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1.
Proc Natl Acad Sci U S A ; 120(52): e2317174120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38127984

RESUMO

Converting spent lithium-ion batteries (LIBs) and industrial wastewater into high-value-added substances by advanced electrocatalytic technology is important for sustainable energy development and environmental protection. Here, we propose a self-powered system using a home-made sulfide fuel cell (SFC) to power a two-electrode electrocatalytic sulfion oxidation reaction (SOR)-assisted hydrogen (H2) production electrolyzer (ESHPE), in which the sulfion-containing wastewater is used as the liquid fuel to produce clean water, sulfur, and hydrogen. The catalysts for the self-powered system are mainly prepared from spent LIBs to reduce the cost, such as the bifunctional Co9S8 catalyst was prepared from spent LiCoO2 for SOR and hydrogen evolution reaction (HER). The Fe-N-P codoped coral-like carbon nanotube arrays encapsulated Fe2P (C-ZIF/sLFP) catalyst was prepared from spent LiFePO4 for oxygen reduction reaction. The Co9S8 catalyst shows excellent catalytic activities in both SOR and HER, evidenced by the low cell voltage of 0.426 V at 20 mA cm-2 in ESHPE. The SFC with Co9S8 as anode and C-ZIF/sLFP as cathode exhibits an open-circuit voltage of 0.69 V and long discharge stability for 300 h at 20 mA cm-2. By integrating the SFC and ESHPE, the self-powered system delivers an impressive hydrogen production rate of 0.44 mL cm-2 min-1. This work constructs a self-powered system with high-performance catalysts prepared from spent LIBs to transform sulfion-containing wastewater into purified water and prepare hydrogen, which is promising to achieve high economic efficiency, environmental remediation, and sustainable development.

2.
Proc Natl Acad Sci U S A ; 120(15): e2300197120, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37018192

RESUMO

Composite-polymer-electrolytes (CPEs) embedded with advanced filler materials offer great promise for fast and preferential Li+ conduction. The filler surface chemistry determines the interaction with electrolyte molecules and thus critically regulates the Li+ behaviors at the interfaces. Herein, we probe into the role of electrolyte/filler interfaces (EFI) in CPEs and promote Li+ conduction by introducing an unsaturated coordination Prussian blue analog (UCPBA) filler. Combining scanning transmission X-ray microscope stack imaging studies and first-principle calculations, fast Li+ conduction is revealed only achievable at a chemically stable EFI, which can be established by the unsaturated Co-O coordination in UCPBA to circumvent the side reactions. Moreover, the as-exposed Lewis-acid metal centers in UCPBA efficiently attract the Lewis-base anions of Li salts, which facilitates the Li+ disassociation and enhances its transference number (tLi+). Attributed to these superiorities, the obtained CPEs realize high room-temperature ionic conductivity up to 0.36 mS cm-1 and tLi+ of 0.6, enabling an excellent cyclability of lithium metal electrodes over 4,000 h as well as remarkable capacity retention of 97.6% over 180 cycles at 0.5 C for solid-state lithium-sulfur batteries. This work highlights the crucial role of EFI chemistry in developing highly conductive CPEs and high-performance solid-state batteries.

3.
J Am Chem Soc ; 146(20): 14036-14047, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38725301

RESUMO

The use of nickel-rich layered materials as cathodes can boost the energy density of lithium batteries. However, developing a safe and long-term stable nickel-rich layered cathode is challenging primarily due to the release of lattice oxygen from the cathode during cycling, especially at high voltages, which will cause a series of adverse effects, leading to battery failure and thermal runaway. Surface coating is often considered effective in capturing active oxygen species; however, its process is rather complicated, and it is difficult to maintain intact on the cathode with large volume changes during cycling. Here, we propose an in situ construction of a multifunctional cathode/electrolyte interphase (CEI), which is easy to prepare, repairable, and, most importantly, capable of continuously capturing active oxygen species during the entire life span. This unique protective mechanism notably improves the cycling stability of Li||LiNi0.8Co0.1Mn0.1O2 (NCM811) cells at rigorous working conditions, including ultrahigh voltage (4.8 V), high temperature (60 °C), and fast charging (10 C). An industrial 1 A h graphite||NCM811 pouch cell achieved stable operation of 600 cycles with a capacity retention of 79.6% at 4.4 V, exhibiting great potential for practical use. This work provides insightful guidance for constructing a multifunctional CEI to bypass limitations associated with high-voltage operations of nickel-rich layered cathodes.

