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1.
Biochem Genet ; 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886317

RESUMEN

Ferroptosis is a novel form of membrane-dependent cell death that differs from other cell death modalities such as necrosis, apoptosis, and autophagy. Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system primarily affecting brain and spinal cord neurons. Although the pathogenesis of these two conditions may seem unrelated, recent studies have indicated a connection between ferroptosis and multiple sclerosis. In fact, ferroptosis plays a significant role in the development of MS, as evidenced by the presence of elevated iron levels and iron metabolism abnormalities in the brains, spinal cords, and other neurons of MS patients. These abnormalities disrupt iron homeostasis within cells, leading to the occurrence of ferroptosis. However, there is currently a lack of research on the diagnostic value of ferroptosis-related genes in multiple sclerosis. In this study, we employed bioinformatics methods to identify ferroptosis-related genes (ATM, GSK3B, HMGCR, KLF2, MAPK1, NFE2L1, NRAS, PCBP1, PIK3CA, RPL8, VDAC3) associated with the diagnosis of multiple sclerosis and constructed a diagnostic model. The results demonstrated that the diagnostic model accurately identified the patients' condition. Subsequently, subgroup analysis was performed based on the expression levels of ferroptosis-related genes, dividing patients into high and low expression groups. The results showed differences in immune function and immune cell infiltration between the two groups. Our study not only confirms the correlation between ferroptosis and multiple sclerosis but also demonstrates the diagnostic value of ferroptosis-related genes in the disease. This provides guidance for clinical practice and direction for further mechanistic research.

2.
Plant Mol Biol ; 102(4-5): 389-401, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31894456

RESUMEN

KEY MESSAGE: This study revealed that the Arabidopsis UGT75B1 plays an important role in modulating ABA activity by glycosylation when confronting stress environments. The cellular ABA content and activity can be tightly controlled in several ways, one of which is glycosylation by family 1 UDP-glycosyltransferases (UGTs). Previous analysis has shown UGT75B1 activity towards ABA in vitro. However, the biological role of UGT75B1 remains to be elucidated. Here, we characterized the function of UGT75B1 in abiotic stress responses via ABA glycosylation. GUS assay and qRT-PCR indicated that UGT75B1 is significantly upregulated by adverse conditions, such as osmotic stress, salinity and ABA. Overexpression of UGT75B1 in Arabidopsis leads to higher seed germination rates and seedling greening rates upon exposure to salt and osmotic stresses. In contrast, the big UGT75B1 overexpression plants are more sensitive under salt and osmotic stresses. Additionally, the UGT75B1 overexpression plants showed larger stomatal aperture and more water loss under drought condition, which can be explained by lower ABA levels examined in UGT75B1 OE plants in response to water deficit conditions. Consistently, UGT75B1 ectopic expression leads to downregulation of many ABA-responsive genes under stress conditions, including ABI3, ABI5 newly germinated seedlings and RD29A, KIN1, AIL1 in big plants. In summary, our results revealed that the Arabidopsis UGT75B1 plays an important role in coping with abiotic stresses via glycosylation of ABA.


Asunto(s)
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimología , Regulación de la Expresión Génica de las Plantas , Glucosiltransferasas/fisiología , Glicosiltransferasas/metabolismo , Estrés Fisiológico , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Catálisis , Sequías , Genes de Plantas , Germinación , Glucosiltransferasas/genética , Glicosilación , Glicosiltransferasas/genética , Presión Osmótica , Plantas Modificadas Genéticamente/genética , Salinidad , Plantones/genética , Plantones/fisiología , Cloruro de Sodio , Factores de Transcripción/genética , Factores de Transcripción/fisiología
3.
Acta Cardiol Sin ; 36(4): 343-350, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32675926

