Immune cells are essential components of the human immune system, playing a critical role in maintaining human health and defending against diseases. Changes in nutritional metabolism influence the activation, proliferation, apoptosis, differentiation direction, and other behaviors of immune cells, affecting immune function. Amino acids, fundamental nutrients in all living organisms, are crucial for maintaining redox balance, regulating energy, supporting biosynthesis, and preserving homeostasis. The availability of amino acids influences the behaviors and functions of immune cells significantly. Therefore, understanding the intricate relationship between amino acid metabolism and immune cell behavior leads to identifying unique therapeutic targets and improving clinical outcomes. The review summarizes the impact of different types of amino acid metabolism on the behaviors of dendritic cells and T cells, hoping to provide a valuable reference for researchers and clinicians in related fields.
The methane dry reforming (DRM) reaction can convert CO2 and CH4, both of which contribute to climate change, into syngas, which holds great significance in mitigating specific environmental issues stemming from the greenhouse effect. Nonetheless, the challenges that persist include the substantial energy consumption and the catalyst’s susceptibility to deactivation, both of which necessitate solutions. Herein, we developed a catalyst, PdCe/S1, featuring small-sized Pd species and CeO2 stabilized on pure silicon zeolite (silicalite-1), which is employed in the DRM reaction. It can achieve 97% CH4 conversion and 98% CO2 conversion at 750 °C, surpassing binary Pd/CeO2 and Pd/S1 catalysts. The small size of CeO2 stabilized by silicalite-1 promotes oxygen defects formation and enhances the CO2 adsorption capacity. The introduction of silicalite-1 further enhances the interaction between Pd and CeO2, boosting DRM performance.
Molecular dynamics simulations are conducted to investigate the deposition patterns of cyclic diblock copolymer solution nanodroplets on solid surfaces (walls). The primary focus is how initial polymer concentration, chain length, and solvent-wall interaction affect these patterns. Deposition patterns are categorized into phase diagrams, mainly composed of multihollow, coffee-ring, and multilayer structures. We also study the deposition of polymer blocks with different adsorption behavior by adjusting the interaction strength between the polymer block and the wall [ε A(B)W], including weakly adsorbable (ε A(B)W=0.6), moderately adsorbable (ε A(B)W=1.0), and strongly adsorbable (ε A(B)W=1.2) polymer blocks. This study identifies the key factors influencing the droplet’s deposition structure and elucidates the mechanisms behind pattern formation. The findings contribute to the design of deposition patterns for cyclic diblock copolymer solution nanodroplets, enhancing applications related to droplet evaporation.
We design and synthesize five novel diazocine derivatives, using diazocine as the core, amide or imine bonds as the connecting units attached with different peripheral substituents. The photoisomerization yield and thermal stability of these derivatives are tested by 1H NMR and UV-Vis absorption spectroscopy. Among them, the imine-linked derivative exhibits the lowest photoisomerization efficiency, while the amide-linked ones show an elevated switching efficiency in transitioning from the cis to the trans configuration, compared to the unmodified 3,3′-diamino-diazocine. Furthermore, based on experiments together with density functional theory (DFT) calculations, we find that the thermal stability of these derivatives is associated with the electron cloud density and steric hindrance of their substituents. Owing to these unique photophysical properties, diazocine derivatives provide a foundation for the development and application of molecular optical switches.
Oxygen vacancy in ceria is a crucial regulation factor for modifying materials. The reduced oxygen vacancy will undergo rapid recombination and deactivation due to the imbalance perturbation of active oxygen species, thereby restricting their larger-scale application. In this work, we proposed a strategy to stabilize oxygen vacancy in four black CeO x(Si) (0<x<2) by quartz sand doping reduction. The formation of a Ce-Ov-Si (Ov denoted as oxygen vacancy) interface, instrumental in constructing stable oxygen vacancies, is facilitated by rich hydroxyl groups. Characterizations of CeO x(Si) reveal that the heterogeneous hydrogen at the Ce-O-Si interface encourages the lattice distortion in ceria to obtain stable oxygen vacancies. Guided by the reusable feature, quartz sand doping reduction is a facile and feasible strategy to stabilize the oxygen vacancy of black CeO x for advanced materials on a large scale.
