RESUMO
The 3,3',5,5'-tetramethylbenzidine-H2O2 (TMB-H2O2) platform has gained widespread use for rapid detection of various analytes in foods. However, the existing TMB-H2O2 platforms suffer from limited accuracy, as their signal output is confined to the visible region, which is prone to interference from various food colorants in real samples. To address this challenge, a novel Au@Os-mediated TMB-H2O2 platform is developed for both rapid and accurate detection of analytes in foods. The prepared Au@Os NPs exhibit remarkable peroxidase-like activity, making the platform display dual absorption peaks in visible and near-infrared (NIR) regions, respectively. This Au@Os-mediated TMB-H2O2 platform exhibited three linear ranges across different concentrations of ziram from 1-100, 150-600, and 800-2000 nM with limit of detection (LOD) 7.9 nM and limit of quantification (LOQ) 24.15 nM respectively. Further, the Au@Os-mediated TMB-H2O2 platform was also used for rapid and accurate detection of ziram in real food samples like apple, tomato, and black tea.
Assuntos
Contaminação de Alimentos , Ouro , Peróxido de Hidrogênio , Limite de Detecção , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Ouro/química , Contaminação de Alimentos/análise , Benzidinas/química , Malus/química , Solanum lycopersicum/química , Chá/química , Nanopartículas Metálicas/química , Corantes de Alimentos/análiseRESUMO
Numerous nanoparticles have been utilized to deliver Fe2+ for tumor ferroptosis therapy, which can be readily converted to Fe3+via Fenton reactions to generate hydroxyl radical (â¢OH). However, the ferroptosis therapeutic efficacy of large tumors is limited due to the slow conversion of Fe3+ to Fe2+via Fenton reactions. Herein, a strategy of intratumor Fe3+/2+ cyclic catalysis is proposed for ferroptosis therapy of large tumors, which was realized based on our newly developed hollow mesoporous iron sesquioxide nanoparticle (HMISN). Cisplatin (CDDP) and Gd-poly(acrylic acid) macrochelates (GP) were loaded into the hollow core of HMISN, whose surface was modified by laccase (LAC). Fe3+, CDDP, GP, and LAC can be gradually released from CDDP@GP@HMISN@LAC in the acidic tumor microenvironment. The intratumor O2 can be catalyzed into superoxide anion (O2â¢-) by LAC, and the intratumor NADPH oxidases can be activated by CDDP to generate O2â¢-. The O2â¢- can react with Fe3+ to generate Fe2+, and raise H2O2 level via the superoxide dismutase. The generated Fe2+ and H2O2 can be fast converted into Fe3+ and â¢OH via Fenton reactions. The cyclic catalysis of intratumor Fe3+/2+ initiated by CDDP@GP@HMISN@LAC can be used for ferroptosis therapy of large tumors.
Assuntos
Ferroptose , Ferro , Ferroptose/efeitos dos fármacos , Animais , Catálise , Humanos , Ferro/química , Linhagem Celular Tumoral , Nanopartículas/química , Porosidade , Camundongos , Cisplatino/química , Cisplatino/uso terapêutico , Neoplasias/tratamento farmacológico , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Camundongos Endogâmicos BALB C , Peróxido de Hidrogênio/química , Microambiente Tumoral/efeitos dos fármacos , Camundongos Nus , FemininoRESUMO
Osteomyelitis is an osseous infectious disease that primarily affects children and the elderly with high morbidity and recurrence. The conventional treatments of osteomyelitis contain long-term and high-dose systemic antibiotics with debridements, which are not effective and lead to antibiotic resistance with serious side/adverse effects in many cases. Hence, developing novel antibiotic-free interventions against osteomyelitis (especially antibiotic-resistant bacterial infection) is urgent and anticipated. Here, a bone mesenchymal stem cell membrane-constructed nanocell (CFE@CM) was fabricated against osteomyelitis with the characteristics of acid-responsiveness, hydrogen peroxide self-supplying, enhanced chemodynamic therapeutic efficacy, bone marrow targeting and cuproptosis induction. Notably, mRNA sequencing was applied to unveil the underlying biological mechanisms and found that the biological processes related to copper ion binding, oxidative phosphorylation, peptide biosynthesis and metabolism, etc., were disturbed by CFE@CM in bacteria. This work provided an innovative antibiotic-free strategy against osteomyelitis through copper-enhanced Fenton reaction and distinct cuproptosis, promising to complement the current insufficient therapeutic regimen in clinic.
