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1.
J Environ Sci (China) ; 148: 198-209, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39095157

RESUMEN

Norfloxacin is widely used owing to its strong bactericidal effect on Gram-negative bacteria. However, the residual norfloxacin in the environment can be biomagnified via food chain and may damage the human liver and delay the bone development of minors. Present work described a reliable and sensitive smartphone colorimetric sensing system based on cobalt-doped Fe3O4 magnetic nanoparticles (Co-Fe3O4 MNPs) for the visual detection of norfloxacin. Compared with Fe3O4, Co-Fe3O4 MNPs earned more remarkably peroxidase-like activity and TMB (colorless) was rapidly oxidized to oxTMB (blue) with the presence of H2O2. Interestingly, the addition of low concentration of norfloxacin can accelerate the color reaction process of TMB, and blue deepening of the solution can be observed with the naked eye. However, after adding high concentration of norfloxacin, the activity of nanozyme was inhibited, resulting in the gradual fading of the solution. Based on this principle, a colorimetric sensor integrated with smartphone RGB mode was established. The visual sensor exhibited good linearity for norfloxacin monitoring in the range of 0.13-2.51 µmol/L and 17.5-100 µmol/L. The limit of visual detection was 0.08 µmol/L. In the actual water sample analysis, the spiked recoveries of norfloxacin were over the range of 95.7%-104.7 %. These results demonstrated that the visual sensor was a convenient and fast method for the efficient and accurate detection of norfloxacin in water, which may have broad application prospect.


Asunto(s)
Cobalto , Colorimetría , Norfloxacino , Teléfono Inteligente , Contaminantes Químicos del Agua , Norfloxacino/análisis , Colorimetría/métodos , Cobalto/análisis , Cobalto/química , Contaminantes Químicos del Agua/análisis , Antibacterianos/análisis , Peroxidasa , Límite de Detección
2.
Integr Zool ; 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39252516

RESUMEN

Desert rodent communities spread plant seeds through the group effect of "selection complementation" and "fate complementation," which promotes the recovery of plant populations and the reconstruction of plant communities in desert areas.

3.
Dalton Trans ; 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39224067

RESUMEN

Two o-carborane-hybridized macrocyclic arenes have been synthesized via Friedel-Crafts alkylation of carborane diaryl derivatives. The single-crystal X-ray diffraction analysis clearly revealed their cavity structure and intermolecular interaction force. These novel macrocycles exhibited aggregation-induced luminescence and intramolecular charge transfer properties and also significant selectivity towards nitro explosive compounds. This work provided a method for the synthesis of hybridized macrocyclic arenes.

4.
J Adv Res ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39233001

RESUMEN

INTRODUCTION: Methyl jasmonate (MeJA) and MYB transcription factors (TFs) play important roles in pathogen resistance in several plants, but MYB TFs in conjunction with MeJA-induced defense against Pseudomonas tolaasii in edible mushrooms remain unknown. OBJECTIVES: To investigate the role of a novel 3R-MYB transcription factor (AbMYB11) in MeJA-induced disease resistance of Agaricus bisporus and in the resistance of transgenic Arabidopsis to P. tolaasii. METHODS: Mushrooms were treated with MeJA alone or in combination with phenylpropanoid pathway inhibitors, and the effects of the treatments on the disease-related and physiological indicators of the mushrooms were determined to assess the role of MeJA in inducing resistance and the importance of the phenylpropanoid pathway involved. Subcellular localization, gene expression analysis, dual-luciferase reporter assay, electrophoretic mobility shift assay, and transgenic Arabidopsis experiments were performed to elucidate the molecular mechanism of AbMYB11 in regulating disease resistance. RESULTS: MeJA application greatly improved mushroom resistance to P. tolaasii infection, and suppression of the phenylpropanoid pathway significantly weakened this effect. MeJA treatment stimulated the accumulation of phenylpropanoid metabolites, which was accompanied by increased the activities of biosynthetic enzymes and the expression of phenylpropanoid pathway-related genes (AbPAL1, Ab4CL1, AbC4H1) and an AbPR-like gene, further confirming the critical role of the phenylpropanoid pathway in MeJA-induced responses to P. tolaasii. Importantly, AbMYB11, localized in the nucleus, was rapidly induced by MeJA treatment under P. tolaasii infection; it transcriptionally activated the phenylpropanoid pathway-related and AbPR-like genes, and AbMYB11 overexpression in Arabidopsis significantly increased the transcription of phenylpropanoid-related genes, the accumulation of total phenolics and flavonoids, and improved resistance to P. tolaasii. CONCLUSION: This study clarified the pivotal role of AbMYB11 as a regulator in disease resistance by modulating the phenylpropanoid pathway, providing a novel idea for the breeding of highly disease-resistant edible mushrooms and plants.

