Facilitating Proton Coupled Electron Transfer Reaction through the Interfacial Micro Electric Field with Fe─N4 ─C in FeMOFs Glass.

The proton-coupled electron transfer(PCET) reaction plays a crucial role in the chemical transformation process andhas become one of the most concerned elementary reactions. However, the complex kinetics of PCET reaction, which requires the simultaneous transfer of protons and electrons, leads to the dilemma that thermodynamics and kinetics cannot bebalanced and restricts its further development. In this, an interface micro-electric field (IMEF) basedon Fe─N4 in FeMOFs (Fe-Based Metal-Organic Frameworks) glass is designed tosynchronize proton/electron interface behavior for the first time to realizeefficient PCET reaction and optimize reaction thermodynamics and kinetics. The IMEF facilitates the separation of photogenerated electrons and holes, and accelerates Fe(III)/Fe(II) cycle. Driven by near-surface electric field force, the protons near surfacemigrate to Fe sites and participate in Fe(IV)═O formation and reaction, lowering the reaction energy barrier. Based on the interface regulation ofIMEF, a high-efficiency PCET reaction is realized, and kinetic reactionrate constant of photocatalytic oxidation of emerging contaminants is increasedby 3.7 times. This study highlights a strategy for IMEFs to modulate PEC Treactions for a wide range of potential applications, including environmental and ecological applications.

Myeloid leukemia-derived galectin-1 downregulates CAR expression to hinder cytotoxicity of CAR T cells.

BACKGROUND: Chimeric antigen receptor (CAR) T cells have shown significant activity in B-lineage malignancies. However, their efficacy in myeloid leukemia has not been successful due to unclear molecular mechanisms. METHODS: We conducted in vitro and in vivo experiments to investigate whether myeloid leukemia cells directly induce CAR down-regulation. Furthermore, we designed a CD33 CARKR in which all lysines in the cytoplasmic domain of CAR were mutated to arginine and verified through in vitro experiments that it could reduce the down-regulation of surface CARs and enhance the killing ability. Transcriptome sequencing was performed on various AML and ALL cell lines and primary samples, and the galectin-1-specific inhibitory peptide (anginex) successfully rescued the killing defect and T-cell activation in in vitro assays. RESULTS: CAR down-regulation induced by myeloid leukemia cells under conditions of low effector-to-tumor ratio, which in turn impairs the cytotoxicity of CAR T cells. In contrast, lysosomal degradation or actin polymerization inhibitors can effectively alleviate CAR down-regulation and restore CAR T cell-mediated anti-tumor functions. In addition, this study identified galectin-1 as a critical factor used by myeloid leukemia cells to induce CAR down-regulation, resulting in impaired T-cell activation. CONCLUSION: The discovery of the role of galectin-1 in cell surface CAR down-regulation provides important insights for developing strategies to restore anti-tumor functions.

Exogenous 2-(3,4-Dichlorophenoxy) triethylamine alleviates salinity stress in maize by enhancing photosynthetic capacity, improving water status and maintaining K+/Na+ homeostasis.

BACKGROUND: Soil salinity restricts plant growth and productivity. 2-(3,4-dichlorophenoxy) triethylamine (DCPTA) can alleviate salinity stress in plants. However, the mechanism of DCPTA-mediated salinity tolerance has not been fully clarified. We aimed to investigate its role in enhancing photosynthetic capacity, improving water status, maintaining K+/Na+ homeostasis and alleviating salinity stress in maize (Zea mays L.). RESULTS: In present study, maize seedlings were grown in nutrient solutions with a combination of NaCl (0, 150 mM) and DCPTA (0, 20, 100, and 400 µM). And photosynthesis, water status, ion homeostasis and the expression of genes involved in ion uptake and transport were evaluated in the maize seedlings. The results demonstrated that DCPTA alleviated the growth inhibition of maize seedlings exposed to salinity stress by increasing the net photosynthetic rate (Pn) and the quantum efficiency of photosystem II (PSII) photochemistry. DCPTA improved the root hydraulic conductivity, which help maintained the water status. A relatively high K+ concentration but a relatively low Na+ concentration and the Na+/K+ ratio were observed in the presence of DCPTA under salinity stress. Additionally, DCPTA altered the expression of four genes (ZmSOS1, ZmHKT1, ZmNHX1 and ZmSKOR) that encode membrane transport proteins responsible for K+/Na+ homeostasis. CONCLUSIONS: DCPTA improved the salinity tolerance of maize may be associated with enhanced photosynthetic capacity, maintenance of water status and altered expression of genes involved in ion uptake and transport.

