Exam 5 - Antimalarial and Antiparasitics LaCount

Question 1

pediculosis is also known as ____

Answer 1

lice

Question 2

most common symptom of lice

Answer 2

itching

Question 3

lice is mainly spread by _______ ________

Answer 3

direct contact

Question 4

adult lice live ~ ____ days on human head

a. 3
b. 15
c. 30
d. 180

Answer 4

c. 30

Question 5

Spinosad belongs to which drug class?

a. Nicotinic Acetylcholine Receptor Agonist
b. GABA Receptor Antagonist
c. Sodium Channel Modulator
d. Glutamate-Gated Chloride Channel Activator

Answer 5

a. Nicotinic Acetylcholine Receptor Agonist

Question 6

spinosad MOA: rapid excitation of the insect ______ ______ causes death

Answer 6

nervous system

Question 7

spinosad targets which part of lice?

a. cardiovascular system
b. respiratory system
c. endocrine system
d. nervous system

Answer 7

d. nervous system

Question 8

which of the following is FALSE about perethrins for lice?

a. Esters of chrysanthemic acid (II is more effective)
b. nerve membrane sodium channel toxins that also affect potassium channels
c. Rapidly metabolized if absorbed – relatively nontoxic
d. Piperonyl butoxide synergistically enhances activity

Answer 8

b. nerve membrane sodium channel toxins that also affect potassium channels

(do not affect potassium channels)

Question 9

how long do helminth (worm) infections last?

Answer 9

they are chronic - last for the lifetime of host

Question 10

most common helminthic infection worldwide

Answer 10

enterobius vermicularis

Question 11

pinworm infection is also known as ________

Answer 11

enterobiasis

Question 12

how is enterobiasis (pinworm infection) transmitted?

a. sexual transmission
b. direct contact
c. fecal-oral transmission
d. airborne droplets

Answer 12

c. fecal-oral transmission

Question 13

diagnosis for pinworm infection

a. CT scan
b. tape test
c. tropism assay
d. blood cultures

Answer 13

b. tape test

Question 14

benzimidazoles common ending

Answer 14

-bendazole

Question 15

4 benzimidazoles currently on the market

Answer 15

mebendazole
thiabendazole
albendazole
triclabendazole

Question 16

1st in this class (benzimidazoles)

a. mebendazole
b. thiabendazole
c. albendazole
d. triclabendazole

Answer 16

a. mebendazole

Question 17

toxicity limits use; no longer recommended due to toxicity and potential teratogen

a. mebendazole
b. thiabendazole
c. albendazole
d. triclabendazole

Answer 17

b. thiabendazole

Question 18

Useful against both GI and tissue infections

a. mebendazole
b. thiabendazole
c. albendazole
d. triclabendazole

Answer 18

c. albendazole

Question 19

Used in combination with ivermectin to treat Fasciola hepatica (liver flukes), roundworms and ectoparasites

a. mebendazole
b. thiabendazole
c. albendazole
d. triclabendazole

Answer 19

d. triclabendazole

Question 20

what drug class is used for helminths?

Answer 20

benzimidazoles (drugs ending in -bendazole)

Question 21

which of the following is FALSE about the MOA of benzimidazoles?

a. binds to tubulin
b. inhibits formation of microtubules
c. can bind to mammalian tubulin
d. none of the above

Answer 21

d. none of the above

(they are all true)

Question 22

which of the following is TRUE about benzimidazoles and inhibition of microtubules?

a. Microtubules grow from “minus” end
b. Benzimidazoles cap microtubules
c. Microtubules continue to be shortened from plus end
d. Inhibits RNA transcription, secretion of parasite molecules, glucose uptake

Answer 22

b. Benzimidazoles cap microtubules

(a. is “plus” end; c. is minus end; d. inhibits cell division)

Question 23

Drug of choice for pinworms; Also used for cysticercosis, hookworms, ascariasis, trichuriasis, and strongyloidiasis

a. mebendazole
b. thiabendazole
c. albendazole
d. triclabendazole

Answer 23

c. albendazole

Question 24

active metabolite of albendazole

a. albendazole oxide
b. albendazole sulfoxide
c. albendazole deoxycholate
d. albendazole endoperoxide

