fungi Flashcards
Which of the following statements best describes the recognition of bacterial and fungal cell wall components by the innate immune system? A: Bacterial and fungal components are each recognized by different Toll-like receptors. B: Bacterial but not fungal components are recognized by Toll-like receptors. C: Bacterial and fungal components are recognized by common Toll-like receptors. D: Neither bacterial nor fungal components are recognized by Toll-like receptors.
The same Toll-like receptors (TLRs) on phagocytes and dendritic cells recognize bacterial and fungal cell wall components. Recognition triggers IL-12 production and leads to a TH1 response in the adaptive immune system
Which of the following statements best describes the dimorphic fungi? A. Form hyphae at 37°C and yeast at 25°C B. Form conidia at 37°C and hyphae at 25°C C. Form yeast at 37°C and conidia at 25°C D. Form yeast at 37°C and hyphae at 25°C
D. Key point: Dimorphic fungi exist as mold forms in the soil at temps lower than 37C. Spores or condia are formed from the hyphae and are inhaled. Within the lungs and at higher temperatures for in vitro cultures, the spores differentiate into yeasts.
- Match the following antifungal agents with their target. A: Polyenes (e.g. amphotericin B) B: Pyrimidine analogues (e.g. flucytosine) C: Echinocandins (e.g. caspofungin) D: Azoles (e.g. fluconazole) beta-glucan synthesis DNA & protein synthesis Ergosterol synthesis Ergosterol in cell membrane
A: Polyenes target ergosterol in the fungal cell membrane B: Pyrimidine analogues target fungal DNA and protein synthesis C: Echinocandins target b-glucan synthesis D: Azoles target ergosterol synthesis
Cryptococcus yeast
Aspergillus conidia
Histoplasma conidia
. For each of the following, indicate whether the organism is an opportunistic or endemic fungus.
A: Coccicioides immitis ____________________________________
B: Candida albicans ____________________________________
C: Aspergillus fumigatus ____________________________________
D: Histoplasma capsulatum
a. endemic
b. opp
c. opp
d. endemic
Candida albicans germ tube
Aspergillus (could also be Fusarium) septate hyphae
Fusarium banana-shaped conidia
- Match the following geographic regions with the endemic fungal genus:
A. Southwestern US & Latin America
B. Ohio & Mississippi River valleys **
C. Latin America esp. Brazil
D. Central & Southeastern US
- Paracoccidioides*
- Histoplasma*
- Blastomyces*
- Coccidioides*
A. Coccidioides is found in the Southwestern US & Latin America
B. Histoplasma is found in the Ohio & Mississippi River valleys
C. Paracoccidioides is found in Latin America esp. Brazil
D. Blastomyces is found in the Central & Southeastern US
________ is found in the Southwestern US & Latin America
Coccidioides
__________ is found in the Ohio & Mississippi River valleys
Histoplasma
________ is found in Latin America esp. Brazil
Paracoccidioides
____________ is found in the Central & Southeastern US
Blastomyces
What are the 4 endemic mycoses?
- histoplasma
- blastomyces
- coccidioides
- paracoccidioides
_____ and ______ are the most commonly isolated yeast in clinical practice
Candida and Cryptococcus
Most common mold is _________ but ______ and _____ are associated with higher mortality.
aspergillus; Zygomycetes and fusarium
opportunistic infections (5)
CCAMP
- candida albicans
- cryptococcus neoformans
- asperigillus
- mucor and rhisopus
- pneumocystis jiovecli
____ bind ergosterol and from pores in the membrane
Examples: amphotericin B and nystatin
Polyenes
Polyene examples
amphotericin B and nystatin
_________ inhibit ergosterol synthesis
Azoles
Azoles examples
fluconazole, itraconazole, and ketoconazole
_______ beta glucan synthesis inhibitors
Echinocandins