Assuntos
Cobre , Osteomielite , Osteomielite/tratamento farmacológico , Animais , Cobre/química , Cobre/farmacologia , Concentração de Íons de Hidrogênio , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Camundongos , Peróxido de Hidrogênio/metabolismo , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antibacterianos/química , Humanos , Staphylococcus aureus/efeitos dos fármacosRESUMO
Low fluorescence under visible light excitation and catalytic activity limit many applications of graphene quantum dots in optical detection, biosensing, catalysis and biomedical. The paper reports design and synthesis of histidine, serine and folic acid-functionalized and boron and iron-doped graphene quantum dot (Fe/B-GQD-HSF). The Fe/B-GQD-HSF shows excellent fluorescence behavior and peroxidase-like activity. Excitation of 330 nm ultraviolet light produces the strongest blue fluorescence and excitation of 480 nm visible light produces the strongest yellow fluorescence. The specific activity reaches 92.67 U g-1, which is higher than that of other graphene quantum dots. The Fe/B-GQD-HSF can catalyze oxidation of 3,3',5,5'-tetramethylbenzidine with H2O2 to form blue compound. Based on this, it was used for colorimetric and fluorescence detection of H2O2. The absorbance at 652 nm linearly increases with the increase of H2O2 concentration between 0.5 and 100 µM with detection limit of 0.43 µM. The fluorescence signal linearly decreases with the increase of H2O2 concentration between 0.05 and 100 µM with detection limit of 0.035 µM. The analytical method has been satisfactorily applied in detection of H2O2 in food. The study also paves one way for design and synthesis of functional graphene quantum dots with ideal fluorescence behavior and catalytic activity.
Assuntos
Boro , Colorimetria , Ácido Fólico , Grafite , Histidina , Peróxido de Hidrogênio , Ferro , Pontos Quânticos , Serina , Pontos Quânticos/química , Grafite/química , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/química , Colorimetria/métodos , Ácido Fólico/análise , Ácido Fólico/química , Ferro/análise , Ferro/química , Boro/química , Histidina/análise , Histidina/química , Serina/análise , Serina/química , Espectrometria de Fluorescência/métodos , Limite de Detecção , Análise de Alimentos/métodos , Peroxidase/química , Peroxidase/metabolismo , CatáliseRESUMO
Fenton and Fenton-like processes, which could produce highly reactive species to degrade organic contaminants, have been widely used in the field of wastewater treatment. Therein, the chemistry of Fenton process including the nature of active oxidants, the complicated reactions involved, and the behind reason for its strongly pH-dependent performance, is the basis for the application of Fenton and Fenton-like processes in wastewater treatment. Nevertheless, the conflicting views still exist about the mechanism of the Fenton process. For instance, reaching a unanimous consensus on the nature of active oxidants (hydroxyl radical or tetravalent iron) in this process remains challenging. This review comprehensively examined the mechanism of the Fenton process including the debate on the nature of active oxidants, reactions involved in the Fenton process, and the behind reason for the pH-dependent degradation of contaminants in the Fenton process. Then, we summarized several strategies that promote the Fe(II)/Fe(III) cycle, reduce the competitive consumption of active oxidants by side reactions, and replace the Fenton reagent, thus improving the performance of the Fenton process. Furthermore, advances for the future were proposed including the demand for the high-accuracy identification of active oxidants and taking advantages of the characteristic of target contaminants during the degradation of contaminants by the Fenton process.
Assuntos
Peróxido de Hidrogênio , Ferro , Eliminação de Resíduos Líquidos , Ferro/química , Peróxido de Hidrogênio/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluentes Químicos da Água/análise , Águas Residuárias/química , Oxirredução , Radical Hidroxila/químicaRESUMO
Persulfate (PS) is a widely used oxidant for the chemical oxidation of organic pollutants. The accurate measurement of PS concentration is crucial for the practical application process. The iodometry is the most recommended method for PS determination, and its principle is based on the redox reaction between S2O82- and iodide ions. However, hydrogen peroxide (H2O2), an important intermediate product in the process of PS use, often leads to abnormally high determination concentrations of PS. Given this, a novel method was developed for the determination of PS based on the principle of the oxidation of chloride ion (Cl-). The concentration of PS is calculated according to the consumption of Cl- concentration, which is not disturbed by H2O2. The optimized test conditions were explored as: C(H+) = 2 mol/L, T = 80â, C(Cl-):C(PS) = 4:1 and t = 30 min. Under the optimized conditions, the limit of detection and the limit of quantification of PS concentration determined by this method were 0.26 and 0.85 g/L, respectively. And the linear range of the PS determination was 1-100 g/L with an error of 0.53%-12.06%. The spike recovery rate for determining PS concentration in the actual wastewater ranged from 94.07%-109.52%. Interfering factors such as H2O2, Fe3+, MnO2 and natural organic matter had almost no effect on the results. This method could not only accurately determine the concentration of PS in industrial wastewater, but also determine the purity of PS industrial products.
