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1.
Colloids Surf B Biointerfaces ; 241: 114006, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38870646

RESUMO

Bacterial infections pose a serious threat to human health, and the emergence of superbugs and the growing antibiotic resistance phenomenon have made the development of novel antimicrobial products. In this paper, an ultrasmall Cu, N co-doped carbon dots (CDs-Cu-N) with excellent peroxidase mimic activity and enhanced catalase mimic activity was successfully prepared and anchored to an injectable chitosan (CS)-based hybrid hydrogel. As expected, the CDs-Cu-N-H2O2-CS hybrid hydrogel maintains the excellent enzyme-mimicking properties of CDs-Cu-N and shows superior antibacterial property, which has been proven to effectively promote the healing of S. aureus-infected wounds with good biocompatibility. Benefitting from the dual-enzyme-mimic activity of CDs-Cu-N, the hybrid hydrogel not only can catalyze the generation of highly toxic ROS from low concentration of H2O2 to inhibit the bacterial infections, but also can significantly promote the wound tissue repair and regeneration by improving the anoxic microenvironment and promoting neovascularization. In addition, this hybrid hydrogel also possessed excellent injectability and moldability. It can adapt to various the irregular shapes of acute wounds, maintaining a moist and safe microenvironment while prolonging the action time of nanozyme on wounds, thus promoting wound healing. This injectable hybrid hydrogel shows great potential applications in the field of wound infection management.

2.
Front Public Health ; 12: 1380290, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38818439

RESUMO

Background: Engaging in regular physical activity has been consistently linked to improved physical health and academic performance. Despite its known benefits, there is a concerning trend of decreased physical activity among children globally. The study primarily aims to investigate the level of physical activity among junior high school students in Taiyuan and analyse the main affecting factors from a socio-ecological perspective. Methods: A cross-sectional study was conducted, involving 650 junior high school students from 7 schools in Taiyuan, and 648 valid questionnaires were ultimately collected. The data on students' physical activity levels were collected through the Children's Leisure Activities Study Survey Questionnaire, and the data on factors affecting students' physical activity were collected through the Student Perceived Factors Affecting Physical Activity Questionnaire. Results: In this study, students from the 7th, 8th, and 9th grades participated in physical activities, averaging 214.500 min per week in moderate-intensity and 25.000 min in high-intensity activities, cumulatively averaging 280.000 min weekly. Notably, a significant disparity (p = 0.012) was observed in the combined duration of moderate and high-intensity activities, with male students engaging more time compared to their female counterparts (307.500 vs. 255.000 min). This variance extended across different grades, particularly evident in 8th graders who recorded the highest weekly high-intensity activity duration (31.000 min) and overall physical activity time (320.500 min), surpassing the 7th graders(p = 0.007 for high-intensity activities). Furthermore, an exploratory factor analysis of a 32-item questionnaire, designed to identify determinants of physical activity, revealed six principal components. These components were found to positively correlate with both moderate and high-intensity physical activities. Conclusion: Results emphasize that educational institutions and community programs should collaborate to offer engaging weekend physical activity programs. Schools should develop and implement tailored physical education curricula addressing gender and grade differences. Furthermore, schools and local governments should invest in high-quality sports equipment and facilities.


Assuntos
Exercício Físico , Instituições Acadêmicas , Estudantes , Humanos , Estudos Transversais , Masculino , Feminino , Adolescente , Inquéritos e Questionários , Estudantes/estatística & dados numéricos , China , Criança , Fatores Sexuais
3.
Nat Commun ; 14(1): 8146, 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38065975

RESUMO

The broad employment of clean hydrogen through water electrolysis is restricted by large voltage requirement and energy consumption because of the sluggish anodic oxygen evolution reaction. Here we demonstrate a novel alternative oxidation reaction of green electrosynthesis of valuable 3,3'-diamino-4,4'-azofurazan energetic materials and coupled with hydrogen production. Such a strategy could greatly decrease the hazard from the traditional synthetic condition of 3,3'-diamino-4,4'-azofurazan and achieve low-cell-voltage hydrogen production on WS2/Pt single-atom/nanoparticle catalyst. The assembled two-electrode electrolyzer could reach 10 and 100 mA cm-2 with ultralow cell voltages of 1.26 and 1.55 V and electricity consumption of only 3.01 and 3.70 kWh per m3 of H2 in contrast of the conventional water electrolysis (~5 kWh per m3). Density functional theory calculations combine with experimental design decipher the synergistic effect in WS2/Pt for promoting Volmer-Tafel kinetic rate during alkaline hydrogen evolution reaction, while the oxidative-coupling of starting materials driven by free radical could be the underlying mechanism during the synthesis of 3,3'-diamino-4,4'-azofurazan. This work provides a promising avenue for the concurrent electrosynthesis of energetic materials and low-energy-consumption hydrogen production.

