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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]

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]

Nitric oxide, ammonia and volatile organic compounds are common air pollutants which need to be removed for health security. To reach ultra-low emission standards, photocatalysis has emerged as a environmentally benign and efficient method to lower pollutant levels. Understanding the pollutant removal mechanism is necessary to optimize the design of the photocatalyst. Here, we review air purification by gas–solid photooxidation. We discuss the role of light absorption, charge carrier separation and active sites for designing the photocatalyst. We present reaction processes with emphasis on the adsorption and activation of reactants, the formation of intermediates and byproducts, and the conversion pathways towards the final product. Perspectives of photocatalytic degradation in suppressing by-products, inhibiting deactivation and dealing with pollutant mixtures are discussed. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is a degenerative illness that greatly impacts the life quality of patients. Currently, the therapeutic approaches for OA are very limited in clinical. The extracellular vesicles (EVs) derived from different mesenchymal stem cells displayed a prominent therapeutic effect on OA. But most EVs have limited resources and the risks of host rejection, immunological response, and etc. Human umbilical cord mesenchymal stem cells (hUCMSCs) hold the advantages of easy availability, minimal immune rejection, and excellent immunomodulatory effects, although hUCMSCs-EVs have seldom been applied in OA. Herein, we investigated the potential immunomodulatory and anti-inflammatory effects of hUCMSCs-EVs on the treatment of OA. In our results, the treatment of hUCMSCs-EVs promoted the polarization of M2-type macrophages and the expression of anti-inflammation-related cytokines (IL-10). Notably, the supernate of M2 macrophages induced by hUCMSCs-EVs inhibited the level of inflammation-associated factors in OA chondrocytes caused by IL-1β. Further, injection of hUCMSCs-EVs in the articular lumen ameliorated progression of OA and exerted chondroprotective potential based on the OA joint model created by the surgical transection of the anterior cruciate ligament (ACLT). In addition, we found five highly enriched miRNAs in hUCMSCs-EVs, including has-miR-122-5p, has-miR-148a-3p, has-miR-486-5p, has-miR-let-7a-5p, and has-miR-100-5p by High-throughput sequencing of miRNAs, with targeted genes mainly enriched in the PI3K-Akt signaling pathway. Furthermore, we also detected the protein abundance of hUCMSCs-EVs using liquidation chromatography with tandem quadrupole mass spectrometry (LC–MS/MS) analysis. Thus, our study indicates that hUCMSCs-EVs can alleviate cartilage degradation during the OA progression, mechanically may through delivering key proteins and modulating the PI3K-Akt signaling pathway mediated by miRNAs to promote polarization of M2 macrophage, exhibiting potent immunomodulatory potential. The current findings suggest that hUCMSCs-EVs might serve as a new reagent for the therapy of OA. [ABSTRACT FROM AUTHOR]

Co-existing air pollutants, especially NO x and VOCs, will generate secondary photochemical pollution under light irradiation. However, simultaneous elimination of multi-pollutants has long been a challenge. Photocatalysis could turn the reaction pathway between pollutants to convert them into harmless products, which is a promising technology for multi-pollutant control. Here we achieved synergistic photocatalytic degradation of NO and C 7 H 8 on InOOH photocatalyst, and the performance can be adjusted by H 2 O through affecting the interaction between surface species and catalyst. In situ DRIFTS and GC-MS revealed that the improved efficiency originated from the fast conversion of C–N coupling intermediates led by additional H 2 O. Surface characterizations and DFT simulation determined that accumulated nitrates will compete with the adsorption of NO and C 7 H 8 , resulting in a decline in efficiency in the later stage. Although improved efficiency would bring more nitrates, as H 2 O has comparable adsorption to nitrate at the same site, high humidity can mitigate the deactivation. The photocatalyst can be also simply regenerated by water washing. This work reveals the complex interaction in the multi-pollutant system and provides guidelines for precisely regulating the synergistic removal of NO x and VOCs. [Display omitted] • Synergistic removal of NO x and C 7 H 8 are achieved on InOOH. • H 2 O has a promotion effect on the simultaneous degradation of NO and C 7 H 8. • The enhanced removal originated from the fast conversion of C–N species. • The nitrate would compete with NO and C 7 H 8 adsorption and is the deactivation factor. • H 2 O has comparable adsorption to nitrate at the same site, thus can mitigate the decline in efficiency. [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]

