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Metal-organic polyhedra (MOPs) are discrete and intrinsically porous molecular self-assemblies. MOPs exhibit rich surface chemistry; the existence of peripheral reactive sites is exploited by post-synthetic covalent and/or coordination-based polymeric structures by maintaining MOP identities. By further treatment, the dimensions of cuboctahedral MOPs are manipulated in an unprecedented manner into next-generation metal/metal oxides-doped carbon polyhedron nanocages/nanospheres. Herein, the predesigned mixed metal and metal oxides dopped carbon nanopolyhedral spheres/cages (M/MO@CNS) are obtained through the pyrolysis of MOPs. These composites are characterized by FTIR, Raman, PXRD, BET, ICP, XPS, FE-SEM, and TEM techniques. The spherical morphology of the nanomaterial is preserved as carbon spheres doped with metal-based nanoparticles (Cu0Co0/Cu2OCoO@CNS), demonstrating excellent electrocatalytic performance. Compared to commercial iridium oxide, the carbon nanospheres incorporating metals/metal oxides presented a high activity profile for alkaline water oxidation. Catalysts prepared at 600°C and 1000°C revealed maximum current densities, as compared to the commercial IrO2 benchmark catalyst. The current densities of 10 mA/cm2 recorded low overpotentials/η10 and Tafel slopes than IrO2, with lower charge transfer resistance. Combined post-catalysis analyses and DFT calculations demonstrate that the synergistic interaction within Cu2O/CoO@CNS optimizes the electronic structure and promotes electron transfer. It also balances the free energies of key intermediates and reduces the energy barrier of the OER rate-determining step, resulting in enhanced catalytic performance. The MOPs derived next-generation carbon-nanocages are tested for catalytic stability via chronopotentiometry, which shows that these composites remained stable during several hours of electrolysis.

Unilateral ureteral obstruction (UUO) induces oxidative stress, inflammation, ferroptosis, and progressive fibrotic remodeling. Whether pharmacological modulation of ferroptosis-related redox imbalance attenuates obstructive kidney injury remains unclear. In this study, we investigated the effects of the thiol-containing antioxidant 2-mercaptoethanol (2-ME) in a mouse UUO model. Mice subjected to UUO received either pre-treatment or delayed treatment with 2-ME. Ferroptosis-related markers, including glutathione peroxidase 4 (GPX4), solute carrier family 7 member 11 (SLC7A11), the ratio of reduced to oxidized glutathione (GSH/GSSG), and lipid hydroperoxides, as well as inflammatory mediators, F4/80-positive macrophage infiltration, Havcr1 mRNA expression, and fibrotic parameters were evaluated using molecular and histological analyses. UUO markedly decreased the expression of GPX4 and SLC7A11, reduced the GSH/GSSG ratio, and elevated lipid hydroperoxide levels. These changes were accompanied by increased tubular injury scores, infiltration of F4/80-positive macrophages, and extracellular matrix accumulation. Pre-treatment with 2-ME increased GPX4 and SLC7A11 expression, improved the GSH/GSSG balance, reduced lipid hydroperoxide levels, and attenuated inflammatory activation. Additionally, 2-ME pre-treatment significantly reduced tubular injury scores and Havcr1 mRNA expression. However, 2-ME did not consistently suppress collagen deposition or the expression of fibrosis-related genes. Delayed administration of 2-ME failed to significantly alter antioxidant, inflammatory, or fibrotic markers. Pre-treatment with 2-ME attenuates ferroptosis-associated redox imbalance and inflammatory responses in UUO but does not consistently suppress tubulointerstitial fibrosis. These findings suggest that 2-ME can serve as a pharmacological tool to modulate thiol-dependent redox balance and inflammatory activation during UUO, whereas fibrosis progression likely involves additional mechanisms. Not applicable.

to determine the hypoglycemic and antioxidant effect of Sechium edule var. nigrum spinosum consumption in older Mexican adults with type 2 diabetes. a quasi-experimental study was conducted in 33 older adults with diabetes: 1) placebo group (PG; n = 14); 2) experimental group (EG; n = 19). The EG consumed 1.5 g of S. edule per day (three 500 mg capsules) for three months, and the PG consumed three placebo capsules of equal appearance for three months. Glycated hemoglobin (HbA1c), lipid peroxides (LPO), protein carbonylation (PC), total oxidative status (TOS), total antioxidant status (TAS), oxidative stress index (OSI), and the activity of the enzymes superoxide dismutase, glutathione peroxidase, and catalase were measured before and after the intervention in both groups. the EG showed a statistically significant decrease in HbA1c (EG: baseline, 8.9 ± 2.2; post. 7.8 ± 2.0), as well as in LPO, PC, TOS and OSI (LPO: baseline, 0.243 ± 0.067; post. 0.222 ± 0.050; PC: baseline, 29.4 ± 10; post. 19.2 ± 6; TOS: baseline, 6.0 ± 2.6; post. 3.1 ± 1.8; OSI: baseline, 5.7 ± 3.1; post 2.0 ± 1.1); along with a significant increase in TAS (baseline, 0.94 ± 0.29; post. 1.22 ± 0.28), changes that were not observed in the CG. the results suggest that S. edule has hypoglycemic and antioxidant effects.

