Becker's vs. Duchenne's in terms of gene alterations
- Becker's: in-frame deletions/insertions (altered protein made)
- Duchenne's: frameshift deletions/insertions (truncated protein as a stop codon is found)
Abetaliproteinemia - mutation in what gene?
- Microsomal TG transfer protein (MTP)
- Low cholestrol and vitamin E levels
How is paternity test confirmed?
Using PCR probes that amplify microsatellite repeats
Pap smear of Chlamydia trachomatis
Large cytoplasmic vacuole with reticulate bodies in epithelial cells
- NK-1 antagonist
- Treats nausea post-leukemia conditions
Patient has abdominal pain and diarrhea, but presents with dark urine and gram (-) rods as well as mixed flora in the urine sample. Abdominal dz?
- Enteric fistula into the bladder causes mixed flora presence.
Where does PTH act on the kidney?
- PCT: inhibits Na+/PO4 cotransport causing PO4 excretion
- DCT: increases Na+/Ca++ exchange - increases Ca+2 absorption
Heart defect found in Cri-du-chat syndrome
Why can tricyclic antidepressants be used to treat Parkinson's?
- Anti-cholinergic side effects of TCA
- (Parkinsons have decreased dopamine and increased Ach)
Dx test for primary syphilis
Dx test for secondary syphilis
Dx test for tertiary syphilis
- Darkfield microscopy
- VDRL which can be followed with an FTA-ABS (both will be positive)
- FTA-ABS (VDRL may be negative)
Schwann cell (myelinates a single axon)
Oligodendrocyte (myelinates multiple axons)
Neurotransmitter released by methamphetamines which gives you a "high"
Inducing dopamine release (central affect)
Therapy for Wilson's disease
- Trientine (better tolerated, less AE
Initial event in the pathogenesis of pre-eclampsia
- Placental ischemia
- 1)HELLP syndrome
- (hemolysis, elevated liver enzymes, low platelets)
- 2) DIC-mediated ischemic damage to the brain
Action of cyclophosphamide
- Covalently crosslinks DNA at the guanine site
- (bioactivation by the liver)
Urine metabolites of carcinoid syndrome vs. pheochromocytoma
- 5-hydroxy-indoleacetic acid
How does brown adipose tissue produce heat in a newborn?
Uncouples oxidative phosphorylation with thermogenin
Undescended testes, what peptide hormones are decreased and elevated
- Testes are not in the scrotal sac, hence, seminiferous tubules become atrophied.
- Inhibin levels decrease (Sertoli cells secrete inhibin) and FSH levels increase
n.b. 2nd sexual characteristics and sexual drive are not affected, as Leydig cells are not damaged.
What recognizes stop codons in mRNA (UAA, UGA, UAG)
- Releasing factors
- release the polypeptide chain from the ribosome and disassemble the unit
How can plaque stability be reduced to cause a MI?
- Inflammatory macrophages secrete metalloproteinases, which degrade collagen
- Plaque stability: collagen synthesis that strengthens the fibrous cap
Superior thyroid artery injury can damage what nerve, and will cause what affects?
- Superior laryngeal nerve (branch of vagus)
- Affects cricothyroid and sensory innervation ABOVE the vocal cords
Which kidney stones are not seen on an x-ray?
Uric acid (radioluscent)
Positive VDRL and pleocytosis are diagnostic of what stage of syphilis
- Tertiary (neurosyphilis)
What has happened to a patient who has renal disease after a coronary angioplasty?
- Cholestrol gets pushed from the larger arteries and enters the smaller vessels causing ischemia of other tissues
- Also: livedo reticularis (skin colour changes in lower extremities), cholestrol deposits in the retina
Most common cause of fetal hydronephrosis
- Inadequate recanalization of the uteropelvic junction
- (ureters should be fully canalized (lumenized)before metanephros works
n.b. inadequate development of vesiculouteral junction can cause hydronephrosis in a BABY
Folate deficiency inhibits the formation of what molecule?
- Inhibits DNA synthesis, promotes megaloblastosis and erythroid precursor cell apoptosis
Characteristics of a drug whose bioavailability = 4L (i.e. remains in the plasma)
- Large molecular weight
- Highly bound to protein
- Highly charged (hydrophilic)
these prevent it from diffusing across the interstitial membrane or cell membranes and having a higher Vd of the interstitial volume
n.b. Vd is not related to the distribution of the drug
What factor mediates the following sx: fatigue, anemia, anorexia, presence of a cancer
What drug is superior to ASA in vasodilating and inhibiting platelet aggregation
Which kidney stone can be detected by the cyanide-nitroprusside test?
