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1.
Nano Lett ; 24(42): 13333-13340, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39361829

RESUMO

Chiral microlasers hold great promise for optoelectronics from integrated photonic devices to high-density quantum information processing. Despite significant progress in lead-halide perovskite emitters, chiral lasing with high dissymmetry factors (glum) has not yet been realized. Here, we demonstrate chiral single-mode microlasers with exceptional stability and tunable emission across the visible range by combining CsPbClxBr3-x perovskite microrods (MRs) with a cholesteric liquid crystal (CLC) layer. The MRs lase via a whispering gallery mode (WGM) microcavity and confer chirality through the encapsulated CLC layer, thus exhibiting circularly polarized lasing with dissymmetry factors reaching 1.62. Importantly, we demonstrate wavelength-tunable high dissymmetry chiral lasers in a broad spectral range by tuning the halide composition and using CLC layers with the desired photonic bandgap (PBG). This facile approach to generate chiral lasing not only is applicable to semiconductor nano- and microcrystals but also paves the way for potential integration into nanoscale photonic devices.

2.
J Cell Mol Med ; 28(20): e70106, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39422584

RESUMO

The expression of the long noncoding RNA (lncRNA) TPTE pseudogene 1 (TPTEP1) is significantly downregulated in ovarian cancer (OC). However, the function and mechanism of the lncRNA TPTEP1 in OC have not been identified. To investigate the expression of the lncRNA TPTEP1, we analysed a publicly available dataset and 20 pairs of OC and normal ovarian samples tissue from the First Affiliated Hospital of Anhui Medical University. Functional assays were used to determine the role of the lncRNA TPTEP1 in OC progression. Furthermore, Western blot, FISH, RNA pull-down, mass spectrometry and RNA immunoprecipitation approaches were used to determine the mechanism by which the lncRNA TPTEP1 affects OC progression. Animal experiments were used to determine the role of the lncRNA TPTEP1 in ovarian tumorigenicity in vivo. The expression of the lncRNA TPTEP1 in OC tissues was significantly lower than that in normal tissues and low expression of the lncRNA TPTEP1 was significantly correlated with advanced FIGO stage and the presence of malignant ascites in OC patients. In vitro and in vivo, regulation of the expression of the lncRNA TPTEP1 caused changes in OC cell proliferation, migration, invasion and apoptosis. Mechanistically, we found that TPTEP1 directly binds to the polypyrimidine tract-binding protein 1 (PTBP1) protein and inhibits PI3K/AKT signalling. The lncRNA TPTEP1 inhibits PI3K/AKT signalling by directly binding PTBP1, possibly indicating the molecular mechanism underlying its biological function. With further research, these findings may aid in the development of clinically useful strategies for the treatment of OC.


Assuntos
Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Ribonucleoproteínas Nucleares Heterogêneas , Neoplasias Ovarianas , Fosfatidilinositol 3-Quinases , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Proteínas Proto-Oncogênicas c-akt , RNA Longo não Codificante , Transdução de Sinais , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Feminino , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Fosfatidilinositol 3-Quinases/metabolismo , Animais , Proliferação de Células/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Camundongos , Progressão da Doença , Camundongos Nus , Apoptose/genética , Pessoa de Meia-Idade
3.
Small ; 20(12): e2306991, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939298

RESUMO

The shuttle effect, which causes the loss of active sulfur, passivation of lithium anode, and leads to severe capacity attenuation, is currently the main bottleneck for lithium-sulfur batteries. Recent studies have disclosed that molybdenum compounds possess exceptional advantages as a polar substrate to immobilize and catalyze lithium polysulfide such as high conductivity and strong sulfiphilicity. However, these materials show incomplete contact with sulfur/polysulfides, which causes uneven redox conversion of sulfur and results in poor rate performance. Herein, a new type of 2D nano-channeled molybdenum compounds (2D-MoNx) via the 2D organic-polyoxometalate superstructure for accelerating interfacial polysulfide catalysis toward high-performance lithium-sulfur batteries is reported. The 2D-MoNx shows well-interlinked nano-channels, which increase the reactive interface and contact surface with polysulfides. Therefore, the battery equipped with 2D-MoNx displays a high discharge capacity of 912.7 mAh g-1 at 1 C and the highest capacity retention of 523.7 mAh g-1 after 300 cycles. Even at the rate of 2 C, the capacity retention can be maintained at 526.6 mAh g-1 after 300 cycles. This innovative nano-channel and interfacial design of 2D-MoNx provides new nanostructures to optimize the sulfur redox chemistry and eliminate the shuttle effect of polysulfides.