5.
Anal Methods ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263759

RESUMEN

Water environments contaminated by heavy metal ions present significant challenges because these pollutants do not degrade naturally, leading to their gradual bioaccumulation in animals and plants, which ultimately poses an insurmountable threat to human health. Therefore, rapid and accurate detection of heavy metal ions in water is of great significance for environmental protection and disease prevention. In this work, we developed a novel method based on microfluidic electrophoresis coupled with indirect chemiluminescence for the immediate detection of Cd(II), Pb(II) and Hg(II) heavy metal ions. The displacement of the Co(II) ions within the chemiluminescence mixture by the above migrating sample cations caused a measurable reduction in the background signal. The results showed that the detection limits of Cd(II), Pb(II) and Hg(II) ions under the best detection conditions were 5.83 × 10-8 M, 5.38 × 10-8 M and 2.09 × 10-8 M, respectively, which were 1-2 orders of magnitude lower than those of the indirect UV method and 1 order of magnitude lower than that of the indirect laser induced detection method. This method can provide a possibility for the rapid detection of multiple heavy metal ions in actual water environments.

6.
Open Med (Wars) ; 19(1): 20230893, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39221034

RESUMEN

Insulin-like growth factor binding protein 2 (IGFBP2) is overexpressed in tumor tissues of several malignancies, including pancreatic cancer. Because of its role in tumor progression, IGFBP2 has been investigated as a tumor biomarker. However, little is known about its utility in pancreatic cancer. Plasma IGFBP2 levels were determined using enzyme-linked immunosorbent assay in 75 patients with pancreatic ductal adenocarcinoma (PDAC), 73 matched healthy controls, and 17 chronic pancreatitis patients. Our results showed that the plasma IGFPB2 level was significantly higher in PDAC patients than in patients with chronic pancreatitis and healthy controls. At a cut-off value of 333.9 ng/mL, the specificity and sensitivity were 78.08 and 65.33%, respectively. IGFBP2 level alone did not outperform carbohydrate antigen 19-9 (CA19-9) in diagnostic accuracy, but it successfully identified 9 out of 24 PDAC patients who were misidentified by CA19-9. The combination of IGFBP2 and CA19-9 was more accurate in the detection of PDAC than CA19-9 alone. IGFBP2 was more accurate than the other in discriminating between chronic pancreatitis and PDAC. Plasma IGFBP2, rather than CA19-9, was higher in the new-onset diabetes, lymph node involvement, and distant metastasis subgroups. IGFBP2 level was notably higher in stage IV cases than in stage I/II or stage III disease. However, CA19-9 did not show a difference between stages. After adjusting for lymph node involvement and distant metastasis, plasma IGFBP2 was identified as an independent prognostic marker for PDAC. The median survival time for patients with an IGFBP2 level ≥333.9 ng/mL was significantly shorter than that for patients with an IGFBP2 level <333.9 ng/mL. Marked elevation of plasma IGFBP2 in PDAC is associated with poorer survival. IGFBP2 may be considered as a supplementary biomarker for the diagnosis and prognostic prediction in Chinese pancreatic cancer patients.

9.
Nano Lett ; 24(35): 11043-11050, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39162252

RESUMEN

Coupled nanomechanical resonators have unveiled fascinating physical phenomena, including phonon-cavity coupling, coupled energy decay pathway, avoided crossing, and internal resonance. Despite these discoveries, the mechanisms and control techniques of nonlinear mode coupling phenomena with internal resonances require further exploration. Here, we report on the observation of stochastic switching between the two resonance states with coupled 1:1 internal resonance, for resonant two-dimensional (2D) molybdenum disulfide (MoS2) nanoelectromechanical systems (NEMS), which is directly driven to the critical coupling regime without parametric pumping. We further demonstrate that the probability of state switching is linearly tunable from ∼0% to ∼100% by varying the driving voltage. Furthermore, we gradually increase the white noise amplitude and show that the probability of obtaining the higher-energy state decreases, and the stochastic switching phenomenon eventually disappears. The results provide insights into the dynamics of coupled NEMS resonators and open up new possibilities for sensing and stochastic computing.

