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1.
Nat Aging ; 4(1): 110-128, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129670

RESUMO

The ovary ages earlier than most other tissues, yet the underlying mechanisms remain elusive. Here a comprehensive analysis of transcriptomic landscapes in different organs in young and middle-aged mice revealed that the ovaries showed earlier expression of age-associated genes, identifying increased NADase CD38 expression and decreased NAD+ levels in the ovary of middle-aged mice. Bulk and single-cell RNA sequencing revealed that CD38 deletion mitigated ovarian aging, preserving fertility and follicle reserve in aged mice by countering age-related gene expression changes and intercellular communication alterations. Mechanistically, the earlier onset of inflammation induced higher expression levels of CD38 and decreased NAD+ levels in the ovary, thereby accelerating ovarian aging. Consistently, pharmacological inhibition of CD38 enhanced fertility in middle-aged mice. Our findings revealed the mechanisms underlying the earlier aging of the ovary relative to other organs, providing a potential therapeutic target for ameliorating age-related female infertility.


Assuntos
ADP-Ribosil Ciclase 1 , Envelhecimento , Glicoproteínas de Membrana , Ovário , Animais , Feminino , Camundongos , Envelhecimento/genética , Envelhecimento/metabolismo , NAD/metabolismo , Folículo Ovariano/metabolismo , Ovário/metabolismo , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , ADP-Ribosil Ciclase 1/genética , ADP-Ribosil Ciclase 1/metabolismo
2.
J Colloid Interface Sci ; 658: 334-342, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38113542

RESUMO

Heteroatom doping and heterojunction formation are effective strategies to enhance electrochemical performance. In this study, we present a novel approach that utilizes an ionic liquid-assisted synthesis method to fabricate a BiOBr-based material, which is subsequently loaded onto Mo2CTx via a selenization treatment to create a BiOBr/Bi2Se3 heterostructure, denoted as NBF-BiOBr/Bi2Se3/Mo2CTx. The incorporation of heteroatoms improves its hydrophilicity and electronegativity, while the formation of heterojunctions adjusts the electronic structure at the interface, resulting in lower OH-/H+ adsorption energy. The specific surface area of NBF-BiOBr/Bi2Se3/Mo2CTx is 193.1 m2/g. In hydrogen evolution reaction (HER) tests, NBF-BiOBr/Bi2Se3/Mo2CTx exhibits exceptional catalytic performance in acidic media, requiring only an overpotential of 109 mV to achieve a current density of 10 mA cm-2. Furthermore, NBF-BiOBr/Bi2Se3/Mo2CTx demonstrates superior electrochemical performance in an asymmetric supercapacitor, with an energy density as high as 55.6 Wh kg-1 at a power density of 749.9 Wh kg-1. This work provides a novel approach for heteroatom doping and heterojunction synthesis, offering promising prospects for further advancements in the field.

3.
Adv Sci (Weinh) ; 10(7): e2206029, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36638258

RESUMO

The rational design of catalysts' spatial structure is vitally important to boost catalytic performance by exposing the active sites and increasing specific surface area. Herein, the heteroatom doping and morphology of CoNi metal-organic frameworks(MOF) are modulated by controlling the volume of ionic liquid used in synthesis and generating CoSe2 -NiSe2 heterojunction structures wrapped by N, P, F tri-doped carbon(NPFC) after a selenisation process. Notably, the unique cubic porous structure of CoSe2 -NiSe2 /NPFC results in a specific surface five times that of the sheet-like hollow structure produced without ionic liquid. Moreover, the charge redistribution during heterojunction formation is verified in detail using synchrotron radiation. Density functional theory calculations reveal that the formation of heterojunctions and doping of heteroatoms successfully lower the ΔGH* and ΔGOH* values. Consequently, CoSe2 -NiSe2 /NPFC exhibits excellent activity for HER in both acidic and alkaline solutions. Meanwhile, CoSe2 -NiSe2 /NPFC as a cathode material exhibits excellent performance in a flexible solid-state supercapacitor, with a superior energy density of 55.7 Wh kg-1 at an extremely high-power density of 15.9 kW kg-1 . This material design provides new ideas for not only using ionic liquids to modulate the morphology of MOFs but also deriving heterojunctions and heteroatom-doped carbon from MOFs.

