organs dysfunction. As a result,the survival rate in pretreatment group increased by 25%. The results demonstrate that gut I/R promotes gut barrier failure,then contributes to the development of MOD by allowing bacteria or endotoxin reaching the circulation. PLA_2 and PLA_2-dependent lipid mediators play an important role in the development of gut I/R injury and MOD. Intravenous quinacrine has protection against MOD resulting from gut I/R.

Objective: We investigated experimentally the changes of intestinal immunity following shock and resuscitation after trauma. Method:The experimental model was made in rats, which underwent laparotomy, then bleeding and reinfusing through the right fetmoral artery. Result: The concentration of IgA following shock and resuscitation were significantly higher than that before shock.. The concentration of IgA 24 h following resuscitation was the lowest, and was significantly lower than that at the end of shock.. The endotoxin in portal vein following shock and resuscitation were higher than that before shock.. The endotoxin level 24 h following resuscitation was the highest, and markedly higher than that at the end of shock. Conclusion: The traumatic shock and resuscitation are capable of causing intestinal immunosuppression and endotoxemia.

To compare the clinical effect and side-effect of intravenous PCA(PCIA) with epidural PCA (PCEA). Method: One hundred and eighty postoperative patients, who were randomly divided into three groups: group PCIA, group PCEA and control, were observed for 3 days after operation. Result: Overall patients in two PCA groups were satisfied with the postoperative analgesia. The incidence of urinary retention in group PCIA were significantly lower than that in group PCEA (P0.05). 10% in group PCIA were in medium sedation whereas no eases in group PCEA were in sedation. At 6th hour after operation,serum cortisol level of control patients was much higher than that of PCA patients. Conclusion=Both PCIA and PCEA have excellent analgesia and reduce stress response after operation. PClA has lower incidence of urinary retention and is performed easily,but inhibits gastrointestinal motility much more and has higher sedative incidence compared with PCEA.

Objective: To investigate the effects of pentoxifylline (PTX) on oxygen free radicals induced myocardial injury. Method: An in vivo myocardial impairment model was developed in SD rat with exogenous oxygen free radicals. The changes cardiac performance and serum malonylaldehyde (MDA), lactic acid, cretine phosphokinase (CK) levels were tested before and at different interval after I. V. administration of oxygen free redieal. Result: Myocardial performance after oxygen free radicals administration was significantly depressed compared to the baseline values (P

0.05 ),the O- 2 production increased significantly (P

Objective To evaluate the efficacy of PTX on the global cerebral ischemia reperfusion injuryMethods The global cerebral ischemia of gerbils was induced by clamping bilateral carotid arteries for 30 min , then declamping with the reperfusion lasting 90 min At the beginning of ischemia , PTX 25mg?kg -1 or 50mg?kg -1 was administered intravenously by mini infusion pump In another group , PTX 25mg?kg -1 was infused at the beginning of reperfusion In sham operated and control groups the same volume of 0 9% NaCl were infused 0 2% Even's blue 1ml?100g -1 was injected intraperitoneally At the end of experiment , The gerbils were decapitated to be preserved at -70℃ for measurement of water contents of whole hemispheres , cerebral superoxide dimutase (SOD) activity, malonyldialdehyde (MDA) content and Even's blue content Results As compared with those in control group, at the beginning of ischemia or reperfusion ,the administration with PTX 25mg?kg -1 significantly reduced the cerebral water content (P