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1.
Plant Physiol ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38758108

RESUMO

Acidity is a key factor controlling fruit flavor and quality. In a previous study, combined transcriptome and methylation analyses identified a P3A-type ATPase from apple (Malus domestica), MdMa11, which regulates vacuolar pH when expressed in Nicotiana benthamiana leaves. In this study, the role of MdMa11 in controlling fruit acidity was verified in apple calli, fruits, and plantlets. In addition, we isolated an AP2 domain-containing transcription factor, designated MdESE3, based on yeast one-hybrid (Y1H) screening using the MdMa11 promoter as bait. A subcellular localization assay indicated that MdESE3 localized to the nucleus. Analyses of transgenic apple calli, fruits, and plantlets, as well as tomatoes, demonstrated that MdESE3 enhances fruit acidity and organic acid accumulation. Meanwhile, chromatin immunoprecipitation quantitative PCR (ChIP-qPCR), luciferase (LUC) transactivation assays, and GUS reporter assays indicated that MdESE3 could bind to the ethylene-responsive element (ERE; 5'-TTTAAAAT-3') upstream of the MdMa11 transcription start site, thereby activating its expression. Furthermore, MdtDT, MdDTC2, and MdMDH12 expression increased in apple fruits and plantlets overexpressing MdESE3 and decreased in apple fruits and plantlets where MdESE3 was silenced. The ERE was found in MdtDT and MdMDH12 promoters, but not in the MdDTC2 promoter. The Y1H, LUC transactivation assays, and GUS reporter assays indicated that MdESE3 could bind to the MdtDT and MdMDH12 promoters and activate their expression. Our findings provide valuable functional validation of MdESE3 and its role in the transcriptional regulation of MdMa11, MdtDT, and MdMDH12 and malic acid accumulation in apple.

2.
Nano Lett ; 24(20): 6112-6116, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717098

RESUMO

Nanoscale scanning electrochemical probe microscopy started to elucidate the heterogeneity of electrocatalytic activity at electrode surfaces. However, understanding the heterogeneity in product selectivity, another crucial aspect of interfacial reactivity, remains challenging. Herein, we introduce a method combining scanning electrochemical microscopy (SECM) and scanning electrochemical cell microscopy (SECCM) to enable the spatially resolved mapping of both activity and selectivity in electrocatalysis. A dual-channel nanopipette probe was developed: one channel for activity mapping and the other for product detection with a high collection efficiency (>95%) and sensitivity. Simultaneous mapping of activity and selectivity in the oxygen reduction reaction (ORR) is demonstrated. Combined with colocalized crystal orientation mapping, we uncover the local electrocatalytic performance of ORR at different facets on polycrystalline Pt and Au. The high-resolution selectivity mapping enabled by our method with colocalized structural characterization can provide structure-activity-selectivity relationships that are often unavailable in ensemble measurement, holding promise for understanding key structural motifs controlling interfacial reactivity.

3.
Biomater Sci ; 12(10): 2648-2659, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38573023

RESUMO

Titanium (Ti) and its alloys have been widely employed in the treatment of orthopedics and other hard tissue diseases. However, Ti-based implants are bioinert and suffer from bacterial infections and poor osseointegration in clinical applications. Herein, we successfully modified Ti with a porous N-halaminated spermidine-containing polymeric coating (Ti-SPD-Cl) through alkali-heat treatment, surface grafting and chlorination, and it has both excellent antibacterial and osteogenic abilities to significantly enhance osseointegration. The as-obtained Ti-SPD-Cl contains abundant N-Cl groups and demonstrates effective antibacterial ability against S. aureus and E. coli. Meanwhile, due to the presence of the spermidine component and construction of a porous hydrophilic surface, Ti-SPD-Cl is also beneficial for maintaining cell membrane homeostasis and promoting cell adhesion, exhibiting good biocompatibility and osteogenic ability. The rat osteomyelitis model demonstrates that Ti-SPD-Cl can effectively suppress bacterial infection and enhance bone-implant integration. Thus, Ti-SPD-Cl shows promising clinical applicability in the prevention of orthopedic implant infections and poor osseointegration.


