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Blood Vessels: Any of the tubular vessels conveying the blood (arteries, arterioles, capillaries, venules, and veins).

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

Physiology of the Circulatory System- Concept

JoVE 10625

Homeostasis

Conditions in the external environment of an organism can change rapidly and drastically. To survive, organisms must maintain a fairly constant internal environment, which involves continuous regulation of temperature, pH, and other factors. This balanced state is known as homeostasis, which describes the processes by which organisms maintain their optimal internal…

 Lab Bio

Vasodilation of Isolated Vessels and the Isolation of the Extracellular Matrix of Tight-skin Mice

1Department of Anesthesiology, Medical College of Wisconsin, 2Clement J. Zablocki Veterans Affairs Medical Center, 3Department of Surgery, Division of Pediatric Surgery, Children's Research Institute, 4Department of Orthopedic Surgery, Medical College of Wisconsin, 5Deptarment of Anesthesiology, Clement J Zblocki Veteran Affairs Medical Center, 6Department of Medicine, Division of Cardiology, Medical College of Wisconsin

JoVE 55036

 Immunology and Infection

Computational Fluid Dynamics Simulations of Blood Flow in a Cerebral Aneurysm

JoVE 10479

Source: Joseph C. Muskat, Vitaliy L. Rayz, and Craig J. Goergen, Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana


The objective of this video is to describe recent advancements of computational fluid dynamic (CFD) simulations based on patient- or animal-specific vasculature. Here,…

 Biomedical Engineering

The Blood-brain Barrier

JoVE 10841

The blood-brain barrier (BBB) refers to the specialized vasculature that provides the brain with nutrients in the blood while strictly regulating the movement of ions, molecules, pathogens, and other substances. It is composed of tightly linked endothelial cells on one side and astrocyte projections on the other. Together they provide a semipermeable barrier that protects the brain and poses unique challenges to the delivery of therapeutics. The BBB is made up of a variety of cellular components, including endothelial cells and astrocytes. These cells share a common basement membrane and together regulate the passage of components between the circulation and the interstitial fluid surrounding the brain. The first type of cellular component, specialized endothelial cells, make up the walls of the cerebral capillaries. They are connected by extremely tight and complex intercellular junctions. These junctions create a selective physical barrier, preventing simple diffusion of most substances, including average to large-sized molecules such as glucose and insulin. A second cell type, astrocytes, are a type of glial cell of the central nervous system which influences endothelial cell function, blood flow, and ion balance in the brain through interaction and close association with cerebral vasculature. They provide a direct link between the vasculature

 Core: Nervous System

Anatomy of the Circulatory System

JoVE 10885

The human circulatory system consists of blood, blood vessels that carry blood away from the heart, around the body, and back to the heart, and the heart itself, which acts as a central pump. The systemic circuit supplies blood to the whole body, the coronary circuit supplies blood to the heart, and the pulmonary circuit supplies blood flow between the heart and lungs.

Blood travels from the right atrium to the right ventricle of the heart through the tricuspid valve, then from the right ventricle to the pulmonary artery through the pulmonary valve. Pulmonary veins then carry the blood to the left atrium of the heart, from which it is carried to the left ventricle through the mitral valve. Finally, the left ventricle pumps blood to the aorta (the largest artery in the body) through the aortic valve. Arteries, which carry blood away from the heart, split and get progressively smaller, becoming arterioles and eventually a series of capillaries, the sites of gas exchange. Capillaries converge to become larger venules, and eventually merge into veins, which bring blood back to the heart. Humans have a double circulatory system, in which blood travels through the heart twice via the pulmonary and systemic circuits. First, the heart receives deoxygenated blood in its right side and then pumps it to the nearby pulmonary circuit, the capillaries that ar

 Core: Circulatory and Pulmonary Systems

Inflammation

JoVE 10902

In response to tissue injury and infection, mast cells initiate inflammation. Mast cells release chemicals that increase the permeability of adjacent blood capillaries and attract additional immune cells to the wound or site of infection. Neutrophils are phagocytic leukocytes that exit the bloodstream and engulf invading microbes. Blood clotting platelets seal the wound and fibers create a scaffold for wound healing. Macrophages engulf aging neutrophils to end the acute inflammatory response. Tissue injury and infection are the primary causes of acute inflammation. Inflammation protects the body by eliminating the cause of tissue injury and initiating the removal of cell debris resulting from the initial damage and related immune cell activity. Inflammation involves mediators of both the innate and adaptive immune system. Proper regulation of inflammation is crucial to clear the pathogen and remove cell debris without overly damaging healthy tissue in the process. If inflammatory processes are not properly regulated, chronic inflammation can arise that is often fatal. Mast cells are the first to respond to tissue injury, as they are primarily located in areas that have contact with the exterior: the skin, gut, and airways. Mast cells have an arsenal of receptors on their cell surface and can hence be activated by a wide variety of stimuli, such as mi

