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1.
Mater Horiz ; 8(2): 571-576, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34821273

RESUMO

We report the first demonstration using a stable π-radical as a versatile photosensitizer for hypoxia-overcoming photodynamic therapy. After self-assembling the radical molecules into radical nanoparticles (NPs), the NPs show good water dispersibility, good biocompatibility, broad near-infrared (NIR) absorption and emission at ∼800 nm. Significantly, the radical NPs remain stable in various biological mediums, after 100 days exposure to the ambient environment, and even after long-term laser irradiation, which is superior to many reported radical-based materials. More importantly, upon 635 nm laser irradiation, sufficient superoxide radical (O2-˙) generation and in vitro cytotoxicity were observed addressing the most important hurdle for successful PDT in the oxygen-deficient tumor microenvironment. In addition, the radical NPs are also demonstrated to have effective in vivo PDT efficacy, and excellent biosafety.

2.
Ecotoxicol Environ Saf ; 228: 112971, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34775343

RESUMO

The development and application of nano-biochar synthesized by ball milling technology is still challenging in the field of environmental remediation because of its higher activity with pollutants. The purpose of this study was to investigate the transport behavior of two kinds of biochar nanoparticles (nanobiochar (NBC) and nZVI-modified nanobiochar (nZVI-NBC)) and Cd2+ in clay mineral (kaolinite, illite, and montmorillonite)-coated quartz sand columns. The interaction between biochar nanoparticles and Cd2+ in saturated porous media was studied in cotransport experiments. Then, the effect of biochar nanoparticles on the release of Cd2+ in contaminated media was explored by elution experiments. The cotransport experiments showed that the mobility of Cd2+ was enhanced by two kinds of biochar nanoparticles, while the transport of biochar was limited due to the presence of Cd2+. The elution experiments showed that the transport of biochar nanoparticles can be inhibited by Cd2+ previously immobilized in the sand column, and Cd2+ can be rereleased by biochar nanoparticles. The rerelease ability of nZVI-NBC to Cd2+ is weaker than that of NBC because nZVI is more easily retained in the sand column after oxidation, thus strengthening the immobilization of Cd2+. In general, the recoveries of NBC, nZVI-NBC and Cd2+ in saturated porous media were reduced by the presence of clay minerals. The experimental results describing the stability of biochar nanoparticles in sand columns are consistent with those predicted by the Derjaguin-Landau-Verwey-Overbeek theory. The transport behavior of Cd2+ and biochar nanoparticles in sand columns can be well simulated by advection-dispersion-reaction. These findings reveal the interaction between biochar nanoparticles and heavy metals in the soil environment and provide new insights into the transport and fate of environmental remediation materials and pollutants in the underground environment.

3.
J Healthc Eng ; 2021: 4379623, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34608410

RESUMO

In recent years, the employment of college students is becoming more and more prominent; no matter for the society, universities, college students themselves, and their families have formed a huge pressure, in the current situation, the success rate of college students to start their own business is not high; one of the important reasons is that college students generally have defects in entrepreneurial psychology. Therefore, effective evaluation of college students' mental health under the environment of independent entrepreneurship is conducive to comprehensively improving the quality of talent training in colleges and universities. In this paper, we propose a novel three-channel multifeature fusion network based on neural network technology to identify and predict college students' mental health problems in the self-entrepreneurship environment. Specifically, we first extract the behavior characteristics, visual characteristics, and social relations as a three-channel network input. Second, in view of the behavior characteristic, we use the length of the memory deep context dependent on network access. In view of visual features, we use the convolution neural network to face emotional characteristics and characteristics of social relations. The feature concat strategy is used for feature fusion. The experimental results on real datasets show that the method in this paper is effective, and it is expected to propose a new solution for college students' mental health assessment.