4.
J Am Chem Soc ; 2024 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-39031086

RESUMO

The sluggish CO2 reduction and evolution reaction kinetics are thorny problems for developing high-performance Li-CO2 batteries. For the complicated multiphase reactions and multielectron transfer processes in Li-CO2 batteries, exploring efficient cathode catalysts and understanding the interplay between structure and activity are crucial to couple with these pendent challenges. In this work, we applied the CoS as a model catalyst and adjusted its electronic structure by introducing sulfur vacancies to optimize the d-band and p-band centers, which steer the orbital hybridization and boost the redox kinetics between Li and CO2, thus improving the discharge platform of Li-CO2 batteries and altering the deposition behavior of discharge products. As a result, a highly efficient bidirectional catalyst exhibits an ultrasmall overpotential of 0.62 V and a high energy efficiency of 82.8% and circulates stably for nearly 600 h. Meanwhile, density functional theory calculations and multiphysics simulations further elucidate the mechanism of bidirectional activity. This work not only provides a proof of concept to design a remarkably efficient catalyst but also sheds light on promoting the reversible Li-CO2 reaction by tailoring the electronic structure.

5.
J Am Chem Soc ; 146(5): 3553-3563, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38285529

RESUMO

Flexible membranes with ultrathin thickness and excellent mechanical properties have shown great potential for broad uses in solid polymer electrolytes (SPEs), on-skin electronics, etc. However, an ultrathin membrane (<5 µm) is rarely reported in the above applications due to the inherent trade-off between thickness and antifailure ability. We discover a protic solvent penetration strategy to prepare ultrathin, ultrastrong layered films through a continuous interweaving of aramid nanofibers (ANFs) with the assistance of simultaneous protonation and penetration of a protic solvent. The thickness of a pure ANF film can be controlled below 5 µm, with a tensile strength of 556.6 MPa, allowing us to produce the thinnest SPE (3.4 µm). The resultant SPEs enable Li-S batteries to cycle over a thousand times at a high rate of 1C due to the small ionic impedance conferred by the ultrathin characteristic and regulated ionic transportation. Besides, a high loading of the sulfur cathode (4 mg cm-2) with good sulfur utilization was achieved at a mild temperature (35 °C), which is difficult to realize in previously reported solid-state Li-S batteries. Through a simple laminating process at the wet state, the thicker film (tens of micrometers) obtained exhibits mechanical properties comparable to those of thin films and possesses the capability to withstand high-velocity projectile impacts, indicating that our technique features a high degree of thickness controllability. We believe that it can serve as a valuable tool to assemble nanomaterials into ultrathin, ultrastrong membranes for various applications.

6.
EMBO Rep ; 23(3): e53602, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34935271

RESUMO

Cortical expansion and folding are key processes in human brain development and evolution and are considered to be principal elements of intellectual ability. How cortical folding has evolved and is induced during embryo development is not well understood. Here, we show that the expression of human FOXM1 promotes basal progenitor cell proliferation and induces cortical thickening and folding in mice. Human-specific protein sequences further promote the generation of basal progenitor cells. Human FOXM1 increases the proliferation of neural progenitors by binding to the Lin28a promoter and increasing Lin28a expression. Furthermore, overexpression of LIN28A rescues the proliferation of human FOXM1 knockout neural progenitor cells. Together, our findings demonstrate that a human gene can increase the number of basal progenitor cells in mice, leading to brain size increase and gyrification, and may thus contribute to evolutionary brain development and cortical expansion.


Assuntos
Encéfalo/citologia , Proliferação de Células , Proteína Forkhead Box M1 , Células-Tronco Neurais , Animais , Proteína Forkhead Box M1/genética , Proteína Forkhead Box M1/metabolismo , Humanos , Camundongos , Células-Tronco Neurais/citologia , Proteínas de Ligação a RNA
7.
J Am Chem Soc ; 145(13): 7288-7300, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36876987