Assuntos
Antibacterianos , Materiais Revestidos Biocompatíveis , Escherichia coli , Osseointegração , Ratos Sprague-Dawley , Espermidina , Staphylococcus aureus , Titânio , Titânio/química , Titânio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Osseointegração/efeitos dos fármacos , Animais , Staphylococcus aureus/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Espermidina/farmacologia , Espermidina/química , Escherichia coli/efeitos dos fármacos , Ratos , Polímeros/química , Polímeros/farmacologia , Osteogênese/efeitos dos fármacos , Camundongos , Propriedades de Superfície , Testes de Sensibilidade Microbiana , Masculino
4.
J Am Chem Soc ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607685

RESUMO

Herein, we report the tuning of the activity and selectivity of the oxygen reduction reaction (ORR) through the dynamic regulation of the electrochemical interfaces to surpass the performance of conventional electrocatalysis. This is achieved by applying an oscillating potential between the ORR operating potential and anion adsorbing potential on a gold electrode. Oscillating potential enhances the selectivity for H2O2 by up to 1.35 times compared to the static potential, as confirmed by rotating ring-disk electrode and fluorescence assay measurements. We showed that the enhanced selectivity depends on dynamic adsorption and desorption of anions, and the enhancement occurs in the millisecond time scale or shorter. The transient selectivity to H2O2 can reach ∼97% within the first 5 ms after potential switching. Our results suggest that the dynamic interface can create a transient but unique microenvironment for new reactivity that cannot be reproduced under static conditions, which offers a new dimension in controlling electrocatalysis.

5.
Analyst ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639050

RESUMO

Here, we report a proof-of-concept resistive pulse method for analyzing chiral amino acids utilizing metal-amino acid crystallization differences. This method involves introducing an amino acid sample solution into a micropipette through a pressure-driven flow. The sample then mixes with a metal ion solution inside the pipette, forming metal-amino acid crystals. The crystal size depends on the enantiomeric excess (x) of chiral amino acid samples. Large x values lead to large crystals. The crystal size difference is then reflected in the resistive pulse size as they block the ionic transport in a micropipette to different extents. We used Cd-cystine crystallization as a model system and found approximately five times the mean current pulse size difference for racemic (x = 0) and L-only (x = +1) cystine samples. A similar result was observed for aspartate. Our discovery opens up new opportunities for micro/nanoscopic chiral amino acid analysis, which can potentially be used in single-cell analysis.

6.
J Phys Chem Lett ; 15(16): 4391-4399, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38621259

RESUMO

Water often serves as both a reactant and solvent in electrocatalytic reactions. Interfacial water networks can affect the transport and kinetics of these reactions, e.g., hydrogen evolution reaction and CO2 reduction reaction. Adding cosolvents that influence the hydrogen-bonding (H-bonding) environment, such as dimethyl sulfoxide (DMSO), has the potential to tune the reactivity of these important electrocatalytic reactions by regulating the interfacial local environment and water network. We investigate interfacial H-bonding networks in water-DMSO cosolvent mixtures on gold surfaces by using surface-enhanced infrared absorption spectroscopy and molecular dynamics simulations. Experiments and simulations show that the gold surface is enriched with dehydrated DMSO molecules and the mixture phase-separates to form water clusters. Simulations show a "buckled" water conformation at the surface, further constraining interfacial H-bonding. The small size of these water clusters and the energetically unfavorable H-bond conformations might inhibit H-bonding with bulk water, suppressing the proton diffusion required for efficient hydrogen evolution reaction processes.

7.
Curr Eye Res ; : 1-11, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38482878

RESUMO

PURPOSE: To explore the role of coagulation and fibrinolytic factors, and the potential mechanism of platelet aggregation in the pathogenesis of retinal vein occlusion. METHODS: Coagulation and fibrinolytic parameters in patients with retinal vein occlusion were determined using hemagglutinin and HISCL-5000. Relationships between these elevated parameters and factors representing typical clinical manifestations of retinal vein occlusion were examined, and these parameters were analyzed using a STRING database to indicate the potential role of platelet aggregation. Platelet glycoprotein IIb/IIIa (GPIIb/IIIa) levels were evaluated by flow cytometry after antiplatelet treatment in patients and mouse models. Furthermore, the GPIIb/IIIa ligand fibrinogen in peripheral blood and retina of mouse models was assessed by the turbidimetric method and real-time PCR, respectively. RESULTS: In patients, significant increases in peripheral blood fibrinogen and GPIIb/IIIa levels were observed (p = 0.0040, p < 0.0001, respectively). A positive correlation was observed between macular thickness (MT) and both fibrinogen and GPIIb/IIIa (r = 0.4528, p = 0.0063; r = 0.3789, p = 0.0427, respectively). After intravitreal injections of anti-vascular endothelial growth factor drugs, a significant reduction in fibrinogen levels was observed (p = 0.0072). In addition, the use of antiplatelet drugs resulted in a significant decrease in GPIIb/IIIa (p < 0.0001). In a mouse model, antiplatelet therapy significantly reduced both peripheral blood and retina fibrinogen levels and the overall rate of vein occlusion 3 days after occlusion (p < 0.0005). In addition, the reduction in GPIIb/IIIa levels after antiplatelet therapy was remarkable. CONCLUSION: Fibrinogen and GPIIb/IIIa may be involved in retinal vein occlusion and blocking platelet aggregation may be a new therapeutic approach for retinal vein occlusion.

