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Oxygen evolution reaction (OER) plays a crucial role in developing energy conversion and adjusting electronic structure of the electrocatalysts can effectively improve the catalytic activity and stability. However, it is a challenge to adjust the electronic structure on two-dimensional iridium dioxide nanosheets (IrO2 NS), which have the advantages of high atom utilization. Here, we regulate the surface properties of IrO2 NS through sulfonated carbon dots (SCDs) to promote the OER catalytic process. The catalyst IrO2 NS/SCDs-2 exhibited excellent catalytic activity with a lower overpotential of 180 mV than IrO2 NS (230 mV) at the current density of 10 mA·cm−2 in a 0.5 M H2SO4 solution. And after 160 h of stability testing, the overpotential of IrO2 NS/SCDs-2 only decreased by 4 mV. Moreover, transient potential scanning test can visually demonstrate that the addition of SCDs improves the conductivity of the catalyst and increases the electron transfer rate. [ABSTRACT FROM AUTHOR]

Three-dimensional bioprinting is a potent biofabrication technique in tissue engineering but is limited by inadequate bioink availability. Plant-derived proteins are increasingly recognized as highly promising yet underutilized materials for biomedical product development and hold potential for use in bioink formulations. Herein, we report the development of a biocompatible plant protein bioink from pea protein isolate. Through pH shifting, ethanol precipitation, and lyophilization, the pea protein isolate (PPI) transformed from an insoluble to a soluble form. Next, it was modified with glycidyl methacrylate to obtain methacrylate-modified PPI (PPIGMA), which is photocurable and was used as the precursor of bioink. The mechanical and microstructural studies of the hydrogel containing 16% PPIGMA revealed a suitable compress modulus and a porous network with a pore size over 100 μm, which can facilitate nutrient and waste transportation. The PPIGMA bioink exhibited good 3D bioprinting performance in creating complex patterns and good biocompatibility as plenty of viable cells were observed in the printed samples after 3 days of incubation in the cell culture medium. No immunogenicity of the PPIGMA bioink was identified as no inflammation was observed for 4 weeks after implantation in Sprague Dawley rats. Compared with methacrylate-modified gelatin, the PPIGMA bioink significantly enhanced cartilage regeneration in vitro and in vivo, suggesting that it can be used in tissue engineering applications. In summary, the PPIGMA bioink can be potentially used for tissue engineering applications. [ABSTRACT FROM AUTHOR]

