mixed deck 04/13

Question 1

Cricothyrotomy

Answer 1

• place the tube between the cricoid and the thyroid cartialages and requires an incision through the following structures:
  1. skin
  2. superficial cervical fascia (including subcutaenous fat and platysma muscle)
  3. investing and pretracheal layers of the deep cervical fascia
  4. cricothyroid membrane

Question 2

Ethambutol

Answer 2

-treatment for M. tuberculosis and atypical mycobacterial infections

side effects:
-decreased visual acuity, central scotoma, and or color-blindness (reversible)

Question 3

Fenoldopam

Answer 3

• the only intravenous agent that improved renal perfusion while it lowers blood pressure
• it is a benazepine derivative of DA but it is SELECTIVE D1-receptor agonist (so no effect on alpha or beta)
• recall DA –> AC–> cAMP–> vasodilation in arterial beds especially RENAL, MESENTERIC, and CORONARY beds.
• decrease in systemic vascular resistance (lowers BP)
• improve renal perfusion

Question 4

scarlett fever rash

Answer 4

• after 1-2 days rash appears on the neck, armpits and groin that subsequently generalizes to the rest of the body.
• the rash begins as scarlet spots or blotches, giving a boiled lobster appearence
• as the rash progresses and becomes more widespread, it begins to resemble a sunburn with goose pimples “sand paper rash”
• the cheeks commonly appear flushes, giving the area around the mouth a pale appearence in comparison (circumoral pallor)
• towards the end of the first week, desquamation begins and is most pronounced in the armpits, groin, and tips of the fingers and toes

Question 5

cleft lip

Answer 5

-when the maxillary prominences fail to properly fuse with the intermaxiallary segments (formed by the fusion of two medial nasal promineses) during early development.

Question 6

cleft palate

Answer 6

results when the palatine shelves of the maxillary prominence fail to properly fuse with one another or with the primary palate

Question 7

Pure red cell aplasia (PRCA)

Answer 7

• a rare form of marrow failure characterized by severe hypoplasia of marrow erythroid elements in the setting of nromal granulopoiesis and thrombopoiesis.
• inhibition of erythropoietic precursors and progenitors by IgG autoantibodies or cytotoxic T lymphocytes
• assoc with immune system disease such as thymomas and lymphocytic leukemias.
• also assoc with parvovirus B19 infection.

Question 8

Mucormycosis:
mucur, rhizopus, absidia
-they form broad, nonseptate hyphae that branch at wide often 90 degreen angles (mold only)

Answer 8

• assoc with diabetic ketoacidosis and underlying immunosupression (transplant, leukemia etc)
• facial and periorbital pain, headache, and purulent nasal discharge. The fungi proliferates in the walls of blood vessels and causes necrosis of the corresponding tissue –> black eschar may be seen on the palate or nasal turbinates

Question 9

Hyperplastic arteriolosclerosis

Answer 9

• in renal arterioles can result from and perpetuate malignant HTN. The pathological lesion is an onion-like concentric thickening of arteriolar walls in the renal vasculature and elsewhere.
• the stenosis decreases the glomerular perfusion and GFR, thus activating the renin-angiotensin-aldosterone system – viscious cycle

Question 10

Acute viral hepatitis

Answer 10

• low grade fever, anorexia, nasuea, dark colored urine, and RUQ tenderness
• diffuse balooning degernation (hepatocyte swelling), mononucelar cell infiltrates and councilman bodies (eosinophilic apoptotic hepatocytes) are seen histologically).

Question 11

motion sickness treatment

Answer 11

• the muscarnin M1 and histamic H1 pathways are sitmulation resulting in nausea and vomiting of motion sickeness
• meclizine, dimenhydrinate are first generation antihistaminic drugs

side effects of antimuscarinics: blurry vision, dry mouth, palpitations, urinary retention and constipation.

Question 12

lower border of the lung is located how many intercoastal spaces above the respective pleural border?

