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1.
Analyst ; 144(6): 2166-2172, 2019 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-30762055

RESUMO

In this study, a functionalized ionic liquid (IL), 3-methyl-1-(ethoxycarbonylmethyl) imidazolium bis(trifluoromethylsulfonyl)-imide ([MimCH2COOCH3][NTf2]), was rationally designed and explored as an extraction solvent in dispersive liquid-liquid microextraction (DLLME) combined with ultra-high performance liquid chromatography (UHPLC) for the sensitive determination of organophosphorus pesticides (OPs). As π-π stacking interaction between the parent imidazolium cation core and the OPs is one of the most important factors, the proposed IL exhibited a high extraction efficiency. Moreover, during the DLLME process, a cloudy solution containing fine drops of [MimCH2COOCH3][NTf2] allowed for a larger contact area between the OPs and the IL, which accelerated the mass transfer, and therefore the enrichment could be realized in a rapid fashion. Under the optimal extraction conditions, the developed method was successfully applied in the analysis of OPs in environmental water samples with a high enrichment factor (more than 400), good recovery and reproducibility.

2.
Biochem Pharmacol ; 222: 116115, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38460910

RESUMO

In recent years, extensive research has been conducted on the pathogenesis of sensorineural hearing loss (SNHL). Apoptosis and necrosis have been identified to play important roles in hearing loss, but they cannot account for all hearing loss. Autophagy, a cellular process responsible for cell self-degradation and reutilization, has emerged as a significant factor contributing to hearing loss, particularly in cases of autophagy deficiency. Autophagy plays a crucial role in maintaining cell health by exerting cytoprotective and metabolically homeostatic effects in organisms. Consequently, modulating autophagy levels can profoundly impact the survival, death, and regeneration of cells in the inner ear, including hair cells (HCs) and spiral ganglion neurons (SGNs). Abnormal mitochondrial autophagy has been demonstrated in animal models of SNHL. These findings indicate the profound significance of comprehending autophagy while suggesting that our perspective on this cellular process holds promise for advancing the treatment of SNHL. Thus, this review aims to clarify the pathogenic mechanisms of SNHL and the role of autophagy in the developmental processes of various cochlear structures, including the greater epithelial ridge (GER), SGNs, and the ribbon synapse. The pathogenic mechanisms of age-related hearing loss (ARHL), also known as presbycusis, and the latest research on autophagy are also discussed. Furthermore, we underscore recent findings on the modulation of autophagy in SNHL induced by ototoxic drugs. Additionally, we suggest further research that might illuminate the complete potential of autophagy in addressing SNHL, ultimately leading to the formulation of pioneering therapeutic strategies and approaches for the treatment of deafness.


Assuntos
Perda Auditiva Neurossensorial , Perda Auditiva , Animais , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/metabolismo , Células Ciliadas Auditivas/metabolismo , Perda Auditiva/metabolismo , Modelos Animais de Doenças , Autofagia
3.
Biochem Pharmacol ; 213: 115579, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37589048

RESUMO

With the continuous progress of atherosclerosis research, the significant pathological change of it--vascular calcification (VC), gains increasing attention. In recent years, numerous studies have demonstrated that it is an independent predictor of death risk of cardiovascular disease, and it has a strong correlation with poor clinical prognosis. As the world's population continues to age, the occurrence of VC is expected to reach its highest point in the near future. Therefore, it is essential to investigate ways to prevent or even reverse this process for clinical purposes. Endothelial-to-mesenchymal transition (EndMT) describes the progressive differentiation of endothelial cells into mesenchymal stem cells (MSCs) under various stimuli and acquisition of pluripotent cell characteristics. More and more studies show that EndMT plays a vital role in various cardiovascular diseases, including atherosclerosis, vascular calcification and heart valvular disease. EndMT is also involved in the formation and progression of VC. This review vividly describes the history, characteristics of EndMT and how it affects the endothelial cell process, then focuses on the relationship between vascular endothelium, EndMT, amino acid metabolism, and vascular calcification. Finally, it overviews the signal pathway of EndMT and drugs targeting EndMT, hoping to provide new ideas and a theoretical basis for studying potential therapeutic targets of VC.


