RESUMEN
Heavy metals can severely influence the mineralisation of organic pollutants in a compound-polluted environment. However, to date, no study has focused on the effects of heavy metals on the active organic pollutant-degrading microbial communities to understand the bioremediation mechanism. In this study, toluene was used as the model organic pollutant to explore the effects of soils with different levels of heavy metal pollution on organic contaminant degradation in the same area via stable isotope probing (SIP) and 16 S rRNA high-throughput sequencing. Heavy metals can seriously affect toluene biodegradation and regulate the abundance and diversity of microbial communities. SIP revealed a drastic difference in the community structure of active toluene degraders between the unpolluted and heavy metal-polluted soils. All SIP-identified degraders were assigned to nine bacterial classes, among which Alphaproteobacteria, Gammaproteobacteria, and Bacilli were shared by both treatments. Among all active degraders, Nitrospira, Nocardioides, Conexibacteraceae, and Singulisphaera were linked to toluene biodegradation for the first time. Notably, the type of active degrader and microbial diversity were strongly related to biodegradation efficiency, indicating their key role in toluene biodegradation. Overall, heavy metals can affect the microbial diversity and alter the functional microbial communities in soil, thereby influencing the removal efficiency of organic contaminants. Our findings provide novel insights into the biodegradation mechanism of organic pollutants in heavy metal-polluted soils and highlight the biodiversity of microbes involved in toluene biodegradation in compound-polluted environments.
Asunto(s)
Contaminantes Ambientales , Metales Pesados , Microbiota , Contaminantes del Suelo , Tolueno/metabolismo , Microbiología del Suelo , Suelo/química , Granjas , Bacterias/metabolismo , Biodegradación Ambiental , Contaminantes del Suelo/metabolismoRESUMEN
Metal-organic frameworks (MOFs), a novel type of porous crystalline material, have aroused widespread interest in lithium-ion batteries (LIBs). The design and preparation of MOF electrodes with a stable structure and excellent electrochemical performance are primary concerns for improving the capacity of LIBs. Among them, two-dimensional (2D) materials with larger specific surface areas, richer active sites, and higher aspect ratios have great potential. We adopted a facile approach to synthesize unique Co-MOF nanosheets with a 2D flaky morphology and a mesoporous structure. In addition, low-temperature calcination increases the specific surface area and improves the porosity to achieve mass transfer. Sample M2 delivers high specific capacities and long lives (1402.0 mA h g-1 after 100 cycles at 500 mA g-1 and 462.4 mA h g-1 after 300 cycles at 1.0 A g-1) when the calcination temperature is 200 °C. Significant improvements in the cycle life and stability are attributed to the 2D flaky structure of the M2 sample and the available low-temperature calcination activation, which provide a simple strategy for the fabrication of inexpensive and excellent anodes for LIBs.
RESUMEN
The synthesis and H3 receptor ligand of a new series of lactam derivatives are reported. The new compounds were evaluated in vitro in H3 and H1 receptor-binding assays. The structure-activity relationship led us to the promising derivative 2-methyl-7-(3-morpholinopropoxy)-3,4-dihydroisoquinolin-1(2H)-one (11). The compound with highest affinity and greatest selectivity were further profiled, In addition, compound 11 exerted dose-dependent anti-nociceptive effects in the formalin test. These characteristics suggested that the potent and selective compound 11 could be a potent candidate for pain treatment.
Asunto(s)
Lactamas/metabolismo , Neuralgia/tratamiento farmacológico , Receptores Histamínicos H3/metabolismo , Humanos , Ligandos , Estructura MolecularRESUMEN
In this study, a series of phenyl-1,2,4-oxadiazole derivatives were synthesized and evaluated for anti-allodynic activity. Structure-activity relationship studies identified 1-{4-[3-(2,4-dichlorophenyl)-1,2,4-oxadiazol-5-yl]butyl}piperidine (39) with excellent affinity for the σ1 receptor and selectivity for the σ2 receptor, with poor activity to other central nervous system neurotransmitter receptors and transporters associated with pain. Compound 39 exhibited dose-dependent efficacy in suppressing the formalin-induced flinching and attenuating mechanical allodynia in chronic constriction injury-induced neuropathic rats. These results suggest that compound 39 exerts potent antihyperalgesic activity and could be considered as a promising candidate for treating neuropathic pain.
