More stuff I wish I'd known Flashcards
(331 cards)
1
Q
Patient presents with evidence of right ventricular hypertrophy (ECG, heaves) and bilateral pitting edema with no other signs of pulmonary dysfunction?
A
This means the right ventricle is working hard, suggesting pulmonary hypertension. Without evidence of left heart failure (which eventually causes right heart failure), most common cause is Pulmonary Endothelial Dysfunction leading to hypertension (IPAH).
2
Q
Cause of pulmonary hypertension in an older adult, maybe a smoker?
A
COPD causes pulmonary hypertension
3
Q
Most common symptom of uterine fibroid? Why? Also called?
A
Heavy menstrual bleeding due to impaired contractility and increased surface area. This is a leiomyoma, tumor of smooth muscle.
4
Q
mucosal hemorrhage and patchy areas of necrosis on colonoscopy? Two mechanisms?
A
Ischemic colitis; Can be caused by:
1) occlusion of bowel vascular supply or
2) hypoperfusion due to decreased cardiac output
5
Q
low bone mineral density, thin sclera?
A
Think osteogenesis imperfecta - affects bones, tendons, ligaments, skin, sclera. Due to mutation in COL1A1 or COL1A2 –> defect in Type 1 collagen production
6
Q
“thin sclera” is code for?
A
blue sclera –> osteogenesis imperfecta
7
Q
Lack enzyme Acyl-CoA dehydrogenase?
A
No access to Acetyl-CoA from triglycerides –> no ketone production during starvation
8
Q
What is the enzyme deficiency if someone undergoing starvation has no ketone bodies in their blood?
A
Acyl-CoA dehydrogenase
9
Q
Lineweaver-Burke plot components?
A
1/S on X-axis (s is [substrate])
1/V on Y-axis (V is rxn velocity)
slope = Km/Vmax
10
Q
progressive erosion of articular cartilage, particularly within large, weight-bearing joints? Primary cause and risk factors?
A
Osteoarthiritis –> chiefly caused by excessive biomechanical stress and metalloprotease activity; Chief risk factor is advanced age, female, family history, and trauma/obesity/deformity
11
Q
pellagra-carcinoid connection?
A
carcinoid tumor constitutively produces serotonin, depleting niacin in the process –> pellagra
12
Q
penicillin effect on Candida albicans?
A
None - chitinous cell wall is impervious
13
Q
Describe prokaryotic genome
A
haploid, single chromosome or DNA strand (no nucleus)
14
Q
genetic sequence that facilitates initiation of translation in prokaryotes?
A
Shine-Delgarno sequence
15
Q
Patient may have Chron’s disease. Where should you biopsy?
A
Terminal ileum is the most frequent site of involvement. Colon is the second most common site of involvement
16
Q
New drug in the mix mucks with CYP450. What happens to PT of someone on coumadin?
A
If CYP450 is inhibited, see gradual increase in PT to a new steady state
If CYP450 is enhanced, see gradual decrease in PT to new steady state
17
Q
Patient presents with confusion, involuntary movements, labs show hepatitis A, B, C, etc.? Treatment?
A
Hepatic encephalopathy. Start lactulose to acidify gut and convert NH3 to NH4+, stopping absorption
18
Q
Macrolide effect on CYP450? Mechanism? Exception? Warfarin example?
A
Macrolides inhibit CYP450 activity. Erythromycin, for instance, is a competitive inhibitor. Azythromycin is an exception, does not inhibit CYP450. Pt on Warfarin must reduce dose while taking macrolide, then restore after discontinuing.
19
Q
cardiac glycoside MoA?
A
Inhibit sodium-potassium-ATPase pump, leading to increase in intracellular Na+. Sodium reroutes, leaves cell via sodium-calcium exchange, leading to increased intracellular calcium. Increased intracellular calcium causes increased contractility of cardiac myocytes.
20
Q
treatment for chronic systolic heart failure?
A
digoxin, though treatment does not reduce mortality, only symptoms
- narrow therapeutic index
- produces a central vagal stimulating effect, which slows AV and SA node conduction
- gives increased oomph to left ventricle
21
Q
Treatment for atrial defibrillation?
A
Try digoxin
22
Q
Side effects of digoxin?
A
Increased serum potassium (Na+K+-ATPase is inhibited)
Premature ventricular contractions
23
Q
Contraindication for digoxin? Scenario?
A
hypokalemia; watch loop diuretic interaction, kidney failure affects serum digoxin levels (decreased perfusion, etc)
24
Q
how to reverse digoxin toxicity?
A
Use digoxin specific antibody fragments, which bind digoxin. Fragments come from sheep-derived immunoglobulin after sheep exposure to digoxin
25
milrinone?
Phosphodiesterase inhibitor --> leads to decreased breakdown of cAMP
- - mimic Beta1 agonist in heart (stimulatory)
- - positive inotropic effect
- - basically Viagra for your heart (TM), though PDE-5 inhibitor increases cGMP for vascular dilation
26
nesiritide?
Synthetic form of brain natriuretic peptide (BNP)
- -> increase cGMP in smooth muscle cells --> venous/arteriolar dilation
- -> sodium loss through diuresis
27
patient with CHF has yellow-tinged visual disturbances?
Using digoxin, known side effect, maybe the patient now has decreased renal function
28
Describe renin release?
Controlled in large part by Beta1 receptors on juxtaglomerular cells of nephron - site of synthesis, storage, and release is the juxtaglomerular apparatus
29
hormone that increases GFR? How?
angiotensis II (efferent arteriole constriction)
30
angiotensis II direct effects?
- act on proximal convoluted tubule to increase sodium bicarb reabsorption
- increase aldosterone release from the adrenal cortex
- efferent arteriole constriction
31
aldosterone site of action? Does what?
acts on collecting ducts to increase sodium and fluid retention at the expense of potassium (potassium wasting)
32
"-pril" suffix?
ACE inhibitors - enalipril, captopril, lisinopril, ramipril
33
someone faints when given ACE inhibitor? How to proceed?
really high renin levels suddenly repressed, as in someone with heart failure. Sudden hypotension/syncope. Start with low dose, then slowly increase.
34
electrolyte effect of ACE inhibitor? Also see?
hyperkalemia, hyponatremia
| See higher levels of renin/angiotensis I as an accumulation of pre-enzyme intermediates
35
treatment for patient with albuminuria and BP > 130/80?
start ACE inhibitor
36
Diabetic patient with albuminuria? How detected?
Start ACE inhibitor to halt progression of renal disease. Will not fine protein on urine dipstick, need to do urinalysis to see 30-300 mg/day loss rate
37
non-specificity of ACE?
also converts or breaks down bradykinin and substance P
38
contraindication for ACE inhibitor?
hereditary angioedema, C1 esterase deficiency, patient with bilateral renal artery stenosis or other renal vascular disease, pregnancy
39
Why are ACE inhibitors contraindicated during pregnancy? Alternative
fetal hypotension, inuria, renal failure. Use labetalol instead to control BP.
40
ACE interaction to monitor?
Watch coadministration with NSAIDS --> precipitate acute renal injury when combined with decreased prostaglandins keeping the afferent arteriole open
41
"-sartan" suffix? MoA difference from ACE inhibitor?