Interfacial structure and its evolution play an important role in determining the functional properties of advanced materials and devices. However, real oxide heterointerfaces are typically far more complex than idealized abrupt boundaries; thus clarifying how interfacial structures evolve and how such evolution affects physical properties is essential. In this work, NiO/Cr2O3 heterostructures were epitaxially grown on single-crystalline SrTiO3 substrates by pulsed laser deposition under different deposition temperatures and subsequent post-annealing treatment, both of which strongly influence the thermally driven interfacial evolution. Interfacial structures were comprehensively characterized by high-resolution X-ray diffraction and transmission electron microscopy equipped with energy-dispersive X-ray spectroscopy. The evolution is revealed as a transition from an ultrathin interfacial transition zone in the as-deposited NiO/Cr2O3 heterostructure to the formation of a NiCr2O4 reaction interlayer, and finally to a NiO/NiCr2O4 bilayer after high-temperature annealing. Magnetic hysteresis loops measured by a superconducting quantum interference device reveal that all heterostructures exhibit weak ferrimagnetism, accompanied by a non-monotonic change in saturation magnetization with interfacial structural changes. These findings demonstrate that thermally controlled interfacial reactions and structural evolution can generate distinct magnetic characteristics, thereby providing a practical strategy for material interfaces design and performance engineering in functional oxides.

The escalating global demand for clean water necessitates the development of advanced membrane technologies capable of addressing complex contamination challenges and increasing the desalination efficiency. Polymeric membranes are commonly used due to their scalability and processability; however, their efficiency is limited by permeability-selectivity trade-offs and fouling. Polymer nanocomposite membranes (PNCMs) provide a promising substitute for the incorporation of functional nanofillers into polymer matrices for improving the separation efficiency. This review focuses on PNCMs for water purification and desalination, highlighting the importance of nanofillers like carbon nanotubes, graphene, and graphene oxide, metal and metal oxide nanoparticles (TiO2, ZnO, Ag), zeolites, and metal-organic frameworks. The influence of fabrication strategies, including phase inversion, electrospinning, and interfacial polymerization, on membrane structure-property relationships is systematically examined. While PNCMs demonstrate enhanced water permeability, selectivity, antifouling characteristics, and mechanical robustness compared to pristine membranes, their performance remains highly sensitive to nanofiller dispersion, interfacial compatibility, and structural stability. Key challenges, including nanoparticle agglomeration, long-term durability, and scalability constraints, are highlighted. Finally, future perspectives emphasize rational nanofiller design, controlled interface engineering, and scalable manufacturing approaches to enable the development of robust, high-performance membranes for sustainable water treatment.

Mutations in transmembrane channel-like protein 1 (TMC1), the pore-forming component of the mechano-electrical transducer (MET) channel in auditory hair cells, cause cell death and deafness in 3-wk old mice. We studied mice with mutations Tmc1 p.T416K, p.M412K, p.D528N, and p.D569N, which possessed functional MET channels at postnatal day (P)6 but became deaf before P21. These Tmc1 mutants had channels with reduced Ca2+ permeability and lower expression of the PMCA2 calcium pump in outer hair cell (OHC) stereocilia. The reduction in PMCA2 density was directly correlated with reduced Ca2+ entry via the MET channel. Over the first postnatal week, PMCA2 expression decreased in cochlear cultures containing lowered extracellular Ca2+, but after P11, PMCA2 density was insensitive to Ca2+ changes. The lower PMCA2 density in mutants was maintained into adulthood and may contribute to hair cell death. Before the onset of hearing, PMCA2 continuously turns over, and its insertion into stereocilia from an identified vesicular compartment is regulated by cytoplasmic [Ca2+]. PMCA2 turnover was strongly inhibited by the endocytosis blocker, Pitstop2, and by PtdIns(4,5)P2 blockers like phenylarsine oxide (PAO), which was shown to elevate stereociliary [Ca2+]. We argue the effects of PAO on mechanotransduction may be partly due to this Ca2+ increase. OHC bundles also expressed Neuroplastin (NPTN), a PMCA2 accessory protein, whose development paralleled PMCA2, and we propose it stabilizes the pump complex in stereocilia. NPTN expression was delayed about 2 d relative to PMCA2 and was less Ca2+ sensitive, implying it originates from a different internal pool of vesicles.