8.
BMC Geriatr ; 24(1): 258, 2024 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493082

RESUMO

BACKGROUND: Physical activity (PA) plays an important role in the process of several chronic diseases. It may be also associated with the incidence of sarcopenia. This study aimed to determine the association of PA from different components including frequency, duration, intensity, and volume with the incidence of sarcopenia in middle-aged and older adults. METHODS: This study used data from the China Health and Retirement Longitudinal Study in 2011 and 2015. A total of 3,760 individuals aged ≥ 40 years were involved in this study. Sarcopenia was diagnosed using muscle mass, strength and physical performance according to the Asian Working Group for Sarcopenia. PA information including frequency, duration, intensity, and volume was obtained by a self-reported questionnaire. Logistic regression analysis was employed to examine the association between PA and the incidence of sarcopenia at 4-year follow-up. RESULTS: The incidence of sarcopenia was 5.9% during the 4-year follow-up. Compared to sedentary individuals, those taking 1-2 days or more per week, or a minimum of 10 min each time on vigorous-intensity PA (VPA) had a lower incidence of sarcopenia. Adults spending 3 days or more each week, a minimum of 30 min each time, or 150 min or more per week on moderate-intensity PA (MPA) had a lower presence of sarcopenia than sedentary adults. Adults taking 3 days or more per week, at least 30 min each time, or 150 min or more each week on light-intensity PA (LPA) tended to have a lower incidence of sarcopenia than sedentary individuals. Sensitivity analyses confirmed the robustness of the findings after removing persons with hypertension, dyslipidemia, or diabetes. CONCLUSIONS: These findings suggest that the frequency, duration, and volume of VPA or MPA are negatively associated with the presence of sarcopenia. Participation in LPA tends to have a lower incidence of sarcopenia in middle-aged and older adults.


Assuntos
Sarcopenia , Humanos , Pessoa de Meia-Idade , Idoso , Sarcopenia/diagnóstico , Sarcopenia/epidemiologia , Estudos Longitudinais , Incidência , Exercício Físico/fisiologia , China/epidemiologia
9.
Int J Ophthalmol ; 17(1): 25-33, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38239938

RESUMO

AIM: To provide the direct evidence for the crucial role of trimethylamine N-oxide (TMAO) in vascular permeability and endothelial cell dysfunction under diabetic condition. METHODS: The role of TMAO on the in vitro biological effect of human retinal microvascular endothelial cells (HRMEC) under high glucose conditions was tested by a cell counting kit, wound healing, a transwell and a tube formation assay. The inflammation-related gene expression affected by TMAO was tested by real-time polymerase chain reaction (RT-PCR). The expression of the cell junction was measured by Western blotting (WB) and immunofluorescence staining. In addition, two groups of rat models, diabetic and non-diabetic, were fed with normal or 0.1% TMAO for 16wk, and their plasma levels of TMAO, vascular endothelial growth factor (VEGF), interleukin (IL)-6 and tumor necrosis factor (TNF)-α were tested. The vascular permeability of rat retinas was measured using FITC-Dextran, and the expression of zonula occludens (ZO)-1 and claudin-5 in rat retinas was detected by WB or immunofluorescence staining. RESULTS: TMAO administration significantly increased the cell proliferation, migration, and tube formation of primary HRMEC either in normal or high-glucose conditions. RT-PCR showed elevated inflammation-related gene expression of HRMEC under TMAO stimulation, while WB or immunofluorescence staining indicated decreased cell junction ZO-1 and occludin expression after high-glucose and TMAO treatment. Diabetic rats showed higher plasma levels of TMAO as well as retinal vascular leakage, which were even higher in TMAO-feeding diabetic rats. Furthermore, TMAO administration increased the rat plasma levels of VEGF, IL-6 and TNF-α while decreasing the retinal expression levels of ZO-1 and claudin-5. CONCLUSION: TMAO enhances the proliferation, migration, and tube formation of HRMEC, as well as destroys their vascular integrity and tight connection. It also regulates the expression of VEGF, IL-6, and TNF-α.