Angiotensin Receptor Blocker (ARB - losartan, valsartan, candasartan)
Does not inhibit ACE, so no ACE inhibitor side effects like cough, other bradykinin/substance P effects
You will still see hyperkalemia
42
earlier blocker in RAAS? MoA?
aliskiren - blocks angiotensinogen to angiotensin I
43
PDE MoA? Specifics? Common stimulant?
prevents degradation of and inactivation of intracellular second messengers cAMP/cGMP. Many different forms, PDE1-5,7,10
Caffeine is a nonspecific PDE inhibitor
44
surgical landmark for locating appendix?
Teniae coli
45
Function of the teniae coli?
3 longitudinal bands of smooth muscle that run the length of the colon --> contract to form haustra
46
common transcription error in prescribing?
| what about "2.5" versus "25"
Watch trailing zeros, don't do it! Write "2" not "2.0"
| Shut up, smart alec.
47
Structures passing through greater sciatic foramen (4 groups)?
1) Sciatic nerve and piriformis muscle
2) Superior gluteal vessels and nerve
3) Inferior gluteal vessels
4) internal pudendal vessels
48
Piriformis syndrome?
compression of sciatic nerve by enflamed piriformis muscle
49
fixed, dilated pupil in someone who suffered a stroke?
temporal lobe --> expanding, space-occupying lesion (blood) causes increased icp leading to uncal herniation --> compress oculomotor nerve --> damage preganglionic parasympathetic fibers --> dilation
50
pathogen susceptibilities in X-linked agammaglobulinemia? Deficient cell type?
low/absent circulating CD19+/CD20+ B cells --> pyogenic bacteria, enterovirus, Giardia lamblia
51
what are pyogenic bacteria?
Those that cause pus
52
PGI-2 precursor?
made from PGH-2 by prostacyclin synthase
53
SSRI overdose remedy? MoA?
Cyproheptadine --> nonspecific 5-HT receptor antagonist
54
who makes the fibrous cap on an atherosclerotic plaque?
vascular smooth muscle cells
55
thiazide diuretic activity is where?
Distal convoluted tubule
56
thiazide effect on Ca++?
promotes hypercalcemia
57
bisphosphonate MoA?
inhibit mature osteoclast-mediated bone resorption
58
Ethanol/isopropranol antiseptic MoA? Limitation?
Disruption of cell membranes and denaturation of proteins. Best at 60-90% concentration
Does not destroy bacterial spores, but pretty much everything else.
59
Chlorhexidine antiseptic MoA? Limitation?
Disruption of cell membranes and coagulation of cytoplasm. Not sporicidal.
60
sporicidal antiseptics?
hydrogen peroxide and iodine
61
Histones and DNA?
Nucleosome core comprised of 2 each of H2A, H2B, H3, and H4. H1 lies outside the core, binds linker segments of DNA beteen nucleosomes.
62
variability of clinical manifestations of suspected mitochondrial inherited disease?
Heteroplasmy - due to presence of different mitochondrial genomes within a single cell
63
Dysphagia in a patient with iron deficiency?
Due to formation of esophagial webs (Plummer-Vinson or Patterson-Kelly Syndrome)
64
Woman with "tender bulge" below the inguinal ligament, lateral to pubic tubercle?
Femoral hernia -- content protrudes through femoral ring, inferior to inguinal ligament. High risk of strangulation.
65
Describe steps of Gq signalling system (3 major steps)
1) Ligand binding causes exchange of GDP for GTP on alpha subunit. The alpha subunit undergoes conformational change to expose phospholipace C (PLC) activating site
2) Active PLC hydrolyzes PIP2 to DAG (Diacylglycerol) and IP3
3) DAG directly stimulates protein kinase C (PKC), but major activator of PKC is increased Ca++ due to IP3-mediated release from ER. PKC is major effector molecule
66
IP3 role in Gq signalling?
Release Ca++ from endoplasmic reticulum, increasing intracellular level activates Protein Kinase C
67
competitive inhibitor effect on Km and Vmax? Why?
Km will get larger, but Vmax will be unaffected. Km increases because in order to get 50% active sites occupied, you need more substrate in order to overcome the competitive inhibitor. Vmax doesn't change because you can always saturate with substrate to defeat the competitive inhibitor, though the enzyme still works at the same speed.
68
Eukaryotic RNA Polymerase I?
synthesizes a pre-rRNA 45S (35S in yeast), which matures into 28S, 18S and 5.8S rRNAs which will form the major RNA sections of the ribosome.
69
Eukaryotic RNA Polymerase II?
synthesizes precursors of mRNAs and most snRNA and microRNAs.[9] This is the most studied type, and, due to the high level of control required over transcription, a range of transcription factors are required for its binding to promoters.
70
Eukaryotic RNA Polymerase III?
synthesizes tRNAs, rRNA 5S and other small RNAs found in the nucleus and cytosol.
71
Where do you find 1/Vmax on Lineweaver Burke plot?
It's the y-intercept
72
Where do you find -1/Km on Lineweaver Burke plot?
It's the x-intercept
73
Site of aldosterone action in the kidney? What is the effect?
Principals cells in the collecting duct, activates basolateral pump pulling 3 Na+ out of the cell and pumping 2 K+ into the cell. The resulting gradient then pulls sodium into the cell from the collecting tubule (and dumps potassium out), with a net result that water is also pulled into the cells from the collecting duct.
74
Most potent activator of aldosterone release?
Serum potassium levels
75
Describe decidualization (4)?
Changes in the uterus due to progesterone in preparation for receiving an embryo:
- eosinophilic proliferation around arterioles
- increased glandular epithelial secretions
- stimulation of glycogen accumulation in stromal cell cytoplasm
- promotion of stromal vascularity (spiral arteries) and edema
76
Uterine curettage shows enlarged chorionic vili and avascular edematous stroma?
Findings consistent with a molar pregnance or spontaneous abortion
77
1st pharyngeal pouch derivatives?
Epithelium of middle ear and auditory tube
78
1st pharyngeal membrane derivative?
Tympanic membrane
79
1st pharyngeal groove derivative?
Epithelium of external ear canal
80
2nd pharyngeal pouch derivative?
Epithelium of palatine tonsil crypts
81
Fate of pharyngeal membranes 2, 3, and 4?
Obliterated
82
Fate of pharyngeal grooves 2, 3, and 4?
Obliterated
83
3rd pharyngeal pouch derivative?
Thymus, inferior parathyroid glands
84
4th pharyngeal pouch derivative?
Superior parathyroid glands, ultimobranchial body (those are the calcitonin-producing cells aka parafollicular aka C-cells of the thyroid)
85
Thymus and inferior parathyroid glands both derive from?
third pharyngeal pouch
86
What is sudden cardiac death?
Abrupt cessation of organized cardiac activity with hemodynamic collapse, causing an inability to maintain adequate tissue perfusion.
87
What is the most frequent mechanism of SCD?
Sudden Cardiac Death is most often caused by ventricular fibrillation, related to electrical instability due to lack of perfusion in the ischemic myocardium after acute MI.
