GI SAQ

Gastrointestinal System Anatomy 2005 Q1 List five major characteristics of colon which distinguish it from small intestine. (10 marks)

2008 Q12 A 55-year-old female underwent resection of the large bowel due to colon cancer. The surgeon has to distinguish the small intestine from the large intestine during the operation. List five main external features that distinguish between small and large intestines. (10 marks)

2009 Q12 / 201 2 011 1 Q12 A 70-year-old male was diagnosed with irreducible indirect inguinal hernia. Surgery was performed to repair the inguinal canal. (2009)  A 65-year-old male was diagnosed with irreducible large indirect inguinal hernia. Hernial repair was carried out. (2011)  (a) List four important anatomical structures derived from the abdominal wall that forms the inguinal canal. (8 marks) Stru cture of i nguin al  canal 

Str uctur e der der ived ived fr om the abdominal abdominal wall 

Anterior wall Posterior wall Roof orsuperior wall Floor or inferior wall

(b) List one function of the inguinal canal. (2 marks)

2008 Q1 (a) (a) Lymphatic spread is a common rout of colon cancer. What are the lymph nodes immediately draining from the colon? (4 marks)

Embryology 2004 Q13 The shape and orientation of the stomach are produced by a combination of  differential growth of the stomach wall and rotation of the stomach. (a) Which side of the stomach primordium undergoes the greatest expansion? (2 marks) (b) What is the direction of rotation of the stomach around a craniocaudal axis? (2 marks) (c) What is the direction of rotation of the stomach around a dorsoventral axis? (2 marks) (d) That is the anatomical relationship of the stomach and the vagus nerve after rotation? (4 marks)

2010 Q10 During development, the pancreas is formed from two buds. (a) What is the embryonic origin (germ layer) of the pancreatic buds? (2 marks) (b) Describe the developmental process by which the two pancreatic buds fuse into a single structure, the main pancreas and uncinate process. (5 marks) (c) Describe the development of the pancreatic duct system. (3 marks)

Physiology 2004 Q17 The secretion of exocrine glands in the gastrointestinal tract is controlled by various physiological mechanisms. These secretions are increased during a meal. (a) Which two systems control pancreatic exocrine secretions? (2 marks) (b) List the functions of pancreatic exocrine secretions. (2 marks) (c) What reflex stimulates pancreatic exocrine secretions during the gastric phase of a meal? What causes this reflex? (1 mark) (d) List the reflex(es) that stimulate(s) pancreatic exocrine secretions during the intestinal phase of a meal. What causes this/these reflex(es)? (5 marks)

2005 Q15 The secretion of gastric juice is controlled by various physiological mechanisms, and the secretion is increased during a meal. (a) List three components of gastric secretion and their function. (6 marks) Component of gastric secretion

Function

(b) List the two phases of gastric secretion which are stimulatory (2 marks) and list two stimulants of acid secretion. (2 marks)

2009 Q15 The stomach mucosa secretes various substances which carry out different functions. (a) Name the stomach cell types which secrete the following substances: (i) Pepsinogen (1 mark) (ii) Hydrochloric acid (1 mark) (iii) Instrinsic factor (1 mark) (iv) Gastrin (1 mark) (v) Histamine (1 mark) (vi) Bicarbonate (1 mark) (vii) Mucus (1 mark) (b) List three functions of hydrochloric acid. (3 marks)

2011 Q15 The exocrine pancreas secrete bicarbonate and enzymes. (a) Name three proenzymes secreted by the pancreas. (3 marks) How are they activated? (1 mark) (b) Which pancreatic anzyme is responsible for the digestion of carbohydrate? Describe its function. (2 marks) (c) Which is the most important phase in the control of pancreatic enzyme secretion? (1 mark) How is the secretion of pancreatic enzymes regulated in this phase? (3 marks)

2010 Q13 Vomiting is a reflex response. (a) Give three examples of emetic stimuli. (3 marks) (b) Describe the vomiting reflex (6 marks) (c) Name two complications associated with severe vomiting. (1 mark)

