Crystalline and porous covalent organic frameworks (COFs) and metal‐organic frameworks (MOFs) materials have attracted enormous attention in the field of photocatalytic H2 evolution due to their ...long‐range order structures, large surface areas, outstanding visible light absorbance, and tunable band gaps. In this work, we successfully integrated two‐dimensional (2D) COF with stable MOF. By covalently anchoring NH2‐UiO‐66 onto the surface of TpPa‐1‐COF, a new type of MOF/COF hybrid materials with high surface area, porous framework, and high crystallinity was synthesized. The resulting hierarchical porous hybrid materials show efficient photocatalytic H2 evolution under visible light irradiation. Especially, NH2‐UiO‐66/TpPa‐1‐COF (4:6) exhibits the maximum photocatalytic H2 evolution rate of 23.41 mmol g−1 h−1 (with the TOF of 402.36 h−1), which is approximately 20 times higher than that of the parent TpPa‐1‐COF and the best performance photocatalyst for H2 evolution among various MOF‐ and COF‐based photocatalysts.
Effective separation: A novel MOF/COF hybrid material assembled by covalent connecting two components, exhibits effective visible‐light‐driven photocatalytic H2 evolution due to the ideal band matching and effectively promoting the separation of the photogenerated charges and holes.
WRKY transcription factors play a key role in the tolerance of biotic and abiotic stresses across various crop species, but the function of some WRKY genes, particularly in tomato, remains ...unexplored. Here, we characterize the roles of a previously unstudied WRKY gene, SlWRKY8, in the resistance to pathogen infection and the tolerance to drought and salt stresses. Expression of SlWRKY8 was up‐regulated upon Pseudomonas syringae pv. tomato DC3000 (Pst. DC3000), abiotic stresses such as drought, salt and cold, as well as ABA and SA treatments. The SlWRKY8 protein was localized to the nucleus with no transcription activation in yeast, but it could activate W‐box‐dependent transcription in plants. The overexpression of SlWRKY8 in tomato conferred a greater resistance to the pathogen Pst. DC3000 and resulted in the increased transcription levels of two pathogen‐related genes SlPR1a1 and SlPR7. Moreover, transgenic plants displayed the alleviated wilting or chlorosis phenotype under drought and salt stresses, with higher levels of stress‐induced osmotic substances like proline and higher transcript levels of the stress‐responsive genes SlAREB, SlDREB2A and SlRD29. Stomatal aperature was smaller under drought stress in transgenic plants, maintaining higher water content in leaves compared with wild‐type plants. The oxidative pressure, indicated by the concentration of hydrogen peroxide (H2O2) and malondialdehyde (MDA), was also reduced in transgenic plants, where we also observed higher levels of antioxidant enzyme activities under stress. Overall, our results suggest that SlWRKY8 functions as a positive regulator in plant immunity against pathogen infection as well as in plant responses to drought and salt stresses.
Nanoscale metal–organic frameworks (NMOFs) have proven to be a class of promising drug carriers as a result of their high porosity, crystalline nature with definite structure information, and ...potential for further functionality. However, MOF‐based drug carriers with active tumor‐targeting function have not been extensively researched until now. Here we show a strategy for constructing active tumor‐targeted NMOF drug carriers by anchoring functional folic acid (FA) molecules onto the metal clusters of NMOFs. Two zirconium‐based MOFs, MOF‐808 and NH2‐UiO‐66, were chosen as models to reduce to the nanoscale for application as drug carriers, and then the terminal carboxylates of FA molecules were coordinated to Zr6 clusters on the surfaces of the nanoparticles by substitution of the original formate or terminal ‐OH ligands. The successful modification with FA was confirmed by solid‐state 13C MAS NMR and UV/Vis spectroscopy and other characterization methods. Drug loading and controlled release behavior at different pH were determined by utilizing the anticancer drug 5‐fluorouracil (5‐FU) as the model drug. Confocal laser scanning microscopy measurements further demonstrated that 5‐FU‐loaded FA‐NMOFs have excellent targeting ability through the efficient cellular uptake of FA‐NMOFs. This work opens up a new avenue to the construction of active tumor‐targeted NMOF‐based drug carriers with potential for cancer therapies.
Targeted drug delivery: Nanoscale metal–organic frameworks modified with folic acid (FA‐NMOFs) have been prepared as potential drug carriers for targeted delivery to tumor cells (see figure). The anticancer drug 5‐fluorouracil (5‐FU) was encapsulated in the pores of the FA‐NMOFs. The 5‐FU‐loaded FA‐NMOFs showed excellent biocompatibility and were found to effectively kill tumor cells through the targeting effect of the FA‐NMOFs.