4.
Sensors (Basel) ; 23(20)2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37896741

RESUMO

GPS-based maneuvering target localization and tracking is a crucial aspect of autonomous driving and is widely used in navigation, transportation, autonomous vehicles, and other fields.The classical tracking approach employs a Kalman filter with precise system parameters to estimate the state. However, it is difficult to model their uncertainty because of the complex motion of maneuvering targets and the unknown sensor characteristics. Furthermore, GPS data often involve unknown color noise, making it challenging to obtain accurate system parameters, which can degrade the performance of the classical methods. To address these issues, we present a state estimation method based on the Kalman filter that does not require predefined parameters but instead uses attention learning. We use a transformer encoder with a long short-term memory (LSTM) network to extract dynamic characteristics, and estimate the system model parameters online using the expectation maximization (EM) algorithm, based on the output of the attention learning module. Finally, the Kalman filter computes the dynamic state estimates using the parameters of the learned system, dynamics, and measurement characteristics. Based on GPS simulation data and the Geolife Beijing vehicle GPS trajectory dataset, the experimental results demonstrated that our method outperformed classical and pure model-free network estimation approaches in estimation accuracy, providing an effective solution for practical maneuvering-target tracking applications.

5.
BMC Musculoskelet Disord ; 24(1): 360, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37158913

RESUMO

BACKGROUND: More than 2 million anterior cruciate ligament (ACL) injuries occur worldwide each year. Most surgeons suggest that athletes and active persons with significant knee functional demands, including cutting motions, require and should be offered ligament reconstruction surgery. Despite concentrated rehabilitation efforts, deficits in quadriceps size and strength can persist for years after surgery. Blood flow restriction (BFR) training can help overcome disuse muscular atrophy in the mid-term postoperative period after anterior cruciate ligament reconstruction (ACLR) surgery. The purpose of this study was to evaluate the effects of quadriceps training with different levels of blood flow restriction on quadriceps strength and thickness of participants after ACLR. METHODS: In this study, 30 post-ACL reconstruction participants were randomly divided into three groups (control, 40% Arterial Occlusion Pressure [AOP] and 80% AOP groups). All patients were subjected to different levels of BFR, combined with conventional quadriceps rehabilitation, for 8 weeks. Assessments included scaled maximal isokinetic knee extension strength at 60°/s and 180°/s, the sum of the thickness of the affected femoris rectus and vastus intermedius, Y-balance test performance, and International Knee Documentation Committee questionnaire responses before and after the intervention. RESULTS: In total, 23 participants completed the entire study. The 80% AOP compression group showed an increase in quadriceps femoris muscle strength and muscle thickness (p < 0.01). As compared with the control group, outcome indicators in the 40% AOP and 80% AOP group were improved (p < 0.05). After 8 weeks of experimental BFR intervention, the results were better for the 80% AOP compression group than for the 40% AOP compression group in quadriceps peak torque to body weight at 60°/s and 180°/s angular velocity, as well as the sum of the thickness of the rectus femoris and vastus intermedius. CONCLUSION: The combination of BFR and low-intensity quadriceps femoris training can effectively improve the muscle strength and thickness of knee extensors in participants with ACLR and help reduce the difference between the healthy and surgical sides of the knee joint while improving knee-joint function. Choosing quadriceps training with 80% AOP compression intensity could provide the most benefits. Meanwhile, BFR can accelerate the rehabilitation process of patients and allow early entry into the next rehabilitation cycle. REGISTRATION: Trial registration Chinese Clinical Trial Registry, registration number ChiCTR2100050011, date of registration: 15/08/2021.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Humanos , Músculo Quadríceps/diagnóstico por imagem , Projetos Piloto , Projetos de Pesquisa , Articulação do Joelho , Lesões do Ligamento Cruzado Anterior/cirurgia
6.
BMC Med Genomics ; 16(1): 56, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918839

