Core Viewpoint - The article discusses the development of a biodegradable biohydrogel battery that addresses the limitations of traditional batteries in biomedical applications, emphasizing the need for high-performance energy sources that are compatible with biological systems [4][7]. Group 1: Biohydrogel Battery Development - Researchers from Zhejiang University have designed a biodegradable biohydrogel battery using light polymerization and 3D printing techniques, showcasing excellent mechanical properties and biocompatibility [4]. - The biohydrogel battery operates at a voltage of 1.5 V, providing a current range of 0.001-6 mA, which supports tissue regeneration and cardiac pacing applications [4][8]. Group 2: Hydrogel Characteristics and Applications - Hydrogels, as three-dimensional cross-linked polymer networks, exhibit properties similar to biological tissues, making them suitable for various biomedical applications such as drug delivery and tissue engineering [6]. - The integration of gallium-based liquid metals with hydrogels enhances their conductivity and mechanical performance, promoting their use in flexible bioelectronic devices [6]. Group 3: Challenges and Solutions in Energy Systems - Traditional batteries face significant limitations in biomedical applications due to poor biocompatibility, non-degradability, and rigidity, which can harm surrounding tissues [7]. - The development of a flexible, biodegradable power source using conductive ion hydrogels and InGa3-Cu nanoparticles addresses these challenges, maintaining stable current during degradation [7]. Group 4: Performance Metrics - The biohydrogel battery features a high printing precision of 50 micrometers, with tensile strain and compression rates of 200% and 95%, respectively, aligning with the mechanical properties of biological tissues [8]. - It operates in dual current modes, facilitating microcurrent for tissue regeneration and high current for effective cardiac pacing [8].

Core Insights - A new study published in "Nature Cell Biology" reveals that human cells can change their shape to close wound gaps, providing insights into cellular self-repair mechanisms and potential applications in wound healing and tissue regeneration [1] Group 1: Cellular Mechanisms - Epithelial cells, which cover internal and external surfaces of the body, play a crucial role in protecting against physical damage, pathogen invasion, and water loss [1] - The endoplasmic reticulum (ER) in epithelial cells alters its shape in response to wound curvature; it forms tubular structures at convex curves and flat sheet-like structures at concave curves [1] Group 2: Cellular Movement - The driving force at the edges of convex curves and the pulling force at concave curves change the shape of the endoplasmic reticulum through different mechanisms [1] - At the edges of convex cracks, cells extend flat membrane structures through "crawling" movements to fill the gap, while at concave edges, cells contract the edges through "tethering" movements, akin to tightening a rope to close the gap [1] Group 3: Role of Endoplasmic Reticulum - The endoplasmic reticulum reorganizes itself based on the curvature of the wound edges, influencing the migration patterns of epithelial cells, highlighting its critical role in cellular behavior [1]