Assuntos
Cloretos , Peróxido de Hidrogênio , Oxirredução , Sulfatos , Poluentes Químicos da Água , Sulfatos/análise , Sulfatos/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Cloretos/análise , Cloretos/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Águas Residuárias/químicaRESUMO
Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal fibrotic lung disease. While recent studies have suggested the potential efficacy of tyrosine kinase inhibitors in managing IPF, masitinib, a clinically used tyrosine kinase inhibitor, has not yet been investigated for its efficacy in fibrotic lung diseases. In a previous study on an in vitro neurodegenerative model, we demonstrated the synergistic antitoxic and antioxidant effects of masitinib combined with cromolyn sodium, an FDA-approved mast cell stabilizer. This study aims to investigate the anti-fibrotic and antioxidant effects of the masitinib-cromolyn sodium combination in an in vitro model of pulmonary fibrosis. Fibroblast cell cultures treated with bleomycin and/or hydrogen peroxide (H2O2) were subjected to masitinib and/or cromolyn sodium, followed by assessments of cell viability, morphological and apoptotic nuclear changes, triple-immunofluorescence labeling, and total oxidant/antioxidant capacities, besides ratio of Bax and Bcl-2 mRNA expressions as an indication of apoptosis. The combined treatment of masitinib and cromolyn sodium effectively prevented the fibroblast myofibroblast transition, a hallmark of fibrosis, and significantly reduced bleomycin / H2O2-induced apoptosis and oxidative stress. This study is the first to demonstrate the additive anti-fibrotic, cell-protective, and antioxidant effects of the masitinib-cromolyn sodium combination in an in vitro fibrosis model, suggesting its potential as an innovative therapeutic approach for pulmonary fibrosis. Combination therapy may be more advantageous in that both drugs could be administered in lower doses, exerting less side effects, and at the same time providing diverse mechanisms of action simultaneously.
Assuntos
Antioxidantes , Apoptose , Benzamidas , Bleomicina , Cromolina Sódica , Fibroblastos , Miofibroblastos , Estresse Oxidativo , Piperidinas , Piridinas , Tiazóis , Antioxidantes/farmacologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Benzamidas/farmacologia , Piridinas/farmacologia , Apoptose/efeitos dos fármacos , Miofibroblastos/efeitos dos fármacos , Miofibroblastos/metabolismo , Piperidinas/farmacologia , Cromolina Sódica/farmacologia , Animais , Tiazóis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Sinergismo Farmacológico , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Fibrose Pulmonar Idiopática/patologia , Células Cultivadas , Camundongos , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/patologiaRESUMO
In contemporary floriculture, particularly within the cut flower industry, there is a burgeoning interest in innovative methodologies aimed at enhancing the aesthetic appeal and prolonging the postharvest longevity of floral specimens. Within this context, the application of nanotechnology, specifically the utilization of silicon and selenium nanoparticles, has emerged as a promising approach for augmenting the qualitative attributes and extending the vase life of cut roses. This study evaluated the impact of silicon dioxide (SiO2-NPs) and selenium nanoparticles (Se-NPs) in preservative solutions on the physio-chemical properties of 'Black Magic' roses. Preservative solutions were formulated with varying concentrations of SiO2-NPs (25 and 50 mg L-1) and Se-NPs (10 and 20 mg L-1), supplemented with a continuous treatment of 3% sucrose. Roses treated with 20 mg L-1 Se-NPs exhibited the lowest relative water loss, highest solution uptake, maximum photochemical performance of PSII (Fv/Fm), and elevated antioxidative enzyme activities. The upward trajectory of hydrogen peroxide (H2O2) and malondialdehyde (MDA) levels in petals was mitigated by different levels of SiO2 and Se-NPs, with the lowest H2O2 and MDA observed in preservatives containing 50 mg L-1 SiO2- and 20 mg L-1 Se-NPs at the 15th day, surpassing controls and other treatments. Extended vase life and a substantial enhancement in antioxidative capacity were noted under Se and Si nanoparticles in preservatives. The levels of total phenols, flavonoids, and anthocyanin increased during the vase period, particularly in the 50 and 20 mg L-1 Se-NPs and SiO2-NPs. Petal carbohydrate exhibited a declining trend throughout the longevity, with reductions of 8% and 66% observed in 20 mg L-1 Se-NPs and controls, respectively. The longest vase life was achieved with Se-NPs (20 mg L-1), followed by SiO2-NPs (50 mg L-1) up to 16.6 and 15th days, respectively. These findings highlight the significant potential of SiO2- and Se-NPs in enhancing the vase life and physiological qualities of 'Black Magic' roses, with SiO2-NPs showing broad-spectrum efficacy.
