506 research outputs found

    Redox Reactions in the Physiopathology of the Liver

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    Electron fluxes are constant within cellular metabolism. Donating or accepting electrons, either naked or as hydrogen atoms, is one of the most important properties of bioenergetic networks. These redox reactions fulfill key physiological phenomena such as cellular growing, phenotypic differentiation, nutritional adaptations and redox‐dependent cellular signaling, but when they became unregulated, serious pathologies such as degenerative diseases and metabolic disorders arise. The liver being an important metabolic organ, redox reactions play a strategic role in its main functions: processing of nutrients, fasting response, xenobiotic managing and circadian activity. However, liver is also very sensitive to compounds that disturb redox state such as ethanol, CCl4, aflatoxins, among others, as well as to stressors such as hypercaloric diets, endocrine disruptors and stressful life situations. This chapter reviews concepts related to redox reactions in the liver, including metabolic aspects of reactive oxygen species (ROS), prooxidant and antioxidant subcellular systems, alterations produced by hepatotoxins, adaptations to experimental surgical protocols such as portacaval anastomosis, and participation in cancer. It is out of question that for a better comprehension of the physiopathological events in the liver and other metabolic organs, the more complete understanding of the roles played by redox reactions will be a necessity

    Functional expression and intracellular signaling of UTP-sensitive P2Y receptors in theca-interstitial cells

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    <p>Abstract</p> <p>Background</p> <p>Purinergic receptors are expressed in the ovary of different species; their physiological roles remain to be elucidated. UTP-sensitive P2Y receptor activity may regulate cell proliferation. The aim of the present work was to study the functional expression of these receptors in theca/interstitial cells (TIC).</p> <p>Methods</p> <p>TIC were isolated by centrifugation in a Percoll gradient. P2Y receptors and cellular markers in TIC were detected by RT-PCR and Western blot. Intracellular calcium mobilization induced by purinergic drugs was evaluated by fluorescence microscopy, phosphorylation of MAPK p44/p42 and of cAMP response element binding protein (CREB) was determined by Western blot and proliferation was quantified by [3H]-thymidine incorporation into DNA.</p> <p>Results</p> <p>RT-PCR showed expression of p2y2r and p2y6r transcripts, expression of the corresponding proteins was confirmed. UTP and UDP, agonists for P2Y2 and P2Y6 receptors, induced an intracellular calcium increase with a maximum of more than 400% and 200% of basal level, respectively. The response elicited by UTP had an EC50 of 3.5 +/- 1.01 ÎŒM, while that for UDP was 3.24 +/- 0.82 ÎŒM. To explore components of the pathway activated by these receptors, we evaluated the phosphorylation induced by UTP or UDP of MAPK p44 and p42. It was found that UTP increased MAPK phosphorylation by up to 550% with an EC50 of 3.34 +/- 0.92 and 1.41 +/- 0.67 ÎŒM, for p44 and p42, respectively; these increases were blocked by suramin. UDP also induced p44/p42 phosphorylation, but at high concentrations. Phosphorylation of p44/p42 was dependent on PKC and intracellular calcium. To explore possible roles of this pathway in cell physiology, cell proliferation and hCG-induced CREB-phosphorylation assays were performed; results showed that agonists increased cell proliferation and prevented CREB-phosphorylation.</p> <p>Conclusion</p> <p>Here, it is shown that UTP-sensitive P2Y receptors are expressed in cultured TIC and that these receptors had the ability to activate mitogenic signaling pathways and to promote cell proliferation, as well as to prevent CREB-phosphorylation by hCG. Regulation of TIC proliferation and steroidogenesis is relevant in ovarian pathophysiology since theca hyperplasia is involved in polycystic ovarian syndrome. Purinergic receptors described might represent an important new set of molecular therapeutic targets.</p

    Purinergic Signaling: A New Regulator of Ovarian Function

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    Purinergic signaling is a sophisticated system of elements in which ATP and related molecules function as intercellular messengers. When ATP is released into the extracellular space, it activates specific receptors that belong to the P2 family. In parallel, ectonucleotidases transform ATP in its dephosphorylated metabolites including adenosine, which stimulates P1 receptors. The activity of both receptors influences various cellular processes. Moreover, metabolic conditions are concatenated with purine signaling to conform a dynamic and continuous informational network. The role of purinergic signaling in ovarian cells has been investigated, for instance, it is known that cells conforming the follicle express functional receptors that modulate basic cellular process such as proliferation, induction of apoptotic cell death, and steroidogenesis. In this chapter, we review contemporary information on purinergic action in ovarian cell physiology and state its relevance in this field

