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1.
J Am Chem Soc ; 146(22): 15393-15402, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38767283

RESUMEN

Quinone-based electrodes using carbonyl redox reactions are promising candidates for aqueous energy storage due to their high theoretical specific capacity and high-rate performance. However, the proton storage manners and their influences on the electrochemical performance of quinone are still not clear. Herein, we reveal that proton storage could determine the products of the enol conversion and the electrochemical stability of the organic electrode. Specifically, the protons preferentially coordinated with the prototypical pyrene-4,5,9,10-tetraone (PTO) cathode, and increasing the proton concentration in the electrolyte can improve its working potentials and cycling stability by tailoring the enol conversion reaction. We also found that exploiting Al2(SO4)3 as a pH buffer can increase the energy density of the Zn||PTO batteries from 242.8 to 284.6 Wh kg-1. Our research has a guiding significance for emphasizing proton storage of organic electrodes based on enol conversion reactions and improving their electrochemical performance.

2.
J Am Chem Soc ; 146(28): 18967-18978, 2024 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-38973592

RESUMEN

Platensilin, platensimycin, and platencin are potent inhibitors of ß-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 µg/mL) against S. aureus compared to platensimycin.


Asunto(s)
Adamantano , Aminobenzoatos , Aminofenoles , Anilidas , Compuestos Policíclicos , Aminofenoles/química , Aminofenoles/farmacología , Aminofenoles/síntesis química , Compuestos Policíclicos/química , Compuestos Policíclicos/farmacología , Compuestos Policíclicos/síntesis química , Adamantano/química , Adamantano/farmacología , Adamantano/síntesis química , Adamantano/análogos & derivados , Anilidas/farmacología , Anilidas/química , Anilidas/síntesis química , Aminobenzoatos/farmacología , Aminobenzoatos/química , Aminobenzoatos/síntesis química , Antibacterianos/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Staphylococcus aureus/efectos de los fármacos , Estructura Molecular , Reacción de Cicloadición , Pruebas de Sensibilidad Microbiana , Estereoisomerismo , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/química
3.
Small ; : e2404538, 2024 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-39105463

RESUMEN

Diabetic wounds are characterized by the disruption and cessation of essential healing stages, which include hemostasis, inflammation, proliferation, and remodeling. However, traditional treatments for diabetic wounds concentrate on individual stages of the healing process. Herein, this study utilizes mask-mediated sequential polymerization and varied cross-linking techniques to develop dual-modular microneedles (MNs) with fast- and slow-module, exhibiting varying degradation rates tailored for the full spectrum of diabetic wound healing. First, MNs incorporating calcium ions and dopamine synergistically promote rapid hemostasis. Second, fast-module physically cross-linked MNs rapidly D-mannose/dopamine-enhanced tripolyphosphate-quaternized chitosan (mDTC) nanoparticles (NPs) loaded with microRNA-147 (miRNA-147) to manage inflammation and oxidative stress in diabetic wounds. Additionally, dopamine in these NPs enhances their internalization and safeguards miRNA-147 from oxidative stress and RNase degradation. Finally, slow-module chemically cross-linked MNs facilitate the continuous release of deferoxamine (DFO) and dopamine, accelerating angiogenesis and tissue regeneration during the proliferation and remodeling stages. Manganese/dopamine-enhanced calcium peroxide NPs within the MNs initiate a blast-like generation of oxygen bubbles, not only enhancing the delivery of miRNA-mDTC NPs and DFO but also alleviating tissue hypoxia. Consequently, dual-modular MNs are instrumental in promoting rapid and complete healing of diabetic wounds through all stages of healing.

