Regulation of CD47 expression by interferon-gamma under chronic Methamphetamine exposure Title

Exposure to methamphetamine (Meth), a highly addictive widely used psychostimulant, is classically associated with damage to neuronal terminals, but its neurotoxicity can also be mediated via activation of the neuroinflammatory response. Microglia, the resident immune cells of the brain, become highly activated and increase the release of proinflammatory mediators upon exposure to Meth. However, their role in Meth-associated neurotoxicity is still not sufficiently understood. Data from our lab shows that, in the hippocampus, chronic Meth administration leads to microglia homeostasis dysregulation, synapse dysregulation, and downregulation of cluster-differentiation 47 protein (CD47). The crosstalk between CD47 and its receptor, signal regulatory protein α (SIRPα), is an important “don’t eat me signal” that inhibits phagocytosis. CD47 has been shown to protect synapses from excessive microglia-mediated pruning during development and neurodegeneration. Of note, in cancer cells CD47 expression is modulated by interferon-gamma (IFN-γ). Consistently, after chronic Meth, we observed a significant decrease of meningeal T cells, and a decrease in the production of IFN-y by these cells. Here we aim to clarify if IFNγ is regulating CD47 in the brain after chronic Meth administration, and consequently regulating synaptic pruning, using IFNyKO mice and wild-type mice injected with recombinant IFNy via stereotaxic surgery. Preliminary results indicate that IFNy/CD47 does not modulate microglia morphology and number after chronic Meth in the hippocampus. Currently we are evaluating synapses and phagocytosis, and we further expect to clarify the impact of IFNγ /CD47 in the chronic Meth conditioning and in memory.info:eu-repo/semantics/publishedVersio

Deciphering the astrocytic and synaptic changes under chronic alcohol exposure using a self-administration paradigm

Drug abuse is characterized by a compulsive and persistent drug-seeking behaviour, despite the harmful emotional, physical and social consequences. Our laboratory has previously found that the neuronal-glial crosstalk is critical in relaying the changes caused by acute exposure to psychoactive drugs through neuroimmune mechanisms. We have also reported that microglia can engulf postsynaptic components in the prefrontal cortex (PFC) of mice after repeated alcohol exposure and this led to increased anxiety in mice. The adverse effects of alcohol on the central nervous system (CNS) are well described, with astrocytes becoming reactive and displaying changes in gene expression, activity and proliferation. However, the mechanisms involved are not yet fully understood. We are currently characterizing the astrocytic response under chronic alcohol consumption, taking into account the crucial interaction between neuronal and glial cells in the development and maintenance of addiction. Using a well-established voluntary alcohol drinking paradigm, we are evaluating alcohol-associated changes in PFC astrocytes, synapses and their behavioural correlates. Our preliminary results indicate similar alcohol consumption patterns between males and females, however, males, but not females, present altered weight gain and experience a significant increase in inhibitory synapse density after chronic exposure to ethanol when compared to the control group. Our work is contributing to a better understanding of the impact of chronic alcohol intake and may lead to the development of new strategies for pharmacological intervention in drug addiction, based on the targets identified as critical for the neuronal-glial crosstalk.info:eu-repo/semantics/publishedVersio

Neuron-Microglia Contact-Dependent Mechanisms Attenuate Methamphetamine-Induced Microglia Reactivity and Enhance Neuronal Plasticity

Exposure to methamphetamine (Meth) has been classically associated with damage to neuronal terminals. However, it is now becoming clear that addiction may also result from the interplay between glial cells and neurons. Recently, we demonstrated that binge Meth administration promotes microgliosis and microglia pro-inflammation via astrocytic glutamate release in a TNF/IP(3)R2-Ca2+-dependent manner. Here, we investigated the contribution of neuronal cells to this process. As the crosstalk between microglia and neurons may occur by contact-dependent and/or contact-independent mechanisms, we developed co-cultures of primary neurons and microglia in microfluidic devices to investigate how their interaction affects Meth-induced microglia activation. Our results show that neurons exposed to Meth do not activate microglia in a cell-autonomous way but require astrocyte mediation. Importantly, we found that neurons can partially prevent Meth-induced microglia activation via astrocytes, which seems to be achieved by increasing arginase 1 expression and strengthening the CD200/CD200r pathway. We also observed an increase in synaptic individual area, as determined by co-localization of pre- and post-synaptic markers. The present study provides evidence that contact-dependent mechanisms between neurons and microglia can attenuate pro-inflammatory events such as Meth-induced microglia activation

Microglial Rac1 is essential for experience-dependent brain plasticity and cognitive performance

Microglia, the largest population of brain immune cells, continuously interact with synapses to maintain brain homeostasis. In this study, we use conditional cell-specific gene targeting in mice with multi-omics approaches and demonstrate that the RhoGTPase Rac1 is an essential requirement for microglia to sense and interpret the brain microenvironment. This is crucial for microglia-synapse crosstalk that drives experience-dependent plasticity, a fundamental brain property impaired in several neuropsychiatric disorders. Phosphoproteomics profiling detects a large modulation of RhoGTPase signaling, predominantly of Rac1, in microglia of mice exposed to an environmental enrichment protocol known to induce experience-dependent brain plasticity and cognitive performance. Ablation of microglial Rac1 affects pathways involved in microglia-synapse communication, disrupts experience-dependent synaptic remodeling, and blocks the gains in learning, memory, and sociability induced by environmental enrichment. Our results reveal microglial Rac1 as a central regulator of pathways involved in the microglia-synapse crosstalk required for experience-dependent synaptic plasticity and cognitive performance.info:eu-repo/semantics/publishedVersio

