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PURPOSE: To optimize the design and demonstrate the integration of a helmet-shaped container filled with a high-permittivity material (HPM) slurry with RF head coil arrays to improve RF coil sensitivity and SNR for human-brain proton MRI. METHODS: RF reception magnetic fields ( B 1 - $$ {\mathrm{B}}_1^{-} $$ ) of a 32-channel receive-only coil array with various geometries and permittivity values of HPM slurry helmet are calculated with electromagnetic simulation at 7 T. A 16-channel transmit-only coil array, a 32-channel receive-only coil array, and a 2-piece HPM slurry helmet were constructed and assembled. RF transmission magnetic field ( B 1 + $$ {\mathrm{B}}_1^{+} $$ ), B 1 - $$ {\mathrm{B}}_1^{-} $$ , and MRI SNR maps from the entire human brain were measured and compared. RESULTS: Simulations showed that averaged B 1 - $$ {\mathrm{B}}_1^{-} $$ improvement with the HPM slurry helmet increased from 57% to 87% as the relative permittivity (εr) of HPM slurry increased from 110 to 210. In vivo experiments showed that the average B 1 + $$ {\mathrm{B}}_1^{+} $$ improvement over the human brain was 14.5% with the two-piece HPM slurry (εr ≈ 170) helmet, and the average B 1 - $$ {\mathrm{B}}_1^{-} $$ and SNR were improved 63% and 34%, respectively, because the MRI noise level was increased by the lossy HPM. CONCLUSION: The RF coil sensitivity and MRI SNR were largely improved with the two-piece HPM slurry helmet demonstrated by both electromagnetic simulations and in vivo human head experiments at 7 T. The findings demonstrate that incorporating an easily producible HPM slurry helmet into the RF coil array significantly enhances human-brain MRI SNR homogeneity and quality at ultrahigh field. Greater SNR improvement is anticipated using the less lossy HPM and optimal design.
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Acetochlor residues can contaminate anoxic habitats where anaerobic microbial transformation dominates. Herein, a highly efficient anaerobic acetochlor-degrading consortium ACT6 was enriched using sulfate and acetochlor as selection pressures. The acclimated consortium ACT6 showed an 8.7-fold increase in its ability to degrade acetochlor compared with the initial consortium ACT1. Two degradation pathways of acetochlor were found: reductive dechlorination and thiol-substitution dechlorination in the chloroacetyl group, in which the latter dominated. Acclimation enhanced the abundances of Desulfovibrio, Proteiniclasticum, and Lacrimispora from 0.7 to 28.0% (40-fold), 4.7 to 18.1% (4-fold), and 2.3 to 12.3% (5-fold), respectively, which were positively correlated with sulfate concentrations and acetochlor degradation ability. Three acetochlor-degrading anaerobes were isolated from the acclimated consortium ACT6, namely Cupidesulfovibrio sp. SRB-5, Proteiniclasticum sp. BAD-10, and Lacrimispora sp. BAD-7. This study provides new insights into the anaerobic catabolism of acetochlor and the anaerobic treatment of acetochlor in wastewater.
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Biodegradación Ambiental , Herbicidas , Sulfatos , Toluidinas , Herbicidas/metabolismo , Herbicidas/química , Toluidinas/metabolismo , Toluidinas/química , Anaerobiosis , Sulfatos/metabolismo , Sulfatos/química , Consorcios Microbianos , Halogenación , Bacterias/metabolismo , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificaciónRESUMEN
Background: Isoorientin (ISO), a flavone C-glycoside, is a glycogen synthase kinase 3ß (GSK3ß) substrate-competitive inhibitor. ISO has potential in treatment of Alzheimer's disease (AD). An excessive activation of GSK3ß can lead to neuroinflammation causing neuronal damage. Microglia cells, as resident immune cells of the central nervous system, mediate neuroinflammation. Here, we studied the effects of ISO on microglial activation to alleviate neuroinflammation.Methods: Effects of ISO were observed upon the stimulation of mouse microglia BV2 or SIM-A9 cells by lipopolysaccharide (LPS). Lithium chloride (LiCl) was the positive control as a GSK3ß inhibitor. The release of TNF-α and NO were analyzed by ELISA and Griess assays, while expressions of COX-2, Iba-1, BDNF, GSK3ß, NF-κB p65, IκB, Nrf2 and HO-1 were detected by Western blotting. In the co-culture model of SIM-A9 cells and differentiated SH-SY5Y human neuroblastoma cells, effects of ISO on microglia-mediated neuronal damage were evaluated with the MTS assay.Results: ISO significantly inhibited the production of TNF-α (p < 0.01), NO (p < 0.001) and the expression of COX-2 (p < 0.01) and Iba-1 (p < 0.05) induced by LPS, and increased BDNF. The cell viability of SH-SY5Y was inhibited by LPS in the co-culture, which was prevented by ISO pretreatment. ISO increased the expression of p-GSK3ß (Ser9), IκB and HO-1 in the cytoplasm, decreased NF-κB p65 and increased Nrf2 in the nucleus compared with the LPS group.Conclusion: ISO attenuated the activation of microglia through regulating the GSK3ß, NF-κB and Nrf2/HO-1 signaling pathways to exert neuroprotection.
