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Alternative polyadenylation (APA) is a widespread mechanism of gene regulation that generates mRNA isoforms with alternative 3' untranslated regions (3' UTRs). Our previous study has revealed the global 3' UTR shortening of host mRNAs through APA upon viral infection. However, how the dynamic changes in the APA landscape occur upon viral infection remains largely unknown. Here we further found that, the reduced protein abundance of CPSF6, one of the core 3' processing factors, promotes the usage of proximal poly(A) sites (pPASs) of many immune related genes in macrophages and fibroblasts upon viral infection. Shortening of the 3' UTR of these transcripts may improve their mRNA stability and translation efficiency, leading to the promotion of type I IFN (IFN-I) signalling-based antiviral immune responses. In addition, dysregulated expression of CPSF6 is also observed in many immune related physiological and pathological conditions, especially in various infections and cancers. Thus, the global APA dynamics of immune genes regulated by CPSF6, can fine-tune the antiviral response as well as the responses to other cellular stresses to maintain the tissue homeostasis, which may represent a novel regulatory mechanism for antiviral immunity.
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Poliadenilación , Virosis , Factores de Escisión y Poliadenilación de ARNm , Humanos , Regiones no Traducidas 3'/genética , Regulación hacia Abajo , Inmunidad/genética , Factores de Escisión y Poliadenilación de ARNm/genética , Factores de Escisión y Poliadenilación de ARNm/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Virosis/genética , Ratones , AnimalesRESUMEN
Charge compensation from cationic and anionic redox couples accompanying Na+ (de)intercalation in layered oxide cathodes contributes to high specific capacity. However, the engagement level of different redox couples remains unclear and their relationship with Na+ content is less studied. Here we discover that it is possible to take full advantage of the high-voltage transition metal (TM) redox reaction through low-valence cation substitution to tailor the electronic structure, which involves an increased ratio of Na+ content to available charge transfer number of TMs. Taking NaxCu0.11Ni0.11Fe0.3Mn0.48O2 as the example, the Li+ substitution increases the ratio to facilitate the high-voltage TM redox activity, and further F-ion substitution decreases the covalency of the TM-O bond to relieve structural changes. As a consequence, the final high-entropy Na0.95Li0.07Cu0.11Ni0.11Fe0.3Mn0.41O1.97F0.03 cathode demonstrates â¼29% capacity increase contributed by the high-voltage TMs and exhibits excellent long-term cycling stability due to the improved structural reversibility. This work provides a paradigm for the design of high-energy-density electrodes by simultaneous electronic and crystal structure modulation.
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Na-ion layered oxide cathodes (NaxTMO2, TM = transition metal ion(s)), as an analogue of lithium layered oxide cathodes (such as LiCoO2, LiNixCoyMn1-x-yO2), have received growing attention with the development of Na-ion batteries. However, due to the larger Na+ radius and stronger Na+-Na+ electrostatic repulsion in NaO2 slabs, some undesired phase transitions are observed in NaxTMO2. Herein, we report a high-entropy configuration strategy for NaxTMO2 cathode materials, in which multicomponent TMO2 slabs with enlarged interlayer spacing help strengthen the whole skeleton structure of layered oxides through mitigating Jahn-Teller distortion, Na+/vacancy ordering, and lattice parameter changes. The strengthened skeleton structure with a modulated particle morphology dramatically improves the Na+ transport kinetics and suppresses intragranular fatigue cracks and TM dissolution, thus leading to highly improved performances. Furthermore, the elaborate high-entropy TMO2 slabs enhance the TM-O bonding energy to restrain oxygen release and thermal runaway, benefiting for the improvement of thermal safety.
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Sodium-ion batteries (SIBs) are receiving considerable attention as economic candidates for large-scale energy storage applications. Na3 V2 (PO4 )2 O2 F (NVPF) is intensively regarded as one of the most promising cathode materials for SIBs, due to its high energy density, fast ionic conduction, and robust Na+ -super-ionic conductor (NASICON) framework. However, poor rate capability ascribed to the intrinsically low electronic conductivity severely hinders their practical applications. Here, high-rate and highly reversible Na+ storage in NVPF is realized by optimizing nanostructure and rational porosity construction. Hierarchical porous NVPF hollow nanospheres are designed to modify the issues of inconvenient electrolyte transportation and unfavorable charge transfer behavior faced by solid-structured electrode materials. The individual unique nanosphere is assembled from numerous nanoparticles, which shortens the length of Na+ transport in solid state and thus facilites the Na+ migration. Hollow nanostructure hierarchically porous configuration enables adequate electrolyte penetration, continuous electrolyte supplementation, and facile electrolyte transportation, leading to barrier-free Na+ /e- diffusion and high-rate cycling. In addition, the large electrolyte accessible surface area boosts the charge transfer in the whole electrode. Therefore, the present NVPF demonstrates unprecedented rate capability (85.4 mAh g-1 at 50 C) and long-term cyclability (62.2% capacity retention after 2000 cycles at 20 C).
