Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 293
Filter
1.
J Colloid Interface Sci ; 672: 179-199, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38838627

ABSTRACT

Mesenchymal stem cell-derived exosomes (MSC-Exos) have emerged as promising candidates for cell-free therapy in tissue regeneration. However, the native osteogenic and angiogenic capacities of MSC-Exos are often insufficient to repair critical-sized bone defects, and the underlying immune mechanisms remain elusive. Furthermore, achieving sustained delivery and stable activity of MSC-Exos at the defect site is essential for optimal therapeutic outcomes. Here, we extracted exosomes from osteogenically pre-differentiated human bone marrow mesenchymal stem cells (hBMSCs) by ultracentrifugation and encapsulated them in gelatin methacryloyl (GelMA) hydrogel to construct a composite scaffold. The resulting exosome-encapsulated hydrogel exhibited excellent mechanical properties and biocompatibility, facilitating sustained delivery of MSC-Exos. Osteogenic pre-differentiation significantly enhanced the osteogenic and angiogenic properties of MSC-Exos, promoting osteogenic differentiation of hBMSCs and angiogenesis of human umbilical vein endothelial cells (HUVECs). Furthermore, MSC-Exos induced polarization of Raw264.7 cells from a pro-inflammatory phenotype to an anti-inflammatory phenotype under simulated inflammatory conditions, thereby creating an immune microenvironment conducive to osteogenesis. RNA sequencing and bioinformatics analysis revealed that MSC-Exos activate the p53 pathway through targeted delivery of internal microRNAs and regulate macrophage polarization by reducing DNA oxidative damage. Our study highlights the potential of osteogenic exosome-encapsulated composite hydrogels for the development of cell-free scaffolds in bone tissue engineering.

2.
Int J Mol Sci ; 25(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38731970

ABSTRACT

Malaria is a severe disease that presents a significant threat to human health. As resistance to current drugs continues to increase, there is an urgent need for new antimalarial medications. Aminoacyl-tRNA synthetases (aaRSs) represent promising targets for drug development. In this study, we identified Plasmodium falciparum tyrosyl-tRNA synthetase (PfTyrRS) as a potential target for antimalarial drug development through a comparative analysis of the amino acid sequences and three-dimensional structures of human and plasmodium TyrRS, with particular emphasis on differences in key amino acids at the aminoacylation site. A total of 2141 bioactive compounds were screened using a high-throughput thermal shift assay (TSA). Okanin, known as an inhibitor of LPS-induced TLR4 expression, exhibited potent inhibitory activity against PfTyrRS, while showing limited inhibition of human TyrRS. Furthermore, bio-layer interferometry (BLI) confirmed the high affinity of okanin for PfTyrRS. Molecular dynamics (MD) simulations highlighted the stable conformation of okanin within PfTyrRS and its sustained binding to the enzyme. A molecular docking analysis revealed that okanin binds to both the tyrosine and partial ATP binding sites of the enzyme, preventing substrate binding. In addition, the compound inhibited the production of Plasmodium falciparum in the blood stage and had little cytotoxicity. Thus, okanin is a promising lead compound for the treatment of malaria caused by P. falciparum.


Subject(s)
Antimalarials , Molecular Docking Simulation , Molecular Dynamics Simulation , Plasmodium falciparum , Tyrosine-tRNA Ligase , Plasmodium falciparum/drug effects , Plasmodium falciparum/enzymology , Tyrosine-tRNA Ligase/antagonists & inhibitors , Tyrosine-tRNA Ligase/metabolism , Humans , Antimalarials/pharmacology , Antimalarials/chemistry , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Binding Sites , Protein Binding , Animals , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology
3.
Int J Mol Sci ; 25(9)2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38731817