Hydrogels with high strength, stiffness, and toughness under full hydration are essential for load-transfer applications such as artificial tendons, ligaments, and soft robotics. Yet achieving such performance remains difficult because conventional polymer networks are intrinsically soft and transfer stress inefficiently. Here, a covalent interfacial anchoring (CIA) strategy is introduced to enable high-strength, high-stiffness hydrogel microfibers under full hydration by chemically anchoring carbon nanotubes (CNTs) and graphene oxide (GO) within poly(vinyl alcohol) networks. In this network, CNTs contribute to axial load transfer, whereas GO forms glutaraldehyde-mediated PVA-GO acetal linkages that suppress nanofiller mobility during deformation and promote efficient stress transfer. The resulting hydrogel fibers achieve tensile strength of 132 MPa, modulus of 1.1 GPa and toughness of 25 MJ m-3 under full hydration and maintain ∼88% displacement after 100 tendon-mimetic loading cycles. These findings highlight covalent interfacial anchoring as an effective strategy for engineering strong and stiff hydrogel fibers for tendon-like load-transfer applications.

A dual-mode sensing platform has been developed for ultrasensitive malathion (MAT) detection based on bifunctional rGO@ZnO/Zn-Fe3O4 composites (reduced graphene oxide-supported ZnO nanorods and Zn-doped Fe3O4 microspheres). The rGO@ZnO/Zn-Fe3O4 nanozyme is fabricated via a one-pot hydrothermal strategy and integrates favorable electrochemiluminescence (ECL) emission and intrinsic peroxidase-mimicking activity to realize dual-signal readout. In the K2S2O8 ECL system, Au NPs@UiO-66 serves as a coreactant booster to further magnify the ECL intensity of the composite. Meanwhile, the nanozyme catalyzes the H2O2-mediated oxidation of 3,3',5,5'-tetramethylbenzidine (TMB) to produce a colorimetric response. MAT suppresses both ECL and colorimetric responses by occupying Fe2+/Fe3+ catalytic sites and scavenging of reactive radicals. The sensor achieves limits of detection as low as 2.8 × 10-13 mol/L under ECL mode and 1.32 × 10-6 mol/L under colorimetric mode. In practical testing of MAT-spiked vegetable samples, the sensor exhibits acceptable recoveries and low relative standard deviations, demonstrating its practicability for field food safety supervision and rapid pesticide residue screening.

Zinc (Zn) is essential for immune cell function, while mesenchymal stem cells (MSCs) exert immunomodulatory effects primarily through the secretion of soluble factors. Considering the ability of MSCs and Zn to modulate the immune and inflammatory systems, this study investigated, in vitro, the effects of Zn supplementation on MSC responses to inflammatory stimuli and the subsequent modulation of macrophages and lymphocytes. Using the C3H10T1/2 line as a MSC model, we determined that 1 µM ZnSO4 enhanced MSC metabolic activity without affecting viability or cell-cycle distribution, whereas higher concentrations reduced cell viability. Under lipopolysaccharide (LPS) stimulation, Zn inhibited NFκB phosphorylation and increased AMPK phosphorylation, indicating anti-inflammatory and adaptive metabolic responses. Similarly, under TNF-α stimulation, Zn also reduced NFκB phosphorylation. Zn supplementation altered MSC secretory profiles, reducing IL-6, IL-10, and nitric oxide (NO) production while increasing TGF-β and prostaglandin E2 (PGE2) levels, indicating that Zn modifies MSC-derived soluble factor production under inflammatory conditions. Conditioned media from Zn-treated MSCs attenuated IL-6 and IL-12 production in macrophages, indicating a reduced pro-inflammatory cytokine response, whereas lymphocyte responses were unaffected. Importantly, Zn modulation of cytokine production was observed under LPS stimulation but not under TNF-α exposure, suggesting that Zn preferentially interferes with signaling pathways triggered by microbial stimuli. Overall, this study provides mechanistic insight into how Zn affects the secretory profile and inflammatory signaling pathways of C3H10T1/2 cells. These findings support further studies in primary MSCs to determine whether Zn supplementation may represent a useful strategy for modulating MSC-mediated immune regulation in therapeutic settings.

