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The direct photocatalytic reduction of CO 2 in air is the future trend of photocatalyst application. Herein, the 0D carbon nitride quantum dots with nitrogen vacancies (V N -CNQDs) and 2D bismuth-deficient Bi 4 O 5 Br 2 (V Bi -Bi 4 O 5 Br 2 ) are integrated by hydrothermal method. The S-scheme heterostructure of V N -CNQDs/V Bi -Bi 4 O 5 Br 2 composite promotes the separation rate of photogenerated carriers and enhances the redox capacity. The dual defects provide a large number of adsorption and catalytic sites that enhance the ability to capture and reduce CO 2 . The synergistic effect of S-scheme heterostructure and defect engineering enables the efficiency of CO 2 photoreduction to CO with V N -CNQDs/V Bi -Bi 4 O 5 Br 2 to reach 16.89 µmol g -1  h -1 in air and 55.69 µmol g -1  h -1 in V CO2 : V Air = 3:1 condition, which is 17 and 21 times higher than that of Bi 4 O 5 Br 2 , respectively. The dual-defective V N -CNQDs/V Bi -Bi 4 O 5 Br 2 exhibits more lower energy barrier for forming * CO 2 , * COOH, and * CO and is easier to release CO gas. And it exhibits excellent cycling stability for photocatalytic CO 2 reduction to CO. The photocatalytic reduction mechanism of CO 2 to CO in the V N -CNQDs/V Bi -Bi 4 O 5 Br 2 S-scheme heterostructure is further analyzed. This work provides new perspectives for the design of the photocatalysts with defect engineering for efficient photoconversion at low CO 2 concentrations., (© 2024 Wiley‐VCH GmbH.)

Mismatched reaction kinetics of CO 2 reduction and H 2 O oxidation is the main obstacle limiting the overall photocatalytic CO 2 conversion. Here, a molten salt strategy is used to construct tubular triazine-based carbon nitride (TCN) with more adsorption sites and stronger activation capability. Ni(OH) 2 nanosheets are then grown over the TCN to trigger a proton-coupled electron transfer for a stoichiometric overall photocatalytic CO 2 conversion via "3CO 2 + 2H 2 O = CH 4 + 2CO + 3O 2 ." TCN reduces the energy barrier of H 2 O dissociation to promote H 2 O oxidation to O 2 and supply sufficient protons to Ni(OH) 2 , whereby the CO 2 conversion is accelerated due to the enhanced proton-coupled electron transfer process enabled by the sufficient proton supply from TCN. This work highlights the importance of matching the reaction kinetics of CO 2 reduction and H 2 O oxidation by proton-coupled electron transfer on stoichiometric overall photocatalytic CO 2 conversion., (© 2024 Wiley‐VCH GmbH.)

The one-step assembly of metal-phenolic networks (MPNs) onto particle templates can enable the facile, rapid, and robust construction of hollow microcapsules. However, the required template removal step may affect the refilling of functional species in the hollow interior space or the in situ encapsulation of guest molecules during the formation of the shells. Herein, a simple strategy for the one-step generation of functional MPNs microcapsules is proposed. This method uses bovine serum albumin microbubbles (BSA MBs) as soft templates and carriers, enabling the efficient pre-encapsulation of guest species by leveraging the coordination assembly of tannic acid (TA) and Fe III ions. The addition of TA and Fe III induces a change in the protein conformation of BSA MBs and produces semipermeable capsule shells, which allow gas to escape from the MBs without template removal. The MBs-templated strategy can produce highly biocompatible capsules with controllable structure and size, and it is applicable to produce other MPNs systems like BSA-TA-Cu II and BSA-TA-Ni II . Finally, those MBs-templated MPNs capsules can be further functionalized or modified for the loading of magnetic nanoparticles and the pre-encapsulation of model molecules through covalence or physical adsorption, exhibiting great promise in biomedical applications., (© 2023 Wiley-VCH GmbH.)

Rspos (R-spondins) belong to a family of secreted proteins that causes various cancers via interacting the corresponding receptors. However, targeted therapeutic approaches against Rspos are largely lacking. In this study, a chimeric protein Rspo-targeting anticancer chimeric protein (RTAC) is originally designed, engineered, and characterized. RTAC shows satisfactory anticancer effects through inhibition of pan-Rspo-mediated Wnt/β-catenin signaling activation both in vitro and in vivo. Furthermore, a conceptually novel antitumor strategy distinct from traditional drug delivery systems that release drugs inside tumor cells is proposed. A special "firewall" nano-system is designed to enrich on tumor cell surface and cover the plasma membrane, rather than undergoing endocytosis, to block oncogenic Rspos from binding to receptors. Cyclic RGD (Arg-Gly-Asp) peptide-linked globular cluster serum albumin nanoparticles (SANP) are integrated as a vehicle for conjugating RTAC (SANP-RTAC/RGD) for tumor tissue targeting. These nanoparticles can adhere to the tumor cell surface and enable RTAC to locally capture free Rspos with high spatial efficiency and selectivity to antagonize cancer progression. Therefore, this approach offers a new nanomedical anticancer route and obtains the "dual-targeting" capability for effective tumor clearance and low potential toxicity. This study presents a proof-of-concept for anti-pan-Rspo therapy and a nanoparticle-integrated paradigm for targeted cancer treatment., (© 2023 Wiley-VCH GmbH.)

