602 research outputs found
Pioners de l'animació: Chomón, Cohl, McCay / Els primers dibuixants del moviment
Emilio de la Rosa / Xavier Berengue
Efectes de la reperfusió després de la isquèmia cerebral: proteïnes d'estrès cel·lular, estrès oxidatiu i activació del complement
[cat] Globalment, aquesta tesi mostra diversos fenòmens que s’associen a la reperfusió després de la isquèmia cerebral. Per una banda, la inducció de la proteïna Hsp-70, a la que s’atribueixen propietats anti-apoptòtiques i protectores, promourà la supervivència neuronal en la zona de la penombra. La generació d’animals transgènics que expressen una proteïna fluorescent sota el promotor del gen Hsp-70 ens ha permès visualitzar en animals vius la zona de penombra mitjançant tècniques de microscòpia confocal intravital, així com monitoritzar aquesta expressió en regions cerebrals utilitzant tecnologia FRI. Malgrat la inducció de molècules protectores que facilitaran la supervivència neuronal a la zona de penombra, la reperfusió també comporta danys secundaris que s’associen principalment a estrès oxidatiu i inflamació. Aquests danys per reperfusió no s’observen en tots els animals sinó que es posen de manifest en aproximadament la meitat dels animals sotmesos a isquèmia transitòria seguida de reperfusió. Hem trobat que la hiperèmia reactiva en el moment de la reperfusió és un biomarcador de dany per reperfusió. El subgrup d’animals amb hiperèmia reactiva és el que és susceptible de respondre a tractaments antioxidants, com hem demostrat amb l’anàleg sintètic de la vitamina E, CR-6. L’administració oral de CR-6 dues hores després de l’inici de la isquèmia, protegeix els animals hiperèmics disminuint el volum d’infart cerebral i atenuant els dèficits neurològics. Aquesta protecció està relacionada amb una disminució de l’estrès oxidatiu a nivell de la vasculatura cerebral, menor alteració de la permeabilitat de la barrera hematoencefàlica, menor infiltració leucocitària i menor inflamació. La isquèmia/reperfusió també activa el complement. Hem demostrat que la via de les lectines està implicada en la lesió cerebral donat que els animals deficients en la proteïna MBL d’aquesta via tenen lesions de menor mida i presenten menys alteracions neurològiques. Hem demostrat que els efectes perjudicials de la MBL són deguts a la disminució del flux sanguini cerebral durant les hores que segueixen a la reperfusió post-isquèmia. Aquesta disminució està relacionada amb el dipòsit de fibrina/fibrinògen en la microvasculatura cerebral de la zona afectada i amb l’activació de la trombina, tal com demostren els efectes beneficiosos de l’inhibidor de trombina argatroban, que s’observen en els animals que tenen MBL però no en els animals deficients. Els resultats d’aquest treball permeten concloure que diferents estratègies per minimitzar el dany per reperfusió podrien incloure la inducció de l’expressió de Hsp-70 per afavorir la supervivència de les neurones de la penombra, i la inhibició tant de l’estrès oxidatiu com de l’activació del complement per la via de les lectines per evitar la trombosis secundària durant la reperfusió, atenuar l’estrès oxidatiu a l’endoteli vascular i prevenir la ruptura de la barrera hematoencefàlica i la inflamació tissular.[eng] Stroke induces strong expression of the 72-kDa heat-shock protein (HSP-70) in the ischaemic brain, and neuronal expression of HSP-70 is associated with the ischaemic penumbra. The aim of this study was to image induction of Hsp-70 gene expression in vivo after brain ischaemia using reporter mice. A genomic DNA sequence of the Hspa1b promoter was used to generate an Hsp70-mPlum far-red fluorescence reporter vector. The construct was tested in cellular systems (NIH3T3 mouse fibroblast cell line) by transient transfection and examining mPlum and Hsp-70 induction under a challenge. After construct validation, mPlum transgenic mice were generated. Focal brain ischaemia was induced by transient intraluminal occlusion of the middle cerebral artery and the mice were imaged in vivo with fluorescence reflectance imaging (FRI) with an intact skull, and with confocal microscopy after opening a cranial window. Cells transfected with the Hsp70-mPlum construct showed mPlum fluorescence after stimulation. One day after induction of ischaemia, reporter mice showed a FRI signal located in the HSP-70-positive zone within the ipsilateral hemisphere, as validated by immunohistochemistry. Live confocal microscopy allowed brain tissue to be visualized at the cellular level. mPlum fluorescence was observed in vivo in the ipsilateral cortex 1 day after induction of ischae- mia in neurons, where it is compatible with penumbra and neuronal viability, and in blood vessels in the core of the infarction. This study showed in vivo induction of Hsp-70 gene