HST120 Student Final Questions Sang Kim What is the name of the associated glycogen storage disease? a) deficiency of amylo-1-6-glucosidase. A polysaccharide with short outer chanins accumulates in all tissues. Answer: limit dextronosis (type III) b) deficiency of glucose-6 phosphate. Answer: von Gierke Disease (type Ia) c) deficiency of debranching enzyme. A polysaccharide with long outer chain accumulates. Answer: amylopectinosis (type IV).
Minhaj Mark the following as True or False of Cystic Fibrosis: T - Autosomal Recessive T - Most common mutation is (delta)508 F - Increased viscosity of mucous secretions due to defective cAMP-activated Na channels (really is Cl channels) T - can cause billiary cirrhosis
Ellen Yeh Identify the labeled structures in the following diagram of a hepatic lobule. Indicate regions of perfusion, zone 1 (highest oxygen tension) to zone 3 (lowest). [Insert labeled diagram of hepatic lobule] [Ans: Structures to be labeled- central vein, portal triad containing hepatic artery, bile duct, and portal vein, and sinusoids. Zone 1 periportal, zone 2 intermediate, and zone 3 perivenular] Indicate which zone is most susceptible to damage by the following agents/processes: 1) Drugs Zone 1- xenobiotics from GI absorption in portal vein 2) Virus Zone 1- virus delivered from systemic circulation 3) Systemic hypoxia Zone 3- farthest from arterial perfusion 4) Biliary tract disease Zone 1- stasis and inflammation from bile duct disease 5) Right-sided heart failure Zone 3- central vein congestion
David Cochran The 3 primary pathways of alcohol degradation are ______________, _____________, and _____________________. The increased NADH/NAD+ ratio has 2 effects on fatty acid metabolism: __________________________ and _________________________. The net clinical result of this is ___________________. Alcohol exacerbates acetaminophen toxicity by increasing ___________________ activity and depleting stores of __________________. Answers: alcohol dehydrogenase, microsomal ethanol oxidizing system, and catalase increased fatty acid synthesis and decreased fatty acid oxidation steatosis or hyperlipidemia cytochrome P450 glutathione
Susan Zhao A 43-year-old man presents with increased skin pigmentation, cirrhosis, malabsorption, and diabetes mellitus. The mechanism most likely responsible for this constellation of findings is: A. B. C. D. E. 1-antitrypsin deficiency a defect in the excretion of copper in bile multisystem organ damage from alcohol excessive reabsorption of iron from the small bowel multisystem organ damage from amyloid
Answer: D The patient most likely has hemochromatosis, which is an autosomal recessive disease with a HLA A3 inheritance pattern in 70% of cases. It is characterized by excessive absorption of iron from the small bowel. The deposition of iron is predominantly parenchymal where iron is instrumental in the generation of injurious hydroxyl free radicals. Clinical findings include: Cirrhosis Hepatocellular carcinoma Pancreatic exocrine insufficiency with malabsorption Diabetes mellitus (late finding) Restrictive cardiomyopathy, and heart failure Pituitary insufficiency
Increased skin pigmentation, due to an increase in melanin and hemosiderin deposition in the dermis. Hemosiderosis is an acquired iron overload. Iron primarily deposits in macrophages in the liver, spleen, and bone marrow. It is usually secondary to anemia, alcoholic liver disease and those have had over 100 blood transfusions.
Other choices: 1-antitrypsin deficiency is the most common cause of childhood cirrhosis, but doesn’t produce the constellation of findings noted in this patient. A defect in the excretion of copper in bile is characteristic of Wilson disease, but this disease primarily produces central nervous system disease and cirrhosis of the liver Multisystem organ damage from alcohol or amyloid would not produce the constellation of findings noted in this patient.
