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Diabetic retinopathy (DR) is a very serious diabetes complication. Changes in the O-linked N-acetylglucosamine (O-GlcNAc) modification are associated with many diseases. However, its role in DR is not fully understood. In this research, we explored the effect of O-GlcNAc modification regulation by activating AMP-activated protein kinase (AMPK) in DR, providing some evidence for clinical DR treatment in the future. Bioinformatics was used to make predictions from the database, which were validated using the serum samples of diabetic patients. As an in vivo model, diabetic mice were induced using streptozotocin (STZ) injection with/without an AMPK agonist (metformin) or an AMPK inhibitor (compound C) treatment. Electroretinogram (ERG) and H&E staining were used to evaluate the retinal functional and morphological changes. In vitro, 661 w cells were exposed to high-glucose conditions, with or without metformin treatment. Apoptosis was evaluated using TUNEL staining. The protein expression was detected using Western blot and immunofluorescence staining. The angiogenesis ability was detected using a tube formation assay. The levels of O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA) in the serum changed in the DR patients in the clinic. In the diabetic mice, the ERG wave amplitude and retinal thickness decreased. In vitro, the apoptotic cell percentage and Bax expression were increased, and Bcl2 expression was decreased in the 661 w cells under high-glucose conditions. The O-GlcNAc modification was increased in DR. In addition, the expression of GFAT/TXNIP O-GlcNAc was also increased in the 661 w cells after the high-glucose treatment. Additionally, the Co-immunoprecipitation(CO-IP) results show that TXNIP interacted with the O-GlcNAc modification. However, AMPK activation ameliorated this effect. We also found that silencing the AMPKα1 subunit reversed this process. In addition, the conditioned medium of the 661 w cells may have affected the tube formation in vitro. Taken together, O-GlcNAc modification was increased in DR with photoreceptor cell degeneration and neovascularization; however, it was reversed after activating AMPK. The underlying mechanism is linked to the GFAT/TXNIP-O-GlcNAc modification signaling axis. Therefore, the AMPKα1 subunit plays a vital role in the process. [ABSTRACT FROM AUTHOR]

Exposure to chronic psychosocial stress is a risk factor for metabolic disorders. Because dipeptidyl peptidase‐4 (DPP4) and cysteinyl cathepsin K (CTSK) play important roles in human pathobiology, we investigated the role(s) of DPP4 in stress‐related adipocyte differentiation, with a focus on the glucagon‐like peptide‐1 (GLP‐1)/adiponectin‐CTSK axis in vivo and in vitro. Plasma and inguinal adipose tissue from non‐stress wild‐type (DPP4+/+), DPP4‐knockout (DPP4−/−) and CTSK‐knockout (CTSK−/−) mice, and stressed DPP4+/+, DPP4−/−, CTSK−/−, and DPP4+/+ mice underwent stress exposure plus GLP‐1 receptor agonist exenatide loading for 2 weeks and then were analyzed for stress‐related biological and/or morphological alterations. On day 14 under chronic stress, stress decreased the weights of adipose tissue and resulted in harmful changes in the plasma levels of DPP4, GLP‐1, CTSK, adiponectin, and tumor necrosis factor‐α proteins and the adipose tissue levels of CTSK, preadipocyte factor‐1, fatty acid binding protein‐4, CCAAT/enhancer binding protein‐α, GLP‐1 receptor, peroxisome proliferator‐activated receptor‐γ, perilipin2, secreted frizzled‐related protein‐4, Wnt5α, Wnt11 and β‐catenin proteins and/or mRNAs as well as macrophage infiltration in adipose tissue; these changes were rectified by DPP4 deletion. GLP‐1 receptor activation and CTSK deletion mimic the adipose benefits of DPP4 deficiency. In vitro, CTSK silencing and overexpression respectively prevented and facilitated stress serum and oxidative stress‐induced adipocyte differentiation accompanied with changes in the levels of pref‐1, C/EBP‐α, and PPAR‐γ in 3T3‐L1 cells. Thus, these findings indicated that increased DPP4 plays an essential role in stress‐related adipocyte differentiation, possibly through a negative regulation of GLP‐1/adiponectin‐CTSK axis activation in mice under chronic stress conditions. [ABSTRACT FROM AUTHOR]

