Objective To investigate the protective effect of Klotho on renal ischema-reperfusion injury (IRI).Methods Plasmid expression vector of secreting type Klotho (pV5-sKlotho) was injected through the tail vein 24 h before operation.The renal ischemia-reperfusion model was established and the experiment was divided into 6 groups:sham group of young mice,sham group of aged mice,control group of young mice,control group of aged mice group,Klotho transfected group of young mice and Klotho transfected group of aged mice.The serum creatinine (Cr) and blood urea nitrogen (BUN) levels were determined at 1st,3rd,7th,and 14th after reperfusion.The mRNA expression of Klotho and P53 in the renal tissue,concentration of the malondialdehyde (MDA),superoxide dismutase (SOD) and pathological changes in the renal tissue were examined.Results As compared with young mice group,the Cr and BUN levels were significantly increased after reperfusion (P<0.05),the expression of Klotho mRNA was significantly decreased (P<0.05) and the expression of P53 mRNA was significantly increased (P<0.05),the MDA level in the renal kidney tissue was significantly increased and SOD level was significantly decreased (P<0.05) in aged mice.Vacuolar degeneration and necrosis in tubules were major pathological changes 24 h after operation in aged mice,and at 14th day after IRI renal tubular atrophy,fibrosis and inflammatory cell infiltration were seen in aged mice.After transfection with pV5-sKlotho,as compared with control group of aged mice,the kidney function was significantly improved in Klotho transfected group of aged mice (P<0.05),and the up-regulated expression of Klotho and down-regulated expression of P53 were detected in Klotho transfected group of aged mice (P<0.05),also the MDA level in the renal tissue was obviously reduced and SOD level was obviously increased (P<0.05).Vacuolar degeneration and necrosis in tubules at 24th h after IRI and tubular atrophy,fibrosis and inflammatory cell infiltration at 14th day after IRI were significantly improved in Klotho transfected group of aged mice.Conclusion Transfection with Klotho can protect the acute kidney injury and chronic kidney disease induced by IRI in aged mice.

Objective: To detect the hemodynamic mechanism of the novel endovascular stent on complicated abdominal aortic aneurysms by Computational Fluid Dynamics(CFD) firstly, and then compare the effect of the novel endovascular stent and the streamliner multilayer flow modulator(SMFM) stent. Methods: All medical images were obtained by computed tomography. A semiautomatic segmentation protocol within Mimics(v17.0; Materialise, Leuven, Belgium) was used to extract the threedimensional aortic aneurysms. The stents was generated numerically and fitted along the aortic aneurysms. The lumen volume represented the fluid domain that was discretised in smaller volumes, which defined a mesh within the ICEM software(Ansys ICEM CFD v15.0). Hemodynamic analysis was performed with software Fluent 16.0. Results: Both kinds of stents can change the pattern of flow distribution. Compared with SMFM, the novel endovascular stent can significantly reduce the flow velocity in aneurysms, the shear force and the pressure on the aneurysms wall.What’s more, the flow velocity of the branch artery was accelerated by the novel endovascular stent. Conclusion The novel endovascular stent can significantly reduce the flow velocity in aneurysms, the shear force and the pressure on the aneurysms wall, and acceleratethe the flow velocity of the branch artery.