A school teacher was posted to a rural school where the classroom windows were not screened. As a result, she got bitten by mosquitoes. What organism was she most probably exposed to as a result of the bites?
C. Brugia malayi
TISSUE NEMATODES FILARIA
Wuchereria bancrofti (mosquito)
Brugia malayi (mosquito)
Brugia timori (mosquito)
Loa loa (deer fly)
Onchocerca volvulus (black fly) river blindness/ larvae in subcutaneous tissue
Dracunculus medinensis (water flea)
TISSUE NEMATODES FILARIA
adults in tissue
eggs not produced
(slide 38-42 Adeb-Helminth)
A community health practitioner observed that many school children in a rural area appeared to be lethargic and pale looking. The children spent a lot of time running around bare-footed and often complained of an intense pruritic and erythematous rash on the feet. Many of them had low-grade fever with abdominal pain and intermittent diarrhea. Blood examination showed evidence of hypochromic, microcytic anemia and many ova were found in the stool specimens.
Which of the following organisms was most probably responsible for the infection?
A. Ancylostoma duodenale
Ancylostoma duodenale (hook)-barefoot-intestine
ENTEROBIUS VERMICULARIS (pinworm) common in US- children most affected
STRONGGYLOIDESSTERCORALIS (threadworm) larvae penetrate skin-adults intestine -larvae in stool
ASCARIS LUMBRICOIDES (roundworm) – most common world wide
What type of cell is the M cell found in the intestinal tract?
B. A specialized epithelial cell responsible for antigen transcytosis
Immune response to GI antigen
antigen in lumen
‐innate immune response‐
(M cell transcytosis)
loading to dendritic cell
processing and presentation
lymphocyte effector cells ‐adaptive immune response
(slide 26 GI defense -Adeb)
Dr Charyk (facilitated by Dr Fitzgerald)
Early symptoms in a case of acute appendicitis usually include:
D. Epigastric or periumbilical pain and nausea
In a case of acute appendicitis, the early symptoms typically include epigastric or periumbilical pain and nausea. This means that the pain and discomfort are felt in the upper abdomen or around the belly button area, accompanied by a feeling of nausea. These symptoms are important to watch out for as they can help in identifying the condition and seeking prompt medical attention. The other symptoms mentioned in the question, such as extreme thirst and hunger, high fever, left lower quadrant abdominal pain, and diarrhea, are not typically associated with acute appendicitis.
Treatment of peptic ulcer disease should include:
The correct answer is antibiotics. Peptic ulcer disease is primarily caused by a bacterial infection called Helicobacter pylori. Antibiotics are necessary to treat this infection and help heal the ulcers. NSAIDs, such as aspirin or ibuprofen, can worsen peptic ulcers and should be avoided. A lactose-free diet may be recommended to reduce symptoms, but it is not a direct treatment for the underlying cause. Alka-Seltzer is an over-the-counter medication that may provide temporary relief from symptoms but does not treat the infection. B12 administration may be beneficial for certain individuals, but it is not a primary treatment for peptic ulcer disease.
As part of an investigation, a patient undergoes esophageal manometery. At one recording site, the pressure before a swallow (at rest) was above atmospheric. Following the initiation of a swallow, the pressure at this site decreased transiently, then increased above that at rest before returning to the at rest pressure. Where was the manometer sensor most likely to have been situated?
A. The upper esophageal sphincter
The manometer sensor was most likely situated at the upper esophageal sphincter because the pressure at this site decreased transiently during a swallow, indicating the opening of the sphincter to allow the passage of food or liquid. The subsequent increase in pressure above the rest indicates the closure of the sphincter after the swallow.
Use of OTC drugs such as ibuprofen is a significant factor in the development of peptic ulcer disease. What is the most likely mechanism by which ibuprofen leads to this condition?