88
biopsy findings in temporal arteritis? This pattern also seen in?
granulomatous inflammation of the media
| - also seen in Takayasu arteritis, affecting the aortic arch
89
artery biopsy shows segmental, transmural, necrotizing inflammation in medium to small-sized arteries? What type of vasculitis is this?
Polyarteritis nodosa - due to immune complex vasculitis
90
Younger, heavy cigarette smoker has a vasculitis?
Think thromboangiitis obliterans (Buerger's Disease)
91
Adapter molecule between mRNA codons and amino acids?
tRNA
92
How do the wrong amino acids end up in a growing polypeptide chain?
Erroneous amino acid/tRNA coupling by AA-tRNA synthetase leads to insertion of the wrong AA in a growing polypeptide chain
93
Histology of a Barr body?
condensed body of heavily methylated DNA at the periphery of cell nucleus of every autosomal cell in female body. They are reproduced and then faithfully deactivated when a cell replicates
94
How can females inherit X-linked conditions?
Skewed lionization of Barr Bodies can decrease the protection afforded by random deactivation of the extra X chromosome, leading to effectively an X-linked inheritance pattern of an X-linked disease, such as hemophilia
95
Which DNA residues are methylated?
Cytosine is converted to methylsytosine - along with deacetylated histones, leads to low levels of transcriptional activity
96
Influenza vaccine administered via injection is live or inactivated?
Inactivated
97
Influenza vaccine administered via nasal spray is live or inactivated?
Live-attenuated
98
Inactivated influenza vaccine works how?
Induces neutralizing antibodies against the hemagglutinin antigen of the selected viral strains -- immune response will therefore inhibit viral entry into cells on subsequent exposure to virus
99
Discuss MHC response to inactivated viral vaccines
Inactivated viral vaccines do not infect host cells and therefore do not enter the MHC class I antigen-processing pathway. Without this pathway to an immune response, there will be no CD8+ T cell response to actual infection in the future, as the CD8+ T cells have not been "prepped" to recognize MHC-presented antigen.
100
Natural killer cells respond to?
Virally infected cells and tumor cells. Unique in that they recognize stressed cells in the absence of antibodies or MHC indicators, and can respond quickly
101
mean, median, mode in negative skew?
mean
102
mean, median, mode in normal distribution
mean = median = mode
103
mean, median, mode in positive skew?
mean > median > mode
104
Where is the mean in a positively-skewed distribution?
In a positively skewed distribution, the most frequently occurring values are small (i.e., the mode is a small value). However, a few very large values in the tail pull the mean to a value larger than the mode.
105
Where does the median lie in any distribution?
Median lies between the mean and the mode, unless you have a "normal" distribution, in which case they are all the same value
106
In which direction does the mean shift in a skewed distribution?
The mean shifts in the direction of the skew, i.e., a negatively skewed distribution will have a mean that is shifted towards negative values
107
Strep infection sequelae despite antibiotics?
Even with antibiotic treatment, patient may still develop poststreptococcal glomerulonephritis
108
ARF associated only with?
Acute rheumatic fever only associated with strep pharyngitis, not skin infection as evidenced by impetigo
109
HMG-CoA Reductase?
rate-limiting enzyme in the cholesterol synthesis pathway
110
Why is estrogen included in OCP?
To improve the bleeding profile
111
What hormone is responsible for pregnancy prevention in all hormonal contraceptives?
Progestin - synthetic equivalent to pregesterone
112
How do hormonal contraceptives work?
Combined hormonal contraceptives exhibit systemic effects by suppressing GnRH in the hypothalamus, which decreases synthesis of the gonadotropins FSH and LH in the anterior pituitary. Because an LH spike is required to stimulate ovulation, ovulation is inhibited.
113
How does a copper IUD work?
Releases copper ions that elicit an inflammatory reaction in the uterus that is toxic to sperm and prevents fertilization
114
Patient with steroid requiring condition (like SLE) stops taking them?
Risk of adrenal crisis - long term glucocorticoids suppress the HPA, leading to bilateral adrenocortical atrophy.
115
Risks associated with second generation antipsychotic medications?
Associated with adverse metabolic effects such as weight gain, dyslipidemia, hyperglycemia, and increased risk of diabetes. Olanzapine and clozapine carry the greatest risk.
116
Good treatment for psychotic and mood disorders? Patient has crazy ideas, maybe, not just sad?
Olanzapine, a second-generation antipsychotic (SGA)
117
Newborns and Vitamin K? Potential scenario and fatal complication?
We give newborns vitamin K to prevent bleeding disorders of impaired clotting. In a homebirth, newborn probably doesn't get vitamin K injection. Fatal complication is intracranial hemorrhage. Look for signs of increased ICP.
118
Signs of ICP in a newborn?
altered mental status, enlarging head circumference/fontanelle, and downward-driven eyes.
119
Most effective anticoagulant for inactivating thrombin?
Unfractionated heparin. LMWH and other fancy heparin derivatives are too short to bind antithrombin and thrombin together.
120
Normal alkaline phosphatase levels in non-pregnant adults?
20-140 IU/L
121
High alkaline phosphatase levels suggest what?
Bile duct obstruction.
| Active bone formation, alk phos is a byproduct of osteoblast activity.
122
ALP is high. What test next?
High alkaline phosphatase suggests bile duct obstruction of bone growth. Check gamma glutamyltransferase activity, elevated in hepatobiliary disease.
123
Characteristics of Paget's Disease of the Bone?
Accelerated bone remodeling with eventual bony overgrowth. Environmental factors and gene mutations result in excessive RANK signalling and NF-kB activation. This leads to increased osteoclast differentiation and activity. Patient will have bone pain, increased alkaline phosphatase, and biopsy findings.
124
Biopsy findings show haphazardly oriented segments of lamellar bone with prominent cement lines?
Paget's Disease of the Bone, increased activity of osteoclasts
125
Feedback mechanism against iron overabsorption?
Iron is taken up by divalent metal transporter on the apical surface of enterocytes. Iron is then packaged into transferrin, which leaves traverses the basolateral surface of enterocytes via ferroportin. The transferrin receptor on hepatocytes controls endocytosis of transferrin into hepatocytes, and is regulated by HFE protein. Iron absorption and storage in the liver feeds back to regulate iron uptake. Mutations in HFE (most common cause) result in artificially low iron signal, triggering increased iron uptake by enterocytes and decreased hepcidin synthesis
126
Risks when body iron levels exceed 20 g?
triad of micronodular cirrhosis, diabetes mellitus, and skin pigmentation (bronze diabetes). Increased risk for hepatocellular carcinoma, CHF, and testicular atrophy/hypogonadism
127
Reaction formation in a psych patient?
Redirection of an unacceptable feeling to its opposite (i.e., paradoxical expression of affection instead of anger towards an individual)
128
Projection in a psych patient? Common cause?
Immature defense mechanism that involves misattributing one's own unconscious, undesired thoughts or feelints to another person who does not actually have them. Projection commonly occurs in patients who lack insight into their own motivations and feelings.
129
Describe superior mesenteric artery syndrome?
SMA leaves the aorta at the level of L1. The transverse portion of the duodenum lies horizontally at the level of L3. Normally, the SMA and the aorta form an approximately 45 degree angle. If this angle diminishes to less that 20 degrees, the transverse portion of the duodenum can get entrapped between the SMA and aorta, leading to symptoms of partial small bowel obstruction.
