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1.
Cell Mol Life Sci ; 81(1): 398, 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39261317

RESUMEN

BACKGROUND: Abnormal lipid deposition is an important driver of the progression of metabolic dysfunction-associated steatotic liver disease (MASLD). MicroRNA-411-5p (miR-411-5p) and eukaryotic translation initiation factor 4γ2 (EIF4G2) are related to abnormal lipid deposition, but the specific mechanism is unknown. METHODS: A high-fat, high-cholesterol diet (HFHCD) and a choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) and a high-fructose diet (HFrD) were used to establish MASLD rat and mouse models, respectively. MiR-411-5p agomir and mimic were used to upregulate the miR-411-5p in vivo and in vitro, respectively. Adeno-associated virus type 8 (AAV8) carrying EIF4G2 short hairpin RNA (shRNA) and small interfering RNA (siRNA) were used to downregulate the EIF4G2 expression in vivo and in vitro, respectively. Liver histopathological analysis, Biochemical analysis and other experiments were used to explore the functions of miR-411-5p and EIF4G2. RESULTS: MiR-411-5p was decreased in both MASLD rats and mice, and was negatively correlated with liver triglycerides and serum alanine transaminase (ALT) and aspartate transaminase (AST) levels. Upregulation of miR-411-5p alleviated liver lipid deposition and hepatocellular steatosis. Moreover, miR-411-5p targeted and downregulated EIF4G2. Downregulation of EIF4G2 not only reduced liver triglycerides and serum ALT and AST levels in MASLD model, but also alleviated lipid deposition. Notably, upregulation of miR-411-5p and downregulation of EIF4G2 led to the reduction of forkhead box class O3 (FOXO3) and inhibited the expression of sterol regulatory-element binding protein 1 (SREBP1), acetyl-CoA carboxylase 1 (ACC1) and fatty acid synthase (FASN), thereby reducing fatty acid synthesis. CONCLUSIONS: Upregulation of miR-411-5p inhibits EIF4G2 to reduce the FOXO3 expression, thereby reducing fatty acid synthesis and alleviating abnormal lipid deposition in MASLD.


Asunto(s)
Proteína Forkhead Box O3 , Metabolismo de los Lípidos , MicroARNs , Animales , MicroARNs/genética , MicroARNs/metabolismo , Ratones , Masculino , Ratas , Metabolismo de los Lípidos/genética , Proteína Forkhead Box O3/metabolismo , Proteína Forkhead Box O3/genética , Factor 4G Eucariótico de Iniciación/metabolismo , Factor 4G Eucariótico de Iniciación/genética , Ratones Endogámicos C57BL , Humanos , Hígado Graso/metabolismo , Hígado Graso/patología , Hígado Graso/genética , Dieta Alta en Grasa/efectos adversos , Modelos Animales de Enfermedad , Ratas Sprague-Dawley , Hígado/metabolismo , Hígado/patología
2.
Nano Lett ; 24(11): 3462-3469, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38451166

RESUMEN

Two-dimensional (2D) room-temperature multiferroic materials are highly desirable but still very limited. Herein, we propose a potential strategy to obtain such materials in 2D metal-organic frameworks (MOFs) by utilizing the d-p direct spin coupling in conjunction with center-symmetry-breaking six-membered heterocyclic rings. Based on this strategy, a screening of 128 2D MOFs results in the identification of three multiferroics, that is, Cr(1,2-oxazine)2, Cr(1,2,4-triazine)2, and Cr(1,2,3,4-trazine)2, simultaneously exhibiting room-temperature ferrimagnetism and ferroelectricity/antiferroelectricity. The room-temperature ferrimagnetic order (306-495 K) in these MOFs originates from the strong d-p direct magnetic exchange interaction between Cr cations and ligand anions. Specifically, Cr(1,2-oxazine)2 exhibits ferroelectric behavior with an out-of-plane polarization of 4.24 pC/m, whereas the other two manifest antiferroelectric characteristics. Notably, all three materials present suitable polarization switching barriers (0.18-0.31 eV). Furthermore, these MOFs are all bipolar magnetic semiconductors with moderate band gaps, in which the spin direction of carriers can be manipulated by electrical gating.