ABSTRACT

MCPH1 has been identified as the causal gene for primary microcephaly type 1, a neurodevelopmental disorder characterized by reduced brain size and delayed growth. As a multifunction protein, MCPH1 has been reported to repress the expression of TERT and interact with transcriptional regulator E2F1. However, it remains unclear whether MCPH1 regulates brain development through its transcriptional regulation function. This study showed that the knockout of Mcph1 in mice leads to delayed growth as early as the embryo stage E11.5. Transcriptome analysis (RNA-seq) revealed that the deletion of Mcph1 resulted in changes in the expression levels of a limited number of genes. Although the expression of some of E2F1 targets, such as Satb2 and Cdkn1c, was affected, the differentially expressed genes (DEGs) were not significantly enriched as E2F1 target genes. Further investigations showed that primary and immortalized Mcph1 knockout mouse embryonic fibroblasts (MEFs) exhibited cell cycle arrest and cellular senescence phenotype. Interestingly, the upregulation of p19ARF was detected in Mcph1 knockout MEFs, and silencing p19Arf restored the cell cycle and growth arrest to wild-type levels. Our findings suggested it is unlikely that MCPH1 regulates neurodevelopment through E2F1-mediated transcriptional regulation, and p19ARF-dependent cell cycle arrest and cellular senescence may contribute to the developmental abnormalities observed in primary microcephaly.


Subject(s)
Cell Cycle Checkpoints , Cellular Senescence , Cyclin-Dependent Kinase Inhibitor p16 , Mice, Knockout , Microcephaly , Animals , Mice , Cellular Senescence/genetics , Microcephaly/genetics , Microcephaly/metabolism , Microcephaly/pathology , Cell Cycle Checkpoints/genetics , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinase Inhibitor p16/metabolism , Cyclin-Dependent Kinase Inhibitor p16/deficiency , E2F1 Transcription Factor/genetics , E2F1 Transcription Factor/metabolism , Fibroblasts/metabolism , Cell Cycle Proteins/genetics , Cell Cycle Proteins/metabolism
4.
Adv Mater ; : e2313089, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748777

ABSTRACT

The rapid and responsive capabilities of soft robots in perceiving, assessing, and reacting to environmental stimuli are highly valuable. However, many existing soft robots, designed to mimic humans and other higher animals, often rely on data centers for the modulation of mechanoelectrical transduction and electromechanical actuation. This reliance significantly increases system complexity and time delays. Herein, drawing inspiration from Venus flytraps, a soft robot employing a power modulation strategy is presented for active stimulus reaction, eliminating the need for a data center. This robot achieves mechanoelectrical transduction through Ni3(2,3,6,7,10,11-hexaiminotriphenylene)2 (Ni3(HITP)2) metal-organic framework (MOF) with an ultralow time delay (256 ns) and electromechanical actuation via graphite. The Joule heating effect in graphite is effectively modulated by Ni3(HITP)2 before and after the presence of pressure, thus enabling the stimulus reaction of soft robots. As demonstrated, three soft robots are created: low-level edge tongue robots, Venus flytrap robots, and high-level nerve-center-controlled dragonfly robots. This power modulation strategy inspires designs of edge soft robots and high-level robots with a human-like effective fusion of conditioned and unconditioned reflexes.

5.
Int J Biol Macromol ; 270(Pt 2): 132468, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38761900

ABSTRACT

The current outbreak of mpox presents a significant threat to the global community. However, the lack of mpox-specific drugs necessitates the identification of additional candidates for clinical trials. In this study, a network medicine framework was used to investigate poxviruses-human interactions to identify potential drugs effective against the mpox virus (MPXV). The results indicated that poxviruses preferentially target hubs on the human interactome, and that these virally-targeted proteins (VTPs) tend to aggregate together within specific modules. Comorbidity analysis revealed that mpox is closely related to immune system diseases. Based on predicted drug-target interactions, 268 drugs were identified using the network proximity approach, among which 23 drugs displaying the least side-effects and significant proximity to MPXV were selected as the final candidates. Lastly, specific drugs were explored based on VTPs, differentially expressed proteins, and intermediate nodes, corresponding to different categories. These findings provide novel insights that can contribute to a deeper understanding of the pathogenesis of MPXV and development of ready-to-use treatment strategies based on drug repurposing.