4.
Biochimie ; 209: 44-51, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36708867

RESUMO

Bone marrow stromal cells (BMSCs) possess the capability to differentiate into osteogenic or adipogenic lineages. With aging, BMSCs suffer from mitochondrial dysfunction and undergo senescence, favoring adipogenesis at the expense of osteoblastogenesis. It leads to decreased bone formation and contributes to senile osteoporosis (SOP). In the current study, RNA-seq analysis unveiled that senescent BMSCs from mice exhibited a significant suppression in the expression of the protein disulfide isomerase PDI-6, an important regulator of mitochondrial unfolded protein response (UPRmt) as well as maintenance of mitochondrial homeostasis. Overexpression of PDI-6 in senescent BMSCs partially rescued mitochondrial function and enhanced osteogenic differentiation. In contrast, osteoblastogenesis of BMSCs remarkably deteriorated under the condition of PDI-6 silencing. Furthermore, melatonin, an endocrine hormone, effectively enhanced PDI-6 expression and repaired injured mitochondria, and the effect of melatonin on PDI-6 expression was melatonin receptor dependent. We further identified that PDI-6 was a downstream effector of Wnt/ß-catenin pathway, as the inhibitor of Wnt3A/TCF signaling, Wnt-C59, inhibited PDI-6 expression. Potential ß-catenin-TCF/LEF binding sites on the promoter of PDI-6 gene were also validated by chromatin immunoprecipitation (ChIP) assay. Thus, our study suggests that PDI-6 is a pharmacological target of melatonin for the intervention of age-related osteoporosis via mitigating mitochondrial dysfunction in senescent BMSCs.


Assuntos
Melatonina , Células-Tronco Mesenquimais , Osteoporose , Camundongos , Animais , Osteogênese , Melatonina/farmacologia , Melatonina/metabolismo , beta Catenina/metabolismo , Células-Tronco Mesenquimais/metabolismo , Diferenciação Celular , Osteoporose/tratamento farmacológico , Osteoporose/metabolismo , Envelhecimento , Resposta a Proteínas não Dobradas , Células da Medula Óssea/metabolismo , Via de Sinalização Wnt , Células Cultivadas
5.
Chemosphere ; 308(Pt 3): 136404, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36165840

RESUMO

Sterilization and disinfection of pollutants and microorganisms have been extensively studied in order to address the problem of environmental contamination, which is a crucial issue for public health and economics. Various form of hazardous materials/pollutants including microorganisms and harmful gases are released into the environment that enter into the human body either through inhalation, adsorption or ingestion. The human death rate rises due to various respiratory ailments, strokes, lung cancer, and heart disorders related with these pollutants. Hence, it is essential to control the environmental pollution by applying economical and effective sterilization and disinfections techniques to save life. In general, numerous forms of traditional physical and chemical sterilization and disinfection treatments, such as dry and moist heat, radiation, filtration, ethylene oxide, ozone, hydrogen peroxide, etc. are known along with advanced techniques. In this review we summarized both advanced and conventional techniques of sterilization and disinfection along with their uses and mode of action. This review gives the knowledge about the advantages, disadvantages of both the methods comparatively. Despite, the effective solution given by the advanced sterilization and disinfection technology, joint technologies of sterilization and disinfection has proven to be more effective innovation to protect the indoor and outdoor environments.


Assuntos
Poluentes Ambientais , Ozônio , Desinfecção/métodos , Óxido de Etileno , Substâncias Perigosas , Humanos , Peróxido de Hidrogênio , Esterilização/métodos
6.
Chemosphere ; 302: 134740, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35489452

RESUMO

The low-temperature SCR of NOx by NH3 is restricted in application since the catalysts is easily poisoned by sulfur and water. The Fe modified Mn-Co-Ce/TiO2/SiO2 catalysts synthesized via impregnation method and sulfating were evaluated for low-temperature NH3-SCR in the presence of SO2 and H2O. The calcination temperature and loading amounts of Mn, Fe, Co and Ce were optimized. Adding of Fe into S-MnCoCe/Ti/Si played an important role in resistance to sulfur and water poisoning. The optimal calcination temperature was 380 °C and the optical mass loading of the catalyst was 10% of Mn, 10% of Fe, 1% of Co and 4% of Ce. The optimal S-MnFeCoCe/Ti/Si catalyst maintained high NOx conversion of 93% at reaction temperature of 160 °C in the presence of 50 ppm SO2 and 10 vol% H2O. The catalytic activity did not continue to fall after two times of repeated used in the temperature range of 100-200 °C, indicating its excellent sulfur and water durability and stability in the presence of SO2 and H2O. The interaction between MnOx and FeOx enhanced sulfur and water durability rather than other bi-metal interactions. Furthermore, the mechanism of Fe improving resistance to SO2 and H2O was discussed.


