JoVE General
Modeling Biological Membranes with Circuit Boards and Measuring Electrical Signals in Axons: Student Laboratory Exercises
1Department of Biology, University of Kentucky, 2Department of Physiology, University of Toronto
This is a demonstration of how biological membranes can be understood using electrical models. We also demonstrate procedures for recording action potentials from the ventral nerve cord of the crayfish for student orientated laboratories.
JoVE Neuroscience
Physiological Experimentation with the Crayfish Hindgut: A Student Laboratory Exercise
1Department of Biology, University of Kentucky, 2Department of Biological Sciences, Brock University
In this report we demonstrate techniques that can be used to investigate the biology of the crayfish hindgut. We show how to dissect a crayfish abdomen and study the associated anatomy, physiology and modulation of activity. The peristaltic activity and strength of contractions are measured using a force transducer.
JoVE Neuroscience
Muscle Receptor Organs in the Crayfish Abdomen: A Student Laboratory Exercise in Proprioception
Department of Biology, University of Kentucky
The primary purpose of this experiment is to understand how primary sensory neurons convey information of joint movements and positions as proprioceptive information for an animal. An additional objective of this report is present the anatomy of the preparation by dissection and viewing of neurons under a dissecting microscope.
JoVE Neuroscience
Membrane Potentials, Synaptic Responses, Neuronal Circuitry, Neuromodulation and Muscle Histology Using the Crayfish: Student Laboratory Exercises
1Department of Biology, University of Kentucky, 2Department of Physiology, University of Toronto
The experiments demonstrate an easy approach for students to gain experience in examining muscle structure, synaptic responses, the effects of ion gradients and permeability on membrane potentials. Also, a sensory-CNS-motor-muscle circuit is presented to show a means to test effects of compounds on a neuronal circuit.
JoVE General
Aseptic Laboratory Techniques: Volume Transfers with Serological Pipettes and Micropipettors
Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles
When working in a laboratory, it is imperative to minimize sources of contamination. Aseptic technique refers to procedures that permit transfer of cultures and reagents while avoiding contact with non-sterile surfaces. Serological pipettes and micropipettors are used to measure precise volumes without compromising sterility of solutions used in experiments.
JoVE General
Microarray Analysis for Saccharomyces cerevisiae
Vermont Genetics Network, The University of Vermont
In this protocol, gene expression in yeast (Saccharomyces cerevisiae) is changed after exposure to oxidative stress induced by the addition of hydrogen peroxide (H2O2), an oxidizing agent.
JoVE Neuroscience
Using a Comparative Species Approach to Investigate the Neurobiology of Paternal Responses
1Department of Psychology, Randolph-Macon College, 2Department of Psychology, Marshall University
The comparative species approach allows behavioral neuroscientists to explore various neurobiological factors associated with specific behaviors viewed as characteristic of a specific animal model. Taking advantage of naturally occurring differences in behavior between closely related species, this technique doesn’t require invasive techniques to manipulate the expression of the behavior.
JoVE Neuroscience
Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making
1Institute for Empirical Research in Economics, Laboratory for Social and Neural Systems Research, University of Zurich, 2Department of Economics, Royal Holloway, University of London
The procedure described in this protocol shows that testosterone administration and folk beliefs about testosterone may be associated with directly opposed social behaviors.
JoVE Neuroscience
Assessing Neurodegenerative Phenotypes in Drosophila Dopaminergic Neurons by Climbing Assays and Whole Brain Immunostaining
Department of Biomolecular Genetics, University of Rochester Medical Center
Here we describe two assays that have been established to study age-dependent neurodegeneration of dopaminergic (DA) neurons in Drosophila: the climbing/startle-induced negative geotaxis assay which allows to study the functional effects of DA neurons degeneration and the tyrosine hydroxylase immunostaining which is used to identify and count DA neurons in whole brain mounts.
