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1.
J Colloid Interface Sci ; 678(Pt C): 804-818, 2024 Sep 14.
Article in English | MEDLINE | ID: mdl-39312869

ABSTRACT

The development of cost-efficient bifunctional electrocatalysts is significant for overall water splitting. Herein, we report the in situ fabrication of heterogeneous NF/Ni3S2/Cu2S-X (where X refers to Cu2+ concentrations of 50, 75, and 100 mM) on nickel foam (NF) using an electrodeposition-hydrothermal method. The in situ electrodeposited metallic Cu0 layers on the NF conferred higher stability to the resulting bimetallic sulfide of Ni3S2/Cu2S. In alkaline media (1 M KOH), the optimized NF/Ni3S2/Cu2S-75 exhibited ultra-low overpotentials of 108 and 166 mV during the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) at 10 mA·cm-2. For overall water splitting, the catalyst showed a significantly low cell voltage of 1.50 V and long stabilization time (≥150h)at15mA·cm-2. Density functional theory calculations revealed that the formation of Ni3S2/Cu2S heterojunction reduced the Gibbs free energy of hydrogen adsorption (ΔGH*) on the S site, thus facilitating H2 generation. This study serves as a guide for tailoring transition metal-based catalysts with enhanced activity and long-term durability, thereby contributing to highly efficient water electrolysis for large-scale hydrogen production.

2.
Cardiovasc Diabetol ; 23(1): 331, 2024 Sep 09.
Article in English | MEDLINE | ID: mdl-39252021

ABSTRACT

BACKGROUND: Visceral adipose tissue in individuals with obesity is an independent cardiovascular risk indicator. However, it remains unclear whether adipose tissue influences common cardiovascular diseases, such as atherosclerosis, through its secreted exosomes. METHODS: The exosomes secreted by adipose tissue from diet-induced obesity mice were isolated to examine their impact on the progression of atherosclerosis and the associated mechanism. Endothelial apoptosis and the proliferation and migration of vascular smooth muscle cells (VSMCs) within the atherosclerotic plaque were evaluated. Statistical significance was analyzed using GraphPad Prism 9.0 with appropriate statistical tests. RESULTS: We demonstrate that adipose tissue-derived exosomes (AT-EX) exacerbate atherosclerosis progression by promoting endothelial apoptosis, proliferation, and migration of VSMCs within the plaque in vivo. MicroRNA-132/212 (miR-132/212) was detected within AT-EX cargo. Mechanistically, miR-132/212-enriched AT-EX exacerbates palmitate acid-induced endothelial apoptosis via targeting G protein subunit alpha 12 and enhances platelet-derived growth factor type BB-induced VSMC proliferation and migration by targeting phosphatase and tensin homolog in vitro. Importantly, melatonin decreases exosomal miR-132/212 levels, thereby mitigating the pro-atherosclerotic impact of AT-EX. CONCLUSION: These data uncover the pathological mechanism by which adipose tissue-derived exosomes regulate the progression of atherosclerosis and identify miR-132/212 as potential diagnostic and therapeutic targets for atherosclerosis.


Subject(s)
Apoptosis , Atherosclerosis , Cell Movement , Cell Proliferation , Disease Models, Animal , Disease Progression , Exosomes , Mice, Inbred C57BL , MicroRNAs , Muscle, Smooth, Vascular , Myocytes, Smooth Muscle , Plaque, Atherosclerotic , Animals , MicroRNAs/metabolism , MicroRNAs/genetics , Exosomes/metabolism , Exosomes/pathology , Atherosclerosis/metabolism , Atherosclerosis/pathology , Atherosclerosis/genetics , Cell Proliferation/drug effects , Apoptosis/drug effects , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/pathology , Myocytes, Smooth Muscle/drug effects , Cell Movement/drug effects , Muscle, Smooth, Vascular/pathology , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/drug effects , Male , Signal Transduction , Cells, Cultured , Obesity/metabolism , Obesity/pathology , Mice, Knockout, ApoE , Endothelial Cells/metabolism , Endothelial Cells/pathology , Endothelial Cells/drug effects , Aortic Diseases/pathology , Aortic Diseases/metabolism , Aortic Diseases/genetics , Becaplermin/pharmacology , Becaplermin/metabolism , Intra-Abdominal Fat/metabolism , Intra-Abdominal Fat/pathology , Mice , Humans
3.
Adv Mater ; 36(7): e2306756, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37819771