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Ibuprofen, a widely used nonsteroidal anti-inflammatory drug, contaminates agricultural products and potentially threatens human health due to its frequent detection and poor biodegradability. Microbial metabolism dominates the elimination of residual ibuprofen in the environment. In mineral salt medium at pH 6 with 5 mM glucose, Streptomyces sp. D218 transformed ibuprofen concentrations ranging from 0.05 to 0.40 mM in 24 h. The optimal temperature, pH, and initial OD600â¯nm for ibuprofen transformation by strain D218 were 25-37 °C, 5.0-6.0, and 1.0-1.5, respectively. Strain D218 could simultaneously transform ibuprofen into the intermediates 2-hydroxyibuprofen and ibuprofen amide (IBUA). The two intermediates were further metabolized to 2-hydroxyibuprofen amide (2HIBUA), thus relieving the growth inhibition of ibuprofen in Scenedesmus obliquus. This is the first complete pathway reported for the detoxification of ibuprofen transformation by a Gram-positive strain. These findings further our understanding of the microbial catabolism of the IBU.
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Biotransformación , Ibuprofeno , Scenedesmus , Streptomyces , Ibuprofeno/metabolismo , Ibuprofeno/química , Streptomyces/metabolismo , Scenedesmus/metabolismo , Scenedesmus/crecimiento & desarrollo , Scenedesmus/química , Antiinflamatorios no Esteroideos/metabolismo , Antiinflamatorios no Esteroideos/química , Biodegradación AmbientalRESUMEN
Subjective cognitive decline (SCD) is a high-risk population in the preclinical stage of Alzheimer's disease (AD), and olfactory dysfunction is a risk factor for dementia progression. The present study aimed to explore the patterns of functional connectivity (FC) changes in the olfactory neural circuits during olfactory stimulation in SCD subjects. A total of 56 SCD subjects and 56 normal controls (NCs) were included. All subjects were assessed with a cognitive scale, an olfactory behavior test, and olfactory task-based functional magnetic resonance imaging scanning. The FC differences in olfactory neural circuits between the two groups were analyzed by the generalized psychophysiological interaction. Additionally, we calculated and compared the activation of brain regions within the olfactory neural circuits during odor stimulation, the volumetric differences in brain regions showing FC differences between groups, and the correlations between neuroimaging indicators and olfactory behavioral and cognitive scale scores. During odor stimulation, the FC between the bilateral primary olfactory cortex (bPOC) and the right hippocampus in the SCD group was significantly reduced; while the FC between the right hippocampus and the right frontal cortex was significantly increased in the SCD group. The bPOC of all subjects showed significant activation, but no significant difference in activation between groups was found. No significant differences were observed in the volume of the brain regions within the olfactory neural circuits or in olfactory behavior between groups. The volume of the bPOC and right frontal cortex was significantly positively correlated with olfactory identification, and the volume of the right frontal cortex and right hippocampus was significantly correlated with cognitive functions. Furthermore, a significant correlation between the activation of bPOC and the olfactory threshold was found in the whole cohort. These results suggested that while the structure of the olfactory neural circuits and olfactory behavior in SCD subjects remained stable, there were significant changes observed in the FC of the olfactory neural circuits (specifically, the POC-hippocampus-frontal cortex neural circuits) during odor stimulation. These findings highlight the potential of FC alterations as sensitive imaging markers for identifying high-risk individuals in the early stage of AD.
