<strong>Background:</strong> Placenta extract is used as an alternative medicine especially in Asian countries as it is a rich reservoir of diverse bioactive molecules. The effects of placenta extract on s...<strong>Background:</strong> Placenta extract is used as an alternative medicine especially in Asian countries as it is a rich reservoir of diverse bioactive molecules. The effects of placenta extract on skin conditions have been previously reported, however, the mechanism underlying for reduced wrinkle formation remains unclear. <strong>Objective:</strong> The primary objective of this study was to determine whether the continuous application of porcine placenta extract (PPE) alleviates wrinkle formation in humans and explore the underlying mechanism. <strong>Methods:</strong> Wrinkle formation, skin hydration, and skin elasticity were measured in 15 volunteers at weeks 0 and 6 after continuous application of a gel containing PPE. The production of type I collagen and hyaluronic acid from fibroblasts and keratinocytes, respectively, were measured using ELISA. Expression levels of ceramide synthase 3 (CERS3), filaggrin (FLG), transglutaminase 1 (TGM1), and kallikrein-7 (KLK7) were evaluated by quantitative real-time PCR. <strong>Results:</strong> The wrinkle index was significantly reduced to 72.1% after a 6-week of applying the PPE gel, along with a significant increase in skin hydration to 126.5%. Type I collagen production from fibroblasts was enhanced slightly but significantly following treatment with PPE. PPE accelerated the expression of CERS3 (1.85-fold), FLG (1.35-fold), TGM1 (1.76-fold), and KLK7 (1.62-fold). <strong>Conclusion:</strong> Treatment with PPE alleviates wrinkle formation and simultaneously enhances skin hydration, which is induced via the accelerated expression of moisturizing-related proteins. These findings suggest that PPE is effective for combating dryness-induced wrinkle formation.展开更多
The planar force model of prepreg,initially established based on the principle of minimum potential energy and the Rayleigh-Ritz method,was improved by considering the difference between the tensile and compressive mo...The planar force model of prepreg,initially established based on the principle of minimum potential energy and the Rayleigh-Ritz method,was improved by considering the difference between the tensile and compressive moduli in the direction of the prepreg fibers.Compressivetensile stress distribution coefficients were also established.Combined with tests on the effect of process parameters on interlayer tack,a theoretical prediction model for the turning radius related to process parameters was developed,and the impact of prepreg interlayer tack force on the minimum turning radius was analyzed.A finite element simulation model for prepreg curve placement was created to study the size and distribution patterns of folds generated during the prepreg turning process.A minimum turning radius test was conducted to establish evaluation criteria for surface defects in curve placement and verify the accuracy of the minimum turning radius prediction model.Based on this,a prediction method for the minimum turning radius of prepreg related to process parameters was established,providing constraints for the trajectory design of variable-stiffness placement composites.展开更多
文摘<strong>Background:</strong> Placenta extract is used as an alternative medicine especially in Asian countries as it is a rich reservoir of diverse bioactive molecules. The effects of placenta extract on skin conditions have been previously reported, however, the mechanism underlying for reduced wrinkle formation remains unclear. <strong>Objective:</strong> The primary objective of this study was to determine whether the continuous application of porcine placenta extract (PPE) alleviates wrinkle formation in humans and explore the underlying mechanism. <strong>Methods:</strong> Wrinkle formation, skin hydration, and skin elasticity were measured in 15 volunteers at weeks 0 and 6 after continuous application of a gel containing PPE. The production of type I collagen and hyaluronic acid from fibroblasts and keratinocytes, respectively, were measured using ELISA. Expression levels of ceramide synthase 3 (CERS3), filaggrin (FLG), transglutaminase 1 (TGM1), and kallikrein-7 (KLK7) were evaluated by quantitative real-time PCR. <strong>Results:</strong> The wrinkle index was significantly reduced to 72.1% after a 6-week of applying the PPE gel, along with a significant increase in skin hydration to 126.5%. Type I collagen production from fibroblasts was enhanced slightly but significantly following treatment with PPE. PPE accelerated the expression of CERS3 (1.85-fold), FLG (1.35-fold), TGM1 (1.76-fold), and KLK7 (1.62-fold). <strong>Conclusion:</strong> Treatment with PPE alleviates wrinkle formation and simultaneously enhances skin hydration, which is induced via the accelerated expression of moisturizing-related proteins. These findings suggest that PPE is effective for combating dryness-induced wrinkle formation.
基金co-supported by the National Natural Science Foundation of China(Nos.U24A20118,52175311,52175133,12472131,52405149)the Fundamental Research Funds for the Central Universities,China(Nos.JZ2023HGPB0289,JZ2023HGQA0475,PA2024GDSK0063)the Anhui Provincial Natural Science Foundation,China(No.2408085QE156)。
文摘The planar force model of prepreg,initially established based on the principle of minimum potential energy and the Rayleigh-Ritz method,was improved by considering the difference between the tensile and compressive moduli in the direction of the prepreg fibers.Compressivetensile stress distribution coefficients were also established.Combined with tests on the effect of process parameters on interlayer tack,a theoretical prediction model for the turning radius related to process parameters was developed,and the impact of prepreg interlayer tack force on the minimum turning radius was analyzed.A finite element simulation model for prepreg curve placement was created to study the size and distribution patterns of folds generated during the prepreg turning process.A minimum turning radius test was conducted to establish evaluation criteria for surface defects in curve placement and verify the accuracy of the minimum turning radius prediction model.Based on this,a prediction method for the minimum turning radius of prepreg related to process parameters was established,providing constraints for the trajectory design of variable-stiffness placement composites.
