JoVE Clinical and Translational Medicine
A New Single Chamber Implantable Defibrillator with Atrial Sensing: A Practical Demonstration of Sensing and Ease of Implantation
Heart Center Rostock, University Hospital of Rostock, Germany
Dual-chamber implantable cardioverter-defibrillators (ICDs) may improve detection of atrial fibrillation as well as differentiation of tachycardias. However, this advantage is undermined by complications associated with the second electrode, which is required in conventional dual chamber devices. Therefore, BIOTRONIK has developed a new electrode called the LinoxSMART S DX that, when used in conjunction with the Lumax DX ICD, offers dual-chamber detection without the risks associated with the second electrode.
JoVE Clinical and Translational Medicine
Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
Department of Pharmacology and Toxicology, University of Utah
Techniques for measurement of electrical activity of the heart by electrocardiogram (ECG), and analysis of cardiac risk factors and susceptibility to arrhythmias following status epilepticus (SE) in the rat are described.
JoVE Clinical and Translational Medicine
Tilt Testing with Combined Lower Body Negative Pressure: a "Gold Standard" for Measuring Orthostatic Tolerance
Department of Biomedical Physiology and Kinesiology, Simon Fraser University
We describe a "gold standard" for evaluating orthostatic tolerance (OT) using tilt testing with combined lower body negative pressure (LBNP). This can be combined with non-invasive evaluations of cardiovascular reflex control. Normal and abnormal responses are defined.
JoVE General
Conversion of a Capture ELISA to a Luminex xMAP Assay using a Multiplex Antibody Screening Method
1Chemistry Research and Development, Luminex Corporation, 2Global Marketing, Luminex Corporation
An ELISA can be easily converted to a Luminex xMAP assay and, through the benefits of multiplexing, several antibodies can be screened simultaneously to identify an optimum antibody pair, resulting in increased sensitivity and dynamic range, while reducing assay cost.
JoVE General
Ambulatory ECG Recording in Mice
1Department of Molecular Physiology and Biophysics, Baylor College of Medicine (BCM), 2The Margaret M. and Albert B. Alkek Department of Medicine, Baylor College of Medicine (BCM)
Telemetric ECG has emerged as an essential tool in evaluating animal models for cardiac arrhythmias and sudden cardiac death. Here, we present a stepwise guide to telemetric ECG recordings for application in long-term ambulatory ECG monitoring in mice.
JoVE General
Use of the Protease Fluorescent Detection Kit to Determine Protease Activity
The Protease Fluorescent Detection Kit is designed for the measurement of protease activity using fluorometry. It is also suitable for detection of trace amounts of protease contamination. The method is based on the proteolytic hydroysis of a proprietary formulation of a FITC-labeled casein substrate.
JoVE General
Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
1Department of Medicine, Albert Einstein College of Medicine, 2Diabetes Research and Training Center, Albert Einstein College of Medicine, 3Department of Genetics, Albert Einstein College of Medicine
An accurate, short, sophisticated and cheap method is described that assesses telomere length in multiple tissues and species using qRT-PCR. In addition, we will describe a simple assay to assess telomerase activity as a complementary backbone test for telomere length.
JoVE Bioengineering
Patient-specific Modeling of the Heart: Estimation of Ventricular Fiber Orientations
A methodology to estimate ventricular fiber orientations from in vivo images of patient heart geometries for personalized modeling is described. Validation of the methodology performed using normal and failing canine hearts demonstrate that that there are no significant differences between estimated and acquired fiber orientations at a clinically observable level.
JoVE General
Sigma's Non-specific Protease Activity Assay - Casein as a Substrate
Proteases break peptide bonds. In the lab, it is often necessary to measure and/or compare the activity of proteases. Sigma's non-specific protease activity assay may be used as a standardized procedure to determine the activity of proteases.