Microglia dysfunction caused by the loss of Rhoa disrupts neuronal physiology and leads to neurodegeneration

© 2020 The Author(s). Creative Commons Attribution (CC BY 4.0)Nervous tissue homeostasis requires the regulation of microglia activity. Using conditional gene targeting in mice, we demonstrate that genetic ablation of the small GTPase Rhoa in adult microglia is sufficient to trigger spontaneous microglia activation, producing a neurological phenotype (including synapse and neuron loss, impairment of long-term potentiation [LTP], formation of β-amyloid plaques, and memory deficits). Mechanistically, loss of Rhoa in microglia triggers Src activation and Src-mediated tumor necrosis factor (TNF) production, leading to excitotoxic glutamate secretion. Inhibiting Src in microglia Rhoa-deficient mice attenuates microglia dysregulation and the ensuing neurological phenotype. We also find that the Rhoa/Src signaling pathway is disrupted in microglia of the APP/PS1 mouse model of Alzheimer disease and that low doses of Aβ oligomers trigger microglia neurotoxic polarization through the disruption of Rhoa-to-Src signaling. Overall, our results indicate that disturbing Rho GTPase signaling in microglia can directly cause neurodegeneration.The authors acknowledge the support of the following i3S Scientific Platforms: Animal Facility, Translational Cytometry Unit (TraCy), BioSciences Screening (BS) and Advanced Light Microscopy (ALM), and members of the national infrastructure PPBI-Portuguese Platform of BioImaging (supported by POCI-01–0145-FEDER-022122). FCT Portugal ( PTDC/MED-NEU/31318/2017-031318 ) supported work in the J.B.R. lab. FCT Portugal , PEst ( UID/NEU/04539/2013 ), COMPETE-FEDER ( POCI-01-0145-FEDER-007440 ), Centro 2020 Regional Operational Programme ( CENTRO-01-0145-FEDER-000008 : BrainHealth 2020), and Strategic Project UIDB/04539/2020 and UIDP/04539/2020 (CIBB) supported work in the A.F.A. lab. C.C.P. and R.S. hold employment contracts financed by national funds through FCT (Fundação para a Ciência e a Tecnologia, I.P.) in the context of the program contract described in paragraphs 4, 5, and 6 of article 23 of law no. 57/2016, of August 29th, as amended by law no. 57/2017 of July 19th.info:eu-repo/semantics/publishedVersio

Caracterização molecular dos doentes portugueses com miocardiopatia dilatada

Introduction: Dilated cardiomyopathy (DCM) is a disease of the heart muscle characterized by ventricular dilatation and impaired systolic function. Familial forms account for 30-50% of cases. Autosomal dominant inheritance is the predominant pattern of transmission. Causal genetic variants have been identified in several genes and molecular diagnosis has implications for genetic counseling and risk stratification. Objective: We aimed to estimate the frequency of genetic variants and the molecular basis of DCM in Portugal. Methods: We performed a multicenter study of unrelated patients, recruited between 2013 and 2014. Variants in 15 genes were screened using PCR with direct sequencing (next-generation sequencing with at least 30-fold coverage combined with Sanger sequencing). Results: A total of 107 patients were included, 64 (60%) men, mean age at diagnosis 38±13 years, with 48 (45%) familial cases. In total, 31 rare variants in eight genes (mainly in MYBPC3, TNNT2 and LMNA) were identified, in 28 patients (26%). Only four variants had been previously described in association with DCM, 11 with hypertrophic cardiomyopathy, and nine variants were novel. Four variants were likely pathogenic and the remainder were of uncertain significance. We found no major differences in the main clinical and imaging characteristics between patients with or without rare variants and patients with likely pathogenic variants. Conclusions: Our results reflect the complexity and diversity of DCM genetics. For better inter-pretation of the pathogenicity of the variants found and their causative roles in DCM, molecularcascade screening of families is imperative. Further insight into genotype-phenotype correla-tions and risk stratification is desirable.Introdução: A miocardiopatia dilatada (MCD) é uma doença do músculo cardíaco caracterizada por dilatação ventricular e compromisso da função sistólica. As formas familiares são responsáveis por 30 a 50% dos casos. O padrão de hereditariedade predominante é o autossómicodominante. Variantes genéticas causais foram identificadas em vários genes e o diagnósticomolecular tem implicac¸ões para o aconselhamento genético e estratificação de risco.Objetivo: Avaliar a base molecular da MCD em Portugal.Métodos: Estudo multicêntrico de doentes não relacionados, recrutados entre 2013 e 2014.Foram analisados 15 genes, através da técnica de PCR com sequenciac¸ão direta (NGS com pelomenos uma cobertura de 30 vezes combinada com sequenciac¸ão de Sanger).Resultados: Foram incluídos 107 pacientes, 64 (60%) homens, idade média ao diagnóstico de38 ± 13 anos, com 48 (45%) casos familiares. Foram identificadas 31 variantes raras, em oitogenes, (principalmente MYBPC3, TNNT2 e LMNA) em 28 pacientes (26%). Apenas quatro variantestinham sido previamente descritas em associac¸ão com MCD, 11 com miocardiopatia hipertró-fica e nove variantes eram novas. Quatro variantes foram classificadas como provavelmentepatogénicas e as restantes de significado incerto. Não encontrámos diferenc¸as significativas nasprincipais características clínicas e imagiológicas entre doentes com ou sem variantes raras e doentes com variantes provavelmente patogénicas. Conclusões: Estes resultados refletem a complexidade e diversidade genética da MCD. Para uma melhor interpretação da patogenicidade das variantes e potencial causalidade, o rastreio molecular das famílias é imperativo. Uma visão mais aprofundada das correlações genótipo-fenótipo e da estratificação de risco é desejável

