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Flashcards in Systemic Response to Injury Deck (80)
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1
Q

Protein signaling compounds that mediate cellular responses

A

Cytokines

2
Q

Cytokine: Induces muscle breakdown and cachexia through increased catabolism

A

TNF-α

3
Q

Cytokine: Induces fever through prostaglandin activity in anterior hypothalamus

A

IL-1

4
Q

Cytokine: Promotes β-endorphin release from pituitary

A

IL-1

5
Q

Cytokine: Promotes lymphocyte proliferation and Ig production

A

IL-2

6
Q

Cytokine: Elicited by all immunogenic cells as a mediator of acute phase response

A

IL-6

7
Q

Cytokine: Prolongs activated neutrophil survival

A

IL-6

8
Q

Cytokine: Chemoattractant for neutrophils, basophils, eosinophils, and lymphocytes

A

IL-8

9
Q

Cytokine: Activates macrophages via Th1 cells

A

IFN-γ

10
Q

Protect cells from deleterious effects of traumatic stress and, when released by damaged cells, alert the immune system of the damage

A

Heat shock proteins

11
Q

Bind both autologous and foreign proteins and thereby function as intracellular chaperones for ligands such as bacterial DNA and endotoxin

A

Heat shock proteins

12
Q

Cause cell injury through oxidation of unsaturated fatty acids within cell membranes

A

ROS

13
Q

Derived primarily by oxidation of membrane phospholipid arachidonic acid

A

Eicosanoids

14
Q

Enzyme involved in the oxidation of membrane phospholipid arachidonic acid

A

PLA2

15
Q

Action of phospholipase A2 is inhibited by

A

Corticosteroids

16
Q

Arachidonic acid undergoes the COX pathway to generate (2)

A

Cyclic endoperoxidases

1) PG
2) TXA2

17
Q

Arachidonic acid undergoes the LOX pathway to generate (2)

A

HPETE (5-Hydroperoxyeicosatetraenoic acid)

1) HETE (5-Hydroxyicosatetraenoic acid)
2) Leukotrienes

18
Q

MOA of Aspirin (NSAID prototype)

A

Nonselectively and irreversibly inhibits COX (COX-1 and 2)

19
Q

Aspirin anti-inflammatory effect is mediated by

A

Inhibition of COX-2 thereby inhibition of TXA2 production by platelets and decreases platelet aggregation

20
Q

GI toxicity of NSAIDs is mediated by

A

Inhibition of COX-1 hence PG synthesis (for HCO3 and mucous secretion)

21
Q

A viral illness for which aspirin is used is associated with what syndrome in children

A

Reye syndrome

22
Q

Reye syndrome is characterised by (2)

A

Acute non-inflammatory

1) Encephalopathy
2) Fatty degenerative liver failure

23
Q

Nonselective but reversible COX inhibitors (2)

A

1) Indomethacin

2) Ketorolac

24
Q

Selective COX-2 inhibitor with reduced risk of GI toxicity

A

Celecoxib

25
Q

Anti-inflammatory effect of omega 3 fatty acids (3)

A

1) Inhibits TNF release from hepatic Kupffer cells
2) Inhibits leukocyte adhesion
3) Inhibits leukocyte transmigration

26
Q

Elevated during G- bacteremia, hypotension, hemorrhage, endotoxemia, and tissue injury

A

Kallikrein

27
Q

Action of kinins (6)

A

1) Vasodilation
2) Increased capillary permeability
3) Tissue edema
4) Pain pathway activation
5) Inhibition of gluconeogenesis
6) Increased bronchoconstriction

28
Q

Actions of serotonin

A

1) Vasoconstriction
2) Bronchoconstriction
3) Platelet aggregation

29
Q

Associated with eosinophil and mast cell chemotaxis

A

Histamine (H4)

30
Q

PSY nervous system transmits its efferent signals via

A

Acetylcholine

31
Q

Vagus nerve potentially regulates early pro inflammatory mediator release, specifically

A

TNF

32
Q

CNS regulates inflammation via

A

Vagus nerve

33
Q

Stimulus for cortisol release

A

ACTH

34
Q

In burn-injured patients, cortisol may be chronically elevated for how long

A

4 weeks

35
Q

Cortisol impairs wound-healing by reducing what substances in the wound

A

1) TGF-β

2) IGF-I

36
Q

Principal regulator of steroid synthesis

A

ACTH

37
Q

Sequence in steroid synthesis (3)

A

1) Cholesterol converted to pregnenolone by ACTH
2) Pregnenolone converted to progesterone or 17α-OH-pregnenolone
3) Progesterone converted to 11-Deoxycorticosterone to corticosterone to aldosterone (mineralocorticoid)
3) Progesterone converted to 17α-OH-prrogesterone to 11-deoxycortisol to cortisol (glucocorticoid)
3) 17α-OH-pregnenolone converted to DHEA to androstenedione to testosterone to estradiol (sex steroid)