JoVE Immunology and Infection
One-day Workflow Scheme for Bacterial Pathogen Detection and Antimicrobial Resistance Testing from Blood Cultures
1Department of Medical Microbiology, Maastricht University Medical Center, 2Department of Internal Medicine, Erasmus Medical Center
The design of a straightforward one-day workflow scheme for bacterial pathogen diagnostics enables the rapid recognition of bloodstream infections. The inclusion of eight clinically relevant bacterial targets and their antibiotic resistance profiles offers the clinician an initial insight on the same day, which can lead to more adequate therapy.
JoVE Clinical and Translational Medicine
A Swine Model of Neonatal Asphyxia
1Departments of Pediatrics, Pharmacology and Surgery, University of Alberta, 2Department of Surgery, University of Alberta
Large animal models have good translational values in the examination of physiology and pharmacology of neonatal asphyxia. Using newborn piglets, we develop an experimental protocol to simulate neonatal asphyxia which has advantages of studying the systemic and regional hemodynamics, oxygen transport with biochemical and pathologic pathways and correlations.
JoVE General
ReAsH/FlAsH Labeling and Image Analysis of Tetracysteine Sensor Proteins in Cells
The biarsenical dyes FlAsH and ReAsH bind specifically to tetracysteine motifs in proteins and can selectively label proteins in live cells. Recently this labeling strategy has been used to develop sensors for different protein conformations or oligomeric states. We describe the labeling approach and methods to quantitatively analyze binding.
JoVE General
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.
JoVE Bioengineering
Directed Cellular Self-Assembly to Fabricate Cell-Derived Tissue Rings for Biomechanical Analysis and Tissue Engineering
Biomedical Engineering Department, Worcester Polytechnic Institute
This article outlines a versatile method to create cell-derived tissue rings by cellular self-assembly. Smooth muscle cells seeded into ring-shaped agarose wells aggregate and contract to form robust three-dimensional (3D) tissues within 7 days. Millimeter-scale tissue rings are conducive to mechanical testing and serve as building blocks for tissue assembly.
JoVE General
Determination of Lipid Raft Partitioning of Fluorescently-tagged Probes in Living Cells by Fluorescence Correlation Spectroscopy (FCS)
1Centre de Recherche de l’Institut du Cerveau et de la Moelle Épinière, Hôpital de la Pitié-Salpêtrière, 2Institut des Sciences Moléculaires d'Orsay, Université Paris-Sud, 3Centre de Photonique Biomédicale du Centre Laser, Université Paris-Sud
A technique to probe the lipid raft partitioning of fluorescent proteins at the plasma membrane of living cells is described. It takes advantage of the disparity in diffusion times of proteins located inside or outside of lipid rafts. Acquisition can be performed dynamically in control conditions or after drug addition.
JoVE Application Notes
LookOut Mycoplasma Elimination Kit - ADVERTISEMENT
Product Management, Sigma-Aldrich
The LookOut Mycoplasma elimination kit combines biological agents that reliably and completely eliminate mycoplasma contamination with minimal cytotoxic effect on cells.
JoVE Immunology and Infection
Detection of Bacteria Using Fluorogenic DNAzymes
1Department of Biochemistry and Biomedical Sciences, McMaster University, 2Department of Chemistry and Chemical Biology, McMaster University
We have recently reported a novel approach for generating fluorogenic DNAzyme probes that can be applied to set up a simple, "mix-and-read" fluorescent assay for bacterial detection. These special DNA probes catalyze the cleavage of a chromophore-modified DNA-RNA chimeric substrate in the presence of crude extracellular mixture (CEM) produced by a specific bacterium, thereby translating bacterial detection into fluorescence signal generation. In this report we will describe key experimental procedures where a specific DNAzyme probe denoted "RFD-EC1" is employed for the detection of the model bacterium, Escherichia coli (E. coli).
JoVE Bioengineering
Multiparametric Optical Mapping of the Langendorff-perfused Rabbit Heart
Department of Biomedical Engineering, Washington University in St. Louis
This article describes the basic procedures for conducting optical mapping experiments in the Langendorff-perfused rabbit heart using the panoramic imaging system, and the dual (voltage and calcium) imaging modality.
