Summary
Nitrogen (N) is one of the key essential macronutrients that affects rice growth and yield. Inorganic N fertilizers are excessively used to boost yield and generate serious collateral ...environmental pollution. Therefore, improving crop N use efficiency (NUE) is highly desirable and has been a major endeavour in crop improvement. However, only a few regulators have been identified that can be used to improve NUE in rice to date. Here we show that the rice NIN‐like protein 4 (OsNLP4) significantly improves the rice NUE and yield. Field trials consistently showed that loss‐of‐OsNLP4 dramatically reduced yield and NUE compared with wild type under different N regimes. In contrast, the OsNLP4 overexpression lines remarkably increased yield by 30% and NUE by 47% under moderate N level compared with wild type. Transcriptomic analyses revealed that OsNLP4 orchestrates the expression of a majority of known N uptake, assimilation and signalling genes by directly binding to the nitrate‐responsive cis‐element in their promoters to regulate their expression. Moreover, overexpression of OsNLP4 can recover the phenotype of Arabidopsis nlp7 mutant and enhance its biomass. Our results demonstrate that OsNLP4 plays a pivotal role in rice NUE and sheds light on crop NUE improvement.
Formation of surface passivation layer is a major problem that restricts the potential of aluminum (Al)-H2O system for hydrogen source applications. Several reaction-promoting approaches have been ...developed, but most of them are costly. Herein, we report a simple yet highly effective method for improving the reactivity of Al with alkaline solution. Our study found that mechanically milling Al powder with the cheap and readily available activated charcoal (AC) for short periods of time could significantly improve the hydrogen generation kinetics of Al-H2O system, to a level far exceeding that of the systems with oxide or salt promoters. For instance, the 15 min-milled Al/AC composite with a mass ratio of 5:1 could fulfill a 98% fuel conversion within ∼1 min in a 1 M NaOH solution, and its maximal hydrogen generation rate reached up to 4556 mL min−1 g−1, which was over 18-fold faster than that of Al powder. A favorable combination of low material cost, simple preparation process and fairly good H2 generation performance makes the thus-constituted Al/AC-H2O system promising for mobile and portable applications. The promoting effect of AC additive on Al-H2O reaction kinetics was discussed based on the microstructure characterization and control experiments.
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•Milled Al/AC composite could rapidly react with alkaline solution to generate hydrogen.•AC is superior to oxide or salt promoters in improving Al-H2O reaction kinetics.•Low cost, simple preparation and good reaction kinetics make Al/AC-H2O promising for practical applications.
Neuroinflammation, especially innate immunocyte-mediated neuroinflammation, has been reported to participate in pathogenesis of Alzheimer's disease (AD). However, the involvement of adaptive immune ...cells, such as CD4(+) T lymphocytes, in pathogenesis of AD is not well clarified. Herein, we focus on T helper 17 (Th17) cells, a subpopulation of CD4(+) T cells with high proinflammation, and show the implication of the cells in neurodegeneration of AD. Amyloid β1-42 (Aβ1-42) was bilaterally injected into hippocampus of rats to induce AD. On days 7 and 14 following the Aβ1-42 administration, escape latency of the rats in Morris water maze was increased, expression of amyloid precursor protein was upregulated, but expression of protein phosphatase 2A was downregulated in the hippocampus, and Nissl stain showed neuronal loss and gliosis in CA1 region. Infusion of FITC-linked albumin in blood circulation and combination with immunostaining of hippocampal sections for RORγ, a specific transcriptional factor of Th17 cells, demonstrated blood-brain barrier (BBB) disruption and Th17 cells' infiltration into brain parenchyma of AD rats. Expression of Th17 proinflammatory cytokines, interleukin (IL)-17 and IL-22, was increased in the hippocampus, and concentrations of the two cytokines were elevated in both the cerebrospinal fluid and the serum in AD occurrence and development. Compared with intact or saline-treated control rats, AD animals indicated an upregulated expression of Fas and FasL in the hippocampus. Further, the immunofluorescent histochemistry on AD hippocampal sections with NeuN, RORγ, Fas and FasL displayed that Fas was principally expressed by neurons and FasL was predominantly expressed by Th17 cells, and that neuronal apoptosis shown by TUNEL and NeuN double-labeled cells increased. These results suggest that Th17 cells, which were infiltrated into AD brain parenchyma, participate in neuroinflammation and neurodegeneration of AD by release of proinflammatory cytokines and by direct action on neurons via Fas/FasL apoptotic pathway.
