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Heart Rate: The number of times the Heart ventricles contract per unit of time, usually per minute.

Measuring Vital Signs

JoVE 10107

Source: Meghan Fashjian, ACNP-BC, Beth Israel Deaconess Medical Center, Boston MA

The vital signs are objective measurements of a patient's clinical status. There are five commonly accepted vital signs: blood pressure, heart rate, temperature, respiratory rate, and oxygen saturation. In many practices, pain is considered the sixth vital sign and should regularly be documented in the same location as the other vital signs. However, the pain scale is a subjective measurement and, therefore, has a different value according to each individual patient. The vital signs assessment includes estimation of heart rate, blood pressure (demonstrated in a separate video), respiratory rate, temperature, oxygen saturation, and the presence and severity of pain. The accepted ranges for vital signs are: heart rate (HR), 50-80 beats per minute (bpm); respiratory rate (RR), 14-20 bpm; oxygen saturation (SaO2), > 92%; and average oral temperature, ~98.6 °F (37 °C) (average rectal and tympanic temperatures are ~1° higher, and axillary temperature is ~1° lower compared to the average oral temperature). Vital signs serve as the first clue that something may be amiss with a patient, especially if the patient is unable to communicate. Although there are

 Physical Examinations I

Physiological Correlates of Emotion Recognition

JoVE 10297

Source: Laboratories of Jonas T. Kaplan and Sarah I. Gimbel—University of Southern California

The autonomic nervous system (ANS) controls the activity of the body's internal organs and regulates changes in their activity depending on the current environment. The vagus nerve, which innervates many of the internal organs, is an important part of the system. When our brain senses danger, vagal tone is inhibited, leading to a set of changes in the body designed to make us more prepared to fight or flee; for example, our heart rate increases, our pupils dilate, and we breath more quickly. Conversely, when the vagal system is activated, these physiological responses are inhibited, leading to a calmer state. The vagus nerve, then, acts as a kind of "brake" on our arousal. One interesting consequence of this calmer state is that it tends to promote social interaction-when we are not tensed and afraid of our immediate environment we are instead receptive to interacting with others. Poor functioning of this regulatory mechanism, therefore, may be associated with difficulties in social behavior. One index of autonomic regulation is heart rate variability (HRV). HRV is a measure of how much the gap between one beat and the next varies over time. High HRV means there are continual fluctuations in the


Fear Conditioning

JoVE 5417

Fear Conditioning is a type of learning in which an association is established between a negative unpleasant event and a harmless stimulus. This leads to a fear of the harmless stimulus. This process is largely mediated by the amygdala, which is a brain region involved in emotions and stress reactions. Fear conditioning can be utilized in several ways to understand different aspects of learning and memory. This video presents an overview of the principles behind fear conditioning, discusses the equipment and a generalized procedure used for this type of experiment. Finally, we'll review some real world applications of fear conditioning in behavioral neuroscience research today.

 Behavioral Science

Cardiac Magnetic Resonance Imaging

JoVE 10393

Source: Frederick W. Damen and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana

In this video, high field, small-bore magnetic resonance imaging (MRI) with physiological monitoring is demonstrated to acquire gated cine loops of the murine cardiovascular system. This procedure provides a basis for assessing left-ventricular function, visualizing vascular networks, and quantifying motion of organs due to respiration. Comparable small animal cardiovascular imaging modalities include high-frequency ultrasound and micro-computed tomography (CT); however, each modality is associated with trade-offs that should be considered. While ultrasound does provide high spatial and temporal resolution, imaging artifacts are common. For example, dense tissue (i.e., the sternum and ribs) can limit imaging penetration depth, and hyperechoic signal at the interface between gas and liquid (i.e., pleura surrounding the lungs) can blur contrast in nearby tissue. Micro-CT in contrast does not suffer from as many in-plane artifacts, but does have lower temporal resolution and limited soft-tissue contrast. Furthermore, micro-CT uses X-ray radiation and often requires the use of contrast agents to visualize vasculature, both of which are known to cause side effects at high doses incl

 Biomedical Engineering

Acquisition and Analysis of an ECG (electrocardiography) Signal

JoVE 10473

Source: Peiman Shahbeigi and Sina Shahbazmohamadi, Biomedical Engineering Department, University of Connecticut, Storrs, Connecticut