RESUMO

Recycling spent lithium-ion batteries (LIBs) has become an urgent task to address the issues of resource shortage and potential environmental pollution. However, direct recycling of the spent LiNi0.5Co0.2Mn0.3O2 (NCM523) cathode is challenging because the strong electrostatic repulsion from a transition metal octahedron in the lithium layer provided by the rock salt/spinel phase that is formed on the surface of the cycled cathode severely disrupts Li+ transport, which restrains lithium replenishment during regeneration, resulting in the regenerated cathode with inferior capacity and cycling performance. Here, we propose the topotactic transformation of the stable rock salt/spinel phase into Ni0.5Co0.2Mn0.3(OH)2 and then back to the NCM523 cathode. As a result, a topotactic relithiation reaction with low migration barriers occurs with facile Li+ transport in a channel (from one octahedral site to another, passing through a tetrahedral intermediate) with weakened electrostatic repulsion, which greatly improves lithium replenishment during regeneration. In addition, the proposed method can be extended to repair spent NCM523 black mass, spent LiNi0.6Co0.2Mn0.2O2, and spent LiCoO2 cathodes, whose electrochemical performance after regeneration is comparable to that of the commercial pristine cathodes. This work demonstrates a fast topotactic relithiation process during regeneration by modifying Li+ transport channels, providing a unique perspective on the regeneration of spent LIB cathodes.

8.
J Am Chem Soc ; 145(41): 22516-22526, 2023 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-37788438

RESUMO

Lithium-sulfur (Li-S) batteries suffer from sluggish kinetics due to the poor conductivity of sulfur cathodes and polysulfide shutting. Current studies on sulfur redox catalysis mainly focus on the adsorption and catalytic conversion of lithium polysulfides but ignore the modulation of the electronic structure of the catalysts which involves spin-related charge transfer and orbital interactions. In this work, bimetallic phosphorus trisulfides embedded in Prussian blue analogue-derived nitrogen-doped hollow carbon nanocubes (FeCoPS3/NCs) were elaborately synthesized as a host to reveal the relationship between the catalytic activity and the spin state configuration for Li-S batteries. Orbital spin splitting in FeCoPS3 drives the electronic structure transition from low-spin to high-spin states, generating more unpaired electrons on the 3d orbit. Specifically, the nondegenerate orbitals involved in the high-spin configuration of FeCoPS3 result in the upshift of energy levels, generating more active electronic states. Such tailored electronic structure increases the charge transfer, influences the d-band center, and further modifies the adsorption energy with lithium polysulfides and the potential reaction pathways. Consequently, the cell with FeCoPS3/NC host exhibits an ultralow capacity decay of 0.037% per cycle over 1000 cycles. This study proposed a general strategy for sculpting geometric configurations to enable spin and orbital topology regulation in Li-S battery catalysts.

9.
Mol Psychiatry ; 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858990

RESUMO

Microglia are resident macrophages of the central nervous system that selectively emerge in embryonic cortical proliferative zones and regulate neurogenesis by altering molecular and phenotypic states. Despite their important roles in inflammatory phagocytosis and neurodegenerative diseases, microglial homeostasis during early brain development has not been fully elucidated. Here, we demonstrate a notable interplay between microglial homeostasis and neural progenitor cell signal transduction during embryonic neurogenesis. ARID1A, an epigenetic subunit of the SWI/SNF chromatin-remodeling complex, disrupts genome-wide H3K9me3 occupancy in microglia and changes the epigenetic chromatin landscape of regulatory elements that influence the switching of microglial states. Perturbation of microglial homeostasis impairs the release of PRG3, which regulates neural progenitor cell self-renewal and differentiation during embryonic development. Furthermore, the loss of microglia-driven PRG3 alters the downstream cascade of the Wnt/ß-catenin signaling pathway through its interaction with the neural progenitor receptor LRP6, which leads to misplaced regulation in neuronal development and causes autism-like behaviors at later stages. Thus, during early fetal brain development, microglia progress toward a more homeostatic competent phenotype, which might render neural progenitor cells respond to environmental cross-talk perturbations.