4.
Mol Psychiatry ; 28(5): 2107-2121, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36754983

RESUMO

Psychosis is an abnormal mental condition that can cause patients to lose contact with reality. It is a common symptom of schizophrenia, bipolar disorder, sleep deprivation, and other mental disorders. Clinically, antipsychotic medications, such as olanzapine and clozapine, are very effective in treatment for psychosis. To investigate the neural circuit mechanism that is affected by antipsychotics and identify more selective therapeutic targets, we employed a strategy by using these effective antipsychotics to identify antipsychotic neural substrates. We observed that local injection of antipsychotics into the ventral tegmental area (VTA) could reverse the sensorimotor gating defects induced by MK-801 injection in mice. Using in vivo fiber photometry, electrophysiological techniques, and chemogenetics, we found that antipsychotics could activate VTA gamma-aminobutyric acid (GABA) neurons by blocking GABAA receptors. Moreover, we found that the VTAGABA nucleus accumbens (NAc) projection was crucially involved in such antipsychotic effects. In summary, our study identifies a novel therapeutic target for the treatment of psychosis and underscores the utility of a 'bedside-to-bench' approach for identifying neural circuits that influence psychotic disorders.

5.
Am J Obstet Gynecol ; 2024 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-39426783

RESUMO

BACKGROUND: Pelvic magnetic resonance imaging has been proven effective for quantifying the extent of prolapse. The pubococcygeal line is used universally as a reference line in measuring pelvic organ prolapse, however, it focuses solely on three lowest points in the anterior, middle, and posterior pelvic compartments, without taking into account other pelvic floor structures and their interactions. OBJECTIVES: This study aimed to introduce and validate the area under the pubococcygeal line, a novel measurement method for evaluating pelvic organ prolapse, to examine its correlation with clinical Pelvic Organ Prolapse Quantification staging, and assess its reliability across different raters. STUDY DESIGN: This study recruited 225 women who underwent evaluations involving both magnetic resonance imaging measurements and clinical Pelvic Organ Prolapse Quantification staging. A comprehensive statistical approach involving descriptive analysis, correlation analysis, reliability assessment, and ordinal logistic regression analysis was adopted to evaluate the applicability and reliability of the area under the pubococcygeal line measurement. RESULTS: Analysis of participant characteristics across different POP-Q stages revealed a significant association between increased values of the area under the pubococcygeal line and severity of Pelvic Organ Prolapse Quantification staging. Correlation analysis was performed to identify and quantify the strength of the associations between the variables. The area under the pubococcygeal line showed a strong positive correlation with Pelvic Organ Prolapse Quantification stages (Spearman's r = 0.878, p < 0.001), outperforming the pubococcygeal line grades (Spearman's r = 0.777, p < 0.001). Reliability assessments yielded excellent intra- and inter-rater reliability, with intraclass correlation coefficient values of 0.980 and 0.906, respectively. Ordinal logistic regression analysis was used to determine the association between these variables and POP severity, highlighting significant associations between the area under the pubococcygeal line and Pelvic Organ Prolapse Quantification stages. CONCLUSION: The area under the pubococcygeal line measurement method is a novel and comprehensive magnetic resonance imaging technique for evaluating pelvic organ prolapse. This method strongly correlates with clinical Pelvic Organ Prolapse Quantification stages and exhibits excellent intra- and inter-rater reliability, holding a potential for enhanced diagnostic accuracy, optimized treatment strategies, and improved patient outcomes.