Assuntos
Flores , Nanopartículas , Rosa , Selênio , Dióxido de Silício , Selênio/química , Selênio/farmacologia , Dióxido de Silício/química , Nanopartículas/química , Rosa/química , Flores/química , Antioxidantes/química , Antioxidantes/farmacologia , Peróxido de Hidrogênio/metabolismo , Malondialdeído/metabolismoRESUMO
Salinity stress represents a major threat to crop production by inhibiting seed germination, growth of seedlings, and final yield and, therefore, to the social and economic prosperity of developing countries. Recently, plant growth-promoting substances have been widely used as a chemical strategy for improving plant resilience towards abiotic stresses. This study aimed to determine whether melatonin (MT) and glycine betaine (GB) alone or in combination could alleviate the salinity-induced impacts on seed germination and growth of maize seedlings. Increasing NaCl concentration from 100 to 200 mM declined seed germination rate (4.6-37.7%), germination potential (24.5-46.7%), radical length (7.7-40.0%), plumule length (2.2-35.6%), seedling fresh (1.7-41.3%) and dry weight (23.0-56.1%) compared to control (CN) plants. However, MT and GB treatments lessened the adverse effects of 100 and 150 mM NaCl and enhanced germination comparable to control plants. In addition, results from the pot experiments show that 200 mM NaCl stress disrupted the osmotic balance and persuaded oxidative stress, presented by higher electrolyte leakage, hydrogen peroxide, superoxide radicals, and malondialdehyde compared to control plants. However, compared to the NaCl treatment, NaCl+MT+GB treatment decreased the accumulation of malondialdehyde (24.2-42.1%), hydrogen peroxide (36.2-44.0%), and superoxide radicals (20.1-50.9%) by up-regulating the activity of superoxide dismutase (28.4-51.2%), catalase (82.2-111.5%), ascorbate peroxidase (40.3-59.2%), and peroxidase (62.2-117.9%), and by enhancing osmolytes accumulation, thereby reducing NaCl-induced oxidative damages. Based on these findings, the application of MT+GB is an efficient chemical strategy for improving seed germination and growth of seedlings by improving the physiological and biochemical attributes of maize under 200 mM NaCl stress.
Assuntos
Betaína , Germinação , Melatonina , Estresse Salino , Plântula , Sementes , Zea mays , Melatonina/farmacologia , Zea mays/efeitos dos fármacos , Zea mays/crescimento & desenvolvimento , Zea mays/fisiologia , Zea mays/metabolismo , Betaína/farmacologia , Betaína/metabolismo , Germinação/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Plântula/fisiologia , Estresse Salino/efeitos dos fármacos , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Cloreto de Sódio/farmacologia , Malondialdeído/metabolismo , Salinidade , Antioxidantes/metabolismo , Peróxido de Hidrogênio/metabolismo , Sinergismo Farmacológico , Estresse Oxidativo/efeitos dos fármacosRESUMO
Oxidative damage to human retinal pigment epithelial (RPE) cells is the main cause of age-related macular degeneration (AMD), in our previous work, we showed that ghrelin has an antioxidative effect on human lens epithelium (HLE) cells, however, the studies of using ghrelin in treating the degenerative diseases of the retina have rarely been reported. In this article, we assessed the effect of ghrelin on preventing oxidative stress induced by hydrogen peroxide (H2O2) in ARPE-19 cells and its mechanism. We observed that pretreatment with ghrelin protected ARPE-19 cells from H2O2-induced cell oxidative injuries and apoptosis responses. Furthermore, an oxidative stress-induced mouse model of AMD was established via injection of sodium iodate (NaIO3) to tail veins, and treatment with ghrelin preserved retinal function, and protected photoreceptors.
Assuntos
Apoptose , Modelos Animais de Doenças , Grelina , Peróxido de Hidrogênio , Degeneração Macular , Estresse Oxidativo , Epitélio Pigmentado da Retina , Estresse Oxidativo/efeitos dos fármacos , Degeneração Macular/etiologia , Degeneração Macular/metabolismo , Degeneração Macular/tratamento farmacológico , Degeneração Macular/prevenção & controle , Animais , Grelina/farmacologia , Grelina/metabolismo , Humanos , Camundongos , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/efeitos dos fármacos , Linhagem Celular , Apoptose/efeitos dos fármacos , Iodatos , Antioxidantes/farmacologia , Camundongos Endogâmicos C57BL , MasculinoRESUMO
BACKGROUND: To minimize the impact of pesticide residues in food on human health, it is necessary to enhance their detection. Recently, many nanozyme-based colorimetric methods for pesticides detection have been developed, however, they often required the assistance of natural enzymes, which made the process and result of methods susceptible to the stability and activity of natural enzymes. To overcome these drawbacks, methods for direct detection of pesticides using nanozymes have been developed, and there are few studies in this field currently. Thus, it is of great research and practical significance to develop more nanozymes-based colorimetric methods for direct detection of pesticides. RESULTS: Dual colorimetric platforms based on Os-Rh nanozyme with excellent peroxidase-like activity were constructed for directly detection of glyphosate in this work. Results showed that glyphosate was able to sensitively and selectively inhibit the peroxidase-like activity of Os-Rh nanozyme through hindering the decomposition of H2O2 by Os-Rh nanozyme to produce HOâ. Based on this, the dual colorimetric platforms achieved highly sensitive detection for glyphosate over a wide linear concentration range (50-1000 µg L-1 in solution platform and 200-1000 µg L-1 in paper platform), with the detection limits of 28.37 µg L-1 in solution platform and 400 µg L-1 (naked-eye detection limit)/123.25 µg L-1 (gray scale detection limit) in paper platform, respectively. Moreover, the dual colorimetric platforms possessed satisfactory reliability and accuracy for practical applications, and has been successfully applied to the detection of real samples with the spiked recoveries of 92.78-102.75 % and RSD of 1.17-3.88 %. SIGNIFICANCE: The dual colorimetric platforms for glyphosate direct detection based on Os-Rh nanozyme developed in this work not only owned considerable practical application potential, but also could provide more inspirations and ideas for the rational design and development of colorimetric sensing methods for the rapid detection of pesticides based on nanozymes.