    Taxonomic variations in the gut microbiome of gout patients with and without tophi might have a functional impact on urate metabolism

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    [Objective] To evaluate the taxonomic composition of the gut microbiome in gout patients with and without tophi formation, and predict bacterial functions that might have an impact on urate metabolism.[Methods] Hypervariable V3–V4 regions of the bacterial 16S rRNA gene from fecal samples of gout patients with and without tophi (n = 33 and n = 25, respectively) were sequenced and compared to fecal samples from 53 healthy controls. We explored predictive functional profiles using bioinformatics in order to identify differences in taxonomy and metabolic pathways. [Results] We identified a microbiome characterized by the lowest richness and a higher abundance of Phascolarctobacterium, Bacteroides, Akkermansia, and Ruminococcus_gnavus_group genera in patients with gout without tophi when compared to controls. The Proteobacteria phylum and the Escherichia-Shigella genus were more abundant in patients with tophaceous gout than in controls. Fold change analysis detected nine genera enriched in healthy controls compared to gout groups (Bifidobacterium, Butyricicoccus, Oscillobacter, Ruminococcaceae_UCG_010, Lachnospiraceae_ND2007_group, Haemophilus, Ruminococcus_1, Clostridium_sensu_stricto_1, and Ruminococcaceae_UGC_013). We found that the core microbiota of both gout groups shared Bacteroides caccae, Bacteroides stercoris ATCC 43183, and Bacteroides coprocola DSM 17136. These bacteria might perform functions linked to one-carbon metabolism, nucleotide binding, amino acid biosynthesis, and purine biosynthesis. Finally, we observed differences in key bacterial enzymes involved in urate synthesis, degradation, and elimination. [Conclusion] Our findings revealed that taxonomic variations in the gut microbiome of gout patients with and without tophi might have a functional impact on urate metabolism.This study was supported by the Instituto Nacional de Rehabilitación Luis Guillermo Ibarra Ibarra” and the Grant INF-2016-01-269675 from the Consejo Nacional de Ciencia y Tecnología (CONACYT)