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Disfunción Cognitiva , Lóbulo Frontal , Hipocampo , Imagen por Resonancia Magnética , Corteza Olfatoria , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/fisiopatología , Disfunción Cognitiva/etiología , Corteza Olfatoria/diagnóstico por imagen , Corteza Olfatoria/fisiología , Corteza Olfatoria/fisiopatología , Hipocampo/diagnóstico por imagen , Hipocampo/fisiopatología , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/fisiopatología , Percepción Olfatoria/fisiología , Red Nerviosa/diagnóstico por imagen , Red Nerviosa/fisiopatología , Red Nerviosa/fisiología , Conectoma , OdorantesRESUMEN
Alzheimer's disease (AD) is a neurodegenerative disease mainly characterized by cognitive impairment. Glycogen synthase kinase 3 (GSK3ß) is a potential therapeutic target against AD. Isoorientin (ISO), a GSK3ß substrate competitive inhibitor, plays anti-AD effects in in vitro and in vivo AD model. TFGF-18 is an ISO synthetic analog with improved potency, but its neuroprotective effect in vivo remains to be elucidated, and the underlying mechanisms of GSK3ß inhibitor against AD need to be clarified. This study investigated the TFGF-18 and ISO effects on gut homeostasis and neuroinflammation in scopolamine (SCOP)-induced AD mice. And the protection on barrier function was observed in in vitro blood-brain barrier (BBB) model of mouse brain microvascular endothelial cells (bEnd.3). The results show that TFGF-18 and ISO improved cognitive function in SCOP-induced mice, and inhibited cholinergic system disorders and inflammation in the brain and intestine, decreased the level of lipopolysaccharides (LPS) in serum and intestine, protected the diversity and balance of intestinal microbiome, increased the expressions of tight junction protein (ZO-1, occludin), brain derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) in the mouse brain and intestine. In addition, TFGF-18 and ISO protected against barrier damage in LPS-stimulated BBB model of bEnd.3 cells in vitro. TFGF-18 and ISO increased the ratio of p-GSK3ß/GSK3ß, suppressed toll-like receptors 4 (TLR-4) expression and nuclear factor kappa-B (NF-κB) activation in vivo and in vitro, and increased the expressions of ß-catenin, nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in vitro. In conclusion, The GSK3ß inhibitors TFGF-18 and ISO modulate the gut homeostasis and barrier function to inhibit neuroinflammation and attenuate cognitive impairment by regulating NF-κB, ß-catenin and Nrf2/HO-1 pathways.
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Acute oral toxicity is currently not available for most polycyclic aromatic hydrocarbons (PAHs), especially their derivatives, because it is cost-prohibitive to experimentally determine all of them. Here, quantitative structure-activity relationship (QSAR) models using machine learning (ML) for predicting the toxicity of PAH derivatives were developed, based on oral toxicity data points of 788 individual substances of rats. Both the individual ML algorithm gradient boosting regression trees (GBRT) and the stacking ML algorithm (extreme gradient boosting + GBRT + random forest regression) provided the best prediction results with satisfactory determination coefficients for both cross-validation and the test set. It was found that those PAH derivatives with fewer polar hydrogens, more large-sized atoms, more branches, and lower polarizability have higher toxicity. Software based on the optimal ML-QSAR model was successfully developed to expand the application potential of the developed model, obtaining reliable prediction of pLD50 values and reference doses for 6893 external PAH derivatives. Among these chemicals, 472 were identified as moderately or highly toxic; 10 out of them had clear environment detection or use records. The findings provide valuable insights into the toxicity of PAHs and their derivatives, offering a standard platform for effectively evaluating chemical toxicity using ML-QSAR models.
