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The nanomaterialprotein "corona" is a dynamic entity providing a syntheticnatural interface mediating cellular uptake and subcellular distribution of nanomaterials in biological systems. As nanomaterials are central to the safe-by-design of future nanomedicines and the practice of nanosafety, understanding and delineating the biological and toxicological signatures of the ubiquitous nanomaterialprotein corona are precursors to the continued development of nanobio science and engineering. However, despite well over a decade of extensive research, the dynamics of intracellular release or exchange of the blood protein corona from nanomaterials following their cellular internalization remains unclear, and the biological footprints of the nanoparticleprotein corona traversing cellular compartments are even less well understood. To address this crucial bottleneck, the current work screened evolution of the intracellular protein corona along the endocytotic pathway from blood via lysosomes to cytoplasm in cancer cells. Intercellular proteins, including pyruvate kinase M2 (PKM2), and chaperones, displaced some of the initially adsorbed blood proteins from the nanoparticle surface, which perturbed proteostasis and subsequently incited chaperone-mediated autophagy (CMA) to disrupt the key cellular metabolism pathway, including glycolysis and lipid metabolism. Since proteostasis is key to the sustainability of cell function, its collapse and the resulting CMA overdrive spell subsequent cell death and aging. Our findings shed light on the consequences of the transport of extracellular proteins by nanoparticles on cell metabolism.
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Nanoestruturas , Coroa de Proteína , Coroa de Proteína/metabolismo , Proteômica , Proteostase , Piruvato Quinase/metabolismoRESUMO
Research on plant-nanomaterial interactions has greatly advanced over the past decade. One particularly fascinating discovery encompasses the immunomodulatory effects in plants. Due to the low doses needed and the comparatively low toxicity of many nanomaterials, nanoenabled immunomodulation is environmentally and economically promising for agriculture. It may reduce environmental costs associated with excessive use of chemical pesticides and fertilizers, which can lead to soil and water pollution. Furthermore, nanoenabled strategies can enhance plant resilience against various biotic and abiotic stresses, contributing to the sustainability of agricultural ecosystems and the reduction of crop losses due to environmental factors. While nanoparticle immunomodulatory effects are relatively well-known in animals, they are still to be understood in plants. Here, we provide our perspective on the general components of the plant's immune system, including the signaling pathways, networks, and molecules of relevance for plant nanomodulation. We discuss the recent scientific progress in nanoenabled immunomodulation and nanopriming and lay out key avenues to use plant immunomodulation for agriculture. Reactive oxygen species (ROS), the mitogen-activated protein kinase (MAPK) cascade, and the calcium-dependent protein kinase (CDPK or CPK) pathway are of particular interest due to their interconnected function and significance in the response to biotic and abiotic stress. Additionally, we underscore that understanding the plant hormone salicylic acid is vital for nanoenabled applications to induce systemic acquired resistance. It is suggested that a multidisciplinary approach, incorporating environmental impact assessments and focusing on scalability, can expedite the realization of enhanced crop yields through nanotechnology while fostering a healthier environment.
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Agricultura , Nanoestruturas , Imunidade VegetalRESUMO
Molybdenum disulfide (nano-MoS2) nanomaterials have shown great potential for biomedical and catalytic applications due to their unique enzyme-mimicking properties. However, their potential agricultural applications have been largely unexplored. A key factor prior to the application of nano-MoS2 in agriculture is understanding its behavior in a complex soil-plant system, particularly in terms of its transformation. Here, we investigate the distribution and transformation of two types of nano-MoS2 (MoS2 nanoparticles and MoS2 nanosheets) in a soil-soybean system through a combination of synchrotron radiation-based X-ray absorption near-edge spectroscopy (XANES) and single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS). We found that MoS2 nanoparticles (NPs) transform dynamically in soil and plant tissues, releasing molybdenum (Mo) and sulfur (S) that can be incorporated gradually into the key enzymes involved in nitrogen metabolism and the antioxidant system, while the rest remain intact and act as nanozymes. Notably, there is 247.9 mg/kg of organic Mo in the nodule, while there is only 49.9 mg/kg of MoS2 NPs. This study demonstrates that it is the transformation that leads to the multifunctionality of MoS2, which can improve the biological nitrogen fixation (BNF) and growth. Therefore, MoS2 NPs enable a 30% increase in yield compared to the traditional molybdenum fertilizer (Na2MoO4). Excessive transformation of MoS2 nanosheets (NS) leads to the overaccumulation of Mo and sulfate in the plant, which damages the nodule function and yield. The study highlights the importance of understanding the transformation of nanomaterials for agricultural applications in future studies.
