Saint Louis University View Institution's Website 16 articles published in JoVE Chemistry Versatile Technique to Produce a Hierarchical Design in Nanoporous Gold Palak Sondhi1, Dharmendra Neupane1, Jay K. Bhattarai2, Hafsah Ali1, Alexei V. Demchenko3, Keith J. Stine1 1Department of Chemistry and Biochemistry, University of Missouri-Saint Louis, 2Mallinckrodt Pharmaceuticals Company, 3Department of Chemistry, Saint Louis University Nanoporous gold with a hierarchical and bimodal pore size distribution can be produced by combining electrochemical and chemical dealloying. The composition of the alloy can be monitored via EDS-SEM examination as the dealloying process advances. The material's loading capacity can be determined by studying protein adsorption onto the material. Immunology and Infection Isolation and Quantification of Zika Virus from Multiple Organs in a Mouse James D. Brien*1, Mariah Hassert*1, E. Taylor Stone1, Elizabeth Geerling1, Lillian Cruz-Orengo2, Amelia K. Pinto1 1Department of Molecular Microbiology and Immunology, Saint Louis University, 2School of Veterinary Medicine University of California Davis The goal of the protocol is to demonstrate the techniques used to investigate viral disease by isolating and quantifying Zika virus, from multiple organs in a mouse following infection. Environment Sampling, Sorting, and Characterizing Microplastics in Aquatic Environments with High Suspended Sediment Loads and Large Floating Debris Katherine M. Martin1, Elizabeth A. Hasenmueller2, John R. White3, Lisa G. Chambers4, Jeremy L. Conkle1 1Department of Physical and Environmental Sciences, Texas A&M University-Corpus Christi, 2Department of Earth and Atmospheric Sciences, Saint Louis University, 3Department of Oceanography and Coastal Sciences, Louisiana State University, 4Department of Biology, University of Central Florida Most microplastic research to date has occurred in marine systems where suspended solid levels are relatively low. Focus is now shifting to freshwater systems, which may feature high sediment loads and floating debris. This protocol addresses collecting and analyzing microplastic samples from aquatic environments that contain high suspended solid loads. Biochemistry Measuring Trans-Plasma Membrane Electron Transport by C2C12 Myotubes Shannon C. Kelly*1, Amanda M. Eccardt*1, Jonathan S. Fisher1 1Department of Biology, Saint Louis University The goal of this protocol is to spectrophotometrically monitor trans-plasma membrane electron transport utilizing extracellular electron acceptors and to analyze enzymatic interactions that may occur with these extracellular electron acceptors. Bioengineering Simple Polyacrylamide-based Multiwell Stiffness Assay for the Study of Stiffness-dependent Cell Responses Sana Syed1, Amin Karadaghy1, Silviya Zustiak1 1Biomedical Engineering Department, Saint Louis University Here, a method that enables quick, efficient, and inexpensive preparation of polyacrylamide gels in a multiwell plate format is described. The method does not require any specialized equipment and could be easily adopted by any research laboratory. It would be particularly useful in research focused on understanding stiffness-dependent cell responses. Medicine Murine Corneal Transplantation: A Model to Study the Most Common Form of Solid Organ Transplantation Xiao-Tang Yin1, Deena A. Tajfirouz1, Patrick M. Stuart1 1Department of Ophthalmology, Saint Louis University Mice have been used as a model for studying many forms of transplantation, including corneal transplantation. We describe in this report a murine model for both acute and late-term corneal transplantation. Neuroscience Functional Analysis of the Larval Feeding Circuit in Drosophila Parag K. Bhatt1, Wendi S. Neckameyer1 1Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine The feeding circuit in Drosophila melanogaster larvae serves a simple yet powerful model that allows changes in feeding rate to be correlated with alterations in the stomatogastric neural circuitry. This circuit is composed of central serotonergic neurons that send projections to the mouth hooks as well as the foregut. Engineering Scanning-probe Single-electron Capacitance Spectroscopy Kathleen A. Walsh1, Megan E. Romanowich1, Morewell Gasseller1,2, Irma Kuljanishvili1,3, Raymond Ashoori4, Stuart Tessmer1 1Department of Physics and Astronomy, Michigan State University, 2Department of Chemistry & Biochemistry/Physics, Mercyhurst University, 3Department of Physics, Saint Louis University, 4Department of Physics, Massachusetts Institute of Technology Scanning-probe