JoVE General
Detection and Isolation of Viable Mouse IL-17-Secreting T Cells
This procedure describes the detection and isolation of mouse TH17 leukocytes that actively secrete IL-17 upon stimulation.
JoVE Bioengineering
Combinatorial Synthesis of and High-throughput Protein Release from Polymer Film and Nanoparticle Libraries
Department of Chemical and Biological Engineering, Iowa State University
This method describes the combinatorial synthesis of biodegradable polyanhydride film and nanoparticle libraries and the high-throughput detection of protein release from these libraries.
JoVE General
Multiplex PCR and Reverse Line Blot Hybridization Assay (mPCR/RLB)
Centre for Infectious Diseases and Microbiology, University of Sydney
An inexpensive, high throughput method for simultaneous detection of up to 43 molecular targets is described. Applications of mPCR/RLB include microbial typing and detection of multiple pathogens from clinical samples.
JoVE Bioengineering
In vitro Assembly of Semi-artificial Molecular Machine and its Use for Detection of DNA Damage
1Neurosurgery, Baylor College of Medicine, 2Michael E. DeBakey Veterans Affairs Medical Center, 3Molecular & Cellular Biology, Baylor College of Medicine
We demonstrate the assembly and application of a molecular-scale device powered by a topoisomerase protein. The construct is a bio-molecular sensor which labels two major types of DNA breaks in tissue sections by attaching two different fluorophores to their ends.
JoVE Bioengineering
Optical Mapping of Action Potentials and Calcium Transients in the Mouse Heart
Department of Biomedical Engineering, Washington University in St. Louis
This paper details the dissection procedure, instrumental setup, and experimental conditions during optical mapping of transmembrane potential (Vm) and intracellular calcium transient (CaT) in intact isolated Langendorff perfused mouse hearts.
JoVE Clinical and Translational Medicine
Normothermic Cardiac Arrest and Cardiopulmonary Resuscitation: A Mouse Model of Ischemia-Reperfusion Injury
1Department of Anesthesiology and Perioperative Medicine, Oregon Health & Sciences University, 2Department of Pharmacology, University of Colorado Denver
A powerful model for perioperative and critical care related acute kidney injury is presented. Using whole body hypoperfusion induced by cardiac arrest it is possible to nearly replicate the histologic and functional changes of clinical AKI.
JoVE General
Titration of Human Coronaviruses Using an Immunoperoxidase Assay
Laboratory of Neuroimmunovirology, INRS-Institut Armand-Frappier
In this video, we demonstrate an alternative method for detection and titering of viruses using an enzymatic antigen detection technique known as an immunoperoxidase assay. Here, we will show you how to collect your viral samples, prepare the cells for testing, and finally the immunoperoxidase assay using serial dilutions to determine the viral titer.
JoVE Immunology and Infection
ampliPHOX Colorimetric Detection on a DNA Microarray for Influenza
InDevR, Inc.
ampliPHOX colorimetric detection technology is presented as an inexpensive alternative to fluorescence detection for microarrays. Based on photopolymerization, ampliPHOX produces solid polymer spots visible to the naked eye in just a few minutes. Results are then imaged and automatically interpreted with a simple yet powerful software package.
JoVE Neuroscience
Detection of Neuritic Plaques in Alzheimer's Disease Mouse Model
Department of Neuroscience, The University of British Columbia
One of the pathological characteristics of AD is the formation of Amyloid β protein positive neuritic plaques. In this protocol we describe two methods to detect neuritic plaques in transgenic AD model mice: immunohistochemical detection using the ABC and DAB method and fluorescent detection using thioflavin S staining method.
JoVE General
Synthesis of an In vivo MRI-detectable Apoptosis Probe
1Division of Cardiovascular Medicine, Department of Medicine, Stanford University Medical Center, 2Division of Cardiology, Department of Medicine, University of California, San Francisco, 3San Francisco VAMC
Early detection of apoptosis may identify at-risk cell populations in a variety of diseases. Here we demonstrate a method to link an early apoptosis-detection protein (Annexin V) to a MRI-detectable iron oxide nanoparticle (SPIO). This method may be extended to other proteins of interest to generate MRI-detectable molecular imaging probes.
