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1.
Mikrochim Acta ; 191(2): 120, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38300346

RESUMEN

A highly sensitive and selective fluorescence method has been conducted for the detection of Hg2+ based on aminophenylboronic acid-modified carboxyl magnetic beads (CMB@APBA) and CRISPR/Cas12a system mediated by glyoxal caged nucleic acid (gcDNA). As a bi-functional DNA linker, gcDNA offers advantages of simultaneous recognition by boronic acid and complementary DNA/RNA. Under acidic condition, gcDNA can be immobilized on CMB@APBA through the formation of borate ester bond. The formed boric acid-esterified gcDNA can further bind with complementary CRISPR RNA through A-T base pairing to activate Cas12a with kcat/Km ratio of 3.4 × 107 s-1 M-1, allowing for amplified signal. Hg2+ can specifically combine with CMB@APBA, resulting in the release of gcDNA from CMB@APBA and the following inhibition on the activation of CRISPR/Cas12a system around magnetic bead. Under optimal conditions, the method exhibits a linear range from 20 to 250 nM, with a detection limit of 2.72 nM. The proposed method can detect Hg2+ in milk and tea beverages, providing a great significance for on-site monitoring of Hg2+ contamination in food.


Asunto(s)
Mercurio , Ácidos Nucleicos , Sistemas CRISPR-Cas , ARN , Glioxal
2.
J Food Sci Technol ; 59(12): 4634-4643, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36276544

RESUMEN

In order to improve the function of insoluble dietary fiber (IDF) extracted from pickle, the coupled enzymatic hydrolysis and high hydrostatic pressure treatment method (EHHP) was used to modify its structure. Compared with the unmodified IDF (U-IDF), analysis of the particle size dispersion, bulk density, surface structure monosaccharide composition, microstructure, thermodynamic properties showed that the modified IDF (EHHP-IDF) has a looser and more porous structure, reduced particle size, bulk density, crystal strength and thermal stability, and increased xylose and galactose content. Due to the special looser microstructure, EHHP-IDF has showed the notable capacity of absorption of oil, glucose, nitrite, cholesterol as well as Pb2+. Collectively, these results show that EHHP has good potential use as an ideal modification method to improve the function of IDF, and a novel functional ingredient of EHHP-IDF which could be used in future food processing was obtained in this study.

3.
Small ; 17(52): e2104195, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34729918

RESUMEN

The authors proposed a novel template-free strategy, urease-mediated interfacial growth of NH4 Ga(OH)2 CO3 nanotubes at 20-50 °C, to fabricate the porous Ga2 O3 nanotubes. The subtlety of the proposed strategy is all the products from urea enzymolysis are utilized in formation of NH4 Ga(OH)2 CO3 precipitates, and the key for interfacial growth of NH4 Ga(OH)2 CO3 nanotubes is the dynamic match between the rate of CO2 bubble fusion and NH4 Ga(OH)2 CO3 precipitation. The proposed strategy works well for the doped porous Ga2 O3 nanotubes. As a proof-of-concept, the porous ß-Ga2 O3 and ß-Ga2 O3 :Cr0.001 nanotubes are used as photocatalysts or co-catalysts with Pt, for H2 evolution from water splitting. The H2 evolution rate of porous ß-Ga2 O3 nanotubes reach 39.3 mmol g-1 h-1 with solar-to-hydrogen (STH) conversion efficiency of 2.11% (Hg lamp) or 498 µmol g-1 h-1 with STH of 0.03% (Xe lamp) respectively, both about 3 times of ß-Ga2 O3 nanoparticles synthesized at pH 9.0 without urease. The Cr-doping enhances the in-the-dark H2 evolution rate pre-lighted by Hg lamp, and Pt co-catalysis further elevates the H2 evolution rate, for instance, the H2 evolution rate of Pt-loaded ß-Ga2 O3 :Cr0.001 nanotubes reaches 54.7 mmol g-1 h-1 with STH of 2.94% under continuous lighting of Hg lamp and 1062 µmol g-1 h-1 in-the-dark.