An electrocardiograph is a graph recorded by electric potential changes occurring between electrodes placed on a patient's torso to demonstrate cardiac activity. An ECG signal tracks heart rhythm and many cardiac diseases, such as poor blood flow to the heart and structural abnormalities. The action potential created by contractions of the heart wall spreads electrical currents from the heart throughout the body. The spreading electrical currents create different potentials at points in the body, which can be sensed by electrodes placed on the skin. The electrodes are biological transducers made of metals and salts. In practice, 10 electrodes are attached to different points on the body. There is a standard procedure for acquiring and analyzing ECG signals. A typical ECG wave of a healthy individual is as follows: Figure 1. ECG wave. The "P" wave corresponds to atrial contraction, and the "QRS" complex to the contraction of the ventricles. The "QRS' complex is much larger than the "P" wave due

 Biomedical Engineering

Mouse Genotyping

JoVE 5160

Even though the human genome was mapped over 10 years ago, scientists are still far from understanding the function of every human gene! One way to evaluate how a gene functions is to disrupt the sequence encoding it and then evaluate the impact of this change (the phenotype) on the animal’s biology. This approach is commonly used in the mouse (Mus musculus), since it shares a high degree of genetic similarity with humans. To track the animals bearing genetic changes over several generations, it is necessary to screen the DNA of each mouse in a process known as genotyping. This video provides an overview of the theory and practice behind genotyping mice. The discussion begins with the basic principles of mouse genetics, including a review of the terms homozygote, heterozygote, wildtype, mutant, and transgenic. Next, step-by-step instructions are supplied for extracting and purifying genomic DNA from mouse tissue. Examples are provided demonstrating how to interpret genotyping results, as well as how to keep track of mice with the desired genotype. Finally, some representative applications of the genotyping procedure will be presented in order to demonstrate why this common technique is so essential to mouse research.

 Biology II

Combined SPECT and CT Imaging to Visualize Cardiac Functionality

JoVE 10396

Source: Alycia G. Berman, James A. Schaber, and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana

Here we will demonstrate the fundamentals of single-photon emission computed tomography/computed tomography (SPECT/CT) imaging using mice. The technique involves injecting a radionuclide into a mouse, imaging the animal after it is distributed throughout the body, and then reconstructing the produced images to create a volumetric dataset. This can provide information about anatomy, physiology, and metabolism to improve disease diagnosis and monitor its progression. In terms of collected data, SPECT/CT provides similar information as positron emission tomography (PET)/CT. However, the underlying principles of these two techniques are fundamentally different since PET requires the detection of two gamma photons, which are emitted in opposite directions. In contrast, SPECT imaging directly measures radiation via a gamma camera. As a result, SPECT imaging has lower spatial resolution than PET. However, it is also less expensive because the SPECT radioactive isotopes are more readily available. SPECT/CT imaging provides both noninvasive metabolic and anatomical information that can be useful for a wide variety of applications.

 Biomedical Engineering

Anesthesia Induction and Maintenance

JoVE 10263

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN

The Guide for the Care and Use of Laboratory Animals ("The Guide") states that pain assessment and alleviation are integral components of the veterinary care of laboratory animals.1 The definition of anesthesia is the loss of feeling or sensation. It is a dynamic event involving changes in anesthetic depth with respect to an animal's metabolism, surgical stimulation, or variations in the external environment.

 Lab Animal Research

Genetic Engineering of Model Organisms

JoVE 5327

Transgenesis, or the use of genetic engineering to alter gene expression, is widely used in the field of developmental biology. Scientists use a number of approaches to alter the function of genes to understand their roles in developmental processes. This includes replacement of a gene with a nonfunctional copy, or adding a visualizable tag to a gene that allows the resultant fusion protein to be tracked throughout development. In this video, the viewers will learn about the principles behind transgenesis, as well as the basic steps for introducing genetic constructs into an animal and targeting genes of interest. This is followed by the discussion of a protocol to create knockout mice. Lastly, some specific applications of transgenic technologies in the field of developmental biology will be reviewed.