38
Q

A steroid alcohol

A

Cholesterol

39
Q

Cholesterol is a precursor of (5)

A

1) Cell membranes
2) Vitamin D (7-dehydrocholesterol)
3) Bile salts (cholic and chenodeoxycholic acid)
4) Adrenal hormones (aldosterone and cortisol)
5) Sex hormones (testosterone and estradiol)

40
Q

Cholesterol is composed of (2)

A

1) 4 fused hydrocarbon rings (A-D)
2) 8-membered branched hydrocarbon chain (20-27) attached to the D-ring
3) Single hydroxyl group at C3 of the A ring to which a fatty acid can be attached to form cholesterol esters

41
Q

Counter regulatory mediator that potentially reverses the anti-inflammatory effects of cortisol

A

Macrophage Migration-Inhibiting Factor

42
Q

MMIF is stored and secreted by (2)

A

1) Anterior pituitary

2) Intracellular pools within macrophages

43
Q

GH exerts downstream effects through (2)

A

1) Direct interaction with GH

2) Enhanced hepatic synthesis of IGF-I

44
Q

Actions of GH and IGF-I (3)

A

1) Protein synthesis
2) Insulin resistance
3) Mobilization of fat stores

45
Q

Catecholamines

A

1) Epinephrine
2) Norepinephrine
3) Dopamine

46
Q

Elevations of plasma catecholamine levels last ___ after severe injury

A

24-48h

47
Q

Overall action of insulin

A

Anabolic state

48
Q

Hallmarks of critical illness due to the catabolic effects of circulating mediators (2)

A

1) Insulin resistance

2) Hyperglycemia

49
Q

T/F Hyperglycemia is associated with immunosuppression and increased risk for infection

A

T

50
Q

Normal healthy adult requires how many calories per day

A

22-25 kcal/kg/day

51
Q

Initial hours after surgical or traumatic injury are metabolically associated with (2)

A

1) Reduced total body energy expenditure

2) Urinary nitrogen wasting

52
Q

Short-term fasting, # of days

A

Less than 5 days

53
Q

Principal sources of fuel in healthy adult

A

Protein and lipids

54
Q

Most abundant source of energy in healthy adult

A

Lipids

55
Q

Rapidly and preferentially depleted fuel stores

A

Hepatic glycogen

56
Q

Short-term fasting: Fall of serum glucose concentration within

A

Less than 16 hours

57
Q

Recycling of peripheral lactate and pyruvate for hepatic gluconeogenesis is accomplished by

A

Cori cylce

58
Q

Precursors for hepatic gluconeogenesis

A

1) Peripheral lactate
2) Peripheral pyruvate
3) Alanine from skeletal muscle

59
Q

Cori cycle is also known as

A

Lactic acid cycle

60
Q

Metabolic pathway involving conversion of lactate (from the skeletal muscle) into glucose and brought back to the muscle for utilization

A

Cori cycle

61
Q

Energy expense of Cori cycle

A

4 ATP molecules

62
Q

T/F Lactate production is sufficient to maintain systemic glucose need during short-term fasting

A

F

63
Q

Short-term fasting: Source of substrate for hepatic gluconeogenesis when lactate is insufficient

A

Amino acids

64
Q

Amount of protein that must be degraded daily to provide amino acids for hepatic gluconeogenesis

A

75 g/d for a 70 kg adult

65
Q

Proteolysis during starvation results from

A

1) Decreased insulin

2) Increased cortisol

66
Q

Proteolysis during starvation results in increased excretion of

A

Urinary nitrogen in urine

67
Q

Amount of urinary nitrogen excreted in urine during starvation

A

> =30 g/day

68
Q

Normal amount of urinary nitrogen excreted per day

A

7-10 g

69
Q

Effect on proteolysis by prolonged fasting

A

Reduced to 20 g/d

70
Q

Effect on urinary nitrogen excretion by prolonged fasting

A

2-5 g/day

71
Q

Why proteolysis and urinary nitrogen excretion are decreased during prolonged fasting

A

Adaptation by vital organs by using ketone bodies as their principal source of fuel

72
Q

Ketone bodies become an important source of fuel for the brain after how many days of fasting

A

2

73
Q

Ketone bodies gradually become the principal source of fuel for the brain after how many days of fasting

A

24 days

74
Q

Injuries that poses the highest energy demands (2)

A

1) Major burns

2) Sepsis/peritonitis

75
Q

Principal source of energy during critical illness and stressed states

A

Lipids

76
Q

Lipolysis in injury occurs mainly in response to

A

Catecholamine stimulation of hormone-sensitive TAG lipase

77
Q

Injury and severe infections induce a state of

A

Insulin resistance

78
Q

T/F Increase in plasma glucose level in injury is proportional to the severity of injury

A

T

79
Q

T/F After injury, there is an increase in urinary nitrogen excretion

A

T

80
Q

After an injury, loss of urinary nitrogen corresponds to a loss in lean body mass of ___% per day

A

1.5