Asunto(s)
Carbonatos , Galio , Hidrógeno , Nanotubos , Ureasa , Catálisis , Porosidad
4.
J Sci Food Agric ; 101(5): 2090-2099, 2021 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-32978811

RESUMEN

BACKGROUND: Lignin extracted from Canna edulis Ker residues shows a strong inhibitory effect on α-glucosidase and a promoting effect on α-amylase. Protease activity inhibition may play a key role in disease processes, such as metastasis, tumor invasion and bacterial colonization. Hence, in the present study, the inhibitory mechanism of lignin on trypsin was examined, including the interaction type, thermodynamic parameters, structure, reaction site and molecular docking. RESULTS: The isolated lignin presented an inhibitory effect on trypsin activity with an IC50 value of 1.35 µmol L-1 . This inhibition was a mixed linear type with a constant Ki of 3.92 µmol L-1 . The lignin could bind with the key amino acid residue Ser195 on the active site of the trypsin molecule to inhibit its activity, and the phenolic hydroxyl group and -OH on the ß-O-4 structure of the lignin molecule were the major groups bound with trypsin. CONCLUSION: These results illustrate the inhibitory effects of Canna edulis residue lignin on protease, which helps with respect to understanding the possible application of lignin in the food industry in functional foods. © 2020 Society of Chemical Industry.


Asunto(s)
Inhibidores de Glicósido Hidrolasas/química , Lignina/química , Extractos Vegetales/química , Inhibidores de Tripsina/química , Zingiberales/química , Sitios de Unión , Cinética , Simulación del Acoplamiento Molecular , Termodinámica , Tripsina/química , alfa-Amilasas , alfa-Glucosidasas/química
5.
Small ; 16(16): e1906861, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32191383

RESUMEN

Tauopathy is a complex disorder associated at the junction of several other pathologies. Intrinsically disordered tau protein remains therapeutically challenging due to its undruggable nature and is a possible reason for monumental failure of several tau-based therapies. Herein, nanogold remodeled tau is reported as a pseudo-nanochaperon and shows therapeutic benefit by passive targeting in transgenic tau P301L mutant mice. Treatment with nanogold polyethylene glycol (Au-PEG) conjugate moderately improves the learning ability of the tau P301L mice that corroborates with diminished phosphorylated tau burden. Circulating total tau level that acts in a prion fashion is significantly reduced upon Au-PEG treatment. Similarly, a high level of tau is found in macaque monkey serum and Au-PEG inhibits amyloidosis of Alzheimer's patients and primate's serum samples ex vivo. Addtionally, brain MRI of an old aged macaque monkey shows the decrease of grey matter, which correlates with mutual loss of grey matter upon progressive dementia as reported. Au-PEG tunes tau and other circulating pro-dementia factors that are present in human AD serum, by remodeling the protein and repairing aberrant proteostasis. Alteration of proteotoxic tau function by nanogold as a kinetic stablizer holds translational potential to combat socially challenging dementia.


Asunto(s)
Enfermedad de Alzheimer , Nanomedicina , Nanopartículas , Tauopatías , Proteínas tau , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Humanos , Macaca , Ratones , Ratones Transgénicos , Tauopatías/tratamiento farmacológico , Proteínas tau/metabolismo
6.
Clin Proteomics ; 15: 40, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30598657

RESUMEN

BACKGROUND: Talaromyces marneffei (TM) is an emerging pathogenic fungus that can cause a fatal systemic mycosis in patients infected with human immunodeficiency virus (HIV). Although global awareness regarding HIV/TM coinfection is increasing little is known about the mechanism that mediates the rapid progression to HIV/AIDS disease in coinfected individuals. The aim of this study was to analyze the serum proteome of HIV/TM coinfected patients and to identify the associated protein biomarkers for TM in patients with HIV/AIDS. METHODS: We systematically used multiplexed isobaric tandem mass tag labeling combined with liquid chromatography mass spectrometry (LC-MS/MS) to screen for differentially expressed proteins in the serum samples from HIV/TM-coinfected patients. RESULTS: Of a total data set that included 1099 identified proteins, approximately 86% of the identified proteins were quantified. Among them, 123 proteins were at least 1.5-fold up-or downregulated in the serum between HIV/TM-coinfected and HIV-mono-infected patients. Furthermore, our results indicate that two selected proteins (IL1RL1 and THBS1) are potential biomarkers for distinguishing HIV/TM-coinfected patients. CONCLUSIONS: This is the first report to provide a global proteomic profile of serum samples from HIV/TM-coinfected patients. Our data provide insights into the proteins that are involved as host response factors during infection. These data shed new light on the molecular mechanisms that are dysregulated and contribute to the pathogenesis of HIV/TM coinfection. IL1RL1 and THBS1 are promising diagnostic markers for HIV/TM-coinfected patients although further large-scale studies are needed. Thus, quantitative proteomic analysis revealed molecular differences between the HIV/TM-coinfected and HIV-mono-infected individuals, and might provide fundamental information for further detailed investigations.

