MET EOYS2 Flashcards
A Ptx present with greater span than height & shorter 4th metacarpal. Which of the following is most likely
McCune-Albright Syndrome
Patau Syndrome
Kallman Syndrome
Turners Syndrome
A Ptx present with greater span than height & shorter 4th metacarpal. Which of the following is most likely
McCune-Albright Syndrome
Patau Syndrome
Kallman Syndrome
Turners Syndrome
McCune-Albright syndrome is caused by a mutation on which gene
Kal
GNAS
PIT1
GSP
McCune-Albright syndrome is caused by a mutation on which gene
Kal
GNAS
PIT1
GSP
Diabetic nephropathy causes the creation of which structures in the glomerulus? [1]
Kimmelstiel–Wilson nodules
What effect do SGLT-2 inhibitors have on afferent and efferent arterioles? [2]
Vasoconstriction at afferent arteriole
No effect at efferent (i think)
Which of the following has neuron development through the cribiform plate?
GnRH
TRH
CRH
ADH
Which of the following has neuron development through the cribiform plate?
GnRH
TRH
CRH
ADH
hypothalamic stimulating hormone that causes the release of GnRH
somatostatin
PIT1
kisspeptin
GPR54
hypothalamic stimulating hormone that causes the release of GnRH
somatostatin
PIT1
kisspeptin
GPR54
Name the hypothalamic stimulating hormone that causes the release of GnRH [1]
Kisspeptin
Explain oestrogen positive feedback of puberty cycle for LH / FSH
Gonad makes oestrogen, which has a positve effect on kisspeptin via GPR54 receptor
Kisspeptin neurones stimulate GnRH
GnRH stimulates gonadotrophs, which makes LH & FSH
Describe path of GnRH neurone formation
What two phenotypes that occur if this process occurs innappropiately [2]
GnRH neurones develop in the olfactory epithelium.
During embryonic development GnRH neurones migrate through cribiform plate, guided by Kal protein & migrate to the hypothalamus
(neurones migrate with cells responsible for smell but go to olfactory bulb not the hypothalamus)
Causes a lack of smell and hypogonadism
Describe pathphysiology of Kallman syndrome [3]
Mutation in Kal protein [1]
During embryonic development these cells can’t enter brain: doesnt take neurones to hypothalamus / olfactory bulb
Cross stalk between two sides of the brain is innappropriate (so cant do movements with one hand indivdually)
How would you test for Kallman syndrome? [2]
Have shorter 4th metacarpal:
Test by putting pencil between small finger and middle finger metacarpal:
- Normal person the pencil wont touch if placed there
- Does in Kallman syndrome
Also: have greater span than height
The anterior pituitary reqiures which transcription factors to develop? [1]
PIT1 [1]
What are developmental consequences of being deficient in PIT1? [2]
Hypothyroidism develops to create cretinism
Overall lacks TSH,GH and Prolactin
Label A-F
What type of receptor is GHRH receptor? [1]
Explain what happens when GHRH receptor is activated [2]
GPCR
Alpha subunit:
- cuts off a phosphate / hydrolises GTP to GDP which originally activated the alpha subunit (regulatory step: so that adenylyl cyclase isnt continually switched on
- activates adenylyl cyclase, which creates cAMP: second messenger to activte GH
Explain effect of gsp oncogene with regards to GHRH receptor and human pituitary tumours [1]
GSP oncogene:
Causes a mutant alpha subunit:
- cannot hydrolise GTP to GDP, which results with alpha subunit constantly activating adenylyl cyclase
Which syndrome is created by a mosaic mutation in GNAS gene? [1]
How do they present? [4]
McCune-Albright syndrome
(Cannot be inherited)
Syndrome has classic traid of:
* polyostotic fibrous dysplasia of bone
* precocious puberty
* café-au-lait skin pigmentation
* Acromegaly is seen in about 20% of patients with MA
What is the most common cause of ACTH-indepedent Cushing’s syndrome? [1]
Name two other causes
Exogenous glucocorticoid threapy (steroid therapy)
(e.g. long term inhaler use)
Can be due to adrenal hyperplasia or adrenal tumour
Explain two AEs of using loop diuretics? [3]
Hypokalemia: directly blocks K reabsorption through blockage of NaKCl2
Dehydration
Kidney stones: due to retained Ca in urine
Deafness
What are clinical uses of aldosterone inhibitors? [4]
Hyperaldosteronism (Conns)
Heart failure
Hypokalaemia (from other diuretics)
Cirrhosis
Explain MoA of SGLT-2 inhibitors
Normally SGLT2 allows Na AND glucose to be reabsorbed at PCT
Blocking SGLT2 causes more Na to be delivered to macula densa: here it causes glomerulus afferent arteriole constriction, which normalises GFR. Also causes glucose to be excreted in urine