NBME 11 Flashcards
What is inhibin A? What do high or low levels indicate?
Maternal Serum hormone that tests for Down Syndrome.
High levels = Down Syndrome (2nd trimester)
In down free beta-hcg increased in both 1 + 2 trimesters
What would high levels of alpha-fetoprotein in 2nd trimester maternal serum indicate?
Patau Syndrome
Also decreased beta-hCG and PAPP-A in first trimester
What is the role of IL-8?
Major chemotactic factor for PMNs
“Clean up on aisle 8!!” - PMNs come in to clean up
What is granulocyte0macrophage colony stimulating factor (GM-CSF)? when can analogs be useful?
also known as colony stimulating factor 2 (CSF2), is a monomeric glycoprotein secreted by macrophages, T cells, mast cells, NK cells, endothelial cells and fibroblasts that functions as a cytokine. The pharmaceutical analogs of naturally occurring GM-CSF are called sargramostim and molgramostim.
Analogs useful for patients in chemotherapy.
What should be your first step when a patient comes forward about a medical problem that they may feel sad or embarrassed about?
Empathize with patient first, before trying to get to the bottom of the problem.
Which enzyme’s activity does methotrexate inhibit indirectly? What other drug affects this enzyme?
Competitively inhibits dihydrofolate reductase which decreases CH2-THF available for THYMIDYLATE SYNTHASE –> decreased dTMP –> decreased DNA synthesis
5-fluorouracicl (5-FU) has similar MoA
Which chemotherapeutic drug inhibits DNA polymerase?
Cladribine (2-CDA) and Cytarabine (arabinofuranosyl cytidine)
How is HGPRT involved in chemotherapeutic drug MoA?
Activates Azathioprine –> 6-mercaptopurine –> decrease de novo purine synthesis
What pathology would you see in Type 1 Diabetes islet cells?
Autoimmune destruction of beta-cells –> Cell necrosis with lymphocytic infiltrate
What are the effects of thyroxine T4 on bone? What compounds cause a decrease in bone resorption?
T4 has no effect –> converted into T3 which stimulates bone GROWTH
CALCITONIN –> DECREASE in bone RESORPTION
Why do mitochondria encode their own tRNA?
they have a non-standard genetic code
True or False, Mitochondria cannot import proteins or RNA:
FALSE
What drugs decrease urinary calcium concentrations, and what is the MoA?
Thiazide diuretics which inhibit NaCl reabsorption in the early DCT –> decreased Ca excretion
Which antibodies are present in SLE and secondary problems associated with SLE? Which can pose a risk to fetus during pregnancy?
Antinuclear antibodies (ANA)
Anti-dsDNA antibodies
Anti-Smith antibodies
Antihistone antibodies (in Drug-induced lupus)
Lupus anticoagulant, anticardiolipin, anti-beta2 glycoprotein antibodies in ANTIPHOSPHOLIPID SYNDROME (which can occur secondary to SLE) - increase risk of complication during pregnancy
Which disease(s) present with Auer rods?
Acute myelogenous leukemia (AML)
1 year old with microcytic anemia, normal WBC and platelet counts and low reticulocytes?
Iron deficiency anemia
What carcinogen can lead to a renal cell carcinoma?
Cigarette smoking
What cells function as the stem cells of the respiratory system?
Type II pneumocytes
What are the causes of transudative effusion? Exudative?
Transudate (thin, hypocellular, protein poor) - from increased hydrostatic pressure, decreased oncotic pressure, or Na+ retention
Exudate (thick, cellular, protein rich,) - From lympatic obstruction, inflammation/infection, malignancy
A deficiency of which enzyme will lead to GM2 ganglioside build up? Sphingomyelin? Ceramide trihexoside? Cerebroside sulfate?
Tay-Sachs disease –> Hexosaminidase A
Niemann-Pick disease –> Sphingomyelinase
Fabry disease –> alpha-galactosidase A
Metachromatic leukodystrophy –> Arylsulfatase A
What are patients exposed to vinyl chloride at risk for? 2-naphthylamine/benzidine?
Liver - angiosarcoma
Bladder - transitional cell carcinoma
What carcinogens can cause transitional cell carcinoma?
Pee SAC
Phenacetin, smoking, aniline dyes, cyclophosphamide
What does the carotid massage action lead to?
increased stretch –> increased afferent baroreceptor firing –> increased AV node refractory period –> increased HR
Which cells are responsible for re-epithelialization of wounds?
Macrophages stimulate cells to re-epithelialize wound and form granulation tissue.
What is immune senescence?
the normal process in which the immune system ages and degenerates
senescence literally means deterioration of age
Adipocytes maintain blood glucose level at 3 days of starvation by what means?
Glucagon activating hormone sensitive lipase to increase release of free fatty acids.
A new drug is made that decreases length of time that reactivated HSV rash is present. What effect would this have on incidence and prevalence?
Incidence doesn’t change
Prevalence would decrease
What is Dronabinol used for?
Derivative of THC - Relieves nausea and vomiting caused by chemotherapy.
What is metoclopramide used for?
