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Efficient molecular oxygen activation is crucial for catalytic oxidation reaction, but highly depends on the construction of active sites. In this study, we demonstrate that dual adjacent Fe atoms anchored on MnO 2 can assemble into a diatomic site, also called as MnO 2 -hosted Fe dimer, which activates molecular oxygen to form an active intermediate species Fe(O = O)Fe for highly efficient CO oxidation. These adjacent single-atom Fe sites exhibit a stronger O 2 activation performance than the conventional surface oxygen vacancy activation sites. This work sheds light on molecular oxygen activation mechanisms of transition metal oxides and provides an efficient pathway to activate molecular oxygen by constructing new active sites through single atom technology. Efficient oxygen activation is crucial for catalytic oxidation reaction, but highly depends on the construction of active sites. Here, dual adjacent Fe atoms anchored on MnO 2 can assemble into a diatomic site, which activates molecular oxygen to form an active intermediate species Fe(O = O)Fe for CO oxidation.

Surface high-valent iron-oxo species (≡Fe IV =O) are reliable and green oxygen atom transfer reagents, but the ability is seriously inhibited by the maximal orbital overlap of axial Fe = O double bond in a symmetric planar coordination environment. Herein, we report the synthesis of planar asymmetric surface Fe IV  = O (PA-≡Fe IV  = O) on pyrite using chlorite as the oxidant, where the in-situ generated ClO 2 can transform a planar Fe-S bond to Fe-Cl by oxidizing and subsequently substituting planar sulfur atoms. Different from planar symmetric surface Fe IV  = O (PS-≡Fe IV  = O) with electron localization around axial Fe = O, PA-≡Fe IV  = O delocalizes electrons among Fe, axial oxo moiety and its planar ligands owing to the stronger electron-withdrawing capacity of Cl, which effectively weakens the orbital overlap of axial Fe = O bonding and thus facilitates the rapid electron transfer from the substrates to the unoccupied antibonding orbital of PA-≡Fe IV  = O, realizing more efficient oxygen atom transfer oxidation of methane, methyl phenyl sulfide, triphenylphosphonate and styrene than PS-≡Fe IV  = O. This study offers a facile approach for the synthesis of planar asymmetric surface Fe IV  = O, and also underscores the importance of planar coordination environment of high-valent metal-oxo species in the oxygen atom transfer reactions. Surface high-valent iron-oxo species (≡Fe⁴⁺=O) are effective and environmentally friendly reagents for oxygen atom transfer. Here, the authors create a planar, asymmetric ≡Fe⁴⁺=O with a Fe–Cl₁S₃ structure using pyrite and chlorite, which enhances electron delocalization and weakens the Fe=O bond to improve reaction efficiency.

Nature-inspired high-spin Fe IV  = O generation enables efficient ambient methane oxidation. By engineering sulfur-bridged dual ≡Fe II …Fe II ≡ sites on pyrite (FeS 2 ) mimicking soluble methane monooxygenase, we achieve O 2 -driven formation of high-spin (S = 2) surface Fe IV  = O species at room temperature and pressure. Strategic removal of bridging S atoms creates active sites that facilitate O 2 activation via transient ≡Fe-O-O-Fe≡ intermediates, promoting homolytic O − O bond cleavage. The resulting Fe IV  = O exhibits an asymmetrically distorted coordination environment that reduces the crystal field splitting and favors the occupation of higher energy d-orbitals with unpaired electrons. Impressively, this configuration can efficiently convert CH 4 to CH 3 OH through an oxygen transfer reaction with a synthetic efficiency of TOF = 27.4 h −1 and selectivity of 87.0%, outperforming most ambient O 2 -driven benchmarks under comparable conditions and even surpassing many H 2 O 2 -mediated systems. This study offers a facile method to synthesize high-spin surface Fe IV  = O and highlights the importance of metal spin state tailoring on non-enzymatic methane activation. High-spin Fe(IV) = O sites efficiently activate methane but are challenging to synthesize. This study develops dual Fe(II) sites on FeS 2 , generating high-spin Fe(IV) = O from O 2 , achieving superior methane-to-methanol conversion under mild conditions.

