Vertical T-maze Choice Assay for Arthropod Response to Odorants
Entomology and Nematology Department, University of Florida
A vertical, T-maze olfactometer is described for assaying the behavioral response of arthropods. The olfactometer allows the experimenter to measure choices performed by test subjects when subjected to two potential odor fields. Both attraction to and repulsion from odorants can be measured with this device.
Electroantennographic Bioassay as a Screening Tool for Host Plant Volatiles
Plant Mycotoxin Research, U.S. Department of Agriculture, Agricultural Research Service
A method to rapidly screen host plant volatiles by measurement of the electrophysiological response of adult navel orangeworm (Amyelois transitella) antennae to single components and blends via electroantennographic analysis is demonstrated.
Protocols for Microapplicator-assisted Infection of Lepidopteran Larvae with Baculovirus
Department of Entomology, Iowa State University
In this video, we demonstrate two microapplicator techniques used to infect of lepidopteran larvae with baculovirus in order to determine insecticidal efficiency.
Protocols for Oral Infection of Lepidopteran Larvae with Baculovirus
Department of Entomology, Iowa State University
In this video, we demonstrate oral infection techniques of lepidopteran larvae with baculovirus in order to determine insecticidal efficiency.
A Calcium Bioluminescence Assay for Functional Analysis of Mosquito (Aedes aegypti) and Tick (Rhipicephalus microplus) G Protein-coupled Receptors
1Department of Entomology, Texas A&M University (TAMU), 2Department of Molecular and Cellular Medicine, Texas A&M University (TAMU)
This protocol provides instructions for clonal-cell line selection and a calcium bioluminescence assay to analyze the structure-activity relationships of synthesized arthropod neuropeptides on their cognate GPCRs. This assay can be used for receptor deorphanization and structure-activity relationship studies for synthetic analog design and peptide/drug-lead discovery.
Establishing Fungal Entomopathogens as Endophytes: Towards Endophytic Biological Control
1Entomology, International Center for Tropical Agriculture (CIAT), Cali, Colombia, 2Sustainable Perennial Crops Laboratory, Agricultural Research Service, United States Department of Agriculture, Beltsville, Maryland, USA
This protocol demonstrates two inoculation methods to introduce the fungal entomopathogen Beauveria bassiana as an endophyte in the common bean (Phaseolus vulgaris), in preparation for subsequent evaluations of endophytic biological control.
Electrophysiological Measurements from a Moth Olfactory System
Department of Entomology, University of California, Davis
Insect olfactory systems provide unique opportunities for recording odorant-induced responses in the forms of electroantennograms (EAG) and single sensillum recordings (SSR), which are summed responses from all odorant receptor neurons (ORNs) located on the antenna and from those housed in individual sensilla, respectively.
Bioassays for Monitoring Insecticide Resistance
1Division of Plant Sciences, University of Missouri, Delta Research Center, 2Department of Entomology, Louisiana State University Agricultural Center
This manuscript demonstrates and discusses techniques used to survey pesticide susceptibility and detect resistance to contact and systemic pesticides in arthropod pests.
Characterizing Herbivore Resistance Mechanisms: Spittlebugs on Brachiaria spp. as an Example
International Center for Tropical Agriculture, CIAT
This video explains mechanisms of host plant resistance to herbivory and demonstrates a no-choice test that estimates the relative contributions of antibiosis and tolerance to spittlebug resistance in Brachiaria spp.
Single Sensillum Recordings in the Insects Drosophila melanogaster and Anopheles gambiae
Laboratory of Neurogenetics and Behavior, Rockefeller University
Electrophysiological responses of olfactory sensory neurons to odorants can be measured in insects using single sensillum recordings. In this video article we will demonstrate how to perform single sensillum recordings in the antennae of the vinegar fly (Drosophila melanogaster) and the maxillary palps of the malaria mosquito (Anopheles gambiae).
