test #8 3.21 Flashcards Preview

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Flashcards in test #8 3.21 Deck (172)
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1

kinesin

MT-associated motor protein involved w/ anterograde transport of intracellular vessicles / organelles towards + end (DISTANT from nucleus)

2

microvilli contains..

actin thin filaments (NOT microtubules)

3

isotype class switching occurs via..

modification of immunoglobulin GENOME (DNA recombinase & enzymes that excise loops of DNA not being used)

4

hyper IgM syndrome

mutation in enzymes responsible for isotype switching in B cell, or CD40L in T cells. rx: IVIG

5

what is present in colostrum

initial maternal milk, contains IgA dimers, joined at Fc region w/ J chain

6

most common B-cell related deficiency?

selective IgA deficiency

7

clinical presentation of hyperIgM syndrome (2)

(1) lymphoid hyperplasia and (2) recurrent sinopulmonary infections

8

amino acid attachment site on tRNA

3'

9

what is contained in the t(psi)C arm (near 3' end) of tRNA and D loop (near 5' end)?

t(psi)c arm has 3 nucleotide sequence present in all tRNA molecules (ribothymidine, pseudouridine, and cytosine). D loop has unpaired bases

10

5' end of tRNA serves to..

composed of terminal guanosine. does not participate in amino acid or mRNA binding.

11

what is the smallest subtype of cellular RNA?

tRNA

12

sensitivity

of the people who have disease, how many will test positive (a/a+c)

13

specificity

of the people without disease, how many will test negative (d/b+d)

14

false positive

(1-specificity) x no. people w/o disease

15

false negative

(1-sensitivity) x no. people w/ disease

16

alkaptonuria

benign disorder of tyrosine metabolism. autosomal recessive deficiency of homogentisate oxidase (blocked metabolism of phenylalanine and tyrosine at level of homogentisate), preventing conversion of tyrosine to fumarate. homogentisic acid accummulates and excreted in urine. turns black if allowed to stand & oxidize. homogentisic acid deposition in collagen of CT, tendon, and cartilage --> ochronosis --> blue-black pigmentation most evident on ears, nose, and cheeks

17

black urine on standing

alkaptonuria and acute intermittent porphyria (?)

18

alkaptonuria clinical presentation

urine turns black when standing. blue-black pigmentation most evident on ears, nose, and cheeks (homogentisic acid deposition in collagen of CT, tendon, and cartilate, causing "ochronosis"

19

phenylketonuria (PKU)

defect in phenylalanine hydroxylase (smaller %age have defect in dihydrobiopterin reductase deficiency). impaired conversion of phenylalanine to tyrosine.

20

cysteine synthesis

sulfur-containing amino acid synthesized from amino acid serine and homocysteine (which is derived from methionine)

21

histidine degradation

histidine --> FIGLU (formiminoglutamate) ---subsequent rxn--> transfer one carbon from FIGLU to THF, then release NH4+ and glutamate in the process. glutamate subsequently deaminated to form an alpha-ketoglutarate that enters TCA for further metabolism

22

DOPA synthesis

phenylalanine ----phenylalanine hydroxylase or dihydrobiopterin reductase w/ BH4 --> BH2 conversion----> tyrosine ----tyrosine hydroxylase--> DOPA

23

how is whole blood prepared prior to storage? what must be considered following massive transfusions?

mixed w/ solutions containing citrate anticoagulant. will be in packed cells. massive transfusions of >5-6 L of blood (total body blood volume) in 24 hours --> chelate serum calcium --> hypocalcemia --> paraesthesia

24

rx for acute mania (2)

(1) mood stabilizer (lithium, valproate, carbamazepine) and (2) atypical antipsychotic (olanzapine)

25

SSRI on mania?

known to precipitate manic episodes, contraindicated!

26

buproprione

mixed dopamine and norepinephrine reuptake inhibitor (DNRI) and nicotinic agonism. rx: depression and smoking addiction. risk of exacerbating mania

27

parvovirus B19 infxn vs. rubella

parvovirus B19: low-grade fever 7-10 days, bright-red "slapped" cheeks, followed by lacy rash on trunk and extremities. rubella: mild fever, discrete maculopapular rash from head to trunk/extremities.

28

parvovirus B19 in kids vs. adults

kids: low-grade fever --> slapped cheeks FACE --> lacy rash on EXTREMEITIES. adults: symmetrical peripheral arthropathy on fingers, wrist, and ankles

29

rubella characterestic.

characteristic: occipital and posterior cervical lymphadenopathy. have mild fever and discrete maculopapular rash from HEAD INFERIORLY that resolves in 3-5 days.

30

scarlet fever presentation

fever, sore throat, diffuse erythematous rash w/ numerous small papules (sandpaper-like)