Children with Renal Abnormalities

Question 1

What do all sex cells (sperm and oocytes) start out as?

Answer 1

• gametes

- haploid cells

Question 2

What are the 3 layers of the trilaminar germ disk?

Answer 2

• ectoderm (top)
• mesoderm (middle)
• endoderm (bottom)

Question 3

List a few things that the 3 layers of the trilaminar germ disc will go on to develop?

Answer 3

• ectoderm = skin, eyes, brain
• mesoderm = muscle, RBCs, heart
• endoderm = GIT tract, lungs, pancreas

Question 4

Stem cells will develop into a specific tissue following cell signalling, which is facilitated through transmembrane receptors. What are the 4 types of transmembrane receptors?

Answer 4

1 - Ion channels (cholinergic nicotinic receptors)
2 - GPCR (alpha adrenoreceptors)
3 - enzyme linked receptors (insulin receptors)
4 - intracellular receptors (steroid receptors)

Question 5

There are 4 main methods cells are able to communicate with one another, what are they?

Answer 5

1 - endocrine (signals are sent in the blood)
2 - autocrine (self signalling cell)
3 - gap junctions (physical contact)
4 - paracrine (close cells are signalled)

Question 6

What are transcription factors?

Answer 6

• specific proteins able to bind directly with DNA

- they can promote or inhibit a gene from DNA to mRNA

Question 7

Transcription factors are specific proteins that are able to bind with DNA. They can promote or inhibit a gene from DNA to mRNA. Hox proteins are a group of transcription factors, what is the role of Hox proteins?

Answer 7

• conserved through evolution

- embryonic development by activating and repressing genes

Question 8

In addition to transcription factors that can affect if a gene is active or inactive, ultimately determining if a protein is created, can proteins be altered once they have been synthesised?

Answer 8

• yes
• can undergo methylation, hydroxylation etc…
• all will change a proteins shape, function and interactions with other proteins

Question 9

What are WNT or wingless genes?

Answer 9

• gene identified to be crucial in flys

- if the gene is knocked out or mutated then the fly will develop without wings

Question 10

WNT or wingless genes are genes that have been identified to be crucial in flys. If the gene is knocked out or mutated then the fly will develop without wings. WNY signals bind with frizzled transmembrane cell surface receptors (GPCR) and are involved in what?

Answer 10

• body patterning, cell fate and cell proliferation and migration

Question 11

WNT or wingless genes are genes that have been identified to be crucial in flys. If the gene is knocked out or mutated then the fly will develop without wings. WNY signals bind with frizzled transmembrane cell surface receptors (GPCR) and are involved in body patterning, cell fate and cell proliferation and migration. If there is a mutation or impaired function of WNT genes, what can this cause in humans?

Answer 11

• limb, eye, genitourinary and bone development disorders

- resulting in congenital abnormalities

Question 12

What are notch proteins?

Answer 12

• important cell signalling proteins
• crucial for cell differentiation and maintaining stem cell population (sperm)
• crucial for T cells, neural, endothelial and cardiocytes

Question 13

What are hedghog proteins?

Answer 13

• family of proteins crucial for body patterning roles
• able to bind and signal cells to perform different functions
• how it affects the cell depends on proliferation stage of the cell, dosage of hedghog receptors and cell type

Question 14

Hedgehog proteins are a family of proteins crucial for body patterning roles and are able to bind and signal cells to perform different functions. How hedgehog affects the cell depends on proliferation stage of the cell, dosage of hedgehog receptors and cell type. If there is any mutation of defect in the genes encoding these proteins, what can this cause in humans?

Answer 14

• sonic hedgehog homologue is most important
• important in neural, bone, limb and kidney development; muscle, patterning; and lung branching
• important for special sense organs

Question 15

What are Fibroblast growth factors (FGF)?

Answer 15

• cell signalling proteins produced by macrophages
• involved in a wide variety of processes, most notably as crucial elements for normal development in animal cells
• involved in limb and neural development, angiogenesis, very early patterning and induction of mesoderm development

Question 16

What is transforming growth factor β (TGF-β)?

