Biomedical Engineering and Bioengineering Commons^™

Quantitative, Spectrally-Resolved Intraoperative Fluorescence Imaging, Pablo A. Valdés, Frederic Leblond, Valerie L. Jacobs, Brian C. Wilson, Keith D. Paulsen, David W. Roberts

Dartmouth Scholarship

Intraoperative visual fluorescence imaging (vFI) has emerged as a promising aid to surgical guidance, but does not fully exploit the potential of the fluorescent agents that are currently available. Here, we introduce a quantitative fluorescence imaging (qFI) approach that converts spectrally-resolved data into images of absolute fluorophore concentration pixel-by-pixel across the surgical field of view (FOV). The resulting estimates are linear, accurate, and precise relative to true values, and spectral decomposition of multiple fluorophores is also achieved. Experiments with protoporphyrin IX in a glioma rodent model demonstrate in vivo quantitative and spectrally-resolved fluorescence imaging of infiltrating tumor margins for the …

Rapid Temporal Changes In The Expression Of A Set Of Neuromodulatory Genes During Alcohol Withdrawal In The Dorsal Vagal Complex: Molecular Evidence Of Homeostatic Disturbance., Kate Freeman, Mary M. Staehle, Zeynep H Gümüş, Rajanikanth Vadigepalli, Gregory E Gonye, Carmen N Nichols, Babatunde A Ogunnaike, Jan B Hoek, James S Schwaber

Faculty Scholarship for the College of Science & Mathematics

BACKGROUND: Chronic alcohol exposure produces neuroadaptation, which increases the risk of cellular excitotoxicity and autonomic dysfunction during withdrawal. The temporal progression and regulation of the gene expression that contributes to this physiologic and behavioral phenotype is poorly understood early in the withdrawal period. Further, it is unexplored in the dorsal vagal complex (DVC), a brainstem autonomic regulatory structure.

METHODS: We use a quantitative polymerase chain reaction platform to precisely and simultaneously measure the expression of 145 neuromodulatory genes in more than 100 rat DVC samples from control, chronically alcohol-exposed, and withdrawn rats. To gain insight into the dynamic progression and …

Resting-State Connectivity Identifies Distinct Functional Networks In Macaque Cingulate Cortex., R Matthew Hutchison, Thilo Womelsdorf, Joseph S Gati, L Stan Leung, Ravi S Menon, Stefan Everling

Physiology and Pharmacology Publications

Subregions of the cingulate cortex represent prominent intersections in the structural networks of the primate brain. The relevance of the cingulate to the structure and dynamics of large-scale networks ultimately requires a link to functional connectivity. Here, we map fine-grained functional connectivity across the complete extent of the macaque (Macaca fascicularis) cingulate cortex and delineate subdivisions pertaining to distinct identifiable networks. In particular, we identified 4 primary networks representing the functional spectrum of the cingulate: somatomotor, attention-orienting, executive, and limbic. The cingulate nodes of these networks originated from separable subfields along the rostral-to-caudal axis and were characterized by positive and …

Quantitative Cherenkov Emission Spectroscopy For Tissue Oxygenation Assessment, Johan Axelsson, Adam K. Glaser, David J. Gladstone, Brian W. Pogue

Dartmouth Scholarship

Measurements of Cherenkov emission in tissue during radiation therapy are shown to enable estimation of hemoglobin oxygen saturation non-invasively, through spectral fitting of the spontaneous emissions from the treated tissue. Tissue oxygenation plays a critical role in the efficacy of radiation therapy to kill tumor tissue. Yet in-vivo measurement of this has remained elusive in routine use because of the complexity of oxygen measurement techniques. There is a spectrally broad emission of Cherenkov light that is induced during the time of irradiation, and as this travels through tissue from the point of the radiation deposition, the tissue absorption and scatter …

Methamphetamine Administration Targets Multiple Immune Subsets And Induces Phenotypic Alterations Suggestive Of Immunosuppression., Robert Z. Harms, Brenda M. Morsey, Craig W. Boyer, Howard S. Fox, Nora E. Sarvetnick

Journal Articles: Regenerative Medicine

Methamphetamine (Meth) is a widely abused stimulant and its users are at increased risk for multiple infectious diseases. To determine the impact of meth on the immune system, we utilized a murine model that simulates the process of meth consumption in a typical addict. Our phenotypic analysis of leukocytes from this dose escalation model revealed that meth affected key immune subsets. Meth administration led to a decrease in abundance of natural killer (NK) cells and the remaining NK cells possessed a phenotype suggesting reduced responsiveness. Dendritic cells (DCs) and Gr-1(high) monocytes/macrophages were also decreased in abundance while Gr-1(low) monocytes/macrophages appear …