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Osteoporosis, resulting from overactive osteoclasts and leading to elevated fracture risk, has emerged as a global public health concern due to the aging population. Therefore, inhibiting osteoclastogenesis and bone resorption function represents a crucial approach for preventing and treating osteoporosis. The purpose of this study was to examine the effects and molecular mechanisms of Butylphthalide (NBP) on the differentiation and function of osteoclasts induced by RANKL. Osteoclastogenesis was assessed through TRAP staining and bone slice assay. An animal model that underwent ovariectomy, simulating postmenopausal women’s physiological characteristics, was established to investigate the impact of Butylphthalide on ovariectomy-induced bone loss. To delve deeper into the specific mechanisms, we employed Western blot, PCR, immunofluorescence, and immunohistochemical staining to detect the expression of proteins that are associated with the osteoclast signaling pathway. In this study, we found that Butylphthalide not only suppressed osteoclastogenesis and bone resorption in vitro but also significantly decreased TRAcP-positive osteoclasts and prevented bone loss in vivo. Further mechanistic experiments revealed that Butylphthalide reduces intracellular ROS in osteoclasts, inhibits the MAPK and NFATc1 signaling pathways, and downregulates the key genes and proteins of osteoclasts. This inhibits osteoclast formation and function. The reduction in ROS in osteoclasts is intricately linked to the activity of Butylphthalide-modulated antioxidant enzymes. Overall, NBP may offer a alternative treatment option with fewer side effects for skeletal diseases such as osteoporosis.

The utilization of catalysts comprising metal nanoparticle has been beneficial for enhancing the performance of oxygen reduction reaction (ORR). However, the inadequate intrinsic activity of these catalysts still presents a significant challenge, limiting their overall effectiveness. This issue can be addressed by introducing single atoms, which can create a synergistic effect with the nanoparticles to catalyse and thereby improve performance. Nevertheless, the synergistic catalysis of nanoparticles and single atoms is still under investigation. In this study, we fabricated a core‐shell structured carbon framework incorporating Fe single atoms and Bi nanoparticles through the pyrolysis of COF and MOF core‐shell structures. Introducing Fe single atoms into ZIF‐8, with Fe‐ZIF‐8 as the core and Bi‐containing COF as the shell, resulted in higher ORR activity. The catalyst exhibited a half‐wave potential of 0.867 V and a high current density of 6.68 mA cm−2 in 0.1 M KOH, which were comparable to those of Pt/C equivalent. This study provides new research concepts for exploring the application of single atoms and nanoparticles in catalytic oxygen reduction reactions through synergistic effects. [ABSTRACT FROM AUTHOR]

The development of catalysts composed of single atoms is crucial for enhancing the performance of oxygen reduction reaction (ORR). However, the unsatisfactory intrinsic activity of these catalysts still poses a major challenge, limiting their overall effectiveness. One approach to addressing this challenge is the introduction of metal clusters, which can form a synergistic effect with the single atoms, ultimately improving their performance. In this study, core‐shell structured carbon polymer is constructed with Zn atoms and Sn nanoclusters by directly subjecting pyrolysis of the covalent organic polymer (COP) and metal organic framework (MOF) (COP@MOF). The thin COP shell serves a dual purpose: it prevents the collapse and aggregation of zeolitic imidazolate framework‐8 (ZIF‐8) and promotes the formation of mesopores, facilitating mass transport and enhancing the graphitization degree to improve conductivity. The resulting Sn‐COP@MOF800 exhibits promising catalytic performance in the ORR, demonstrating a half‐wave potential of 0.81 V and current density of 5.56 mA cm−2 in 0.1 m KOH, which is comparable to that of Pt/C. This study provides new ideas for exploring the application of metal single atoms and metal nanoclusters in ORR catalysis through synergistic effects. [ABSTRACT FROM AUTHOR]

