ObjectiveTo investigate the growth characteristics of pancreatic cancer cells in the twodimensional culture system (monolayer) and threedimensional culture system (type Ⅰ collagen and extracellular matrix gel). MethodsThree pancreatic cancer cell lines (SW1990, PCT, and ASPC1) were cultured in monolayer, type Ⅰ collagen, and extracellular matrix gel, respectively. The growth patterns were observed, growth curves were detected by CCK8 test, and the cell cycle distributions were analyzed by propidium iodide staining. Results In the twodimensional culture system, cells grew in monolayer. In the type Ⅰ collagen and the ECM gel threedimensional culture system, cells formed multicellular spheroids (MCS), of which the growth rates were slower than those of the cells in monolayer. The proportions of S phase of SW1990, PCT, and ASPC1 cells in twodimensional culture system were significantly more than those in the type Ⅰ collagen on 4 d and 8 d 〔(29.6±3.0)% vs. (18.2±5.1)%, (33.6±2.1)% vs. (14.5±3.2)%, (33.1±1.8)% vs. (24.7±2.6)%; Plt;0.05〕, while the difference of proportion of three cell lines in G2/M phase was not different between twodimensional culture system and type Ⅰ collagen (Pgt;0.05). The proportions of G0/G1 phase of SW1990 and PCT cells cultured in the type Ⅰ collagen on 4 d and 8 d and ASPC1 cells cultured in the type Ⅰ collagen on 4 d were significant more than those cultured in twodimensional culture system (Plt;0.05). The proportions of S phase of ASPC1 cells and SW1990 cells cultured in the type Ⅰ collagen on 4 d were significant more than those cultured in the type Ⅰ collagen on 8 d (Plt;0.05). ConclusionsThe characteristics of pancreatic cancer cells in twodimensional and threedimensional culture systems are different. MCS culture system can better mimic the in vivo growth environment of cells in tumors.
ObjectiveTo study the prevention and treatment of restenosis after the stent placement in the latest progress. MethodsThere were four methods including drug-eluting stents, intracavitary illuminate, drug therapy, and mesenchymal stem cells, which prevented or treatment restenosis after stent placement. ResultsAll the four methods could reduce the postoperative restenosis rate after interventional treatment. Many experimental study of prevention and treatment of restenosis had obvious effect, but clinical curative effect was not very satisfactory, because of a series of problems such as safety, animal models, experiment method, and so on. ConclusionThe multiple factors and links caused restenosis should be considered fully, and interrupting the links or factors as far as possible could control the occurrence or development effectively.
Objective To evaluate the efficacy of the light cured flowable composite resin and the light cured pit and fissure sealant in the prevention of dental caries in children. Methods EMbase, CBM, The Cochrane Library, PubMed, Web of Science, CNKI, WanFang Data and VIP databases were searched from inception to January 1st, 2017 for randomized controlled trials (RCTs) or quasi-RCTs about the application of the light cured flowable composite resin and the light cured pit and fissure sealants. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then, the RevMan 5.3 software was applied to conduct meta-analysis. Results A total of 13 studies were included. The results of meta-analysis showed that the complete retention rate of the light cured flowable composite resin group was higher than that of the light cured pit and fissure sealant group (6 months: RR=1.03, 95%CI 1.00 to 1.06, P=0.03; 12 months: RR=1.09, 95%CI 1.04 to 1.13, P=0.000 3; 24 months: RR=1.22, 95%CI 1.13 to 1.31, P<0.000 01). The incidence of caries of the light cured flowable composite resin group was lower than that of the light cured pit and fissure sealant group (12 months: Peto OR=0.30, 95%CI 0.16 to 0.56,P=0.000 2; 24 months: Peto OR=0.44, 95%CI 0.31 to 0.63, P<0.000 01). Conclusion The light cured flowable composite resin is superior to the light cured pit and fissure sealant in the complete retention and caries prevention. The above conclusions are needed to be verified by more high-quality clinical studies because of the limitation of the quality and follow-up time of studies.