RESUMO

BACKGROUND: Alzheimer's disease (AD) is a progressive, neurodegenerative disorder with insidious onset. Some scholars believe that there is a close relationship between pyroptosis and AD. However, studies with evidence supporting this relationship are lacking. MATERIALS AND METHODS: The microarray data of AD were retrieved from the Gene Expression Omnibus (GEO) database with the datasets merged using the R package inSilicoMerging. R software package Limma was used to perform the differential expression analysis to identify the differentially expressed genes (DEGs). We further performed the enrichment analyses of the DEGs based on Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases to identify the metabolic pathways with a significant difference. The Gene Set Enrichment Analysis (GSEA) was applied to identify the significant pathways. The protein-protein interaction (PPI) network was constructed based on the STRING database with the hub genes identified. Quantitative real-time PCR (qRT-PCR) analyses based on HT22 cells were performed to validate the findings based on the microarray analysis. Gene expression correlation heatmaps were generated to evaluate the relationships among the genes. RESULTS: A new dataset was derived by merging 4 microarray datasets in the hippocampus of AD patients in the GEO database. Differential gene expression analysis yielded a volcano plot of a total of 20 DEGs (14 up-regulated and 6 down-regulated). GO analysis revealed a group of GO terms with a significant difference, e.g., cytoplasmic vesicle membrane, vesicle membrane, and monocyte chemotaxis. KEGG analysis detected the metabolic pathways with a significant difference, e.g., Rheumatoid arthritis and Fluid shear stress and atherosclerosis. The results of the Gene Set Enrichment Analysis of the microarray data showed that gene set ALZHEIMER_DISEASE and the gene set PYROPTOSIS were both up-regulated. PPI network showed that pyroptosis-related genes were divided into two groups. In the Aß-induced HT22 cell model, three genes (i.e., BAX, IL18, and CYCS) were revealed with significant differences. Gene expression correlation heatmaps revealed strong correlations between pyroptotic genes and AD-related genes. CONCLUSION: The pyroptosis-related genes BAX, IL18, and CYCS were significantly different between AD patients and normal controls.


Assuntos
Doença de Alzheimer , Perfilação da Expressão Gênica , Humanos , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Piroptose/genética , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo , Hipocampo/metabolismo , Biologia Computacional/métodos
7.
Entropy (Basel) ; 25(2)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36832613

RESUMO

The environment and development are major issues of general concern. After much suffering from the harm of environmental pollution, human beings began to pay attention to environmental protection and started to carry out pollutant prediction research. A large number of air pollutant predictions have tried to predict pollutants by revealing their evolution patterns, emphasizing the fitting analysis of time series but ignoring the spatial transmission effect of adjacent areas, leading to low prediction accuracy. To solve this problem, we propose a time series prediction network with the self-optimization ability of a spatio-temporal graph neural network (BGGRU) to mine the changing pattern of the time series and the spatial propagation effect. The proposed network includes spatial and temporal modules. The spatial module uses a graph sampling and aggregation network (GraphSAGE) in order to extract the spatial information of the data. The temporal module uses a Bayesian graph gated recurrent unit (BGraphGRU), which applies a graph network to the gated recurrent unit (GRU) so as to fit the data's temporal information. In addition, this study used Bayesian optimization to solve the problem of the model's inaccuracy caused by inappropriate hyperparameters of the model. The high accuracy of the proposed method was verified by the actual PM2.5 data of Beijing, China, which provided an effective method for predicting the PM2.5 concentration.

