Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Week 3 > Biochem > Flashcards

Biochem Flashcards

1
Q

Most common cardiovascular diseases

A
  1. Coronary artery disease

2. Stroke

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Coronary Artery disease

A
  • Build on wall of artery
  • Leads to narrowing and eventually blockage
  • Blockage after 12 hours leads to cell death
  • Heart attack or MI
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Tests for MI

A
  1. Electrocardiogram
  2. Nuclear scan
  3. Coronary angiography
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Symptoms of MI

A
  • Chest pain
  • Upper body discomfort
  • Shortness of breath
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Diabetes and MI

A

MI can occur without symptoms because of nerve damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cardiac biomarkers

A
  • Enzymes
  • Proteins

Show the amount of damage and extent of damage in the heart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Serum enzymes and proteins

A

Serum levels of enzymes and proteins can be a biomarker as it shows damage by showing release of intracellular components

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Serial testing of biomarkers are necessary to ensure that:

A
  1. Rise in blood levels is not missed

2. Estimate severity of the heart attack

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Ideal cardiac biomarker

A
  • cost effective
  • accurate
  • available
  • early appearance and measurable
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

List the former cardiac biomarkers

A
  1. Lactate dehydrogenase
  2. Aspartate aminotransferase (AST)
  3. Myoglobin
  4. Creatine kinase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Lactate dehydrogenase

A
  • Non-specific for cardiac tissue

LD1-5

LDH1: Pancreas, kidney, stomach tissue, RBC

LDH2-4: Platelets

LDH1+2: Cardiac tissue

Acute MI - LDH levels rise at about 10 hrs, peak at 24-48 hrs, elevated up for 8 days

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Aspartate aminotransferase (AST) is also called:

A

Serum glutamate oxaloacetate transminase (SGOT)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Aspartate aminotransferase (AST)

A
  • an enzyme found in heart and liver
  • non-specific and no longer used as an assessment
  • Catalyzes the reversible transfer of an alpha-amino group between aspartate and glutamate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Myoglobin

A
  • heme protein present in heart and skeletal muscles
  • released from damaged tissues
  • increases occur more rapidly than creatine kinase
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Functions of Myoglobin:

A
  1. Reservoir for oxygen

2. As an oxygen carrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why is myoglobin not used on it’s own for assessing MI?

A
  1. short plasma half-life (so metabolized quick)

2. Lack of specificity for cardiac tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is Myoglobin paired with for assessment?

A

Troponins and/or CK-MB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Creatine Kinase formally known as:

A

Creatine phosphokinase (CPK)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Creatine Kinase

A
  • an enzyme
  • present in greatest amounts in skeletal muscle, myocardium, brain
  • small amounts occur in other visceral tissues

Catalyses a reversible reaction: creatine –> phosphocreatine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

CK subunits:

A

B & M

21
Q

CK isoenzymes:

A

CK-MM (muscle)
CK-BB (brain)
CK-MB (high % in heart)

22
Q

% of CK-MB in muscle, brain, heart

A

1,3,29

23
Q

CK elevations

A
  • may be from a variety of non cardiac conditions

- an elevation in total CK is not specific to MI

24
Q

List the new cardiac biomarkers

A
  1. CK-MB

2. Troponin

25
Q

CK-MB

A
  • specific for cardiac tissue
  • rise starts 3-6 hrs after onset of MI
  • peak at 12-24 hrs
  • return to baseline 48-72 hrs
26
Q

CK:CK-MB ratio

A
  • improved specificity
  • higher ratio = more likely MI has occurred

Ratios > 2.5-3 have been proposed for MI

27
Q

Troponin 3 subunits:

A

3 regulatory enzymes:

  • TnC
  • TnT
  • Tnl
28
Q

Troponin attaches to…

A

Tropomyosin (sits between actin filaments in striated muscle) –> needed for non smooth muscle contraction in the skeletal and cardiac muscle

29
Q

Which troponin is not measured and why?

A

Troponin C because it doesn’t have an isoform specific for the heart (could be heart or skeletal muscle)

30
Q

Which troponin(s) are cardiac specific?

A

CTnl and CTnT

31
Q

Which serum levels can be used to diagnose people with MI especially when ECG is inconclusive?

A

CK
CK-MB
cTnl
cTnT

32
Q

Heart-type fatty acid binding protein (H-FABP) function:

A
  • helps intracellular uptake of long chain fatty acids in myocardium
  • still being evaluated for use in MI diagnosis
33
Q

Where does heart-type fatty acid binding protein (H-FABP) go?

A

Due to small size (15 kDA) and location (cytoplasm of cardiac myocytes), releases rapidly into the blood after Myocardial damage

34
Q

What could you combine H-FABP with and why for MI?

A

cTnT because it provides significant improvement in the diagnosis within 4-12 hours

35
Q

CK-MB kinetics

A

Concentration begins to rise between 3-6 hrs and goes back to baseline at 3-4 days

36
Q

cTnl kinetics

A

Concentration begins to rise between 3-6 hrs and goes back to baseline at 7-10 days

37
Q

cTnT kinetics

A

Concentration begins to rise between 2-6 hrs and goes back to baseline at 7-10 days

38
Q

Myoglobin kinetics

A

Concentration begins to rise at 2-3 hrs and goes back to baseline a little after 24 hrs

39
Q

Are troponin levels in serum high or low and why?

A

Normally low because they are intracellular and only released from dead myocytes

after 12 hours of chest pain if troponin levels are still low then heart attack is unlikely

40
Q

What is Angina?

A

Chest discomfort caused by poor blood flow through the blood vessels of the heart muscle with normal cardiac troponin levels

41
Q

Elevated CK-MB levels may be seen in:

A
  • skeletal muscle injury

- cardiac injury other than MI

42
Q

Elevated troponin levels may be seen in:

A
  • ischaemia
  • myocarditis
  • arrhythmia
  • pulmonary embolism
  • high blood pressure
43
Q

Mycarditis

A

inflammation of the heart muscle

44
Q

Arrhythmis

A

abnormal heart rhythm

45
Q

Pulmonary embolism

A

blood clot lodged in the lung

46
Q

High blood pressure

A

hypertension

47
Q

Definition of MI

A
  • evidence of significant increase in troponin (or CK-MB) concentration with time
  • evidence of ischaemia with symptoms of MI
  • new ECG changes
48
Q

Ischaemia

A

sudden reduction of heart muscle blood supply

Week 3 (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions