many parts of the chapter that we covered in immunology is cut out!!
when does acute inflammation occur and for how long?
develops within minutes or hours lasting for several hours or a few days.
the majority of cellular infiltrate during acute inflammation is...
neutrophils
local and systemic signs are more prominent in acute or chronic inflammation?
acute
the majority of cellular infiltrate during chronic inflammation is...
monocytes and lymphocytes
what cells are involved in acute respiratory distress syndrome
neutrophils
what cells and antibodies are involved the most in Asthma?
eosinophils and IgE antibodies
what cells and molecules are involved the most in Glomerulonephritis?
complement system, neutrophils, and monocytes
what is most involved during Septic shock?
cytokines
examples of diseases caused by acute inflammation
acute respiratory distress syndrome, asthma, glomerulonephritis, and septic shock
examples of diseases caused by chronic inflammation
arthritis, asthma, atherosclerosis, and pulmonary fibrosis
causes of inflammation
infections, tissue necrosis, foreign bodies such as splinters, immune reactions such as allergies
5 steps of the inflammatory response
(1) recognition of the injurious agent (2) recruitment of leukocytes (3) removal of the agent (4) regulation (control) of the response (5) resolution (repair).
what is the exudate state of blood vessels?
increased interendothelial space and vasodilation due to inflammation, leading to protein and leukocyte leakage
what is the transudate state of blood vessels?
increased colloid osmotic pressure, decreased protein synthesis, increased protein loss, protein malnutrition, increased fluid leakage
what is erythema?
redness at the site of inflammation
when the permeability of the microvasculature increases, the outpouring fluid is rich in...
protein
the loss of fluid and increase in vessel diameter leads to...
slower blood flow, increased viscosity of blood, increased concentration of red blood cells in smaller vessels. (vascular congestion)
3 mechanisms responsible for increased vascular permeability
Retraction of endothelial cells (gaps in the vessels) elicited by histamine, bradykinin, leukotrienes, and other chemical mediators. endothelial injury Increased transport of fluids and proteins (transcytosis)
differentiate between lymphangitis and lymphadenitis
lymphangitis: inflammation of lymphatic duct lymphadenitis: inflammation and enlargement of lymph node. both can be a result of secondary inflammation
Neutrophils and macrophages both originate as...
HSCs in the bone marrow
life span of neutrophils in tissues
1-2 days
life span of inflammatory macrophages
days-weeks
life span of tissue-resident macrophages
years
which cell responds more rapidly to stimuli, neutrophils or macrophages?
neutrophils
which cell can have high levels of nitrous oxide, neutrophils or macrophages?
macrophage
what induces the degranulation of neutrophils?
cytoskeletal rearrangement
which cell produces more cytokines, neutrophils or macrophages?
macrophage
examples of chemoattractants
Bacterial products, Cytokines, complement proteins (particularly C5a), Products of arachidonic acid metabolism
leukocytes rolling on the endothelium is mediated by...
selectins
the firm attachment of leukocytes to the endothelium is mediated by...
integrins
3 steps to phagocytosis
(1) recognition and attachment of the particle to be ingested by the leukocyte engulfment, with subsequent formation of a phagocytic vacuole killing or degradation of the ingested material
NETs are often detected in the blood when a patient has...
sepsis
what is responsible for terminating the inflammatory response?
anti-inflammatory mediators (TGF-beta and IL10)
kinins are produced in...
liver
complement proteins are produced in...
liver
what are the arachidonic acid metabolites?
prostaglandins and leukotrienes
example of vasoactive amine and its function
histamine; vasodilation and increased vascular permeability
examples of arachinodic acid metabolites and its function
prostaglandins and leukotrienes; vascular reactions, leukocyte chemotaxis, and other reactions of inflammation
arachidonic acid metabolites are antagonized by...
lipoxins
function of cytokines
leukocyte recruitment and migration
function of complement proteins
generation of multiple breakdown products responsible for leukocyte chemotaxis, opsonization, phagocytosis, cell killing
function of kinins
mediate vascular reaction and activate nociceptors
causes of chronic inflammation
persistent infections, hypersensitivity diseases, prolonged exposure to potentially toxic agents
resident tissue macrophages are made in....
the the fetal liver (yolk sak)
M1 macrophages are activated by...
microbial products such as endotoxin and TNF-gamma
function of M1 macrophages
produce NO and ROS and upregulate lysosomal enzymes which enhance their ability to kill ingested organisms secrete cytokines that stimulate inflammation. in host defense against microbes and in many inflammatory reactions.
M2 macrophages are activated by...
IL-4 and IL-13
function of M2 macrophages
tissue repair (They secrete growth factors that promote angiogenesis, activate fibroblasts, and stimulate collagen synthesis.)
besides M1 macrophages and neutrophils, what cell enhances and amplifies inflammation?
