Mycology Flashcards
Mycology is the study of fungi
Relatively novel field in medicine
Mycoses:
Mycotoxins:
Mytoxicosis:
Fungi infections
Toxins produces by fungi eg aflatoxin of Aspergillus flavus
Fungi intoxification
Fungi are heterotrophic eukaryotes
Morphologically categorized into ____ &____
They are saprophytic organisms
Heterotrophic
yeast (single-celled) and filamentous (mold) forms.
Fungi are like mammalian cells, that is, they are eukaryotic but their cell membranes differ in that they contain _____, while mammalian cells contain cholesterol.
Ergosterol
Over _____ species of fungi are estimated to be in existence with only _____ species accounting for disease in human
5 million
~300
fungi cell wall is made up of _____,____,____& ____
Size-diameter
Chitin
Mannan
Or both
Beta glucans
4 um——-1um
Fungi are thermal ______
Dimorphic
The cell membrane contains ______ which is absent in bacteria asll (cholesterol)
Ergosterol
Ergosterol is the site of action of antifungal drugs,
Eg
amphtericin B
azole group
There are 4 fungi and 2 endemic dimorphic main fungal pathogens responsible for the majority cases of serious fungal disease.
These are
Aspergillus,
Candida,
Cryptococcus species,
Pneumocystis jirovecii,
endemic dimorphic fungi such as
Histoplasma capsulatum
Talaromyces marneffei
3 fungi are always lethal unless diagnosed and treated early and correctly.
Cryptococcal meningitis,
pneumocystis pneumonia,
disseminated histoplasmosis
Most fungi are _____, some are ______, but none are _______.
Obligatory Aerobes
Facultative anaerobes
Obligatory Anaerobes
All fungi require a performed ______ ______ ______–association with decaying matter.
Most are saprophytic
organic source of carbon
_____ is the environment except for _______ ___which is part normal flora of humans
Natural habitat
Candida spp
Fungi causes diseases primarily in humans if they are ______ or ______
immunosuppressed OR the fungal spores (load/burden) is much
6 Common immunosuppression that predispose to mycoses are ?
diabetes,
HIV/AIDS,
long term steroid use,
cancers,
cancer treatments,
stem cell and solid organ transplant
Etc
Fungi morphology
Filamentous fungi (molds)
Yeasts
Yeast-like fungi
Dimorphic fungi
The basic morphological elements of filamentous fungi are long branching filaments or ____, which intertwine to produce a mass of _____ or ______
Hyphae
Filaments or mycelium
Colonies are strongly adherent to the medium and unlike most bacterial colonies cannot be __________
Hyphae can be____ or ____
Their colony on ____ aids their diagnosis by their appearance and pigments produced
Emulsified in water
septate or non septate
Agar
Yeast fungi occur in the form of round or oval bodies which reproduce by the formation of ____ known as_____.
They are also called budding yeast, with _____ ______attached
Yeasts colonies resemble bacterial colonies in
______&_______
Buds
Blastospores
Daughter cells
appearance and in consistency.
Dimorphic fungi are ______ in the environment (saprophytic phase) 25 – 270C.
______ in human body (parasitic/pathologic phase) 370C.
Molds
Yeast
Examples of Dimorphic fungi
Histoplasma carpsulatum
Blastomyces
Mycoses can occur in 4 ways these are
Superficial
Subcutaneous
Systemic
Opportunistic