4.
J Chem Inf Model ; 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38949724

RESUMEN

Ameliorating microglia-mediated neuroinflammation is a crucial strategy in developing new drugs for neurodegenerative diseases. Plant compounds are an important screening target for the discovery of drugs for the treatment of neurodegenerative diseases. However, due to the spatial complexity of phytochemicals, it becomes particularly important to evaluate the effectiveness of compounds while avoiding the mixing of cytotoxic substances in the early stages of compound screening. Traditional high-throughput screening methods suffer from high cost and low efficiency. A computational model based on machine learning provides a novel avenue for cytotoxicity determination. In this study, a microglia cytotoxicity classifier was developed using a machine learning approach. First, we proposed a data splitting strategy based on the molecule murcko generic scaffold, under this condition, three machine learning approaches were coupled with three kinds of molecular representation methods to construct microglia cytotoxicity classifier, which were then compared and assessed by the predictive accuracy, balanced accuracy, F1-score, and Matthews Correlation Coefficient. Then, the recursive feature elimination integrated with support vector machine (RFE-SVC) dimension reduction method was introduced to molecular fingerprints with high dimensions to further improve the model performance. Among all the microglial cytotoxicity classifiers, the SVM coupled with ECFP4 fingerprint after feature selection (ECFP4-RFE-SVM) obtained the most accurate classification for the test set (ACC of 0.99, BA of 0.99, F1-score of 0.99, MCC of 0.97). Finally, the Shapley additive explanations (SHAP) method was used in interpreting the microglia cytotoxicity classifier and key substructure smart identified as structural alerts. Experimental results show that ECFP4-RFE-SVM have reliable classification capability for microglia cytotoxicity, and SHAP can not only provide a rational explanation for microglia cytotoxicity predictions, but also offer a guideline for subsequent molecular cytotoxicity modifications.

5.
Environ Sci Technol ; 58(12): 5430-5441, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38471097

RESUMEN

The evaporative emissions of anthropogenic volatile organic compounds (AVOCs) are sensitive to ambient temperature. This sensitivity forms an air pollution-meteorology connection that has not been assessed on a regional scale. We parametrized the temperature dependence of evaporative AVOC fluxes in a regional air quality model and evaluated the impacts on surface ozone in the Beijing-Tianjin-Hebei (BTH) area of China during the summer of 2017. The temperature dependency of AVOC emissions drove an enhanced simulated ozone-temperature sensitivity of 1.0 to 1.8 µg m-3 K-1, comparable to the simulated ozone-temperature sensitivity driven by the temperature dependency of biogenic VOC emissions (1.7 to 2.4 µg m-3 K-1). Ozone enhancements driven by temperature-induced AVOC increases were localized to their point of emission and were relatively more important in urban areas than in rural regions. The inclusion of the temperature-dependent AVOC emissions in our model improved the simulated ozone-temperature sensitivities on days of ozone exceedance. Our results demonstrated the importance of temperature-dependent AVOC emissions on surface ozone pollution and its heretofore unrepresented role in air pollution-meteorology interactions.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Ozono , Compuestos Orgánicos Volátiles , Ozono/análisis , Contaminantes Atmosféricos/análisis , Compuestos Orgánicos Volátiles/análisis , Temperatura , Monitoreo del Ambiente/métodos , China
6.
Bioorg Chem ; 147: 107335, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38583250

RESUMEN

Fifty compounds including seven undescribed (1, 13, 18-20, 30, 31) and forty-three known (2-12, 14-17, 21-29, 32-50) ones were isolated from the extract of the twigs and leaves of Aglaia odorata with anti-neuroinflammatory activities. Their structures were determined by a combination of spectral analysis and calculated spectra (ECD and NMR). Among them, compounds 13-25 were found to possess tertiary amide bonds, with compounds 16, 17, and 19-21 existing detectable cis/trans mixtures in 1H NMR spectrum measured in CDCl3. Specifically, the analysis of the cis-trans isomerization equilibrium of tertiary amides in compounds 19-24 was conducted using NMR spectroscopy and quantum chemical calculations. Bioactivity evaluation showed that the cyclopenta[b]benzofuran derivatives (2-6, 8, 10, 12) could inhibit nitric oxide production at the nanomolar concentration (IC50 values ranging from 2 to 100 nM) in lipopolysaccharide-induced BV-2 cells, which were 413-20670 times greater than that of the positive drug (minocycline, IC50 = 41.34 µM). The cyclopenta[bc]benzopyran derivatives (13-16), diterpenoids (30-35), lignan (40), and flavonoids (45, 47, 49, 50) also demonstrated significant inhibitory activities with IC50 values ranging from 1.74 to 38.44 µM. Furthermore, the in vivo anti-neuroinflammatory effect of rocaglaol (12) was evaluated via immunofluorescence, qRT-PCR, and western blot assays in the LPS-treated mice model. The results showed that rocaglaol (12) attenuated the activation of microglia and decreased the mRNA expression of iNOS, TNF-α, IL-1ß, and IL-6 in the cortex and hippocampus of mice. The mechanistic study suggested that rocaglaol might inhibit the activation of the NF-κB signaling pathway to relieve the neuroinflammatory response.