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Nanoestruturas , Solo , Solo/química , Glycine max , Molibdênio , AgriculturaRESUMO
The aggregation and limited activity of nanoscale zero-valent iron (NZVI) in aqueous media hinder its practical application. In this study, a cost-effective, environmentally friendly, robust, and efficient synthesis method for NZVI-based composite was developed. NZVI@Chitin-modified ZSM-5 (NZVI@C-ZSM) composite was facilely and greenly synthesized by loading NZVI into alkali-modified ZSM-5 molecular sieves after modifying with chitin as a surfactant and binder. NZVI@C-ZSM exhibited remarkable efficacy in TC removal, achieving a removal efficiency of 97.72% within 60 min. Compared with pristine NZVI, NZVI@C-ZSM demonstrated twice the removal efficiency, indicating that NZVI@C-ZSM effectively improved the dispersion and stability of NZVI. This enhancement provided more reactive sites for generating reactive oxygen species (ROS), significantly boosting catalytic activity and durability while reducing the potential risk of secondary pollution. An improved two-parameter pseudo-first-order kinetic model was used to effectively characterize the reaction kinetics. The mechanism for TC removal primarily involved an adsorption process and chemical oxidation-reduction reactions induced by hydroxyl radicals (â¢OH) and superoxide radicals (â¢O2-). Three potential degradation pathways for TC were suggested. Furthermore, NZVI@C-ZSM exhibited good resistance to interference, suggesting its broad potential for practical applications in complex environmental conditions. This study offers a viable material and method for addressing the issue of antibiotic-contaminated water, with potential applications in water resource management.
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Quitina , Ferro , Oxirredução , Tetraciclina , Poluentes Químicos da Água , Quitina/química , Poluentes Químicos da Água/química , Ferro/química , Tetraciclina/química , Química Verde/métodos , Antibacterianos/química , Zeolitas/químicaRESUMO
Understanding the potential of nanomaterials (NMs) to cross the blood-brain barrier (BBB), as a function of their physicochemical properties and subsequent behavior, fate, and adverse effect beyond that point, is vital for evaluating the neurological effects arising from their unintentional entry into the brain, which is yet to be fully explored. This is not only due to the complex nature of the brain but also the existing analytical limitations for characterization and quantification of NMs in the complex brain environment. By using a fit-for-purpose analytical workflow and an in vitro BBB model, we show that the physiochemical properties of metallic NMs influence their biotransformation in biological matrices, which in turn modulates the transport form, efficiency, amounts, and pathways of NMs through the BBB and, consequently, their neurotoxicity. The data presented here will support in silico modeling and prediction of the neurotoxicity of NMs and facilitate the tailored design of safe NMs.
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Barreira Hematoencefálica/metabolismo , Metais/química , Nanoestruturas/química , Astrócitos/metabolismo , Biotransformação , Encéfalo/irrigação sanguínea , Células Endoteliais/metabolismo , Exocitose , Humanos , Microvasos/citologia , Modelos Biológicos , Permeabilidade , TranscitoseRESUMO
CH4 emissions from inland waters are highly uncertain in the current global CH4 budget, especially for streams, rivers, and other lotic systems. Previous studies have attributed the strong spatiotemporal heterogeneity of riverine CH4 to environmental factors such as sediment type, water level, temperature, or particulate organic carbon abundance through correlation analysis. However, a mechanistic understanding of the basis for such heterogeneity is lacking. Here, we combine sediment CH4 data from the Hanford reach of the Columbia River with a biogeochemical-transport model to show that vertical hydrologic exchange flows (VHEFs), driven by the difference between river stage and groundwater level, determine CH4 flux at the sediment-water interface. CH4 fluxes show a nonlinear relationship with the magnitude of VHEFs, where high VHEFs introduce O2 into riverbed sediments, which inhibit CH4 production and induce CH4 oxidation, and low VHEFs cause transient reduction in CH4 flux (relative to production) due to reduced advective CH4 transport. In addition, VHEFs lead to the hysteresis of temperature rise and CH4 emissions because high river discharge caused by snowmelt in spring leads to strong downwelling flow that offsets increasing CH4 production with temperature rise. Our findings reveal how the interplay between in-stream hydrologic flux besides fluvial-wetland connectivity and microbial metabolic pathways that compete with methanogenic pathways can produce complex patterns in CH4 production and emission in riverbed alluvial sediments.