6.
Int J Mol Sci ; 25(11)2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38892414

RESUMO

Berberine (BBR) is used to treat cancer, inflammatory conditions, and so on. But the side effects of BBR causing constipation should not be ignored. In clinical application, the combination of Amomum villosum Lour. (AVL) and BBR can relieve it. However, the effective ingredients and molecular mechanism of AVL in relieving constipation are not clear. A small intestine propulsion experiment was conducted in constipated mice to screen active ingredients of AVL. We further confirmed the molecular mechanism of action of the active ingredient on BBR-induced constipation. Quercetin (QR) was found to be the effective ingredient of AVL in terms of relieving constipation. QR can efficiently regulate the microbiota in mice suffering from constipation. Moreover, QR significantly raised the levels of substance P and motilin while lowering those of 5-hydroxytryptamine and vasoactive intestinal peptide; furthermore, it also increased the protein expression levels of calmodulin, myosin light-chain kinase, and myosin light chain. The use of QR in combination with BBR has an adverse effect-reducing efficacy. The study provides new ideas and possibilities for the treatment of constipation induced by BBR.


Assuntos
Berberina , Constipação Intestinal , Microbioma Gastrointestinal , Quercetina , Animais , Berberina/farmacologia , Berberina/uso terapêutico , Quercetina/farmacologia , Constipação Intestinal/tratamento farmacológico , Constipação Intestinal/induzido quimicamente , Microbioma Gastrointestinal/efeitos dos fármacos , Camundongos , Masculino , Modelos Animais de Doenças , Motilina/metabolismo
7.
Entropy (Basel) ; 26(3)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38539751

RESUMO

Efficient flotation beneficiation heavily relies on accurate flotation condition recognition based on monitored froth video. However, the recognition accuracy is hindered by limitations of extracting temporal features from froth videos and establishing correlations between complex multi-modal high-order data. To address the difficulties of inadequate temporal feature extraction, inaccurate online condition detection, and inefficient flotation process operation, this paper proposes a novel flotation condition recognition method named the multi-modal temporal hypergraph neural network (MTHGNN) to extract and fuse multi-modal temporal features. To extract abundant dynamic texture features from froth images, the MTHGNN employs an enhanced version of the local binary pattern algorithm from three orthogonal planes (LBP-TOP) and incorporates additional features from the three-dimensional space as supplements. Furthermore, a novel multi-view temporal feature aggregation network (MVResNet) is introduced to extract temporal aggregation features from the froth image sequence. By constructing a temporal multi-modal hypergraph neural network, we encode complex high-order temporal features, establish robust associations between data structures, and flexibly model the features of froth image sequence, thus enabling accurate flotation condition identification through the fusion of multi-modal temporal features. The experimental results validate the effectiveness of the proposed method for flotation condition recognition, providing a foundation for optimizing flotation operations.

8.
Artigo em Inglês | MEDLINE | ID: mdl-37963065

RESUMO

OBJECTIVE: To investigate the pathogenic role and underlying mechanisms of lncRNAs in antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). METHODS:: RNA-sequencing (RNA-seq) was applied to screen the expression profile of lncRNAs in peripheral leukocytes from 5 AAV patients and 5 healthy controls (HC). Candidate lncRNAs were preliminarily verified in peripheral leukocytes from 46 AAV patients and 35 HC by qRT-PCR. Then, the identified LINC02193 was further validated in peripheral neutrophils from 67 AAV patients, 45 HC and 64 disease controls. Correlation between LINC02193 levels and disease activity was analyzed. Then, a loss-of-function study was conducted to investigate the role of LINC02193 in neutrophils activation. Furthermore, bioinformatics analysis, dual luciferase reporter and RNA immunoprecipitation (RIP) assays were performed to explore the mechanism of LINC02193 regulating neutrophils activation. RESULTS: A total of 467 upregulated and 412 downregulated lncRNAs were identified in AAV patients. From top 5 upregulated lncRNAs, an elevation of LINC02193 was validated in a larger sample of AAV patients, and positively correlated with disease activity. Knockdown of LINC02193 inhibited ROS and NO production, NETs release and adhesion to endothelial cells of differentiated human promyelocytic leukaemia HL­60 cells (dHL-60), whereas overexpression of ICAM1 counteracted these effects. Mechanistic analysis demonstrated that LINC02193 acted as a miR-485-5p sponge to relieve the repressive effect of miR-485-5p on ICAM1, thus promoting ICAM1 expression. CONCLUSION: LINC02193, a novel lncRNA identified in AAV could function as competing endogenous RNAs (ceRNA) for miR-485-5p to promote ICAM1 expression and neutrophils activation, suggesting its potential as a therapeutic target of AAV.