Rearing and Injection of Manduca sexta Larvae to Assess Bacterial Virulence
Department of Bacteriology, University of Wisconsin-Madison
The method described here utilizes direct injection of entomopathogenic bacteria into the hemocoel of Manduca sexta insect larvae. M. sexta is a commercially available and well-studied insect. Thus, this method represents a simple approach to analyzing host-bacterial interactions from the perspective of one or both partners.
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Product Management, Sigma-Aldrich
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Choice and No-Choice Assays for Testing the Resistance of A. thaliana to Chewing Insects
Boyce Thompson Institute for Plant Research, Cornell University
Plant resistance to chewing insect herbivores can be tested in several ways. Here, we demonstrate how to set-up a choice and a no-choice experiment with the model plant Arabidopsis thaliana to identify resistance against the pest species Pieris rapae.
A Simple Protocol for Extracting Hemocytes from Wild Caterpillars
Department of Biological Sciences, The George Washington University
Insect hemocytes carry out many important functions, both immune and non-immune, throughout all stages of insect development. Our present knowledge of hemocyte types and function comes from studies on insect genetic models. Here, we present a method for extracting, quantifying and visualizing hemocytes from wild caterpillars.
In ovo Electroporation of miRNA-based Plasmids in the Developing Neural Tube and Assessment of Phenotypes by DiI Injection in Open-book Preparations
Institute of Molecular Life Sciences, University of Zurich
A method by which gene expression in the neural tube can be downregulated in a cell type-specific, traceable manner is described. We demonstrate how in ovo electroporation of microRNA-based plasmids that elicit spatiotemporally controlled RNA interference can be used to investigate commissural axon guidance in the developing neural tube.
Identification of Olfactory Volatiles using Gas Chromatography-Multi-unit Recordings (GCMR) in the Insect Antennal Lobe
Department of Biology, University of Washington
Olfactory cues mediate many different behaviors in insects, and are often complex mixtures comprised of tens to hundreds of volatile compounds. Using gas chromatography with multi-channel recording in the insect antennal lobe, we describe a method for the identification of bioactive compounds.
The Insect Galleria mellonella as a Powerful Infection Model to Investigate Bacterial Pathogenesis
Oral and intra haemocolic infection of larvae of the greater wax moth Galleria mellonella is described. This insect can be used to study virulence factors of entomopathogenic as well as mammalian opportunistic bacteria. Rearing of the insects, methods of infection and examples of in vivo analysis are described.
An Optimized Protocol for Rearing Fopius arisanus, a Parasitoid of Tephritid Fruit Flies
Fopius arisanus is an egg-larval parasitoid of Tephritid fruit flies that is successfully used in biological control of these important tropical pests. We describe here an optimized protocol for rearing F. arisanus on a small scale using readily available materials.
A Protocol for Collecting and Staining Hemocytes from the Yellow Fever Mosquito Aedes aegypti
Department of Biology, University of Richmond
A simplified yet accurate method to collect and stain mosquito hemocytes is described. Our method combines the simplicity of perfusion with the accuracy of high injection techniques to isolate clean preparations of hemocytes in Aedes mosquitoes. This method facilitates studies requiring knowledge of the types of hemocytes and their abundance.
Breathing-controlled Electrical Stimulation (BreEStim) for Management of Neuropathic Pain and Spasticity
1Department of Physical Medicine and Rehabilitation, University of Texas Health Science Center at Houston, 2UTHealth Motor Recovery Laboratory, TIRR Memorial Hermann Hospital, 3The Institute of Rehabilitation and Research (TIRR), TIRR Memorial Hermann Hospital
The purpose is to present a new method, breathing-control electrical stimulation (BreEStim) for management of neuropathic pain and spasticity.