NO x and VOCs are primary air pollutants and their photochemical reactions would generate secondary pollutants like O 3 with NO 2 intermediate as the direct precursor. Here we apply a highly efficient In(OH) 3 photocatalyst to degrade mixed NO and C 7 H 8 for inhibition of photochemical O 3 generation. The dual pollutants show synergistic interaction from the adsorption process to photocatalytic reaction. C 7 H 8 and NO exhibit non-competitive adsorption and coupling reaction effects on In(OH) 3 surface. The coupling intermediate C 7 H 7 NOH would be oxidized to nitrotoluene and further decomposed into CO 2 and nitrates. Meanwhile, the protons and electrons released during the oxidation of C 7 H 8 can reduce NO to NH 4 +. Gibbs free energy calculation reveals that the coupling and reduction reactions are more favorable than the oxidation of NO to NO 2. The new conversion path of NO on In(OH) 3 when C 7 H 8 coexists could enable an increase of NO conversion efficiency to 100.0% and a decrease of NO 2 selectivity to only 3.7%, thus highly inhibiting the formation of O 3. [Display omitted] [ABSTRACT FROM AUTHOR]

Aromatic hydrocarbon is a representative type of VOCs, which causes adverse effects to human health. The degradation stability of aromatic hydrocarbon is of vital importance to commercializing a photocatalyst for its practical application. The most commonly used titanium dioxide photocatalyst (P25) was deactivated rapidly in the photocatalytic VOCs degradation process. In this work, the indium hydroxide (In(OH) 3) photocatalyst was developed, which exhibited not only higher efficient activity but also ultra-stable stability for degradation of benzene, toluene and their mixtures. The origin of the activity difference between two catalysts was investigated by combined experimental and theoretical ways. Based on in situ DRIFTS and GC-MS, it was revealed that benzoic acid and carbonaceous byproducts were specifically formed and accumulated on P25, which were responsible for deactivation of photocatalyst. In contrast, as revealed by both DFT calculations and experimental results, the reaction pathway with byproducts blocking the active sites can be thermodynamically avoided on In(OH) 3. This rendered high durability to In(OH) 3 photocatalyst in degradations of aromatic pollutants. The elucidation of deactivation-resistant effect and reaction mechanism as an ideal photocatalyst for practical usage were provided. [Display omitted] • Durable photocatalytic decomposition of VOCs was achieved on In(OH) 3. • The benzoic acid and carbonaceous byproducts were accumulated on P25. • The reaction pathway with byproducts can be avoided on In(OH) 3. • The reaction mechanisms of photocatalytic decomposition of VOCs was proposed. • The elucidation of deactivation-resistant mechanism on In(OH) 3 were proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Photocatalytic degradation of toluene was promoted by oxygen vacancy on InOOH. • OVs also facilitated methyl oxidation with the enhanced selectivity for ring opening. • In situ DRIFTS dynamically tracked the formation of primary reaction intermediates. • The reaction mechanism involved in photocatalysis of toluene is elucidated. The potential of oxygen vacancies (OVs) has been demonstrated in controlling photocatalytic activities by altering the electronic and/or band structures of photocatalysts. The effects of oxygen vacancies on photocatalytic reaction processes are yet unclear. In this work, indium oxyhydroxide (InOOH), well known as a wide band p-block metal compound with OVs, was synthesized through a one-pot solvothermal method to explore the roles of OVs in photocatalytic oxidation and ring opening of toluene. The defect level introduced by OVs enhanced light absorption and charge carrier separation, while promoting the activation of reactants to generate active oxygen species. As such, the modified InOOH was validated to enhance the photocatalytic performance by lowering the reaction energy barrier of the key intermediates during toluene oxidation (relative to the pristine InOOH). More strikingly, the energy barrier for the formation of benzoic acid was reduced with the increasing number of OVs on InOOH (accompanied by the increases in the ring opening reaction rates), in line with the results derived from the in situ DRIFTS investigation and theoretical calculation. Accordingly, it is possible to explain the mechanism regulating the photocatalytic oxidation of toluene on defective InOOH. This work could provide an electronic insight into oxygen vacancy engineering as a new strategy to enhance the photocatalytic selectivity and activity for VOC degradation. [ABSTRACT FROM AUTHOR]

