Unit 2 - Week 3 - Greenblatt 3, Stein 6 and 7

Question 1

What are the four major categories of fungal infection (mycosis)?

Answer 1

1. Opportunistic
2. Superficial
3. Subcutaneous
4. Systemic

Question 2

True or False: Superficial mycosis requires thermal dimorphism.

Answer 2

False, often growing on cool exterior as hyphae. Subcutaneous involves thermal dimorphism

Question 3

How would you treat a superficial mycosis infection?

Answer 3

1. Topical azoles

2. If necessary, oral griseofulvin

Question 4

How would you treat subcutaneous mycosis infection?

Answer 4

Oral azoles, and if serious, a short course of Amphotericin B and local surgery

Question 5

Give an example of a subcutaneous fungal infection?

Answer 5

Sporotrichosis, treated with oral itraconazole

Question 6

Coccidiodes, Histoplasma and Blastomyces are:

Answer 6

systemis fungal infections, often mimic TB

Question 7

What is the only systemic fungal infection that has a distinct spherule shape in human tissue?

Answer 7

Coccidiodes immitis

Question 8

How are the systemic fungal infections spread?

Answer 8

ARTHROSPORES are carried on the wind and inhaled.

Question 9

How do you diagnose a coccidiodes infection?

Answer 9

PPD w/ coccidioidin or spherulin:
(+) with exposed w/ cleared or contained infections
(-) if unexposed OR disseminated infection (immunosuppressed)

Question 10

True or False: Coccidiodes culture on Sabouraud’s agar produces contagious hyphae.

Answer 10

TRUE

Question 11

What is the treatment for disseminated coccidiodes?

Answer 11

Amphotericin B or itraconazole

Question 12

Cryptococcus is best known for what infection?

Answer 12

Fungal meningitis

Question 13

Where is crytptococcus found?

Answer 13

Pidgeon droppings

Question 14

How would you diagnose a cryptococcus infection?

Answer 14

CSF and India ink to see yeast with wide capsule
OR periodic acid-Schiff mucicarmine
OR methenamine silver

Question 15

AIDS patients require _____ for long-term suppression of crytptococcus infection?

Answer 15

Fluconazole

Question 16

Dermatophytoses: ringworm and tinea are examples of:

Answer 16

superficial mycoses

Question 17

How do you diagnose superficial mycoses?

Answer 17

1. PPD w/ trichophytin
2. Microscopic exam, KOH to break down skin cells, examine remains for yphae/spores
3. Culture on Sabouraud’s agar

Question 18

Sporotrucjosis is caused by:

Answer 18

Sporothrix spp

Question 19

How does cryptococcosis present?

Answer 19

Only in immunocomprimised, meningitis, skin nodules and/or pulmonary symptoms.

Question 20

Cultures of sporotrichosis looks like:

Answer 20

daisies

Question 21

Erythema nodosum can be found in:

Answer 21

coccidioides infection

Question 22

What immune response can make coccidioides infection fatal?

Answer 22

Immune anergy, like apathy

Question 23

Why is meningitis harder to discern in crytptococcal infection?

Answer 23

Meningitis is subacute, so telltale symptoms may not be present, but people are sicker than they look

Question 24

Use of flucytosine in cryptoccal infection is only useful in combination with:

Answer 24

Amphotericin B

Question 25

What are the best known microdeletion syndromes?

Answer 25

Prader-Willi syndrome | Angelman syndrom

Question 26

What are the clinical characteristics of Prader-Willi syndrome?