10.
Chem Commun (Camb) ; 60(72): 9825-9828, 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39171402

RESUMEN

We integrated a pair of donor-acceptor photothermal units, a Lewis acidic site, and a nucleophilic catalytic site into a multi-component metal-organic framework, resulting in an efficient photothermal catalytic system for the conversion of CO2 to cyclic carbonates.

12.
ACS Appl Mater Interfaces ; 16(33): 44202-44209, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39134470

RESUMEN

Radiation detectors based on metal halide perovskite (MHP) single crystals (SCs) have exhibited exceptional sensitivity, low detection limit, and remarkable energy resolution. However, the operational stability issue still dramatically impedes their commercialization due to degradation induced by high-energy irradiation and large bias. Here, we propose an innovative infrared healing strategy to restore the devices that have undergone severe damage from both long-term biasing and X-ray irradiation. Compared to the slow and inefficient intrinsic self-healing process of MHPs, the infrared healing method demonstrates the capacity to achieve rapid recovery of the detection performance of the degraded devices within just 1 h. We reveal that the healing mechanism is mainly related to the reduction of the ion-migration activation energy in MHP SCs under infrared illumination, which promotes the back diffusion of the displaced ions to their original lattice positions and remedies defects. Finally, the healing effect is further confirmed through the gamma-ray spectroscopy acquisition with degraded MHP SCs, whose energy resolution at 59.5 keV of 241Am source is improved from 36% to 12% following infrared illumination. These results present infrared healing as a simple and economic method to extend the service life of MHP SC-based detectors.

13.
Front Nutr ; 11: 1460675, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39206305

RESUMEN

Introduction: The microalga Chlorella sp. NeZha, recently isolated from a balcony environment, shows significant adaptability across various salinity conditions, including seawater (SeaW), freshwater (FreshW), and high salinity levels (45‰). This study investigates its potential for sustainable aquaculture and biotechnological applications. Methods: Morphological and genetic identification were conducted using optical microscopy and DNA sequencing. The microalga was cultivated in a 400 L outdoor photobioreactor, and its biochemical composition, including chlorophyll a, carbohydrate, protein, and lipid content, was analyzed. Its compatibility with zooplankton and growth in aquaculture wastewater were also evaluated. Results: Chlorella sp. NeZha produced chlorophyll a at concentrations exceeding seaweed and Spirulina by 10- and 5-fold, respectively, with a dry weight chlorophyll a content of 34.25 mg/g and 25 pg./cell. The microalga also contained carbohydrate (~33%), protein (~20%), and lipids (~14%). It was compatible with zooplankton species, such as rotifers and brine shrimp, and showed promising growth in aquaculture wastewater. Discussion: The findings suggest that Chlorella sp. NeZha is a viable candidate for sustainable aquaculture and biotechnological applications, offering high nutritional value and environmental resilience. Its adaptability to diverse salinity conditions and ability to thrive in wastewater highlight its potential for bioremediation and use as feedstock for zooplankton. Further research is recommended to optimize its cultivation and explore broader applications.

14.
Animals (Basel) ; 14(16)2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39199868

RESUMEN

As the most abundant group of mammals, rodents possess a very rich ecotype, which makes them ideal for studying the relationship between diet and host gut microecology. Zokors are specialized herbivorous rodents adapted to living underground. Unlike more generalized herbivorous rodents, they feed on the underground parts of grassland plants. There are two species of the genus Myospalax in the Eurasian steppes in China: one is Myospalax psilurus, which inhabits meadow grasslands and forest edge areas, and the other is M. aspalax, which inhabits typical grassland areas. How are the dietary choices of the two species adapted to long-term subterranean life, and what is the relationship of this diet with gut microbes? Are there unique indicator genera for their gut microbial communities? Relevant factors, such as the ability of both species to degrade cellulose, are not yet clear. In this study, we analyzed the gut bacterial communities and diet compositions of two species of zokors using 16S amplicon technology combined with macro-barcoding technology. We found that the diversity of gut microbial bacterial communities in M. psilurus was significantly higher than that in M. aspalax, and that the two species of zokors possessed different gut bacterial indicator genera. Differences in the feeding habits of the two species of zokors stem from food composition rather than diversity. Based on the results of Mantel analyses, the gut bacterial community of M. aspalax showed a significant positive correlation with the creeping-rooted type food, and there was a complementary relationship between the axis root-type-food- and the rhizome-type-food-dominated (containing bulb types and tuberous root types) food groups. Functional prediction based on KEGG found that M. psilurus possessed a stronger degradation ability in the same cellulose degradation pathway. Neutral modeling results show that the gut flora of the M. psilurus has a wider ecological niche compared to that of the M. aspalax. This provides a new perspective for understanding how rodents living underground in grassland areas respond to changes in food conditions.