130
Concern if there are no bowel sounds after hyper-active bowel sounds?
Ruptured bowel
131
Concern if there are high-pitched bowel sounds?
Early bowel obstruction
132
Triggers for superior mesenteric artery syndrome?
This syndrome occurs when the aortomesenteric angle critically decreases, secondary to diminished mesenteric fat (think radical diet), pronounced lordosis, or surgical correction of scoliosis (the angles all get changed in these last two scenarios).
133
Effect of electrical stimulation of the hypoglossal nerve?
Increases the diameter of the oropharyngeal airway and decreases the frequency of apneic events.
134
Sudden deceleration and pivot on an extended knee? Useful anatomy knowledge?
Torn ACL. Starts on lateral femoral condyle, courses anteriorly and medially to insert on the anterior intercondylar area of the tibia. Prevents forward movement of the tibia relative to the femur (Lachman or anterior drawer test).
135
How to distinguish E. coli from Enterobacter cloacae?
Both are lactose-fermenting, gram negative rods. E. coli is also indole positive, which means it can convert tryptophan to indole.
136
Indole positive bacteria?
Can convert tryptophan to indole, like E. coli.
137
Heme synthesis occurs where?
First step and last three steps are in mitochondria, middle steps are in cytosol.
138
Right-sided colon cancer presentation?
Exophytic mass and presents with occult bleeding and symptoms of iron deficiency anemia.
139
Left-sided colon cancer presentation?
Infiltrate the intestinal wall and encircle the lumen, causing constipation and symptoms of intestinal obstruction.
140
Rectosigmoid involvement in colon cancer causes?
Hematochezia
141
Describe the replication cycle of Hepatitis B virus?
Partially double-stranded circular DNA molecule that replicates through reverse transcription. Double-stranded circular DNA serves as a template for transcription into an intermediate + single-stranded RNA. This RNA strand in turn serves as a template for both translation of viral proteins and reverse transcription into a single-stranded DNA intermediate, converted back into partially double-stranded DNA
142
Name three important mitochondrial syndromes?
1) Leber hereditary optic neuropathy --> leads to bilateral vision loss
2) Myoclonic epilepsy with ragged-red fibers --> myoclonic seizures and myopathy associated with exercise. Skeletal muscle biopsy shows ragged red fibers ("irregularly shaped")
3) Mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) --> Seizure disorder, stroke-like episodes, muscle weakness, increased serum lactate levels both post-exercise and at rest
143
How to calculate the number needed to treat (NNT)?
Calculate the NNT as 1 divided by the absolute risk reduction (ARR). So if test group has event rate of 1% and control group has event rate of 2.5%, the ARR is 1.5%. Dividing 0.015 into 1 gives 66.6, which must be rounded up to 67 as the number needed to treat.
144
Normal serum calcium levels?
8.5-10.2
145
Patient has hypercalcemia but no focal lytic bone lesions?
Suggests humoral hypercalcemia of malignancy, caused by secretion of parathyroid hormone-related protein (PTHrP). Calcium levels will be higher than those of primary hyperparathyroidism.
146
If a patient has hypercalcemia, what do you expect the PTH levels to be?
Low - calcium has a negative feedback on PTH secretion. If it is high, think malignancy. Also, consider ectopic production of PTHrP by a lung cancer.
147
Patient starts ACE inhibitor and then goes hypotensive. Why?
Patient had very high plasma renin activity, most likely resulting from volume depletion (excess diuresis) or heart failure.
148
Immature T lymphocyte cell surface markers?
Both CD4+ and CD8+ plus complete T Cell Receptor (TCR) or a pro-TCR
149
Inheritance pattern of achondroplasia? MoA?
Autosomal dominant inheritance, though advanced paternal age has something to do with it. Point mutation in fibroblast growth factor receptor 3 gene (FGFR3) causes exaggerated inhibition of chondrocyte proliferation, leading to prevention of endochondral ossification in the long bones. See shortened limbs, mid-face hypoplasia, and macrocephaly.
150
Chest tube placement and relevant anatomy?
4th or 5th intracostal space, mid-axillary line. Traverses through the serratus anterior muscle, intercostal muscles, and parietal pleura to reach the pleural cavity
151
Most common benign vascular tumor in children?
Capillary hemangioma, such as a strawberry (infantile) hemangioma. Bright-red, compressible plaques with sharply demarcated borders. Emerge early, regress by 5-8 years of age.
152
IV acyclovir side effect?
5-10% of patients receiving iv acyclovir experience nephrotoxicity. Renally excreted, when acyclovir concentration in the collecting duct exceeds its solubility, crystallization, crystalluria, and renal tubular damage may result. Treat with adequate hydration, slower infusion.
153
Name three Class III antiarrhythmic drugs?
Sotalol, amiodarone, dofetilide
154
MoA of Class III antiarrhythmic drugs?
Predominantly block potassium channels and inhibit the outward potassium currents during phase 3 of the cardiac action potential, thereby prolonging repolarization and total action potential duration
155
On histology specimen, significance of a binucleate or symmetric, bilobed cell? Origin of these cells and markers?
Think lymph node - Reed Sternberg cell --> Hodgekin Lymphoma, but not pathognomic
From B cells, all CD15+ and CD30+
156
microtubule inhibitors (drugs)
"-taxels" (paclitaxel et al.), vinca alkaloids (vincristine, vinblastine)
--> bind beta-tubulin to inhibit polymerization
157
normal central venous pressure?
2-8 mm Hg
158
normal pulmonary capillary wedge pressure?
4-12 mm Hg
159
penicillin allergy alternative?
NOT cephalosporins - 5-10% cross-over reaction
- -> go for macrolides for gram +
- -> go for azteronam (monobactam) for gram - rods
160
sinus venous drainage of CSF?
Superior sagittal sinus via arachnoid granules
161
patient with alpha-1-antitrypsin deficiency:
- lungs look like?
- liver looks like?
- resembles a condition due to?
- Increased AP diameter, flattened diaphragm, lung field lucency
- accumulation of misfolded alpha-1-antitrypsin in liver leads to liver cirrhosis and periodic acid-Schiff (PAS) positive globules
- "smoker's emphysema", though this is centriacinar, not panacinar
162
acetamenaphin toxicity MoA?
centrilobar (zone 3) necrosis and central vein
- highest [P450] and lowest [O2]
- actually the toxic metabolites that do the damage
- glutathione becomes depleted, then damage happens
163
AZT MoA?
No hydroxyl group on 3' carbon, so no 3' phosphate bond --> stop transcription
164
anion lost in vomiting? diarrhea? implications?