(1) Background: A rise in intraocular pressure (IOP) and decreased retinal ganglion cells are frequent indicators of effective modeling of chronic ocular hypertension in mice. In this study, the sensitivity of the mouse model to pharmaceutical therapy to reduce intraocular tension was assessed, the model's safety was confirmed using a cytotoxicity test, and the success rate of the mouse model of ocular hypertension was assessed by assessing alterations in IOP and neurons in the ganglion cell layer. (2) Methods: A mouse model of chronic ocular hypertension was produced in this study by employing photocrosslinkable sericin hydrogel injection and LED lamp irradiation. The eyes of 25 C57BL/6 male mice were subjected to 405 nm UV light from the front for 2 min after being injected with 5 μL of sericin hydrogel in the anterior chamber of the left eye. IOP in the mice was measured daily, and IOP rises greater than 5 mmHg were considered intraocular hypertension. When the IOP was lowered, the intervention was repeated once, but the interval between treatments was at least 2 weeks. The right eyes were not treated with anything as a normal control group. Mice eyeballs were stained with HE, Ni-type, and immunofluorescence to assess the model's efficacy. Two common drugs (tafluprost eye drops and timolol eye drops) were provided for one week after four weeks of stable IOP, and IOP changes were assessed to determine the drug sensitivity of the mouse model of chronic ocular hypertension. Furthermore, CellTiter 96® AQueous One Solution Cell Proliferation Assay (MTS) was utilized to investigate the safety of the ocular hypertension model by evaluating the deleterious effects of photocrosslinkable sericin hydrogel on cells. (3) Results: Before injection, the basal IOP was (9.42 ± 1.28) mmHg (1 kPa = 7.5 mmHg) in the experimental group and (9.08 ± 1.21) in the control group. After injection, cataract occurred in one eye, corneal edema in one eye, endophthalmitis in one eye, iris incarceration in one eye, and eyeball atrophy in one eye. Five mice with complications were excluded from the experiment, and twenty mice were left. Four weeks after injection, the IOP of the experimental group was maintained at (19.7 ± 4.52) mmHg, and that of the control group was maintained at (9.92 ± 1.55) mmHg, and the difference between the two groups was statistically significant (p < 0.05). Before the intervention, the IOP in the experimental group was (21.7 ± 3.31) mmHg in the high IOP control group, (20.33 ± 2.00) mmHg in the tafluprost eye drops group, and (20.67 ± 3.12) mmHg in the timolol maleate eye drops group. The IOP after the intervention was (23.2 ± 1.03) mmHg, (12.7 ± 2.11) mmHg, and (10.4 ± 1.43) mmHg, respectively. Before and after the intervention, there were no significant differences in the high-IOP control group (p > 0.05), there were statistically significant differences in the timolol eye drops group (p < 0.05), and there were statistically significant differences in the tafluprost eye drops group (p < 0.05). One week after drug withdrawal, there was no significant difference in IOP among the three groups (p > 0.05). In the high-IOP group, the protein (sericin hydrogel) showed a short strips or fragmented structure in the anterior chamber, accompanied by a large number of macrophages and a small number of plasma cells. The shape of the chamber angle was normal in the blank control group. The number of retinal ganglion cells decreased significantly 8 weeks after injection of sericin hydrogel into the anterior chamber, and the difference was statistically significant compared with the blank control group (p < 0.05). After the cells were treated with photocrosslinkable sericin hydrogel, there was no significant difference in the data of the CellTiter 96® assay kit of MTS compared with the blank control group (p > 0.05). (4) Conclusions: A mouse model of chronic intraocular hypertension can be established successfully by injecting sericin in the anterior chamber and irradiating with ultraviolet light. The model can simulate the structural and functional changes of glaucoma and can effectively reduce IOP after the action of most antihypertensive drugs, and it is highly sensitive to drugs. Sericin has no obvious toxic effect on cells and has high safety. [ABSTRACT FROM AUTHOR]

The utilization of two-dimensional (2D) nanosheets as catalysts is promising due to their atomic-scale thickness and extensive surfaces. The development of a high-quality, flexible Pt-based nanosheet with an efficient synthesis method is imperative. In this study, we present a 2D Pt2Pd porous alloy nanosheet synthesized through a novel process involving molten-alkali mechanochemical and borane morpholine complex reduction methods. This nanosheet exhibits a pristine 2D active surface, serving as an efficient catalyst for the oxygen reduction reaction (ORR). The Pt2Pd porous alloy nanosheet catalyst displays a high half-wave potential of 0.956 V versus the reversible hydrogen electrode (RHE), along with remarkable mass and specific activities of 1.38 A mg−1Pt and 3.70 mA cm−2 (at 0.9 V versus the RHE). When applied as the cathode in a zinc–air battery, it achieves a power density of 0.31 W cm−2 and demonstrates outstanding durability. This research introduces an innovative strategy for advancing high-quality, flexible 2D Pt-based materials. [ABSTRACT FROM AUTHOR]

PurposeMethodsResultsConclusionsThe burst of modern information has significantly promoted the development of global medicine into a new era of big data healthcare. Ophthalmology is one of the most prominent medical specialties driven by big data analytics. This study aimed to describe the development status and research hotspots of big data in ophthalmology.English articles and reviews related to big data in ophthalmology published from January 1, 1999, to April 30, 2024, were retrieved from the Web of Science Core Collection. The relevant information was analyzed and visualized using VOSviewer and CiteSpace software.A total of 406 qualified documents were included in the analysis. The annual number of publications on big data in ophthalmology reached a rapidly increasing stage since 2019. The United States (n = 147) led in the number of publications, followed by India (n = 77) and China (n = 69). The L.V. Prasad Eye Institute in India was the most productive institution (n = 50), and Anthony Vipin Das was the most influential author with the most relevant literature (n = 45). The electronic medical records were the primary source of ophthalmic big data, and artificial intelligence served as the principal analytics tool. Diabetic retinopathy, glaucoma, and myopia are currently the main topics of interest in this field.The application of big data in ophthalmology has experienced rapid growth in recent years. Big data is expected to play an increasingly significant role in shaping the future of research and clinical practice in ophthalmology. [ABSTRACT FROM AUTHOR]