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INTRODUCTION: Since the outbreak of COVID-19, microplastics (MPs) and triclosan in pharmaceuticals and personal care products (PPCPs) are markedly rising. MPs and triclosan are co-present in the environment, but their interactions and subsequent implications on the fate of triclosan in plants are not well understood. OBJECTIVE: This study aimed to investigate effects of charged polystyrene microplastics (PS-MPs) on the fate of triclosan in cabbage plants under a hydroponic system. METHODS: 14C-labeling method and liquid chromatography coupled with quadrupole/time-of-flight mass spectrometry (LC-QTOF-MS) analysis were applied to clarify the bioaccumulation, distribution, and metabolism of triclosan in hydroponics-cabbage system. The distribution of differentially charged PS-MPs in cabbage was investigated by confocal laser scanning microscopy and scanning electron microscopy. RESULTS: The results showed that MPs had a significant impact on bioaccumulation and metabolism of triclosan in hydroponics-cabbage system. PS-COO-, PS, and PS-NH3+ MPs decreased the bioaccumulation of triclosan in cabbage by 69.1 %, 81.5 %, and 87.7 %, respectively, in comparison with the non-MP treatment (control). PS-MPs also reduced the translocation of triclosan from the roots to the shoots in cabbage, with a reduction rate of 15.6 %, 28.3 %, and 65.8 % for PS-COO-, PS, and PS-NH3+, respectively. In addition, PS-NH3+ profoundly inhibited the triclosan metabolism pathways such as sulfonation, nitration, and nitrosation in the hydroponics-cabbage system. The above findings might be linked to strong adsorption between PS-NH3+ and triclosan, and PS-NH3+ may also potentially inhibit the growth of cabbage. Specially, the amount of triclosan adsorbed on PS-NH3+ was significantly greater than that on PS and PS-COO-. The cabbage biomass was reduced by 76.9 % in PS-NH3+ groups, in comparison with the control. CONCLUSION: The uptake and transformation of triclosan in hydroponics-cabbage system were significantly inhibited by charged PS-MPs, especially PS-NH3+. This provides new insights into the fate of triclosan and other PPCPs coexisted with microplastics for potential risk assessments.
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In planta expression of recombinant antibodies has been proposed as a strategy for herbicide resistance but is not well advanced yet. Here, an atrazine nanobody gene fused with a green fluorescent protein tag was transformed to Arabidopsis thaliana, which was confirmed with PCR, ELISA, and immunoblotting. High levels of nanobody accumulation were observed in the nucleus, cytoderm, and cytosol. The nanobody expressed in the plant had similar affinity, sensitivity, and selectivity as that expressed in Escherichia coli. The T3 homozygous line showed resistance in a dose-dependent manner up to 380 g ai/ha of atrazine, which is approximately one-third of the recommended field application rate. This is the first report of utilizing a nanobody in plants against herbicides. The results suggest that utilizing a high-affinity herbicide nanobody gene rather than increasing the expression of nanobodies in plants may be a technically viable approach to acquire commercial herbicide-resistant crops and could be a useful tool to study plant physiology.
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Arabidopsis , Atrazina , Resistencia a los Herbicidas , Herbicidas , Plantas Modificadas Genéticamente , Anticuerpos de Dominio Único , Atrazina/farmacología , Herbicidas/farmacología , Arabidopsis/genética , Arabidopsis/inmunología , Arabidopsis/metabolismo , Arabidopsis/efectos de los fármacos , Resistencia a los Herbicidas/genética , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/inmunología , Anticuerpos de Dominio Único/genética , Anticuerpos de Dominio Único/farmacología , Anticuerpos de Dominio Único/inmunologíaRESUMEN
Humans naturally integrate signals from the olfactory and intranasal trigeminal systems. A tight interplay has been demonstrated between these two systems, and yet the neural circuitry mediating olfactory-trigeminal (OT) integration remains poorly understood. Using functional magnetic resonance imaging (fMRI), combined with psychophysics, this study investigated the neural mechanisms underlying OT integration. Fifteen participants with normal olfactory function performed a localization task with air-puff stimuli, phenylethyl alcohol (PEA; rose odor), or a combination thereof while being scanned. The ability to localize PEA to either nostril was at chance. Yet, its presence significantly improved the localization accuracy of weak, but not strong, air-puffs, when both stimuli were delivered concurrently to the same nostril, but not when different nostrils received the two stimuli. This enhancement in localization accuracy, exemplifying the principles of spatial coincidence and inverse effectiveness in multisensory integration, was associated with multisensory integrative activity in the primary olfactory (POC), orbitofrontal (OFC), superior temporal (STC), inferior parietal (IPC) and cingulate cortices, and in the cerebellum. Multisensory enhancement in most of these regions correlated with behavioral multisensory enhancement, as did increases in connectivity between some of these regions. We interpret these findings as indicating that the POC is part of a distributed brain network mediating integration between the olfactory and trigeminal systems. PRACTITIONER POINTS: Psychophysical and neuroimaging study of olfactory-trigeminal (OT) integration. Behavior, cortical activity, and network connectivity show OT integration. OT integration obeys principles of inverse effectiveness and spatial coincidence. Behavioral and neural measures of OT integration are correlated.