JoVE Neuroscience
Rodent Stereotaxic Surgery and Animal Welfare Outcome Improvements for Behavioral Neuroscience
1Department of Neuroscience, Section Anatomy, University Medical Center Groningen, University of Groningen, 2Animal Welfare Office, University of Groningen
Stereotaxic surgery on rodents allows for targeted administration of drugs or electrical stimulation and recordings in awake, behaving animals. In this video presentation we will demonstrate recent procedural refinements to this long-standing procedure that successfully improved survival rate and reduced post-surgical weight loss.
JoVE Clinical and Translational Medicine
Modeling Intracerebral Hemorrhage in Mice: Injection of Autologous Blood or Bacterial Collagenase
1Department of Physiology and Pharmacology, Loma Linda University School of Medicine, 2College of Natural and Agricultural Sciences, University of California, Riverside, 3Department of Anesthesiology, Loma Linda University School of Medicine, 4Department of Neurosurgery, Loma Linda University School of Medicine
Clinically relevant animal models of intracerebral hemorrhage (ICH) are needed to extend our knowledge of hemorrhagic stroke and to examine novel therapeutic strategies. In this study, we describe and evaluate two ICH models that implement unilateral injections of either autologous whole blood or bacterial collagenase into the basal ganglia (corpus striatum) of mice.
JoVE Neuroscience
Human Fear Conditioning Conducted in Full Immersion 3-Dimensional Virtual Reality
1Center for Cognitive Neuroscience, Duke University, 2Pratt School of Engineering, Duke University
Classical fear conditioning paradigm was adapted for human participants in a fully immersive virtual reality setting. Using a discrimination paradigm, conditioned fear, cue and context memory retention, and extinction was measured with skin conductance response to dynamic virtual snakes and spiders (the conditioned stimuli) in two distinct virtual contexts.
JoVE Clinical and Translational Medicine
Functional Assessment of Intestinal Motility and Gut Wall Inflammation in Rodents: Analyses in a Standardized Model of Intestinal Manipulation
Department of Surgery, University of Bonn
Postoperative ileus (POI) is a complication of abdominal surgery leading to increased morbidity and a prolonged hospital stay. Because prophylactic or therapeutic strategies are lacking intensified research is necessary. Therefore we established a standardized and feasible mouse model to investigate the pathophysiology of POI and to study potential therapeutic options.
JoVE Clinical and Translational Medicine
Quantitative Analysis of Cancer Metastasis using an Avian Embryo Model
1Department of Pathology, Vanderbilt University, 2Departments of Oncology, Surgery and Medical Biophysics, London Regional cancer program
Using quantitative PCR, we demonstrate how the well-established chick CAM model can be used to quantitatively analyze the metastasis of human tumor cells to distant organs.
JoVE Neuroscience
Combining Computer Game-Based Behavioural Experiments With High-Density EEG and Infrared Gaze Tracking
1Department of Human Development, Cornell University, 2Social Sciences Division, University of Chicago, 3National Brain Research Centre, Manesar, India
Procedures for recording high-density EEG and gaze data during computer game-based cognitive tasks are described. Using a video game to present cognitive tasks enhances ecological validity without sacrificing experimental control.
JoVE General
An Alternant Method to the Traditional NASA Hindlimb Unloading Model in Mice
1Physical Therapy Department, University of Missouri, Columbia, 2Biomedical Sciences Department, University of Missouri, Columbia
We developed an alternant hindlimb unloading model in mice. The primary advantage of our hindlimb unloading tail-ring method over the conventional Morey-Holton tail-traction technique is a simple straightforward procedure that minimizes stress upon the animal.
JoVE Neuroscience
Rapid Determination of the Thermal Nociceptive Threshold in Diabetic Rats
1Department of Pharmacology and Toxicology, Wright State University, 2Human Movement Laboratory, Universidade São Judas Tadeu
Here, we describe a rapid reliable and simple procedure to determine the lowest temperature at which rats or mice show nocifensive behavior, i.e. the thermal nociceptive threshold (TNT). This method applies a slowly increasing thermal stimulus allowing precise and reproducible estimation of TNTs with minimum, if any, stress to the animals.
