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1.
J Colloid Interface Sci ; 674: 624-633, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38945029

RESUMO

Exploiting highly efficient, cost-effective and stable electrocatalysts is key to decreasing hydrogen evolution reaction (HER) kinetics energy barrier. Herein, the alkaline HER kinetics energy barrier can greatly reduce by the joint strategies of the cation vacancy and heterostructure engineering, which is seldom explored and remains ambiguous. In this study, an efficient and stable copper foam-supported Cu3P-CoP heterostructure electrocatalyst with cation vacancy defects (defined as Cu3P-CoP-VAl/CF) was designed for HER via the successive coprecipitation, electrodeposition, alkali etching and phosphorization treatments. As anticipated, the as-obtained Cu3P-CoP-VAl/CF electrocatalyst reveals a remarkable catalytic activity for HER with a low overpotential of 205 mV at a current density of 100 mA·cm-2, a high turnover frequency value of 1.05 s-1 at an overpotential of 200 mV and a small apparent activation energy (Ea) of 9 kJ·mol-1, while shows superior long-term stability at large current densities of 100 and 240 mA·cm-2. Systematic experiment and characterization data demonstrate that the formed cation vacancy could optimize the Ea, leading to the decrease of the kinetic barriers of Cu3P-CoP/CF heterostructure, as well as the established heterogeneous interface induced a synergistic effect between biphasic components on boosting the kinetics toward HER. The results of density functional theory disclose that the synergistic effect of Cu3P-CoP heterostructure could decrease the energy barrier and optimize Gibbs free energy of hydrogen adsorption, resulting in the enhancement of intrinsic catalytic activity of Cu3P-CoP-VAl/CF. More significantly, the alkali-cell assembled by Cu3P-CoP-VAl/CF (cathode) and RuO2/CF (anode) behaves outstanding water splitting performance, delivering a current density of 10 mA·cm-2 at a relatively small applied voltage of 1.58 V, along with encouraging long-term durability. In addition, the alkaline Zn-H2O battery with Cu3P-CoP-VAl/CF as the cathode has been fabricated for the simultaneous generation of electricity and hydrogen, which displays a large power density of up to 4.1 mW·cm-2. The work demonstrates that rational strategy for the design of competent electrocatalysts can effectively accelerate the kinetics of HER, which supplies valuable insights for practical applications in overall water splitting.

2.
Molecules ; 29(6)2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38542979

RESUMO

Recently, perovskite (ABO3) nanomaterials have been widely explored as a class of versatile electrocatalysts for oxygen evolution reactions (OER) due to their remarkable compositional flexibility and structural tunability, but their poor electrical conductivity hinders hydrogen evolution reaction (HER) activity and further limits the large-scale application of perovskite oxide in overall water splitting (OWS). In this study, hollow-nanotube-structure LaxCo0.4Fe0.6O3-δ (x = 1.0, 0.9, and 0.8) perovskites with superior HER/OER activity were synthesized on nickel-iron alloy foam (denoted LaxCoFe/NFF) using hydrothermal with a subsequent calcination strategy. Among them, La0.9CoFe/NFF not only exhibited extraordinary HER electrocatalytic performance (160.5 mV@10 mA cm-2 and 241.0 mV@100 mA cm-2) and stability (20 h@10 mA cm-2), but also displayed significant OER electrocatalytic activity (234.7 mV@10 mA cm-2 and 296.1 mV@100 mA cm-2) and durability (20 h@10 mA cm-2), outperforming many recently reported HER/OER perovskite catalysts. The increase in oxygen vacancies caused by the introduction of La deficiency leads to the expansion of the lattice, which greatly accelerates the HER/OER process of La0.9CoFe/NFF. Additionally, the naturally porous skeleton can prevent catalysts from aggregating as well as delay the corrosion and dissolution of catalysts in the electrolyte under high applied potentials. Furthermore, the assembled two-electrode configuration, utilizing La0.9CoFe/NFF (cathode and anode) electrodes, only requires a low cell voltage of 1.573 V at 10 mA cm-2 for robust alkaline OWS, accompanied by remarkable durability over 20 h. This work provides inspiration for the design and preparation of high-performance and stable bifunctional perovskite electrocatalysts for OWS.

