Week 4 Flashcards
Define chemical mediators
a variety of chemicals secreted by various cells and from injured tissue involved in the inflammatory response e.g., histamine
Define chemotaxis
phenomenon that guides and attracts WBCs to the site of injury. Chemotactic agents include some of the chemical mediators, antibodies, products from bacteria and dead tissue
Define cicatrix
a scar; the fibrous tissue left after the healing of a wound
Define cicatrization
the formation of a scar (by conversion of granulation tissue to a scar)
Define collagen
the protein substance of fibers of skin, tendon, bone, cartilage, and other connective tissues; produced by fibroblasts; several different types
Define exudate
fluid accumulation outside of a vessel; it has a high protein content and contains various types of inflammatory cells
Define fibrosis
formation of fibrous tissue usually in repair or replacement of cellular elements
Define granulation tissue
small, rounded masses of tissue formed during healing; made up of newly formed capillaries, fibroblasts elaborating connective tissue, and macrophages
Define hyperemia
excess of blood in a part
Define keloid
a sharply elevated, irregularly shaped scar due to excessive collagen formation during connective tissue repair
Define leukocyte
white blood cell (WBC)
Define leukocytosis
a transient increase in the number of leukocytes (WBCs) in the blood
Define monocyte/macrophage
type of white blood cell; as inflammatory process continues these cells finish off what the neutrophils begin and continue to clean up the debris
Define permeability
the degree of selectivity a membrane shows in allowing substances to pass through or in preventing passage; “leakiness”
Define phagocytosis
a process in which a cell takes particles and substances into itself for destruction
Define pus
a thick, opaque, usually yellowish-white, fluid matter that is formed as part of an inflammatory response containing dead white blood cells (such as neutrophils)
Define pyogen
a pus-producing microorganism
Define pyrogen
a fever-producing microorganism
Describe inflammation
a host response to cellular/tissue damage and infection. It is a protective response that is essential for our survival
What are the purposes of an inflammatory reaction?
1.Destroy or limit the spread of the injurious agent
2.Allow for repair or replacement of the damaged tissue
What are the major players in the inflammatory response?
Blood vessels and leukocytes (WBCs)
What steps do the inflammatory response consist of?
1.Recognition – an offending agent is recognized by host cells and molecules
2.Recruitment – Leukocytes and plasma proteins are recruited from the circulation
3.Removal – Agent is destroyed and eliminated by activated leukocytes and proteins
4.Regulation – The reaction is controlled and terminated
5.Resolution – The damaged tissue is repaired
What are the 5 principles of inflammation?
1.Inflammation is a dynamic process that starts with the injury and culminates with healing or repair
2.It is primarily a protective response, but it may be potentially harmful
3.The inflammatory reaction is non-specific: i.e., a stereotyped process regardless of the nature of the injury
4.The intensity, duration, and outcome of the inflammatory reaction are modified by a variety of host factors and factors related to the injurious insult or etiologic agent
5.For inflammation to occur, the injury must be non-lethal