Subject(s)
Antiviral Agents , Drug Repositioning , Drug Repositioning/methods , Humans , Antiviral Agents/pharmacology , Protein Interaction Maps/drug effects , Viral Proteins , Host-Pathogen Interactions/drug effects , Computational Biology/methods
6.
Heliyon ; 10(9): e30582, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38765178

ABSTRACT

Aim: To comprehensively evaluate the efficacy of Ultrasound-guided technique for peripheral intravenous catheter placement by nurses in their daily practice. Background: Peripheral intravenous catheter insertion is a common clinical procedure in healthcare settings. Ultrasound-guided peripheral intravenous placement has emerged in recent decades and was recognized as particularly useful in some specific patient groups. Methods: Studies that had compared the ultrasound-guided and traditional approaches were eligible for inclusion and further analysis. The primary outcome was the success rate on the first intravenous insertion attempt. The secondary outcomes included the time needed for successful insertion, and the average number of attempts to establish the IV access. We systematically assess all studies using Cochrane Collaboration's Risk of Bias tool and the Newcastle-Ottawa Scale. We calculated the odds ratio and standardized mean difference with 95 % confidence intervals for the outcomes. Data were analyzed and visualized on Review Manager 5.3.4 and Stata 16.0. Results: 23 studies were included (17 randomized controlled trials and six cohort studies) with a population of 2051 patients offered ultrasound-assisted technique and 2479 treated with the conventional approach for comparison. The former approach was associated with a higher success rate on the first attempt in comparison (OR = 2.95, 95 % CI: 1.86, 4.69). This technique also took less time and less acupuncture to patients' skin (SMD = -0.62, 95 % CI: 1.01, -0.23; SMD = -0.55, 95 % CI: 0.92, -0.18). In the sub-group analyses, children were more likely to benefit from ultrasound guided technique. Ultrasound guided technique demonstrated consistent and significant benefits in emergency clinical settings. Hospitals from different geographical locations exhibited similar trends in the three outcomes. Year of publication and study design revealed inconsistent and insignificant outcomes. Conclusions: Ultrasound-guided technique can be a safer, faster, and more effective alternative to the traditional approach for nurses to establish intravenous access across different clinical settings and age groups.

7.
J Clin Ultrasound ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38813840

ABSTRACT

BACKGROUND: Hypertrophic obstructive cardiomyopathy (HOCM) is clinically symptomatic and prone to malignant arrhythmias and sudden cardiac death (SCD). Currently, an effective treatment is surgical resection of the hypertrophic ventricular septum to relieve the left ventricular outflow tract (LVOT) obstruction and mitral insufficiency. Our center performs an innovative, minimally invasive right infra-axillary thoracotomy for transaortic septal myectomy. Minimally invasive procedures rely more on perioperative transesophageal echocardiography (TEE). This study aimed to explore the use of echocardiography during the perioperative period of surgical intervention for HOCM. METHODS: Between August 2021 and April 2022, 27 patients with HOCM underwent cardiac surgery at our hospital. Minimally invasive transaortic septal resection (Morrow myectomy) was performed from the right axilla. The extent of myectomy and need for mitral valve repair were based on perioperative TEE assessment and surgical findings. The demographic parameters and clinical data of patients were recorded. The cardiopulmonary bypass time, aortic cross-clamp, and mechanical ventilation times were calculated. TEE was used to assess ventricular wall thickening and anatomical abnormalities of mitral regurgitation, assist in intravenous catheterization, and assess the postoperative gradients of the LVOT. RESULTS: Among the 27 patients with HOCM who underwent transaortic septal myectomy by minimally invasive right infra-axillary thoracotomy, 16 had LVOT obstruction, 2 had mid-LV obstruction, and 9 had both LVOT and mid-LV involvement. TEE provides information about the fine structure of the LV cavity and the etiology of the obstruction. In all cases, LVOT obstruction and mitral valve systolic anterior motion were resolved postoperatively, and the degree of mitral regurgitation was significantly reduced. CONCLUSION: Perioperative echocardiography provides valuable information regarding the complex etiology of LVOT obstruction during minimally invasive right infra-axillary thoracotomy for transaortic septal myectomy. It helps determine the extent of septal resection and assess the need for concomitant mitral valve repair.