ABSTRACT

A typical Tesla thermomagnetic engine employs a solid magnetic wheel to convert thermal energy into mechanical energy, while thermomagnetic convection in ferrofluid is still challenging to observe because it is a volume convection that occurs in an enclosed space. Using a water-based ferrofluid, a liquid Tesla thermomagnetic engine is demonstrated and reports the observation of thermomagnetic convection on a free surface. Both types of fluid motions are driven by light and observed by simply placing ferrofluid on a cylindrical magnet. The surface thermomagnetic convection on the free surface is made possible by eliminating the Marangoni effect, while the spinning of the liquid wheel is achieved through the solid-like behavior of the ferrofluid under a strong magnetic field. Increasing the magnetic field reveals a transition from simple thermomagnetic convection to a combination of the central spin of the spiky wheel surrounded by thermomagnetic convection in the outer region of the ferrofluid. The coupling between multiple ferrofluid wheels through a fluid bridge is further demonstrated. These demonstrations not only unveil the unique properties of ferrofluid but also provide a new platform for studying complex fluid dynamics and thermomagnetic convection, opening up exciting opportunities for light-controlled fluid actuation and soft robotics.

4.
J Pharm Pharmacol ; 75(12): 1569-1580, 2023 Dec 08.
Article in English | MEDLINE | ID: mdl-37862582

ABSTRACT

OBJECTIVES: This study addresses the bioavailability challenges associated with oral nicotinamide mononucleotide (NMN) administration by introducing an innovative NMN formulation incorporated with hydroxyapatite (NMN-HAP). METHODS: The NMN-HAP was developed using a wet chemical precipitation and physical adsorption method. To assess its superiority over conventional free NMN, we examined NMN, nicotinamide adenine dinucleotide (NAD+), and nicotinamide riboside (NR) levels in mouse plasma and tissues following oral administration of NMN-HAP. KEY FINDINGS: NMN-HAP nanoparticles demonstrated a rod-shaped morphology, with an average size of ~50 nm, along with encapsulation efficiency and drug loading capacity exceeding 40%. In vitro, drug release results indicated that NMN-HAP exhibited significantly lower release compared with free NMN. In vivo studies showed that NMN-HAP extended circulation time, improved bioavailability compared with free NMN, and elevated plasma levels of NMN, NAD+, and NR. Moreover, NMN-HAP administration displayed tissue-specific distribution with a substantial accumulation of NMN, NAD+, and NR in the brain and liver. CONCLUSION: NMN-HAP represents an ideal formulation for enhancing NMN bioavailability, enabling tissue-specific delivery, and ultimately elevating in vivo NAD+ levels. Considering HAP's biocompatible nature and versatile characteristics, we anticipate that this system has significant potential for various future applications.


Subject(s)
NAD , Nicotinamide Mononucleotide , Mice , Animals , NAD/metabolism , Nicotinamide Mononucleotide/metabolism , Biological Availability , Brain/metabolism , Hydroxyapatites
5.
Nat Commun ; 14(1): 1203, 2023 03 02.
Article in English | MEDLINE | ID: mdl-36864061

ABSTRACT

Large numbers of leaves fall on the earth each autumn. The current treatments of dead leaves mainly involve completely destroying the biocomponents, which causes considerable energy consumption and environmental issues. It remains a challenge to convert waste leaves into useful materials without breaking down their biocomponents. Here, we turn red maple dead leaves into an active three-component multifunctional material by exploiting the role of whewellite biomineral for binding lignin and cellulose. Owing to its intense optical absorption spanning the full solar spectrum and the heterogeneous architecture for effective charge separation, films of this material show high performance in solar water evaporation, photocatalytic hydrogen production, and photocatalytic degradation of antibiotics. Furthermore, it also acts as a bioplastic with high mechanical strength, high-temperature tolerance, and biodegradable features. These findings pave the way for the efficient utilization of waste biomass and innovations of advanced materials.


Subject(s)
Cellulose , Lignin , Biopolymers , Anti-Bacterial Agents , Biomass
6.
Adv Sci (Weinh) ; 10(2): e2204424, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36437041

ABSTRACT

Enhancing electron correlation in a weakly interacting topological system has great potential to promote correlated topological states of matter with extraordinary quantum properties. Here, the enhancement of electron correlation in a prototypical topological metal, namely iridium dioxide (IrO2 ), via doping with 3d transition metal vanadium is demonstrated. Single-crystalline vanadium-doped IrO2 nanowires are synthesized through chemical vapor deposition where the nanowire yield and morphology are improved by creating rough surfaces on substrates. Vanadium doping leads to a dramatic decrease in Raman intensity without notable peak broadening, signifying the enhancement of electron correlation. The enhanced electron correlation is further evidenced by transport studies where the electrical resistivity is greatly increased and follows an unusual T $\sqrt T $ dependence on the temperature (T). The lattice thermal conductivity is suppressed by an order of magnitude via doping even at room temperature where phonon-impurity scattering becomes less important. Density functional theory calculations suggest that the remarkable reduction of thermal conductivity arises from the complex phonon dispersion and reduced energy gap between phonon branches, which greatly enhances phase space for phonon-phonon Umklapp scattering. This work demonstrates a unique system combining 3d and 5d transition metals in isostructural materials to enrich the system with various types of interactions.