JoVE Editorial
The 2009 Lindau Nobel Laureate Meeting: Martin Chalfie, Chemistry 2008
American Biologist Martin Chalfie shared the 2008 Nobel Prize in Chemistry with Roger Tsien and Osamu Shimomura for their discovery and development of the Green Fluorescent Protein (GFP). Chalfie subcloned the coding sequence of GFP and expressed it in both E. coli and C. elegans, demonstrating for the first time that no other factor was required for GFP luminescence.
JoVE General
Recordings of Neural Circuit Activation in Freely Behaving Animals
Department of Psychology, Neuroscience and Cognitive Science Program , University of Maryland
Non-invasive measurements of neural activity patterns in freely behaving animals are obtained by combining neurophysiological recordings with high speed videography.
JoVE General
Using Whole Mount in situ Hybridization to Link Molecular and Organismal Biology
1Department of Biology, Syracuse University, 2Department of Science Teaching, Syracuse University
Whole mount in situ hybridization (WISH) was used in an upper level undergraduate Comparative Vertebrate Biology course in addition to vertebrate dissections. This gave students the opportunity to study gene expression patterns as well as gross anatomy, linking the study of molecular and organismal biology within one course.
JoVE Clinical and Translational Medicine
Using Learning Outcome Measures to assess Doctoral Nursing Education
1Harris College of Nursing and Health Sciences, 2Koehler Center for Teaching Excellence, Texas Christian University
The structure and process for measuring student learning outcomes through customizable assessment rubrics is discussed and applied to a doctoral nursing education program.
JoVE Editorial
December 2011: This Month in JoVE
Here are some highlights from the December 2011 Issue of Journal of Visualized Experiments (JoVE).
JoVE General
Brain Banking: Making the Most of your Research Specimens
1Department of Physiology, University of Montreal, 2School of Optometry, University of Montreal
Brain banking and systematic sampling of biological material provides the basis for unbiased stereology and maximizes the potential data obtained from each specimen.
JoVE General
Trajectory Data Analyses for Pedestrian Space-time Activity Study
1School of Environmental and Life Sciences, Kean University, 2Department of Geography, University of Wisconsin-Madison
A suite of spatiotemporal processing methods are presented to analyze human trajectory data, such as that collected using a GPS device, for the purpose of modeling pedestrian space-time activities.
JoVE Clinical and Translational Medicine
A Simple Method of Mouse Lung Intubation
1Department of Environmental Health Sciences, Program in Respiratory Biology and Lung Disease, Johns Hopkins Bloomberg School of Public Health, 2Department of Pediatrics, Oregon Health Sciences University
This paper describes a striaghforward and efficient method of intubating mice for pulmonary function measurements or pulmonary instillation, that allows the mice to recover and be studied at later times. The procedure involves an inexpensive fiberoptic light source that directly illuminates the trachea.
JoVE General
Aseptic Laboratory Techniques: Plating Methods
Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles
When working with media and reagents used to culture microorganisms, aseptic technique must be practiced to ensure contamination is minimized. A variety of plating methods are routinely used to isolate, propagate, or enumerate bacteria and phage, all of which incorporate procedures that maintain the sterility of experimental materials.
JoVE General
Channelrhodopsin2 Mediated Stimulation of Synaptic Potentials at Drosophila Neuromuscular Junctions
Department of Biology, Brandeis
This procedure uses a blue light-activated algal channel and cell-specific genetic expression tools to evoke synaptic potentials with light pulses at the neuromuscular junction (NMJ) in Drosophila larvae. This technique is an inexpensive and easy-to-use alternative to suction electrode stimulation for synaptic physiology studies in research and teaching laboratories.