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Carbono , Metano , Metano/análise , Rios , Agricultura , Água , Dióxido de Carbono/análiseRESUMO
Nickel (Ni) is a trace element beneficial for plant growth and development and could improve crop yield by stimulating urea decomposition and nitrogen-fixing enzyme activity. A full life cycle study was conducted to compare the long-term effects of soil-applied NiO nanoparticles (n-NiO), NiO bulk (b-NiO), and NiSO4 at 10-200 mg kg-1 on plant growth and nutritional content of soybean. n-NiO at 50 mg kg-1 significantly promoted the seed yield by 39%. Only 50 mg kg-1 n-NiO promoted total fatty acid content and starch content by 28 and 19%, respectively. The increased yield and nutrition could be attributed to the regulatory effects of n-NiO, including photosynthesis, mineral homeostasis, phytohormone, and nitrogen metabolism. Furthermore, n-NiO maintained a Ni2+ supply for more extended periods than NiSO4, reducing potential phytotoxicity concerns. Single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) for the first time confirmed that the majority of the Ni in seeds is in ionic form, with only 28-34% as n-NiO. These findings deepen our understanding of the potential of nanoscale and non-nanoscale Ni to accumulate and translocate in soybean, as well as the long-term fate of these materials in agricultural soils as a strategy for nanoenabled agriculture.
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Nanopartículas , Níquel , Níquel/química , Glycine max , Nitrogênio , SoloRESUMO
Microplastics (MPs) have been widely detected in the world's water, which may pose a significant threat to the ecosystem as a whole and have been a subject of much attention because their presence impacts seas, lakes, rivers, and even the Polar Regions. There have been numerous studies that report direct adverse effects on marine organisms, but only a few have explored their ecological effects on freshwater organisms. In this field, there is still a lack of a systematic overview of the toxic effects and mechanisms of MPs on aquatic organisms, as well as a consistent understanding of the potential ecological consequences. This review describes the fate and impact on marine and freshwater aquatic organisms. Further, we examine the toxicology of MPs in order to uncover the relationship between aquatic organism responses to MPs and ecological disorders. In addition, an overview of the factors that may affect the toxicity effects of MPs on aquatic organisms was presented along with a brief examination of their identification and characterization. MPs were discussed in terms of their physicochemical properties in relation to their toxicological concerns regarding their bioavailability and environmental impact. This paper focuses on the progress of the toxicological studies of MPs on aquatic organisms (bacteria, algae, Daphnia, and fish, etc.) of different trophic levels, and explores its toxic mechanism, such as behavioral alternations, metabolism disorders, immune response, and poses a threat to the composition and stability of the ecosystem. We also review the main factors affecting the toxicity of MPs to aquatic organisms, including direct factors (polymer types, sizes, shapes, surface chemistry, etc.) and indirect factors (persistent organic pollutants, heavy metal ions, additives, and monomer, etc.), and the future research trends of MPs ecotoxicology are also pointed out. The findings of this study will be helpful in guiding future marine and freshwater rubbish studies and management strategies.
