32 research outputs found

    Alteraciones neurológicas (cognitivas y motoras) en ratas expuestas perinatalmente a pesticidas contaminantes ambientales. Mecanismos moleculares implicados

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    El uso de substancias químicas en agricultura y en el hogar para combatir una gran variedad de plagas ha sido generalizado durante todo el siglo pasado, ya que de lo contrario estas plagas menguarían la producción de las cosechas como fuente de alimento. Sin embargo estos beneficios vienen asociados con una serie de perjuicios ya no sólo a nivel de ecosistemas (pérdida de diversidad) sino que conllevan consecuencias para la salud humana. Debido a que la mayoría de los pesticidas actúan sobre el sistema nervioso de los insectos y los procesos neuroquímicos son similares a los del sistema nervioso de humanos, los hace especialmente peligrosos por su neurotoxicidad. En los últimos años se ha observado un aumento de la incidencia de trastornos del aprendizaje y del desarrollo en niños. Durante el desarrollo el cerebro es mucho más vulnerable a la neurotoxicidad de compuestos químicos que el cerebro de los adultos. La exposición a pesticidas durante el desarrollo se ha asociado con alteraciones neurológicas en niños. Existen evidencias de que algunas alteraciones cognitivas y motoras pueden persistir en adultos y aumentar el riesgo de padecer algunas enfermedades como el Parkinson. Sin embargo no se conocen bien los mecanismos por los que la exposición a diferentes pesticidas durante el desarrollo lleva a diferentes alteraciones cognitivas, motoras o de conducta. Las formulaciones de los pesticidas no están compuestas por un solo pesticida sino que son casi siempre mezclas de varios compuestos. Además, en el medio ambiente la falta de desintegración de algunos de ellos hace que los seres vivos estén expuestos a una mezcla de compuestos. El objetivo general de la tesis ha sido analizar las alteraciones neurológicas en ratas adultas expuestas durante el desarrollo a diferentes pesticidas, individuales y en mezcla, analizar los mecanismos implicados y las diferencias según el sexo. La exposición a endosulfán empeora el aprendizaje y memoria espaciales asociado con un aumento de interleucina 1beta en hipocampo, empeora el aprendizaje asociativo e induce ansiedad en machos, mientras que en hembras deteriora la coordinación motora, asociado con un aumento de GABA en el cerebelo. El cipermetrín empeora un tipo de aprendizaje espacial (la memoria de referencia en el radial) pero también mejora otro (memoria de referencia en el Morris) y disminuye la actividad motora en machos. Al igual que el endosulfán, el cipermetrín deteriora la coordinación motora y aumenta el GABA en cerebelo en hembras. El clorpirifos empeora el aprendizaje espacial, aumenta la interleucina 1beta en hipocampo y aumenta la actividad motora y el contenido de la subunidad NR2B del receptor NMDA en hipocampo. El carbaril produce menos alteraciones, a pesar de utilizarse una dosis mayor. La mezcla de cipermetrín y endosulfán empeora la memoria espacial en machos por un efecto sinérgico aunque también previene alteraciones inducidas por la exposición individual, como la coordinación motora y el aumento de GABA en cerebelo en hembras. Finalmente se ha observado que las hembras control realizan peor las tareas de aprendizaje espacial pero mejor las de aprendizaje asociativo y tienen mayor actividad motora que los machos

    Jóvenes: sujetos de la contemporaneidad

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    Uno de los campos que tuvo un gran desarrollo en los estudios del campo de la comunicación son los llamados investigadores de juventud como Rossana Reguillo en México y Mario Margulis en Argentina, quienes estudian la emergencia de culturas juveniles en el mundo contemporáneo. Los autores coinciden en que, de maneras diversas, con mayor o menor grado de formulación, una de las características de los grupos juveniles es que han aprendido a tomar la palabra a su manera y a reapropiarse de los instrumentos de comunicación. Así, por ejemplo, los graffitis, los ritmos urbanos, los consumos culturales, la relación con el cuerpo, la búsqueda de alternativas y los compromisos itinerantes son analizados como formas de actuación política no institucionalizada que escapan a las formas tradicionales de concebir el ejercicio político por parte de los jóvenes.Facultad de Periodismo y Comunicación Socia

