Intro to Fungi Flashcards
fungi are _______ organisms and have a cell membrane that consists of ________
eukaryotic, ergosterol
what are most fungi’s classified by w/regards to their oqygen intake
strict aerobes, or facultative anaeorbes
funci that typically become pathogenic have what virulence factor
capable of living/growing at high temps (37 degrees C)
a unicellular fungi is referred to as a ________, whereas a multicellular fungi is called a ?
yeast, filamentous mold
a mass of hyphae in a mold is known as ?
mycelium
the cross walls in a mold are called _______, where as a mold without crosswalls is called ____?
septae, coenocytic
what does dimorphism mean
a pathogenic fungi that can exist as molds and yeast
what typically induces phase change in dimorphism
temperature
which stage of dimorphism tends to be more pathogenic and why ? what is the exception to this rule
yeasts tend to be more pathogenic because they can survive at high temperature (37)
-EXCEPTION - Candida is a mold form pathogen
more research on fungi is being conducted today for what 3 reasons
- people die from fungal infections
- profitable antifungal drugs
- genome sequencing of fungi
fungi that become pathogenic can be encountered by what 2 broad mechanisms
- incidental environmental contact
- normal flora (yeasts)
what are the main 2 host responses to eliminate fungal infections
- neutrophils (phagocytosis)
- t cell mediated immunity
there are 3 types of mycoses, what are they
1 - endemic
2 - oppurtunistic
3 - Skin rashes (superficial cutaneous, or subcutaneous)
what are the 3 endemic fungal pathogens
histoplasmosis
blastomycosis
coccidiomycosis
what type of mycoses usually cause infections in clusters ?
endemic fungal pathogens
where is the “histo belt” for where histoplasmosos typically affects people
mid-southeastern US
what endemic pathogen causes reticuloendothelial system infection
histoplasmosis
where does endemic pathogen blastomycosis typically affect
Missisippi river vally and southeastern states
histoplasmosis and blastomycosis both cause what type of infections
- pulmonary (pneumonia)
- disseminated infections (skin lesions)
the virulence of both histoplsamosis and blastomycosis is directly related due to the transformation to the yeast phase triggered by ?
warmer temperatures of the human body
what is the endemic pathogen coccidiomycosis host range
dry southwest
what are spherules and what endemic pathogen has them as a virulence factor
large ball of hundreds of endospores making the pathogen hard to kill
-coccidiomycosis
what endemic pathogen results in desert rheumatism or valley fever
coccidiomycosis
which endemic pathogen has the ability to cause disseminated infections, and chronic meningitis ?
coccidiomycosis
treatment of endemic pathogens both have mechanisms that attack what specif part of fungal pathogens
ergosterol component of cell membranes
-cuz its specific to fungi so wont affect host
what is the difference b/w polyenes and azoles as treatment for endemic pathogens
polyenes - form channels in ergosterol
azoles - mess up ergosterol synthesis
oppurtunistic fungal infections are NOT true ______ ?
pathogens
who do oppurtunistic mycoses affect
immunocomprimised patients
what is the most frequent oppurtunistic fungal pathogen ? and what is unique about this compared to other fungi ?
Candida albicans
-pathogenic in mycelial/mold form
how is candida albicans aquired by the host
its normal endogenous flora, only affects in immunocomprimised patients
what are the symptoms of candidiasis
thrush (white milky lesions)
-diaper rash
what are the 5 oppurtunistic pathogens
candida cryptococcosis aspergillis mucormycosis pneumocystis
which oppurtunistic pathogen produces melanin as a virulence factor which increases cell wall strength
cryptococcis
in general, fungal pathogens that are inhaled cause what type of infection
pulmonary infection (pneumonia)
what is the newest emerging oppurtunistic pathogen in the northwest states of the US
cryptococcus
which oppurtunistic pathogen is known to be ubiquitous, but not part of the normal flora
aspergillis
what are the 2 oppurtunistic pathogens found in normal skin flora
candida albicans and cryptococcus
what oppurtunistic pathogen affects the lungs
aspergillis
what opppurtunistic pathogen causes rhinocerebral form (diabetes patients) or disseminated pulmonary lesions
mucormycosis
which oppurtunistic pathogen is confined ONLY to pulmonary spaces and cannot become disseminated
pneumocystis
dermatophytes are characterized as what type of mycoses
rash causing fungi or superficial cutaneous
seborrheic dermatitis and tinea versicolor are both the main outcomes of what type of mycosal pathogen
rash causing fungi or superficial cutaneous
T/F dermatophytes are part of the normal skin flora
False
what are the common name of dermatophyte skin infections
ringworm, athletes foot, jock itch, swamp ass
what type of mycoses are known as “mycoses of immplantation”
subcutaneous mycoses (rash causing mycoses)
what are the 2 types of rash causing mycosis
superficial cutaneous
subcutaneous
most subcutaneous mycoses occur in what regions of the world
tropical areas
What is the difference b/w antifungals allylamines and echinocandins
allylamines - blocks ergosterol synthesis
erchinocandins - block cell wall (NEW)