Biochemistry 2004 Q14 Degradation of haemoglobin in the spleen results in liberation of the haem moiety from globin and conversion to a form which then is released into the blood and transported to the liver. (a) What os the product of haem catabolism in the spleen? (1 mark) (b) Name the protein that binds the product in (a) as it is transported in the bloodstream. (1 mark) (c) In the hepatocytes, how is the product converted into a water-soluble form for excretion via the bile? (4 marks) (d) If therapeutic dosage of a non-steroidal anti-inflammatory drug (e.g. ibuprofen) is administered to a patient, how would this affect the transport of the product in (a) in the blood? (4 marks)

2005 Q8 Cholesterol biosynthesis is regulated by low density lipoprotein (LDL)-bound cholesterol and specific LDL receptors that project from the surface of cells. (a) How is endogenous cholesterol taken up by the cells in tissues? (4 marks) (b) How does uptake of endogenous cholesterol regulate cholesterol synthesis in the body? (4 marks) (c) Patients with familial hypercholesterolemia fail to regulate cholesterol biosynthesis by this mechanism. Why? (2 marks)

2006 Q10 (a) List three mechanisms by which cholesterol synthesis may be regulated. (6 marks) (b) Which one of the mechanisms in (a) is commonly used as drug target to control plasma cholesterol level? (1 mark) (c) What could be the consequences in cholesterol metabolism under long term usage of drugs that target for the mechanism in (b)? (3 marks)

2007 Q12 ’

The hereditary unconjugated hyperbilirubinaemia in Gilbert s syndrome patients is caused by defective bilirubin UDP-glucuronyltranferase. (a) What is the role of bilirubin UDP-glucuronyltransferase in bilirubin clearance in a normal individual? (1 mark) Explain. (1 mark) (b) Do you expect to find any bilirubin in urine from such patients? Explain briefly. (3 marks) (c) What would be the diagnostic test for the patient if he also suffers from haemolytic cholestasis? (1 mark) Explain. (4 marks)

2009 Q13 After feasting on a wedding banquet in Yuen Long, Ying complained of nausea and vomiting. She had low grade fever and noted increasing abdominal pain. Laboratory test indicated serum levels of  alanine transaminases (ALT) aspartate transaminases (AST) amylase and lipase total bilirubin

294 units/L (reference: 5 - 30) 268 units/L (reference: 10 - 30) within reference range 9.6 mg/dL (reference: 0.2 - 1.0)

(a) Consider the given serum enzyme levels. (i) Which organ is likely afflicted with inflammation? Explain. (2 marks) (ii) Which organ is likely not afflicted with inflammation? Explain. (1 mark) (b) (i)

Name the two forms of bilirubin included in the measurement of total bilirubin in blood. (2 marks)

(ii) How are these forms derived from haem degradation? (3 marks) (iii) Name the tissues involved in the conversion. (2 marks)

2011 Q13 A baby girl appeared normal at birth but developed hyperammonaemia after 24 hours. At 56 hours, she developed focal seizure activity. Blood plasma analyses: citrulline, 200 mM (normal 10 - 20 mM); arginine 40 mM (normal 52 - 72); ammonia, 1,100 mM (normal 5 -35 mM); blood urea nitrogen, 1 mg/dL (normal 4-15 mg/dL). (a) Which of the following urea cycle enzymes may be deficient in this case: Carbamoyl phosphate synthetase I; ornithine transcarbamoylase; argininosuccinate synthetase; argininosuccinate lyase; arginase? (1 mark) Please explain. (2 marks) (b) Name one amino acid that may be elevated in the blood plasma in this case. (1 mark) Write the enzymatic reactions that lead to the elevation. (3 marks) (c) Despite the low production of urea, amino nitrogen can be excreted via urea cycle intermediates that build up as a result of the deficiency. Which amino acid supplement in the diet can be recommended to enhance entry of the amino nitrogen into the urea cycle? (1 mark) Explain your answer using an equation. (2 marks)

Pathology and Microbiology 2004 Q16 Oesophageal cancer is a cancer with a peculiar incidence pattern worldwide. (a) Name two countries/cities which have a high incidence of this cancer. (2 marks) (b) What is the most frequent histological subtype of this cancer locally? (2 marks) (c) What is the most important factor leading to this cancer? (2 marks) (d) What is the most common site in the oesophagus for this cancer? (2 marks) (e) What is the type of spread of this cancer? (2 marks)

