Transcatheter aortic heart valves(TAHVs) have been widely used for aortic valve replacements, with less trauma and lower clinical risk compared with traditional surgical heart valve replacements. In the present study,...Transcatheter aortic heart valves(TAHVs) have been widely used for aortic valve replacements, with less trauma and lower clinical risk compared with traditional surgical heart valve replacements. In the present study, composites of poly(ethylene glycol) diacrylate(PEGDA) hydrogels and anisotropic highshrinkage polyethylene terephthalate/polyamide6(PET-PA6) fabric(PEGDA/PET-PA6) were fabricated as artificial heart valve leaflets. Dynamic mechanical analyses(DMA) indicated that PEGDA/PET-PA6 composites possessed anisotropic mechanical properties(i.e., storage moduli ~23.30 ± 1.36 MPa parallel to the aligned fabric fibers and ~9.68 ± 0.90 MPa perpendicular to the aligned fibers at 1 Hz) that were comparable to aortic valve leaflets. The PEGDA/PET-PA6 composites with smooth surfaces were highly hydrophilic(contact angle ~41.6°± 3.8°) and had low-fouling properties without platelet adhesion,suggesting a low risk of thrombogenicity when they interacted with blood. Furthermore, transcatheter aortic heart valves were fabricated using nitinol self-expanding frames and PEGDA/PET-PA6 composites as artificial leaflets, which presented excellent hemodynamic performance with a large orifice area(1.75cm2) and low regurgitation(3.41%), thus meeting the requirements of ISO 5840-3 standard. Therefore,PEGDA/PET-PA6 composites had suitable mechanical properties, good biocompatibility, and low-fouling properties, indicating that they might be used for TAHVs in the future.展开更多
The optical interference intensity ROll technique, which enables measurements of filmthickness of magnitude below half of the wavelength of the incident light, is widely used in thestudy of thin film lubrication (TFL)...The optical interference intensity ROll technique, which enables measurements of filmthickness of magnitude below half of the wavelength of the incident light, is widely used in thestudy of thin film lubrication (TFL). However, the absorbing characteristics of the metallic compo-nents which are for generating suitable amount of reflectance to facilitate optimum inference im-ages has never been taken into consideration. This paper presents a theoretical analysis of theabsorbing characteristics. Results indicate that without acknowledging the absorbing effects, sig-nificant errors in film thickness measurements can be induced.展开更多
基金supportedby the National Natural Science Foundation of China(Nos.31670981 and 31300788)the Hundred-Talent Program from Chinese Academy of Sciences
文摘Transcatheter aortic heart valves(TAHVs) have been widely used for aortic valve replacements, with less trauma and lower clinical risk compared with traditional surgical heart valve replacements. In the present study, composites of poly(ethylene glycol) diacrylate(PEGDA) hydrogels and anisotropic highshrinkage polyethylene terephthalate/polyamide6(PET-PA6) fabric(PEGDA/PET-PA6) were fabricated as artificial heart valve leaflets. Dynamic mechanical analyses(DMA) indicated that PEGDA/PET-PA6 composites possessed anisotropic mechanical properties(i.e., storage moduli ~23.30 ± 1.36 MPa parallel to the aligned fabric fibers and ~9.68 ± 0.90 MPa perpendicular to the aligned fibers at 1 Hz) that were comparable to aortic valve leaflets. The PEGDA/PET-PA6 composites with smooth surfaces were highly hydrophilic(contact angle ~41.6°± 3.8°) and had low-fouling properties without platelet adhesion,suggesting a low risk of thrombogenicity when they interacted with blood. Furthermore, transcatheter aortic heart valves were fabricated using nitinol self-expanding frames and PEGDA/PET-PA6 composites as artificial leaflets, which presented excellent hemodynamic performance with a large orifice area(1.75cm2) and low regurgitation(3.41%), thus meeting the requirements of ISO 5840-3 standard. Therefore,PEGDA/PET-PA6 composites had suitable mechanical properties, good biocompatibility, and low-fouling properties, indicating that they might be used for TAHVs in the future.
文摘The optical interference intensity ROll technique, which enables measurements of filmthickness of magnitude below half of the wavelength of the incident light, is widely used in thestudy of thin film lubrication (TFL). However, the absorbing characteristics of the metallic compo-nents which are for generating suitable amount of reflectance to facilitate optimum inference im-ages has never been taken into consideration. This paper presents a theoretical analysis of theabsorbing characteristics. Results indicate that without acknowledging the absorbing effects, sig-nificant errors in film thickness measurements can be induced.