High-throughput Physical Mapping of Chromosomes using Automated in situ Hybridization
Department of Entomology, Virginia Tech
Genome assemblies based on massively parallel DNA sequencing technologies are usually highly fragmented. The development of physical chromosome maps can potentially improve genome assemblies. Here, we demonstrate innovative approaches to chromosome preparation, fluorescent in situ hybridization, and imaging that significantly increase throughput of the physical map development.
Using Visual and Narrative Methods to Achieve Fair Process in Clinical Care
1Institute for Behavioral Health, Brandeis University, 2Heller School for Social Policy and Management, Brandeis University
This paper illustrates an innovative visual approach (photovoice or photo-elicitation) to achieve fair process in clinical care for patients living with chronic health conditions, illuminate gaps in clinical knowledge, forge better therapeutic relationships, and identify patient-centered goals and possibilities for healing.
Optimized PCR-based Detection of Mycoplasma
Product Management, Sigma-Aldrich
The LookOut Mycoplasma PCR Detection Kit utilizes the polymerase chain reaction (PCR), which is established as the method of choice for highest sensitivity in the detection of Mycoplasma, Acholeplasma, and Ureaplasma contamination in cell cultures and other cell culture derived biologicals.
Loading Drosophila Nerve Terminals with Calcium Indicators
Department of Physiology, University of Texas Health Science Center at San Antonio (UTHSCSA)
Calcium is a ubiquitous messenger in the nervous system, essential for triggering neurotransmitter release and changes in synaptic strength. Here we demonstrate a technique for loading Ca2+-indicators into Drosophila nerve terminals. We also demonstrate fabrication of the required apparatus and emphasize points critical for the technique's success.
Fluorescent in situ Hybridization on Mitotic Chromosomes of Mosquitoes
Department of Entomology, Virginia Tech
Among the three mosquito genera, namely Anopheles, Aedes, and Culex, physical genome mapping techniques were established only for Anopheles, whose members possess readable polytene chromosomes. For the genera of Aedes and Culex, however, cytogenetic mapping remains challenging because of the poor quality of polytene chromosomes. Here we present a universal protocol for obtaining high-quality preparations of mitotic chromosomes and an optimized FISH protocol for all three genera of mosquitoes.
Analysis of Gene Expression in Emerald Ash Borer (Agrilus planipennis) Using Quantitative Real Time-PCR
Department of Entomology, The Ohio State University
Quantitative real-time PCR (qRT-PCR) is an effective tool to diagnose mRNA levels in different insect tissues and developmental stages. In this report we show the use of qRT-PCR to ascertain mRNA levels in different larval tissues and developmental stages of the invasive insect species, emerald ash borer.
Preparation of Drosophila S2 cells for Light Microscopy
Department of Cell Biology and Anatomy, University of Arizona (UOA)
Drosophila Schneider (S2) cells are an increasingly popular system for the discovery and functional analysis of genes. Our goal is to describe some of the microscopic techniques that make S2 cells such an increasingly important experimental system.
Microdissection of Black Widow Spider Silk-producing Glands
Department of Biological Sciences, University of the Pacific
Here we describe an efficient strategy to remove the silk-producing glands from the abdomen of female black widow spiders. This procedure allows the rapid isolation of the seven distinct silk-producing glands in a highly purified fashion, an important process for investigators studying spider silk production and fiber assembly.
Testing Protozoacidal Activity of Ligand-lytic Peptides Against Termite Gut Protozoa in vitro (Protozoa Culture) and in vivo (Microinjection into Termite Hindgut)
Department of Entomology, Louisiana State University Agricultural Center
We present procedures for demonstrating that ligands bind to the surface membrane of the cellulose-digesting protozoa in the gut of Formosan subterranean termites using fluorescent microscopy and that ligands coupled with lytic peptides kill these protozoa in vitro (anaerobic protozoa culture) and in vivo (injection into the termite hindgut).
Live Imaging of Glial Cell Migration in the Drosophila Eye Imaginal Disc
Department of Zoology, University of British Columbia - UBC
Here we describe a protocol to examine the migration of glial cells into the developing Drosophila eye using live microscopic analysis paired with GFP tagged glial cells.