Elizabeth Stover Match the disease and associated pathological feature: Mallory bodies Anti mitochondiral Ab's Fat necrosis Signet ring cells Fissuring ulcers "Strawberry" mucosa OR Q. Name the two most common causes of acute pancreatitis: A. Alcoholism, biliary tract disease (cholelithiasis) Alcoholic heptatits Primary biliary cirrhosis Pancreatitis Diffuse gastric carcinoma Crohn's disease Cholesterol gallstones
Rachel Forbes Q: Why is excess tylenol dangerous for hangovers, especially in cases of chronic alcohol consumption? A: Acetaminophen can be broken down in the liver by cytochrome P450 into a toxic electrophilic metabolite (NAPQI) that can cause hepatic injury. In order to prevent this, detoxification of the metabolite usually occurs via GSH-transferase. Alcohol causes problems by (1) reducing the amount of glutathione stores available for the GSH-
transferase. (2) In cases of chronic use or abuse of alcohol, the liver may increase cytochrome p450 resulting in faster breakdown of tylenol into toxic metabolite, without increased breakdown of the metabolite itself. Both factors contribute to the metabolite being in the liver for extended time where it can cause hepatic injury. Treatment for tylenol overdose: 1. administration of N-acetly cystine may help restore glutathione levels, helping to expedite clearing metabolite 2. Hyperbaric oxygen may inhibit cytochrome P450's ability to produce further the metabolite via covalent linkage of CCL3 to cyto P450
Christina Wilbert Patient A is a 78 yr. old woman is diagnosed with a stromal tumor of the jejunum. She is treated with a 30 cm resection of the affected small bowel. Patient B is a 27 yr. old female who presents with right upper quadrant pain, diarrhea, weight loss and rectal bleeding. Endoscopy with biopsy reveals several ulcerating lesions in the terminal ileum consistent with Crohn’s disease. She did not improve with medical therapy and opted for a surgical resection of the affected bowel. Which patient will experience the greatest malabsorbtion and steatorrhea? Patient B.
Match the following statements about hepatitis viral infections with the appropriate agent: HAV, HBV, HCV, HDV, or HEV. a. Transmitted parenterally, sexually, and vertically. Acute infections progress to chronic infections about 10% of the time. HBV. b. Although infection symptoms are milder than in (a), the incidence of cirrhosis and hepatocellular carcinoma is high due to the 80% chronicity rate. HCV. c. Spread via the fecal-oral route and results in acute hepatitis or asymptomatic infection. A safe and effective vaccine has been developed against this virus. HAV. d. Spread via fecal-oral route and does not result in chronic infection, although acute infections are generally more severe than those of (c). HEV. e. This is not a true virus and thus does not directly cause infection, but rather exacerbates infection from (a). HDV.
Eric Chang Choose all correct answers. Obstruction of bile duct would result in: A. increased content of lipids in feces. B. increased excretion of dietary cholesterol in feces. C. increased conjugated bile pigments in serum. D. decreased excretion of bilirubin glucuronides in urine. Answer: A, B, C Explanation: Obstruction of the bile duct means bile cannot enter the duodenum. Bile micelles are important in the digestion and absorption of lipid and their absence causes increased lipids in the stool. Also, conjugated (water-soluble) bile pigments will appear in the plasma and because they are water-soluble they will be filtered by the kidney and appear in the urine.
Zuzana Tothova Please match the following enzymes with their site of action and digestive action: salivary amylase ___ ___ pancreatic amylase ___ ___ dissacharidases (sucrase, lactase, trehalase) ___ ___ maltase, -dextrinase ___ ___ Site of action: 1 brush border 2 mouth 3 duodenum Digestive Action: A. degrade respective dissachardises to monosaccharides B. hydrolyzes - 1,4 glycosidic bonds in starch, yielding maltose, maltotriose, and alphalimit dextrins C. digest oligosaccharides from complex carbohydrates (maltose, -limit dextrins) to glucose
Answer: Salivary amylase: 2, B Pancreatic amylase: 3, B Dissaccharidases: 1, A Maltase, -dextrinase: 1, C
Larissa Lee Individuals with impaired hepatic secretion of (blank) are at greater risk of developing emphysema and hepatic cirrhosis. Answer: Alpha 1 Antitrypsin
Ning Lin Question: During enterohepatic circulation, how is bile salt reabsorbed in the gut and recaptured in the liver? Is it a passive or active process? What transporters play important roles in these processes? Where are they located? Answer: Bile salts passively diffuse into blood stream from duodenal, jejunal, and colonic sites. But the majority of bile salt reabsorption happens in the ileum where a bile salt transporter (coupled with Na+) is present on the apical membranes of absorptive cells. The reabsorbed bile salts are transported back to liver via portal system, and are extracted by NTCP, a Na+-BS symporter capturing common bile salts from blood. Recaptured bile salts are quickly secreted into bile again to complete an enterohepatic circulation.
