Course summary

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III- Haemolisys Erytrhopoietin : make red blood cells Haemolisys : pysiological process. Occurs in spleen (+liver, reed bone narrow) by macrophages that eliminate older red blood cells slow continuous haemolytic state always present (1-2% of erythrocytes, [Hbfree] close to 0.1 mg/dl) <!> Beyond the process is pathological → anaemia of varying severity - release of haemoglobin into plasma → toxic state if [Hbfree] > 160 mg/dl) → red urine. - torn stroma → can clog filters (liver, spleen and kidneys) spectrophotometer: determine amount of aemolysis Fluid mosaic model: Cell membrane = lipid bilayer + proteins immersed (significant degree of mobility) Lipid layer = double leaflet -> phospholipids: hydrophobic tails face inward hydrophilic tails face outward Hydrophobic -> adhesion cellule ➔ causes of blood damage (haemolysis): - mechanical: o Surface interaction (cell squashed between pumps wall) o Bulk flow (flow-induced haemolysis) o stretching of the membrane: Negative pressures of 50-80 mmHg - Chemical: o Poison (snake, insect) o Bacteria toxins o Osmotic pressure effects (C° of water) - Thermal: o Temperatures greater than 42 °C 0 °C -> freezing water -> tensile stress triggered in the stroma o high temperature variation (<10 °C) - biological factors ➔ TILLMANN DIAGRAM Rupture of RBCs stroma is poportinnal to o magnitude of the stress o duration of the stress + CFD modelling studies for complex cases <!> high variability: the animals could have been frightened or had just eaten or were fasting IV- Cardiac physiology Superior (SVC) and inferior vena cava (IVC) -> right atrium (RA) -> right ventricle (RV) -> pulmonary artery (PA) -> lungs -> left atrium (LA) -> left ventricle (LV) -> aorta (Ao) -> different organs of the body - Diastole: => blood in open: mitral and…