Asunto(s)
Aglaia , Lipopolisacáridos , Óxido Nítrico , Animales , Ratones , Aglaia/química , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Estructura Molecular , Relación Estructura-Actividad , Relación Dosis-Respuesta a Droga , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Masculino , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/aislamiento & purificación , Benzofuranos/farmacología , Benzofuranos/química , Benzofuranos/aislamiento & purificación , Línea Celular , Hojas de la Planta/química
7.
Bioorg Chem ; 149: 107484, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38810482

RESUMEN

A total of 37 characteristic terpenylated coumarins (1-25), including 17 undescribed compounds (1-5, 6a/6b, 7-10, 11a/11b-13a/13b), have been isolated from the root of Ferula ferulaeoides. Meanwhile, twelve pairs of enantiomers (6a/6b, 11a/11b-15a/15b, 17a/17b, 18a/18b, 20a/20b-22a/22b, and 25a/25b) were chirally purified. The structures of these new compounds were elucidated using HRESIMS, UV, NMR, and calculated 13C NMR with a custom DP4 + analysis. The absolute configurations of all the compounds were determined for the first time using electronic circular dichroism (ECD). Then, their inhibitory effects on nitric oxide (NO) production were evaluated with LPS-induced BV-2 microglia. Compared with the positive control minocycline (IC50 = 59.3 µM), ferulaferone B (2) exhibited stronger inhibitory potency with an IC50 value of 12.4 µM. The immunofluorescence investigation indicated that ferulaferone B (2) could inhibit Iba-1 expression in LPS-stimulated BV-2 microglia.


Asunto(s)
Cumarinas , Relación Dosis-Respuesta a Droga , Ferula , Lipopolisacáridos , Microglía , Óxido Nítrico , Cumarinas/farmacología , Cumarinas/química , Cumarinas/aislamiento & purificación , Ferula/química , Microglía/efectos de los fármacos , Microglía/metabolismo , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Animales , Estructura Molecular , Ratones , Relación Estructura-Actividad , Lipopolisacáridos/farmacología , Lipopolisacáridos/antagonistas & inhibidores , Raíces de Plantas/química
8.
Bioorg Chem ; 150: 107570, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38941695

RESUMEN

Axially chiral compounds are well known in medicinal chemistry of natural products, but their absolute configurations and bioactivities are rarely reported and studied. In this study, eleven undescribed axially chiral dihydrophenanthrene dimers, as well as twenty-five known dihydrophenanthrenes, were isolated from the entire plant of Pholidota yunnanensis. Their structures were elucidated by comprehensive spectroscopic analysis. A method for determining the absolute configurations of enantiomers was developed based on the rotational barriers and calculated ECD spectra. Additionally, the activities of all isolated compounds were assessed in LPS-induced BV-2 microglial cells. Most dihydrophenanthrenes exhibited significant NO inhibitory activities, and compound 7 showed the most potent inhibitory effect with an IC50 value of 1.5 µM, compared to the positive control minocycline. The immunofluorescence and western blot results revealed that compound 7 suppressed the expression of Iba-1, iNOS and COX-2 in LPS-stimulated BV-2 microglial cells.


Asunto(s)
Lipopolisacáridos , Microglía , Fenantrenos , Fenantrenos/farmacología , Fenantrenos/química , Fenantrenos/aislamiento & purificación , Animales , Ratones , Lipopolisacáridos/antagonistas & inhibidores , Lipopolisacáridos/farmacología , Estructura Molecular , Microglía/efectos de los fármacos , Microglía/metabolismo , Relación Estructura-Actividad , Dimerización , Relación Dosis-Respuesta a Droga , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Óxido Nítrico/metabolismo , Orchidaceae/química , Línea Celular , Antiinflamatorios/farmacología , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/aislamiento & purificación , Estereoisomerismo
9.
Acta Pharmacol Sin ; 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112770