CD4+ t cells
what do the granules in the eosinophil contain that is toxic to parasites?
major basic protein
mast cells are very similar to what cell?
basophil
granulomatous inflammation is what type of hypersensitivity?
type 4
tissue reaction of tuberculosis
caused by Mycobacterium tuberculosis Caseating granuloma central necrosis with amorphous granular debris; acid-fast bacilli
tissue reaction of leprosy
Acid-fast bacilli in macrophages; noncaseating granulomas
tissue reaction of syphillis
Gumma: microscopic to grossly visible lesion, enclosing wall of macrophages; plasma cell infiltrate; central cells are necrotic without loss of cellular outline; organisms difficult to identify in tissue
tissue reaction of cat-scratch disease
Rounded or stellate granuloma containing central granular debris and recognizable neutrophils; giant cells uncommon
tissue reaction of sarcoidosis
cause is unknown. Noncaseating granulomas with abundant activated macrophages
tissue reaction of crohn's disease
Occasional noncaseating granulomas in the wall of the intestine, with dense chronic inflammatory infiltrate
severe bacterial infections are called
sepsis
clinical/pathological changes in the body as a result of acute-phase response
fever, elevated levels of c-reactive protein, leukocytosis (increased heart rate and blood pressure)
the clinical triad of septic shock
intravascular coagulation, hypotensive shock, and metabolic disturbances including insulin resistance and hyperglycemia.
differentiate between regeneration and scar formation
regeneration: when tissues are able to return to its normal state, and when cell types that can proliferate quickly survive the injury (i.e. epithelial cells)
scar formation: connective tissue deposition when injured tissues are not capable of returning to its original state.
what is fibrosis?
extensive deposition of collagen that occurs in the lungs, liver, kidney, and other organs as a consequence of chronic inflammation, or in the myocardium after extensive ischemic necrosis (infarction).
If fibrosis develops in a tissue space occupied by an inflammatory exudate, it is called....
organization
examples of continuously dividing cells
epithelial cells and hematopoietic cells
examples of nondividing cells
neurons, skeletal and cardiac muscle
liver regeneration is triggered by...
cytokines and growth factors
3 steps of scar formation
inflammation, cell proliferation, remodeling.
what cells are the central cellular players in the repair process?
macrophages (M1 clears necrotic tissue, M2 produces growth factors)
what is angiogenesis?
the process when endothelial and other vascular cells proliferate to form new blood vessels
outline the process of angiogenesis
Vasodilation in response to NO and increased permeability induced by VEGF breakdown of the basement membrane Migration of endothelial cells toward the area of tissue injury Proliferation of endothelial cells behind the tip of migrating cells Remodeling into capillary tubes formation of the mature vessel Suppression of proliferation deposition of the basement membrane
what growth factor stimulates migration and proliferation of endothelial cells?
VEGF-A, FGF-2, PDGF, TGF-beta
what is notch signaling?
regulates the sprouting and branching of new vessels and thus ensures that the new vessels that are formed have the proper spacing to effectively supply the healing tissue with blood.
factors that impair tissue repair
infection, diabetes, nutritional status, steroids, location of injury (when the exudate is too large to be fully resorbed it undergoes organization, a process during which granulation tissue grows into the exudate, and a fibrous scar ultimately forms)
what are venous leg ulcers?
develop in elderly people as a result of chronic venous hypertension, which may be caused by severe varicose veins or congestive heart failure. Deposits of hemosiderin resulting from red cell breakdown, chronic inflammation. These ulcers fail to heal because of poor delivery of oxygen to the site of the ulcer
what are Arterial ulcers?
develop in individuals with atherosclerosis of peripheral arteries associated with diabetes. The ischemia results in atrophy and necrosis of the skin and underlying tissues.
what are Pressure sores?
areas of skin ulceration and necrosis of underlying tissues caused by prolonged compression of tissues against a bone, for example, in bedridden, immobile elderly individuals with numerous morbidities. The lesions are caused by mechanical pressure and local ischemia.
what are diabetic ulcers?
affect lower extremities, particularly feet. Tissue necrosis and failure to heal are the result of small vessel disease causing ischemia, neuropathy, systemic metabolic abnormalities, and secondary infections. characterized by epithelial ulceration and extensive granulation tissue in the underlying dermis
In some cases such as post-operation, failure of healing and changes in abdominal pressure may lead to wound rupture. this is called...
dehiscence
what is a hypertrophic scar?
accumulation of excessive amounts of collagen resulting in a raised scar
what is a keloid?
scar tissue growing beyond the boundaries of the original wound and not regressing