SSS FunMed2 Flashcards
After activation, which type of immunity do CD4 Th1 cells and CD4 Th2 cells trigger? [2]
which cytokines causes this to happen for each?
- CD4+ Th1 Cell: IFN-y & TNFa: - triggers cell mediated immunity (to target intracellular pathogens, using CD8+, NK & macrophages)
- CD4+ Th2 Cell: IL-4, IL5, IL-13: triggers humoral immunity (extracellular pathogens - B cells & lots of proteins)
what do both MHC Class I & Class II have on them? [1]
Both have peptide-binding cleft: but the fit between the amino acid side chains inthe peptide and the grove of MHC molecule determine binding
what is Th1 vs Th2 response to allergies?
- Th2 responses lead to IL-4, which leads to IgE, which causes allergies
how do cytokines drive the recruitment of immune cells (when endothelium is damaged)? (3)
what do TNFa and chemokines do specifically?
- *1. tethering:** cytokines make the lining the BV more sticky
- *2. rolling and activation:** chemokines activated adhesion molecules and allow rolling arrest
- *3 diapedesis & migraton:** cause cells to flow in to cells within tissues
- *TNFa**: increaes stickiness of endothelium by increasing expression of adhesion molecules:
- rapid release from Weibal-Palade bodies (WP) (adhesion molecules)
- new synthesis of TNF molecules
- *Chemokines**: activate adhesion molecules to increase binding
- causes rearangement of adhesion molecules on surface of cell, to bind more strongly to vessel wall.
how does a cyotkine storm occur?
cytokine production becomes uncontrolled to a potentially fatal positive feedback loop:
- *- cytokine stimulates immune cell
- immune cell produces cytokine**
what is difference between immune reponse in normal v asthma / allergy ?
normal:
- niave CD4+ T cell in presence of IL-4 = Th2 cell
- Th2 cell produces more IL-4, which induces B cell to class swich to make IgE
- IgE binds to mast cells, which, if comes into contact with antigen that induced B cells, causes degranulation
asthma:
- overproduction of IL-4 -> drives allergies and asthma
- its the release of the degranulation by mast cells that causes response
- if have an allergy: subsequent exposure are rapidly released (why get really quick response)
what granules do basophils contain? [2]
Large dark purple cytoplasmic granules that often obscure the bilobed nucleus
The granules contain:
Histamine (vasoactive substance which promotes vasodilation during inflammation)
Heparin (an anticoagulant which prevents clotting
Q
acid / base disorders:
If the problem is with the respiratory system, the kidneys can compensate by altering HCO3-. How is this altered for acidosis & alkalsosi?
A
If the problem is with the respiratory system, kidneys:
- In acidosis: increases HCO3-
- In alkalosis: ¯ HCO3-
innate immunity tries to take out pathogens. the system uses complement blood proteins. name 2 that do this and their role [2]
Uses complement blood proteins that
- opsonise (act as markers for phagocytes)
- cytolyse (directly attack via membrane attack complex (MAC))
- enhance inflammation
Q
acid / base disorders:
If the problem is metabolic, the lungs can compensate by altering Co2 levels. How is this altered for acidosis & alkalsosi?
•the lungs can compensate by altering CO2 Levels
•In acidosis: increases RR (decreases CO2)
•In alkalosis: decreaeses¯ RR (increases CO2)
which nuclei in the hypothalamus recieve information regarding:
a) warm temperatures [1]
b) cold temperatures [2]
- preoptic area (POA) monitors core temperature: recieves input from warm receptors from skin and and internal receptors
- paraventricular (PVN) and dorsomedial hypothalamic (DMH) nuclei: recieve input from cold
what are the products of Krebs cycle? [4]
- produces: Co2, 3NADH, 1 FADH2, 1GTP. feeds into oxidative phosphorylation pathway
label A-D stages of cancer development:
A
B
C
D
label A-D stages of cancer development:
A: hyperplasia
B: metaplasia
C: dysplasia
D: anaplasia
what can type 2,3, & 4 hypersensitivty be
Type II: IgG/IgM to patients own RBCs due to M. pneumonia
Type III: complement activation causing inflammation e.g. S. pyogenes causing glomerulonephritis
Type IV: T cell mediated e.g. TB granulomas
1-4: ACID
what are the spectrums for antiobiotics? (2)
Broad: both aerobes and anaerobes
Narrow: either aerobes or anaerobes or a specific gram +/-
name two ways that cancer can be caused by mutations to transcription factors [2]
C-MYC overexpression: breast / colon cancer
C-MYC translocation: burkitt lymphoma
what are the two types of venules?
how do u distinguish them?
- Postcapillary venules collect blood from the capillary network and are characterized of pericytes (contractible cells wrapped around the endothelial cells). Made up of endothelial, basal lamina and pericytes.
- Muscular venules can be distinguished by the presence of tunica media. Distal to the postcapillary venules and have one to two SMC layers.
(picture on right = postcapil, on left; muscular venules)
** which method of calculating HR do you use if the ECG is irregular? **
A
QRS X 6
what does the phrenic nerve cause during inhalation / exhalation? [2]
The motor innervation activation will cause the diaphragm to contract with inspiration, resulting in a flattened diaphragm and increased intrapleural space.
During exhalation, the diaphragm relaxes and returns to the dual dome shape.
The phrenic nerve also provides touch and pain sensory innervation to the mediastinal pleura and the pericardium in addition to the intercostal nerves.
trachea runs from where to where?
at which structures in trachea does the aorta cross over?
levels of oesphagus? [1]
trachea: c6-t4
- aorta arches over left main bronchus and lung root
- C6-T10 = oesphagus