JoVE Bioengineering
On-chip Isotachophoresis for Separation of Ions and Purification of Nucleic Acids
Mechanical Engineering, Stanford University
Isotachophoresis (ITP) is a robust electrokinetic separation and preconcentration technique with applications ranging from toxin detection to sample preparation. We review the physical principles of ITP and the methodology of applying this technique to two specific example applications: separation and detection of small molecules and purification of nucleic acids from cell culture lysate.
JoVE General
Rapid Homogeneous Detection of Biological Assays Using Magnetic Modulation Biosensing System
1Department of Physical Electronics, Faculty of Engineering, Tel Aviv University, 2Department of Biomedical Engineering, Washington University in St. Louis, 3Department of Biological Sciences, University of Illinois, 4Department of Cell Research and Immunology, Tel Aviv University
Magnetic modulation biosensing system is utilized to rapidly, sensitively and simply detect biological assays, such as DNA molecules and proteins.
JoVE General
Immunofluorescent Detection of Two Thymidine Analogues (CldU and IdU) in Primary Tissue
We have derived a strategy to detect sequential incorporation of thymidine analogues (CldU and IdU) into tissues of adult mice to quantify two successive rounds of cell division. This strategy is useful to detect cell turnover of long-lived tissues, oncogenic transformation, or transit-amplifying cells.
JoVE Immunology and Infection
Monitoring Immune Cells Trafficking Fluorescent Prion Rods Hours after Intraperitoneal Infection
Department of Microbiology, Immunology and Pathology, Colorado State University
Here we describe a novel assay for monitoring prion uptake and trafficking by immune cells immediately following intraperitoneal inoculation by purifying and fluorescently labeling aggregated prion rods from infected brain material then monitoring their uptake and movement from the injection site and characterizing the cells mediating these events.
JoVE Immunology and Infection
Ex vivo Expansion of Tumor-reactive T Cells by Means of Bryostatin 1/Ionomycin and the Common Gamma Chain Cytokines Formulation
1Department of Microbiology & Immunology, Virginia Commonwealth University- Massey Cancer Center, 2Department of Internal Medicine, Virginia Commonwealth University- Massey Cancer Center, 3Department of Surgery, Virginia Commonwealth University- Massey Cancer Center
An efficient protocol for the ex vivo expansion of tumor-reactive T cells from tumor-draining lymph nodes or other secondary lymphoid tissues of tumor-bearing hosts is described. This protocol selectively expands tumor-specific T cells for use in adoptive immunotherapy of breast cancer.
JoVE Immunology and Infection
RNA Interference in Ticks
1Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, 2(CSIC-UCLM-JCCM), Instituto de Investigación en Recursos Cinegéticos IREC
A method for RNA interference (RNAi) by injection of dsRNA into unfed ticks is described. RNAi is the most widely used gene-silencing technique in ticks where the use of other methods of genetic manipulation has been limited.
JoVE Neuroscience
Organotypic Cerebellar Cultures: Apoptotic Challenges and Detection
1Laboratory of Genetics, The Salk Institute for Biological Studies, 2Clayton Foundation Laboratories for Peptide Biology, The Salk Institute for Biological Studies
This method describes the generation of organotypic cerebellar cultures and the effect of certain apoptotic stimuli on the viability of different cerebellar cell types.
JoVE Immunology and Infection
Generation and Labeling of Murine Bone Marrow-derived Dendritic Cells with Qdot Nanocrystals for Tracking Studies
1Molecular and Cell Biology Program, Ohio University, 2Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, 3Department of Biomedical Engineering, Russ College of Engineering and Technology, Ohio University
Dendritic cells uptake antigens and migrate towards immune organs to present processed antigens to T cells. Qdot nanocrystal labeling provides a long-lasting and stable fluorescent signal. This allows tracking of dendritic cells to different organs by fluorescent microscopy.