8.
Artigo em Inglês | MEDLINE | ID: mdl-36834372

RESUMO

Previous studies have demonstrated that the effect of sports participation on student health and academic performance is significant. However, the relationship between sports participation and academic performance in specific subjects (e.g., English) in the Chinese population is not clear, especially in primary schools. Therefore, the present cross-sectional study aimed to investigate the relationship between sports participation and academic performance in Chinese elementary schools. METHODS: All study participants were asked to self-report their sociodemographic factors (e.g., sex, grade, age), independence, and outcomes. Alongside that, a self-reported questionnaire was used to assess participation in sports and academic performance of three core subjects in China's schooling system (Chinese; math; English; from A to F, with A indicating the best academic performance). An ordered logistic regression, with an odds ratio (OR) at 95%CI confidence interval, was performed to examine the association between sports team participation and academic performance. RESULTS: The final analysis included 27,954 children aged 10-14. Children in the fifth and sixth grades accounted for 50.2% and 49.8%. Chinese, math, and English academic performance were positively correlated with participation in sports. Compared with students who never participate in sports, those students who participate in sports 1-3 times a month, 1-2 times a week, and 3 or more times a week, were more likely to achieve better grades. In terms of math, compared with students who never participate in sports, those students who participate in sports 1-3 times a month, 1-2 times a week, and 3 or more times a week, were more likely to achieve better grades. Regarding English, compared with students who never participate in sports, those students who participate in sports 1-3 times a month, 1-2 times a week, and 3 or more times a week, were more likely to achieve better grades. CONCLUSIONS: Consistent with previous studies, the current study confirms the positive effect of sports participation on children's academic performance. For an academic-related outreach, gender-, grade- and area-specific strategies should be considered in future research.


Assuntos
Desempenho Acadêmico , Esportes , Humanos , Criança , Estudos Transversais , População do Leste Asiático , Instituições Acadêmicas
9.
Talanta ; 255: 124236, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36587430

RESUMO

Acid phosphatase (ACP) is a key marker in the diagnosis of many diseases. However, exploiting a simple and sensitive sensor for the real-time quantitative analysis of ACP is still challenging. Herein, we attempted to develop a sensitive colorimetric sensing strategy for the detection of ACP based on light-activated oxidase mimic property of carbon dots (CDs). The synthesized CDs were proved to be capable of intrinsic light-activated oxidase mimic activity, which could generate reactive oxygen species to oxidize chromogenic substrate under ultraviolet light stimulation. Interestingly, this light-activated oxidase mimic behavior would be effectively suppressed by the antioxidant ascorbic acid (AA), a product from the hydrolysis of 2-phospho-L-ascorbic acid trisodium (AAP) mediated by ACP. Based on the above property, a facile and sensitive colorimetric sensing method for ACP was developed. Under the optimal conditions, the linear range for ACP 0.1-5.5 U/L, and the detection limit was 0.056 U/L. Compared with conventional nanozyme based ACP assay systems, the catalytic activity of light-activated nanozyme could be conveniently regulated by switching the light on and off, which made it easier to precisely control the extent of the reaction and ensured the accuracy of the assay. In addition, the proposed sensing system would be readout directly by the naked eye or smartphone-based RGB analysis system, and have been successfully applied to analyze diluted in diluted fetal bovine serum and urine samples spiked with ACP. All these results indicated that this approach holds good promise for future applications in clinical analysis and point-of-care (POC) biosensor platforms.


Assuntos
Fosfatase Ácida , Oxirredutases , Oxirredutases/química , Fosfatase Ácida/análise , Hidrólise , Ácido Ascórbico/química , Antioxidantes , Colorimetria/métodos , Carbono/química , Limite de Detecção
10.
BMC Plant Biol ; 22(1): 586, 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36517747

RESUMO

BACKGROUND: ASR (abscisic acid-, stress-, and ripening-induced) gene family plays a crucial role in responding to abiotic stresses in plants. However, the roles of ASR genes protecting plants against high salt and drought stresses remain unknown in Tamarix hispida. RESULTS: In this study, a salt and drought-induced ASR gene, ThASR3, was isolated from Tamarix hispida. Transgenic Arabidopsis overexpressing ThASR3 exhibited stimulating root growth and increasing fresh weight compared with wild-type (WT) plants under both salt and water deficit stresses. To further analyze the gain- and loss-of-function of ThASR3, the transgenic T. hispida plants overexpressing or RNA interference (RNAi)-silencing ThASR3 were generated using transient transformation. The overexpression of ThASR3 in Tamarix and Arabidopsis plants displayed enhanced reactive oxygen species (ROS) scavenging capability under high salt and osmotic stress conditions, including increasing the activities of antioxidant enzymes and the contents of proline and betaine, and reducing malondialdehyde (MDA) content and electrolyte leakage rates. CONCLUSION: Our results indicate that ThASR3 functions as a positive regulator in Tamarix responses to salt and osmotic stresses and confers multiple abiotic stress tolerances in transgenic plants, which may have an important application value in the genetic improvement of forest tree resistance.