4.
Nanoscale ; 13(26): 11525-11533, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34180928

RESUMO

II-VI semiconductor heterojunctions show huge potential for application in nanodevice fabrication due to their type-II alignments owing to the better spatial separation of electrons and holes. However, the hetero-epitaxial growth of high-quality heterostructures is still a challenge, especially for materials with large lattice mismatch. In this work, well-aligned single-crystalline ZnO/ZnS core/shell nanorod arrays were obtained by introducing an Al2O3 buffer layer. It is interesting that the nature of the ZnS layer varies with the thickness of the Al2O3 layer. When Al2O3 is less than 2 nm, the interaction between the substrate and epilayer is strong enough to penetrate through the buffer layer, enabling the growth of ZnS on Al2O3-coated ZnO nanorod arrays. On the basis of detailed characterization, a rational growth mechanism of the core/shell heterostructure is proposed, in which the Al2O3 interlayer can eliminate voids due to the Kirkendall effect around the interface and accommodate a misfit dislocation between the inner ZnO and outer ZnS, resulting in more sufficient strain relaxation in the epitaxy. In addition, cathodoluminescence measurements demonstrate that the optical properties of the ZnO/ZnS heterostructure could be effectively improved by taking advantage of the thin Al2O3. The I-V curves characterized by PeakForce tunneling atomic force microscopy reveal that the heterostructure shows a typical rectifying behavior and good photoresponse to ultraviolet light. These findings may provide a reasonable and effective strategy for the growth of highly lattice-mismatched heterostructure arrays buffered by the Al2O3 layer, broadening the options for fabricating heterojunctions and promoting their applications in optoelectronic devices.

5.
Inorg Chem ; 60(13): 9987-9995, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34114800

RESUMO

Hydrogen evolution reaction (HER) in alkaline medium is currently under scientific spotlight for generating clean H2 fuel from electrochemical water splitting. However, alkaline HER suffers from sluggish reaction kinetics because of the additional energy required for water dissociation from catalysts in contrast to acidic HER. Herein, we report the development of two-dimensional metal-organic framework (2D MOF) Ni-1,4-benzenedicarboxylic acid-based composite nanosheets for superior performance in HER electrocatalysis. Iron phthalocyanine (FePc) molecules are uniformly anchored on the ultrathin 2D Ni-MOF, showing a substantially increased current density, improved activity, and enhanced durability in alkaline HER. On account of the ultralarge specific surface of Ni-MOF and the coupling effects between FePc and 2D MOFs, the resultant nanosheet catalyst FePc@Ni-MOF exhibits a low overpotential (334 mV) and satisfactory long-term stability (10 h) at a current density of 10 mA·cm-2, which outperform those of pristine FePc, Ni-MOF, and the counterpart FePc@bulk-MOF. This study provides new insights into the synthesis of robust MOF-based nanosheet composites with high performance in catalysis.

6.
J Biol Inorg Chem ; 26(2-3): 205-216, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33544224

RESUMO

Two biologically inspired tetranuclear nickel complexes [Ni4(L-H)4(CH3COO)3]·Cl (1) and [Ni4(L-H)4(CH3COO)4]·2CH3OH (2) (L = di(pyridin-2-yl)methanediol) have been synthesized and investigated by a combination of X-ray crystallography, PXRD, electrochemistry, in-situ UV-Vis spectroelectrochemistry and DLS. Both of the two complexes feature a core composed of four Ni(II) ions with the same peripheral ligation provided by the anionic di(pyridin-2-yl)methanediol and MeCOO- ligands. Whereas, complex 1 possesses one distorted cubane-like [Ni4(µ3-O)4] core, while 2 has one extended butterfly-like [Ni4(µ3-O)2] core. The homogeneous electrocatalytic reactivity of the two water-soluble complexes for water oxidation have been thoroughly studied, which demonstrates that both of them can efficiently electrocatalyze water oxidation with high stability under alkaline conditions, at relatively low over-potentials (η) of 420-790 mV for 1 and 390-780 mV for 2, both in the pH range of 7.67-12.32, with the high TOF of about 139 s-1 (1) and 69 s-1 (2) at pH = 12.32, respectively. By a series of comparative experiments for complexes 1 and 2, we proposed that their crystal geometries play an important role in their electrocatalytic reactivity for water oxidation. We verified that biomimetic cubane geometry could promote OER catalysis with two very similar compounds for the first time. Compared with 2, the biomimetic cubane topology of 1 could promote OER catalysis by facilitating efficient charge delocalization and electron-transfer.