Assuntos
Aterosclerose , Doenças Cardiovasculares , Calcificação Vascular , Humanos , Células Endoteliais , Endotélio Vascular
4.
ACS Appl Mater Interfaces ; 13(4): 5357-5367, 2021 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-33471500

RESUMO

Herein, the hydrophobic carboxyl-functionalized ionic liquid (IL-COOH) was encapsulated into the prepared Fe3O4@Zr-MOFs, and the novel water-stable IL-COOH/Fe3O4@Zr-MOF nanocomposites were first synthesized. The polydopamine-functionalized Fe3O4 was introduced to construct the core-shell structure via layer-by-layer modification, and the controlled growth of Zr-MOFs was achieved, which realized the adjustment of charged properties of nanocomposites and simplified the adsorption or extraction process. The IL-COOH/Fe3O4@Zr-MOFs were fully studied by IR, HNMR, XRD, N2 adsorption-desorption isotherms, TEM, EDS mapping, VSM, and so on. Then, they were employed for the selective adsorption and detection of fluoroquinolone antibiotics (FQs). The adsorption isotherms and kinetics demonstrated that the adsorption process followed a pseudo-second-order kinetic model and the Langmuir isotherm model. Among them, IL-COOH/Fe3O4@UiO-67-bpydc showed the best adsorption performance, and the maximum adsorption capacity of ofloxacin was 438.5 mg g-1. Coupled magnetic solid-phase extraction with HPLC-DAD, a convenient, sensitive, and efficient method for extraction and detection of FQs in environmental water, was developed based on IL-COOH/Fe3O4@UiO-67-bpydc. The recoveries of environmental water were ranging from 90.0 to 110.0%, and the detection limits were lower than 0.02 µg L-1. The novel functionalized composites served as solid-phase adsorbents and liquid-phase extractants. This study also provided a promising strategy for designing and preparing multi-functionalized nanocomposites for the removal or detection of pollutants in environmental samples.


Assuntos
Antibacterianos/análise , Fluoroquinolonas/análise , Líquidos Iônicos/química , Estruturas Metalorgânicas/química , Nanocompostos/química , Poluentes Químicos da Água/análise , Adsorção , Antibacterianos/isolamento & purificação , Cromatografia Líquida de Alta Pressão/métodos , Fluoroquinolonas/isolamento & purificação , Limite de Detecção , Nanopartículas de Magnetita/química , Extração em Fase Sólida/métodos , Água/análise , Poluentes Químicos da Água/isolamento & purificação
5.
ACS Appl Bio Mater ; 3(11): 7965-7973, 2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-35019536

RESUMO

Nowadays, the environmental risk factors for Alzheimer's disease (AD) have received widespread attention. Two major amyloid-ß peptide (Aß) variants, Aß42 and Aß40, play a pivotal role in the etiology of AD and the concentration ratio of which (i.e., Aß42%) has been suggested to be the superior biomarker for AD. In this study, an "aggregation-based colorimetric sensor array" for the simultaneous identification and detection of Aß40 and Aß42 with structural similarity was established based on gelsolin-modified silver nanotriangles (Ag NTs) and silver nanorods (Ag NRs). Different aggregation behaviors of gelsolin-modified Ag NTs and Ag NRs in the presence of Aß42 and Aß40 resulted in different color and spectral changes, which could be quantitatively analyzed in terms of unique spectral patterns by principal component analysis. With the colorimetric sensor array employed here, the fluctuation of Aß42% in different brain regions of rats exposed to Cd2+ could be directly monitored. The downward trend of Aß42% accompanied by variations of other biochemical indicators suggested that subchronic Cd2+ exposure possibly triggered the onset of AD through the intervention of lipid peroxidation pathway. Furthermore, in vivo monitoring the downtrend of Aß42% in cerebrospinal fluid (CSF) could also be realized, which offers a great opportunity for early diagnosis and treatment of AD that may be induced by environmental factors with CSF Aß42% as a reliable indicator.

6.
Anal Chim Acta ; 1133: 88-98, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-32993877

RESUMO

Sulfonamides antibiotic residues are commonly found in environmental samples, which is highly concerning for public safety and environmental protection. The detection of sulfonamides antibiotics (SAs) is quite important but challenging. In this work, functionalized Zr metal-organic frameworks (Zr-MOFs) and imidazole-based ionic liquids (ILs) were selected and designed according to the structures and properties of SAs. By supporting functionalized ILs into the water-stable Zr-MOFs, the novel ILs@Zr-MOFs nanocomposites were synthesized for the pretreatment of SAs. [H2Nmim][NTf2]@UiO-66-Br showed good selectivity for SAs with maximum adsorption capacity of 352.1 mg g-1 for sulfadiazine. The satisfied performance attributed to not only the large BET surface areas, but also the multiple interactions between the adsorbent and SAs, including electrostatic interaction, hydrogen bonding interaction and π-π interaction. The as-prepared nanocomposites were applied to the dispersive solid phase extraction of SAs in environmental water samples. Combined with high performance liquid chromatography-diode array detector (HPLC-DAD), the effective extraction and sensitive analysis of SAs was achieved by [H2Nmim][NTf2]@UiO-66-Br with enrichment factors higher than 270 and extraction recoveries between 90.5% and 101.9% in short extraction time (10 min). The detection limits were lower than 0.03 µg L-1.


