Qbank 3 Flashcards
(86 cards)
1
Q
Which proteins recognize the stop codon in translation?
A
-releasing factors
2
Q
Interferons a and b. Function? What cells produce them?
A
-produced by virus-infected cells (wide variety of eukaryotic cells) and prime neighboring cells that are uninfected (stimulates them to produce anti viral proteins) by helping to degrade viral nucleic acid and protein.
3
Q
Why is pO2 in left atrium and ventricle lower than in pulmonary capillaries?
A
- because oxygenated blood is mixed with deoxygenated blood from bronchial arteries that supply the lungs and thespian veins (from heart) that empties into the pulmonary vein
- pO2 is ~104 in capillaries and drops to 100 by the left atrium
4
Q
Where does methicillin resistant S. aureus commonly colonize in humans asymptomatically?
A
nasopharynx, esp Anterior nares
5
Q
Doses of drugs such as digoxin should be reduced in elderly patients because of age-related reductions in?
A
- renal clearance
- there is no rise in Cr because there is also a reduction in muscle mass with age
6
Q
Pre-eclampsia triad.
A
-hypertension, proteinuria, edema
7
Q
Embryonic layers that pituitary is derived from?
A
- anterior pituitary: surface ectoderm
- posterior pituitary: neural tube/neuroectoderm
8
Q
Which opioids can be used for diarrhea?
A
-loperamide and diphenoxylate
9
Q
Mechanism of N-acetyl cysteine in CF patients?
A
-mucolytic agent, cleaves disulfide bonds in mucus glycoproteins to loosen thick sputum
10
Q
maculopapular rash that starts at face and spreads to trunks and extremities: how to tell between rubella vs rubeola?
A
-finding of post auricular lymphadenopathy indicates rubella
11
Q
Superficial dermal edema and lymphatic channel dilation. What skin condition?
A
-urticaria, aka hives.
form after mast cell degranulation.
12
Q
IgG4 antibodies to Phopholipase A2 receptor causing proteinuria.
A
Idiopathic membranous nephropathy
13
Q
Deficiency in lipoprotein lipase. Disease? Common presentation?
A
- Type I hyper chylomicronemia. High chylomicrons, TG, cholesterol. Creamy supernatant.
- commonly presents with recurring acute pancreatitis
- eruptive/pruritic xanthomas.
14
Q
In a deceleration injury to the aorta, where is the injury commonly located?
A
aortic isthmus, where ligament arteriosum attaches
15
Q
Role of vitamin C in collagen synthesis?
A
-Cofactor of enzyme that carries out post translational hydroxylation of proline and lysine residues. Takes place at RER.
16
Q
Mechanism of niacin for lipid lowering effect?
A
- inhibits lipolysis in adipose tissue
- reduces hepatic VLDL synthesis
17
Q
Strep pneumo and viridians. Which group is bile soluble?
A
Strep pneumo.
18
Q
Eosinophilic apoptotic hepatocytes in acute hepatitis infection. What are the eosinophilic globules called?
A
Councilman bodies
19
Q
What gene mutation commonly seen in melanoma?
A
- BRAF (ser/thr kinase is gene product)
- oncogene that is activated
20
Q
Where do majority of anal fissures occur?
A
posterior midline distal to dentate line
21
Q
How is copper excreted in normal healthy person?
A
- secreted into bile and excreted in bile
- some cleared by kidneys
22
Q
Treatment for enterobiasis (pinworm)?
A
albendazole
-pyrantel palmoate for pregnant patients
23
Q
Which amino acid is an immediate source of nitrogen in the urea cycle?
A
Urea’s nitrogen is derived from NH3 and Aspartate
24
Q
Parasympathetic innervation to parotid gland for secretion by which nerve?
A
CN 9
25
The presence of what factor corresponds to virulence in mycobacterium?
Cord factor (a mycoside). Grow in serpentine cord on media. Inhibits neutrophils, causes mitochondrial destruction, induces release of TNF.
26
Pituitary apoplexy. Describe.
- pituitary hemorrhage most often in preexisting adenoma.
| - cardiovascular collapse can occur due to adrenocortical insufficiency
27
Carcinoid tumors are derived from?
Enterochromaffin cells (endocrine) of intestinal mucosa
28
Celecoxib is a selective _____ inhibitor?
selective COX 2 inhibitor
| -COX 2 expressed on vascular endothelium and smooth muscle cells.
29
myotonia, muscle wasting, cataracts, testicular atrophy, frontal balding, arrhythmia. Difficulty with loosing grip after handshake. Disease? Mechanism of disease?
Myotonic Dystrophy or type 1.
| -CTG trinucleotide repeat. AD.
30
Formation of cold agglutinins seen in?
Mycoplasma pneumonia infection
EBV
CLL
31
schizoaffective disorder vs. bipolar/depression with psychotic features
Schizoaffective
-psychotic symptoms must occur in absence of mood disorder for at least 2 weeks. Mood disorder is present majority of time with psychotic symptoms
BIpolar/depression with psychotic features
-Psychotic features occur exclusively during mood disorder
32
Best drug for lowering triglycerides?
