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1.
J Chem Phys ; 161(5)2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39092945

RESUMO

The chemiresistive effect of an oxide significantly influences its electrical properties, which depend greatly on the interactions between the ambient gas molecules and the solid surface, including the gas adsorption and charge transfer still challenging to be clarified. In this work, we investigate the chemiresistive effect of the p-type delafossite CuScO2 microsheets by comparing their responses to various gaseous alcohols, which increase with an approximately linear relationship with the length of straight carbon chains from methanol to n-hexanol. A new mechanism is proposed to elucidate such a dramatic trend of observed chemiresistive change based on the first-principles calculations and test results. The increasing carbon chain length modulates the adsorption configuration and provides supplementary routes for electron transfer, which is assumed to account for the observed chemiresistive effect. This work may provide a novel perspective for the investigation and development of more advanced functional oxides for electrical applications.

3.
Sci Total Environ ; : 175450, 2024 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-39134270

RESUMO

Reservoir nearshore areas are influenced by both terrestrial and aquatic ecosystems, making them sensitive regions to water quality changes. The analysis of basin landscape hydrological features provides limited insight into the spatial heterogeneity of eutrophication in these areas. The complex characteristics of shoreline morphology and their impact on eutrophication are often overlooked. To comprehensively analyze the complex relationships between shoreline morphology and landscape hydrological features, with eutrophication, this study uses Danjiangkou Reservoir as a case study. Utilizing Landsat 8 OLI remote sensing data from 2013 to 2022, combined with a semi-analytical approach, the spatial distribution of the Trophic State Index (TSI) during flood discharge periods (FDPs) and water storage periods (WSPs) was obtained. Using Extreme Gradient Boosting (XGBoost) and SHapley Additive exPlanations (SHAP), explained the relationships between landscape composition, landscape configuration, hydrological topography, shoreline morphology, and TSI, identified key factors at different spatial scales and validated their reliability. The results showed that: (1) There is significant spatial heterogeneity in the TSI distribution of Danjiangkou Reservoir. The eutrophication levels are significant in the shoreline and bay areas, with a tendency to extend inward only during the WSPs. (2) The importance of landscape composition, landscape configuration, hydrological topography, and shoreline morphology to TSI variations during the FDPs are 25.12 %, 29.6 %, 23.09 %, and 22.19 % respectively. Besides shoreline distance, the Landscape Shape Index (LSI) and Hypsometric Integral (HI) are the two most significant environmental variables overall during the FDPs. Forest and grassland areas become the most influential factors during the WSPs. The influence of landscape patterns and hydrological topography on TSI varies at different spatial scales. At the 200 m riparian buffer zone, the increase in cropland and impervious areas significantly elevates eutrophication levels. (3) Morphology complexity, shows a noticeable threshold effect on TSI, with complex shoreline morphology increasing the risk of eutrophication.

4.
Ecotoxicol Environ Saf ; 283: 116858, 2024 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-39137464

RESUMO

Organophosphate flame retardants 2-ethylhexyldiphenyl phosphate (EHDPP) and cadmium (Cd) are ubiquitous in environmental matrices, and dermal absorption is a major human exposure pathway. However, their detrimental effects on the human epidermis remain largely unknown. In this study, human keratinocytes (HaCaT cells) were employed to examine the toxicity and underlying mechanisms of co-exposure to EHDPP and Cd. Their influence on cell morphology and viability, oxidative damage, apoptosis, and tight junction were determined. The results showed that co-exposure decreased cell viability by >40 %, induced a higher level of oxidative damage by increasing the generation of reactive oxygen species (1.3 folds) and inhibited CAT (79 %) and GPX (90 %) activities. Moreover, Cd exacerbated EHDPP-induced mitochondrial disorder and cellular apoptosis, which was evidenced by a reduction in mitochondrial membrane potential and an elevation of cyt-c and Caspase-3 mRNA expression. In addition, greater loss of ZO-1 immunoreactivity at cellular boundaries was observed after co-exposure, indicating skin epithelial barrier function disruption, which may increase the human bioavailability of contaminants via the dermal absorption pathway. Taken together, oxidative damage, cell apoptosis, and tight junction disruption played a crucial role in EHDPP + Cd triggered cytotoxicity in HaCaT cells. The detrimental effects of EHDPP + Cd co-exposure were greater than individual exposure, suggesting the current health risk assessment or adverse effects evaluation of individual exposure may underestimate their perniciousness. Our data imply the importance of considering the combined exposure to accurately assess their health implication.