Single Cell Transfection in Chick Embryos
Department of Medical Neurobiology, Hadassah Medical School - Hebrew University
Using fine tip micropipettes we inject plasmid DNA into subdomains of chicken somites or neural tubes. The concentration of the plasmid is adjusted to generate single transfected cells. We then allow the cells to develop into clonal populations.
Dissection of Oenocytes from Adult Drosophila melanogaster
Department of Biology, University of Toronto
In insects, the oenocytes produce cuticular hydrocarbon compounds. These compounds protect against desiccation and facilitate chemical communication. Here we demonstrate a dissection technique used to isolate the oenocytes from adult Drosophila melanogaster, and illustrate how this preparation can be utilized to study genes involved in hydrocarbon synthesis.
Morphological Analysis of Drosophila Larval Peripheral Sensory Neuron Dendrites and Axons Using Genetic Mosaics
1Disease Mechanism Research Core, RIKEN Brain Science Institute, 2Graduate School of Science and Engineering, Saitama University
The dendritic arborization sensory neurons of the Drosophila larval peripheral nervous system are useful models to elucidate both general and neuron class-specific mechanisms of neuron differentiation. We present a practical guide to generate and analyze dendritic arborization neuron genetic mosaics.
Creating Rigidly Stabilized Fractures for Assessing Intramembranous Ossification, Distraction Osteogenesis, or Healing of Critical Sized Defects
Department of Orthopaedic Surgery, University of California, San Francisco
This article describes a method for stabilizing long bone fractures that is based on the application of modified Ilizarov external fixators 1-3. After application of the fixators and creation of the bone injury, healing can be assessed, distraction osteogenesis can be performed, or non-union or critical sized defect can be created and used to study therapeutic interventions.
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.
Analyzing Murine Schwann Cell Development Along Growing Axons
1Department of Molecular Embryology, Institute of Anatomy and Cell Biology, University of Freiburg, 2Department of Neuroanatomy, University of Heidelberg, 3FRIAS, University of Freiburg
Here we describe a Schwann cell (SC) migration assay in which SCs are able to develop along extending axons.
Microsurgical Venous Pouch Arterial-Bifurcation Aneurysms in the Rabbit Model: Technical Aspects
1Department of Neurosurgery, Hospital Rudolfstiftung, 2Department of Neurosurgery, Kantonsspital Aarau, 3Cerebrovascular Research Group, Department of Biomedical Research, Medical University of Vienna, 4Cerebrovascular Research Group, Department of Intensive Care Medicine, University of Berne, 5Centre for Anatomy and Cell Biology, Department of Systematic Anatomy, Medical University of Vienna, 6Department of Neurology, Paracelsus University Salzburg
An optimized technique for the microsurgical creation of arterial bifurcation aneurysms mimicking bifurcation human cerebral aneurysms is described. A venous pouch is sutured into an artificially created true bifurcation of both common carotid arteries. Facilitated microsurgical techniques and aggressive postoperative anticoagulation and analgesia lead to minimized morbidity rates and high aneurysm patency rates.
Guidelines for Elective Pediatric Fiberoptic Intubation
1Department of Anesthesia, St. Jude Children's Research Hospital, 2Department of Anesthesia, Children's Hospital of Michigan, 3Department of Anesthesiology, Children's Hospital of Michigan
We describe guidelines to perform a safe and efficient elective fiberoptic intubation in pediatric patients while maintaining spontaneous ventilation.
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Pharmaceutical Business Operations, Waters Corporation
RNAi-mediated Gene Knockdown and In Vivo Diuresis Assay in Adult Female Aedes aegypti Mosquitoes
1Biology Department, New Mexico State University, 2Molecular Biology Department, New Mexico State University
In this protocol we combine RNAi-mediated gene silencing with an in vivo diuresis assay to study the effects knockdown of genes of interest has on mosquito fluid excretion.