Perovskite light‐emitting didoes (PeLEDs) have shown considerable potential in solution‐processable display applications. However, the performance of blue PeLEDs in terms of efficiency and stability ...hinders their practicality on account of severe trap‐mediated nonradiative recombination losses and halide phase segregation. To ameliorate these issues, mixed‐halide sky‐blue perovskite materials are strategically modulated through crystal defect passivation with a trifurcate isocyanate oligomer, which leads to the synergistical suppression of charge trap density and halide ion migration. The proposed approach enables the performance improvement for sky‐blue PeLEDs, exhibiting a peak external quantum efficiency of 14.82% and spectrally stable emission at 487 nm. In addition, prolonged operational lifetime and enhanced capability of moisture resistance are achieved simultaneously, approaching a half‐lifetime of ≈2900 s at an initial brightness of 178 cd m–2.
A trifurcate isocyanate oligomer is proposed for modulating mixed‐halide sky‐blue perovskite materials by passivating crystal defects, suppressing halide ion migration, and resisting moisture simultaneously. Sky‐blue perovskite light‐emitting diodes achieve a high external quantum efficiency of 14.82% and distinctly improved operational stability with a half‐lifetime of ≈3000 s.
Covalent organic frameworks (COFs) are an emerging type of crystalline and porous photocatalysts for hydrogen evolution, however, the overall water splitting activity of COFs is rarely known. In this ...work, we firstly realized overall water splitting activity of β-ketoamine COFs by systematically engineering N-sites, architecture, and morphology. By in situ incorporating sub-nanometer platinum (Pt) nanoparticles co-catalyst into the pores of COFs nanosheets, both Pt@TpBpy-NS and Pt@TpBpy-2-NS show visible-light-driven overall water splitting activity, with the optimal H
and O
evolution activities of 9.9 and 4.8 μmol in 5 h for Pt@TpBpy-NS, respectively, and a maximum solar-to-hydrogen efficiency of 0.23%. The crucial factors affecting the activity including N-sites position, nano morphology, and co-catalyst distribution were systematically explored. Further mechanism investigation reveals the tiny diversity of N sites in COFs that induces great differences in electron transfer as well as reaction potential barriers.
Filamentous fungal insect pathogens represent a source of biological insecticides and acaricides formulated using intact cells, such as conidia or other spores. These mycoinsecticides infect ...arthropod pests through cuticular penetration. In field application, formulated fungal cells are exposed to environmental stresses, including solar UV irradiation, high temperature, and applied chemical herbicides and fungicides, as well as stress from host immune defenses. These stresses often result in accumulation of toxic reactive oxygen species (ROS), generating oxidative stress to the fungal cells and hence affecting the efficacy and persistency of fungi formulated for pest control. In response, fungi have evolved effective antioxidant mechanisms that include enzyme families that act as ROS scavengers, e.g., superoxide dismutases, catalases, peroxidases, thioredoxins /thioredoxin reductases, and glutaredoxins/glutathione reductases. Over two dozen antioxidant enzymes dispersed in different families have been characterized in
Beauveria bassiana
in recent years. This mini-review focuses on the progress detailed in the studies of these enzymes and provides an overview of their antioxidant activities and contributions to conidial thermotolerance, UV resistance and virulence. These activities are crucial for the biological control potential of mycoinsecticide formulation and have significantly advanced our understanding of how these organisms work. Several potent antioxidant genes have been exploited for successful genetic engineering of entomopathogenic fungi aimed at enhancing their potential against arthropod pests.
Objective
To evaluate the role of immune cells and their effector cytokines in the pathogenesis and progression of knee osteoarthritis (OA) in matched OA synovial fluid (SF) and synovial tissue ...samples.
Methods
Cells from matched samples of synovial tissue and SF acquired from individuals undergoing total knee replacement for OA (n = 39) were characterized for immune cell–associated surface markers and intracellular cytokine expression using polychromatic flow cytometry. Additional individuals with radiographic knee OA (Kellgren/Lawrence severity grades ≥1) who had available etarfolatide (inflammatory cell) imaging (n = 26) or baseline and 3‐year data on progression of radiographic knee OA (n = 85) were also assessed. SF cytokine concentrations in all cohorts were evaluated for associations with synovial tissue and SF cell phenotypes and severity of radiographic knee OA.