    Vertidos tóxicos al río Guadiamar: propuestas técnicas para su corrección

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    Inmediatamente de producirse el vertido tĂłxico al rĂ­o Guadiamar, el Grupo T.A.R. se lanzĂł sin pensarlo dos veces a la bĂșsqueda de soluciones tĂ©cnicas a un panorama desolador y de efectos desconocidos, todos ellos amenazantes. El ĂĄcido “se comĂ­a el suelo inundado” por la riada, el agua retenida en Entremuros a pH 3, y con un enorme contenido de metales pesados, ocupaba una extensiĂłn de kilĂłmetros. Nos hundimos en el agua hasta el cuello, y cuando nos cubrĂ­a cogimos la barca, metimos el rĂ­o a pedazos en nuestro laboratorio, para trabajar todas las hipĂłtesis, ensayar todas las posibilidades. Peleando con la realidad le sacamos datos al Guadiamar, diseñamos actuaciones, poniĂ©ndole ingenierĂ­a a cuantas hipĂłtesis nos planteaba la situaciĂłn. En primera fila observamos las mejores actuaciones que nadie diseñó. El propio rĂ­o, activando sus defensas naturales, mejorĂł la calidad del agua retenida en el dique de Entremuros subiendo el pH y precipitando los metales pesados. Los mecanismos de entrada de los metales pesados en la cadena trĂłfica parecĂ­an ser lentos, dando tiempo a que la retirada de los lodos tĂłxicos llevada a cabo por la AdministraciĂłn fuera eficaz y diera tiempo a realizar tanto esfuerzo. Aunque el Guadiamar ha trabajado muy duro en su propia recuperaciĂłn, con su ayuda hemos elaborado una gran cantidad de propuestas tĂ©cnicas; unas para actuaciones de emergencia, otras a corto, medio y largo plazo. TambiĂ©n hemos dado forma a un Plan frente a las previsibles avenidas de este primer otoño despuĂ©s del vertido. Nuestro objetivo ha sido poner a disposiciĂłn soluciones preparadas para todo tipo de problemas, en primera o en segunda instancia. Prevenir no solo una o dos contingencias, se ha tratado de estar preparado para la mayor cantidad de eventualidades posibles. Por ello algunas serĂĄn utilizables, otras estarĂĄn en reserva, y muchas irĂ­an al cajĂłn de los papeles. Pero ahĂ­ estĂĄn por si acaso. Este libro recoge los trabajos de campo, los ensayos de laboratorio y la ingenierĂ­a desarrollada en los primeros cuatro meses. Durante el siguiente preparamos la ediciĂłn del mismo, mientras, en paralelo, continuĂĄbamos en el trabajo experimental y el diseño. Cuando se cumpla el quinto mes, el 25 de Septiembre de 1998, lo presentaremos, ciento cincuenta dĂ­as despuĂ©s... Con la financiaciĂłn de la DiputaciĂłn de Sevilla hemos preparado la primera ediciĂłn en formato CD Rom e Internet, con muy poco coste para acceder a su contenido. En poco tiempo saldrĂĄ la ediciĂłn en papel, con la misma financiaciĂłn que la primera. Nos gustarĂ­a que este documento fuera entendido como lo que es, en nuestra opiniĂłn, una llamada urgente al debate de las ideas. Tratamos de ofrecer la informaciĂłn necesaria y el foro donde recoger las propuestas que seguramente muchos pueden aportar sin saber como transmitir sus experiencias. El Grupo de Tratamiento de Aguas Residuales (T.A.R.) abre con este libro la MESA DE DISCUSIÓN, para buscar un poco de luz, avanzar en las soluciones tĂ©cnicas a la inmensa tarea de recuperar el rĂ­o Guadiamar. El libro presenta lagunas, unas por la enorme prisa, otra por falta de datos, muchas por nuestra escasez de conocimientos. Dicen en España que “lo mejor es enemigo de lo bueno”...,y nos gustarĂ­a recoger ideas hoy mejor que mañana, que podrĂ­a ser tarde. Nos comprometemos a seguir trabajando en soluciones tĂ©cnicas, innovaciones tecnolĂłgicas e investigaciĂłn aplicada a la recuperaciĂłn del Guadiamar, a conocer lo ocurrido y su remedio. Nos comprometemos a publicar de la misma forma los resultados obtenidos, de manera que la discusiĂłn y el debate sigan siempre abiertos. El grupo T.A.R. podrĂ­a ser un punto de intercambio de conocimientos universal, abierto, respetuoso y tolerante, universitario en definitiva, y por tanto Ăștil en el cumplimiento de sus obligaciones. La primera necesidad de responder urgentemente, estĂĄ dando paso a unas actuaciones programadas, a medida de los efectos de las correcciones introducidas. Deben instaurarse polĂ­ticas de prevenciĂłn y nuevas actuaciones para recuperar el Guadiamar, mejorar urgentemente las condiciones del entorno. Aprender de las soluciones adoptadas y generar mejores prĂĄcticas, puede ser una buena conclusiĂłn del trabajo realizado por tanta gente. Lo que empezĂł siendo una carrera de velocidad se nos convierte en un maratĂłn, ya no hay que correr explosivamente, hay que mantener un ritmo en la carrera; hay que persistir en el esfuerzo todos los dĂ­as durante mucho tiempo. Este nuevo desafĂ­o sigue siendo duro y difĂ­cil. PodĂ©is contar con el Grupo T.A.R. para recorrer el duro camino de la RecuperaciĂłn

    Non-motor symptom burden in patients with Parkinson's disease with impulse control disorders and compulsive behaviours : results from the COPPADIS cohort