Mechanism of directed activation of peroxymonosulfate by Fe-N/O unsymmetrical coordination-modulated polarized electric field.

Iron-nitrogen co-doped carbon materials as heterogeneous catalysts have attracted much attention in advanced oxidation processes involving peroxymonosulfate (PMS) due to their unique structure and enormous catalytic potential. However, there is limited research on the influence of different coordination structures on the central iron atoms. Through simple pyrolysis, we introduced oxygen atoms into the Fe-N coordination structure, constructing Fe-N/O@C catalysts with Fe-N2O2 coordination structure, and achieved efficient degradation of bisphenol A (BPA). Quenching experiments, electron paramagnetic resonance, and electrochemical analysis indicate that compared to the free radical activation pathway of Fe-N@C, high-valent iron-oxo species (≡Fe(Ⅳ) = O) are the main reactive oxygen species (ROS) in the Fe-N/O@C/PMS system. Meanwhile, we compared the differences in the oxidation states of Fe atoms and electron density in different coordination structures, revealing the formation of high-valent iron-oxo species and the mechanism of interfacial electron transfer. Therefore, this study provides new insights into the design and development of Fe-N co-doped catalysts for resource-efficient and environmentally friendly catalytic oxidation systems.

Characterization of three lamp genes from largemouth bass (Micropterus salmoides): molecular cloning, expression patterns, and their transcriptional levels in response to fast and refeeding strategy.

Lysosomes-associated membrane proteins (LAMPs), a family of glycosylated proteins and major constituents of the lysosomal membranes, play a dominant role in various cellular processes, including phagocytosis, autophagy and immunity in mammals. However, their roles in aquatic species remain poorly known. In the present study, three lamp genes were cloned and characterized from Micropterus salmoides. Subsequently, their transcriptional levels in response to different nutritional status were investigated. The full-length coding sequences of lamp1, lamp2 and lamp3 were 1251bp, 1224bp and 771bp, encoding 416, 407 and 256 amino acids, respectively. Multiple sequence alignment showed that LAMP1-3 were highly conserved among the different fish species, respectively. 3-D structure prediction, genomic survey, and phylogenetic analysis were further confirmed that these genes are widely existed in vertebrates. The mRNA expression of the three genes was ubiquitously expressed in all selected tissues, including liver, brain, gill, heart, muscle, spleen, kidney, stomach, adipose and intestine, lamp1 shows highly transcript levels in brain and muscle, lamp2 displays highly expression level in heart, muscle and spleen, but lamp3 shows highly transcript level in spleen, liver and kidney. To analyze the function of the three genes under starvation stress in largemouth bass, three experimental treatment groups (fasted group and refeeding group, control group) were established in the current study. The results indicated that the expression of lamp1 was significant induced after starvation, and then returned to normal levels after refeeding in the liver. The expression of lamp2 and lamp3 exhibited the same trend in the liver. In addition, in the spleen and the kidney, the transcript level of lamp1 and lamp2 was remarkably increased in the fasted treatment group and slightly decreased in the refed treatment group, respectively. Collectively, our findings suggest that three lamp genes may have differential function in the immune and energetic organism in largemouth bass, which is helpful in understanding roles of lamps in aquatic species.

Regulating Interlayer Confinement FeOCl for Accelerating Polymerization of Pollutants to Reduce Carbon Emission in Water Purification.