8.
Front Genet ; 15: 1359579, 2024.
Article in English | MEDLINE | ID: mdl-38586585

ABSTRACT

Background: Systemic inflammatory regulators have been associated with preeclampsia (PE) during pregnancy; however, there is inconsistent evidence from animal models and observational results. Methods: Using summary data from genome-wide association studies (GWASs), we performed a bidirectional Mendelian randomization (MR) analysis of two samples of systemic inflammatory regulators (n = 8,186) and PE (n = 267,242) individuals of European ancestry. As our primary analysis, we used the random-effects inverse-variance weighted (IVW) approach. Sensitivity and pleiotropy analyses were conducted using the MR-Egger method, weighted median, MR Pleiotropy RESidual Sum and Outlier (MR-PRESSO), and Cochran's Q test. Results: The results indicate that there is a correlation between a higher circulating level of tumor necrosis factor alpha (TNF-α) and interleukin-9 (IL-9) and an increased risk of PE (odds ratio [OR] = 1.32, 95% confidence interval [CI] = 1.09-1.60, p = 0.004 and OR = 1.28, 95% CI: 1.02-1.62, p = 0.033, respectively). Conversely, lower levels of stem cell growth factor beta (SCGF-ß) (OR = 0.89, 95% CI: 0.80-0.99, p = 0.027) and interleukin-5 (IL-5) (OR = 0.80, 95% CI: 0.65-0.98, p = 0.030) are linked to an increased risk of PE. The macrophage migration inhibitory factor (MIF) is the downstream inflammatory regulator of PE, according to reverse magnetic resonance imaging studies. Conclusion: Our study suggests that SCGF-ß, IL-5, IL-9, and TNF-α causally affect the PE risk, while PE is causally associated with MIF. Further studies are needed to validate these biomarkers in managing PE.

9.
Sci Bull (Beijing) ; 2024 Mar 09.
Article in English | MEDLINE | ID: mdl-38627135

ABSTRACT

The advancement of flexible electronics demands improved components, necessitating heat dissipation membranes (HDMs) to exhibit high thermal conductivity while maintaining structural integrity and performance stability even after extensive deformation. Herein, we have devised a laser-modulated reduction technique for graphene oxide (GO), enabling the fabrication of high-quality, large-scale, low-defect graphene, which yields high-performance HDMs after orderly deposition. The work underscores the crucial role of the laser wavelength and dispersion liquid's coupling intensity in influencing the morphology and properties of graphene. Optimal coupling effect and energy conversion are realized when a laser of 1064 nm wavelength irradiates a triethylene glycol (TEG)/N,N-Dimethylformamide (DMF) dispersion. This unique synergy generates high transient energy, which facilitates the deprotonation process and ensures a swift, comprehensive GO reduction. In contrast to conventional water-based laser reduction methods, the accelerated reaction magnifies the size of the graphene sheets by mitigating the ablation effect. After membrane construction with an ordered structure, the corresponding membrane exhibits a high thermal conductivity of 1632 W m-1 K-1, requiring only ∼1/10 of the total preparation time required by other reported methods. Remarkably, the resulting HDM demonstrates superior resilience against creasing and folding, maintaining excellent smoothness and negligible reduction in thermal conductivity after violent rubbing. The combination of exceptional flexibility and thermal conductivity in HDMs paves the way for long-term practical use in the flexible electronics industry.

10.
Food Funct ; 15(8): 4614-4626, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38590249

ABSTRACT

The role of vitamin D (VD) in non-alcoholic fatty liver disease (NAFLD) remains controversial, possibly due to the differential effects of various forms of VD. In our study, Sod1 gene knockout (SKO) mice were utilized as lean NAFLD models, which were administered 15 000 IU VD3 per kg diet, or intraperitoneally injected with the active VD analog calcipotriol for 12 weeks. We found that VD3 exacerbated hepatic steatosis in SKO mice, with an increase in the levels of Cd36, Fatp2, Dgat2, and CEBPA. However, calcipotriol exerted no significant effect on hepatic steatosis. Calcipotriol inhibited the expression of Il-1a, Il-1b, Il-6, Adgre1, and TNF, with a reduction of NFκB phosphorylation in SKO mice. No effect was observed by either VD3 or calcipotriol on hepatocyte injury and hepatic fibrosis. Co-immunofluorescence stains of CD68, a liver macrophage marker, and VDR showed that calcipotriol reduced CD68 positive cells, and increased the colocalization of VDR with CD68. However, VD3 elevated hepatocyte VDR expression, with no substantial effect on the colocalization of VDR with CD68. Finally, we found that VD3 increased the levels of serum 25(OH)D3 and 24,25(OH)2D3, whereas calcipotriol decreased both. Both VD3 and calcipotriol did not disturb serum calcium and phosphate levels. In summary, our study found that VD3 accentuated hepatic steatosis, while calcipotriol diminished inflammation levels in SKO mice, and the difference might stem from their distinct cellular selectivity in activating VDR. This study provides a reference for the application of VD in the treatment of lean NAFLD.


