Term
| Griseofulvin Characteristics |
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Definition
natural product
oral tx for treating dermatophytes |
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Term
| Griseofulvin Mechanism of Action |
|
Definition
inhibits growth by disrupting mitotic spindle structure
normal mitosis cannot proceed
concentration in newly formed cells of skin, hair, nails
stops infection from spreading
fungi are shed as infected hair, skin, nails are replaced |
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Term
|
Definition
natural product from some streptomyces species
Amphotericin B and Nystatin |
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Term
| Polyenes Mechanism of Action |
|
Definition
binds to ergosterol in fungal membrane
distorts membrane which alters permeability
causes leakage of ions |
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Term
| Amphotericin B Characteristics |
|
Definition
from streptomyces nodosus
used IV to treat deep-seeded fungal infections |
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Term
| Amphotericin B Mechanism of Action |
|
Definition
several molecules insert into cytoplasmic membrane of fungi
forms cylindrical channel that pentrates membrane
pore causes leakage from cell
must cross cell wall to access membrane |
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Term
| Amphotericin B Adverse Reactions |
|
Definition
nephrotoxic
binds to other sterols (cholesterol) |
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Term
| Amphotericin B Resistance |
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Definition
| alterations in membrane sterol composition creates resistance |
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Term
| Flucytosine Characteristics |
|
Definition
originally created as anticancer
aka 5-flurocytosine or 5-FC
inhibits growth of Candida and Cryptococcus
used for treating fungal meningitis |
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Term
| Flucytosine Mechanism of Action |
|
Definition
disrupts DNA and RNA synthesis to inhibit fungal growth by two mechanisms
1)enters cell and is converted inside the cell
replaces uracil in pyrimidine pool
distorts normal RNA structure
2) enters cell and is converted
competitively inhibits thymidylate synthetase which makes thymidine for DNA synthesis |
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Term
| Flucytosine Adverse Reactions |
|
Definition
cannot be used directly as antifungal
not taken up by fungal cells and is toxic to mammalian cells |
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Term
|
Definition
secondary resistance: develop resistance during treatment
decreased permeability, deficiency in enzymes to convert, synthesis of metabolites to compete?
develops more rapidly when used alone
use with amphotericin B |
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Term
|
Definition
synthetic compounds
lower toxicity and broad spectrum
systemic and topical drugs |
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Term
| Azoles Mechanism of Action |
|
Definition
interfere with ergosterol biosynthesis
depletes ergosterol to alter plasma membrane structure
damage of membrane makes cell susceptible for other damage
inhibits fungal growth |
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Term
|
Definition
| develops through long-term use |
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Term
| Imidazole Characteristics |
|
Definition
Ketoconazole
oral or topical |
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Term
| Itraconazole Characteristics |
|
Definition
broad range of antifungal activity
treats dermatophytes |
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Term
| Fluconazole Characteristics |
|
Definition
lower toxicity
penetrates CSF
treats Candida and Cryptococcus
ineffective against Aspergillus |
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Term
| Voriconazole Characteristics |
|
Definition
| effective against Aspergillus |
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Term
| Echinocandins Mechanism of Action |
|
Definition
| inhibits B1,3-glucan synthesis in fungal cell wall |
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Term
| Echinocandins Characteristics |
|
Definition
Caspofungin, Micafungin, Anidulafungin
treats Candida and Aspergillus if doesn't respond to other agents |
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