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Gastrointestinal Tract: Generally refers to the digestive structures stretching from the Mouth to Anus, but does not include the accessory glandular organs (Liver; Biliary tract; Pancreas).

Preparing and Administering Enteric Tube Medications

JoVE 10287

Source: Madeline Lassche, MSNEd, RN and Katie Baraki, MSN, RN, College of Nursing, University of Utah, UT



An enteric tube is a tube that is inserted and passed into the stomach or intestines. Enteric tubes serve multiple purposes, including stomach decompression (through the removal of air, gastric contents, and secretions),…

 Nursing Skills

Blood Flow

JoVE 10888

Blood is pumped by the heart into the aorta, the largest artery in the body, and then into increasingly smaller arteries, arterioles, and capillaries. The velocity of blood flow decreases with increased cross-sectional blood vessel area. As blood returns to the heart through venules and veins, its velocity increases. The movement of blood is encouraged by smooth muscle in the vessel walls, the movement of skeletal muscle surrounding the vessels, and one-way valves that prevent backflow. Somewhat counterintuitively, the velocity of blood flow decreases as it enters blood vessels with smaller diameters. If a hose is squeezed, decreasing its diameter, water will squirt out faster and harder, but this does not occur when blood moves into blood vessels with smaller diameters. This is because blood does not simply move from one blood vessel into a smaller one, but travels from a blood vessel into multiple smaller blood vessels. The total cross-sectional area of these smaller blood vessels is greater than that of the original blood vessel. Additionally, the decreased diameter of individual vessels creates increased resistance. Therefore, as blood enters smaller blood vessels, it slows down, providing time for gas exchange to occur through the walls of small capillaries. Blood flow is directed by vasodilation and vasoconstriction. Chemical signals can cause blood

 Core: Circulatory and Pulmonary Systems

Abdominal Exam I: Inspection and Auscultation

JoVE 10088

Source: Alexander Goldfarb, MD, Assistant Professor of Medicine, Beth Israel Deaconess Medical Center, MA


Gastrointestinal disease accounts for millions of office visits and hospital admissions annually. Physical examination of the abdomen is a crucial tool in diagnosing diseases of the gastrointestinal tract; in addition, it can help…

 Physical Examinations II

Preparing and Administering Oral Tablet and Liquid Medications

JoVE 10258

Source: Madeline Lassche, MSNEd, RN and Katie Baraki, MSN, RN, College of Nursing, University of Utah, UT



Oral medications are the route most preferred by patients and are one of the most commonly used routes of medication administration by providers. Most oral preparations are taken by mouth, swallowed with fluid, and…

 Nursing Skills

What is the Immune System?

JoVE 10895

The immune system comprises diverse biological structures and processes that protect the body from disease. These processes can be classified into innate and adaptive immunity. To work effectively, the immune system needs to detect pathogens by distinguishing the body’s own structures from foreign elements. If this determination fails, autoimmune diseases occur in which the immune system reacts against the body’s own tissue. The innate immune system is the first line of defense against infection. It comprises physical barriers and a variety of cells that act quickly and non-specifically against elements that are foreign to the host (i.e., non-self). Examples of physical barriers in mammals are skin, the lining of the gastrointestinal tract, and secretions, such as mucus or saliva. Once an invader overcomes physical barriers, cells of the inflammatory response are recruited to the entry site: mast cells release a plethora of chemicals that attract other cells of the innate immune system and activates the adaptive immune system. Phagocytic cells, such as neutrophils and macrophages, ingest and destroy pathogens. Natural killer cells, a special type of white blood cell, destroy virus-infected cells. Together, cells of the innate immune system eradicate the invader or hinder its spread, and activate the adaptive immune system. How can an organism

 Core: Immune System

Pleiotropy

JoVE 10780

Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause Waardenburg Syndrome Type 4, or WS4, which can cause defects in pigmentation, hearing impairments, and an absence of intestinal contractions necessary for elimination. This diversity of phenotypes results from the expression pattern of SOX10 in early embryonic and fetal development. SOX10 is found in neural crest cells that form melanocytes, which are involved in pigmentation and also in the early development of the ear. SOX10 is also expressed in nerve tissue that eventually contributes to the enteric nervous system in the gut, which controls the contractions necessary for waste elimination. In this way, SOX10 exhibits pleiotropic effects, because it influences multiple phenotypes. Pleiotropy can arise through several mechanisms. Gene pleiotropy occurs when a gene has various functions due to encoding a product that interacts with multiple proteins or catalyzes multiple reactions. For example, in humans, an abnormal copy of the SOX10 gene, in which a region is deleted, can lead to developmental defects that include a white forelock, different-colored irises (e.g., one blue and one brown), and regions of unpigmented skin. These traits are all symptoms of a di