JoVE General
Regular Care and Maintenance of a Zebrafish (Danio rerio) Laboratory: An Introduction
1Centre of Excellence for Alzheimer's Disease Research and Care, School of Medical sciences, Edith Cowan University, 2Centre for Clinical Research in Neuropsychiatry, Graylands Hospital, University of Western Australia, 3McCusker Alzheimer's Research foundation, 4School of Medicine and Pharmacology, University of Western Australia, 5Department of Molecular and Biomedical Sciences, University of Adelaide, 6School of Biomedical Sciences, Curtin University of Technology, 7School of Psychiatry and Clinical Neurosciences, University of Western Australia
This protocol outlines regular maintenance and care to maintain optimal conditions for zebrafish husbandry. The video illustrates the protocol for system maintenance, regular housing, feeding, breeding, and raising of zebrafish larvae.
JoVE General
Osmotic Avoidance in Caenorhabditis elegans: Synaptic Function of Two Genes, Orthologues of Human NRXN1 and NLGN1, as Candidates for Autism
1Departamento de Genética, Facultad de Ciencias, Universidad de Córdoba, 2Instituto Maimónides de Investigación Biomédica de Córdoba (IMIBIC)
Neurexins and neuroligins are membrane-neuron adhesion proteins which perform essential roles in synaptic differentiation and transmission. Neuroligin deficient mutants of C. elegans are defective in detecting osmotic strength, but when they also contain a mutation in the gene coding neurexin, they recover the wild type phenotype.
JoVE General
Bacterial Delivery of RNAi Effectors: Transkingdom RNAi
Institute of Pathology, Charité Campus Mitte
For development of RNA interference (RNAi)-based therapies, a novel strategy was developed, transkingdom RNAi (tkRNAi). This technology uses non-pathogenic bacteria to produce and deliver therapeutic short hairpin RNA (shRNA) into target cells. Here, tkRNAi was successfully applied for reversal of classical ABCB1-mediated multidrug resistance (MDR) of cancer cells.
JoVE General
Collection, Isolation and Enrichment of Naturally Occurring Magnetotactic Bacteria from the Environment
1School of Earth Sciences, The Ohio State University, 2School of Environment & Natural Resources, The Ohio State University, 3Institute of Geology and Geophysics, Chinese Academy of Sciences
We demonstrate a method to collect magnetotactic bacteria (MTB) that can be applied to natural waters. MTB can be isolated and enriched from sediment samples using a relatively simple setup that takes advantage of the bacteria's natural magnetism. Isolated MTB can then be examined in detail using both light and electron microscopy.
JoVE Clinical and Translational Medicine
Non-invasive Imaging of Acute Allograft Rejection after Rat Renal Transplantation Using 18F-FDG PET
1Department of Internal Medicine D, Experimental Nephrology, University of Münster, 2Department of Nuclear Medicine, University of Münster, 3European Institute for Molecular Imaging, University of Münster
We herein present a rat renal transplantation model to non-invasively assess acute allograft rejection using positron emission tomography with 18F-fluorodeoxyglucose.
JoVE Clinical and Translational Medicine
A Novel Surgical Approach for Intratracheal Administration of Bioactive Agents in a Fetal Mouse Model
1Molecular Virology and Gene Therapy, KU Leuven, 2Department of Woman and Child, KU Leuven, 3Neurobiology and Gene Therapy, KU Leuven, 4Division of Nuclear Medicine, KU Leuven, 5Biomedical NMR Unit/ MoSAIC, KU Leuven
We developed a novel surgical approach for intratracheal administration of bioactive agents into the mouse fetus. The delivery route is more efficient in targeting the fetal mouse lungs than the commonly used intra-amniotic injection. This procedure has to date not been described in a mouse model.