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Mapeo Encefálico , Imagen por Resonancia Magnética , Corteza Olfatoria , Humanos , Masculino , Femenino , Adulto , Corteza Olfatoria/fisiología , Corteza Olfatoria/diagnóstico por imagen , Adulto Joven , Percepción Olfatoria/fisiología , Alcohol Feniletílico , Psicofísica , Nervio Trigémino/fisiología , Nervio Trigémino/diagnóstico por imagen , OdorantesRESUMEN
BACKGROUND: Alzheimer's disease (AD) is a neurodegenerative disease characterized by progressive cognitive deficits. Although the pathogenesis of AD is unclear, oxidative stress has been implicated to play a dominant role in its development. The flavonoid isoorientin (ISO) and its synthetic derivatives TFGF-18 selectively inhibit glycogen synthase kinase-3ß (GSK-3ß), a potential target of AD treatment. PURPOSE: To investigate the neuroprotective effect of TFGF-18 against oxidative stress via the GSK-3ß pathway in hydrogen peroxide (H2O2)-induced rat pheochromocytoma PC12 cells in vitro and scopolamine (SCOP)-induced AD mice in vivo. METHOD: The oxidative stress of PC12 cells was induced by H2O2 (600 µM) and the effects of TFGF-18 (2 and 8 µM) or ISO (12.5 and 50 µM) were observed. The AD mouse model was induced by SCOP (3 mg/kg), and the effects of TFGF-18 (2 and 8 mg/kg), ISO (50 mg/kg), and donepezil (DNP) (3 mg/kg) were observed. DNP, a currently accepted drug for AD was used as a positive control. The neuronal cell damages were analyzed by flow cytometry, LDH assay, JC-1 assay and Nissl staining. The oxidative stress was evaluated by the detection of MDA, SOD, GPx and ROS. The level of ACh, and the activity of AChE, ChAT were detected by the assay kit. The expressions of Bax, Bcl-2, caspase3, cleaved-caspase3, p-AKT (Thr308), AKT, p-GSK-3ß (Ser9), GSK-3ß, Nrf2, and HO-1, as well as p-CREB (Ser133), CREB, and BDNF were analyzed by western blotting. Morris water maze test was performed to analyze learning and memory ability. RESULTS: TFGF-18 inhibited neuronal damage and the expressions of Bax, caspase3 and cleaved-caspase3, and increased the expression of Bcl-2 in vitro and in vivo. The level of MDA and ROS were decreased while the activities of SOD and GPx were increased by TFGF-18. Moreover, TFGF-18 increased the p-AKT, p-GSK-3ß (Ser9), Nrf2, HO-1, p-CREB, and BDNF expression reduced by H2O2 and SCOP. Meanwhile, MK2206, an AKT inhibitor, reversed the effect of TFGF-18 on the AKT/GSK-3ß pathway. In addition, the cholinergic system (ACh, ChAT, and AChE) disorders were retrained and the learning and memory impairments were prevented by TFGF-18 in SCOP-induced AD mice. CONCLUSIONS: TFGF-18 protects against neuronal cell damage and cognitive impairment by inhibiting oxidative stress via AKT/GSK-3ß/Nrf2 pathway.
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Enfermedad de Alzheimer , Glucógeno Sintasa Quinasa 3 beta , Luteolina , Factor 2 Relacionado con NF-E2 , Estrés Oxidativo , Proteínas Proto-Oncogénicas c-akt , Escopolamina , Transducción de Señal , Animales , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratones , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/inducido químicamente , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/patología , Células PC12 , Escopolamina/toxicidad , Proteínas Proto-Oncogénicas c-akt/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Factor 2 Relacionado con NF-E2/metabolismo , Transducción de Señal/efectos de los fármacos , Masculino , Luteolina/farmacología , Luteolina/uso terapéutico , Modelos Animales de Enfermedad , Cognición/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéuticoRESUMEN
Lettuce is one of the most widely cultivated and consumed dicotyledonous vegetables globally. Despite the availability of its reference genome sequence, lettuce gene annotation remains incomplete, impeding comprehensive research and the broad application of genomic resources. Long-read RNA isoform sequencing (Iso-Seq) offers substantial advantages for analyzing RNA alternative splicing and aiding gene annotation, yet it faces throughput limitations. We present the HIT-ISOseq method tailored for bulk sample analysis, significantly enhancing RNA sequencing throughput on the PacBio platform by concatenating cDNA. Here we show, HIT-ISOseq generates 3-4 cDNA molecules per CCS read in lettuce, yielding 15.7 million long reads per PacBio Sequel II SMRT Cell 8 M. We validate its effectiveness in analyzing six lettuce tissue samples, including roots, stems, and leaves, revealing tissue-specific gene expression patterns and RNA isoforms. Leveraging diverse tissue long-read RNA sequencing, we refine the transcript annotation of the lettuce reference genome, expanding its GO and KEGG annotation repertoire. Collectively, this study serves as a foundational reference for genome annotation and the analysis of multi-sample isoform expression, utilizing high-throughput long-read transcriptome sequencing.
