Objective:o prepare Danshensu liposomes and investigate drug release characteristics in vitro. Methods: Danshensu liposomes were prepared by a reverse-phase evaporation method. The encapsulation efficiency was used as the index, an orthogonal test was adopted to investigate the effect of concentration of soybean lecithin, ratio of lipid-Danshensu and pH value of solution on the preparation procedure of Danshensu liposomes. The particle size of the liposomes was also investigated by a transmission electron micro-scope ( TEM) . The concentration of Danshensu was determined by HPLC, and the difference of release characteristics in Danshensu li-posomes and Danshensu solution was measured by a dialysis method. Results:The optimum preparation technology was as follows:the concentration of soybean lecithin was 40 mg·ml-1 ,the ratio of drug-lipid was 1: 10,and the pH value of solution was 6. 6. The mor-phology of the prepared liposomes showed spheric structure with uniform diameter, and the average particle size was ( 174 ± 36 ) nm and the encapsulation efficiency was 38. 9%. The linear range of Danshensu was 2. 0-20. 0 mg·L-1(r=0. 9984). The drug release of liposomes in vitro was slower than that of free Danshensu solution in 24 h. Conclusion:Danshensu liposomes with fine morphology have sustained release property.

In recent years, driven by high-throughput sequencing technology, it has been found that changes in the proportion of specific microbiota are related to the occurrence and development of pancreatic cancer, including oral microbes, gastrointestinal flora, and pancreatic flora. Porphyromonas has a positive correlation with pancreatic cancer risk, which may provide new biomarkers for the diagnosis of pancreatic cancer. In addition, the microbiota is closely related to various treatments for pancreatic cancer. When the intestinal flora is imbalanced, it will affect the effect of chemotherapy. Bacteria in pancreatic cancer can induce immune tolerance. Complications with bacterial infection can lead to postoperative complications increase.

目的：粪 肠 球 菌 脂 磷 壁 酸 （ lipoteichoic acid， LTA） 对 胰 腺 导 管 腺 癌 （ pancreatic ductal adenocarcinoma， PDA） BxPC3 细胞增殖、侵袭和迁移的影响及其可能的机制。方法：用 0、5、10、50 μg/ml 的 LTA 分别处理 BxPC-3 细胞，以 0 μg/ml 组作为空白对照组，其余各组作为实验组，采用 CCK-8 法检测 LTA 对细胞 BxPC-3 增殖的影响；用 50 μg/ml LTA 处理 BxPC-3 细胞 48 h，采用划痕实验和 Transwell 小室实验分别检测其对 BxPC-3 细胞侵袭和迁移的影响，WB 法检测对 BxPC3 细 胞中 TLR2、P38、p-P38、NF-κB 和 p-NF-κB 蛋白表达的影响。结果：LTA 抑制 BxPC3 细胞的增殖，且抑制作用随时间和浓度的 增加而增强，与 0 μg/ml 组相比，在 LTA 50 μg/ml 干预 48 h 后，BxPC-3 细胞增殖抑制效果最为显著（P<0.01），故后续实验组细胞均采用 50 μg/ml LTA 处理 48 h。与 0 μg/ml 组相比，50 μg/ml 组发生侵袭的 BxPC-3 细胞数和迁移率均显著降低（均 P<0.01），细胞中 TLR2、p-P38、p-NF-κB 蛋白水平均显著升高（均 P<0.01）。结论：粪肠球菌 LTA 可抑制 PDA 细胞 BxPC-3 的增殖、侵袭和迁移， 其机制可能与 LTA 激活 TLR2 进而促进 P38 及 NF-κB 磷酸化有关。