Theoretical Model Study on Morphology of Lipid Droplet on Inner Vascular Wall / 医用生物力学

Objective To establish the theoretical model for morphology of lipid droplets adhering to inner vascular wall, so as to provide the theoretical model for the study and analysis of the overall morphology of lipid droplets on inner vascular wall of patients with fat embolism. MethodsThe model of the droplet with variable radius on inner wall of the cylindrical tube was established to describe morphology of lipid droplets on inner vascular wall, and accuracy of the theoretical model was verified by Surface Evolver (SE) software simulation results. According to the theoretical model, the influencing patterns of lipid droplet volume and contact angle on dimensionless adhesion area Sb0 and blockage ratio κ of lipid droplets in blood vessels were analyzed. Results The theoretical model could predict contour parameters of adhesion morphology for lipid droplets on inner vascular wall, including the height and arc radius of lipid droplet at azimuth angle of 0 and π/2. The relative errors between contour parameters obtained from the theoretical model and corresponding parameters obtained from the SE simulation were smaller than 10%. For lipid droplets with the same dimensionless volume V0, Sb0 of inner vascular wall decreased with contact angle increasing, and blockage ratio κ increased with contact angle increasing. At the same contact angle, the smaller V0 , the smaller Sb0 and κ would be. Conclusions The established theoretical model with variable radius can well describe morphological characteristics of lipid droplets on inner vascular wall. The influening pattern of volume, contact angle and other parameters on height, adhesion area and cross-sectional area of lipid droplets can be accurately and quickly obtained through the theoretical model, indicating that the larger the contact angle of lipid droplets or the smaller the dimensionless volume, the lower the probability of embolism. The research findings provide theoretical support for the analysis on related diseases.

A primary study of endoscopic closure of acute gastric perforation using twin grasper combined with endoloops in a porcine survival model / 中华消化内镜杂志

Objective To evaluate the feasibility and efficacy of twin grasper combined with endoloops on closing acute stomach perforation.Methods Two experimental porcines of stomach perforation underwent endoscopic closure by twin grasper combined with endoloops.Survival conditions and closure of perforating were observed.Results Mild infection and abdominal adhesions were observed in one week after operation.The nylon rope fell off and an ulcer-like lesion was presented in the closed position.The methylene blue leak test was negative.Histologic examination revealed chronic inflammatory cells infiltration,granulation,fibroplasias,and regenerative mucous membrane crawling toward the center of perforation.Conclusion The technique of twin grasper combined with nylon ropes in closing the acute stomach perforation is feasible and effective.