6.6 Blood 2 Flashcards
What is neutrophilia?
high levels of neutrophils caused by infection, inflammation, malignancy
What is neutropenia? Causes?
low levels of neutrophils in the blood due to a shift into tissues during infection
What is eosinophilia?
high eosinophils due to allergy or parasitic infection
What are the chemical mediators released by damaged tissue that stimulate WBC production?
Interleukins (IL)
CSF- colony stimulating factors
What are leukemia and lymphoma?
leukemia: blood malignancy
abnormal, continued proliferation of bone marrow precursor “blast” cells, do not differentiate into mature cells
lymphoma: lymph node malignancy
abnormal proliferation of B and T-lymphocytes in the lymph nodes or other lymphatic tissue
What cell type creates platelets?
Megakaryocytes
What are the characteristics of a platelet cell?
Have some organelles- actin + myosin = can contract
Also clothing chemicals
What hormone stimulates platelet production? Where are platelets broken down?
Thrombopoeitin- liver hormone stimulates megakaryocytic activity in marrow
Broken down by macrophages in spleen and liver
What is hemostasis? What 3 steps occur?
Cascade of steps to stop bleeding
1-vascular spasm
2- platelet plug formation
3- coagulation
What happens in vascular spasm?
injury to vessel releases chemicals
smooth muscle in blood vessel wall contracts
20-30 minutes, reduces blood flow to area, most effective in small vessels
How does the platelet plug form? What kind of feedback is this?
vonWillebrand Factor binds platelets to collagen in the blood vessel wall
platelets swell, become spiky and release chemicals that cause more platelet aggregation:
platelet plug is formed within 1 minute
+ feedback
What happens during coagulation?
platelet plug is reinforced by fibrin mesh, forming a clot
Complex process that requires a cascade of molecules
Needs to be tightly regulated to prevent abnormal clot formation which can block blood vessels (heart attack, stroke, tissue damage)
What is the intrinsic clotting pathway? Which clotting factors are involved?
stimulated by endothelium damage, ex: arteriosclerosis
starts with clotting Factor XII –> X
What is the extrinsic clotting pathway? Which clotting factors are involved?
stimulated by external injury to blood vessel, ex: laceration
starts with clotting Factor VII–>X
Once clotting factor X is activated, what happens next?
Factor X – leads to conversion of prothrombin to thrombin
Thrombin converts fibrinogen into the fibrin mesh
How do clots retract and heal?
clot retraction: actin and myosin in platelets contract, compacts the clot, draws injured vessel together (30-60 minutes)
platelet derived growth factor (PDGF): stimulates regrowth of the blood vessel
clot fibrinolysis: enzymes digest fibrin after vessel is healed (2+ days), clot is dissolved and healing can continue
plasmin
plasminogen
tissue plasminogen activator
What is thrombocytosis? Common causes?
excessive platelets
post-splenectomy (loss of breakdown), bone marrow activation, cancer, inflammation
What are some causes of platelet dysfunction?
antiplatelet therapy, aspirin, NSAIDs, high nitrogenous waste levels during renal failure
What are some common causes of decreased coagulation?
caused by: clotting factor deficiency, inherited hemophilia, von Willebrand disease liver disease (cirrhosis)- decreases synthesis Vitamin K deficiency - required for coagulation factor function
What is the difference between antigen and antibodies on RBCs?
Antibodies are proteins that are present in the plasma and can mount an immune response to foreign cells. RBC’s are identified as self or foreign based on the antigen molecules they carry on their surface.
What type of antigen and antibodies are found on type B blood?
anti-A antibodies
B-antigen
What type of antigen and antibodies are found on type B blood?
anti-A antibodies
B-antigen
What type of antibodies and antigen are found on AB blood?
No antibodies
A-antigen; B-antigen
= universal recipient
What type of antibodies and antigen are found on O blood?
anti-A antibodies
anti-B antibodies
No antigens
= Universal donor