Spatial Multiobjective Optimization of Agricultural Conservation Practices using a SWAT Model and an Evolutionary Algorithm
1School of Environmental and Forest Sciences, University of Washington, 2Center for Agricultural and Rural Development, Department of Economics, Iowa State University, 3Department of Civil, Architectural, and Environmental Engineering, North Carolina A&T University, 4Iowa Geological and Water Survey
This work demonstrates an integration of a water quality model with an optimization component utilizing evolutionary algorithms to solve for optimal (lowest-cost) placement of agricultural conservation practices for a specified set of water quality improvement objectives. The solutions are generated using a multi-objective approach, allowing for explicit quantification of tradeoffs.
A Novel Rescue Technique for Difficult Intubation and Difficult Ventilation
1Department of Anesthesia, Children’s Hospital of Michigan, 2Department of Anesthesia, St. Jude Children’s Research Hospital
We describe a technique to maintain oxygenation and ventilation using an endotracheal tube inserted nasally to the level of the naso-pharynx while sealing the mouth and nares for successful positive pressure ventilation.
July 2011: This Month in JoVE
Here are some highlights from the July 2011 Issue of Journal of Visualized Experiments (JoVE).
Surgical Management of Meatal Stenosis with Meatoplasty
Department of Urology, Pediatric Urology, Johns Hopkins School of Medicine
Meatoplasty, surgical management of meatal stenosis.
In vivo Ca2+- Imaging of Mushroom Body Neurons During Olfactory Learning in the Honey Bee
1Institut für Biologie - Neurobiologie, Freie Universität Berlin, 2Institut für Biologie - Neurobiologie, Free University Berlin - Freie Universitaet Berlin
Bees can be conditioned in an appetitive olfactory learning paradigm (PER-conditioning). Using odors as stimuli, we established a method in which behavior is recorded while simultaneously Calcium Imaging is used to measure odor evoked activity in mushroom body neurons in vivo.
Improving IV Insulin Administration in a Community Hospital
When compared to the previous paper protocol, implementation of a computerized glucose management system results in a substantial increase in blood glucose concentration measurements within the target range. Using a computerized glucose management system to monitor blood glucose levels, decreases in severe hypoglycemia (<40 mg/dL), clinical hypoglycemia (<70 mg/dL), and hyperglycemia (>180 mg/dL) also can be observed.
Primary Neuronal Cultures from the Brains of Late Stage Drosophila Pupae
This video demonstrates the preparation of primary neuronal cultures from the brains of late stage Drosophila pupae. Views of live cultures show neurite outgrowth and imaging of calcium levels using Fura-2.
Alphavirus Transducing System: Tools for Visualizing Infection in Mosquito Vectors
Microbiology, Immunology, and Pathology, Colorado State University
Methods for using alphavirus transducing systems to express fluorescent reporters in vitro and in adult mosquitoes are described. This technique may be adapted to express any protein of interest in lieu of or in addition to a reporter.
Hybridization in situ of Salivary Glands, Ovaries, and Embryos of Vector Mosquitoes
1Department of Molecular Biology and Biochemistry, University of California, Irvine, 2Department of Microbiology and Molecular Genetics, University of California, Irvine
Temporal and spatial gene expression analyses have a crucial role in functional genomics. Whole-mount hybridization in situ is useful for determining the localization of transcripts within tissues and subcellular compartments. Here we outline a hybridization in situ protocol with modifications for specific target tissues in mosquitoes.
Measurement of Lifespan in Drosophila melanogaster
1Department of Molecular and Integrative Physiology, University of Michigan, 2Cellular and Molecular Biology Program, University of Michigan
Drosophila melanogaster is a powerful model organism for exploring the molecular basis of longevity regulation. This protocol will discuss the steps involved in generating a reproducible, population-based measurement of longevity as well as potential pitfalls and how to avoid them.