Lose H+ vomiting --> metabolic alkalosis
| Lose bicarbonate in diarrhea --> metabolic acidosis
165
B3 deficiency symptoms? B3 therapeutic use?
pellagra --> dermatitis, diarrhea, glossitis, dementia
Can be used to raise HDL and lower LDL/triglycerides
Think someone has high LDL and triglycerides, you prescribe, they come back a month later with complaints --> they overdid it on the B3
166
venous blood pH during anaerobic exercise?
decreased pH (acidic) from increased CO2 and production of lactic acid (anaerobic glycolysis)
167
Symptoms of lithium toxicity? sequelae?
confusion, N/V, dysarthria, lethargy, coarse hand tremors
| - Can lead to nephrogenic DI --> urine osmolarity and gravity decreased, serum osmolality and [Na+] increased
168
yellow crystals parallel to axis of polarization?
monosodium urate crystals; they are blue when perpendicular --> suggests gout
169
Calcium pyrophosphate dihydrate crystals shape? polarization?
pseudogout -- rhomboid crystals; blue when parallel to polarization, yellow when perpendicular
170
gout short and long-term treatment?
NSAID (indomethacin) for immediate pain relief - colchicine if NSAIDS not tolerated - and allopurinol long-term (xanthine oxidase inhibitor)
171
consequence of unmanaged gout?
Nephropathy - deposition in renal medullary interstitium
172
normal serum albumin levels?
3.5-5.5 g/dL
173
B symptoms followed by pulmonary edema, hypotension, and coagulopathy
Hanta virus - a - ssRNA bunya virus with a rodent reservoir, not arthropod
174
other Bunya virus illnesses?
California encephalitis and Rift Valley Fever and Crimean-Congo hemorrhagic fever
175
"stacked plate" cross-section of an organelle? function?
Golgi apparatus - protein modification, oligosaccharide tags - defect sends proteins/enzymes to wrong locations
176
post-transcriptional modifications of genes?
gene splicing --> alternate end products
| - addition of 5' cap and poly(A) tail
177
poly(A) tail does what/where?
polyadenylation of mRNA at 3' end --> important for nuclear export, transition, and stability of mRNA --> shortened over time, then mRNA is degraded
178
seminoma lymphatic spread?
paraaortic lymph nodes
179
tyrosinase function? significance?
Converts tyrosine to dihydroxyphenylalanine (DOPA). Rate-limiting step; defect means decreased melanin (i.e., albinism), decreased dopamine
180
IL-2 receptor monoclonal antibodies?
Basiliximab and daclizumab - immunosupressants to decrease CD8+ T cells for organ transplant
181
cells with no MHC I?
RBC --> MHC I only expressed on nucleated cells
182
What causes fasciculations? UMN or LMN?
LMN - thought to be residual release of ACh from degenerating nerve terminal at NMJ
183
diuretics that can induce metabolic alkalosis?
Hydrochlorothiazie and furosemide (inhibit Na+ uptake, deliver increased Na+ distally, loss of fluid without loss of bicarb, contraction alkalosis)
184
site of ACh synthesis in the brain?
Basal nucleus of Meynert
185
beta blocker effect on cardiac parameters? (5)
```
Increased end diastolic volume (more filling time)
Increased ejection time
Decreased BP
Decreased contractility
Decreased heart rate
```
186
Beta1 receptor location? effects? examples?
Heart and kidneys
- Heart --> increase heart rat
- Kidney --> stimulate renin release
187
Tear-drop shaped trophozoites with ventral sucking disk? Treatment?
Giardia lamblia; treat with metronidazole
188
Sequelae of pre-eclampsia? Control?
Seizure and increased risk of cerebral hemorrhage, thromboembolism, hypoxic encephalopathy
- treat with bed rest, control BP and prevent seizures with magnesium, deliver early
189
hypertension, proteinuria, pitting edema in pregnancy
This is not pre-eclampsia, think molar pregnancy. Leads to increased risk if choriocarcinoma and uterine rupture
190
S1 vertebra not completely fused? Associated pregnancy medication?
Spina bifida occulta. Yes, folate deficiency, but the testers will go after valproic acie --> anti-epileptic and mood stabilizer that is teratogenic
191
biomolecule responsible for eptic shock in N. gonorrhea?
Lipooligosaccharide, not LPS!
192
bone marrow aspirate shows macrophages engulfing RBCs? Details?
Hemophagocytic lymphohistiocytosis - multi-gene AR --> abnormal activation and profileration of lymphohistiocytes upregulate pro-inflammatory cytokines --> symptoms
193
action of secretin?
increase pancreatic and biliary bicarbonate secretion
194
aminoglycoside toxicities?
ototoxicity, nephrotoxicity, neruomuscular blockade
195
hemangioblastomas and renal cell carcinoma? mutation? inheritance?
Von Hippel-Lindau; deletion of VHL tupmor suppressor on 3p; AD inheritance
196
most common cause of inherited hypercoagulability in whites? how? another one?
Factor V Leiden --> mutant Factor V resists degredation by activated protein C
Can also be hypercoagulable due to protein C and S deficiencies --> increased Va and VIIIa activity
197
hemidesmosomes vs desmosomes
Hemidesmosomes --> present in basal cell plasma membrane, anchor epidermal basal cells to underlying extracellular matrix
Desmosomes --> intercellular connections in epidermal layer, no connection to basal layer
198
Dyspnea in a non-smoking, African American woman? Pathophysiology?
Think sarcoid -- look for other non-specific systemic involvement -- fever, fatigue, weight loss
Dysregulation of CD4+ Th cells
199
Sarcoid and 1-alpha-hydroxylase?
macrophages in granulomas express 1-alpha-hydroxylase inappropriately; Too much active Vitamin D --> hypercalcemia --> shortened QT and decreased PTH
200
treatment for Dressler syndrome? How to elicit symptoms?
Aspirin, NSAID, or corticosteroids; friction rub is louder if patient leans forward
201
Lactulose MoA?
acidifies colonic contents via digestion by colonic bacteria --> acidify and trap ammonia
202
Griseofulvin MoA?
Antifungal agent - binds alpha/beta tubulin dimers, disrupts spindle apparatus --> block mitotic anaphase
203
C7TR?
cystic fibrosis transport receptor on chromosome 7
204
ureidopenicillin property? Common example?
polar side chain --> enhanced penetration into gram neg, piperacillin is commonly used against Pseudomonas
205
Reiter Syndrome Triad?
can't see (conjunctivitis), can't pee, can't climb a tree (arthritis)
206
budding yeast in a macrophage on histology plus respiratory symptoms?
Histoplasma --> Ohio/Tennessee River Valley
207
Bones, Lung, and Skin histology finding?
BLAStomyces --> Southeast plus Great Lakes; see broad based buds
208
spherules on histology plus respiratory symptoms?
coccidiodes --> Desert Southwest, in soil
209
Captain's Wheel on histology?
paracoccidioides --> Latin America
210
endocarditis organisms in IV drug abusers?
1) Staph aureus and 2) Candida albicans (both normal skin flora)
3) Pseudomonas aeruginosa (water contaminant in adulterated street drugs)
211
hyphi branching patterns?
non-septate, 90 degrees in mucormycosis
| septate acute angles in aspergillus
212
treatment threshold to add steroids to treatment plan in pneumonia?
PaO2
213
Invasive fungal sinusitis organisms? Treatment?
```
Mucormycosis and Aspergillus
Triple treatment includes:
1) surgical debridement
2) stabilize electrolytes
3) Amphotericin B
```
214
fever and muscle weakness, perhaps after mild fever and diarrhea, especially in non-vaccinated/immigrating to US patient?