Assuntos
Complexos de Coordenação/química , Níquel/química , Água/química , Materiais Biomiméticos/química , Catálise , Eletroquímica , Concentração de Íons de Hidrogênio , Modelos Moleculares , Conformação Molecular , Oxirredução
7.
Circ Res ; 128(1): e1-e23, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33092465

RESUMO

RATIONALE: Previous translational studies implicate plasma extracellular microRNA-30d (miR-30d) as a biomarker in left ventricular remodeling and clinical outcome in heart failure (HF) patients, although precise mechanisms remain obscure. OBJECTIVE: To investigate the mechanism of miR-30d-mediated cardioprotection in HF. METHODS AND RESULTS: In rat and mouse models of ischemic HF, we show that miR-30d gain of function (genetic, lentivirus, or agomiR-mediated) improves cardiac function, decreases myocardial fibrosis, and attenuates cardiomyocyte (CM) apoptosis. Genetic or locked nucleic acid-based knock-down of miR-30d expression potentiates pathological left ventricular remodeling, with increased dysfunction, fibrosis, and cardiomyocyte death. RNA sequencing of in vitro miR-30d gain and loss of function, together with bioinformatic prediction and experimental validation in cardiac myocytes and fibroblasts, were used to identify and validate direct targets of miR-30d. miR-30d expression is selectively enriched in cardiomyocytes, induced by hypoxic stress and is acutely protective, targeting MAP4K4 (mitogen-associate protein kinase 4) to ameliorate apoptosis. Moreover, miR-30d is secreted primarily in extracellular vesicles by cardiomyocytes and inhibits fibroblast proliferation and activation by directly targeting integrin α5 in the acute phase via paracrine signaling to cardiac fibroblasts. In the chronic phase of ischemic remodeling, lower expression of miR-30d in the heart and plasma extracellular vesicles is associated with adverse remodeling in rodent models and human subjects and is linked to whole-blood expression of genes implicated in fibrosis and inflammation, consistent with observations in model systems. CONCLUSIONS: These findings provide the mechanistic underpinning for the cardioprotective association of miR-30d in human HF. More broadly, our findings support an emerging paradigm involving intercellular communication of extracellular vesicle-contained miRNAs (microRNAs) to transregulate distinct signaling pathways across cell types. Functionally validated RNA biomarkers and their signaling networks may warrant further investigation as novel therapeutic targets in HF.


Assuntos
MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Miocárdio/metabolismo , Comunicação Parácrina , Função Ventricular Esquerda , Remodelação Ventricular , Animais , Apoptose , Células Cultivadas , Modelos Animais de Doenças , Vesículas Extracelulares/genética , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Fibroblastos/metabolismo , Fibroblastos/patologia , Fibrose , Regulação da Expressão Gênica , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/genética , Infarto do Miocárdio/genética , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Ratos Sprague-Dawley , Ratos Transgênicos , Transdução de Sinais
8.
Sensors (Basel) ; 20(23)2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33291327

RESUMO

The traditional predictive model for remaining useful life predictions cannot achieve adaptiveness, which is one of the main problems of said predictions. This paper proposes a LightGBM-based Remaining useful life (RUL) prediction method which considers the process and machining state. Firstly, a multi-information fusion strategy that can effectively reduce the model error and improve the generalization ability of the model is proposed. Secondly, a preprocessing method for improving the time precision and small-time granularity of feature extraction while avoiding dimensional explosion is proposed. Thirdly, an importance coefficient and a custom loss function related to the process and machining state are proposed. Finally, using the processing data of actual tool life cycle, through five evaluation indexes and 25 sets of contrast experiments, the superiority and effectiveness of the proposed method are verified.

