Kennedy Krieger Institute 4 articles published in JoVE Developmental Biology Performing Human Skeletal Muscle Xenografts in Immunodeficient Mice Kyla A. Britson1,2, Aaron D. Black2,3, Kathryn R. Wagner1,2,3,4, Thomas E. Lloyd1,2,4 1Graduate Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, 2Department of Neurology, Johns Hopkins University School of Medicine, 3Kennedy Krieger Institute, 4Department of Neuroscience, Johns Hopkins University School of Medicine Complex human diseases can be challenging to model in traditional laboratory model systems. Here, we describe a surgical approach to model human muscle disease through the transplantation of human skeletal muscle biopsies into immunodeficient mice. Medicine Whole-brain Segmentation and Change-point Analysis of Anatomical Brain MRI—Application in Premanifest Huntington's Disease Dan Wu1, Andreia V. Faria1, Laurent Younes2,3,4, Christopher A. Ross5, Susumu Mori1,6, Michael I. Miller2,3,7 1The Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 2Center for Imaging Science, Johns Hopkins University, 3Institute for Computational Medicine, Johns Hopkins University, 4Department of Applied Mathematics and Statistics, Johns Hopkins University, 5Division of Neurobiology, Departments of Psychiatry, Neurology, Neuroscience and Pharmacology, and Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, 6F.M. Kirby Research Center for Functional Brain Imaging, Kennedy Krieger Institute, 7Department of Biomedical Engineering, Johns Hopkins University This paper describes a statistical model for volumetric MRI data analysis, which identifies the "change-point" when brain atrophy begins in premanifest Huntington's disease. Whole-brain mapping of the change-points is achieved based on brain volumes obtained using an atlas-based segmentation pipeline of T1-weighted images. Neuroscience Online Transcranial Magnetic Stimulation Protocol for Measuring Cortical Physiology Associated with Response Inhibition Michael D. Guthrie1, Donald L. Gilbert2, David A. Huddleston2, Ernest V. Pedapati2,3, Paul S. Horn2, Stewart H. Mostofsky4, Steve W. Wu2 1College of Medicine, University of Cincinnati, 2 We describe an experimental procedure to quantify excitability and inhibition of primary motor cortex during a motor response inhibition task by using Transcranial Magnetic Stimulation throughout the course of a Stop Signal Task. Medicine Adapted Resistance Training Improves Strength in Eight Weeks in Individuals with Multiple Sclerosis Jennifer L. Keller1, Nora Fritz1,2, Chen Chun Chiang1, Allen Jiang1, Tziporah Thompson3, Nicole Cornet1, Scott D. Newsome4, Peter A. Calabresi4, Kathleen Zackowski1,2,4 1Motion Analysis Laboratory, Kennedy Krieger Institute, 2Physical Medicine & Rehabilitation, Johns Hopkins University School of Medicine, 3Johns Hopkins University School of Medicine, 4Department of Neurology, Johns Hopkins University School of Medicine Hip weakness is a common symptom affecting walking ability in people with multiple sclerosis. Isolated muscle strengthening is a useful method to target specific weaknesses. This protocol describes a progressive resistance-training program using exercise bands to increase hip muscle strength.