Weekend LObs Flashcards
Why does Fetal Hemoglobin bind more strongly to O2 than Adult Hemoglobin?
2,3-BPG - which enhances hemoglobin’s ability to release oxygen - interacts much more with hemoglobin A than hemoglobin F.
This is because the adult β subunit has more positive charges than the fetal γ subunit, which attract the negative charges from 2,3-BPG.
Due to the preference of 2,3-BPG for hemoglobin A, hemoglobin F binds to oxygen with more affinity, in average.
Give a precise definition of a Genetic disease:
A disease caused by an abnormality in an individual’s genome.
Draw a diagram of the spleen, and label its vasculature, white and red pulp.
Describe the makeup of each element of the White Pulp
Periarteriolar Lymphatic Sheath:
Contains mainly T cells and Macrophages
Marginal Zone:
Contains mainly Macrophages
Follicles:
Contain B-cells, they are situated withing the Marginal Zone
How do the end capillaries within the spleen connect with the venous system?
The walls of the end capillaries are highly permeable, blood cells pass freely through and enter the CORDS OF BILLROTH.
The cords of billroth are full of macrophages, and those cells that succesfully pass through are recovered by the venous sinous system
Finally the venous sinus empties into the collecting vein, and then into the splenic vein.
Draw a diagram outlining the cords of billroth
Why does SCA often result in Splenic Sequestration?
These RBCs, now sickled, are unable to pass through the small endothelial slits of the venous sinuses and rejoin the intravascular system
Define an opsonin
Opsonins are extracellular proteins that, when bound to substances or cells, induce phagocytes to phagocytose the substances or cells with the opsonins bound
Define and describe opsonization
Opsonization is an immune process which uses opsonins to tag foreign pathogens for elimination by phagocytes.
Without an opsonin, such as an antibody, the negatively-charged cell walls of the pathogen and phagocyte repel each other.
What is the membrane attack complex?
The membrane attack complex is a complex of proteins typically formed on the surface of pathogen cell membranes
Assembly of the MAC leads to pores that disrupt the cell membrane of target cells, leading to cell lysis and death.[2]
What is Immunoglobin G?
Immunoglobulin G is a type of antibody.
Representing approximately 75% of serum antibodies in humans, IgG is the most common type of antibody found in blood circulation.
IgG molecules are created and released by plasma B cells.
Explain why patients without a spleen are more susceptible to encapsulated bacteria infections?
- The spleen is a excellent site for phagocytosis
Loss of Marginal Zone B-cells leads to reduced production of Immunoglobulin G antibodies
- Results in decreased opsonizing ability
- Decreased production of Properdin, which is essential for the alternative complement pathway.
- Thus the function of the Membrane Attack Complex is inhibited
Draw a diagram of each of the three complement pathways and their corresponding proteins.
Each of the three complement pathways essentially perform the same function of activating which protein?
And what does that lead to?
C3 Protein
C3a - Enhances Inflammation
C3b - Initiates Opsonization + the Membrane Attack Complex
What is antibiotic prophylaxis?
When physicians suggest taking antibiotics before treatment to decrease the chance of infection.
Name 7 types of encapsulated bacteria - using the SHiNE SKiS mnemonic
What are the three preventative measures than can be taken to reduce the risk of SCD sufferers contracting serious bacteria-related comorbidities?
What tests can confirm SCA?
And what results would we expect from them?
Outline the short and long term strategies for living with and managing SCD.
What is thallassemia?
What are the consequences of B-Thallasemia major?