 Core: Classical and Modern Genetics

Preparing and Administering Subcutaneous Medications

JoVE 10234

Source: Madeline Lassche, MSNEd, RN and Katie Baraki, MSN, RN, College of Nursing, University of Utah, UT



Subcutaneous medication administration is a parenteral approach to administer small amounts of medication (less than 2 mL) into the layer of tissue just below the skin. Common medications administered via the subcutaneous …

 Nursing Skills

Compound Administration II

JoVE 10388

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



Compound administration is often an integral component of an animal study. Many factors need to be evaluated to ensure that the compound is delivered correctly. The route of administration affects the mechanisms of…

 Lab Animal Research

Bacterial Signaling

JoVE 10713

At times, a group of bacteria behaves like a community. To achieve this, they engage in quorum sensing, the perception of higher cell density that results in a shift in gene expression. Quorum sensing involves both extracellular and intracellular signaling. The signaling cascade starts with a molecule called an autoinducer (AI). Individual bacteria produce AIs that move out of the bacterial cell membrane into the extracellular space. AIs can move passively along a concentration gradient out of the cell, or be actively transported across the bacterial membrane. When cell density in the bacterial populations is low, the AIs diffuse away from the bacteria, keeping the environmental concentration of AIs low. As bacteria reproduce and continue to excrete AIs, the concentration of AIs increases, eventually reaching a threshold concentration. This threshold permits AIs to bind membrane receptors on the bacteria, triggering changes in gene expression across the whole bacterial community. Many bacteria are broadly classified as gram positive or gram negative. These terms refer to the color that the bacteria take on when treated with a series of staining solutions which were developed by Hans Christian Joachim Gram over a century ago. If bacteria pick up a purple color, they are gram-positive; if they look red, they are gram-negative. These stain colors are pic

 Core: Cell Signaling

Percussion

JoVE 10136

Source: Jaideep S. Talwalkar, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT


Simply stated, percussion refers to the striking of one object against another to produce sound. In the early 1700s, an Austrian inn-keeper's son, named Leopold Auenbrugger, discovered that he could take inventory …

 Physical Examinations I

Probiotic Studies in Neonatal Mice Using Gavage

1Department of Experimental Medicine, University of British Columbia, 2Department of Pediatrics, University of British Columbia, 3Department of Epidemiology and Pediatrics, University of Nebraska Medical Centre, 4Animal Care Services, University of British Columbia

JoVE 59074

 Immunology and Infection

In Vitro Recording of Mesenteric Afferent Nerve Activity in Mouse Jejunal and Colonic Segments

1Laboratory of Experimental Medicine and Pediatrics, Division of Gastroenterology, University of Antwerp, 2Visceral Pain Group, Discipline of Medicine, University of Adelaide, 3Department of Biomedical Sciences, University of Sheffield, 4Department of Pharmacy, Pharmacology and Postgraduate Medicine, University of Hertfordshire, 5Department of Gastroenterology and Hepatology, Antwerp University Hospital

JoVE 54576

 Neuroscience

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

1Program in Developmental Biology, Baylor College of Medicine, 2Center for Cell and Gene Therapy, Texas Children's Hospital, and Houston Methodist Hospital, Baylor College of Medicine, 3Molecular and Cellular Biology Department, Baylor College of Medicine, 4Stem Cell and Regenerative Medicine Center, Baylor College of Medicine, 5McNair Medical Institute, Baylor College of Medicine

JoVE 57599

 Developmental Biology

Multimodal Quantitative Phase Imaging with Digital Holographic Microscopy Accurately Assesses Intestinal Inflammation and Epithelial Wound Healing

1Department of Medicine B, University Hospital Münster, 2Institute of Palliative Care, University Hospital Münster, 3Biomedical Technology Center, University of Münster, 4Department of Gastroenterology, Klinikum Bielefeld

JoVE 54460

 Medicine

Isolation of Enteric Glial Cells from the Submucosa and Lamina Propria of the Adult Mouse

1Department of Internal Medicine-Gastroenterology, University of Michigan, 2Department of Molecular and Integrative Physiology, University of Michigan, 3Department of Molecular, Cellular and Developmental Biology, University of Michigan, 4Department of Gastrointestinal Surgery, The First Affiliated Hospital of Guangxi Medical University, 5Division of Gastroenterology, University of Arizona College of Medicine

JoVE 57629

 Biology
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