RESUMEN

BACKGROUND: Anemia caused by left ventricular outflow tract obstruction in patients with hypertrophic obstructive cardiomyopathy (HOCM) has been reported, however, large clinical studies confirming this association are lacking. The objective of the present study was to investigate the relationship between left ventricular outflow tract (LVOT) pressure gradient and hemoglobin in patients with hypertrophic cardiomyopathy (HCM). METHODS: Patient demographics, laboratory and echocardiography data from 310 patients diagnosed with HCM from our hospital who had undergone echocardiography from July 2014 to March 2019 were collected from medical records. Patients were classified into HOCM and non-HOCM groups. RESULTS: Compared to the non-HOCM group, patients in the HOCM group had a lower hemoglobin level (112.2 ± 16.7 vs. 132.9 ± 22.2 g/L, p < 0.001). In addition, significant negative correlations between hemoglobin and LVOT pressure gradient were found in males (r = -0.568, p < 0.001) and females (r = -0.589, p < 0.001). Receiver operating characteristic curve analysis revealed that the best cut-off value for hemoglobin to predict HOCM in male patients was 128 g/L with 74.19% sensitivity and 75.51% specificity (area under the curve: 0.763, p < 0.001). For female patients, the cut-off value was 125 g/L, with a sensitivity and specificity of 89.39% and 48.48%, respectively (area under the curve: 0.718, p < 0.001). CONCLUSIONS: Our results indicate that hemoglobin level is inversely proportional to the LVOT gradient pressure and has value for predicting outflow tract obstruction in patients with HCM.

4.
Environ Sci Technol ; 53(24): 14296-14307, 2019 12 17.
Artículo en Inglés | MEDLINE | ID: mdl-31738526

RESUMEN

The physicochemical properties of engineered nanomaterials can change drastically during aging in the environment. Understanding how these changes influence protein corona formation on nanomaterials is critical for accurately predicting the human exposure risks of aged nanomaterials. Here, we show that sulfidation, a prevalently occurring environmental aging process, of Ag and ZnO nanomaterials significantly affected the protein compositions of the hard corona formed in human saliva, sweat, and bronchoalveolar lavage fluid, corresponding to three most common exposure pathways, that is, ingestion, dermal contact, and inhalation. In particular, a diverse variety of proteins selectively associated with either sulfidized or pristine nanomaterials. Random forest classification of the proteomic data revealed that this selective protein adsorption process was mainly dictated by electrostatic interaction, hydrophobic interaction, and steric hindrance between proteins and nanomaterials, which were susceptible to the changes in surface charge, hydrophobicity, and aggregation status of nanomaterials induced by sulfidation. Furthermore, even for the proteins that do not exhibit distinct adsorption selectivity between sulfidized and pristine nanomaterials, sulfidation altered the extents of impact of nanomaterials on the conformation and likely functions of the adsorbed proteins. These findings unearth a previously neglected mechanism via which environmental sulfidation process mediates the biological effects of soft-metal-containing nanomaterials.


Asunto(s)
Nanoestructuras , Corona de Proteínas , Óxido de Zinc , Humanos , Proteómica , Plata
5.
Bull Environ Contam Toxicol ; 102(5): 721-729, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30756128

RESUMEN

Mercury contamination in soil and water has become a major concern to environmental quality and human health. Among the existing remediation technologies for mercury pollution control, sorption via iron-based materials has received wide attention as they are environmental friendly and economic, and their reactivity is high and controllable through modulating the morphology and surface properties of particulate materials. This paper aimed to provide a comprehensive overview on environmental application of a variety of iron-based sorbents, namely, zero valent iron, iron oxides, and iron sulfides, for mercury remediation. Techniques to improve the stability of these materials while enhancing mercury sequestration, such as nano-scale size control, surface functionalization, and mechanical support, were summarized. Mechanisms and factors affecting the interaction between mercury and iron-based materials were also discussed. Current knowledge gaps and future research needs are identified to facilitate a better understanding of molecular-level reaction mechanisms between iron-based materials and mercury and the long-term stability of the immobilized mercury.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Hierro/química , Mercurio/aislamiento & purificación , Contaminantes del Suelo/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Suelo
6.
J Fluoresc ; 27(4): 1495-1503, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28508151

RESUMEN

Indole propionic acid (IPA) is one of the important plant growth hormones for promoting rooting and fruiting. Labeling IPA receptor in plant tissues is able to further track the signal transduction processes of IPA and uncover the function mechanism of IPA on crop productions. In this paper, a tunable and nontoxic fluorescent probe for IPA receptors was designed and synthetized base on carbon dots (C dots). Firstly carboxyl-modified carbon dots were prepared by high temperature cracking of citric acid. The fluorescence emission wavelengths of C dots varied with the excitation wavelengths change. Then IPA-modified carbon dots (IPA-C dots) were prepared by coupling the amino of tryptophan with the carboxyl of as-prepared carbon dots. Compared with C dots, the fluorescence intensity of IPA-C dots was double and the fluorescence stability was satisfactory under various conditions. This probe retained the biological activity of IPA and acted as target recognition of IPA receptors in plant tissues. The probe could avoid green fluorescence background of plants. The imaging results showed that the IPA receptors mainly existed on the membrane of stele. The toxicity test indicated the probe was less toxic than traditional inorganic semiconductor quantum dots.