7.
J Phys Chem Lett ; 14(1): 1-8, 2023 Jan 12.
Article in English | MEDLINE | ID: mdl-36562535

ABSTRACT

Sodium hydride (NaH) was unprecedently embedded inside graphene nanobubbles via the discovered reaction between NaH and CO. With the graphene nanobubble as a nanoreactor for NaH, we directly observed the electron-beam-induced decomposition process of graphene-covered NaH by in situ high-resolution transmission electron microscopy with energy dispersive spectrometry and electron energy loss spectroscopy, revealing its decomposition mechanism. This can provide guidance for the design of hydrogen storage materials.

8.
Imeta ; 2(4): e132, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38868218

ABSTRACT

With the advancement of sequencing technology, cell separation, and whole-genome amplification techniques, single cell technology for genome sequencing is emerging gradually. In comparison to traditional genome sequencing at the multi-cellular level, single-cell sequencing can not only measure the gene expression level more accurately but also can detect a small amount of gene expression or rare noncoding RNA. This technology has garnered increasing interest among researchers engaged in single-cell studies in recent years. Here, we developed a reproducible computational workflow for scRNA-seq data analysis which including tasks like quality control, normalization, data correction, pseudotime analysis, copy number analysis, etc. We illustrate the application of these steps using publicly available datasets and provide practical recommendations for their implementation. This study serves as a comprehensive tutorial for researchers keen on single-cell data analysis, aiding users in constructing and refining their own analysis pipelines.

9.
Article in English | MEDLINE | ID: mdl-36342908

ABSTRACT

Background and Objectives: As a natural analog of cannabidiol (CBD), nonpsychoactive cannabidivarin (CBDV) has therapeutic potential. However, the precise metabolism of CBDV either in vivo or in vitro has not been fully understood. Objective and Experimental Approach: Therefore, mice were intragastrically administered CBDV, and metabolite-rich and potential target organs and tissues were collected and analyzed by ultrahigh-performance liquid chromatography-quadrupole time-of-flight mass spectrometry. The metabolic pathways of CBDV in mice were illustrated more comprehensively for the first time. Results: Twenty-one metabolites were found, all of which, except decarbonylated CBDV, were initially identified. Compared with CBD, the newly identified metabolic pathways were single dehydrogenation, combined decarbonylation and monohydroxylation, and glutathione conjugations of CBDV and its phase I metabolite. Conclusions: According to the very low response in plasma and the extremely high response in intestinal contents 1 h later after the administration, it was assumed that the oral bioavailability of CBDV was as poor as that of CBD, and the major forms to excrete were conjugates of glutathione and glucuronic acid. In contrast to CBDV, decarbonylated CBDV in the keto form and enol form had considerable responses in plasma and preferred to target fatty tissues and organs owing to their higher lipophilicity. Whether these forms can function as genuine active substances in vivo instead of CBDV is worthy of investigation. These results and supposes contribute notable information regarding the pharmacokinetics and pharmacodynamics of CBDV.

10.
Chemosphere ; 309(Pt 1): 136691, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36209848

ABSTRACT

Zinc oxide (ZnO), which is widely applied for ultraviolet-light driven photocatalysis, has no activity in visible-light photocatalytic process due to its large band gap of ∼3.2 eV. Herein, however, we demonstrated the multiple self-promotion effects of tetracycline as band adjuster, photo-sensitizer, and charge transfer promoter for ZnO nanorods, realizing its visible-light photocatalytic degradation with an excellent removal efficiency up to 91.1% within only 2 h. Besides, the influence of complex realistic factors on this unique process was evaluated together with tests with realistic water matrices. Furthermore, the active species and degradation products were identified. Both acute and developmental toxicities were found to be reduced as the degradation proceeds. These results pave the path for the brand-new self-driven visible-light photocatalysis.


Subject(s)
Nanotubes , Zinc Oxide , Catalysis , Tetracycline , Water
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