10.
Angew Chem Int Ed Engl ; 62(20): e202301114, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-36869006

RESUMO

The development of flexible zinc-air batteries (FZABs) has attracted broad attention in the field of wearable electronic devices. Gel electrolyte is one of the most important components in FZABs, which is urgent to be optimized to match with Zn anode and adapt to severe climates. In this work, a polarized gel electrolyte of polyacrylamide-sodium citric (PAM-SC) is designed for FZABs, in which the SC molecules contain large amount of polarized -COO- functional groups. The polarized -COO- groups can form an electrical field between gel electrolyte and Zn anode to suppress Zn dendrite growth. Besides, the -COO- groups in PAM-SC can fix H2 O molecules, which prevents water from freezing and evaporating. The polarized PAM-SC hydrogel delivers a high ionic conductivity of 324.68 mS cm-1 and water retention of 96.85 % after being exposed for 96 h. FZABs with the PAM-SC gel electrolyte exhibit long cycling life of 700 cycles at -40 °C, showing the application prospect under extreme conditions.

11.
Small ; 18(34): e2202476, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35905493

RESUMO

Exploring highly active and cost-efficient single-atom catalysts (SACs) for oxygen reduction reaction (ORR) is critical for the large-scale application of Zn-air battery. Herein, density functional theory (DFT) calculations predict that the intrinsic ORR activity of the active metal of SACs follows the trend of Co > Fe > Ni ≈ Cu, in which Co SACs possess the best ORR activity due to its optimized spin density. Guided by DFT calculations, four kinds of transition metal single atoms embedded in 3D porous nitrogen-doped carbon nanosheets (MSAs@PNCN, M = Co, Ni, Fe, Cu) are synthesized via a facile NaCl-template assisted strategy. The resulting MSAs@PNCN displays ORR activity trend in lines with the theoretical predictions, and the Co SAs@PNCN exhibits the best ORR activity (E1/2  = 0.851 V), being comparable to that of Pt/C under alkaline conditions. X-ray absorption fine structure (XAFS) spectra verify the atomically dispersed Co-N4 sites are the catalytically active sites. The highly active CoN4 sites and the unique 3D porous structure contribute to the outstanding ORR performance of Co SAs@PNCN. Furthermore, the Co SAs@PNCN catalyst is employed as cathode in Zn-air battery, which can deliver a large power density of 220 mW cm-2 and maintain robust cycling stability over 530 cycles.

12.
Small ; 18(49): e2205033, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36285776

RESUMO

Transition metal-nitrogen-carbon (TM-N-C) catalysts have been intensely investigated to tackle the sluggish oxygen reduction reactions (ORRs), but insufficient accessibility of the active sites limits their performance. Here, by using solid ZIF-L nanorods as self-sacrifice templates, a ZIF-phase-transition strategy is developed to fabricate ZIF-8 hollow nanorods with open cavities, which can be subsequently converted to atomically dispersed Fe-N-C hollow nanorods (denoted as Fe1 -N-C HNRs) through rational carbonization and following fixation of iron atoms. The microstructure observation and X-ray absorption fine structure analysis confirm abundant Fe-N4 active sites are evenly distributed in the carbon skeleton. Thanks to the highly accessible Fe-N4 active sites provided by the highly porous and open carbon hollow architecture, the Fe1 -N-C HNRs exhibit superior ORR activity and stability in alkaline and acidic electrolytes with very positive half-wave potentials of 0.91 and 0.8 V versus RHE, respectively, both of which surpass those of commercial Pt/C. Remarkably, the dynamic current density (JK ) of Fe1 -N-C HNRs at 0.85 V versus RHE in alkaline media delivers a record value of 148 mA cm-2 , 21 times higher than that of Pt/C. The assembled Zn-air battery using Fe1 -N-C HNRs as cathode catalyst exhibits a high peak power density of 208 mW cm-2 .

13.
Mikrochim Acta ; 188(5): 169, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33891176

RESUMO

Sensitive and accurate detection of DNA methyltransferase (MTase) is conducive to the understanding of the fundamental biological processes related to DNA methylation, clinical disease diagnosis, and drug discovery. Herein, a new fluorescence transducer based on Förster resonance energy transfer (FRET) between the donor upconversion nanoparticles (UCNPs) and the efficient acceptor gold nanorods (AuNRs) for MTase activity analysis and its inhibitor screening is presented. A double-strand DNA linker between UCNPs and AuNRs could be digested by restriction endonuclease HhaI, preventing the FRET process and recovering the upconversion luminescence (UCL) intensity. With the treatment of MTase, the cutting site was disturbed by the methylation of cytosine, blocking the enzyme digestion. The transducer presented here showed an excellent analytical performance toward MTase M.HhaI in the concentration range 0.08~24 U mL-1 with a detection limit of 0.057 U mL-1 calculated according to the UCL intensity changes at 656 nm excited by 980 nm CW laser, which is superior to most of the reported methods. Furthermore, the as-fabricated transducer also demonstrated high testing and screening capability toward enzyme inhibitors' evaluation. The method takes the advantage of low background fluorescence of UCNPs to improve the accuracy of the measurement, which can be developed as a general strategy for the analysis of various disease-related methyltransferase activity and their corresponding inhibitors, offering a promising strategy for high-performance diagnosis, high-efficient drug exploitation, and treatment effectiveness evaluation.