5.
Plant Physiol Biochem ; 215: 109017, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39121518

RESUMO

Cadmium (Cd) contamination of soil may lead to Cd stress for plants, which significantly hinders plant growth and development, posing a risk to human health through the consumption of Cd-contaminated foods. Watermelon (Citrullus lanatus), a widely consumed fruit, is particularly affected by Cd stress globally, yet the mechanisms underlying its response are not well understood. Here, we subjected watermelon seedlings to simulated Cd stress treatment and explored the physiological, transcriptomic, and metabolic response. Our findings revealed that Cd stress treatment led to increased accumulation of reactive oxygen species (ROS) in watermelon leaves. Transcriptome sequencing unveiled a multitude of osmotic and oxidative stress-responsive genes, including peroxidase (POD), MYB, voltage-dependent anion channel (SLAC1), and ABC transporter. KEGG enrichment analysis highlighted the predominant enrichment of Cd stress-responsive genes in pathways such as glutathione (GSH) metabolism, MAPK signaling, and biosynthesis of secondary metabolites. Within the GSH metabolism pathway, several glutathione S-transferase (GST) genes were up-regulated, alongside phytochelatin synthetase (PCS) genes involved in phytochelatin synthesis. In the MAPK signaling pathway, genes associated with ABA and ethylene signal transduction showed up-regulation following Cd stress. Metabolomic analysis demonstrated that Cd stress enhanced the production of amino acids, phenolamines, and esters. Overall, our study elucidates that watermelon responds to Cd stress by activating its antioxidant system, GSH metabolism pathway, MAPK signal pathway, and biosynthesis of key metabolites. These findings offer valuable insights for the remediation of heavy metal pollution in soil affecting plant life.

6.
Molecules ; 29(15)2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39125009

RESUMO

Human pharyngeal squamous cell carcinoma (HPSCC) is the most common malignancy in the head and neck region, characterized by high mortality and a propensity for metastasis. Fucoxanthin, a carotenoid isolated from brown algae, exhibits pharmacological properties associated with the suppression of tumor proliferation and metastasis. Nevertheless, its potential to inhibit HPSCC proliferation and metastasis has not been fully elucidated. This study represents the first exploration of the inhibitory effects of fucoxanthin on two human pharyngeal squamous carcinoma cell lines (FaDu and Detroit 562), as well as the mechanisms underlying those effects. The results showed dose-dependent decreases in the proliferation, migration, and invasion of HPSCC cells after fucoxanthin treatment. Further studies indicated that fucoxanthin caused a significant reduction in the expression levels of proteins in the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) pathway, as well as the downstream proteins matrix metalloproteinase (MMP)-2 and MMP-9. Specific activators of PI3K/AKT reversed the effects of fucoxanthin on these proteins, as well as on cell proliferation and metastasis, in FaDu and Detroit 562 cells. Molecular docking assays confirmed that fucoxanthin strongly interacted with PI3K, AKT, mTOR, MMP-2, and MMP-9. Overall, fucoxanthin, a functional food component, is a potential therapeutic agent for HPSCC.


Assuntos
Movimento Celular , Proliferação de Células , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Xantofilas , Humanos , Serina-Treonina Quinases TOR/metabolismo , Xantofilas/farmacologia , Xantofilas/química , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proliferação de Células/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias Faríngeas/tratamento farmacológico , Neoplasias Faríngeas/patologia , Neoplasias Faríngeas/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Metástase Neoplásica , Simulação de Acoplamento Molecular
7.
Heliyon ; 10(14): e33781, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39113995

RESUMO

This research examines the unique Chinese approaches to implementing the Early Childhood Curriculum (ECC) in Shenzhen and Hong Kong, drawing on School-based Curriculum Development (SBCD) studies. A total of 200 administrators and teachers were interviewed in total, and transcripts from those interviews were examined, cross-checked, and assessed using document analysis and classroom observation. Through interviews that have been conducted by administrators and teachers analyzed by document analysis and classroom observation, the influence of Chinese culture on ECC implementation is explored using the Cultural-Historical Activity Theory (CHAT). An exploratory, inferential, and descriptive statistical approach evaluates the sociocultural mechanism of ECC in Chinese society. The proposed framework utilizes K-Nearest Neighbor (KNN) regression analysis to illustrate how social development leads to cultural fusion and conflicts. The overall sociocultural framework promotes cultural growth and inheritance in China's early childhood education settings.