3.
Angew Chem Int Ed Engl ; 63(19): e202316717, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38477147

RESUMEN

The electrolytes for lithium metal batteries (LMBs) are plagued by a low Li+ transference number (T+) of conventional lithium salts and inability to form a stable solid electrolyte interphase (SEI). Here, we synthesized a self-folded lithium salt, lithium 2-[2-(2-methoxy ethoxy)ethoxy]ethanesulfonyl(trifluoromethanesulfonyl) imide (LiETFSI), and comparatively studied with its structure analogue, lithium 1,1,1-trifluoro-N-[2-[2-(2-methoxyethoxy)ethoxy)]ethyl]methanesulfonamide (LiFEA). The special anion chemistry imparts the following new characteristics: i) In both LiFEA and LiETFSI, the ethylene oxide moiety efficiently captures Li+, resulting in a self-folded structure and high T+ around 0.8. ii) For LiFEA, a Li-N bond (2.069 Å) is revealed by single crystal X-ray diffraction, indicating that the FEA anion possesses a high donor number (DN) and thus an intensive interphase "self-cleaning" function for an ultra-thin and compact SEI. iii) Starting from LiFEA, an electron-withdrawing sulfone group is introduced near the N atom. The distance of Li-N is tuned from 2.069 Šin LiFEA to 4.367 Šin LiETFSI. This alteration enhances ionic separation, achieves a more balanced DN, and tunes the self-cleaning intensity for a reinforced SEI. Consequently, the fast charging/discharging capability of LMBs is progressively improved. This rationally tuned anion chemistry reshapes the interactions among Li+, anions, and solvents, presenting new prospects for advanced LMBs.

4.
ACS Omega ; 9(6): 7163-7172, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38371816

RESUMEN

In the InGaN multiple quantum wells (MQWs), V-shaped pits play a crucial role in carrier transport, which directly affects emitting efficiency. First-principles calculations are applied to investigate the formation of the V-shaped pits, and the results indicate that they are inclined to form in the N-rich environment. Meanwhile, we calculate the interfacial electronic properties of the sidewalls of the V-shaped pits with varying indium (In) and magnesium (Mg) compositions. The calculated valence band offset (VBO) of the In0.3Ga0.7N/Ga0.94Mg0.06N (0001) is 0.498 eV, while that of the In0.07Ga0.93N/Ga0.94Mg0.06N (101̅1) is 0.340 eV. The band alignment results show that the valence band edges in the Ga1-yMgyN layer are in higher energy than in the InxGa1-xN layer. These are in good agreement with the values reported in the previous numerical simulation. Moreover, the calculation of the projected density of states (PDOS) of interfaces discloses that the strong hybridization between the N 2p orbital and the Mg 2p orbital exerts a vital influence on the upward shifts of the valence band edges in the superlattices (SLs). All these results reveal that holes are easier to inject into the quantum wells (QWs) via the sidewall of V-shaped pits rather than the c-plane QWs, providing a theoretical basis for the growth of InGaN MQWs samples containing V-shaped pits.

5.
Nat Nanotechnol ; 19(3): 387-398, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38052943

RESUMEN

Trained immunity enhances the responsiveness of immune cells to subsequent infections or vaccinations. Here we demonstrate that pre-vaccination with bacteria-derived outer-membrane vesicles, which contain large amounts of pathogen-associated molecular patterns, can be used to potentiate, and enhance, tumour vaccination by trained immunity. Intraperitoneal administration of these outer-membrane vesicles to mice activates inflammasome signalling pathways and induces interleukin-1ß secretion. The elevated interleukin-1ß increases the generation of antigen-presenting cell progenitors. This results in increased immune response when tumour antigens are delivered, and increases tumour-antigen-specific T-cell activation. This trained immunity increased protection from tumour challenge in two distinct cancer models.


Asunto(s)
Neoplasias , Inmunidad Entrenada , Animales , Ratones , Interleucina-1beta , Vacunación , Neoplasias/prevención & control , Activación de Linfocitos , Antígenos de Neoplasias , Bacterias
6.
Phys Chem Chem Phys ; 25(40): 27774-27782, 2023 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-37814799

RESUMEN

Improving the luminescence efficiency of InGaN-based long wavelength LEDs for use in micro-LED full-colour displays remains a huge challenge. The strain-induced piezoelectric effect is an effective measure for modulating the carrier redistribution at the InGaN/GaN heterointerfaces. Our theoretical results reveal that the hole injection is significantly improved by the diminution of the valence band offset (VBO) of the InGaN/GaN heterointerfaces along the [0001] direction, and inversely, the VBO increases along the [0001] direction. The energy band structures showed that the tensile strain of the GaN film grown on a silicon (Si) substrate could weaken the internal electric field of the InGaN well layer leading to a flattening of the energy band, which increases the overlap of electron and hole wave functions. In addition, the strain-induced piezoelectric polarisation of the InGaN layer on the Si substrate generates opposite sheet-bound charges at the heterointerfaces, which causes a reduction in the depletion region of the InGaN/GaN quantum wells (QWs). A systematic analysis illustrates that the control of the piezoelectric polarisation of the InGaN QW layer is available improve the internal quantum efficiency of the InGaN-based LEDs.