Flame retarded and smoke suppressed vinyl ester resin (VER) were prepared through ammonium polyphosphate (APP) coupled with different smoke suppressants. The flame retardancy of these composites was tested by the limiting oxygen index and UL-94 tests. The typical combustion parameters including heat release rate (HRR), peak of HRR (p-HRR), total heat release, smoke production rate, and total smoke production were detected using a cone calorimeter. The smoke suppressants CaC[O.sub.3], ZnMo[O.sub.4], [Cu.sub.2]O, and [Fe.sub.2][O.sub.3] show different effect on flame retardancy and smoke suppression of VER composites when they are coupled with APP, the synergistic action of APP and CaC03 is more effective on decreasing the HRR and smoke release rate than several other smoke suppressants. This is attributed to the fact that CaC[O.sub.3] could promote the formation of a dense carbon layer with high thermal stability and anti-oxidation property, which could act as an effective physical barrier. The flame retardant performances and mechanisms of APP and CaC[O.sub.3] were evaluated and analyzed at length by thermogravimetric coupled with a Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, FTIR, and X-ray diffraction., INTRODUCTION Vinyl ester resin (VER) is an oligomer produced by the reaction between a bisphenol-A epoxy oligomer and an unsaturated carboxylic acid such as acrylic acid or methacrylic acid [l-5]. [...]

The ion extraction and electro/photo catalysis are promising methods to address environmental and energy issues. Covalent organic frameworks (COFs) are a class of promising template to construct absorbents and catalysts because of their stable frameworks, high surface areas, controllable pore environments, and well‐defined catalytic sites. Among them, ionic COFs as unique class of crystalline porous materials, with charges in the frameworks or along the pore walls, have shown different properties and resulting performance in these applications with those from charge‐neutral COFs. In this review, current research progress based on the ionic COFs for ion extraction and energy conversion, including cationic/anionic materials and electro/photo catalysis is reviewed in terms of the synthesis strategy, modification methods, mechanisms of adsorption and catalysis, as well as applications. Finally, we demonstrated the current challenges and future development of ionic COFs in design strategies and applications. [ABSTRACT FROM AUTHOR]

The catalytic performance for electrocatalytic CO2 reduction reaction (CO2RR) depends on the binding strength of the reactants and intermediates. Covalent organic frameworks (COFs) have been adopted to catalyze CO2RR, and their binding abilities are tuned via constructing donor‐acceptor (DA) systems. However, most DA COFs have single donor and acceptor units, which caused wide‐range but lacking accuracy in modulating the binding strength of intermediates. More elaborate regulation of the interactions with intermediates are necessary and challenge to construct high‐efficiency catalysts. Herein, the three‐component COF with D‐A‐A units was first constructed by introducing electron‐rich diarylamine unit, electron‐deficient benzothiazole and Co‐porphyrin units. Compared with two‐component COFs, the designed COF exhibit elevated electronic conductivity, enhanced reducibility, high efficiency charge transfer, further improving the electrocatalytic CO2RR performance with the faradic efficiency of 97.2 % at −0.8 V and high activity with the partial current density of 27.85 mA cm−2 at −1.0 V which exceed other two‐component COFs. Theoretical calculations demonstrate that catalytic sites in three‐component COF have suitable binding ability of the intermediates, which are benefit for formation of *COOH and desorption of *CO. This work offers valuable insights for the advancement of multi‐component COFs, enabling modulated charge transfer to improve the CO2RR activity. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) have been utilized as the ideal candidates to preciously construct electrocatalysts. However, the highly ordered degree of COFs renders the catalytic centers closely stacked, which limits the utilization efficiency of catalytic sites. Herein, we have first constructed dangling and staggered‐stacking aldehyde (–CHO) from [4 + 3] COFs as catalytic centers for 2e− oxygen reduction reaction (ORR). The new catalytic COFs have unreacted dangling ‐CHO out of the COFs' planes, which are more easily exposed in electrolytes than the sites in the frameworks. More importantly, these –CHO adopt staggered stacking models, and thus provide larger space for mass transport than those with eclipsed stacking models. In addition, by tuning the triratopic linkers in the COFs, the catalytic properties are well modulated. The optimized COF shows high selectivity and activity for 2e− ORR, with H2O2 selectivity of 91%, and mass activity of 12.2 A g−1, respectively. The theoretical calculation further reveals the higher activity for the pyridine‐contained B18C6‐PTTA‐COF due to the promoted binding ability of the intermediate OOH* at the carbon in dangling –CHO. This work provides us with a new insight into designing electrocatalysts based on COFs. [ABSTRACT FROM AUTHOR]