Asunto(s)
Carbono/química , Fluorescencia , Colorantes Fluorescentes/química , Imagen Molecular/métodos , Puntos Cuánticos/química , Receptores de Superficie Celular/metabolismo , Vigna/metabolismo , Indoles , Plantones/metabolismo
7.
Luminescence ; 30(1): 18-25, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24833131

RESUMEN

The determination of hormone-binding sites in plants is essential in understanding the mechanisms behind hormone function. Salicylic acid (SA) is an important plant hormone that regulates responses to biotic and abiotic stresses. In order to label SA-binding sites in plant tissues, a quantum dots (QDs) probe functionalized with a SA moiety was successfully synthesized by coupling CdSe QDs capped with 3-mercaptopropionic acid (MPA) to 4-amino-2-hydroxybenzoic acid (PAS), using 1-ethyl-3-(3-dimethyllaminopropyl) carbodiimide (EDC) as the coupling agent. The probe was then characterized by dynamic light scattering and transmission electron microscopy, as well as UV/vis and fluorescence spectrophotometry. The results confirmed the successful conjugation of PAS to CdSe QDs and revealed that the conjugates maintained the properties of the original QDs, with small core diameters and adequate dispersal in solution. The PAS-CdSe QDs were used to detect SA-binding sites in mung bean and Arabidopsis thaliana seedlings in vitro and in vivo. The PAS-CdSe QDs were effectively transported into plant tissues and specifically bound to SA receptors in vivo. In addition, the effects of the PAS-CdSe QDs on cytosolic Ca(2+) levels in the tips of A. thaliana seedlings were investigated. Both SA and PAS-CdSe QDs had similar effects on the trend in cytosolic-free Ca(2+) concentrations, suggesting that the PAS-CdSe QDs maintained the bioactivity of SA. To summarize, PAS-CdSe QDs have high potential as a fluorescent probe for the in vitro/in vivo labeling and imaging of SA receptors in plants.


Asunto(s)
Arabidopsis/química , Compuestos de Cadmio/química , Puntos Cuánticos , Ácido Salicílico/análisis , Semillas/química , Compuestos de Selenio/química , Sitios de Unión , Compuestos de Cadmio/síntesis química , Compuestos de Cadmio/aislamiento & purificación , Tamaño de la Partícula , Compuestos de Selenio/síntesis química , Compuestos de Selenio/aislamiento & purificación , Propiedades de Superficie
8.
Pharm Biol ; 52(2): 162-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24073926

RESUMEN

CONTEXT: Ginsenosides are primary active ingredients of ginseng, which are believed to have various health benefits. It is found that the biotransformation of ginsenosides mainly takes place in the gastrointestinal tract and the information about ginsenosides-exerted effects on intestinal contractility is not sufficient. AIMS: The present study proposed that ginsenosides could exert stimulatory or inhibitory effects on intestinal motility depending on the assay condition-related intestinal contractile states and was to characterize the effects of ginsenosides on intestinal motility. METHODS: Jejunal contractility determination, Western blotting analysis, and real-time polymerase chain reaction were performed to test the effects of total ginsenosides isolated from Panax ginseng C. A. Mey (Araliaceae) root. RESULTS: The results showed that ginsenosides at the fixed concentration of 20 mg/L exerted bidirectional regulation (BR) on the contractility of isolated jejunal segment (IJS), depending on the contractile states. The contractility of IJS was increased by ginsenosides in low contractile states, which were correlated to the cholinergic activation, and the contractility of IJS was decreased by ginsenosides in high contractile states, which were correlated to the adrenergic activation and nitric oxide related mechanisms. Ginsenosides-induced BR was abolished in the absence of Ca(2+) or by using tetrodotoxin, implicating the requirement of Ca(2+) and the enteric nervous system. Effects of ginsenosides on myosin light chain phosphorylation and the mRNA expression of myosin light chain kinase were also bidirectional. DISCUSSION AND CONCLUSION: Results suggest that ginsenosides may have the potential clinical implication for reliving the symptoms of alternative hypo- and hyper-intestinal motility.


