Mdti - Cell Injury 03

Front 1

Where is histamine found?

What is is released by?

What does it cause?

Back 1

Found in mast cells, basophils, platelets

Released by:
- Trauma, Heat
- IgE binding to mast cell Fc Receptores
- Anaphylatoxins C3a/C5a

Histamine causes arteriolar vasodilation and venular endothelial contraction

Front 2

What are 4 important classes of chemical mediators?

Back 2

1. Histamine

2. Prostaglandins/Leukotrienes

3. Cytokines: IL 1 / TNF

4. Nitric Oxide

Front 3

TNF, IL-1, and IFG are all types of what?

Back 3

Cytokines

Front 4

What is the role of IFG?

Back 4

Activation of macrophages

Front 5

What is the role of TNF and IL-1?

Back 5

- Produced by activated macrophage

- Induction of systemic acute phase reactions (fever, anorexia, etc)

- Mediates hypotension in septic shock (TNF)

- Aggregation and activation of neutrophils, proteolytic enzyme release, and tissue damage

Front 6

What is Nitric Oxide produced by?

What are its actions?

Back 6

NO produced by macrophages and endothelial cells in inflammatory states

- Relaxes smooth muscle (vasodilator)

- antagonizes platelet activation

- Is a microcidal agent in activated macrophages, can also damage tissue

Front 7

What do neutral proteases do?

Back 7

- Contained in lysosomal granules

- Enzymes (elastase, collagenase) destroy bacteria

- a1-antitrypsin NEUTRALIZES these to ensure leakage doesn't cause tissue damage

Front 8

What cell types are seen in chronic inflammation?

Acute?

Back 8

Chronic: Macrophages, LYMPHOCYTES, plasma cells (Mononuclear cells)

Acute: NEUTROPHILS

Front 9

Are acute and chronic inflammation defined by time?

Back 9

NO, used by pathologists to describe microscopic features

Front 10

Does healing and ongoing tissue injury occur simultaneously in chronic inflammation?

Back 10

Yes

Front 11

What often initiates an acute infection?

Chronic?

Back 11

Acute:
- Microbial surfaces and fragments.
- Damaged and fragmented tissue

Chronic:
- Non-Digestible organisms (many viral infections)
- Non-degradable foreign matter
- Auto-immune reactions

Front 12

What are the outcomes for an acute infection?

Chronic?

Back 12

Acute:
- Resolution, abscess formation
- Tissue destruction, Chronic inflammation

Chronic:
- Tissue Destruction, Fibrosis

Front 13

Where are immune cells usually located in a viral pneumonia?

Back 13

Viral: Tend to have an interstitial infiltrate, with the inflammatory cells localized within the walls of the alveoli, not in the alveolar spaces

Front 14

What is the most prevalent chronic occupational disease in the world?

Back 14

Silicosis

Front 15

What are plasma cells?

What do they look like?

Back 15

Plasma Cells: terminally differentiated B cells (produce Ig)

Characterized by eccentric nucleus, which has peculiar clumped chromatin that looks like a "clock face"

Front 16

What are the functions of eosinophils?

Back 16

- Characteristic of immune response to parasites, contain Major Basic Protein which is toxic to worms

- immune reactions

- Look very pink

- Part of CHRONIC INFLAMMATION

Front 17

What is the function of mast cells?

Back 17

Sentinel cells that can participate in both acute and chronic inflammatory responses

- Release histamine and arachidonic acid

Front 18

What is granulomatous inflammation?

Back 18

- subtype of chronic inflammation

- contains a granuloma

- characterized by aggregates of "epitheliod cells" which are activated macrophages that assume a squamous like appearance

- Often see Multinucelated giant cells

Front 19

What is an epithelioid cell?

In what type of inflammation is it observed?

Back 19

A macrophage seen in granulomatous inflammation that has assumed an appearance which is similar to an epithelial cell

Front 20

Why do granulomas form?

Back 20

Because of a persistent T cell response to intracellular, poorly digestible microbes

Sometimes a response to inert foreign bodies

Front 21

What are langhans giants cell?

What are foreign body type cells?

Back 21

Langans Giant Cell: Nuclei have a wreath-like arrangement

Foreign Body type giant cells: Have haphazardly arranged nuclei

Front 22

What are 4 bacterial causes of granulomatous inflammation?

Back 22

1. TB
2. Leprosy
3. Syphilis
4. Cat-scratch disease

Front 23

What are 4 Systemic Effect of inflammatory states (acute phase reaction)?

Back 23

1. Fever

2. Leukocytosis (increase WBC's)

3. Somnolence, malaise, anorexia, hypotension

4. Acute phase proteins

Represent reactions to CYTOKINES produces by inflammatory cells or bacterial products

Front 24

What are the biological substances that initiate a fever?

What are their two types?

Back 24

Pyrogens

1. Exogenous pyrogens: pyrogens produces by a microorganism

2. Endogenous pyrogens: produced by the body as part of the inflammatory response (ex: IL-1 and TNF)

Front 25

What cell type is seen in a bacterial infection?

Parasitic?

Viral?

Back 25

Bacterial: Neutrophilia

Parasitic: Eosinophilia

Viral: Lymphocytosis

Front 26

What are acute phase proteins?

Back 26

Plasma proteins, most synthesized in the liver, whose synthesis increases several hundred fold in response to inflammatory stimuli (ex: fibrinogen and C-reactive protein)

Front 27

What is an ESR?

Back 27

Erythrocyte Sedimentation Rate Test

Measurment of the distance that RBC's fall in a vertical column of anti-coagulated blood

- The more acute phase proteins = the faster the fall