10.
Proc Natl Acad Sci U S A ; 121(6): e2309096120, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38285934

RESUMO

Invisibility, a fascinating ability of hiding objects within environments, has attracted broad interest for a long time. However, current invisibility technologies are still restricted to stationary environments and narrow band. Here, we experimentally demonstrate a Chimera metasurface for multiterrain invisibility by synthesizing the natural camouflage traits of various poikilotherms. The metasurface achieves chameleon-like broadband in situ tunable microwave reflection mimicry of realistic water surface, shoal, beach/desert, grassland, and frozen ground from 8 to 12 GHz freely via the circuit-topology-transited mode evolution, while remaining optically transparent as an invisible glass frog. Additionally, the mechanic-driven Chimera metasurface without active electrothermal effect, owning a bearded dragon-like thermal acclimation, can decrease the maximum thermal imaging difference to 3.1 °C in tested realistic terrains, which cannot be recognized by human eyes. Our work transitions camouflage technologies from the constrained scenario to ever-changing terrains and constitutes a big advance toward the new-generation reconfigurable electromagnetics with circuit-topology dynamics.

11.
IEEE Trans Cybern ; 54(5): 3065-3078, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37018686

RESUMO

Synthetic aperture radar (SAR) is capable of obtaining the high-resolution 2-D image of the interested target scene, which enables advanced remote sensing and military applications, such as missile terminal guidance. In this article, the terminal trajectory planning for SAR imaging guidance is first investigated. It is found that the guidance performance of an attack platform is determined by the adopted terminal trajectory. Therefore, the aim of the terminal trajectory planning is to generate a set of feasible flight paths to guide the attack platform toward the target and meanwhile obtain the optimized SAR imaging performance for enhanced guidance precision. The trajectory planning is then modeled as a constrained multiobjective optimization problem given a high-dimensional search space, where the trajectory control and SAR imaging performance are comprehensively considered. By utilizing the temporal-order-dependent property of the trajectory planning problem, a chronological iterative search framework (CISF) is proposed. The problem is decomposed into a series of subproblems, where the search space, objective functions, and constraints are reformulated in chronological order. The difficulty of solving the trajectory planning problem is thus significantly alleviated. Then, the search strategy of CISF is devised to solve the subproblems successively. The optimization results of the preceding subproblem can be utilized as the initial input of the subsequent subproblems to enhance the convergence and search performance. Finally, a trajectory planning method is put forward based on CISF. Experimental studies demonstrate the effectiveness and superiority of the proposed CISF compared with the state-of-the-art multiobjective evolutionary methods. The proposed trajectory planning method can generate a set of feasible terminal trajectories with optimized mission performance.

12.
Biomol Biomed ; 24(2): 387-394, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-37838927

RESUMO

Retinal vein occlusion (RVO) ranks as the second most prevalent retinal vascular disease, following diabetic retinopathy. Neutrophil extracellular traps (NETs) play an important role in vascular diseases. This study aimed to elucidate the relationship between NETs and RVO, and to discern the potential role of deoxyribonuclease I (DNase I) in the prevention and treatment of RVO through the modulation of NETs. We analyzed circulating NETs biomarkers, namely cell-free DNA (cf-DNA), myeloperoxidase (MPO)-DNA, and neutrophil elastase (NE), in 30 RVO patients and 30 healthy individuals. We established an RVO mouse model using a retinal laser, and the mice were categorized into two groups: the DNase I group and the control group. Retinal images were taken at predetermined time points, and the state of the retinal vessels was assessed. Both tissue and blood samples were harvested for analysis of NETs expression through methods such as western blotting, immunofluorescence staining, and enzyme-linked immunosorbent assay (ELISA). Our finding indicate an increase in circulating NETs biomarkers in human and mouse RVO cases, while also verifying the presence of NETs in the retinal thrombus of the RVO model. Both in vitro and in vivo tests revealed that DNase I attenuated NETs formation. Moreover, DNase I injections led to diminished NETs biomarker levels and a reduced duration of the thrombus after the RVO model establishment. Consequently, DNase I, a well-established modulator of NETs formation, might exhibit protective properties in the prevention and treatment of RVO.