    Bicuculline Reduces Neuroinflammation in Hippocampus and Improves Spatial Learning and Anxiety in Hyperammonemic Rats. Role of Glutamate Receptors

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    Patients with liver cirrhosis may develop minimal hepatic encephalopathy (MHE) with mild cognitive impairment. Hyperammonemia is a main contributor to cognitive impairment in MHE, which is mediated by neuroinflammation. GABAergic neurotransmission is altered in hyperammonemic rats. We hypothesized that, in hyperammonemic rats, (a) enhanced GABAergic tone would contribute to induce neuroinflammation, which would be improved by reducing GABAergic tone by chronic bicuculline treatment; (b) this would improve spatial learning and memory impairment; and (c) modulation of glutamatergic neurotransmission would mediate this cognitive improvement. The aim of this work was to assess the above hypotheses. Bicuculline was administrated intraperitoneally once a day for 4 weeks to control and hyperammonemic rats. The effects of bicuculline on microglia and astrocyte activation, IL-1β content, on membrane expression of AMPA and NMDA glutamate receptors subunits in the hippocampus and on spatial learning and memory as well as anxiety were assessed. Treatment with bicuculline reduces astrocyte activation and IL-1β but not microglia activation in the hippocampus of hyperammonemic rats. Bicuculline reverses the changes in membrane expression of AMPA receptor subunits GluA1 and GluA2 and of the NR2B (but not NR1 and NR2A) subunit of NMDA receptors. Bicuculline improves spatial learning and working memory and decreases anxiety in hyperammonemic rats. In hyperammonemia, enhanced activation of GABAA receptors in the hippocampus contributes to some but not all aspects of neuroinflammation, to altered glutamatergic neurotransmission and to impairment of spatial learning and memory as well as anxiety, all of which are reversed by reducing activation of GABAA receptors with bicuculline

    Preservation of anti-SARS-CoV-2 neutralising antibodies in convalescent plasma after pathogen reduction with methylene blue and visible light

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    Background - COVID-19 convalescent plasma (CCP) is an experimental treatment against SARS-CoV-2. Although there has so far been no evidence of transmission through transfusion, pathogen reduction technologies (PRT) have been applied to CCP to mitigate risk of infectious disease. This study aims to assess the impact of methylene blue (MB) plus visible light PRT on the virus-neutralising activity of the specific antibodies against SARS-CoV-2. Material and methods - Thirty-five plasma doses collected by plasmapheresis from COVID-19 convalescent donors were subjected to MB plus visible light PRT. Anti-SARS-CoV-2 RBD S1 epitope IgGs antibodies were quantified by ELISA. Titres of SARS-CoV-2 neutralising antibodies (NtAbs) were measured before and after the PRT process. A Spearman's correlation was run to determine the relationship between antibody neutralisation ability and SARS-CoV-2 IgG ELISA ratio. Pre- and post-inactivation neutralising antibody titres were evaluated using a Wilcoxon test. Results - The plasma pathogen reduction procedure did not diminish NtAbS titres and so did not cause a change in the viral neutralisation capacity of CCP. There was a strong correlation between pre-and post-PRT NtAbs and anti-SARS-CoV-2 IgGs titres. Discussion - Our results showed PRT with MB did not impair the CCP passive immunity preserving its potential therapeutic potency. Therefore, PRT of CCP should be recommended to mitigate the risk for transmission of transfusionassociated infectious disease. There is a good correlation between SARS-CoV-2 IgG titres determined by ELISA and the neutralising capacity. This allows blood centres to select CCP donors based on IgG ELISA titres avoiding the much more labour-intensive laboratory processes for determining neutralising antibodies.Peer reviewe

