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Here we designed enantiomeric lipid‐mimetic glutamic acid derivatives (L/D‐UG) and investigated their self‐assembled chiral nanostructures' interaction with the protein adsorption as well as the osteogenesis. It was found that L or D‐UG molecules can self‐assemble into vesicle bilayers and two‐dimensional (2D) nanocrystals via a kinetic and thermodynamic control, respectively. These chiral vesicles and 2D crystals showed differentiated adsorption of proteins, determined by their curvature and chirality. Specifically, fibronectin constituted by L‐amino acids adsorbed preferentially on L‐UG 2D crystal in a semi‐random pattern and L‐2D nanocrystal show as the most effective structures to promote bone regeneration. The controlled vesicle and 2D crystal assemblies with different chirality and curvature helps to clarify their determine roles in protein adsorption and osteogenesis. [ABSTRACT FROM AUTHOR]

Titanosilicate with H2O2 stands out as a highly consequential oxidized catalytic system, prized for its user‐friendly operation, mild conditions, and eco‐friendly attributes. However, a synthesis strategy for large surface area titanosilicalites approaching the theoretical lowest Si/Ti ratio without extra‐framework Ti species remains an ongoing challenge. In this study, we successfully synthesized single‐crystalline Ti‐rich nanosized aggregated TS‐1 by shielding effect with a Si/Ti polymer. This polymer demonstrated effectiveness in restraining TiO2 species by regulating the proximity of Si/Ti species in Ti‐Diol‐Si polymers. The polymer not only facilitated the synthesis of single‐crystalline Ti‐rich TS‐1 but also exploited the chain length of PEG, functioning as a shielding cage by hydrogen bonds, to synthesize nanosized aggregated TS‐1 (TS‐1‐PEG400). This TS‐1‐PEG400 exhibited superior conversion (~60%), selectivity (~90%), and stability in 1‐hexene epoxidation. This study not only establishes a synthesis pathway for Ti‐rich TS‐1 but also holds the potential to enhance related industrial oxidation reactions involving titanosilicates and H2O2. [ABSTRACT FROM AUTHOR]

Angiogenesis is crucial for successful bone defect repair. Co‐transplanting Bone Marrow Stromal Cells (BMSCs) and Endothelial Cells (ECs) has shown promise for vascular augmentation, but it face challenges in hostile tissue microenvironments, including poor cell survival and limited efficacy. In this study, the mitochondria of human BMSCs are isolated and transplanted to BMSCs from the same batch and passage number (BMSCsmito). The transplanted mitochondria significantly boosted the ability of BMSCsmito‐ECs to promote angiogenesis, as assessed by in vitro tube formation and spheroid sprouting assays, as well as in vivo transplantation experiments in balb/c mouse and SD rat models. The Dll4‐Notch1 signaling pathway is found to play a key role in BMSCsmito‐induced endothelial tube formation. Co‐transplanting BMSCsmito with ECs in a rat cranial bone defect significantly improves functional vascular network formation, and improve bone repair outcomes. These findings thus highlight that mitochondrial transplantation, by acting through the DLL4‐Notch1 signaling pathway, represents a promising therapeutic strategy for enhancing angiogenesis and improving bone repair. Hence, mitochondrial transplantation to BMSCS as a therapeutic approach for promoting angiogenesis offers valuable insights and holds much promise for innovative regenerative medicine therapies. [ABSTRACT FROM AUTHOR]

Cluster aggregation states are thermodynamically favored at the subnanoscale, for which an inverse growth from nanoparticles to clusters may be realized on subnanometer supports. Herein, we develop Au‐polyoxometalate‐layered double hydroxide (Au‐POM‐LDH) sub‐1 nm nanosheets (Sub‐APL) based on the above strategy, where sub‐1 nm Au clusters with negative valence are generated by the in situ disintegration of Au nanoparticles on POM‐LDH supports. Sub‐1 nm Au clusters with ultrahigh surface atom ratios exhibit remarkable efficiency for glutathione (GSH) depletion. The closely connected sub‐1 nm Au with negative valence and POM hetero‐units can promote the separation of hole‐electrons, resulting in the enhanced reactive oxygen species (ROS) generation under ultrasound (US). Besides, the reversible redox of Mo in POM is able to deplete GSH and trigger chemodynamic therapy (CDT) simultaneously, further enhancing the oxidative stress. Consequently, the Sub‐APL present 2‐fold ROS generation under US and 7‐fold GSH depletion compared to the discrete Au and POM‐LDH mixture. Therefore, the serious imbalance of redox in the TME caused by the sharp increase of ROS and rapid decrease of GSH leads to death of tumor ultimately. [ABSTRACT FROM AUTHOR]