Subject(s)
Calcitriol , Calcitriol/analogs & derivatives , Cholecalciferol , Mice, Knockout , Non-alcoholic Fatty Liver Disease , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/genetics , Calcitriol/pharmacology , Mice , Cholecalciferol/pharmacology , Male , Superoxide Dismutase-1/genetics , Superoxide Dismutase-1/metabolism , Liver/metabolism , Liver/drug effects , Receptors, Calcitriol/genetics , Receptors, Calcitriol/metabolism , Inflammation/drug therapy , Mice, Inbred C57BL , Humans , Disease Models, Animal
11.
Discov Nano ; 19(1): 66, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38619656

ABSTRACT

Effective treatment of oily wastewater, which is toxic and harmful and causes serious environmental pollution and health risks, has become an important research field. Membrane separation technology has emerged as a key area of investigation in oil-water separation research due to its high separation efficiency, low costs, and user-friendly operation. This review aims to report on the advances in the research of various types of separation membranes around emulsion permeance, separation efficiency, antifouling efficiency, and stimulus responsiveness. Meanwhile, the challenges encountered in oil-water separation membranes are examined, and potential research avenues are identified.

12.
J Phys Act Health ; : 1-9, 2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38684209

ABSTRACT

BACKGROUND: To assess the associations of replacing sedentary behavior with different types of physical activity with mortality among the US adults of varying diabetes statuses. METHODS: This prospective cohort study included 21,637 participants (mean age, 48.5 y) from the National Health and Nutrition Examination Survey 2007-2018. Physical activity including leisure-time moderate-vigorous-intensity activity (MVPA), walking/bicycling, worktime MVPA, and sedentary behavior. We conducted an isotemporal substitution analysis using Cox regression to estimate the associations between replacements and mortality risks. RESULTS: We found significant protective associations between replacing 30 minutes per day sedentary behavior with 3 types of physical activity and all-cause, cardiovascular disease (CVD) mortality risk (except worktime MVPA for CVD mortality) among total participants, with hazard ratio (HR; 95% confidence interval [CI]) ranging from 0.86 (0.77-0.95) to 0.96 (0.94-0.98). Among participants with diagnosed diabetes, replacing sedentary behavior with leisure-time MVPA was associated with a lower all-cause mortality risk (HR 0.81, 95% CI, 0.70-0.94), which was also observed in other subgroups, with HRs (95% CI) ranging from 0.87 (0.80-0.94) to 0.89 (0.81-0.99). Among those with prediabetes/undiagnosed diabetes, replacing sedentary behavior with walking/bicycling was associated with lower CVD mortality risk, and replacement to work-time MVPA was associated with lower all-cause and CVD mortality risk, with HRs (95% CI) ranging from 0.72 (0.63-0.83) to 0.96 (0.92-0.99). CONCLUSIONS: Replacing sedentary behaviors with 30 minutes per day leisure-time MVPA was associated with lower all-cause mortality, regardless of diabetes statuses. Among people with prediabetes/undiagnosed diabetes, walking/bicycling was additionally associated with lower CVD mortality, and worktime MVPA was associated with lower all-cause and CVD mortality.

13.
Proc Natl Acad Sci U S A ; 121(13): e2317192121, 2024 Mar 26.
Article in English | MEDLINE | ID: mdl-38507451

ABSTRACT

Photothermal heating and photocatalytic treatment are two solar-driven water processing approaches by harnessing NIR and UV-vis light, respectively, which can fully utilize solar energy if integrated. However, it remains a challenge to achieve high performance in both approaches when integrated in a material due to uncontrollable heat diffusion. Here, we report a demonstration of heat confinement on photothermal sites and fluid cooling on photocatalysis sites at the nanoscale, within a well-designed heat and fluid confinement nanofiber reactor. Photothermal and photocatalytic nanostructures were alternatively aligned in electrospun nanofibers for on-demand nanofluidic thermal management as well as easy folding into 3D structures with enhanced light utilization and mass transfer. Such a design showed simultaneously high photothermal evaporation rate (2.59 kg m-2 h-1, exceeding the limit rate) and efficient photocatalytic upcycling of microplastics pollutant into valued products. Enabled by controlled photothermal heating, the valued main product (i.e., methyl acetate) can be evaporated out with 100% selectivity by in situ separation.