Asunto(s)
Motilidad Gastrointestinal/efectos de los fármacos , Ginsenósidos/farmacología , Contracción Muscular/efectos de los fármacos , Panax/química , Animales , Western Blotting , Calcio/metabolismo , Sistema Nervioso Entérico/metabolismo , Femenino , Ginsenósidos/aislamiento & purificación , Yeyuno/efectos de los fármacos , Yeyuno/metabolismo , Masculino , Cadenas Ligeras de Miosina/metabolismo , Quinasa de Cadena Ligera de Miosina/genética , Fosforilación/efectos de los fármacos , Raíces de Plantas , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Tetrodotoxina/farmacología
9.
Korean J Physiol Pharmacol ; 18(1): 47-53, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24634596

RESUMEN

In this study, we propose that diprophylline exerts bidirectional modulation (BM) on the isolated rat jejunal segment depending on its contractile state. The results supported the hypothesis. Diprophylline (20 µM) exerted stimulatory effects on the contractility of jejunal segment in six low contractile states while inhibitory effects in six high contractile states, showing the characteristics of BM. Diprophylline-induced stimulatory effect was significantly blocked by atropine, indicating the correlation with cholinergic activation. Diprophylline-induced inhibitory effect was partially blocked by phentolamine, propranolol, and L-N-Nitro-Arginine respectively, indicating their correlation with sympathetic activation and nitric oxide-mediated relaxing mechanisms. Diprophylline-induced BM was abolished by tetrodotoxin or in a Ca(2+) free condition or pretreated with tyrosine kinase inhibitor imatinib, suggesting that diprophylline-induced BM is Ca(2+) dependent, and that it requires the presence of enteric nervous system as well as pacemaker activity of interstitial cells of Cajal. Diprophylline significantly increased the reduced MLCK expression and myosin extent in constipation-prominent rats and significantly decreased the increased MLCK expression and myosin extent in diarrhea-prominent rats, suggesting that the change of MLCK expression may also be involved in diprophylline-induced BM on rat jejunal contractility. In summary, diprophylline-exerted BM depends on the contractile states of the jejunal segments, requires the presence of Ca(2+), enteric nervous system, pacemaker activity of interstitial cells of Cajal, and MLCK-correlated myosin phosphorylation. The results suggest the potential implication of diprophylline in relieving alternative hypo/hyper intestinal motility.

10.
Polymers (Basel) ; 16(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38674999

RESUMEN

The branched structures of dendronized polymers can provide good steric stabilization for metal nanoparticle catalysts. In this work, an amphiphilic dendronized copolymer containing hydrophilic branched triethylene glycol moieties and hydrophobic branched ferrocenyl moieties is designed and prepared by one-pot ring-opening metathesis polymerization, and is used as the stabilizer for metal (Au, Ag and Pd) nanoparticles. These metal nanoparticles (Au nanoparticles: 3.5 ± 3.0 nm; Ag nanoparticles: 7.2 ± 4.0 nm; Pd nanoparticles: 2.5 ± 1.0 nm) are found to be highly active in both the 4-nitrophenol reduction and Suzuki-Miyaura reactions. In the 4-nitrophenol reduction, Pd nanoparticles have the highest catalytic ability (TOF: 2060 h-1). In addition, Pd nanoparticles are also an efficient catalyst for Suzuki-Miyaura reactions (TOF: 1980 h-1) and possess good applicability for diverse substrates. The amphiphilic dendronized copolymer will open a new door for the development of efficient metal nanoparticle catalysts.