Results
Macrophages (predominant in the synovial tissue, 53% of total cells) and neutrophils (predominant in the SF, 26% of total cells) were the major immune cell populations identified in the OA knee joints, exhibiting expression of or association with transforming growth factor β1 (TGFβ1) and elastase, respectively, in the SF. Expression levels of TGFβ1 and elastase were significantly associated with severity of radiographic knee OA. Baseline SF concentrations of TGFβ1 and elastase along with radiographic knee OA severity scores were predictive of knee OA progression, with areas under the receiver operating characteristic curves of 0.810 (for TGFβ1), 0.806 (for elastase), and 0.846 (for both TGFβ1 and elastase combined), with greater stability of prediction when both markers were utilized.
Conclusion
Our findings demonstrate the hitherto underappreciated role of neutrophils in the sterile inflammatory process and progression of OA. Two soluble mediators, SF elastase and TGFβ1, are strong predictors of knee OA progression, reflecting a synergistic role of neutrophil and macrophage populations in the pathogenesis and worsening of OA that could potentially be utilized to identify patients who may have a greater risk of more rapid disease progression.
Abstract
Long noncoding RNAs (lncRNAs) are known to regulate DNA damage response (DDR) and genome stability in proliferative cells. However, it remains unknown whether lncRNAs are involved in these ...vital biological processes in post-mitotic neurons. Here, we report and characterize a lncRNA, termed Brain Specific DNA-damage Related lncRNA1 (BS-DRL1), in the central nervous system. BS-DRL1 is a brain-specific lncRNA and depletion of BS-DRL1 in neurons leads to impaired DDR upon etoposide treatment in vitro. Mechanistically, BS-DRL1 interacts with HMGB1, a chromatin protein that is important for genome stability, and is essential for the assembly of HMGB1 on chromatin. BS-DRL1 mediated DDR exhibits cell-type specificity in the cortex and cerebellum in gamma-irradiated mice and BS-DRL1 knockout mice show impaired motor function and concomitant purkinje cell degeneration. Our study extends the understanding of lncRNAs in DDR and genome stability and implies a protective role of lncRNA against neurodegeneration.
Combination therapy has been regarded as a promising strategy for cancer treatment due to the enhanced anticancer efficacy achieved by blocking multiple drug resistance pathways. In this work, a drug ...carrier based on nanoscale ZIF-90 for the codelivery of two anticancer drugs has been synthesized by covalently attaching doxorubicin (DOX) to the surface of ZIF-90 via Schiff base reaction of amino group in DOX and aldehyde group of imidazole-2-carboxaldehyde (ICA) ligand and encapsulating 5-fluorouracil (5-FU) into the pores of the framework. The results of drug loading measurements show that the loading amount of drugs was estimated as high as 36.35 and 11-13.5 wt % for 5-FU and DOX, respectively. Moreover, we demonstrated that the carrier had the potential of cancer-targeted delivery of drugs for the collapse of framework under the pH environment around cancer cells and subsequently releasing drugs. Drug release at pH 5.5, imitating the environment of tumor, can reach over 95%, and the release time is less 16 h, meaning a more effective and faster release of drugs around tumoral cells than that in a normal environment. This is the first report for cancer-targeted codelivery of two different chemical drugs based on nanoscale metal-organic frameworks (NMOFs).
Artificial photosynthetic diluted CO2 reduction directly driven by natural sunlight is a challenging, but promising way to realize carbon‐resources recycling utilization. Herein, a three‐in‐one ...photocatalytic system of CO2 enrichment, CO2 reduction and H2O oxidation sites is designed for diluted CO2 reduction. A Zn‐Salen‐based covalent organic framework (Zn‐S‐COF) with oxidation and reductive sites is synthesized; then, ionic liquids (ILs) are loaded into the pores. As a result, EmimBF4@Zn‐S‐COF shows a visible‐light‐driven CO2‐to‐CO conversion rate of 105.88 µmol g−1 h−1 under diluted CO2 (15%) atmosphere, even superior than most photocatalysts in high concentrations CO2. Moreover, natural sunlight driven diluted CO2 reduction rate also reaches 126.51 µmol g−1 in 5 h. Further experiments and theoretical calculations reveal that the triazine ring in the Zn‐S‐COF promotes the activity of H2O oxidation and CO2 reduction sites, and the loaded ILs provide an enriched CO2 atmosphere, realizing the efficient photocatalytic activity in diluted CO2 reduction.
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