Periodontium supports teeth in a mechanically stimulated tissue environment, where heterogenous stem/progenitor populations contribute to periodontal homeostasis. In this study, Leptin receptor+ (Lepr+) cells are identified as a distinct periodontal ligament stem cell (PDLSC) population by single-cell RNA sequencing and lineage tracing. These Lepr+ PDLSCs are located in the peri-vascular niche, possessing multilineage potential and contributing to tissue repair in response to injury. Ablation of Lepr+ PDLSCs disrupts periodontal homeostasis. Hyper-loading and unloading of occlusal forces modulate Lepr+ PDLSCs activation. Piezo1 is demonstrated that mediates the mechanosensing of Lepr+ PDLSCs by conditional Piezo1-deficient mice. Meanwhile, Yoda1, a selective activator of Piezo1, significantly accelerates periodontal tissue growth via the induction of Lepr+ cells. In summary, Lepr marks a unique multipotent PDLSC population in vivo, to contribute toward periodontal homeostasis via Piezo1-mediated mechanosensing., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Nickel-iron based hydroxides have been proven to be excellent oxygen evolution reaction (OER) electrocatalysts, whereas they are inactive toward hydrogen evolution reaction (HER), which severely limits their large-scale applications in electrochemical water splitting. Herein, a heterostructure consisted of NiFeV hydroxide and iron oxide supported on iron foam (NiFeV@FeO x /IF) has been designed as a highly efficient bifunctional (OER and HER) electrocatalyst. The V doping and intimate contact between NiFeV hydroxide and FeO x not only improve the entire electrical conductivity of the catalyst but also afford more high-valence Ni which serves as active sites for OER. Meanwhile, the introduction of V and FeO x reduces the electron density on lattice oxygen, which greatly facilitates desorption of H ads . All of these endow the NiFeV@FeO x /IF with exceptionally low overpotentials of 218 and 105 mV to achieve a current density of 100 mA cm -2 for OER and HER, respectively. More impressively, the electrolyzer requires an ultra-low cell voltage of 1.57 V to achieve 100 mA cm -2 and displays superior electrochemical stability for 180 h, which outperforms commercial RuO 2 ||Pt/C and most of the representative catalysts reported to date. This work provides a unique route for developing high-efficiency electrocatalyst for overall water splitting., (© 2023 Wiley-VCH GmbH.)

Stiffness is an important physical property of biomaterials that determines stem cell fate. Guiding stem cell differentiation via stiffness modulation has been considered in tissue engineering. However, the mechanism by which material stiffness regulates stem cell differentiation into the tendon lineage remains controversial. Increasing evidence demonstrates that immune cells interact with implanted biomaterials and regulate stem cell behaviors via paracrine signaling; however, the role of this mechanism in tendon differentiation is not clear. In this study, polydimethylsiloxane (PDMS) substrates with different stiffnesses are developed, and the tenogenic differentiation of mesenchymal stem cells (MSCs) exposed to different stiffnesses and macrophage paracrine signals is investigated. The results reveal that lower stiffnesses facilitates tenogenic differentiation of MSCs, while macrophage paracrine signals at these stiffnesses suppress the differentiation. When exposed to these two stimuli, MSCs still exhibit enhanced tendon differentiation, which is further elucidated by global proteomic analysis. Following subcutaneous implantation in rats for 2 weeks, soft biomaterial induces only low inflammation and promotes tendon-like tissue formation. In conclusion, the study demonstrates that soft, rather than stiff, material has a greater potential to guide tenogenic differentiation of stem cells, which provides comprehensive evidence for optimized bioactive scaffold design in tendon tissue engineering., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Silk fibroin (SF) and sericin (SS), the two major proteins of silk, are attractive biomaterials with great potential in tissue engineering and regenerative medicine. However, their biochemical interactions with stem cells remain unclear. In this study, multiomics are employed to obtain a global view of the cellular processes and pathways of mesenchymal stem cells (MSCs) triggered by SF and SS to discern cell-biomaterial interactions at an in-depth, high-throughput molecular level. Integrated RNA sequencing and proteomic analysis confirm that SF and SS initiate widespread but distinct cellular responses and potentiate the paracrine functions of MSCs that regulate extracellular matrix deposition, angiogenesis, and immunomodulation through differentially activating the integrin/PI3K/Akt and glycolysis signaling pathways. These paracrine signals of MSCs stimulated by SF and SS effectively improve skin regeneration by regulating the behavior of multiple resident cells (fibroblasts, endothelial cells, and macrophages) in the skin wound microenvironment. Compared to SS, SF exhibits better immunomodulatory effects in vitro and in vivo, indicating its greater potential as a carrier material of MSCs for skin regeneration. This study provides comprehensive and reliable insights into the cellular interactions with SF and SS, enabling the future development of silk-based therapeutics for tissue engineering and stem cell therapy., (© 2023 Wiley-VCH GmbH.)