11.
Int J Biol Macromol ; 258(Pt 1): 128912, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38141716

RESUMEN

Photocatalysts immobilized on hydrogels is a win-win mode, which not only improves photocatalysis but also successfully prevents catalyst loss, making it easy to separate and reuse during catalytic process. Here, ZnO-Ti3C2TX photocatalysts are loaded into the chitosan/polyacrylic acid hydrogel networks, realizing the efficiently photocatalytic degradation of norfloxacin. The chitosan-based composite hydrogel features rich functional groups and a dense pore structure, which is beneficial to antibiotic enrichment and photocatalytic degradation. The effects of different catalyst ratios, dosage, initial concentrations and pH on the degradation efficiency are investigated. The norfloxacin degradation rate constant is 0.012 min-1 and its degradation efficiency reaches up to 90 % after 240 min. Importantly, the photocatalytic composite hydrogel still retains 85 % degradation efficiency after 6 cycles. Moreover, e- plays a significant role in the degradation process. This work converts the traditional powder photocatalysts into bulk photocatalysts (photocatalytic hydrogels) to accomplish efficient degradation and rapid recycling for contaminant removal.


Asunto(s)
Resinas Acrílicas , Quitosano , Óxido de Zinc , Óxido de Zinc/química , Norfloxacino , Quitosano/química , Hidrogeles , Titanio/química
12.
World J Nucl Med ; 23(1): 33-42, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38595841

RESUMEN

Objective The purpose of this study was to evaluate the prognostic significance of corrected baseline metabolic parameters in fluorodeoxyglucose positron emission tomography imaging ( 18 F-FDG PET/CT) for 3-year progression-free survival (PFS) in patients with primary diffuse large B cell lymphoma (DLBCL). Patients and Methods Retrospective clinical and pathological data were collected for 199 patients of DLBCL diagnosed between January 2018 and January 2021. All patients underwent 18 F-FDG PET/CT scans without any form of treatment. The corrected maximum standardized uptake value (corSUVmax), corrected mean standardized uptake value (corSUVmean), corrected whole-body tumor metabolic volume sum (corMTVsum), and corrected total lesion glycolysis of whole body (corTLGtotal) were corrected using the SUVmean in a 1-cm diameter mediastinal blood pool (MBP) from the descending thoracic aorta of patients. Kaplan-Meier survival curves and Cox regression were used to examine the predictive significance of corrected baseline metabolic parameters on 3-year PFS of patients. The incremental values of corrected baseline metabolic parameters were evaluated by using Harrell's C-indices, receiver operating characteristic, and Decision Curve Analysis. Results The multivariate analysis revealed that only the National Comprehensive Cancer Network (NCCN)-International Prognostic Index (IPI) and corMTVsum had an effect on 3-year PFS of patients ( p < 0.05, respectively). The Kaplan-Meier survival analysis demonstrated significant differences in PFS between the risk groups classified by corSUVsum, corMTVsum, and corTLGtotal (log-rank test, p < 0.05). The predictive model composed of corMTVsum and corTLGtotal surpasses the predictive performance of the model incorporating MTVsum and TLGtotal. The optimal performance was observed when corMTVsum was combined with NCCN-IPI, resulting in a Harrell's C index of 0.785 and area under the curve values of 0.863, 0.891, and 0.947 for the 1-, 2-, and 3-year PFS rates, respectively. Conclusion The corMTVsum offers significant prognostic value for patients with DLBCL. Furthermore, the combination of corMTVsum with the NCCN-IPI can provide an accurate prediction of the prognosis.