 Core: Immune System

Hormonal Regulation

JoVE 10893

The renin-aldosterone system is an endocrine system which guides the renal absorption of water and electrolytes, thus managing blood pressure and osmoregulation. Activation of the system begins in the kidneys with a small cluster of cells adjacent to the afferent and efferent blood vessels of the renal corpuscle. As the nephrons are filtering blood, juxtaglomerular cells monitor blood pressure. If they detect a decrease in pressure, they release the hormone renin into the bloodstream. Circulating renin interacts with angiotensinogen, a precursor protein synthesized by the liver, to create angiotensin I. A final step cleaves angiotensin I into angiotensin II, a process achieved by angiotensin-converting enzyme, or ACE, which is released by the lungs. Angiotensin II temporarily increases blood pressure by contracting smaller blood vessels. It also induces the release of aldosterone from the adrenal cortex of the kidneys. Aldosterone directly stimulates the reabsorption of sodium and the excretion of potassium by the kidneys to maintain electrolyte balance. Moreover, circulating levels of aldosterone stimulate the release of antidiuretic hormone, or ADH, by the hypothalamus in the brain. Upon reaching the kidneys, ADH upregulates aquaporin channels in the nephrons which increase the water retention in the blood vessels. The combined effects of

 Core: Regulation and Excretion

Paracrine Signaling

JoVE 10716

Paracrine signaling allows cells to communicate with their immediate neighbors via secretion of signaling molecules. The signal only triggers a response in nearby target cells as the signal molecules degrade quickly or are inactivated by nearby cells if not taken up. Prominent examples of paracrine signaling include nitric oxide signaling in blood vessels, synaptic signaling of neurons, the blood clotting system, tissue repair/wound healing, and local allergic skin reactions. One of the essential paracrine signaling molecules is the gas nitric oxide (NO). Nitric oxide is produced by a family of enzymes known as nitric oxide synthases. Blood vessels contain several layers of cells. The innermost layer of cells is the endothelium. Endothelial cells have nitric oxide synthase, which produces nitric oxide that diffuses in all directions. The nitric oxide that reaches the blood does not contribute to signaling but immediately reacts with biochemicals, such as hemoglobin. Nitric oxide molecules that diffuse in the opposite direction, towards the next layer of the blood vessel, participate in some important signaling. The layer just exterior to the endothelium is made up of smooth muscle cells. The function of smooth muscle cells is to contract. When these cells contract, they clamp down on the blood vessel, narrowing its diameter and consequently rais

 Core: Cell Signaling

Filtration

JoVE 10891

The function of the kidneys is to filter, reabsorb, secrete, and excrete. Every day the kidneys filter nearly 180 liters of blood, initially removing water and solutes but ultimately returning nearly all filtrates into circulation with the help of osmoregulatory hormones. This process removes wastes and toxins but is also crucial to maintain water and electrolyte levels. Most of these functions are performed by the tiny but numerous nephrons contained within the kidneys. Blood enters the renal corpuscle of the nephron through a glomerulus of capillaries. The capillaries are surrounded by a structure called the Bowman’s capsule which absorbs water and most solutes from the blood. The blood pressure from capillaries pushes these into the capsules. If the blood pressure is too high, as seen in hypertension, the capillaries can weaken and harden, reducing the ability of the kidney to filter the blood. The filtrate from the corpuscles empty into the proximal convoluted tubules and the descending portions of the Loop of Henle. Here nearly 70% of solutes—salt, glucose, amino acids, and bicarbonates—are reabsorbed into the surrounding capillaries. Circulating blood hormones involved in osmoregulation induce reabsorption of sodium, calcium, or more water if needed to increase or decrease blood pressure and regulate electrolytes. Sec

