503 research outputs found
Bayesian Deconvolution and Quantification of Metabolites from J-Resolved NMR Spectroscopy
Two-dimensional (2D) nuclear magnetic resonance (nmr) methods have become increasingly popular in metabolomics, since they have considerable potential to accurately identify and quantify metabolites within complex biological samples. 2D
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H J-resolved (jres) nmr spectroscopy is a widely used method that expands overlapping resonances into a second dimension. However, existing analytical processing methods do not fully exploit the information in the jres spectrum and, more importantly, do not provide measures of uncertainty associated with the estimates of quantities of interest, such as metabolite concentration. Combining the data-generating mechanisms and the extensive prior knowledge available in online databases, we develop a Bayesian method to analyse 2D jres data, which allows for automatic deconvolution, identification and quantification of metabolites. The model extends and improves previous work on one-dimensional nmr spectral data. Our approach is based on a combination of B-spline tight wavelet frames and theoretical templates, and thus enables the automatic incorporation of expert knowledge within the inferential framework. Posterior inference is performed through specially devised Markov chain Monte Carlo methods. We demonstrate the performance of our approach via analyses of datasets from serum and urine, showing the advantages of our proposed approach in terms of identification and quantification of metabolites
The need to transform Science Communication from being multi-cultural via cross-cultural to intercultural
When dealing with issues that are of high societal relevance, Earth sciences
still face a lack of acceptance, which is partly rooted in insufficient
communication strategies on the individual and local community level. To
increase the efficiency of communication routines, science has to transform
its outreach concepts to become more aware of individual needs and demands.
The āencoding/decodingā concept as well as critical intercultural
communication studies can offer pivotal approaches for this transformation.</p
Oxidative tyrosylation of high density lipoprotein by peroxidase enhances cholesterol removal from cultured fibroblasts and macrophage foam cells.
Upper critical field pecularities of superconducting YNi2B2C and LuNi2B2C
We present new upper critical field Hc2(T) data in a broad temperature region
from 0.3K to Tc for LuNi2B2C and YNi2B2C single crystals with well
characterized low impurity scattering rates. The absolute values for all T, in
particular Hc2(0), and the sizeable positive curvature (PC) of Hc2(T) at high
and intermediate T are explained quantitatively within an effective two-band
model. The failure of the isotropic single band approach is discussed in
detail. Supported by de Haas van Alphen data, the superconductivity reveals
direct insight into details of the electronic structure. The observed maximal
PC near Tc gives strong evidence for clean limit type II superconductors.Comment: 4 pages, 2 figures, Phys. Rev. Lett. accepte
Hydroclimate in the Pamirs Was Driven by Changes in PrecipitationāEvaporation Seasonality Since theLast Glacial Period
The Central Asian Pamir Mountains (Pamirs) are a highāaltitude region sensitive to climatic change, with only few paleoclimatic records available. To examine the glacialāinterglacial hydrological changes in the region, we analyzed the geochemical parameters of a 31ākyr record from Lake Karakul and performed a set of experiments with climate models to interpret the results. Ī“D values of terrestrial biomarkers showed insolationādriven trends reflecting major shifts of water vapor sources. For aquatic biomarkers, positive Ī“D shifts driven by changes in precipitation seasonality were observed at ca. 31ā30, 28ā26, and 17ā14 kyr BP. Multiproxy paleoecological data and modelling results suggest that increased water availability, induced by decreased summer evaporation, triggered higher lake levels during those episodes, possibly synchronous to northern hemispheric rapid climate events. We conclude that seasonal changes in precipitationāevaporation balance significantly influenced the hydrological state of a large waterbody such as Lake Karakul, while annual precipitation amount and inflows remained fairly constant
Bcl-xL Deamidation Is a Critical Switch in the Regulation of the Response to DNA Damage
AbstractThe therapeutic value of DNA-damaging antineoplastic agents is dependent upon their ability to induce tumor cell apoptosis while sparing most normal tissues. Here, we show that a component of the apoptotic response to these agents in several different types of tumor cells is the deamidation of two asparagines in the unstructured loop of Bcl-xL, and we demonstrate that deamidation of these asparagines imports susceptibility to apoptosis by disrupting the ability of Bcl-xL to block the proapoptotic activity of BH3 domain-only proteins. Conversely, Bcl-xL deamidation is actively suppressed in fibroblasts, and suppression of deamidation is an essential component of their resistance to DNA damage-induced apoptosis. Our results suggest that the regulation of Bcl-xL deamidation has a critical role in the tumor-specific activity of DNA-damaging antineoplastic agents
Serum Bilirubin and Ferritin Levels Link Heme Oxygenase-1 Gene Promoter Polymorphism and Susceptibility to Coronary Artery Disease in Diabetic Patients
OBJECTIVEāHeme oxygenase (HO) leads to the generation of free iron, carbon monoxide, and bilirubin. A length polymorphism of GT repeats in the promoter of human HO-1 gene has been shown to modulate gene transcription. The aim of this study was to assess the association of the length of (GT)n repeats in the HO-1 gene promoter with serum bilirubin, markers of iron status, and the development of coronary artery disease (CAD)
Neutrophil Extracellular TrapāDerived Enzymes Oxidize HighāDensity Lipoprotein: An Additional Proatherogenic Mechanism in Systemic Lupus Erythematosus
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108351/1/art38703.pd
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