13.
Acta Biomater ; 178: 320-329, 2024 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-38479677

RESUMEN

Stress-induced corrosion impairs the mechanical integrity of magnesium (Mg) and its alloys as potential orthopedic implants. Although there has been extensive work reporting the effects of stress on Mg corrosion in vitro, the geometric design principles of the Mg-based orthopedic devices still remain largely unknown. In this work, a numerical simulation model mimicking fractured bone fixation and surgical animal models were applied to investigate the effects of the geometric design of Mg screws on the stress distribution and the stress-induced degradation behavior. Finite element (FE) analysis was used for calculation of stress concentrations around the Mg screws, with different thread type, thread pitch, and thread width. Afterward, the Mg screws of the pre-optimization and post-optimization groups exhibiting the highest and lowest stress concentrations, respectively, were implanted in the fractured distal femora and back subcutaneous tissue of rabbits. Encouragingly, there was a significant difference between the pre-optimization and the post-optimization groups in the degradation rate of the stressed screw parts located around the fracture line. Interestingly, there was no significant difference between the two groups in the degradation rate of the non-stressed screw parts. Consistently, the Mg screw post-optimization exhibited a significantly lower degradation rate than that pre-optimization in the back subcutaneous implantation model, which generated stress in the whole screw body. The alteration in geometric design did not affect the corrosion rate of the Mg screws in an immersion test without load applied. Importantly, an accelerated new bone formation with less fibrous encapsulation around the screws was observed in the Mg group post-optimization relative to the Mg group pre-optimization and the poly (lactic acid) group. Geometry optimization may be a promising strategy to reduce stress-induced corrosion in Mg-based orthopedic devices. STATEMENT OF SIGNIFICANCE: Stress concentrations influence corrosion characteristics of magnesium (Mg)-based implants. The geometric design parameters, including thread type, thread pitch, and thread width of the Mg screws, were optimized through finite element analysis to reduce stress concentrations in a fractured model. The Mg screws with triangular thread type, 2.25 mm pitch, and 0.3 mm thread width, exhibiting the lowest maximum von Mises stress, showed a significant decrease in the volume loss relative to the Mg screws pre-optimization. Compared with the Mg screw pre-optimization and the poly(lactic acid) screw, the Mg screw post-optimization favored new bone formation while inhibiting fibrous encapsulation. Collectively, optimization in the geometric design is a promising approach to reduce stress-induced corrosion in Mg-based implants.


Asunto(s)
Fracturas del Fémur , Curación de Fractura , Animales , Conejos , Magnesio/farmacología , Corrosión , Tornillos Óseos , Fracturas del Fémur/cirugía , Análisis de Elementos Finitos , Fenómenos Biomecánicos
14.
Environ Sci Pollut Res Int ; 31(13): 19815-19830, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38367117

RESUMEN

Against the backdrop of ecological conservation and high-quality development in the Yangtze River Basin, there is an increasing demand for enhanced water pollution prevention and control in small watersheds. To delve deeper into the intricate relationship between pollutants and environmental features, as well as explore the key factors triggering pollution and their corresponding warning thresholds, this study was conducted along the Jiuqu River, a strategically managed unit in the upstream region of the Yangtze River, between 2022 and 2023. A total of seven monitoring sites were established, from which 161 valid water samples were collected. The k-nearest neighbors mutual information (KNN-MI) technique indicated that water temperature (WT) and relative humidity (RH) were the main environmental factors. The principal component analysis (PCA) of ten water quality parameters and three environmental factors unveiled the distinguishing characteristics of the primary pollution sources. Consequently, the pollution sources were categorized as treated wastewater > groundwater runoff > phytoplankton growth > abstersion wastewater > agricultural drainage. Furthermore, the regression decision tree (RDT) algorithm was used to explore the combined effects between pollutants and environmental factors, and to provide visual decision-making process and quantitative results for understanding the triggering mechanism of organic pollution in Jiuqu River. It conclusively identifies total phosphorus (TP) as the predominant triggering parameter with the threshold of 0.138 mg/L. The study is helpful to deal with potential water pollution problems preventatively and shows the interpretability and predictive performance of the RDT algorithm in water pollution prevention.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Monitoreo del Ambiente/métodos , Ríos , Aguas Residuales , Contaminantes Químicos del Agua/análisis , Contaminación del Agua/análisis , Calidad del Agua , China , Contaminantes Ambientales/análisis
15.
Carbohydr Polym ; 327: 121677, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38171688

RESUMEN

With the growing demand for eco-friendly materials in wearable smart electronic devices, renewable, biocompatible, and low-cost hydrogels based on natural polymers have attracted much attention. Cellulose, as one of the renewable and degradable natural polymers, shows great potential in wearable smart electronic devices. Multifunctional conductive cellulose-based hydrogels are designed for flexible electronic devices by adding sodium carboxymethyl cellulose and MXene into polyacrylic acid networks. The multifunctional hydrogels possess excellent mechanical property (stress: 310 kPa; strain: 1127 %), toughness (206.67 KJ m-3), conductivity (1.09 ± 0.12 S m-1) and adhesion (82.19 ± 3.65 kPa). The multifunctional conductive hydrogels serve as strain sensors (Gauge Factor (GF) = 5.79, 0-700 % strain; GF = 14.0, 700-900 % strain; GF = 40.36, 900-1000 % strain; response time: 300 ms; recovery time: 200 ms) and temperature sensors (Temperature coefficient of resistance (TCR) = 2.5755 °C-1 at 35 °C- 60 °C). The sensor detects human activities with clear and steady signals. A distributed array of flexible sensors is created to measure the magnitude and distribution of pressure and a hydrogel-based flexible touch keyboard is also fabricated to recognize writing trajectories, pressures and speeds. Furthermore, a flexible hydrogel-based supercapacitor powers the LED and exhibits good cyclic stability over 15,000 charge-discharge cycles.

