Objective To investigate the effects of liraglutide on the gut microbiota of db/db diabetic mice and the predictive value of the microbial structure for the hypoglycemic efficacy.Methods The db/db mice were randomly divided into control group and liraglutide group(0.4 μg/g).Fasting blood glucose levels were measured in the mice,and fecal samples were collected to determine the structure of the gut microbiota.Results Compared with the control group,the liraglutide group exhibi-ted a significant increase in the average number of operational taxonomic unit(OTU)(P＜0.01).The number of observed species,Chao1 index and ACE index were all significantly higher in the liraglutide group than those in the control group(P＜0.05).Additionally,the liraglutide group showed a signifi-cant increase in the relative abundance of Firmicutes and a significant decrease in the abundance of Actinobacteria compared with the control group(P＜0.01).The percentage decrease in blood glucose levels in db/db mice was positively correlated with the abundance of Pseudomonadaceae and negatively correlated with the abundances of Clostridiaceae and Peptostreptococcaceae.Conclusion Liraglutide treatment can modulate the structure of the gut microbiota,increasing the number of OTU and diversity,particularly enhancing the abundance of beneficial bacteria such as Clostridium,Lachnospira and Oscillospira.The gut microbiota structure in mice serves as a predictive factor for the hypoglycemic efficacy of liraglutide,with diabetic mice exhibiting a higher abundance of Pseudomonas being more likely to benefit from liraglutide-induced hypoglycemic therapy.

Objective:To explore the technical advantages of MR cholangiopancreatography (MRCP) with single breath holding high parallel acquisition factor 3-D variable flip angle fast spin echo (3D-SPACE) sequence.Methods:From November 2018 to March 2019, 75 patients who underwent MRCP examination in our hospital were prospectively enrolled, with single breath holding high parallel acquisition factor 3D-SPACE sequence and free breathing navigation gated 3D-SPACE sequence. Three experienced radiologists scored the overall image quality, artifacts, CBD visibility, left and right hepatic ducts, right anterior and posterior branches, second and third branches, main pancreatic duct and gallbladder duct with four scales. Paired t test was used for statistical analysis. Results:The scanning time of single breath holding method (18 s) was significantly shorter than that of free breathing diaphragm navigation method［264（226，313）s］, and the difference between the two methods was statistically significant ( Z=-7.520， P<0.001). The SNR, CR and CNR (8.31±4.23, 0.92±0.30, 11.46±5.77) of single breath holding method were lower than those of free breathing diaphragm navigation method (11.23±5.70, 0.93±0.38, 15.06±7.37), and the differences between the two methods were also statistically significant ( t=4.378, 3.429, 4.063, P<0.05). The overall image quality, artifact, the CBD, left and right hepatic duct, right anterior and posterior branchs, the second and third branches, main pancreatic duct and cystic duct of single breath holding method were higher than those of free breathing diaphragm navigation method, and the differences between the two methods were statistically significant ( P<0.001). Conclusions:Compared with the free breathing diaphragm navigation gated 3D-SPACE MRCP imaging method, the single breath holding high parallel acquisition factor 3D-SPACE MRCP imaging method has less artifacts and examination time, but higher visibility to pancreaticobiliary tree and work efficiency, which is worthy of further promotion.