Search results for "F15"

Calibrating Expert Assessments Using Hierarchical Gaussian Process Models

2020

Expert assessments are routinely used to inform management and other decision making. However, often these assessments contain considerable biases and uncertainties for which reason they should be calibrated if possible. Moreover, coherently combining multiple expert assessments into one estimate poses a long-standing problem in statistics since modeling expert knowledge is often difficult. Here, we present a hierarchical Bayesian model for expert calibration in a task of estimating a continuous univariate parameter. The model allows experts' biases to vary as a function of the true value of the parameter and according to the expert's background. We follow the fully Bayesian approach (the s…

Hierarchical log Gaussian Cox process for regeneration in uneven-aged forests

2021

We propose a hierarchical log Gaussian Cox process (LGCP) for point patterns, where a set of points x affects another set of points y but not vice versa. We use the model to investigate the effect of large trees to the locations of seedlings. In the model, every point in x has a parametric influence kernel or signal, which together form an influence field. Conditionally on the parameters, the influence field acts as a spatial covariate in the intensity of the model, and the intensity itself is a non-linear function of the parameters. Points outside the observation window may affect the influence field inside the window. We propose an edge correction to account for this missing data. The par…

Transcriptomic profiling across the nonalcoholic fatty liver disease spectrum reveals gene signatures for steatohepatitis and fibrosis

2020

International audience; The mechanisms that drive nonalcoholic fatty liver disease (NAFLD) remain incompletely understood. This large multicenter study characterized the transcriptional changes that occur in liver tissue across the NAFLD spectrum as disease progresses to cirrhosis to identify potential circulating markers. We performed high-throughput RNA sequencing on a discovery cohort comprising histologically characterized NAFLD samples from 206 patients. Unsupervised clustering stratified NAFLD on the basis of disease activity and fibrosis stage with differences in age, aspartate aminotransferase (AST), type 2 diabetes mellitus, and carriage of PNPLA3 rs738409 , a genetic variant assoc…

Serum Concentration of Growth Differentiation Factor-15 Is Independently Associated with Global Platelet Function and Higher Fibrinogen Values in Adu…

2017

AbstractGrowth differentiation factor-15 (GDF-15) has recently emerged as a strong and independent predictor of cardiovascular events and mortality. However, the pathophysiological mechanisms underlying this important association remain speculative. This study was aimed to investigate the potential associations between the serum concentration of GDF-15 and clinical or laboratory parameters in a population of ostensibly healthy subjects. The study population consisted of 44 healthy volunteers enrolled from the laboratory staff (14 males and 30 females; mean age, 47 ± 11 years), who had their blood collected for assessing complete blood cell count, GDF-15, serum creatinine, albumin, cardiac t…

GDF 15 as an anti-apoptotic, diagnostic and prognostic marker in oral squamous cell carcinoma

2011

Growth-differentiation factor 15 (GDF 15) is involved in tumor pathogenesis and its expression is increased in many types of cancers. Functional effects of GDF 15 on oncogenesis of oral squamous cell carcinoma (OSCC) remain unclear. Therefore, the aim of this study was to examine the apoptotic characteristics of GDF 15 in OSCC cell lines in vitro and to analyze serum GDF 15 concentrations as a diagnostic and prognostic tumor marker for OSCC in vivo. Caspase activity was assessed in OSCC cell lines with the Caspase-Glo 3/7 system. Serum GDF 15 concentrations from 64 patients with histopathological proven OSCC and from 30 healthy volunteers were measured using an enzyme-linked immunosorbent a…

Biomarkers for characterization of heart failure - Distinction of heart failure with preserved and reduced ejection fraction.

2016

Heart failure (HF) incidence is rising worldwide and HF with preserved ejection fraction (HFpEF) represents nearly half of all cases. Treatment options are still limited in HFpEF in comparison to HF with reduced ejection fraction (HFrEF).We analyzed biomarkers in the general population to characterize HFpEF and HFrEF and defined a biomarker index to differentiate HFpEF from HFrEF. Growth differentiation factor-15 (GDF-15), soluble source of tumorigenicity 2 (sST2), C-reactive protein (CRP) and NT-proBNP were measured in 5000 individuals of the population-based Gutenberg Health Study (GHS). The median follow-up time for all-cause mortality was 7.3years with 213 events.Identification of subje…

Effects of acute exercise and xanthine oxidase inhibition on novel cardiovascular biomarkers.

2013

Several sports have been associated with a postexercise increase of cardiac, liver, and skeletal muscle biomarkers of injury. Exhaustive or acute physical exercise causes an increased generation of reactive oxygen species, resulting in cellular injury. Thus, exercise and training may trigger pathophysiological changes in serum concentrations of a variety of biomarkers. In this study, we aimed to evaluate the variation of novel biomarkers of stress and cardiovascular disease such as copeptin, midregional part of proadrenomedullin (MR-proADM), growth differentiation factor 15 (GDF15), soluble vascular endothelial growth factor receptor, and placental growth factor along with uric acid before …

Bayesian hierarchical models for analysing the spatial distribution of bioclimatic indices

2017

A methodological approach for modelling the spatial distribution of bioclimatic indices is proposed in this paper. The value of the bioclimatic index is modelled with a hierarchical Bayesian model that incorporates both structured and unstructured random effects. Selection of prior distributions is also discussed in order to better incorporate any possible prior knowledge about the parameters that could refer to the particular characteristics of bioclimatic indices. MCMC methods and distributed programming are used to obtain an approximation of the posterior distribution of the parameters and also the posterior predictive distribution of the indices. One main outcome of the proposal is the …

Genomic portrait of a sporadic amyotrophic lateral sclerosis case in a large spinocerebellar ataxia type 1 family

2020

Background: Repeat expansions in the spinocerebellar ataxia type 1 (SCA1) gene ATXN1 increases the risk for amyotrophic lateral sclerosis (ALS), supporting a relationship between these disorders. We recently reported the co-existence, in a large SCA1 family, of a clinically definite ALS individual bearing an intermediate ATXN1 expansion and SCA1 patients with a full expansion, some of which manifested signs of lower motor neuron involvement. Methods: In this study, we employed a systems biology approach that integrated multiple genomic analyses of the ALS patient and some SCA1 family members. Results: Our analysis identified common and distinctive candidate genes/variants and related biolog…

2021

Growth and differentiation factor 15 (GDF15) belongs to the transforming growth factor-β (TGF-β) superfamily of proteins. Glial-derived neurotrophic factor (GDNF) family receptor α-like (GFRAL) is an endogenous receptor for GDF15 detected selectively in the brain. GDF15 is not normally expressed in the tissue but is prominently induced by “injury”. Serum levels of GDF15 are also increased by aging and in response to cellular stress and mitochondrial dysfunction. It acts as an inflammatory marker and plays a role in the pathogenesis of cardiovascular diseases, metabolic disorders, and neurodegenerative processes. Identified as a new heart-derived endocrine hormone that regulates body growth,…