Assuntos
Metilação de DNA , Limite de Detecção
14.
J Adv Nurs ; 76(7): 1647-1657, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32153052

RESUMO

AIM: To identify the intention of Chinese pregnant women to undertake physical activity (PA) using the theory of planned behaviour. DESIGN: A cross-sectional survey. METHODS: From April - October 2017, a cross-sectional questionnaire was completed by 746 pregnant women from the Health Birth Cohort in Wuhan, China. The theory of planned behaviour variables as well as sociodemographic characteristics was recorded, and the Pregnancy PA Questionnaire was together used to assess their PA during pregnancy. RESULTS: Only 11.3% of the women met the international guideline. The intention to undertake PA was found it to be positive in 63.9% of pregnant women. Structural equation modelling analysis revealed that behavioural attitudes, subjective norms, and perceived behavioural control (PBC) influenced PA by directly influencing the behaviour intention. Both behavioural attitude and subjective norms influenced PA by indirectly affecting the behaviour. Overall, the model described 60% variance of the behavioural intention to undertake PA during pregnancy. CONCLUSION: PBC was confirmed to be a prominent factor in determining behavioural intention to undertake PA during pregnancy. Pregnant women should be helped and appropriately guided by health providers to overcome barriers to PA. EFFECT: This study investigates the effect of perceived behavioural control (PBC) on the intention to undertake physical activity (PA). The findings suggest that nurses' and midwives' attention should be focused on how to promote the improvement of perceived behavioural control ability of pregnant women to improve pregnant women's PA intention. The attitude of pregnant women on taking up PA and their ability to control behaviours can be improved with support from family or healthcare providers.


Assuntos
Intenção , Gestantes , China , Estudos Transversais , Exercício Físico , Feminino , Humanos , Gravidez , Teoria Psicológica , Inquéritos e Questionários
15.
Anal Bioanal Chem ; 409(30): 7035-7048, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29116355

RESUMO

A novel anti-tumor candidate drug, 5-chlorogenic acid (5-CQA) injection, was used for the treatment of malignant glioma in clinical trial (phase I) in China. The isolation and identification of the metabolites of 5-CQA injection in humans were investigated in the present study. Urine and feces samples obtained after intramuscular administration of 5-CQA injection to healthy adults have been analyzed by high-performance liquid chromatography coupled with high-resolution mass and multiple-stage mass spectrometry (HPLC-HRMS/MSn). No metabolite was detected in human feces; however, in human urine, a total of six metabolites were identified including isomerized 5-CQA (P1 and P2), hydrolyzed 5-CQA (M1and M2), and methylated 5-CQA (M3 and M4). Among them, M3 and M4 were the main metabolites and target analytes for human mass balance study. Additionally, the structure of M3 and M4 was characterized by high-performance liquid chromatography-solid phase extraction-nuclear magnetic resonance (HPLC-SPE-NMR), and the results demonstrated that the methoxy group of M3 and M4 was exclusively attributed to C-3' and C-4', respectively. Due to the unavailability of commercial reference, the pure products of M3 and M4 were synthesized by 5-CQA methylation and followed by isolation and purification. Moreover, the potential activity of M3 and M4 on malignant glioma was predicted using a reverse molecular docking analysis on eight malignant glioma-related pathways. The results showed that M3 and M4 had various interactions against malignant glioma-related targets. Our study provides an insight into the metabolism of 5-CQA injection in humans and supports the clinical human mass balance study. Graphical abstract ᅟ.