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Fifteen constituents, including one new lignan (schisandroside E) and one new terpenoid (schisandenoid A) as well as nine known lignans and four known terpenoids, were isolated from Schisandra chinensis leaves. The structures of schisandroside E and schisandenoid A were established by entirely meticulous spectroscopic analysis (NMR, MS, CD, IR and UV). All compounds were tested for cytotoxicity against MGC-803, Caco-2 and Ishikawa cell lines. Some compounds showed strong cytotoxicity against these three cancer cell lines with IC50 <1â µm.
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Lignanos/química , Schisandra/química , Terpenos/química , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antineoplásicos Fitogénicos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Humanos , Lignanos/aislamiento & purificación , Lignanos/farmacología , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Conformación Molecular , Extractos Vegetales/química , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Schisandra/metabolismo , Terpenos/aislamiento & purificación , Terpenos/farmacologíaRESUMEN
Sodium-ion batteries (NIBs), due to the advantages of low cost and relatively high safety, have attracted widespread attention all over the world, making them a promising candidate for large-scale energy storage systems. However, the inherent lower energy density to lithium-ion batteries is the issue that should be further investigated and optimized. Toward the grid-level energy storage applications, designing and discovering appropriate anode materials for NIBs are of great concern. Although many efforts on the improvements and innovations are achieved, several challenges still limit the current requirements of the large-scale application, including low energy/power densities, moderate cycle performance, and the low initial Coulombic efficiency. Advanced nanostructured strategies for anode materials can significantly improve ion or electron transport kinetic performance enhancing the electrochemical properties of battery systems. Herein, this Review intends to provide a comprehensive summary on the progress of nanostructured anode materials for NIBs, where representative examples and corresponding storage mechanisms are discussed. Meanwhile, the potential directions to obtain high-performance anode materials of NIBs are also proposed, which provide references for the further development of advanced anode materials for NIBs.
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A phytochemical investigation on the 70% EtOH extract of the fruit of Acanthpanax senticosus resulted in the isolation of three new triterpenoids, Falcatane C (1), Acasentrioid F (2), Acasentrioid G (3) together with twenty-seven known ones (4-30). Structural elucidation of all the compounds was performed by spectral methods such as 1D or 2D (1H-1H COSY, HSQC, and HMBC), NMR spectroscopy, and high-resolution mass spectrometry. Moreover, all compounds were evaluated for their effects on H2O2-induced neurotoxicity in human neuroblastoma SH-SY5Ycells. Compounds 13 and 15 showed significant neuroprotective impact at a specific concentration, and compounds 1, 3, 5, 9, 11, 13-15, 17, 20-21, 23-25, 27, 29-30 showed moderate neuroprotective effect. The current study suggests that triterpenes in Eleutherococcus senticosus (Rupr.) Harms may play an essential role in the neuroprotective properties.
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The Jahn-Teller effect (JTE) arising from lattice-electron coupling is a fascinating phenomenon that profoundly affects important physical properties in a number of transition-metal compounds. Controlling JT distortions and their corresponding electronic structures is highly desirable to tailor the functionalities of materials. Here, we propose a local coordinate strategy to regulate the JTE through quantifying occupancy in the [Formula: see text] and [Formula: see text] orbitals of Mn and scrutinizing the symmetries of the ligand oxygen atoms in MnO6 octahedra in LiMn2O4 and Li0.5Mn2O4. The effectiveness of such a strategy has been demonstrated by constructing P2-type NaLi x Mn1 - x O2 oxides with different Li/Mn ordering schemes. In addition, this strategy is also tenable for most 3d transition-metal compounds in spinel and perovskite frameworks, indicating the universality of local coordinate strategy and the tunability of the lattice-orbital coupling in transition-metal oxides. This work demonstrates a useful strategy to regulate JT distortion and provides useful guidelines for future design of functional materials with specific physical properties.