7.
Kidney Blood Press Res ; 43(4): 1375-1387, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30153665

RESUMEN

BACKGROUND/AIMS: To investigate whether the invasively obtained central aortic systolic blood pressure (CSBP) predicts chronic kidney disease (CKD) better than brachial systolic blood pressure (SBP), brachial diastolic blood pressure (DBP) and brachial pulse pressure (PP) in the middle-aged Chinese population. METHODS: A cross-sectional study was carried out across China in 2009-2010 among the subjects aged 35-64 years. CSBP was measured non-invasively by radial artery applanation tonometry B-pro (A-PULSE CASP and corresponding software). CSBP, SBP, DBP and PP were standardized with Z-score and the odds ratios were calculated with multivariable logistic regression model. RESULTS: Data of 10197 participants were analyzed. The multivariable logistic regression after adjusting for possible confounders showed that a 1-standard deviation increment in each blood pressure measurement was associated with greater risk of CKD in both men and women (P < 0.05). The association of CSBP with CKD was stronger than SBP, DBP and PP in women, while in men the association of CSBP with CKD was stronger only than PP. With CSBP and SBP entering into the multivariable logistic regression models jointly, the odds ratio (95% confidence interval) for CSBP and SBP was 1.57 (1.39-1.79) and 1.22 (1.07-1.38) in women and 1.20 (1.03-1.39) and 1.48 (1.28-1.72) in men, respectively. With CSBP and DBP entering into the multivariable logistic regression models jointly, the odds ratio (95% confidence interval) for CSBP and DBP was 1.68 (1.52-1.84) and 1.15 (1.04-1.27) in women and 1.30 (1.15-1.46) and 1.45 (1.29-1.63) in men, respectively. With CSBP and PP entering into the multivariable logistic regression models jointly, the odds ratio (95% confidence interval) for CSBP and PP was 1.75 (1.58-1.94) and 1.06 (0.96-1.17) in women and 1.58 (1.41-1.77) and 1.04 (0.93-1.17) in men, respectively. CONCLUSION: CSBP and brachial blood pressure measurements are all predictors of CKD, however the non-invasively obtained CSBP may offer advantages over brachial blood pressure measurements in CKD risk prediction in women.


Asunto(s)
Aorta/fisiología , Determinación de la Presión Sanguínea/métodos , Arteria Braquial/fisiología , Insuficiencia Renal Crónica/diagnóstico , Adulto , Determinación de la Presión Sanguínea/normas , China , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Insuficiencia Renal Crónica/fisiopatología , Medición de Riesgo , Factores Sexuales
8.
J Sci Food Agric ; 98(4): 1502-1510, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28799644

RESUMEN

BACKGROUND: We synthesised a novel sericin peptide (SP-GI) with α-d-glucosidase inhibitory activity, which has a sequence of SEDSSEVDIDLGN. The kinetics of its peptide-induced inhibition on α-d-glucosidase activity and its interaction mechanism merging with molecular docking were both investigated. RESULTS: SP-GI exhibited significant inhibitory activity with an IC50 of 2.9 ± 0.1 µmol L-1 and this inhibition was reversible and non-competitive with a Ki value of 1.0 ± 0.1 µmol L-1 . An interaction study with SP-GI revealed it bound to α-d-glucosidase at a single binding site, resulting in alterations in α-d-glucosidase secondary structure. This led to quenching of intrinsic α-d-glucosidase fluorescence by a static quenching mechanism. Molecular docking results showed that the SP-GI binding site on α-d-glucosidase differed from acarbose, with hydrogen bonding and van der Waals forces being the main binding drivers. CONCLUSION: These findings suggest the potential use for SP-GI or other natural sericin peptides as dietary supplements for the treatment of type 2 diabetes. © 2017 Society of Chemical Industry.