9.
Opt Express ; 31(25): 42240-42254, 2023 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-38087602

RESUMO

Non-line-of-sight (NLOS) imaging can visualize a remote object out of the direct line of sight and can potentially be used in endoscopy, unmanned vehicles, and robotic vision. In an NLOS imaging system, multiple diffusive reflections of light usually induce large optical attenuation, and therefore, a sensitive and efficient photodetector, or, their array, is required. Limited by the spectral sensitivity of the light sensors, up to now, most of the NLOS imaging experiments are performed in the visible bands, and a few at the near-infrared, 1550 nm. Here, to break this spectral limitation, we demonstrate a proof-of-principle NLOS imaging system using a fractal superconducting nanowire single-photon detector, which exhibits intrinsic single-photon sensitivity over an ultra-broad spectral range. We showcase NLOS imaging at 1560- and 1997-nm two wavelengths, both technologically important for specific applications. We develop a de-noising algorithm and combine it with the light-cone-transform algorithm to reconstruct the shape of the hidden objects with significantly enhanced signal-to-noise ratios. We believe that the joint advancement of the hardware and the algorithm presented in this paper could further expand the application spaces of the NLOS imaging systems.

10.
Opt Lett ; 48(2): 415-418, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638471

RESUMO

We demonstrate a fiber-coupled fractal superconducting nanowire single-photon detector (SNSPD) system with minimum polarization dependence of detection efficiency. Its system detection efficiency (SDE) was maximized at the wavelength of 1540 nm, which was measured to be 91 ± 4%; furthermore, we observed the second local maximum of SDE at the wavelength of 520 nm, which was measured to be 61 ± 2%. This dual-band feature of SDE was due to the enhancement of the optical absorptance by two longitudinal resonance modes of the micro-cavity. By using high SDE with minimum polarization dependence in these two bands, we implemented a hybrid LIDAR for imaging the remote objects in free space and under water.

11.
Exp Cell Res ; 417(2): 113221, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35623419

RESUMO

Subretinal fibrosis causes local damage to the retina and irreversible vision loss, as the final stage of neovascular age-related macular degeneration (nAMD). More recently, the endothelial-to-mesenchymal transition (EndoMT) has been considered one of the most significant sources of myofibroblasts in subretinal fibrosis, though the underpinning molecular mechanisms remain unclear. In this study, a series of experiments were performed to test the hypothesis that Yes-associated protein (YAP) may be involved in EndoMT and subretinal fibrosis. We demonstrated that transforming growth factor (TGF)-ß2 stimulation induces YAP dephosphorylation (activated) and nuclear transcription in human umbilical vein endothelial cells (HUVECs) by increasing reactive oxygen species (ROS) levels. Moreover, TGF-ß2-mediated EndoMT and proinflammatory cytokine production in HUVECs were reduced by ROS clearance or YAP knockdown. Furthermore, the severity of subretinal fibrosis was markedly relieved by intravitreal administration of a small interfering RNA targeting YAP in the mouse laser-induced choroidal neovascularization (CNV) model. Our findings provide novel insights into a previously unknown effect of YAP on the EndoMT process and reveal YAP as a potential target for suppressing CNV-related subretinal fibrosis and protect vision.


Assuntos
Neovascularização de Coroide , Animais , Neovascularização de Coroide/genética , Modelos Animais de Doenças , Fibrose , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Inflamação/complicações , Camundongos , Camundongos Endogâmicos C57BL , Espécies Reativas de Oxigênio
12.
Bioorg Chem ; 138: 106594, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37186998

RESUMO

The selective inhibition of PI3Kδ is a potential therapeutic strategy for the treatment of hematologic malignancies. Herein, we report a series of compounds bearing amino acid fragments as potent and selective PI3Kδ inhibitors. Among them, compound A10 exhibited sub-nanomolar PI3Kδ potency. In cellular assays, A10 achieved strong antiproliferation against SU-DHL-6 cells, and caused cell cycle arrest, and induced apoptosis in SU-DHL-6 cells. The docking study showed that A10 tightly bound to PI3Kδ protein with a planar-shaped conformation. Collectively, compound A10 represented a promising potent and selective PI3Kδ inhibitor bearing amino acid fragement albeit with moderate selectivity over PI3Kγ but superior selectivity against PI3Kα and ß. This study suggested that using the amino acid fragments instead of the pyrrolidine ring is new strategy for design of potent PI3Kδ inhibitors.


