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Cellular senescence is a significant contributor to intervertebral disc aging and degeneration. However, the application of senotherapies, such as senomorphics targeting senescence markers and the senescence‐associated secretory phenotype (SASP), remains limited due to challenges in precise delivery. Given that the natural killer group 2D (NKG2D) ligands are increased on the surface of senescent nucleus pulposus (NP) cells, the NKG2D‐overexpressing NP cell membranes (NNPm) are constructed, which is expected to achieve a dual targeting effect toward senescent NP cells based on homologous membrane fusion and the NKG2D‐mediated immunosurveillance mechanism. Then, mesoporous silica nanoparticles carrying a peroxisome proliferator‐activated receptor‐ɣ coactivator 1α (PGC1α)inducer (SP) are coated with NNPm (SP@NNPm) and it is found that SP@NNPm selectively targets senescent NP cells, and the SP cores exhibit pH‐responsive drug release. Moreover, SP@NNPm effectively induces PGC1α‐mediated mitochondrial biogenesis and mitigates senescence‐associated markers induced by oxidative stress and the SASP, thereby alleviating puncture‐induced senescence and disc degeneration. This dual‐targeting nanotherapeutic system represents a novel approach to delivery senomorphics for disc degeneration treatment. [ABSTRACT FROM AUTHOR]

With the acceleration of the urban industrialization process, air pollutant emission has increased sharply, which seriously endangers the ecological environment and human beings. Solar-driven photocatalysis has the broad-spectrum activity for various inorganic to organic pollutants at ambient temperature without harsh reaction conditions, which shows a very broad application prospect in air purification. However, the photocatalysis technology suffers from the unrevealed reaction mechanism and the deactivation of photocatalysts, which severely limits its practical application. Currently, there is still a huge gap between basic research and industrial application in the field of photocatalytic air purification. This review summarizes recent progress on photocatalytic degradation of air pollutants and categorizes them based on the types of photocatalytic materials and air pollutants, with a focus on photocatalytic reaction mechanisms and the application scenarios of photocatalytic air purification to identify this gap. We also critically discussed the major challenges for promoting applications of photocatalytic technology and put forward the development prospect.

Intervertebral disc degeneration (IDD) is an age‐related disease and is responsible for low back pain. Oxidative stress‐induced cell death plays a fundamental role in IDD pathogenesis. Cuproptosis is a recently discovered form of programmed cell death dependent on copper availability. Whether cuproptosis is involved in IDD progression remains unknown. Herein, we established in vitro and in vivo models to investigate cuproptosis in IDD and the mechanisms by which oxidative stress interacts with copper sensitivity in nucleus pulposus cells (NPCs). We found that ferredoxin‐1 (FDX1) content increased in both rat and human degenerated discs. Sublethal oxidative stress on NPCs led to increased FDX1 expression, tricarboxylic acid (TCA) cycle‐related proteins lipoylation and aggregation, and cell death in the presence of Cu2+ at physiological concentrations, while FDX1 knockdown inhibited cell death. Since copper homeostasis is involved in copper‐induced cytotoxicity, we investigated the role of copper transport‐related proteins, including importer (CTR1) and efflux pumps (ATPase transporter, ATP7A, and ATP7B). CTR1 and ATP7A content increased under oxidative stress, and blocking CTR1 reduced oxidative stress/copper‐induced TCA‐related protein aggregation and cell death. Moreover, oxidative stress promoted the expression of specific protein 1 (SP1) and SP1‐mediated CTR1 transcription. SP1 inhibition decreased cell death rates, preserved disc hydration, and alleviated tissue degeneration. This suggests that oxidative stress upregulates FDX1 expression and copper flux through promoting SP1‐mediated CTR1 transcription, leading to increased TCA cycle‐related protein aggregation and cuproptosis. This study highlights the importance of cuproptosis in IDD progression and provides a promising therapeutic target for IDD treatment. [ABSTRACT FROM AUTHOR]

