export_intro to mycology

Question 1

Aside from colonization, what two other ways can fungi cause disease?

Answer 1

Mycotoxins

Allergens

Question 2

Two important characteristics of fungal cells

Answer 2

Cell wall
Membrane sterol composition

These allow for drug targeting, because these differ from our cells

Question 3

Fungal cell wall function

Answer 3

Shape
Rigidity

Strength

Protection from osmotic shock

Question 4

Fungal cell wall composition

Answer 4

Differs from bacteria
Chitin, glucans, mannan

Polysaccharides and proteins

Question 5

Content of fungal cell membrane

Answer 5

Ergosterol, instead of the cholesterol we have

Question 6

Fungal classifications

Answer 6

Yeast
Molds

Dimorphic - both yeast and mold

Question 7

Yeast characteristics

Answer 7

Unicellular

Spherical or ellipsoid shape

Question 8

Yeast reproduction

Answer 8

Budding

Question 9

Pseudohyphae

Answer 9

Results in chains of elongated buds

Budding never actually separates

Question 10

Germ tube

Answer 10

Candida albicans does this diagnostically

Structure during budding, never separates

Question 11

Hyphae

Answer 11

Individual strands of molds

Question 12

Mycelium

Answer 12

Clustered molds, connected by network of hyphae

Question 13

Mold septa

Answer 13

Sometimes hyphae are found with septa - diagnostic of which mold is causing disease

Question 14

Mold reproduction

Answer 14

Sexual (spores)

Asexual (conidia)

Question 15

Types of fungal infections

Answer 15

Superficial mycoses
Cutaneous mycoses

Subcutaneous mycoses

Systemic mycoses

Opportunistic mycoses

Question 16

Superficial mycoses

Answer 16

Colonizations (“infections”) of the outermost layers of skin and hair

Question 17

Cutaneous mycoses

Answer 17

Infection which extends deep into epidermis as well as invasive hair and nail infections
Ringworm, athlete’s foot

Question 18

Subcutaneous mycoses

Answer 18

Infections involving dermis, subcutaneous tissues, muscles, and fascia

Question 19

Systemic mycoses

Answer 19

Infections that originate primarily in the lung, but may spread to any organ in the body
Dimorphic fungi

Question 20

Opportunistic mycoses

Answer 20

Infection associated primarily with immunosuppression

Question 21

Adaptive immunity to fungi

Answer 21

Humoral plays a little role

Cell-mediated is essential

Question 22

Cell wall targets of antifungals

Answer 22

Inhibitors of glucan synthesis and chitin synthesis

Question 23

Cell membrane targets of antifungals

Answer 23

Inhibitors of ergosterol synthesis OR

Direct membrane damage

Question 24

Echiocandins

Answer 24

Drug class that inhibits glucan synthesis

Question 25

Morpholines

Answer 25

Inhibitor of ergosterol synthesis

Question 26

Azoles

Answer 26

Inhibitor of ergosterol synthesis

Question 27

Polyenes

Answer 27

Cause direct cell membrane damage by binding to membrane sterols

Question 28

Allylamines

Answer 28

Inhibitor of ergosterol synthesis

Question 29

Thiocarbamates

Answer 29

Inhibitor of ergosterol synthesis

Question 30

Polyene drug example

Answer 30

Amphotericin B

Question 31

Echinocandin usages

Answer 31

Inhibit beta-glucan, so highly selective | Primarily for Candida and Aspergillus

Question 32

Best diagnostic tool for fungi

Answer 32

Direct visualization of fungal elements

Question 33

KOH preparation

Answer 33

Used to examine hair, nails, fluids, etc. Can observe structures such as hyphae The tissue will dissolve faster than fungal structures due to their cell walls Dyes can enhance visualization

Question 34

Where do stains bind in fungal samples?

Answer 34

Carbohydrate cell wall

Question 35

How do ALL fungi stain?

Answer 35

Gram positive!

Question 36

Germ tube test can identify?

Answer 36

Candida albicans

Question 37

India ink stain can identify?

Answer 37

Cryptococcus neoformans