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Microplásticos , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Plásticos/toxicidade , Ecotoxicologia , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Organismos Aquáticos , Lagos , Monitoramento AmbientalRESUMO
The aquatic system is a major sink for engineered nanomaterials released into the environment. Here, we assessed the toxicity of graphene oxide (GO) using the freshwater planarian Dugesia japonica, an invertebrate model that has been widely used for studying the effects of toxins on tissue regeneration and neuronal development. GO not only impaired the growth of normal (homeostatic) worms, but also inhibited the regeneration processes of regenerating (amputated) worms, with LC10 values of 9.86 mg/L and 9.32 mg/L for the 48-h acute toxicity test, respectively. High concentration (200 mg/L) of GO killed all the worms after 3 (regenerating) or 4 (homeostasis) days of exposure. Whole-mount in situ hybridization (WISH) and immunofluorescence analyses suggest GO impaired stem cell proliferation and differentiation, and subsequently caused cell apoptosis and oxidative DNA damage during planarian regeneration. Mechanistic analysis suggests that GO disturbed the antioxidative system (enzymatic and non-enzymatic) and energy metabolism in the planarian at both molecular and genetic levels, thus causing reactive oxygen species (ROS) over accumulation and oxidative damage, including oxidative DNA damage, loss of mitochondrial membrane integrity, lack of energy supply for cell differentiation and proliferation leading to retardance of neuron regeneration. The intrinsic oxidative potential of GO contributes to the GO-induced toxicity in planarians. These data suggest that GO in aquatic systems can cause oxidative stress and neurotoxicity in planarians. Overall, regenerated tissues are more sensitive to GO toxicity than homeostatic ones, suggesting that careful handling and appropriate decisions are needed in the application of GO to achieve healing and tissue regeneration.
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Planárias , Animais , Planárias/genética , Homeostase/fisiologia , Apoptose , Oxirredução , Água DoceRESUMO
The smallest fraction of plastic pollution, submicron plastics (SMPs <1 µm) are expected to be ubiquitous in the environment. No information is available about SMPs in peatlands, which have a key role in sequestering carbon in terrestrial ecosystems. It is unknown how these plastic particles might behave and interact with (micro)organisms in these ecosystems. Here, we show that the chemical composition of polystyrene (PS) and poly(vinyl chloride) (PVC)-SMPs influenced their adsorption to peat. Consequently, this influenced the accumualtion of SMPs by Sphagnum moss and the composition and diversity of the microbial communities in peatland. Natural organic matter (NOM), which adsorbs from the surrounding water to the surface of SMPs, decreased the adsorption of the particles to peat and their accumulation by Sphagnum moss. However, the presence of NOM on SMPs significantly altered the bacterial community structure compared to SMPs without NOM. Our findings show that peatland ecosystems can potentially adsorb plastic particles. This can not only impact mosses themselves but also change the local microbial communities.
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Microbiota , Sphagnopsida , Sphagnopsida/química , Sphagnopsida/microbiologia , Solo/química , Adsorção , Plásticos , BactériasRESUMO
This study compared the impact and uptake of root-administered CeO2 nanoparticles (NPs) in rice growing under flooded and aerobic soil conditions, which are two water regimes commonly used for rice cultivation. CeO2 NPs at 100 mg/kg improved photosynthesis and plant growth by reducing the oxidative damage and enhancing plant tolerance to stress, while a higher concentration (500 mg/kg) of CeO2 NPs negatively affected plant growth. More significant effects were observed under the flooded condition than under the aerobic condition. CeO2 NPs of 100 and 500 mg/kg resulted in 78% and 70% higher accumulation of Ce in shoots under the flooded condition compared to the aerobic condition. CeO2 NPs partially transformed to Ce(III) species in soils and plants under both conditions. A higher extent of transformation under the flooded condition, which was partly attributed to the lower soil pH and redox potential under the flooded condition, leads to higher plant uptake of Ce. A higher extent of transformation in rhizosphere soil was observed. A higher plant transpiration rate (TR) under flooded conditions resulted in a higher accumulation of CeO2 species in shoots. This study, for the first time, reported that water regimes influenced the biotransformation of CeO2 NPs and their uptake and impact in rice plants.
