104 research outputs found
Assessment of Cyfluthrin commercial formulation on growth, photosynthesis and catalase activity of green algae
Aquatic environments of the pampasic region of Argentina are severely affected by agricultural contamination due to an increase in a glyphosate tolerant transgenic variety of soybean crops. The present study is aimed to determine the effects of a commonly used Cyfluthrin commercial formulation (CCF) on growth, some physiological and biochemical parameter of four species of green algae. Significant inhibition of algal growth was observed from 0.1 mg Cyf/l. 96 h IC50 were between 0.92 and 4.85 mg Cyf/l. CCF caused algicidal effects. Photosynthesis was stimulated by 50% in Scenedesmus quadricauda cultures exposed to the lowest concentration (hormesis). Algal photosynthesis inhibition was observed at higher concentrations with IC50 values between 1.7 and 8.9 mg Cyf/l. Similar toxicity endpoints were found as a consequence of applying the traditional methodology of short-term chronic toxicity test of 96 h of exposition and the methodology developed using the Clark type photosynthetic oxygen evolution method. CAT activity was significantly increased between 23% and 33% considering the four species, at a lower concentration than those affecting algal growth and photosynthesis, indicating a potential biomarker. Taking into account that the extent of the soybean crops in the region is about fourteen million hectares, the improvement and extension of environmental tools for early detection of the action of pesticides on this essential group of organisms are discussed.Fil: Sáenz, MarÃa Elena. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Universidad Nacional de Luján; ArgentinaFil: Di Marzio, Walter Dario. Universidad Nacional de Luján; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Alberdi, José Luis. Universidad Nacional de Luján; Argentin
An orchestrated intron retention program in meiosis controls timely usage of transcripts during germ cell differentiation
Global transcriptome reprogramming during sper-matogenesis ensures timely expression of factors in each phase of male germ cell differentiation. Sper-matocytes and spermatids require particularly exten-sive reprogramming of gene expression to switch from mitosis to meiosis and to support gamete morphogenesis. Here, we uncovered an extensive alternative splicing program during this transmeiotic differentiation. Notably, intron retention was largely the most enriched pattern, with spermatocytes showing generally higher levels of retention compared with spermatids. Retained introns are characterized by weak splice sites and are enriched in genes with strong relevance for gamete func-tion. Meiotic intron-retaining transcripts (IRTs) were exclusively localized in the nucleus. However, differ-ently from other developmentally regulated IRTs, they are stable RNAs, showing longer half-life than properly spliced transcripts. Strikingly, fate-mapping experiments revealed that IRTs are recruited onto polyribosomes days after synthesis. These studies reveal an unexpected function for regulated intron retention in modulation of the timely expression of select transcripts during spermatogenesis
Cyto and genotoxicity of positive and negative coated Silica nano particles on Celomocytes of earthworms Eisenia fetida (Oligocheta, Annelida)
To understand and assess the effects of nanoparticles (NPs) on the environment, should be well established quantitatively the concentration-response relationships. Also relate the potential effects on selected variables of response with the exposure to sub-lethal levels of NPs. In this work, we describe the ecotoxicological evaluation of negative and positive coated silica NPs (Si-Nps) on coelomic cells from Eisenia fetida. The cytotoxicity of earthworm coelomocytes, expressed as LC50-1hour, was equal to 73.94 and 116.93 μg/mL for positive and negative Si-NPs, respectively. Genotoxicity were determined on the basis that the Si-NPs promote the generation of reactive oxygen species (ROS) once added on cell membranes, or entered in cells. In this case both types of NPs were genotoxics even at the lowest tested concentration equal to 1 μg/mL.Fil: Di Marzio, Walter Dario. Universidad Nacional de Luján. Departamento de Ciencias Básicas. Programa de Investigación en EcotoxicologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Curieses, Silvana Patricia. Universidad Nacional de Luján. Departamento de Ciencias Básicas. Programa de Investigación en EcotoxicologÃa; Argentina. Consejo Nacional de Investigaciones CientÃficas y Técnicas; ArgentinaFil: Alberdi, José Luis. Universidad Nacional de Luján. Departamento de Ciencias Básicas. Programa de Investigación en EcotoxicologÃa; ArgentinaFil: Sáenz, MarÃa Elena. Consejo Nacional de Investigaciones CientÃficas y Técnicas; Argentina. Universidad Nacional de Luján. Departamento de Ciencias Básicas. Programa de Investigación en EcotoxicologÃa; Argentin
