Serum urate is associated with an increased risk of inflammatory bowel disease: A bidirectional Mendelian randomization study

BACKGROUND Previous studies have indicated bidirectional associations between urate levels and inflammatory bowel disease(IBD),including ulcerative colitis(UC)and Crohn’s disease(CD).However,it remains unclear whether the observations are causal because of confounding factors.AIM To investigate the causal associations between urate levels and IBD using bidirec-tional Mendelian randomization(MR).METHODS Independent genetic variants for urate levels and IBD were selected as instru-mental variables from published genome-wide association studies(GWASs).Summary statistics for instrument-outcome associations were retrieved from three separate databases for IBD(the UK Biobank,the FinnGen database and a large GWAS meta-analysis)and one for urate levels(a large GWAS meta-analysis).MR analyses included the inverse-variance-weighted method,weighted-median estimator,MR-Egger and sensitivity analyses(MR-PRESSO).A meta-analysis was also conducted to merge the data from separate outcome databases using a fixed-effects model.RESULTS Genetically higher serum urate levels were strongly associated with an increased risk of UC[odds ratio(OR):1.95,95%confidence interval(CI):1.86-2.05]after outlier correction,and the ORs(95%CIs)for IBD and CD were 0.94(95%CI:0.86-1.03)and 0.91(95%CI:0.80-1.04),respectively.Animal studies have confirmed the positive association between urate levels and UC.Moreover,genetically predicted IBD was inversely related to urate levels(OR:0.97,95%CI:0.94-0.99).However,no association was observed between genetically influenced UC or CD and urate levels.CONCLUSION Urate levels might be risk factors for UC,whereas genetically predicted IBD was inversely associated with urate levels.These findings provide essential new insight for treating and preventing IBD.

Patient-specific three-dimensional printed heart models benefit preoperative planning for complex congenital heart disease

Background Preoperative planning for children with congenital heart diseases remains crucial and challenging.This study aimed to investigate the roles of three-dimensional printed patient-specific heart models in the presurgical planning for complex congenital heart disease.Methods From May 2017 to January 2018,15 children diagnosed with complex congenital heart disease were included in this study.Heart models were printed based on computed tomography (CT) imaging reconstruction by a 3D printer with photosensitive resin using the stereolithography apparatus technology.Surgery options were first evaluated by a sophisticated cardiac surgery group using CT images only,and then surgical plans were also set up based on heart models.Results Fifteen 3D printed heart models were successfully generated.According to the decisions based on CT,13 cases were consistent with real options,while the other 2 were not.According to 3D printed heart models,all the 15 cases were consistent with real options.Unfortunately,one child diagnosed with complete transposition of great arteries combined with interruption of aortic arch (type A) died 5 days after operation due to postoperative low cardiac output syndrome.The cardiologists,especially the younger ones,considered that these 3D printed heart models with tangible,physical and comprehensive illustrations were beneficial for preoperative planning of complex congenital heart diseases.Conclusion 3D printed heart models are beneficial and promising in preoperative planning for complex congenital heart diseases,and are able to help conform or even improve the surgery options.