By using the melt crystallization method, Tb 4 O 7 −MnO 2 co-doped glass-ceramics containing Y 2 Sn 2 O 7 were synthesized. The heat treatment for glass-ceramics was determined to be 700 °C/1.5 h using differential scanning calorimetry analysis, X-ray diffraction, scanning electron microscopy, and light transmittance curves. FTIR spectroscopy further confirmed the precipitation of the Y 2 Sn 2 O 7. Although MnO 2 was used as the Mn source in this experiment, the glass-ceramic showed the luminescent properties of Mn2+. The emission spectra and fluorescence decay curves of Tb 4 O 7 −MnO 2 co-doped glass-ceramics demonstrate the energy transfer phenomenon of Tb3+→Mn2+. When the doping concentration of MnO 2 increases, the glass-ceramics can realize tunable luminescence from green light to yellow light to orange light. At 473 K, the luminescence intensity of Tb3+ and Mn2+ were 84.3% and 33.0% of those at room temperature. In terms of absolute and relative sensitivity, the maximum values for glass-ceramics were 1.18 × 10−2 K−1 and 1.52% K−1. The minimum temperature resolution is 0.05 K at 298 K. It is demonstrated that the prepared Tb 4 O 7 −MnO 2 co-doped glass-ceramics containing Y 2 Sn 2 O 7 have a promising application in the field of optical temperature measurement. [ABSTRACT FROM AUTHOR]

Organic long-lived luminescent probes featuring thermally activated delayed fluorescence (TADF) or room temperature phosphorescence (RTP) have emerged as highly promising tools for time-resolved luminescence imaging (TRLI) and sensing (TRLS). Their unique advantage lies in their ability to effectively eliminate interference from short-lived background signals. By introducing an appropriate delay time between the short-lived autofluorescence and measure of the long-lived luminescence emitted by the probes, a background-free approach emerges, enabling the accurate detection and imaging of diverse biologically relevant species. This review provides a comprehensive overview of metal-free organic compound-based responsive probes utilizing TADF and RTP for TRLI and TRLS. It offers detailed insights into the design strategies and sensing principles employed by these probes. Furthermore, the review discusses the current challenges faced by researchers in this rapidly expanding field and highlights the future prospects for advancements in this area of study. [Display omitted] • Comprehensive review of recent progress in time-resolved biosensing and imaging using long-lived organic luminescent probes. • Discussion on photophysical properties and design strategies of small organic molecule-based TADF and RTP materials. • Exploration of challenges and future directions in utilizing TADF and RTP materials for biomedical applications. [ABSTRACT FROM AUTHOR]

A new fluorescent probe based on graphitic carbon nitride (g-C3N4) combined with molecularly imprinted silica was successfully fabricated and used to selectively recognize chlortetracycline (CTC). The g-C3N4 used in this study has the characteristics of low toxicity and high chemical stability. This synthetic composite was characterized by transmission electron microscopy, Fourier transform infrared spectroscopy, UV spectroscopy, X-ray diffraction, and fluorescence spectroscopy. The material was used to detect CTC by the fluorescence quenching technique. The fluorescence quenching was due to g-C3N4 and the benzene ring of CTC through π-π electron donor-acceptor interaction and electrostatic force. Hydrogen bonds formed between CTC and 3-aminopropyltriethoxysilane during the polymerization process. Eventually, a considerable amount of selective recognition holes were formed in the composite material and could specifically recognize the template molecule CTC. In addition, the probe strategy was successfully applied to milk analysis, and the recoveries ranged from 90.1% to 95.7%, with relative standard deviations of 1.8-2.8%; the detection limit for CTC was 8 ng mL-1. The results indicate that this method combined the sensitivity of fluorescence detection with the excellent selectivity of a molecularly imprinted polymer. The new material can be widely used in the detection of dairy products.Schematic of synthesis of the MIP-capped g-C3N4 by sol-gel reaction [ABSTRACT FROM AUTHOR]