15.
Angew Chem Int Ed Engl ; : e202409951, 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39177482

RESUMEN

Mesoporous metal‒organic frameworks (MOFs) are promising supports for the immobilization of enzymes, yet their applications are often limited by small pore apertures that constrain the size of encapsulated enzymes to below 5 nm. In this study, we introduced labile linkers (4,4',4''-(2,4,6-boroxintriyl)-tribenzoate, TBTB) with dynamic boroxine bonds into mesoporous PCN-333, resulting in PCN-333-TBTB with enhanced enzyme loading and protection capabilities. The selective breaking of B-O bonds creates defects in PCN-333, which effectively expands both window and cavity sizes, thereby unlocking hidden mesopores for enzyme encapsulation. Consequently, this strategy not only increases the adsorption kinetics of small enzymes (<5 nm) such as cytochrome c (Cyt C) and horseradish peroxidase (HRP), but also enables the immobilization of various large-sized enzymes (>5 nm), such as glycoenzymes. The glycoenzymes@PCN-333-TBTB platform was successfully applied to synthesize thirteen complex oligosaccharides and polysaccharides, demonstrating high activity and enhanced enzyme stability. The dynamic linker-mediated enzyme encapsulation strategy enables the immobilization of enzymes exceeding the inherent pore size of MOFs, thus broadening the scope of enzymatic catalytic reactions achievable with MOF materials.

16.
Pract Lab Med ; 41: e00422, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39155970

RESUMEN

Objectives: We aimed to evaluate the analytical performance of second-trimester maternal serum screening in China, and to compare if there are differences in sigma levels across different methods and months. Methods: A retrospective study was conducted to assess the analytical quality levels of laboratories by calculating the Sigma metrics with prenatal screening biomarkers: AFP, Total ß-hCG, free ß-hCG, uE3. Data from 591 laboratories were selected. Sigma metrics were computed using the formula: Sigma metrics(σ) = (%TEa - |%Bias|)/%CV. The Friedman test and Mann-Whitney test were used to compare differences across various methods and different months. The Hodges-Lehmann was used for determining 95 % confidence intervals of pseudo-medians. Results: Only uE3 showed significant monthly variations in sigma calculations. However, around 8 % of laboratories across all four analytes demonstrated sigma levels both above 6 and below 3 in different months. Laboratories utilizing time-resolved fluorescence methods significantly outperformed those using chemiluminescence in sigma level. For AFP, the pseudo-median difference between these methods lies within a 95 % confidence interval of (-3.22, -1.93), while for uE3, it is at (-2.30, -1.40). Notably, the median sigma levels for all analytes reached the 4-sigma threshold, with free ß-hCG even attaining the 6-sigma level. Conclusion: With current standards, China's second-trimester maternal serum screening is of relatively high analytical quality, and variations in sigma levels exist across different months and methods.