14.
Nat Mater ; 23(6): 729-730, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38548900
15.
Nanomaterials (Basel) ; 14(5)2024 Feb 21.
Article in English | MEDLINE | ID: mdl-38470730

ABSTRACT

Polydimethylsiloxane (PDMS) has emerged as a promising candidate for the dielectric layer in implantable sensors due to its exceptional biocompatibility, stability, and flexibility. This study introduces an innovative approach to produce graphene-reinforced PDMS (Gr-PDMS), where graphite powders are exfoliated into mono- and few-layer graphene sheets within the polymer solution, concurrently forming cross-linkages with PDMS. This method yields a uniformly distributed graphene within the polymer matrix with improved interfaces between graphene and PDMS, significantly reducing the percolation threshold of graphene dispersed in PDMS from 10% to 5%. As-synthesized Gr-PDMS exhibits improved mechanical and electrical properties, tested for potential use in capacitive pressure sensors. The results demonstrate an impressive pressure sensitivity up to 0.0273 kpa-1, 45 times higher than that of pristine PDMS and 2.5 times higher than the reported literature value. The Gr-PDMS showcases excellent pressure sensing ability and stability, fulfilling the requirements for implantable intracranial pressure (ICP) sensors.

16.
Small ; : e2305764, 2024 Feb 17.
Article in English | MEDLINE | ID: mdl-38368252

ABSTRACT

Photothermal therapy (PTT) is a new treatment modality for tumors. However, the efficient delivery of photothermal agents into tumors remains difficult, especially in hypoxic tumor regions. In this study, an approach to deliver melanin, a natural photothermal agent, into tumors using genetically engineered bacteria for image-guided photothermal and immune therapy is developed. An Escherichia coli MG1655 is transformed with a recombinant plasmid harboring a tyrosinase gene to produce melanin nanoparticles. Melanin-producing genetically engineered bacteria (MG1655-M) are systemically administered to 4T1 tumor-bearing mice. The tumor-targeting properties of MG1655-M in the hypoxic environment integrate the properties of hypoxia targeting, photoacoustic imaging, and photothermal therapeutic agents in an "all-in-one" manner. This eliminates the need for post-modification to achieve image-guided hypoxia-targeted cancer photothermal therapy. Tumor growth is significantly suppressed by irradiating the tumor with an 808 nm laser. Furthermore, strong antitumor immunity is triggered by PTT, thereby producing long-term immune memory effects that effectively inhibit tumor metastasis and recurrence. This work proposes a new photothermal and immune therapy guided by an "all-in-one" melanin-producing genetically engineered bacteria, which can offer broad potential applications in cancer treatment.

17.
Angew Chem Int Ed Engl ; 63(15): e202400621, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38334221

ABSTRACT

Photo-assisted ion batteries utilize light to boost capacity but face cycling instability due to complex charge/ion transfer under illumination. This study identified photo-induced proton transfer (photo-induced PT) as a significant process in photo-(dis)charging of widely-used V2O5-based zinc-ion batteries, contributing to enhanced capacity under illumination but jeopardizing photo-stability. Photo-induced PT occurs at 100 ps after photo-excitation, inducing rapid proton extraction into V2O5 photoelectrode. This process creates a proton-deficient microenvironment on surface, leading to repetitive cathode dissolution and anode corrosion in each cycle. Enabling the intercalated protons from photo-induced PT to be reversibly employed in charge-discharge processes via the anode-alloying strategy achieves high photo-stability for the battery. Consequently, a ~54 % capacity enhancement was achieved in a V2O5-based zinc-ion battery under illumination, with ~90 % capacity retention after 4000 cycles. This extends the photo-stability record by 10 times. This study offers promising advancements in energy storage by addressing instability issues in photo-assisted ion batteries.