Ternary chalcogenide semiconductor, cadmium indium sulfide (CdIn 2 S 4 ), was prepared by a simple solvothermal method using ethylene glycol as a solvent, as well as indium chloride tetrahydrate (InCl 3 . 4H 2 O), cadmium nitrate tetrahydrate [Cd(NO 3 ) 2 . 4H 2 O], and thiacetamide (TAA) as precursors. The resulted sample was subject to a series of characterizations. It is the first time to use CdIn 2 S 4 sample as a visible light-driven photocatalyst for simultaneous selective redox transformation of organic aromatic compounds. The results indicate that the as-synthesized CdIn 2 S 4 photocatalyst not only has excellent photocatalytic performance compared with pure In 2 S 3 and CdS for the selective oxidation of aromatic alcohols in an oxygen environment, but also shows high photocatalytic redox activities under nitrogen atmosphere. A possible mechanism for the photocatalytic redox reaction in the coupled system was proposed. It is hoped that our current work could extend the applications of CdIn 2 S 4 photocatalyst and provide new insights for selective transformations of organic compounds.

Nature-inspired high-spin Fe  = O generation enables efficient ambient methane oxidation. By engineering sulfur-bridged dual ≡Fe …Fe ≡ sites on pyrite (FeS ) mimicking soluble methane monooxygenase, we achieve O -driven formation of high-spin (S = 2) surface Fe  = O species at room temperature and pressure. Strategic removal of bridging S atoms creates active sites that facilitate O activation via transient ≡Fe-O-O-Fe≡ intermediates, promoting homolytic O - O bond cleavage. The resulting Fe  = O exhibits an asymmetrically distorted coordination environment that reduces the crystal field splitting and favors the occupation of higher energy d-orbitals with unpaired electrons. Impressively, this configuration can efficiently convert CH to CH OH through an oxygen transfer reaction with a synthetic efficiency of TOF = 27.4 h and selectivity of 87.0%, outperforming most ambient O -driven benchmarks under comparable conditions and even surpassing many H O -mediated systems. This study offers a facile method to synthesize high-spin surface Fe  = O and highlights the importance of metal spin state tailoring on non-enzymatic methane activation.

Surface high-valent iron-oxo species (≡Fe =O) are reliable and green oxygen atom transfer reagents, but the ability is seriously inhibited by the maximal orbital overlap of axial Fe = O double bond in a symmetric planar coordination environment. Herein, we report the synthesis of planar asymmetric surface Fe  = O (PA-≡Fe  = O) on pyrite using chlorite as the oxidant, where the in-situ generated ClO can transform a planar Fe-S bond to Fe-Cl by oxidizing and subsequently substituting planar sulfur atoms. Different from planar symmetric surface Fe  = O (PS-≡Fe  = O) with electron localization around axial Fe = O, PA-≡Fe  = O delocalizes electrons among Fe, axial oxo moiety and its planar ligands owing to the stronger electron-withdrawing capacity of Cl, which effectively weakens the orbital overlap of axial Fe = O bonding and thus facilitates the rapid electron transfer from the substrates to the unoccupied antibonding orbital of PA-≡Fe  = O, realizing more efficient oxygen atom transfer oxidation of methane, methyl phenyl sulfide, triphenylphosphonate and styrene than PS-≡Fe  = O. This study offers a facile approach for the synthesis of planar asymmetric surface Fe  = O, and also underscores the importance of planar coordination environment of high-valent metal-oxo species in the oxygen atom transfer reactions.

Ternary chalcogenide semiconductor, cadmium indium sulfide (CdIn S ), was prepared by a simple solvothermal method using ethylene glycol as a solvent, as well as indium chloride tetrahydrate (InCl 4H O), cadmium nitrate tetrahydrate [Cd(NO ) 4H O], and thiacetamide (TAA) as precursors. The resulted sample was subject to a series of characterizations. It is the first time to use CdIn S sample as a visible light-driven photocatalyst for simultaneous selective redox transformation of organic aromatic compounds. The results indicate that the as-synthesized CdIn S photocatalyst not only has excellent photocatalytic performance compared with pure In S and CdS for the selective oxidation of aromatic alcohols in an oxygen environment, but also shows high photocatalytic redox activities under nitrogen atmosphere. A possible mechanism for the photocatalytic redox reaction in the coupled system was proposed. It is hoped that our current work could extend the applications of CdIn S photocatalyst and provide new insights for selective transformations of organic compounds.