Neuroinflammation has been reported to be associated with Alzheimer's disease (AD) pathogenesis. Neuroinflammation is generally considered as an outcome of glial activation; however, we recently ...demonstrated that T helper (Th)17 cells, a subpopulation of proinflammatory CD4+ T cells, are also involved in AD pathogenesis. Transforming growth factor (TGF)-β1, a cytokine that can be expressed in the brain, can be immunosuppressive, but its effects on lymphocyte-mediated neuroinflammation in AD pathogenesis have not been well addressed. In the current study we administered TGF-β1 via intracerebroventricle (ICV) and intranasal (IN) routes in AD model rats to investigate its antiinflammatory and neuroprotective effects. The AD rat model was prepared by bilateral hippocampal injection of amyloid-β (Aβ)1-42. TGF-β1 was administered via ICV one hour prior to Aβ1-42 injection or via both nares seven days after Aβ1-42 injection. ICV administration of TGF-β1 before Aβ1-42 injection remarkably ameliorated Aβ1-42-induced neurodegeneration and prevented Aβ1-42-induced increases in glia-derived proinflammatory mediators (TNF-α, IL-1β and iNOS), as well as T cell-derived proinflammatory cytokines (IFN-γ, IL-2, IL-17 and IL-22), in the hypothalamus, serum or cerebrospinal fluid (CSF) in a concentration-dependent manner. TGF-β1 pretreatment also prevented Aβ1-42-induced decreases in the neurotrophic factors, IGF-1, GDNF and BDNF, and in the antiinflammatory cytokine, IL-10. Similarly, IN administration of TGF-β1 after Aβ1-42 injection reduced neurodegeneration, elevation of proinflammatory mediators and cytokines, and reduction of neurotrophic and antiinflammatory factors, in the hypothalamus, serum or CSF. These findings suggest that TGF-β1 suppresses glial and T cell-mediated neuroinflammation and thereby alleviates AD-related neurodegeneration. The effectiveness of IN administered TGF-β1 in reducing Aβ1-42 neurotoxicity suggests a possible therapeutic approach in patients with AD.
Nitrogen (N) is an essential macronutrient for crop growth and yield. Improving the N use efficiency (NUE) of crops is important to agriculture. However, the molecular mechanisms underlying NUE ...regulation remain largely elusive. Here we report that the OsNLP3 (NIN‐like protein 3) regulates NUE and grain yield in rice under N sufficient conditions. OsNLP3 transcript level is significantly induced by N starvation and its protein nucleocytosolic shuttling is specifically regulated by nitrate. Loss‐of‐function of OsNLP3 reduces plant growth, grain yield, and NUE under sufficient nitrate conditions, whereas under low nitrate or different ammonium conditions, osnlp3 mutants show no clear difference from the wild type. Importantly, under sufficient N conditions in the field, OsNLP3 overexpression lines display improved grain yield and NUE compared with the wild type. OsNLP3 orchestrates the expression of multiple N uptake and assimilation genes by directly binding to the nitrate‐responsive cis‐elements in their promoters. Overall, our study demonstrates that OsNLP3, together with OsNLP1 and OsNLP4, plays overlapping and differential roles in N acquisition and NUE, and modulates NUE and the grain yield increase promoted by N fertilizer. Therefore, OsNLP3 is a promising candidate gene for the genetic improvement of grain yield and NUE in rice.
Summary Statement
Crop nitrogen use efficiency (NUE) is an important agronomic trait. But the molecular mechanisms underlying NUE regulation are not well understood. This study reveals that rice NIN‐like protein 3 (OsNLP3) regulates NUE and grain yield especially under N sufficient conditions and is a promising candidate gene for improving grain yield and NUE in rice.
Supported alloy catalysts play a pivotal role in many heterogeneous catalytic processes of socioeconomic and environmental importance. But the controlled synthesis of supported alloy nanoparticles ...with consistent composition and tight size distribution remains a challenging issue. Herein, a simple yet effective method for preparation of highly dispersed, homogeneously alloyed bimetallic nanoparticles on oxide supports is reported. This method is based on solid solution of metal cations in parent oxide and strong electrostatic adsorption of a secondary metal species onto the oxide surface. In the reductive annealing process, hydrogen spillover occurs from the surface metal with a higher reduction potential to the solute metal in solid solution, leading to metal exsolution and homogenous alloying of the metals on the oxide surface. The ceria‐supported Ni–Pt alloy is chosen as a model catalyst and hydrazine monohydrate decomposition is chosen as a probe reaction to demonstrate this method, and particularly its advantages over the conventional impregnation and galvanic replacement methods. A systematic application of this method using different oxides and base‐noble metal pairs further elucidates its applicability and generality.
Highly dispersed and well‐alloyed bimetallic nanoparticles on oxide support can be readily synthesized by a simple method based on solid solution and strong electrostatic adsorption. Given the variety of solid solutions and universality of strong electrostatic adsorption, this method may find broad applications in the synthesis of advanced supported alloy catalysts for heterogeneous catalysis.
