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1.
Angew Chem Int Ed Engl ; : e202409719, 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39052469

RESUMO

Stable solid-electrolyte interphase (SEI) is crucial for cycling reversibility of Na-ion batteries by mitigating continuous side reactions. So far, the severe SEI dissolution leads to low Coulombic efficiency (CE) and short cycle life. Meanwhile, the quantified relationship between SEI components and their solubility remains unclear. In this work, we establish the direct correlation between SEI components and SEI solubility, and quantify that the solubility of organic-rich SEI is 3.26 times of inorganic-rich SEI. We further propose a feasible strategy to preform inorganic-rich insoluble SEI and demonstrate a practical hard carbon (HC)||NaMn0.33Fe0.33Ni0.33O2 full cell in commercial electrolyte of 1 M NaPF6 in propylene carbonate (PC) with 80.0% capacity retention for 900 cycles, and achieve a record-high average CE of 99.95% for a practical Na-ion full cell. This study provides an effective strategy of preforming insoluble SEI to suppress its dissolution towards highly reversible Na-ion batteries.

2.
Angew Chem Int Ed Engl ; 63(8): e202317942, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38179820

RESUMO

CO2 electroreduction (CO2 R) operating in acidic media circumvents the problems of carbonate formation and CO2 crossover in neutral/alkaline electrolyzers. Alkali cations have been universally recognized as indispensable components for acidic CO2 R, while they cause the inevitable issue of salt precipitation. It is therefore desirable to realize alkali-cation-free CO2 R in pure acid. However, without alkali cations, stabilizing *CO2 intermediates by catalyst itself at the acidic interface poses as a challenge. Herein, we first demonstrate that a carbon nanotube-supported molecularly dispersed cobalt phthalocyanine (CoPc@CNT) catalyst provides the Co single-atom active site with energetically localized d states to strengthen the adsorbate-surface interactions, which stabilizes *CO2 intermediates at the acidic interface (pH=1). As a result, we realize CO2 conversion to CO in pure acid with a faradaic efficiency of 60 % at pH=2 in flow cell. Furthermore, CO2 is successfully converted in cation exchanged membrane-based electrode assembly with a faradaic efficiency of 73 %. For CoPc@CNT, acidic conditions also promote the intrinsic activity of CO2 R compared to alkaline conditions, since the potential-limiting step, *CO2 to *COOH, is pH-dependent. This work provides a new understanding for the stabilization of reaction intermediates and facilitates the designs of catalysts and devices for acidic CO2 R.

3.
Rev Cardiovasc Med ; 23(5): 168, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-39077589

RESUMO

Background: Early risk stratification of patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI) has relevant implication for individualized management strategies. The CHA 2 DS 2 -VASc and GRACE ACS risk model are well-established risk stratification systems. We aimed to assess their prognostic performance in AF patients with ACS or PCI. Methods: Consecutive patients with AF and ACS or referred for PCI were prospectively recruited and followed up for 3 years. The primary endpoint was major adverse cardiovascular and cerebrovascular events (MACCEs), including cardiovascular mortality, myocardial infarction, ischemic stroke, systemic embolism and ischemia-driven revascularization. Results: Higher CHA 2 DS 2 -VASc (HR [hazard ratio] 1.184, 95% CI 1.091-1.284) and GRACE at discharge score (HR 1.009, 95% CI 1.004-1.014) were independently associated with increased risk of MACCEs. The CHA 2 DS 2 -VASc (c-statistics: 0.677) and GRACE at discharge (c-statistics: 0.699) demonstrated comparable discriminative capacity for MACCEs (p = 0.281) while GRACE at admission provided relatively lower discrimination (c-statistics: 0.629, p vs. CHA 2 DS 2 -VASc = 0.041). For predicting all-cause mortality, three models displayed good discriminative capacity (c-statistics: 0.750 for CHA 2 DS 2 -VASc, 0.775 for GRACE at admission, 0.846 for GRACE at discharge). A significant discrimination improvement of GRACE at discharge compared to CHA 2 DS 2 -VASc was detected (NRI = 45.13%). Conclusions: In the setting of coexistence of AF and ACS or PCI, CHA 2 DS 2 -VASc and GRACE at discharge score were independently associated with an increased risk of MACCEs. The GRACE at discharge performed better in predicting all-cause mortality.