Assuntos
Arabidopsis , Tamaricaceae , Tamaricaceae/genética , Tamaricaceae/metabolismo , Arabidopsis/metabolismo , Pressão Osmótica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Secas , Cloreto de Sódio/farmacologia , Estresse Fisiológico/genética
11.
Front Bioeng Biotechnol ; 10: 956271, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185440

RESUMO

Plant nuclear factor-Y (NF-Y) transcription factors (TFs) are key regulators of growth and stress resistance. However, the role of NF-Y TFs in poplar in response to biotic stress is still unclear. In this study, we cloned 26 PdbNF-Y encoding genes in the hybrid poplar P. davidiana × P. bollena, including 12 PdbNF-YAs, six PdbNF-YBs, and eight PdbNF-YCs. Their physical and chemical parameters, conserved domains, and phylogeny were subsequently analyzed. The protein-protein interaction (PPI) network showed that the three PdbNF-Y subunits may interact with NF-Y proteins belonging to two other subfamilies and other TFs. Tissue expression analysis revealed that PdbNF-Ys exhibited three distinct expression patterns in three tissues. Cis-elements related to stress-responsiveness were found in the promoters of PdbNF-Ys, and most PdbNF-Ys were shown to be differentially expressed under Alternaria alternata and hormone treatments. Compared with the PdbNF-YB and PdbNF-YC subfamilies, more PdbNF-YAs were significantly induced under the two treatments. Moreover, loss- and gain-of-function analyses showed that PdbNF-YA11 plays a positive role in poplar resistance to A. alternata. Additionally, RT‒qPCR analyses showed that overexpression and silencing PdbNF-YA11 altered the transcript levels of JA-related genes, including LOX, AOS, AOC, COI, JAZ, ORCA, and MYC, suggesting that PdbNF-YA11-mediated disease resistance is related to activation of the JA pathway. Our findings will contribute to functional analysis of NF-Y genes in woody plants, especially their roles in response to biotic stress.

12.
BMC Plant Biol ; 22(1): 413, 2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36008749

RESUMO

BACKGROUND: Populus davidiana × P. bollena is a species of poplar from northeastern China that is characterized by cold resistance and fast growth but now suffers from pathogen infections. Leaf blight caused by Alternaria alternata has become a common poplar disease that causes serious economic impacts, but the molecular mechanisms of resistance to A. alternata in P. davidiana × P. bollena are still unclear. RESULTS: In this study, the transcriptomic response of P. davidiana × P. bollena to A. alternata infection was determined via RNA-Seq. Twelve cDNA libraries were generated from RNA isolated from three biological replicates at four time points (0, 2, 3, and 4 d post inoculation), and a total of 5,930 differentially expressed genes (DEGs) were detected (| log2 fold change |≥ 1 and FDR values < 0.05). Functional analysis revealed that the DEGs were mainly enriched for the "plant hormone signal transduction" pathway, followed by the "phenylpropanoid biosynthesis" pathway. In addition, DEGs that encode defense-related proteins and are related to ROS metabolism were also identified. Numerous transcription factors, such as the bHLH, WRKY and MYB families, were also induced by A. alternata infection. Among these DEGs, those related to JA biosynthesis and JA signal transduction were consistently activated. Therefore, the lipoxygenase gene PdbLOX2, which is involved in JA biosynthesis, was selected for functional characterization. Overexpression of PdbLOX2 enhanced the resistance of P. davidiana × P. bollena to A. alternata, whereas silencing this gene enhanced susceptibility to A. alternata infection. CONCLUSIONS: These results provide new insight into the molecular mechanisms of poplar resistance to A. alternata infection and provide candidate genes for breeding resistant cultivars using genetic engineering.