Asunto(s)
Inhibidores de Glicósido Hidrolasas/química , Péptidos/química , Proteínas de Saccharomyces cerevisiae/antagonistas & inhibidores , Sericinas/química , alfa-Galactosidasa/antagonistas & inhibidores , Sitios de Unión , Cinética , Simulación del Acoplamiento Molecular , Péptidos/síntesis química , Unión Proteica , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Proteínas de Saccharomyces cerevisiae/química , Sericinas/síntesis química , alfa-Galactosidasa/química
9.
J Food Sci Technol ; 55(11): 4406-4412, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30333636

RESUMEN

An extraction method was optimized to get a flavonoid-rich ethanol extract from Angelica keiskei leaves (FREE-AK). Trace elements and total flavonoid content of FREE-AK were identified, and the hypoglycemic and hypolipidemic effects of FREE-AK were studied in streptozotocin-induced diabetic mice. For FREE-AK extraction the optimal conditions were 65% ethanol, 45 °C and 15 min, resulting in a total flavonoid content up to 10.18% and K, Mg, Na, and Ca, content of about 36.59, 1.52, 14.51 and 7.486 mg/g, respectively. FREE-AK uptake could cause a marked decrease of fasting blood glucose and a significant improvement on glucose tolerance in diabetic mice. In addition, FREE-AK treatment with a dose of 800 mg/kg b.w. resulted in a reduction in the total triglyceride level (TC) in serum. Results demonstrated the effectiveness of FREE-AK for hypoglycemia and hypolipidemia in streptozotocin-induced mice and FREE-AK may be a potential dietary treatment for type 2 diabetes.

10.
J Sep Sci ; 40(8): 1755-1764, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28217859

RESUMEN

Aminosilanized magnetic carbon microspheres as a novel adsorbent were designed and fabricated. The adsorbent was used for the magnetic solid-phase extraction of bisphenols at trace levels from environmental water samples before liquid chromatography with tandem mass spectrometry analysis. The structure, surface, and magnetic behavior of the as-prepared aminosilanized magnetic carbon microspheres were characterized by elemental analysis, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, powder X-ray diffraction, and vibrating sample magnetometry. The effects of the experimental parameters were investigated by the Plackett-Burman design, and then the parameters that were significant to the extraction efficiencies were optimized through a response surface methodology. The aminosilanized magnetic carbon microspheres exhibited high adsorption efficiency and selectivity for bisphenols. Under optimal conditions, low limits of detection (0.011-2.22 ng/L), and a wide linear range (2-3 orders of magnitude), good repeatability (4.7-7.8%, n = 5), and reproducibility (6.0-8.3%, n = 3) were achieved. The results demonstrate that the novel adsorbent possesses great potentials in the determination of trace levels of bisphenols in environmental water samples.