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Cério , Nanopartículas , Oryza , Poluentes do Solo , Cério/toxicidade , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidadeRESUMO
Association of nanoparticles (NPs) with algae likely plays a critical role in their transfer in aquatic food chains. Although our understanding of the ecotoxicity and fate of NPs in the environment is increasing, it is still unclear how the physicochemical properties of NPs influence their interaction with algae at cellular levels and how this is reflected at a population level. This is due to the limitation in the existing analytical techniques to quantify the association of NPs with cells. To fill this data gap, we applied the novel technique of single-cell inductively coupled plasma mass spectrometry to quantify the cellular association of gold (Au)-NPs with algal cells (Pseudokirchneriella subcapitata) as a function of particle size, shape (spherical 10 nm, spherical 60 nm, spherical 100 nm, rod-shaped 10 × 40 nm, and rod-shaped 50 × 100 nm), and surface chemistry [citrate and natural organic matter (NOM) coating] on a cell-by-cell basis. The association of Au-NPs with algal cells was found to be a random probability following a so-called stochastic process; after 72 h of exposure, less than 45% of the cell population accumulated NPs on their surface. The number of Au-NPs per cell was found to be heterogeneously distributed as some cells were associated with a significantly higher number (e.g. up to 600 spherical 10 nm particles per cell) of Au-NPs than other cells present in the medium. The presence of NOM on the surface of the particles decreased the percentage of cells containing NPs except for the spherical 60 nm Au-NPs. We conclude that some algae within a population can accumulate NPs on their surface and this accumulation is influenced by the size, shape, and surface chemistry of NPs. It is important to understand how NPs may enter aquatic food chains to assess the possible risk.
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Engineered nanomaterials (ENMs) have huge potential for improving use efficiency of agrochemicals, crop production, and soil health; however, the behavior and fate of ENMs and the potential for negative long-term impacts to agroecosystems remain largely unknown. In particular, there is a lack of clear understanding of the transformation of ENMs in both soil and plant compartments. The transformation can be physical, chemical, and/or biological, and may occur in soil, at the plant interface, and/or inside the plant. Due to these highly dynamic processes, ENMs may acquire new properties distinct from their original profile; as such, the behavior, fate, and biological effects may also differ significantly. Several essential questions in terms of ENMs transformation are discussed, including the drivers and locations of ENM transformation in the soil-plant system and the effects of ENM transformation on analyte uptake, translocation, and toxicity. The main knowledge gaps in this area are highlighted and future research needs are outlined so as to ensure sustainable nanoenabled agricultural applications.
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Produtos Agrícolas , Inocuidade dos Alimentos , Nanoestruturas , Solo , Agricultura/normas , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/metabolismo , Nanoestruturas/química , Nanoestruturas/toxicidade , Solo/químicaRESUMO
A new ternary Mo-SnO2-graphite composite has been constructed via hydrothermal and ball milling. The Mo/SnO2 hybrids were homogeneously dispersed in graphite nanosheets. In the Mo-SnO2-graphite, Mo can inhibit the Sn nanoparticle aggregation, enhance the reversible conversion reaction in lithiation, and improve the electrochemical performance. Consequently, the Mo-SnO2-graphite composite contributes a high capacity of 1317.4 mAh g-1 at 0.2 A g-1 after 200 cycles, remarkable rate property of 514.0 mAh g-1 at 5 A g-1, and long-term cyclic stabilization of 759.0 mAh g-1 after 950 cycles at 1.0 A g-1. With outstanding electrochemical performance and facial synthesis, the ternary Mo-SnO2-graphite is a hopeful anode material for lithium-ion batteries (LIBs).
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The mechanism of graphene-based nanomaterial (GBM)-induced phytotoxicity and its association with the GBM physicochemical properties are not yet fully understood. The present study compared the effects of graphene oxide (GO) and reduced GO (rGO) on rice seedling growth under hydroponic conditions for 3 weeks. GO at 100 and 250 mg/L reduced shoot biomass (by 25 and 34%, respectively) and shoot elongation (by 17 and 43%, respectively) and caused oxidative damage, while rGO exhibited no overt effect except for the enhancement of the antioxidant enzyme activities, suggesting that the surface oxygen content is a critical factor affecting the biological impacts of GBMs. GO treatments (100 and 250 mg/L) enhanced the iron (Fe) translocation and caused excessive Fe accumulation in shoots (2.2 and 3.6 times higher than control), which was found to be the main reason for the oxidative damage in shoots. GO-induced acidification of the nutrient solution was the main driver for the Fe overload in plants. In addition to the antioxidant regulators, the plants triggered other pathways to defend against the Fe toxicity via downregulation of the Fe transport associated metabolites (mainly coumarins and flavonoids). Plant root exudates facilitated the reduction of toxic GO to nontoxic rGO, acting as another route for plant adaption to GO-induced phytotoxicity. This study provides new insights into the mechanism of the phytotoxicity of GBMs. It also provides implications for the agricultural application of GBM that the impacts of GBMs on the uptake of multiple nutrients in plants should be assessed simultaneously and reduced forms of GBMs are preferential to avoid toxicity.