[Display omitted] Developing electrocatalysts for efficient reduction of nitrate contaminant to value-added ammonia as energy carrier is a pivotal part for restoring the nitrogen cycle. However, the selectivity of ammonia is far from satisfaction, often suffering from accumulation of toxic nitrite byproduct. Herein, a series of CuNi alloy nanoparticles embedded in nitrogen-doped carbon matrix (CuNi/NC) with hierarchical pores were fabricated by pyrolysis of bimetallic metal–organic frameworks (MOFs). The catalysts exhibited excellent selectivity (94.4%) and faradaic efficiency (79.6%) for nitrate reduction to ammonia, greatly outperforming the performance of monometallic Cu/NC (selectivity of 60.8% and faradaic efficiency of 60.6%). Impressively, the introduction of nickel distinctly suppressed the production of toxic byproduct of nitrite. Online differential electrochemical mass spectrometry (DEMS) and in situ surface-enhanced infrared absorption spectroscopy (SEIRAS) tests were utilized to reveal the key intermediates and the reaction pathway. Density functional theory (DFT) calculations demonstrated that the introducing of nickel into copper lattice modified both the electronic and geometric structures of the catalysts. The copper and nickel sites in the CuNi alloy catalysts operate synergistically to facilitate the hydrogenation of NO 2 * to HNO 2 * and suppress the hydrogen evolution reaction, boosting the selective formation of ammonia. This work could provide a new synthetic route for bimetallic catalysts and mechanistic understanding for nitrate to ammonia reaction. [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]

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]

• A highly active and selective Pd particles/C3N4 is designed by DFT. • The Pd particles/C3N4 is fabricated with an extremely low content of Pd particles. • The Pd particles/C3N4 could effectively suppress the toxic intermediate NO2. • The electronic structure of Pd particles/C3N4 is tuned for · OH production. • The reaction mechanism of photocatalytic NO removal is revealed. Rational design of highly active and selective photocatalyst for NO removal is significant for the commercial application of photocatalytic technology because the secondary byproduct caused by insufficient and non-selective pollutant oxidation process is a major challenge. In this work, Pd nanoparticles decorated C 3 N 4 (PdCN) is designed by density functional theory (DFT) at first. The PdCN exhibits superiority to CN in terms of both kinetics and thermodynamics performances, as reflected in the lower activation barrier of rate-determining step and higher selectivity for the final product (nitrate) instead of toxic intermediate (NO 2). The as-designed highly selective and efficient photocatalyst is then fabricated by a facile method with an extremely low content of Pd particles supported on C 3 N 4. Compared to bare CN, the synthesized PdCN exhibits highly enhanced purification of NO in air and strong inhibition of toxic NO 2 by-product as supported by in-situ DRIFTS investigation, which is consistent with the theoretical prediction. This work is a typical demonstration of setting up a bridge between theory and experiment to give a promising way to the rational design of advanced photocatalysts and atomic understanding of the reaction mechanism. [ABSTRACT FROM AUTHOR]

• Monodisperse Au nanoparticles@g-C 3 N 4 has been designed and fabricated. • The Au@CN exhibits higher photocatalytic NO removal efficiency. • The Au@CN could effectively suppress the toxic intermediate NO 2. • The reaction pathway of photocatalytic NO oxidation can be tuned. • Ideal electronic structure of Au@CN enables direct conversion of NO to nitrate. Oxidation of low-concentration nitrogen oxides (NO x) to nitrate with solar energy is an efficient way to remove them from atmospheric environment under semi-enclosed or ill-airflow conditions. However, conventional photocatalysts applied in NO x removal face the challenges of low efficiency and generation of toxic byproducts (nitrogen dioxide, NO 2) leading to secondary pollution. To tackle these issues, monodisperse gold nanoparticles supported on graphitic carbon nitride (Au@CN) was designed and fabricated by a facile method. The Au@CN exhibited a highly enhanced nitric oxide (NO) oxidation activity and superior NO 2 inhibition ability. The microstructures, optical properties and electronic structure of the photocatalysts were analyzed with advanced tools. The in situ diffuse reflectance infrared spectroscopy (DRIFTS) was applied to dynamically monitor and reveal the reaction process at time sequence. Density functional theory (DFT) and electron spin resonance (ESR) were combined to explore the oxidation mechanism at molecular level. It was found that (1) the presence of Au metal site favored the adsorption and activation of the gas molecules; (2) the high separation efficiency of the photogenerated electron-hole pairs enhanced the production of radicals for NO oxidation; (3) the unique electronic structure of Au@CN prefers nitrate formation with a low rate-determining barrier and largely suppress the toxic intermediate NO 2 , thus effectively controlling the secondary pollution. The present work could provide a novel mechanistic insight into visible-light photocatalytic NO oxidation and selectivity on Au@CN which is beneficial for designing efficient and safe photocatalyst with low environmental risk. [ABSTRACT FROM AUTHOR]

[Display omitted] Improving the selectivity of photocatalysis and reducing the generation of toxic by-products are the two key challenges for the development of highly efficient and stable photocatalysts. In this work, it was revealed that Zn-Ti-layered double hydroxide (ZT-LDH) photocatalyst, which generated less intermediates, showed better toluene degradation efficiency (removal ratio, 75.2%) and stability, compared with P25 (removal ratio, 10.9%). During the photocatalytic toluene degradation, benzaldehyde and benzoic acid were the main intermediates existed in the gas phase and on the surface of the catalyst, respectively. By combining experiments with theoretical calculation, it was found that the hydrogen atoms on the hydroxyl groups in the LDH would selectively attract the oxygen atoms in the carbon–oxygen double bond of the two major intermediates, facilitating their adsorption and activation on ZT-LDH. Besides, the surface electronic structure of ZT-LDH was demonstrated to facilitate the ring-opening reaction of the two major intermediates, eventually maintaining high activity and stability. This work could provide new molecular perspectives for understanding the photocatalytic reactions in VOCs degradation and developing efficient and stable photocatalysts. [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]

[Display omitted] Circular RNAs (circRNAs), a subclass of noncoding RNAs, have been demonstrated to play an essential role in osteosarcoma (OS) development. However, there is still a significant gap in investigating its biological functions and underlying molecular mechanisms, and novel targets of circRNAs have yet to be fully explored. Herein, we found that hsa_circ_0007031 is noticeably raised in OS clinical tissues and cell lines. Hsa_circ_0007031 accelerates OS cell proliferation and migration in vitro and tumor growth and metastasis in vivo and is strongly linked with the stemness of cancer stem cells in OS. Mechanistically, hsa_circ_0007031 shares miRNA response elements with Homeobox B6 (HOXB6), which is identified as a novel pro-tumorigenic gene of OS. Hsa_circ_0007031 competitively binds to miR-196a-5p to prevent miR-196a-5p from lowering the level of HOXB6, which modulates chemokines of cytokine-cytokine receptor interaction signaling pathway and finally promotes OS malignant behavior. In summary, our data unveiled that hsa_circ_0007031/miR-196a-5p/HOXB6 axis-mediated cytokine-cytokine receptor interaction facilitates the progression of OS and maintains the properties of tumor stem cells, which could be a promising therapeutic target for OS. [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]

