Inflammation Flashcards
Define it?
It is defence mechanism.
It is local change in living tissues when exposed to an injury not so severe to cause death of cell.
The reaction of living tissue to all forms of injury, & involves vascular, neurologic, humoral & cellular responses at the site of injury.
What is the principal features of acute inflammation?
Dilation and leaking of vessels, and involvement of circulating neutrophils.
Types of inflammation
Acute inf… : sudden onset, short duration, characterized by edema and neutrophiles, has severe systemic effect.
Chronic infla…: gradual onset, long duration, characterized by mononuclear cells and tissue destruction repair, has less severe systemic effect.
Name of Inflammation of pleura and lung?
Pleuristy and pneumonia.
Name of inflammation of:
- Togue
- stomach
- Testis
- Liver
- Kidney
- Glossitis
- gastristis
- orchitis
- hepatitis
- nephritis
Clinical significance of inflammation
Protective response:
Contain and isolate injury, destroy invading microorganisms, inactivate toxins, prepair tissue for healing and repair.
Inflammation may be harmful
Hypersensitivity ti a bee sting can cause anaphylactic shock and death.
Progressive organ damage (chronic inflammation and fibrosis) e.g RA
Causes of inflammation:
Same as cell injury: 1.Non living agent: A.physical: burn, trauma, radiation. B.chemical: toxins, caustic subs. 2.Living agent: A.(infective): microorganism 3.Immunological reaction
T or F
Chronic inflammation is the immediate and early response to injury.
F
Acute inflammation not chronic.
Cells that involve in acute inflammation:
Neutrophilis
Macrophages
Cardinal signs of acute inflammation:
Redness, heat, pain, swelling and loss of function.
Components of acute inflammation:
Vascular response
Neurological response: vasoconstriction
Cellular response
Humoral response (Chemical mediators)
Vascular changes in acute infla..:
Initial inconstant vasoconstriction then VASODILATATION that leads to increase blood VOLUME and FLOW
increase PERMEABILITY and VISCOSITY and STASIS
Margination of PMN is a feature of:
Acute inflammation
How to Increase vascular permeability in acute infla..
Endothelial contraction, retraction, direct injury and leukocyte dependent endothelial injury.
T or F
Retraction of endothelial cells occurs mainly in venules and induced by histamine, NO and other mediators.
True
T or F
Retraction of endothelial cells occurs mainly in arterioles and induced by histamine, NO and other mediators.
F
It occures mainly in venules.
Endothelial injury occures in arterioles, capillaries and venules and caused by:
Burns, some microbial toxins
Leukocyte mediated vascular injury occures mainly in:
Pulmonary capillaries
And associated with late stage of inflammation
Increased transcytosis in acute infla… occurs in:
Occurs in venules and induced by vascular endothelial growth factor (VEGF).
Cellular phase in acute inflammation:
Margination, Adhesion Diapedesis and chemotaxis
Main differences b/w Exudate and Transudate:
T:clear, protein poor fluid, and It appears at an early stage of the inflammation and hypoalbumnemia
E:cloudy, protein rich fluid and Neutrophils and It appears at a later stage of the inflammation
T or F
PMNs are predominant cells in acute inflammation.
T
Sequence of leukocyte response in acute inlfammation:
- Margination, rolling and adhesion
- Emigration and chemotaxis
- Phagocytosis, degranulation and killing
How leukocyte kills microoganisms in acute infla…
- Recognition and attachment
- engulfment and phagocytic vacuole formation
- Degranulation and killig
Define the chemical mediators and give some examples
They are chemicals released during acute inflammation and are responsible for all inflammatory processes.
Eg: vasoactive amines like histamine and serotin
Binding of adhesion molecules on WBC and endothelial cell modulated by:
chemical mediators
T or F
In the bacterial infection, PMN first emigrate then replaced by monocytes.
T
T or F
In the tubercle or typhoid infections monocytes emigrate from beginning.
T
In the viral imfection and immune reactions, lymphocytes emigrate from the beginning
T
In hypersensitivity reactions, eosinophils predominante.
T
Endothelial adhesion receptors:
Selectin,(E,P,L), immunoglobulin family molecule (ICAM1, VCAM1), WBC receptors, integrins (CD1 1/18, VLA0R), mucin like glycoproteins
Migration of PMN across endothelium (transmigration) is mediated by :
CD31
What is the chemotaxis?
Unidirectional movement of leukocytes towards the site of injury, mediated by diffusible chemical attractants.
Chemotactic factors for Neutrophils:
C5a, leukotrine B4, Bacterial products
Chemotactic factors for monocyte-Macrophages:
C5a C3a, leukotriene B4, Bacterial products
Chemotactic factors of Eosinophils:
Eosinophil chemotactic factor of anaphylaxis
PG D2
Histamine
Cells undergooing extravasation
Neutrophils : during 6-24h, more abundant, short lived, respond more rapidly
Monocytes: after 24-48h, Survive longer, come to end acute inflammation, (if they persist –》 chronic inflammation)
Definition of phagocytosis
Is a process by which neutrophils and macrophages engulf the offending pathogen.
It is the major benefit of leukocyte accumulation
Mechanism of attachment of pathogen on leukocytes
The pathogen is coated by opsonins.
Fc fragment of Ig to Fc receptor on leukocytes
And complement fragment C3b to C3b receptor
Phagocytosis steps:
Recognition and attachment
Engulfment
Killing and degradation
Engulfement mechanism
By pseudopods which encircle the pathogen creating a phagosome.
Pathogen killing and degradation:
2 mechanisms:
O2 dependent and independent
O2 dependent mechanism:
The most important:
Activation of NADPH oxidase 》conversion of O2 to reactive species with the help of lysosomal myeloperxidase (MPO)》Powerful bactericidal agents (bleach)