D2 receptor antagonist, increases resting tone, contractility, LES tone, and motility. For diabetic and postsurgery gastroparesis. Antiemetic
SE- increased parkinsonian effects. interacts with digoxin and diabetic agents. Do not use in parkinson or small bowel obstruction
What is misoprostol used for?
induces labor, treat stomach ulcer, treat post partum bleeding. synthetic prostoglandin E1
What drug would you use pre-operatively to reduce risk of regurgitation and pulmonary aspiration of gastric contents during the operation?
Scopolamine
A 6 month old boy develops fever and a paroxysmal severe barking cough. Which enzyme’s increased activity would be responsible for defective chemotaxis and oxidative metabolism?
Bordatella Pertussis - Adenylyl Cyclase toxin activity
Where is the germinal matrix?
The germinal matrix is the site of proliferating neuronal and glial precursors in the developing brain, which is located above the caudate nucleus, in the floor of the lateral ventricle, and caudothalamic groove.
What are ferruginous bodies?
Asbestos bodies (golden-brown fusiform rods resembling dumbbells) - from asbestosis e.g. instulation worker
What are birbeck granules?
tennis-racket shaped granules in Langerhans cell histiocytosis
What is condyloma acuminata?
Genital wart associated with HPV infection
Which drugs function as dopamine agonists? And what are they used for?
Ropinirole and Pramipexole (non-ergots) - Parkinson and restless leg syndrome
Bromocriptine (ergot) - treatment of pituitary tumors, Parkinson’s disease (PD), hyperprolactinaemia, neuroleptic malignant syndrome, and type 2 diabetes.
What is the mechanism of osteomalacia as a result of glucocorticoids?
Glucocorticoids increase bone resorption by stimulating osteoclastogenesis by increasing the expression of RANK ligand and decreasing the expression of its decoy receptor, osteoprotegerin.
A patient has a gunshot wound in the mid-left region of the abdomen and the abdominal cavity is filled with blood, what organ is most likely injured?
Spleen
What is pleiotropy? Example of this?
one gene contributing to multiple phenotypes
Phenylketonuria (PKU) manifests with light skin, intellectual disability and musty body odor
Different phenotypes dependent on parental origin is which type of genetic mechanism?
Imprinting
What is bacillary angiomatosis?
Benign capillary skin papules found in AIDS patients
Caused by Bartonella henselae infections (neutrophilic infiltrate differentiates from Kaposi sarcoma)
What is leptospirosis?
Leptospira interrogans infection (SPIROCHETE) - Flu-like symptoms, myalgias, jaundice, photophobia with conjunctival suffusion
Hawaii Surfers
What is lymphogranuloma venereum?
Small painless ulcers on genitals which can become swollen painful inguinal lymph nodes that ulcerate (buboes)
Caused by Chlamydia trachomatis serotypes L1, L2, L3
What causes Q fever?
Coxiella burnetti (inhaled spores from cattle/sheep amniotic fluid)
Culture negative endocarditis
A patient presents with a painless chancre and VDRL is positive. Another patient presents with bulls eye rash after a hiking trip in upstate New York. What is a similarity between these two presentations?
Chancroid = Syphilis from Treponema pallidum
Bulls eye rash = Lyme disease from Borrelia burgdorferi
Both are SPIROCHETES
A left posterior communicating artery aneurysm would impinge on which nerve?
CN III - Oculomotor nerve
A cleft lip develops in failure of fusion of which structures? Cleft palate?
Failure of fusion of the maxillary and medial nasal processes (formation of primary palate)
Failure of fusion of two lateral palantine processes or lateral palantine processes with the nasal septum and/or median palatine process
What is the mechanism of action of Bosentan? What is it used for?
a competitive antagonist of endothelin-1 at the endothelin-A (ET-A) and endothelin-B (ET-B) receptors
Tx of pulmonary hypertension
What suffix applies to drugs that block AT II receptors?
-SARTAN
What can be found on pathological gross specimen of the Pancreas in Type II Diabetes?
Amyloid buildup in islets
What is renal osteodystrophy and what key serum ion/hormone changes would you see in this condition?
Type II diabetes mellitus leading to secondary hyperparathyroid, which can cause bone resorption.
Decreased Calcium
Increased phosphate and PTH
Which enzyme is rate-limiting in glycogenolysis and initially activated in hepatocytes by exercise? Which is responsible for releasing monomers of glucose from glycogen?
Phosphorylase Kinase
Debranching enzyme
What is Weber’s syndrome? (hint; lower midbrain infarct)
(superior alternating hemiplegia) is a form of stroke characterized by the presence of an ipsilateral oculomotor nerve palsy and contralateral hemiparesis or hemiplegia.
What is Gerstmann syndrome? (hint: angular gyurs - inferior parietal lobule - infarct)
Dysgraphia/agraphia
Dyscalculia/acalculia: difficulty in learning or comprehending mathematics
Finger agnosia: inability to distinguish the fingers on the hand
Left-right disorientation
What effects does secretin have on digestive secretions?
increase pancreatic bicarbonate secretion
increase bile secretion
decrease gastric acid secretion
What effects does ghrelin have on GI secretions?
Ghrelin stimulates hunger and increases Growth Hormone secretion
What drug can be used to treat both hypertension and Raynaud’s phenomenon?
Nifedipine