Assuntos
Colorimetria , Glicina , Glifosato , Colorimetria/métodos , Glicina/análogos & derivados , Glicina/análise , Glicina/química , Peroxidase/metabolismo , Peroxidase/química , Limite de Detecção , Peróxido de Hidrogênio/químicaRESUMO
Pathogenesis-related proteins (PR), including osmotins, play a vital role in plant defense, being activated in response to diverse biotic and abiotic stresses. Despite their significance, the mechanistic insights into the role of osmotins in plant defense have not been extensively explored. The present study explores the cloning and characterization of the osmotin gene (WsOsm) from Withania somnifera, aiming to illuminate its role in plant defense mechanisms. Quantitative real-time PCR analysis revealed significant induction of WsOsm in response to various phytohormones e.g. abscisic acid, salicylic acid, methyl jasmonate, brassinosteroids, and ethrel, as well as biotic and abiotic stresses like heat, cold, salt, and drought. To further elucidate WsOsm's functional role, we overexpressed the gene in Nicotiana tabacum, resulting in heightened resistance against the Alternaria solani pathogen. Additionally, we observed enhancements in shoot length, root length, and root biomass in the transgenic tobacco plants compared to wild plants. Notably, the WsOsm- overexpressing seedlings demonstrated improved salt and drought stress tolerance, particularly at the seedling stage. Confocal histological analysis of H2O2 and biochemical studies of antioxidant enzyme activities revealed higher levels in the WsOsm overexpressing lines, indicating enhanced antioxidant defense. Furthermore, a pull-down assay and mass spectrometry analysis revealed a potential interaction between WsOsm and defensin, a known antifungal PR protein (WsDF). This suggests a novel role of WsOsm in mediating plant defense responses by interacting with other PR proteins. Overall, these findings pave the way for potential future applications of WsOsm in developing stress-tolerant crops and improving plant defense strategies against pathogens.
Assuntos
Defensinas , Regulação da Expressão Gênica de Plantas , Nicotiana , Proteínas de Plantas , Plantas Geneticamente Modificadas , Estresse Fisiológico , Withania , Withania/genética , Withania/fisiologia , Withania/metabolismo , Withania/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Nicotiana/genética , Nicotiana/fisiologia , Nicotiana/efeitos dos fármacos , Nicotiana/microbiologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Estresse Fisiológico/genética , Defensinas/genética , Defensinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Alternaria/fisiologia , Secas , Plântula/genética , Plântula/fisiologia , Plântula/efeitos dos fármacos , Ácido Salicílico/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Peróxido de Hidrogênio/metabolismo , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Raízes de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologiaRESUMO
BACKGROUND: Chemiluminescence (CL) bioassay is one of the most advanced and used detection method in clinical diagnosis and biomedical research because of the advantages of low background, easy operation, and wide-field imaging without a light source or microscope. The luminol/hydrogen peroxide/horseradish peroxidase (luminol/H2O2/HRP) system is the most popular CL system, but its application in high-throughput imaging detection is challenged due to its low luminescence efficiency and flash-type emission which is difficult in ensuring the reproducibility and consistency of detection results. RESULTS: We reported a glow-type CL system of luminol@CD/H2O2/HRP by using a supramolecular enhancer of cyclodextrin (CD). This luminol@CD/H2O2/HRP system exhibited a luminescence lifetime of 41 min for sensitive and accurate imaging analysis. The long-lasting CL emission was attributed to the formation of a 1:1 host-guest complex between luminol and CD, which could stabilize the emitter and effectively reduce nonradiative relaxation. The formation of luminol@CD complex was determined through NMR experiments and theoretical analysis. Under optimum conditions, the luminol@CD/H2O2/HRP system showed higher sensitivity and much better precision than classical luminol/H2O2/HRP system for imaging detection of HRP. Especially, this glow-type luminol@CD/H2O2/HRP system realized CL imaging of microwell arrays on microfluidic chips. In addition, the luminol@CD/H2O2/HRP system was successfully applied for point-of-care detection of 17ß-estradiol based on a competitive mechanism of host-guest recognition. SIGNIFICANCE: An efficient CL system is crucial for obtaining reproducible and consistent results for accurate detection. Our luminol@CD/H2O2/HRP system emitted strong and persistent luminescence, resulting in reliability and efficiency at both CL macroscopic and microscopic imaging detection. We expected the luminol@CD/H2O2/HRP CL system to be applied in various detection fields.
