Cystic Fibrosis

Question 1

CF is a ___ Pattern disease

Answer 1

inharated autosomal ressesive disease

Question 2

CF is most common among

Answer 2

Caucasions whose ancestors came from northern europe

Question 3

CF is the result of a mutation in the

Answer 3

CFTR gene which leads to a defective CFRT protine

Question 4

CF outcomes

Answer 4

does not go away and gets worse with time
usally fatal
median age of survival is 30 (is greatly improved yousto not be expected to live past childhood)

Question 5

CFRT is a

Answer 5

very large glycoprotein found at the cell membrane
Found in epithelial cells (on surfaces of)
cpvers the interal and exteranl body surfacase

Question 6

Cilia

Answer 6

general imunne function

Question 7

goblet cells

Answer 7

secreet mucase, line digestive and resporatory tract, protecting the epithelium

Question 8

CFTR is a member of the __ family

Answer 8

ABC transporter

Question 9

CFTR and R domain

Answer 9

CFTR is a Membrane bound glycoprotein comprised of two, six span membrane bound regions each connected to a nuclear binding factor which binds ATP. Between these two units is an R-domain which is comprised of many charged amino acids.

R domain is regulatory - fhosporlated by kinase, change conformation, so can interact with nuc. binding domains, stimulates hydrolosist of ATP and binding (v nuc binding domains)

Question 10

In normal cells CFTR

Answer 10

allows the release of Cl from cell, transport of Cl helps control movement of water (water is hypo to hyper so as cl out h2o is also out) - keeeping freely flowing mucase

Question 11

Why is CFTR differnt than other ABC transporters

Answer 11

because it acts like a channel

moement of Cl is passive following its gradient
ATP binds and is hydrolised but NOT as transport - is used as ligand to open and close channel

Question 12

conductance rate of ions in CFTR vs other ABC transporters

Answer 12

CFTR is faster because it acts like a channel

Question 13

mutant CFTR

Answer 13

Cl does not move out therefore water oddes not move out an mucass thickens

Question 14

Effects of thick mucas secretions

Answer 14

1. in lungs - prevents cillia on surface of cells from clearning bacteria, causing chronic infections
2. Pancrease - block passageways in pancreas, digestive enzimes (which are made in the pancrease)
   cannot get to intestine

Question 15

CF symptoms

Answer 15

1. Respiratory:
   Chronic pulmonary (lung) disease
   Thick secretions in airway passages
   Breathing problems
   Coughing or wheezing
2. GI:
   Pancreatic insufficiency
   Excessive appetite but poor weight gain (b/c mallabsorbtion, b/c digestive enzymes cannot go where needed)
   Greasy, bulky stools
   Meconium ileus

3.Skin:
Increase in salt concentration of sweat (very little NaCl is reabsorbed)
Salty-tasting skin

Question 16

CF diagnossis

Answer 16

Every state in the U.S. now routinely screens newborns for cystic fibrosis.

Detection of meconium ileus at birth (CF makes difficult to pass)

Blood sample is checked for higher than normal levels of a chemical (immunoreactive trypsinogen, or IRT) released by the pancreas.

Sweat test. - see salt concentration in sweat

Genetic Test: - gene testing

Question 17

immunoreactive trypsinogen

Answer 17

or IRT
is inactive digestive enzyme
because (In CF) blocked can leack out of pancreas into the blood

Question 18

Sweat gland in CF

Answer 18

Cl - goes in, also causes Na to go in (because of attractive forces Na+ Cl-)
Cl need to be reabsorbed but in cf cl is not, causing Na to also not be reabsorbed