Introduction Flashcards
define mycology
the study of fungus
what is fungus
chlorophyll free unicellular or multicellular Eukaryotic organism which reproduce by sexually or asexually
what is mycoses
fungal infections are called
structures of fungal cell
cell wall
cell membrane
cytoplasm
nucleus
capsule
cell wall components
Chitin,Glucan,Mannan
structural and enzymatic proteins
Glycoproteins
functions of cell wall
protection
rigidity and strength
shape
reproduction
cell membrane contents
Ergosterol
Zymosterol
is capsule essential?
No,its non essential
which fungus has capsule?
Cryptococcus neoformans
does histoplasma capsulatum posses capsule?
No
difference between fungal and bacterial cell wall
Chitin - Peptidoglycan
beneficial effect of fungus
drugs
edible mushroom
culture foods
bio remediation
and environmental benefits
what are the drugs made by fungus
antibiotics
(penicillin g)
antifungal
(Griseofulvin)
immunosuppressants
(Ciclosporin)
statins
(Mevastatin,Lovastatin)
source of penicillin
penicillium chrysogenum
source of Griseofulvin
penicillium chrysogenum
what are the edible mushrooms
Agaricus bisporus - salads,soups
Molds - cheese production
what are the fungal toxins
Amnitin,Phalloidin(Amanita Mushroom) - Liver necrosis(by inhibiting RNS polymerase)
Aflatoxin(Aspergillus flavus) - liver cancer(produce epoxide and cause mutation p53 gene)
Pathogenesis
1.inflammation
(Formation of granuloma
, acute suppuration)
2.mycotoxicoses
3.allergy
which immunity gives protection against Fungus?
Cell mediated immunity
does acquired immunity gives protection against fungus?
No
which antibodies are produced against fungus?
IgG and IgM
why bacteria cannot grow in fungal culture?
1.low pH
2.Antibacterial agent(penicillin,chloramphenicol,Streptomycin,Cycloheximide)
what are the specimen
skin scrapping
nail clipping
hair plucking
swabs
aspirated pus
Biopsy material
What are the process of lab diagnosis
Direct microscopic examination
isolation from culture
serology
PCR
mass spectrometry
How specimen is treated during microscopic examination
Using 10% KOH to dissolve tissue material like ( keratin epithelial cells leukocytes debris) or staining with special fungal stains.
Calcofluor white
Methenamine silver stain
What is the culture media
Sabouraud’s dextrose agar
Temperature in culture media
25 degree Celsius and 37 degree Celsius for 2 to 3 weeks in Aerobic condition
What are the serological test
CFT
latex aglutination test
Are Serological test reliable?
Nope.
1.Normally antibody sir present due to normal flora
2. immunity against fungal diseases cell mediated
What are the process of fungal reproduction
Sexual and asexual
What are the sexual spores
Zygospore
Ascospores
Basidiospores
What are the asexual spores
Chlamydospores
Arthrospores
Blastospores
Sporangiospores
Zygospore
Single large spore with thick walls
(Rhizopus,Mucor)
Ascospores
Formed in a sac
(Histoplasma,Microsporum)
Basidiospores
Externally on tip of a pedestal called basidium.
Cryptococcus
Chlamydospores
One cell analysis and specialise to form a spore
Rounded, thick walled, quiet resistant
Candida albicans
Arthrospores
Arise by fragmentation of the ends of hyphae
Coccidioides immitis
Blastospores
Formed by budding process
Yeasts
Sporangiospores
Formed within a sac on a stalk by molds
rhizopus and mucor
Fungi imperfect
Do not form sexual spore
Morphological classification
YEast
yEast like fungus
mold
diamorphic fungus
Yeast
Cryptococcus neoformans
Yeast like fungus
Candida albicans
Molds
Rhinosporidium seeberi
Dermatophytes
Dimorphic fungus
Histoplasma capsulatum
Coccidioides immitis
Blastomyces dermatitidis
Para-coccidioides brasiliensis
Clinical classification
Superficial cutaneous subcutaneous systemic opportunistic
Superficial
Malassezia furfur
Hortaea werneckii
Piedraia hortae
Trichosporon species
Cutaneous
Dermatophytes, candida
Subcutaneous
Sporothrix schenckii
Phialophora verrucosa
Madruella mycetomatis
Exophiala ,Bipolaris
Systemic
Histoplasma capsulatum
Coccidioides immitis
Blastomyces dermatitis
Para-coccidioides brasiliensis
Opportunistic
Candida albicans
Cryptococcus neoformans
Aspergillus fumigatus
Penicillium marneffeii
Mucor
According to method of reproduction
Sexual
Ascomycotina
Basidiomycotina
Zygomycotina
#asexual
Deuteromycotina
Yeast Vs molds
Uni - multi
Spherical/elliptical - filaments
Budding/binary fission - sexual/asexual
Dimorphic forms
Mold 22 to 25 degree Celsius room temperature
Yeast 37 degree Celsius host tissue
Systemic antifungal
Amphotericin b
Azoles ( fluconazole ,ketoconazol, itraconazole, voriconazol,posaconazol)
Echinocandins (Caspofungin,Micafungin)
Flucytosin
Griseofulvin
Topical use skin only
Azoles (Clotrimazole, Miconazole)
Terbinafine
Tolnaftate
Nystatin
Systemic cell membrane inhibitor
Amphotericin B - binds to ergosterol and disrupts fungal cell membrane
Azoles - inhibit synthesis of ergosterol
Systemic cell wall inhibitors
Echinocandins(Caspofungin, Micafungin)-inhibit synthesis of d glucan
Inhibit DNA synthesis
Flucytosin - convert to fluorouracic and inhibit thymidine synthetase
Disrupts mitotic spindle
Griseofulvin - binding to tubulin
Topical cell membrane inhibitor
Azoles (Clotrimazole, Miconazole)
Terbinafine
Tolnaftate
All inhibit ergosterol synthesis
Nystatin -bind ergosterol and disrupts membrane
Amphotericin B
Bind and disrupts
Azole
Inhibit synthesis
Terbinafine
Inhibit synthesis
Nystatin
Bind and disrupt
Caspofungin
Inhibit synthesis of D glucan