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    The study was aimed at analysing the frequency of impulse control disorders (ICDs) and compulsive behaviours (CBs) in patients with Parkinson's disease (PD) and in control subjects (CS) as well as the relationship between ICDs/CBs and motor, nonmotor features and dopaminergic treatment in PD patients. Data came from COPPADIS-2015, an observational, descriptive, nationwide (Spain) study. We used the validated Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease-Rating Scale (QUIP-RS) for ICD/CB screening. The association between demographic data and ICDs/CBs was analyzed in both groups. In PD, this relationship was evaluated using clinical features and treatment-related data. As result, 613 PD patients (mean age 62.47 ± 9.09 years, 59.87% men) and 179 CS (mean age 60.84 ± 8.33 years, 47.48% men) were included. ICDs and CBs were more frequent in PD (ICDs 12.7% vs. 1.6%, p < 0.001; CBs 7.18% vs. 1.67%, p = 0.01). PD patients had more frequent previous ICDs history, premorbid impulsive personality and antidepressant treatment (p < 0.05) compared with CS. In PD, patients with ICDs/CBs presented younger age at disease onset, more frequent history of previous ICDs and premorbid personality (p < 0.05), as well as higher comorbidity with nonmotor symptoms, including depression and poor quality of life. Treatment with dopamine agonists increased the risk of ICDs/CBs, being dose dependent (p < 0.05). As conclusions, ICDs and CBs were more frequent in patients with PD than in CS. More nonmotor symptoms were present in patients with PD who had ICDs/CBs compared with those without. Dopamine agonists have a prominent effect on ICDs/CBs, which could be influenced by dose

    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

    Familial hypercholesterolaemia in children and adolescents from 48 countries: a cross-sectional study

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    Background: Approximately 450 000 children are born with familial hypercholesterolaemia worldwide every year, yet only 2·1% of adults with familial hypercholesterolaemia were diagnosed before age 18 years via current diagnostic approaches, which are derived from observations in adults. We aimed to characterise children and adolescents with heterozygous familial hypercholesterolaemia (HeFH) and understand current approaches to the identification and management of familial hypercholesterolaemia to inform future public health strategies. Methods: For this cross-sectional study, we assessed children and adolescents younger than 18 years with a clinical or genetic diagnosis of HeFH at the time of entry into the Familial Hypercholesterolaemia Studies Collaboration (FHSC) registry between Oct 1, 2015, and Jan 31, 2021. Data in the registry were collected from 55 regional or national registries in 48 countries. Diagnoses relying on self-reported history of familial hypercholesterolaemia and suspected secondary hypercholesterolaemia were excluded from the registry; people with untreated LDL cholesterol (LDL-C) of at least 13·0 mmol/L were excluded from this study. Data were assessed overall and by WHO region, World Bank country income status, age, diagnostic criteria, and index-case status. The main outcome of this study was to assess current identification and management of children and adolescents with familial hypercholesterolaemia. Findings: Of 63 093 individuals in the FHSC registry, 11 848 (18·8%) were children or adolescents younger than 18 years with HeFH and were included in this study; 5756 (50·2%) of 11 476 included individuals were female and 5720 (49·8%) were male. Sex data were missing for 372 (3·1%) of 11 848 individuals. Median age at registry entry was 9·6 years (IQR 5·8-13·2). 10 099 (89·9%) of 11 235 included individuals had a final genetically confirmed diagnosis of familial hypercholesterolaemia and 1136 (10·1%) had a clinical diagnosis. Genetically confirmed diagnosis data or clinical diagnosis data were missing for 613 (5·2%) of 11 848 individuals. Genetic diagnosis was more common in children and adolescents from high-income countries (9427 [92·4%] of 10 202) than in children and adolescents from non-high-income countries (199 [48·0%] of 415). 3414 (31·6%) of 10 804 children or adolescents were index cases. Familial-hypercholesterolaemia-related physical signs, cardiovascular risk factors, and cardiovascular disease were uncommon, but were more common in non-high-income countries. 7557 (72·4%) of 10 428 included children or adolescents were not taking lipid-lowering medication (LLM) and had a median LDL-C of 5·00 mmol/L (IQR 4·05-6·08). Compared with genetic diagnosis, the use of unadapted clinical criteria intended for use in adults and reliant on more extreme phenotypes could result in 50-75% of children and adolescents with familial hypercholesterolaemia not being identified. Interpretation: Clinical characteristics observed in adults with familial hypercholesterolaemia are uncommon in children and adolescents with familial hypercholesterolaemia, hence detection in this age group relies on measurement of LDL-C and genetic confirmation. Where genetic testing is unavailable, increased availability and use of LDL-C measurements in the first few years of life could help reduce the current gap between prevalence and detection, enabling increased use of combination LLM to reach recommended LDL-C targets early in life

    Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

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    Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio
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