Exogenous stem cell therapy and endogenous repair has shown great potential in intervertebral disc regeneration. However, limited nutrients and accumulation of lactate largely impair the survival and regenerative capacity of implanted stem cells and endogenous nucleus pulposus cells (NPCs). Herein, an injectable hydrogel microsphere (LMGDNPs) have been developed by immersing lactate oxidase (LOX)‐manganese dioxide (MnO2) nanozyme (LM) into glucose‐enriched decellularized nucleus pulposus hydrogel microspheres (GDNPs) through a microfluidic system. LMGDNPs showed a delayed release profile of LOX and satisfactory enzymatic capacity in consuming lactate. Mesenchymal stem cells (MSCs) plated on LMGDNPs exhibited better cell viability than cells on GelMA and decellularized nucleus pulposus microspheres (DNP) and showed a obviously increased NPCs phenotype. LMGDNPs prevented MSCs and NPCs death and promoted extracellular matrix synthesis by exhausting lactate. It is determined that LMGDNPs promoted NPCs autophagy by activating transforming growth factor β2 overlapping transcript 1 (TGFB2‐OT1), relying on the nanozyme. MSCs‐loaded LMGDNPs largely preserved disc hydration and alleviated matrix degradation in vivo. Summarily, LMGDNPs promoted cell survival and matrix regeneration by providing a nutrient supply, exhausting lactate, and activating autophagy via TGFB2‐OT1 and its downstream pathway and may serve as an ideal delivery system for exogenous stem cell therapy and endogenous repair. [ABSTRACT FROM AUTHOR]

Cu2O microparticles with controllable crystal planes and relatively high stability have been recognized as a good platform to understand the mechanism of the electrocatalytic CO2 reduction reaction (CO2RR). Herein, we demonstrate that the in situ generated Cu2O/Cu interface plays a key role in determining the selectivity of methane formation, rather than the initial crystal plane of the reconstructed Cu2O microparticles. Experimental results indicate that the methane evolution is dominated on all three different crystal planes with similar Tafel slopes and long‐term stabilities. Density functional theory (DFT) calculations further reveal that *CO is protonated via a similar bridge configuration at the Cu2O/Cu interface, regardless of the initial crystal planes of Cu2O. The Gibbs free energy changes (ΔG) of *CHO on different reconstructed Cu2O planes are close and more negative than that of *OCCOH, indicating the methane formation is more favorable than ethylene on all Cu2O crystal planes. [ABSTRACT FROM AUTHOR]

Defect engineering has been regarded as a versatile strategy to maneuver the photocatalytic activity. However, there are a few studies concerning how to maintain the stability of defects, which is important to ensure sustainable photocatalytic performance. Here, a novel strategy to modulate the structural properties of BiSbO4 using light‐induced dynamic oxygen vacancies is reported by us for efficient and stable photocatalytic oxidation of formaldehyde. Interestingly, the continuous consumption and replenishment of vacancies (namely dynamic vacancies) ensure the dynamic stability of oxygen vacancies, thus guaranteeing the excellent photocatalytic stability. The oxygen vacancies could also accelerate the electron migration, inhibit the photogenerated electron/hole recombination, widen the light absorption spectra, and thus improve the photocatalytic formaldehyde removal performance. Combined with the results of in situ DRIFTS, the reaction mechanism for each step of formaldehyde oxidation is revealed. As supported by DFT calculation of Gibbs free energy, the introduction of oxygen vacancies into BiSbO4 can promote spontaneous process of formaldehyde oxidation. Our work highlights a promising approach for stabilizing the defects and proposes the photocatalytic reaction mechanism in combination with the thermodynamic functions. [ABSTRACT FROM AUTHOR]

