Brainscape's Knowledge GenomeTM

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


See full index

HEMATOLOGY 1 > other notes from hema > Flashcards

other notes from hema Flashcards

1
Q

Master regulatory hormone of systemic iron metabolism

A

Hepcidin (produced by the liver)

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

Effect of decreased iron stores on plasma iron

A

Decreases plasma iron, leading to liver alert and hepcidin production stops

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

Effect of decreased hepcidin production

A

Ferroportin in enterocyte and macrophage membranes becomes active, increasing iron absorption and recycling

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

Effect of increased plasma iron on hepcidin production

A

Plasma iron increases, iron stores increase, liver alerts and produces hepcidin

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

Effect of hepcidin on ferroportin

A

Inactivates ferroportin in enterocyte and macrophage membranes, reducing iron absorption and recycling

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

Hemochromatosis protein (HFE)

A

Hepatocyte membrane

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

Transferrin receptor 2 (TfR2)

A

Hepatocyte membrane

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

Bone morphogenic protein (BMP)

A

Secreted product of macrophages

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

Bone morphogenic protein receptor (BMPR)

A

Hepatocyte (and other cells) membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Hemojuvelin (HJV)

A

Hepatocyte membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

SMAD (sons of mothers against decapentaplegic)

A

Hepatocyte (and other cells) cytoplasm

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

Absorption sites for iron

A

Duodenum and upper jejunum

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

Foods with high iron levels

A

Red meats, legumes, dark green leafy vegetables

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Iron forms for absorption

A

Ionic iron (Fe+2, ferrous) and heme (nonionic)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Most common dietary iron form

A

Fe+3 (ferric), especially in plant sources, poorly absorbed

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

Factors inhibiting iron absorption

A

Oxalates, phytates, phosphates, calcium

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

Enhancers of iron absorption

A

Gastric acid, acidic foods (citrus), DcytB (duodenal cytochrome B)

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

Heme iron absorption

A

More readily absorbed than ionic iron; found in meat (myoglobin, hemoglobin)

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

Ferrous iron (Fe+2) transport

A

Carried by DMT1 (divalent metal transporter 1) across enterocyte membrane

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

Transport of absorbed iron

A

Requires ferroportin; Hephaestin reoxidizes Fe+2 to Fe+3 for transport into blood

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Hephaestin function

A

Oxidizes iron as it exits the enterocyte for plasma transport.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Iron transport protein

A

Transferrin, formed when apotransferrin binds ferric (Fe+3) iron.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Receptor for transferrin

A

Transferrin receptor 1 (TfR1) on cell membranes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Iron use in cells

A

Transferred into mitochondria for cytochrome or heme production, or stored as ferritin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Storage form of iron in cells

A

Ferritin, stored in cells with excess iron, especially in macrophages and hepatocytes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Ferritin characteristics

A

Intracellular protein secreted by macrophages, an acute phase reactant (APR) elevated in inflammation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Ferritin degradation

A

Iron is released from ferritin by degradation in lysosomes.

28
Q

Hemosiderin

A

Partially degraded ferritin, seen in iron overload, detectable using Prussian blue iron stain.

29
Q

Iron excretion mechanism

A

Minimal daily loss via exfoliation; no active excretion.

30
Q

Iron’s role in cells

A

Essential for energy production and oxygen transport in hemoglobin.

31
Q

Iron recycling source

A

Primarily from aging RBCs degraded by splenic macrophages.

32
Q

Macrophage iron storage

A

Stores iron from hemoglobin as ferritin.

33
Q

Macrophage iron export

A

Uses ferroportin to export iron to other cells.

34
Q

Plasma proteins in iron recycling

A

Haptoglobin saves hemoglobin; hemopexin saves heme.

35
Q

Hepatocyte role in recycling

A

Exports stored iron via ferroportin to transferrin.

36
Q

Main functional iron compartment in blood

A

Hemoglobin iron (~68%).