9.
Small ; 16(40): e2003782, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32877008

RESUMO

Ordered intermetallic nanomaterials with a well-defined crystal structure and fixed stoichiometry facilitate the predictable control of their electronic structure and catalytic performance. To obtain the thermodynamically stable intermetallic structures, the conventional approaches with high-temperature annealing are still far from satisfactory, because of annealing-induced aggregation and sintering of nanomaterials. Herein, a general wet-chemical method is developed to synthesize a series of noble metal-based intermetallic nanocrystals, including hexagonal close-packed (hcp) PtBi nanoplates, face-centered cubic (fcc) Pd3 Pb nanocubes, and hcp Pd2.5 Bi1.5 nanoparticles. During the synthetic process, Br- ions play two important roles for the formation of ordered intermetallic structures: i) Br- ions can coordinate with the metal ions to decrease their reduction potentials thus slowing down the reduction kinetics. ii) Br- ions can combine with molecular oxygen to generate an oxidative etching effect, hence reconstructing the atom arrangement, which is beneficial for the formation of the intermetallic structure. As a proof-of-concept application, Pd3 Pb nanocubes are used as electrocatalysts for ethanol and methanol oxidation reactions, which exhibit significantly improved electrochemical performance compared with the commercial Pd black catalyst.

10.
ACS Nano ; 14(8): 9917-9928, 2020 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-32706236

RESUMO

Effective multimodality phototheranostics under deep-penetration laser excitation is highly desired for tumor medicine, which is still at a deadlock due to lack of versatile photosensitizers with absorption located in the long-wavelength region. Herein, we demonstrate a stable organic photosensitizer nanoparticle based on molecular engineering of benzo[c]thiophene (BT)-based photoactivated molecules with strong wavelength-tunable absorption in the near-infrared region. Via molecular design, the absorption and singlet oxygen generation of BT molecules would be reliably tuned. Importantly, the nanoparticles with a red-shifted absorption peak of 843 nm not only show over 10-fold reactive oxygen species yield compared with indocyanine green but also demonstrate a notable photothermal effect and photoacoustic signal upon 808 nm excitation. The in vitro and in vivo experiments substantiate good multimodal anticancer efficacy and imaging performance of BT theranostics. This work provides an organic photosensitizer nanoparticle with long-wavelength excitation and high photoenergy conversion efficiency for multimodality phototherapy.


Assuntos
Nanopartículas , Fármacos Fotossensibilizantes , Fototerapia , Espécies Reativas de Oxigênio , Nanomedicina Teranóstica
12.
Adv Mater ; 32(19): e1906238, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32173918

RESUMO

Two-dimensional (2D) palladium diselenide (PdSe2 ) has strong interlayer coupling and a puckered pentagonal structure, leading to remarkable layer-dependent electronic structures and highly anisotropic in-plane optical and electronic properties. However, the lack of high-quality, 2D PdSe2 crystals grown by bottom-up approaches limits the study of their exotic properties and practical applications. In this work, chemical vapor deposition growth of highly crystalline few-layer (≥2 layers) PdSe2 crystals on various substrates is reported. The high quality of the PdSe2 crystals is confirmed by low-frequency Raman spectroscopy, scanning transmission electron microscopy, and electrical characterization. In addition, strong in-plane optical anisotropy is demonstrated via polarized Raman spectroscopy and second-harmonic generation maps of the PdSe2 flakes. A theoretical model based on kinetic Wulff construction theory and density functional theory calculations is developed and described the observed evolution of "square-like" shaped PdSe2 crystals into rhombus due to the higher nucleation barriers for stable attachment on the (1,1) and (1,-1) edges, which results in their slower growth rates. Few-layer PdSe2 field-effect transistors reveal tunable ambipolar charge carrier conduction with an electron mobility up to ≈294 cm2 V-1 s-1 , which is comparable to that of exfoliated PdSe2 , indicating the promise of this anisotropic 2D material for electronics.