Background: Osteosarcoma (OS) is the most widespread bone tumour among childhood cancers, and distant metastasis is the dominant factor in poor prognosis for patients with OS. Therefore, it is necessary to identify new prognostic biomarkers for identifying patients with aggressive disease. Methods: Two OS datasets (GSE21257 and GSE33383) were downloaded from the Gene Expression Omnibus (GEO) and subsequently subjected to weighted gene co-expression network analysis (WGCNA) and differential gene expression analysis (DGE) to screen candidate genes. A prognostic model was constructed using OS data derived from the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) program to further screen key genes and perform gene ontology (GO) analysis. The prognostic values of key genes were assessed using the Kaplan–Meier (KM) plotter. The GEO dataset was used for immune infiltration analysis and association analysis of key genes. In addition, quantitative real-time polymerase chain reaction (qRT-PCR) was employed to validate the expression levels of potentially crucial genes in OS cell lines. Results: In the present study, we found 114 genes with a highly significant correlation in the module and 44 downregulated genes; 25 candidate genes overlapped in the two parts of the genes. Among these, three key genes, C1QA, C1QB, and C1QC, were the most significant hub genes, which had the highest node degrees, were clustered into one group, and implicated in most significant biological processes (regulation of immune effector process). Moreover, these three key genes were negatively associated with the prognosis of OS and positively associated with three immune cells (follicular helper T cells, memory B cells, and CD8 T cells). Additionally, compared to non-metastatic OS cell lines, the expression of three key genes was significantly downregulated in metastatic OS cell lines. Conclusion: Our results revealed that three key genes (C1QA, C1QB, and C1QC) were implicated in tumour immune infiltration and may be promising biomarkers for predicting metastasis and prognosis of patients with OS. [ABSTRACT FROM AUTHOR]

Metal-based cocatalysts have been widely applied in the photocatalytic CO2 reduction reaction (CO2RR) and the integration of cocatalysts/semiconductors is expected to enhance the selectivity of the catalytic reaction. Nevertheless, the type and yield of products manifest a large discrepancy even for the same cocatalyst/semiconductor photocatalytic system, which requires a comprehensive study into the reaction mechanism and product distribution in detail. Here we provide kinetics evidence that selective CO2 reduction into CH4 is realized on Cu loaded carbon nitride (Cu/CN), in comparison with that on Au species (Au/CN) which yield both CO and CH3OH. Besides, it is revealed that the adsorption/desorption thermodynamic behavior of CH3OH is a crucial factor to determine the product distribution. By the establishment of binary electron transfer channels at the interface between adsorbed CH3OH and the Cu/CN surface, intensified activation of CH3OH is accomplished, resulting in the over-all reduction of CO2 into methane. Owing to the combined kinetics and thermodynamics investigation at the atomic level, this work may provide pioneering design schemes of precisely tailored cocatalyst/semiconductor photocatalytic systems for the selective CO2RR. [ABSTRACT FROM AUTHOR]

Surface hydroxyl groups play a decisive role in the generation of hydroxyl radicals with stronger oxidizing ability, which is indispensable in photocatalytic VOCs removal, especially under the condition of low humidity. In this work, non-noble amorphous SnO 2 decorated ZnSn(OH) 6 (ZSH) was synthesized by an in-situ method. The charge transport, reactant activation and hydroxyl polarization are enhanced through decoration of amorphous SnO 2 on ZSH. Combined with the designed experiment, in-situ EPR, DTF calculation and in-situ DRIFTS, the role and mechanism of interfacial hydroxyl polarization are revealed on SnO 2 decorated ZnSn(OH) 6. Compared with pristine ZSH and noble-metal modified ZSH, the toluene degradation rate of amorphous SnO 2 decorated ZSH is increased by 13.0 and 3.8 times, and the toluene mineralization rate is increased by 5.2 and 2.2 times. The ZSH-24 sample maintains a high toluene degradation activity after 6 cyclic utilization without catalyst deactivation. This work emphasizes the role of non-noble metal and the origin of hydroxyl group polarization on ZnSn(OH) 6 for photocatalytic VOCs mineralization. [Display omitted] • Amorphous SnO 2 decorated ZnSn(OH) 6 was synthesized by an in-situ method. • Photocatalytic mineralization of toluene is promoted via SnO 2 decoration. • Amorphous SnO 2 enhances charge transport and reactant activation on ZnSn(OH) 6. • The role and mechanism of hydroxyl polarization are clarified in detail. • The mechanism of photocatalytic toluene mineralization is revealed. [ABSTRACT FROM AUTHOR]

