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1.
JAMA ; 332(13): 1059-1069, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39235816

RESUMO

Importance: Previous randomized clinical trials did not demonstrate the superiority of endovascular stenting over aggressive medical management for patients with symptomatic intracranial atherosclerotic stenosis (sICAS). However, balloon angioplasty has not been investigated in a randomized clinical trial. Objective: To determine whether balloon angioplasty plus aggressive medical management is superior to aggressive medical management alone for patients with sICAS. Design, Setting, and Participants: A randomized, open-label, blinded end point clinical trial at 31 centers across China. Eligible patients aged 35 to 80 years with sICAS defined as recent transient ischemic attack (<90 days) or ischemic stroke (14-90 days) before enrollment attributed to a 70% to 99% atherosclerotic stenosis of a major intracranial artery receiving treatment with at least 1 antithrombotic drug and/or standard risk factor management were recruited between November 8, 2018, and April 2, 2022 (final follow-up: April 3, 2023). Interventions: Submaximal balloon angioplasty plus aggressive medical management (n = 249) or aggressive medical management alone (n = 252). Aggressive medical management included dual antiplatelet therapy for the first 90 days and risk factor control. Main Outcomes and Measures: The primary outcome was a composite of any stroke or death within 30 days after enrollment or after balloon angioplasty of the qualifying lesion or any ischemic stroke in the qualifying artery territory or revascularization of the qualifying artery after 30 days through 12 months after enrollment. Results: Among 512 randomized patients, 501 were confirmed eligible (mean age, 58.0 years; 158 [31.5%] women) and completed the trial. The incidence of the primary outcome was lower in the balloon angioplasty group than the medical management group (4.4% vs 13.5%; hazard ratio, 0.32 [95% CI, 0.16-0.63]; P < .001). The respective rates of any stroke or all-cause death within 30 days were 3.2% and 1.6%. Beyond 30 days through 1 year after enrollment, the rates of any ischemic stroke in the qualifying artery territory were 0.4% and 7.5%, respectively, and revascularization of the qualifying artery occurred in 1.2% and 8.3%, respectively. The rate of symptomatic intracranial hemorrhage in the balloon angioplasty and medical management groups was 1.2% and 0.4%, respectively. In the balloon angioplasty group, procedural complications occurred in 17.4% of patients and arterial dissection occurred in 14.5% of patients. Conclusions and Relevance: In patients with sICAS, balloon angioplasty plus aggressive medical management, compared with aggressive medical management alone, statistically significantly lowered the risk of a composite outcome of any stroke or death within 30 days or an ischemic stroke or revascularization of the qualifying artery after 30 days through 12 months. The findings suggest that balloon angioplasty plus aggressive medical management may be an effective treatment for sICAS, although the risk of stroke or death within 30 days of balloon angioplasty should be considered in clinical practice. Trial Registration: ClinicalTrials.gov Identifier: NCT03703635.


Assuntos
Angioplastia com Balão , Arteriosclerose Intracraniana , Inibidores da Agregação Plaquetária , Humanos , Pessoa de Meia-Idade , Feminino , Masculino , Idoso , Inibidores da Agregação Plaquetária/uso terapêutico , Arteriosclerose Intracraniana/terapia , Adulto , AVC Isquêmico , Terapia Combinada , Fibrinolíticos/uso terapêutico , Ataque Isquêmico Transitório , Idoso de 80 Anos ou mais
2.
J Ethnopharmacol ; 337(Pt 1): 118816, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39270881

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The prevalence of allergic airway inflammation (AAI) worldwide is high. Artemisia annua L. pollen is spread worldwide, and allergic diseases caused by its plant polysaccharides, which are closely related to the intestinal microbiota, have anti-inflammatory effects. Further isolation and purification of Lycium barbarum L. yielded its most effective component Lycium barbarum L. glycopeptide (LbGP), which can inhibit inflammation in animal models. However, its therapeutic effect on AAI and its mechanism of regulating the intestinal flora have not been fully investigated. AIM OF THE STUDY: To explore LbGP in APE-induced immunological mechanisms of AAI and the interaction mechanism of the intestinal flora and metabolites. METHODS: A mouse model of AAI generated from Artemisia annua pollen was constructed, and immunological indices related to the disease were examined. A combination of macrogenomic and metabolomic analyses was used to investigate the effects of LbGP on the gut microbial and metabolite profiles of mice with airway inflammation. RESULTS: LbGP effectively alleviated Artemisia. annua pollen extract (APE)-induced AAI, corrected Th1/Th2 immune dysregulation, decreased Th17 cells, increased Treg cells, and altered the composition and function of the intestinal microbiota. LbGP treatment increased the number of OdoribacterandDuncaniella in the intestines of the mice, but the numble of Alistipes and Ruminococcus decreased. Metabolite pathway enrichment analysis were used to determine the effects of taurine and hypotaurine metabolism, bile acid secretion, and pyrimidine metabolism pathways on disease. CONCLUSION: Our results revealed significant changes in the macrogenome and metabolome following APE and LbGP intervention, revealed potential correlations between gut microbial species and metabolites, and highlighted the beneficial effects of LbGP on AAI through the modulation of the gut microbiome and host metabolism.

