OMPI Seminar: Chad Hunter, Dmitry Klokov and Yi Wang

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Date: 
Thursday, October 22, 2015

Time: 3:30-5:00 pm - Thursday 22 October 2015. Refreshments start at 3:15 pm.

Location: Room RPB 205 (boardroom), Health Canada, 775 Brookfield Road Carleton University.

Presentations:

1. Motion correction in Positron Emission Tomography (PET) imaging

By Chad Hunter, Carleton University and The University of Ottawa Heart Institute.

Abstract: Patient motion is a common problem during dynamic PET scans for quantification of myocardial blood flow (MBF).  Computer simulation studies indicate that errors in MBF can approach 500 % for scans with severe patient motion. Motion correction algorithms should be effective in identifying mid- and late-time-frame motion, and motion in the left/right direction, since these cases produce the largest errors in MBF, particularly for high resolution PET imaging.  A post reconstruction image-based method, and a pre reconstruction projection-based method for detecting and correcting patient motion was developed and evaluated.

 

2. Rejuvenating effect of low dose gamma-radiation on blood immunological parameters: Evidence for mice vs. human

By Dmitry Klokov and Yi Wang, Canadian Nuclear Laboratories.

Abstract: Our previous results indicated that low dose gamma-radiation may delay the onset of cellular senescence/aging in an in vitro model of normal human fibroblasts. We extended this result into an in vivo mouse study wherein we examined various immunological and DNA damage and repair parameters in C57Bl6/J mice. We compared responses to 10 mGy of gamma-radiation in 2-months old (young) with those in 26-months old (aged) mice. We found that responses in aged mice were in general more pronounced. An aged related shift in levels of blood cytokines (16 cytokines screened) was observed in non-exposed mouse groups. Strikingly, 2 weeks after 10 mGy dose, levels of 6 cytokines in aged mice were reversed back to the levels observed in young non-irradiated control mice. This rejuvenating effect of low dose gamma-radiation on immunological blood cytokine levels required further verification using functional immunological assays in mice, as well as in human patients undergoing low dose diagnostic irradiations.