13.
ACS Appl Mater Interfaces ; 12(7): 8411-8421, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-31976643

RESUMO

High sensitivity, low limit of detection (LOD), and short response and recovery times at room temperature (RT) are critical for gas sensors. For NO2, different binary metal oxide-based sensors were developed to achieve superior performance at elevated temperatures instead of RT. Herein, we report on CuO@CuO and Cu3Mo2O9@CuO sensors with CuO and Cu3Mo2O9 micro/nanorods vertically aligned on the CuO layers, which were directly fabricated using a facile, low-cost, and catalyst-free chemical vapor deposition (CVD) technique. Their sensing performance tests revealed that the Cu3Mo2O9@CuO p-p heterojunction sensors exhibited a high response of 160% to 5 ppm NO2, an excellent sensitivity of 50% ppm-1, a low LOD of 2.30 ppb, a short response time of 49 s, and a rapid recovery of 241 s at RT, obviously better than those for CuO@CuO sensors. The superior performance of Cu3Mo2O9@CuO sensors could be attributed to the Schottky heterojunction formed between p-Cu3Mo2O9 micro/nanorods and p-CuO films, the catalytic effect, and the anisotropic nature of Cu3Mo2O9 micro/nanorods. This study not only provides a simple, low-cost, and batchable fabrication method of homo/heterojunction sensors with micro/nanorods vertically aligned on films but also opens an avenue for sensor design by tuning the Schottky barrier height to enhance RT performance.

14.
Small ; 16(1): e1905184, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31788959

RESUMO

Currently, there is tremendous interest in the discovery of new and improved photothermal agents for near-infrared (NIR)-driven cancer therapy. Herein, a series of novel photothermal agents, comprising copper nanoparticles supported on defective porous carbon polyhedra are successfully prepared by heating a Cu-BTC metal-organic framework (MOF) precursor at different temperatures (t) in the range 400-900 °C under an argon atmosphere. The copper nanoparticle size and carbon defect concentration in the obtained products (denoted herein as Cu@CPP-t) increase with synthesis temperature, thus imparting the Cu@CPP-t samples with distinct NIR absorption properties and photothermal heating responses. The Cu@CPP-800 sample shows a remarkable photothermal conversion efficiency of 48.5% under 808 nm laser irradiation, representing one of the highest photothermal efficiencies yet reported for a carbon-based photothermal agent. In vivo experiments conducted with tumor bearing nude Balb/c mice confirm the efficacy of Cu@CPP-800 as a very promising NIR-driven phototherapy agent for cancer treatment. Results encourage the wider use of MOFs as low cost precursors for the synthesis of carbon-supported metal nanoparticle composites for photothermal therapy.


Assuntos
Carbono/química , Cobre/química , Raios Infravermelhos , Nanopartículas Metálicas/química , Neoplasias/terapia , Fototerapia , Porosidade , Linhagem Celular Tumoral , Humanos , Estruturas Metalorgânicas/química , Difração de Raios X
15.
ACS Appl Mater Interfaces ; 11(44): 41051-41061, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31602976

RESUMO

A recent breakthrough in the discovery of thermally activated delayed fluorescence (TADF) emitters characterized by small single-triplet energy offsets (ΔEST) offers a wealth of new opportunities to exploit high-performance metal-free photosensitizers. In this report, two intrinsically cancer-mitochondria-targeted TADF emitters-based nanoparticles (TADF NPs) have been developed for two-photon-activated photodynamic therapy (PDT) and fluorescence imaging. The as-prepared TADF NPs integrate the merits of (1) high 1O2 quantum yield of 52%, (2) sufficient near-infrared light penetration depth due to two-photon activation, and (3) excellent structure-inherent mitochondria-targeting capabilities without extra chemical or physical modifications, inducing remarkable endogenous mitochondria-specific reactive oxygen species production and excellent cancer-cell-killing ability at an ultralow light irradiance. We believe that the development of such intrinsically multifunctional TADF NPs stemming from a single molecule will provide new insights into exploration of novel PDT agents with strong photosensitizing ability for various biomedical applications.


