Stem cells are characterized by the ability to renew themselves and differentiate into a di-verse range of specialized cell types.Bmi1 gene has been determined to play critical roles in the self-renewal of stem cells.Many of the tumor originated in stem cells.Enhanced self-renewal capability in stem/progenitor cells changes its biological characteristic and drives tumor initiation

Objective To investigate the efficacy of heart value replacement on elderly patients and summarize the experience of surgical treatment.Methods The clinical data and follow-up status of 76 elderly patients were analyzed retrospectively in our hospital from January 2008 to December 2011.The operative method,general effect,postoperative death,postoperative complications,survival rate and life quality followed-up were analyzed.Results No intraoperative death appeared and there were 4 early operative deaths with a mortality rate of 5.3％.There were 31 cases occurred postoperative complication with a complication rate of 40.8％ which including respiratory insufficiency,lung infection,arrhythmia,incision infection,pleural effusion,low cardiac output syndrome and renal insufficiency.The follow-up time was 18-52 months and the mean follow-up time was (24.7± 3.6)months.There were 5 cases lost of follow up and the follow-up rate was 93.4％.There were 6 patients died after a month postoperative with a mortality rate of 7.9％.The heart function of the survivors achieved differed degree improvements and the result at the end of follow-up were grade Ⅰ-Ⅱ 47 cases,grade Ⅲ 13 cases and grade Ⅳ 6 cases.Conclusions To correctly determine the surgery indications,do all the preoperative preparation,intraoperative rigorous operating with a good myocardial protection and to strengthen the postoperative care will be help to reduce the mortality and complications of the elderly patients with heart value replacement.

[Objective]To evaluate the effect of massive bioactive bone substitute in repairing large animals bone defect and to know its degrading rate.[Method]The massive Polylevolactic acid?collage calcium phosphate(PLLA?cTCP) carrieres by rapid forming technology was making,and then compounding rhBMP-2 and carrieres in a ratio of 3mg rhBMP-2 to one carrier was compounded to prepare the massive bioactive bone substitutes for dogs bone defect.Then the massive bone substitutes were implanted into 2.0cm dogss radius defects in the experiment group,and the massive carriers were implanted into in the control group.The repairing effect was evaluated by radiography,histology and biomechanics,and the degrading rate of the substitues was calculated in an image analysis apparatus.[Result]Radiographically,in the experiment group,the defects were connected by callus in all dogs in 12 weeks postoperatively;in 24 weeks,the callus rebuilt well.But in the control group,there was no callus formed in 24 weeks postoperatively,and the defects were not repaired.Histologically,in 12 weeks postoperatively,the outer layer of the callus in the experiment groups was lamellar bone and the center were trabecular bone,myeloid tissue and partial degrading carrier;in 24 weeks,the lamellar bone was more compact,trabecular bone decreased,myeloid tissue increased,and the carrier degraded more.In the control group,in 12 weeks postoperatively,the fibrous tissue wrapped and infiltrated into carrier,at the same time,part of the carrier degraded;in 24 weeks,the carrier was divided up by fibrous tissue and degraded more.The degrading rate of the carder in 12 weeks in the experiment group was 43.2%,in the control group was 35.7%,in 24 weeks 58.4% and 45.4%.Biomechanics,in 24 weeks after postoperation,the radius strength in the experiment group was superior to that in the normal bone.[Conclusion]The massive bioactive bone substitutes have satisfactory repairing effect on the radius bone defects of the large animal,but its degrading rate needs improving.

Objective To investigate the biological effects of low intensity of pulsed ultrasound (LIPUS) on human periosteal cells and marrow stromal cells in vitro. Methods LIPUS of 30 mW/cm2 was used to stimulate the cultured human periosteal cells and marrow stromal cells for 5 min, 10 and 20 min per day, respectively, followed by the examination of cell proliferation and differentiation potential. Results Thymidine incorporation and total protein assay indicated that LIPUS had no significant effect on DNA and protein synthesis of the periosteal and marrow stromal cells, suggesting that LIPUS did not promote proliferation of these cells. However, ALP activity and osteocalcin secretion of the human periosteal cells were dramatically increased. Conclusion The results suggested that low intensity pulsed ultrasound stimulated periosteal cell proliferation and differentiation toward osteogenic lineage, this might contribute to the curing effect of low intensity pulsed ultrasound for fracture.

Objective: To investigate the knowledge and behaviors related to hepatitis B prevention and control among carriers of hepatitis B surface antigen (HBsAg), so as to provide the basis for conducting health education and interventions for HBsAg carriers. Methods: Based on the seroepidemiological survey of hepatitis B among individuals aged 1 to 69 years in Shaanxi Province, HBsAg carriers were selected as the study subjects. Basic information, knowledge and behaviors about hepatitis B prevention and control were collected through questionnaire surveys. The awareness of hepatitis B prevention and control knowledge and related behaviors among HBsAg carriers were analyzed. Results: A total of 107 HBsAg carriers were enrolled, including 52 males (48.60%) and 55 females (51.40%), and had a median age of 47.04 (interquartile range, 19.78) years. The awareness of hepatitis B prevention and control knowledge ranged from 56.07% to 87.85% among HBsAg carriers, with the highest awareness for "hepatitis B vaccination can effectively prevent hepatitis B "(87.85%), and the lowest awareness for "sharing meals with HBsAg carriers or hepatitis B patients will not lead to infection" (56.07%) and "hepatitis B can be treated with antiviral drugs" (61.68%). The proportions of those who did not seek medical consultation, undergo regular check-ups, or receive treatment were relatively high, at 65.42%, 72.90% and 77.57%, respectively. Conclusions The awareness of hepatitis B transmission routes and treatment-related knowledge among HBsAg carriers is relatively low, and their medical-seeking behaviors are relatively passive. There is a need to enhance the dissemination of hepatitis B prevention and control knowledge, improve medical-seeking behaviors, and reduce the risk of hepatitis B virus transmission.

Objective To observe the effect of vascular endothelial cell growth factor (VEGF)on apoptosis and matrix metabolism of rat intervertebral.disc cells cultured in vitro. Methods Culture system of rat intervertebral disc cells was established to culture the monolayer intervertebral disc cells in vitro.The well-grown intervertebral disc cells of the second generation were chosen and anti-Fas antibody was applied to induce their apoptosis.Then,VEGF at different concentrations ( 10,100,1 000 μg/L)were used to affect their apoptosis and metabolism.The apoptosis of the cells stained with Propidium Iodide (PI) was detected by using flow cytometry.The levels of hydroxyproline and proteoglycan in the culture medium were detected by using chloramines T method and DMB chromometry method,respectively.Results ( 1 ) The apoptotic ratio of the intervertebral disc cells affected by different concentrations of VEGF (10,100,1 000 μg/L) was (87.62 ±11.06)％,(53.30 ±9.23)％ and (16.75 ±4.21)％ respectively,with significant differences in comparison with the control group (P ＜ 0.01 ).(2)The contents of hydroxyproline [ (6.71 ±0.33) μg/L,(9.12 ±0.41 ) μg/L,( 11.58 ±0.12) μg/L] and proteoglycan [ (23.21 ± 2.87) μg/L,( 32.45 ± 5.23 ) μg/L,(37.18 ± 3.22) μg/] in the culture medium raised with the increase of VEGF concentration ( 10,100,1 000 μg/L),with statistical differences compared with those of the control group (P ＜0.01 ).The contents of hydroxyproline and proteoglycan were positively correlated with the concentration of VEGF (ra=0.972,P＜0.01;rb =0.907,P＜0.01). Conclusion VEGF can inhibit the apoptosis of the rat intervertebral disc cells cultured in vitro and promote collagen and proteoglycan synthesis of the cell matrix.

Objective To investigate the effects of over-expression of homo sapiens eukaryotic translation elongation factor 1 alpha 2 (EEF1A2) on in vitro invasion and lung metastasis of human pancreatic cancer SW1990 cells.Methods Letivirus-mediated delivery of EEF1A2 was used to enhance the expression of EEF1A2 gene in human pancreatic cancer SW1990 cells,the SW1990 cells stably over-expressing EEF1A2 protein (SW1990/EEF1A2 cells) were obtained,and the parent SW1990 cells and SW1990/GFP cells were used as the control,and the expressions of EEF1 A2 mRNA and protein were determined by Real-time PCR and Western blotting.The invasion ability of cells was determined by Transwell assay.The lung metastasis model was established by injection of SW1990 cells into the tail vein.Whole lung tissues were harvested,and visible nodules on tung surface were counted macroscopically 8 weeks later.Results The EEF1 A2 mRNA expression of SW1990/EEF1A2 was 3.252 ± 0.344,which was significantly higher than those in SW1990/GFP cells (1.000 ±0.060) and SW1990 cells (0.944 ±0.041,t =2.255,2.305,P＜0.01) ; the EEF1A2 protein expression was 0.833 ± 0.050,which was significantly higher than those in SW1990/GFP cells (0.247 ± 0.035) and SW1990 cells (0.273± 0.041,t=0.572,0.559,P＜0.01).The ability of invasion of SW1990/EEF1A2 cells was (60 ±4) cells,which was sigmificantly higher than (33 ±4) cells in SW1990/GFP group and (26 ± 3) cells in SW1990 group (t =31.33,34.78,P ＜ 0.01).Furthernore,SW1990/EEF1 A2 cells had a much higher incidence of lung metastasis in nude mice than SW1990/GFP cells and SW1990 cells in vivo (100％ vs.20％,20％,P ＜ 0.05).Conclusions EEF1 A2 over-expression can obviously increase the in vitro invasion and lung metastasis of pancreatic cancer SW1990 cells.

Composition of the polysaccharide from Bupleurum scorzonerifolium Willd. was studiedby high resolution capillary gas chromatography after hydrolysis and followed by acetylation and esterifica-tion of the hydrolysate. The results showed that it is composed of arabinose, ribose, D-xylose, D-man-nose, D-glucose and D-galactose, with a molar ratio of 0. 106 : 2. 652 : 4. 070: 0. 519 : 0. 930 : 2. 518.

Due to their biological and physiological importance, flavonoids received considerable attention in the literature. This review discusses the widely used analytical method i.e. capillary electrophoresis (CE) including the chiral flavonoids separation and the hyphenation of CE and MS. Techniques used for enhancement of sensitivity such as stacking, sweeping, isotachophoresis etc. were also discussed.

Objective To explore the risk factors for hepatitis B virus (HBV) intrauterine infection to provide a scientific ev idence for itsprevention.Methods Three hundred and twelve pregnant women of HBsAg positive screened from April 2013 to May 2015 served as the research subjects and were followed up until 6 months after birth.The infantile mothers of HBsAg and/or HBV DNA positive were selected as the intrauterine infection case group,while other mothers served as the control group.The Logistic regression analysis was adopted to analyze the risk factors for intrauterine HBV infection.The questionnaire survey method was used to collect the basic data and time-resolved immunofluorescence assay was used to detect HBsAg.PCR was adopted to measure level of HBV DNA and automatic biochemistry analyzer was used to measure the hepatic functional parameters including ALT,AST,triglyceride and cholesterol.Results The single factor analysis results indicated that HBeAg,HBV DNA,contamination of amniotic fluid and sexual behavior during pregnancy were related to HBV intrauterine infection(P＜0.05).The multiple variate Logistic regression results showed that positive HBeAg(OR=2.76,95 ％ CI=1.19-7.94),positive HBV DNA(OR=9.62,95 ％ CI=2.58-35.33),and sexual behaviors during pregnancy (OR =1.53,95 ％ CI =1.07-6.40) were the risk factors for intrauterine HBV infection.Conclusion Pregnant women with positive HBeAg,positive HBV DNA and sexual behavior during pregnancy may be the high risk factors for neonatal intrauterine HBV infection.