The spatial structure regulation of catalysts could optimize the reaction pathway and enhance the mass transfer kinetics, which might realize the efficient and low-consumption removal of pollutants in Fenton-like technology. In this study, N,N-dimethylformamide (DMF) intercalation was used to adjust the interlayer spacing of FeOCl from 7.90 to 11.84 Å by a simple and rapid intercalation method, thereby enhancing the mass transfer kinetics and altering the catalytic pathway. The removal rate of BPA in the DMF-FeOCl/PS system increased by 8.78 times, showing good resistance to complex water environments (such as pH, humic acid, and anions), especially in 5 g/L high-salt wastewater. The direct electron transfer processes between Fe(IV) and pollutants mediated by interlayer Fe sites generate phenoxy radicals, and the polymerization processes occur, achieving efficient removal of pollutants and low CO2 emissions. This study provides new insight into the efficient and low-carbon treatment of high-salt wastewater.

Unraveling the single-atom Fe-N4 catalytic site selectivity generate singlet oxygen via activation of persulfate: Polarizing electric fields changes the electron transfer pathway.

Single-atom catalysts have been proved to be an effective material for the removal of organic pollutants from water and wastewater, and yet, the relationship between their internal structures and their roles still remains elusive. In this work, a catalyst Fe (MIL)-SAC with single-atom Fe-N4 active site was prepared. Fe (MIL)-SAC/Peroxydisulfate (PDS) system was able to achieve complete degrade of the Sulfamethoxazole (SMX) with kobs at 0.466 min-1, which was faster than the Fenton system under the same conditions (kobs = 0.422 min-1) and 16 times faster than Fe (MIL) (kobs = 0.029 min-1). Density functional calculations reveal that the Fe-N4 structure will affect the electron transport path and lead to selective generation of 1O2 by triggering S-O breakage and O-O polarization in PDS. Furthermore, Fe (MIL)-SAC/PDS system exhibits strong resistance to common influencing factors and has good application prospects. This work provides a new approach for the selectively generation of 1O2 for the efficient treatment of organic pollutants in aqueous environment.

Exploring degradation properties and mechanisms of emerging contaminants via enhanced directional electron transfer by polarized electric fields regulation in Fe-N4-Cx.

Heterogeneous catalysis offers an opportunity to overcome the low efficiency and secondary pollution limitations of emerging contaminants (ECs) purification technologies, but it is still challenging to regulate electron directed transport for achieving high catalysis efficiency and selectivity due to insufficient understanding of the electron transfer pathways and behavioral mechanisms during its catalysis. Here, by tuning the defects of the C-N coordination of the support, the polarized electric field (PEF) characteristics are changed, which in turn affects the electron transport behavior. The results show that the charge offset on Fe-N4-Cx forms a PEF, which will induce directional electron transport. After the quantitative structure-activity relationship (QSAR) fitting analysis, the greater the degree of C-N defects, the higher the intensity of the PEF, which in turn enhances the electron transport and promotes the catalytic behavior. In addition, the surface pyrrole N site can adsorb enrofloxacin (ENR) and enrich it on the surface. This can reduce the transport distance of reactive oxygen species (ROS) to synergize catalysis and adsorption, resulting in rapid degradation of ECs. Combined with liquid chromatograph mass spectrometer (LC-MS) results and theoretical calculations, five degradation pathways of ENR were speculated, mainly including the oxidation of piperazine and the cleavage of the quinolone ring. This work proposes a novel PEF regulation strategy and explores its mechanism for safe treatment of ECs.

Revealing the synergistic mechanism of the generation, migration and nearby utilization of reactive oxygen species in FeOCl-MOF yolk-shell reactors.

Fenton-like reactions is attractive for environmental pollutant control, but there is an urgent need to improve the utilisation of hydroxyl radicals (·OH) in practical applications. Here, for the first time, FeOCl is encapsulated within a Metal Organic Framework (MOF) (Materials of Institut Lavoisier-101 (MIL-101(Fe))) as a yolk-shell reactor (FeOCl-MOF) by in situ growth. The interaction between FeOCl and the MOF not only increases the electron density of FeOCl, but also shifts down the d-band centre. The increase of electron density could promote the efficient conversion of H2O2 to ·OH catalysed by FeOCl. And the shift of the d-band centre to the lower energy level facilitates the desorption of ·OH. Experimental and theoretical calculations showed that the high catalytic performance was attributed to the unique yolk-shell structure that concentrates the catalytic and adsorption sites in a confinement space, as well as the improved electron density and d-band centre for efficient generation, rapid desorption and utilized nearby of ·OH. Which is utilized nearby by the organic pollutants adsorbed by the surface MOF, thus greatly improving the effective conversion of H2O2 and the ·OH utilisation (from 25.5% (Fe2+/H2O2) to 77.1% (FeOCl-MOF/H2O2)). In addition, a catalytic reactor was constructed to achieve continuous efficient treatment of organic pollutants. This work provides a Fenton-like microreactor for efficient generation, rapid desorption, and nearby utilization of ·OH to improve future technologies for deep water purification in complex environments.

