12 resultados para beta-blocker therapy
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Autism and Alzheimer's disease (AD) are, respectively, neurodevelopmental and degenerative diseases with an increasing epidemiological burden. The AD-associated amyloid-beta precursor protein-alpha has been shown to be elevated in severe autism, leading to the 'anabolic hypothesis' of its etiology. Here we performed a focused microarray analysis of genes belonging to NOTCH and WNT signaling cascades, as well as genes related to AD and apoptosis pathways in cerebellar samples from autistic individuals, to provide further evidence for pathological relevance of these cascades for autism. By using the limma package from R and false discovery rate, we demonstrated that 31% (116 out of 374) of the genes belonging to these pathways displayed significant changes in expression (corrected P-values <0.05), with mitochondria- related genes being the most downregulated. We also found upregulation of GRIN1, the channel-forming subunit of NMDA glutamate receptors, and MAP3K1, known activator of the JNK and ERK pathways with anti-apoptotic effect. Expression of PSEN2 (presinilin 2) and APBB1 (or F65) were significantly lower when compared with control samples. Based on these results, we propose a model of NMDA glutamate receptor-mediated ERK activation of alpha-secretase activity and mitochondrial adaptation to apoptosis that may explain the early brain overgrowth and disruption of synaptic plasticity and connectome in autism. Finally, systems pharmacology analyses of the model that integrates all these genes together (NOWADA) highlighted magnesium (Mg2+) and rapamycin as most efficient drugs to target this network model in silico. Their potential therapeutic application, in the context of autism, is therefore discussed.
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Cardiovascular diseases are nowadays the first cause of mortality worldwide, causing around the 30% of global deaths each year. The risk of suffering from cardiovascular illnesses is strongly related to some factors such as hypertension, high cholesterol levels, diabetes, obesity The combination of these different risk factors is known as metabolic syndrome and it is considered a pandemic due to the high prevalence worldwide. The pathology of the disorders implies a combined cardiovascular therapy with drugs which have different targets and mechanisms of action, to regulate each factor separately. The simultaneous analysis of these drugs turns interesting but it is a complex task since the determination of multiple substances with different physicochemical properties and physiological behavior is always a challenge for the analytical chemist. The complexity of the biological matrices and the difference in the expected concentrations of some analytes require the development of extremely sensitive and selective determination methods. The aim of this work is to fill the gap existing in this field of the drug analysis, developing analytical methods capable of quantifying the different drugs prescribed in combined cardiovascular therapy simultaneously. Liquid chromatography andem mass spectrometry (LCMS/MS) has been the technique of choice throughout the main part of this work, due to the high sensitivity and selectivity requirements.
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1-42 beta-Amyloid (A beta(1-42)) peptide is a key molecule involved in the development of Alzheimer's disease. Some of its effects are manifested at the neuronal morphological level. These morphological changes involve loss of neurites due to cytoskeleton alterations. However, the mechanism of A beta(1-42) peptide activation of the neurodegenerative program is still poorly understood. Here, A beta(1-42) peptide-induced transduction of cellular death signals through the phosphatidylinositol 3-kinase (PI3K)/phosphoinositol- dependent kinase (PDK)/novel protein kinase C (nPKC)/Rac 1 axis is described. Furthermore, pharmacological inhibition of PDK1 and nPKC activities blocks Rac 1 activation and neuronal cell death. Our results provide insights into an unsuspected connection between PDK1, nPKCs and Rac 1 in the same signal-transduction pathway and points out nPKCs and Rac 1 as potential therapeutic targets to block the toxic effects of A beta(1-42) peptide in neurons.
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Background/Aims: In diabetic ventricular myocytes, transient outward potassium current (I-to) amplitude is severely reduced because of the impaired catecholamine release that characterizes diabetic autonomic neuropathy. Sympathetic nervous system exhibits a trophic effect on I-to since incubation of myocytes with noradrenaline restores current amplitude via beta-adrenoceptor (beta AR) stimulation. Here, we investigate the intracellular signalling pathway though which incubation of diabetic cardiomyocytes with the beta AR agonist isoproterenol recovers I-to amplitude to normal values. Methods: Experiments were performed in ventricular myocytes isolated from streptozotocin-diabetic rats. I-to current was recorded by using the patch-clamp technique. Kv4 channel expression was determined by immunofluorescence. Protein-protein interaction was determined by coimmunoprecipitation. Results: Stimulation of beta AR activates first a G alpha s protein, adenylyl cyclase and Protein Kinase A. PKA-phosphorylated receptor then switches to the G alpha i protein. This leads to the activation of the beta AR-Kinase-1 and further receptor phosphorylation and arrestin dependent internalization. The internalized receptor-arrestin complex recruits and activates cSrc and the MAPK cascade, where Ras, c-Raf1 and finally ERK1/2 mediate the increase in Kv4.2 and Kv4.3 protein abundance in the plasma membrane. Conclusion: beta(2)AR stimulation activates a G alpha s and G alpha i protein dependent pathway where the ERK1/2 modulates the Ito current amplitude and the density of the Kv4.2 and Kv4.2 channels in the plasma membrane upon sympathetic stimulation in diabetic heart.