RESUMEN

Cyclic GMP-AMP synthase (cGAS) is a major cytosolic DNA sensor that plays a significant role in innate immunity. Upon binding to double stranded DNA (dsDNA), cGAS utilizes GTP and ATP to synthesize the second messenger cyclic GMP-AMP (cGAMP). The cGAMP then binds to the adapter protein stimulator of interferon genes (STING) in the endoplasmic reticulum, resulting in the activation of the transcription factor interferon regulatory factor 3 (IRF3) and subsequent induction of type I interferon. An important question is how cGAS distinguishes between self and non-self DNA. While cGAS binds to the phosphate backbone of DNA without discrimination, its activation is influenced by physical features such as DNA length, inter-DNA distance, and mechanical flexibility. This suggests that the recognition of DNA by cGAS may depend on these physical features. In this article we summarize the recent progress in research on cGAS-STING pathway involved in antiviral defense, cellular senescence and anti-tumor response, and focus on DNA recognition mechanisms based on the physical features.

10.
Environ Res ; 256: 119237, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38810829

RESUMEN

Ionizing radiation (IR) poses a significant threat to both the natural environment and biological health. Exposure to specific doses of ionizing radiation early in an organism's development can lead to developmental toxicity, particularly neurotoxicity. Through experimentation with Xenopus laevis (X. laevis), we examined the effects of radiation on early developmental stage. Our findings revealed that radiation led to developmental abnormalities and mortality in X. laevis embryos in a dose-dependent manner, disrupting redox homeostasis and inducing cell apoptosis. Additionally, radiation caused neurotoxic effects, resulting in abnormal behavior and neuron damage in the embryos. Further investigation into the underlying mechanisms of radiation-induced neurotoxicity indicated the potential involvement of the neuroactive ligand-receptor interaction pathway, which was supported by RNA-Seq analysis. Validation of gene expression associated with this pathway and analysis of neurotransmitter levels confirmed our hypothesis. In addition, we further validated the important role of this signaling pathway in radiation-induced neurotoxicity through edaravone rescue experiments. This research establishes a valuable model for radiation damage studying and provides some insight into radiation-induced neurotoxicity mechanisms.


Asunto(s)
Embrión no Mamífero , Radiación Ionizante , Xenopus laevis , Animales , Embrión no Mamífero/efectos de la radiación , Síndromes de Neurotoxicidad/etiología , Transducción de Señal/efectos de la radiación , Apoptosis/efectos de la radiación , Ligandos
11.
Clin Rehabil ; : 2692155241232399, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38794843

RESUMEN

OBJECTIVES: To evaluate the efficacy of exercise in improving body composition in patients with breast cancer; the effects of exercise on weight and BMI were evaluated as secondary outcomes. DATA SOURCES: Cochrane Library, EMBASE, PubMed and Web of Science were searched for randomized controlled trials published in English from database inception to 29 November 2023. METHODS: The effects of exercise on body composition in patients with breast cancer were explored. After separately extracting the data, two reviewers assessed the overall quality of the evidence as well as the methodological quality of the included studies. RESULTS: Fourteen studies with 1241 participants were included, of which 12 studies were eligible for meta-analysis. Exercise significantly reduced body fat (mean difference [MD], -0.33; 95% CI, -0.37 to -0.29; P < 0.00001) and increased lean mass (MD, 0.42; 95% CI, 0.34 to 0.49; P < 0.00001) in patients with breast cancer. Further, exercise intervention was associated with increased BMI of patients with breast cancer (MD, 0.03; 95% CI, 0.01 to 0.06; P = 0.01), while no significant difference in weight was detected between the exercise and the non-exercise groups. Subgroup analysis results showed that only resistance exercise reduced fat mass (MD, -0.22; 95% CI, -0.27 to -0.16; P < 0.00001). CONCLUSIONS: Exercise effectively improves body composition in patients with breast cancer. Clinicians should encourage patients to engage in exercise and develop optimized exercise prescriptions.