8.
Front Immunol ; 15: 1437834, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39114651

RESUMO

Introduction: Off-season upsurge of respiratory syncytial virus (RSV) infection with changed characteristics and heightened clinical severity during the post-COVID-19 era are raising serious concerns. This study aimed to develop and validate a nomogram for predicting the risk of severe acute lower respiratory tract infection (SALRTI) in children hospitalized for RSV infection during the post-COVID-19 era using machine learning techniques. Methods: A multicenter retrospective study was performed in nine tertiary hospitals in Yunnan, China, enrolling children hospitalized for RSV infection at seven of the nine participating hospitals during January-December 2023 into the development dataset. Thirty-nine variables covering demographic, clinical, and laboratory characteristics were collected. Primary screening and dimension reduction of data were performed using Least Absolute Shrinkage and Selection Operator (LASSO) regression, followed by identification of independent risk factors for RSV-associated SALRTI using Logistic regression, thus finally establishing a predictive nomogram model. Performance of the nomogram was internally evaluated by receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) based on the development dataset. External validation of our model was conducted using same methods based on two independent RSV cohorts comprising pediatric RSV inpatients from another two participating hospitals between January-March 2024. Results: The development dataset included 1102 patients, 239 (21.7%) of whom developed SALRTI; while the external validation dataset included 249 patients (142 in Lincang subset and 107 in Dali subset), 58 (23.3%) of whom were diagnosed as SALRTI. Nine variables, including age, preterm birth, underlying condition, seizures, neutrophil-lymphocyte ratio (NLR), interleukin-6 (IL-6), lactate dehydrogenase (LDH), D-dimer, and co-infection, were eventually confirmed as the independent risk factors of RSV-associated SALRTI. A predictive nomogram was established via integrating these nine predictors. In both internal and external validations, ROC curves indicated that the nomogram had satisfactory discrimination ability, calibration curves demonstrated good agreement between the nomogram-predicted and observed probabilities of outcome, and DCA showed that the nomogram possessed favorable clinical application potential. Conclusion: A novel nomogram combining several common clinical and inflammatory indicators was successfully developed to predict RSV-associated SALRTI. Good performance and clinical effectiveness of this model were confirmed by internal and external validations.


Assuntos
COVID-19 , Hospitalização , Nomogramas , Infecções por Vírus Respiratório Sincicial , SARS-CoV-2 , Humanos , Infecções por Vírus Respiratório Sincicial/diagnóstico , Infecções por Vírus Respiratório Sincicial/epidemiologia , COVID-19/diagnóstico , COVID-19/epidemiologia , Masculino , Feminino , Lactente , Estudos Retrospectivos , Pré-Escolar , China/epidemiologia , Criança , Índice de Gravidade de Doença , Fatores de Risco , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/virologia , Aprendizado de Máquina , Recém-Nascido , Curva ROC
9.
Nano Lett ; 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39145617

RESUMO

Low-dimensional semiconductor-based field-effect transistor (FET) biosensors are promising for label-free detection of biotargets while facing challenges in mass fabrication of devices and reliable reading of small signals. Here, we construct a reliable technology for mass production of semiconducting carbon nanotube (CNT) film and FET biosensors. High-uniformity randomly oriented CNT films were prepared through an improved immersion coating technique, and then, CNT FETs were fabricated with coefficient of performance variations within 6% on 4-in. wafers (within 9% interwafer) based on an industrial standard-level process. The CNT FET-based ion sensors demonstrated threshold voltage standard deviations within 5.1 mV at each ion concentration, enabling direct reading of the concentration information based on the drain current. By integrating bioprobes, we achieved detection of biosignals as low as 100 aM through a plug-and-play portable detection system. The reliable technology will contribute to commercial applications of CNT FET biosensors, especially in point-of-care tests.

