Term
Distinguish between the following categories of fungi.
- Saprobes
- Symbionts
- Commensals
- Parasites |
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Definition
Saprobes: live on dead/decaying matter
Symbionts - live together with mutual adv.
Commensals - live together; one benefits and the other may or may not benefit
Parasites - one benefits and the other does not benefit or is harmed |
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Term
| Distinguish between yeast and mold forms of fungal growth. |
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Definition
yeast: unicellular, multiply by budding off of blastoconidia
mold: multicellular, growth by septate/aseptate hyphae |
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Term
| Distinguish between pseudohyphae and true hyphae. |
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Definition
| pseudohyphae: pinched; less rigid cell walls |
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Term
What are the arrows pointing to in the following true hyphae?
[image] |
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Definition
| arthroconidia and disjunctor cell (space) |
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Term
| Distinguish between an anamorph and a telemorph. Which one is found in clinical specimens and which one occurs in the laboratory? |
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Definition
anamorph: asexual conidia/spore producer; in clinical specimens
telemorph: sexual spore producer; occurs in laboratory under special conditions |
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Term
Name the 2 anamorphs and associated structures of the figure below.
[image] |
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Definition
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Term
| In the case of thermally dimorphic fungi, which form of fungal growth occurs in infected tissue and which form occurs environmentally/in the lab? |
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Definition
Yeast: in infected tissue; at 37C
Mold: environmental reservoir/in lab; at 25C |
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Term
Which categry of mycoses are described below?
- lesions limited to very superficial surfaces of skin and hair; destroy keratin, cosmetic importance only; person-to-person transmission or via contaminated objects |
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Definition
| superficial cutaneous mycoses - dermatophytes |
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Term
What category of systemic fungal mycoses are described below?
A. specific geographic location; thermally dimorphic
B. immunocompromised hosts (i.e. with catheters or implanted devices); primarily lung infection with dissemination elsewhere |
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Definition
A. endemic mycoses
B. opportunistic mycoses |
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Term
| To what component of the cell wall does the flourescent stain of calcoflour white stain bind? |
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Definition
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Term
Describe the following components of the polyene, Amphotericin B.
- mechanism of action
- toxicity
- pharmacokinetics
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Definition
- damages cell membrane by binding ergosterol
- nephrotoxicity
- slow degradation |
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Term
Describe the following components of the azole, Voriconazole.
- mechanism of action
- toxicitypharmacokinetics |
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Definition
- decreases synthesis of ergosterol
- minimal toxicity
- hepatic metabolism so necessitates liver function tests |
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Term
Describe the following components of the echinocandins.
- mechanism of action
- toxicity |
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Definition
- decreases cell wall integrity
- liver function monitoring, otherwise little hepatotoxicty |
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Term
Describe the following components of the antimetabolites.
- mechanism of action
- resistance
- toxicity |
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Definition
- inhibits DNA, RNA, and cell wall synthesis
- bugs become resistant over time so used in combination with amphotericin B cause
- hepatotoxicity, bone marrow suppression, and GI intolerance |
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Term
What classification do the following mycoses belong to?
- lesions of outermost skin and appendages; no host immune response; nondestrictive and asymptomatic; cosmetic concern |
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Definition
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Term
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Definition
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Term
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Definition
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Term
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Definition
| tinea unguium, caused by Trichopyton rubrum |
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Term
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Definition
| tinea barbae; Trichophyton verrucosum |
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Term
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Definition
| tinea capitis; Microsporum canis |
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Term
What classification of mycoses does the following description belong to?
- contamination reaches subcutaneous tissue via traumatic inocculation; occasional spread to lymph nodes but dissemination is rare. |
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Definition
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Term
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Definition
| lymphocutaneous spororichosis, Sporothrix schenckii |
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Term
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Definition
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Term
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Definition
| subcutaneous zygomycosis, Basidibolus ranarum |
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Term
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Definition
| subcutaneous zygomycosis, Conidiobolus coronatus |
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Term
What classification of mycoses do the following characteristics belong to?
- infects healthy and immunocompromised hosts; penetrates into deep viscera; |
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Definition
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Term
What systemic mycoses does the following "coin lesion" in the lung characteristic of?
[image] |
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Definition
| histoplasmosis, Histoplasma capsulatum |
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Term
Which category of mycoses do the following characteristics belong to?
- infection in immunocompromised hosts |
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Definition
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Term
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Definition
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Term
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Definition
| pneumocystosis; Pneumocystic jirovecii |
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Term
| Distinguish between hyaline and dematiaceous molds. |
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Definition
hyaline: pale or white grain (e.g. Aspergillus spp.)
demataiceous: naturally pigented (cause subcutaneous phaeohyphomycosis) |
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