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Secuenciación de Nucleótidos de Alto Rendimiento , Lactuca , Análisis de Secuencia de ARN , Lactuca/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Análisis de Secuencia de ARN/métodos , ARN de Planta/genética , Especificidad de Órganos/genética , Regulación de la Expresión Génica de las Plantas , Anotación de Secuencia Molecular , Empalme Alternativo , Isoformas de ARN/genética , Genes de PlantasRESUMEN
Increasing use and release of graphene nanomaterials and pharmaceutical and personal care products (PPCPs) in soil environment have polluted the environment and posed high ecological risks. However, little is understood about the interactive effects and mechanism of graphene on the behaviors of PPCPs in soil. In the present study, the effects of reduced graphene oxide nanomaterials (RGO) on the fate of triclosan in two typical soils (S1: silty loam; S2: silty clay loam) were investigated with 14C-triclosan, high-resolution mass spectrometry, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), density functional theory (DFT) calculations, and microbial community structure analysis. The results showed that RGO prolonged the half-life of triclosan by 23.6-51.3 %, but delayed the formation of transformed products such as methyl triclosan and dechlorinated dimer of triclosan in the two typical soils. Mineralization of triclosan to 14CO2 was inhibited by 48.2-79.3 % in 500 mg kg-1 RGO in comparison with that in the control, whereas the bound residue was 54.2-56.4 % greater than the control. RGO also reduced the relative abundances of triclosan-degrading bacteria (Pseudomonas and Sphingomonas) in soils. Compared to silty loam, RGO more effectively inhibited triclosan degradation in silty clay loam. Furthermore, the DFT calculations suggested a strong association of the adsorption of triclosan on RGO with the van der Waals forces and π-π interactions. These results revealed that RGO inhibited the transformation of 14C-triclosan in soil through strong adsorption and triclosan-degrading bacteria inhibition in soils. Therefore, the presence of RGO may potentially enhance persistence of triclosan in soil. Overall, our study provides valuable insights into the risk assessment of triclosan in the presence of GNs in soil environment.
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Grafito , Nanoestructuras , Contaminantes del Suelo , Suelo , Triclosán , Grafito/química , Suelo/química , Microbiología del Suelo , Radioisótopos de CarbonoRESUMEN
Xanthates, common mining flotation reagents, strongly bind thiophilic metals such as copper (Cu), lead (Pb), cadmium (Cd), and zinc (Zn) and consequentially change their bioavailability and mobility upon their discharge into the environment. However, accurate quantification of the metal-xanthate complexes has remained elusive. This study develops a novel and robust method that realizes the accurate quantification of the metal-xanthate complexes resulted from single and multiple reactions of three typical xanthates (ethyl, isopropyl, and butyl xanthates) and four thiophilic metals (Cu, Pb, Cd, and Zn) in water samples. This method uses sulfur (S2-) dissociation, followed by tandem solid phase extraction of C18 + PWAX and subsequent LC-MS/MS analysis. It has a wide linearity range (1-1000 µg/L, R2 ≥ 0.995), low method detection limits (0.002-0.036 µg/L), and good recoveries (70.6-107.0 %) at 0.01-10 mg/L of xanthates. Applications of this method showed ubiquitous occurrence of the metal-xanthate complexes as the primary species in flotation wastewaters, which the concentrations were 4.6-28.9-fold higher than those previously determined. It is the first quantitative method established for the analysis of metal-xanthate complexes in water samples, which is of great importance to comprehensively understand the fate and risks of xanthates in the environment.