Asunto(s)
Hiperalgesia/tratamiento farmacológico , Neuralgia/tratamiento farmacológico , Oxadiazoles/farmacología , Receptores sigma/antagonistas & inhibidores , Administración Oral , Animales , Relación Dosis-Respuesta a Droga , Cobayas , Ligandos , Masculino , Estructura Molecular , Oxadiazoles/síntesis química , Oxadiazoles/química , Ratas , Relación Estructura-Actividad , Receptor Sigma-1RESUMEN
Serotonergic innervation of the prefrontal cortex (PFC) modulates neuronal activity and PFC functions. However, the cellular mechanism for serotonergic modulation of neuronal excitability remains unclear. We performed patch-clamp recording at the axon of layer-5 pyramidal neurons in rodent PFC slices. We found surprisingly that the activation of 5-HT1A receptors selectively inhibits Na+ currents obtained at the axon initial segment (AIS) but not those at the axon trunk. In addition, Na+ channel subtype NaV1.2 but not NaV1.6 at the AIS is selectively modulated by 5-HT1A receptors. Further experiments revealed that the inhibitory effect is attributable to a depolarizing shift of the activation curve and a facilitation of slow inactivation of AIS Na+ currents. Consistently, dual somatic and axonal recording and simulation results demonstrate that the activation of 5-HT1A receptors could decrease the success rate of action potential (AP) backpropagation toward the somatodendritic compartments, enhancing the segregation of axonal and dendritic activities. Together, our results reveal a selective modulation of NaV1.2 distributed at the proximal AIS region and AP backpropagation by 5-HT1A receptors, suggesting a potential mechanism for serotonergic regulation of functional polarization in the dendro-axonal axis, synaptic plasticity and PFC functions.
Asunto(s)
Segmento Inicial del Axón/metabolismo , Corteza Prefrontal/metabolismo , Células Piramidales/metabolismo , Receptor de Serotonina 5-HT1A/metabolismo , Canales de Sodio/metabolismo , Animales , Ratones , Ratones Mutantes , Ratas , Ratas Sprague-DawleyRESUMEN
The brain is the most complex organ in the human body and the main component of the central nervous system. Because it lacks the ability of regeneration, age is a major risk factor for most common neurodegenerative diseases, which caused an irreversible cognitive impairment. It has been shown that the function of molecular chaperones, majorly heat shock proteins, was compromised and then causes the imbalance of protein homeostasis inside the cell, which is the most influential reason of brain aging. Here, in this review, we discuss the mechanisms underneath the impairment of heat shock protein function during brain aging, including transcriptional regulation, posttranslational modification, and communication across cells and organs.
Asunto(s)
Envejecimiento/genética , Proteínas HSP90 de Choque Térmico/genética , Enfermedades Neurodegenerativas/genética , Encéfalo , Humanos , Chaperonas Moleculares/genéticaRESUMEN
Passenger's optimal path choice is one of the prominent research topics in the field of railway passenger transport organization. More and more different train types are available, increasing path choices from departure to destination for travelers are unstoppable. However, travelers cannot avoid being confused when they hope to choose a perfect travel plan based on various travel time and cost constraints before departure. In this study, railway passenger travel network is constructed based on train timetable. Both the generalized cost function we developed and the residual train capacity are considered to be the foundation of path searching procedure. The railway passenger travel network topology is analyzed based on residual train capacity. Considering the total travel time, the total travel cost, and the total number of passengers, we propose an optimal path searching algorithm based on residual train capacity in railway passenger travel network. Finally, the rationale of the railway passenger travel network and the optimal path generation algorithm are verified positively by case study.