Answer 24

b. albendazole sulfoxide

Question 25

Used for pinworms, hookworms, ascariasis, and trichuriasis; should not be used in pregnant women a. mebendazole b. thiabendazole c. albendazole d. triclabendazole

Answer 25

a. mebendazole

Question 26

-Depolarizing Neuromuscular blocking agent -Causes release of acetylcholine and inhibition of cholinesterase a. albendazole b. pyrantel pamoate c. artemisinin d. 4-substituted quinolines

Answer 26

b. pyrantel pamoate (worms are paralyzed and expelled)

Question 27

T or F: pyrantel pamoate is available OTC for antihelminth therapy

Answer 27

T

Question 28

pyrantel pamoate is highly effective for tx of which of the following? SELECT ALL THAT APPLY (2) a. pinworms b. hookworms c. ascariasis d. trichuriasis

Answer 28

a, c

Question 29

one vaccine available for malaria

Answer 29

RTS, S

Question 30

5 human malaria parasites

Answer 30

Plasmodium falciparum Plasmodium vivax Plasmodium ovale Plasmodium malariae Plasmodium knowlesi

Question 31

responsible for most malaria deaths a. Plasmodium falciparum b. Plasmodium vivax c. Plasmodium ovale d. Plasmodium malariae e. Plasmodium knowlesi

Answer 31

a. Plasmodium falciparum

Question 32

relapsing malaria - caused by hypnozoites in liver a. Plasmodium falciparum b. Plasmodium vivax c. Plasmodium ovale d. Plasmodium malariae e. Plasmodium knowlesi

Answer 32

b. Plasmodium vivax

Question 33

72 hour life cycle a. Plasmodium falciparum b. Plasmodium vivax c. Plasmodium ovale d. Plasmodium malariae e. Plasmodium knowlesi

Answer 33

d. Plasmodium malariae

Question 34

how long is the liver stage for plasmodium falciparum?

Answer 34

7 days

Question 35

look at the life cycle of plasmodium falciparum (slide 19)

Answer 35

okay

Question 36

antimalarial drugs: kill liver stage parasites a. tissue schizonticides b. blood schizonticides c. gametocytocides

Answer 36

a. tissue schizonticides

Question 37

antimalarial drugs: kill erythrocytic forms a. tissue schizonticides b. blood schizonticides c. gametocytocides

Answer 37

b. blood schizonticides

Question 38

antimalarial drugs: Kill sexual stages; Block transmission a. tissue schizonticides b. blood schizonticides c. gametocytocides

Answer 38

c. gametocytocides

Question 39

active group of artemisinin

Answer 39

endoperoxide

Question 40

antimalarial drugs (6; some are drug classes)

Answer 40

artemisinin 4-aminoquinolines 8-aminoquinolines atovaquone antifolates antibiotics

Question 41

which of the following is NOT a possible MOA of artemisinin? a. targets components of the apicoplast b. Must be activated – likely via heme-iron in food vacuole c. Activated artemisinin may form free radicals d. May inhibit phosphatidylinositol-3-kinase (PfPI3K)

Answer 41

a. targets components of the apicoplast (this is for antibiotics as antimalarial drugs such as tetracycline, doxy, clinda)

Question 42

which of the following is NOT part of the MOA of artemisinin and free radicals? a. acetylates parasite proteins, lipids, DNA b. triggers unfolded protein response c. inhibits translation, proteasome, mitochondria

Answer 42

a. acetylates parasite proteins, lipids, DNA (alkylates not acetylates)

Question 43

artemisinin is not active against _____ _____ or hyponzoites

Answer 43

liver stage

Question 44

T or F: artemisinin is commonly paired with longer half-life drugs

Answer 44

T (artemisinin provides rapid knockdown, longer half-life component eliminates remaining parasites)

Question 45

most common drug used in combo with artemisinin a. lumafantrine b. amodiaquine c. mefloquine d. piperaquine

Answer 45

a. lumafantrine

Question 46

semisynthetic artemisinins are all converted to _____________ (active form) a. methylartemisinin b. dihydroartemisinin c. hydroxyartemisinin d. artemisinin sulfoxide

Answer 46

b. dihydroartemisinin

Question 47

T or F: artemisinin is IV only

Answer 47

F (PO only; semisynthetic artemisinins have different routes of administration)

Question 48

which of the following is NOT a route of administration for semisynthetic artemisinins? a. oral b. IM c. IV d. intrathecal e. rectal