Polio virus -- fecal/oral transmission -- infects via Peyers patches -- leads to respiratory muscle failure, polyplegia
215
crescent-shaped blood cells on smear? complication? pathogen causing osteomyelitis in these patients?
Sickle Cell disease, risk of autosplenectomy --> increased susceptibility to encapsulated organisms
Osteomyelitis from salmonella (not S. aureus)
216
flora responsible for maintaining low vaginal pH? gram stain?
Lactobacilli: gram + facultative anaerobe
217
"spaghetti and meatballs" under microscopy? treatment?
Malassezia furfur infection, causes tinea versicolor; treat with selenium sulfide (selsun blue et al.)
218
suspected encephalitis , CT show focal, unilateral pathology in the temporal lobe? Treatment?
HSV-1 encephalitis; treat with acyclovir
219
Which vaccines promote cellular and humoral immunity? why?
Live, attenuated vaccine; weakened or non-virulent organism can enter cells to invoke cellular response (CD8 via MHC I)
220
potato agar or Regan-Lowe medium swab type?
isolate Bordatella pertussis; potato = Bordet-Gengou calcium alginate swab (cotton no good)
221
medium for Corynebacterium diphtheria?
Tellurite agar or Loffler's medium
222
STI with painless, bilateral inguinal lymphadopathy? What if it's painful?
Syphilis (T. pallidum) if painless
| LGV (C. trochamatis L1-L3) if painful
223
Cold symptoms or other URI followed up by persisten cough, especially in unvaccinated individual? Treatment?
Bordatella pertussis, treat with macrolides
224
S. aureus scalded skin syndrome MoA?
epidermolytic toxin A & B bind desmogelin in the desmosomes, aka "macula adherens" --> leads to bullous lesions and positive Nikolsky sign
225
Patient has positive Nikolsky sign?
This is when the top layers of skin slip away from the bottom layers when rubbed slightly, indicates scalded skin syndrome (S. aureus infection) or toxic epidermal necrolysis (pemphigus vulgarus)
226
cysts and coproantigen in stool? treatment?
giardiasis (Giardia lamblia); treat with metronidazole or tinidazole
227
stages of post-surgical septic arthritis induced by organism on joint replacement?
S. aureus;
3-12 months --> S. aureus, S. epidermidis, gram + aerobes
> 24 months --> hematogenous spread to joint
228
diarrhea with gradual onset, worsening to bloody and mucus over weeks? Secondary infection location? Surprising finding on CBC?
amebiasis, amebic colitis with Entamebahystolytica (or Crohn's disease, UC?)
secondary infection is in a liver abscess
CBC may show eosinophila (i.e., >7%)
229
fever, night sweats, and pneumonia with apparent consolidation localized to upper lobes/apex? Treatment and toxicities?
Relapsing or secondary TB infection - RIPE treatment and isonaizid for close contacts; hepato- and nephrotoxicities
230
viral trait leading to pandemics?
segmented genomes (i.e., influenza, rotavirus) that can swap huge parts to make a comletely new virus (antigenic shift versus drift)
231
HIV+ with specific visual field deficit, as opposed to generally poor vision? seizures?
Think toxoplasma gondii encephalitis. CMV uveitis is not field-specific
232
atypical lymphocytes in EBV infection?
T-cells --> non-spheroidal, excess cytoplasm --> even though EBV infects CD21+ B cells
233
dramatic hepatosplenomegaly and eosinophilia?
Schistosoma mansoni --> endemic in sub-saharan Africa, middle east, South America, Carribean
234
painful genital ulcer that bleeds when scraped; inguinal lymphadenopathy with possible rupture and purulent drainage; organism?
Chancroid --> due to Haemophilus ducreyi, a gram negative coccobacillus
235
Always Bring Polymerase Or Fail Replication? Also?
arena, bunya, paramyxo, orthomyxo, fila, and rhabdo viruses --> negative sense ssRNA, need RNA dependent RNA polymerase;
also Delta virus, aka HepD, a viral "satellite"
236
only double stranded RNA virus?
Reovirus (rotavirus and Colorado Tick disease)
237
Which virus predisposes to subsequent bacterial pneumonia? morphology?
Influenza, an enveloped, negative sense, ssRNA with 8 segments
238
stain for detecting mycolic acid?
acid-fast, aka Ziehl-Neelsen stain
| contains carbol fuchsin
239
non-typhoidal salmonella treatment?
supportive --> abx actually prolong the illness
240
Charcot triaqd? suggests?
Fever, jaundice, URQ pain
| -suggests cholangitis
241
Burkitt's Lymphoma genetics? Histology?
t(8;14) "starry sky" appearance, sheets of lymphocytes with interspersed macrophages
242
positive cross-rsn of antibody to Proteus antigen?
Rickettsia reckettsii
243
Screening and sensitivity test for HIV?
ELISA followed by Western Blot
- ELISA is sensitive, but non-specific
- Western Blot is a protein test with high specificity
244
viral-associated hemorrhagic cystitis?
Adenovirus; or BK in immunocompromised (organ/bone marrow transplant)
245
Polio virus paralysis MoA?
preferential infection of anterior horn neurons
246
Influenza predisposes to bacterial pneumonia MoA? which bugs?
edema of epithelial cells in URT decreases ciliary effectiveness, allows bacterial invasion; Think S. aureus, S. pneumo, H. influenza
247
Influenza antigenic shift MoA?
Co-infection in a single cell with different strains (i.e., A & B) leads to segment reassortment
248
Treat RSV with?
Paviluzimab --> monoclonal antibody against Fusion ("F") protein
249
necrosis of infected brain tissue, means what for CSF, confirm diagnosis with?
lots of RBCs in CSF --> encephalitis/hemorrhage; confirm with PCR
250
How to differentiate bacterial vs fungal meningitis in CSF?
bacterial will have increased PMNs
| fungal (and viral) will have increased leukocytes
251
Extraintestinal complication of UC? Symptoms?
Primary sclerosing cholangitis - 70% overlap of PSC with UC, but only 4% of UC patients have PSC (one way connection)
Symptoms include itchiness, fatigue, past history of colon resection scleral icterus
252
metal toxicity that manifests as intention tremor, nephrotoxic, personality changes? Treatment?
mercury poisoning; treat with chelation therapy by dimercaprol
253
child with anemia (pale, tired, CBC) and positive Coombs test and warm agglutinin test? treatment in children? what about treatment in adults?
autoimmune hemolytic anemia (AHIA); treat with corticosteroids --> block immne destruction of erythrocytes (esp. IgG) via Fc receptor; in adults only, use IVIG
254
sequelae of malignant hyperthermia? how to see each?
DIC - check D-dimers
rhabdomyolysis - check creatinine (increased) and hyperphosphatemia (impaired renal function)
dysrhythmias
hypotension
255
Biostats - you have the sensitivity and specificity of some test, say specificity is 95%. In any group of patients without the condition, what are the chances of testing positive?
The chance for any individual to test positive even without the condition is dictated by the specificity, which in this case suggest a 5% false positive rate. So, for any one person, there is a 5% chance of false positive. For multiple people taking the test, the tests are independent, so combining probabilities is multiplicative. Chance of positive is 0.95^n for a positive test in n people, and (1 - 0.95^n) for negative test in n people.