Asunto(s)
Modelos Teóricos , Vías Férreas/métodosRESUMEN
Electro-catalytic conversion of nitrate (NO3-) to ammonia (NH3) via the Nitrate Reduction to Ammonia (NORA) process represents a promising strategy for both ammonia synthesis and environmental remediation. Despite its potential, the efficiency of low-concentration NORA is often hindered by mass transfer limitations, competing byproducts (N2 and NO2-), and side reactions such as hydrogen evolution. This study introduces a novel pulsed electro-synthesis technique that alternates the potential to periodically accumulate and transform NO2- intermediates near a Cu2O@Pd electrode, enhancing the NORA process. Compared with that under potentiostatic conditions, the Cu2O@Pd electrodes exhibited a higher NORA activity under the optimized pulsed condition, where a NH3-N Faradaic efficiency (FE) of 81.2%, a yield rate of 1.08 mg h-1 cm-2 and a selectivity efficiency (SE) of 81.5%, were achieved. In-situ characterization revealed an enhancement mechanism characterized by optimized adsorption of the key *NO intermediate, followed by the hydrogenation path "*N â *NH â *NH2â *NH3". Further investigations indicated the electro-catalytic synergies between Pd sites and Cu species, where the Pd atoms were the reaction sites for the H adsorption while the Cu species were responsible for the NO3- activation. This research offers a novel insight into a method of enhancing low-concentration NORA.
RESUMEN
Surround suppression was initially identified as a phenomenon at the neural level in which stimuli outside the neuron's receptive field alone cannot activate responses but can modulate neural responses to stimuli covered inside the receptive field. Subsequent studies showed that surround suppression is not only a critical property of neurons across species and brain areas but also has been found in visual perceptions. More importantly, surround suppression varies across individuals and shows significant differences between normal controls and patients with certain mental disorders. Here, we combined results from related literature and summarized the findings derived from physiological and psychophysical evidence. We first outline the basic properties of surround suppression in the visual system and perceptions. Then, we mainly summarize the differences in perceptual surround suppression among different human subjects. Our review suggests that there is no consensus regarding whether the strength of perceptual surround suppression could be used as an effective index to distinguish particular populations. Then, we summarized the similar mechanisms for surround suppression and cognitive impairments to further explore the potential clinical applications of surround suppression. A clearer understanding of the mechanisms of surround suppression in neural responses and perceptions is necessary for facilitating its clinical applications.
RESUMEN
Aqueous zinc-iodine batteries (AZIBs) are highly appealing for energy requirements owing to their safety, cost-effectiveness, and scalability. However, the inadequate redox kinetics and severe shuttling effect of polyiodide ions impede their commercial viability. Herein, several Zn-MOF-derived porous carbon materials are designed, and the further preparation of iron-doped porous carbon (Fe-N-C, M9) with varied Fe doping contents is optimized based on a facile self-assembly/carbonization approach. M9, with atomic Fe coordinated to nitrogen atoms, is employed as an efficient cathode host for AZIBs. Functional modifications of porous carbon hosts involving the doping species and levels are investigated. The adsorption tests, in situ Raman spectroscopy, and in situ UV-vis results demonstrate the adsorption capability and charge-discharge mechanism for the iodine species. Furthermore, experimental findings and theoretical analyses have proven that the redox conversion of iodine is enhanced through a physicochemical confinement effect. This study offers basic principles for the strategic design of single-atom dispersed carbon as an iodine host for high-performance AZIBs. Flexible soft-pack battery and wearable microbattery applications also have implications for future long-life aqueous battery designs.
RESUMEN
Polymetallic phosphides exhibit favorable conductivities. A reasonable design of nano-metal-organic frame (MOF) composite morphologies and in situ introduction of polymetallic phosphides into the framework can effectively improve electrolyte penetration and rapid electron transfer. To address existing challenges, Ni, with a strong coordination ability with N, is introduced to partially replace Co in nano-Co-MOF composite. The hollow nanostructure is stabilized through CoNi bimetallic coordination and low-temperature controllable polymetallic phosphide generation rate. The Ni, Co, and P atoms, generated during reduction, effectively enhance electron transfer rate within the framework. X-ray absorption fine structure (XAFS) characterization results further confirm the existence of Ni-N, Ni-Ni, and Co-Co structures in the nanocomposite. The changes in each component during the charge-discharge process of the electrochemical reactions are investigated using in situ X-ray diffraction (XRD). Theoretical calculations further confirm that P can effectively improve conductivity. VZNPGC//MXene MSCs, constructed with active materials derived from the hollow nano MOF composites synthesized through the Ni2+ stabilization strategy, demonstrate a specific capacitance of 1184 mF cm-2, along with an energy density of 236.75 µWh cm-2 (power density of 0.14 mW cm-2). This approach introduces a new direction for the synthesis of highly conductive nano-MOF composites.