4.
Chem Sci ; 15(32): 12879-12888, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39148782

RESUMO

Antifluorite-type Li5FeO4 (LFO) belongs to a class of promising prelithiation materials for next-generation high-energy lithium-ion batteries. Unfortunately, the incomplete de-lithiation performance and inferior air stability hinder its application. In this work, ultra-high capacity is achieved by selective doping of Zr into the Fe sites (LFO-Zr) of LFO to form a large number of defects. The underlying defect formation mechanism is comprehensively investigated using density functional theory, revealing that such selective site doping not only enlarges the unit cell volume but also induces Li vacancies into the structure, both of which facilitate lithium-ion migration at a high-rate and promote the redox of oxygen anions. As a result, under 0.05 and 1C rates, the capacity of LFO-Zr reaches 805.7 and 624.5 mA h g-1, which are 69.0 and 262.0 mA h g-1 higher than those of LFO, translating to an increase of 9.4% and 73.3%, respectively. In addition, LFO-Zr exhibits excellent electrochemical performance in a humidity of 20%, with a high capacity of 577.6 mA h g-1 maintained. With the LFO-Zr additive, the full cell delivered 193.6 mA h g-1 for the initial cycle at 0.1C. The defect engineering strategy presented in this work delivers insights to promote ultra-high capacity and high-rate performance of air-stable LFO.

5.
Chem Sci ; 15(29): 11188-11228, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39055002

RESUMO

The oxygen reduction reaction (ORR) is a key component for many clean energy technologies and other industrial processes. However, the low selectivity and the sluggish reaction kinetics of ORR catalysts have hampered the energy conversion efficiency and real application of these new technologies mentioned before. Recently, tremendous efforts have been made in mechanism understanding, electrocatalyst development and system design. Here, a comprehensive and critical review is provided to present the recent advances in the field of the electrocatalytic ORR. The two-electron and four-electron transfer catalytic mechanisms and key evaluation parameters of the ORR are discussed first. Then, the up-to-date synthetic strategies and in situ characterization techniques for ORR electrocatalysts are systematically summarized. Lastly, a brief overview of various renewable energy conversion devices and systems involving the ORR, including fuel cells, metal-air batteries, production of hydrogen peroxide and other chemical synthesis processes, along with some challenges and opportunities, is presented.

6.
Biosci Trends ; 18(1): 94-104, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38325821

RESUMO

This study aimed to investigate the causal role of diabetes mellitus (DM), glycemic traits, and sodium-glucose cotransporter 2 (SGLT2) inhibition in pulmonary arterial hypertension (PAH). Utilizing a two-sample two-step Mendelian randomization (MR) approach, we determined the causal influence of DM and glycemic traits (including insulin resistance, glycated hemoglobin, and fasting insulin and glucose) on the risk of PAH. Moreover, we examined the causal effects of SGLT2 inhibition on the risk of PAH. Genetic proxies for SGLT2 inhibition were identified as variants in the SLC5A2 gene that were associated with both levels of gene expression and hemoglobin A1c. Results showed that genetically inferred DM demonstrated a causal correlation with an increased risk of PAH, exhibiting an odds ratio (OR) of 1.432, with a 95% confidence interval (CI) of 1.040-1.973, and a p-value of 0.028. The multivariate MR analysis revealed comparable outcomes after potential confounders (OR = 1.469, 95%CI = 1.021-2.115, p = 0.038). Moreover, genetically predicted SGLT2 inhibition was causally linked to a reduced risk of PAH (OR = 1.681*10-7, 95%CI = 7.059*10-12-0.004, p = 0.002). Therefore, our study identified the suggestively causal effect of DM on the risk of PAH, and SGLT2 inhibition may be a potential therapeutic target in patients with PAH.


Assuntos
Diabetes Mellitus Tipo 2 , Hipertensão Arterial Pulmonar , Humanos , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/complicações , Glicemia , Hipertensão Arterial Pulmonar/complicações , Análise da Randomização Mendeliana , Transportador 2 de Glucose-Sódio/genética , Transportador 2 de Glucose-Sódio/uso terapêutico , Hemoglobinas Glicadas , Polimorfismo de Nucleotídeo Único
7.
ACS Nano ; 18(1): 337-346, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38113246

RESUMO

Layered oxides are widely accepted to be promising cathode candidate materials for K-ion batteries (KIBs) in terms of their rich raw materials and low price, while their further applications are restricted by sluggish kinetics and poor structural stability. Here, the high-entropy design concept is introduced into layered KIB cathodes to address the above issues, and an example of high-entropy layered K0.45Mn0.60Ni0.075Fe0.075Co0.075Ti0.10Cu0.05Mg0.025O2 (HE-KMO) is successfully prepared. Benefiting from the high-entropy oxide with multielement doping, the developed HE-KMO exhibits half-metallic oxide features with a narrow bandgap of 0.19 eV. Increased entropy can also reduce the surface energy of the {010} active facets, resulting in about 2.6 times more exposure of the {010} active facets of HE-KMO than the low-entropy K0.45MnO2 (KMO). Both can effectively improve the kinetics in terms of electron conduction and K+ diffusion. Furthermore, high entropy can inhibit space charge ordering during K+ (de)insertion, and the transition metal-oxygen covalent interaction of HE-KMO is also enhanced, leading to suppressed phase transition of HE-KMO in 1.5-4.2 V and better electrochemical stability of HE-KMO (average capacity drop of 0.20%, 200 cycles) than the low-entropy KMO (average capacity drop of 0.41%, 200 cycles) in the wide voltage window.