Osteosarcoma (OS) is the pretty common primary cancer of the bone among the malignancies in adolescents. A single molecular component or a limited number of molecules is insufficient as a predictive biomarker of OS progression. Hence, it is necessary to find novel network biomarkers to improve the prediction and therapeutic effect for OS. Here, we identified 230 DE-miRNAs and 821 DE-mRNAs through two miRNA expression-profiling datasets and three mRNA expression-profiling datasets. We found that hsa-miR-494 is closely linked with the survival of OS patients. In addition, we analyzed GO and KEGG enrichment for targets of hsa-miR-494-5p and hsa-miR-494-3p through R programming. And five mRNAs were predicted as common targets of hsa-miR-494-5p and hsa-miR-494-3p. We further revealed that upregulated TRPS1 was strongly correlated with poor outcomes in OS patients through the survival analysis based on the TARGET database. The qRT-PCR study verified that the expression of hsa-miR-494-5p and hsa-miR-494-3p was declined considerably, while TRPS1 was notably raised in OS cells when compared to the osteoblasts. Thus, we generated a new regulatory subnetwork of key miRNAs and target mRNAs using Cytoscape software. These results indicate that the novel miRNA-mRNA subnetwork composed of hsa-miR-494-5p, hsa-miR-494-3p, and TRPS1 might be a characteristic molecule for assessing the prognostic value of OS patients. [ABSTRACT FROM AUTHOR]

[Display omitted] • Delocalized electrons were formed on Bi 2 O 2 CO 3 surface by interlayer hydrogenation. • Stable conjugated structure of benzene-ring was tailored, resulting in destabilization. • Direct ring-opening pathway and deep toluene oxidation were achieved. • The reaction pathway of reactants with un-activated benzene-ring was revealed. The stable conjugated structure of benzene-ring poses the persistent challenge for deep oxidation of toluene. In this study, the electronic structure of benzene-ring-containing reactants is tailored by engineering the interlayer hydrogenation in layered Bi 2 O 2 CO 3 , where charge separation and migration capabilities are improved and the confined charge in the interlayer and intralayer could transfer to catalyst surface and serve as delocalized electrons. The ring-opening site, the C = C bond, is activated by delocalized electrons. Consequently, the conjugated structure of the benzene-ring turns into a state with uneven charge distribution, resulting in weakened stability. With the attack of photo-generated radicals, the destabilized benzene-ring structure can be destroyed with direct ring-opening of toluene and achieves deep oxidation of toluene. Therefore, the degradation and mineralization of photocatalytic toluene are improved with great stability and humidity adaptability. This concept of promoting ring-opening with delocalized electrons provides a new strategy for the development of high-performance photocatalyst. [ABSTRACT FROM AUTHOR]

Room temperature catalytic oxidation (RTCO) using non-noble metals has emerged as a highly promising technique for removal of formaldehyde (HCHO) under ambient conditions; however, non-noble catalysts still face the challenges related to poor water resistance and low stability under harsh conditions. In this study, we synthesized a series of layered double hydroxides (LDHs) incorporating various dual metals (MgAl, ZnAl, NiAl, NiFe, and NiTi) for formaldehyde oxidation at ambient temperature. Among the synthesized catalysts, the NiTi-LDH catalyst showed an HCHO removal efficiency and CO 2 yield close to 100.0%, and exceptional water resistance and chemical stability on running 1300 min. The abundant hydroxyl groups in LDHs directly bonded with HCHO, leading to the production of CO 2 and H 2 O, thus inhibiting the formation of CO, even in the absence of O 2 and H 2 O. The coexistence of O 2 effectively reduced the reaction barrier for H 2 O molecule dissociation, facilitating the formation of hydroxyl groups and their subsequent backfill on the catalyst surface. The mechanisms underlying the involvement and regeneration of hydroxyl groups in room temperature oxidation of formaldehyde were elucidated with the combined in situ DRIFTS, HCHO-TPD-MS, and DFT calculations. This work not only demonstrates the potential of LDH catalysts in environmental applications but also advances the understanding of the fundamental processes involved in room temperature oxidation of formaldehyde.