expression in ischaemic brain using reporter mice. The fluorescence signal showed in vivo the induction of Hsp-70 in penumbra neurons and in the vasculature within the ischaemic core. Several lines of evidence support the involvement of mannose-binding lectin (MBL) in stroke brain damage. The lectin pathway of the complement system facilitates thrombin activation and clot formation under certain experimental conditions. In the present study, we examine whether MBL promotes thrombosis after ischemia/reperfusion and influences the course and prognosis of ischemic stroke. Middle cerebral artery occlusion/reperfusion was performed in MBL-deficient and wild-type mice, and the brain lesion was assessed by MRI at days 1 and 7. Relative cerebral blood flow was monitored up to 6 hours after middle cerebral artery occlusion with laser speckle contrast imaging. Fibrin(ogen) was analyzed in the brain vasculature and plasma, and the effects of thrombin inhibitor argatroban were evaluated to assess the role of MBL in thrombin activation. Infarct volumes and neurological deficits were smaller in MBL knockout mice than in WT mice. Relative cerebral blood flow values during middle cerebral artery occlusion and at reperfusion were similar in both groups, but decreased during the next 6 hours in the WT group only. Also, the WT mice showed more fibrin(ogen) in brain vessels and a better outcome after argatroban treatment. In contrast, argatroban did not improve the outcome in MBL knockout mice. MBL promotes brain damage and functional impairment after brain ischemia/reperfusion in mice. These effects are secondary to intravascular thrombosis and impaired relative cerebral blood flow during reperfusion. Argatroban protects WT mice, but not MBL knockout mice, emphasizing a role of MBL in local thrombus formation in acute ischemia/reperfusion
Emotional Processing in Individuals with Borderline Personality Disorder and with Major Depressive Disorder
No campo da saúde mental, deficiências no processamento emocional têm sido evidenciadas em várias psicopatologias. Este estudo quantitativo, com delineamento quase-experimental, teve como objetivo geral investigar o Processamento Emocional (Reconhecimento de expressões faciais emocionais e a Desregulação Emocional) em amostra de indivíduos com Transtorno de Personalidade Borderline (TPB, n = 13) e com Transtorno Depressivo Maior (TDM, n = 20). Foi desenvolvida uma Tarefa de Reconhecimento de Faces especificamente para esta investigação. A tarefa consistiu na apresentação de 20 vídeos, de cinco segundos, com faces dinâmicas das emoções Alegria, Raiva, Medo, Tristeza e Faces Neutras. As hipóteses foram confirmadas parcialmente. Com relação ao reconhecimento de faces, no tempo de reação, o grupo TPB apresentou maior tempo de reação para as faces neutras com (p=0,014). Não foram encontradas diferenças estatisticamente significativas quanto à acurácia. Os resultados apontam, também, que os indivíduos com TPB apresentam maior Desregulação Emocional, medida por autorrelato por meio da Escala de Dificuldades de Regulação Emocional (DERS), do que o grupo TDM. A Desregulação Emocional nas subescalas da DERS apresentou diferença significativa entre grupos, apontando para maior Desregulação Emocional do TPB nas subescalas: Impulsos (p=0,001), Estratégias (p= 0,0009) e Clareza (p=0,0005).In the field of mental health, deficiencies in emotional processing have been evidenced in several psychopathologies. This quantitative study with a quasi-experimental design, aimed to investigate the Emotional Processing (Recognition of emotional facial expressions and Emotional Deregulation) in a sample of individuals with Borderline Personality Disorder (BPD, n = 13) and with Major Depressive Disorder (MDD, n = 20). A Face Recognition Task was developed specifically for this investigation. The task consisted of the presentation of 20 videos, of 5 seconds, with dynamic faces of the emotions Joy, Anger, Fear, Sadness and Neutral Faces. The hypotheses were partially confirmed. Regarding face recognition, in the reaction time, the TPB group showed a longer reaction time for neutral faces with (p=0,014). No statistically significant differences were found regarding accuracy. The results also point out that individuals with BPD have greater Emotional Deregulation, measured by self-report using the Emotional Regulation Difficulty Scale (DERS), than the MDD group. Emotional deregulation in the DERS subscales showed a significant difference between groups pointing to greater Emotional Deregulation of the BPD, in the subscales: Impulses (p = 0.001), Strategies (p = 0.0009) and Clarity (p =0.0005)
Influence of Saharan dust in deposition fluxes of nutrients in Spain
Comunicación presentada en: 2012 European Aerosol Conference (EAC-2012), B-WG01S2P30, celebrada del 2 al 7 de septiembre de 2012 en Granada
