CYP2J2 and EETs Protect against Oxidative Stress and Apoptosis in Vivo

Background: Cytochrome P450 epoxygenase 2J2 (CYP2J2) metabolizes arachidonic acids to epoxyeicosatrienoic acids (EETs). EETs exert various biological effects, including anti-inflammatory, anti-apoptotic, pro-proliferation, pro-angiogenesis, anti-oxidation, and anti-fibrosis effects. However, little is known about the role of CYP2J2 and EETs in lung ischemia/reperfusion injury. In this study, we examined the effects of exogenous EETs or CYP2J2 overexpression on lung ischemia/reperfusion injury in vivo and in vitro. Methods and Results: CYP2J2 gene was stably transfected into rat lungs via pcDNA3.1-CYP2J2 plasmid delivery, resulting in increased EETs levels in the serum and lung. A rat model of lung ischemia/reperfusion injury was developed by clamping the left lung hilum for 1 hour, followed by reperfusion for 2 hours. We found that CYP2J2 overexpression markedly decreased the levels of oxidative stress and cell apoptosis in lung tissues induced by ischemia/reperfusion. Moreover, we observed that exogenous EETs, or CYP2J2 overexpression, enhanced cell viability, decreased intracellular reactive oxygen species (ROS) generation, inhibited mitochondrial dysfunction, and attenuated several apoptotic signaling events in a human pulmonary artery endothelial cells (HPAECs)-based anoxia/reoxygenation model. These apoptotic events included activation of NADPH oxidase, collapse of mitochondrial transmembrane potential, and activation of pro-apoptotic proteins and caspase-3. These effects were mediated, at least partially, by the PI3K/Akt signaling pathway. Conclusion: These results reveal that CYP2J2 overexpression and exogenous EETs can protect against oxidative stress and apoptosis following lung ischemia/reperfusion in vivo and in vitro, suggesting that increasing the level of EETs may be a novel promising strategy to prevent and treat lung ischemia/reperfusion injury

Room-Temperature Synthesis of Covalent Organic Framework (COF-LZU1) Nanobars in CO2/Water Solvent

The development of facile, rapid, low-energy, environmentally benign routes for the synthesis of covalent organic frameworks (COFs) is of great interest. This study concerns the utilization of water containing dissolved CO2 as a solvent for the room-temperature synthesis of COF. The as-synthesized particles, denoted COF-LZU1, combine advantages of good crystallinity, nanoscale size, and high surface area, which suggests promising application as a support for heterogeneous catalysts. Moreover, this versatile CO2-assisted method is also applicable for the room-temperature synthesis of Cu-COF-LZU1. This method gives rise to new opportunities for fabricating COFs and COF-based materials with different compositions and structures

How turbulence spreading improves power handling in quiescent high confinement fusion plasmas

Abstract: Viable magnetic fusion devices necessitate combining good confinement with effective power flux handling. A major concern for ITER, and devices beyond, is the divertor heat load width, which sets peak boundary heat loads on the plasma-facing materials. Current estimates of the heat flux width are narrow for future reactors. Here, we demonstrate how pedestal turbulence can expand into, or entrain, the stable scrape-off-layer and so broaden the heat flux width beyond these neoclassical predictions. Employing combined theoretical, computational, and experimental approaches, we focus on quiescent high confinement discharges on the DIII-D tokamak, but the results are of broader significance. Our findings uncover common trends in the edge turbulence intensity flux, the pressure perturbation skewness, and the turbulence mixing length, which together determine the heat flux width. This research demonstrates the physics of scrape-off-layer broadening by turbulence and highlights the promise of a turbulent pedestal for successful core-edge integration in ITER and future fusion devices

FANCA Promotes DNA Double-Strand Break Repair by Catalyzing Single-Strand Annealing and Strand Exchange

FANCA is a component of the Fanconi anemia (FA) core complex that activates DNA interstrand crosslink repair by monoubiquitination of FANCD2. Here, we report that purified FANCA protein catalyzes bidirectional single-strand annealing (SA) and strand exchange (SE) at a level comparable to RAD52, while a disease-causing FANCA mutant, F1263Δ, is defective in both activities. FANCG, which directly interacts with FANCA, dramatically stimulates its SA and SE activities. Alternatively, FANCB, which does not directly interact with FANCA, does not stimulate this activity. Importantly, five other patient-derived FANCA mutants also exhibit deficient SA and SE, suggesting that the biochemical activities of FANCA are relevant to the etiology of FA. A cell-based DNA double-strand break (DSB) repair assay demonstrates that FANCA plays a direct role in the single-strand annealing sub-pathway (SSA) of DSB repair by catalyzing SA, and this role is independent of the canonical FA pathway and RAD52. [Display omitted] •FANCA catalyzes bidirectional single-strand annealing and strand exchange•FANCG stimulates FANCA-mediated strand annealing and strand exchange•Fanconi anemia patient-derived FANCA mutants are deficient in both activities•The single-strand annealing activity of FANCA plays a direct role in DSB repair Benitez et al. report that FANCA biochemically catalyzes single-strand annealing and strand exchange. They find that the single-strand annealing activity of FANCA is relevant to the etiology of Fanconi anemia and responsible for its involvement in double-strand break repair, which is independent of the canonical FA pathway and RAD52

MIL-125-NH₂@TiO₂ Core–Shell Particles Produced by a Post-Solvothermal Route for High-Performance Photocatalytic H₂ Production

Metal–organic frameworks (MOFs) have proven to be an interesting class of sacrificial precursors of functional inorganic materials for catalysis, energy storage, and conversion applications. However, the controlled synthesis of MOF-derived materials with desirable compositions, structures, and properties still remains a big challenge. Herein, we propose a post-solvothermal route for the outer-to-inner loss of organic linkers from MOF, which is simple, rapid, and controllable and can be operated at temperature much lower than that of the commonly adopted pyrolysis method. By such a strategy, the MIL-125-NH₂ particles coated by TiO₂ nanosheets were produced, and the thickness of TiO₂ shell can be easily tuned. The MIL-125-NH₂@TiO₂ core–shell particles combine the advantages of highly active TiO₂ nanosheets, MIL-125-NH₂ photosensitizer, plenty of linker defects and oxygen vacancies, and mesoporous structure, which allows them to be utilized as photocatalysts for the visible-light-driven hydrogen production reaction. It is remarkable that the hydrogen evolution rate by MIL-125-NH₂@TiO₂ can be enhanced 70 times compared with the pristine MIL-125-NH₂. Such a route can be easily applied to the synthesis of different kinds of MOF-derived functional materials

Emerging frontiers: root and rhizosphere research inthe context of global environmental change

Plant Genome Research Program, National Science Foundation (USA) IOS-144444