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1.
ACS Nano ; 18(12): 9053-9062, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38465964

RESUMO

Photoreceptor cells of vertebrates feature ultrastructural membranes interspersed with abundant photosensitive ion pumps to boost signal generation and realize high gain in dim light. In light of this, superstructured optoionic heterojunctions (SSOHs) with cation-selective nanochannels are developed for manipulating photo-driven ion pumping. A template-directed bottom-up strategy is adopted to sequentially assemble graphene oxide (GO) and PEDOT:PSS into heterogeneous membranes with sculptured superstructures, which feature programmable variation in membrane topography and contain a donor-acceptor interface capable of maintaining electron-hole separation upon photoillumination. Such elaborate design endows SSOHs with a much higher magnitude of photo-driven ion flux against a concentration gradient in contrast to conventional optoionic membranes with planar configuration. This can be ascribed to the buildup of an enhanced transmembrane potential owing to the effective separation of photogenerated carriers at the heterojunction interface and the increase of energy input from photoillumination due to a synergistic effect of reflection reduction, broad-angle absorption, and wide-waveband absorption. This work unlocks the significance of membrane topographies in photo-driven transmembrane transportation and proposes such a universal prototype that could be extended to other optoionic membranes to develop high-performance artificial ion pumps for energy conversion and sensing.


Assuntos
Elétrons , Bombas de Íon , Animais , Potenciais da Membrana , Meios de Transporte , Células Fotorreceptoras
2.
Sci Adv ; 10(7): eadk5444, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363838

RESUMO

Achieving high-contrast tricolor emissive regulation of a single-component molecule using a single type of external stimulus is highly desirable but challenging. In the present study, we report a symmetric acceptor-donor-acceptor (A-D-A)-type aggregation-induced emission-active luminogen, which displays a sequential high-contrast fluorescence switching just by anisotropic mechanical grinding. Specifically, upon light grinding, an orange-yellow-to-blue hypsochromic mechanofluorochromic response with a distinct color contrast (change in the maximum emission wavelength, Δλem,max = 122 nm) is noticed, and the slightly ground solid exhibits a blue-to-red high-contrast (Δλem,max = 185 nm) bathochromic mechanofluorochromic conversion upon vigorous grinding. Thus, using a single luminogen developed here, we can realize wide-range (Δλem,max > 100 nm) hypso- and bathochromic fluorescence mechanochromisms simultaneously. The tricolored mechanofluorochromic phenomenon is attributed to two different morphological transitions involving crystalline-to-crystalline and crystalline-to-amorphous states. Furthermore, three information anticounterfeiting systems are developed using the luminogen presented here.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 311: 123979, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38310742

RESUMO

High-performance luminescent gold(I) complexes have attracted considerable attention due to their potential applications in various fields, but their construction is a significantly challenging task. Herein, we designed and synthesized a series of novel dinuclear gold(I) complexes 1-4 based on 1,2-bis(diphenylphosphino)benzene and 1,4-bis(diphenylphosphino)benzene frameworks, where para-substitutions of benzene ring were employed for comparison and bulky t-butyl groups were introduced into carbazole ligands to assist flexibly regulating the aurophilicity. Among them, the structure of complex 1 was confirmed by single-crystal X-ray diffraction, and all the complexes exhibited typical aggregation-induced emission characteristics. Due to the construction of intramolecular aurophilicity and the formation of molecular clusters, noticeable enhancement of the luminescent efficiency was achieved for the core complex 1. Together with the introduction of flexible t-butyl groups, good responsiveness towards external mechanical force and solvent vapors were also realized. Moreover, the specific bioimaging ability of complex 1 towards cancer cells was demonstrated. Thus, this work presents the crucial capability of aurophilic manipulation in tuning the luminescence and smart behaviors of gold complexes, and it will open a new route to developing high-performance luminescent materials.

4.
Chem Asian J ; 19(2): e202300860, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37997007

RESUMO

In recent years, the field of organometallic chemistry has made a great progress and diverse types of metallaaromatics have successively been reported. In those studies, incorporation of ligated osmium centers into metallaaromatic systems played a prominent role. The reviewed literature documents that certain metallaaromatics with unconventional photophysical properties, redox and electronic transport properties and magnetism, have potential to be widely used in diverse practical applications, with selected examples of amino acid and fluoride anion identification, photothermal effects, functional materials, photodynamic therapy (PDT) in biomedicine, single-molecule junction conductors, and electron-transport layer materials (ETLs) in solar cells.