Low tumor immunogenicity, immunosuppressive tumor microenvironment, and bacterial infections have emerged as significant challenges in postsurgical immunotherapy and skin regeneration for preventing melanoma recurrence. Herein, an immunotherapeutic hydrogel booster (GelMA-CJCNPs) was developed to prevent postoperative tumor recurrence and promote wound healing by incorporating ternary carrier-free nanoparticles (CJCNPs) containing chlorine e6 (Ce6), a BRD4 inhibitor (JQ1), and a glutaminase inhibitor (C968) into methacrylic anhydride-modified gelatin (GelMA) dressings. GelMA-CJCNPs reduced glutathione production by inhibiting glutamine metabolism, thereby preventing the destruction of reactive oxygen species generated by photodynamic therapy, which could amplify oxidative stress to induce severe cell death and enhance immunogenic cell death. In addition, GelMA-CJCNPs reduced M2-type tumor-associated macrophage polarization by blocking glutamine metabolism to reverse the immunosuppressive tumor microenvironment, recruiting more tumor-infiltrating T lymphocytes. GelMA-CJCNPs also downregulated IFN-γ-induced expression of programmed cell death ligand 1 to mitigate acquired immune resistance. Benefiting from the amplified systemic antitumor immunity, GelMA-CJCNPs markedly inhibited the growth of both primary and distant tumors. Moreover, GelMA-CJCNPs demonstrated satisfactory photodynamic antibacterial effects against Staphylococcus aureus infections, thereby promoting postsurgical wound healing. Hence, this immunotherapeutic hydrogel booster, as a facile and effective postoperative adjuvant, possesses a promising potential for inhibiting tumor recurrence and accelerating skin regeneration., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

A strain engineering strategy is crucial for designing a high-performance catalyst. However, how to control the strain in metastable phase two-dimensional (2D) materials is technically challenging due to their nanoscale sizes. Here, we report that cerium dioxide (CeO 2 ) is an ideal loading material for tuning the in-plane strain in 2D metastable 1T-phase IrO 2 (1T-IrO 2 ) via an in situ growth method. Surprisingly, 5% CeO 2 loaded 1T-IrO 2 with 8% compressive strain achieves an overpotential of 194 mV at 10 mA cm -2 in a three-electrode system. It also retained a high current density of 900 mA cm -2 at a cell voltage of 1.8 V for a 400 h stability test in the proton-exchange membrane device. More importantly, the Fourier transform infrared measurements and density functional theory calculation reveal that the CeO 2 induced strained 1T-IrO 2 directly undergo the *O-*O radical coupling mechanism for O 2 generation, totally different from the traditional adsorbate evolution mechanism in pure 1T-IrO 2 . These findings illustrate the important role of strain engineering in paving up an optimal catalytic pathway in order to achieve robust electrochemical performance.

Clarifying the structure-reactivity relationship of non-noble-metal electrocatalysts is one of the decisive factors for the practical application of water electrolysis. In this field, the anodic oxygen evolution reaction (OER) with a sluggish kinetic process has become a huge challenge for large-scale production of high-purity hydrogen. Here we synthesize a layered quasi-nevskite metastable-phase cobalt oxide (LQNMP-Co 2 O 3 ) nanosheet via a simple molten alkali synthesis strategy. The unit-cell parameters of LQNMP-Co 2 O 3 are determined to be a = b = 2.81 Å and c = 6.89 Å with a space group of P 3̅ m 1 (No. 164). The electrochemical results show that the LQNMP-Co 2 O 3 electrocatalyst enables delivering an ultralow overpotential of 266 mV at a current density of 10 mA cm geo -2 with excellent durability. The operando XANES and EXAFS analyses clearly reveal the origin of the OER activity and the electrochemical stability of the LQNMP-Co 2 O 3 electrocatalyst. Density functional theory (DFT) simulations show that the energy barrier of the rate-determining step (RDS) (from *O to *OOH) is significantly reduced on the LQNMP-Co 2 O 3 electrocatalyst by comparing with simulated monolayered CoO 2 (M-CoO 2 ).