Severe muscle injury is still a challenging clinical problem. Exosomes derived from adipose stem cells (ASC-exos) may be a potential therapeutic tool, but their mechanism is not completely clear. This review aims to elaborate the possible mechanism of ASC-exos in muscle regeneration from the perspective of signal pathways and provide guidance for further study. Literature cited in this review was acquired through PubMed using keywords or medical subject headings, including adipose stem cells, exosomes, muscle regeneration, myogenic differentiation, myogenesis, wingless/integrated (Wnt), mitogen-activated protein kinases, phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B (PI3K/Akt), Janus kinase/signal transducers and activators of transcription, and their combinations. We obtained the related signal pathways from proteomics analysis of ASC-exos in the literature, and identified that ASC-exos make different contributions to multiple stages of skeletal muscle regeneration by those signal pathways.

Objective:To establish a three-dimensional finite element model of the nose, simulate and analyze the deformation of nasal tissue caused by different focal points, traction directions, and modes, provide the theoretical basis for the effectiveness of physical traction therapy, and guide the clinical selection of more efficient physical traction therapy methods.Methods:A finite element model of the nose was established by ANSYS Workbench 19.2 software based on image data obtained from CT scans of a 29-year-old male volunteer with normal nasal appearance in Peking University Third Hospital. Two focal points, the nasal tip, and the nasal columella, were selected, and three force directions, parallel to the forward, forward and down 30°, forward and down 60°, were applied. The deformation caused by different traction conditions on the skin, lining, and soft bone parts, as well as the four anatomical landmarks of the nasal tip, nasal root, the midpoint of the nasal columella, and the nasal base, were compared. The deformation produced by 10 minutes of continuous pulling and 10 times 1-minute pulse pulling were compared under the same pulling conditions. The deformations generated by two types of pulling modes within a 24-hour cycle: a single 1-hour cycle and 6 intermittent 10-minute cycles, were compared.Results:All traction conditions resulted in deformation of the nasal model, with the maximum deformation of the nasal tissue obtained by pulling forward and downward at 60° (4.632 9 mm) which was greater than other traction conditions (0.825 0-3.105 0 mm). The maximum deformation value was located near the nasion of the model’s skin layer. The deformation obtained by 10 minutes of continuous pulling (0.176 6 mm) was slightly greater than that obtained by 10 times of 1-minute pulse pulling (0.176 5 mm). Within 24 hours, the final deformation of multiple intermittent pulling modes (0.019 0 mm) was greater than that of a single pulling mode (0.004 3 mm).Conclusion:Physical traction can effectively deform the skin and soft tissue of the nose, and the most efficient operation is to continuously pinch the tip of the nose for a short period and apply tension parallel to the back of the nose downwards, repeating every a few hours.

Objective:To establish a three-dimensional finite element model of the nose, simulate and analyze the deformation of nasal tissue caused by different focal points, traction directions, and modes, provide the theoretical basis for the effectiveness of physical traction therapy, and guide the clinical selection of more efficient physical traction therapy methods.Methods:A finite element model of the nose was established by ANSYS Workbench 19.2 software based on image data obtained from CT scans of a 29-year-old male volunteer with normal nasal appearance in Peking University Third Hospital. Two focal points, the nasal tip, and the nasal columella, were selected, and three force directions, parallel to the forward, forward and down 30°, forward and down 60°, were applied. The deformation caused by different traction conditions on the skin, lining, and soft bone parts, as well as the four anatomical landmarks of the nasal tip, nasal root, the midpoint of the nasal columella, and the nasal base, were compared. The deformation produced by 10 minutes of continuous pulling and 10 times 1-minute pulse pulling were compared under the same pulling conditions. The deformations generated by two types of pulling modes within a 24-hour cycle: a single 1-hour cycle and 6 intermittent 10-minute cycles, were compared.Results:All traction conditions resulted in deformation of the nasal model, with the maximum deformation of the nasal tissue obtained by pulling forward and downward at 60° (4.632 9 mm) which was greater than other traction conditions (0.825 0-3.105 0 mm). The maximum deformation value was located near the nasion of the model’s skin layer. The deformation obtained by 10 minutes of continuous pulling (0.176 6 mm) was slightly greater than that obtained by 10 times of 1-minute pulse pulling (0.176 5 mm). Within 24 hours, the final deformation of multiple intermittent pulling modes (0.019 0 mm) was greater than that of a single pulling mode (0.004 3 mm).Conclusion:Physical traction can effectively deform the skin and soft tissue of the nose, and the most efficient operation is to continuously pinch the tip of the nose for a short period and apply tension parallel to the back of the nose downwards, repeating every a few hours.