11.
Neuroepidemiology ; 46(3): 182-90, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26854473

RESUMEN

The Cardiovascular and Cognitive Health Study (CCHS-Beijing) is a population-based study of cardiovascular disease (CVD) and cognitive impairment in adults aged 55 and older in Beijing. The main aims of the study are to investigate the prevalence rates of CVD, asymptomatic atherosclerosis, and cognitive impairment, as well as validate the risk factors related to the onset and development of CVD, Alzheimer's disease (AD) and mild cognitive impairment (MCI). The study was designed to detect the traditional and new risk factors in this age group. Participants were recruited randomly from residential regions in the greater Beijing municipality area based on the average levels of development in Beijing, China in 2012 (based on socioeconomic, demographic, and geographical characteristics). Thorough physical and laboratory examination were performed at baseline (also the cross-sectional survey) to identify the risk factors such as hypertension, dyslipidemia, diabetes, as well as newly defined risk factors like elevated homocysteine, high sensitivity C-reactive protein, and urine micro-albumin. Subclinical disease of the cerebral vasculature included atherosclerosis of carotid arteries, intracranial arteries, and retinal vessels. Subclinical cardiac diseases included left ventricular enlargement, arrhythmias, chamber hypertrophy and myocardial ischemia. Blood pressure was documented using the ankle-arm method. In addition, neuropsychological assessments were performed for all subjects aged 65 and above. Baseline evaluation began during the period August 2013 to December 2014. Follow-up examination will occur in 5 years. The initial and recurrent CVD, AD and MCI events will be verified and validated during the follow-up period.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/epidemiología , Diseño de Investigaciones Epidemiológicas , Estado de Salud , Anciano , Beijing/epidemiología , Enfermedades Cardiovasculares/metabolismo , Trastornos del Conocimiento/metabolismo , Estudios de Cohortes , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Distribución Aleatoria
12.
ScientificWorldJournal ; 2014: 810185, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24574920

RESUMEN

Human complex action recognition is an important research area of the action recognition. Among various obstacles to human complex action recognition, one of the most challenging is to deal with self-occlusion, where one body part occludes another one. This paper presents a new method of human complex action recognition, which is based on optical flow and correlated topic model (CTM). Firstly, the Markov random field was used to represent the occlusion relationship between human body parts in terms of an occlusion state variable. Secondly, the structure from motion (SFM) is used for reconstructing the missing data of point trajectories. Then, we can extract the key frame based on motion feature from optical flow and the ratios of the width and height are extracted by the human silhouette. Finally, we use the topic model of correlated topic model (CTM) to classify action. Experiments were performed on the KTH, Weizmann, and UIUC action dataset to test and evaluate the proposed method. The compared experiment results showed that the proposed method was more effective than compared methods.


Asunto(s)
Modelos Neurológicos , Percepción de Movimiento , Flujo Optico , Humanos , Percepción Espacial
13.
J Sci Food Agric ; 94(8): 1505-12, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24127206

RESUMEN

BACKGROUND: In view of the high nutritional values and bioactivities of resistant starch and pectin, it would be a good choice to chemically combine pectin and starch to give a new type of chemically modified resistant starch. RESULT: A new type of chemically modified resistant starch has been prepared by cross-linking starch and pectin using sodium trimetaphosphate. Starch-pectin conjugates can well prevent the hydrolysis catalysed by different enzymes, such as α-amylase, amyloglucosidase, pancreatin as well as ß-amylase and glucosidase. Although the conjugates do not change the crystal type of starch, they increase the degree of crystallinity. Moreover, thermal stability and structural homogeneity of the conjugates are positively correlated with double-helical order in the crystalline region. CONCLUSION: This study gives a new method for the preparation of resistant starch-pectin conjugates which can be widely used as a new type of food additive in the industry.


Asunto(s)
Pectinas/química , Almidón/química , Fenómenos Químicos , Reactivos de Enlaces Cruzados , Cristalización , Estabilidad de Medicamentos , Aditivos Alimentarios , Glucano 1,4-alfa-Glucosidasa/metabolismo , Glucosidasas/metabolismo , Calor , Hidrólisis , Pancreatina/metabolismo , Polifosfatos , alfa-Amilasas/metabolismo , beta-Amilasa/metabolismo
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(5): 1259-63, 2014 May.
Artículo en Zh | MEDLINE | ID: mdl-25095418

RESUMEN

Unsupervised learning algorithm-principal component analysis (PCA), and supervised learning algorithm-learning vector quantization (LVQ) neural network and support vector machine (SVM) were used to carry out qualitative discriminant analysis of different varieties of coix seed from different regions. Since nutrient compositions of different varieties coix seed samples from different origins were complex and the contents were similar, characteristic variables of two kinds of coix seed were alike, the scores plot of their principal components seriously overlapped and the categories of coix seed were difficult to distinguish While satisfactory results were obtained by LVQ neural network and SVM. The accuracy of LVQ neural network prediction is 90. 91%, while the classification accuracy of SVM, whose penalty parameter and kernel function parameter were optimized, can be up to 100%. The results show that NIRS combined with chemometrics can be used as a rapid, nondestructive and reliable method to identify coix seed varieties and provide technical reference for market regulation.