A Neuron, Microglia, and Astrocyte Triple Co-culture Model to Study Alzheimer’s Disease
Glial cells are essential to understand Alzheimer's disease (AD) progression, given their role in neuroinflammation and neurodegeneration. There is a need for reliable and easy to manipulate models that allow studying the mechanisms behind neuron and glia communication. Currently available models such as co-cultures require complex methodologies and/or might not be affordable for all laboratories. With this in mind, we aimed to establish a straightforward in vitro setting with neurons and glial cells to study AD. We generated and optimized a 2D triple co-culture model with murine astrocytes, neurons and microglia, based on sequential seeding of each cell type. Immunofluorescence, western blot and ELISA techniques were used to characterize the effects of oligomeric Aβ (oAβ) in this model. We found that, in the triple co-culture, microglia increased the expression of anti-inflammatory marker Arginase I, and reduced pro-inflammatory iNOS and IL-1β, compared with microglia alone. Astrocytes reduced expression of pro-inflammatory A1 markers AMIGO2 and C3, and displayed a ramified morphology resembling physiological conditions. Anti-inflammatory marker TGF-β1 was also increased in the triple co-culture. Lastly, neurons increased post-synaptic markers, and developed more and longer branches than in individual primary cultures. Addition of oAβ in the triple co-culture reduced synaptic markers and increased CD11b in microglia, which are hallmarks of AD. Consequently, we developed a straightforward and reproducible triple co-cultured model, where cells resemble physiological conditions better than in individual primary cultures: microglia are less inflammatory, astrocytes are less reactive and neurons display a more mature morphology. Moreover, we are able to recapitulate Aβ-induced synaptic loss and CD11b increase. This model emerges as a powerful tool to study neurodegeneration and neuroinflammation in the context of AD and other neurodegenerative diseases.The authors acknowledge financial support by Basque Government (IT1203-19; ELKARTEK KK-2020/00034; PIBA_2016_1_0009; and PIBA_2020_1_0012), CIBERNED (CB06/0005/0076), MICINN (PID2019-109724RB-I00 and PID2019-108465RB-I00). CL and JZ-I were supported by Ph.D. Scholarships from the Tatiana Pérez de Guzmán el Bueno Foundation and Basque Government, respectively
Astrocytes in Alzheimer’s Disease: Pathological Significance and Molecular Pathways
Astrocytes perform a wide variety of essential functions defining normal operation of the nervous system and are active contributors to the pathogenesis of neurodegenerative disorders such as Alzheimer’s among others. Recent data provide compelling evidence that distinct astrocyte states are associated with specific stages of Alzheimer´s disease. The advent of transcriptomics technologies enables rapid progress in the characterisation of such pathological astrocyte states. In this review, we provide an overview of the origin, main functions, molecular and morphological features of astrocytes in physiological as well as pathological conditions related to Alzheimer´s disease. We will also explore the main roles of astrocytes in the pathogenesis of Alzheimer´s disease and summarize main transcriptional changes and altered molecular pathways observed in astrocytes during the course of the disease.This work was supported by the FEDER/Ministerio de Ciencia e Innovación—Agencia Estatal de Investigación grant RTI2018-101850-A-I00 to A.M.A. (Spain), and a start-up grant from the IKERBASQUE Basque Foundation of Science to A.M.A
Refining predictions of iberian plant distribution: lessons from p. nigra and p. sylvestris palaeoecological-based habitat suitability models
In recent years, challenged by the climate scenarios put forward by the IPCC and its potential impact on plant distribution, numerous predictive techniques -including the so called habitat suitability models (HSM)- have been developed. Yet, as the output of the different methods produces different distribution areas, developing validation tools are strong needs to reduce uncertainties. Focused in the Iberian Peninsula, we propose a palaeo-based method to increase the robustness of the HSM, by developing an ecological approach to understand the mismatches between the palaeoecological information and the projections of the HSMs. Here, we present the result of (1) investigating causal relationships between environmental variables and presence of Pinus sylvestris L. and P. nigra Arn. available from the 3rd Spanish Forest Inventory, (2) developing present and past presence-predictions through the MaxEnt model for 6 and 21 kyr BP, and (3) assessing these models through comparisons with biomized palaeoecological data available from the European Pollen Database for the Iberian Peninsula