Assuntos
Ciclodextrinas , Peroxidase do Rábano Silvestre , Peróxido de Hidrogênio , Medições Luminescentes , Luminol , Luminol/química , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/análise , Ciclodextrinas/química , Medições Luminescentes/métodos , Peroxidase do Rábano Silvestre/química , Peroxidase do Rábano Silvestre/metabolismo , Humanos , Luminescência , Limite de DetecçãoRESUMO
An in-situ nanozyme signal tag combined with a DNA-mediated universal antibody-oriented strategy was proposed to establish a high-performance immunosensing platform for Alzheimer's disease (AD)-related biomarker detection. Briefly, a Zr-based metal-organic framework (MOF) with peroxidase (POD)-like activity was synthesized to encapsulating the electroactive molecule methylene blue (MB), and subsequently modified with a layer of gold nanoparticles on its surface. This led to the creation of double POD-like activity nanozymes surrounding the MB molecule to form a nanozyme signal tag. A large number of hydroxyl radicals were generated by the nanozyme signal tag with the help of H2O2, which catalyzed MB molecules in situ to achieve efficient signal amplification. Subsequently, a DNA-aptamer-mediated universal antibody-oriented strategy was proposed to enhance the binding efficiency for the antigen (target). Meanwhile, a poly adenine was incorporated at the end of the aptamer, facilitating binding to the gold electrode and providing anti-fouling properties due to the hydrophilicity of the phosphate group. Under optimal conditions, this platform was successfully employed for highly sensitive detection of AD-associated tau protein and BACE1, achieving limits of detection with concentrations of 3.34 fg/mL and 1.67 fg/mL, respectively. It is worth mentioning that in the tau immunosensing mode, 20 clinical samples from volunteers of varying ages were analyzed, revealing significantly higher tau expression levels in the blood samples of elderly volunteers compared to young volunteers. This suggests that the developed strategy holds great promise for early AD diagnosis.
Assuntos
Doença de Alzheimer , Aptâmeros de Nucleotídeos , Biomarcadores , Técnicas Biossensoriais , Técnicas Eletroquímicas , Ouro , Nanopartículas Metálicas , Proteínas tau , Técnicas Biossensoriais/métodos , Humanos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/sangue , Técnicas Eletroquímicas/métodos , Ouro/química , Aptâmeros de Nucleotídeos/química , Biomarcadores/sangue , Nanopartículas Metálicas/química , Proteínas tau/sangue , Estruturas Metalorgânicas/química , Imunoensaio/métodos , Limite de Detecção , Secretases da Proteína Precursora do Amiloide , Azul de Metileno/química , Ácido Aspártico Endopeptidases/sangue , Peróxido de Hidrogênio/química , CatáliseRESUMO
Background: Oral insulin delivery is considered a revolutionary alternative to daily subcutaneous injection. However, the oral bioavailability of insulin is very low due to the poor oral absorption into blood circulation. Methods: To promote penetration across the intestinal epithelium and achieve enhanced and safe glucose-responsive oral insulin delivery, pH and H2O2 dual-sensitive nanoparticles (NPs) were constructed. The NPs were loaded of glucose oxidase (GOx) and insulin by pH and H2O2 dual-sensitive amphiphilic polymer incorporated with phenylboronic ester-conjugated poly(2-hydroxyethyl methacrylate) and poly(carboxybetaine) (PCB). The dual-sensitive NPs were utilized for the treatment of type 1 diabetes mellitus (T1DM) after oral administration. Results: The dual-sensitive NPs could enhance the transport of insulin across the intestinal epithelium into blood facilitated by zwitterionic PCB. By virtue of the generated low pH and high H2O2 with GOx in hyperglycemic environment, the pH and H2O2 dual-sensitive NPs were disassembled to achieve rapid and sustained release of insulin. After oral administration of the dual-sensitive NPs in enteric capsules into T1DM mouse model, the oral bioavailability of insulin reached 20.24%, and the NPs achieved hypoglycemic effect for a few hours longer than subcutaneously injected insulin. Importantly, the pH and H2O2 dual-sensitive NPs could ameliorate the local decline of pH and rise of H2O2 to avoid the toxic side effect. Conclusion: Therefore, this work would provide a promising platform for the enhanced and safe treatment of diabetes mellitus.
Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 1 , Peróxido de Hidrogênio , Hipoglicemiantes , Insulina , Nanopartículas , Animais , Administração Oral , Insulina/administração & dosagem , Insulina/farmacocinética , Nanopartículas/química , Peróxido de Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Camundongos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Diabetes Mellitus Experimental/tratamento farmacológico , Glucose Oxidase/administração & dosagem , Humanos , Sistemas de Liberação de Medicamentos/métodos , Masculino , Glicemia/efeitos dos fármacos , Glucose/metabolismo , Disponibilidade BiológicaRESUMO
INTRODUCTION: Trauma-induced coagulopathy (TIC) refers to an abnormal coagulation process, an imbalance between coagulation and fibrinolysis due to several pathological factors, such as haemorrhage and tissue injury. Platelet activation and subsequent clot formation are associated with mitochondrial activity, suggesting a possible role for mitochondria in TIC. Comprehensive studies of mitochondrial dysfunction in platelets from severe trauma patients have not yet been performed. METHODS: In this prospective case-control study, patients with severe trauma (ISS≥16) had venous blood samples taken at arrival to the Emergency Unit of a Level 1 Trauma Centre. Mitochondrial functional measurements (Oxygraph-2k, Oroboros) were performed to determine oxygen consumption in different respiratory states, the H2O2 production and extramitochondrial Ca2+ movements. In addition, standard laboratory and coagulation tests, viscoelastometry (ClotPro) and aggregometry (Multiplate) were performed. Measurements data were compared with age and sex matched healthy control patients. RESULTS: Severe trauma patients (n = 113) with a median age of 38 years (IQR, 20-51), a median ISS of 28 (IQR, 20-48) met our inclusion criteria. Oxidative phosphorylation in platelet mitochondria from severe trauma patients significantly decreased compared to controls (34.7 ± 8.8 pmol/s/mL vs. 48.0 ± 19.7 pmol/s/mL). The mitochondrial H2O2 production significantly increased and greater endogenous Ca2+ release was found in the polytrauma group. Consistent with these results, clotting time (CT) increased while maximum clot firmness (MCF) decreased with the EX-test and FIB-test in severe trauma samples. Multiplate aggregometry showed significantly decreased ADP-test (38 ± 12 AUC vs. 112 ± 14 AUC) and ASPI test (78 ± 22 AUC vs. 84 ± 28 AUC) also tended to decrease in mitochondria of polytrauma patients as compared with controls. Significant strong correlation has been demonstrated between mitochondrial OxPhos and MCF while it was negatively correlated with ISS (R2=0.448, PË0.05), INR, CT and lactate level of patients. CONCLUSIONS: The present study revealed that severe trauma is associated with platelet mitochondrial dysfunction resulting in reduced ATP synthesis and impaired extramitochondrial Ca2+ movement. These factors are required for platelet activation, recruitment and clot stability likely thus, platelet mitochondrial dysfunction contributes to the development of TIC.
Assuntos
Transtornos da Coagulação Sanguínea , Plaquetas , Mitocôndrias , Ferimentos e Lesões , Humanos , Estudos Prospectivos , Masculino , Estudos de Casos e Controles , Feminino , Adulto , Plaquetas/metabolismo , Ferimentos e Lesões/complicações , Ferimentos e Lesões/sangue , Mitocôndrias/metabolismo , Pessoa de Meia-Idade , Transtornos da Coagulação Sanguínea/etiologia , Transtornos da Coagulação Sanguínea/sangue , Fosforilação Oxidativa , Coagulação Sanguínea/fisiologia , Adulto Jovem , Ativação Plaquetária/fisiologia , Cálcio/metabolismo , Cálcio/sangue , Peróxido de Hidrogênio/metabolismo , Peróxido de Hidrogênio/sangueRESUMO
Glomalin-related soil protein (GRSP) has demonstrated significant potential for water purification and remediation of heavy metals in soils; however, its redox reactivity for As(III) sequestration and the corresponding redox-active component are still poorly understood. This study investigated the photochemical properties of GRSP and its mechanism of oxidation/adsorption of As(III). The results showed that UV irradiation triggered electron transfer and the production of reactive oxygen species (ROS) in GRSP, thereby facilitating As(III) oxidation with promotion rates ranging from 43.34 % to 111.1 %. The oxidation of As(III) occurred both on the GRSP photoforming holes and in the ROS reaction from the oxygen reduction products of the photoforming electrons. OH⢠and H2O2 played an important role in the oxidation of As(III) by GRSP, especially under alkaline conditions. Moreover, the presence of Fe(III) in GRSP facilitated the formation of OH⢠and its the oxidation capacity towards As(III). The binding of As(III) to the -COOH, -OH, and -FeO groups on the GRSP surface occurred through surface complexation. Overall, these findings provided new insights into the roles of the redox-active moieties and Fe(III) on GRSP in the promoted oxidation of As(III), which would help to deepen our understanding of the migration and transformation of As(III) in soils.