 Developmental Biology

Quantitative Strain Mapping of an Abdominal Aortic Aneurysm

JoVE 10480

Authors: Hannah L. Cebull1, Arvin H. Soepriatna1, John J. Boyle2 and Craig J. Goergen1 1Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 2Mechanical Engineering & Materials Science, Washington University in St. Louis, St Louis, Missouri

The mechanical behavior of soft tissues, such as blood vessels, skin, tendons, and other organs, are strongly influenced by their composition of elastin and collagen, which provide elasticity and strength. The fiber orientation of these proteins depends on the type of soft tissue and can range from a single preferred direction to intricate meshed networks, which can become altered in diseased tissue. Therefore, soft tissues often behave anisotropically on the cellular and organ level, creating a need for three-dimensional characterization. Developing a method for reliably estimating strain fields within complex biological tissues or structures is important to mechanically characterize and understande disease. Strain represents how soft tissue relatively deforms over time, and it can be described mathematically through various estimations. Acquiring image data over time allows deformation and strain to be estimated. However, all medica

 Biomedical Engineering

Normothermic Ex Situ Heart Perfusion in Working Mode: Assessment of Cardiac Function and Metabolism

1Department of Surgery, Faculty of Medicine, University of Alberta, 2Department of Pediatrics, Faculty of Medicine, University of Alberta, 3Department of Biomedical Engineering, Faculty of Medicine, University of Alberta, 4Department of Mechanical Engineering, Faculty of Engineering, University of Alberta, 5Department of Chemical and Materials Engineering, Faculty of Engineering, University of Alberta, 6Department of Physiology, Faculty of Medicine, University of Alberta, 7Canadian National Transplant Research Program

Video Coming Soon

JoVE 58430

 JoVE In-Press

Modeling Social Stress

JoVE 5429

Stress negatively affects our quality of life. In particular, some individuals experience social stress when placed in a social environment that they are unfamiliar with or have difficulty adjusting to. Since it is hard to examine mechanisms of social stress in humans, modeling this condition in animals may help scientist in developing new therapies for treating this commonly encountered problem. This science education video begins by discussing the known anatomy and physiology behind stress response. Then, we explain a well-established paradigm for modeling social stress in rodents, the Resident-Intruder task. In the applications section, we review some example studies in which response to stress is measured.

 Behavioral Science

Percutaneous Contrast Echocardiography-guided Intramyocardial Injection and Cell Delivery in a Large Preclinical Model

1Institute for Cardiovascular and Metabolic Research, School of Biological Sciences, University of Reading, 2Departamento de Medicina y Cirugía Animal, Facultad de Veterinaria, Universidad de Murcia, 3Institute of Virology and Immunology (IVI), 4Departamento de Anatomía y Anatomía Comparada, Facultad de Veterinaria, Universidad de Murcia, 5Unidad de Trasplante Hematopoyético y Terapia Celular, Departamento de Hematología, Hospital Universitario Virgen de la Arrixaca, IMIB, Universidad de Murcia

JoVE 56699


Photoacoustic Tomography to Image Blood and Lipids in the Infrarenal Aorta

JoVE 10395

Source: Gurneet S. Sangha and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana

Photoacoustic tomography (PAT) is an emerging biomedical imaging modality that utilizes light generated acoustic waves to obtain compositional information from tissue. PAT can be used to image blood and lipid components, which is useful for a wide variety of applications, including cardiovascular and tumor imaging. Currently used imaging techniques have inherent limitations that restrict their use with researchers and physicians. For example, long acquisition times, high costs, use of harmful contrast, and minimal to high invasiveness are all factors that limit the use of various modalities in the laboratory and clinic. Currently, the only comparable imaging techniques to PAT are emerging optical techniques. But these also have disadvantages, such as limited depth of penetration and the need for exogenous contrast agents. PAT provides meaningful information in a rapid, noninvasive, label-free manner. When coupled with ultrasound, PAT can be used to obtain structural, hemodynamic, and compositional information from tissue, thereby complementing currently used imaging techniques. The advantages of PAT illustrate its capabilities to make an impact in both the preclinical and clinical

 Biomedical Engineering

Light-sheet Fluorescence Microscopy to Capture 4-Dimensional Images of the Effects of Modulating Shear Stress on the Developing Zebrafish Heart

1Department of Bioengineering, The University of Texas at Arlington, 2Department of Medicine (Cardiology) and Bioengineering, UCLA, 3College of Health Science and Environmental Engineering, Shenzhen Technology University