• Innovative tumor drug-resistant mechanistic research. • Innovative multifunctional bionic nanomaterial design. • Good biosafety, circulatory system stability, and tumor targeting ability. • Drug/Fenton-like reaction/low-temperature photothermal combined tumor killing. • Improvement of the immune microenvironment in chemo-resistant tumor. Given that the treatment of drug-resistant osteosarcoma is a significant clinical challenge, in drug-resistant tumors, the role of endothelial cells has been recently emphasized. We noted that heterogeneous vascular endothelial cells (ONHVECs) in drug-resistant osteosarcoma tissues may inhibit macrophage-mediated killing of tumor cells, thus promoting the occurrence of drug resistance. Accordingly, we designed a type of hybrid membrane-coated multifunctional nanoparticle (NP), SiO 2 @PDA/Fe3+@Cis@HM. The NPs had good biocompatibility and enhanced the occurrence of low-temperature photothermal Fenton-like reactions. The hybrid membrane endowed the NPs with a tumor homing ability and homologous cell targeting ability, thus simultaneously targeting drug-resistant tumor cells and ONHVECs, in addition to killing tumor cells via efficient delivery of cisplatin and ROS produced by accelerated Fenton-like reactions. Through in vivo and in vitro experiments, we confirmed that SiO 2 @PDA/Fe3+@Cis@HM NPs efficiently killed tumor cells as well as ONHVECs. The endogenous exosomes produced by damaged ONHVECs induced anti-tumor M1 macrophage polarization to indirectly kill tumor cells and achieve synergistic therapy. This immune regulation was completely inherent and exhibited consistent efficacy, without ethical connotations. In conclusion, this multifunctional treatment strategy is the first to adopt a tumor cell/vascular endothelial cell double-targeted concept, which realized the direct killing of drug-resistant tumor cells and a natural immune enhancement response and could become a new paradigm for the treatment of drug-resistant osteosarcoma. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new strategy of B doping in Bi 2 O 2 CO 3 (B-BOC) was developed. • The B doping leads to the formation of intermediate levels and electronic channels. • The photocatalytic elimination of NO in air was promoted via B doping. • The electron localization induced by B doping can directly activate O 2 and NO molecules. • The combined in-situ FRIFT and DFT reveals mechanism of photocatalytic NO oxidation. Challenges are remaining in preparation of photocatalysts with efficient separation of charge carriers and utilization of visible light, and understanding of the reaction mechanism. In this work, B-doped Bi 2 O 2 CO 3 hierarchical microspheres were prepared by one-step hydrothermal treatment using bismuth citrate and sodium tetraborate as precursors. Compared with pure Bi 2 O 2 CO 3 , the B-doped Bi 2 O 2 CO 3 exhibited high visible-light photocatalytic activity of removing NO to achieve efficient air purification. Combined with experiments and DFT calculations, the doped-B could induce the formation of the intermediate level near the valence band, thus increasing the visible light absorption. The B-doping could also promote the separation of electron-hole pairs and enhance the activation of reactants. Therefore, plentiful reactive could be generated and detected by ESR via the reaction between the activated small reactant molecules and separated photogenerated carriers. To reveal the reaction mechanism of photocatalytic NO oxidation, the in-situ DRIFTS method was used to study the reaction processes, and an important intermediate NO 2 + was found. The presence of NO 2 + participated in the reaction enabled favorable formation for the final product of nitrates. This work could provide a new strategy for the improvement of photocatalytic efficiency. [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]

A facile and efficient strategy via a cross-linking reaction with organic linkers was proposed to design and synthesize novel isotypic heterojunctions (CN-T/CN-M) based on graphitic carbon nitride (CN) derived from different monomers, which shows superior photocatalytic activity and high stability. • A strategy based on cross-linking reaction was proposed for fabrication of CN-T/CN-M isotypic heterojunction. • The as-prepared CN-T/CN-M shows superior photocatalytic performance of hydrogen evolution. • The role of as-formed amide covalent bonds in CN-T/CN-M was well investigated. • CN-T/CN-M exhibits high stability and reusability during the catalytic reaction. • A mechanism for enhanced photocatalytic hydrogen evolution over CN-T/CN-M was proposed. Herein, a facile and efficient strategy was proposed to design and synthesize novel isotypic heterojunctions (CN-T/CN-M) based on graphitic carbon nitride (CN) derived from different monomers via cross-linking reaction with organic linkers. DFT calculations and transient spectra analyses elucidated that integration of single CN layers via chemical amide condensation can not only reduce the defective -NH 2 groups that act as charge recombination sites but also extend the large delocalized π-electron systems, leading to a suitable internal electric field to efficiently promote migration of photogenerated carriers. Consequently, compared with the individual CN components and their heterostructure prepared by conventional method, CN-T/CN-M shows superior photocatalytic activity of H 2 evolution and higher stability under visible light irradiation. Furthermore, an enhanced photocatalytic mechanism was proposed. This work develops a new avenue via covalent cross-linking reaction to construct efficient and stable heterostructured catalysts and provides new idea to design isotypic heterojunction with excellent photocatalytic performance. [ABSTRACT FROM AUTHOR]