Ultrafine particle formation in the inland sea breeze airflow in Southwest Europe
Studies on ultrafine particles (diameter < 100nm) and air quality have mostly focused on vehicle exhaust emissions and on new particle formation in "clean" ambient air. Here we present a study focused on the processes contributing to ultrafine particle concentrations in a city (Huelva, SW Spain) placed close to a coastal area where significant anthropogenic emissions of aerosol precursors occur. The overall data analysis shows that two processes predominantly contribute to the number of particles coarser than 2.5 nm: vehicle exhaust emissions and new particle formation due to photo-chemical activity. As typically occurs in urban areas, vehicle exhaust emissions result in high concentrations of black carbon (BC) and particles coarser than 2.5 nm (N) during the morning rush hours. The highest N concentrations were recorded during the 11:00–17:00 h period, under the sea breeze regime, when low BC concentrations were registered and photochemical activity resulted in high O3 levels and in new particle formation in the aerosol precursors' rich inland airflow. In this period, it is estimated that about 80% of the number of particles are linked to sulfur dioxide emissions. The contributions to N of "carbonaceous material and those compounds nucleating/condensing immediately after emission" and of the "new particle formation processes in air masses rich gaseous precursors (e.g. SO2)" were estimated by means of a relatively novel method based on simultaneous measurements of BC and N. A comparison with two recent studies suggests that the daily cycles of "new particle formation" during the inland sea breeze is blowing period seem to be a feature of ultrafine particles in coastal areas of South-west Europe.This study has been carried out within the framework of several research projects: AER-REG (P07-RNM- 03125; Department of Innovation, Science and Enterprise of the Andalusian Autonomous Government), GRACCIE (CSD2007- 00067; Ministry of Science and Innovation of Spain), SIMAND (P07- RNM-02729; Department of Innovation, Science and Enterprise of the Andalusian Autonomous Government) and EPAU (B026/2007/3-10.1; Ministry of Environment of Spain)
Intracellular pathways involved in cell survival are deregulated in mouse and human spinal muscular atrophy motoneurons
Spinal Muscular Atrophy (SMA) is a severe neuromuscular disorder caused by loss of the Survival Motor Neuron 1 gene (SMN1). Due to this depletion of the survival motor neuron (SMN) protein, the disease is characterized by the degeneration of spinal cord motoneurons (MNs), progressive muscular atrophy, and weakness. Nevertheless, the ultimate cellular and molecular mechanisms leading to cell loss in SMN-reduced MNs are only partially known. We have investigated the activation of apoptotic and neuronal survival pathways in several models of SMA cells. Even though the antiapoptotic proteins FAIM-L and XIAP were increased in SMA MNs, the apoptosis executioner cleaved-caspase-3 was also elevated in these cells, suggesting the activation of the apoptosis process. Analysis of the survival pathway PI3K/Akt showed that Akt phosphorylation was reduced in SMA MNs and pharmacological inhibition of PI3K diminished SMN and Gemin2 at transcriptional level in control MNs. In contrast, ERK phosphorylation was increased in cultured mouse and human SMA MNs. Our observations suggest that apoptosis is activated in SMA MNs and that Akt phosphorylation reduction may control cell degeneration, thereby regulating the transcription of Smn and other genes related to SMN function.This work was supported by grants from Instituto de Salud Carlos III, Fondo de Investigaciones
Sanitarias, Unión Europea, Fondo Europeo de Desarrollo Regional (FEDER) “Una manera de
hacer Europa” (PI17/00231 and PI20/00098) to RMS and AG; CERCA Program/Generalitat de
Catalunya; and Spanish Agency of Research (Agencia Estatal de Investigacion-PID2019-
107286RB-I00) and CIBERNED to JXC. AS holds a fellowship from Universitat de Lleida and
SdF holds a fellowship from “Ajuts de Promoció de la Recerca en Salut” (IRBLleida-Diputació
de Lleida). We thank Elaine Lilly, PhD, for English language revision of the paper
BRAFV600E Mutant Allele Frequency (MAF) Influences Melanoma Clinicopathologic Characteristics