T helper (Th)17 cells, a subset of CD4
+
T lymphocytes, have strong pro-inflammatory property and appear to be essential in the pathogenesis of many inflammatory diseases. However, the involvement of ...Th17 cells in Parkinson’s disease (PD) that is characterized by a progressive degeneration of dopaminergic (DAergic) neurons in the nigrostriatal system is unclear. Here, we aimed to demonstrate that Th17 cells infiltrate into the brain parenchyma and induce neuroinflammation and DAergic neuronal death in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)- or 1-methyl-4-phenylpyridinium (MPP
+
)-induced PD models. Blood–brain barrier (BBB) disruption in the substantia nigra (SN) was assessed by the signal of FITC-labeled albumin that was injected into blood circulation via the ascending aorta. Live cell imaging system was used to observe a direct contact of Th17 cells with neurons by staining these cells using the two adhesion molecules, leukocyte function-associated antigen (LFA)-1 and intercellular adhesion molecule (ICAM)-1, respectively. Th17 cells invaded into the SN where BBB was disrupted in MPTP-induced PD mice. Th17 cells exacerbated DAergic neuronal loss and pro-inflammatory/neurotrophic factor disorders in MPP
+
-treated ventral mesencephalic (VM) cell cultures. A direct contact of LFA-1-stained Th17 cells with ICAM-1-stained VM neurons was dynamically captured. Either blocking LFA-1 in Th17 cells or blocking ICAM-1 in VM neurons with neutralizing antibodies abolished Th17-induced DAergic neuronal death. These results establish that Th17 cells infiltrate into the brain parenchyma of PD mice through lesioned BBB and exert neurotoxic property by promoting glial activation and importantly by a direct damage to neurons depending on LFA-1/ICAM-1 interaction.
Selective decomposition of hydrous hydrazine (N2H4⋅H2O) over metal catalysts provides a promising means for onboard or portable hydrogen source applications. Studies on N2H4⋅H2O decomposition ...catalysts mainly focus on the effects of bulk composition and structure on their performances, instead of the surface‐composition‐dependent properties. Herein, the synthesis of an Ir‐modified Ni/meso‐CeO2 catalyst is reported by using a combination of colloidal solution combustion synthesis and galvanic replacement methods. A combination of structural characterization, control experiments, and DFT calculations reveals that the Ni−Ir alloy resulting from calcination treatment exerts a profound effect on the catalytic properties. The resulting Ni@Ni−Ir/meso‐CeO2 catalyst shows excellent catalytic performance towards hydrogen generation from N2H4⋅H2O, which compares favorably with the Ni−Ir bimetallic catalysts reported to date.
Are two metals better than one? Surface modification of a Ni nanocatalyst by Ir results in remarkably improved catalytic properties towards H2 generation from N2H4⋅H2O. Coupled experimental and theoretical studies reveal that the formation of Ni−Ir alloy on the catalyst surface plays a crucial role in determining the catalytic performance (see figure).
The successful treatment of infected wounds requires strategies with effective antimicrobial, anti-inflammatory, and healing-promoting properties. Accordingly, the use of Cu2+ and tetracycline (TC), ...which can promote angiogenesis, re-epithelialization, and collagen deposition, also antibacterial activity, at the wound site, has shown application prospects in promoting infected wound repair. However, realizing controllable release to prolong action time and avoid potential toxicities is critical. Moreover, near-infrared light (NIR)-activated mesoporous polydopamine nanoparticles (MPDA NPs) reportedly exert anti-inflammatory effects by eliminating the reactive oxygen species generated during inflammatory responses. In this study, we assess whether Cu2+ and TC loaded in MPDA NPs can accelerate infected wound healing in mice. In particular, Cu2+ is chelated and immobilized on the surface of MPDA NPs, while a thermosensitive phase-change material (PCM; melting point: 39–40 °C), combined with antibiotics, was loaded into the MPDA NPs as a gatekeeper (PPMD@Cu/TC). Results show that PPMD@Cu/TC exhibits significant great photothermal properties with NIR irradiation, which induces the release of Cu2+, while inducing PCM melting and, subsequent, TC release. In combination with anti-inflammatory therapy, NIR-triggered Cu2+ and TC release enables the nanocomposite to eradicate bacterial wound infections and accelerate healing. Importantly, negligible damage to primary organs and satisfactory biocompatibility were observed in the murine model. Collectively, these findings highlight the therapeutic potential of this MPDA-based platform for controlling bacterial infection and accelerating wound healing.
Spatial source phase, the phase information of spatial maps extracted from functional magnetic resonance imaging (fMRI) data by data‐driven methods such as independent component analysis (ICA), has ...rarely been studied. While the observed phase has been shown to convey unique brain information, the role of spatial source phase in representing the intrinsic activity of the brain is yet not clear. This study explores the spatial source phase for identifying spatial differences between patients with schizophrenia (SZs) and healthy controls (HCs) using complex‐valued resting‐state fMRI data from 82 individuals. ICA is first applied to preprocess fMRI data, and post‐ICA phase de‐ambiguity and denoising are then performed. The ability of spatial source phase to characterize spatial differences is examined by the homogeneity of variance test (voxel‐wise F‐test) with false discovery rate correction. Resampling techniques are performed to ensure that the observations are significant and reliable. We focus on two components of interest widely used in analyzing SZs, including the default mode network (DMN) and auditory cortex. Results show that the spatial source phase exhibits more significant variance changes and higher sensitivity to the spatial differences between SZs and HCs in the anterior areas of DMN and the left auditory cortex, compared to the magnitude of spatial activations. Our findings show that the spatial source phase can potentially serve as a new brain imaging biomarker and provide a novel perspective on differences in SZs compared to HCs, consistent with but extending previous work showing increased variability in patient data.
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