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Grafite , Sobrecarga de Ferro , Nanoestruturas , Oryza , Poluentes do Solo , Humanos , Concentração de Íons de Hidrogênio , Estresse Oxidativo , Raízes de Plantas , PlântulaRESUMO
Pedestrian trajectory prediction under crowded circumstances is a challenging problem owing to human interaction and the complexity of the trajectory pattern. Various methods have been proposed for solving this problem, ranging from traditional Bayesian analysis to Social Force model and deep learning methods. However, most existing models heavily depend on specific scenarios because the trajectory model is constructed in absolute coordinates even though the motion trajectory as well as human interaction are in relative motion. In this study, a novel trajectory prediction model is proposed to capture the relative motion of pedestrians in extremely crowded scenarios. Trajectory sequences and human interaction are first represented with relative motion and then integrated to our model to predict pedestrians' trajectories. The proposed model is based on Long Short Term Memory (LSTM) structure and consists of an encoder and a decoder which are trained by truncated back propagation. In addition, an anisotropic neighborhood setting is proposed instead of traditional neighborhood analysis. The proposed approach is validated using trajectory data acquired at an extremely crowded train station in Tokyo, Japan. The trajectory prediction experiments demonstrated that the proposed method outperforms existing methods and is stable for predictions of varying length even when the model is trained with a controlled short trajectory sequence.
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Modelos Teóricos , Pedestres , Teorema de Bayes , Aprendizado Profundo , Humanos , JapãoRESUMO
We have shown that acupuncture, including manual and electroacupuncture (MA and EA), at the P5-6 acupoints stimulates afferent fibers in the median nerve (MN) to modulate sympathoexcitatory cardiovascular reflexes through central regulation of autonomic function. However, the mechanisms underlying acupuncture activation of these sensory afferent nerves and their cell bodies in the dorsal root ganglia (DRG) are unclear. Transient receptor potential vanilloid type 1 (TRPV1) is present in sensory nerve fibers distributed in the general region of acupoints like ST36 and BL 40 located in the hindlimb. However, the contribution of TRPV1 to activation of sensory nerves by acupuncture, leading to modulation of pressor responses, has not been studied. We hypothesized that TRPV1 participates in acupuncture's activation of sensory afferents and their associated cell bodies in the DRG to modulate pressor reflexes. Local injection of iodoresiniferatoxin (Iodo-RTX; a selective TRPV1 antagonist), but not 5% DMSO (vehicle), into the P6 acupoint on the forelimb reversed the MA's inhibition of pressor reflexes induced by gastric distension (GD). Conversely, inhibition of GD-induced sympathoexcitatory responses by EA at P5-6 was unchanged after administration of Iodo-RTX into P5-6. Single-unit activity of Group III or IV bimodal afferents sensitive to both mechanical and capsaicin stimuli responded to MA stimulation at P6. MA-evoked activity was attenuated significantly ( P < 0.05) by local administration of Iodo-RTX ( n = 12) but not by 5% DMSO ( n = 12) into the region of the P6 acupoint in rats. Administration of Iodo-RTX into P5-6 did not reduce bimodal afferent activity evoked by EA stimulation ( n = 8). Finally, MA at P6 and EA at P5-6 induced phosphorylation of extracellular signal-regulated kinases (ERK; an intracellular signaling messenger involved in cellular excitation) in DRG neurons located at C7-8 spinal levels receiving MN inputs. After TRPV1 was knocked down in the DRG at these spinal levels with intrathecal injection of TRPV1-siRNA, expression of phosphorylated ERK in the DRG neuron was reduced in MA-treated, but not EA-treated animals. These data suggest that TRPV1 in Group III and IV bimodal sensory afferent nerves contributes to acupuncture inhibition of reflex increases in blood pressure and specifically plays an important role during MA but not EA.