Assuntos
Populus , Alternaria/fisiologia , Melhoramento Vegetal , Populus/genética , Populus/metabolismo , Transcriptoma
13.
J Med Chem ; 65(13): 8897-8913, 2022 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-35786969

RESUMO

Amphotericin B (AMB, 1) is the most powerful antibiotic in treating potentially life-threatening invasive fungal infections (IFIs), though severe toxicity derived from self-aggregation greatly limits its clinical application. Herein, we applied a bisamidation strategy at the C16-COOH and C3'-NH2 to improve the therapeutic properties by suppressing self-aggregation. It was found that basic amino groups at the residue of C16 amide were beneficial to activity, while lipophilic fragments contributed to toxicity reduction. Additionally, N-methyl-amino acetyl and amino acetyl moieties at C3' amide could help keep the fungistatic effectiveness. The modification work culminated in the discovery of 36 (ED50 = 0.21 mg/kg), which exerted a 1.5-fold stronger antifungal efficacy than amphamide, the optimal derivative theretofore, in mice, low self-aggregation propensity, and thus low acute toxicity. With the improvement in therapeutic index and good PK profile, 36 is promising for further development as a second-generation polyene antifungal agent.


Assuntos
Anfotericina B , Antifúngicos , Amidas/toxicidade , Anfotericina B/uso terapêutico , Anfotericina B/toxicidade , Animais , Antifúngicos/toxicidade , Camundongos , Relação Estrutura-Atividade
14.
ACS Appl Bio Mater ; 5(6): 3067-3074, 2022 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-35658068

RESUMO

Mn2+ release is particularly important for biological application of manganese-based nanomaterials. However, the Mn2+ release profiles of the manganese ferrite nanoparticles are under clarification. Here, we synthesized 3, 10, and 18 nm manganese ferrite nanoparticles (MFNPs) as model systems to study the Mn2+ release behavior, size, and pH-dependent kinetics. The Mn2+ release kinetic study showed that the first-order kinetic model was suitable for 3 and 10 nm MFNPs, while the Higuchi model was suitable for 18 nm MFNPs in a neutral PBS buffer (pH 7.4). In an acidic PBS buffer (pH 4.8), the Mn2+ release from all sizes of MFNPs follows first-order kinetics, which is possible due to the reaction between MFNPs and H+. The influence of Mn2+ release was evaluated by comparing the variations of magnetic resonance (MR) relaxation and magnetic properties before and after Mn2+ release of MFNPs. The results showed that the saturation magnetization (Ms), longitudinal relaxivity (r1), and transverse relaxivity (r2) values declined due to Mn2+ release, while the ratio of r2/r1 increased slightly, showing that all sizes of MFNPs exhibited the same MR mode as the synthesized MFNPs. More importantly, the release kinetics were employed to estimate the toxicity of the released Mn2+in vivo. The potential toxicity is acceptable for MFNP administration since the calculated amount of Mn2+ is in the range of safe doses.


Assuntos
Meios de Contraste , Nanopartículas , Meios de Contraste/química , Compostos Férricos , Cinética , Espectroscopia de Ressonância Magnética , Compostos de Manganês , Metais , Nanopartículas/toxicidade
15.
Adv Mater ; 34(32): e2203900, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35724969

RESUMO

Water electrolysis involves two parallel reactions, that is, oxygen evolution (OER) and hydrogen evolution (HER), in which sluggish OER is a significant limiting step that results in high energy consumption. Coupling the thermodynamically favorable electrooxidation of organic alternatives to value-added fine chemicals HER is a promising approach for the simultaneous cost-effective production of value-added chemicals and hydrogen. Here, a new coupling system for the green electrochemical synthesis of organic energetic materials (EMs) plus hydrogen production using single-atom catalysts is introduced. The catalysts are prepared by the facile galvanostatic deposition of ruthenium single atoms on the molybdenum selenide and reveal a low HER overpotential of 38.9 mV at -10 mA cm-2 in an alkaline medium. Importantly, the cell voltage of water electrolysis can be significantly reduced to only 1.35 V at a current of 10 mA cm-2 by coupling water splitting with the electrooxidation of 5-amino-1H-tetrazole to synthesize 5,5'-azotetrazolate energetic material. These materials are traditionally synthesized under harsh conditions involving a strong oxidizing agent, high-temperature conditions, and difficult separation of by-products. This study provides a green and efficient method of synthesizing organic EMs while simultaneously producing hydrogen.