5.
Rev Sci Instrum ; 94(12)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38117197

RESUMO

The utilization of a low-frequency (<200 MHz) RF system in storage facilitates the attainment of ultra-low emittances in synchrotron light sources through on-axis injection. This paper focuses on the development of a low-frequency normal conducting (NC) cavity with higher-order mode (HOM) damping for fourth-generation synchrotron light sources. We propose a novel approach to achieve efficient HOM damping in a NC cavity by optimizing the lowest frequency HOM and implementing a beam-line absorber. Notably, unlike conventional NC cavities, the presence of a large beam tube for the beam-line absorber does not compromise the accelerating performance in a coaxial resonant cavity, enabling effective HOM damping while maintaining a high shunt impedance. Through simulations, the prototype design of a 166.6 MHz HOM-damped cavity demonstrates a fundamental mode impedance of ∼8 MΩ, with longitudinal and transverse HOM impedances below 2.0 and 50 kΩ/m, respectively.

6.
ChemMedChem ; 18(15): e202300204, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37193853

RESUMO

Cyanines in the near-infrared region are a typical example of a classic fluorescent dye that has garnered significant attention and widespread use in the life sciences and biotechnology. Their character to form assemblies or aggregates has inspired the development of various functional cyanine dye aggregates in phototherapy. This article provides a brief summary of the strategies used to prepare these cyanine dye aggregates. The reports in this concept suggest that the self-assembly of cyanine dyes can enhance their photostability, opening up new possibilities for their application in phototherapy. This concept may encourage researchers to explore the development of functional fluorescent dye aggregates further.


Assuntos
Corantes Fluorescentes , Quinolinas , Carbocianinas , Fototerapia
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 292: 122427, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36764141

RESUMO

In this work, two novel luminescent molecules containing distorted phenothiazine-S-oxide and phenothiazine-S,S dioxide skeletons were synthesized by oxidation reactions using different oxidants (m-chloroperoxybenzoic acid, acetic acid /hydrogen peroxide). The target compounds were all confirmed by 1H NMR, 13C NMR and EI-MS. Combined with the results of UV-vis absorption spectra and fluorescence emission spectra, we found that the different oxidation states of S-atom, from sulfide (+2) to sulfoxide (+4) and sulfone (+6), led to the blue, yellow-green and yellowish fluorescence of these compounds in the solid states. Subsequent studies showed that the molecule containing the phenothiazine-S-oxide skeleton exhibited obvious solvatochromism, and the increase of solvent polarity induced a red-shift in the emission wavelength. Moreover, this molecule also exhibited a rare self-recovery mechanochromatic behavior. In addition, these properties were further confirmed by theoretical calculations and X-ray single-crystal diffraction analysis.

8.
Angew Chem Int Ed Engl ; 62(3): e202216109, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36409066

RESUMO

The cationic nature of heptamethine cyanines gives them the capacity to form aggregates with salts by electrostatic interactions. In this work, NaCl promoted J-aggregate formation of aza-coating heptamethine cyanines is explored. NaCl can induce the N-benzyloxycarbonyl Cy-CO2 Bz to assemble into a J-aggregate having an absorption at 890 nm. Its excellent fluorescence response to NaCl implies that it has great potential for use as a probe for tracing salt stress in plants. Moreover, NaCl also promotes formation of J-aggregates from the N-ethyloxycarbonyl Cy-CO2 Et. The aggregate shows an intense absorption at 910 nm compared to the monomer which absorbs at 766 nm. Its J-aggregated form can serve as a photothermal agent. And the photothermal conversion efficiency is increased from 29.37 % to 57.59 %. This effort leads to the development of two applications of new cyanine J-aggregates including one for tracing salt stress of plants and the other for promoting photothermal therapy of tumors.


Assuntos
Neoplasias , Cloreto de Sódio , Humanos , Cloreto de Sódio/farmacologia , Terapia Fototérmica , Dióxido de Carbono , Corantes
9.
ACS Nano ; 16(11): 17613-17640, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36322865

RESUMO

Design elements extracted from biological ion channels guide the engineering of artificial nanofluidic membranes for efficient ionic transport and spawn biomimetic devices with great potential in many cutting-edge areas. In this context, polymeric nanofluidic membranes can be especially attractive because of their inherent flexibility and benign processability, which facilitate massive fabrication and facile device integration for large-scale applications. Herein, the state-of-the-art achievements of polymeric nanofluidic membranes are systematically summarized. Theoretical fundamentals underlying both biological and synthetic ion channels are introduced. The advances of engineering polymeric nanofluidic membranes are then detailed from aspects of structural design, material construction, and chemical functionalization, emphasizing their broad chemical and reticular/topological variety as well as considerable property tunability. After that, this Review expands on examples of evolving these polymeric membranes into macroscopic devices and their potentials in addressing compelling issues in energy conversion and storage systems where efficient ion transport is highly desirable. Finally, a brief outlook on possible future developments in this field is provided.


