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Flashcards in Heme/Onc (U.W.) Deck (72)
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1
Q

Leukocyte Adhesion steps?

A
  1. margination
  2. rolling
  3. crawling
  4. activation
  5. tight adhesion
  6. transmigration
2
Q
L selectin (neutrophils) 
P/E selectin (endothelial cells) 
are involved in?
A
  • rolling via these sialylated carbohydrate groups
3
Q

CD18 (MAC1 and LFA) on neutrophils
ICAM (endothelial cells)
are involved in

A

tight adhesion

4
Q

PECAM involved in?

A

transmigration

5
Q

X-linked Agammaglobulinemia

A
  • defect in Bruton Tyrosine Kinase gene

- Bcells fail to develop, so decrease in all Ig’s and lack of germinal center/ primary follicle

6
Q

CD14 found on

A

macrophages

7
Q

paracortex region of lymph node is populated by

A

T-cells and dendritic cells

8
Q

Acute Intermittent Porphyria symptoms? Deficiency?

A

GI pain with neurological changes ( tingling, concentration difficulty)
- caused by deficiency of Porphobilinogen Deaminase

9
Q

AIP has excess amounts of what? So what is a good treatment?

A

ALA and PBG

ALA synthase downregulation is a treatment. Hemin or glucose can downregulate ALA synthase.

10
Q

genetics of VWF

A

autosomal dominant defect in VWF with variable penetrance (dont forget, factor VIII will be affected too!)

11
Q

Trastuzumab

A

mab against tyrosine kinase receptor HER2 + breast cancer

12
Q

Down’s syndrome is associated with?

A
  • ALL

- AML

13
Q

spherocytosis

A

increased MCHC, decreased MCV, and lack of central pallor

14
Q

localized vs metastatic carcinoid

A
localized carcinoid (only in enterochromaffin cells of SI) vs metastatic (spread to liver)
only carcinoid that has spread to the liver can cause carcinoid syndrome. localized carcinoid will have its products degraded by first pass
15
Q

Dohle bodies

A

light blue(basophilic) peripheral granules in neutrophils. occur in toxic systemic illness like leukemoid reaction

16
Q

Leukemoid reaction

A

leukocytosis with normal/increased LAP
usually in response to infection, malignancy, hemorrhage
its differntiated from leukemias by the increased LAP

17
Q

tingling following a massive blood transfusion

A

due to hypocalcemia from citrate (calcium chelator) found in packed blood

18
Q

how does RNAi work

A

inhibits posttranscriptional mRNA from being translated. usually when RISC binds the mRNA it causes degradation

19
Q

Aplastic Anemia in SS patient caused by

A

ParvoB19, non enveloped ssDNA

20
Q

most common cause of DIC in pregnancy

A

htt causing placental abruption releasing TF causing DIC

21
Q

PNH triad

A

hemolytic anemia, pancytopenia, and thrombosis in strange vessels

(hemosedirin accumulation in kidneys often occurs bc of hemoglobinuria/ chronic hemolysis)

22
Q

absent CD55

A

PNH

23
Q

what is the cause of hemochromatosis

A
  • a defect in HFE protein (which works with transferrin) causes the body to FALSELY indicate that body Fe stores are low. in response, the body starts mechanisms to increase Fe
    (1) decrease Liver hepcidin- allowing an increase in ferroportin– so more Fe can be absorbed from SI and macrophages
    (2) increase DMT1 levels (luminal enterocyte), to increase Fe absorption at SI
    overall – increase in IRON
24
Q

triad seen in Hemochromatosis

A

(1) micronodular cirrhosis
(2) increased skin pigmentation
(3) diabetes

25
Q

hemochrotatosis predisposes to (3)

A
  • HCC and cirrhosis
  • CHF
  • hypogonadism
26
Q

asplenic patient, bacterial risks?

A
#1- strep pneumo 
#2- H. influenzea

osteomyelitis #1 cause is Salmonella (not S.aureus)

27
Q

mutations in what gene is responsible for HIV resistance to HAART therapy

A

pol gene

28
Q

thymic positive selection happens how?

thymic negative selection happens how?

A

only Tcells that have strong affinity for CORTICAL cells presenting self antigens survive

Tcells that have strong affinity for MEDULLARY cells presenting self antigens are apoptosed.

29
Q

How would a proteosome inhibitor help a MM patient

A

MM, a malignancy of the plasma cell, causes over production of proteins such as Ig’s. Without their proteasome working, these proteins if misfolded can accumulate and bring on apoptosis

30
Q

anemia/fatigue, bony pain, fatigue, and HYPERCALCEMIA is suggestive of what disease?

A

multiple myeloma

31
Q

Myoglobin

A
  • used as storage for O2 in skm and cardiac m… only in blood stream upon injury
  • P50 is 1 mmHg (so very high O2 affinity)
  • monomeric ( resembles Hgb monomer ) so “hyperbolic” curve (NOT sigmoid)
32
Q

Isoniazid can predispose to what anemia?

A

Sideroblastic. Isoniazid inhibits the activation of B6 (pyridoxine) which is needed for ALA synthase. This causes decreased heme synthesis, as it is the rate lim step

33
Q

BRCA1/BRCA2

A

autosomal dominant inheritance
a tumor suppressor gene
involved in repair of dsDNA breaks

34
Q

pancytopenia in SLE patient

A
  • because of autoantibodies against RBC (causing warm IgG Coombs+ AIHA), WBC, and platelets
    this is a type II HS reaction (unline lupus glomerulonephritis that is a type III HS reaction)
35
Q

what causes hemorrhagic cystitis in Cyclophosphamide treatment

A

cyclophosphamide is broken down into metabolite “acrolein” to be excreted by kidney, and this substance is toxic to urinary epithelial cells, so use MESNA that can bind and inactivate acrolein

36
Q

t(14;18)

A

BCL2

follicular lymphoma

37
Q

what kind of lung cancer can produce ectopic ACTH

A

small (oat) cell lung cancer

38
Q

pathophys of chronic myeloproliferative disorder

A

a constitutively active JAK2 (which a non-receptor Tyrosine Kinase which is cytoplasmic), this results in consitutive action of the JAK-STAT pathway which promotes growth through transcription

39
Q

what are the enzymes involved in the non-oxidative branch of HMP shunt? what is their purpose?