 Core: Regulation and Excretion

Ophthalmoscopic Examination

JoVE 10146

Source: Richard Glickman-Simon, MD, Assistant Professor, Department of Public Health and Community Medicine, Tufts University School of Medicine, MA


The simplest ophthalmoscopes consist of an aperture to look through, a diopter indicator, and a disc for selecting lenses. The ophthalmoscope is primarily used to examine the fundus, or the…

 Physical Examinations II

Macromolecules- Concept

JoVE 10590

Biomolecules

Organisms contain a wide variety of organic molecules with numerous functions which depend on the chemical structures and properties of these molecules. All organic molecules contain a carbon backbone and hydrogen atoms. The carbon atom is central in the formation of a vast variety of organic molecules ranging in size, shape and complexity; inorganic molecules on the other…

 Lab Bio

Multiple Allele Traits

JoVE 10777

Multiple allelism describes genes that exist in three or more allelic forms. Although diploid organisms, like humans, normally possess only two alleles of each gene, there are multiple alleles of many (if not most) human genes present in a population. Blood type is one example of multiple allelism. There are three alleles for blood type (HBB gene) in humans: IA, IB, and i. Sickle cell anemia, which is caused by a mutation in the gene encoding beta-globin (HBB), is one example of incomplete dominance. Two copies of the sickle cell allele are required for the disease, with sickle cell homozygotes producing stiff, crescent-shaped red blood cells that clog blood vessels. On the other hand, individuals homozygous for the normal beta-globin allele make flexible, disc-like erythrocytes that travel easily through the vasculature. However, heterozygotes that have one normal allele and one sickle cell allele make both normal (disc-shaped) and sickle-shaped red blood cells, and are said to possess the sickle cell trait. These individuals rarely suffer from complications of the disease, unless, for example, they encounter low oxygen levels. This is an example of incomplete dominance, since a heterozygote exhibits an intermediate phenotype between that of healthy and sickle-shaped cells. At the molecular lev

 Core: Classical and Modern Genetics

Allergic Reactions

JoVE 10901

We speak of an allergy when the immune system triggers a response against a benign foreign structure, like food, pollen or pet dander. These elicitors are called allergens. If the immune system of a hypersensitive individual was primed against a specific allergen, it will trigger allergic symptoms during every subsequent encounter of the allergen. Symptoms can be mild, such as hay fever, to severe, such as potentially fatal anaphylactic shock. The immune system is crucial for defending an organism against bacteria, viruses, fungi, toxins, and parasites. However, in a hypersensitive response, it can be triggered by harmless substances and cause unpleasant or potentially life-threatening overreactions, called allergies. The first step toward establishing an allergy is sensitization. For instance, an individual becomes allergic to the pollen of ragweed when, for the first time, immune cells in the respiratory passage take up the pollen and degrade the allergens into fragments. These immune cells are called antigen-presenting cells, or APCs, because they display the degraded allergen fragments on their surface. Examples of APCs are dendritic cells, macrophages and B cells. Subsequently, APCs activate encountered Type 2 helper T cells (Th2). The activated Th2 then release chemical signals (e.g., cytokines) that cause B cells to differen

 Core: Immune System

The Sympathetic Nervous System

JoVE 10840

The sympathetic nervous system—one of the two major divisions of the autonomic nervous system—is activated in times of stress. It prepares the body to meet the challenges of a demanding circumstance while inhibiting essential body functions—such as digestion—that are a lower priority at the moment.

As a student, you may have had the experience of walking into class and finding a surprise exam that you were not expecting. In the moment of realization, you may sense your gut tighten, your mouth goes dry, and your heart starts to race all of a sudden. These are signs of the sympathetic system taking over in preparation to react. While you may not be in immediate danger, the system has evolved to facilitate immediate reaction to stress or threats: blood is directed away from the digestive system and skin to increase energy supplies to muscles. Furthermore, the heart rate, and blood flow increase, and pupils dilate to maximize visual perception. At the same time, the adrenal gland releases epinephrine into the circulatory system. Your body is now primed to take action, whether that means to swiftly flee from danger or fight whatever threat may be at hand. The sympathetic nervous system can be activated by various parts of the brain, with the hypothalamus playing a particularly important role. Sympathetic instructions from the central

 Core: Nervous System

The Parasympathetic Nervous System

JoVE 10839

The parasympathetic nervous system is one of the two major divisions of the autonomic nervous system. This parasympathetic system is responsible for regulating many unconscious functions, such as heart rate and digestion. It is composed of neurons located in both the brain and the peripheral nervous system that send their axons to target muscles, organs, and glands.

