Engineered 3D-Printed Polyvinyl Alcohol Scaffolds Incorporating ß-Tricalcium Phosphate and Icariin Induce Bone Regeneration in Rat Skull Defect Model.

The skull defects are challenging to self-heal, and autologous bone graft repair has numerous drawbacks. The scaffolds for the rapid and effective repair of skull defects have become an important research topic. In this study, polyvinyl alcohol (PVA)/ß-tricalcium phosphate(ß-TCP) composite scaffolds containing icariin (ICA) were prepared through direct-ink three-dimensional (3D) printing technology. ß-TCP in the composite scaffold had osteoconductive capability, and the ICA molecule had osteoinductive capacity. The ß-TCP and ICA components in the composite scaffold can enhance the capability to repair skull defects. We show that ICA exhibited a slow-release behaviour within 80 days. This behaviour helped the scaffold to continuously stimulate the formation of new bone. The results of in vitro cell compatibility experiments showed that the addition of ICA molecules contributed to the adhesion and proliferation of MC-3T3-E1 cells. The level of alkaline phosphatase secretion demonstrated that the slow release of ICA can promote the osteogenic differentiation of MC-3T3-E1 cells. The introduction of ICA molecules accelerated the in situ bone regeneration in in vivo. It is concluded that the 3D-printed PVA scaffold with ß-TCP and ICA has a wide range of potential applications in the field of skull defect treatment.

Effect of supplemental simethicone for bowel preparation on adenoma detection during colonoscopy: A meta-analysis of randomized controlled trials.

BACKGROUND AND AIM: Although several randomized controlled trials (RCTs) have reported that supplemental simethicone (SIM) can improve bowel preparation based on polyethylene glycol, there is no consensus as to whether SIM can ultimately increase the adenoma detection rate (ADR) during colonoscopy. A meta-analysis was performed to assess the effect of SIM on ADR during colonoscopy. METHODS: Databases including PubMed, EMBASE, and the Cochrane Library were searched to find relevant RCTs. RCTs evaluating the effect of pre-procedure SIM on the ADR during colonoscopy were finally included, and fixed effect models were applied. RESULTS: Six trials involving 1855 patients were finally included. The present meta-analysis suggested that the ADR during colonoscopy was significantly increased by supplemental SIM (27.9% vs 23.3%, P = 0.02), with a relative risk of 1.20 (95% confidence interval 1.03-1.39). Subgroup analysis suggested that supplemental SIM may be more useful to improve ADR during colonoscopy in endoscopic centers with low baseline ADR. CONCLUSIONS: Supplemental SIM for bowel preparation based on polyethylene glycol is useful to improve the ADR during colonoscopy.