JoVE General
Isolation and Characterization of RNA-Containing Exosomes
This paper demonstrates methods for the isolation, purification and detection of exosomes, as well as techniques for analysis of their molecular content. These methods are adaptable for exosome isolation from both cell culture media and biological fluids, and can beyond analysis of molecular content also be useful in functional studies.
JoVE General
Glycan Profiling of Plant Cell Wall Polymers using Microarrays
1Australian Centre of Excellence in Plant Cell Walls, School of Botany, University of Melbourne, 2Plant Cell Biology Research Centre, School of Botany, University of Melbourne, 3CSIRO Plant Industry, Black Mountain Laboratories, 4Department of Plant Biology and Biotechnology, University of Copenhagen
A technique called Comprehensive Microarray Polymer Profiling (CoMPP) for the characterisation of plant cell wall glycans is described. This method combines the specificity of monoclonal antibodies directed to defined glycan-epitopes with a miniature microarray analytical platform allowing screening of glycan occurrence in a broad range of biological contexts.
JoVE Neuroscience
Experimental Methods for Testing the Effects of Neurotrophic Peptide, ADNF-9, Against Alcohol-induced Apoptosis during Pregnancy in C57BL/6 Mice
Department of Pharmacology, College of Pharmacy and Pharmaceutical Sciences, University of Toledo
The experimental designs proposed here focus on studying the effects of alcohol exposure in apoptosis and the application of neurotrophic peptide during pregnancy in fetal brain. A detailed description from the breeding to the collection of fetal brains is described. Techniques for determination of apoptosis are also described in detail.
JoVE General
In vivo Liver Endocytosis Followed by Purification of Liver Cells by Liver Perfusion
Department of Biochemistry, University of Nebraska, Lincoln
The study of liver sinusoidal endothelial cells (SECs) must be performed with primary cells obtained from the animal as no cell lines exist. This method relies on liver digestion and differential centrifugation for SEC purification for subsequent culturing and experimentation.
JoVE Immunology and Infection
Oral Transmission of Listeria monocytogenes in Mice via Ingestion of Contaminated Food
Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky
This paper describes a novel method for oral infection of mice using Listeria monocytogenes-contaminated food. The protocol can readily be adapted for use with other food borne bacterial pathogens.
JoVE Clinical and Translational Medicine
High Throughput Sequential ELISA for Validation of Biomarkers of Acute Graft-Versus-Host Disease
Pediatric Blood and Marrow Transplant Program, University of Michigan
High throughput validation of multiple candidate biomarkers can be performed by sequential ELISA in order to minimize freeze/thaw cycles and use of precious plasma samples. Here, we demonstrate how to sequentially perform ELISAs for six different validated plasma biomarkers1-3 of graft-versus-host disease (GVHD)4 on the same plasma sample.
JoVE Bioengineering
Bacterial Detection & Identification Using Electrochemical Sensors
1Research Service, Veterans Affairs Greater Los Angeles Healthcare System, 2Department of Urology, The David Geffen School of Medicine, University of California, Los Angeles, 3GeneFluidics, 4Division of Infectious Diseases, Veterans Affairs Greater Los Angeles Healthcare System, 5Department of Microbiology, Immunology & Molecular Genetics, University of California, Los Angeles
We describe an electrochemical sensor assay method for rapid bacterial detection and identification. The assay involves a sensor array functionalized with DNA oligonucleotide capture probes for ribosomal RNA (rRNA) species-specific sequences. Sandwich hybridization of target rRNA with the capture probe and a horseradish peroxidase-linked DNA oligonucleotide detector probe produces a measurable amperometric current.
JoVE Bioengineering
Fabrication of Electrochemical-DNA Biosensors for the Reagentless Detection of Nucleic Acids, Proteins and Small Molecules
1Department of Chemistry and Biochemistry, University Of California Santa Barbara, 2Department of Chemistry and Biochemistry, Program in BioMolecular Science and Engineering, University Of California Santa Barbara
"E-DNA" sensors, reagentless, electrochemical biosensors that perform well even when challenged directly in blood and other complex matrices, have been adapted to the detection of a wide range of nucleic acid, protein and small molecule analytes. Here we present a general procedure for the fabrication and use of such sensors.