16.
Int J Biol Macromol ; 266(Pt 1): 131248, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38554912

RESUMEN

Renewable biomass-based materials have a huge potential to replace petroleum-based products in food packaging. Herein, pectin/gelatin films loaded with curcumin and silver nanoparticles (AgNPs) are prepared by solution-pouring technology to serve as antimicrobial multifunctional food packaging films. AgNPs and curcumin are found to equally distribute in the films. Fourier transform infrared spectroscopy (FT-IR) reveal the hydrogen bonding and electrostatic interaction among curcumin, AgNPs, pectin and gelatin. The composite films show good antioxidant activity, mechanical performance, hydrophobicity and antibacterial ability. The films of P-GCA 0.5 showed 99.57 ± 0.16 % and 100 % inhibition against E. coli and S. aureus, respectively. The films also demonstrate excellent water vapor barrier qualities. In addition, the composite films possess pH-responsive color change behaviors from yellow (pH 3-8) to light red (pH 8-9) to dark red (pH 11-12), which is suitable for monitoring the freshness of shrimp packaging based on pH changes during deterioration process. As sustainable biomass-based materials, the multifunctional composite films are promising in intelligent food packaging applications.


Asunto(s)
Antibacterianos , Curcumina , Escherichia coli , Embalaje de Alimentos , Gelatina , Nanopartículas del Metal , Pectinas , Plata , Staphylococcus aureus , Embalaje de Alimentos/métodos , Gelatina/química , Plata/química , Nanopartículas del Metal/química , Pectinas/química , Antibacterianos/química , Antibacterianos/farmacología , Curcumina/química , Curcumina/farmacología , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Concentración de Iones de Hidrógeno , Antioxidantes/química , Antioxidantes/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Pruebas de Sensibilidad Microbiana
17.
Artículo en Inglés | MEDLINE | ID: mdl-38062739

RESUMEN

Aim: Acetaminophen (APAP) is clinically recommended as analgesic and antipyretic among pregnant women. However, accumulating laboratory evidence shows that the use of APAP during pregnancy may alter fetal development. Since fetal stage is a susceptible window for early oogenesis, we aim to assess the potential effects of maternal administration of APAP on fetal oocytes. Results: Pregnant mice at 14.5 dpc (days post-coitus) were orally administered with APAP (50 and 150mg/kg.bw/day) for 3 days; meanwhile, 14.5 dpc ovaries were collected and cultured with APAP or its metabolite N-acetyl-p-benzoquinone imine (NAPQI; 5 and 15 µM) for 3 days. It showed that APAP caused meiotic aberrations in fetal oocytes through its metabolite NAPQI, including meiotic prophase I (MPI) progression delay and homologous recombination defects. Co-treatment with nicotinamide (NAM) or nicotinamide riboside chloride (NRC), nicotinamide adenine dinucleotide (NAD+) supplements, efficiently restored the MPI arrest, whereas the addition of the inhibitor of sirtuin 7 (SIRT7) invalidated the effect of the NAD+ supplement. In addition, RNA sequencing revealed distorted transcriptomes of fetal ovaries treated with NAPQI. Furthermore, the fecundity of female offspring was affected, exhibiting delayed primordial folliculogenesis and puberty onset, reduced levels of ovarian hormones, and impaired developmental competence of MII oocytes. Innovation: These findings provide the first known demonstration that NAPQI, converted from maternal administration of APAP, disturbs meiotic process of fetal oocytes and further impairs female fecundity in adulthood. The concomitant oral dosing with NAM further supports the benefits of NAD+ supplements on oogenesis. Conclusion: Short-term administration of APAP to pregnant mouse caused meiotic aberrations in fetal oocytes by its metabolite NAPQI, whereas co-treatment with NAD+ supplement efficiently relieves the adverse effects by interacting with SIRT7.

