Deck 2 Flashcards
What are the different stop codons? Start codon?
UAG, UAA, UGA; AUG
What serum marker is produced by epithelial ovarian cancers?
CA-125 (protein expressed epithelial cells lining mullerian structures
What causes reperfusion injury?
Oxygen radical generation, mitochondrial damage, and inflammation
What form of glucose is selected by transmembrane transporters? Difference - GLUT 4 & GLUT 2?
D-glucose (not L glucose). GLUT4 = insulin dependent in muscle/ adipose cells. GLUT2 = exports glucose into circulation in liver, small intestine, kidney
Why is cilostazol used in peripheral arterial dz (what does it do)?
Is a PDE inhibitor (increases cAMP) which inhibits platelet aggregation + direct arterial vasodilator
What allows a bacteria to survive boiling? Examples?
Spore-forming. Ie: Bacillus anthracis, Clostridium
In what time is a patient more susceptible to left ventricular wall rupture?
5-14 days after MI due to weakening of inflammation and necrosis
What results from orbital floor fracture?
Damage to infraorbital nerve = numbness and paresthesias of upper lip, cheek, gingiva
What results from aldolase B deficiency? What does this enzyme do?
Hereditary fructose intolerance; It metabolizes fructose-1-phosphate (a toxic product of fructose metabolism)
What drugs have antimuscarinic effects?
atropine, TCADs, H1 antagonists (diphenhydramine), neuroleptics, antiparkinson drugs
What drugs are metabolized by acetylation (in liver)?
Isoniazid, dapsone, hydralazine, procainamide
3 mitochondrial inherited diseases?
Leber hereditary optic neuropathy (bilateral vision loss), myoclonic epilepsy with red ragged fibers (myoclonic seizures and myopathy associated w exercise), Mitochondrial encephalomyopathy with lactic acidosis and stroke like episodes (MELAS)
What are the two main cytokines that stimulate B cells after exposure to antigen? Difference?
IL-4 & IL-5: 4 is responsible for B cells growth and isotope switching, stimulates secretion of IgE (type 1 rxns), and Th0 -> Th2; 5 is responsible for B cell differentiation, stimulates IgA production and eosinophil activity (parasitic)
What does the Fas receptor do? What problems with defect?
Initiates extrinsic pathway of apoptosis (through FADD aka death domain in cytoplasm). Defect = prevents apoptosis and autoreactive lymphocytes
What 2 things are needed for osteoclast differentiation?
M-CSF and NF-kB (RANK-ligand)
What would suggest Gilbert syndrome?
No apparent liver dz but mildly elevated unconjugated bilirubin provoked by stressor, exercise, etc; From reduced production of UDP glucuronyl transferase
How is Dubin Johnson different from Gilbert?
Elevated conjugated bilirubin
What nerve passes through posterior triangle of neck? What muscles? What happens if injured?
Spinal accessory; Trapezius & sternocleidomastoid- causes impaired abduction, shoulder droop, winging of scapula
What forms the fibrous cap in atherosclerotic plaques?
Vascular smooth muscles cells
What is a complication of long lasting meds for asthma
Oral candidiasis (low dose inhaled corticosteroids); So patients should prophylactically rinse mouth
What are the main adverse effects of nitrates?
headaches, cutaneous flushing, lightheadedness, hypotension, reflex tachycardia
In what ways does propanalol help with thyroid storm (thyrotoxicosis)?
Reduce sympathetic (HR, anxiety, etc) and peripheral conversion of T4 - T3 by inhibiting iodothyronine deiodinase
What meds alter thyroid hormone synthesis?
PTU (inhibits thyroid peroxidase + 5’-deiodinase) & Methimazole (only thyroid peroxidase)
Difference between dynein and kinesin?
Dynein causes retrograde, kinesin causes anterograde
Mechanism of action of metformin? SE? Contraindications?
Decreases hepatic gluconeogenesis (inhibits 1st enzyme in ECT) and increases peripheral glucose use; SE= lactic acidosis- increased in renal problems, hepatic problems, avoid in CHF & alcoholism (increased lactic acidosis)
Proximal muscle weakness in legs and arms- difficulty lifting things, etc? Describe findings
Polymyositis- biopsy shows endomysial mononuclear inflammatory infiltrate and patchy muscle fiber necrosis. ANA and Anti-Jo-1 antibodies (anti-histidyl-trna-synthetase; May be paraneoplastic for Adenocarcinoma
Antimitochondrial Abs? Anti-smooth muscle Abs?
- PBS 2. Autoimmune hepatitis (middle aged women)
What is finasteride used for? Mechanism of action?
BPH and androgenic alopecia. Inhibits 5-alpha-reductase- decreases peripheral conversion of testosterone to DHT
What is the order of conduction velocity of cardiac tissues?
Fast to slow = Park AT Venture Avenue: purkinje, Atrial muscle, ventricular muscle, AV node
Describe cardiac and renal complications of SLE?
Cardiac = accelerated atherosclerosis, small vessel necrotizing vasculitis, pericarditis, Libman-sacs endocarditis (small, sterile vegetations); Renal = diffuse proliferative glomerulonephritis with “wire-loop” structures due to subendothelial immune complex deposits
What characterizes myotonic dystrophy? Inheritence?
Abnormally slow muscle relaxation: inability to let go of door handle/ loosen grip. Cataracts, frontal baldness, gonad atrophy. Type 1 muscle fibers. AUTO DOMINANT- CTG repeats
What do anti-Smith abs in SLE target?
Smith proteins- combine with snRNA to form snRNP (splice RNA)
What lab test is specific for drug-induced lupus?
Anti-histone Abs
What effect does hepatic encephalopathy have on neurotransmitters? What is Tx?
Increase inhibitory (GABA) and decrease excitatory; Tx = Lactulose: Bacterial action on lactulose acidifies colon -> traps ammonia in non-absorbable ammonium ions and is excreted in stool
MOA of ethosuximide? Phenytoin?
Ethosuximide: Blocks T-type Ca channels in thalamic neurons; Phenytoin blocks Na channels in cortical neurons
Where does most water absorption occur in kidney?
Proximal tubule
What 2 conditions cause congenital QT prolongation?
Romano Ward (autosomal dom) & Jervell and Lange Nielsen syndrome (autosomal recessive w neurosensory deafness)
What does cholesterol 7-a hydroxylase do? What blocks it?
Catalyzes rate limiting step in bile acid formation. Inhibited by fibrates -> less cholesterol solubility = more cholesterol stones
What is rate limiting step in cholesterol formation?
HMG-CoA -> mevalonate (HMG-CoA reductase)
What receptor do antipsychotics block?
D2 receptor- disinhibit prolactin