B. Inhibition of cyclooxygenase – thereby increasing gastric acid secretion and decreasing bicarbonate secretion
Ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that inhibits cyclooxygenase, an enzyme responsible for the production of prostaglandins. Prostaglandins play a protective role in the stomach by increasing the production of mucus and bicarbonate, which help to neutralize stomach acid and prevent damage to the stomach lining. When ibuprofen inhibits cyclooxygenase, it reduces the production of prostaglandins, leading to decreased mucus and bicarbonate secretion. This imbalance between acid and protective factors can result in increased gastric acid secretion and decreased bicarbonate secretion, making the stomach more susceptible to developing peptic ulcers.
In a laboratory experiment the rate of galactose absorption is being measured across a sheet of jejunum. What will be the most likely effect of the following maneuvers on the rate of absorption of this monosaccharide?
B. Addition of a sodium-pump (Na/K-ATPase) inhibitor to the mucosal solution will decrease galactose uptake
Adding a sodium-pump inhibitor to the mucosal solution will decrease galactose uptake. The sodium-potassium pump is responsible for maintaining the concentration gradient of sodium and potassium ions across the cell membrane. By inhibiting this pump, the concentration of sodium ions inside the cell will increase, leading to a decrease in the electrochemical gradient that drives the uptake of galactose. As a result, the rate of galactose absorption will be reduced.
A rise in the pH of the duodenal contents will most likely have which of the following effects on pancreatic duct cell function?
D. Decreased apical bicarbonate-chloride exchange due to reduced release of secretin
A rise in the pH of the duodenal contents will lead to a decrease in the release of secretin, a hormone that stimulates the release of bicarbonate ions from pancreatic duct cells. This decrease in secretin release will result in a decreased apical bicarbonate-chloride exchange, as the reduced secretin levels will inhibit the transport of bicarbonate ions from the cell into the duodenum. Therefore, the correct answer is decreased apical bicarbonate-chloride exchange due to reduced release of secretin.
Entry of fats to the duodenum is associated with which of the following DIRECT effects on smooth muscle cells of the gall bladder and sphincter of Oddi?
E. Contraction of the gall bladder mediated by acetylcholine and relaxation of the sphincter of Oddi mediated by nitric oxide
When fats enter the duodenum, the gall bladder contracts to release bile into the small intestine to aid in fat digestion. This contraction is mediated by acetylcholine. On the other hand, the sphincter of Oddi, which controls the flow of bile from the common bile duct into the small intestine, relaxes to allow the bile to pass through. This relaxation is mediated by nitric oxide. Therefore, the correct answer is "Contraction of the gall bladder mediated by acetylcholine and relaxation of the sphincter of Oddi mediated by nitric oxide."
A 24-year-old medical student with a known history of long-standing Crohn’s Disease comes to see his Gastroenterologist, reporting a 3 month history of increasing numbness in his fingertips and “pins and needles” in his feet (Peripheral Neuropathy). Based on this patient’s history and chief symptoms, what is the most likely vitamin or mineral deficiency that would explain these symptoms?
D. Vitamin B12
The most likely vitamin or mineral deficiency that would explain the patient's symptoms of numbness in fingertips and "pins and needles" in feet is Vitamin B12 deficiency. Vitamin B12 deficiency can lead to peripheral neuropathy, which is characterized by nerve damage in the peripheral nervous system. This deficiency is commonly seen in patients with Crohn's Disease, as the disease can cause malabsorption of nutrients including Vitamin B12.
The muscles of the anterior abdominal wall have a distinct anatomic arrangement. One named muscle of the anterior abdominal wall arises along the inguinal ligament and iliac crest, whose fibers travel upward and medially to insert in the midline at the linea alba and superiorly on the borders of the lower three ribs. What is the name of the muscle described?
E. Internal oblique
The muscle described in the question is the Internal oblique. It arises along the inguinal ligament and iliac crest and its fibers travel upward and medially to insert in the midline at the linea alba and superiorly on the borders of the lower three ribs.