Indole derivatives, especially bisindolylesters, have attracted intense attention due to their important applications in medicinal chemistry and organic synthesis. Here we develop a Lewis acid-catalyzed efficient and regioselective strategy to prepare a series of symmetric and unsymmetric bisindolylesters in high to excellent yields under mild conditions. The systematic investigations, which include stoichiometric nuclear magnetic resonance (NMR) experiments and structural characterization of intermediates, have provided insights into the possible reaction mechanism for this B(C6F5)3-catalyzed addition reaction. Moreover, the sequential employment of Al(C6F5)3 and B(C6F5)3 as catalysts enabled us to successfully prepare the unsymmetric bisindolyl-compounds in one-pot two-step manner without the separation step.
This study introduces an innovative method for synthesizing mordenite (MOR) by employing a combination of water glass and fumed silica as the silica source. The zeolite produced through this method exhibits a smaller grain size, a larger specific surface area, and a greater number of Brønsted acid sites compared to the conventionally synthesized mordenite using silica sol. Furthermore, the chemical environment of framework Al in MOR zeolites is influenced by different silica sources, leading to varied acid properties between the two MOR zeolites, which results in an enhanced activity of dimethyl ether carbonylation from 50% to over 83%.
Vascular endothelial growth factor 2 (VEGFR2) plays a vital role in regulating of tumor metastasis and angiogenesis, which has emerged as one of the effective targets for clinical tumor therapy. Herein, a series of novel facilely accessible 4-phenoxyquinoline derivatives was prepared and assessed for their antitumor activity against three human tumor cell lines (SGC-7901, HepG2 and A549). Among these compounds, 6a, 6b and 6c show strong antitumor activity on HepG2 cells [the drug concentration of eliminating half of tumor cells (IC50)=9.33, 1.84, 8.54 μmol/L]. Notably, compound 6b shows potent selective inhibitory activity against VEGFR2 kinase with an IC50 value of 4.66 nmol/L. The excellent anti-angiogenesis capability of compound 6b was confirmed by tube formation and chick chorioallantoic membrane (CAM) assay. In vivo studies confirmed that compound 6b was able to inhibit tumor growth in HepG2 xenografts of BALB/c nude mice without obvious side or toxic effects. The results demonstrated that compound 6b exhibited remarkable anti-angiogenesis and tumor growth inhibitory effects with less toxicity in vitro and in vivo models. These findings highlighted the potential of compound 6b as a promising VEGFR2 kinase inhibitor for the development of antitumor drugs.
Herein, a turn-on fluorescent probe for the detection of lead ions was developed using 7-diethylaminocoumarin as the fluorophore and dibenzo-18-crown-6 as the recognition unit. The response performance to lead ions was systematically studied. The probe showed specific selectivity and high sensitivity to lead ions, with fluorescence intensity at 496 nm increasing linearly with lead ion concentration (R 2=0.995) over the range of 1.0×10−7–1.0×10−6 mol/L, and an LOD of 11.4 nmol/L. Job’s plot revealed that the probe forms a 1:1 stoichiometry complex with lead ions during the recognition process. Furthermore, the sensing mechanism of the probe was confirmed by density functional theory calculations, indicating that the recognition mechanism is based on photoinduced electron transfer (PET). The introduction of lead ions blocks PET, resulting in fluorescence enhancement. Finally, it was applied in the detection of practical water samples and bioimaging, demonstrating high application value in the field of chemosensors.
In this work, melanin nanoparticle-resveratrol (MNP-RES) nanosystem was excogitated and constructed for the treatment and imaging of folate-induced renal fibrosis (RF) mice model to fulfill the combination of diagnosis and therapeutic. Physicochemical characterization indicated that MNP-RES was a monodisperse spherical framework with a uniform diameter of (18.6±2.7) nm and the drug loading content of RES was 44.8%. The inhibition ratios of reactive oxygen species, such as ·OH, ·O2 −, ABTS’ and DPPH were all greater than 80%. After systemic therapy with MNP-RES, the levels of serum creatinine (SCr) and blood urea nitrogen (BUN) were decreased, and the extent of renal fibrosis was considerably relieved, which was verified by H&E, Masson and terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) staining. The MNP-RES nanosystem can diagnose and monitor the therapeutic efficacy of RF in real time and noninvasively via photoacoustic/magnetic resonance imaging (PA/MRI) dual-modality imaging, and the MNP-RES diagnostic-therapeutic nanosystem had satisfactory biocompatibility in vivo, which facilitated its future bio-transformation for RF treatment in clinical application.