Radiotherapy plays a vital role in cancer therapy. However, the hypoxic microenvironment of tumors greatly limits the effectiveness, thus it is crucial to develop a simple, efficient, and safe radiosensitizer to reverse hypoxia and ameliorate the efficacy of radiotherapy. Inspired by the structure of canonical nanodrug Abraxane, herein, a native HSA‐modified CaO2 nanoparticle system (CaO2‐HSA) prepared by biomineralization‐induced self‐assembly is developed. CaO2‐HSA will accumulate in tumor tissue and decompose to produce oxygen, altering the hypoxic condition inside the tumor. Simultaneously, ROS and calcium ions will lead to calcium overload and further trigger immunogenic cell death. Notably, its sensitizing enhancement ratio (SER = 3.47) is much higher than that of sodium glycididazole used in the clinic. Furthermore, in animal models of in situ oral cancer, CaO2‐HSA can effectively inhibit tumor growth. With its high efficacy, facile preparation, and heavy‐metal free biosafety, the CaO2‐HSA‐based radiosensitizer holds enormous potential for oral cancer therapy. [ABSTRACT FROM AUTHOR]

Background/Objectives: Glass, bone, and dentin are commonly applied substrates for osteoclast cultures; however, the impact of these substrates on osteoclastogenesis remains underexplored. This study aimed to address a significant gap in understanding how different substrates influence the process of osteoclastogenesis. Methods: RAW 264.7 cells were cultured and induced with RANKL on glass, bone, and dentin slides. Histological and molecular techniques were used to identify patterns and differences in osteoclast behavior on each substrate. Results: Osteoclasts cultured on glass slides possessed the greatest number of nuclei and the highest expression levels of ACP5 (TRAP) and CTSK, with osteoclasts on bone and dentin slides displaying progressively lower levels. Src expression was also most pronounced in osteoclasts on glass slides, with decreased levels observed on bone and dentin. This variation in Src expression likely contributed to differences in cytoskeletal remodeling and oxidative phosphorylation (OXPHOS), resulting in substrate-dependent divergences in osteoclastogenesis. Conclusions: Glass slides were the most favorable substrate for inducing osteoclastogenesis, while bone and dentin slides were less effective. The substrate-induced expression of Src played a fundamental role in shaping the phenotypic divergence of osteoclasts. These insights fill important knowledge gaps and have significant implications for the development and selection of in vitro models for bone-related diseases and drug screening platforms. [ABSTRACT FROM AUTHOR]

Due to the difficulty of forming a low Schottky barrier at the interface of a metal/SiC contact, preparing Ohmic contacts is still a key technical problem in developing SiC devices. In this paper, the effects of MoS2 intercalation on the interface properties of metal/SiC (Al, Ag, Ti, Au, and Mg) systems were investigated by first-principles calculation. The calculations show that all the metal/SiC contacts exhibit p-type Schottky contacts with strong Fermi level pinning (FLP) at the interfaces. After inserting a layer of MoS2, the Schottky barrier heights are significantly reduced. All the metal/MoS2/SiC systems are tuned to be n-type Ohmic contacts. By calculating and analyzing electron localization functions, projected band structure, partial density of states, and planar-averaged charge density difference, the Ohmic contact formation mechanism may be due to the saturation of dangling bonds of the SiC surface, the reduction in metal-induced gap states, the formation of interface dipole layer, and the shift of FLP position to the interface of metal/MoS2. [ABSTRACT FROM AUTHOR]