A well-defined In 2 O 3 /InN heterojunction was developed for the electrocatalytic CO 2 reduction reaction to formate. The O-N interaction at the interface of In 2 O 3 /InN heterojunction promotes the charge transfer to activate CO 2 molecules, lower the Gibbs free energy for *HCOO formation and thus results in unprecedented high Faradaic efficiency (95.7% at −1.48 V vs. RHE) and outstanding stability. [Display omitted] • Pure In 2 O 3 or In 2 O 3 /InN heterostructure were obtained under different atmosphere. • The In 2 O 3 /InN catalyst exhibits enhanced FE formate (>95%) from −1.37 to −1.59 V. • The In 2 O 3 /InN heterojunction exhibits almost no degradation of performance after 30 h. • The O-N interaction at the interface of In 2 O 3 /InN heterojunction promotes charge transfer. • In situ ATR-SEIRAS and DFT were performed to reveal the electrocatalytic mechanism. Electrocatalytic reduction of CO 2 into value-added chemicals and fuels is of intensive urgence and importance to relieve the growing CO 2 emission and achieve the carbon neutrality. Herein, an In 2 O 3 /InN heterojunction was constructed and firstly utilized in electrocatalytic CO 2 reduction reaction (CO 2 RR) to formate with high Faradaic efficiency (95.7% at −1.48 V vs. RHE) and outstanding stability. The in-depth experimental analyses together with theoretical studies reveal that the O-N interaction at the interface between In 2 O 3 and InN could provide a charge transfer channel and lead to electron enrichment on the surface of InN, promoting the activation of CO 2 molecules, lowering the Gibbs free energy for the formation of *HCOO intermediate and strengthening the binding with *HCOO during CO 2 RR. This work provides a fundamental understanding of the interaction at In-based heterostructure interface for highly selective CO 2 reduction to formate and offers a universal route for the design of other type metal oxide/nitride heterostructures for various catalytic applications. [ABSTRACT FROM AUTHOR]

• The activation energies are ascertained for ROS generation and transformation. • The facet engineering of BiOCl photocatalyst benefits the NO x removal efficiency. • The generation of intermediate NO 2 is significantly suppressed. • Experimental and theoretical methods are combined to reveal the reaction mechanism. The generation and transformation of reactive oxygen species (ROS) is a key parameter in catalyzing photocatalytic gas-phase oxidation reactions for environmental remediation. Thus the determination, quantification and kinetic tracking of ROS are conclusively required to realize complete pollutant conversion and intermediates suppression. By quantifying the activation energies (E a) and ascertaining the rate-determining step (RDS), a panoramic understanding is established in ROS-induced NO x oxidation reactions. To be specific, the BiOCl photocatalyst with tailored facets were designed and fabricated as model catalysts. It is proposed that the ROS generation and transformation pathways are along the path of OH → H 2 O 2 → O 2 −, in which the H 2 O 2 dissociation is the RDS for O 2 − generation. Moreover, it is concluded that NO 2 is the primary intermediate in NO oxidation reaction, and the further transformation of NO 2 requires the highest E a among all the elementary reactions. Significantly decreased E a and suppressed NO 2 accumulation are realized on the {0 1 0} facet of BiOCl to achieve efficient NO x conversion. A new perspective is stated in this research to establish a comprehensive understanding between ROS generation mechanism and intermediates suppression for efficient NO x removal, which provides new insights into the application of photocatalysis technology for air pollution control area. [ABSTRACT FROM AUTHOR]