JoVE General
Microgavage of Zebrafish Larvae
Department of Cell and Molecular Physiology, University of North Carolina at Chapel Hill
We present a novel method for microgavage of larval zebrafish utilizing standard embryo microinjection and stereomicroscopy equipment. We demonstrate that microgavage is a safe and efficient technique useful for delivering controlled amounts of diverse materials specifically into the larval zebrafish intestinal lumen.
JoVE Immunology and Infection
Determination of Molecular Structures of HIV Envelope Glycoproteins using Cryo-Electron Tomography and Automated Sub-tomogram Averaging
1Laboratory of Cell Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, 2The Medical Research Council Mitochondrial Biology Unit, University of Cambridge, 3National Library of Medicine, National Institutes of Health, 4Massachusetts Institute of Technology, 5William Fremd High School, 6University of Virginia, 7Duke University, 8Yale University, 9University of Notre Dame, 10Washington University in St. Louis, 11Bioinformatics and Computational Biosciences Branch, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 12Thomas Jefferson High School for Science and Technology
The protocol describes a high-throughput approach to determining structures of membrane proteins using cryo-electron tomography and 3D image processing. It covers the details of specimen preparation, data collection, data processing and interpretation, and concludes with the production of a representative target for the approach, the HIV-1 Envelope glycoprotein. These computational procedures are designed in a way that enables researchers and students to work remotely and contribute to data processing and structural analysis.
JoVE Neuroscience
Morris Water Maze Test for Learning and Memory Deficits in Alzheimer's Disease Model Mice
Department of Psychiatry, Brain Research Center, University of British Columbia
The Morris Water Maze is a behavioral task to test hippocampal-dependent learning and memory. It has been widely used in the study of neurobiology, neuropharmacology and neurocognitive disorders in rodent models.
JoVE Immunology and Infection
Assessing Somatic Hypermutation in Ramos B Cells after Overexpression or Knockdown of Specific Genes
Department of Immunology, Duke University
We describe how to perform retroviral or lentiviral infections of overexpression or shRNA-containing constructs in the human Ramos B-cell line and how to measure somatic hypermutation in these cells.
JoVE Clinical and Translational Medicine
Femoral Arterial and Venous Catheterization for Blood Sampling, Drug Administration and Conscious Blood Pressure and Heart Rate Measurements
Department of Pharmacology and Toxicology, Michigan State University
Chronic catheterization of blood vessels in the rat is often required for administration of substances, obtain blood sample over a period of time or for direct conscious blood pressure measurements. Femoral arterial catheterization of the rat and corresponding measurements of blood pressure in the conscious animal will be demonstrated.
JoVE Immunology and Infection
Staphylococcus aureus Growth using Human Hemoglobin as an Iron Source
Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical School
Here we describe a growth assay for Staphylococcus aureus using hemoglobin as the sole source of available nutrient iron. This assay establishes the role of bacterial factors involved in hemoglobin-derived iron acquisition.
JoVE Clinical and Translational Medicine
In vitro Organoid Culture of Primary Mouse Colon Tumors
1Department of Molecular & Integrative Physiology, University of Michigan, 2Department of Internal Medicine, Division of Gastroenterology, University of Michigan
A simple method to establish primary murine colon tumor organoid is described. This method utilizes the feature that colon tumor cells survive and grow into organoids in media containing limited growth factors, whereas normal colon epithelial do not.
JoVE Immunology and Infection
Assessing Stomatal Response to Live Bacterial Cells using Whole Leaf Imaging
Biology, University of Texas at Arlington
We have developed a simple and reproducible protocol to access stomatal response to live bacteria. This method minimizes wounding and manipulation of the leaf as compared to the use of epidermal peels reported previously.
JoVE Bioengineering
A Simple Hanging Drop Cell Culture Protocol for Generation of 3D Spheroids
Department of Surgery, UMDNJ-Robert Wood Johnson Medical School
We describe a simple, rapid method of generating 3D tissue-like spheroids and their potential application to quantify differences in cell-cell interactions.