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Air sensitivity remains a substantial barrier to the commercialization of sodium (Na)-layered oxides (NLOs). This problem has puzzled the community for decades because of the complexity of interactions between air components and their impact on both bulk and surfaces of NLOs. We show here that water vapor plays a pivotal role in initiating destructive acid and oxidative degradations of NLOs only when coupled with carbon dioxide or oxygen, respectively. Quantification analysis revealed that reducing the defined cation competition coefficient (η), which integrates the effects of ionic potential and sodium content, and increasing the particle size can enhance the resistance to acid attack, whereas using high-potential redox couples can eliminate oxidative degradation. These findings elucidate the underlying air deterioration mechanisms and rationalize the design of air-stable NLOs.
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All-solid-state polymer electrolytes (ASPEs) with excellent processivity are considered one of the most forward-looking materials for large-scale industrialization. However, the contradiction between improving the mechanical strength and accelerating the ionic migration of ASPEs has always been difficult to reconcile. Herein, a rational concept is raised of high-entropy microdomain interlocking ASPEs (HEMI-ASPEs), inspired by entropic elasticity well-known in polymer and biochemical sciences, by introducing newly designed multifunctional ABC miktoarm star terpolymers into polyethylene oxide for the first time. The tailor-made HEMI-ASPEs possess multifunctional polymer chains, which induce themselves to assemble into micro- and nanoscale dynamic interlocking networks with high topological structure entropy. HEMI-ASPEs achieve excellent toughness, considerable ionic conductivity, an appreciable lithium transference number (0.63), and desirable thermal stability (Td > 400 °C) for all-solid-state lithium metal batteries. The Li|HEMI-ASPE-Li|Li symmetrical cell shows a stable Li plating/stripping performance over 4000 h, and a LiFePO4 |HEMI-ASPE-Li|Li full cell exhibits a high capacity retention (≈96%) after 300 cycles. This work contributes an innovative design concept introducing high-entropy supramolecular dynamic networks for ASPEs.
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ETHNOPHARMACOLOGICAL RELEVANCE: Coptis chinensis Franch. (CCF), as an extensively used traditional Chinese medicine, has therapeutic effects on Alzheimer's disease (AD), but its mechanism of action has not yet been elucidated. AIM OF THE STUDY: This study aims to reveal the mechanism of action of CCF via the gut-brain axis, and provide a new strategy for the clinical treatment of AD. MATERIALS AND METHODS: APPswe/PS1ΔE9 mice were used as AD models, and were given CCF extract by intragastric administration. Barnes maze was used to test the therapeutic effect of CCF on the treatment of AD. To reveal the mechanism of action of CCF in the treatment of AD, Vanquish Flex UHPLC-orbitrap fusion lumos mass was chosen to detect endogenous differential metabolite; MetaboAnalyst 5.0 was applied to derive relevant metabolic pathways; similarly, to explore the effects of CCF on the gut-brain axis, Vanquish Flex UPLC-Orbitrap fusion lumos mass was utilized to detect the changes in the content of SCFAs in AD mice after CCF administration; the prototype components and metabolites in CCF were identified by UPLC/ESI/qTOF-MS, then their effects on Bifidobacterium breve were explored. RESULTS: CCF shortened the latency time of AD mice, improved the target quadrant ratio of AD mice, and made the maze roadmap simpler of AD mice; CCF regulated fifteen potential metabolites of AD mice, interestingly, ILA (indole-3-lactic acid) in SCFAs (short-chain fatty acids) was also included; CCF acted on histidine and phenylalanine metabolic pathways of AD mice; CCF increased the contents of acetic acid and ILA in AD mice; magnoflorine, jatrorrhizine, coptisine, groenlandicine, thalifendine, palmatine, berberine, epiberberine, hydroxylated jatrorrhizine, and 3-methoxydemethyleneberberine in CCF were detected in fecal samples of AD mice; magnoflorine, palmatrubine, 13-methylberberine, berberine, coptisine, and palmatine promoted the growth of Bifidobacterium breve. CONCLUSIONS: we have demonstrated that CCF acts on the gut-brain axis by regulating SCFAs to treat AD.
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Enfermedad de Alzheimer , Berberina , Coptis , Medicamentos Herbarios Chinos , Ratones , Animales , Coptis chinensis , Enfermedad de Alzheimer/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Medicina Tradicional ChinaRESUMEN
Reversible lattice oxygen redox reactions offer the potential to enhance energy density and lower battery cathode costs. However, their widespread adoption faces obstacles like substantial voltage hysteresis and poor stability. The current research addresses these challenges by achieving a non-hysteresis, long-term stable oxygen redox reaction in the P3-type Na2/3Cu1/3Mn2/3O2. Here we show this is accomplished by forming spin singlet states during charge and discharge. Detailed analysis, including in-situ X-ray diffraction, shows highly reversible structural changes during cycling. In addition, local CuO6 Jahn-Teller distortions persist throughout, with dynamic Cu-O bond length variations. In-situ hard X-ray absorption and ex-situ soft X-ray absorption study, along with density function theory calculations, reveal two distinct charge compensation mechanisms at approximately 3.66 V and 3.99 V plateaus. Notably, we observe a Zhang-Rice-like singlet state during 3.99 V charging, offering an alternative charge compensation mechanism to stabilize the active oxygen redox reaction.
