Drexel University College of Medicine 7 articles published in JoVE Bioengineering Investigating Stress-relaxation and Failure Responses in the Trachea Anita Singh1, Tanmay Majmudar2,3, Adi Iyer4, Diya Iyer4, Sriram Balasubramanian3 1Department of Biomedical Engineering, Widener University, 2Drexel University College of Medicine, 3School of Biomedical Engineering, Science and Health Systems, Drexel University, 4Rosetree Media School District The present protocol determines the tensile stress-relaxation and failure properties of porcine tracheae. Results from such methods can help improve the understanding of the viscoelastic and failure thresholds of the trachea and help advance the capabilities of computational models of the pulmonary system. Cancer Research An Ex Vivo Brain Slice Model to Study and Target Breast Cancer Brain Metastatic Tumor Growth Lorela Ciraku1, Rebecca A. Moeller1, Emily M. Esquea1, Wiktoria A. Gocal1, Edward J. Hartsough2,4, Nicole L. Simone3,4, Joshua G. Jackson2, Mauricio J. Reginato1,4 1Department of Biochemistry and Molecular Biology, Drexel University College of Medicine, 2Department of Pharmacology and Physiology, Drexel University College of Medicine, 3Department of Radiation Oncology, Thomas Jefferson University, 4Sidney Kimmel Cancer Center, Thomas Jefferson University We introduce a protocol for measuring real-time drug and radiation response of breast cancer brain metastatic cells in an organotypic brain slice model. The methods provide a quantitative assay to investigate the therapeutic effects of various treatments on brain metastases from breast cancer in an ex vivo manner within the brain microenvironment interface. Neuroscience Uptake of Fluorescent Labeled Small Extracellular Vesicles In Vitro and in Spinal Cord Richa Gupta1, Xuan Luo1, Zhucheng Lin1, Yuzhen Tian1, Seena K. Ajit1 1Department of Pharmacology & Physiology, Drexel University College of Medicine We describe a protocol to label macrophage-derived small extracellular vesicles with PKH dyes and observe their uptake in vitro and in the spinal cord after intrathecal delivery. Genetics Combining Laser Capture Microdissection and Microfluidic qPCR to Analyze Transcriptional Profiles of Single Cells: A Systems Biology Approach to Opioid Dependence Sean J. O'Sullivan1,2, Beverly A.S. Reyes3, Rajanikanth Vadigepalli1, Elisabeth J. Van Bockstaele3, James S. Schwaber1 1Daniel Baugh Institute for Functional Genomics and Computational Biology, Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University, 2Sidney Kimmel Medical College, Thomas Jefferson University, 3Department of Pharmacology & Physiology, Drexel University College of Medicine This protocol explains how to collect single neurons, microglia, and astrocytes from the central nucleus of the amygdala with high accuracy and anatomic specificity using laser capture microdissection. Additionally, we explain our use of microfluidic RT-qPCR to measure a subset of the transcriptome of these cells. Biochemistry Identification of Novel CK2 Kinase Substrates Using a Versatile Biochemical Approach John E. Chojnowski1, Emily A. McMillan1, Todd I. Strochlic1 1Department of Biochemistry and Molecular Biology, Drexel University College of Medicine The objective of this protocol is to label, enrich, and identify substrates of protein kinase CK2 from a complex biological sample such as a cell lysate or tissue homogenate. This method leverages unique aspects of CK2 biology for this purpose. Biology Preparation of Meiotic Chromosome Spreads from Mouse Spermatocytes Ferdusy Dia1, Tierra Strange1, Jenny Liang1, Jacob Hamilton1, Karen M. Berkowitz1,2 1Department of Biochemistry & Molecular Biology, Drexel University College of Medicine, 2Department of Obstetrics & Gynecology, Drexel University College of Medicine Meiosis is the developmental process by which gametes are formed through a single round of DNA replication and two successive rounds of chromosome segregation. Mammalian meiosis can be examined by utilizing a technique to prepare meiotic chromosome spreads. Here, we demonstrate a method of preparing surface-spread nuclei from mouse spermatocytes. Medicine A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts Shaoping Hou1, Armin Blesch2, Paul Lu3,4 1Spinal Cord Research Center, Department of Neurobiology & Anatomy, Drexel University College of Medicine, 2Spinal Cord Injury Center, Heidelberg University Hospital, 3Veterans Administration Medical Center, San Diego, CA, 4Department of Neurosciences, University of California, San Diego We present a protocol for using a radio-telemetric system to record cardiovascular parameters in T4 spinal cord transected rats eight weeks after embryonic brainstem neural stem cell grafting into the lesion site. Telemetry is an advanced technique to accurately evaluate cardiovascular function in conscious freely moving spinal cord injured rats.