Answer 48

d. intrathecal

Question 49

artemisinin resistance is due to mutations in which gene? a. KatG b. Kelch 13 c. NAT2 d. atpE

Answer 49

b. Kelch 13

Question 50

4-aminoquinolines important structural features (3)

Answer 50

-Cl inhibits formation of beta-haematin -Fe(III)PPIX complexing group -weak bases assist in drug accum via pH trapping

Question 51

which of the following is FALSE about hemoglobin metabolism in malaria? a. Malaria parasites ingest hemoglobin from host cell b. Degrade hemoglobin to amino acids, free fatty acids, and free heme in food vacuole c. free heme is toxic d. Parasite polymerizes heme into hemozoin (nontoxic) e. Chloroquine accumulates in food vacuole and inhibits heme polymerization

Answer 51

b. Degrade hemoglobin to amino acids, free fatty acids, and free heme in food vacuole (AAs and free heme, NOT free fatty acids)

Question 52

4-aminoquinoline DOC

Answer 52

chloroquine

Question 53

4-substituted quinolines interfere with _______ _______ a. cell division b. heme polymerization c. ATP synthesis

Answer 53

b. heme polymerization

Question 54

4-subsituted quinolines resistance

Answer 54

associated with lack of accumulation in food vacuole

Question 55

initial half life of chloroquine: ____-____ days terminal half life of chloroquine: ____-____ months

Answer 55

3-5 days 1-2 months

Question 56

hydroxychloroquine is the same as chloroquine, but with a _______ at end of side chain, which makes it more _____ soluble

Answer 56

hydroxyl; water

Question 57

PRIMARY mechanism of chloroquine resistance a. over-expression of PfMDR1 b. mutations in Kelch 13 c. mutations in PfCRT1 d. mutations in pncA

Answer 57

c. mutations in PfCRT1 (a. is not the primary mech; b. is artemisinin)

Question 58

T or F: chloroquine has P. falciparum cross resistance with mefloquine or quinine

Answer 58

F

Question 59

DOC for liver stages of P. vivax and P. ovale (in combo with chloroquine) a. artemisinin b. primaquine c. doxycycline d. pyrantel pamoate e. albendazole

Answer 59

b. primaquine

Question 60

primaquine drug class a. 4-amionquinoline b. 8-aminoquinoline c. allylamines d. benzimidazole

Answer 60

b. 8-aminoquinoline (a. is chloroquine; c. is terbinafine; d. are the "-bendazoles")

Question 61

primaquine is metabolized by a. CYP3A4 b. CYP2C9 c. CYP2D6 d. CYP2E1

Answer 61

c. CYP2D6 (metabolism required for activity)

Question 62

primaquine's MOA involves spontaneous oxidation producing _______ _______, which kills plasmodium parasites

Answer 62

hydrogen peroxide (H2O2)

Question 63

compound related to primaquine (slide 35)

Answer 63

tafenoquine

Question 64

step 1 of primaquine mechanism: _______ by CYP2D6 a. hydroxylation b. acetylation c. oxidation d. adenylation

Answer 64

a. hydroxylation

Question 65

what testing should be done for primaquine?

Answer 65

G6PD testing

Question 66

primaquine has high risk of _______ in pts with G6PD deficiency a. pancreatitis b. tendon rupture c. hemolysis d. adrenal insufficiency

Answer 66

c. hemolysis

Question 67

primaquine CIs (2)

Answer 67

-Granulocytopenia -Concurrent use of other potentially hemolytic drugs or drugs that suppress myeloid cell development

Question 68

T or F: primaquine should not be used in pregnant women

Answer 68

T

Question 69

which antibiotic is NOT an antimalarial blood schizonticide? a. tetracycline b. doxy c. clinda d. cephalexin

Answer 69

d. cephalexin

Question 70

tetra, doxy, clinda target components of the _______, a plant-like organelle that carreis out many essential biochemical processes a. chloroplast b. apicoplast c. chlorophyll d. mitochondria

Answer 70

b. apicoplast

Question 71

-commonly paired with quinine or quinidine for treatment of falciparum malaria -used for chemoprophylaxsis in areas with high resistance to mefloquine a. tetra b. doxy c. clinda

Answer 71

b. doxy