7.
Adv Mater ; 35(46): e2306158, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37643537

RESUMEN

Trained immunity refers to the innate immune system building memory-like features in response to subsequent infections and vaccinations. Compared with classical tumor vaccines, trained immunity-related vaccines (TIrV) are independent of tumor-specific antigens. Bacterial outer membrane vesicles (OMVs) contain an abundance of PAMPs and have the potential to act as TIrV-inducer, but face challenges in endotoxin tolerance, systemic delivery, long-term training, and trained tumor-associated macrophage (TAM)-mediated antitumor phagocytosis. Here, an OMV-based TIrV is developed, OMV nanohybrids (OMV-SIRPα@CaP/GM-CSF) for exerting vaccine-enhanced antitumor activity. In the bone marrow, GM-CSF-assisted OMVs train bone marrow progenitor cells and monocytes, which are inherited by TAMs. In tumor tissues, SIRPα-Fc-assisted OMVs trigger TAM-mediated phagocytosis. This TIrV can be identified by metabolic and epigenetic rewiring using transposase-accessible chromatin (ATAC) and transcriptome sequencing. Furthermore, it is found that the TIrV-mediated antitumor mechanism in the MC38 tumor model (TAM-hot and T cell-cold) is trained immunity and activated T cell response, whereas in the B16-F10 tumor model (T cell-hot and TAM-cold) is primarily mediated by trained immunity. This study not only develops and identifies OMV-based TIrV, but also investigates the trained immunity signatures and therapeutic mechanisms, providing a basis for further vaccination strategies.


Asunto(s)
Vacunas contra el Cáncer , Vesículas Extracelulares , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Inmunidad Entrenada , Macrófagos Asociados a Tumores
8.
Talanta ; 265: 124887, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37429255

RESUMEN

Detection abilities on tested subjects of sensors should be closely connected to the sensing unit numbers. Herein, two anion sensors ICZ-o-1S and ICZ-o-2S were synthesized by using indolo (2,3-a) carbazoles as fluorescent chromophore and salicylaldehyde as recognition site. Though UV-Vis and fluorescent ways, it demonstrated that F- can induce the sensor solutions becoming colored from colorless to yellow green, and can endow them with bright green turn-on fluorescence, proving their sensitive and selective sensing on F-. Accordingly, the F ion sensing studies including anti-interference abilities against to other anions on fluorescence response, stoichiometric ratios of sensor-F- in 1 : 1 and 1 : 2, -OH deprotonation sensing mechanism confirmed by 1H NMR titration and theoretical calculation were fully covered. Most importantly, fluoride ion detection limits achieved by ICZ-o-1S and ICZ-o-2S were 1.8 × 10-7 M and 6.0 × 10-8 M, respectively, the latter with two sensing units exhibited 3 times lower detection limit outcompeted to the former with only one sensing unit, rendering the sensor design strategy of improving detecting ability by increasing sensing unit number was rational. The practical application of F- detection in water-containing environment calibrated from the standard curve between the fluorescence intensity of sensor-F- system and the changing F- concentration was conducted. In addition, the accuracy of the sensor on detecting F- was evaluated by the spiked recovery experiment, therefore, the fast and convenient F- concentration detection based on the fluorescence color RGB values of the tested sensor-sample mixture was investigated. Consequently, the results obtained by these two sensors should deliver effective supports on designing high-performance sensors featuring naked-eye and fluorescence turn-on anion sensing by altering the response unit numbers.

10.
J Phys Chem Lett ; 14(21): 5048-5054, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37227122

RESUMEN

Cluster-assembled materials are of considerable interest owing to their unique properties and extensive application prospects. Nevertheless, the majority of cluster-assembled materials developed to date are nonmagnetic, limiting their applications in spintronics. Thus, two-dimensional (2D) cluster-assembled sheets with intrinsic ferromagnetism are very desirable. Here, via first-principles calculations, utilizing the recently synthesized magnetic superatomic cluster [Fe6S8(CN)6]5- as a building block, we design a series of thermodynamically stable 2D nanosheets [NH4]3[Fe6S8(CN)6]TM (TM = Cr, Mn, Fe, Co) with robust ferromagnetic ordering (Curie temperatures (Tc) up to 130 K), medium band gaps (from 1.96 to 2.01 eV), and sizable magnetic anisotropy energy (up to 0.58 meV per unit cell). Among these nanosheets, the [NH4]3[Fe6S8(CN)6]Cr is a bipolar magnetic semiconductor, whereas the other three ([NH4]3[Fe6S8(CN)6]TM (TM = Mn, Fe, Co) are half semiconductors. Additionally, the electronic and magnetic properties of [NH4]3[Fe6S8(CN)6]TM (TM = Cr, Mn, Fe, Co) nanosheets can be easily modulated by electron and hole doping via simply controlling the number of ammonium counterions. Furthermore, the Curie temperatures of the 2D nanosheets can be improved to 225 and 327 K by choosing 4d/5d transition metals TM = Ru and Os, respectively.

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