A 13-year-old boy is brought into the emergency department with blunt trauma to the left side of the chest during an attack by members of a rival street gang. X-ray shows fracture of the 9th and 10th ribs. Which of the following organs would most likely be damaged?
Blunt trauma to the left side of the chest can cause damage to the spleen, as it is located in the left upper quadrant of the abdomen, just beneath the left rib cage. Fracture of the 9th and 10th ribs suggests a significant force of impact, which can result in injury to the spleen due to its proximity to the site of trauma. The other organs listed are not typically located in the left upper quadrant and are therefore less likely to be damaged in this scenario.
A 42-year-old man has been a chronic alcoholic for over 20 years. He presents to the emergency room with sudden onset of massive ascites. He is diagnosed with portal hypertension secondary to cirrhosis of liver. He underwent surgery. Which of the following surgical connections is involved in shunting portal blood around the liver?
C. Splenic vein to the left renal vein
The correct answer is splenic vein to the left renal vein. In portal hypertension, there is increased pressure in the portal vein due to liver cirrhosis. This increased pressure can lead to the development of collateral vessels to bypass the liver. One such collateral is the left renal vein, which can receive blood from the splenic vein. This shunting of portal blood from the splenic vein to the left renal vein helps to alleviate the pressure in the portal system and reduce the formation of ascites.
A large tumor mass impinges on the splenic artery and its branches. Branches of which of the following arteries would most likely be affected by the pressure on the splenic artery?
E. Short gastric
A large tumor mass impinging on the splenic artery would most likely affect the short gastric arteries. The short gastric arteries are branches of the splenic artery that supply blood to the fundus and upper part of the greater curvature of the stomach. Since the tumor is putting pressure on the splenic artery, it is likely to disrupt blood flow to its branches, including the short gastric arteries. This can lead to ischemia and potential damage to the affected areas of the stomach.
A transition from simple columnar epithelium with simple tubular glands (predominant cell type is goblet) to non-keratinized stratified squamous epithelium is revealed in a histological slide. The specimen is taken from one location in the GI tract. Based on the observation, which part of GI tube is under inspection?
C. Pectinate line
The transition from simple columnar epithelium to non-keratinized stratified squamous epithelium suggests a change in the lining of the GI tract. The pectinate line is a distinct anatomical boundary in the anal canal where the epithelium changes from simple columnar to non-keratinized stratified squamous epithelium. Therefore, based on the observation, the part of the GI tract under inspection is the pectinate line.
Periodontal ligaments are derived from
D. Neural crest
except for enamel, the tooth and its associated structures (odontoblasts,dentin, cementoblast, cementum, Periodontal ligaments, c.t. of the gingiva, alveolus) are derived from Neural Crest Cells. (46minute mark of mediasite on GI&oral cavity- Yin)
An ideal hepatocyte stacked in a hepatic cord is being viewed schematically. With four sides of this hepatocyte abutting other hepatocytes, the remaining two sides of this hepatocyte are left facing_____ directly.
C. Space of Disse
Are specialized capillaries that carry blood through the liver parenchyma.
Associated with three types of cells:
Endothelial cells (F.G.B.)
Kupffer cells: APC
Fat-storing cells (Ito cells): stellate cells in space of Disse.
Small enlargement in the extracellular space between two adjacent hepatocyte. Sealed by zonula occludens.
They form a continuous, polygonal branching system with the lobule.
Join the bile ducts in portal triad via short squamous canals of Hering (bile ductules).
Two bile ducts exit the liver and merge to form hepatic duct
(Slide 19,20 Hep-biliar-Yin)
The appendix is supplied by which of the following structures?
C. Superior mesenteric artery
The correct answer is the Superior mesenteric artery. The appendix is supplied by the superior mesenteric artery, which is a major branch of the abdominal aorta. It provides blood supply to the midgut, including the appendix, small intestine, and part of the large intestine. The celiac trunk supplies blood to the foregut, the inferior mesenteric artery supplies blood to the hindgut, the internal iliac artery supplies blood to the pelvis, and the portal vein carries blood from the gastrointestinal tract to the liver.