16.
J Mater Chem B ; 10(17): 3311-3319, 2022 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-35380140

RESUMO

In this work, we reported new Fe3C embedded Fe-N-doped carbon nanomaterials (Fe3C@Fe-N-CMs) generated in situ by the facile pyrolysis of Fe-Zn ZIF precursors. The resulting Fe3C@Fe-N-CMs were equipped with several desirable nanozyme features, including multiple efficient intrinsic active sites (i.e. Fe-Nx, Fe3C@C, and C-N moieties), large specific surface area and abundant mesoporous structures. As a result, these Fe3C@Fe-N-CMs displayed exceptional ability to mimic three enzymes: peroxidase, catalase and oxidase, while the Fe3C@Fe-N-CMs pyrolyzed at 800 °C, named CMs-800, showed the best enzyme-like properties. After systematically investigating the catalytic mechanism, we further explored the application of the oxidase-like properties of CMs-800 in the detection of the total antioxidant capacity (TAC) in beverages and tablets. This study not only provided a new approach to construct multifunctional carbon-based nanozymes, but also expanded the application of carbon nanozymes in the field of food quality and safety.


Assuntos
Carbono , Nanoestruturas , Antioxidantes , Carbono/química , Catálise , Nanoestruturas/química , Oxirredutases
17.
Int J Gen Med ; 15: 243-251, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35023962

RESUMO

OBJECTIVE: This study aims to investigate the correlation of platelet parameters and C-reactive protein (CRP) with depression. METHODS: The clinical data of 61 patients with depression and 30 healthy control subjects were collected to compare the platelet parameters, CRP levels, and Hamilton Depression Rating Scale (HAMD) scores of the two groups for correlation analysis. RESULTS: The results revealed that the body mass index (BMI) of patients with depression was lower (P < 0.05) than that of the healthy control subjects, and that this difference was more significant in women than in men. Patients with severe depression showed an increased mean platelet volume (MPV) (P < 0.05). In the patients with depression, MPV was positively correlated (P < 0.05) with HAMD scores for work and interest, gastrointestinal symptoms, hopelessness, the anxiety/somatization factor, and the hopelessness factor. Platelet count (PLT) was negatively correlated (P < 0.05) with HAMD scores for hypochondriasis, and plateletcrit (PCT) was negatively correlated (P < 0.05) with HAMD scores for middle insomnia and hypochondriasis. Platelet distribution width (PDW) was positively correlated (P < 0.05) with HAMD scores for gastrointestinal and systemic symptoms as well as hopelessness. Higher CRP levels (P < 0.05) were found in the patients with depression than in the healthy control subjects. Furthermore, in the patients with depression, CRP levels were positively correlated (P < 0.05) with HAMD scores for guilt and the cognitive impairment factor. CONCLUSION: Classical platelet parameters (PLT, MPV, PCT, PDW) and CRP were shown to be associated with specific depressive symptoms and cognitive impairment factors, including sleep, gastrointestinal symptoms, hypochondriasis, losing interest in work, and despair. These results suggest that both platelet parameters and CRP could be suitable biomarkers for predicting the occurrence and prognosis of depression, thus providing a new target for its treatment.

18.
Nanoscale ; 13(35): 14960-14972, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34533549

RESUMO

Due to the relatively low photo-thermal conversion efficiency and poor tumor targeting capacity, phototheranostic nanoagents encounter some challenges in cancer photothermal therapy. To address this problem, in the current research we developed vacancy-rich MoSe2-x (0 ≤ x ≤ 1) nanoflowers (MNFs) with molecular 2-deoxy-D-glucose (2-DG) as the activity target, which could be used as a novel phototheranostic nanoagent in the photoacoustic imaging guided chemo-photothermal synergistic therapy. This selenium-deficient structure endows MNFs with high photothermal conversion efficiency (41.7%) due to the strong localized surface plasmon resonances. Besides, the surface linked 2-DG molecules and the flower-like morphology in the nanoagents promoted the targeting effect (active and passive), thus facilitating the efficient concentration of the nanoagents within the tumor site. Both in vitro and in vivo anti-tumor experiments have demonstrated the high synergistic efficacy promoted by MNFs and complete tumor eradication with lower administration dosages could be achieved. This rational design of nanoparticles not only provided the paradigm of high therapeutic efficacy of a chemo-photothermal protocol for precise cancer theranostics, but also expanded the scope of nanomedical applications using semiconductor-based nanoplatforms through well-defined designing of their microstructures and physiochemical properties.