RESUMEN
The neocortex comprises six cortical layers that play a crucial role in information processing; however, it remains unclear whether laminar processing is consistent across all regions within a single cortex. In this study, we demonstrate diverse laminar response patterns in the primary visual cortex (V1) of three male macaque monkeys when exposed to visual stimuli at different spatial frequencies (SFs). These response patterns can be categorized into two groups. One group exhibit suppressed responses in the output layers for all SFs, while the other type shows amplified responses specifically at high SFs. Further analysis suggests that both magnocellular (M) and parvocellular (P) pathways contribute to the suppressive effect through feedforward mechanisms, whereas amplification is specific to local recurrent mechanisms within the parvocellular pathway. These findings highlight the non-uniform distribution of neural mechanisms involved in laminar processing and emphasize how pathway-specific amplification selectively enhances representations of high-SF information in primate V1.
Asunto(s)
Estimulación Luminosa , Corteza Visual Primaria , Vías Visuales , Animales , Masculino , Corteza Visual Primaria/fisiología , Vías Visuales/fisiología , Percepción Visual/fisiología , Corteza Visual/fisiología , Macaca mulattaRESUMEN
Metallic photonic lattices are promising in their application to plasmonic optical devices; however, scalable fabrication strategies are limited by sample size, response wavelength (mostly in the visible range), cost, and duration. This paper proposes a direct imprinting strategy to fabricate large-area metallic photonic lattices, which present a strong plasmonic response and broadband angle-resolved tuning properties in the infrared region. This simple fabrication strategy combines solution-synthesized Au nanoparticle colloid and imprinting technology, which does not require the use of photoresist or lithography. Thus, the feature size and response wavelength can exceed the limitations of the beam size and wave band, thereby offering the advantages of a low cost and high throughput.
RESUMEN
Sensing extracellular glucose, budding yeast switches from aerobic glycolysis to oxidative phosphorylation to adapt to environmental changes. During the conversion of metabolic mode, mitochondrial function and morphology change significantly. Mitochondria are the main supply factories of energy for various life activities in cells. However, the research on the signal pathways from glucose sensing to changes in mitochondrial function and morphology is still scarce and worthy of further exploration. In this study, we found that in addition to the known involvement of molecular chaperone Hsp82 in stress response during the conversion of metabolic mode, the phosphorylation status of Hsp82 at S485 residue regulates mitochondrial function and morphology to maintain mitochondrial homeostasis. The Hsp82S485A mutant that mimics dephosphorylation at S485 residue showed abnormal growth phenotypes related to mitochondrial defects, such as the petite phenotype, slow growth rates, and inability to use non-fermentable carbon sources. Further exploring the causes of growth defects, we found that the Hsp82S485A mutant caused mitochondrial dysfunction, including a decrease in cellular oxygen consumption rate, defects in mitochondrial electron transport chain, decreased mitochondrial membrane potential and complete loss of mtDNA. Furthermore, the Hsp82S485A mutant displayed fragmented or globular mitochondria, which may be responsible for its mitochondrial dysfunction. Our findings suggested that the phosphorylation status of Hsp82 at S485 residue might regulate mitochondrial function and morphology by affecting the stability of mitochondrial fission and fusion-related proteins. Thus, Hsp82 might be a key molecule in the signal pathway from glucose sensing to changes in mitochondrial function and morphology.