Asunto(s)
Coix/clasificación , Semillas/clasificación , Espectroscopía Infrarroja Corta , Algoritmos , Análisis Discriminante , Redes Neurales de la Computación , Análisis de Componente Principal , Máquina de Vectores de Soporte
15.
iScience ; 27(6): 109943, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38868194

RESUMEN

In scenarios involving the treatment of complex or coexisting diseases with multiple drugs, the potential for severe adverse drug reactions in patients necessitates the identification of potential drug-drug interactions (DDIs). Most existing computational methods have not taken into account the asymmetry and relation types of drug interactions caused by the relation information between drugs, which may lead to missing information in embedded learning. Therefore, this paper proposes a directed relation graph attention aware network (DRGATAN) to predict asymmetric drug interactions. DRGATAN leverages an encoder to learn multi-relational role embeddings of drugs across different types of relations. The experimental results show that DRGATAN's performance is superior to recognized advanced methods. The visualization demonstrates the effect of utilizing asymmetric information, and the case analysis validates the reliability of the proposed method. This study provides guidance for predicting asymmetric drug interactions.

16.
RSC Adv ; 14(26): 18182-18191, 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38854833

RESUMEN

In the growing body of scientific literature, the structure and information of drugs are usually represented in two-dimensional vector graphics. Drug compound structures in vector graphics form are difficult to recognize and utilize by computers. Although the current OCSR paradigm has shown good performance, most existing work treats it as a single isolated whole. This paper proposes a multi-stage cognitive neural network model that predicts molecular vector graphics more finely. Based on cognitive methods, we construct a model for fine-grained perceptual representation of molecular images from bottom to top, and in stages, the primary representation of atoms and bonds is potential discrete label sequence (atom type, bond type, functional group, etc.). The second stage represents the molecular graph according to the label sequence, and the final stage evolves in an extensible manner from the molecular graph to a machine-readable sequence. Experimental results show that MMSSC-Net outperforms current advanced methods on multiple public datasets. It achieved an accuracy rate of 75-94% on cognitive recognition at different resolutions. MMSSC-Net uses a sequence cognitive method to make it more reliable in interpretability and transferability, and provides new ideas for drug information discovery and exploring the unknown chemical space.

17.
Food Chem ; 454: 139735, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38795621

RESUMEN

Arsenite (As3+), a highly carcinogenic heavy metal ion and widely distributed in nature, can have serious health implications even with minimal exposure. Herein, a portable smartphone device-based ratiometric fluorescence platform was established for sensitive detection of As3+. The work relied on the use of metal-organic framework-tagged cDNA (PCN-224-cDNA), with high adsorption capability and fluorescence properties, as an internal reference to quench the fluorescence of FAM-anchored aptamer (FAM-Apt) via hybridization. In the presence of As3+, FAM-Apt specifically bound to As3+ leading to conformational changes, which detached from the PCN-224-cDNA surface. Interestingly, a smartphone-based readout equipment engineered using a 3D-printed hardware device administered the portable detection of As3+. The limit of detection (LOD) for the proposed ratiometric biosensor was calculated to be 0.021 ng/mL, significantly below WHO's safety threshold. Hence, it demonstrates significant potential for large-scale screening of As3+ residues in food and the environment.