Background: Cutaneous melanoma shows high variability regarding clinicopathological presentation, evolution and prognosis. Methods: Next generation sequencing was performed to analyze hotspot mutations in different areas of primary melanomas (MMp) and their paired metastases. Clinicopathological features were evaluated depending on the degree of variation of the BRAFV600E mutant allele frequency (MAF) in MMp. Results: In our cohort of 14 superficial spreading, 10 nodular melanomas and 52 metastases, 17/24 (71%) melanomas had a BRAFV600E mutation and 5/24 (21%) had a NRASQ61 mutation. We observed a high variation of BRAFV600E MAF (H-BRAFV600E) in 7/17 (41%) MMp. The H-BRAFV600E MMp were all located on the trunk, had lower Breslow and mitotic indexes and predominantly, a first nodal metastasis. Regions with spindled tumor cells (Spin) and high lymphocytic infiltrate (HInf) were more frequent in the H-BRAFV600E patients (4/7; 57%), whereas regions with epithelial tumor cells (Epit) and low lymphocytic infiltrate (LInf) were predominant (6/10; 60%) and exclusive in the low BRAFV600E MAF variation tumors (L-BRAFV600E). The H-BRAFV600E/Spin/HInf MMp patients had better prognostic features and nodal first metastasis. Conclusions: The H-BRAFV600E MMp were located on the trunk, had better prognostic characteristics, such as lower Breslow and mitotic indexes as well as high lymphocytic infiltrate.This work was supported by grants from ISCIII and FEDER (“una manera de hacerEuropa”) PI15/00711 to RMM and PI18/00573 to RMM & AM. CIBERONC (CB16/12/00231) to XMG.Postdoctoral AECC (POSTD004MACI - POSTD16) to AM. Predoctoral UdL to PS and predoctoralAECC fellowship to IR. The work was also supported by the Xarxa de Bancs de Tumors de Catalunyasponsored by “Pla Director d’Oncologia de Catalunya (XBTC)”and IRBLleida Biobank (B.0000682)and PLATAFORMA BIOBANCOS (PT17/0015/0027; PT20/00021
Geochemistry of atmospheric aerosols in Andalusia (Southern Spain)
Comunicación presentada en: V Reunión Española de Ciencia y Tecnología de Aerosoles – RECTA 2011 celebrada del 27 al 29 de junio de 2011 en CIEMAT, Madrid
Pharmacokinetics and Changes in Lipid Mediator Profiling after Consumption of Specialized Pro-Resolving Lipid-Mediator-Enriched Marine Oil in Healthy Subjects
Omega-3 polyunsaturated fatty acids (PUFAs) play a vital role in human health, well-being, and the management of inflammatory diseases. Insufficient intake of omega-3 is linked to disease development. Specialized pro-resolving mediators (SPMs) are derived from omega-3 PUFAs and expedite the resolution of inflammation. They fall into categories known as resolvins, maresins, protectins, and lipoxins. The actions of SPMs in the resolution of inflammation involve restricting neutrophil infiltration, facilitating the removal of apoptotic cells and cellular debris, promoting efferocytosis and phagocytosis, counteracting the production of pro-inflammatory molecules like chemokines and cytokines, and encouraging a pro-resolving macrophage phenotype. This is an experimental pilot study in which ten healthy subjects were enrolled and received a single dose of 6 g of an oral SPM-enriched marine oil emulsion. Peripheral blood was collected at baseline, 3, 6, 9, 12, and 24 h post-administration. Temporal increases in plasma and serum SPM levels were found by using LC-MS/MS lipid profiling. Additionally, we characterized the temporal increases in omega-3 levels and established fundamental pharmacokinetics in both aforementioned matrices. These findings provide substantial evidence of the time-dependent elevation of SPMs, reinforcing the notion that oral supplementation with SPM-enriched products represents a valuable source of essential bioactive SPMs
Treatment of patients with COPD and recurrent exacerbations: the role of infection and inflammation
Exacerbations of COPD represent an important medical and health care problem. Certain susceptible patients suffer recurrent exacerbations and as a consequence have a poorer prognosis. The effects of bronchial infection, either acute or chronic, and of the inflammation characteristic of the disease itself raise the question of the possible role of antibiotics and anti-inflammatory agents in modulating the course of the disease. However, clinical guidelines base their recommendations on clinical trials that usually exclude more severe patients and patients with more comorbidities, and thus often fail to reflect the reality of clinicians attending more severe patients. In order to discuss aspects of clinical practice of relevance to pulmonologists in the treatment and prevention of recurrent exacerbations in patients with severe COPD, a panel discussion was organized involving expert pulmonologists who devote most of their professional activity to day hospital care. This article summarizes the scientific evidence currently available and the debate generated in relation to the following aspects: bacterial and viral infections, chronic bronchial infection and its treatment with cyclic oral or inhaled antibiotics, inflammatory mechanisms and their treatment, and the role of computerized tomography as a diagnostic tool in patients with severe COPD and frequent exacerbations
- …