Preliminary Study on Effect of Biomimetic Nanomaterials of Homologous Cancer Cell Membrane on Pancreatic Cancer

Author:Chu Yun Mian

Supervisor:wang cheng feng


Degree Year:2019





Background Effect on traditional treatments of pancreatic cancer is bleak.In all the new methods of treatments,photothermal therapy(PTT)and photodynamic therapy(PDT)have good prospects.Carbon-based mesoporous silica nanoparticles(CSNs),which combine the principle of PDT and PTT,can enhance the effect of killing cancer cells.After the cancer cells’ membrane is coated on the CSNs(MCSNs),CSNs will gain homologous targeting and will be more easily taken up by cancer cells,which further improving the treatment effect.Method The human pancreatic cancer cell line,Bxpc-3 and the rat colorectal cancer cell line,CT26 were cultured and the cell membrane of Bxpc-3 was extracted and coated on the surface of CSNs with diameter of 100 nm and then MCSNs was prepared.The structure and characterization of MCSNs,CSNs and cell membrane were observed by transmission electron microscope and nanometer granularity potentiometer.The intensity of endocytosis of MCSNs and CSNs by Bxpc-3 and CT26 at different time points were observed by laser confocal scanning microscopy and the effect on Bxpc-3 by MCSNs and CSNs after near-infrared laser irradiation was compared.Result The homologous cell membrane biomimetic photothermal nanomaterials can significantly improve the endocytosis of Bxpc-3 and the most significant difference happens at 10th min and 8th hour.With the increase of the concentration of CSNs,the effect of killing pancreatic cancer cells is better.MCSNs can significantly specific improve the killing effect on pancreatic cancer cells compared to CSNs.Conclusion CSNs have good effect on killing pancreatic cancer cells.MCSNs can further enhance the killing effect.Objective To explore the effect of operation periods on early complications after pancreaticoduodenectomy(PD)and provide a new way of decreasing early postoperative complications.Methods The clinical data of 311 patients who underwent PD in our department were collected.According to the time of operation,patients were divided into the morning group and the afternoon group.The complications between the two groups were compared.Results In the morning group,117 patients had complications.In the afternoon group,23 patients had complications.Total complication morbidity between the two groups was statistically different(48.1%vs 33.8%,P=0.036<0.05).The incidence of grade A delayed gastric emptying in the morning group was significantly higher than that in the afternoon group(18.1%vs 5.9%,P=0.014<0.05).But the incidence of the remaining complications between the two groups was no statictically different.Conclusions The morbidity of grade A delayed gastric emptying in the afternoon is lower than that in the morning group and it is expected to provide a new entry point for reducing early complications after PD.Objective Comparing with other pancreatic operations,central pancreatectomy(CP)has less effect on body.Surgeons should be proficient in this surgical method.In this study,we want to explore the learning curve of CP and provide an excellent reference for surgeons to get the point of this operation.Methods Clinical data of 73 patients who underwent CP in a same operation team from January 2006 to January 2018 were collected and retrospectively analyzed by the Moving Average Method(MAM)and the Cumulative Sum Method(CUSUM).Data was also analyzed by Statistical Package for Social Science(SPSS)software.Results From the MAM and CUSUM curves,it indicated that the learning process of CP could be divided into two stages.At the first stage(N=1-11),the average operation time was 331 minutes and the average intraoperative hemorrhage was 368 ml.In the second stage(N=12-73),the average operation time was 221 minutes and the average intraoperative hemorrhage was 164 ml.The difference was statistically significant(P=0.000,P<0.05).There was no significant difference between the two stages of patients in terms of other aspects(P>0.05).Conclusion CP can be mastered after 11 cases.In the first 11 operations,surgeons should get familiar with the operation process,respond actively to emergencies and accumulate experience to gain this suigical technique fast.