2005 Q12 (a) List two viruses that cause faeco-orally transmitted hepatitis. (2 marks) (b) In Hong Kong, what is the source of infection for these viruses? (2 marks) (c) List three preventive measures against infection by these viruses. (6 marks)

2006 Q14 / 2008 Q15 Viral hepatitis is a common disease in Hong Kong and in some parts of the world. (a) Which hepatitic viruses are transmitted by oral-fecal route? Name two. (2 marks) (b) Which hepatitic viruses can give rise to chronic liver disease? Name two. (2 marks) (c) Which hepatitic viruses cause infection by parental transmittion? Name two. (2 marks) (d) Apart from Hong Kong, which parts of the wourld also have a high prevalenve of HBV infection? Name two. (2 marks) (e) The incidence of which viral hepatitis is higher in Japan than in Southeast Asia and Hong Kong. (2 marks)

2006 Q15 (a) (a) Briefly describe the aetiology of gastroesophageal reflux disease. (2 marks) 2005 Q14 / 2010 Q11 / 2011 Q14 Gastric cancer is a cancer occurring worldwide and prevalent in Hong Kong. (a) What is the most frequent histological subtype of this cancer in Hong Kong? (2 marks) (b) Name two of the most important factors leading to this cancer. (2 marks) (c) What is the most common site in the stomach for this cancer? (2 marks) (d) What is the commonest type of spread of this cancer? (2 marks) (e) There is a peculiar form of spread of this cancer. What is it? (2 marks)

2007 Q1 What are the possible routes of metastatic spread of cancer cells originated from colon? (10 marks)

2007 Q14 Hepatocellular carcinoma is a prevalent cancer in Southeast Asia and Hong Kong. (a) Name three aetiological factors of this cancer. (3 marks) (b) What is the tumour marker of this cancer? (2 marks) (c) What is the condition of the liver which is frequently associated with this cancer? (2 marks) (d) Name two differences in the gross appearance and one difference in the mode of spread between hepatocellular carcinoma and cholangiocarcinoma. (3 marks)

2008 Q1 (a) Lymphatic spread is a common rout of colon cancer. What are the lymph nodes immediately draining from the colon? (4 marks) (b) In addition to spreading through lymphatics, list three other routes of  spread of colon cancer in the abdomen. (6 marks)

2008 Q13 A 2-month-old infant was brought to the clinic by his mother. He had presented with watery diarrhoea and flatulence 5 days earlier and was diagnosed with viral gastroenteritis. With continued breast-feeding, diarrhoea and flatulence remained observable. Before the infection, the mother s milk was well tolerated, with no noticeable diarrhoea or flatulence. ’

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(a) Which component of the mother s milk becomes poorly tolerated with the infection? (1 mark) (b) How would a viral infection affect digestion of this milk component? (4 marks) (c) What is the cause of flatulence? (3 marks) (d) Given tolerance of his mother s milk before the infection, what would you recommend for oral rehydration of the infant? Explain. (2 marks) ’

Pharmacology 2006 Q3 Name (2 marks) and describe (6 marks) the two general mechanisms by which drugs may interact to produce an alteration in pharmacological response. Give an example to illustrate such mechanism. (2 marks)

2006 Q15 (b) (a) Briefly describe the aetiology of gastroesophageal reflux disease. (2 marks) (b) Describe two pharmacological means by which this can be controlled, give give one example of each. (8 marks)

2008 Q3 Drugs may interact with each other to produce an alteration in pharmacological effect. Give a definition and one example of each of the following types of drug interaction. (a) (b) (c) (d)

additive effects (2.5 marks); antagonistic effects (2.5 marks); potentiative effects (2.5 marks); synergistic effects (2.5 marks).

2009 Q1 Outline the four pharmacokinetic (ADME) mechanisms by which drugs may interact to produce an alteration in pharmacological response. (6 marks) Give one drug-drug interaction example to illustrate each mechanism. (4 marks)

2010 Q12 What are the clinical uses of metoclopramide? (4 marks) Describe its mechanisms of action. (4 marks) Apart from headache and dizziness, name one adverse effect of metoclopramide. (2 marks)