1.Effects of early postburn escharectomy on the permeability of cadiac and pulmonary blood vessels in rats
Zhiqing LI ; Zongcheng YANG ; Jiahan WAN ; Yuesheng HUANG
Journal of Third Military Medical University 2001;23(4):393-394
Objective To evaluate the prophylactic-therapeutic role of escharectomy during early postburn stage on internal organ dysfunction. Methods A total of 72 Wistar rats were randomized into 3 groups: burn without escharectomy group (A group), burn with escharectomy during early postburn stage (B group) and normal control. Vascular permeability were measured with 99Tc-labelled albumin. Furthermore, the effect of burn sera on permeability of monolayer of vascular endothelial cell (EC) was observed. Results Vascular permeability in group B was significantly lower than in group A. When exposed to burn sera, EC monolayer permeability in group B is decreased when compared with group A. Conclusion Escharectomy during early postburn stage could restore endothelial permeability
2.Platelet membrane biomimetic nanoparticles for tumor photothermal therapy:a preliminary in vitro study
Gang YANG ; Jianming WU ; Dongkai XU ; Qingze FAN ; Jiahan ZHOU ; Shengli WAN
Academic Journal of Naval Medical University 2024;45(8):999-1004
Objective To prepare indocyanine green(ICG)-loaded platelet membrane biomimetic liposome(ICG-PLP)for tumor photothermal therapy,and to preliminarily evaluate its in vitro characteristics.Methods ICG-PLP was prepared by an ultrasound method,and its particle size and zeta potential were determined using a laser particle size analyzer.The encapsulation efficiency of ICG-PLP was detected by ultraviolet spectrophotometry.The photothermal properties of ICG-PLP were investigated under 808 nm near-infrared ray irradiation(2 W/cm2),and the retention of platelet membrane proteins was observed by sodium dodecylsulfate-polyacrylamide gel electrophoresis.The uptake of ICG-PLP by mouse macrophage RAW264.7,human non-small cell lung cancer cell A549,mouse melanoma cell B16-F10,and mouse breast cancer cell 4T1 was observed by a laser confocal microscope.Furthermore,the phototoxicity of ICG-PLP was detected by methyl thiazolyl tetrazolium assay,and the safety of ICG-PLP was preliminarily evaluated according to hemolysis rate and cytocompatibility.Besides,the in vivo retention time of ICG,ICG-loaded liposome and ICG-PLP in healthy SD rats was observed after tail vein injection.Results ICG-PLP was successfully prepared and its encapsulation efficiency,particle size,zeta potential,and the polydispersity index were(97.68±0.01)%,(109.77±0.76)nm,(-21.23±0.84)mV,and 0.22±0.01,respectively.ICG-PLP well retained the proteins on platelet membrane and showed good photothermal properties.Platelet membrane enhanced the uptake of biomimetic nanoparticles by tumor cells A549,B16-F10,and 4T1,and reduced the phagocytosis of biomimetic nanoparticles by macrophages.ICG-PLP exhibited a favorable photothermal therapy effect and could kill tumor cells.Additionally,ICG-PLP displayed a good safety.After intravenous administration,ICG-PLP prolonged the in vivo retention time of ICG in healthy SD rats.Conclusion ICG-PLP has been successfully constructed.It has a great potential in targeted drug delivery and tumor photothermal therapy.