3.
Parasitol Res ; 123(10): 336, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39347812

RESUMO

Echinococcosis is a zoonotic disease, which seriously endangers human health. The immune game between parasite and host is not fully understood. Exosomes are thought to be one of the ways of information communication between parasite and host. In this study, we attempted to explore the communication between Echinococcus granulosus and its host through the medium of exosomes. We collected plasma from E. granulosus patients (CE-EXO) and healthy donors (HD-EXO) and extracted exosomes from the plasma. The expression profile of miRNA in plasma was determined by second generation sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were used to annotate the function of target genes of differential miRNAs. Meanwhile, we co-cultured plasma exosomes from healthy donors and plasma exosomes from E. granulosus patients with Jurkat T cells with or without phytohaemagglutinin (PHA) stimulation. The expression of CD69 on Jurkat T cells was detected by flow cytometry. The results showed that the miRNA of exosomes between healthy donors and E. granulosus patients was significantly different. GO and KEGG were used to annotate the function of target genes of differential miRNAs. The results indicate that many important pathways are involved in inflammation, metabolism, and immune response after parasite infection, such as p53 signaling pathway, PI3K-Akt signaling pathway, and glycolysis/gluconeogenesis. Flow cytometry showed that CE-EXO reduced the expression of CD69 + on Jurkat T cells. Our present results suggest that these differentially expressed miRNAs may be important regulators of parasite-host interactions. Meanwhile, functional prediction of its target genes provides valuable information for understanding the mechanism of host-parasite interactions. These results provide clues for future studies on E. granulosus escape from host immune attack, which could help control E. granulosus infection.


Assuntos
Equinococose , Echinococcus granulosus , MicroRNAs , Humanos , Equinococose/imunologia , Equinococose/sangue , Equinococose/parasitologia , Equinococose/genética , MicroRNAs/sangue , MicroRNAs/genética , Projetos Piloto , Echinococcus granulosus/genética , Echinococcus granulosus/imunologia , Animais , Exossomos/genética , Exossomos/imunologia , Exossomos/metabolismo , Imunomodulação , Células Jurkat , Perfilação da Expressão Gênica , Interações Hospedeiro-Parasita/imunologia
4.
Angew Chem Int Ed Engl ; : e202416686, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39327805

RESUMO

Regulating appropriate valence states of metal active centers, such as Ce3+/Ce4+ and Mn3+/Mn2+, as well as surface vacancy defects, is crucial for enhancing the catalytic activity of cerium-based and manganese-based nanozymes. Drawing inspiration from the efficient substance exchange in rhizobia-colonized root cells of legumes, we developed a symbiosis nanozyme system with rhizobia-like nano CeOx clusters robustly anchored onto root-like Mn3O4 nanosupports (CeOx/Mn3O4). The process of "substance exchange" between Ce and Mn atoms-reminiscent of electron transfer-not only fine-tunes the metal active sites to achieve optimal Ce3+/Ce4+ and Mn3+/Mn2+ ratios but also enhances the vacancy ratio through interface defect engineering. Additionally, the confinement anchoring of CeOx on Mn3O4 ensures efficient electron transfer in catalytic reactions. The final CeOx/Mn3O4 nanozyme demonstrates potent catalase-like (CAT- like) and superoxide dismutase-like (SOD-like) activities, excelling in both chemical settings and cellular environments with high reactive oxygen species (ROS) levels. This research not only unveils a novel material adept at effectively eliminating ROS but also presents an innovative approach for amplifying nanozyme efficacy.