JoVE 57763


High-frequency Ultrasound Imaging of the Abdominal Aorta

JoVE 10397

Authors: Amelia R. Adelsperger, Evan H. Phillips, and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana

High-frequency ultrasound systems are used to acquire high resolution images. Here, the use of a state-of-the-art system will be demonstrated to image the morphology and hemodynamics of small pulsatile arteries and veins found in mice and rats. Ultrasound is a relatively inexpensive, portable, and versatile method for the noninvasive assessment of vessels in humans as well as large and small animals. These are several key advantages that ultraound offers compared to other techniques, such as computed tomography (CT), magnetic resonance imaging (MRI), and near-infrared fluorescence tomography (NIRF). CT requires ionizing radiation and MRI can be prohibitively expensive and even impractical in some scenarios. NIRF, on the other hand, is limited by the penetration depth of light required to excite the fluorescent contrast agents. Ultrasound has limitations in terms of imaging depth; however, this may be overcome by sacrificing resolution and using a lower frequency transducer. Abdominal gas and excess body weight can severely diminish image quality. In the first case, the propagation of sound waves is limited, while in the lat

 Biomedical Engineering

Shunt Surgery, Right Heart Catheterization, and Vascular Morphometry in a Rat Model for Flow-induced Pulmonary Arterial Hypertension

1Center for Congenital Heart Diseases, Department of Pediatric Cardiology, Beatrix Children's Hospital, University Medical Center Groningen, University of Groningen, 2Research and Development Facility, University Medical Center Groningen, University of Groningen

JoVE 55065


Observational Study Protocol for Repeated Clinical Examination and Critical Care Ultrasonography Within the Simple Intensive Care Studies

1Department of Critical Care, University of Groningen, University Medical Centre Groningen, 2Department of Anesthesiology, University of Groningen, University Medical Centre Groningen, 3Department of Radiology, University of Groningen, University Medical Centre Groningen, 4Department of Cardiology, University of Groningen, University Medical Centre Groningen, 5Division of Nephrology, Department of Internal Medicine, University of Groningen, University Medical Centre Groningen

Video Coming Soon

JoVE 58802

 JoVE In-Press

Considerations for Rodent Surgery

JoVE 10285

Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN

The Guide for the Care and Use of Laboratory Animals1 dictates that rodent survival surgery be performed aseptically. Aseptic technique utilizes specific practices that minimize the contamination of the surgical site, including patient preparation, surgeon preparation, sterilization of instruments and other supplies, and the use of a clean and controlled environment. Presurgical planning, intraoperative monitoring, and postoperative care are essential for successful recovery of animals from survival surgeries.

 Lab Animal Research

Technique to Collect Fungiform (Taste) Papillae from Human Tongue

1Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, 2Department of Internal Medicine and Department of Psychiatry, School of Medicine, Washington University in St. Louis, 3Veterans Affairs Medical Center, 4School of Dental Medicine, Department of Biochemistry, University of Pennsylvania-School of Medicine, 5Monell Chemical Senses Center, 6Monell Chemical Senses Center

JoVE 2201


Evaluation of a Novel Laser-assisted Coronary Anastomotic Connector - the Trinity Clip - in a Porcine Off-pump Bypass Model

1Department of Cardiothoracic Surgery, University Medical Center Utrecht, 2Vascular Connect b.v., 3Department of Neurosurgery, University Medical Center Utrecht, 4Department of Experimental Cardiology, University Medical Center Utrecht

JoVE 52127


An Introduction to the Laboratory Mouse: Mus musculus

JoVE 5129

Mice (Mus musculus) are an important research tool for modeling human disease progression and development in the lab. Despite differences in their size and appearance, mice share a distinct genetic similarity to humans, and their ability to reproduce and mature quickly make them efficient and economical candidate mammals for scientific study.

This video provides a brief overview of mice, both as organisms and in terms of their many advantages as experimental models. The discussion features an introduction to common laboratory mouse strains, including the nude mouse, whose genetic makeup renders them both hairless and immunodeficient. A brief history of mouse research is also offered, ranging from their first use in genetics experiments to Nobel prize-winning discoveries in immunology and neurobiology. Finally, representative examples of the diverse types of research that can be performed in mice are presented, such as classic behavioral tests like the Morris water maze and in-depth investigations of mammalian embryonic development.

 Biology II

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