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The deposition of volatilized Na+ on the surface of the cathode during sintering results in the formation of surface residual alkali (NaOH/Na2 CO3 NaHCO3 ) in layered cathode materials, leading to serious interfacial reactions and performance degradation. This phenomenon is particularly evident in O3-NaNi0.4 Cu0.1 Mn0.4 Ti0.1 O2 (NCMT). In this study, a strategy is proposed to transform waste into treasure by converting residual alkali into a solid electrolyte. Mg(CH3 COO)2 and H3 PO4 are reacted with surface residual alkali to generate the solid electrolyte NaMgPO4 on the surface of NCMT, which can be labeled as NaMgPO4@NaNi0.4 Cu0.1 Mn0.4 Ti0.1 O2 -X (NMP@NCMT-X, where X indicates the different amounts of Mg2+ and PO4 3- ). NaMgPO4 acts as a special ionic conductivity channel on the surface to improve the kinetics of the electrode reactions, remarkably improving the rate capability of the modified cathode at a high current density in the half-cell. Additionally, NMP@NCMT-2 enables a reversible phase transition from the P3 to OP2 phase in the charge-discharge process above 4.2 V and achieves a high specific capacity of 157.3 mAh g-1 and outstanding capacity retention in the full cell. The strategy can effectively and reliably stabilize the interface and improve the performance of layered cathodes for Na-ion batteries (NIBs).
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The preferentially selective extraction of Li+ from spent layered transition metal oxide (LiMO2, M = Ni, Co, Mn, etc.) cathodes has attracted extensive interest based on economic and recycling efficiency requirements. Presently, the efficient recycling of spent LiMO2 is still challenging due to the element loss in multistep processes. Here, we developed a facile strategy to selectively extract Li+ from LiMO2 scraps with stoichiometric H2SO4. The proton exchange reaction could be driven using temperature, accompanied by the generation of soluble Li2SO4 and MOOH precipitates. The extraction mechanism includes a two-stage evolution, including dissolution and ion exchange. As a result, the extraction rate of Li+ is over 98.5% and that of M ions is less than 0.1% for S-NCM. For S-LCO, the selective extraction result is even better. Finally, Li2CO3 products with a purity of 99.68% can be prepared from the Li+-rich leachate, demonstrating lithium recovery efficiencies as high as 95 and 96.3% from NCM scraps and S-LCO scraps, respectively. In the available cases, this work also represents the highest recycling efficiency of lithium, which can be attributed to the high leaching rate and selectivity of Li+, and even demonstrates the lowest reagent cost. The regenerated LiNi0.5Co0.24Mn0.26O2 and Na1.01Li0.001Ni0.38Co0.18Mn0.44O2 cathodes also deliver a decent electrochemical performance for Li-ion batteries (LIBs) and Na-ion batteries (NIBs), respectively. Our current work offers a facile, closed-loop, and scalable strategy for recycling spent LIB cathodes based on the preferentially selective extraction of Li+, which is superior to the other leaching technology in terms of its cost and recycling yield.
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Poly(ethylene oxide)-based solid-state electrolytes are widely considered promising candidates for the next generation of lithium and sodium metal batteries. However, several challenges, including low oxidation resistance and low cation transference number, hinder poly(ethylene oxide)-based electrolytes for broad applications. To circumvent these issues, here, we propose the design, synthesis and application of a fluoropolymer, i.e., poly(2,2,2-trifluoroethyl methacrylate). This polymer, when introduced into a poly(ethylene oxide)-based solid electrolyte, improves the electrochemical window stability and transference number. Via multiple physicochemical and theoretical characterizations, we identify the presence of tailored supramolecular bonds and peculiar morphological structures as the main factors responsible for the improved electrochemical performances. The polymeric solid electrolyte is also investigated in full lithium and sodium metal lab-scale cells. Interestingly, when tested in a single-layer pouch cell configuration in combination with a Li metal negative electrode and a LiMn0.6Fe0.4PO4-based positive electrode, the polymeric solid-state electrolyte enables 200 cycles at 42 mA·g-1 and 70 °C with a stable discharge capacity of approximately 2.5 mAh when an external pressure of 0.28 MPa is applied.