Assuntos
Armadilhas Extracelulares , Oclusão da Veia Retiniana , Animais , Humanos , Camundongos , Biomarcadores/metabolismo , Desoxirribonuclease I , DNA , Armadilhas Extracelulares/metabolismo , Oclusão da Veia Retiniana/metabolismo
13.
Br J Pharmacol ; 181(6): 896-913, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37309219

RESUMO

BACKGROUND AND PURPOSE: Overexpression of astrocytic lactoferrin (Lf) was observed in the brain of Alzheimer's disease (AD) patients, whereas the role of astrocytic Lf in AD progression remains unexplored. In this study, we aimed to evaluate the effects of astrocytic Lf on AD progression. EXPERIMENTAL APPROACH: Male APP/PS1 mice with astrocytes overexpressing human Lf were developed to evaluate the effects of astrocytic Lf on AD progression. N2a-sw cells also were employed to further uncover the mechanism of astrocytic Lf on ß-amyloid (Aß) production. KEY RESULTS: Astrocytic Lf overexpression increased protein phosphatase 2A (PP2A) activity and reduced amyloid precursor protein (APP) phosphorylation, Aß burden and tau hyperphosphorylation in APP/PS1 mice. Mechanistically, astrocytic Lf overexpression promoted the uptake of astrocytic Lf into neurons in APP/PS1 mice, and conditional medium from astrocytes overexpressing Lf inhibited p-APP (Thr668) expression in N2a-sw cells. Furthermore, recombinant human Lf (hLf) significantly enhanced PP2A activity and inhibited p-APP expression, whereas inhibition of p38 or PP2A activities abrogated the hLf-induced p-APP down-regulation in N2a-sw cells. Additionally, hLf promoted the interaction of p38 and PP2A via p38 activation, thereby enhancing PP2A activity, and low-density lipoprotein receptor-related protein 1 (LRP1) knockdown significantly reversed the hLf-induced p38 activation and p-APP down-regulation. CONCLUSIONS AND IMPLICATIONS: Our data suggested that astrocytic Lf promoted neuronal p38 activation, via targeting to LRP1, subsequently promoting p38 binding to PP2A to enhance PP2A enzyme activity, which finally inhibited Aß production via APP dephosphorylation. In conclusion, promoting astrocytic Lf expression may be a potential strategy against AD. LINKED ARTICLES: This article is part of a themed issue From Alzheimer's Disease to Vascular Dementia: Different Roads Leading to Cognitive Decline. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.6/issuetoc.


Assuntos
Doença de Alzheimer , Precursor de Proteína beta-Amiloide , Humanos , Masculino , Camundongos , Animais , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Camundongos Transgênicos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Proteína Fosfatase 2/metabolismo , Lactoferrina/farmacologia , Astrócitos/metabolismo , Peptídeos beta-Amiloides/metabolismo , Modelos Animais de Doenças , Presenilina-1/metabolismo
14.
Pharmacol Res ; 199: 107039, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123108

RESUMO

Zinc is a crucial trace element in the human body, playing a role in various physiological processes such as oxidative stress, neurotransmission, protein synthesis, and DNA repair. The zinc transporters (ZnTs) family members are responsible for exporting intracellular zinc, while Zrt- and Irt-like proteins (ZIPs) are involved in importing extracellular zinc. These processes are essential for maintaining cellular zinc homeostasis. Imbalances in zinc metabolism have been linked to the development of neurodegenerative diseases. Disruptions in zinc levels can impact the survival and activity of neurons, thereby contributing to the progression of neurodegenerative diseases through mechanisms like cell apoptosis regulation, protein phase separation, ferroptosis, oxidative stress, and neuroinflammation. Therefore, conducting a systematic review of the regulatory network of zinc and investigating the relationship between zinc dysmetabolism and neurodegenerative diseases can enhance our understanding of the pathogenesis of these diseases. Additionally, it may offer new insights and approaches for the treatment of neurodegenerative diseases.