12.
Phytother Res ; 38(8): 4286-4306, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38973314

RESUMEN

Tamarixetin, a natural dietary flavone, exhibits remarkable potential for the treatment of ischemic stroke. The present article aimed to explore the impact of tamarixetin on ischemic stroke and elucidate the underlying mechanisms. Effects of tamarixetin on ischemic stroke were evaluated in rats using the middle cerebral artery occlusion and reperfusion (MCAO/R) model, by assessing the neurological deficit scores, brain water content, brain infraction, and neuronal damage. The levels of proinflammatory cytokines, NLRP3 inflammasome activation, reactive oxygen species (ROS) production, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression were measured in MCAO/R rats and lipopolysaccharide-stimulated cells. Tamarixetin administration improved the neurological dysfunction and neuronal loss in MCAO/R rats. In addition, tamarixetin reduced microglial hyperactivation and proinflammatory cytokines expression in vivo and in vitro. Tamarixetin attenuated NF-κB p65 phosphorylation and promoter activity, reduced NLRP3 expression and caspase-1 cleavage, and downregulated IL-1ß and IL-18 secretions to suppress NLRP3 inflammasome activation. The levels of superoxide anion, hydrogen peroxide, and ROS were also suppressed by tamarixetin. The downregulation of NADP+ and NADPH levels, and gp91phox expression indicated the ameliorative effects of tamarixetin on NADPH oxidase activation. In the gp91phox knockdown cells treated with lipopolysaccharide, the effects of tamarixetin on NADPH oxidase activation, ROS generation, and NLRP3 inflammasome activation were diminished. Moreover, tamarixetin protects neurons against microglial hyperactivation in vitro. Our findings support the potential of tamarixetin as a therapeutic agent for ischemic stroke, and its mechanism of action involves the inhibition of NADPH oxidase-NLRP3 inflammasome signaling.


Asunto(s)
Disacáridos , Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno , Daño por Reperfusión , Animales , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Ratas , Daño por Reperfusión/tratamiento farmacológico , Masculino , Inflamasomas/metabolismo , Disacáridos/farmacología , Especies Reactivas de Oxígeno/metabolismo , NADPH Oxidasa 2/metabolismo , NADPH Oxidasas/metabolismo , Microglía/efectos de los fármacos , Microglía/metabolismo , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Modelos Animales de Enfermedad , Isquemia Encefálica/tratamiento farmacológico , Quercetina/análogos & derivados
13.
J Asian Nat Prod Res ; : 1-8, 2024 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-38234138

RESUMEN

An anti-neuroinflammatory activities-guided phytochemical research of Wikstroemia lungtzeensis was performed for the first time. Three undescribed carotane-type sesquiterpenes, excoecafolinols C-E (1-3), and nine known sesquiterpene derivatives were isolated from the effective ethyl acetate extract of W. lungtzeensis. Their structures were determined based on multiple spectroscopic techniques and electronic circular dichroism (ECD) spectra. Furthermore, the anti-neuroinflammatory activities of the identified compounds were evaluated in lipopolysaccharide-stimulated BV-2 cells. Among them, six components (1, 2, 4, 7, 11, 12) exhibited significant inhibitory effects on nitric oxide (NO) production, with IC50 values ranging from 10.48 to 49.41 µM (positive control minocycline, IC50 53.20 µM). Carotane-type sesquiterpenes (1, 2, 4) with high content and significant inhibitory effects, are considered to be major active ingredients of W. lungtzeensis, which might serve as potential therapeutic agents for neurodegenerative diseases.

14.
Geriatr Nurs ; 59: 687-693, 2024 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-39216260

RESUMEN

Older spousal caregivers bear the dual burden of managing health changes and caring for their partners. This study aimed to investigate the association between spousal caregiving and frailty in older adults. A retrospective cohort study with a 4-year follow-up was conducted using seven waves of data from the Health and Retirement Study (2006-2018). The mean age of participants was 65.1 years. A significant correlation was found between spousal caregiving and frailty increase. Multilevel analysis demonstrated a significant difference in the changes in frailty index over 12 years between caregivers and non-caregivers. This study uncovered a significant association between spousal caregiving and frailty in older adults, suggesting that becoming a spousal caregiver is not only linked to higher levels of frailty but also accelerates its progression. Healthcare providers can tailor support services to assist caregivers in managing challenges and promoting healthy aging.