8.
Adv Mater ; 36(27): e2403073, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38553938

RESUMO

Na-ion batteries (NIBs) are sustainable alternatives to Li-ion technologies due to the abundant and widely-distributed resources. However, the most promising cathode materials of NIBs so far, O3 layered oxides, suffer from serious air instability issues, which significantly increases the manufactural cost and carbon footprint because of the long-term use of dry rooms. While some feasible strategies are proposed via case studies, universal design strategies for air-stable cathodes are yet to be established. Herein, the air degradation mechanisms of O3 cathodes are investigated via combined first-principles and experimental approaches, with bond dissociation energy proposed as an effective descriptor for predicting air stability. Experimental validations in various unary, binary, and ternary O3 cathodes confirm that the air stability can indeed be effectively improved via simple compositional design. Guided by the predictive model, the designed material can sustain 30-day air-storage without structural or electrochemical degradation. It is calculated that such air-stable cathodes can significantly reduce both energy consumption (≈4 100 000 kWh) and carbon footprint (≈2200-ton CO2) annually for a 2 GWh NIBs manufactory. Therefore, the fundamental understandings and universal design strategy presented open an avenue for rational materials design of NIBs toward both elemental and manufactural sustainability.

9.
Science ; 383(6679): 212-219, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38207038

RESUMO

We expand the concept of epitaxy to a regime of "twisted epitaxy" with the epilayer crystal orientation between two substrates influenced by their relative orientation. We annealed nanometer-thick gold (Au) nanoparticles between two substrates of exfoliated hexagonal molybdenum disulfide (MoS2) with varying orientation of their basal planes with a mutual twist angle ranging from 0° to 60°. Transmission electron microscopy studies show that Au aligns midway between the top and bottom MoS2 when the twist angle of the bilayer is small (<~7°). For larger twist angles, Au has only a small misorientation with the bottom MoS2 that varies approximately sinusoidally with twist angle of the bilayer MoS2. Four-dimensional scanning transmission electron microscopy analysis further reveals a periodic strain variation (<|±0.5%|) in the Au nanodisks associated with the twisted epitaxy, consistent with the Moiré registry of the two MoS2 twisted layers.

10.
Rev Cardiovasc Med ; 25(7): 257, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39139434

RESUMO

Atrial fibrillation (AF) is the most prevalent arrhythmia worldwide. Although the guidelines for AF have been updated in recent years, its gradual onset and associated risk of stroke pose challenges for both patients and cardiologists in real-world practice. Artificial intelligence (AI) is a powerful tool in image analysis, data processing, and for establishing models. It has been widely applied in various medical fields, including AF. In this review, we focus on the progress and knowledge gap regarding the use of AI in AF patients and highlight its potential throughout the entire cycle of AF management, from detection to drug treatment. More evidence is needed to demonstrate its ability to improve prognosis through high-quality randomized controlled trials.

11.
Biomed Pharmacother ; 173: 116406, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460366

RESUMO

Sanguinarine is a quaternary ammonium benzophenanthine alkaloid found in traditional herbs such as Chelidonium, Corydalis, Sanguinarum, and Borovula. It has been proven to possess broad-spectrum biological activities, such as antitumor, anti-inflammatory, antiosteoporosis, neuroprotective, and antipathogenic microorganism activities. In this paper, recent progress on the biological activity and mechanism of action of sanguinarine and its derivatives over the past ten years is reviewed. The results showed that the biological activities of hematarginine and its derivatives are related mainly to the JAK/STAT, PI3K/Akt/mTOR, NF-κB, TGF-ß, MAPK and Wnt/ß-catenin signaling pathways. The limitations of using sanguinarine in clinical application are also discussed, and the research prospects of this subject are outlined. In general, sanguinarine, a natural medicine, has many pharmacological effects, but its toxicity and safety in clinical application still need to be further studied. This review provides useful information for the development of sanguinarine-based bioactive agents.