Answer 16

• highly pleiotropic protein called a cytokine

- important in wound healing, angiogenesis, immunoregulation, cancer and DNA transcription

Question 17

Which part of the trilaminar germ disc does the urinary tract derive from?

Answer 17

• mesoderm

Question 18

The urinary tract derives from the mesoderm. A condensation of cells forms in the abdomen either side of the aorta, which will then go on to develop the urinary tract and reproductive system. What is this called?

Answer 18

• urogenital ridge

Question 19

The urinary tract derives from the mesoderm. A condensation of cells forms in the abdomen either side of the aorta, which will then go on to develop the urinary tract and reproductive system, called the urogenital ridge. This will contain 2 main parts, what are they called?

Answer 19

• nephrogenic cord and the gonadal ridge

Question 20

There are 3 structures involved in kidney development that grow from the intermediate mesoderm in an anterior to posterior sequence. Label the image below with the 3 structures, using the labels below:

• metanephros
• pronephros
• mesonephros

Answer 20

1 - pronephros
2 - mesonephros
3 - metanephros

Question 21

There are 3 structures involved in kidney development that grow from the intermediate mesoderm in an anterior to posterior sequence

• pronephros
• mesonephros
• metanephros

Of the 3 structures, which one will ultimately go on to develop the upper urinary system and what happens to the other 2 structures?

Answer 21

• metanephros = upper urinary system (kidneys)
• pronephros = week 3 forms primitive non functional kidneys before disappearing due to evolution
• mesonephros = disappearing due to evolution

Question 22

From the 3 structures below that are involved in kidney development, as below, which structure at week 4 forms the first functional form of the kidneys?

• pronephros
• mesonephros
• metanephros

Answer 22

• mesonephros

Question 23

At week 4 the first functional form of the kidneys forms from the mesonephros. There are ducts that are formed called mesonephric ducts (Wolffian ducts) are epithelialined tubes that form in the intermediate mesoderm and extend caudally to the cloaca. As the embryo continues to develop, what will these mesonephric ducts develop into?

Answer 23

• renal corpuscles develop from mesonephric tubules into Bowmans capsule
• capillaries from the dorsal aorta form the glomerulus
• lateral end of the mesonephric duct discharges into where the bladder will form

Question 24

Once the ureteric bud, which will go on to form the adult kidney is formed from the mesonepheros, it grows into the surrounding intermediate mesoderm inducing cells in that region to form what over the ureteric bud?

Answer 24

• metanephric cap formed from the metanephros

- forms at week 5

Question 25

The metanephros will ultimately form the kidneys that is attached to the mesonepheric tubule in the form of the uteric bud. The ureteric bud and metanephric cap then begin to develop what?

Answer 25

- ureteric bud forms collecting tubules and the ureter | - cells of the metanephric cap form nephrons that then link to the collecting tubules

Question 26

As the ureteric bud forms collecting tubules and the cells of the metanephric cap form nephrons that then link to the collecting tubules, blood capillaries begin to form through angiogenesis in the Bowmans capsule from what blood vessel?

Answer 26

- dorsal aorta

Question 27

As the ureteric bud forms collecting tubules and the cells of the metanephric cap form nephrons that then link to the collecting tubules, blood capillaries begin to form through angiogenesis from the dorsal aorta into the Bowmans capsule. As the kidneys continue to develop, what will these capillaries then become?

Answer 27

- glomerulus

Question 28

When do functional renal units begin producing urine normally?

Answer 28

- week 12

Question 29

Which cavity do the kidneys develop in during embryology?

Answer 29

- within the pelvic cavity | - then migrate to the lumbar region until they reach T12-L3

Question 30

As the kidneys migrate from the pelvic cavity to the lumbar region of the abdominal cavity, where do the kidneys receive their blood supply from?

Answer 30

- common iliac artery or the aorta | - these will eventually become the renal arteries from the aorta

Question 31

What is the cloaca?