15.
Angew Chem Int Ed Engl ; 63(35): e202407589, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-38703065

RESUMEN

Directly electrochemical conversion of nitrate (NO3 -) is an efficient and environmentally friendly technology for ammonia (NH3) production but is challenged by highly selective electrocatalysts. High-entropy alloys (HEAs) with unique properties are attractive materials in catalysis, particularly for multi-step reactions. Herein, we first reported the application of HEA (FeCoNiAlTi) for electrocatalytic NO3 - reduction to NH3 (NRA). The bulk HEA is active for NRA but limited by the unsatisfied NH3 yield of 0.36 mg h-1 cm-2 and Faradaic efficiency (FE) of 82.66 %. Through an effective phase engineering strategy, uniform intermetallic nanoparticles are introduced on the bulk HEA to increase electrochemical active surface area and charge transfer efficiency. The resulting nanostructured HEA (n-HEA) delivers enhanced electrochemical NRA performance in terms of NH3 yield (0.52 mg h-1 cm-2) and FE (95.23 %). Further experimental and theoretical investigations reveal that the multi-active sites (Fe, Co, and Ni) dominated electrocatalysis for NRA over the n-HEA. Notably, the typical Co sites exhibit the lowest energy barrier for NRA with *NH2 to *NH3as the rate-determining step.

16.
Angew Chem Int Ed Engl ; : e202412830, 2024 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-39157915

RESUMEN

In the electrochemical nitrogen reduction reaction (NRR), a leverage relationship exists between NH3-producing activity and selectivity because of the competing hydrogen evolution reaction (HER), which means that high activity with strong protons adsorption causes low product selectivity. Herein, we design a novel metal-organic hydrogen bonding framework (MOHBF) material to modulate this leverage relationship by a hydrogen-bond-regulated proton transfer pathway. The MOHBF material was composited with reduced graphene oxide (rGO) to form a Ni-N2O2 molecular catalyst (Ni-N2O2/rGO). The unique structure of O atoms in Ni-O-C and N-O-H could form hydrogen bonds with H2O molecules to interfere with protons being directly adsorbed onto Ni active sites, thus regulating the proton transfer mechanism and slowing the HER kinetics, thereby modulating the leverage relationship. Moreover, this catalyst has abundant Ni-single-atom sites enriched with Ni-N/O coordination, conducive to the adsorption and activation of N2. The Ni-N2O2/rGO exhibits simultaneously enhanced activity and selectivity of NH3 production with a maximum NH3 yield rate of 209.7 µg h-1 mgcat.-1 and a Faradaic efficiency of 45.7%, outperforming other reported single-atom NRR catalysts.

17.
J Am Chem Soc ; 145(37): 20521-20529, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37672393

RESUMEN

Chalcogens, especially tellurium (Te), as conversion-type cathodes possess promising prospects for zinc batteries (ZBs) with potential rich valence supply and high energy density. However, the conversion reaction of Te is normally restricted to the Te2-/Te0 redox with a low voltage plateau at ∼0.59 V (vs Zn2+/Zn) rather than the expected positive valence conversion of Te0 to Ten+, inhibiting the development of Te-based batteries toward high output voltage and energy density. Herein, the desired reversible Te2-/Te0/Te2+/Te4+ redox behavior with up to six-electron transfer was successfully activated by employing a highly concentrated Cl--containing electrolyte (Cl- as strong nucleophile) for the first time. Three flat discharge plateaus located at 1.24, 0.77, and 0.51 V, respectively, are attained with a total capacity of 802.7 mAh g-1. Furthermore, to improve the stability of Ten+ products and enhance the cycling stability, a modified ionic liquid (IL)-based electrolyte was fabricated, leading to a high-performance Zn∥Te battery with high areal capacity (7.13 mAh cm-2), high energy density (542 Wh kgTe-1 or 227 Wh Lcathdoe+anode-1), excellent cycling performance, and a low self-discharge rate based on 400 mAh-level pouch cell. The results enhance the understanding of tellurium chemistry in batteries, substantially promising a remarkable route for advanced ZBs.