10.
Infect Drug Resist ; 17: 3125-3132, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39050826

RESUMO

Objective: To explore the association between the variant mutations within embB and ubiA, and the degree of ethambutol (EMB) resistance of Mycobacterium tuberculosis (M. tuberculosis) isolates. Methods: A total of 146 M. tuberculosis isolates were used to determine the minimum inhibitory concentrations (MICs) of EMB with a 96-well microplate-based assay. The mutations within embB and ubiA among these isolates were identified with DNA sequencing. Moreover, a multivariate regression model and a computer model were established to assess the effects of mutations on EMB resistance. Results: Our data showed that overall 100 isolates exhibited 28 mutated patterns within the sequenced embB and ubiA. Statistical analysis indicated that embB mutations Met306Val, Met306Ile, Gly406Ala, and Gln497Arg, were strongly associated with EMB resistance. Of these mutations, Met306Val and Gln497Arg were significantly associated with high-level EMB resistance. Almost all multiple mutations occurred in high-level EMB-resistant isolates. Although the mutation within ubiA accompanied with embB mutation presented exclusively in EMB-resistant isolates, four single ubiA mutations (Ala39Glu, Ser173Ala, Trp175Cys, and Val283Leu) leading to protein instability were observed in EMB-susceptible isolates. Conclusion: This study highlighted the complexity of EMB resistance. Some individual mutations and multiple mutations within embB and ubiA contributed to the different levels of EMB resistance.

11.
J Agric Food Chem ; 72(30): 16867-16876, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39021280

RESUMO

Synthetic aromatic esters, widely employed in agriculture, food, and chemical industries, have become emerging environmental pollutants due to their strong hydrophobicity and poor bioavailability. This study attempted to address this issue by extracellularly expressing the promiscuous aminopeptidase (Aps) from Pseudomonas aeruginosa GF31 in B. subtilis, achieving an impressive enzyme activity of 13.7 U/mg. Notably, we have demonstrated, for the first time, the Aps-mediated degradation of diverse aromatic esters, including but not limited to pyrethroids, phthalates, and parabens. A biochemical characterization of Aps reveals its esterase properties and a broader spectrum of substrate profiles. The degradation rates of p-nitrobenzene esters (p-NB) with different side chain structures vary under the action of Aps, showing a preference for substrates with relatively longer alkyl side chains. The structure-dependent degradability aligns well with the binding energies between Aps and p-NB. Molecular docking and enzyme-substrate interaction elucidate that hydrogen bonding, hydrophobic interactions, and π-π stacking collectively stabilize the enzyme-substrate conformation, promoting substrate hydrolysis. These findings provide new insights into the enzymatic degradation of aromatic ester pollutants, laying a foundation for the further development and modification of promiscuous enzymes.


Assuntos
Aminopeptidases , Proteínas de Bactérias , Ésteres , Simulação de Acoplamento Molecular , Pseudomonas aeruginosa , Hidrólise , Ésteres/metabolismo , Ésteres/química , Aminopeptidases/metabolismo , Aminopeptidases/química , Aminopeptidases/genética , Especificidade por Substrato , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Pseudomonas aeruginosa/enzimologia , Biodegradação Ambiental , Cinética , Bacillus subtilis/enzimologia , Ácidos Ftálicos/química , Ácidos Ftálicos/metabolismo
12.
Biomolecules ; 14(7)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39062533

RESUMO

In Asian populations with non-small-cell lung cancer (NSCLC), EGFR mutations are highly prevalent, occurring in roughly half of these patients. Studies have revealed that individuals with EGFR mutation typically fare worse with immunotherapy. In patients who received EGFR tyrosine kinase inhibitor (TKI) treatment followed by anti-PD-1 therapy, poor results were observed. The underlying mechanism remains unclear. We used high-resolution flow cytometry and ELISA to detect the circulating level of small extracellular vesicle (sEV) PD-L1 in NSCLC individuals with EGFR mutations before and after receiving TKIs. The secretion amount of sEV PD-L1 of lung cancer cell lines with EGFR mutations under TKI treatment or not were detected using high-resolution flow cytometry and Western blotting. The results revealed that patients harboring EGFR mutations exhibit increased levels of sEV PD-L1 in circulation, which inversely correlated with the presence of CD8+ T cells in tumor tissues. Furthermore, tumor cells carrying EGFR mutations secrete a higher quantity of PD-L1-positive sEVs. TKI treatment appeared to amplify the levels of PD-L1-positive sEVs in the bloodstream. Mutation-induced and TKI-induced sEVs substantially impaired the functionality of CD8+ T cells. Importantly, our findings indicated that EGFR mutations and TKI therapies promote secretion of PD-L1-positive sEVs via distinct molecular mechanisms, namely the HRS and ALIX pathways, respectively. In conclusion, the increased secretion of PD-L1-positive sEVs, prompted by genetic alterations and TKI administration, may contribute to the limited efficacy of immunotherapy observed in EGFR-mutant patients and patients who have received TKI treatment.