    Differential Expression of PGC-1α and Metabolic Sensors Suggest Age-Dependent Induction of Mitochondrial Biogenesis in Friedreich Ataxia Fibroblasts

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    11 pages, 6 figures. PMID:21687738[PubMed] PMCID: PMC3110204BACKGROUND: Friedreich's ataxia (FRDA) is a mitochondrial rare disease, which molecular origin is associated with defect in the expression of frataxin. The pathological consequences are degeneration of nervous system structures and cardiomyopathy with necrosis and fibrosis, among others. PRINCIPAL FINDINGS: Using FRDA fibroblasts we have characterized the oxidative stress status and mitochondrial biogenesis. We observed deficiency of MnSOD, increased ROS levels and low levels of ATP. Expression of PGC-1α and mtTFA was increased and the active form of the upstream signals p38 MAPK and AMPK in fibroblasts from two patients. Interestingly, the expression of energetic factors correlated with the natural history of disease of the patients, the age when skin biopsy was performed and the size of the GAA expanded alleles. Furthermore, idebenone inhibit mitochondriogenic responses in FRDA cells. CONCLUSIONS: The induction of mitochondrial biogenesis in FRDA may be a consequence of the mitochondrial impairment associated with disease evolution. The increase of ROS and the involvement of the oxidative phosphorylation may be an early event in the cell pathophysiology of frataxin deficiency, whereas increase of mitochondriogenic response might be a later phenomenon associated to the individual age and natural history of the disease, being more evident as the patient age increases and disease evolves. This is a possible explanation of heart disease in FRDA.This work was supported by grants SAF2008-01338, SAF2006-01047 and SAF2009-07063 from the Ministerio de Ciencia e Innovación and financial support from the CIBERER (Biomedical Network Research Center for Rare Diseases). A.G. thanks the Conselleria de Educación of the Generalitat Valenciana for the financial support by grants GVPRE/2008/154. A.B.-A. is the recipient of a JAE-CSIC predoctoral fellowship. The CIBERER is an initiative of the Instituto de Salud Carlos III and INGENIO 2010.Peer reviewe

    COVID-19 outbreaks in a transmission control scenario: challenges posed by social and leisure activities, and for workers in vulnerable conditions, Spain, early summer 2020

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    Severe acute respiratory syndrome coronavirus 2 community-wide transmission declined in Spain by early May 2020, being replaced by outbreaks and sporadic cases. From mid-June to 2 August, excluding single household outbreaks, 673 outbreaks were notified nationally, 551 active (>6,200 cases) at the time. More than half of these outbreaks and cases coincided with: (i) social (family/friends’ gatherings or leisure venues) and (ii) occupational (mainly involving workers in vulnerable conditions) settings. Control measures were accordingly applied

    Treatment with tocilizumab or corticosteroids for COVID-19 patients with hyperinflammatory state: a multicentre cohort study (SAM-COVID-19)

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    Objectives: The objective of this study was to estimate the association between tocilizumab or corticosteroids and the risk of intubation or death in patients with coronavirus disease 19 (COVID-19) with a hyperinflammatory state according to clinical and laboratory parameters. Methods: A cohort study was performed in 60 Spanish hospitals including 778 patients with COVID-19 and clinical and laboratory data indicative of a hyperinflammatory state. Treatment was mainly with tocilizumab, an intermediate-high dose of corticosteroids (IHDC), a pulse dose of corticosteroids (PDC), combination therapy, or no treatment. Primary outcome was intubation or death; follow-up was 21 days. Propensity score-adjusted estimations using Cox regression (logistic regression if needed) were calculated. Propensity scores were used as confounders, matching variables and for the inverse probability of treatment weights (IPTWs). Results: In all, 88, 117, 78 and 151 patients treated with tocilizumab, IHDC, PDC, and combination therapy, respectively, were compared with 344 untreated patients. The primary endpoint occurred in 10 (11.4%), 27 (23.1%), 12 (15.4%), 40 (25.6%) and 69 (21.1%), respectively. The IPTW-based hazard ratios (odds ratio for combination therapy) for the primary endpoint were 0.32 (95%CI 0.22-0.47; p < 0.001) for tocilizumab, 0.82 (0.71-1.30; p 0.82) for IHDC, 0.61 (0.43-0.86; p 0.006) for PDC, and 1.17 (0.86-1.58; p 0.30) for combination therapy. Other applications of the propensity score provided similar results, but were not significant for PDC. Tocilizumab was also associated with lower hazard of death alone in IPTW analysis (0.07; 0.02-0.17; p < 0.001). Conclusions: Tocilizumab might be useful in COVID-19 patients with a hyperinflammatory state and should be prioritized for randomized trials in this situatio