18.
Biosens Bioelectron ; 251: 116119, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38342057

RESUMEN

Poly (3,4-ethylenedioxythiophene) (PEDOT)-based molecularly imprinted electrochemical sensors have attracted widespread attention for monitoring contaminants in food and the environment. However, there are still problems such as poor hydrophilicity, easy agglomeration, and low selectivity in its preparation. In this work, a novel molecularly imprinted composite hollow sphere was prepared by a molecular imprinting technique using nitrogen-doped hollow carbon spheres as matrix material, and PEDOT and poly(methacrylic acid) as monomers. The selective binding capabilities and mechanism of the material to norfloxacin (NOR) were systematically investigated. Then the material-based sensor was constructed, and its electrochemical detection performance toward NOR was thoroughly studied. The sensor exhibited a wide linear range (0.0005-31 µM), a low detection limit (0.061 nM), satisfactory immunity to interference and stability. Besides, the sensor displayed better sensitivity and reliability (spiked recoveries of 98.0-105.2%, relative standard deviation of 3.45-5.69%) for detecting NOR in lake water, honey, and milk than high-performance liquid chromatography. This work provides a new strategy for developing poly(3,4-ethylenedioxythiophene)-based molecularly imprinted electrochemical sensors.


Asunto(s)
Técnicas Biosensibles , Impresión Molecular , Norfloxacino , Reproducibilidad de los Resultados , Técnicas Electroquímicas/métodos , Polímeros/química , Técnicas Biosensibles/métodos , Impresión Molecular/métodos , Límite de Detección , Electrodos
19.
Food Chem ; 449: 139114, 2024 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-38581782

RESUMEN

L-Tryptophan (L-Trp) is essential for the human body and can only be obtained externally. It is important to develop a method to efficiently detect L-Trp in food. In this work, ionic liquid (IL) modified poly(3,4-ethylendioxythiophene)/ Titanium carbide (PEDOT/Ti3C2TX) was used as a substrate material to improve detection sensitivity. Molecular imprinted polymers (MIP) film for specific recognition of L-Trp was fabricated on the surface of modified electrodes using electrochemical polymerization. The monitoring results showed that the molecularly imprinted electrochemical sensors (MIECS) exhibited good linearity ranges (10-6 - 0.1 µM and 0.1-100 µM) with a low detection limit (LOD) of 2.09 × 10-7 µM. In addition, the MIECS exhibited remarkable stability, reproducibility, and immunity to interference. A good recovery (93.54-99.59%) was demonstrated in the detection of milk. The sensor was expected to be developed as a highly selective and sensitive portable assay, and applied to the detection of L-Trp in food.


Asunto(s)
Técnicas Electroquímicas , Líquidos Iónicos , Límite de Detección , Leche , Impresión Molecular , Polímeros , Titanio , Triptófano , Leche/química , Líquidos Iónicos/química , Polímeros/química , Animales , Técnicas Electroquímicas/instrumentación , Técnicas Electroquímicas/métodos , Triptófano/análisis , Triptófano/química , Titanio/química , Compuestos Bicíclicos Heterocíclicos con Puentes/química , Polímeros Impresos Molecularmente/química , Contaminación de Alimentos/análisis , Electrodos , Reproducibilidad de los Resultados
20.
Carbohydr Polym ; 310: 120726, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-36925251

RESUMEN

Biopolymer-derived hydrogels with low-cost and sustainable features have been considered as fascinating supported materials for metal nanoparticles. Cellulose, as the most abundant biopolymer, is a renewable raw material to prepare biopolymer-derived hydrogels for catalysis. Here, a cellulose-based hydrogel is designed to load bimetallic (AuAg, AuPd and AgPd) nanoparticles. 4-Nitrophenol reduction and Suzuki-Miyaura coupling reactions are selected to evaluate and compare the catalytic performance of the resulting bimetallic nanoparticle-loaded cellulose-based composite hydrogels. The bimetallic nanocomposite hydrogels are easy to be recycled over 10 times during the catalytic experiments and possess good applicability and generality for various substrates. The catalytic activity of bimetallic nanocomposite hydrogels was compared with recent literatures. In addition, the possible catalytic mechanism is also proposed. This work is expected to give a new insight for designing and preparing bimetallic nanoparticle-based cellulose hydrogels and proves its applicability and prospect in the catalytic field.

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