Summary: | Thesis (M.A.)--Boston University
PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at open-help@bu.edu. Thank you. === The purpose of this study was to suggest a novel and simple approach to imaging and quantifying wounds in mice using a fluorescence molecular imaging technique. By intravenously injecting molecular probes into lipopolysaccharide-positive mice and lipopolysaccharide-negative mice, the capability of fluorescence reflectance imaging in describing the degree of wound injury was investigated. To observe and quantify mouse wound healing in mice, two imaging systems , OV110 (Olympus America, Center Valley, PA) and Fluorescence Molecular Tomography (Visen, Bedford, MA) were utilized along with a target-specific probe, which was to be vi sualized at a specific wavelength channel. A standardized wound on the dorsum of each mouse was created using a 6mm punch biopsy, and donut-shaped splint was sutured around it to prevent contraction of the wound region. On day 0, day 1, day 4, and day 7, two groups of mice with different interventions were imaged with identical imaging settings. Change in wound size and fluorescence concentration was then statistically analyzed at the end of experiment. Measurement of fluorescence concentration with two different imaging systems generated consistent data over the course of imaging. In both groups, the peak fluorochrome concentration was observed on day 4, at which point the inflammatory response is considered to be most active. In the OV110 imaging, the target-to-background ratio of fluorescence concentration, which represents net probe activation level at the wound site, was consistently higher in the LPS-injected group over 7 days. A significant difference in mean ratio value was observed on day 4 with a p-value equal to 0.0062. Similar results from FMT imaging confirm the OV110 data. In both groups, mean concentration at the wound site increased until it reached a peak concentration on day 4, after which the value decreased. The mean concentration in LPS-injected mice and non-injected mice were significantly different on day 4 and day 7 with p-values equal to 0.044 and 0 .016 respectively. The wound healing rate reflected by the percentage wound area relative to original wound size was slower in the LPS-injected group. On day 7, LPS-injected mice had 78.18% of the original wound remained open. Non-injected mice had 52.27% of the original wound site open on day 7. This would indicate that LPS is a significant factor, which enhances the overall extent of the inflammatory response in the wound healing process while simultaneously impeding the rate of wound closure considerably.
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