- Cyanide converts cystine to cysteine and then nitroprusside binds to cysteine, causing a red-purple urine
Decreased LPL (lipoprotein lipase) activity will increase what lipid? Presentation
- Most common presentation = acute pancreatitis
What process is altered by DNA methylation (alters gene expression but not the genetic sequence?
Process when one gene influence has multiple phenotypic affects
chromosomal non-disjunction during meiosis or mitosis
aneuploidy (e.g. down syndrome)
A test has a 95% specificity (test is negative for patients who don't have prostate cancer). What is the probability of getting at least 1 positive test result if you run 8 tests?
- (0.95^8 = being TN all 8 times)
- (0.05^8 = being TP all 8 times)
How does radiation initiate cell death to treat cancer?
- 1. DNA ds breaks
- 2. formation of free radicals
- Affects rapidly dividing cells (cancer cells) + rapidly dividing ones (bowel and skin)
Thrombus extraction followed by a rapid surge of CK. Dx?
- Reperfusion injury
- Occurs secondary to oxygen free radical perfusion, inflammation, mitochondrial damage
- CK levels increase due to cell membrane damage
Penicillins inhibit transpeptidase. What is the enzyme's normal function?
Transpeptidase will catalyse final cross-linking step in the PG cell wall formation = joins AA to the terminal D-ala-D-ala end of another PG
Penicillins are analogs of D-ala-D-ala, which inhibit TP by binding covalently to its active site
Abdominal aortic aneurysm starts off as what process?
- Intimal fatty streak (lipid-filled foam cells derived from macrophages and smooth muscle, which have engulfed lipoproteins esp LDL)
Vancomycin's red man syndrome is mediated by what factor
Niacin's flushing and warmth is mediated by what factor
- (side tx = aspirin)
T cells (IL-2) and macrophages (IL-1 and TNF)
Renal veins and common iliac veins join the IVC at what level?
- Renal veins: L1/L2
- Common iliac veins: L4
Syphilis can produce thoracic aortic aneurysms. What is the first step in manifestation?
Vaso vasorum obliteration
Development of a vaccine to target gonocccal pili, but cannot induce long-lasting immunity. Why?
Antigenic variation (pili genes undergo recombination)
High frequency sounds are located at what part of the ear
Oval window, round window, stapes, basilar membrane
Low frequency sounds are heard at what part of the ear
scala vestibuli, scala tympani, helicotrema
Common adverse effect of streptokinase
when given for a MI and patient later has asymmetric pupils, and irregular bleeding
- converts plasminogen to plasmin, which degrades fibrin.
- can cause hemmorhage
Location of unilateral hearing loss
Location of bilateral hearing loss
- U/L = cochlear nerve
- B/L = damage of stereociliated cells at the organ of Corti
What enzyme converts pro-carcinogens to carcinogens?
- cytochrome P450 monooxygenase
- (also metabolizes steroids, alcohol, toxins making it more soluble and easier to excrete)
Li-fraumeni syndrome associated with what cancers?
- adrenal cortex
Rb gene associated with what cancers
Hyper-TG most efficient tx
Niacin and gemfibrozil
Progesterone has what affect on the endometrial cells, and withdrawal causes what
- Maintenance during the luteal phase, growth of endometrial stromal cells into decidual cells
complications of varicose veins
- venous stasis/congestion
- superficial venous thrombosis
- skin ulcerations (most common on the medial malleolus)
mechanism of Candida overgrowth in the vagina
- use of broad-spectrum Abx suppresses the gram (+) bacterial overgrowth
- others: OCs, corticosteroids, uncontrolled DM
what CMV disease is seen in immuno-competent patients and in HIV patients
- Mononucleosis: atypical lymphocytes, elevated liver transaminases, heterophile Ab (-)
Hemangiomas that appear in newborns and regress spontaneously by 5-8 years of life.
Dilation of central arterole and capillary network
- Spider angioma
Proliferation of capillaries and postcapillary venules in the dermis
- Cherry hemangiomas
- do not regress spontaneously; increases with age
1st adverse effect of ACE inhibitors
- 1st dose hypotension
- n.b. be careful with diuretics (as hypovolemic, hyponatremic)
Riboflavin (B2) works in what step of the TCA cycle?
- with succinate DH
- conversion of succinate to fumarate
Adult-type coarctation of the aorta patients commonly die of what conditions
- Increased BP proximal to the coarct
- Ruptured aortic aneurysm and intracranial hemorrhage and LVF
Sensation of a full bladder, no voiding, blood at the urethral meatus, high riding boggy prostate is associated with what urethral injury?
- Posterior urethra associated with a pelvic fracture
- (anterior urethral injuries occur in straddle injuries)
Protein that binds to integrin, collagen, and GAG
- Fibronectin (glycoprotein) made by fibroblasts
- fx: cell adhesion and migration