Shit - GIT UWorld

Question 1

Niacin main role and toxicity

Answer 1

Raises HDL (also lowers VLDL and TG synthesis)
Toxicity = flushing, hyperuricemia (ppt gout), hyperglycemia (acanthosis nigracans), hepatitis

Question 2

Mechanism of base exception repair

Answer 2

Glycosylase recognizes deaminated base and removes it
Endonuclease and lyase remove the remaining sugar-Phosphate part
Polymerase puts new base in
ligase seals it

Question 3

Gastrin on parietal cells

Answer 3

Secrete acid

also TROPHIC = parietal cell hyperplasia (seen in ZE)

Question 4

PPT factors of SMA syndrome

Answer 4

Anything that causes decreased mesenteric fat (drops the angle) i.e. catabolism, bed rest
Also scoliosis correction

Question 5

Superficial inguinal nodes drain:

Answer 5

all skin below bellybutton except posterior calf (popliteal)

Question 6

Arsenic poisoning s/s and Rx

Answer 6

s/s = stomach pain, vomiting, delerium, GARLIC breath

Rx = Dimercaprol (which is nephrotoxic and hypertensive)

Question 7

Cholestyramine AE

Answer 7

increased TAG and VLDL synthesis
Increased cholesterol content of bile so cholesterol stones
Decreases statin absorption (give 4 hrs apart)

Question 8

Oxyphil histo

Answer 8

Eosinophils in upper glandular area of mucosa

Question 9

Signs of poor prognosis in liver failure

Answer 9

Prolonged PT, low albumin, high bilirubin

[indicate liver function]

Question 10

CREST esophagus shit

Answer 10

replace muscle with fibrosis –> dilated LES –> reflux -> barretts –> ACA

Esophageal hypomotility

Question 11

TZDs mechanism

Answer 11

binds nuclear receptor PPAR-g to increase adiponektin levels to decrease insulin resistance

Question 12

Pancreatic pseudocyst lined by; found where

Answer 12

granulation tissue and fibroblasts [real cysts = epithelium]

MC in lesser sac; boarders are stomach (ant), transverse colon, and duodenum

Question 13

NFKB role in inflammation

Answer 13

cytokine production

Question 14

Types of esophagitis and appearance

Answer 14

Eosinophilic = eosinophils, strictures
Reflux = metaplasia
Candida = plaques
CMV = linear ulcers
HSV = punched-out ulcers
Chemical ingestion

Question 15

colonic diverticula = what kind of diverticulum

Answer 15

pulsion

Question 16

Causes of acute pancreatitis

Answer 16

GET SHMASHED
[gallstones, ethanol, trauma, surgery, hypertriglyceridemia, mumps (coxsakie B and myco pneumo), Autoimmune, Scorpion sting, Hypercalcemia, ERCP, Drugs (sulfa, azathioprine, furosemide, valproic acid)

Question 17

COX-2 and colon cancer

Answer 17

INCREASES the risk of adenomatous polyps

Question 18

Arteries that run being posterior duodenum

Answer 18

Gastroduodenal

Branches = superior pancreaticoduodenal and right gastroepiploic

Question 19

Malrotation of midgut: GI positioning, s/s

Answer 19

Cecum fixed to duodenum in URQ via Ladd bands.
Whole midgut fixed to SMA

s/s =
volvulus
Duodenal obstruction (bilious vomiting)

Question 20

Acute opioids on the GIT

Answer 20

Contraction of smooth muscle of sphincter of Oddi –> increase biliary pressure –> biliary colic

Question 21

Which has more acute s/s; hep B or hep C?

Answer 21

Hep B - serum-sickness-like: fever, malaise, rash, pruritis, LAD, joint pain

Acute Hep C usually asymptomatic

Question 22

APC gene role:

Answer 22

Intracellular adhesion and inhibition of proliferation

Question 23

Boarders of femoral hernias

Answer 23

Medial = inguinal ligament
Lateral = Femoral vein

Question 24

GIT condition mimicking unstable angina

Answer 24

Diffuse Esophageal Spasms

- chest pain not relieved by rest and intermittent dysphagia

Question 25

Carcinoid cells

Answer 25

Neuroendocrine: APUD/enterochromaffin

Question 26

Drugs to slow down gastric motility

Answer 26

Loperamide and diphenoxylate - mu opioid agonists

Question 27

Ribavirin MOA

Answer 27

interferes with duplication of viral genetic material

Question 28

Causes of granulomatous bile duct destruction and lymphocyte-rich portal tract infiltrate

Answer 28

Primary biliary cirrhosis | Graft vs. host disease

Question 29

Balloon degeneration vs bridging necrosis

Answer 29

Balloon = hepatocyte injury | Bridging necrosis = hepatocyte death

Question 30

Increased estrogens in liver failure. mechanism and s/s

Answer 30

Decreased estrogen metabolism Increase SHBG production (binds T more, increase E:T ratio) Gynecomastia Spider angiomas Testicular atrophy Decreased body hair

Question 31

Ground-Glade hepatocytes =

Answer 31

HepB; full of HBsAg

Question 32

MC watershed areas of the bowel

Answer 32

Splenic flexure | Distal sigmoid colon

Question 33

Bioavailability (F) =

Answer 33

AUC oral / AUC IV

Question 34

NAC mechanism

Answer 34

1) Glutathione substitute to detoxify NAPQI 2) Donates sulfhydryl to enhance non-toxic sulfaton elimination of acetaminophen (normal mechanisms @ low doses = sulfation and glucuronide conjugation)

Question 35

Treatments for different types of nausea:

Answer 35

Visceral (chemo, GI bug, anesthesia) = 5HT3 antagonist Vestibular = antimuscarinic and H1G1 Migraine = dopamine antagonists *all are antagonists*

Question 36

Secretin test

Answer 36

Normally secretin (from duodenum, in response to low pH) causes HCO3- from pancreas and inhibits gastrin release from G-cells In ZE, secretin stimulation INCREASES gastrin levels (ZE = ulcers past duodenal bulb

Question 37

Hepatic steatosis mechanism:

Answer 37

1) inhibition of FA oxidation by increase NADH form alcohol metabolism 2) decrease lipoprotein synthesis and secretion 3) increased peripheral fat catabolism

Question 38

Enzyme that's inhibition leads to cholesterol stones

Answer 38

7a-hydroxylase

Question 39

Abetalipoproteinemia s/s

Answer 39

Malabsorption stuff SI with foamy cytoplasm Acanthocytes Neurological: progressive ataxia and retinitis pigmentosa

Question 40

UC CRC vs. sporatic

Answer 40

- younger - early p53 and late APC - come form flat lesions (not polypoid) - mucinous/signet ring - proximal colon - multifocal - higher grade

Question 41

cause of direct inguinal hernias; covering

Answer 41

Weakness of transversals fascia Covering = only external spermatic fascia

Question 42

Calculating calories

Answer 42

``` protein = 4 carbs = 4 fat = 9 ethanol = 7 ```