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Hypoxia elicits a multitude of tissue responses depending on the severity and duration of the exposure. While chronic hypoxia is shown to impact development, regeneration, and cancer, the understanding of the threats of acute (i.e., short‐term) hypoxia is limited mainly due to its transient nature. Here, a novel gelatin‐dextran (Gel‐Dex) hydrogel is established that decouples hydrogel formation and oxygen consumption and thus facilitates 3D sprouting from endothelial spheroids and, subsequently, induces hypoxia “on‐demand.” The Gel‐Dex platform rapidly achieves acute moderate hypoxic conditions without compromising its mechanical properties. Acute exposure to hypoxia leads to increased endothelial cell migration and proliferation, promoting the total length and number of vascular sprouts. This work finds that the enhanced angiogenic response is mediated by reactive oxygen species, independently of hypoxia‐inducible factors. Reactive oxygen species‐dependent matrix metalloproteinases activity mediated angiogenic sprouting is observed following acute hypoxia. Overall, the Gel‐Dex hydrogel offers a novel platform to study how “on‐demand” acute moderate hypoxia impacts angiogenesis, with broad applicability to the development of novel sensing technologies. In this work, the authors develop a hydrogel platform that rapidly induces acute moderate hypoxia “on‐demand” without compromising its mechanical properties. This platform initially facilitates the establishment of 3D endothelial sprouts that are subsequently exposed to acute hypoxia. The elevated production of reactive oxygen species allows for matrix degradation, enhancing cell migration and proliferation, and promoting angiogenesis from the existing 3D sprouts.

Microcystin-leucine arginine (MC-LR), ubiquitous in water and food, is a threat to public health. In the present study, after C57BL/6J mice were fed with environmental concentrations of MC-LR (0, 1, 30, 60, 90, and 120 μg/L) for 6, 9, and 12 months, it was found that MC-LR could enter into mouse lung tissues and cause microstructural damage, as shown by western blotting and HE staining. Electron microscopy examination showed that MC-LR could damage the lung barrier by disruption of the tight junctions, which was confirmed by the decreased expression of tight junction markers, including Occludin, Claudin1, and ZO-1. In addition, MC-LR also increased the ubiquitination of Claudin1, indicating that MC-LR could disrupt tight junctions by promoting the degradation of Claudin1. Furthermore, MC-LR increased the levels of TNF-α and IL-6 in mouse lung tissues, leading to pneumonia. Importantly, pretreatment with PP2A activator D-erythro-sphingosine (DES) was found to significantly alleviate MC-LR-induced decrease of Occludin and Claudin1 by inhibiting the P-AKT/Snail pathway in vitro. Together, this study revealed that chronic exposure to MC-LR causes lung barrier damage, which involves PP2A activity inhibition and enhancement of Claudin1 ubiquitination. This study broadens the awareness of the toxic effects of MC-LR on the respiratory system, which has deep implications for public health.

Solar-driven interfacial evaporation technology stands out as a promising solution for sustainable freshwater production. To achieve sustained and efficient water evaporation, it is crucial to carefully modulate the distribution of water content within the solar evaporator. In this study, a novel light-temperature responsive composite hydrogel-based solar evaporator was successful constructed. This involved the incorporation of a hydrophilic backbone (polyacrylamide) and a highly efficient solar absorber (multi-walled carbon nanotubes) into a temperature-sensitive hydrogel polymer backbone (poly (N, N-diethylacrylamide)). Due to its low critical solution temperature, the evaporator can undergo a hydrophilic/hydrophobic phase transition alternating day and night conditions. In natural sunlight, the upper hydrogel evaporation region is rendered hydrophobic, minimizing heat loss and preventing salt crystallization. Simultaneously, the bottom water delivery region is hydrophilic to ensure sufficient water supply. At night, the evaporator absorbs water and dissolves, thereby facilitating the rapid return of highly concentrated brine. Leveraging the spontaneously formed Janus structure, the photo-hydrothermal hydrogel achieves an impressive evaporation rate of 2.74 kg m−2h−1and exhibits excellent salt resistance. The notable water evaporation performance and robust salt resistance provide exciting possibilities for achieving ultrafast solar water purification.

Luminescent wood materials are an emerging class of biomass hybrid host materials owing to the hierarchical porous structure and functionalization versatility. The fluorescence properties are largely dependent on exogenous fluorophores, which are, however, often plagued by notorious aggregation effects. In this work, an efficient strategy for the preparation of luminescent transparent wood materials is developed by incorporating tetraphenylethylene-derived aggregation-induced emission (AIE)-active fluorophores during a delignification-backfill transparency process. These wood hybrids showed unexpected luminescence enhancement that significantly increased the fluorescence quantum yield of the fluorophores up to 99%, much higher than that of the fluorophores in other states such as crystalline solids or doped in a polymer substrate. Mechanistic investigations reveal that in situpolymerization of prepolymerized methyl methacrylate in delignified microporous wood frames produces high molecular weight ordered PMMA polymers, resulting in a rigid molecular environment that improves the luminescence efficiency of TPE-based fluorophores at the interfaces of PMMA polymer and cell walls. By confocal laser scanning microscopy (CLSM), this excellent fluorescence staining capability was furthermore utilized to visualize the intrinsic porous network of wood in three dimensions over a large volume with submicrometer resolution, thus providing an alternative approach to the study of structure–function relationships in such wood hybrids.

Cardiovascular disease remains the leading cause of mortality worldwide. The inability of cardiac tissue to regenerate after an infarction results in scar tissue formation, leading to cardiac dysfunction. Therefore, cardiac repair has always been a popular research topic. Recent advances in tissue engineering and regenerative medicine offer promising solutions combining stem cells and biomaterials to construct tissue substitutes that could have functions similar to healthy cardiac tissue. Among these biomaterials, plant‐derived biomaterials show great promise in supporting cell growth due to their inherent biocompatibility, biodegradability, and mechanical stability. More importantly, plant‐derived materials have reduced immunogenic properties compared to popular animal‐derived materials (e.g., collagen and gelatin). In addition, they also offer improved wettability compared to synthetic materials. To date, limited literature is available to systemically summarize the progression of plant‐derived biomaterials in cardiac tissue repair. Herein, this paper highlights the most common plant‐derived biomaterials from both land and marine plants. The beneficial properties of these materials for tissue repair are further discussed. More importantly, the applications of plant‐derived biomaterials in cardiac tissue engineering, including tissue‐engineered scaffolds, bioink in 3D biofabrication, delivery vehicles, and bioactive molecules, are also summarized using the latest preclinical and clinical examples. Plant‐derived biomaterials display promising prospects in cardiac tissue repair. This review highlights the potential and advances of plant‐derived biomaterials in cardiac tissue engineering with the latest examples, which sheds light on developing plant‐derived biomaterials to treat cardiovascular diseases, providing a new strategy for cardiac repair.

We report herein an organic charge transfer cocrystal complex, consisting of a stable radical TPVrand an electron acceptor TCNQF4, as a rare sort of all-organic-based magnetic bistable materials with a thermally activated magnetic hysteresis loop over the temperature range from 170 to 260 K. Detailed X-ray crystallographic studies and theoretical calculations revealed that while a π-associated radical anion dimer was formed upon an integer charge transfer process from TPVrto the TCNQF4molecules within the cocrystal lattice, the resulting TCNQF4·–π-dimers were found to exhibit varied intradimer π-stacking distances and singly occupied molecular orbital overlaps at different temperatures, thus yielding two different singlet states with distinct singlet–triplet gaps above and below the loop, which eventually contributed to the thermally excited molecular magnetic bistability.