Asunto(s)
Glucosa , Proteínas HSP90 de Choque Térmico , Mitocondrias , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Glucosa/metabolismo , Homeostasis , Proteínas HSP90 de Choque Térmico/metabolismo , Mitocondrias/metabolismo , Fosforilación Oxidativa , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMEN
Introduction: Electron shuttles (ESs) play a key role in extracellular electron transfer (EET) in Shewanella oneidensis MR-1. However, the quantification relationship between ES concentration, biofilm formation, and biocurrent generation has not been clarified. Methods: In this study, 9,10-anthraquinone-2-sulfonic acid (AQS)-mediated EET and biofilm formation were evaluated at different AQS concentrations in bioelectrochemical systems (BESs) with S. oneidensis MR-1. Results and discussion: Both the biofilm biomass (9- to 17-fold) and biocurrent (21- to 80-fold) were substantially enhanced by exogenous AQS, suggesting the dual ability of AQS to promote both biofilm formation and electron shuttling. Nevertheless, biofilms barely grew without the addition of exogenous AQS, revealing that biofilm formation by S. oneidensis MR-1 is highly dependent on electron shuttling. The biofilm growth was delayed in a BES of 2,000 µM AQS, which is probably because the redundant AQS in the bulk solution acted as a soluble electron acceptor and delayed biofilm formation. In addition, the maximum biocurrent density in BESs with different concentrations of AQS was fitted to the Michaelis-Menten equation (R 2 = 0.97), demonstrating that microbial-catalyzed ES bio-reduction is the key limiting factor of the maximum biocurrent density in BESs. This study provided a fundamental understanding of ES-mediated EET, which could be beneficial for the enrichment of electroactive biofilms, the rapid start-up of microbial fuel cells (MFCs), and the design of BESs for wastewater treatment.
RESUMEN
The bioavailability of arsenic (As) is influenced by ammonium (NH4+-N) fertilization, but the underlying mechanisms controlling As transformation in soil-rice systems are still not fully understood. The effects of two NH4+-N fertilizers, urea and NH4HCO3, on the transformation of As in a paddy soil with low organic matter content and transfer in rice plants were investigated. Treatments with urea and NH4HCO3 significantly increased arsenite (As(III)) concentration in porewater, bioavailable As in rhizosphere soil, and the relative abundance of the As(V) respiratory reductase gene (arrA) and As(III) methyltransferase gene (arsM). Furthermore, the relative expression of As transporter genes in rice roots, such as OsLsi1, OsLsi2, and OsLsi3, was upregulated, and the translocation efficiency of As(III) from rice roots to brown rice was promoted. Subsequently, As(III) accumulation in brown rice significantly increased. Therefore, attention should be paid to As-contaminated paddy fields with NH4+-N fertilization.
Asunto(s)
Compuestos de Amonio , Arsénico , Oryza , Contaminantes del Suelo , Arsénico/metabolismo , Oryza/metabolismo , Compuestos de Amonio/metabolismo , Suelo , Raíces de Plantas/química , Urea/metabolismo , Contaminantes del Suelo/metabolismoRESUMEN
Current studies are ongoing to find new drugs for the treatment of hepatocellular carcinoma (HCC). The discovery of drugs depends on the identification of molecules that can play essential roles in the development of liver cancer, for example, Notch pathway molecules. γ-Secretase inhibitors (GSIs) can inhibit the cleavage of intramembranous substrates of all Notch receptors and subsequently suppress Notch signaling. However, whether the inhibition of the Notch pathway can suppress or promote HCC growth is still under debate. In this study, we examined the expression of Notch pathway molecules in 20 pairs of HCC tissue with their normal counterparts and a panel of eight HCC cell lines. We also determined the effects of different types of GSI treatments on the cell growth of those HCC cell lines. Our results showed that the molecules of the Notch pathway were expressed in six of the eight HCC cell lines. Those six HCC cell lines were more sensitive to GSI-I treatment than the nonexpression ones. Among the four inhibitors, GSI-X and GSI-XXI exerted no effect on HCC cells growth at all. GSI-IX inhibited the growth of four HCC cell lines at 40 µmol/l. In contrast, most of these HCC cell lines were susceptible to a low concentration of GSI-I (1.2 µmol/l) treatment. The suppressive effect of GSI-I on cell growth was because of the inhibition of C-Myc, a Notch target gene. In addition, 80% (16/20) of the specimens showed either an increased expression of at least one Notch receptor or an augmented expression of Jagged1 compared with their normal counterparts. Our study reports for the first time that different kinds of GSIs can block the growth of several HCC cell lines. Our finding suggests that GSI-I is a potential chemical reagent and warrants additional testing in liver cancer therapeutics.
