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Volume 6, Issue 6(Suppl) J Clin Toxicol 2016
ISSN: 2161-0495, JCT an open access journal
Page 95
Notes:
Euro Toxicology 2016
October 24-26, 2016
conferenceseries.com
Toxicology & Applied Pharmacology
October 24-26, 2016 Rome, Italy
7th Euro-Global Summit on
X-ray fluorescence imaging in toxicology
Yulia Pushkar
Purdue University, USA
Atomic transitions in elements, including Mn, Fe, Cu, Zn, Pb relevant in toxicology can be excited upon interaction with
X-rays in 10-13 keV energy range. Recording resulting X-ray fluorescence (XRF) with high spatial resolution results in
quantitative images of metal ion distributions in tissue sections. Different X-ray focusing optics allows for tissue level imaging
(5-20 micron) resolution or subcellular level imaging (30-200 nm) of distributions of biologically relevant (Fe, Cu, Zn) and
toxic (Mn, Pb). Development of beamlines with high X-ray photon flux at 3rd generation synchrotron sources allows to
obtain high resolution XRF maps of ppm amounts of elements in thin tissue sections. Using XRF, we studied Mn distribution
in rat model of occupational Mn exposure. We found that globus pallidus and substantia nigra compacta are areas in the
brain that accumulate most Mn. Imaging the Mn distribution in dopaminergic neurons, we determined that intracellular Mn
range between 40–200 micromolar; concentrations as low as 100 micromolar have been observed to cause cell death in cell
cultures. This is a first direct link between Mn exposure and Parkinson’s disease. We have previously reported localized Cu-
rich aggregates in astrocytes of the subventricular zone in rodent brains with Cu concentrations in the hundreds of millimolar.
Based on a [S]/[Cu] ratio and X-ray absorption spectroscopy, metallothionein is proposed as a binding protein. An analysis of
metallothionein (1,2) knockout mice by XRF will be presented.
Biography
Yulia Pushkar has completed her PhD in Biophysics at Freie Universität Berlin, Germany and Post-doctoral studies at University of California, Berkeley & Lawrence
Berkeley National Lab. She is an Associate Professor of Physics and has published over 60 research articles including these in Science, Nature, Journal of
American Chemical Society and PNAS.
Yulia Pushkar, J Clin Toxicol 2016, 6:6(Suppl)