5.
Nat Commun ; 15(1): 6972, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143059

RESUMO

Cations such as K+ play a key part in the CO2 electroreduction reaction, but their role in the reaction mechanism is still in debate. Here, we use a highly symmetric Ni-N4 structure to selectively probe the mechanistic influence of K+ and identify its interaction with chemisorbed CO2-. Our electrochemical kinetics study finds a shift in the rate-determining step in the presence of K+. Spectral evidence of chemisorbed CO2- from in-situ X-ray absorption spectroscopy and in-situ Raman spectroscopy pinpoints the origin of this rate-determining step shift. Grand canonical potential kinetics simulations - consistent with experimental results - further complement these findings. We thereby identify a long proposed non-covalent interaction between K+ and chemisorbed CO2-. This interaction stabilizes chemisorbed CO2- and thus switches the rate-determining step from concerted proton electron transfer to independent proton transfer. Consequently, this rate-determining step shift lowers the reaction barrier by eliminating the contribution of the electron transfer step. This K+-determined reaction pathway enables a lower energy barrier for CO2 electroreduction reaction than the competing hydrogen evolution reaction, leading to an exclusive selectivity for CO2 electroreduction reaction.

6.
Food Chem ; 460(Pt 3): 140713, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-39116775

RESUMO

Chitosan, as a kind of naturally occurring green and degradable material for the preservation of perishable foods, was investigated in this study with the objective of enhancing its preservation performances. Herein, lignin was modified using the solvent fractionation method (modified lignin, ML, including ML1-ML3), while natural clinoptilolite zeolite was modified using the alkali modification method (modified clinoptilolite zeolite, MCZ, including MCZ1-MCZ5). After optimizing the conditions, it was discovered that incorporating both ML3 and MCZ3 into pure chitosan-based membranes might be conducive to fabricate chitosan-based composite membranes for the preservation of perishable foods. As-prepared composite membranes possessed better visible light transmittance, antioxidant activity, and carbon dioxide/oxygen selectivity, resulting in improved preservation effects on the model perishable foods such as bananas, cherry tomatoes, and cheeses. These findings might indicate promising applications for chitosan-based composite membranes with modified lignin and zeolite in the field of eco-friendly degradable materials for the preservation of perishable foods.


Assuntos
Quitosana , Conservação de Alimentos , Lignina , Zeolitas , Quitosana/química , Zeolitas/química , Lignina/química , Conservação de Alimentos/métodos , Conservação de Alimentos/instrumentação , Química Verde , Queijo/análise , Antioxidantes/química , Solanum lycopersicum/química , Embalagem de Alimentos/instrumentação
7.
J Inflamm Res ; 17: 5327-5346, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39157587

RESUMO

Purpose: Lichen sclerosus urethral stricture disease (LS USD) is a refractory and progressive disease primarily affecting the anterior urethra in males. Various potential etiological factors, such as genetics, autoimmunity, infection, and exposure to infectious urine, have been suggested. However, the accurate etiology of LS in the male urethra remains unclear. Patients and Methods: In this study, we conducted single-cell RNA sequencing to identify the transcriptional profiles of three patients with LS USD and three patients with non-LS USD. Immunofluorescence was used to confirm the single-cell sequence results. Results: Our study revealed distinct subsets of vein endothelial cells (ECs), smooth muscle cells (SMCs), and fibroblasts (FBs) with high proportions in LS USD, contributing to the tissue microenvironment primarily involved in proinflammatory and immune responses. In particular, FBs displayed a unique subset, Fib7, which is exclusively present in LS USD, and exhibited high expression levels of SAA1 and SAA2. The accumulation of macrophages, along with the dysregulated ratios of M1/M2-like phenotype macrophages, may be engaged in the pathogenesis of LS USD. Through cell-cell communication analysis, we identified significant interactions involving CXCL8/ACKR1 and CCR7/CCL19 in LS USD. Remarkably, Fib7 exhibited exclusive communication with IL-1B macrophages through the SAA1/FPR2 receptor-ligand pair. Conclusion: Our study provides a profound understanding of the tissue microenvironment in LS USD, which may be valuable for understanding the pathogenesis of LS USD.