Assuntos
Materiais Biomiméticos , Biomimética , Transporte de Íons , Polímeros/química , Materiais Biomiméticos/química , Membranas Artificiais , Canais Iônicos/metabolismo
10.
J Vis Exp ; (181)2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35343961

RESUMO

Berberine (BBR) is an isoquinoline alkaloid isolated from Coptis chinensis and possesses valuable pharmacological activities, including anti-inflammatory, anti-tumor, and alleviating several complications of type 2 diabetes mellitus (T2DM). However, the role of BBR in regulating diabetic tendon injury remains poorly understood. In this study, a rat model of T2DM was constructed, and cell apoptosis and autophagy were assessed in tendon tissues after BBR treatment through TdT-Mediated dUTP nick-end labeling (TUNEL) assay and immunohistochemical analysis. Tendon fibroblasts were obtained from the rat Achilles tendon, and the role of BBR in regulating cell apoptosis, the production of inflammatory cytokines, and autophagy activation were assessed using flow cytometry, quantitative real-time PCR (qRT-PCR), and western blot analysis. We demonstrated that BBR treatment significantly increased autophagy activation and decreased cell apoptosis in tendon tissues of T2DM rats. In tendon fibroblasts, BBR repressed High glucose (HG)-induced cell apoptosis and production of proinflammatory cytokines. HG treatment resulted in a decrease of autophagy activation in tendon fibroblasts, whereas BBR restored autophagy activation. More important, pharmacological inhibition of autophagy by 3-MA weakened the protective effects of BBR against HG-induced tendon fibroblasts injury. Taken together, the current results demonstrate that BBR helps relieve diabetic tendon injury by activating autophagy of tendon fibroblasts.


Assuntos
Berberina , Diabetes Mellitus Tipo 2 , Traumatismos dos Tendões , Animais , Apoptose , Autofagia , Berberina/farmacologia , Fibroblastos , Ratos , Tendões
11.
Biosci Rep ; 42(3)2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35293974

RESUMO

Diabetic foot ulcer (DFU) is a kind of common and disabling complication of Diabetes Mellitus (DM). Emerging studies have demonstrated that tendon fibroblasts play a crucial role in remodeling phase of wound healing. However, little is known about the mechanism underlying high glucose (HG)-induced decrease in tendon fibroblasts viability. In the present study, the rat models of DFU were established, and collagen deposition, autophagy activation and cell apoptosis in tendon tissues were assessed using Hematoxylin-Eosin (HE) staining, immunohistochemistry (IHC), and TdT-mediated dUTP Nick-End Labeling (TUNEL) assay, respectively. Tendon fibroblasts were isolated from Achilles tendon of the both limbs, and the effect of HG on autophagy activation in tendon fibroblasts was assessed using Western blot analysis, Cell Counting Kit-8 (CCK-8) assay, and flow cytometry. We found that cell apoptosis was increased significantly and autophagy activation was decreased in foot tendon tissues of DFU rats compared with normal tissues. The role of HG in regulating tendon fibroblasts viability was then investigated in vitro, and data showed that HG repressed cell viability and increased cell apoptosis. Furthermore, HG treatment reduced LC3-II expression and increased p62 expression, indicating that HG repressed autophagy activation of tendon fibroblasts. The autophagy activator rapamycin reversed the effect. More importantly, rapamycin alleviated the suppressive role of HG in tendon fibroblasts viability. Taken together, our data demonstrate that HG represses tendon fibroblasts proliferation by inhibiting autophagy activation in tendon injury.