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Microcystins (MCs) have a significant influence on aquatic ecosystems, but little is known about their terrestrial fate and impact. Here, we investigated the fate of two MCs (MC-LR and MC-RR) in the soil-earthworm system, with consideration of their congener-specific impact on earthworm health, soil bacteria, and soil metabolome. Although MCs had little acute lethal effect on earthworms, they caused obvious growth inhibition and setae rupture. Relative to MC-RR, MC-LR exhibited higher bioaccumulation and the resulting dermal lesions and deformation of longitudinal muscles. While the incorporation of both MCs into soils stimulated pathogenic bacteria and depressed oxidative stress tolerant bacteria, the response among soil nitrification and glutathione metabolism differed between the two congeners. The dissipation kinetics of MCs obeyed the first-order model. Earthworms stimulated soil N-cycling enzyme activities, increased the abundance of MC-degrading bacteria, and promoted bacterial metabolic functions related to glutathione metabolism, xenobiotics biodegradation, and metabolism of amino acids that comprise MCs, which accelerated the dissipation of MC-LR and MC-RR by 227% and 82%, respectively. These results provide evidence of significant congener differences in the terrestrial fate and impact of MCs, which will enable a better understanding of their role in mediating soil functions and ecosystem services.
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Microcistinas , Oligoquetos , Microbiología del Suelo , Contaminantes del Suelo , Animales , Oligoquetos/metabolismo , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad , Microcistinas/metabolismo , Microcistinas/toxicidad , Suelo/química , Glutatión/metabolismo , Biodegradación Ambiental , Bacterias/metabolismo , BioacumulaciónRESUMEN
Cereals are the main source of energy in the human diet. Compared to refined grains, whole grains retain more beneficial components, including dietary fiber, polyphenols, proteins, vitamins, and minerals. Dietary fiber and bound polyphenols (biounavailable) in cereals are important active substances that can be metabolized by the gut microorganisms and affect the intestinal environment. There is a close relationship between the gut microbiota structures and various disease phenotypes, although the consistency of this link is affected by many factors, and the specific mechanisms are still unclear. Remodeling unfavorable microbiota is widely recognized as an important way to target the gut and improve diseases. This paper mainly reviews the interaction between the gut microbiota and cereal-derived dietary fiber and polyphenols, and also summarizes the changes to the gut microbiota and possible molecular mechanisms of related glycolipid metabolism. The exploration of single active ingredients in cereals and their synergistic health mechanisms will contribute to a better understanding of the health benefits of whole grains. It will further help promote healthier whole grain foods by cultivating new varieties with more potential and optimizing processing methods.
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Fibras de la Dieta , Microbioma Gastrointestinal , Polifenoles , Granos Enteros , Polifenoles/metabolismo , Fibras de la Dieta/metabolismo , Fibras de la Dieta/análisis , Humanos , Granos Enteros/química , Granos Enteros/metabolismo , Animales , Grano Comestible/químicaRESUMEN
BACKGROUND AND PURPOSE: Preferences can be developed for, or against, specific brands and services. Using two functional magnetic resonance imaging (fMRI) experiments, this study investigated two dissociable aspects of reward processing, craving and liking, in chocolate lovers. The goal was to further delineate the neural basis supporting branding effects using familiar chocolate (FC) and unfamiliar chocolate (UC) brand images. METHODS: In the first experiment, subjects rated their subjective craving and liking on a scale of 1-5 (weak-strong) for each FC and UC image. In the second experiment, they performed a choice task between FC and UC images. RESULTS: Both the craving and liking ratings were significantly greater for FC and were differentially correlated with choice behavior. Craving ratings predicted greater preference for UC, and liking ratings predicted greater preference for FC. A contrast of neural activity for UC versus FC choice trials revealed significantly greater activation for UC choices in the bilateral inferior frontal gyrus and right caudate head. Response times for the FC images were faster than UC images; fMRI activity in the ventromedial prefrontal cortex was significantly correlated with response times during FC trials, but not UC trials. These correlations were significantly different from each other at the group level. CONCLUSIONS: The choices for branded chocolate products are driven by higher subjective reward ratings and lower neural processing demands.