Assuntos
Aminoácidos , Inibidores de Proteínas Quinases , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade , Linhagem Celular Tumoral , Aminoácidos/farmacologia , Proliferação de Células
13.
Neoplasma ; 70(2): 216-228, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36964721

RESUMO

Ovarian cancer (OC) is one of the most prevalent malignant tumors affecting women's life and health. Since OC has a poor prognosis due to extensive metastasis, there is a need to explore a new mechanism of OC metastasis. microRNAs (miRs) are single-stranded, non-coding RNAs. miR-9 has been reported to promote cancer and may provide a new strategy for OC diagnosis. The purpose of this study was to examine the function and underlying mechanism of miR-9 in OC. RT-qPCR was used to assess miR-9 expression levels. Transwell assays were used to determine the number of migrating and invading OC cells. The protein expression levels of the PI3K/AKT/mTOR/GSK3ß signaling pathway were examined using western blotting. The results informed that, when compared to normal ovarian tissues, miR-9 was remarkably expressed in OC tissues, and hypoxia might lead to overexpression of miR-9-5p while inhibiting miR-9 notably suppressed the migrating and invading cell numbers in OC cells. In vivo, miR-9-5p knockdown inhibited tumor growth in a subcutaneous nude mice model of SKOV3 cells. Our findings suggest that miR-9 could be an underlying oncogene in OC, opening up new avenues for OC diagnosis and treatment of OC by targeting miR-9.


Assuntos
MicroRNAs , Neoplasias Ovarianas , Humanos , Animais , Camundongos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos Nus , Glicogênio Sintase Quinase 3 beta/metabolismo , Proliferação de Células , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Ovarianas/patologia , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Linhagem Celular Tumoral , Movimento Celular
14.
Ecotoxicol Environ Saf ; 262: 115319, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37542982

RESUMO

Ultraviolet B (UV-B, 280-320 nm) radiation is a major environmental stressor for aquatic organisms on Earth's surface. Its effects on biological systems are well known, but the mechanisms by which organisms respond and adapt to UV-B radiation are still being explored. In this study, we investigated the effects of UV-B radiation on the monogonont rotifer Brachionus asplanchnoidis, focusing on physiological parameters, antioxidant systems, DNA damage, and DNA repair-related molecular mechanism. Our results showed that the LD50 was at 28.53 kJ/m2, indicating strong tolerance to UV-B. However, UV-B radiation caused adverse effects on growth and reproduction, with shortened reproductive period and longevity, decreased fecundity and hatchability, and inhibition of population growth. Biochemical analyses revealed severe oxidative damage and lipid peroxidation, with increased ROS and MDA levels. Activities of antioxidant enzymes were highly induced at low doses but decreased at high doses. DNA damage also occurred in UV-B-exposed rotifers. Furthermore, selected DNA repair-related genes were up-regulated in a dose-dependent manner. These findings provide a comprehensive understanding of the effects of UV-B radiation on rotifers and highlight the importance of considering both ecological and molecular responses in assessing the impact of UV-B radiation on aquatic organisms.

15.
Chem Biodivers ; 20(8): e202300754, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37401658

RESUMO

Magnolol and Honokiol are the primary active components that have been identified and extracted from Magnolia officinalis, and several investigations have demonstrated that they have significant pharmacological effects. Despite their therapeutic benefits for a wide range of illnesses, research on and the implementation of these compounds have been hindered by their poor water solubility and low bioavailability. Researchers are continually using chemical methods to alter their structures to make them more effective in treating and preventing diseases. Researchers are also continuously developing derivative drugs with high efficacy and few adverse effects. This article summarizes and analyzes derivatives with significant biological activities reported in recent research obtained by structural modification. The modification sites have mainly focused on the phenolic hydroxy groups, benzene rings, and diene bonds. Changes to the allyl bisphenol structure will result in unexpected benefits, including high activity, low toxicity, and good bioavailability. Furthermore, alongside earlier experimental research in our laboratory, the structure-activity relationships of magnolol and honokiol were preliminarily summarized, providing experimental evidence for improving their development and utilization.


