Cardiac Function Testing Completed Confidence Ex. Reading Module MBC BY3BC1 = Things to do: · Type Lecture What do we use Biochemical Tests/Biomarkers for? · Diagnosis · e.g if you knew there was a particular protein that would appear in the blood if an organ was deteriorating . we could run a test to quantify the level of that protein · HIV - look at the quantity of virus particulars · Management · Progression of disease . can look at the number of viruses during the · Response to treatment . look at how the patient is going with the treatment · Recurrence of disease · Screening - detection in asymptomatic individuals · population - newborn screening · selected group - obese patients for type II diabetes mellitus · Individual - familial hypercholesterolaemia Assay of Serum Biomarkers Cardiac Function Testing 1
. best biomarker for the heart is to run an assay for a serum (component in the blood) enzyme/protein · Use a colourometric assay · you are looking for a specific protein and as you release an antibody for that protein it will bind and cause a colour change . the intensity of the colour is in direct proportion of the concentration of the enzyme · Enzyme activity: · Rate of change in absorbance e.g. aspartate aminotransferase 16 12 Molar absorbance x 10-3 8 NAD NADH 240 280 320 360 Wavelength (am) Aspartate + 2-oxoglutarate glutamate + oxaloacetate Oxaloacetate + NADH + H* malate + NAD+ aspartate aminotransferase activity ( umol/min/ml) = 6.22 x 1 Change in absorbance per min Extinction coefficient for NADH = 6.22 mM-1 cm1 · Amount of protein/enzyme: · Immunological methods e.g. ELISA · Enzyme-linked immunosorbent assay Substrate Substrate Substrate Substrate Secondary Antibody Conjugate Inhibitor Antigen Primary Antibody Conjugate Capture Antibody Ag DIRECT ELISA INDIRECT ELISA SANDWICH ELISA COMPETITIVE ELISA · sandwich elisa is the best way to do it - more expensive · Metabolites: · Enzymatic or chemical convention to a coloured product Cardiac Function Testing 2
· Spectrophotemetric measurements · Beer-Lambert law Acute Myocardial Infection · imbalance between myocardial oxygen supply and demand · results in muscle injury / death · often caused by coronary thrombosis · vessels become blocked because of fissure / rupture of the intimal surface of an atheromatous plaque Cardiac Function Testing 3