Fibrates: upregulate LPL for increased TG clearance
33
Describe structure of tRNA
- 75-90 nucleotides, cloverleaf form.
- acceptor site is the CCA tail at 3' end
- T arm: thymine, pseudouracil, cytosine for tRNA ribosome binding
- D arm: dihydrouracil residues for tRNA recognition by correct ammoniacal tRNA synthethase
34
Which DNA polymerase has 5' to 3' exonuclease activity to remove RNA primers?
DNA polymerase I
35
Transient vs permanent central DI, where is the damage?
transient: isolate posterior pituitary damage. surviving neurons can undergo axonal regeneration and release ADH into circulation
permanent: hypothalamus damage.
36
Mechanism of infertility of kartegener's syndrome vs CF
- CF: bilateral absence of vas deferens. Azoospermia.
| - Kartegeners: immotile spermatozoa.
37
serious complication of methimazole and propylthiouracil?
agranulocytosis.
| -suspect with onset of fever and sore throat.
38
Serum marker for ovarian epithelial tumor.
CA-125.
39
Migratory thembrophlebitis, jaundice with palpable nontender gallbladder. Suspect what cause? Risk factors?
Pancreatic cancer
- Trousseau syndrome and courvoisier sign
- risks: tobacco use, chronic pancreatitis, diabetes, age greater than 50, genetic predisposition
40
What parts of the brain is atrophy most pronounced in Alzheimer's disease?
- Hippocampus
| - also temporoparietal lobes
41
greatest risk factor predisposing to aortic dissection?
-Hypertension, causing hyaline arteriolosclerosis of vasa vasorum, leads to atrophy of media. Aortic enlargement and increased wall stiffness. exacerbate aortic wall stress and increases risk of intimal wall tear.
42
List the naked viruses
DNA: PAPP- polyomavirus, papillomavirus, adenovirus, parvovirus
RNA: calicivirus, picornavirus, reovirus, hepevirus
43
Cause of narcolepsy.
Decreased hypocretin (orexin) production in lateral hypothalamus
44
Infusion of what substance will make thiamine encephalopathy worse?
- glucose
- thiamine is a cofactor for PDH, a-ketoglutarate dehydrogenase, trnasketolase, and branched chain ketoacid dehydrogenase
- giving glucose without thiamine will make ATP depletion worse
45
Meningococcal meningitis prophalyxis for close contacts of infected patient?
Rifampin. Penetrates well into respiratory tract and will eliminate nasopharyngeal colonization.
46
Which drug is an emergency antihypertensive that activates D1 receptors and also increases renal blood flow and causes natriuresis?
Fenoldopam.
| -increases cAMP resulting in vasodilation
47
HCO3-, PAH, Inulin, creatinine, Na, Cl-, urea, glucose, amino acids. Which sometimes increase/decrease as fluid runs along the PCT?
INCREASE: PAH, inulin, Cr, urea, Cl-
Decrease: glucose, amino acids, HCO3-
48
How does digoxin lower heart rate and decrease AV nodal conduction?
-stimulates vagus nerve to increase parasympathetics to the heart.
49
Recurrent sinopulmonary and GI tract infections. Blood transfusion causes anaphylactic disease. What is the deficiency?
IgA deficiency. They form Ig-G antibodies against IgA when transfused with blood that contain a little IgA.
50
What does Hep D need to infect cells?
-needs to be coated with HbsAg
51
which immunodeficiencies are predisposed to Giardia infections?
- IgA def., Brutons X linked agammaglobinemia, CVID
| - Secretory IgA is a major component of adaptive immunity against Giardia
52
function of organ of Corti?
- transduction of mechanical auditory forces to nerve impulses
- prolonged exposure to loud noises can cause hearing loss due to damage to stereo ciliated hair cells of organ of Corti
53
What anticoagulant drugs affect thrombin time?
Unfractionated heparin and direct thrombin inhibitors
54
Describe 3 phases of acute tubular necrosis and the most significant complication during the last phase?
1. Initiation: ischemic injury to renal tubule precipitate by MI, sepsis, hemorrhage, etc.
2. Maintenance phase: oliguria, volume overload, increasing Cr/BUN. Hyperkalemia
3. Recovery:Gradual increase in output resulting in high volume diuresis. Dehydration and Electrolyte abnormalities can ensue
- Hypokalemia: most serious complication
55
What is the major distinguishing factor between depression and atypical depression? What is good Rx for atypical depression?
- Mood reactivity: improvement in mood in reaction to something positive
- other features of atypical depression: increased appetite and sleep, rejection sensitivity, leaden fatigue
- 1st line: CBT and SSRIs
- 2nd line: Mao Inhibitors are good for atypical depression
56
What features of drugs give preference to hepatic clearance instead of renal clearance?
- lipophilicity and high Vd
- high lipid solubility allows better entry into hepatocytes, and is easily reabsorbed in renal tubules so not cleared by kidneys
57
What is the single most preventable cause of disease and death in the US?
smoking
58
Histology of medullary thyroid cancer
uniform spindle shaped or polygonal cells with extracellular amyloid deposits.
59
Where does neonatal intraventricular hemorrhage usually originate from?