Andrew Levin T/F Questions regarding Portal Circulation and Portal Hypertension T – Portal venous blood goes through two capillary beds. F – The portal venous system contains valves, which eliminate the possibility of bidirectional flow. T – Mechanisms of portal hypertension include increased flow and increased resistance. T – Esphageal varices and perirectal hemorrhoidal channels can occur as a result of portal hypertension.
Anthony Philippakis Q: Describe the location of the H+/K+ ATPase pumps of the parietal cell during the stimulated and resting states.
A: During the non-stimulated resting state, the pumps are localized primarily in vesicles in the cytoplasm of the parietal cell. During the stimulated state, the pumps move to the apical membrane.
Eric Chang All of the following conditions are correctly matched with the appropriate phrase EXCEPT (A) achalasia – acid gastric reflux (B) Mallory-weiss syndrome – esophageal mucosal tears and hemorrhage due to retching (C) esophageal varices – portal hypertension (D) Barrett’s esophagus – lesion predisposing to maliganancy Answer: (A)
Richard Lin Trisomy 21 is found in what type of congenital defects of the GI tract? (A) Meckel's diverticulum (B) Dudeno atresia (C) Pyloric stenosis (D) Esophageal atresia and tracheoesphageal fistula Answer: (B)
Annemarie Stroustup True or False? Chronic cholecystitis most commonly results from untreated symptomatic acute cholecystitis. (false) In patients with gallstones, single gallstones are more common than multiple gallstones. (false)
Megan Coffee Hepatocellular Carcinoma is associated with ----- from Aspergillus, ----- infection in high incidence areas, which is higher in [men/women] and occurs particularly in the continents of ---- and -----. aflatoxin B, HBV, men, Africa, (Southeast) Asia
Grant Garrigues These insoluble nonswelling amphiphiles make up the majority of dietary fat (95%): (A) Long-chain Triglycerides (B) Cholesterol (C) Phospholipids (D) Steryl esters Answer: (A) Long-chain Triglycerides
Jocelyn Songer Gilbert's syndrome is relatively commom, benign disorder due to a _________ in glucuronyltransferase activity. This results in a mild _________ hyperbilirubinemia. Answers: decrease unconjugated
Neil Hattangadi True/False questions on bile; all false answers must be briefly explained: 1) Chylomicrons are formed in the intestinal lumen. (F -- chylomicrons are formed within the intestinal epithelial cells; micelles are formed in the lumen) 2) Secondary bile salts are synthesized from cholesterol in the hepatocyte. (F -- primarily bile acids are synthesized from cholesterol in hepatocytes; secondary bile salts are produced by anaerobic colonic flora)
3) Bile salts are the same as bile acids. (F -- Bile salts are made from the conjugation of glycine or taurine to bile acids to make them more water soluble and better emulsifiers) 4) Bile is absorbed in the ileum mainly by the ASBT transporter. (T) 5) Synthesis of steroid hormones is the primary mechanism of cholesterol excretion. (F -loss of bile in feces is the primary excretion mechanism) 6) The gallbladder increases the alkalinity of bile. (F -- a H+/Na+ exchanger is used to acidify bile in the gallbladder)
Russ Huber Which symptoms and factors are commonly associated with acute and/or chronic pancreatitis? Symptom or factor Chronic Pancreatitis Acute Pancreatitis Abdominal Pain Increased Serum Amylase Gallstones Pancreatic Insufficiency Alcohol Abuse Diabetes x x x x x
x x x