Answer 12

two intercoastal spaces.
-thoracentesis therefor should be performed betwen 5th and 7th ribs along the midclavicular line, the 7th and 9th ribs along the mid axillary line and the 9th and 11th ribs along the paravertebral line

Question 13

Lower bord of the right pleura is at what rib for
midclavicular line
midxillary line
paravertebral line

Answer 13

midclaviular: 7th rib
midaxxilary: upper border of 10th rib
paravertebral line: 12th rib

Question 14

the lower border of the pleura of the left lung is at what rib for the
midclavicular, midaxillary and paravertebral lines?

Answer 14

midclavicular: 7th rib
midaxillary: lower border of the 10th rib
paravertebral line: 12 rib

remember the lung is isually located two intercoastal spaces above the respective pleural border

Question 15

methadone

Answer 15

• heorin addiciton
• mu receptor
• long acting

Question 16

isoniazid is structurally similiar to pyridoxine (vitamin B6)

Answer 16

• this antibiotic increases the urinary excretion of pyridoxine
• competes for vitamin B6-binding sites, leading to defective synthesis of neurotransmitters like GABA
• isoniazid-induced neuropathy can usally be preventd with pyridoxine supplementation

Question 17

Tumor cells

human multidrug resistant gene MDR1

Answer 17

the protype product of this gene is P-glycoprotein, a transmembrane protein that functions as an ATP-dependant efflux pump
-in tumor cels, this ATP-poweed transmembrane pump protein actively removes chemotherapeutic agents, particularly hydrophobic agents like antracyclines

Question 18

Cytochrome P450 monooxygenanses

Answer 18

• present in hepatic microsomes and the ER of other tissues
• metabolizes steroids, alcohol, toxins and other forein substances by rendering them soluble and easer to excrete
• hoever metabolic processing also converts pro-carcinogens into carcinogens –> mutations
• ex of a carcinogen for lung cancer is benz (o)pyrene

Question 19

oral metronidazone can cause disulfaram like effects when combined with

Answer 19

alcohol

- it is used to treat giardiasis, trichomonas vaginitis and bacterial vaginosis

Question 20

first-dose hypotension can be a potential limiting factor when initiating ACE inhibitors

Answer 20

predisposing risk :
-hyponatremia, hypovolemia secondary to diuretics, low baseline blood pressure, high renin or aldosterone levels, renal impairment and heart failure. examples thiazide and loop diuretics

Question 21

Charcot-bouchard pseudoaneurysms

Answer 21

assoct. HTN
Location: small arteries that perfuse the basal ganglia and internal capsule
size: <1mm
Result of rupture: intracerepbral hemorrhage in the areas of basal ganglia, internal capsule,thalamus and pons
symptoms of rupture:
sudden onset of focal deficits

Question 22

Glucagonomas

Answer 22

• rare pancreatic tumors
• necrolytic migratory erythema, an elevated erythematous rash typically affecting the groin area
• hyperglycemia, stomatitis, cheilosis and abdominal pain

Question 23

osler-weber-rendu syndrom

Answer 23

• hereditary hemorrhagic telangiectasia
• autosomal domiant condition marked by the presence of telangiectasias in the skin as well as the mucous membranes of the lips, ornasopharynx, respiratory tracts, GI tract, and urinary tract.
• rupture may cause epistaxis, GI beeding or hematuria

Question 24

meconium ileus

Answer 24

• the intraoperative finding of an inspissated green mass suggests that the distal ileum has been obstructed by dehrdrated meconium.
• abnormalities in Cl, Na, water transport by the ductal epithelium of the intestinal mucous glands cause isotonic dehydration of the lumen contents

Question 25

Rb tumor supressor gene is located on chromosome 13g14

Answer 25

Rb protein is active when hypophosphorylate in its active state is prevents cell cycle to proceed -inactive state is hyperphophoylated, this allows the cell cycle to proceed through thr g1-S checkpoint.

Question 26

benign prostatic hyperpasia leads to intermittent bladder outlet obstruction and overflow incontience.