8.
Crit Rev Immunol ; 44(6): 75-85, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38848295

RESUMO

Laryngeal cancer (LC) is a prevailing tumor with a high mortality rate. The pivotal role of mitophagy in LC is acknowledged; however, a comprehensive analysis of the corresponding genes has not been conducted. In the present study, we proposed a prognostic model consisting of mitophagy-related genes in LC. Clinical information and transcriptome profiling of patients with LC and mitophagy-related genes were retrieved from open-source databases. Gene set variation analysis (GSVA) and Weighted Gene Co-expression Network Analysis (WGCNA) were used to identify core mitophagy-related genes and construct gene co-expression networks. Functional enrichment analysis was employed to analyze the enriched regulatory pathways of the mitophagy-related genes. Kaplan-Meier curves (KM), Cox, and LASSO regression were applied to explore their prognostic effects. Finally, quantitative real-time PCR (RT-qPCR) further verified the bioinformatics prediction. A total of 45 genes related to mitochondrial pathways was collected. GSVA analysis demonstrated that these genes in tumor samples mainly referred to the mitochondrial pathway. Among these genes, five mitophagy-related-gene signatures (CERCAM, CHPF, EPHX3, EXT2, and MED15) were further identified to construct the prognostic model. KM and Cox regression analyses indicated that this model had an accurate prognostic prediction for LC. RT-qPCR showed that CERCAM, CHPF, EXT2, and MED15 expression were upregulated, and EPHX3 level was decreased in LC cells. The present study established a five-mitophagy-related-gene model that can predict the prognosis of LC patients, thus laying the foundation for a better understanding and potential advancements in clinical treatments for LC.


Assuntos
Biomarcadores Tumorais , Biologia Computacional , Regulação Neoplásica da Expressão Gênica , Neoplasias Laríngeas , Mitofagia , Humanos , Mitofagia/genética , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/mortalidade , Biologia Computacional/métodos , Prognóstico , Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Transcriptoma
9.
Prev Med Rep ; 42: 102741, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38721570

RESUMO

Background: The purpose of this study was to examine the relationship between sleep duration and risk of sarcopenia in in general U.S. population. Methods: Utilizing publicly available data from the National Health and Nutrition Examination Survey spanning from 2011 to 2014, we explored the association between sleep duration and prevalence of sarcopenia. To investigate their relationship, we conducted weighted multivariate logistic regression analysis, restricted cubic splines (RCS) curve, and subgroup analysis. Results: The study included 8,200 individuals, among whom 99 (0.9 %) had sarcopenia. The RCS curve revealed a U-shaped association of sarcopenia with sleep duration (P for nonlinearity = 0.020), showing that the risk of sarcopenia decreases with increasing sleep duration, reaching the lowest risk around 6.67 h. After controlling for underlying cofounders, compared to individuals with sleep duration < 5 h, the odds ratios with 95 % confidence intervals of sarcopenia were 0.64 (0.27, 1.49), 0.50 (0.20, 1.26), 0.65 (0.27, 1.60), and 2.31 (0.73, 7.30) for < 5-6, 6.5-7.5, 8-9, and > 9 h group. The U-shaped association between sleep time and prevalence of sarcopenia also was observed in the subjects who aged < 40 or ≥ 40 years, were male or female, with or without hypertension, and diabetes mellitus. Conclusions: In summary, both short and long sleep durations increased prevalence of sarcopenia. Further studies are needed to explore the underlying mechanisms.

10.
Angew Chem Int Ed Engl ; 63(29): e202404568, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38696242

RESUMO

Few-atom metal clusters (FAMCs) exhibit superior performance in catalyzing complex molecular transformations due to their special spatial environments and electronic states, compared to single-atom catalysts (SACs). However, achieving the efficient and accurate synthesis of FAMCs while avoiding the formation of other species, such as nanoparticles and SACs, still remains challenges. Herein, we report a two-step strategy for synthesis of few-atom platinum (Pt) clusters by predeposition of zinc single-atom-glue (Zn1) on MgO nanosheets (Ptn-Zn1/MgO), where FAMCs can be obtained over a wide range of Pt contents (0.09 to 1.45 wt %). Zn atoms can act as Lewis acidic sites to allow electron transfer between Zn and Pt through bridging O atoms, which play a crucial role in the formation and stabilization of few-atom Pt clusters. Ptn-Zn1/MgO exhibited a high selectivity of 93 % for anti-Markovnikov alkene hydrosilylation. Moreover, an excellent activity with a turnover frequency of up to 1.6×104 h-1 can be achieved, exceeding most of the reported Pt SACs. Further theoretical studies revealed that the Pt atoms in Ptn-Zn1/MgO possess moderate steric hindrance, which enables high selectivity and activity for hydrosilylation. This work presents some guidelines for utilizing atomic-scale species to increase the synthesis efficiency and precision of FAMCs.

