785 research outputs found
Big-data, a digital ocean in the Information Society
Inmersos en la revolución digital, generamos constantemente datos y la mayoría son almacenados. Es lo que se ha denominado los “datos grandes” o Big-data. Junto con el capital y la fuerza de trabajo, los datos se han convertido en un valor añadido para la economía que refleja un futuro con un paradigma revolucionario en el que la sociedad será dirigida por los datos. El futuro está en la investigación, tratamiento y aplicación de los datos que aportarán prosperidad a nuestra sociedad. En el presente artículo se recogen las normas y leyes que existen hoy en día en el Big-data y la regulación existente. Para analizar Big-data la solución pasa por el aprendizaje automático (Machine-Learning) que se ocupa de la construcción y el estudio de los algoritmos que pueden aprender a partir de datos. Existen muchas técnicas, como estadística descriptiva, clasificación o agrupamiento. En este artículo se recoge las tecnologías que se utilizan para almacenar y analizar los “Big-data”.Immersed in the digital revolution, we generate data consistently and most are stored. This is what has been called the Big-data. Along with capital and labor force data have become an added value to the economy that reflects a future with a revolutionary paradigm in which society will be directed by the data. The future is in research, treatment and application data that will bring prosperity to our society. In this article the rules and laws that exist today in the Big-data and existing regulations are collected. To analyze the Big-data passes through the machine learning that deals with the construction and study of algorithms that can learn from data solution. There are many techniques such as descriptive statistics, sorting or grouping. This article describes the technologies that are used to store and analyze the “Big data” is collected
Conformation and concerted dynamics of the integrin-binding site and the C-terminal region of echistatin revealed by homonuclear NMR
Echistatin is a potent antagonist of the integrins αvβ3, α5β1 and
αIIbβ3. Its full inhibitory activity depends on an RGD (Arg-Gly-
Asp) motif expressed at the tip of the integrin-binding loop and on
its C-terminal tail. Previous NMR structures of echistatin showed
a poorly defined integrin-recognition sequence and an incomplete
C-terminal tail, which left the molecular basis of the functional
synergy between the RGD loop and the C-terminal region unresolved.
We report a high-resolution structure of echistatin and
an analysis of its internal motions by off-resonance ROESY
(rotating-frame Overhauser enhancement spectroscopy). The fulllength
C-terminal polypeptide is visible as a β-hairpin running
parallel to the RGD loop and exposing at the tip residues Pro43,
His44 and Lys45. The side chains of the amino acids of the RGD
motif have well-defined conformations. The integrin-binding loop
displays an overall movement with maximal amplitude of 30◦.
Internal angular motions in the 100–300 ps timescale indicate
increased flexibility for the backbone atoms at the base of the integrin-
recognition loop. In addition, backbone atoms of the
amino acids Ala23 (flanking the R24GD26 tripeptide) and Asp26
of the integrin-binding motif showed increased angular mobility,
suggesting the existence of major and minor hinge effects at the
base and the tip, respectively, of the RGD loop. A strong network
of NOEs (nuclear Overhauser effects) between residues of the
RGD loop and the C-terminal tail indicate concerted motions
between these two functional regions. A full-length echistatin–
αvβ3 docking model suggests that echistatin’s C-terminal amino
acids may contact αv-subunit residues and provides new insights
to delineate structure–function [email protected]; [email protected]; [email protected]; [email protected]
Peripheral blood mitochondrial DNA content in relation to circulating metabolites and inflammatory markers: a population study
Mitochondrial DNA (mtDNA) content might undergo significant changes caused by metabolic derangements, oxidative stress and inflammation that lead to development and progression of cardiovascular diseases. We, therefore, investigated in a general population the association of peripheral blood mtDNA content with circulating metabolites and inflammatory markers. We examined 310 subjects (50.6% women; mean age, 53.3 years) randomly selected from a Flemish population. Relative mtDNA content was measured by quantitative real-time PCR in peripheral blood cells. Peak circulating metabolites were quantified using nuclear magnetic resonance spectroscopy. The level of inflammation was assessed via established inflammatory markers. Using Partial Least Squares analysis, we constructed 3 latent factors from the 44 measured metabolites that explained 62.5% and 8.5% of the variance in the contributing metabolites and the mtDNA content, respectively. With adjustments applied, mtDNA content was positively associated with the first latent factor (P = 0.002). We identified 6 metabolites with a major impact on the construction of this latent factor including HDL3 apolipoproteins, tyrosine, fatty acid with αCH2, creatinine, β-glucose and valine. We summarized them into a single composite metabolite score. We observed a negative association between the composite metabolic score and mtDNA content (P = 0.001). We also found that mtDNA content was inversely associated with inflammatory markers including hs-CRP, hs-IL6, white blood cell and neutrophil counts as well as neutrophil-to-lymphocyte ratio (P≤0.0024). We demonstrated that in a general population relative peripheral blood mtDNA content was associated with circulating metabolites indicative of perturbed lipid metabolism and with inflammatory biomarkers