18.
Phys Chem Chem Phys ; 26(7): 6396-6409, 2024 Feb 14.
Article in English | MEDLINE | ID: mdl-38315565

ABSTRACT

Two-dimensional (2D) MBenes have enormous potential in energy applications. Vanadium metal, with its versatile and tunable electronic states, can further enhance the electrochemical performance of MBenes. However, most MBenes are composed of a few atomic layers as the metal boron (MB) block, e.g., M2B2, which might lead to instability and poor mechanical response. Herein, we designed and predicted 2D V4B6 associated with different terminations (T = Cl, O, S) using a top-down method and global search for parental V4AB6. Among the A element candidates, the P-glued MAB phase exhibited high stability and easy synthesizability. Moreover, 2D V4B6 was feasibly formed and easily exfoliated owing to its weak V-P bonding. Most of the surface functionalization could improve both the mechanical and electrochemical properties of the V4B6 monolayer. In particular, 2D V4B6S2 exhibited a high potential as an anode material for lithium-ion batteries (LIBs) with high theoretical capacity (297 mA h g-1), low diffusion barrier (0.166 eV), and low open circuit voltage (0.136 V), outperforming a majority of MXenes and transition metal sulfide layers. This work offers a new strategy for designing desirable 2D layers from parental materials, and tuning their properties via composition and surface functionalization, which could shed light on the development of other 2D metal-ion anodes.

19.
Nanoscale ; 16(6): 3043-3052, 2024 Feb 08.
Article in English | MEDLINE | ID: mdl-38235520

ABSTRACT

Due to limited mass loading, high-capacity electrode materials such as transition metal oxides (TMOs) are essential for microscale Li-ion batteries (LIBs) integrated in nano-/micro-electromechanical systems (N/MEMS). Unfortunately, their electrochemical performances are largely plagued by severe mechanical degradation and slow electron transport. Therefore, it is crucial to develop strategies that can improve the structural stability and electronic conductivity of TMO electrodes. In this work, double-carbon (carbon nanotubes and ketjen black) microsphere (DCMS) supported Co3O4 electrodes are fabricated simply through a spray drying and solvothermal method, which are designed to have a mesoporous three-dimensional (3D) hierarchical heterostructure containing well-dispersed Co3O4 nanoparticles within the DCMS framework. An in situ transmission electron microscopy (TEM) study reveals that the DCMS framework can not only provide facile strain accommodation, but also good electronic conductivity, leading to a much improved Li-storage performance compared to other Co3O4-based anodes. The hierarchical electrode exhibits maximum charge capacities of 1205.2 and 678.1 mA h g-1 at current densities of 0.1 and 2 A g-1, respectively, as well as a capacity retention of 92.2% at 0.3 A g-1 after 100 cycles. This study provides a low-cost, simple and general method for developing advanced high-capacity electrodes.

20.
Biomed Opt Express ; 15(1): 59-76, 2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38223179

ABSTRACT

Hypoxia is a critical tumor microenvironment (TME) component. It significantly impacts tumor growth and metastasis and is known to be a major obstacle for cancer therapy. Integrating hypoxia modulation with imaging-based monitoring represents a promising strategy that holds the potential for enhancing tumor theranostics. Herein, a kind of nanoenzyme Prussian blue (PB) is synthesized as a metal-organic framework (MOF) to load the second near-infrared (NIR-II) small molecule dye IR1061, which could catalyze hydrogen peroxide to produce oxygen and provide a photothermal conversion element for photoacoustic imaging (PAI) and photothermal therapy (PTT). To enhance stability and biocompatibility, silica was used as a coating for an integrated nanoplatform (SPI). SPI was found to relieve the hypoxic nature of the TME effectively, thus suppressing tumor cell migration and downregulating the expression of heat shock protein 70 (HSP70), both of which led to an amplified NIR-II PTT effect in vitro and in vivo, guided by the NIR-II PAI. Furthermore, label-free multi-spectral PAI permitted the real-time evaluation of SPI as a putative tumor treatment. A clinical histological analysis confirmed the amplified treatment effect. Hence, SPI combined with PAI could offer a new approach for tumor diagnosing, treating, and monitoring.

SELECTION OF CITATIONS
SEARCH DETAIL
...