Activation of the parasympathetic system tends to have a relaxing effect on the body, promoting functions that replenish resources and restore homeostasis. It is therefore sometimes referred to as the “rest and digest” system. The parasympathetic system predominates during calm times when it is safe to devote resources to basic “housekeeping” functions without a threat of attack or harm. The parasympathetic nervous system can be activated by various parts of the brain, including the hypothalamus. Preganglionic neurons in the brainstem and sacral part of the spinal cord first send their axons out to ganglia—clusters of neuronal cell bodies—in the peripheral nervous system. These ganglia contain the connections between pre- and postganglionic neurons and are located near the organs or glands that they control. From here, postganglionic neurons send their axons onto target tissues—generally smooth muscle, cardiac muscle, or glands. Typic

 Core: Nervous System

The Extracellular Matrix

JoVE 10695

In order to maintain tissue organization, many animal cells are surrounded by structural molecules that make up the extracellular matrix (ECM). Together, the molecules in the ECM maintain the structural integrity of tissue as well as the remarkable specific properties of certain tissues.

The extracellular matrix (ECM) is commonly composed of ground substance, a gel-like fluid, fibrous components, and many structurally and functionally diverse molecules. These molecules include polysaccharides called glycosaminoglycans (GAGs). GAGs occupy most of the extracellular space and often take up a large volume relative to their mass. This results in a matrix that can withstand tremendous forces of compression. Most GAGs are linked to proteins—creating proteoglycans. These molecules retain sodium ions based on their positive charge and therefore attract water, which keeps the ECM hydrated. The ECM also contains rigid fibers such as collagens—the primary protein component of the ECM. Collagens are the most abundant proteins in animals, making up 25% of protein by mass. A large diversity of collagens with structural similarities provide tensile strength to many tissues. Notably, tissue like skin, blood vessels, and lungs need to be both strong and stretchy to perform their physiological role. A protein called elastin gives p

 Core: Cell Structure and Function

Quantitative Strain Mapping of an Abdominal Aortic Aneurysm

JoVE 10480

Source: 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


 Biomedical Engineering

An Introduction to the Chick: Gallus gallus domesticus

JoVE 5153

The chicken embryo (Gallus gallus domesticus) is an extremely valuable model organism for research in developmental biology, in part because most of their development takes place within an egg that is incubated outside of the mother. As a result, early developmental stages can be accessed, visualized and manipulated by simply creating a small hole in the eggshell. Since billions of…

 Biology II

Autocrine Signaling

JoVE 10973

Secreted signals can act on a variety of target cells. In some cases, the cell that secretes a signal also detects and responds to the signaling molecule it produces; this is called Autocrine Signaling.

Under normal physiological conditions, autocrine signaling is important for homeostasis. This process is well characterized in the macrophages of the immune system. Macrophages secrete a variety of signals including the cytokine Interleukin-1, IL-1. The secreting macrophages also possess membrane receptors for IL-1 that, when bound, can activate an intracellular signaling cascade. The resulting intracellular signals trigger the secretion of additional cytokines including more IL-1 from the target cell. Though IL-1 secreted by these macrophages can also bind to receptors on other cells and cell types, binding to the signaling cell is important in the regulation of signal production. Autocrine signaling is also a major mechanism of cancer cell proliferation. Cancerous cells secrete a variety of growth signals to themselves, through autocrine signaling, and to nearby tissues. For example, progesterone appears to act in an autocrine manner in breast cancer, whereby progesterone binds to progesterone receptors on the signaling cell, stimulating the action of growth-promoting genes. Autocrine signaling can also play a role in the development of skin cancer by stimulat

 Core: Cell Signaling

High-frequency Ultrasound Imaging of the Abdominal Aorta

JoVE 10397

Source: 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 …

 Biomedical Engineering

Physiology of the Circulatory System - Prep Student

JoVE 10569

Measuring Blood Pressure
To prepare for the blood pressure exercise, simply place the appropriate number of alcohol swabs, sphygmomanometers, and stethoscopes at the front of the classroom.
Be sure to check over each of the component parts of the sphygmomanometers, including the tubing, cuff, manometer, and bulb to ensure they are undamaged.…

 Lab Bio

Rodent Handling and Restraint Techniques

JoVE 10221

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


It has been demonstrated that even minimal handling of mice and rats is stressful to the animals. Handling for cage changing and other noninvasive procedures causes an increase in heart rate, blood pressure, and other physiological…

 Lab Animal Research

Tissues

JoVE 10696

Cells with similar structure and function are grouped into tissues. A group of tissues with a specialized function is called an organ. There are four main types of tissue in vertebrates: epithelial, connective, muscle, and nervous.