A

transketolase and transaldolase
they interconvert Ribose 5P between Fructose 6P depending on cell needs
if nucleotides are needed ribose5P is generated
if glycolysis/energy is needed, Fructose6P is generated

40
Q

t(15;17)

A

APL (which is AML M3)

transfusion of RARA and PML

41
Q

nucleolus role?

A

rRNA

only place where RNA pol 1 is found (this synthesizes all rRNA except for 5S rRNA)

42
Q

what remains unchanged in anemia, methemoglobinemia, CO poisoning, polycythemia

A

partial pressure of O2 in blood!

because this value represents the O2 dissolved in PLASMA and is thus unchanged.

43
Q

nitrite inhalation can cause

A

methemoglobinemia

44
Q

what is methemoglobin

A

Iron in the 3+ state (aka the oxidized state) which inhibits its ability to bind O2

45
Q

what causes hypercalcemia in MM

A

IL1 and IL6 being secreted by neoplastic plasma cells cause osteoclast activity. punched out bone lesions will be visible

46
Q

pathophys of CO poisoning

A

CO poisoning causes increase in carboxyhemoglobin because CO binds RBC with 250x greater affinity that O2 can. (please not that the Fe in RBC is NOT affected)
this causes less O2 to bind to RBCs
a leftward shift in RBC O2 dissociation curve

47
Q

Fanconi Syndrome

A

inherited form of anaplastic anemia that is notable for short stature and missing thumbs

48
Q

opiod tolerance to what symptoms dont occur

A

constipation and miosis

49
Q

which cancer am I: round, medium size uniform tumor cells with ki67> 99% (which refers to proliferation fraction)

A

Burkitt’s lymphoma

50
Q

pancreatic insufficiency is linked to what kinds of anemia?

A

Megaloblastic

(1) if pancreatitis bc chronic alcoholic- folate def
(2) decreased pancreatic secretions means pancreatic enzymes are not available to cleave R-binding factor. R-binding factor binds B12 and must be cleaved so B12 can bind IF and be absorbed

51
Q

G6PD mode of inheritance

A

XR

52
Q

SSD does what to the spleen

A

atrophy, fibrosis and scarring due to repeated splenic infarctions, resulting in auto-splenectomy

53
Q

aplastic crisis vs aplastic anemia in lab

A

aplastic crisis only affects RBCs. aplastic anemia should show pancytopenia

54
Q

what happens in the germinal centers of follicles?

A

Isotype Switching (Heavy chain rearrangement which is Tcell dependent) to help make Ig’s from the initial IgM

55
Q

hepcidin is made where?

A

hepatic parenchyma

56
Q

what inactivates 6MP? what activates it?

A

XO inactivates

HGPRT activates

57
Q

what does 2,3 BPG do? who doesnt bind well to it?

A

facilitates O2 release in peripheral tissues

HbF doesn’t bind well to it bc of lack of positive charge at 2,3 BPG binding pocket

58
Q

why do erythrocytes sometimes not make ATP in glycolysis

A

once they get to the 1,3BPG step they sometimes opt to make 2,3BPG via BPG mutase instead of continuing glycolysis and getting ATP

59
Q

osteolytic (lucent) vs osteoblastic (sclerotic) bone mets

A

if lytic then think: MM, RCC, NSCLC, non Hodgekin, melanoma

if blastic then think: PCa, SCLC, Hodgekins’

60
Q

MDR1

A

codes of P glycoprotein which is a ATP depedent efflux pump

61
Q

angiogenesis is mediated by what factors

A

VEGF (IL1, Infy)

FGF

62
Q

a mutation in what will make anti-EGFR therapy ineffective

A

KRAS (b/c KRAS causes constitutional EGFR activation)

63
Q

what do microsomal monooxygenases do (ex: cyp450 monooxygenase) in cancer

A

most carcinogens (benzene etc) are delivered to the body in an inactive pro-carcinogen phase, microsomal monoxygenases (apart from metabolizing drugs) can metabolize these pro-carcinogens into CARCINOGENS

64
Q

EBV-
what cell does it infect?
what cell proliferates in response (aka seen on blood smear)

A

infects: CD21+ B lymphocytes

CD8+ cytotoxic lymphocytes proliferate in response to infection

65
Q

Cyanide toxicity treatment?

A

Nitrites. Because they create methemoglobin. Cyanide is more attracted to Fe3+ so it binds the methemoglobin and stops wreaking havoc on the mitochondrial cytochrome enzymes

66
Q

what kind of gene is KRAS

A

PROTO-oncogene

67
Q

which drugs can induce aplastic anemia

A

chloramphenicol, carbamazepine, sulfonamides

68
Q

cells that look like “wrinkled tissue paper”

A

Gaucher’s! these are macrophages with glucocerebroside accumulated.
AR
pancytopenia, hepatosplenomegaly

69
Q

what causes the green color of a bruise

A

Heme Oxygenase that converts heme to BILIVERDIN

70
Q

what is the monospot test

A

+ if patient serum causes agglutination of a horse’s RBCs

71
Q

how to differentiate AML vs CML by labs

A

AML has >20% blasts

CML has lower numbers of blasts

72
Q

LAP neg

A

CML