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Pontos de Acupuntura , Terapia por Acupuntura/métodos , Sistema Cardiovascular/inervação , Eletroacupuntura , Gânglios Espinais/metabolismo , Nervo Mediano/fisiologia , Reflexo , Canais de Cátion TRPV/metabolismo , Animais , Pressão Sanguínea , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Masculino , Inibição Neural , Fosforilação , Ratos Sprague-DawleyRESUMO
Acetylcholinesterase (AChE, EC 3.1.1.7) is a classical biomarker for monitoring contamination and intoxication of organophosphate (OP) and carbamate pesticides. In addition to these classical environmental AChE inhibitors, other organic toxic substances have been found to alter AChE activity in various species. These emerging organic AChE disruptors include certain persistent organic pollutants (POPs), polycyclic aromatic hydrocarbons (PAHs), and wildly used chemicals, most of which have received considerable public health concern in recent years. It is necessary to re-evaluate the environmental significances of AChE in terms of these toxic substances. Therefore, the present review is aiming to summarize correlations of AChE activity of certain organisms with the level of the contaminants in particular habitats, disruptions of AChE activity upon treatment with the emerging disruptors in vivo and in vitro, and action mechanisms underlying the effects on AChE. Over 40 chemicals belonging to six main categories were reviewed, including 12 POPs listed in the Stockholm Convention. AChE activity in certain organisms has been found to be well correlated with the contamination level of certain persistent pesticides and PAHs in particular habitats. Moreover, it has been documented that most of the listed toxic chemicals could inhibit AChE activity in diverse species ranging from invertebrates to mammals. Besides directly inactivating AChE, the mechanisms in terms of interference with the biosynthesis have been recognized for some emerging AChE disruptors, particularly for dioxins. The collected evidence suggests that AChE could serve as a potential biomarker for a diverse spectrum of organic environmental pollutants.
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Poluentes Ambientais , Praguicidas , Poluentes Químicos da Água , Acetilcolinesterase , Animais , Biomarcadores , Monitoramento AmbientalRESUMO
In this study, we present the Ensemble Convolutional Neural Network (ECNN), an elaborate CNN frame formulated based on ensembling state-of-the-art CNN models, to identify village buildings from open high-resolution remote sensing (HRRS) images. First, to optimize and mine the capability of CNN for village mapping and to ensure compatibility with our classification targets, a few state-of-the-art models were carefully optimized and enhanced based on a series of rigorous analyses and evaluations. Second, rather than directly implementing building identification by using these models, we exploited most of their advantages by ensembling their feature extractor parts into a stronger model called ECNN based on the multiscale feature learning method. Finally, the generated ECNN was applied to a pixel-level classification frame to implement object identification. The proposed method can serve as a viable tool for village building identification with high accuracy and efficiency. The experimental results obtained from the test area in Savannakhet province, Laos, prove that the proposed ECNN model significantly outperforms existing methods, improving overall accuracy from 96.64% to 99.26%, and kappa from 0.57 to 0.86.
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Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by overproduction of numerous autoantibodies. Many studies have sought to identify such biomarkers to distinguish patients with active lupus nephritis from SLE patients without renal involvement. Because antibodies to complement C1q appear to be prevalent in patients with active lupus nephritis, we analyzed the frequency of antigenic epitopes of C1q and their clinical significance in a large multicenter study of Chinese patients. The lupus cohort consisted of 210 patients with active lupus nephritis as a discovery cohort, 130 active patients as a validation cohort along with 130 SLE patients without clinical renal involvement, and 100 healthy controls. Serum antibodies to intact C1q, the collagen-like region, the globular head region, and the new linear A08 epitope to C1q were screened by specific ELISA. The frequency of antibodies to intact C1q, the C1q-collagen-like region, and the A08 antibodies in the discovery cohort were significantly higher than that in patients without renal involvement or healthy controls. Antibodies to the globular head region were not prevalent enough for further study. The results were confirmed in the validation cohort. The area under the curve for anti-A08 antibodies was significantly greater than those for both the intact and collagen-like region antibodies to discriminate between active lupus nephritis and active SLE without clinical renal involvement. The A08 antibodies were all negative at remission. The serum A08 antibody level correlated better with disease relapse than that of antibodies to either the intact or the collagen-like region, significantly predicting renal prognosis. Thus, serum levels of A08 C1q antibodies are closely associated with disease activity and prognosis in lupus nephritis.