Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 1 (PCS & Cases 1-6) > Case 3 > Flashcards

Case 3 Flashcards

1
Q

What happens to the epithelium in Barrett’s oesophagus?

A

Changes from non keratinised stratified squamous to simple columnar.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What happens in a femoral hernia?

A

Abdominal contents go through the femoral ring (which is medial to the femoral vein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Biliverdin is reduced by what enzyme to get bilirubin?

A

Biliverdin reductase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What causes dark urine?

A

Build up of conjugated bilirubin the urine.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the substance that gives faeces its characteristic brown colour? How is it formed?

A

Stercobilin Conjuagted Bilirubin is modified by bacteria into urobilinogen (colourless) Urobilinogen is oxidised into Stercobilin giving faeces its brown colour.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

At rest, how much gastric juice is present in the stomach?

A

30ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the role of somatostatin receptors?

A

Activate Gi protein to decrease PKA and help switch off acid secretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is the action of Ricampicin in terms of protein synthesis?

A

Used to treat TB by blocking bacterial RNA polymerase i.e. interferes with RNA synthesis so mycobacterium tuberculosis can no longer multiply.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is an entergastrone? Examples?

A

Any hormone secreted by the mucosa of the duodenum in the lower GI tract in response to dietary lipids that have some inhibitory action. E.g. GIP, Secretin, CCK, Somatostatin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What five steps are involved in drug induced liver damage?

A

Hepatic pattern

Cholestatic pattern

Fatty injury

Fibrosis

Neoplasms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What drugs are linked to each of these stages of drug induced liver damage?

Hepatic pattern

Cholestatic pattern

Fatty injury

Fibrosis

Neoplasms

A

Hepatic pattern –> paracetamol

Cholestatic pattern –> antibiotics

Fatty injury –> antiepileptics

Fibrosis –> methotrexate

Neoplasms –> anabolic steroids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Classical pain sign for pancreatitis?

A

Pain that radiates from the front to the back.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

How does parasympathetic stimulation influence salivary gland secretion?

A

Increases the rate of production of primary secretion. Increases blood flow.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are Brunner’s glands found?

A

Duodenum only (secrete alkaline mucous)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What hormone is released when calcium levels are low? Name one possible cause of low calcium.

A

PTH. Vitamin D deficiency – it is involved in calcium absorption in the GI tract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What hormone is released when calcium levels are high?

A

Calcitonin. Stimulates calcium deposition in the bones and reduces calcium uptake in the kidneys.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

In salivary secretion, there are two steps, 1) the primary secretion 2) secondary modification. Where does each take place? How do they differ in composition?

A

Primary secretion:

Formed in acinar cells.

The active transport of Na+, K+ and Cl- into the acinar cells drags water with it (by osmosis).

ISOTONIC to plasma.

Secondary secretion:

Takes place as secretion moves from acinar cells to th duct cells.

Na+ & Cl- reabsorbed (into duct cell from lumen)

K+ & HCO3- excreted (from duct cell into lumen)

Duct cells are impermeable to water therefore the fluid is HYPOtonic to plasma.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How does the parasympathetic system affect salivary secretion?

A

Increases blood flow to the salivary glands

= increases secretion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How does the sympathetic system affect salivary secretion?

A

Reduces blood flow to the salivary glands via vasoconstriction =

decreases secretion (dry mouth)

20
Q

What is the difference between

a) Incidence
b) Prevalence

A

Incidence = number of new cases per year (%)

Prevalence = number of cases present at any one time in a given population.

21
Q

What is the ratio of fat:lipoprotein in

LDL and HDL?

A

LDL = high fat: low lipoprotein.

(job: transports cholesterol from liver to tissues)

HDL = low fat: high lipoprotein.

(job: transports cholesterol from tissues to liver)

22
Q

How would you treat ulcers that have been caused by H.pylori?

A

3 - 2 - 1

3 drugs:

Proton pump inhibitor

2 antibacterials e.g. amoxicillin & clarithromycin.

2 times a day

1 week

23
Q

What type of peptidase is Carboxypeptidase?

A

exopeptidase - it can cleave terminal peptide bonds.

24
Q

What type of peptidases are Pepsin, Trypsin, Chymotrypsinogen & Elastase?

A

endopeptidases - cleave internal peptide bonds.

25
Q

Which sympathetic nerve innervates the ileum and jejunum?