【摘要】 目的 比较胫骨平台骨折术后辅助与不辅助持续被动运动（continuous passive motion，CPM）的临床疗效。 方法 对2008年6月-2009年6月86例行手术治疗的闭合性、无合并损伤的胫骨平台骨折患者进行回顾性分析。根据是否辅助CPM分为CPM组27例和非CPM组（对照组）59例。对两组患者的伤口愈合情况，膝关节屈曲、伸直角度，以及膝关节功能恢复情况进行比较。 结果 两组伤口甲级愈合率差异无统计学意义（P=0.566）。在术后2周和6周，CPM组患者的膝关节屈曲角度明显大于对照组（Plt;0.001），但在术后3个月和12个月，两组的差异无统计学意义（P=0.219，P=0.512）。在术后2、6周，3、12个月，CPM组和对照组患者的膝关节伸直角度差异无统计学意义。在术后12个月的Rasmussen膝关节功能评分方面，CPM组和对照组的差异无统计学意义。 结论 胫骨平台骨折术后辅助CPM能早期提升膝关节屈曲角度，但并不能提高远期的膝关节活动度和最终的膝关节功能。【Abstract】 Objective To compare the therapeutic effect of continuous passive motion (CPM) treatment after tibial plateau fractures operation. Methods From June 2008 to June 2009, 86 patients were treated due to closed tibial plateau fractures without combined injuries. The patients were treated with (27 patients, CPM group) and without (59 patients, control group) CPM. The wound healing rates, range of motion and the knee function were compared between the two groups. Results There was no significant difference between the two groups in wound healing rates (P=0.566). Two and six weeks after the operation, there were significant differences between the two groups in flexion degree (Plt;0.001); three and 12 months after the operation, there were no significant differences between the two groups (P=0.219, P=0.512). At the 2nd and 6th week, 3rd and 12th month postoperatively, there were no significant differences between the groups in extension degree. Twelve months after the operation, there were no significant differences between the groups in functional recovery of the knee. Conclusion CPM in the post-operative treatment of tibial plateau fractures is effective increasing knee flexion in the early stage, but is not effective increasing range of motion or knee function in a long term.
Having searched The Cochrane Library (Issue 4, 2005), we found: fluoride can reduce the occurrence and severity of white spot lesions; removal of premature contacts of the primary teeth can prevent posterior crossbite; expanding the top teeth can decrease the risk of a posterior crossbite; CSF may help retaining teeth; clear overlay retainer may settle teeth quicker than Hawley retainer; adhesives for fixed orthodontic brackets is still in dispute.
Objective To investigate the effects of long time different negative pressures on osteogenic diffe-rentiation of rabbit bone mesenchymal stem cells (BMSCs). Methods The rabbit BMSCs were isolated and cultured by density gradient centrifugation. Flow cytometry was used to analyze expression of surface markers. The third passage cells cultured under condition of osteogenic induction and under different negative pressure of 0 mm Hg (control group), 75 mm Hg (low negative pressure group), and 150 mm Hg (high negative pressure group) (1 mm Hg=0.133 kPa), and the negative pressure time was 30 min/h. Cell growth was observed under phase contrast microscopy, and the growth curve was drawn; alkaline phosphatase (ALP) activity was detected by ELISA after induced for 3, 7, and 14 days. The mRNA and protein expressions of collagen type I (COL-I) and osteocalcin (OC) in BMSCs were analyzed by real-time fluorescence quantitative PCR and Western blot. Results The cultured cells were identified as BMSCs by flow cytometry. The third passage BMSCs exhibited typical long shuttle and irregular shape. Cell proliferation was inhibited with the increase of negative pressure. After induced for 4 days, the cell number of high negative pressure group was significantly less than that in control group and low negative pressure group (P<0.05), but there was no significant difference between the low negative pressure group and the control group (P>0.05); at 5-7 days, the cell number showed significant difference between 3 groups (P<0.05). The greater the negative pressure was, the greater the inhibition of cell proliferation was. There was no significant difference in ALP activity between groups at 3 days after induction (P>0.05); the ALP activity showed significant difference (P<0.05) between the high negative pressure group and the control group at 7 days after induction; and significant difference was found in the ALP activity between 3 groups at 14 days after induction (P<0.05). The greater the negative pressure was, the higher the ALP activity was. Real-time fluorescence quantitative PCR and Western blot detection showed that the mRNA and protein expressions of COL-I and OC protein were significantly higher in low negative pressure group and high negative pressure group than control group (P<0.05), and in the high negative pressure group than the low negative pressure group (P<0.05). Conclusion With the increase of the negative pressure, the osteogenic differentiation ability of BMSCs increases gradually, but the cell proliferation is inhibited.