Assuntos
Corantes Fluorescentes/química , Mitocôndrias/patologia , Nanopartículas/química , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Humanos , Raios Infravermelhos , Microscopia Confocal , Microscopia de Fluorescência por Excitação Multifotônica , Mitocôndrias/efeitos dos fármacos , Nanopartículas/toxicidade , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fotoquimioterapia , Fótons , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Teoria Quântica , Oxigênio Singlete/metabolismo
16.
Rev Sci Instrum ; 90(8): 083904, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31472619

RESUMO

We describe the design, fabrication, and use of a ceramic bulk preparation system, applied to the very high-throughput batching and molding for solid ceramic powders. Through the principle on precise volume controlling of powder materials, up to 100 ceramic block samples with maximum 6 components could be prepared in one time through 100 channels with Φ5 × 5 mm forming molds. The automatic control stage has been built to fill the target powder in a limited size and discrete small volume range. Here, we have designed a mechanical structure and software program so that rotary silo powder feeding amount could be controlled at 5-100 ml/time and the feeding precision can reach 0.005 g. Finally, the equipment is verified by preparing several infrared ceramic samples of different components.

17.
Front Genet ; 10: 564, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31316543

RESUMO

Cardiac fibrosis is the pathological consequence of fibroblast proliferation and fibroblast-to-myofibroblast transition. As a new class of endogenous non-coding RNAs, circular RNAs (circRNAs) have been identified in many cardiovascular diseases including fibrosis, generally acting as microRNA (miRNA) sponges. Here, we report that the expression of circRNA-circNFIB was decreased in mice post-myocardial infarction heart samples, as well as in primary adult cardiac fibroblasts treated with TGF-ß. Forced expression of circNFIB decreased cell proliferation in both NIH/3T3 cells and primary adult fibroblasts as evidenced by EdU incorporation. Conversely, inhibition of circNFIB promoted adult fibroblast proliferation. Furthermore, circNFIB was identified as a miR-433 endogenous sponge. Overexpression of circNFIB could attenuate pro-proliferative effects induced by the miR-433 mimic while inhibition of circNFIB exhibited opposite results. Finally, upregulation of circNFIB also reversed the expression levels of target genes and downstream signaling pathways of miR-433. In conclusion, circNFIB is critical for protection against cardiac fibrosis. The circNFIB-miR-433 axis may represent a novel therapeutic approach for treatment of fibrotic diseases.

18.
Eur J Pharmacol ; 851: 151-160, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30796903

RESUMO

It is generally considered that enteric neuropathy is one of the causative factors in diabetic gastroparesis. Our previous study demonstrated that there is a loss of NOS neurons in diabetic mice. However, the underlying mechanism remains unclear. The present study was designed to clarify the relationship between neuronal P2X7R and NOS neuron damage. The effect of P2X7R on diabetes-induced gastric NOS neurons damage and its mechanism were investigated by using quantitative RT-PCR,immunofluorescence, western blot, isometric force recording, intracellular calcium ([Ca2+]i) measurement and whole-cell patch clamp techniques. The immunohistochemistry and western blot results showed that nNOS expression was significantly down-regulated in diabetic mice, meanwhile, electric field stimulation-induced NOS sensitive relaxation was significantly suppressed. Myenteric neurons expressed P2X7R and pannexin1, and the mRNA and protein level of P2X7R and pannexin1 were up-regulated in diabetic mice. BzATP, a P2X7R activator, evoked [Ca2+]i increase in Hek293 cells with heterologous expression of P2X7R (Hek293-P2X7R cells) and the same dose of ATP-induced [Ca2+]i was more obvious in Hek293-P2X7R cells than in Hek293 cells. Application of BzATP activated an inward current of Hek293-P2X7R in a dose dependent manner. Hek293-P2X7R but not untransfected Hek293 cells could take up of YO-PRO-1. In addition, the uptake of YO-PRO-1 by Hek293-P2X7R was blocked by oxATP, a P2X7 antagonist and CBX, a pannexin1 inhibitor. The results suggest that the P2X7R of enteric neurons may be involved in diabetes-induced NOS neuron damage via combining with pannexin-1 to form transmembrane pores which induce macromolecular substances and calcium into the cells.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Mucosa Gástrica/metabolismo , Neurônios/metabolismo , Óxido Nítrico/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/farmacologia , Animais , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Cálcio/metabolismo , Fundo Gástrico/efeitos dos fármacos , Fundo Gástrico/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neurônios/efeitos dos fármacos , Neurônios/patologia , Óxido Nítrico Sintase Tipo I/metabolismo
19.
BMC Med ; 17(1): 42, 2019 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-30782145

