Exam 5 - Antimalarial Flashcards
Malaria:
what are the different parasites?
plasmodium falciparum*** plasmodium vivax*** - causes relapses plasmodium ovale -- causes relapses plasmodium malariae plasmodium knowlesi *** = most common
what vaccine is available for malaria?
noneee
Life Cycle of Plasmodium Falciparum:
1. infected ______ inject _______
mosquito
sporozoites
Life Cycle of Plasmodium Falciparum:
2. Sporozites migrate to the _____ where they become _______
liver;
merozoites
Life Cycle of Plasmodium Falciparum:
3. Merozoites are released and invade ______
red blood cells
Life Cycle of Plasmodium Falciparum:
4. Once the merozoite is in the red blood cel it becomes a _______
trophozoite
Life Cycle of Plasmodium Falciparum:
Some merozoites can become ________ (not just trophozoite)
gametocytes
Ways to prevent malaria?
Prevention: insect repellents/insecticides/bed nets
or Chemoprophylaxis
what are some common malaria chemoprophylaxis
- atovaquone-proguanil
- chloroquine
- mefloquine
- primaquine
how are antimalarial drugs classified?
based on what stage the drug kills the malaria bugs
what are the 3 different stages a drug could attack the malaria?
tissue schizonticides
blood schizonticides
gametocytocides
tissue schizonticides: kill the ______ parasites
liver stage
blood schizonticides kills ______ forms
erythrocytic
gametocytocides: kill the _______ and block ______
sexual stages;
block transmission
what are the 6 different antimalarial drug classes
artemisinin 4-aminoquinolines 8-aminoquinolines atovaquone antifolates antibiotics
Artemisinin:
High or low toxicity?
Works fast or low?
LOW toxicity
and works fast (but also lasts not a long time..)
MOA of Artemisinin:
must be activated via _______
once activated it may form ________
and targets parasite proteins and lipids
via heme-iron
form free radicals
Artemisinin mechanism of resistance:
Mutations in _____ gene and causes _________
kelch 13; delays in progression through the life cycle
how does kelch13 work against artemisinin?
it enhances the stress response/helps malaria resist the drug
Artemisinin:
is active against what form of malaria?
blood schizonticide
Artemisinin:
bolus or infusion is best and why?
bolus bc PEAK/MIC is how it works
Artemisinin gets converted to ________ which is the active part
dihydroartemisinin
what drugs are 4-aminoquinolines
quinine
chloroquine
mefloquine
the -N group on the 4-aminoquinolines is a (weak or strong) (acid or base)
and what is that substiuients role
weak base
assists in drug accumulation via pH trapping
Malaria and its mechanism:
it ingests _______ from host cells
hemoglobin
Malaria and its mechanism:
it degrades hemoglobin to amino acids and _______ (which is toxic) in the food vacuole
free heme