37
Q

Functional iron in muscles

A

Myoglobin iron (~10%).

38
Q

Functional iron in cellular enzymes

A

Peroxidase, catalase, cytochromes (~3%).

39
Q

Primary iron storage forms

A

Ferritin and hemosiderin in macrophages and hepatocytes (~18%).

40
Q

Iron storage exceptions in cells

A

Mature RBCs do not store iron.

41
Q

Iron transport mechanism in plasma

A

Transferrin (<1%).

42
Q

Serum iron reference range and use

A

50 to 160 μg/dL; used for diagnosing disorders of iron metabolism.

43
Q

Serum iron specimen requirements

A

Nonhemolyzed serum, collected in the morning after 12-hour fasting.

44
Q

TIBC reference range and purpose

A

250 to 400 μg/dL; indirectly measures transferrin concentration via iron-binding ability.

45
Q

TIBC specimen requirements

A

Nonhemolyzed serum, 12-hour fasting; values are time-independent.

46
Q

Transferrin iron saturation range and calculation

A

20% to 55%; (Serum Iron / TIBC) x 100.

47
Q

Serum ferritin reference range for men and women

A

40 to 400 ng/mL (men), 12 to 160 ng/mL (women).

48
Q

Significance of serum ferritin test

A

Reflects tissue iron stores; first indicator of declining iron storage.

49
Q

Test used for direct visualization of tissue iron stores

A

Prussian Blue staining of bone marrow or liver biopsy.

50
Q

Prussian Blue staining mechanism

A

Uses acidic potassium ferrocyanide; ferric iron forms visible Fe7(CN)18 (Prussian blue) compound.

51
Q

Prussian Blue stain as a diagnostic tool

A

Gold standard for assessing tissue iron; detects hemosiderin but not ferritin.

52
Q

Serum iron reference range and use

A

50 to 160 μg/dL; used for diagnosing disorders of iron metabolism.

53
Q

Serum iron specimen requirements

A

Nonhemolyzed serum, collected in the morning after 12-hour fasting.

54
Q

TIBC reference range and purpose

A

250 to 400 μg/dL; indirectly measures transferrin concentration via iron-binding ability.

55
Q

TIBC specimen requirements

A

Nonhemolyzed serum, 12-hour fasting; values are time-independent.

56
Q

Transferrin iron saturation range and calculation

A

20% to 55%; (Serum Iron / TIBC) x 100.

57
Q

Serum ferritin reference range for men and women

A

40 to 400 ng/mL (men), 12 to 160 ng/mL (women).

58
Q

Significance of serum ferritin test

A

Reflects tissue iron stores; first indicator of declining iron storage.

59
Q

Test used for direct visualization of tissue iron stores

A

Prussian Blue staining of bone marrow or liver biopsy.

60
Q

Prussian Blue staining mechanism

A

Uses acidic potassium ferrocyanide; ferric iron forms visible Fe7(CN)18 (Prussian blue) compound.

61
Q

Prussian Blue stain as a diagnostic tool

A

Gold standard for assessing tissue iron; detects hemosiderin but not ferritin.

62
Q

Increased tissue iron stores without tissue damage; may progress to hemochromatosis.

A

Hemosiderosis

63
Q

Increased iron accumulation in body tissues causing tissue damage.

A

Hemochromatosis

64
Q

Most common form of iron overload disease

A

Hereditary Hemochromatosis (Bronze Diabetes)

65
Q

Genetic cause of Hereditary Hemochromatosis

A

Mutations in the HFE gene regulating dietary iron absorption

66
Q

Symptoms of Hereditary Hemochromatosis

A

Arthritis, liver cirrhosis, congestive heart failure, impotence, bronze skin, diabetes, thyroid deficiency

67
Q

Treatment approaches for Hereditary Hemochromatosis

A

Avoiding iron-rich foods, phlebotomy, Deferoxamine (Desferal)

HEMATOLOGY 1 (27 decks)

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