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Objective To investigate the effects of shock and vibration on the automated peritoneal dialysis(APD)module in the ICU compartment of the sanitary train during operation.Methods ANSYS-based modal analysis and harmonious response analysis of the APD module on the sanitary train were carried out according to IEC 61373:2010"Railway applications—Rolling stock equipment—Shock and vibration tests"so as to calibrate the strength,stiffness and stability of the whole module structure,and to optimize the weak links.The power spectral density was selected as the excitation according to IEC 61373:2010,and the rationality of the module design was verified by random vibration test and equipment impact test.Results Modal analysis results showed that the natural frequency of the simplified model of the optimized APD fixed support was improved overall,and the second to sixth order frequencies were 156.45,166.35,268.85 and 285.45 Hz,respectively.Harmonic response analysis indicated that the damping platform of the APD module had a low amplitude not more than 2.2 mm.The results of impact and random vibration experiments proved that there were no obvious structural deformation and cracking phenomenon and abnormal mechanical properties and appearance found in the APD module.Conclusion The APD module is well-designed and can be embedded into the ICU compartment of the sanitary train.[Chinese Medical Equipment Journal,2023,44(9):38-41]
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Background Stromal cell-derived factor-1_?(SDF-1_?)has been demonstrated to be essential for stern cell mobilization/homing.Recent evidence indicates that SDF-1_? has been expressed in injured carotid arter- ies.Besides,high SDF-1_? plasma levels are clinically associated with stable coronary artery disease.Objective To investigate whether SDF 1 involves in mobilization of endothelial progenitor cells(EPC)and reendothelialization after vascular injury.Methods SDF-1_? was detected by RT-PCR and Western blot in carotid arteries of mice at different time points after wire-induced injury.SDF-1_? determination in peripheral blood samples and BM was per- formed by SDF-1_? enzyme-linked immunosorbent assay(ELISA)kit.EPC in peripheral blood collected at different time points after vascular injury were quantified by flow cytornetry.In subgroup,blocking SDF-1 rnonoclonal anti- body was injected,peripheral blood EPC were quantified after vascular injury and reendothelialization of injured ar- teries was determined 14 days later.Results Expression of SDF-1_? was evident at day 1,and peaked at day 3 after arterial injury.A rise in plasmatic concentration of SDF-1_? and a significant reduction of SDF-1_? in bone marrow concentration was noticed at all time points following injury.The amount of circulating EPC was increased shortly after induction of vascular injury and persisted up to 7 days(P