Assuntos
Lignanas , Magnolia , Lignanas/farmacologia , Lignanas/química , Compostos de Bifenilo/química , Relação Estrutura-Atividade , Magnolia/química
16.
Chem Biodivers ; 20(8): e202300578, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37458474

RESUMO

The rhizoma of Anemarrhenae asphodeloides has a long history of hypoglycemic use in Chinese traditional medicine. In this article, 400 µmol/L H2 O2 induced normal INS-1 pancreatic beta cells to establish experimental model of oxidative damage. Quercetin was used as a positive drug, and mangiferin and its ethanolic extract were selected as therapeutic agents in an oxidative damage model to evaluate the ameliorative effect of the active ingredients of Anemarrhenae asphodeloides rhizoma on oxidative damage in INS-1 pancreatic ß-cells. Building a qualitative analysis method of membrane phospholipids of INS-1 pancreatic beta cells and identified 82 phospholipids based on the UPLC/Q-TOF MS technology, which could provide a database for further statistics analysis. OPLS-DA was used to screen the phospholipid biomarkers from the raw data. Exploring the biological significances of these biomarkers, and discussing the toxic effect of the effective components of Anemarrhena asphodeloides rhizoma, on oxidatively damaged INS-1 pancreatic beta cell.


Assuntos
Anemarrhena , Medicamentos de Ervas Chinesas , Células Secretoras de Insulina , Cromatografia Líquida de Alta Pressão/métodos , Rizoma , Medicamentos de Ervas Chinesas/farmacologia
17.
Mikrochim Acta ; 190(4): 150, 2023 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-36952134

RESUMO

For practical analysis and simultaneous detection of arbutin (AR) and hydrochinone (HQ) in cosmetics, an electrochemical sensor has been designed based on nitrogen and sulfur co-doped Fe-Ni alloy (N,S-FeNi3/C) nanoparticles. The N,S-FeNi3/C has been prepared for the first time via hydrothermal synthesis and high-temperature carbonization. N,S-FeNi3/C not only improves the charge transfer to the surface, but also provides rich active sites and fast ion diffusion rates owing to the iron and nickel bimetallic materials. In addition, the d-band structure of transition metals (nickel and iron) introduced by the N and S atoms exhibits an electronic structure similar to that of noble metal catalysts, thus enhancing electrocatalytic activity and increasing conductivity. Additionally, the double doping of S and N atoms significantly increases the active sites of carbon atoms; thus, N-S-FeNi3/C exhibits excellent electrochemical catalytic activity for the oxidation of AR and HQ. Further, the N,S-FeNi3/C sensor is used for the simultaneous determination of HQ and AR by square-wave pulse voltammetry. Distinct oxidation peaks of HQ and AR are observed at potentials of +0.028 V and +0.352 V (vs. SCE). The electrical signal increases linearly in the HQ concentration ranges of 0.1-100 µM and 0.05-70 µM for the simultaneous determination of AR and HQ with a detection limit as low as 0.0476 and 0.0135 µM (S/N = 3), respectively. Thus, rapid and accurate detection of AR and HQ in spiked cosmetics is successfully achieved, with a recovery ranging from 96.4 to 104.2%, and the relative standard deviation is lower than 3.8-4.0%.