4.
Ann Surg Oncol ; 30(13): 8419-8427, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37605084

RESUMO

BACKGROUND: Near-infrared (NIR) fluorescence-guided surgery with indocyanine green (ICG) has been demonstrated to provide high sensitivity in sentinel lymph node biopsy (SLNB) for breast cancer but has several limitations, such as unstable pharmacokinetics, limited fluorescence brightness, and undesired diffusion to neighboring tissues. This paper investigates the use of Voluven® as the solvent for ICG fluorescence-guided SLNB (ICG-SLNB). METHODS: The photophysical properties of ICG in water and Voluven® were evaluated in laboratory experiments and in a mouse model. Nine patients with early breast cancer underwent subareolar injection of diluted ICG (0.25 mg/ml) for ICG-SLNB. Six of the nine patients received ICG dissolved in Voluven® (ICG:Voluven®), while three were administered ICG dissolved in water (ICG:water); a repetitive injection-observation protocol was followed for all patients. The mapping image quality was evaluated. RESULTS: Laboratory experiments and in vivo mouse study showed improved fluorescence and better targeting using Voluven® as the solvent. ICG-SLNB with a repetitive injection-observation protocol was successfully performed in all nine patients. ICG:Voluven® administration had an overall better signal-to-background ratio (SBR) in sequential sentinel lymph nodes. The rates of transportation within the lymphatics were also improved using ICG:Voluven® compared with ICG:water. CONCLUSIONS: From basic research to animal models to in-human trial, our study proposes a repetitive injection-observation technique with ICG:Voluven®, which is characterized by better transportation and more stable mapping quality for ICG-SLNB in breast cancer patients.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Humanos , Animais , Camundongos , Feminino , Verde de Indocianina , Linfonodo Sentinela/patologia , Neoplasias da Mama/cirurgia , Fluorescência , Biópsia de Linfonodo Sentinela/métodos , Solventes , Água , Corantes , Linfonodos/patologia
5.
Nutrients ; 15(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36678238

RESUMO

Drinking alcohol during adolescence has short-term and long-term effects on physical and mental health. At this stage, teenagers are greatly influenced by their schoolmates and friends. We conducted a multicenter cross-sectional study to investigate the association between school environment factors and adolescents' drinking behavior in China. Using multistage stratified cluster sampling, the study investigated 27,762 middle school students from six cities in China. The logistic regression model was used to explore the association between the school environment and adolescent alcohol drinking behaviors after adjusting for confounders, including gender, age, city, location, and smoking status. Compared with students with none of their close friends drinking, students with more than half of their close friends drinking were more likely to drink in a year (OR = 20.148, 95% CI: 17.722−22.905, p < 0.001) and in a month (OR = 13.433, 95% CI: 11.779−15.319, p < 0.001). In addition, classmates' drinking behaviors, friends' persuasion, and attending parties were risk factors for adolescents' drinking behavior, while the propaganda and regulations of banning drinking in school were protective factors. The school environment, especially friends drinking, is associated with students' drinking behavior. It is necessary to mobilize the strength of schools and peers to strengthen the prevention and control of adolescent drinking.


Assuntos
Comportamento do Adolescente , Consumo de Álcool por Menores , Adolescente , Humanos , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Cidades , Estudos Transversais , Fatores de Risco , Comportamento do Adolescente/psicologia
6.
Front Nutr ; 9: 903216, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35774539

RESUMO

Objective: Adolescents' alcohol consumption has lifetime adverse physical and mental health effects. Family environment factors have a significant influence in shaping adolescents' beliefs and habits. We conducted the multicenter cross-sectional study aiming to investigate the association between family environment factors and adolescent drinking behavior in China. Methods: The study investigated 27,762 middle school students from Beijing, Shanghai, Guangzhou, Jinan, Chengdu, and Harbin. A logistic regression model was used to explore the association between family environmental factors and adolescent drinking behavior. Participants were asked to self-report previous experiences of drinking and getting drunk to access their drinking status. Factors of family environment related to alcohol consumption included: parents' educational level, family economic status, family composition, the number of times parents drank alcohol in the past 30 days, and parents' attitudes toward their drinking behavior. The logistic regression model was used to adjust the demographic confounders, including gender, age, city, location, and smoking status, and to explore the association between family environmental factors and adolescent alcohol drinking behaviors. Results: Compared with students whose parents prohibited drinking, students who were approved drinking were more likely to drink in this year (OR = 16.544, 95%CI:15.265-17.929, P < 0.001; Full adjustment: OR = 13.111, 95% CI: 12.031-14.288, P < 0.001), drink in this month (OR = 7.791, 95% CI: 7.077-8.565, P < 0.001; Full adjustment: OR = 6.010, 95% CI: 5.439-6.641, P < 0.001). In addition, Low family economic status, not living with the mother, parents' ambivalent attitudes toward their children's drinking and parental drinking were risk factors for drinking among middle school students. Conclusion: The family environment, especially parents' attitudes, is associated with students' drinking and drunken behavior. Mobilizing the power of parents may play a positive role in the effective prevention and control of adolescent drinking.

