Mix3 Flashcards
Why do you use Epi in treating anaphylactic shock?
Stimulation of a1-AR counteracts vasodilation of cutaneous and viscera vasculature thus ^ BP. Epi ^ HR and CO through B1-AR activity to improve BP and peripheral perfusion. Stimulation of B2-AR»_space; bronchodilation, which is beneficial for severe asthmatic reaction.
Site of action of dobutamine:
Primarily B1-AR agonist. Used for HF (inotropic > chronotropic effect)
What blood vessel is responsible for the rapid onset hemarthrosis in ACL injury?
middle geniculate artery (primary blood supply to the ACL)
If a child with flaccid lower extremities, absent ankle reflexes bilaterally, and a poorly developed lumbar spine and sacrum is born to a woman with uncontrolled DM, then what is this condition?
Caudal regression syndrome
- Pt are born with agenesis of the sacrum and occasionally lumbar spine»_space; flaccid paralysis of the legs, dorsiflexed contracture of the feet, and urinary incontinence.
Mutation responsible for Huntington’s Disease:
CAG expansion in HTT gene (Chr 4p)
The L renal vein receives drainage from the L gonadal vein and courses anterior to the aorta, but posterior to the SMA before draining into the ___
IVC
The renal veins join the IVC at level ___
L1/L2
What type of transporter is the glucose transporter (simple diff, primary active, carrier mediated)?
carrier mediated
Why do you need to add primaquine to malaria treatment?
Primaquine is effective against hypnozoites (the latent form of malaria) and is used to prevent relapses of infection.
What is the MOA of the primary drug used to treat malaria?
Chloroquine blocks plasmodium heme polymerase.
What drugs could you use in chloroquine resistant strains of malaria?
mefloquine or atovaquone/proguanil
What’s meant by the “CAMP” test for S agalactiae?
S agalactiae is a type of group B strep. Causes neonatal meningitis and sepsis. Colonies produce a narrow zone of beta-hemolysis that enhances when plated perpendicular to S aureus (indicates pos CAMP test)
Ankylosing spondylitis is assoc with what HLA serotype?
HLA B27
Rheumatoid arthritis is assoc with what HLA serotype?
HLA DR4
What cardiac manifestation is assoc with ankylosing spondylitis?
Ascending aortitis»_space; dilation of aortic ring and aortic insufficiency.
What ophthalmic manifestation is assoc with ankylosing spondylitis?
Anterior Uveitis = blurred vision, photophobia, and conjunctival erythema
___ is the enzyme responsible for loading the appropriate AA to the (3’/5’) terminal hydroxyl group of the CCA tail onto a correct tRNA molecule.
aminoacyl tRNA synthetase, 3’ terminal hydroxyl group is the acceptor stem of the tRNA molecule.
What’s the function of the t-loop in the tRNA molecule?
t loop is needed for binding tRNA molecules to the ribosome. T loop contains pseudouridine, ribothymidine, and cytidine.
Why are methicillin resistant strains of certain bacteria also resistant to cephalosporins?
Because the mechanism of methicillin resistance (mecA chromosomal gene) involves alterations in the penicillin binding protein PBP2a, which is used by both penicillins and cephalosporins.
Selection bias created by selecting hospitalized Pt as the control group is known as ___
Berkson’s bias (study pop from hospital is less healthy than general pop)
What’s the mutation in sickle cell disease?
Nonpolar AA valine replaces charged AA glutamate at position 6 in the Beta globin chain»_space; exposure of hydrophobic portion of Beta globin chain fitting into complementary site on alpha globin chain on another hemoglobin molecule.
What part of the digestive system is the most common site for ulcers caused by H pylori?
The duodenum. H pylori resides in the antrum of the stomach in the prepyloric area where there are few acid secretory cells. Colonization of the gastric antrum»_space; ^ gastric acid secretion, and the duodenum is the first area affected by the increased acid production.
The defects seen in Patau syndrome are the result of a defect in the fusion of the ___ during development.
prechordal mesoderm»_space; catastrophic midline defects (i.e. holoprosencephaly, cleft lip/palate, omphalocele, etc)
What are the cardiovascular manifestations of Pt with William’s syndrome?
supravalvular aortic stenosis
Direct inguinal hernias pass through Hesselbach’s triangle through the superficial inguinal ring due to a weakness of what structure?
weakness of transversalis fascia
** This is why direct hernias tend to happen in older people. Failure of this fascial layer is generally due to acquired connective tissue abnormalities or chronic abdominal wall injury.
Why should you consider co-administering a benzo when starting a patient on an SSRI?
SSRI sometimes take 4 weeks before any noticeable therapeutic effect occurs and their initial activating effects can lead to an increased agitation and anxiety during this period. Temporary course of Benzos is sometimes used during SSRI initiation if there is a significant increase in anxiety related symptoms.
Triazolam, oxazepam, and midazolam would all be considered (short/intermediate/long) acting Benzos:
short (t1/2 < 6 hr)
Diazepam, chlordiazepoxide, and flurazepam would all be considered (short/intermediate/long) acting Benzos:
long (t1/2 > 24 hr)
alprazolam, lorazepam, and temazepam would all be considered (short/intermediate/long) acting Benzos:
intermediate (t1/2 6-24 hr)
Azathioprine is a purine analog used for BM suppression in transplant patients. Co-admin with ___ may allow for lower doses of azathioprine because this drug helps prevent it’s breakdown into inactive metabolites.
Allopurinol. Azathioprine is converted to inactive metabolites with XO and allopurinol inhibits XO.
What’s the MOA of ganciclovir in treating CMV infection?
Ganciclovir = competitive inhibitor of deoxyguanosine triphosphate into viral DNA.
What’s the MOA of trimethoprim as an antibacterial agent?
Inhibits DNA synthesis by acting as a competitive inhibitor for dihydrofolate reductase»_space; decreased availability of thymidine from de novo synth.
What’s the MOA of tacrolimus in causing immunosuppression?
tacrolimus inhibits calcineurin (protein used in activation of transcription factors related to T lymphocyte proliferation).
What’s the MOA of prednisone in causing immunosuppression?
Binds glucocorticoid R and upregulates expression of anti-inflammatory proteins and decreases expression of proinflammatory proteins.
What’s the MOA of isoniazid in treating mycobacterial infections (TB)?
Isoniazid can decrease the synth of mycolic acids. Bacterial catalase peroxidase (encoded by KatG) is needed to convert INH to active metabolite.
Porcelin gallbladder is assoc with increased risk of what type of cancer?
adenocarcinoma of the gallbladder
Porcelin gallbladder = complication of chronic cholecystitis. Due to dystrophic intramural deposition of calcium salts in the setting of chronic inflammation.