    Association Between Preexisting Versus Newly Identified Atrial Fibrillation and Outcomes of Patients With Acute Pulmonary Embolism

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    Background Atrial fibrillation (AF) may exist before or occur early in the course of pulmonary embolism (PE). We determined the PE outcomes based on the presence and timing of AF. Methods and Results Using the data from a multicenter PE registry, we identified 3 groups: (1) those with preexisting AF, (2) patients with new AF within 2 days from acute PE (incident AF), and (3) patients without AF. We assessed the 90-day and 1-year risk of mortality and stroke in patients with AF, compared with those without AF (reference group). Among 16 497 patients with PE, 792 had preexisting AF. These patients had increased odds of 90-day all-cause (odds ratio [OR], 2.81; 95% CI, 2.33-3.38) and PE-related mortality (OR, 2.38; 95% CI, 1.37-4.14) and increased 1-year hazard for ischemic stroke (hazard ratio, 5.48; 95% CI, 3.10-9.69) compared with those without AF. After multivariable adjustment, preexisting AF was associated with significantly increased odds of all-cause mortality (OR, 1.91; 95% CI, 1.57-2.32) but not PE-related mortality (OR, 1.50; 95% CI, 0.85-2.66). Among 16 497 patients with PE, 445 developed new incident AF within 2 days of acute PE. Incident AF was associated with increased odds of 90-day all-cause (OR, 2.28; 95% CI, 1.75-2.97) and PE-related (OR, 3.64; 95% CI, 2.01-6.59) mortality but not stroke. Findings were similar in multivariable analyses. Conclusions In patients with acute symptomatic PE, both preexisting AF and incident AF predict adverse clinical outcomes. The type of adverse outcomes may differ depending on the timing of AF onset.info:eu-repo/semantics/publishedVersio

    Aprendizajes y prácticas educativas en las actuales condiciones de época: COVID-19

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    “Esta obra colectiva es el resultado de una convocatoria a docentes, investigadores y profesionales del campo pedagógico a visibilizar procesos investigativos y prácticas educativas situadas en el marco de COVI-19. La misma se inscribe en el trabajo llevado a cabo por el equipo de Investigación responsable del Proyecto “Sentidos y significados acerca de aprender en las actuales condiciones de época: un estudio con docentes y estudiantes de la educación secundarias en la ciudad de Córdoba” de la Facultad de Filosofía y Humanidades. Universidad Nacional de Córdoba. El momento excepcional que estamos atravesando, pero que también nos atraviesa, ha modificado la percepción temporal a punto tal que habitamos un tiempo acelerado y angustiante que nos exige la producción de conocimiento provisorio. La presente publicación surge como un espacio para detenernos a documentar lo que nos acontece y, a su vez, como oportunidad para atesorar y resguardar las experiencias educativas que hemos construido, inventado y reinventando en este contexto. En ella encontrarán pluralidad de voces acerca de enseñar y aprender durante la pandemia. Este texto es una pausa para reflexionar sobre el hacer y las prácticas educativas por venir”.Fil: Beltramino, Lucia (comp.). Universidad Nacional de Córdoba. Facultad de Filosofía y Humanidades. Escuela de Archivología; Argentina
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