Assuntos
Titânio , Água , Amônia , Catálise , Oxirredução , Dióxido de Silício , Enxofre , Temperatura
7.
J Mater Chem B ; 10(8): 1226-1235, 2022 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-35112697

RESUMO

Ti3C2Tx MXene is a new type of two-dimensional material with good biocompatibility and a good photothermal effect, and shows great potential in cancer treatment. In this study, few-layer ionic liquid (IL)-Ti3C2Tx MXene nanosheets were synthesized using IL stripping technology, which have high chemical stability, and allow photoacoustic imaging and synergistic photothermal/chemotherapy of cancer. Under 808 nm laser irradiation, the nanosheets have strong absorption in the near-infrared region, and high photothermal conversion efficiency (∼63.91%). Using DOX as a model drug, the IL-Ti3C2Tx MXene@DOX nanosheets exhibited high drug loading capacity and pH-/photosensitivity, which will further promote the drug release of the nanosheets in an acidic tumor microenvironment and under 808 nm laser irradiation. In vitro and in vivo experiments showed that IL-Ti3C2Tx MXene@DOX has good biological safety, allows remarkable photoacoustic imaging, and can effectively kill cancer cells with synergistic photothermal/chemotherapy. Therefore, IL-Ti3C2Tx MXene nanosheets are expected to provide powerful and useful two-dimensional nanoplatforms for various biomedical applications.


Assuntos
Líquidos Iônicos , Neoplasias , Técnicas Fotoacústicas , Liberação Controlada de Fármacos , Humanos , Neoplasias/terapia , Técnicas Fotoacústicas/métodos , Titânio , Microambiente Tumoral
8.
J Biomed Opt ; 27(7)2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35043610

RESUMO

SIGNIFICANCE: Time-domain functional near-infrared spectroscopy (TD-fNIRS) has been considered as the gold standard of noninvasive optical brain imaging devices. However, due to the high cost, complexity, and large form factor, it has not been as widely adopted as continuous wave NIRS systems. AIM: Kernel Flow is a TD-fNIRS system that has been designed to break through these limitations by maintaining the performance of a research grade TD-fNIRS system while integrating all of the components into a small modular device. APPROACH: The Kernel Flow modules are built around miniaturized laser drivers, custom integrated circuits, and specialized detectors. The modules can be assembled into a system with dense channel coverage over the entire head. RESULTS: We show performance similar to benchtop systems with our miniaturized device as characterized by standardized tissue and optical phantom protocols for TD-fNIRS and human neuroscience results. CONCLUSIONS: The miniaturized design of the Kernel Flow system allows for broader applications of TD-fNIRS.


Assuntos
Encéfalo , Espectroscopia de Luz Próxima ao Infravermelho , Encéfalo/diagnóstico por imagem , Humanos , Espectroscopia de Luz Próxima ao Infravermelho/métodos
9.
Nanomicro Lett ; 14(1): 44, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-35020069

RESUMO

HIGHLIGHTS: A novel amide-based nonflammable electrolyte is proposed. The formation mechanism and solvation chemistry are investigated by molecular dynamics simulations and density functional theory. An inorganic/organic-rich solid electrolyte interphase with an abundance of LiF, Li3N and Li-N-C is in situ formed, leading to spherical lithium deposition. The amide-based electrolyte can enable stable cycling performance at room temperature and 60 ℃. The formation of lithium dendrites and the safety hazards arising from flammable liquid electrolytes have seriously hindered the development of high-energy-density lithium metal batteries. Herein, an emerging amide-based electrolyte is proposed, containing LiTFSI and butyrolactam in different molar ratios. 1,1,2,2-Tetrafluoroethyl-2,2,3,3-tetrafluoropropylether and fluoroethylene carbonate are introduced into the amide-based electrolyte as counter solvent and additives. The well-designed amide-based electrolyte possesses nonflammability, high ionic conductivity, high thermal stability and electrochemical stability (> 4.7 V). Besides, an inorganic/organic-rich solid electrolyte interphase with an abundance of LiF, Li3N and Li-N-C is in situ formed, leading to spherical lithium deposition. The formation mechanism and solvation chemistry of amide-based electrolyte are further investigated by molecular dynamics simulations and density functional theory. When applied in Li metal batteries with LiFePO4 and LiMn2O4 cathode, the amide-based electrolyte can enable stable cycling performance at room temperature and 60 ℃. This study provides a new insight into the development of amide-based electrolytes for lithium metal batteries.