Assuntos
Antígeno B7-H1 , Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Vesículas Extracelulares , Neoplasias Pulmonares , Mutação , Inibidores de Proteínas Quinases , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Receptores ErbB/genética , Receptores ErbB/metabolismo , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Feminino , Linhagem Celular Tumoral , Masculino , Pessoa de Meia-Idade , Idoso , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Terapia de Imunossupressão
13.
Int J Mol Sci ; 25(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39062748

RESUMO

Henosepilachna vigintioctomaculata is distributed in several Asian countries. The larvae and adults often cause substantial economic losses to Solanaceae crops such as potato, tomato, eggplant, and Chinese boxthorn. Even though a chromosome-level genome has been documented, the expression profiles of genes involved in development are not determined. In this study, we constructed embryonic, larval, pupal, and adult transcriptomes, generated a comprehensive RNA-sequencing dataset including ~52 Gb of clean data, and identified 602,773,686 cleaned reads and 33,269 unigenes. A total of 18,192 unigenes were successfully annotated against NCBI nonredundant protein sequences, Swissprot, Eukaryotic Orthologous Groups, Gene Ontology (GO), or Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. There were 3580, 2040, 5160, 2496, 3008, and 3895 differentially expressed genes (DEGs) between adult/egg, egg/larval, larval/pupal, adult/pupal, egg/pupal, and adult/larval samples, respectively. GO and KEGG analyses of the DEGs highlighted several critical pathways associated with specific developing stages. This is the first comprehensive transcriptomic dataset encompassing all developmental stages in H. vigintioctomaculata. Our data may facilitate the exploitation of gene targets for pest control and can serve as a valuable gene resource for future molecular investigations.


Assuntos
Perfilação da Expressão Gênica , Transcriptoma , Animais , Perfilação da Expressão Gênica/métodos , Transcriptoma/genética , Regulação da Expressão Gênica no Desenvolvimento , Anotação de Sequência Molecular , Ontologia Genética , Larva/genética , Larva/crescimento & desenvolvimento
16.
Angew Chem Int Ed Engl ; : e202411508, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014940

RESUMO

The conversion of CO2 to C2 through photocatalysis poses significant challenges, and one of the biggest hurdles stems from the sluggishness of the multi-electron transfer process. Herein, taking metal-organic framework (PFC-98) as a model photocatalyst, we report a new strategy to facilitate charge separation. This strategy involves matching the energy levels of the lowest unoccupied node and linker orbitals of the MOF, thereby creating the lowest unoccupied crystal orbital (LUCO) delocalized over both the node and linker. This feature enables the direct excitation of electrons from photosensitive linker to the catalytic centers, achieving a direct charge transfer (DCT) pathway. For comparison, an isoreticular MOF (PFC-6) based on analogue components but with far apart frontier energy level was synthesized. The delocalized LUCO caused the presence of an internal charge-separated state (ICS), prolonging the excited state lifetime and further inhibiting the electron-hole recombination. The presence of an internal charge-separated state (ICS) prolongs the excited state lifetime and further inhibits the electron-hole recombination. Moreover, it also induced abundant electrons accumulating at the catalytic sites, enabling the multi-electron transfer process. As a result, the material featuring delocalized LUCO exhibits superior overall CO2 photocatalytic performance with high C2 production yield and selectivity.

17.
Phys Chem Chem Phys ; 26(28): 19217-19227, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38957117

RESUMO

An inverse sandwich structure has been computationally predicted for uranium boride and extended to the series of actinide elements (An) from Th to Cm. The electronic structure and chemical bonding of these novel compounds have been analyzed using density functional theory and multireference wave-function based methods. We report the trends in electronic structure and bonding for An2B8, and found that (d-π)π and (d-p)δ are the most important factors in the stability of An2B8. The (f-p)δ bond provides extra stabilization for Pa2B8 and U2B8, owing to the extensive interactions of An-B8-An, resulting in a short distance for the Pa-Pa and U-U bonds.

