Office of Research and Development Publications

Records 1 to 25 of 727

CHEMICAL PRIORITIZATION FOR DEVELOPMENTAL TOXICITY USING LITERATURE MINING-BASED WEIGHTING OF TOXCAST ASSAYS (PRESENTATION)
Defining a predictive model of developmental toxicity from in vitro and high-throughput screening (HTS) assays can be limited by the availability of developmental defects data. ToxRefDB (www.epa.gov/ncct/todrefdb) was built from animal studies on data-rich environmental chemicals...
(BOSC) DOSE-RESPONSE MODELING FOR THE ASSESSMENT OF CUMULATIVE RISK DUE TO EXPOSURE TO N-METHYL CARBAMATE PRESTICIDES (PRESENTATION)
THE US EPA'S N-METHYL CARBAMATE CUMULATIVE RISK ASSESSMENT (NMCRA) ASSESSES THE EFFECT ON ACETYLCHOLINE ESTERASE (AChE) ACTIVITY OF EXPOSURE TO 10 N-METHLY CARBAMATE (NMC)PESTICIDES THROUGH DIETARY, DRINKING WATER, AND RESIDENTIAL EXPOSURES. THESE DATA THUS INFORM, BUT DO NOT COM...
(ISEA) IDENTIFYING IMPORTANT FACTORS INFLUENCING CHILDREN'S EXPOSURES TO PESTICIDES (PRESENTATION)
Template for symposia abstracts submission; requirements for symposium organisers.(European Spelling)
(WISCONSIN) OVERVIEW OF US EPA RESEARCH ACTIVITIES AIMED AT CHARACTERIZING CHILDRENS EXPOSURES (PRESENTATION)
Overview of significant research activities that have been initiated by the USEPA to increase understanding of children’s vulnerabilities and to better characterize children’s exposures to chemical stressors.
*Comparative pharmacokinetics of perfluorononanoic acid in rats and mice (PRESENTATION)
Perfluorononanoic acid (PFNA), a member of the perfluoroalkyl acids (PFAAs) is found at low concentrations in the environment, but detectable in humans and wildlife. Previous studies have examined the pharmacokinetics (PK) of shorter carbon-chain PFAAs, such as perfluorobutyric a...
2008 HESI Emerging Issue: Identification of Pharmaceuticals for Validation of ToxCast (PRESENTATION)
Slide presentation to discuss identification of pharmaceuticals for validation of ToxCast.
2009 International Workshop on Virtual Tissues (PRESENTATION)
Internal presentation on how virtual tissues will improve understanding of molecular and cellular pathways to efficiently analyze thousands of environmental contaminants.
20150323 - The U.S. EPA ToxCast Program: Moving from Data Generation to Application (SOT Tox21 update symposium presentation) (PRESENTATION)
The U.S. EPA ToxCast program is entering its tenth year. Significant learning and progress have occurred towards collection, analysis, and interpretation of the data. The library of ~1,800 chemicals has been subject to ongoing characterization (e.g., identity, purity, stability...
20150325 - Application of High-Throughput In Vitro Assays for Risk-Based Chemical Safety Decisions of Environmental and Industrial Chemicals (SOT presentation) (PRESENTATION)
Multiple drivers shape the types of human-health assessments performed on chemicals by U.S. EPA resulting in chemical assessments are “fit-for-purpose” ranging from prioritization for further testing to full risk assessments. Layered on top of the diverse assessment n...
20150503 - Tutorial Video Series: Using Stakeholder Outreach to Increase Usage of ToxCast Data (SETAC EU) (PRESENTATION)
The limited amount of toxicity data on thousands of chemicals found in consumer products has led to the development of research endeavors such as the U.S. EPA’s Toxicity Forecaster (ToxCast). ToxCast uses high-throughput screening technology to evaluate thousands of chemica...
A BIOLOGIST'S PERSPECTIVE ON)ESTIMATING LOW-DOSE RISK FROM HIGH-DOSE DATA AND ITS ASSOCIATED UNCERTAINTY (PRESENTATION)
Risk at a given exposure is determined by biological processes.
A Balanced Accuracy Fitness Function Leads to Robust Analysis Using Grammatical Evolution Neural Networks in the Case of Class Imbalance (PRESENTATION)
The identification and characterization of genetic and environmental factors that predict common, complex disease is a major goal of human genetics. The ubiquitous nature of epistatic interaction in the underlying genetic etiology of such disease presents a difficult analytical ...