Metabolic Profile of chronic liver disease by NMR spectroscopy of human biopsies
Abstract Among the different processes occurring during the evolution of liver disease, fibrosis has a predominant role. Liver fibrosis mechanisms are fairly constant irrespective of the underlying etiology. Cirrhosis is the end-stage of this reaction. Metabolic profiles, which are affected by many physiological and pathological processes, may provide further insight into the metabolic consequences of this severe liver disease. The aim of this study was to demonstrate the applicability of 1H high resolution magic angle spinning (HR-MAS) NMR spectroscopy in the biochemical profile determination of human liver needle biopsy samples for the characterization of metabolic alterations related to the severity of liver disease. We recorded and analyzed HR-MAS spectra of 68 liver tissue samples obtained by needle biopsy from patients with chronic liver disease. Multivariate analysis was applied to these data to obtain discrimination patterns and to reveal relevant metabolites. The metabolic characterization of liver tissue from needle biopsies by HR-MAS NMR spectroscopy provided differential patterns for cirrhotic and non-cirrhotic chronic liver disease tissue. Metabolites closely related to the liver metabolism such as some fatty acids, glucose and amino acids show differences between the two groups. Phospholipid precursors, which have been previously correlated with hepatic lesions also show differences. Furthermore, the correlation between histologically assessed liver disease stages and the levels of the most discriminative metabolites show that liver dysfunction is present at the initial stages of chronic hepatic lesions. Overall, this work suggests that the additional information obtained by NMR metabolomics applied to needle biopsies of human liver may be useful for assessing metabolic alterations and liver dysfunction in chronic liver disease
Convex non-negative matrix factorization for brain tumor delimitation from MRSI data
Background: Pattern Recognition techniques can provide invaluable insights in the field of neuro-oncology. This is because the clinical analysis of brain tumors requires the use of non-invasive methods that generate complex data in electronic format. Magnetic Resonance (MR), in the modalities of spectroscopy (MRS) and spectroscopic imaging (MRSI), has been widely applied to this purpose. The heterogeneity of the tissue in the brain volumes analyzed by MR remains a challenge in terms of pathological area delimitation. Methodology/Principal Findings: A pre-clinical study was carried out using seven brain tumor-bearing mice. Imaging and spectroscopy information was acquired from the brain tissue. A methodology is proposed to extract tissue type-specific sources from these signals by applying Convex Non-negative Matrix Factorization (Convex-NMF). Its suitability for the delimitation of pathological brain area from MRSI is experimentally confirmed by comparing the images obtained with its application to selected target regions, and to the gold standard of registered histopathology data. The former showed good accuracy for the solid tumor region (proliferation index (PI)>30%). The latter yielded (i) high sensitivity and specificity in most cases, (ii) acquisition conditions for safe thresholds in tumor and non-tumor regions (PI>30% for solid tumoral region; ≤5% for non-tumor), and (iii) fairly good results when borderline pixels were considered. Conclusions/Significance: The unsupervised nature of Convex-NMF, which does not use prior information regarding the tumor area for its delimitation, places this approach one step ahead of classical label-requiring supervised methods for discrimination between tissue types, minimizing the negative effect of using mislabeled voxels. Convex-NMF also relaxes the non-negativity constraints on the observed data, which allows for a natural representation of the MRSI signal. This should help radiologists to accurately tackle one of the main sources of uncertainty in the clinical management of brain tumors, which is the difficulty of appropriately delimiting the pathological area
Triple-negative breast cancer: Present challenges and new perspectives
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Healthy lifestyle, metabolomics and incident type 2 diabetes in a population-based cohort from Spain
This work was supported by the Strategic Action for Research in Health sciences [PI10/0082, PI13/01848, PI14/00874, PI16/01402, PI11/00726, PI16/609, PI16/1512, PI18/287, PI19/319 and PI20/00896], the GUTMOM Project (JPI-A Healthy Diet for a Healthy Life INTIMIC-085, State Secretary of R + D + I PCIN-2017-117), the Cátedra de Epidemiología y Control del Riesgo Cardiovascular at UAM (#820024), the State Agency for Research (PID2019-108973RB-C21 and C22), the Valencia Government (GRUPOS 03/101; PROMETEO/2009/029 and ACOMP/2013/039), the Castilla-Leon Government (GRS/279/A/08) and European Network of Excellence Ingenious Hypercare (EPSS- 037093) from the European Commission; CIBER Fisiopatología Obesidad y Nutrición (CIBEROBN) (CIBER-02-08-2009, CB06/03 and CB12/03/30016). MSP holds a Ramón y Cajal contract (RYC-2018-025069-I) from the Ministry of Science, Innovation and Universities. MDV