Assuntos
Alcaloides , Fosfatidilinositol 3-Quinases , Fosfatidilinositol 3-Quinases/metabolismo , Benzofenantridinas/farmacologia , Alcaloides/metabolismo , Isoquinolinas/farmacologia
12.
Heliyon ; 10(15): e35218, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39157410

RESUMO

Background: Restoring and maintaining sinus rhythm in patients with atrial fibrillation (AF) and acute coronary syndrome (ACS) or undergoing percutaneous coronary intervention (PCI) has been studied in clinical trials to reduce symptoms and improve quality of life. Limited data exist on the effectiveness of rate or rhythm control therapy in these patients. Methods: Consecutive patients with AF and ACS or referred for PCI were prospectively recruited in Fuwai Hospital during 2017-2020. The primary endpoints were all-cause death and major adverse cardiovascular and cerebrovascular events (MACCEs), including cardiovascular mortality, myocardial infarction, ischemic stroke, non-central nervous system embolism and ischemia-driven revascularization. Kaplan-Meier curves and Cox regressions were performed to evaluate the association between rhythm/rate control and subsequent outcomes. For the primary endpoints, we used the Benjamini-Hochberg correction for multiple comparisons. Results: A total of 1499 patients with AF and ACS or undergoing PCI were included, with a median follow-up of 34.7 months. Compared to non-rate control, rate control strategy reduced the risk of subsequent MACCEs (adjusted HR, 0.320; 95 % CI 0.220-0.466; p <0.001; *p <0.002) and all-cause death (adjusted HR, 0.148; 95 % CI 0.093-0.236; p <0.001; *p <0.002). Similar trends were observed across all predefined subgroups (p <0.001). In the final multivariate model, rhythm control was not associated with a lower subsequent MACCEs but significantly improved all-cause mortality compared to non-rhythm control (adjusted HR, 0.546; 95 % CI 0.313-0.951; p =0.033; *p =0.044). Conclusions: In this real-world study, rate control strategy was associated with lower risk of MACCEs and all-cause death in AF and ACS or undergoing PCI. Besides, management with rhythm control strategy may improve all-cause mortality.

13.
Theranostics ; 14(9): 3565-3582, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38948069

RESUMO

Cancer therapy has moved from single agents to more mechanism-based targeted approaches. In recent years, the combination of HDAC inhibitors and other anticancer chemicals has produced exciting progress in cancer treatment. Herein, we developed a novel prodrug via the ligation of dichloroacetate to selenium-containing potent HDAC inhibitors. The effect and mechanism of this compound in the treatment of prostate cancer were also studied. Methods: The concerned prodrug SeSA-DCA was designed and synthesized under mild conditions. This compound's preclinical studies, including the pharmacokinetics, cell toxicity, and anti-tumor effect on prostate cancer cell lines, were thoroughly investigated, and its possible synergistic mechanism was also explored and discussed. Results: SeSA-DCA showed good stability in physiological conditions and could be rapidly decomposed into DCA and selenium analog of SAHA (SeSAHA) in the tumor microenvironment. CCK-8 experiments identified that SeSA-DCA could effectively inhibit the proliferation of a variety of tumor cell lines, especially in prostate cancer. In further studies, we found that SeSA-DCA could also inhibit the metastasis of prostate cancer cell lines and promote cell apoptosis. At the animal level, oral administration of SeSA-DCA led to significant tumor regression without obvious toxicity. Moreover, as a bimolecular coupling compound, SeSA-DCA exhibited vastly superior efficacy than the mixture with equimolar SeSAHA and DCA both in vitro and in vivo. Our findings provide an important theoretical basis for clinical prostate cancer treatment. Conclusions: Our in vivo and in vitro results showed that SeSA-DCA is a highly effective anti-tumor compound for PCa. It can effectively induce cell cycle arrest and growth suppression and inhibit the migration and metastasis of PCa cell lines compared with monotherapy. SeSA-DCA's ability to decrease the growth of xenografts is a little better than that of docetaxel without any apparent signs of toxicity. Our findings provide an important theoretical basis for clinical prostate cancer treatment.


Assuntos
Apoptose , Pontos de Checagem do Ciclo Celular , Inibidores de Histona Desacetilases , Neoplasias da Próstata , Fosfatases cdc25 , Masculino , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Humanos , Animais , Apoptose/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , Inibidores de Histona Desacetilases/química , Linhagem Celular Tumoral , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Fosfatases cdc25/metabolismo , Camundongos , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Camundongos Nus , Selênio/farmacologia , Selênio/química , Selênio/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Camundongos Endogâmicos BALB C
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