JoVE Bioengineering
Biosensor for Detection of Antibiotic Resistant Staphylococcus Bacteria
1Department of Anatomy, Physiology and Pharmacology, College of Veterinary Medicine, Auburn University, 2Clinical Research Laboratory, 81st Medical Group, Keesler Air Force Base
Lytic phage biosensors and antibody beads are able to discriminate between methicillin resistant (MRSA) and sensitive staphylococcus bacteria. The phages were immobilized by a Langmuir-Blodgett method onto a surface of a quartz crystal microbalance sensor and worked as broad range staphylococcus probes. Antibody beads recognize MRSA.
JoVE Bioengineering
Detection and Isolation of Circulating Melanoma Cells using Photoacoustic Flowmetry
We have developed a flow cytometer using laser induced ultrasound to detect circulating melanoma cells as an early indicator of metastatic disease.
JoVE Immunology and Infection
High-throughput Detection Method for Influenza Virus
1Laboratory of Molecular Immunology and Immunotherapy, Blood Research Institute, 2Department of Microbiology, Mount Sinai School of Medicine, 3Laboratory of Molecular Genetics, Blood Research Institute, 4City of Milwaukee Health Department Laboratory, 5Division of Hematology-Oncology/BMT, Children's Hospital of Wisconsin, Medical College of Wisconsin, 6Division of Hematology and Oncology, Dept Medicine, Medical College of Wisconsin
This method describes the use of Infrared dye based imaging system for detection of H1N1 in bronchioalveolar lavage (BAL) fluid of infected mice at a high sensitivity. This methodology can be performed in a 96- or 384-well plate, requires <10 μl volume of test material and has the potential for concurrent screening of multiple pathogens.
JoVE Clinical and Translational Medicine
Intraoperative Detection of Subtle Endometriosis: A Novel Paradigm for Detection and Treatment of Pelvic Pain Associated with the Loss of Peritoneal Integrity
1Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Greenville Hospital System, 2Department of Pathology, Duke University Health System, 3Department of Obstetrics and Gynecology, Division of Reproductive Endocrinology and Infertility, Duke University
Loss of peritoneal integrity provides a new paradigm to understand and treat chronic pelvic pain in women with mild forms of endometriosis and can be easily detected using intraoperative instillation of dye at the time of laparoscopy.
JoVE Bioengineering
Biomolecular Detection employing the Interferometric Reflectance Imaging Sensor (IRIS)
1Department of Electrical and Computer Engineering, Boston University, 2Department of Biomedical Engineering, Boston University, 3Center for Advanced Genomics Technology, Boston University, 4Department of Medicine, Section of Infectious Diseases, Boston University School of Medicine, 5Department of Microbiology, Boston University School of Medicine, 6CNR (National Research Council), Istituto di Chimica del Riconoscimento Molecolare
Quantitative, high-throughput, real-time, and label-free biomolecular detection (DNA, protein, etc.) on SiO2 surfaces can be achieved using a simple interferometric technique which relies on LED illumination, minimal optical components, and a camera. The Interferometric Reflectance Imaging Sensor (IRIS) is inexpensive, simple to use, and amenable to microarray formats.
JoVE Immunology and Infection
Diagnosing Pulmonary Tuberculosis with the Xpert MTB/RIF Test
1Institute for Infectious Diseases, University of Bern, 2MCL Laboratories Inc.
The Xpert MTB/RIF test integrates sample decontamination, hands-free operation, on-board sample processing, and ultra-sensitive hemi-nested PCR for the simultaneous detection of Mycobacterium tuberculosis and rifampicin resistance, either in expectorated sputum or concentrated sputum sediments, in approximately two hours. Testing is standardized and requires only moderate laboratory infrastructure and training.
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