Primer 16 Flashcards
Which Abx are assc with these ADRs?
- teeth discoloration
- tendonitis/ cartilage damage
- red man syndrome
- grey baby syndrome
- nephrotox/ ototox
- pseudomembranous colitis
- teeth discoloration: tetracyclines
- tendonitis/ cartilage damage: FQs
- red man syndrome: vanc
- grey baby syndrome: chloramphenicol
- nephrotox/ ototox: aminoglycosides
- pseudomembranous colitis: metronidazole, clinda
- but can really be caused by most any Abx, clinda/ metro are just most common
Five classes of Abx that can be given to pregnant patients ?
- penicillins (remember, Pen G is given in gases of strep agalactiae “GBS” infections)
- nitrofurantoin
- macrolides
- metronidazole (2-3 weeks)
What are the three borders of hesselbach’s triangle?
Why should we care about this?
- inferior epigastric
- lateral rectus abdominis
- inguinal ligament
- site of direct inguinal hernia
What is a nucleosome?
H1 histone?
Chromatine?
- nucleosome: 8 histones + DNA wrapped around them (twice) (+ Lys/ Arg from histone binds - phosphate in DNA)
- H1 histone connects adjacent nucelosomes
- chromatin- set of multiple nucleosomes
What DNA bases are Purines?
What are their carbon sources?
What are their nitrogen sources?
- pure As Gold (A,G= purines)
- carbon sources: CO2, glycine, THF
- Without THF, your kid is gonna be a PURE(ine) disaster
- nitrogen sources: glutamine, aspartate
What DNA/ RNA bases are pyrimidines?
What are their carbon sources?
What are their nitrogen sources?
- thymidine, uracil, cytosine (ones that aren’t pure As Gold)
- carbon: CO3; glutamine
- nitrogen: aspartate
- also need ATP and carbamoyl phosphate
Compare carbamoyl phosphate 1 &2:
type 1: urea cycle
type 2: rate limiting enzyme for pyrimidine synthesis
type 1 is in mitochondria, type 2 is in cytosol
type 1 accepts nitrogen from ammonia, type 2 accepts nitrogen from glutamine
UMP Synthase:
action of enzyme
clinical relevance?
pyrimidine synthesis
orotic acid –> UMP
lack of enzymes= orotic aciduria
(acid in urine, megaloblastic anemia, no changes in ammonia, AR disease)
Ribonucleotide reductase :
action of enzyme
clinical relevance ?
Pyrimidine synthesis
UDP –> dUDP
targeted by hydroxyurea, drug for sickle cell
Thymidylate synthase:
action of enzyme?
clinical relevance?
pyrimidine synthesis
dUMP –> dTMP
targeted by 5FU chemotherapy drug
Dihydrofolate reductase:
action of enzyme?
clinical relevance?
- converts DHF –> THF in pyrimidine synthesis pathway regenerates THF for purine synthesis
- inhibited by trimethoprim & methotrexate
- Trimethoprim is NOT an antibiotic that is safe in pregnancy because it messes up THF synthesis meaning the baby will be PURE(ley) f*cked.
- Lack of this enzyme would also= megaloblastic anemia secondary to folate deficiency
glutamine PRPP amidotransferase:
action of enzyme
clinical relevance ?
PRPP –> IMP in purine synthesis; RLS*
targeted by 6-mercaptoPURINE in chemotherapy
(mercaptoPURINE inhibits RLS of PURINE synthesis)
IMP dehydrogenase?
Action of enzyme?
clinical relevance?
IMP –> GMP in purine synthesis
targeted by immunosuppressant: mycoPhenolate
(P for Purine synthesis inhibitor)
Symptoms of ornithine transcarbamylase deficiency?
megaloblastic anemia
orotic aciduria
increased urinary ammonia levels!, not seen in orotic aciduria, or UMP synthase deficiency!!!!
Xanthine oxidase:
action of enzyme
clinical relevance?
Hypoxanthine –> Xanthine –> Uric acid in purine salvage path
Targeted by allopurinol and febuxostat to treat gout