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Encéfalo , Chocolate , Preferencias Alimentarias , Imagen por Resonancia Magnética , Humanos , Femenino , Masculino , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/fisiología , Preferencias Alimentarias/fisiología , Mapeo Encefálico/métodos , Adulto Joven , Conducta de Elección/fisiologíaRESUMEN
The maize (Zea mays L.) glycosyltransferase family 1 comprises many uridine diphosphate glycosyltransferase (UGT) members. However, UGT activities and biochemical functions have seldom been revealed. In this study, the genes of two flavonoid di-O-glycosyltransferases ZmUGT84A1 and ZmUGT84A2 were cloned from maize plant and expressed in Escherichia coli. Phylogenetic analysis showed that the two enzymes were homologous to AtUGT84A1 and AtUGT84A3. The two recombinant enzymes showed a high conversion rate of luteolin to its glucosides, mainly 4',7-di-O-glucoside and minorly 3',7-di-O-glucoside in two-step glycosylation reactions in vitro. Moreover, the recombinant ZmUGT84A1 and ZmUGT84A2 had a broad substrate spectrum, converting eriodictyol, naringenin, apigenin, quercetin, and kaempferol to monoglucosides and diglucosides. The highly efficient ZmUGT84A1 and ZmUGT84A2 may be used as a tool for the effective synthesis of various flavonoid O-glycosides and as markers for crop breeding to increase O-glycosyl flavonoid content in food.
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Flavonoides , Glicosiltransferasas , Flavonoides/química , Glicosiltransferasas/metabolismo , Zea mays/genética , Zea mays/metabolismo , Filogenia , Fitomejoramiento , Glicósidos , Glucósidos/metabolismo , Clonación MolecularRESUMEN
Alzheimer's disease (AD) is a prevalent form of dementia that affects an estimated 32 million individuals globally. Identifying early indicators is vital for screening at-risk populations and implementing timely interventions. At present, there is an urgent need for early and sensitive biomarkers to screen individuals at risk of AD. Among all sensory biomarkers, olfaction is currently one of the most promising indicators for AD. Olfactory dysfunction signifies a decline in the ability to detect, identify, or remember odors. Within the spectrum of AD, impairment in olfactory identification precedes detectable cognitive impairments, including mild cognitive impairment (MCI) and even the stage of subjective cognitive decline (SCD), by several years. Olfactory impairment is closely linked to the clinical symptoms and neuropathological biomarkers of AD, accompanied by significant structural and functional abnormalities in the brain. Olfactory behavior examination can subjectively evaluate the abilities of olfactory identification, threshold, and discrimination. Olfactory functional magnetic resonance imaging (fMRI) can provide a relatively objective assessment of olfactory capabilities, with the potential to become a promising tool for exploring the neural mechanisms of olfactory damage in AD. Here, we provide a timely review of recent literature on the characteristics, neuropathology, and examination of olfactory dysfunction in the AD continuum. We focus on the early changes in olfactory indicators detected by behavioral and fMRI assessments and discuss the potential of these techniques in MCI and preclinical AD. Despite the challenges and limitations of existing research, olfactory dysfunction has demonstrated its value in assessing neurodegenerative diseases and may serve as an early indicator of AD in the future.
RESUMEN
Neonicotinoids (NEOs), a large class of organic compounds, are a type of commonly used pesticide for crop protection. Their uptake and accumulation in plants are prerequisites for their intra- and intercellular movements, transformation, and function. Understanding the molecular mechanisms that underpin NEO uptake by plants is crucial for effective application, which remains elusive. Here, we demonstrate that NEOs enter plant cells primarily through the transmembrane symplastic pathway and accumulate mainly in the cytosol. Two plasma membrane intrinsic proteins discovered in Brassica rapa, BraPIP1;1 and BraPIP2;1, were found to encode aquaporins (AQPs) that are highly permeable to NEOs in different plant species and facilitate NEO subcellular diffusion and accumulation. Their conserved transport function was further demonstrated in Xenopus laevis oocyte and yeast assays. BraPIP1;1 and BraPIP2;1 gene knockouts and interaction assays suggested that their proteins can form functional heterotetramers. Assessment of the potential of mean force indicated a negative correlation between NEO uptake and the energy barrier of BraPIP1;1 channels. This study shows that AQPs transport organic compounds with greater osmolarity than previously thought, providing new insight into the molecular mechanisms of organic compound uptake and facilitating innovations in systemic pesticides.