Preclinical Evaluation of CD64 As a Potential Target For CAR-T-cell Therapy For Acute Myeloid Leukemia.

The relapsed and refractory acute myeloid leukemia (AML) patients receiving traditional chemotherapies have poor survival rate. Chimeric antigen receptor (CAR)-modified T cells have demonstrated remarkable effectiveness against some malignancies. However, most of CAR-Ts targeting the candidate proteins on AML cells induce hematopoietic cell suppression. Because of extensive heterogeneity among different types of AML, it is essential to expand the choice of target antigen for the CAR-T treatment of AML. CD64 (FcγRI) is a transmembrane protein with broad expression on various types of AML cells, especially monocytic AML cells, but it is absent on hematopoietic stem cells (HSCs) and most of nonmonocytes. Here, we found that some types of AML patients showed the homogeneous high-level expression of CD64. So, we created a CAR-T targeting CD64 (64bbz) and further verified its high efficiency for eradicating CD64+AML cells. In addition, 64bbz showed no cytotoxicity to HSCs. Overall, we developed a new treatment option for AML by using CD64 CAR-T cells while avoiding ablation of HSCs.

Copper oxide/graphitic carbon nitride composite for bisphenol a degradation by boosted peroxymonosulfate activation: Mechanism of Cu-O covalency governs.

Surface structure can govern heterogeneous catalysis, resulting in its critical role in nonradical reactions. Here, we explored whether Cu-O covalency plays a critical role in controlling the inherent properties of copper oxide/graphitic carbon nitride (CuO-CN). Experiments and theoretical calculations show that, in contrast to the traditional concept of low-valent metal control activity, surface modification enlarges Cu-O covalency, and high-valent copper species at the surface easily bind peroxymonosulfate (PMS, (HSO5-)) anions. Therefore, optimized CuO-CN corresponds to a 14.8-fold higher kinetic reaction rate (0.10392 min-1) for PMS activation and pollutant degradation over those of unoptimized CuO-CN. Based on two-dimensional Fourier transform infrared correlation spectroscopy (2D-FT-IR-COS), Cu-O was determined to be the main active site. Cu-O is more active than other groups and acts before other groups. Benefiting from this electron transfer mechanism, CuO-CN shows good environmental tolerance (pH, anions, humic acid and actual water bodies such as tap water and groundwater). The established empirical kinetic model shows a strong linear correlation with the experimental kinetic reaction rate (> 0.94). CuO-CN/PMS can degrade organic pollutants efficiently for up to 30 days in a filter reactor. This work provides an understanding of the key role of the surface electronic structure in the nonradical activation of PMS and may provide support for improving the design of PMS catalysts.

Tailored d-Band Facilitating in Fe Gradient Doping CuO Boosts Peroxymonosulfate Activation for High Efficiency Generation and Release of Singlet Oxygen.

In the field of heterogeneous catalysis, limitations of the surface reaction process inevitably make improving the catalytic efficiency to remove pollutants in water a major challenge. Here, we report a unique structure of Fe surface-gradient-doped CuO that improves the overall catalytic processes of adsorption, electron transfer, and desorption. Interestingly, gradient doping leads to an imbalanced charge distribution in the crystal structure, thereby promoting the adsorption and electron transport efficiency of peroxymonosulfate (PMS). The orbital hybridization of Fe also improves the electronic activity. More importantly, the occupied d-orbital distribution is closer to the lower energy level, which improves the desorption of the reaction intermediate (1O2). As a result, the production and desorption of 1O2 have been improved, resulting in excellent BPA degradation ability (kinetic rate increased by 67.3 times). Two-dimensional infrared correlation spectroscopy is used to better understand the doping process and catalytic mechanism of Fe-CuO. Fe-O changes before Cu-O and is more active. The Fe-required active sites, active species intensity, and kinetic reaction rates show a good correlation. This research provides a scientific basis for expanding the purification of toxic organic pollutants in complex water environments by heterogeneous catalytic oxidation.

