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Multifunctional hydrogel dressings remain highly sought after for the promotion of skin wound regeneration. In the present study, multifunctional CHS-DA/HACC (CH) hydrogels with an interpenetrated network were constructed using hydroxypropyl trimethyl ammonium chloride modified chitosan (HACC) and dopamine-modified chondroitin sulfate (CHS-DA), using genipin as crosslinker. The synthesis of HACC and CHS-DA was effectively confirmed using Fourier transform infrared (FT-IR) analysis and 1H nuclear magnetic resonance (1H NMR) spectroscopy. The prepared CH hydrogels exhibited a network of interconnected pores within the microstructure. Furthermore, rheological testing demonstrated that CH hydrogels exhibited strong mechanical properties, stability, and injectability. Further characterization investigations showed that the CH hydrogels showed favorable self-healing and self-adhesion properties. It was also shown that increasing HACC concentration ratio was positively correlated with the antibacterial activity of CH hydrogels, as evidenced by their resistance to Escherichia coli and Staphylococcus aureus. Additionally, Cell Counting Kit-8 (CCK-8) tests, fluorescent images, and a cell scratch assay demonstrated that CH hydrogels had good biocompatibility and cell migration ability. The multifunctional interpenetrated network hydrogels were shown to have good antibacterial properties, antioxidant properties, stable storage modulus and loss modulus, injectable properties, self-healing properties, and biocompatibility, highlighting their potential as wound dressings in wound healing applications. [ABSTRACT FROM AUTHOR]

Hydrogel have been widely used to promote skin tissue regeneration and accelerate wound healing. The development of injectable hydrogels with multi‐functional integration is a priority, especially with antibacterial properties and cytocompatibility. Here, we reported a simple, and versatile method to fabricate a functional hydrogel with potential for wound dressing applications. The dopamine‐grafted gelatin (GT‐DA) and oxidized dextran (oxyglucan, ODex) were synthesized, and dipotassium glycyrrhizinate (DG) was in situ incorporated to fabricate the composite hydrogels (GDO) through the Schiff base reaction. SEM images revealed that hydrogel has a porous structure. By increasing the ratio of GT‐DA to ODex from 1 to 4, the storage modulus (G') and hydrogel network stability nearly doubled, reaching 900 Pa and 220% strain, respectively. The enhancement in mechanical properties could be attributed to the higher cross‐linking density resulting from increased Schiff base bonds in the GDO hydrogels. Furthermore, the GDO hydrogel exhibited antioxidant activity and antibacterial effects on Escherichia coli and Staphylococcus aureus. Moreover, the hydrogel demonstrated cytocompatibility after culturing with human umbilical vein endothelial cells (HUVECs). The results proved that the fabricated GDO hydrogels have the potential to be used as wound dressings. [ABSTRACT FROM AUTHOR]

Peripheral nerve injury often leads to the loss of neurological functions due to the slow regeneration rate and inefficient functional reconstruction. Current clinical treatments using nerve guidance conduits (NGCs) still face challenges in providing a biomimetic microenvironment to promote nerve repair. Herein, decellularized extracellular matrix (dECM) is obtained from porcine Achilles tendon and crosslinked with 3‐amino‐4‐methoxybenzoic acid grafted gelatin (PAMB‐G) to obtain conductive hydrogels. Then, a novel nerve guidance conduit is developed by assembling poly(vinyl alcohol) (PVA) conduit and conductive ECM@PAMB‐G hydrogel. This bioengineered ECM@PAMB‐G/PVA conduit demonstrated excellent cytocompatibility, electrical conductivity, mechanical properties, and biodegradability. In vitro experiments confirmed that the ECM@PAMB‐G hydrogel significantly promotes the proliferation and migration of PC12 cells and primary Schwann cells, as well as the growth of dorsal root ganglion (DRG) axons. Furthermore, in vivo studies in a rat sciatic nerve model exhibited improvements in axonal regeneration, Schwann cell migration, myelin sheath formation, and functional recovery mediated by the ECM@PAMB‐G/PVA conduit. This work demonstrates the synergistic effects of extracellular matrix and electrical cues in enhancing peripheral nerve regeneration. The ECM@PAMB‐G/PVA nerve guidance conduit shows potential as an alternative to autografts for supporting peripheral nerve reconstruction. [ABSTRACT FROM AUTHOR]

Most studies focused on the above‐ground diversity on leaf litter decomposition and soil respiration in tropical ecosystems, however, the mechanism understanding of root diversity on decomposition is still unclear.We selected the fine‐roots of 21 dominant tree species from a tropical rainforest in Xishuangbannan, China, then conducted a 360‐day and well‐replicated (21 replications) incubation decomposition experiment with a 0, 1, 3, 6, 9, 12, 15, 18 and 21 species gradient of root diversity. The fine‐root mass loss, CO2 release, and their potential drivers were analysed.The results showed that as fine‐root diversity increased, soil properties, microbial diversity and fungal biomass changed nonlinearly, leading to higher litter mass loss and soil CO2 release in the moderate diversity with 9, 12 and 15 species mixtures. Non‐additive effect analysis also indicated that synergistic effects were greater in these three mixtures than others on soil CO2 release and litter mass loss. The indirect effects of soil properties and microbial communities were larger than the direct effect of fine‐root diversity.Our findings suggest that fine‐root diversity has nonlinear relationships with litter decomposition and soil CO2 release in tropical forests, thus highlighting the importance of plant diversity due to its role in the carbon cycle under global change scenario. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

We introduce a 10-fs hyperspectral source architecture for facilitating nonlinear spectroscopy with multi-color sequences of arbitrarily shaped 10-fs UV/Vis, near-IR, and mid-IR pulses. Design principles and initial experimental results are provided.