An overall carbon-neutral CO 2 electroreduction requires enhanced conversion efficiency and intensified functionality of CO 2 -derived products to balance the carbon footprint from CO 2 electroreduction against fixed CO 2 . A liquid Sn cathode is herein introduced into electrochemical reduction of CO 2 in molten salts to fabricate core-shell Sn-C spheres (Sn@C). An in situ generated Li 2 SnO 3 /C directs a self-template formation of Sn@C. Benefitting from the accelerated reaction kinetics from the liquid Sn cathode and the core-shell structure of Sn@C, a CO 2 -fixation current efficiency higher than 84 % and a high reversible lithium-storage capacity of Sn@C are achieved. The versatility of this strategy is demonstrated by other low melting point metals, such as Zn and Bi. This process integrates energy-efficient CO 2 conversion and template-free fabrication of value-added metal-carbon, achieving an overall carbon-neutral electrochemical reduction of CO 2 ., (© 2022 Wiley-VCH GmbH.)

Frizzled (Fzd) proteins are Wnt receptors and play essential roles in development, homeostasis, and oncogenesis. How Wnt/Fzd signaling is coupled to physiological regulation remains unknown. Cholesterol is reported as a signaling molecule regulating morphogen such as Hedgehog signaling. Despite the elusiveness of the in-depth mechanism, it is well-established that pancreatic cancer specially requires abnormal cholesterol metabolism levels for growth. In this study, it is unexpectedly found that among ten Fzds, Fzd5 has a unique capacity to bind cholesterol specifically through its conserved extracellular linker region. Cholesterol-binding enables Fzd5 palmitoylation, which is indispensable for receptor maturation and trafficking to the plasma membrane. In Wnt-addicted pancreatic ductal adenocarcinoma (PDAC), cholesterol stimulates tumor growth via Fzd5-mediated Wnt/β-catenin signaling. A natural oxysterol, 25-hydroxylsterol competes with cholesterol and inhibits Fzd5 maturation and Wnt signaling, thereby alleviating PDAC growth. This cholesterol-receptor interaction and ensuing receptor lipidation uncover a novel mechanism by which Fzd5 acts as a cholesterol sensor and pivotal connection coupling lipid metabolism to morphogen signaling. These findings further suggest that cholesterol-targeting may provide new therapeutic opportunities for treating Wnt-dependent cancers., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

Osteochondral defects are characterized by injuries to both cartilage and subchondral bone, which is a result of trauma, inflammation, or inappropriate loading. Due to the unique biological properties of subchondral bone and cartilage, developing a tissue engineering scaffold that can promote dual-lineage regeneration of cartilage and bone simultaneously remains a great challenge. In this study, a microporous nanosilicate-reinforced enzymatically crosslinked silk fibroin (SF) hydrogel is fabricated by introducing montmorillonite (MMT) nanoparticles via intercalation chemistry. In vitro studies show that SF-MMT nanocomposite hydrogel has improved mechanical properties and hydrophilicity, as well as the bioactivities to promote the osteogenic differentiation of bone marrow mesenchymal stem cells and maintain chondrocyte phenotype compared with SF hydrogel. Global proteomic analysis verifies the dual-lineage bioactivities of SF-MMT nanocomposite hydrogel, which are probably regulated by multiple signaling pathways. Furthermore, it is observed that the biophysical interaction of cells and SF-MMT nanocomposite hydrogel is partially mediated by clathrin-mediated endocytosis and its downstream processes. In vivo, the SF-MMT nanocomposite hydrogel effectively promotes osteochondral regeneration as evidenced by macroscopic, micro-CT, and histological evaluation. In conclusion, a functionalized SF-MMT nanocomposite hydrogel is developed with dual-lineage bioactivity for osteochondral regeneration, indicating its potential in osteochondral tissue engineering., (© 2022 Wiley-VCH GmbH.)