RNA Localization and Local Translation in Glia in Neurological and Neurodegenerative Diseases: Lessons from Neurons
Cell polarity is crucial for almost every cell in our body to establish distinct structural and functional domains. Polarized cells have an asymmetrical morphology and therefore their proteins need to be asymmetrically distributed to support their function. Subcellular protein distribution is typically achieved by localization peptides within the protein sequence. However, protein delivery to distinct cellular compartments can rely, not only on the transport of the protein itself but also on the transport of the mRNA that is then translated at target sites. This phenomenon is known as local protein synthesis. Local protein synthesis relies on the transport of mRNAs to subcellular domains and their translation to proteins at target sites by the also localized translation machinery. Neurons and glia specially depend upon the accurate subcellular distribution of their proteome to fulfil their polarized functions. In this sense, local protein synthesis has revealed itself as a crucial mechanism that regulates proper protein homeostasis in subcellular compartments. Thus, deregulation of mRNA transport and/or of localized translation can lead to neurological and neurodegenerative diseases. Local translation has been more extensively studied in neurons than in glia. In this review article, we will summarize the state-of-the art research on local protein synthesis in neuronal function and dysfunction, and we will discuss the possibility that local translation in glia and deregulation thereof contributes to neurological and neurodegenerative diseases.This paper was partially funded by grants awarded to J.B. (MICINN grants SAF2016-76347-R, RYC-2016-19837 and PID2019-110721RB-I00; The Alzheimer’s Association grant AARG-19-618303) and E.A. (MICINN grant PID2019-108465RB-I00; Basque Government grant PIBA-2020-1-0012). M.B.-U. is a UPV/EHU fellow; A.G.-B. is a FPU (FPU17/04891) fellow; M.G. and A.d.l.C. are GV fellows
Effect of Heat Treatment on the Microstructure and Hardness of Ni-Based Alloy 718 in a Variable Thickness Geometry Deposited by Powder Fed Directed Energy Deposition
Feature addition to existing parts is a trending application for Directed Energy Deposition (DED) and can be used to add complex geometry features to basic forged geometries with the aim to reduce and simplify the number of processing steps as machining and assembling. However, the mechanical properties of as-deposited Inconel 718 fabricated by Powder-fed Directed Energy Deposition (Powder-fed DED) are far lower than the relevant specifications, making it necessary to apply different heat treatment with the purpose of improving deposited material performance. In addition, the effects of heat treatments in both variable thickness deposited geometry and forge substrate have not been studied. In this study, the effect of heat treatment within the Aerospace Materials Specifications (AMS) for cast and wrought Inconel 718 on the microstructure and hardness of both the Ni-Based Alloy 718 deposited geometry and substrate are analyzed in different parts of the geometry. The microstructure of all samples (as-deposited and heat-treated) is analyzed by Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometer (EDS), confirming the formation of aluminum oxides and titanium nitrides and carbonitrides in the deposited structure.This research was funded by the vice-counsel of technology, innovation and competitiveness of the Basque Government (Eusko Jaurlaritza) under the ELKARTEK Program, QUALYFAM and EDISON projects, grant number KK-2020/00042 and KK-2022/00070, respectively
Lesson from the habitat suitability models to evaluate the environmental of Pinus nigra Arnold and Pinus sylvesris L. in the Iberian Peninsula
PREDICT POTENTIAL DISTRIBUTION. Spatial and temporal evolution of the species under different climate scenarios. Generation of habitat suitability models (HSM) high degree of uncertainty and limitations. The importance of their validation has been stressed. In this work we discuss the present potential distribution of P. sylvestris and P. nigra in the Iberian Peninsula by using MaxEnt, and evaluate the influence of the different environmental variables. Our intention is to select a set of environmental variables that explains better their current distribution, to achieve the most accurate and reliable models. Then we project them to the past climatic conditions (21 to 0 kyrs BP), to evaluate the outputs with existing palaeo-ecological data
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