18.
Neurogenetics ; 24(3): 201-208, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37289317

RESUMEN

Unlike the 1p36 microdeletion syndrome, which has been extensively described, 1p36.3 microduplications have rarely been reported. We report the two siblings of familial 1p36.3 microduplication, presenting with a severe global developmental delay, epilepsy, and a few dysmorphic features. They were referred to moderate-to-severe developmental delay (DD) and intellectual disability (ID). Both were considered eyelid myoclonus with absence of epilepsy (Jeavons syndrome). The EEG is characterized by widespread 2.5-3.5 Hz spikes and spike slow complex wave, eye closure sensitivity, and photosensitivity. The children has same dysmorphic features, including mild bitemporal narrowing and sloping forehead, sparse eyebrows, hypertelorism, ptosis, strabismus, infraorbital creases, wide nasal bridge with bulbous nasal tip, dystaxia, hallux valgus, and flat feet. Family exome sequencing revealed a maternally inherited 3.2-Mb microduplication of chromosomal band 1p36.3p36.2. However, DNA purified from blood samples of either parent did not find evidence for a microduplication of 1p36 in somatic tissue, indicating that such a mutation might be carried in the germline of the parents as gonadal mosaicism. No other family members of the affected siblings' parents were reported to be affected by the symptoms found.


Asunto(s)
Epilepsia , Discapacidad Intelectual , Niño , Humanos , Discapacidad Intelectual/genética , Mutación , Epilepsia/genética , Discapacidades del Desarrollo/genética
19.
Anal Chem ; 95(9): 4362-4370, 2023 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-36802515

RESUMEN

In situ synthesis of metal-organic frameworks (MOFs) on flexible materials for the fabrication of functional platforms and micro-devices is challenging. The time-/precursor-consuming procedure and uncontrollable assembly are stumbling blocks for constructing this platform. Herein, a novel in situ MOF synthesis method on paper substrates by use of the ring-oven-assisted technique was reported. Utilizing the ring-oven's heating and washing function, MOFs can be synthesized in 30 min on the designated position of paper chips with extremely low-volume precursors. The principle of this method was explained by steam condensation deposition. The MOFs' growth procedure was theoretically calculated by crystal sizes and the results conformed to the Christian equation. As different MOFs (Cu-MOF-74, Cu-BTB, Cu-BTC) can be synthesized successfully on paper-based chips, the ring-oven-assisted in situ synthesis method has great generality. Then, the prepared Cu-MOF-74 loading paper-based chip was applied to the chemiluminescence (CL) detection of nitrite (NO2-), based on the catalysis effect of Cu-MOF-74 on the NO2--H2O2 CL system. Also, by the delicate design of the paper-based chip, NO2- can be detected with the detection limit (DL) of 0.5 nM in whole blood samples without sample pretreatment. This work establishes a distinctive method for the in situ synthesis of MOFs and the application of MOFs on paper-based CL chips.


Asunto(s)
Estructuras Metalorgánicas , Nitritos , Peróxido de Hidrógeno , Luminiscencia , Dióxido de Nitrógeno
20.
Anal Chem ; 95(2): 1739-1746, 2023 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-36574337

RESUMEN

Volatile formaldehyde (FA) in exhaled breath (EB) is considered as a biomarker for lung cancer (LC). On-the-spot selective and sensitive detection of gaseous FA is rather important for LC screening and diagnosis. Herein, a tetrakis(4-pyridylphenyl)ethylene (Py-TPE)-based zinc metal-organic framework (MOF) with excellent aggregation-induced emission (AIE) property was utilized for absorption and selective detection of FA in EB. The porous Zn-Py-TPE served as a gaseous confinement cavity for the adsorption of FA in EB. Interestingly, Zn-Py-TPE was aggregated on paper, and then aggregation-induced chemiluminescence (CL) emission can be triggered by only adding bis(2,4,6-trichlorophenyl)oxalate (TCPO). Though without H2O2, the CL of Zn-Py-TPE-TCPO was enhanced greatly by FA. FA promoted the aggregation of Zn-Py-TPE on paper by forming halogen bonding between FA and Zn-Py-TPE, which contributed to the better selectivity. FA can also stimulate the production of more singlet oxygen (1O2) in the Zn-Py-TPE-TCPO CL system. Hence, FA could be detected via the proposed Zn-Py-TPE-TCPO system with a quantification linear range of 1.0-100.0 ppb and detection limit of 0.3 ppb. This portable, low-cost, and sensitive paper-based platform can achieve trace FA detection in EB and is expected to provide an on-the-spot screening platform for lung cancer.


Asunto(s)
Neoplasias Pulmonares , Estructuras Metalorgánicas , Humanos , Luminiscencia , Zinc , Peróxido de Hidrógeno , Etilenos , Neoplasias Pulmonares/diagnóstico , Formaldehído
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