Epithelial tissue consists of thin sheets of cells and includes the skin and the linings of internal organs and body cavities. Epithelial cells are tightly packed, providing a barrier against injury, infection, and water loss. Epithelial tissue can be a single layer called simple epithelium, or multiple layers called stratified epithelium. In stratified epithelium, such as the skin, the outer cells—which are subject to damage—are replaced through the division of cells underneath. Epithelial cells have a variety of shapes, including squamous (flattened), cuboid, and columnar. Some epithelial tissues absorb or secrete substances, such as the lining of the intestines. Connective tissue is composed of cells within an extracellular matrix and includes loose connective tissue, fibrous connective tissue, adipose (fat) tissue, cartilage, bone, and blood. Although the characteristics of connective tissue vary greatly, their general function is to support and attach multiple tissues. For example, tendons are made of fibrous connective tissue and attach muscle to bone. Blood transports oxygen, nutrients and waste produ

 Core: Cell Structure and Function

Preparing and Administering Intramuscular Injections

JoVE 10261

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



Intramuscular (IM) injections deposit medications deep into the muscle tissue. Since muscle fibers are well perfused, this route of administration provides quick uptake of the medication and allows for the administration…

 Nursing Skills

Compound Administration I

JoVE 10198

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


As many research protocols require that a substance be injected into an animal, the route of delivery and the amount of the substance must be accurately determined. There are several routes of administration available in the mouse and rat. …

 Lab Animal Research

Diagnostic Necropsy and Tissue Harvest

JoVE 10294

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


Many animal experiments rely on final data collection time points that are gathered from the harvesting and testing of organs and tissues. The use of appropriate methods for the collection of organs and tissues can impact the quality of…

 Lab Animal Research

Compound Administration IV

JoVE 10214

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


There are many commonly used routes for compound administration in laboratory mice and rats. Protocols may, however, require the use of the less commonly used routes: intracardiac, footpad, and retro-orbital injections. Specialized…

 Lab Animal Research

Sterile Tissue Harvest

JoVE 10298

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


In 1959 The 3 R's were introduced by W.M.S. Russell and R.L. Burch in their book The Principles of Humane Experimental Technique. The 3 R's are replacement, reduction, and refinement of the use of animals in research.1 The …

 Lab Animal Research

Lateral Canthotomy and Inferior Cantholysis

JoVE 10266

Source: James W Bonz, MD, Emergency Medicine, Yale School of Medicine, New Haven, Connecticut, USA


Lateral canthotomy is a potentially eyesight-saving procedure when performed emergently for an orbital compartment syndrome. An orbital compartment syndrome results from a buildup of pressure behind the eye; as pressure mounts, both the optic …

 Emergency Medicine and Critical Care

Whole Organ Tissue Culture

JoVE 5799

Whole organs can be cultured ex vivo using specialized bioreactors, with the goal of repairing or replacing entire organs. This method uses a donor organ that is stripped of all cells, leaving behind the three-dimensional structure, and is then repopulated with new cells. This video demonstrates the whole organ culture of lungs, and shows how a dynamic culture…

 Bioengineering

Chick ex ovo Culture

JoVE 5157

One strength of the chicken (Gallus gallus domesticus) as a model organism for developmental biology is that the embryo develops outside the female and is easily accessible for experimental manipulation. Many techniques allow scientists to examine chicken embryos inside the eggshell (in ovo), but embryonic access can be limited at later stages of development.…

 Biology II

Compound Administration III

JoVE 10215

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


There are many commonly used routes for compound administration in laboratory mice and rats. However, certain protocols may require the use of less commonly used routes, including intradermal, intranasal, and intracranial injections.…

 Lab Animal Research

Development of the Chick

JoVE 5155

The chicken embryo (Gallus gallus domesticus) provides an economical and accessible model for developmental biology research. Chicks develop rapidly and are amenable to genetic and physiological manipulations, allowing researchers to investigate developmental pathways down to the cell and molecular levels.