10.
Small ; 17(50): e2103052, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34719844

RESUMO

Manganese dioxide (MnO2 ), with naturally abundant crystal phases, is one of the most active candidates for toluene degradation. However, it remains ambiguous and controversial of the phase-activity relationship and the origin of the catalytic activity of these multiphase MnO2 . In this study, six types of MnO2 with crystal phases corresponding to α-, ß-, γ-, ε-, λ-, and δ-MnO2 are prepared, and their catalytic activity toward ozone-assisted catalytic oxidation of toluene at room temperature are studied, which follow the order of δ-MnO2  > α-MnO2  > ε-MnO2  > γ-MnO2  > λ-MnO2  > ß-MnO2 . Further investigation of the specific oxygen species with the toluene oxidation activity indicates that high catalytic activity of MnO2 is originated from the rich oxygen vacancy and the strong mobility of oxygen species. This work illustrates the important role of crystal phase in determining the oxygen vacancies' density and the mobility of oxygen species, thus influencing the catalytic activity of MnO2 catalysts, which sheds light on strategies of rational design and synthesis of multiphase MnO2 catalysts for volatile organic pollutants' (VOCs) degradation.


Assuntos
Nanoestruturas , Ozônio , Catálise , Compostos de Manganês , Óxidos , Tolueno
11.
Small ; 17(46): e2100946, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34323354

RESUMO

Research on 2D nanomaterials is still in its early stages. Most studies have focused on elucidating the unique properties of the materials, whereas only few reports have described the biomedical applications of 2D nanomaterials. Recently, important questions about the interaction of 2D MXene nanomaterials with biological components have been raised. 2D MXenes are monolayer atomic nanosheets derived from MAX phase ceramics. As a new type of inorganic nanosystems, they are being widely used in biology and biomedicine. This review introduces the latest developments in 2D MXenes for the most advanced biomedical applications, including preparation and surface modification strategies, treatment modes, drug delivery, antibacterial activity, bioimaging, sensing, and biocompatibility. Besides, this review also discusses the current development trends and prospects of 2D inorganic nanosheets for further clinical applications. These emerging 2D inorganic MXenes will play an important role in next-generation cancer treatments.


Assuntos
Nanoestruturas , Antibacterianos/farmacologia , Sistemas de Liberação de Medicamentos
12.
Chem Commun (Camb) ; 57(16): 2049-2052, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33507178

RESUMO

Unique Co, Fe codoped holey carbon nanosheets with high surface area and abundant bimetal single atoms (CoFe@HNSs) exhibited remarkable bifunctional oxygen electrocatalytic activity (0.704 V) with very positive half-wave potential (0.897 V) for the ORR and small potential (1.601 V) to drive 10 mA cm-2 for the OER, outperforming commercial Pt/C and IrO2, respectively. Furthermore, as the air-cathode for rechargeable Zn-air batteries, the CoFe@HNS based device exhibits a high-power density of 131.3 mW cm-2 and long-term stability over 140 h, indicating the attractive potential of CoFe@HNSs applied in energy storage and conversion.

