Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
33 Cards in this Set
- Front
- Back
|
what are the main targets for anti-fungals
|
ergosterol synth and in the membrane, cell wall synth, microtubules, nucleotide synthesis
|
|
|
what is the major drawback of most antifungals
|
toxicity (use topicals)
|
|
|
how do polyenes work
|
they bind to the strol and disrupt the membrane resulting in leakage
|
|
|
what is the drug of choice for many non-topical mycoses
|
Amp B
|
|
|
how do you get resistance to Amp B
|
no ergosterol in the membrane, reduced oxidative damage, cell wall permeability change
|
|
|
what are the three main polyenes
|
amp B, nystatin, pimaricin
|
|
|
Amp B is administered how?
|
I.V.
|
|
|
what is the main side effect of Amp B
|
nephrotoxicity
|
|
|
what are the advantages of lipid formulas of AmpB
|
decreased toxicity ONLY not more effective and expensive
|
|
|
Nystatin is used how?
|
topically and orally
|
|
|
what is the problem with oral nystatin
|
not absorbed well by GI
|
|
|
what was the 1st polyene discovered
|
nystatin (not well absorbed)
|
|
|
what are the Azoles
|
fluconazole, ketoconazole, itraconazole
|
|
|
how do azoles work
|
inhibit cytochrome P450 demethylation of lanosterol so ergosterol can't be made
|
|
|
what azole is currently the drug of choice for non-life threatening fungal infections
|
triazole (i.v. and orally)
|
|
|
what are examples of allylamines
|
naftifine, and terbinafine
|
|
|
how do allylamines work?
|
inhibit squalene epoxidase (used to synthesize ergosterol)
|
|
|
what is a problem with allylamines
|
generate a toxic intracellular squalene buildup
|
|
|
is allylamine hydrophilic or hydrophobic
|
hydrophobic
|
|
|
what do we use allylamines for?
|
mostly dermatophytes
|
|
|
what allylamine is available as an oral formula
|
terbinafine
|
|
|
how do organisms become resistant to allylamines
|
enzyme target modification, poor penetration, overproduction of target enzyme
|
|
|
what are some examples of candins
|
echinocandin, papulocandin, caspofungin and micafungin
|
|
|
how do the candins work
|
noncompetitive inhibition of B 1,3 glucan synthase which makes the cell wall * may really affect the regulation proteins
|
|
|
when would you use a candin
|
candidiasis and secondary therapy maybe for aspergillous not much use against others
|
|
|
how can fungi develop resistance to candins
|
modify enzyme target and have low levels of B 1,3 glucan in the walls
|
|
|
how do nucleoside analogs work?
|
inhibits nucleotide synthesis and converts to 5 fluorouricil in the cytoplasm to stop DNA and RNA synth
|
|
|
what do nucleosides convert to?
|
5 fluorouricil
|
|
|
when do you use nucleosides
|
with amp B (resitance develops quickly)
|
|
|
what are the methods to identify antifungal susceptibility testing
|
Broth dilution
Elipsometer Test Disk Method (fluconazole) |
|
|
antifungal susceptibility testing is most useful for?
|
fluconazole and itraconazole
|
|
|
what mould is antifungal suspceptibility testing based on?
|
aspergillus
|
|
|
what is the important thing to remember about azoles when you are doing antifungal susceptibility testing
|
they require growth to work so you will see some growth in the well
|