This video review of chick development begins by describing the…

 Biology II

Peripheral Vascular Exam

JoVE 10122

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT


The prevalence of peripheral vascular disease (PVD) increases with age and is a significant cause of morbidity in older patients, and peripheral artery disease (PAD) is associated with cardiovascular and cerebrovascular complications.…

 Physical Examinations I

Sound Waves and Doppler Shift

JoVE 10411

Source: Arianna Brown, Asantha Cooray, PhD, Department of Physics & Astronomy, School of Physical Sciences, University of California, Irvine, CA


Waves are disturbances that propagate through a material medium or empty space. Light waves can travel through a vacuum and some forms of matter, and are transverse in nature, which means …

 Physics II

Piping Networks and Pressure Losses

JoVE 10389

Source: Alexander S Rattner, Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA


This experiment introduces the measurement and modeling of pressure losses in piping networks and internal flow systems. In such systems, frictional flow resistance from channel walls, fittings, and…

 Mechanical Engineering

Biodistribution of Nano-drug Carriers: Applications of SEM

JoVE 10472

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


Nanoparticles have been increasingly used research towards targeted drug delivery and controlled drug release. While most of these particles have been developed as polymeric…

 Biomedical Engineering

Overview of Tissue Engineering

JoVE 5785

Tissue engineering is an emerging field, which aims to create artificial tissue from biomaterials, specific cells and growth factors. These engineered tissue constructs have far-reaching benefits, with possibilities for organ replacement and tissue repair.


This video introduces the field of tissue engineering and examines the components …

 Bioengineering

Tissue Regeneration with Somatic Stem Cells

JoVE 5339

Somatic or adult stem cells, like embryonic stem cells, are capable of self-renewal but demonstrate a restricted differentiation potential. Nonetheless, these cells are crucial to homeostatic processes and play an important role in tissue repair. By studying and manipulating this cell population, scientist may be able to develop new regenerative therapies for injuries and diseases.


 Developmental Biology

Cancer

JoVE 10987

Cancers arise due to mutations in genes involved in the regulation of cell division, which leads to unrestricted cell proliferation. Modern science and medicine have made great strides in the understanding and treatment of cancer, including eradicating cancer in some patients. However, there is still no cure for cancer. This is largely due to the fact that cancer is a large group of many diseases. Tumors may result in a case where two people have the same mutations in an oncogene or tumor suppressor gene. Initially, the tumors may be very similar. However, the uncontrolled cell division results in new random mutations. As the tumor cells continue to divide, they become more varied. As a result, the two tumors will grow at different rates and undergo angiogenesis and metastasis at different times. The two cancers become so distinct from one another that they will not respond in the same way to the same therapy. This demonstrates why even a particular type of cancer, breast cancer, for example, can be a myriad of different cancers, each disease case with its unique properties, potentially requiring unique treatment approaches. As such, new cancer research and clinical trials focus on tailoring therapeutic approaches specifically for each patient’s genomic and molecular landscape. This is called personalized medicine. On the other hand, chemotherapy a

 Core: Cell Cycle and Division

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 …

 Developmental Biology

Basic Chick Care and Maintenance

JoVE 5154

Chicks (Gallus gallus domesticus) are a valuable research tool, not only for studying important concepts in vertebrate development, neuroscience, and tumor biology, but also as an efficient system in which to propagate viruses. Although eggs can be purchased from external suppliers and working with chicks requires very little specialized equipment, an understanding of proper handling…

 Biology II

Zebrafish Reproduction and Development

JoVE 5151

The zebrafish (Danio rerio) has become a popular model for studying genetics and developmental biology. The transparency of these animals at early developmental stages permits the direct visualization of tissue morphogenesis at the cellular level. Furthermore, zebrafish are amenable to genetic manipulation, allowing researchers to determine the effect of gene expression on the…

 Biology II

Isolation of Retinal Arterioles for Ex Vivo Cell Physiology Studies

1Centre for Experimental Medicine, Queen's University of Belfast, 2Centre for Biomedical Sciences (Education), Queen's University of Belfast, 3Department of Pharmaceutical Chemistry and Pharmacognosy, Naresuan University, 4School of Medicine, Dentistry and Biomedical Sciences, Queen's University of Belfast

JoVE 57944

 Biology
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