Asunto(s)
Antineoplásicos/uso terapéutico , Carbamatos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Dipéptidos/uso terapéutico , Neoplasias Hepáticas/tratamiento farmacológico , Oligopéptidos/uso terapéutico , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/efectos de los fármacos , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Benzodiazepinonas/uso terapéutico , Proteínas de Unión al Calcio/efectos de los fármacos , Proteínas de Unión al Calcio/genética , Carcinoma Hepatocelular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Genes myc/efectos de los fármacos , Células Hep G2 , Proteínas de Homeodominio/efectos de los fármacos , Proteínas de Homeodominio/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Proteína Jagged-1 , Neoplasias Hepáticas/genética , Proteínas de la Membrana/efectos de los fármacos , Proteínas de la Membrana/genética , Receptores Notch/antagonistas & inhibidores , Receptores Notch/efectos de los fármacos , Receptores Notch/genética , Proteínas Serrate-Jagged , Factor de Transcripción HES-1RESUMEN
Understanding the relation between phase morphology and physical processes in polymer blends is the key to the fabrication of reproducible and reliable polymer optoelectronic devices. In this work, taking the advantage of low-temperature spectroscopy, we have observed the on-site generation of excitons and long-lived charges in different phase morphology polymer/fullerene blends. Probing at 10K, the photo-generated species are localized to where they are generated. We found that the generation of excitons and long-lived charges is highly influenced by the local molecular phase morphology. We further demonstrated that although the influence of phase morphology is localized to the place that excitons and long-lived charges are generated, this influence can persist over sub-millisecond timescales. Thus, we believe that the fate of excitons and long-lived charges is determined by the location at which they are generated, which can in turn be controlled precisely by molecular phase morphology.
RESUMEN
The feasibility of chemical stabilization-based strategy for extensive field application is under debate due to lacking a proper framework for its sustainability assessment during its life cycle. Herein, a comprehensive framework consisting of crop production, soil quality, and carbon footprint was constructed for assessing agricultural land remediation based on a two-year paddy field trial. Results show that between the two representative agents, biochar scenario substantially benefits for environmental, social, and agricultural sustainability, because of its more positive impacts on human health and ecosystem, public acceptance, soil reproductive, and rice yield. A notably higher sustainability score of 80.7 for biochar scenario than that of 47.0 for lime is found, in spite of the economical sustainability of lime. The net ecosystem carbon budget of the biochar scenario exhibits an unprecedentedly positive value of 17.8 t CO2-eq ha-1, which can finely contribute to a positive carbon budget during remediation. Our finding demonstrates that biochar strategy enables a multi-objective achievement of soil quality - crop production - carbon budget during agricultural land remediation. This study provides new insights into sustainability assessment for restoring agricultural land for safe crop production and synergizing with carbon neutral plan.
Asunto(s)
Oryza , Contaminantes del Suelo , Agricultura/métodos , Cadmio , Carbono , Carbón Orgánico , Ecosistema , Humanos , SueloRESUMEN
Spatial integration of visual information is an important function in the brain. However, neural computation for spatial integration in the visual cortex remains unclear. In this study, we recorded laminar responses in V1 of awake monkeys driven by visual stimuli with grating patches and annuli of different sizes. We find three important response properties related to spatial integration that are significantly different between input and output layers: neurons in output layers have stronger surround suppression, smaller receptive field (RF), and higher sensitivity to grating annuli partially covering their RFs. These interlaminar differences can be explained by a descriptive model composed of two global divisions (normalization) and a local subtraction. Our results suggest suppressions with cascaded normalizations (CNs) are essential for spatial integration and laminar processing in the visual cortex. Interestingly, the features of spatial integration in convolutional neural networks, especially in lower layers, are different from our findings in V1.