Assuntos
Pé Diabético , Traumatismos dos Tendões , Animais , Apoptose , Autofagia , Proliferação de Células , Pé Diabético/metabolismo , Fibroblastos/metabolismo , Glucose/metabolismo , Ratos , Sirolimo/farmacologia , Traumatismos dos Tendões/metabolismo , Tendões/metabolismo
12.
Front Pharmacol ; 12: 714643, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34712134

RESUMO

This research was designed to analyze the composition of immune cells in obesity and identify novel and potent drugs for obesity management by epigenetic and transcriptomic conjoint analysis. DNA methylation data set (GSE166611) and mRNA expression microarray (GSE18897) were obtained from the Gene Expression Omnibus database. A total of 72 objects (35 obese samples and 37 controls) were included in the study. Immune cell composition analysis, drug repositioning, and gene set enrichment analysis (GSEA) were performed using CIBERSORT, connectivity map (CMap), and GSEA tools. Besides, we performed a single-cell RNA-seq of the immune cells from whole blood samples obtained from one obese patient and one healthy control. mRNA levels of drug target genes were analyzed by qPCR assay in blood samples from six patients and six healthy controls. Immune cell composition analysis found that CD8 + T cells and NK cells were significantly lower in the obese group. 11 drugs/compounds are considered to possess obesity-control potential, such as atorvastatin. Moreover, the expression of drug targets (STAT3, MCL1, PMAIP1, SOD2, FOX O 3, FOS, FKBP5) in obese patients were higher than those in controls. In conclusion, immune cells are potential therapeutic targets for obesity. Our results also contribute to accelerate research on drug development of obesity.

13.
Chemistry ; 27(59): 14645-14652, 2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34350652

RESUMO

A series of novel osmaindenes 1-6 bearing different substituents (CF3 , H, I, Br, OCH3 , N(Ph)2 ) has been synthesized by nucleophilic reaction of water with the corresponding aromatic osmanaphthalyne complexes. All osmaindenes 1-6 have been characterized by elemental analysis (EA) and nuclear magnetic resonance (NMR) spectroscopy, although the low solubilities of 3 and 4 precluded the accumulation of their 13 C NMR spectra. Osmaindenes 2, 3 and 5 have also been characterized by single-crystal X-ray diffraction analysis. Subsequently, through solid-state fluorescence spectroscopy, mechanochromic studies, and powder X-ray diffraction (XRD) analysis, we found that osmaindenes 1-6 fluoresce at wavelengths in the range 500-800 nm, while also displaying reversible mechanochromic properties. The solid-state fluorescence emission of 1 after grinding extends into the near-infrared region. This research provides new insight into the design and synthesis of metallic materials with excellent mechanochromic properties.

14.
Dalton Trans ; 50(22): 7744-7749, 2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-33988209

RESUMO

Luminophores with persistent room-temperature phosphorescence (p-RTP) or effective phosphorescent mechanochromism features have significant potential applications in the field of optoelectronic materials. Until now, p-RTP and remarkable phosphorescent mechanochromism phenomena have been observed in some luminescent molecules with different molecular structures. However, separately realizing p-RTP and high-contrast phosphorescent mechanochromism in different polymorphs from a single luminophore is still a valuable and challenging topic. In this work, two polymorphs 1B and 1YG of a new gold(i) complex with blue and yellow-green luminescence, respectively, are reported. Interestingly, 1B exhibits high-contrast phosphorescent mechanochromic behavior, while 1YG exhibits a persistent room-temperature phosphorescence effect. This is the first example of simultaneously obtaining double-purpose crystalline materials with a high-contrast phosphorescent mechanochromism or persistent room-temperature phosphorescence feature from a single luminophore.

15.
Chemistry ; 27(36): 9328-9335, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33871120

RESUMO

Members of a new class of complexes, 2(CF3 ), 2(H), 2(Br), 2(I), and 2(OCH3 ), have been synthesized in a one-pot method involving the treatment of osmanaphthalynes bearing corresponding substituents (1(CF3 ), 1(H), 1(Br), 1(I), and 1(OCH3 )) with trimethylphosphine (PMe3 ) and water. The main reaction process involves two steps, namely a ligand-exchange with trimethylphosphine and nucleophilic addition of water to the Os≡C bond of the osmanaphthalyne. The substituents have a significant influence on the rate of the reaction, as befits a nucleophilic addition. Fortunately, the key intermediate [1(OCH3 )]' could be successfully captured, and the detailed reaction mechanism has been explored with the aid of density functional theory (DFT) calculations, which were in excellent agreement with the experimental findings. All of the target complexes have been fully characterized by 1 H, 31 P{1 H}, and 13 C{1 H} NMR spectroscopy, high-resolution mass spectrometry, and elemental analysis.