11.
ACS Omega ; 9(8): 9728-9734, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434882

RESUMO

The distribution of gas and water in the tight gas reservoirs is complex. This limits exploration and development compared to conventional resources. Elucidating the characteristics that control fluid distribution is critical to unlocking the tight gas potential. This study combines geologic analysis with production data to reveal the water chemistry, gas-water distribution, and factors controlling zoning in the study area. The results show that (a) extracted water includes formation brines, condensate, and residual drilling fluids; (b) formation water dominates production, and the salinity of Lower Paleozoic brines is as high as 169,689 mg/L; (c) low NaCl and high metamorphic coefficients indicate that the water bodies are disconnected and the hydrocarbons are well-preserved in several gas-water systems; and (d) paleomorphological features, tectonics, and lithologies control the distribution of gas water. Discrete water bodies are widely distributed.

12.
iScience ; 27(2): 109008, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38352228

RESUMO

Disruption of circadian rhythms during fetal development may predispose mice to developing heart disease later in life. Here, we report that male, but not female, mice that had experienced chronic circadian disturbance (CCD) in utero were more susceptible to pathological cardiac remodeling compared with mice that had developed under normal intrauterine conditions. CCD-treated males showed ventricular chamber dilatation, enhanced myocardial fibrosis, decreased contractility, higher rates of induced tachyarrhythmia, and elevated expression of biomarkers for heart failure and myocardial remodeling. In utero CCD exposure also triggered sex-dependent changes in cardiac gene expression, including upregulation of the secretoglobin gene, Scgb1a1, in males. Importantly, cardiac overexpression of Scgb1a1 was sufficient to induce myocardial hypertrophy in otherwise naive male mice. Our findings reveal that in utero CCD exposure predisposes male mice to pathological remodeling of the heart later in life, likely as a consequence of SCGB1A1 upregulation.

13.
Sci Total Environ ; 913: 169720, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38171457

RESUMO

Over the past decades, considerable efforts have been made to find useful solutions for phosphate pollution control. The state transition of nanomaterials from freely dispersed to encapsulated provides a realizable route for their application in phosphate elimination. The separation convenience offered by encapsulation has been widely recognized, however, the unique binding mode of nanostructures and phosphate in the confined space remains unclear, limiting its further development. Here, carboxymethyl cellulose (CMC) microspheres were used as hosts to deploy layered double hydroxide (LDH) nanoparticles. On this basis, we described an attempt to explore the adsorption behavior of LDH and phosphate in the microsphere space. Compared to their freely dispersed analogues, LDH particles exhibited higher structural stability, wider pH adaptability, and better phosphate selectivity when spatially confined in the CMC microsphere. Nevertheless, the kinetic process was severely inhibited by three orders of magnitude. Besides, the saturated phosphate adsorption capacity was also reduced to 74.6 % of the freely dispersed system. A combinative characterization revealed that the highly electronegative CMC host not only causes electrostatic repulsion to phosphate, but also extracts the electron density of the metal center of LDH, weakening its ability to act as a Lewis acid site for phosphate binding. Meanwhile, the microsphere encapsulation also hinders the ion exchange function of interlayer anions and phosphate. This study offers an objective insight into the reaction of LDH and phosphate in the confined microsphere space, which may contribute to the advanced design of encapsulation strategies for nanoparticles.

14.
Microbiol Res ; 280: 127590, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142517

RESUMO

The detrimental impact of soil salinization on crop productivity and agricultural economy has garnered significant attention. A rhizosphere bacterium with favorable salt tolerance and plant growth-promoting (PGP) functions was isolated in this work. The bacterium was identified as Enterobacter through 16 S rDNA sequencing analysis and designated as Enterobacter sp. JIV1. Interestingly, the presence of putrescine (Put), which had been shown to contribute in reducing abiotic stress damage to plants, significantly promoted strain JIV1 to generate 1-aminocyclopropane-1-carboxylic (ACC) deaminase, dissolve phosphorus and secrete indole-3-acetic acid (IAA). However, the synergy of plant growth promoting rhizobacteria (PGPR) and Put in improving plant salt resistance has not been extensively studied. In this study, strain JIV1 and exogenous Put effectively mitigated the inhibitory impact of salt stress simulated by 200 mM NaCl on rice (Oryza sativa L.) growth. The chlorophyll accumulation, photosynthetic efficiency and antioxidant capacity of rice were also significantly strengthened. Notably, the combined application of strain JIV1 and Put outperformed individual treatments. Moreover, the co-addition of strain JIV1 and Put increased soil protease and urease activities by 451.97% and 51.70% compared to that of salt treatment group. In general, Put-assisted PGPR JIV1 provides a new perspective on alleviating the salt-induced negative impacts on plants.