Glutamine metabolism plays a pivotal role in cancer progression, immune cell function, and the modulation of the tumor microenvironment. Dysregulated glutamine metabolism has been implicated in cancer development and immune responses, supported by mounting evidence. Cancer cells heavily rely on glutamine as a critical nutrient for survival and proliferation, while immune cells require glutamine for activation and proliferation during immune reactions. This metabolic competition creates a dynamic tug-of-war between cancer and immune cells. Targeting glutamine transporters and downstream enzymes involved in glutamine metabolism holds significant promise in enhancing anti-tumor immunity. A comprehensive understanding of the intricate molecular mechanisms underlying this interplay is crucial for developing innovative therapeutic approaches that improve anti-tumor immunity and patient outcomes. In this review, we provide a comprehensive overview of recent advances in unraveling the tug-of-war of glutamine metabolism between cancer and immune cells and explore potential applications of basic science discoveries in the clinical setting. Further investigations into the regulation of glutamine metabolism in cancer and immune cells are expected to yield valuable insights, paving the way for future therapeutic interventions. [ABSTRACT FROM AUTHOR]

Improving water management capability is crucial for enhancing the performance and extending the lifespan of a proton exchange membrane fuel cell (PEMFC). To achieve this goal, this study investigates the coupling effects of geometric features induced by actual gas flow channel (GFC) manufacturing processes and the surface wettability on the dynamic droplet change by simulating 32 cases using the volume of fluid (VOF) method. In addition, the simulated dynamic characteristics of the droplets, such as the centroid position and droplet height, have been verified by comparing them with experimental observations. The reliable results of the simulation show that varied draft angles contribute to different local vortices in the flow channels, arousing two drainage mechanisms—spontaneous and overflow drainage. Besides, the compared results of velocity contours suggest that the curvature effect along the water movement direction could strengthen the speed-up effect around a water droplet, thereby facilitating its detachment. By contrast, a cross-section with filleted corners could cause velocity loss and poor drainage efficiency. A geometric structure with a draft angle of 30° and a bend radius of 1 mm of wavy GFC is beneficial to shorten the water removal time and minimize gas diffusion layer (GDL) water coverage. The hydrophobic treatment of the GDL and channel wall meets both criteria of rapidly reducing liquid water coverage on both the GDL surface and the entire channel. This study's findings are expected to guide the target of both geometric manufacturing and surface treatment processes. [Display omitted] • The 3D model was developed based on the manufacturing shape features. • Different gas flow channel inclination can alter the drainage mechanism. • Geometric structure and wettability of GFC affect the interaction of water-GFC. • The optimized strategy was provided for accelerating water removal. [ABSTRACT FROM AUTHOR]

Abstract: Green and efficient procedures are essential for the chemoselective hydrogenation of functionalized nitroarenes to form industrially important anilines. Herein, it is shown that visible‐light‐driven, chemoselective hydrogenation of functionalized nitroarenes with groups sensitive to forming anilines can be achieved in good to excellent yields (82–100 %) in water under relatively mild conditions and catalyzed by low‐cost and recyclable graphitic carbon nitride. The process is also applicable to gram‐scale reaction, with a yield of aniline of 86 %. A study of the mechanism reveals that visible‐light‐induced electrons are responsible for the hydrogenation reactions, and thermal energy can also promote the photocatalytic activity. A study of the kinetics shows that this reaction possibly occurs through one‐step hydrogenation or stepwise condensation routes. A wide range of applications can be expected for this green, efficient, and highly selective photocatalysis system in reduction reactions for the synthesis of fine chemicals. [ABSTRACT FROM AUTHOR]

Specifically, the authors have stated that the data presented in the paper is incomplete; that the analysis did not use appropriate statistical tests, and that the combination of these factors resulted in inaccurate conclusions that are not supported by the data. Dianquan Zhang and Haichun Zhou contributed equally to this study as co-first authors B Retraction Note To: Stem Cell Research & Therapy (2021) 12:2 b https://doi.org/10.1186/s13287-020-02030-w The Editors-in-Chief have retracted this paper after the authors reported discrepancies in the data. [Extracted from the article]