Answer 26

``` Overeating Bad temper Developmental delay Hypogonadism Small hands and feet ```

Question 27

What are the clinical features of Angelman syndrome?

Answer 27

``` Severe mental retardation Inappropriate syndrome Hyperactivity Short Microcephaly Siezures Ataxia ```

Question 28

For PWS, if a deletion is present, it is on:

Answer 28

chromosome 15 from the father

Question 29

For AS, if a deletion is present, it is on:

Answer 29

chromosome 15 from the mother

Question 30

Uniparental disomy (UPD) means:

Answer 30

A child inherited 2 alleles from the same parent

Question 31

For PWS, if no deletion is present, UPD is seen:

Answer 31

from the mother

Question 32

For AS, if no deletion is present, UPD is seed:

Answer 32

from the father

Question 33

True or False: UPD cannot be detected by standard karyotype analysis.

Answer 33

True, because the homologs will look alike

Question 34

What is the best way to determine UPD?

Answer 34

Molecular probe studies | Microarray

Question 35

The expected pattern or chromosome inheritance is 1 chromosome from each parent, called:

Answer 35

Biparental heterodisomy

Question 36

What is uniparental isodisomy?

Answer 36

2 copies of the same chromosome from 1 parent

Question 37

UPD usually results from:

Answer 37

Meiotic nondisjunction errors

Question 38

Uniprental isodisomy is a form of:

Answer 38

Rescue, because most monosomies are not compatible with life

Question 39

What is Imprinting?

Answer 39

The differential modification of the maternal and paternal genetic contributions to the zygote resulting in the differential expression of parental alleles during development and in the adult.

Question 40

Define methylation:

Answer 40

Addition a methyl group to a cytosine residue in the DNA

Question 41

What is the imprinting cause of PWS?

Answer 41

The complement is comprised of one chromosome from dad and one from mom, but the paternal chromosome has a maternal imprint resulting in functionally only maternal alleles.

Question 42

What is the imprinting cause of AS?

Answer 42

The complement is comprised of one chromosome from dad and one from mom, but the maternal chromosome has a paternal imprint resulting in functionally only paternalalleles.

Question 43

What disease is associated with UBE3A inactivity?

Answer 43

Angelman syndrome

Question 44

Define Epigenetics:

Answer 44

The study of heritable changes in gene function that are not caused by change in DNA sequence

Question 45

Epigenetic modifications include:

Answer 45

1. chromatin remodeling 2. DNA methylation 3. histone modification

Question 46

Downregulation of miRNA caused by ____ at the miRNA promoters is reported in a number of tumors:

Answer 46

hypermethylation

Question 47

miR-21 is upregulated in:

Answer 47

breast cancer

Question 48

Rett syndrome is linked to mutations in the:

Answer 48

MECP2 TF (plus X-inactivation)

Question 49

Why is Rett syndrome almost exclusively female?

Answer 49

Because males that lack MECP2 on their X do not survive

Question 50

What is Pharmacogenetics?

Answer 50

Heritable variation to inter-individual variation in drug responses

Question 51

What is Pharmacogenomics?

Answer 51

The field of new drug development based on our rapidly increasing knowledge of the human genome

Question 52

Cytochrome P450 is a family of genes known for:

Answer 52

Its involvement in drug metabolism.

Question 53

What are the classes of drug function metabolism?

Answer 53

1. Ultra 2. Extensive 3. Intermediate 4. Poor

Question 54

What is an ultra metabolizer?

Answer 54

A person has duplicate copies of the alleles involved in drug metabolism, and therefore the drug being given is too rapidly degraded to have an effect.

Question 55

Provide an example of a drug that shows significant carying metabolism in the population.

Answer 55

6-mercaptopurine for leukemia

Question 56

The synthetic form of coumadin is:

Answer 56

warfarin

Question 57

What is the MOA of warfarin?

Answer 57

It inhibits the enzyme epoxide reductase resulting in the inhibition of Vitamin K metabolism, which reduces clots.

Question 58

True or False: DNA Microarray can be useful at identifying microduplication.

Answer 58

True

Question 59

What is the more politically correct term for consanguinity?

Answer 59

Identity by descent

Question 60

When the total regions of homozygosity (ROH) exceed 5% in an individual, the cause it usually:

Answer 60

IBD - inbred populations, isolated populations, specific ethnic groups