Answer 26

- Urinary retntion results in increased pressure into the UT and resultant reflux nephropathy. Ultimately, hydronephrosis and renal interstitial atrophy and scarring ensue. - the condition should be promptly treated, as prolonged obstruction can cause permanent damage and chronic renal failure.

Question 27

Renal papillary necrosis, which can be caused by a number of systemic conditions associated with ischemia

Answer 27

1. sickle cell disease or trait ---> sicklying causes obstruction of small kidney vessles 2. analgesic nephropathy -- decrease prostaglandin syntheiss, inhibit renal blood flow 3. DM - non-enzymatic gylcosylation causes changes in vascular walls, leading to compromised renal vasculature 4. acute pyelonephritis and UT obstruction --> edematous interstitium of the pyelonephritic kidney compresses the medullary vasculature, thus predisposing the patient to ischemia.

Question 28

Vagus nerve on the lung

Answer 28

- vagus nerve efferent activity on bronchial smooth muscle is constriction (recall B2 sympathetic causes dilation) - this is mediated by M3 receptors - M3 receptors of mucous glands in the bronchial submucusa increase secretions - thus increased vagal stimulation increases bronchoconstriction and secretion leading to incease airflow resistance and therefor increase work of breathing

Question 29

Creutzfeldt-jakob disease

Answer 29

prion protein PrP is normally found in neurons and has an alpha helical structure - if the a-helix is converted to a b-pleated sheet then the protein cannot be broken-down - accumulates in gray matter - the gray matter undergoes spongiform change - vacuoles form within the cytoplasm of neurons and neutrophils - later they grow bigger and form cysts

Question 30

Integrins

Answer 30

-are a family of transmembrane protein receptors that interact with the extracellular matrix by binding to collagen, fibronectin and laminin.

Question 31

25-30% of individuals have colonization of staph and or MRSA where?

Answer 31

-nasopharynx | anterior nares

Question 32

alpha -1- receptor affects on eyes

Answer 32

pupillary dilator mucle contracts whichs caused dilation of the pupil (mydriasis) ex) ophtalmic preparation of phenylephrine

Question 33

Beta 2 agonist acitivity of uterine contractions

Answer 33

- agonist leads to uterine relaxation, an effect called tocolysis, which is used in obstetrics to defer premature labor. ex) ritodrine and terbutaline

Question 34

Macrolides inhbit CP450 - erythromycin - clarithromycin but not azithromycin

Answer 34

-so drugs that are normally metabolized by the liver will last longer is used in conjunction with a marcrolides examples are statins

Question 35

Nonnucleoside reverse transcriptase inhibitors NNRT | nevirapine, efavirenz, delavirdine

Answer 35

-antriretroviral drugs do not require activation via intracellular phophorylation

Question 36

etoposide

Answer 36

- chemotherapeutic agent that inhibits the sealing activity of topoisomerase II - treatment will cause chromosomal breaks to accumulate in divide cells -->cell death

Question 37

both hep B and C increase risk for HCC

Answer 37

butttt hep B virus integrates its DNA into the host genome, thereby elevating the risk of HCC

Question 38

Urine discharge from the umbilicus

Answer 38

-the urachus is a remnant of the allantois that connects the bladder with the yolk sac during fetal development. Failure of the urachus to obliterate by birth results in patent urachus

Question 39

Fatty streaks

Answer 39

- earlierst lesion of atherosclerosis and are present in all individuals after age of 10 - they are composed of intimal, lipid filled foam cells, derived from macrophages and SMC that have engulfed lipoproteins

Question 40

chronic cholestasis from viliary obstruction

Answer 40

-cause fat soluble vitamin malabsorption | like vitamin A deficiency

Question 41

frequency sounds low and high heard best at?

Answer 41

- low frequency sound is best detected at the apex of the cochlear near the helicotrema - high freqency sound is best detected at the base of the cochlear near the oval and round windows