single-electron capacitance spectroscopy facilitates the study of single-electron motion in localized subsurface regions. A sensitive charge-detection circuit is incorporated into a cryogenic scanning probe microscope to investigate small systems of dopant atoms beneath the surface of semiconductor samples. Medicine An Orthotopic Mouse Model of Anaplastic Thyroid Carcinoma Will Sewell1, Ashley Reeb1, Reigh-Yi Lin1 1Department of Internal Medicine, Division of Endocrinology, Saint Louis University School of Medicine Generation of an orthotopic mouse model of anaplastic thyroid carcinoma is described here. This technique employs surgical placement of human anaplastic thyroid cancer cells into the thyroid of immunodeficient mice, thus creating a more clinically relevant setting to study disease progression as well as screen innovative therapeutic interventions. Immunology and Infection Recurrent Herpetic Stromal Keratitis in Mice, a Model for Studying Human HSK Jessica Morris1, Patrick M. Stuart1, Megan Rogge1, Chloe Potter1, Nipun Gupta1, Xiao-Tang Yin1 1Department of Ophthalmology, Saint Louis University Most studies of herpetic corneal disease use a primary infection model. However, primary infection with HSV-1 does not typically lead to human disease. Here we describe a recurrent model of herpetic corneal disease, which more closely mimics human disease. Biology Isolation and Primary Culture of Rat Hepatic Cells Ling Shen1, Allix Hillebrand2, David Q.-H. Wang3, Min Liu1 1Department of Pathology and Laboratory Medicine, University of Cincinnati College of Medicine, 2American University in Washington, D.C., 3Department of Internal Medicine, Saint Louis University School of Medicine Primary hepatocytes provide a valuable tool to evaluate biochemical, molecular, and metabolic functions in a physiologically relevant experimental system. We describe a reliable protocol for rat in situ liver perfusion, which consistently generates viable hepatocytes up to 1.0 × 108 cells per preparation with cell viability between 88 ~ 96%. Bioengineering Measuring Left Ventricular Pressure in Late Embryonic and Neonatal Mice Victoria P. Le1, Attila Kovacs2, Jessica E. Wagenseil1 1Department of Biomedical Engineering, Saint Louis University, 2Department of Internal Medicine, Washington University School of Medicine Measuring left ventricular pressure (LV) in embryonic and neonatal mice is described. Pressure is measured by inserting a needle connected to a fluid-filled transducer into the LV under ultrasound guidance. Care must be taken to maintain normal cardiac function during the experimental protocol. Bioengineering Mechanical Testing of Mouse Carotid Arteries: from Newborn to Adult Mazyar Amin1, Victoria P. Le1, Jessica E. Wagenseil1 1Department of Biomedical Engineering, Saint Louis University Passive mechanical testing of mouse carotid arteries is described, with special consideration for adapting to different specimen ages. The procedures include determining the in vivo length of the artery, mounting it in a pressure myograph, recording data, measuring the unloaded dimensions and analyzing the resulting data. Biology Determination of DNA Methylation of Imprinted Genes in Arabidopsis Endosperm Matthew Rea1, Ming Chen1, Shan Luan1, Drutdaman Bhangu1, Max Braud1, Wenyan Xiao1 1Department of Biology, Saint Louis University Imprinting is a phenomenon in plant and mammal reproduction. DNA methylation plays an important role in mechanisms of imprinting. Isolating endosperm and determining methylation status of imprinted genes in Arabidopsis can be difficult. In this protocol, we describe how to isolate endosperm and determine methylation by bisulfite sequencing. Biology One-step Metabolomics: Carbohydrates, Organic and Amino Acids Quantified in a Single Procedure James D. Shoemaker1 1Edward A. Doisy Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine The urease method of sample preparation for GC/MS analysis of intermediary metabolites is presented by its inventor. The method allows one-step follow-up of newborn screening for inborn errors by tandem mass spectrometry by quantifying carbohydrates, organic and amino acids all in a single process. Biology Fabrication of Amperometric Electrodes Carolyn M. Pike1, Chad P. Grabner2, Amy B. Harkins1 1Department of Pharmacological and Physiological Science, Saint Louis University School of Medicine, 2Yale University School of Medicine This protocol describes how to generate carbon fiber electrodes. The electrodes are subsequently used to detect catecholamine release from vesicles with carbon fiber amperometry.