La democracia desde los márgenes : transformaciones en el campo político boliviano

Uno de los rasgos característicos de la política es que se trata de una cuestión de sujetos y, en consecuencia, de la existencia de una pluralidad de sujetos. Este libro preparado por el equipo dirigido por Marité Zegada es el mapeo y reconstrucción analítica más amplios que se han hecho sobre esta diversidad de espacios, de sujetos y de instituciones políticas que existen en el país, sobre todo para los últimos años. Ésta es la virtud más general de este trabajo: pensar la política dando cuenta de la pluralidad. Por un lado, hace un mapeo de espacios,fuerzas e instituciones pero no lo hace de una manera meramente descriptiva, sino que lo hace a través de una reconstrucción analítica que va revisando el tipo de discursos, de estrategias, es decir, de prácticas e ideas políticas que despliega cada uno de estos sujetos.Índice Prólogo 5 Introducción 9 1 Capítulo i 15 Elementos para (re)pensar el campo político boliviano: poder, política y democracia Algunas consideraciones históricas sobre la democracia 19 Lecturas de la democracia y la crisis de sus paradigmas 20 Nuevas articulaciones conceptuales de la democracia 22 Discursos y contenido de la democracia 25 Capítulo ii 29 Campos de conflicto: la crisis del Estado y su reconfiguración Elementos estructurales de la crisis estatal 29 La emergencia de nuevos elementos constitutivos del campo político 39 Campos de conflicto y dinámica sociopolítica en el gobierno de Evo Morales 44 Capítulo iii 99 ¿Qué cambió en el campo político boliviano? Un nuevo andamiaje constitucional Propuestas de las organizaciones sociales, indígenas y partidos políticos 99 Forma o carácter del Estado 100 Tipo de gobierno, modelo de democracia y régimen político 104 Poderes u órganos del Estado 106 Sistema de representación política 113 Análisis comparativo de la Constitución de 1967 y la de 2009 116 Capítulo iv 141 La democracia boliviana y sus (re)significaciones Estado Plurinacional y democracia 143 La autonomía: una estrategia de democratización del poder 151 Democracia participativa y democracia representativa en la nueva Constitución 155 La democracia comunitaria como forma de ejercicio del poder 164 Capítulo v 199 Movimientos sociales y nuevas formas de articulación de la política Movimientos sociales en el campo político 200 Viejos y nuevos sujetos políticos 206 Nuevas estrategias y repertorios de acción política 233 Capítulo vi 243 El gobierno de los movimiento sociales: una nueva práctica política-estatal Conformación de gobierno 243 Procesos de toma de decisiones 249 Mandar obedeciendo o los dos cerebros 254 Política y pragmatismo entre el sueño y la oportunidad 256 El mito del gobierno de los movimientos sociales 270 Discursos ideológicos y procesos de auto identificación 285 Evo es como yo: indigenismo, nacionalismo y socialismo Riesgos y potencialidades en el derrotero del gobierno 297 Conclusiones 303 Bibliografía 323 Anexos 33

Perception of Nursing Activities That Contribute to the Quality of Care: Validity and Reliability Testing of the French Version

Background and purpose: Measuring nurses' perceptions of the activities contributing to the quality of care needs to be emphasized, providing visibility to professional practice and their contributions to achieving health quality. This study aimed to translate, validate, and culturally adapt the "Perception of Nursing Activities that Contribute to the Quality of Care" (EPAECQC), scale to provide a reliable instrument to assist nurse managers in measuring nurses' perceptions of their activities in French reality. Methods: A quantitative, descriptive, and cross-sectional study, in two phases, was conducted. First, by translation and cultural adaptation, and second, through the validation of the scale. Results: The factor structure of the final version was reduced to 22 items. Content and construct validity and reliability were supported by internal consistency (Cronbachs' alpha = .913). Conclusions: The results show that the final version is a reliable and valid instrument, showing a high potential to be used in research and clinical practice.info:eu-repo/semantics/publishedVersio