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General Hospital


Acute Respiratory Distress Syndrome [ARDS]
Life-threatening condition that develops when inflammation and injury to the lungs causes fluid buildup in the airways

Adhesion Molecule
Any of a large number of cell-surface molecules of several different classes that affect the attachment of one cell to another

A protein produced by the immune system in response to an antigen, often a virus or bacterium

The inflammation of a joint

Chronic condition causing difficulty breathing caused by over-reactive airways

One of many diseases in which fat builds up in the large- and medium-sized arteries, restricting blood flow

Autoimmune Disease
Disorder in which the immune system mistakenly attacks and destroys body tissue that it believes to be foreign

B Cell
A cell produced by the bone marrow that becomes either a memory cell or a plasma cell that forms antibodies against a foreign substance


Tiny, one-celled organism that reproduces by cell division and can be found in virtually any environment

Type of white blood cell that contains inflammatory mediators such as histamine

Disease caused by the abnormal and uncontrolled division of cells that invade and destroy surrounding body tissues

Molecule that causes white blood cells such as neutrophils and monocytes to move throughout the body (e.g., toward an injury) via the process of chemotaxis

Movement of a cell toward or away from a chemical substance

A fatty substance that higher organisms use in the construction of cell membranes and as an ingredient for making steroid molecules; it is carried through the bloodstream in molecules called lipoproteins

Compensatory Anti-Inflammatory Response Syndrome [CARS]
Condition that develops in some resuscitated injured patients when the body compensates in an effort to stop inflammation

Complement System
Set of molecules in the blood activated by the presence of bacteria, injury or other immune triggers, causing a range of responses associated with starting and maintaining inflammation

Abbreviation for the enzyme cyclooxygenase; the molecular target of nonsteroidal anti-inflammatory drugs (NSAIDs)

COX Inhibitor
Drug that blocks the action of the COX enzyme

C-Reactive Protein [CRP]
Protein not normally found at high levels in the blood of healthy people, but when present it indicates inflammation

Molecule that controls reactions among cells; key component of inflammation

Layer of skin just beneath the epidermis; it is composed of connective tissue and blood vessels

Swelling caused by the excessive accumulation of fluid in body tissues

Inflammation of the brain that is usually caused by infection by certain bacteria or viruses

Arising within the body or derived from the body

Poison in bacterial outer membranes that is harmful to the body, see lipopolysaccharide

Amoeba-like scavenger leukocyte (white blood cell) that disposes of cellular debris; often involved in allergic responses

Outer, "epithelial," layer of skin

A clinical condition characterized by recurrent attacks of seizures of sudden onset

Epithelial Cell

One of the closely packed cells in a thin layer that covers the internal and external surfaces of the body, including body cavities, ducts and vessels

Originating outside the body

Free Radical
An unstable molecule that reacts quickly with other atoms and molecules and can cause damage to living tissues

All the genetic material in the chromosomes of a particular organism

Granulocyte-macrophage colony-stimulating factor; a growth factor that stimulates the growth and division of precursors of granulocytes, monocytes, and macrophages

Molecule released especially during an allergic response that causes smooth muscle contraction, inflammation, mucus secretion, and other allergy symptoms

Bottom layer of skin, below the dermis

Immune system
The body's system for protection against infection and disease; involves immune cells, antibodies, and other molecules

Infection [bacterial, viral]
Invasion of the body by harmful microorganisms such as viruses, bacteria, fungi, or parasites

Infectious disease
Disease transmitted by microorganisms

The immediate, defensive reaction to any injury.

Inflammatory Mediator
Molecule inside or outside the body that plays a role in inflammation

A hormone produced in the pancreas that helps control levels of sugars, fats, and proteins in the body

Molecule (protein) produced by virally infected cells that helps the body fight off viral infections

One of a class of inflammatory mediators

White blood cell; acts as a part of the immune system by destroying invading cells and removing cellular debris

Leukotriene Inflammatory molecule thought to mediate the allergic response that causes lung constriction and muscle contraction in asthma

Poison in bacterial outer membranes that is harmful to the body; see endotoxin

Type of leukocyte (white blood cell) that mainly resides in lymphatic tissue (e.g., the lymph nodes) and is active in immune responses, including the production of antibodies; two types include B cells and T cells

Type of large leukocyte (white blood cell) that uses a process called phagocytosis to eat bacteria and digest cellular debris; during inflammation, develops the ability to produce inflammatory molecules

Mast cell
Type of leukocyte (white blood cell) found in connective tissues that produces histamine and other inflammatory molecules

Serious inflammatory condition resulting from bacterial or viral infection of the meninges, the wrapping that surrounds the brain and spinal cord

Type of leukocyte (white blood cell) that engulfs and breaks down debris and invading cells; can mature into a macrophage cell

Multiple Organ Dysfunction Syndrome[MODS]
Progressive failure of several interdependent organ systems that can be a consequence of the systemic inflammation following severe injury

Multiple Sclerosis
Autoimmune disease in which the body attacks its own nervous system, destroying the myelin sheath that protects nerve cells


A protein that covers and acts as an electrical insulator for nerve fibers

Nerve Disorders
Any of a variety of health disorders affecting the brain, spinal cord, and nervous system

A nerve cell; it receives and conducts electrical impulses from the brain; it consists of a cell body, an axon, axon terminals, and dendrites

Type of leukocyte (white blood cell) that travels through the blood to an injured site via a process called chemotaxis

Nitric Oxide
A highly reactive gas that is involved in a wide array of biological functions and functions as a part of the body's immune system

Non-Steroidal Anti-Inflammatory Drug [NSAID]
Any of a class of drugs that reduces pain, fever, or inflammation by interfering with the synthesis of prostaglandins

Microorganism that causes disease

Particle (pinched off from cell called a megakaryocyte) found in the bloodstream that initiates the blood clotting process

Any of a class of hormone-like molecules that participate in diverse body functions including inflammation; their production is blocked by NSAIDs

A large molecule encoded by a gene; they are required for the structure, function, and regulation of the body's cells, tissues, and organs; examples include hormones, enzymes, and antibodies

All the proteins made by a cell, organ, or organism at a particular time and under specific conditions

Process of reviving a patient from unconsciousness and restoring vital functions such as breathing

"Circulatory collapse," when blood pressure drops too low to maintain an adequate supply of blood to the body's tissues

Amplified, body-wide inflammatory response to traumatic injury, severe bleeding, or an infection caused by microorganisms like bacteria or fungi; typical symptoms include fever, mental confusion, a drop in blood pressure, and lung and kidney failure

Systemic Inflammation
Inflammation throughout the body

Systemic Inflammatory Response Syndrome [SIRS]
The syndrome of systemic inflammatory response to a major injury

T Cell
A type of cell produced by the thymus that plays a major role in immune reactions

Toll-Like Receptor [TLR]
Molecule on cell surfaces that helps the body sense the presence of endotoxin and other microbial products, and sends an alert to the immune system

Tumor Necrosis Factor [TNF]
Cytokine produced primarily by monocytes and macrophages

Trauma (Physical Trauma)
Wound or injury caused by a physical force; examples include the consequences of motor vehicle accidents, falls, drowning, gunshots, fires and burns, and stabbings

Vascular Cell Adhesion Molecule-1; One of a number of molecules on the surface of endothelial cells that controls cell adhesion and movement

Infectious agent composed of a protein coat around a DNA or RNA core; to reproduce, viruses depend on living cells

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