A Biologically Informed Framework for the Analysis of the PPAR Signaling Pathway using a Bayesian Network (PRESENTATION)
The US EPA’s ToxCastTM program seeks to combine advances in high-throughput screening technology with methodologies from statistics and computer science to develop high-throughput decision support tools for assessing chemical hazard and risk. To develop new methods of analysis of...
A Boolean Network Model of Nuclear Receptor Mediated Cell Cycle Progression (PRESENTATION)
Nuclear receptors (NRs) are ligand-activated transcription factors that regulate a broad range of cellular processes. Hormones, lipids and xenobiotics have been shown to activate NRs with a range of consequences on development, metabolism, oxidative stress, apoptosis, and prolif...
A Boolean Network Model of Nuclear Receptor Mediated Cell Cycle Progression (S) (PRESENTATION)
Nuclear receptors (NRs) are ligand-activated transcription factors that regulate a broad range of cellular processes. Hormones, lipids and xenobiotics have been shown to activate NRs with a range of consequences on development, metabolism, oxidative stress, apoptosis, and prolif...
A Call for Nominations of Quantitative High-Throughput Screening Assays from Relevant Human Toxicity Pathways (PRESENTATION)
The National Research Council of the United States National Academies of Science has recently released a document outlining a long-range vision and strategy for transforming toxicity testing from largely whole animal-based testing to one based on in vitro assays. “Toxicity Testin...
A Collaborative Web-Based Architecture For Sharing ToxCast Data (PRESENTATION)
Collaborative Drug Discovery (CDD) has created a scalable platform that combines traditional drug discovery informatics with Web2.0 features. Traditional drug discovery capabilities include substructure, similarity searching and export to excel or sdf formats. Web2.0 features inc...
A Computational Framework for Systems-based Analysis of Developmental Toxicity (PRESENTATION)
Discusses the EPA/NCCT ToxRefDB database. The EPA is building capacity for multi-dimensional evaluation of toxicity using information aboout chemical properties, genome-wide responses, and cell-based assays.
A Data Repository and Visualization Toolbox for Metabolic Pathways and PBPK parameter prediction (PRESENTATION)
NHANES is an extensive, well-structured collection of data about hundreds chemicals products of human metabolism and their concentration in human biomarkers, which includes parent to product mapping where known. Together, these data can be used to test the efficacy of application...
A Developmental Toxicity Database to Support Computational Toxicology; A Collaborative Project for Data Sharing and Harmonization (PRESENTATION)
Developmental toxicity is one of the most important non-cancer endpoints for both environmental and human health. Despite the fact that numerous developmental studies are being conducted, as required for regulatory decisions, there are not yet sufficient data available to develop...
A General Approach for Specifying Informative Prior Distributions for PBPK Model Parameters (PRESENTATION)
Characterization of uncertainty in model predictions is receiving more interest as more models are being used in applications that are critical to human health. For models in which parameters reflect biological characteristics, it is often possible to provide estimates of paramet...
A MAPPING BASED ON PHYSICO-CHEMICAL FEATURES: LESSONS LEARNT (PRESENTATION)
The ban on animal testing of cosmetic products for systemic toxicity in Europe is foreseen in 2013. Several research programs involving the public and private sectors have been initiated with the aim of fulfilling regulatory requirements and complying with this transformative shi...
A MODE-OF-ACTION-BASED QSAR APPROACH TO IMPROVE UNDERSTANDING OF DEVELOPMENTAL TOXICITY (PRESENTATION)
QSAR models of developmental toxicity (devtox) have met with limited regulatory acceptance due to the use of ill-defined endpoints, lack of biological interpretability, and poor model performance. More generally, the lack of biological inference of many QSAR models is often due t...
A Model for Micro-Dosimetry in Virtual Liver Tissues (PRESENTATION)
Motivation: Humans are potentially exposed to over 6,000 environmental chemicals. The liver is the primary organ for metabolism and often the first site of chemical-induced toxicity in animal testing, but it remains difficult to translate these outcomes to humans. To address thi...
A PHARMACOKINETIC PROGRAM (PKFIT) FOR R (PRESENTATION)
The purpose of this study was to create a nonlinear regression (including a genetic algorithm) program (R script) to deal with data fitting for pharmacokinetics (PK) in R environment using its available packages. We call this tool as PKfit.