256
Very first hemoglobin formed by embryo in uterus? Then?
```
Gower - two zeta and two epsilon chains, produced in the embryonic yolk sac
Hemoglobin F (two alpha, two gamma) starts within a few weeks from the liver)
```
257
Sequence that serves as the initiator of translation in eukaryotic cells?
Kozak consensus sequence
258
Patient with beta thal -- type of anemia? mechanism of damage?
Hypochromic, microcytic anemia due to decreased beta globin chain synthesis. Unpaired alpha chains precipitate within red cells and cause membrane damage, leading to ineffective erythropoiesis and extravascular hemolysis
259
renal transplant patient follow up concern months to years later?
chronic renal allograft rejection manifests months to years after transplantation and presents with worsening hypertension and a slowly progressive rise in serum creatinine, mediated by a chronic, indirect, immune response against donor alloantigens and results in obliterative intimal thickening, tubular atrophy, and interstitial fibrosis.
260
patient has vision impairment (maybe lens opacities) and large amounts of galactose in the urine? Enzyme deficiency? Treatment?
Sounds like galactokinase deficiency, a form of galactosemia that causes a benign disorder characterized by cataracts without hepatocellular manifestations; Patient lacks Aldose reductase; treat with dietary restriction of lactose
261
Aldolase B deficiency?
hereditary fructose intolerance
262
beta-galactosidase deficiency?
lysosomal enzyme responsible for breakdown of glycosaminoglycans. Deficiency results in accumulation of keratin sulfate within lysosomes and manifests with short stature, normal intelligence, atlantoaxial instability and valvular heart disease
263
Acute stress disorder vs panic disorder?
Acute stress disorder involves exposure to a traumatic event followed by development of characteristic symptoms lasting from 3 days to 1 month. Panic disorder requires recurrent, unexpected panic attacks, typically reaching a peak within minutes and followed by persistent concern about additional attacks (pt. "doesn't know when it might happen again"), leads to avoidance behaviors
264
Preferred first-line therapy treating delirium tremens?
Long-acting benzos with active metabolites, such as diazepam or chlordiazepoxide - preferred because of "self-tapering" effects
265
Treatment of DT in patients with liver disease?
Non-active metabolite benzos, such as lorazepam, oxazepam, or temazepam
266
Patient is in shock. Epinephrine effect on alpha 1, beta 1, and beta 2 receptors?
alpha 1 - counteracts vasodilatation of cutaneous and viscera vasculature, thus increasing blood pressure
beta 1 - increase in cardiac contractility and cardiac output
beta 2 - bronchodilatation
267
Patient with hypertension suffers from hearing loss. Why?
Loop diuretics (furosemide, torsemide, bumetanide) inhibit Na/K/2Cl symporters in the ascending limb of the loop of Henle. Inhibition of similar symporters in the inner ear is believed to cause ototoxicity, especially with higher doses and on preexisting CKD
268
iatrogenic SLE medications?
Hydralazine, Procainamide, Isoniazid, Minocycline, Quinidine
(and then there's SHIPPE from First AID)
Hydralazine and Procainamide are the highest risk
269
Antibody that is not seen in DILE?
Drug-induced Lupus Erythematosus - don't find dsDNA antibodies, though anti-nuclear is normal.
270
Supracondylar humeral fracture concern on displacement (2 outcomes)?
Anterolateral displacement --> radial nerve injury
| Anteromedial displacement --> median nerve/brachial artery injury
271
pulseless hand after arm fracture?
Worry about brachial artery
272
HIV gp120 and gp41?
These are the proteins that mediate virion attachment to host cells. They derive from a single env gp160 protein that is proteolytically cleaved within the er and Golgi apparatus
273
Tell me about calcineurin?
Calcineurin is an essential protein in the activation of interleukin-2, hwich promotes the growth and differentiation of T cells.
274
How to suppress calcineurin?
cyclosporine and tacrolimus work as immunosuppressants by inhibiting calcineurin activation
275
What are Janeway lesions?
nontender, macular, and erythematous lesions typically located on the palms and soles, result of septic embolization from valvular vegetations.
276
How to calculate bioavailability of a drug?
Due IV infusion and oral ingestion, measure serum concentration over time. Bioavailability is calculated as area under the oral curve divided by area under the IV curve
277
Complication when someone receives massive blood transfusion?
Hypocalcemia - patient might report parasthesias. Prior to storage, whole blood is generally mixed with solutions containing citrate anticoagulant. Packed cells derived from these whole blood collections also contain citrate, which chelates serum calcium
278
What are neurophysins?
Proteins that are involved in posttranslational hormone processing and stabilization during axonal transport of vasopressin and oxytocin in neurosecretory vesicles.
279
New onset odynophagia in the setting of chronic gastroesophageal reflux disease? Next test?
(Pain with swallowing) Indicates presence of erosive esophagitis, formation of an ulcer. Confirm with upper endoscopy
280
Reactive arthritis HLA?
B27 allele
281
Behaviour problems, food-seeking behavior, incomplete sexual development, cognitive disability; specific loss?
Prader-Willi Syndrome due to loss of paternally inherited genes on 15q11-13
282
Genetic anomaly in PWS (3)?
Chromosome 15 - the maternal allele is silenced, only the paternal allele should be expressed. This is a problem if:
1) Paternal deletion (maternal allele is silent - 70% of cases)
2) Maternal UPD (both copies are silenced - 25%)
3) Imprinting defect (5%)
283
gene imprinting does what?
DNA methylation and histone methylation without altering gene sequence --> silence the gene
284
PWS and no genetic abnormalities on FISH?
No deletion detected, means maternal UPD
285
neonatal hypotonia, small hands/feet?
Consider PWS
286
Genetic anomaly in Angelman Syndrome? (3)
Chromosome 15 - Paternal allele is silenced, only maternal allele should be expressed. Problem if:
1) Maternal deletion (paternal allele is silent - most common)
2) Paternal UPD (both copies are silenced)
3) Translocation (least common)
287
Happy demeanor, easily excitable, flapping hand movements, short attention span; specific loss?
Angelman Syndrome ("happy puppet" pejorative, no longer used) due to loss of maternally inherited genes on 15q11-13
288
neurophys of Angelman?
Abnormal EEG, three distinct interictal patterns, most commonly large amplitude 2-3 Hz rhythm in prefrontal leads
-deficit of neuronal function, not form
289
Celiac disease genetic component?
HLA DQ2 and DQ8 genotypes
290
rash on extensor surfaces and diarrhea? Cause of the rash?
Consider Celiac disease. Villous blunting seen on endoscopy, dermatitis herpetiformis on skin. Rash is caused by cross-reactivity of anti-gliadin IgA antibodies with transglutaminase at the dermal basement membrane
291
skin layer where calluses form?
Most superficial layer - the stratum corneum
292
Stratum corneum regenerated by?
Continuous process of shedding epithelium (15-20 layers thick) and replacement by mitotic activity in the stratum basale and stratum spinosum
293
layers of the epidermis (5)?
Strata corneum, luciden, granulosum, spinosum, basale (superficial to deep)
294
Hey, look at those ovaries! They're full of cysts?
