BACKGROUND:Oligo(poly(ethylene glycol)fumarate) (OPF) hydrogel is a kind of biomaterial with good biocompatibility, injectability, and biodegradability. It is known that there are differences in the characteristics of hydrogels with different molecular weights. Under osteogenic induction, bone marrow mesenchymal stem cels encapsulated in the suitable molecular weight hydrogel have better proliferation and differentiation. Therefore, the use of OPF hydrogel provides new options for bone tissue-engineered scaffold.
OBJECTIVE:To investigate the effect of OPF hydrogel with different molecular weights on the proliferation and differentiation of encapsulated rat bone marrow mesenchymal stem celsin vitro.
METHODS: Four kinds of OPF hydrogels with molecular weights of 1 000, 3 000, 10 000 and 35 000 were developed by OPF crosslinking with a redox radical initiation system. Hydrogel sweling and degradation properties were detected. Afterwards, bone marrow mesenchymal stem cels encapsulated in different hydrogels were cultured in osteogenic medium for 1-3 weeks. The effects of hydrogels on morphplogy of bone marrow mesenchymal stem cels and osteogenic differentiation were detectedvia histological staining (hematoxylin-eosin staining and alizarin red staining) and immunofluorescence staining.
RESULTS AND CONCLUSION: With the increase of molecular weight of hydrogels, the gelation time was shortened, the sweling ratio significantly increased, and the hydrogel degradation rate was proportional to the molecular weight. In addition, the number of mineralized nodules formed in 3 000 and 10 000 molecular weight hydrogels was more than that in the other hydrogels, indicating that hydrogels with appropriate sweling and degradation properties are beneficial to cel proliferation and differentiation. In conclusion, OPF hydrogels have good biocompatibility and hydrogels with 3 000 and 10 000 molecular weight play active regulatory roles in osteogenic differentiation of mesenchymal stem cels.

Correlated with such hepatic-systemic factors as cirrhosis, inflammation and immunity, portal vein thrombosis (PVT) is common in perioperative period of liver transplantation (LT) recipients.It affects negatively surgical procedures and outcomes due to its insidious onset and atypical clinical symptoms.With continuous improvements of LT techniques and refining of medical imaging, researchers have gained further insights into the pathophysiological processes, screening, diagnoses, evaluations, classifications and perioperative managements of PVT.This review focused upon perioperative managements of LT recipients with PVT to enhance the clinical problem-solving capability and long-term patient survival.