Rational structural design remains a key challenge in developing multifunctional membranes with high strength, flexibility, and excellent electromagnetic interference shielding effectiveness (EMI SE). Herein, poly(vinyl alcohol-co-ethylene) (PVA-co-PE) nanofibers and UHMWPE fibers were used as the base material and the reinforced framework, respectively. The 2D reduced graphene oxide (RGO) and 1D silver nanowires (AgNWs) with a long-to-short aspect ratio were introduced into the fiber cross-network. Then, the obtained composite membrane was cross-linked with an electron beam (EB) under the action of a crosslinking agent, resulting in high strength, high EMI SE, and multifunctionality. Notably, the obtained membrane exhibited an excellent EMI SE of 50.3 dB, which was attributed to the excellent conductive network formed by the complementary physical forms of conductive fillers, achieving efficient conductive loss and multi-level reflection loss. Moreover, the synergistic effect of the crosslinked structure and hydrogen bonds largely increased the tensile strength to 19.7 MPa, and its environmental stability had also been significantly improved. Additionally, the obtained membrane also demonstrated outstanding thermal management and flexibly defined the surface saturation temperature. This work had guiding significance for further expanding its application in intelligent wearable electronic products and the thermal therapy fields.

Inflammatory bowel disease (IBD) encompasses a group of common inflammatory intestinal disorders that are currently challenging to cure. Nanozymes, as an emerging class of therapeutics, hold significant promise in treating IBD. In this study, an ultrasmall, metal-free carbon nanozyme (GNZ) was synthesized from glucose through a one-step hydrothermal method. GNZ exhibited quantitatively characterized superoxide dismutase (SOD)-mimicking catalytic activity and broad-spectrum antioxidant capacity against multiple reactive oxygen and nitrogen species. In LPS-stimulated macrophages, GNZ reduced intracellular oxidative stress and the expression of pro-inflammatory markers while promoting an anti-inflammatory macrophage phenotype. Moreover, oral administration of GNZ alleviated disease symptoms, increased colon length, and reduced colonic tissue injury in DSS-induced colitis mice. These findings demonstrate the potential of glucose-derived GNZ as an orally administered antioxidant nanozyme for alleviating intestinal inflammation.

Calcium oxalate nephrolithiasis is strongly associated with oxidative stress, renal tubular injury, and inflammation. Natural products rich in polyphenols may serve as promising complementary preventive strategies. This study investigated the antiurolithiatic and renoprotective effects of Rhus coriaria fruit extract in an ethylene glycol-induced rat model of nephrolithiasis. Forty-two male rats were randomized into seven groups (n = 6): control, ethylene glycol (EG), EG + potassium citrate, R. coriaria 250 mg/kg/day, R. coriaria 500 mg/kg/day, EG + R. coriaria 250 mg/kg/day, and EG + R. coriaria 500 mg/kg/day. Nephrolithiasis was induced with 1% ethylene glycol for 28 days. Serum biochemistry, urinary lithogenic parameters, oxidative stress markers including total antioxidant status (TAS), total oxidant status (TOS), superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA), histopathology, and immunohistochemical expression of kidney injury molecule-1 (KIM-1) and osteopontin (OPN) were evaluated. Phytochemical characterization of the extract was performed by high-performance liquid chromatography coupled with diode-array detection (HPLC-DAD). Gallic acid was identified as the predominant phenolic constituent, together with smaller amounts of protocatechuic acid and ellagic acid. Ethylene glycol significantly increased urinary lithogenic parameters, oxidative stress indices, crystal deposition, tubular injury, and OPN expression. Treatment with R. coriaria significantly reduced urinary oxalate and calcium levels, improved TAS, SOD, and CAT levels, lowered TOS and MDA concentrations, and markedly attenuated crystal deposition, inflammation, and tubular dilatation. OPN expression was substantially decreased in treated groups, whereas KIM-1 showed a decreasing trend. Protective effects were more pronounced at the 500 mg/kg/day dose. R. coriaria fruit extract exerted significant antiurolithiatic and renoprotective effects in experimental calcium oxalate nephrolithiasis. These findings suggest that R. coriaria may represent a potential adjunctive strategy for calcium oxalate stone disease.