JoVE General
Agarose Gel Electrophoresis for the Separation of DNA Fragments
Department of Molecular, Cell, and Developmental Biology, University of California Los Angeles
A basic protocol for the separation of DNA fragments using agarose gel electrophoresis is described.
JoVE Neuroscience
The Dig Task: A Simple Scent Discrimination Reveals Deficits Following Frontal Brain Damage
Department of Psychology, Southern Illinois University at Carbondale
In this protocol, a novel application of scent discrimination is described. The Dig task is a reasonably inexpensive task that can be used to assess frontally-mediated cognition following brain damage.
JoVE Bioengineering
Quantitative Locomotion Study of Freely Swimming Micro-organisms Using Laser Diffraction
1Physics & Astronomy Department, Vassar College, 2Biology Department, Vassar College
Microscopic organisms like the free-swimming nematode C. elegans, live and behave in a complex three-dimensional environment. We report on a novel approach that provides analysis of C. elegans using diffraction patterns. This approach consists of tracking the temporal periodicity of diffraction patterns generated by directing laser light through a cuvette.
JoVE General
Principles of Rodent Surgery for the New Surgeon
Charles River, Research Models and Services
Before attempting surgery, a new surgeon should have training in basic surgical techniques and concepts. This article will present basic surgical considerations with an emphasis on rodents.
JoVE Application Notes
Pre-Roll Demo (Standard) - ADVERTISEMENT
For both scientific and animal welfare reasons, training in basic surgical concepts and techniques should be undertaken before ever seeking to perform surgery on a rodent. Students, post-doctoral scholars, and others interested in performing surgery on rodents as part of a research protocol may not have had formal surgical training as part of their required coursework. Surgery itself is a technical skill, and one that will improve with practice. The principles of aseptic technique, however, often remain unexplained or untaught. For most new surgeons, this vital information is presented in piecemeal fashion or learned on the job, neither of which is ideal. It may also make learning how to perform a particular surgery difficult, as the new surgeon is learning both a surgical technique and the principles of asepsis at the same time. This article summarizes and makes recommendations for basic surgical skills and techniques necessary for successful rodent surgery. This article is designed to supplement hands-on training by the user's institution.
JoVE Application Notes
Pre-Roll Demo (Premium) - ADVERTISEMENT
For both scientific and animal welfare reasons, training in basic surgical concepts and techniques should be undertaken before ever seeking to perform surgery on a rodent. Students, post-doctoral scholars, and others interested in performing surgery on rodents as part of a research protocol may not have had formal surgical training as part of their required coursework. Surgery itself is a technical skill, and one that will improve with practice. The principles of aseptic technique, however, often remain unexplained or untaught. For most new surgeons, this vital information is presented in piecemeal fashion or learned on the job, neither of which is ideal. It may also make learning how to perform a particular surgery difficult, as the new surgeon is learning both a surgical technique and the principles of asepsis at the same time. This article summarizes and makes recommendations for basic surgical skills and techniques necessary for successful rodent surgery. This article is designed to supplement hands-on training by the user's institution.
JoVE Immunology and Infection
Examining the Role of Nasopharyngeal-associated Lymphoreticular Tissue (NALT) in Mouse Responses to Vaccines
U.S. Army Medical Research Institute of Infectious Diseases
Methods to examine contributions of the nasopharyngeal-associated lymphoreticular tissues (NALT) to nasal and systemic immune responses of mice to intranasal vaccines are described. We demonstrate a surgical procedure to establish a NALT-dependent mouse model and ex vivo cultures of extracted NALT.
JoVE General
Mapping the After-effects of Theta Burst Stimulation on the Human Auditory Cortex with Functional Imaging
Auditory processing is the basis of speech and music-related processing. Transcranial Magnetic Stimulation (TMS) has been used successfully to study cognitive, sensory and motor systems but has rarely been applied to audition. Here we investigated TMS combined with functional Magnetic Resonance Imaging to understand the functional organization of auditory cortex.
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