Exposure to chronic psychological stress (CPS) is an intractable risk factor for inflammatory and metabolic diseases. Lysosomal cysteinyl cathepsins play an important role in human pathobiology. Given that cathepsin S (CTSS) is upregulated in the stressed vascular and adipose tissues, we investigated whether CTSS participates in chronic stress-induced skeletal muscle mass loss and dysfunction, with a special focus on muscle protein metabolic imbalance and apoptosis. Eight-week-old male wildtype (CTSS+/+) and CTSS-knockout (CTSS−/−) mice were randomly assigned to non-stress and variable-stress groups. CTSS+/+ stressed mice showed significant losses of muscle mass, dysfunction, and fiber area, plus significant mitochondrial damage. In this setting, stressed muscle in CTSS+/+ mice presented harmful alterations in the levels of insulin receptor substrate 2 protein content (IRS-2), phospho-phosphatidylinositol 3-kinase, phospho-protein kinase B, and phospho-mammalian target of rapamycin, forkhead box-1, muscle RING-finger protein-1 protein, mitochondrial biogenesis-related peroxisome proliferator-activated receptor-γ coactivator-α, and apoptosis-related B-cell lymphoma 2 and cleaved caspase-3; these alterations were prevented by CTSS deletion. Pharmacological CTSS inhibition mimics its genetic deficiency-mediated muscle benefits. In C2C12 cells, CTSS silencing prevented stressed serum- and oxidative stress-induced IRS-2 protein reduction, loss of the myotube myosin heavy chain content, and apoptosis accompanied by a rectification of investigated molecular harmful changes; these changes were accelerated by CTSS overexpression. These findings demonstrated that CTSS plays a role in IRS-2-related protein anabolism and catabolism and cell apoptosis in stress-induced muscle wasting, suggesting a novel therapeutic strategy for the control of chronic stress-related muscle disease in mice under our experimental conditions by regulating CTSS activity. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the impact of academic self-efficacy on test anxiety among higher vocational students, as well as the role of sense of life meaning, fear of failure, and gender difference in mediating this relationship.Methods: A total of 2231 higher vocational students from Shandong Province were surveyed by means of Academic Self-efficacy Questionnaire, Meaning in Life Questionnaire, and Test Anxiety Scale.Results: There were significant negative correlations among academic self-efficacy, sense of life meaning, and test anxiety. Fear of failure was positively correlated with test anxiety. Sense of life meaning and fear of failure played a mediating role in the relationship between academic self-efficacy and test anxiety. The chain mediating effect was significant only in the female group, not in the male group. In contrast, academic self-efficacy indirectly predicted test anxiety by the independent mediating effect of sense of life meaning or fear of failure in the male group.Conclusion: Academic self-efficacy may influence test anxiety through the independent mediating effect of sense of life meaning, fear of failure, and the chain mediating effect, and there is a gender difference in these effects. [ABSTRACT FROM AUTHOR]

Dy 2 O 3 -doped transparent glass-ceramics containing Ca 2 Ti 2 O 6 crystal phase were synthesized by melting crystallization method. The optimum heat treatment condition was determined to be 710 °C/1.5 h by differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmittance curves. The optimal doped concentration of Dy 2 O 3 is 0.4 mol%. The effects of doping with different concentrations of Mg2+ and Sr2+ on the fluorescence intensity of glass-ceramics were discussed. In comparison to Sr2+, the addition of Mg2+ effectively increased the luminescence intensity of 0.4 mol% Dy 2 O 3 -doped glass-ceramics. Since Mg2+ has a smaller ionic radius, it has a larger Coulomb potential and is more attractive to O2−, which makes the three-dimensional skeleton of BO 6 tilt, and the symmetry of the structure deteriorates, resulting in enhanced luminescence. Comparison of 0.4 mol%Dy 2 O 3 -doped glass-ceramic and 8 mol%MgF 2 -0.4 mol%Dy 2 O 3 co-doped glass-ceramic, the fluorescence intensity increased by 56.8% at 484 nm and 83.5% at 577 nm, the optical band gap value was reduced from 2.7824 eV to 2.4341 eV. The findings suggest that Dy3+-doped glass-ceramics containing Ca 2 Ti 2 O 6 crystal phase will be used in white light-emitting diodes (W-LEDs). • The Dy3+ doped glass ceramic containing Ca 2 Ti 2 O 6 was synthesized. • The transmittance of glass ceramic can reach 76% in the visible region. • The optimal doped concentration of Dy 2 O 3 is 0.4 mol%. • The addition of Mg2+ results in enhanced luminescence intensity and reduced optical band gap. [ABSTRACT FROM AUTHOR]