@article{wang_ritter_kullman_muddiman_2023, title={Comparative analysis of sucrose-embedding for whole-body zebrafish MSI by IR-MALDESI}, volume={8}, ISSN={["1618-2650"]}, url={https://doi.org/10.1007/s00216-023-04914-1}, DOI={10.1007/s00216-023-04914-1}, journal={ANALYTICAL AND BIOANALYTICAL CHEMISTRY}, author={Wang, Mary F. and Ritter, Morgan M. and Kullman, Seth W. and Muddiman, David C.}, year={2023}, month={Aug} }
 @article{joignant_ritter_knizner_garrard_kullman_muddiman_2023, title={Maximized Spatial Information and Minimized Acquisition Time of Top-Hat IR-MALDESI-MSI of Zebrafish Using Nested Regions of Interest (nROIs)}, volume={8}, ISSN={["1879-1123"]}, DOI={10.1021/jasms.3c00210}, abstractNote={Increasing the spatial resolution of a mass spectrometry imaging (MSI) method results in a more defined heatmap of the spatial distribution of molecules across a sample, but it is also associated with the disadvantage of increased acquisition time. Decreasing the area of the region of interest to achieve shorter durations results in the loss of potentially valuable information in larger specimens. This work presents a novel MSI method to reduce the time of MSI data acquisition with variable step size imaging: nested regions of interest (nROIs). Using nROIs, a small ROI may be imaged at a higher spatial resolution while nested inside a lower-spatial-resolution peripheral ROI. This conserves the maximal spatial and chemical information generated from target regions while also decreasing the necessary acquisition time. In this work, the nROI method was characterized on mouse liver and applied to top-hat MSI of zebrafish using a novel optical train, which resulted in a significant improvement in both acquisition time and spatial detail of the zebrafish. The nROI method can be employed with any step size pairing and adapted to any method in which the acquisition time of larger high-resolution ROIs poses a practical challenge.}, journal={JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY}, author={Joignant, Alena N. and Ritter, Morgan M. and Knizner, Kevan T. and Garrard, Kenneth P. and Kullman, Seth W. and Muddiman, David C.}, year={2023}, month={Aug} }
 @article{knuth_stutts_ritter_garrard_kullman_2021, title={Vitamin D deficiency promotes accumulation of bioactive lipids and increased endocannabinoid tone in zebrafish}, volume={62}, ISSN={["1539-7262"]}, url={https://doi.org/10.1016/j.jlr.2021.100142}, DOI={10.1016/j.jlr.2021.100142}, abstractNote={Vitamin D is well known for its traditional role in bone mineral homeostasis; however, recent evidence suggests that vitamin D also plays a significant role in metabolic control. This study served to investigate putative linkages between vitamin D deficiency (VDD) and metabolic disruption of bioactive lipids by MS imaging. Our approach employed infrared-matrix-assisted laser desorption electrospray ionization MS imaging for lipid metabolite profiling in 6-month-old zebrafish fed either a VDD or a vitamin D-sufficient (VDS) diet. Using a lipidomics pipeline, we found that VDD zebrafish had a greater abundance of bioactive lipids (N-acyls, endocannabinoids [ECs], diacylglycerols/triacylglycerols, bile acids/bile alcohols, and vitamin D derivatives) suggestive of increased EC tone compared with VDS zebrafish. Tandem MS was performed on several differentially expressed metabolites with sufficient ion abundances to aid in structural elucidation and provide additional support for MS annotations. To confirm activation of the EC pathways, we subsequently examined expression of genes involved in EC biosynthesis, metabolism, and receptor signaling in adipose tissue and liver from VDD and VDS zebrafish. Gene expression changes were congruent with increased EC tone, with VDD zebrafish demonstrating increased synthesis and metabolism of anandamide compared with VDS zebrafish. Taken together, our data suggest that VDD may promote accumulation of bioactive lipids and increased EC tone in zebrafish.}, journal={JOURNAL OF LIPID RESEARCH}, publisher={Elsevier BV}, author={Knuth, Megan M. and Stutts, Whitney L. and Ritter, Morgan M. and Garrard, Kenneth P. and Kullman, Seth W.}, year={2021} }