18.
Int J Mol Sci ; 24(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446006

RESUMO

The pathogenesis of ulcerative colitis (UC) is associated with inflammation, oxidative stress, and gut microbiota imbalance. Although most researchers have demonstrated the antioxidant bioactivity of the phenolic compounds in plants, their UC-curing ability and underlying mechanisms still need to be further and adequately explored. Herein, we studied the antioxidation-structure relationship of several common polyphenols in plants including gallic acid, proanthocyanidin, ellagic acid, and tannic acid. Furthermore, the in vivo effects of the plant polyphenols on C57BL/6 mice with dextran-sulfate-sodium-induced UC were evaluated and the action mechanisms were explored. Moreover, the interplay of several mechanisms was determined. The higher the number of phenolic hydroxyl groups, the stronger the antioxidant activity. All polyphenols markedly ameliorated the symptoms and pathological progression of UC in mice. Furthermore, inflammatory cytokine levels were decreased and the intestinal barrier was repaired. The process was regulated by the antioxidant-signaling pathway of nuclear-erythroid 2-related factor 2. Moreover, the diversity of the intestinal microbiota, Firmicutes-to-Bacteroides ratio, and relative abundance of beneficial bacteria were increased. An interplay was observed between microbiota regulation and oxidative stress, immunity, and inflammatory response. Furthermore, intestinal barrier repair was found to be correlated with inflammatory responses. Our study results can form a basis for comprehensively developing plant-polyphenol-related medicinal products.


Assuntos
Colite Ulcerativa , Microbiota , Animais , Camundongos , Camundongos Endogâmicos C57BL , Antioxidantes/farmacologia , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Colite Ulcerativa/induzido quimicamente , Colite Ulcerativa/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Fenóis
19.
Molecules ; 28(9)2023 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-37175163

RESUMO

Based on the principle of molecular splicing and theory of traditional Chinese medicine pairs, a new multi-active compound (HM475) was synthesized by connecting metformin with honokiol, and its structure was characterized, which not only reduced the toxicity of raw materials, but also maintained the original activity, and had a certain significance in research and innovation. At the same time, quality control and preliminary activity evaluation were carried out, and the effect of HM475 on neuroinflammation was further explored, which provided a new idea for drug development of neurodegenerative diseases.


Assuntos
Medicamentos de Ervas Chinesas , Lignanas , Medicina Tradicional Chinesa , Controle de Qualidade , Compostos de Bifenilo , Desenvolvimento de Medicamentos , Lignanas/farmacologia
20.
Int Ophthalmol ; 43(10): 3831-3839, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37561250

RESUMO

PURPOSE: To investigate the neuroprotective effect of idebenone against hydrogen peroxide (H2O2)-induced oxidative damage in retinal ganglion cells-5 (RGC-5 cells). METHODS: RGC-5 cells were pre-treated with various idebenone concentrations (5, 10, and 20 µM) for 12 h and were then subjected to 300 µM H2O2 for a further 12 h. Apoptosis in RGC-5 was measured by flow cytometry. The changes of mitochondrial membrane potential (MMP) were detected by JC-1 staining. Autophagy in RGC-5 cells was observed by transmission electron microscopy. Western blots were used to measure the expression of autophagy-related protein light chain 3 (LC3), Beclin-1, and the release of Cytochrome c (Cyt-c). RESULTS: Flow cytometry showed that the apoptosis rates in the normal control group, H2O2 group, and idebenone groups were 6.48 ± 0.55%, 27.3 ± 0.51%, 22.8 ± 0.52%, 15.45 ± 0.81%, and 12.59 ± 0.58%, respectively (F = 559.7, P < 0.0001). After incubation with H2O2, the number of autophagosomes increased significantly, whereas it was decreased in the idebenone groups. After incubation of RGC-5 cells with H2O2, MMP levels were significantly decreased, while idebenone could prevent the decrease in MMP levels. Compared with that in the normal control group, LC3 II/I, the expression levels of Beclin-1 and Cyt-c were increased significantly in the H2O2 group (P < 0.05). Compared with that in the H2O2 group, LC3 II/I, the expression of Beclin-1 and Cyt-c was significantly decreased in idebenone groups (P < 0.05). CONCLUSIONS: Idebenone protects RGC-5 cells against H2O2-induced oxidative damage by reducing mitochondrial damage and autophagic activity.


Assuntos
Fármacos Neuroprotetores , Humanos , Fármacos Neuroprotetores/farmacologia , Peróxido de Hidrogênio/toxicidade , Peróxido de Hidrogênio/metabolismo , Proteína Beclina-1/farmacologia , Células Ganglionares da Retina , Estresse Oxidativo , Sobrevivência Celular
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