- germinal matrix: highly vascularized and cellular layer of sub ventricular zone where neurons and glial cells migrate from during development.
- intraventricular hemorrhage (bleeding into lateral ventricles, e.g.) is a common complication of prematurity
60
virulence factor that is bound to peptidoglycan cell wall of S. Aureus? what is its function?
Protein A
-it binds to Fc portion of IgG at the complement binding site and prevents complement activation. Impaired opsonization and phagocytosis
61
What is nursemaid's elbow?
- radial head subluxation causing annular ligament to be torn/displaced
- young children less than 5
- arm is extended at elbow and forearm pronated
62
What kind of channel is CFTR?
ATP gated chloride channel
63
What is the length constant of axon? Also called space constant.
How far an electrical impulse can propagate along an axon
| -myelin increases length constant and decreases time constant
64
Characteristic histological findings in GERD?
- inflammatory cells, including eosinophils
- elongated lamina propia papillae
- basal zone hyperplasia
65
Which are the live attenuated vaccines?
-MMR, Sabin polio, nasal influenza, varicella, yellow fever
66
Most common cause of coronary sinus dilation?
-elevated right heart pressure secondary to pulmonary hypertension
67
Histology of intestines in abetalipoproteinemia
- fat accumulation towards tip of villi
- lipids absorbed cannot be transported into the blood
- due to mutation of MTP gene, which functions in folding of ApoB and transfer of lipids to chylomicrons and VLDL for transport of TGs
- absence of ApoB, chylomicrons, VLDL in blood
68
Role of IgE and eosinophils in immune response against parasite
- IgE and IgG coats parasites
- binds Fc receptor on eosinophils, activates eosinophilic degranulation
- antibody mediated cell mediated cytotoxicity.
69
Causes of wound contracture?
- MMP activity encourages myofibroblast proliferation at wound edges and scar tissue remodeling
- pronounced MMP activity causes contractures
70
At FRC, what is the airway pressure and the intrapleural pressure?
- airway pressure is zero and there is no tendency to air to flow one way or the other
- intrapleural pressure is -5
71
The superior thyroid artery courses with what nerve?
Superior laryngeal nerve
72
Mechanism of flutamide
competitive antagonist to the androgen receptor. If used as mono therapy, will cause increase in testosterone level due to negative feedback. Often used with leuprolide.
73
During what lung volume is pulmonary vascular resistance the lowest?
Near FRC
74
What findings using diagnostic imaging are specific to acute cholecystitis?
-Ultrasound: gallbladder wall thickening, pericholecystic fluid
-If ultrasound is not conclusive-->
cholescintigraphy can be used. Radio tracer is injected via IV and images taken. In acute cholecystitis, will show no uptake by gallbladder
75
How does radiation initiate cell death?
- causes double stranded DNA breaks
| - creates ROS
76
What type of vaccine is used for rabies?
- Inactivated vaccine
| - in post exposure prophylaxis: use vaccine and rabies immune globulin
77
What deficiencies can lead to homocystinuria?
1. Cystahionine syntheses deficiency: catalyzes first step of following, requires B6:
- Homocysteine +serine--->cystathionine -->cysteine
2. Decreased affinity of cystathionin synthase for pyridoxal phosphate
3. homocysteine methyltransferase deficiency
- homosysteine-->methionine (requires b12)
78
Warfarin skin necrosis, what deficiency would you suspect in the patient?
Protein C deficiency. Already low protein C, adding warfarin causes quick drop in levels, leading to a procoagulant state since protein C and factor 7 are the first factors to be depleted.
79
What is the prognosis for majority of patients infected with Hep C?
- they progress to chronic stable Hep C
- less than half develop cirrhosis
- only 0-3 % develop HCC
- 15-45% clear the infection
80
Why do patients with nephrotic syndrome have an increased risk for thrombosis?
- loss of ATIII in urine
- creates a hyper coagulable state
- Renal vein thrombosis is a common complication, leading to left sided varicocele in men
81
Mechanism behind biliary colic as a complication of opioid drugs?
-causes contraction of sphincter of oddi, leading to increased pressures in bile duct and gallbladder
82
Signs of irreversible cell injury.
1. nuclear pyknosis, karyorrhexis, karyolysis
2. plasma membrane damage
3. lysosomal rupture
4. mitochondrial permiability/vacuolization
83
Shape of cryptococcus neoformas?
budding yeast or round/oval encapsulated cells.
84
mechanism of influenza vaccine (injected)
- vaccine induces neutralizing antibodies against hemagglutinin
- when exposed to infection, will prevent viral entry into cells
85
Coenzymes required for pyruvate dehydrogenase?
- NAD, FAD, CoA
- Thiamine
- Lipoic acid
86
Describe differentiation of T cells.
- T cell precursor produced in bone marrow
- migrate to Thymus and become CD4+CD8+ cell in cortex
- Positive selection: TCR is able to recognize self MHC via interaction with thymic cortical epithelial cells
- Become single positive CD4 or Cd 8 cells
- Negative selection: via interaction with thyme medullary epithelial cells and dendritic cells. T cells with too strong affinity for self antigen or self MHC are eliminated