holds a “Predoctoral Training in Health Research” contract (FI20/00162) from the Carlos III Health Institute. MGP and ADR received the support of a fellowship from “la Caixa” Foundation (ID 100010434, fellowship codes LCF/BQ/IN18/11660001, and LCF/BQ/DR19/11740016, respectively). PO received the support of a Sara Borrell contract from the Carlos III Health Institute (reference CD16/00255). The Strategic Action for Research in Health Sciences, CIBEROBN are initiatives from Carlos III Health Institute Madrid and co-funded by the European Social Fund “The ESF - investing in your future”. The State Agency for Research and Carlos III Health Institute belong to the Spanish Ministry of Science and Innovation. The funding bodies had no role in the study design, data collection and analysis, interpretation of results, manuscript preparation or in the decision to submit this manuscript for publication.Background: The contribution of metabolomic factors to the association of healthy lifestyle with type 2 diabetes risk is unknown. We assessed the association of a composite measure of lifestyle with plasma metabolite profiles and incident type 2 diabetes, and whether relevant metabolites can explain the prospective association between healthy lifestyle and incident type 2 diabetes. Methods: A Healthy Lifestyle Score (HLS) (5-point scale including diet, physical activity, smoking status, alcohol consumption and BMI) was estimated in 1016 Hortega Study participants, who had targeted plasma metabolomic determinations at baseline examination in 2001–2003, and were followed-up to 2015 to ascertain incident type 2 diabetes. Results: The HLS was cross-sectionally associated with 32 (out of 49) plasma metabolites (2.5% false discovery rate). In the subset of 830 participants without prevalent type 2 diabetes, the rate ratio (RR) and rate difference (RD) of incident type 2 diabetes (n cases = 51) per one-point increase in HLS was, respectively, 0.69 (95% CI, 0.51, 0.93), and − 8.23 (95% CI, − 16.34, − 0.13)/10,000 person-years. In single-metabolite models, most of the HLS-related metabolites were prospectively associated with incident type 2 diabetes. In probit Bayesian Kernel Machine Regression, these prospective associations were mostly driven by medium HDL particle concentration and phenylpropionate, followed by small LDL particle concentration, which jointly accounted for ~ 50% of the HLS-related decrease in incident type 2 diabetes. Conclusions: The HLS showed a strong inverse association with incident type 2 diabetes, which was largely explained by plasma metabolites measured years before the clinical diagnosis.CIBER Fisiopatología Obesidad y NutriciónCastilla-Leon Government
GRS/279/A/08European Network of Excellence Ingenious Hypercare
EPSS- 037093State Agency for Research
ACOMP/2013/039, GRUPOS 03/101, PROMETEO/2009/029Strategic Action for Research in Health sciences
INTIMIC-085, PCIN-2017-117Ministerio de Ciencia, Innovación y Universidades
RYC-2018-025069-IEuropean Commission
EPSS-037093Instituto de Salud Carlos III
CB06/03, CB12/03/30016, CD16/00255, CIBER-02-08-2009, PI10/0082, PI11/00726, PI13/01848, PI14/00874, PI16/01402, PI16/1512, PI16/609, PI18/287, PI19/319, PI20/00896Universidad Autónoma de Madrid 820024Agencia Estatal de Investigación
PID2019-108973RB-C21“La Caixa” Foundation 100010434, LCF/BQ/DR19/11740016, LCF/BQ/IN18/1166000
Neurochemical Changes in the Mouse Hippocampus Underlying the Antidepressant Effect of Genetic Deletion of P2X7 Receptors.
Recent investigations have revealed that the genetic deletion of P2X7 receptors (P2rx7) results in an antidepressant phenotype in mice. However, the link between the deficiency of P2rx7 and changes in behavior has not yet been explored. In the present study, we studied the effect of genetic deletion of P2rx7 on neurochemical changes in the hippocampus that might underlie the antidepressant phenotype. P2X7 receptor deficient mice (P2rx7-/-) displayed decreased immobility in the tail suspension test (TST) and an attenuated anhedonia response in the sucrose preference test (SPT) following bacterial endotoxin (LPS) challenge. The attenuated anhedonia was reproduced through systemic treatments with P2rx7 antagonists. The activation of P2rx7 resulted in the concentration-dependent release of [3H]glutamate in P2rx7+/+ but not P2rx7-/- mice, and the NR2B subunit mRNA and protein was upregulated in the hippocampus of P2rx7-/- mice. The brain-derived neurotrophic factor (BDNF) expression was higher in saline but not LPS-treated P2rx7-/- mice; the P2rx7 antagonist Brilliant blue G elevated and the P2rx7 agonist benzoylbenzoyl ATP (BzATP) reduced BDNF level. This effect was dependent on the activation of NMDA and non-NMDA receptors but not on Group I metabotropic glutamate receptors (mGluR1,5). An increased 5-bromo-2-deoxyuridine (BrdU) incorporation was also observed in the dentate gyrus derived from P2rx7-/- mice. Basal level of 5-HT was increased, whereas the 5HIAA/5-HT ratio was lower in the hippocampus of P2rx7-/- mice, which accompanied the increased uptake of [3H]5-HT and an elevated number of [3H]citalopram binding sites. The LPS-induced elevation of 5-HT level was absent in P2rx7-/- mice. In conclusion there are several potential mechanisms for the antidepressant phenotype of P2rx7-/- mice, such as the absence of P2rx7-mediated glutamate release, elevated basal BDNF production, enhanced neurogenesis and increased 5-HT bioavailability in the hippocampus
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