Endometriosis (EMs) is one of the most frequent diseases of reproductive-age women and is characterized by the growth of endometrial tissues beyond the uterus. The enhanced proliferative and migratory potential of endometrial stromal cells (ESCs) plays an important role in the progression of EMs. Mounting studies have demonstrated that long noncoding RNAs (lncRNAs) exert an important role in regulating the development and progression of EMs. Given the aberrant expression of lncRNA ADAMTS9-AS1 in ectopic endometrium (ecEM), we investigated the biological effect of ADAMTS9-AS1 on ESC proliferation and migration and explored the underlying mechanism. The current data showed that ADAMTS9-AS1 expression was significantly upregulated in ecEM compared with eutopic endometrium (euEM) in patients with EMs and in a murine model of EMs. Functionally, ADAMTS9-AS1 knockdown in ectopic ESCs (EESCs) decreased cell viability and migration, whereas ADAMTS9-AS1 overexpression in normal ESCs (NESCs) enhanced cell viability and migration. More importantly, the effect of ADAMTS9-AS1 inhibition on decreasing ESC viability was significantly blocked by ferrostatin-1 (Fer-1, a ferroptosis inhibitor), and ADAMTS9-AS1 overexpression repressed erastin (a ferroptosis activator)-induced cell death. Furthermore, the regulatory role of ADAMTS9-AS1 in ferroptosis was defined and evidenced by increased reactive oxygen species (ROS) levels and malonyl dialdehyde (MDA) content and decreased expression of glutathione peroxidase 4 (GPX4) after ADAMTS9-AS1 inhibition. Mechanistically, ADAMTS9-AS1 functioned as a competing endogenous RNA (ceRNA) by sponging miR-6516-5p to derepress the expression of GPX4, the critical repressor of ferroptosis. Taken together, these results demonstrate that upregulated ADAMTS9-AS1 accelerates ESC proliferation and migration by regulating miR-6516-5p/GPX4-dependent ferroptosis and may be a potential target for the treatment of EMs.

Circular RNAs (circRNAs), highly expressed in the central nervous system, are involved in various regulatory processes and implicated in some pathophysiology. However, the potential role of circRNAs in psychiatric diseases, particularly major depressive disorder (MDD), remains largely unknown. Here, we demonstrated that circular RNA DYM (circDYM) levels were significantly decreased both in the peripheral blood of patients with MDD and in the two depressive-like mouse models: the chronic unpredictable stress (CUS) and lipopolysaccharide (LPS) models. Restoration of circDYM expression significantly attenuated depressive-like behavior and inhibited microglial activation induced by CUS or LPS treatment. Further examination indicated that circDYM functions as an endogenous microRNA-9 (miR-9) sponge to inhibit miR-9 activity, which results in a downstream increase of target-HECT domain E3 ubiquitin protein ligase 1 (HECTD1) expression, an increase of HSP90 ubiquitination, and a consequent decrease of microglial activation. Taken together, the results of our study demonstrate the involvement of circDYM and its coupling mechanism in depression, providing translational evidence that circDYM may be a novel therapeutic target for depression.

Background The triglyceride-glucose (TyG) index is a predictor of cardiovascular diseases; however, to what extent the TyG index is associated with cardiovascular diseases through renal function is unclear. This study aimed to evaluate the complex association of the TyG index and renal function with cardiovascular diseases using a cohort design. Methods This study included participants from the China Health and Retirement Longitudinal Study (CHARLS) free of cardiovascular diseases at baseline. We performed adjusted regression analyses and mediation analyses using Cox models. The TyG index was calculated as Ln [fasting triglyceride (mg/dL) × fasting glucose (mg/dL)/2]. Renal function was defined by the estimated glomerular filtration rate (eGFR). Results A total of 6 496 participants were included in this study. The mean age of the participants was 59.6 ± 9.5 years, and 2996 (46.1%) were females. During a maximum follow-up of 7.0 years, 1 996 (30.7%) people developed cardiovascular diseases, including 1 541 (23.7%) cases of heart diseases and 651 (10.0%) cases of stroke. Both the TyG index and eGFR level were significantly associated with cardiovascular diseases. Compared with people with a lower TyG index (median level) and eGFR ≥ 60 ml/minute/1.73 m 2 , those with a higher TyG index and decreased eGFR had the highest risk of cardiovascular diseases (HR, 1.870; 95% CI 1.131–3.069). Decreased eGFR significantly mediated 29.6% of the associations between the TyG index and cardiovascular diseases. Conclusions The combination of a higher TyG index and lower eGFR level was associated with the highest risk of cardiovascular diseases. Renal function could mediate the association between the TyG index and cardiovascular risk.