The cells labeled with the asterisks in the accompanying EM function in
E. Immune defense
I think it is a Lymphocyte, slide 3 of Yin's EM ppt. is the closest I can find. if it is not a Lymphocyte, then
Im pretty sure this is an M-cell, but it is not from her slides. she has 4 consecutive slide on M-cells (39-42 Stom&intest-Yin) I would be familial with those for the exam.
Dr Mallik (facilitated by Dr Fitzgerald)
A 45-year-old male complains of difficulty in swallowing both liquids and solids for past 10 years, which has worsened gradually over the time. He also suffers from nocturnal cough, which disturbs his sleep as well as regurgitation of undigested food eaten several hours earlier. Physical examination does not reveal much. Barium studies are performed which shows dilated lower esophagus, loss of esophageal peristalsis, and smooth tapering of the distal esophagus. You divided the esophageal sphincter for treatment and after 3 months the patient presents with pain in the chest and heart burn. What is the complication of the treatment?
C. Reflux esophagitis
After dividing the esophageal sphincter for treatment, the patient develops pain in the chest and heartburn. This suggests that the complication of the treatment is reflux esophagitis. Reflux esophagitis occurs when stomach acid flows back into the esophagus, causing inflammation and irritation of the esophageal lining. The symptoms of difficulty in swallowing and regurgitation of undigested food may have improved after the treatment, but the division of the sphincter has disrupted the normal barrier that prevents acid reflux, leading to the development of reflux esophagitis.
A 25-year- old woman was admitted to the hospital with complaints of pain over the periumbilical region. She was febrile (39.5 C), nauseated and had non-violent vomiting. Physical examination revealed a positive psoas sign and deep tenderness at the McBurney’s point. She was diagnosed with acute appendicitis. Trace the path of pain sensation elicited by an inflamed appendix to the central nervous system (CNS).
A. Appendix → superior mesenteric plexus → lesser splanchnic nerve → white ramus communicans → anterior primary ramus → dorsal root ganglion → T10 spinal level
The correct answer explains the pathway of pain sensation from an inflamed appendix to the central nervous system. According to the answer, the pain sensation starts from the appendix and travels through the superior mesenteric plexus. From there, it continues through the lesser splanchnic nerve and enters the white ramus communicans. The pain signal then passes through the anterior primary ramus and reaches the dorsal root ganglion. Finally, it ascends to the T10 spinal level, where it is transmitted to the central nervous system.
A 60-year old man is admitted in the emergency department after he was involved in an automobile accident. He suffered blunt trauma to his abdomen and complains of generalized lower abdominal pain. There is no evidence of hematochezia or bowel obstruction. The surgeon decides to perform an exploratory laparoscopy of the infracolic compartment. On examination, the surgeon finds out that the patient has a Meckel’s diverticulum. Which of the following statement is correct about this diverticulum?
D. It may contain gastric mucosa
Often contain at least 2 types of mucosa: (Ileal, Acid producing gastric tissue, Pancreatic tissue,
Jejunal or Colonic)
Most common congenital anomaly of the bowel.
Vestige of embryonic yolk stalk as a result of failure of involution of vitelline (omphalomesenteric) duct
Syndrome of 2’s
~ 2 inches long
~ 2% of population
2 types of mucosa
~ 2 feet proximal to ileocecal
2 major complications (bleeding & obstruction)
Can become inflamed and produce pain and symptoms associated with appendicitis
(Slide 14 infr colic- Kirera)
The DRI of Vitamin A for an 18a old ♂ is: EAR 625 ug/d, RDA 900 ug/d and UL 2800 ug/d. A patient of that group taking on average 950 ag/d will suffer from symptoms of
D. Deﬁciency with a probability of about 2%
Estimated Average Requirement (EAR) intake meets requirements of half the healthy
individuals in a group (sex, age).