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The operation of lithium-ion batteries involves electron removal from and filling into the redox orbitals of cathode materials, experimentally probing the orbital electron population thus is highly desirable to resolve the redox processes and charge compensation mechanism. Here, we combine quantitative convergent-beam electron diffraction with high-energy synchrotron powder X-ray diffraction to quantify the orbital populations of Co and O in the archetypal cathode material LiCoO2. The results indicate that removing Li ions from LiCoO2 decreases Co t2g orbital population, and the intensified covalency of Co-O bond upon delithiation enables charge transfer from O 2p orbital to Co eg orbital, leading to increased Co eg orbital population and oxygen oxidation. Theoretical calculations verify these experimental findings, which not only provide an intuitive picture of the redox reaction process in real space, but also offer a guidance for designing high-capacity electrodes by mediating the covalency of the TM-O interactions.
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The oxygen redox (OR) activity is conventionally considered detrimental to the stability and kinetics of batteries. However, OR reactions are often confused by irreversible oxygen oxidation. Here, based on high-efficiency mapping of resonant inelastic x-ray scattering of both the transition metal and oxygen, we distinguish the lattice OR in Na0.6[Li0.2Mn0.8]O2 and compare it with Na2/3[Mg1/3Mn2/3]O2. Both systems display strong lattice OR activities but with distinct electrochemical stability. The comparison shows that the substantial capacity drop in Na0.6[Li0.2Mn0.8]O2 stems from non-lattice oxygen oxidations, and its voltage decay from an increasing Mn redox contribution upon cycling, contrasting those in Na2/3[Mg1/3Mn2/3]O2. We conclude that lattice OR is not the ringleader of the stability issue. Instead, irreversible oxygen oxidation and the changing cationic reactions lead to the capacity and voltage fade. We argue that lattice OR and other oxygen activities should/could be studied and treated separately to achieve viable OR-based electrodes.
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Stimuli-responsive nanocarriers for anticancer drug and gene co-delivery are promising strategy in cancer therapy. The ultimate goal is to deliver high local concentration of therapeutic agents with no premature release and result in synergistic effects for combination therapies. In this work, we developed a redox stimuli-responsive and synergistic co-delivery system for anticancer drug DOX and p53 gene for potential cancer therapy. A dendronized chitosan derivative (CP) as a "gatekeeper" to control release the drug was used to modify MSNs via a disulfide linker and improve the gene transfection efficiency. Stimulus-induced release of the DOX was studied in the presence of glutathione (GSH), which showed that polymer shell was shed and accelerated the release of embedded drugs inside the tumor cells under a GSH-rich environment. The obtained nanoparticles showed good gene delivery ability in vitro by inducing an obvious increase in p53 protein expression in Hela cells. Apoptosis analysis confirmed that DOX and p53 could be co-delivered to the Hela cells by MSN-SS-CP nanocarriers and induced significant cell apoptosis. These results demonstrated that the dual delivery system resulted in synergistic effects and lead to an effective cancer cell apoptosis, which may be promising for cancer therapeutic application.
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Antineoplásicos/farmacología , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos/métodos , Técnicas de Transferencia de Gen , Nanopartículas/química , Proteína p53 Supresora de Tumor/farmacología , Antineoplásicos/metabolismo , Apoptosis/efectos de los fármacos , Quitosano/química , Doxorrubicina/metabolismo , Composición de Medicamentos/métodos , Liberación de Fármacos , Sinergismo Farmacológico , Glutatión/química , Células HeLa , Humanos , Concentración de Iones de Hidrógeno , Cinética , Nanopartículas/ultraestructura , Oxidación-Reducción , Porosidad , Dióxido de Silicio/química , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Nanotechnology and carbon coating have been applied to silicon anodes to achieve excellent lithium-ion batteries, but the exclusive influence of carbon coating on solid-electrolyte interphase (SEI) formation is difficult to exhibit distinctly because of the impurity and morphological irregularity of most nanostructured anodes. Here, we design a silicon nanocone-carbon (SNC-C) composite structure as a model anode to demonstrate the significant influences of carbon coating on SEI formation and electrochemical performance, unaffectedly as a result of pure electrode component and distinctly due to regular nanocone morphology. As demonstrated by morphological and elemental analysis, compared to the SNC electrode, the SNC-C electrode maintains a thinner SEI layer (â¼10 nm) and more stable structure during cycling as well as longer cycle life (>725 cycles), higher Coulombic efficiency (>99%), and lower electrode polarization. This well-defined structure clearly shows the interface stability attributed to carbon coating and is promising in fundamental research of the silicon anode.