Assuntos
Enterobacter , Oryza , Solo , Oryza/microbiologia , Putrescina , Estresse Salino , Oxirredução
15.
Proc Natl Acad Sci U S A ; 120(52): e2310916120, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38117856

RESUMO

The kinetics and pathway of most catalyzed reactions depend on the existence of interface, which makes the precise construction of highly active single-atom sites at the reaction interface a desirable goal. Herein, we propose a thermal printing strategy that not only arranges metal atoms at the silica and carbon layer interface but also stabilizes them by strong coordination. Just like the typesetting of Chinese characters on paper, this method relies on the controlled migration of movable nanoparticles between two contact substrates and the simultaneous emission of atoms from the nanoparticle surface at high temperatures. Observed by in situ transmission electron microscopy, a single Fe3O4 nanoparticle migrates from the core of a SiO2 sphere to the surface like a droplet at high temperatures, moves along the interface of SiO2 and the coated carbon layer, and releases metal atoms until it disappears completely. These detached atoms are then in situ trapped by nitrogen and sulfur defects in the carbon layer to generate Fe single-atom sites, exhibiting excellent activity for oxygen reduction reaction. Also, sites' densities can be regulated by controlling the size of Fe3O4 nanoparticle between the two surfaces. More importantly, this strategy is applicable to synthesize Mn, Co, Pt, Pd, Au single-atom sites, which provide a general route to arrange single-atom sites at the interface of different supports for various applications.

16.
Inorg Chem ; 62(46): 19123-19134, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37945002

RESUMO

Electrochemical hydrogeneration (ECH) of biomass-derived platform molecules, which avoids the disadvantages in utilizing fossil fuel and gaseous hydrogen, is a promising route toward value-added chemicals production. Herein, we reported a CoO/Co heterostructure-supported Pt single atoms electrocatalyst (Pt1-CoO/Co) that exhibited an outstanding performance with a high conversion (>99%), a high Faradaic efficiency (87.6%), and robust stability (24 recyclability) at -20 mA/cm2 for electrochemical phenol hydrogenation to high-valued KA oil (a mixture of cyclohexanol and cyclohexanone). Experimental results and the density functional theory calculations demonstrated that Pt1-CoO/Co presented strong adsorption of phenol and hydrogen on the catalyst surface simultaneously, which was conducive to the transfer of the adsorbed hydrogen generated on the single atom Pt sites to activated phenol, and then, ECH of phenol with high performance was achieved instead of the direct hydrogen evolution reaction. This work described that the multicomponent synergistic single atom catalysts could effectively accelerate the ECH of phenol, which could help the achievement of large-scale biomass upgrading.

17.
J Environ Manage ; 348: 119408, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37879180

RESUMO

Sulfamethoxazole (SMX) has been widely detected in various environments and its potential environmental risks have caused great concerns. However, the impact mechanism of SMX on microbial interactions among anammox consortia remain unknown. A long-term exposure experiments (140 d) was carried out to systematically examine the influence of SMX (0-1000 µg/L) on the anammox system, especially microbial network dynamics and variations of key metabolic genes. Results showed that anammox system could adapt to SMX below 500 µg/L and maintain a high nitrogen removal efficiency (NRE) of 85.35 ± 2.42%, while 1000 µg/L SMX significantly decreased the abundance of functional microbes and deteriorated denitrification performance with NRE dropped to 36.92 ± 15.01%. Co-occurrence network analysis indicated that 1000 µg/L SMX decreased the interactions between Proteobacteria and Chloroflexi and limited AnAOB from playing an important role as central nodes in the subnetwork of Planctomycetes. Metagenomics analysis found that genes associated with nitrogen removal (i.e., hdh, hzs, nirS, and hao) showed lower expression level after addition of SMX, while SMX-related ARGs (sul1 and sul2) increased by 1.22 and 2.68 times. This study provided us a relatively comprehensive perspective in response of microbial interactions and metabolic activity to various SMX concentrations.