Assuntos
Antineoplásicos/metabolismo , Ácido Clorogênico/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Espectroscopia de Ressonância Magnética/métodos , Espectrometria de Massas/métodos , Adulto , Antineoplásicos/química , Antineoplásicos/urina , Ácido Clorogênico/química , Ácido Clorogênico/urina , Fezes/química , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estrutura Molecular
16.
Mol Pharm ; 11(10): 3371-7, 2014 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-24641274

RESUMO

Formulation of protein and peptide drugs with sustained release properties is crucial to enhance their therapeutic effect and minimize administration frequency. In this study, immunomodulating polymeric systems were designed by manufacturing PHBHHx nanoparticles (NPs) containing thymopentin (TP5). The release profile of the drug was studied over a period of 7 days. The PHBHHx NPs containing TP5-phospholipid (PLC) complex (TP5-PLC) displayed a spherical shape with a mean size, zeta potential, and encapsulation efficiency of 238.9 nm, -32.0 mV, and 72.81%, respectively. The cytotoxicity results showed the PHBHHx NPs had a relatively low toxicity in vitro. TP5 entrapped in the NPs could hardly release in vitro, while the NPs had longer than 7 days release duration after a single subcutaneous injection in Wistar rats. The immunodepression rat model was built to evaluate the immunomodulating effects of TP5-PLC-NPs in vivo. The results of T-lymphocyte subsets (CD3(+), CD4(+), CD8(+), and CD4(+)/CD8(+) ratio) analysis and superoxide dismutase (SOD) values suggested that TP5-PLC-NPs had stronger immunoregulation effects than TP5 solution. In conclusion, an applicable approach to markedly enhancing the loading of a water-soluble peptide into a hydrophobic polymer matrix has been introduced. Thus, TP5-PLC-NPs are promising nanomedicine systems for sustained release effects of TP5.


Assuntos
Glycine max/química , Nanopartículas/química , Fosfolipídeos/química , Polímeros/química , Timopentina/química , Timopentina/imunologia , Adjuvantes Imunológicos/química , Animais , Masculino , Ratos , Ratos Wistar
17.
Nanotechnology ; 25(24): 245705, 2014 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-24869981

RESUMO

Although monomethoxy(polyethyleneglycol)-poly (D,L-lactic-co-glycolic acid)-monomethoxy (PELGE) nanoparticles have been widely studied as a drug delivery system, little is known about their toxicity in vivo. Here we examined the subchronic toxicity and immunotoxicity of different doses of PELGE nanoparticles with diameters of 50 and 200 nm (PELGE50 and PELGE200) in rats. Neither size of PELGE nanoparticles showed obvious subchronic toxic effects during 28 d of continuous intravenous administration based on clinical observation, body weight, hematology parameters and histopathology analysis. PELGE200 nanoparticles showed no overt signs of immunotoxicity based on organ coefficients, histopathology analysis, immunoglobulin levels, blood lymphocyte subpopulations and splenocyte cytokines. Conversely, PELGE50 nanoparticles were associated with an increased organ coefficient and histopathological changes in the spleen, increased serum IgM and IgG levels, alterations in blood lymphocyte subpopulations and enhanced expression of spleen interferon-γ. Taken together, these results suggest that PELGE nanoparticles show low subchronic toxicity but substantial immunotoxicity, which depends strongly on particle size. These findings will be useful for safe application of PELGE nanoparticles in drug delivery systems.


Assuntos
Portadores de Fármacos/toxicidade , Nanopartículas/toxicidade , Poliésteres/toxicidade , Polietilenoglicóis/toxicidade , Administração Intravenosa , Animais , Peso Corporal/efeitos dos fármacos , Testes Imunológicos de Citotoxicidade , Relação Dose-Resposta a Droga , Portadores de Fármacos/síntese química , Ingestão de Alimentos/efeitos dos fármacos , Masculino , Nanopartículas/administração & dosagem , Nanopartículas/química , Tamanho da Partícula , Poliésteres/administração & dosagem , Poliésteres/síntese química , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/síntese química , Ratos , Ratos Wistar , Baço/citologia , Baço/efeitos dos fármacos , Sobrevivência de Tecidos/efeitos dos fármacos
18.
J Ethnopharmacol ; 334: 118559, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39002825