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[EN] The purpose of this review article is to illustrate synthetic aspects of functionalized phosphorus derivatives containing an oximo moiety at the beta-position. First section will be focused on the synthesis of phosphine oxides, phosphonates or phosphonium salts containing an oxime group. The synthesis of these derivatives comprises the carbon–phosphorus single bond construction by reaction of haloximes with phosphorus derivatives, nucleophilic addition of phosphorus reagents to carbonyl compounds, or nucleophilic addition of phosphorus reagents to nitro olefins. This section will also concentrate on the most practical routes for the synthesis of the target compounds, through carbon–nitrogen double bond formation, which are as follows: condensation processes of carbonyl compounds and hydroxylamine derivatives or addition of hydroxylamines to allenes or alkynes. The preparative use of beta-oximo phosphorus derivatives as synthetic intermediates will be discussed in a second section, comprising olefination reaction, oxidation of oximes to nitrile oxides by reaction at the C-N double bond of the oxime moiety, oxidation of these substrates to nitrosoalkenes, reduction to the corresponding hydroxylamines and some reactions at the hydroxyl group of the hydroxyimino moiety.
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Hoy en día y con el objetivo de conseguir el mayor rendimiento posible en la mayoría de los deportes profesionales, la suplementación deportiva está adquiriendo un protagonismo vital, siendo conscientes de que la suplementación deportiva por sí sola no sea el principal factor responsable del aumento del rendimiento deportivo. Sin embargo, ha quedado demostrado que estos suplementos pueden ayudar a dar el salto de calidad en deportistas profesionales y últimamente salen a la luz investigaciones de nuevos suplementos que empiezan a ser habituales en algunos deportistas, como es el caso de la Beta-Alanina. El principal efecto de la ingesta exógena de b-alanina en el organismo radica en el aumento de la carnosina muscular debido a su rol como factor limitante en la síntesis de la misma, un dipéptido citoplasmático que tiene la capacidad de secuestrar los protones inducidos por el ejercicio de alta intensidad, retrasando la disminución del pH intramuscular y en consecuencia, retrasando la fatiga. La mayoría de los estudios hasta el momento que han investigado el efecto de la b-alanina y el rendimiento deportivo se centran en los deportes cíclicos, especialmente en aquellos deportes anaeróbicos donde la disminución del pH es limitante del rendimiento deportivo. Por ello, mediante una revisión bibliográfica el objetivo de este artículo será identificar y resumir los efectos principales de la suplementación exógena de Beta-alanina relacionados con el aumento del rendimiento deportivo y complementariamente, se realizar también un análisis sobre los factores fisiológicos del fútbol con el fin de conocer si este suplemento podría aumentar el rendimiento en los futbolistas de alto nivel.
Current Approaches for Predicting a Lack of Response to Anti-EGFR Therapy in KRAS Wild-Type Patients
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Targeting epidermal growth factor receptor (EGFR) has been one of the most effective colorectal cancer strategies. Anti-EGFR antibodies function by binding to the extracellular domain of EGFR, preventing its activation, and ultimately providing clinical benefit. KRAS mutations in codons 12 and 13 are recognized prognostic and predictive biomarkers that should be analyzed at the clinic prior to the administration of anti-EGFR therapy. However, still an important fraction of KRAS wild-type patients do not respond to the treatment. The identification of additional genetic determinants of primary or secondary resistance to EGFR targeted therapy for further improving the selection of patients is urgent. Herein, we review the latest published literature highlighting the most important genes that may predict resistance to anti-EGFR monoclonal antibodies in colorectal cancer patients. According to the available findings, the evaluation of BRAF, NRAS, PIK3CA, and PTEN status could be the right strategy to select patients who are likely to respond to anti-EGFR therapies. In the future, the combination of those biomarkers will help establish consensus that can be introduced into clinical practice.
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Comunicación (Poster) en panel del congreso: Designing New Heterogeneous Catalysts, Faraday Discussion, 4–6 April 2016. London, United Kingdom.
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Soil microbial community changes associated to conventional and organic farming of two relevant crops (Beta vulgaris and Solanum lycopersicum) were analysed through 16s rRNA amplicon sequencing. This study revealed microbial communities in the agricultural soils studied to be similar to other reported nutrient-rich microbiomes, and some significant differences between the microbial communities associated to the two farming practices were found. Some phyla (Chloroflexi and Thermi) were found to be present in different abundances according to soil treatment. As chloroplast interference can be a stumbling block in plant-associated 16s rRNA amplicon metagenomics analysis of aerial plant tissues, two protocols for bacterial cell detachment (orbital shaking and ultrasound treatment) and two protocols for microbial biomass recovery (centrifugation and filtration) were tested regarding their efficiency at excluding plant-DNA. An alternative method to the one proposed by Rastogi et al (2010) for evaluating the chloroplast-amplicon content in post-PCR samples was tested, and the method revealed that filtration was the most efficient protocol in minimising chloroplast interference.