Dysfunction of ion channels, often caused by mutations in natural proteins, can lead to various channelopathies. Their artificial analogs have shown great promise to substitute the abnormal channels. Here, we report a supramolecular potassium channel that forms through the self-assembly of pyrene-crown ether conjugated by intermolecular π-π interactions. The self-assembled dimer of this channel was optimized and calculated to have a binding energy of −27.4 kcal/mol (1 kcal=4.18 kJ). Evidence for the formation of an active ion channel by PC5 was confirmed using a planar lipid bilayer (BLM) workstation, while no such activity was observed for R-PC5. The K+/Na+ selectivity was reversed in the reduced form, R-PC5, due to the elimination of the planar structure of PC5, resulting in R-PC5 functioning as a Na+ carrier. Additionally, incorporating the pyrene group facilitates imaging in living cells, providing a potentially viable method for investigating the behaviors of artificial ion channels in living systems.
In view of recent environmental concerns, electrochemical water splitting for hydrogen (H2) as one of the important reactions has getting more and more attention in these years. Herein, we synthesized a series of Mo, N, and P co-doped carbons as efficient electrocatalysts to replace the expensive platinum-based catalysts. As the final products, the combination of Mo2C nanoparticles (NPs) and N, P co-doped carbons were fabricated using a simple molten salt process. More notably, KCl as the template could be recycled and reused via water washing. The ratios of the precursors could affect the structure of the final production, and therefore further determine the performance of electrocatalytic towards hydrogen evolution reaction (HER). Owing to extensive supplies of active sites and heterogeneous structures that provide transfer channels for electrons, the optimal sample of GUPMo-2.00KCl exhibited the best HER activity among the as-synthesized samples, including low overpotentials, small Tafel slope, and good stability. This work opens up a novel prospect for the designing of high-performance electrocatalysts.
Superhydrophobic coatings have tremendous potential for cotton fabric applications in antifouling and antibacterial. Despite great scientific and industrial interest in waterproof cellulosic cotton, its application in cotton fibres has been hindered by complicated processes, templates requirement, and limitations in scale-up production. Herein, we prepared a hydrophobic coating using one-step hydrolysis of siloxane. Through the reaction of long-chain organosilanes with acid, micro/nanostructures with low surface energy were constructed on the cotton fabric surface. Notably, the coating not only imparts self-cleaning and anti-bacterial adhesion properties to cotton fabrics, but also maintains a contact angle of over 140° after treatment with acid, alkali, organic solvents and extreme temperatures. In addition, the coating can be applied to a wide range of metals, plastics and paper to provide antifouling properties. This study believes that these excellent overall properties possess enormous potential for various applications involving anti-fouling.
The development of effective adsorbents with high amine efficiency and CO2 adsorption almost unaffected by humidity is extremely challenging. In this study, we introduce an innovative solid amine adsorbent, TETA/DEA@FS, composed of triethylenetetramine (TETA) and diethanolamine (DEA) functionalized fumed silica (FS), which exhibits exceptional capability in selectively capturing trace CO2 from N2. TETA/DEA@FS shows an exceptionally high capacity of CO2 adsorption of 1.13 mmol/g at the temperature of 298 K and the pressure of 0.0004 bar (1 bar=100 kPa), and achieves an unprecedented CO2/N2 IAST selectivity of 1.70×1012. TETA/DEA@FS exhibits high amine efficiency, with breakthrough experiments demonstrating that CO2 adsorption remains nearly unaffected by humidity. Meanwhile, TETA/DEA@FS demonstrates rapid CO2 adsorption kinetics and outstanding cyclic stability.
This study aimed to investigate the potential of chrysin (C) to induce osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) in vitro. Chitosan (CS) was dissolved by repeated freeze-thawing of alkali/urea solutions, followed by co-printing of nano-hydroxyapatite (HAP) powders with different concentrations of C solutions (5, 10, and 20 µmol/L) compounded into CS solution. Its rheological properties were modified with acetic acid/gelatin solution to construct C-CS-HAP (C-CS-H) composite scaffolds by extrusion printing technology. Physicochemical characterization showed that the four groups of scaffolds had regularly interconnected porous structures with pore diameters of about 450–600 µm, and the novel bioink exhibited shear-thinning properties, with the viscosity of the material decreasing in the shear rates range of 0.01–1000 s−1 and thus good printability. The osteogenic differentiation ability of BMSCs was confirmed by the CCK-8 test, alkaline phosphatase (ALP) test, Alizarin Red staining (ARS) test, osteogenesis-related genes OCN, ALP, Runx 2, and bone morphogenetic protein-2 (BMP-2) test, which showed a significant promotion of the osteogenic differentiation ability of BMSCs with the increase of the content of C. The above results indicate the potential of C-CS-H composite scaffolds in osteogenesis.