Longitudinal mucosal tears at the GE junction due to what mechanism?
Mallory-Weiss tears due to increased abdominal pressure (e.g. vomiting, retching, hiatal hernias)
Urease breaks down urea into?
CO2 and NH3.
MoA of Zenker's diverticulum?
Cricopharyngeal motor dysfunction: diminished relaxation of pharyngeal muscles when you swallow. Increased intraluminal pressure backflow causes mucosa to herniate at a point of muscle weakness.
False diverticulum: only mucosa herniates
What does southwestern blotting detect and type of probe?
DNA-binding protein (e.g. c-jun and c-Fos) and ds DNA antibodies.
Intraabdominal abscess organisms?
Anaerobes: B. fragilis and E.coli
Where does the pentose phosphate pathway occur?
Mechanism of acute cholecystitis?
Due to obstruction of the gallbladder neck or cystic duct. Stones disrupt the mucus layer, prostaglandins are released and hypomotility occurs. Increased pressure in gallbladder causes ischemia = necrosis prone to bacterial inflammation.
Ketones yield energy when they are converted to acetyl coA. What two tissues cannot use them?
1. RBCs - dont have mitochondria
2. Hepatocytes - dont have succinyl-coA-acetoactate coA to convert acetoacetate to acetoacetyl coA.
How can Hep A be inactivated?
boiling for 1 min
Bioavailability of a drug IV? Bioavailability of a drug orally?
<1 as affected by gastric secretions, food, saliva, absorption, metabolism by liver
F = area under drug given orally/area under drug given IV
If not equal rates: F = area of oral drug x IV dose/area of IV drug x oral dose
Increased NH3 in the gut, cannot enter liver through portal vein to detoxify into urea due to liver damage - decreased levels of BUN
MoA of cholestrol stone in a preggo?
Estrogen upregulates HmG-coA reductase acitvity causes an increase in cholestrol.
Progesterone decreases bile acid secretion and slows gallbladder emptying. More cholestrol than bile and/or decreased motility forms stones.
mcc of gallbladder hypomotility?
vagal stimuation; triggered by the thought, sight, smell, and taste of food.
Triggered by food and distention of the stomach
Inhibits acid secretion
1) Ileum and colon release peptide YY - binds to endocrine, histamine-containing cells known as ECL (enterochromaffin cells)
Enzyme promoting colonic adenoma development?
Long term treatment to help for peptic ulcer dz?
Antibiotics if cause by H.pylori.
MoA of hemachromatosis?
HFE gene encodes an HLA class I molecule that impairs iron absorption from the GI tract