Assuntos
Proteínas de Transporte de Cátions , Doenças Neurodegenerativas , Humanos , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Progressão da Doença , Homeostase , Zinco/metabolismo
15.
BMC Public Health ; 23(1): 2489, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38087259

RESUMO

BACKGROUND: This study aimed to evaluate trends in global, regional, and national burdens of intraocular foreign bodies among children and adolescents (aged 0 - 19 years) between 1990 and 2019 according to age, sex, and socio-demographic index. METHODS: This study obtained data from the Global Burden of Disease Study 2019 and evaluated the number of cases, rates per 100,000 persons, and average annual percentage changes among children and adolescents. The annual percentage changes in the incidence and years lived with disability rates across various age groups were investigated using joinpoint software. RESULTS: For intraocular foreign bodies in children and adolescents, the incidence and year lived with disability rates decreased in all age groups between 1990 and 2019. However, the number of incident cases and years lived with disability increased from 1091.94 [95% uncertainty interval (UI), 610.91-1839.52] and 89,245 (95% UI, 6.65-18.67) in 1990 to 1134.85 (95% UI, 665.01-1867.50) and 92,108 (95% UI, 32,052-192,153) in 2019, respectively. Age was positively correlated with the number of cases, incidence, and years lived with disability rates. However, there were significant decreases in both the incidence and years lived with disability rates among children and adolescents, especially in the 15-18 years age group, males, and most high-income regions. Notably, the incidence and years lived with disability rates were significantly decreased in middle and high-middle socio-demographic index regions but were increased in low and low-middle socio-demographic index regions. CONCLUSIONS: Despite the remarkable progress between 1990 and 2019 in reducing the global burden of intraocular foreign bodies, there has been an increase in the number of cases, with substantial disparity across age groups, sexes, regions, and countries. Our results could inform more effective strategies for reducing the burden among children and adolescents.


Assuntos
Pessoas com Deficiência , Corpos Estranhos , Masculino , Criança , Humanos , Adolescente , Prevalência , Carga Global da Doença , Incidência , Saúde Global , Anos de Vida Ajustados por Qualidade de Vida
16.
Front Optoelectron ; 16(1): 39, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038763

RESUMO

Manganese dioxide (MnO2), as a cathode material for multivalent ion (such as Mg2+ and Al3+) storage, is investigated due to its high initial capacity. However, during multivalent ion insertion/extraction, the crystal structure of MnO2 partially collapses, leading to fast capacity decay in few charge/discharge cycles. Here, through pre-intercalating potassium-ion (K+) into δ-MnO2, we synthesize a potassium ion pre-intercalated MnO2, K0.21MnO2·0.31H2O (KMO), as a reliable cathode material for multivalent ion batteries. The as-prepared KMO exhibits a high reversible capacity of 185 mAh/g at 1 A/g, with considerable rate performance and improved cycling stability in 1 mol/L MgSO4 electrolyte. In addition, we observe that aluminum-ion (Al3+) can also insert into a KMO cathode. This work provides a valid method for modification of manganese-based oxides for aqueous multivalent ion batteries.

17.
Sensors (Basel) ; 23(21)2023 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-37960505

RESUMO

To address the rehabilitation needs of upper limb hemiplegic patients in various stages of recovery, streamline the workload of rehabilitation professionals, and provide data visualization, our research team designed a six-degree-of-freedom upper limb exoskeleton rehabilitation robot inspired by the human upper limb's structure. We also developed an eight-channel synchronized signal acquisition system for capturing surface electromyography (sEMG) signals and elbow joint angle data. Utilizing Solidworks, we modeled the robot with a focus on modularity, and conducted structural and kinematic analyses. To predict the elbow joint angles, we employed a back propagation neural network (BPNN). We introduced three training modes: a PID control, bilateral control, and active control, each tailored to different phases of the rehabilitation process. Our experimental results demonstrated a strong linear regression relationship between the predicted reference values and the actual elbow joint angles, with an R-squared value of 94.41% and an average error of four degrees. Furthermore, these results validated the increased stability of our model and addressed issues related to the size and single-mode limitations of upper limb rehabilitation robots. This work lays the theoretical foundation for future model enhancements and further research in the field of rehabilitation.