13.
ACS Appl Mater Interfaces ; 12(36): 40541-40547, 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32786243

RESUMO

A significant number of challenges are encountered when developing biocidal agents with high throwing capacity for biosafety applications. Now a three-dimensional metal-organic framework (3D MOF) {MOF (2), [Cu(atrz)(IO3)2]n (atrz = 4,4'-azo-1,2,4-triazole)} was obtained using a postsynthetic method from MOF (1) {[Cu(atrz)3(NO3)2]n}. Benefitting from the oxygen-rich and small volume of the iodate (IO3) ligands (2.73 Å) in MOF (2) compared to the atrz ligand (7.70 Å) in MOF (1), the density of MOF (2) is 3.168 g cm-3, nearly twice that of its precursor. Its detonation velocity of 7271 ms-1 exceeds that of TNT (trinitrotoluene) and its detonation pressure of 40.6 GPa is superior to that of HMX (cyclotetramethylenetetranitramine) (1,3,5,7-tetranitro-1,3,5,7-tetrazoctane, 39.2 Gpa), which are the highest detonation properties for a biocidal agent. Its superior detonation performance results in its main product, I2, being distributed over a wide area, markedly reducing the diffusion of harmful microorganisms. This study offers novel insight not only for high-energy-density materials but also for huge potential applications as biocidal agents.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Estruturas Metalorgânicas/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Ligantes , Estruturas Metalorgânicas/síntese química , Estruturas Metalorgânicas/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Propriedades de Superfície
14.
Ultrason Sonochem ; 63: 104915, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31945581

RESUMO

An ultrasonication-assisted synthesis of alcohol-based deep eutectic solvents (DESs) is described. Several DESs were synthesized simultaneously under the same conditions. The prepared DESs were used for the extraction of gingerols from ginger powder via ultrasonication-assisted extraction. Notably, some of the prepared DESs exhibited superior extraction performance than those in traditional organic solvents. The viscosity of the DESs, which was suggested to be typically lower than 100 mPa*s had a critical effect on extraction performance. However, the higher gingerol contents in the extracts did not translate to higher active antioxidant abilities. The extraction temperature was found to be a key determinant of the antioxidant capability of the extracted gingerols while the use of higher temperatures (>50 °C) induced degradation and loss of phenolic compounds during extraction. Response surface methodology was applied for determining the optimal extraction conditions to achieve maximum antioxidant capacity with suitable gingerol content. All compounds used for the preparation of the DESs in this study have been widely employed in cosmetic and pharmaceutical fields. Therefore, the extracts in these DES solutions can be considered for direct application development without further product isolation.


Assuntos
Álcoois/química , Extratos Vegetais/isolamento & purificação , Solventes/química , Sonicação , Zingiber officinale/química , Antioxidantes/química , Benzotiazóis/química , Ácidos Sulfônicos/química
15.
ACS Biomater Sci Eng ; 6(7): 4106-4115, 2020 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-33463311

RESUMO

Currently, available nanoscale anticancer drug delivery systems have low targeting and release efficiency, limiting their therapeutic effects. Thus, tumor-targeting nanocarriers for self-assembly of amphiphilic polymer-drug conjugates are urgently needed to improve drug targeting and treatment efficacy. Here, we report the construction of a stable, reduction-sensitive prodrug conjugate based on hyaluronic acid-grafted pH-sensitive doxorubicin (DOX). The amphiphilic prodrug copolymer self-assembled into spherical nanoparticles in aqueous solution and exhibited an average diameter of 150 nm. Prodrug micelles were stable in a normal physiological environment and achieve selective and rapid release under acidic pH and/or high reduction conditions. Cell Counting Kit-8, flow cytometry, and live cell imaging assays showed that the prodrug had high targeting and antitumor activity against CD44 receptors. Moreover, in vivo pharmacokinetics and biodistribution studies showed that the prodrug had a longer circulation time in BALB/c mice and higher accumulation in 4T1 tumors. Interestingly, the prodrug could effectively treat tumors with few side effects. These results showed that the DOX prodrug micelles developed in this study may have great potential in targeted therapy.


Assuntos
Nanopartículas , Neoplasias , Pró-Fármacos , Animais , Sistemas de Liberação de Medicamentos , Ácido Hialurônico , Camundongos , Camundongos Endogâmicos BALB C , Neoplasias/tratamento farmacológico , Oxirredução , Polímeros , Distribuição Tecidual
16.
Materials (Basel) ; 11(10)2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30336617

RESUMO

Subsphaeroidal SiC/polymer composite granules with good flowability for additive manufacturing/3D printing of SiC were prepared by ball milling with surface modification using polyvinyl butyral (PVB). PVB adheres to the particle surface of SiC to form a crosslinked network structure and keeps them combined with each other into light aggregates. The effects of PVB on the shape, size, phase composition, distribution and flowability of the polymer-ceramic composite powder were investigated in detail. Results show that the composite powder material has good laser absorptivity at wavelengths of lower than 500 nm.

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