Recommended Dietary Allowance (RDA) best judgement of a group of experts on the daily
amounts that are sufficient and safe for a healthy individual. EAR
plus 2 standard deviations.
tolerable Upper intake Level (UL) highest level of daily intake that is likely to pose no risks of
adverse heath effects to almost all individuals of a group.
Dietary Reference Intake EAR, RDA and UL
Adequate Intake intake of a healthy reference population where data are insufficient to
determine EAR and hence RDA.
US Recommended Daily Allowance highest RDA (based on 1968 recommendations) in
any gender and age group above 4 years
A 4-month-old male was admitted to the hospital in a coma. Blood analysis taken on admission revealed a blood glucose of 15 mg/dL (normal 60-100 mg/dL). He had no acidosis or ketosis. A 24 hour fast produced a dramatic drop in blood glucose and a rise in serum triglycerides. Liver and muscle biopsy showed accumulation of fat. This infant most likely has
E. Carnitine deficiency
Diseases of carnitine shuttle
Carnitine palmitoyltransferase II deficiency: Three forms:
I Adult: OMIM #255110. Muscle problems (myalgia, rhabdomyolysis, myoglobinuria) during attacks, otherwise normal. Attacks induced by exercise, fasting, high-fat diet, infection. Highly variable age of onset, | more strongly affected.
I Infantile: OMIM #600649. Age of onset usually 1a, but sometimes later. Hypoketotic hypoglycemia, loss of consciousness and seizures, hepato- and cardiomegaly.
I Neonate: Onset hours to days after birth, rapidly fatal from cardiac, respiratory or liver failure.
Neuronal migration defects, kidney dysorganization.
Treatment: low lipid intake, medium chain fa, carnitine, avoid strenuous exercise. Bezafibrate may induce enzyme expression.
I Systemic primary carnitine deficiency: SLC22A5 gene on chromosome 5q31.1, renal re-uptake transporter OCTN2 (Na+-cotransport). Frequency Faroe Islands 1 in every 500, otherwise 1 in several 10000. OMIM #212140. Hypoketotic hypoglycemia, Reye-syndrom like episodes, lethargy, somnolence, hepato- and cardiomegaly.
Treatment: oral supplementation of carnitine
I Carnitine palmitoyltransferase I deficiency: hypoketotic hypoglycemia, Reye-syndrom like episodes,
hepatomegaly, muscle weakness. OMIM #255120.
Treatment: prevent hypoglycemia with short- and medium-chain fa in diet
I Carnitine-acylcarnitine translocase deficiency: Presents within hours of birth with seizures, bradycardia, breathing problems, hypoketotic hypoglycemia, hyperammonemia, hepatomegaly, cardiomyopathy, muscle weakness, sudden infant death. OMIM #212138.
Treatment: low lipid intake, medium chain fa, carnitine, avoid strenuous exercise.
(slide 21 22 Buxb-FA met)
A 55-year-old man has significantly reduced reabsorption of bile salts resulting from the action of bile salt-binding resins. This is expected to lead to a significant increase in which of the following substances?
C. 7α-hydroxylase activity
7a-Hydroxylase: Controlled by negative feed back of bile acids & Requires thyroid hormones and vitamin C for activation
Dietary Cholesterol Plays a predominant role through HMG-CoA reductase and 7a-hydroxylase. The rate of synthesis of cholesterol is regulated by feedback inhibition of HMG-CoA reductase by excess cholesterol. If large amounts of dietary cholesterol are entering the liver then the rate of synthesis is inhibited. Excess amount of cholesterol can then be excreted as bile acids which will result in the activation of 7a-hydroxylase.
It is fortunate for some individuals on high cholesterol diets that intestinal absorption of cholesterol is not very efficient
(slide 35,38 Memb lipid-Laville)