Asunto(s)
Técnicas Biosensibles , Límite de Detección , Teléfono Inteligente , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Arsenitos/análisis , Fluorescencia , Aptámeros de Nucleótidos/química , Contaminación de Alimentos/análisis , Espectrometría de Fluorescencia/instrumentación , Espectrometría de Fluorescencia/métodos , Exonucleasas/metabolismo , Exonucleasas/química
18.
Insect Sci ; 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38196174

RESUMEN

Aphids, the important global agricultural pests, harbor abundant resources of symbionts that can improve the host adaptability to environmental conditions, also control the interactions between host aphid and natural enemy, resulting in a significant decrease in efficiency of biological control. The facultative symbiont Serratia symbiotica has a strong symbiotic association with its aphid hosts, a relationship that is known to interfere with host-parasitoid interactions. We hypothesized that Serratia may also influence other trophic interactions by interfering with the physiology and behavior of major predators to provide host aphid defense. To test this hypothesis, we investigated the effects of Serratia on the host aphid Acyrthosiphon pisum and its predator, the ladybeetle Propylaea japonica. First, the prevalence of Serratia in different A. pisum colonies was confirmed by amplicon sequencing. We then showed that harboring Serratia improved host aphid growth and fecundity but reduced longevity. Finally, our research demonstrated that Serratia defends aphids against P. japonica by impeding the predator's development and predation capacity, and modulating its foraging behavior. Our findings reveal that facultative symbiont Serratia improves aphid fitness by disrupting the predation strategy of ladybeetle larvae, offering new insight into the interactions between aphids and their predators, and providing the basis of a new biological control strategy for aphid pests involving the targeting of endosymbionts.

19.
ACS Appl Mater Interfaces ; 15(37): 44109-44118, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37676637

RESUMEN

Organophosphorus pesticides (OPPs) are extensively used in agricultural production, and the contamination caused by their residues has raised significant concerns regarding potential threats to human health. Herein, a novel fluorescence nanoprobe based on an enzyme-mediated silver nanoparticle-modified metal organic framework (AgNPs@PCN-224) was successfully prepared for the rapid detection of OPPs. Initially, AgNPs@PCN-224 were synthesized by reducing silver nitrate (AgNO3) using sodium borohydride (NaBH4) embedded into luminescent PCN-224. This triggered the inner filter effect, leading to fluorescence quenching. Meanwhile, under the catalysis of acetylcholinesterase (AChE) and choline oxidase (CHO), acetylcholine (ATCh) was decomposed to hydrogen peroxide (H2O2), which could destroy AgNPs to form Ag+ released from PCN-224 for fluorescence recovery. Instead, fenitrothion, an OPP, inhibited AChE activity, allowing the quenched fluorescence to be reactivated. Under the current optimum conditions, the fluorescence intensity had a good correlation (Y = -728.5370X + 2178.4248, R2 = 0.9869) over a dynamic range of fenitrothion concentrations from 0.1 to 500 ng/mL, with an LOD of 0.037 ng/mL. In addition, the anti-interference ability and robustness of the proposed sensor was verified for the monitoring of fenitrothion in tea with recoveries of 87.67-103.72% and the relative standard deviations (RSD) < 5.43%, indicating that the system has excellent prospects for OPP determination in practical applications. Furthermore, this work provides a universal platform for screening other enzyme inhibitors to detect OPPs.


Asunto(s)
Nanopartículas del Metal , Plaguicidas , Humanos , Fluorescencia , Acetilcolinesterasa , Fenitrotión , Peróxido de Hidrógeno , Compuestos Organofosforados , Plata
20.
Food Chem X ; 18: 100675, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37122553

RESUMEN

Honeysuckle leaves are rich in bioactive ingredients, but often considered as agro-wastes. In this study, honeysuckle leaf extract (HLE) was added to the carboxymethyl konjac glucomannan/konjac glucomannan/gelatin composite edible film (CMKH). Compared to films without HLE addition (CMK), the water vapor barrier properties of CMKH slightly decreased, but the transmittance of the CMKH films in UV region (200-400 nm) as low as zero. The elongation at break of CMKH film was 1.39 âˆ¼ 1.5 fold higher than those of CMK films. The DPPH and ABTS scavenging activity of CMKH-Ⅱ was 85.75% and 90.93%, respectively, which is similar to the equivalent content of Vc. The inhibition rate of CMKH-Ⅰ and CMKH-Ⅱ against Escherichia coli and Listeria monocytogenes were close to 90%, and the inhibition rate against Staphylococcus aureus were up to 96%. The results emphasized that the composite film containing 25% (v/v) HLE has potential application value in food preservation.

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