18.
BMC Cardiovasc Disord ; 24(1): 354, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38992615

RESUMO

BACKGROUND: Hyperlipidemia damages vascular wall and serves as a foundation for diseases such as atherosclerosis, hypertension and stiffness. The NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome is implicated in vascular dysfunction associated with hyperlipidemia-induced vascular injury. Sodium tanshinone IIA sulfonate (STS), a well-established cardiovascular protective drug with recognized anti-inflammatory, antioxidant, and vasodilatory properties, is yet to be thoroughly investigated for its impact on vascular relaxant imbalance induced by hyperlipidemia. METHODS: In this study, we treated ApoE-knockout (ApoE-/-) mouse with STS and assessed the activation of the NLRP3 inflammasome, expression of MMP2/9, integrity of elastic fibers, and vascular constriction and relaxation. RESULTS: Our findings reveal that STS intervention effectively preserves elastic fibers, significantly restores aortic relaxation function in ApoE-/- mice, and reduces their excessive constriction. Furthermore, STS inhibits the phosphorylation of spleen tyrosine kinase (SYK), suppresses NLRP3 inflammasome activation, and reduces MMP2/9 expression. CONCLUSIONS: These results demonstrate that STS protects vascular relaxation against hyperlipidemia-induced damage through modulation of the SYK-NLRP3 inflammasome-MMP2/9 pathway. This research provides novel insights into the mechanisms underlying vascular relaxation impairment in a hyperlipidemic environment and uncovers a unique mechanism by which STS preserves vascular relaxation, offering valuable foundational research evidence for its clinical application in promoting vascular health.


Assuntos
Modelos Animais de Doenças , Inflamassomos , Metaloproteinase 2 da Matriz , Metaloproteinase 9 da Matriz , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Proteína 3 que Contém Domínio de Pirina da Família NLR , Fenantrenos , Transdução de Sinais , Quinase Syk , Vasodilatação , Animais , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Inflamassomos/metabolismo , Quinase Syk/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Fenantrenos/farmacologia , Masculino , Metaloproteinase 9 da Matriz/metabolismo , Vasodilatação/efeitos dos fármacos , Hiperlipidemias/tratamento farmacológico , Hiperlipidemias/fisiopatologia , Vasodilatadores/farmacologia , Fosforilação , Camundongos , Aorta/efeitos dos fármacos , Aorta/fisiopatologia , Aorta/metabolismo , Aorta/enzimologia , Apolipoproteínas E
20.
J Colloid Interface Sci ; 674: 925-937, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-38959738

RESUMO

Proton exchange membranes with high ionic conductivity and good chemical stability are critical for achieving high power density and long lifespan of direct methanol cells (DMFCs). Herein, a zwitterionic molecule was grafted onto the surface of polyvinylidene fluoride (PVDF) nanofibers to obtain functionalized PVDF porous substrate (SBMA-PDA@PVDF). Then, sulfonated poly(ether ether ketone) (SPEEK) was filled into the pores of SBMA-PDA@PVDF, and further ionic cross-linked via H2SO4 to prepare the composite membrane (SBMA-PDA@PVDF/SPEEK). The basic groups on the zwitterionic interface could not only establish ionic cross-linking with SPEEK to increase chemical stability and reduce swelling, but also serve as the adsorption sites for subsequent H2SO4 cross-linking to significantly enhance proton conductivity. Super-high proton conductivity (165.34 mS cm-1, 80 °C) was achieved for the membrane, which was 2.12 times higher than that of the pure SPEEK. Moreover, the SBMA-PDA@PVDF/SPEEK membrane exhibited remarkably improved oxidative stability of 91.6 % mass retention after soaking in Fenton's agent for 12 h, while pure SPEEK completely decomposed. Satisfactorily, the DMFC assembled with SBMA-PDA@PVDF/SPEEK exhibited a peak power density of 99.01 mW cm-2, which was twice as much as that of commercial Nafion 212 (48.88 mW cm-2). After 235 h durability test, only 11 % voltage loss was observed.

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