16.
Cancer Med ; 10(8): 2763-2773, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33724697

RESUMO

OBJECTIVE: We aimed to evaluate the role of tumor size in predicting tumor risk for localized prostate cancer (PCa) patients undergoing radical prostatectomy (RP). METHODS: Twenty-five thousand, one hundred twenty-seven men with PCa receiving RP from 2010 to 2015 were extracted from the Surveillance, Epidemiology, and End Results database. Kaplan-Meier plots and multivariable Cox regression analyses were used to illustrate overall survival (OS) according to the tumor size. The tumor size was confirmed by postoperative pathology after RP. RESULTS: Among overall localized PCa, 84.6% were high-risk PCa, 9.2% were intermediate-risk PCa, and 6.2% were low-risk PCa. Multivariate analyses demonstrated that tumor size ≥21 mm was an independent risk predict factor of low-risk PCa (odds ratio [OR]: 11.940; 95% CI, 9.404-15.161; p < 0.001) and intermediate-risk PCa (OR: 1.887; 95% CI, 1.586-2.245; p < 0.001). Tumor sizes ≤5 mm significantly correlated with high-risk PCa (p < 0.001). Tumor size ≤5 mm had the worst OS in overall localized PCa and high-risk PCa (p < 0.001). CONCLUSIONS: In localized PCa, tumor sizes ≥21 mm may help predict low or intermediate-risk PCa, while tumor sizes ≤5 mm might help predict high-risk PCa. In clinical practice, we should be on high alert for patients with tumors size ≤5 mm due to its poor prognosis after RP.


Assuntos
Neoplasias da Próstata/patologia , Idoso , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Neoplasias da Próstata/mortalidade , Neoplasias da Próstata/cirurgia , Estudos Retrospectivos , Fatores de Risco , Programa de SEER
17.
Anal Chem ; 93(7): 3378-3385, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33560116

RESUMO

Thienoisoindigo as a popular conjugated skeleton has been constantly applied in the construction of organic optoelectronic materials. Exploring its new applications in fluorescent sensors and bioimaging is helpful to extend its potential. In this work, a thienoisoindigo fluorophore was first selected as a building block to be applied in the construction of the near-infrared fluorescent materials with an aggregation-induced emission manner through introducing triarylamine, thiophene-bridged triarylamine, and N,N-dimethyl styrene, respectively. These fluorescent agents showed the near-infrared emission and possessed typical aggregation-induced emission behavior. Although they had low band gaps and near-infrared emission, they presented remarkable photostability. Especially, thiophene-bridged triarylamine and N,N-dimethyl styrene-coated thienoisoindigos exhibited strong lysosomal targeting capability, and they could also serve for fluorescence imaging in vivo.


Assuntos
Diagnóstico por Imagem , Corantes Fluorescentes , Imagem Óptica
19.
Dalton Trans ; 49(46): 16877-16886, 2020 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-33180078

RESUMO

A series of bimetallic ruthenium vinyl complexes 1-5 bridged by oligoacenes were synthesized and characterized in this study. Comparative cyclic voltammetry results from 1-5 indicated that the first oxidation potential decreased gradually with the extension of conjugate ligands. Upon oxidation to singly oxidized species 1+-5+, rather small ν(CO) changes in the infrared (IR) spectra and the characteristic bands of metal-to-ligand charge transfer absorptions in the near IR (NIR) region predicted via time-dependent DFT calculations suggested that strong bridged ligands participate in redox processes. NIR absorptions were not observed in complexes 4+ and 5+ possibly because of instability in their twisted and noncoplanar geometry. Electron paramagnetic resonance results and spin density distribution demonstrated that the bridged localized degrees of 1+-5+ successively increased with the extension of oligoacene from benzene to tetracene. Further comparative analysis of neutral molecules and monocations to the aromaticity and π-electron density of bridge cores indicated a step-by-step transformation process from an aromatic to quinoidal radical upon oxidation.

20.
Org Biomol Chem ; 18(46): 9385-9397, 2020 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-33191410

RESUMO

Heptamethine cyanine dyes (Cy7) have attracted much attention in the field of biological application due to their unique structure and attractive near infrared (NIR) photophysical properties. In this review, the influences of different modification sites on the absorption characteristics, photostability, Stokes shift, fluorescence characteristics, water solubility, and singlet oxygen generation efficiency of this class of dyes are summarized, and the application development of the corresponding dyes in the field of biological application is introduced, which will provide a reference for the optimization and improvement of heptamethine cyanine dyes in the future.

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