Assuntos
Arsênio , Oxirredução , Poluentes do Solo , Arsênio/química , Poluentes do Solo/química , Adsorção , Ferro/química , Raios Ultravioleta , Espécies Reativas de Oxigênio/química , Proteínas Fúngicas/química , Peróxido de Hidrogênio/química , Compostos Férricos/química , Solo/química , GlicoproteínasRESUMO
Nanomaterials, with their small size, surface characteristics, and antibacterial properties, are extensively employed across environmental, energy, biomedical, agricultural, and other industries. This study examined the antibacterial efficacy of magnesium hydroxide (Mg(OH)2) nanoparticles (NPs) against sulfate-reducing bacteria (SRB) within sediments. The inhibitory effects of two types of Mg(OH)2 NPs with distinct particle sizes (20.3 and 29.6 nm) and concentrations (0-10.0 mg/mL) were examined under optimal treatment conditions. The antibacterial mechanisms of Mg(OH)2 NPs through direct contact and dissolution effects were determined. The results revealed a correlation between the concentration, particle size, and inhibitory activity, with the smallest NPs (20.3 nm) at the highest concentration (10.0 mg/mL) substantially reducing SRB counts from 8.77 ± 0.18 to 6.48 ± 0.13 log10 colony forming units/mL after 6 h treatment. Treatment with high concentrations of Mg(OH)2 NPs induced cellular damage, reduced intracellular lactate dehydrogenase activity, and elevated intracellular catalase activity and H2O2 content, suggesting that the contact effect of NPs stimulated SRB. This leads to oxidative stress response and structural damage to the cell membrane, which has emerged as the primary driver of the antibacterial action of Mg(OH)2 NPs. This study presents a novel nanomaterial that can inhibit and control SRB in natural sedimentary environments.
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Antibacterianos , Sedimentos Geológicos , Hidróxido de Magnésio , Sulfatos , Hidróxido de Magnésio/química , Hidróxido de Magnésio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Sedimentos Geológicos/microbiologia , Sulfatos/química , Sulfatos/farmacologia , Nanopartículas/química , Peróxido de Hidrogênio/farmacologia , Tamanho da Partícula , Bactérias/efeitos dos fármacos , Nanopartículas Metálicas/química , Testes de Sensibilidade MicrobianaRESUMO
Plants produce reactive oxygen species (ROS) upon infection, which typically trigger defence mechanisms and impede pathogen proliferation. Root-knot nematodes (RKNs, Meloidogyne spp.) represent highly detrimental pathogens capable of parasitizing a broad spectrum of crops, resulting in substantial annual agricultural losses. The involvement of ROS in RKN parasitism is well acknowledged. In this study, we identified a novel effector from Meloidogyne incognita, named CATLe, that contains a conserved catalase domain, exhibiting potential functions in regulating host ROS levels. Phylogenetic analysis revealed that CATLe is conserved across RKNs. Temporal and spatial expression assays showed that the CATLe gene was specifically up-regulated at the early infection stages and accumulated in the subventral oesophageal gland cells of M. incognita. Immunolocalization demonstrated that CATLe was secreted into the giant cells of the host plant during M. incognita parasitism. Transient expression of CATLe significantly dampened the flg22-induced ROS production in Nicotiana benthamiana. In planta assays confirmed that M. incognita can exploit CATLe to manipulate host ROS levels by directly degrading H2O2. Additionally, interfering with expression of the CATLe gene through double-stranded RNA soaking and host-induced gene silencing significantly attenuated M. incognita parasitism, highlighting the important role of CATLe. Taken together, our results suggest that RKNs can directly degrade ROS products using a functional catalase, thereby manipulating host ROS levels and facilitating parasitism.
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Catalase , Peróxido de Hidrogênio , Nicotiana , Espécies Reativas de Oxigênio , Tylenchoidea , Animais , Peróxido de Hidrogênio/metabolismo , Tylenchoidea/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Nicotiana/parasitologia , Catalase/metabolismo , Catalase/genética , Doenças das Plantas/parasitologia , Raízes de Plantas/parasitologia , Filogenia , Proteínas de Helminto/metabolismo , Proteínas de Helminto/genética , Interações Hospedeiro-ParasitaRESUMO
In plants, a local infection can lead to systemic acquired resistance (SAR) through increased production of salicylic acid (SA). For many years, the identity of the mobile signal and its direct transduction mechanism for systemic SA synthesis in initiating SAR have been debated. We found that in Arabidopsis thaliana, after a local infection, the conserved cysteine residue of the transcription factor CCA1 HIKING EXPEDITION (CHE) undergoes sulfenylation in systemic tissues, which enhances its binding to the promoter of the SA-synthesis gene ISOCHORISMATE SYNTHASE1 (ICS1) and increases SA production. Furthermore, hydrogen peroxide (H2O2) produced through NADPH oxidases is the mobile signal that sulfenylates CHE in a concentration-dependent manner. Accumulation of SA and the previously reported signal molecules, such as N-hydroxypipecolic acid (NHP), then form a signal amplification loop to establish SAR.