18.
Curr Med Chem ; 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39108010

RESUMEN

BACKGROUND: It is evident that long non-coding RNAs (lncRNAs) are implicated in the pathogenesis of periodontitis. However, the detailed functional mechanisms remain unknown. OBJECTIVE: This study aimed to elucidate the pathogenic mechanisms of lncRNAs in periodontitis by investigating their regulation of protein-coding gene expression. METHOD: Human Gingival Fibroblasts-1 (HGF-1) were stimulated with 5 µg/mL of Lipopolysaccharide (LPS) for 24 hours to construct the periodontitis cell model. qRTPCR and western blot analyses were carried out to determine mRNA and protein levels of genes induced by LPS or involved in the inflammatory response. Cytokine levels and inflammatory proteins were assayed using ELISA. Transcriptome sequencing and analysis were conducted to reveal the expression signatures of lncRNAs. DESeq2 (v1.4.5) was used to analyze differentially expressed genes. Gene function enrichment was carried out using Phyper. AnimalTFDB v3.0 was used to analyze transcription factors involved in the pathogenesis of periodontitis. Prot\ein domains and families of the target proteins were identified based on the Pfam protein family database. RESULTS: In LPS-treated HGF-1 cells, we detected the secretion of TNF-α and IL-1ß, along with the production of MDA and ROS, indicating that LPS significantly triggered inflammatory responses and oxidative stress in HGF-1 cells. A total of 15,295 lncRNAs were detected in both the control (ConT) and LPS-treated groups. We selected 10 significantly differentially co-expressed lncRNA-coding genes (MIR222HG, SNHG15, SNHG12, URS00005F6AA3, URS00009C153E, URS0000D57D7F, URS00019A4688, URS00019AF240, URS00019C6526, and URS0001A00B79) as potential biomarkers for diagnosing the progression of periodontitis. An interaction network consisting of 2 lncRNA- encoding genes (MIR222HG and SNHG15) and protein-encoding genes (CBX5, NUPR1, CHAC1, and MAB21L3) may be involved in the pathogenesis of periodontitis. The ceRNA network analysis revealed the differentially expressed lncRNAs to be involved in inflammatory response, immune infiltration, collagen fiber synthesis, and bone remodeling in LPS-induced periodontitis. CONCLUSION: This study has identified pivotal molecules implicated in the pathogenesis of periodontitis, including those involved in inflammation regulation, collagen fiber synthesis, and bone remodeling. Our findings may contribute to explaining how lncRNAs participate in the pathological process of periodontitis.

19.
Nanoscale Horiz ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39140287

RESUMEN

Visual adaptation is essential for optimizing the image quality and sensitivity of artificial vision systems in real-world lighting conditions. However, additional modules, leading to time delays and potentially increasing power consumption, are needed for traditional artificial vision systems to implement visual adaptation. Here, an ITO/PMMA/SiC-NWs/ITO photoelectric synaptic device is developed for compact artificial vision systems with the visual adaption function. The theoretical calculation and experimental results demonstrated that the heating effect, induced by the increment light intensity, leads to the photoelectric synaptic device enabling the visual adaption function. Additionally, a visual adaptation artificial neuron (VAAN) circuit was implemented by incorporating the photoelectric synaptic device into a LIF neuron circuit. The output frequency of this VAAN circuit initially increases and then decreases with gradual light intensification, reflecting the dynamic process of visual adaptation. Furthermore, a visual adaptation spiking neural network (VASNN) was constructed to evaluate the photoelectric synaptic device based visual system for perception tasks. The results indicate that, in the task of traffic sign detection under extreme weather conditions, an accuracy of 97% was achieved (which is approximately 12% higher than that without a visual adaptation function). Our research provides a biologically plausible hardware solution for visual adaptation in neuromorphic computing.

20.
Materials (Basel) ; 17(15)2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39124431

RESUMEN

Direct current (DC) bias induced by the DC transmission and geomagnetically induced current is a critical factor in the abnormal operation of electrical equipment and is widely used in the field of power transmission and distribution system state evaluation. As the main affected component, the vector magnetization state of a transformer core under DC bias has rarely been studied, resulting in inaccurate transformer operation state estimations. In this paper, a dynamic vector hysteresis model that considers the impact of rotating and DC-biased fields is introduced into the numerical analysis to simulate the distribution of magnetic properties, iron loss and temperature of the transformer core model and a physical 110 kV single-phase autotransformer core. The maximum values of B, H and iron loss exist at the corners and T-joint of the core under rotating and DC-biased fields. The corresponding maximum value of the temperature increase is found in the main core limb area. The temperature rise of the 110 kV transformer core under various DC-biased conditions is measured and compared with the FEM (Finite Element Method) results of the proposed model and the model solely based on the magnetization curve B||H. The calculation error of the temperature rise obtained by the improved model is approximately 3.76-15.73% and is much less than the model solely based on magnetization curve B||H (approximately 50.71-66.92%).

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