Answer 31

- a common chamber into which some or all of the digestive, urinary, and reproductive tracts discharge their contents during embryological development

Question 32

The cloaca is a common chamber into which some or all of the digestive, urinary, and reproductive tracts discharge their contents during embryological development. The cloaca will develop by week 4 and be separated by urorectal septum and form what 2 structures?

Answer 32

1 - urogenital sinus | 2 - dorsal anal canal

Question 33

The cloaca is a common chamber into which some or all of the digestive, urinary, and reproductive tracts discharge their contents during embryological development. The cloaca will develop by week 4 and be separated by urorectal septum and form the urogenital sinus and the dorsal anal canal. The urogenital sinus can further develop into 3 structures. What are these structures?

Answer 33

1 - top part is the biggest and becomes the bladder 2- middle part forms the urethra in the female pelvis and the prostatic and membranous urethra in the male 3 - lowest part forms the penile urethra in the male and the vestibule in the female

Question 34

What kidney pathology can we see in the image below?

Answer 34

- supernumerary kidneys | - supernumerary ureters (more common

Question 35

What are kidney cysts?

Answer 35

- round fluid filled pouches that form on or in the kidneys

Question 36

Kidney cysts are round fluid filled pouches that form on or in the kidneys. Although there are a number of reasons why they form, in development terms, why do they form?

Answer 36

- developing nephrons fail to connect to a collecting tubule in development, - collecting ducts fail to develop

Question 37

Kidney cysts are round fluid filled pouches that form on or in the kidneys. What is the term used when someone is born with lots of cysts on their kidneys?

Answer 37

- polycystic kidney disease (PKD)

Question 38

Polycystic kidney disease (PKD) is a term used to describe when someone is born with lots of cysts on their kidneys. Is this a dominant or recessive disease?

Answer 38

- can be both

Question 39

Polycystic kidney disease (PKD) is a term used to describe when someone is born with lots of cysts on their kidneys and can be dominant or recessive disease. Is the dominant or recessive form more progressive?

Answer 39

- recessive PKD is more progressive and can cause renal failure in children

Question 40

What is renal agenesis?

Answer 40

- a = missing - genesis = development of - lack of development of a kidney during embryological development

Question 41

Renal agenesis is a lack of development of a kidney during embryological development, leaving a child with one kidney. Does this always causes symptoms for the child?

Answer 41

- no - can be symptom free as other kidney compensates - if no kidneys develop this is lethal

Question 42

As the kidneys ascend from the pelvic cavity up to the abdominal artery the renal arteries will eventually form. Accessory arteries can also form. What are the 2 most common supplementary arteries that can form?

Answer 42

- superior polar renal artery (poles because this is where they generally enter the kidneys) - inferior polar renal artery (poles because this is where they generally enter the kidneys) - not dangerous as long as kidneys receive sufficient blood supply

Question 43

As the kidneys move from the pelvic cavity to the abdominal cavity to the lumbar region they can rotate, presenting as an abnormal finding, depicted in the image below. This can cause a number of problems, one of which is where the kidneys face each other and become connected. What is this called?

Answer 43

- horseshoe kidney | - generally does not cause symptoms, but can increase risk of UTIs

Question 44

As the kidneys move from the pelvic cavity to the abdominal cavity to the lumbar region they can rotate, presenting as an abnormal finding. This can cause a number of problems, one of which is where the kidneys face the wrong way and get trapped on what blood vessel?

Answer 44

- generally the inferior mesenteric artery

Question 45

The proximal tubules are most metabolically active and lead to reabsorption what % of the filtrate?

Answer 45

- 60 to 90% of the glomerular filtrate.

Question 46

The proximal tubules are most metabolically active and lead to reabsorption what % of the fNa+ and Cl-?

Answer 46

- 70%

Question 47

The proximal tubules are most metabolically active and lead to reabsorption what % of H+ is excreted?

Answer 47

- 90%

Question 48

If there is no need to assess renal function through blood biochemistry, how do renal problems generally get detected?

Answer 48

- random finding on ultrasound, CT or MRI

Question 49

Aldosterone and anti-diuretic hormone both do what in the kidneys?

Answer 49

- increase Na+ reabsorption - H2O follows Na+ - K+ is excreted