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Angelica sinensis (AS) and Chuanxiong rhizoma (CR) are frequently prescribed in clinical settings for their ability to enrich blood, regulate menstrual cycles, and alleviate pain. Despite their widespread use, there is a relative dearth of studies exploring their anti-inflammatory properties. AIM OF THE STUDY: To evaluate the antioxidant and anti-inflammatory effects of Angelica sinensis-Chuanxiong rhizoma (ASCR) extracts and investigate its anti-inflammatory mechanisms. MATERIALS AND METHODS: AS and CR were combined in six ratios and extracted using five solvents. The quality of the resulting ASCR extracts was assessed by determining the content of ferulic acid (FA) using HPLC. The antioxidant effects of the ASCR extracts were evaluated in vitro using the DPPH and ABTS assays, as well as in HUVECs exposed to H2O2-induced oxidative damage. Additionally, the anti-inflammatory effects of the extracts were investigated in vivo through the assays of ear edema in mice and paw edema in rats. Biochemical markers including NO, MDA, and SOD in paw tissues, as well as PGE2, TNF-α, and COX-2 in rat serum, were measured to further elucidate the anti-inflammatory mechanisms of ASCR extracts. RESULTS: The WA-2-1 was obtained by combining AS and CR in a 2:1 ratio through first water then ethanol extraction, and showed favorable antioxidant and anti-inflammatory activities. The extract demonstrated effective scavenging abilities against DPPH• and ABTS+• radicals while also protecting against H2O2-induced oxidative damage. Furthermore, in vivo studies revealed that WA-2-1 had significant inhibitory effects on ear and paw edema as well as the ability to decrease NO and MDA levels, enhance SOD activity, and downregulate the expression of COX-2, PGE2, and TNF-α. CONCLUSIONS: The combination of AS and CR exhibits favorable anti-inflammatory effects, attributed to its dual actions of mitigating oxidative stress and suppressing the production of inflammatory mediators in serum or tissues during the inflammatory process.

19.
Dev Cell ; 59(1): 108-124.e7, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38101413

RESUMO

Microglia are highly heterogeneous as resident immune cells in the central nervous system. Although the proinflammatory phenotype of microglia is driven by the metabolic transformation in the disease state, the mechanism of metabolic reprogramming in microglia and whether it affects surrounding astrocyte progenitors have not been well elucidated. Here, we illustrate the communication between microglial metabolism and astrogenesis during embryonic development. The transcription factor BTB and CNC homology 1 (Bach1) reduces lactate production by inhibiting two key enzymes, HK2 and GAPDH, during glycolysis. Metabolic perturbation of microglia reduces lactate-dependent histone modification enrichment at the Lrrc15 promoter. The microglia-derived LRRC15 interacts with CD248 to participate in the JAK/STAT pathway and influence astrogenesis. In addition, Bach1cKO-Cx3 mice exhibit abnormal neuronal differentiation and anxiety-like behaviors. Altogether, this work suggests that the maintenance of microglia metabolic homeostasis during early brain development is closely related to astrogenesis, providing insights into astrogenesis and related diseases.


Assuntos
Janus Quinases , Microglia , Animais , Feminino , Camundongos , Gravidez , Encéfalo/metabolismo , Janus Quinases/metabolismo , Lactatos/metabolismo , Microglia/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo
20.
Adv Mater ; 36(1): e2303610, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37500064

RESUMO

The localized reaction heterogeneity of the sulfur cathode and the uneven Li deposition on the Li anode are intractable issues for lithium-sulfur (Li-S) batteries under practical operation. Despite impressive progress in separately optimizing the sulfur cathode or Li anode, a comprehensive understanding of the highly coupled relationship between the cathode and anode is still lacking. In this work, inspired by the Butler-Volmer equation, a binary descriptor (IBD ) assisting the rational structural design of sulfur cathode by simultaneously considering the mass-transport index (Imass ) and the charge-transfer index (Icharge ) is identified, and subsequently the relationship between IBD and the morphological evolution of Li anode is established. Guided by the IBD , a scalable electrode providing interpenetrated flow channels for efficient mass/charge transfer, full utilization of active sulfur, and mechanically elastic support for aggressive electrochemical reactions under practical conditions is reported. These characteristics induce a homogenous distribution of local current densities and reduced reaction heterogeneity on both sides of the cathode and anode. Impressive energy density of 318 Wh kg-1 and 473 Wh L-1 in an Ah-level pouch cell can be achieved by the design concept. This work offers a promising paradigm for unlocking the interaction between cathode and anode and designing high-energy practical Li-S batteries.

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