Assuntos
Oxidação Anaeróbia da Amônia , Sulfametoxazol , Sulfametoxazol/farmacologia , Nitrogênio , Interações Microbianas
18.
Nat Commun ; 14(1): 5338, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660124

RESUMO

Cells possess isolated compartments that spatially confine different enzymes, enabling high-efficiency enzymatic cascade reactions. Herein, we report a cell-inspired design of biomimetic cascade catalysis system by immobilizing Fe single atoms and Au nanoparticles on the inner and outer layers of three-dimensional nanocapsules, respectively. The different metal sites catalyze independently and work synergistically to enable engineered and cascade glucose detection. The biomimetic catalysis system demonstrates ~ 9.8- and 2-fold cascade activity enhancement than conventional mixing and coplanar construction systems, respectively. Furthermore, the biomimetic catalysis system is successfully demonstrated for the colorimetric glucose detection with high catalytic activity and selectivity. Also, the proposed gel-based sensor is integrated with smartphone to enable real-time and visual determination of glucose. More importantly, the gel-based sensor exhibits a high correlation with a commercial glucometer in real samples detection. These findings provide a strategy to design an efficient biomimetic catalysis system for applications in bioassays and nanobiomedicines.


Assuntos
Ouro , Nanopartículas Metálicas , Domínio Catalítico , Catálise , Glucose
19.
Toxics ; 11(7)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37505600

RESUMO

Due to rapidly expanding crayfish consumption worldwide, the food safety of red swamp crayfish (Procambarus clarkii) is of great concern. China is the largest consumer and producer of crayfish globally. As of yet, it is unknown whether the main crayfish production cities in China are within safe levels of toxic heavy metals and metalloids. For 16 consecutive years, Qianjiang city ranked first in China in processing export volumes of red swamp crayfish. This study presents a comprehensive analysis of the enrichment levels and associated health risks of the species in Qianjiang. In our research, samples of four crayfish tissues, including the head, hepatopancreas, gills, and muscles, were collected from 38 sampling sites distributed in Qianjiang to evaluate the concentration levels of five heavy metals (Pb, Hg, Cd, As, and Cu). The concentration levels of all five metals in muscle did not surpass the national standard. Furthermore, eight significant correlations have been found. For further in-depth assess risk of crayfish in Qianjiang, estimated daily intake (EDI), target hazard quotient (THQ), carcinogenic risk (CR), and estimated maximum allowable consumption rates (CRmm) were evaluated in the abdomen muscle and hepatopancreas. The THQ values for each metal were found to be less than 1, while the CR values were below 10-6. Additionally, the CRmm for adults was determined to be 17.2 meals per month. These findings, based on the analysis of five metallic elements included in this study, suggest that the consumption of crayfish abdomen muscle in Qianjiang does not pose any significant health risks. However, it is noteworthy that certain regions exhibit elevated levels of arsenic in the hepatopancreas, surpassing the national standard, thereby rendering them unsuitable for excessive consumption. In general, the findings can be used to provide guidance for safe dietary practices in China.

20.
Small ; 19(45): e2302328, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37431211

RESUMO

The design of an efficient catalytic system with low Pt loading and excellent stability for the acidic oxygen reduction reaction is still a challenge for the extensive application of proton-exchange membrane fuel cells. Here, a gas-phase ordered alloying strategy is proposed to construct an effective synergistic catalytic system that blends PtM intermetallic compounds (PtM IMC, M = Fe, Cu, and Ni) and dense isolated transition metal sites (M-N4 ) on nitrogen-doped carbon (NC). This strategy enables Pt nanoparticles and defects on the NC support to timely trap flowing metal salt without partial aggregation, which is attributed to the good diffusivity of gaseous transition metal salts with low boiling points. In particular, the resulting Pt1 Fe1 IMC cooperating with Fe-N4 sites achieves cooperative oxygen reduction with a half-wave potential up to 0.94 V and leads to a high mass activity of 0.51 A  mgPt -1 and only 23.5% decay after 30 k cycles, both of which exceed DOE 2025 targets. This strategy provides a method for reducing Pt loading in fuel cells by integrating Pt-based intermetallics and single transition metal sites to produce an efficient synergistic catalytic system.

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