The excessive production of nitrogen oxides (NO x ) from energy production, agricultural activities, transportation, and other human activities remains a pressing issue in atmospheric environment management. NO x serves both as a significant pollutant and a potential feedstock for energy carriers. Photocatalytic technology for NO x removal and recovery has received widespread attention and has experienced rapid development in recent years owing to its environmental friendliness, mild reaction conditions, and high efficiency. This review systematically summarizes the recent advances in photocatalytic removal, encompassing NO x oxidation removal (including single and synergistic removal and NO 3 - decomposition), NO x reduction to N 2 , and the emergent NO x upcycling into green ammonia. Special focus is given to the molecular understanding of the interfacial nitrogen-associated reaction mechanisms and their regulation pathways. Finally, the status and the challenges of photocatalytic NO x removal and recovery are critically discussed and future outlooks are proposed for their potential practical application., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Cancer metastasis is a major cause of mortality from several tumors, including those of the breast, prostate, and the thyroid gland. Since bone tissue is one of the most common sites of metastasis, the treatment of bone metastases is crucial for the cure of cancer. Hence, disease models must be developed to understand the process of bone metastasis in order to devise therapies for it. Several translational models of different bone metastatic tumors have been developed, including animal models, cell line injection models, bone implant models, and patient-derived xenograft models. However, a compendium on different bone metastatic cancers is currently not available. Here, we have compiled several animal models derived from current experiments on bone metastasis, mostly involving breast and prostate cancer, to improve the development of preclinical models and promote the treatment of bone metastasis., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Yu, Li, Peng, Wu, Chen, Shao and Zhang.)

Although various single-atom catalysts have been designed, atomically engineering their coordination environment remains a great challenge. Herein, a one-pot template-sacrificing pyrolysis approach is developed to synthesize well-defined Ni-N 4 -O catalytic sites on highly porous graphitic carbon for electrocatalytic CO 2 reduction to CO with high Faradaic efficiency (maximum of 97.2%) in a wide potential window (-0.56 to -1.06 V vs RHE) and with high stability. In-depth experimental and theoretical studies reveal that the axial Ni-O coordination introduces asymmetry to the catalytic center, leading to lower Gibbs free energy for the rate-limiting step, strengthened binding with *COOH, and a weaker association with *CO. The present results demonstrate the successful atomic-level coordination environment engineering of high-surface-area porous graphitic carbon-supported Ni single-atom catalysts (SACs), and the demonstrated method can be applied to synthesize an array of SACs (metal-N 4 -O) for various catalysis applications.

Cu 2 O microparticles with controllable crystal planes and relatively high stability have been recognized as a good platform to understand the mechanism of the electrocatalytic CO 2 reduction reaction (CO 2 RR). Herein, we demonstrate that the in situ generated Cu 2 O/Cu interface plays a key role in determining the selectivity of methane formation, rather than the initial crystal plane of the reconstructed Cu 2 O microparticles. Experimental results indicate that the methane evolution is dominated on all three different crystal planes with similar Tafel slopes and long-term stabilities. Density functional theory (DFT) calculations further reveal that *CO is protonated via a similar bridge configuration at the Cu 2 O/Cu interface, regardless of the initial crystal planes of Cu 2 O. The Gibbs free energy changes (ΔG) of *CHO on different reconstructed Cu 2 O planes are close and more negative than that of *OCCOH, indicating the methane formation is more favorable than ethylene on all Cu 2 O crystal planes., (© 2021 Wiley-VCH GmbH.)