Assuntos
Antibacterianos , Líquidos Iônicos , Estruturas Metalorgânicas , Sulfonamidas , Cromatografia Líquida de Alta Pressão , Extração em Fase Sólida , Água
7.
Anal Chim Acta ; 1105: 147-154, 2020 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-32138913

RESUMO

Herein, a novel ratiometric fluorescent probe based on CDs@Eu/GMP ICP nanoparticles was developed for the detection of Aß monomer in rat as a biomarker for Alzheimer's disease (AD) by fully exploring the competitive coordination interaction and by taking advantage of excellent optical property of carbon dots sensitized lanthanide infinite coordination polymer (ICP) nanoparticles. The carbon dots (CDs) with abundant functional groups were encapsulated into Eu/GMP ICPs through self-adaptive chemistry, which could not only sensitize the red fluorescence of Eu/GMP ICPs effectively, but also act as an internal reference for self-correction. In the absence of Cu2+, the as-formed CDs@Eu/GMP ICPs exhibited the characteristic emission of CDs at 400 nm and strong emission of Eu3+ at 592 nm, 615 nm, 650 nm and 694 nm. With the addition of Cu2+, the red fluorescence of Eu3+ decreased due to the coordination interaction between CDs and Cu2+, thus destroyed the antenna effect. After the subsequent addition of Aß monomer, the specific binding occurred between Cu2+ and Aß monomer, and then the red fluorescence of Eu3+ restored again. During this process, the fluorescence of CDs remained unchanged, thus could be used as an internal reference to cancel out the environmental fluctuation and was more adaptive for the detection of Aß monomer in biological fluids. The method demonstrated here was highly sensitive, free from the interference of other species in rat brain, the in vivo analysis of Aß monomer in CSF and different brain regions from normal rats and Alzheimer's rats could be realized, which was of great significance for better understanding the mechanism of AD and paving the way to understand the chemical essence involved in AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/análise , Encéfalo/diagnóstico por imagem , Corantes Fluorescentes/química , Nanopartículas/química , Animais , Biomarcadores/análise , Carbono/química , Elementos da Série dos Lantanídeos/química , Tamanho da Partícula , Polímeros/química , Pontos Quânticos/química , Ratos , Espectrometria de Fluorescência , Propriedades de Superfície
8.
Environ Pollut ; 224: 436-444, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28258856

RESUMO

In this study, we demonstrated an assay with turn-on fluorescence for monitoring cerebrospinal acetylcholinesterase (AChE) fluctuation as a biomarker for organophosphorus pesticides (OPs) poisoning and management based on single layer MnO2 nanosheets with graphene quantum dots (GQDs) as signal readout. Initially, the fluorescence of GQDs was quenched by MnO2 nanosheets mainly due to the inner filter effect (IFE). However, with the presence of reductive thiocholine (TCh), the enzymatic product, hydrolyzed from acetylthiocholine (ATCh) by AChE, the redox reaction between MnO2 and TCh occurred, leading to the destruction of the MnO2 nanosheets, and thereby IFE was diminished gradually. As a consequence, the turn-on fluorescence of GQDs with the changes in the spectrum of the dispersion constituted a new mechanism for sensing of cerebrospinal AChE. With the method developed here, we could monitor cerebrospinal AChE fluctuation of rats exposed to OPs before and after therapy, and could thereby open up the pathway to a new sensing platform for better understanding the mechanism of brain dysfunctions associate with OPs poisoning.


Assuntos
Acetilcolinesterase/líquido cefalorraquidiano , Grafite/química , Compostos de Manganês/química , Intoxicação por Organofosfatos/líquido cefalorraquidiano , Óxidos/química , Pontos Quânticos/química , Animais , Bioensaio , Biomarcadores/líquido cefalorraquidiano , Masculino , Nanoconchas/química , Intoxicação por Organofosfatos/terapia , Praguicidas/intoxicação , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Espectrometria de Fluorescência/métodos
9.
Sci Rep ; 6: 38417, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27910926

RESUMO

In 2015, more than 30% of erasers were found to contain a PAE content that exceeded the 0.1% limit established by the Quality and Technology Supervision Bureau of Jiangsu Province in China. Thus, strengthening the supervision and regulation of the PAE content in foods and supplies, in particular, remains necessary. Graphene oxide (GO) and its composites have drawn great interests as promising adsorbents for polar and nonpolar compounds. However, GO-based adsorbents are typically restricted by the difficult separation after treatment because of the high pressure in filtration and low density in centrifugation. Herein, a series of novel ionic liquids modified graphene oxide composites (GO-ILs) were prepared as adsorbents for phthalates (PAEs) in eraser samples, which overcame the conventional drawbacks. These novel composites have a combination of the high surface area of graphene oxide and the tunability of the ionic liquids. It is expected that the GO-ILs composites can be used as efficient adsorbents for PAEs from aqueous solution. This work also demonstrated a new technique for GO-based materials applied in sample preparation.

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