Assuntos
Hipertermia Induzida , Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Fototerapia , Terapia Fototérmica , Nanomedicina Teranóstica
19.
ACS Omega ; 6(21): 13915-13925, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34095683

RESUMO

In this work, the effects of droplet size and reaction time on the adsorption-reaction processes between gelatin and α-[3-(2,3-epoxypropoxy) propyl]-ω-butyl-polydimethylsiloxane (PDMS-E) emulsion droplets were studied. Gelatin molecules were only physically adsorbed on the surface of the PDMS-E droplet in the 0-75 min range, which was unrelated to the droplet size (100-1000 nm). For the small-size droplets (<410 nm), the physical adsorption proceeded over 75 min followed by agglomeration. For middle-size droplets (410-680 nm), the physical adsorption finished at 125 min; subsequently, the nucleophilic reaction between the primary amino group and the epoxy group began to happen, and globular-like or core-shell colloidal particles were formed. For large-size droplets (>680 nm), the nucleophilic reaction occurred at 75 min and produced core-shell or multi-layered colloidal particles. In a word, the physical absorption or nucleophilic reaction between gelatin and PDMS-E emulsion droplets could be controlled by controlling the droplet size and reaction time. Furthermore, the soft tissue paper coated with large-size droplets exhibited excellent resistance to water permeability and flame-resistant performance, which were carried out by water resistance and flammability tests.

20.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 46(2): 135-141, 2021 Feb 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-33678649

RESUMO

OBJECTIVES: Silence of SET domain containing lysine methyltransferase 7 (SET7) alleviates myocardial tissue injury caused by ischemia-reperfusion. But the effects of SET7 on angiotensin II (Ang II)-induced myocardial fibroblast proliferation and the collagen synthesis are not clear. The purpose of this study was to explore the effect of SET7 on the proliferation and collagen synthesis of myocardial fibroblasts and its mechanisms. METHODS: Myocardial fibroblasts were isolated and identified by immunofluorescence. Myocardial fibroblasts were randomly divided into 4 groups: a control group (cells were normally cultured), an Ang II group (cells were treated with 100 nmol/L Ang II for 24 h), a siCtrl group (cells were transfected with siRNA control and were then treated with 100 nmol/L Ang II for 24 h), and a siSET7 group (cells were transfected with siRNA SET7 and were then treated with 100 nmol/L Ang II for 24 h). Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assay were used to evaluate cell proliferation. Real-time PCR was used to detect the mRNA levels of SET7, collagen I, collagen III, and α-smooth muscle actin (α-SMA). Western blotting was used to detect the protein expression of SET7, collagen I, collagen III, α-SMA, sonic hedgehog (Shh), ptched1 (Ptch1), and glioma-associated oncogene homolog 1 (Gli1). RESULTS: Fluorescence microscopy showed positive vimentin staining, and myocardial fibroblasts were in good condition. As compared to the control group, the mRNA and protein levels of SET7 in the Ang II group were significantly upregulated; cell proliferation rate and EdU fluorescence intensity in the Ang II group were significantly increased; the mRNA and protein levels of collagen I, collagen III, and α-SMA were significantly upregulated (all P<0.05). As compared to the siCtrl group, the mRNA and protein levels of SET7 in the siSET7 group were significantly downregulated; cell proliferation rate and EdU fluorescence intensity in the siSET7 group were significantly decreased; the mRNA and protein levels of collagen I, collagen III, and α-SMA in the siSET7 group were significantly downregulated (all P<0.05). CONCLUSIONS: Silence of SET7 gene inhibits Ang II-induced proliferation and collagen synthesis of myocardial fibroblasts. Shh signaling pathway may be involved in this process.


Assuntos
Angiotensina II , Proteínas Hedgehog , Angiotensina II/farmacologia , Proliferação de Células , Células Cultivadas , Colágeno/genética , Fibroblastos
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