PCOS - they have clever ways of showing you the ovaries without describing the symptoms normally associated with PCOS - for instance, prophylactic oophorectomy over cancer concerns
295
Clinical features of PCOS (4)?
1) Androgen excess --> hirsutism, acne, alopecia
2) Ovarian dysfunction --> menstrual irregularity, cysts
3) Insulin resistance --> Acanthosis nigricans, metabolic syndrome
4) Obesity
296
PCOS treatment?
weight loss, hormonal contraceptives, metformin for diabetes
297
endocrine cause of PCOS?
elevated levels of LH and hyperresponsiveness to LH leads to increased androgen production (i.e., increased testosterone)
298
testosterone role in PCOS?
testosterone inhibits process by which a single follicle becomes dominant --> enlargement of multiple, small follicles --> cystic progression
299
enzyme deficiency in Lesch-Nyhan? leads to? inheritance? lab test?
deficient hypoxanthine-guanine phosphoribosyltransferase (HGPRT); leads to decreased purine salvage and consequent increase in purine synthesis; X-linked inheritance; on labs, will see hyperuricemia, hyperuricuria
300
Child with gout, dystonia (involuntary movement), self-mutilating behavior, mild intellectual disability?
Lesch-Nyhan
301
"frost" on skin under diaper? treatment?
hyperuricemia --> suggestive of Lesch-Nyhan
| treat with allopurinol for symptoms of gout and urolithiasis, but this won't help neuro sx
302
inhibit 30s ribosomal subunit?
tetracyclines and aminoglycosides
303
inhibit 50s ribosomal subunit?
macrolides and chloramphenicol
304
regulator protein that determines cellular differentiation?
transcription factors
305
direct muscarinic cholinergic agonist? Common uses?
pilocarpine (among others, certainly); used in the treatment of chronic open-angle glaucoma and acute angle-closure glaucoma for over 100 years. It acts on a subtype of muscarinic receptor (M3) found on the iris sphincter muscle, causing the muscle to contract -resulting in pupil constriction (miosis). Pilocarpine also acts on the ciliary muscle and causes it to contract. When the ciliary muscle contracts, it opens the trabecular meshwork through increased tension on the scleral spur. This action facilitates the rate that aqueous humor leaves the eye to decrease intraocular pressure
306
Patient has sx consistent with pernicious anemia (B12 deficiency). What's up, what's down?
Remember effects of chronic gastritis: Hypochlorhydria (decreased acid) triggers increased gastrin release, but there is insufficient mucosa receiving the signal (feedback problem). Less acid means less secretin needed to counteract acid in the duodenum. Intrinsic factor also decreased.
307
History of auto-immune thyroiditis plus anemia symptoms?
Consider gastritis --> another autoimmune disorder that destroys gastric mucosa
308
Distinguish hydrocele from varicocele?
transillumination test (shine pen light through scrotum)
- swollen veins of pampiniform plexus do not transilluminate --> varicocele
- accumulation of peritoneal fluid between the parietal and visceral layers of the tunica vaginalis does transilluminate --> hydrocele
- both can reduce with patient in supine position
309
velvety, hyperpigmented plaques? When benign, when malignant?
Acanthosis Nigricans -- benign when associated with insulin resistance or diabetes; rapid onset or expansion is suggestive of malignancy in lungs or GI
310
long-term medication after valve replacement?
anticoagulate with coumadin (Warfarin)
311
Leuprolide indication and MoA?
Used to treat prostate cancer via androgen deprivation; Leuprolide is a GnRH analog that when given continuously (non-pulsatile) inhibitis FSH/LH release --> decrease testosterone synthesis
312
melanocyte embryonic precursor?
cells of the neural crest
313
DiGeorge embryologic structures?
```
hypoplastic thymus (absent thymic shadow)
absent parathyroids (hypocalcemia --> seizures)
defects in heart and great vessels (ToF, arteriosus, arch)
```
314
Naive mature B cells produce which immunoglobulin? Then what?
Produce both IgM and IgD with identical VDJ (antigen-binding) regions. Isotype switching to get IgG, IgA, IgE
315
key site of DNA methylation to stifle transcription?
cytosine-guanine dinucleotide repeats (CpGs) in the promoter region are preferentially methylated as part of epigenetic code --> prevents transcription factor binding of the promoter region
316
lysosome with "wrinkled tissue paper" appearance?
Gaucher's Disease; decreased beta-glucocerebrosidase
317
Second messenger for natriuretic peptides and nitric oxide?
cGMP --> activates protein kinase C
318
Second messenger for Gq? Which receptors?
signal via the phospatidylinositol 2nd messenger system --> activate phospholipase C, which releases IP3 and DAG from cell membranes --> increased intracellular Ca++ --> smooth muscle contraction;
Found in alpha-1, M1, M3, H1, V1 receptors
319
monoclonal antibody against TNF-alpha? clinical use? Alternative treatment?
infliximab; use in setting of inflammatory autoimmune conditions such as RA, Crohn's, ankyl0osing spondylitis, psoriasis; Etanercept is a recombinant TNF receptor fusion protein that acts as an inhibitor
320
umbilical vein/IVC connector? becomes?
Ductus venosus --> ligamentum venosum in adults
321
"broom-like" appearance on silverstain? Earler problem was? Tx?
Aspergillus fumigatus - septate hyphae with asexual fruiting bodies called conidiophores, look like a witch's broom on silver stain; A. fumigatus likes TB cavities, so note + PPD or history of TB; treat fungus ball of aspergillus via surgical excision
322
uterus didelphys and hypoplastic (short) digits? code for didelphys?
Hand-Foot-Genital syndrome, indicates HOXA13 (homeobox) gene mutation; longitudinal septum and dual cervix discovered after miscarriage is code for uterus didelphys
323
Normal, healthy person taking vitamin D lab findings?
Increased serum Ca++ and serum phosphate
| Decreased PTH
324
MUDPILES?
Methanol, Uremia, DKA, Propylene glycol/Paraldehycde, Isonaizid/Iron, Lactic acidosis, Ethylene glycol, salicylates
325
flank pain, gross hematuria, oliguria, high anion gap metabolic acidosis?
Suggests ethylene glycol poisoning --> metabolyzed to glycolate --> ATN --> see calcium oxalate crystals, + birefringent, look like envelopes
326
maxillary sinus drains via?
semilunar hiatus of middle nasal meatus
327
sinus most frequently infected? why?
maxillary sinus, poor drainage due to cilia fighting gravity
328
where is the body's internal clock?
suprachiasmatic nuclues (not supraoptic, that makes ADH and oxytocin)
329
anemia, opportunistic infection, and sudden bleeding irregularities? Examples of each?
acute leukemia - sudden exercise intolerance, candida overgrowth, gingival bleeding, retinal hemorrhage
330
smear has neutrophils with granules?
Those are actually eosinophils --> eosinophilia
331
splenic finding in chronic alcohol abuse? treatment?
splenomegaly, manifests as expansion of red pulp; due to portal hypertension (splenic vein hooks into portal venous system); octreotide (somatostatin analog) used to relieve portal hypertension by vasoconstriction of the splanchnic artery
