ABSTRACT
It is well known that Tokyo University Hospital (TUH) is one of the most famous medical centers around the world in Japan. Among several departments in TUH, the Department of Hepatobiliary-Pancreatic Surgery and Artificial Organ and Transplantation Division are representative predominant divisions, which have high-quality diagnostic and treatment service systems being at the leading position in the world. The authors visit the Department of Hepatobiliary-Pancreatic Surgery and Artificial Organ and Transplantation Division in 2022. When studying and working in TUH, the authors make a multi-angle comparisons of the development status and technical levels of hepatobiliary and pancreatic surgery among TUH, western countries and China. It aims to share and exchange with fellow surgeons at home and abroad, and bring benefits or enlightenment to the professional advancement of them.
ABSTRACT
This paper is aimed to observe the hepatocyte growth factor (HGF) loading and delivery ability of polylactic acid and oxygen carboxymethylated chitosan copolyer nanoparticles (PLA-O-CMC NPs). We prepared PLA-O-CMC NPs loaded with HGF by ultrasound in combination with magnetic stirring method. The NPs were characterized by transmission electron microscopy, embedding ratio; drug loading and drug delivery behaviors were observed by ELISA. The characteristics of PLA-O-CMC NPs loaded with HGF showed that the mean size was 139. 82 nm, polydispersity was 0.108, maximal HGF-embedding ratio was 76. 32%. The cumulative HGF release gradually increased in the first 24 hours in vitro, with sharp increasing in the first 7 hours, and moderate and steady increasing in the following 17 hours. The HGF had a burst release in the first 24 hours, and in this process the released HGF took up 36.7% of the whole release. From the second day,the HGF release decreased obviously, while it kept on releasing steadily (45-55 ng/d) for quite long time up to 30 days. The experiment proved that PLA-O-CMC NPs is a favourable carrier of HGF. PLA-O-CMC NPs loaded with HGF could rapidly release HGF in vitro. The released HGF reached the effective drug concentration and maintained the certain effective drug concentration for a long time.