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
HGPRT
action of enzyme
clinical relevance
converts hypoxanthine back to IMP and guanine back to GMP in the purine salvage pathway
lack of enzyme = Lesch Nyhan, X linked disease
-self mutilation
-gout
-movement disorder
ANGRY LITTLE FAT BOY ANGER PROBLEMS!!!
Adenosine deaminase:
action of enzyme
clinical relevance?
adenosine –> inosine in purine salvage path
lack of this enzyme= major cause of SCID!
lack both B & T cells!