Homogeneously high expression of CD32b makes it a potential target for CAR-T therapy for chronic lymphocytic leukemia.

CD19 chimeric antigen receptor (CAR)-T cells have been used to treat patients with refractory chronic lymphocytic leukemia (CLL). However, approximately 50% of patients do not respond to this therapy. To improve the clinical outcome of these patients, it is necessary to develop strategies with other optimal targets to enable secondary or combinational CAR-T cell therapy. By screening a panel of surface antigens, we found that CD32b (FcγRIIb) was homogeneously expressed at high site density on tumor cells from CLL patients. We then developed a second-generation CAR construct targeting CD32b, and T cells transduced with the CD32 CAR efficiently eliminated the CD32b+ Raji leukemic cell line in vitro and in a mouse xenograft model. Furthermore, CD32b CAR-T cells showed cytotoxicity against primary human CLL cells that were cultured in vitro or transplanted into immunodeficient mice. The efficacy of CD32b CAR T cells correlated with the CD32b density on CLL cells. CD32b is not significantly expressed by non-B hematopoietic cells. Our study thus identifies CD32b as a potential target of CAR-T cell therapy for CLL, although further modification of the CAR construct with a safety mechanism may be required to minimize off-target toxicity.

Differentially expressed ZmASR genes associated with chilling tolerance in maize (Zea mays) varieties.

The ABA-stress-ripening (ASR) gene is an abiotic stress-response gene that is widely present in higher plants. The expression of ASR was recently shown to effectively improve plant tolerance to several abiotic stresses. However, the role of ASR during chilling stress in maize (Zea mays L.) is unclear. In this study, we tested two maize varieties under chilling treatment. Our results showed that Jinyu 5 (JY5), a chilling-sensitive variety, had lower maximum PSII efficiency (Fv/Fm) and higher lipid peroxidation levels than Jidan 198 (JD198) under chilling conditions. At the same time, the enzymes superoxide dismutase (SOD) and peroxidase (POD) were more active in JD198 than in JY5 under chilling conditions. In addition, exogenous ABA spray pretreatments enhanced the chilling tolerance of maize, showing results such as increased Fv/Fm ratios, and SOD and POD activity; significantly reduced lipid peroxidation levels and increased expression of ZmASR1 in both JD198 and JY5 under chilling conditions. Moreover, when the ZmASR1 expression levels in the two maize varieties were compared, the chilling-sensitive line JY5 had significantly lower expression in both the leaves and roots than JD198 under chilling stress, indicating that the expression of ZmASR1 is a chilling response option in plants. Furthermore, we overexpressed ZmASR1 in JY5; this resulted in enhanced maize chilling tolerance, which reduced the decreases in Fv/Fm and the malondialdehyde content and enhanced SOD and POD activity. Overall, these results suggest that ZmASR1 expression plays a protective role against chilling stress in plants.

Synthesis of a g-C3N4-Cu2O heterojunction with enhanced visible light photocatalytic activity by PEG.

A g-C3N4-Cu2O was successfully synthesized in the presence of PEG-400 surfactant via a hydrothermal method and high-temperature calcination method. Based on the results of TEM, XPS, EPR, and other techniques, it was verified that a heterojunction was formed. The synthesized g-C3N4-Cu2O show excellent photocatalytic activity and stability was confirmed through cycling experiments, XRD and XPS. At a suitable addition amount, the value of band gap of g-C3N4-Cu2O is reduced to 1.87 eV, the PL intensity decreases effectively, the specific surface area is increased to 12.8114 m2/g, and the photocatalytic degradation rate is increased to 94%. Adding the surfactant PEG-400 in the precursor solutions leads to a reduction in the crystallite size, which can improve the morphology and specific surface area to form abundant heterojunction interfaces as channels for photo-generated carrier separation, and improve its light utilization and quantum efficiency.