Perovskite/organic tandem solar cells (TSCs) offer a compelling route to surpass the Shockley-Queisser limit. In these TSCs, the self-assembled monolayer (SAM), functioning as the hole extraction layer, critically governs the interfacial properties and device performance. Atomic layer deposition (ALD) is a promising technique to grow dense, pinhole-free oxides on SAMs for improved wettability and leakage blocking. However, the detrimental reaction between the ALD precursor and SAM anchoring groups, which causes SAM desorption and severe current leakage, is a widespread and unresolved issue. To address this fundamental challenge, we developed a universal sacrificial coordination (SC) strategy by introducing a multifunctional 6‑hydroxy‑4‑(trifluoromethyl)nicotinic acid (HTFNA) into SAM precursors. HTFNA can suppress SAM molecular aggregation through hydrogen bonding, preferentially react with the ALD precursor to shield the anchored SAM, and increase the work function for favorable interfacial energy level alignment. This strategy demonstrates broad applicability across various SAM-based devices. The champion perovskite/organic TSCs deliver a remarkable efficiency of 27.03% (certified of 26.56%; 0.062 cm2). Moreover, the reinforced SAM/perovskite heterointerface exhibits substantially enhanced adhesion according to the ASTMD3359 standard, leading to superior operational stability (T90 of 1265 h) and ambient storage performance (T90 of 2037 h; ISOS-D-1 protocol).

The bacterium Zymomonas mobilis is widely studied for its potential as an industrial biofuel producer. Anoxic fermentation by Z. mobilis in lignocellulosic hydrolysate can generate bioethanol from renewable plant biomass. In this study, we deleted a gene from the Z. mobilis genome encoding a homolog of OxyR, a transcription factor that activates an oxidative stress response in bacteria to reduce reactive oxygen species (ROS). Deletion of this transcription factor inhibited growth of Z. mobilis in oxic, but not anoxic, conditions in laboratory media. A ROS probe revealed that the oxyR response is required to reduce intracellular ROS during oxic growth. Importantly for biofuel production, the absence of oxyR inhibited growth and delayed ethanol production during anoxic hydrolysate fermentation. To determine the source of oxidative stress in hydrolysates, we grew ΔoxyR in a synthetic hydrolysate containing known inhibitors found in hydrolysates. There was no growth defect in ΔoxyR in the synthetic hydrolysate, indicating that known inhibitory compounds are not the source of anoxic oxidative stress. We determined that ammonia-fiber expansion switchgrass hydrolysate contains significant peroxide concentrations. Addition of catalase to hydrolysate improves growth of both ΔoxyR and wild-type Z. mobilis in hydrolysate. This study uncovers an important source of stress to Z. mobilis during biofuel fermentation.IMPORTANCEFermentation of non-food biomass is a promising avenue for sustainable production of fuels and chemicals, but several challenges currently limit the applicability of this technology. One major hurdle is that when biomass is deconstructed into a fermentable form, many byproducts are generated that inhibit microbial fermentation. Here, we investigated how a fermentative bacterium, Zymomonas mobilis, experiences oxidative stress during anoxic biomass fermentation and identified genes important in this response. These findings provide a better understanding of the stresses faced by Z. mobilis during biofuel production. Fully understanding the effects of hydrolysates on biofuel-producing microbes is crucial for optimizing production and making carbon-neutral fuel a reality.

Lead (Pb) is one of the most prevalent environmental toxicants and is of great concern due to its adverse effects. Despite lead's oxidative properties, studies on the transgenerational effects of paternal Pb exposure remain inadequate. This study aimed to evaluate these effects on oxidative stress and the expression of specific genes using the D. melanogaster model. Male fruit flies were fed a normal diet supplemented with lead acetate as the Pb source for 20 consecutive days. The Pb-exposed males were mated with unexposed females, producing F1 offspring. F1 flies were fed a normal diet, and then bred to produce F2; F3 was produced from F2. All F1-F3 generations were kept on a normal diet, with no Pb exposure. Antioxidant parameters, including vitamins A, C, and E; reduced glutathione (GSH); catalase; superoxide dismutase (SOD); malondialdehyde (MDA); and the expression of CAT and SOD1 mRNA, were evaluated. There was a significant (p&#x2009;<&#x2009;0.05) decrease in antioxidant vitamin levels, GSH content, and catalase and SOD activities across F1-F3 due to exposure to the grandparent (F0). Similarly, a significant (p&#x2009;<&#x2009;0.05) elevation in MDA levels was observed across the F1-F3 generations due to exposure of the F0 generation. Significant down-regulation of the antioxidant genes CAT and SOD1 was also detected. The findings indicate persistent transgenerational alterations in oxidative stress biomarkers and antioxidant gene expression resulting from paternal Pb exposure. This underscores the importance of studying multiple generations to assess the health and environmental risks posed by pollutants.