Assuntos
Articulação do Cotovelo , Exoesqueleto Energizado , Robótica , Humanos , Robótica/métodos , Extremidade Superior , Eletromiografia/métodos
18.
ACS Nano ; 17(22): 22499-22507, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37926957

RESUMO

Bimetallic nanoparticles often show properties superior to their single-component counterparts. However, the large parameter space, including size, structure, composition, and spatial arrangement, impedes the discovery of the best nanoparticles for a given application. High-throughput methods that can control the composition and spatial arrangement of the nanoparticles are desirable for accelerated materials discovery. Herein, we report a methodology for synthesizing bimetallic alloy nanoparticle arrays with precise control over their composition and spatial arrangement. A dual-channel nanopipet is used, and nanofluidic control in the nanopipet further enables precise tuning of the electrodeposition rate of each element, which determines the final composition of the nanoparticle. The composition control is validated by finite element simulation as well as electrochemical and elemental analyses. The scope of the particles demonstrated includes Cu-Ag, Cu-Pt, Au-Pt, Cu-Pb, and Co-Ni. We further demonstrate surface patterning using Cu-Ag alloys with precise control of the location and composition of each pixel. Additionally, combining the nanoparticle alloy synthesis method with scanning electrochemical cell microscopy (SECCM) allows for fast screening of electrocatalysts. The method is generally applicable for synthesizing metal nanoparticles that can be electrodeposited, which is important toward developing automated synthesis and screening systems for accelerated material discovery in electrocatalysis.

19.
Chemosphere ; 345: 140428, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37858765

RESUMO

Persistent organic pollutant perfluorooctane sulfonate (PFOS) is strongly associated with male reproductive disorders, but the related mechanisms are still not fully understood. In this study, we used in vivo and in vitro models to explore the role of organic anion transporting polypeptide 3a1 (Oatp3a1) on PFOS-induced male reproductive injury. Thirty male C57BL/6 (B6) mice were orally given PFOS (0-10 mg/kg/bw) for 28 days. Body weight, organ index, sperm count, histology, and blood-testis barrier (BTB) integrity were evaluated. Primary Sertoli cells were used to describe the related molecular mechanisms of male reproductive injury caused by PFOS. Our results showed that PFOS induced a decrease in sperm count, morphological damage to testicular Sertoli cells, and disruption of BTB. In the in vitro model, exposure to PFOS significantly increased Oatp3a1 mRNA and protein levels and decreased miR-23a-3p expression in Sertoli cells, accompanied by reduced trans-epithelial electrical resistance (TEER) value. By performing the 14C-PFOS uptake experiment, we showed that 14C-PFOS uptake in HEK293-Oatp3a1 cells was apparently higher than in HEK293-MOCK cells. Meanwhile, treating Sertoli cells with Oatp3a1 siRNA significantly decreased Oatp3a1 expression and rescued PFOS-induced decreases in TEER value. As such, the present study highlights that Oatp3a1 may play an important role in the toxic effect of PFOS on Sertoli cells, advancing our understanding of molecular mechanisms for PFOS-induced male reproductive disorders.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Transportadores de Ânions Orgânicos , Masculino , Humanos , Camundongos , Animais , Células de Sertoli , Células HEK293 , Camundongos Endogâmicos C57BL , Sêmen , Ácidos Alcanossulfônicos/metabolismo , Fluorocarbonos/metabolismo , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos/farmacologia
20.
Aesthetic Plast Surg ; 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37794201

RESUMO

PURPOSE: We aim to compare the efficacy and safety of cell-assisted lipotransfer (CAL) and conventional lipotransfer (CLT) in facial filling. METHODS: The PubMed and Embase databases were searched for relevant publications until February 2023. All studies evaluating the efficacy and safety of cell-assisted and conventional lipotransfer in facial filling were included. We calculated pooled standardized mean difference (SMD) and 95% CIs for continuous outcomes and pooled risk ratio (RR) with 95% CIs for binary outcomes. The Cochrane's Risk of Bias Tool and the Newcastle-Ottawa Scale (NOS) were used to evaluate the quality of studies. RESULTS: A total of 15 studies with 737 patients were included in this analysis. The fat survival rate and patient satisfaction rate were significantly higher in the CAL group compared to the CLT group (SMD: 3.04, 95% CI 2.09-3.99; RR: 1.34, 95% CI 1.08-1.67). However, no significant difference in complication rates (RR: 0.95, 95% CI 0.50-1.81) and a lower secondary operation rate in the CAL group (RR: 0.52, 95% CI 0.03-0.82) were observed. No obvious publication bias was observed in the funnel plot (Egger's P values = 0.084 and 0.403). CONCLUSIONS: Based on the pooled results, we tentatively conclude that CAL may have superior fat survival rate and satisfaction rate compared to CLT in facial filling, without compromising patient safety. However, the majority of the included studies were observational studies with small sample sizes. Future research should focus on investigating the long-term efficacy and safety of these techniques. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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