RESUMO

BACKGROUND: Cathelicidins are a major group of natural antimicrobial peptides which play essential roles in regulating host defense and immunity. In addition to the antimicrobial and immunomodulatory activities, recent studies have reported the involvement of cathelicidins in cardiovascular diseases by regulating inflammatory response and microvascular dysfunction. However, the role of cathelicidins in myocardial apoptosis upon cardiac ischemia/reperfusion (I/R) injury remains largely unknown. METHODS: CRAMP (cathelicidin-related antimicrobial peptide) levels were measured in the heart and serum from I/R mice and in neonatal mouse cardiomyocytes treated with oxygen glucose deprivation/reperfusion (OGDR). Human serum cathelicidin antimicrobial peptide (LL-37) levels were measured in myocardial infarction (MI) patients. The role of CRAMP in myocardial apoptosis upon I/R injury was investigated in mice injected with the CRAMP peptide and in CRAMP knockout (KO) mice, as well as in OGDR-treated cardiomyocytes. RESULTS: We observed reduced CRAMP level in both heart and serum samples from I/R mice and in OGDR-treated cardiomyocytes, as well as reduced LL-37 level in MI patients. Knockdown of CRAMP enhanced cardiomyocyte apoptosis, and CRAMP KO mice displayed increased infarct size and myocardial apoptosis. In contrast, the CRAMP peptide reduced cardiomyocyte apoptosis and I/R injury. The CRAMP peptide inhibited cardiomyocyte apoptosis by activation of Akt and ERK1/2 and phosphorylation and nuclear export of FoxO3a. c-Jun was identified as a negative regulator of the CRAMP gene. Moreover, lower level of serum LL-37/neutrophil ratio was associated with readmission and/or death in MI patients during 1-year follow-up. CONCLUSIONS: CRAMP protects against cardiomyocyte apoptosis and cardiac I/R injury via activation of Akt and ERK and phosphorylation and nuclear export of FoxO3a. Increasing LL-37 might be a novel therapy for cardiac ischemic injury.


Assuntos
Anti-Infecciosos/uso terapêutico , Catelicidinas/uso terapêutico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Animais , Anti-Infecciosos/farmacologia , Catelicidinas/farmacologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
20.
ACS Appl Mater Interfaces ; 11(6): 6267-6275, 2019 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-30672683

RESUMO

In medical applications, two-dimensional nanomaterials have been widely studied on account of their intriguing properties such as good biocompatibility, stability, and multifunctionality. Herein, an ultrathin MnO2 nanosheet has been fabricated by a simplistic hydrothermal process. The high photothermal conversion performance (62.4%) can be attributed to the vacancy in the ultrathin MnO2 nanosheet, as confirmed by the extended X-ray absorption fine structure results and the density functional theory calculation, benefiting photoacoustic imaging-guided cancer therapy. This highly efficient vacancy-induced photothermal therapy has been reported for the first time. As a result, this work demonstrates that this ultrathin MnO2 nanosheet has a potential to construct a nanosystem for imaging-guided cancer therapy.


Assuntos
Compostos de Manganês/química , Nanoestruturas/química , Óxidos/química , Animais , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Peróxido de Hidrogênio/química , Raios Infravermelhos , Compostos de Manganês/uso terapêutico , Camundongos , Nanoestruturas/toxicidade , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Neoplasias/terapia , Óxidos/uso terapêutico , Fototerapia , Transplante Heterólogo
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