7.
Artigo em Inglês | MEDLINE | ID: mdl-34444573

RESUMO

BACKGROUND AND OBJECTIVE: Overweight or obesity, as an independent risk factor for chronic diseases, has been on the rise globally. Adopting a healthy lifestyle is positive to weight control. Mobile-based lifestyle interventions have shown potential benefits in weight loss, but most studies were carried out among non-elderly population, so it is necessary to perform well-designed randomized controlled trials among the elderly with overweight or obesity. The purpose of this study is to assess the effect of mobile-based lifestyle intervention on weight loss among the overweight and obese elderly population in China. METHODS: This is a prospective, open-labeled, three-month, multicenter, randomized controlled trial involving 750 participants from five cities who were randomly assigned to dietary and physical activity interventions group (DPG; mobile phone with the App and bracelet), physical activity interventions group (PG; mobile phone with the App and bracelet) and control group (CG; no interventions and kept their lifestyle as before). The outcomes evaluated were changes in weight, body mass index (BMI), waist circumference (WC), and hip circumference (HC). RESULTS: In total, 642 (85.6%) participants completed the study, 237 (94.8%), 203 (81.2%), and 202 (80.8%) for DPG, PG, and CG respectively. Comparing with PG and CG, the DPG showed a significant decrease in all outcomes after three months, including body weight (-4.1 kg vs. -1.0 kg; -4.1 kg vs. -0.8 kg; p < 0.05), BMI (-1.6 kg/m2 vs. -0.4 kg/m2; -1.6 kg/m2 vs. -0.3 kg/m2; p < 0.05), WC (-2.8 cm vs. -0.1 cm; -2.8 cm vs. -0.5 cm; p < 0.05), and HC (-3.8 cm vs. -1.3 cm; -3.8 cm vs. -1.3 cm; p < 0.05). Similar effects were seen across sex and BMI subgroups. CONCLUSIONS: Mobile-based lifestyle intervention obtained beneficial effect in weight loss among the elderly with overweight or obesity. Nevertheless, further studies are needed to confirm the effectiveness and its sustainability.


Assuntos
Sobrepeso , Redução de Peso , Idoso , Índice de Massa Corporal , Humanos , Estilo de Vida , Obesidade/terapia , Sobrepeso/terapia , Estudos Prospectivos
8.
Comput Struct Biotechnol J ; 19: 3682-3691, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34285771

RESUMO

Mammalian apurinic/apyrimidinic (AP) endonuclease 1 (APE1) has versatile enzymatic functions, including redox, endonuclease, and exonuclease activities. APE1 is thus broadly associated with pathways in DNA repair, cancer cell growth, and drug resistance. Unlike its AP site-specific endonuclease activity in Base excision repair (BER), the 3'-5' exonucleolytic cleavage of APE1 using the same active site exhibits complex substrate selection patterns, which are key to the biological functions. This work aims to integrate molecular structural information and biocatalytic properties to deduce the substrate recognition mechanism of APE1 as an exonuclease and make connection to its diverse functionalities in the cell. In particular, an induced space-filling model emerges in which a bridge-like structure is formed by Arg177 and Met270 (RM bridge) upon substrate binding, causing the active site to adopt a long and narrow product pocket for hosting the leaving group of an AP site or the 3'-end nucleotide. Rather than distinguishing bases as other exonucleases, the hydrophobicity and steric hindrance due to the APE1 product pocket provides selectivity for substrate structures, such as matched or mismatched blunt-ended dsDNA, recessed dsDNA, gapped dsDNA, and nicked dsDNA with 3'-end overhang shorter than 2 nucleotides. These dsDNAs are similar to the native substrates in BER proofreading, BER for trinucleotide repeats (TNR), Nucleotide incision repair (NIR), DNA single-strand breaks (SSB), SSB with damaged bases, and apoptosis. Integration of in vivo studies, in vitro biochemical assays, and structural analysis is thus essential for linking the APE1 exonuclease activity to the specific roles in cellular functions.

9.
Nat Commun ; 12(1): 601, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33504804

RESUMO

The exonuclease activity of Apurinic/apyrimidinic endonuclease 1 (APE1) is responsible for processing matched/mismatched terminus in various DNA repair pathways and for removing nucleoside analogs associated with drug resistance. To fill in the gap of structural basis for exonucleolytic cleavage, we determine the APE1-dsDNA complex structures displaying end-binding. As an exonuclease, APE1 does not show base preference but can distinguish dsDNAs with different structural features. Integration with assaying enzyme activity and binding affinity for a variety of substrates reveals for the first time that both endonucleolytic and exonucleolytic cleavage can be understood by an induced space-filling model. Binding dsDNA induces RM (Arg176 and Met269) bridge that defines a long and narrow product pocket for exquisite machinery of substrate selection. Our study paves the way to comprehend end-processing of dsDNA in the cell and the drug resistance relating to APE1.


Assuntos
DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , DNA/metabolismo , Exonucleases/metabolismo , Animais , Biocatálise , Domínio Catalítico , DNA/química , Dano ao DNA , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/química , Camundongos , Modelos Moleculares , Especificidade por Substrato
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