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NCTR Research Highlights

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Current Highlight from April 10, 2015

Confirmation of Mutations Detected by Pig-a Assay

NCTR scientists have established a direct connection between the GPI-anchored surface marker deficiency detected by the Pig-a assay and mutations in the Pig-a gene in rat t cells.  Rats were treated with a model mutagen, N-ethyl-N-nitrosourea (ENU) which induced lymphocytes with altered cell surface markers (i.e., mutant phenotype). Molecular analysis of these cells revealed mutations in the endogenous X-linked Pig-a gene. The spectrum of the Pig-a mutation was consistent with the types of mutations produced by ENU in other in vivo models.  The Pig-a assay, developed through a collaboration between FDA/NCTR, the pharmaceutical industry, and contract research organizations, is a novel flow cytometry-based assay for identifying potential mutagens in vivo and may have utility in more comprehensive toxicity assessments of FDA-regulated products.  A manuscript describing the results of this study is now available online at Mutagenesisdisclaimer icon

For additional information, please contact Vasily Dobrovolsky, Ph.D., Division of Genetic and Molecular Toxicology, FDA/NCTR.

A Simple Procedure for the Isolation and Characterization of Nanomaterials in Dietary Supplements

Nanotechnology Core Facility scientists from the Office of Regulatory Affairs and NCTR developed methods to separate and characterize silicon dioxide and titanium dioxide nanoparticles commonly added to dietary supplements.  Twelve commercially available dietary supplement products were subjected to an acid digestion and centrifugation method to isolate nanoparticles from the product, and the resulting nanomaterials were characterized with a battery of standard techniques.  These methods are expected to be adaptable to the isolation and characterization of these nanomaterials from multiple FDA-regulated products.  This work was supported in part by the FDA Office of Women’s Health.  A manuscript describing the study is available online at Journal of Agricultural and Food Chemistrydisclaimer icon.

For additional information, please contact Sean Linder, FDA/ORA, or Paul Howard, Director, Office of Scientific Coordination, FDA/NCTR.


Contact FDA

National Center for Toxicological Research

Food and Drug Administration

3900 NCTR Road

Jefferson, AR 72079

Page Last Updated: 04/16/2015
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