Two dimeric prenylindole alkaloids with a unique indole-benzoindolequinone skeleton, cimicifoetones A (1) and B (2), were isolated as black pigments from the rhizomes of Cimicifuga foetida. The structures were elucidated by spectroscopic methods including HRMS and 2D NMR, as well as single-crystal X-ray diffraction and computational chemical modeling techniques. Cimicifoetones A and B represented the first examples of dimeric indole alkaloids generated through [4+2] Diels-Alder cycloaddition between the prenyl side chain in one 3-prenylindole and the aromatic ring in another. The two compounds showed promising anti-proliferative activity on seven tumor cell lines with IC 50 values in the range of 1.36-21.09 μm. Flow cytometric and western blot analysis revealed that compound 2 induced cell apoptosis via death receptor-mediated extrinsic and mitochondrial-mediated intrinsic pathways., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Lipids regulate a wide range of biological activities. Since their local concentrations are tightly controlled in a spatiotemporally specific manner, the simultaneous quantification of multiple lipids is essential for elucidation of the complex mechanisms of biological regulation. Here, we report a new method for the simultaneous in situ quantification of two lipid pools in mammalian cells using orthogonal fluorescent sensors. The sensors were prepared by incorporating two environmentally sensitive fluorophores with minimal spectral overlap separately into engineered lipid-binding proteins. Dual ratiometric analysis of imaging data allowed accurate, spatiotemporally resolved quantification of two different lipids on the same leaflet of the plasma membrane or a single lipid on two opposite leaflets of the plasma membrane of live mammalian cells. This new imaging technology should serve as a powerful tool for systems-level investigation of lipid-mediated cell signaling and regulation., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, we present the preparation of water-soluble poly(methacrylate)s with pendant cationic L-lysines PHMLs(6-30 K). Plasmid DNA binding affinity as well as particle sizes and zeta potentials of the polyplexes were examined for these PHML vectors, and their cytotoxicities were assayed with HeLa cells by CCK-8 and lactate dehydrogenase kits. Gene transfection efficacy and intracellular uptake of the polyplexes by the PHML vectors were also studied with HeLa cells. As a result, it was revealed that the low cytotoxic PHMLs tended to exhibit gene transfection efficiencies significantly higher than those of the linear structural PLL (15-30 K) control, in particular the molecular weight of a PHML vector remarkably influenced its pDNA binding affinity, transfection efficacy and intracellular uptake of the polyplexes., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A new series of triblock [dendritic poly(L-lysine)]-block-PLLA-block-[dendritic poly(L-lysine)]s (DL(2) -PLLA-DL(2) ) with PLLA block lengths of 11.5-26.5 and double 2-generation PLL dendrons DL(2) as model cationic amphiphiles were synthesized and characterized. Their CAC, self-aggregation and plasmid DNA binding affinities in pure water and PBS were studied. The PLLA block length dependence of particle size, morphology and ξ potential for organized pDNA/amphiphile polyplex aggregates were examined. Finally, toxicities of these DL(2) -PLLA-DL(2) amphiphiles and their polyplexes were assayed by MTT with HeLa, SMMC-7721 and COS-7 cells, and COS-7 cell luciferase and eGFP gene transfection efficacies with these amphiphiles as the delivery carriers were investigated., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this work, we prepared a novel series of cationic amphiphiles denoted as the Py-cations (Py-Gly, Py-Ala, Py-Cap, Py-G(1)-Lys and Py-G(2)-Lys) bearing fluorescent pyrene and various hydrocarbon linkers between the pyrene hydrophobe and cationic block. Employing these new cationic amphiphiles with pyrene as the fluorescent probe, the interactions between these Py-cations and plasmid DNA (pDNA) in distilled water and 0.1 M PBS buffer solution have been explored by means of UV-vis and fluorescent spectrometers, and ethidium bromide dye displacement and agarose-gel retardant assays were also implemented to evaluate their pDNA binding affinities in aqueous solution. Furthermore, the average sizes and morphologies of self-assembled Py-cation/pDNA lipoplex aggregates were examined by dynamic laser light scattering (DLS) and atomic force microscopy (AFM). It was found that these fluorescent cationic amphiphiles showed blue fluorescence emission of pyrene probe at λ = 340 nm in distilled water while their interactions with pDNA led to new strong green emission at λ = 490 nm, and this may be due to the stacking of pyrene and new formation of excimers via the rigid pDNA templated self-assembly. It was also revealed that the binding between new Py-cations and pDNA in aqueous solution was strongly influenced by the Py-cation hydrophobicity, charges of the cation and the presence of electrolytes. With respect to the Py-cation/pDNA aggregate morphologies, very interesting 1-D hybrid nanofibers were predominantly observed by AFM for the Py-Cap/pDNA aggregates. In addition, utilizing a COS-7 cell-line, in-vitro cellular uptakes of new cationic amphiphiles with pyrene probe were studied and visualized by fluorescent microscopy. As a result, this may provide a new approach to investigate the interactions between synthetic cationic lipids and nucleic acids, and pave an alternative clue to design new organic gene delivery carriers.