Practical Flashcards
Cockcroft–Gault equation “*Body weight – Age - Sex” to give Creatinineclearance(mL/min)
[140 - age(yrs)] x weight(kg)
- 23 (OR 1.04 fem.) x serum creatinine (mmol)
Equation for GFR when doing the creatinine clearance (ml/min) test
[plasma creatinine] x 24 x 60 min
*in lab: convert mM to uM
function/purpose of tungstic acid, alumininum silicilate (Lloyd’s reagent) & picric acid
- Tungstic acid: precipitates plasma proteins
- Alumininum silicilate (lloyd’s reagent): bind & isolates creatinine
- Picric acid: makes creatinine (& proteins) chromogen = Jaffe reaction
How to detect glucose with glucose oxidase & peroxidase
Beta-D-glucose (oxidises) -> D- gluconolactone + *H2O2
H2O2 peroxidase + … + … => quinoneimine dye
Glucose threshold levels for normal & diabetes mellitus (DM) in fasting state & 2h of OGTT
Normal - Fasting: 3.5 - 5.5 mM - OGTT: <7.0 mM DM - Fasting: >7.0 mM - OGTT: >11.0 mM
Describe the HbAc1 (glycated Hb) test
- Hb + Glucose bound by covalent bond
- fasting not required
- av blood glucose for 1-3 months
> for blood glu control & dx diabetes - <6% low risk for developing disease associated w diabetes
Whats autophagy
- auto = self + phagy = eat
- self degradation of cells
- discovered by Professor Yoshinori
Lactose intolerance definition
- lack enzyme B-galactosidase (lactase) in small intestine ≠ break lactose down into glucose and galactose
=> lactose fermented => H2, CH4 and CO2 = abdominal pain.
_% of people who are lactose intolerant
75%
Discus how can you manage lactose intolerant. (4)
- avoid lactose
- substitute to maintain nutrient intake,
- regulate calcium intake,
- use of enzyme substitute (immobilized lactase)
- ingest yoghurt w/ lactobacilli
3 tratments for lactose intolerance
- drugs w/ lactase
- lactobacillus acidophilus
- lactose-free products
advantages of immobilised enzymes vs free enzymes
saves time & money
bc enzymes can be separated from product and reused. (not lost after first use = expensive)
5 types of immobilisation techniques
- Adsorption: held by weak physical bond
- Covalent: held by strong chemical bond
- Encapsulation: contain enzymes in semi-permeable membrane
- Entrapment: enzymes trapped in gel matrix = pores allow entry of R & exit of P but not Enz
- Cross-linking: bind enzyme tog.
describe 4 types of lactose intolerance
- 1º lactose intolerance: getting older = # of lactase decrease
- 2º “ “: injury to SI from infection or disease
- Developmental “ “: occur in premature babies and usually improves over a short period of time.
- Congenital “ “: little or no lactase is made from birth (extremely rare genetic disorder)
describe the lactose tolerance BLOOD test
- fast overnight
- 5 blood samples taken = 1x initial & 4x after ingesting 50g of lactose
- lactose intoleranct if blood glucose lvls rise <20mg/dL (1.11 mmol/L)
Blood lactose intolerant test should not be done on and why?
1) ppl w/ Diabetes bc already have hyperglycemia
2) babies bc causes them severe diahorrea
describe the lactose tolerance HYDROGEN BREATH test
- fast overnight
- 25g lactose given
- lactose intolerant = enteric bacteria breaks it down = H (& methane) => detects H in breath
- diabetic ppl can do this test
describe the lactose tolerance STOOL ACIDITY test
- baby given lactose to drink
- if lactose not digested = bacteria in colon breaks down = acidic stools = pH <5.5
Rules of westgard
a. 1 2s = warning
b. 2 2s = REJECT
c. 1 3s = REJECT
d. R4s = one value exceeds +2SD & -2SD
e. 4 1s = 4x points above a SD consecutively (in a row)
f. 10x = 10x points above a SD consecutively = REJECT
dehydration only affects (a)
wheras enal failure affects (a) & (b)
(a) urea
(b) creatinine
describe size-exclusion chromatography
- large molecules travel quicker bc can’t fit in pores of beads
- small molecules move slower as they move in & out of pore beads
MDRD equ. takes account _
ehtnicity