A

Lesser splanchnic nerve

The lesser splanchnic nerve is distributed via the branches of the superior mesenteric artery and it supplies the same structures.

26
Q

What layers have to be breached for it called to called an ‘ulcer’ in the stomach?

A

Epithelium, lamina propria, muscularis mucosa, and submucosa

27
Q

What are the three indentations in the oesophagus that can be seen during a barium swallow?

A

Aortic arch

Left main bronchus

Left atrium

28
Q

Describe what ions are absorbed / secreted in salivary secretion.

A

Acinar cells secrete a large volume of isotonic-like fluid rich in NaCl.

This generates a trans-epithelial osmotic gradient drives water flow through apical AQP5 and possibly paracellular pathways.

Ductal cells, relatively impermeable to water, re-absorb NaCl and secrete K+, HCO3-.

29
Q

Describe what ions are absorbed / secreted in pancreatic secretion.

A

In acinar cells, an enzyme rich Cl- secretion is formed (stimulated by AcH, Gastrin, CCK). Hypertonic secretion.

Duct cells are permeable to water. HCO3-/Cl- exchange (stimulated by secretin) .Iso-osmotic secretion.

30
Q

What does CYP2E1 metabolise?

A

alcohol

31
Q

Name the CYP450 enzymes that take part in the CYP pathway of paracetamol metabolism.

Product of the pathway?

A

CYP2E1 and CYP1A2

N-acetyl-p-benzoquinone imine (NAPBQI)

is the toxic species produced. It is deactivated by conjugation with glutathione.

32
Q

What is a ‘toxic dose’ of paracetamol?

What is the lethal limit for paracetamol overdose?

Treatment managment for arriving in A&E within 4 hours of an overdose?

A

4g - 6g

12g

Patients presenting less than four hours after ingestion of a large quantity of paracetamol should receive activated charcoal to reduce absorption. The first paracetamol level should be drawn four hours after ingestion. Treatment with N-acetylcysteine within 8 hours guarantees survival in any case and should also be started as soon as impossible.

33
Q

What is a dangerous side effect of the drugs cimetidine (H2 receptor antagonist)?

A

It inhibits the CPY450 enzymes which can impair the metabolism of e.g. warfarin ( –> increased bleeding)

34
Q

One way to try and reduce alcohol consumption in alcoholics is to give them alcohol sensitising drugs. What do they do?

A

They cause an unpleasant reaction when combined with alcohol due to increased concentrations of acetaldehyde.

35
Q

Name the enzyme that normally breaks down alcohol.

In chronic alcoholics, alcohol is metabolised by another pathway - ?

A

Aldehyde dehydrogenase.

CYP2E1 (same enzyme for making NAPBQ1)

This is why drinking alcohol with paracetamol reduces liver damage because alcohol competes with paracetamol for CPY2E1 but if you drink alcohol before hand, CPY2E1 is upregulated so more NAPBQ1 can be produced.

36
Q

A unit of alcohol (1 unit) = ? mls of pure alcohol.

What is the recommended number of units for a man and woman in a week?

A

1 unit = 10ml pure alcohol

Woman = 14 units (2/day x 7)

Man = 21 units (3/day x 7)

37
Q

What does CYP3A4 metabolise?

A

Around half of all phase 1 matabolites.

38
Q

What does CYP1A1 metabolise?

A

prefers to metabolise theophylline

39
Q

What does CYP1A2 metabolise?

A

Caffeine and theophylline

40
Q

What does CYP2E1 metabolise?

A

alcohol

41
Q

What are the four stages of alcoholic liver disease?

A

fatty infiltration

iflammation

fibrosis

cirrhosis

The damage is reversible until the fibrosis which is irreversible.

42
Q

What receptor / G protein does Secretin act through to cause secretion (pancreatic)?

A

Gs

AC –> cAMP –> binds and activates PKA which phosphorylates Cl- channels

(HCO3- / Cl- exchange)

43
Q

What are the main indicators for acute pancreatitis in serological tests?

A

Raised amylase / lipase

up to x3 the normal amount

44
Q

during saliva secretion the initial secretion is… (a)… and the final secretion is ….(b)…

A

a=isotonic

b=hypotonic

45
Q

In Gillbert’s & Crigler-najjar syndromes, mutated or deleted ………. results in a buildup of ……….. bilirubin and hence ………. in the patient.

A

UGT1A1

unconjugated bilirubin

jaundice

Year 1 (PCS & Cases 1-6) (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions