Notesale: Turn your study into money

Document Preview

Extracts from the notes are below, to see the PDF you'll receive please use the links above

---

Cellular Injury Causes
1
...


Which type is most common? Which has the most severe effect? Is genetic cell injury worse as it cannot be
altered by behaviours? Are there treatments for the genetic disorders underway?

What are the major causes of cell injury? Give examples
...

There are three main causes of cellular injury; congenital, acquired and genetic
...
This can include physical or chemical agents, infections, immunological responses
poor nutrition, hypoxia and ischemia
...

No oxygen > creatinine kinase anaerobically metabolises creatinine phosphate > glycogen depletion > lactic acid
+ inorganic phosphates
...

REVERSIBLE: Cell oedema + increased acid (acidosis) > clumping of nuclear chromatin > bulges in plasma
membrane (blebs) > mictochondrial swelling
...

Cytosolic calcium increase > released from intracellular stores + influx across the membrane > activates
enzymes
Phospholipases: disrupt cell membrane
...

Endonucleases: DNA and chromatin fragmentation
...
(Study depleting extracellular calcium found delayed cell death after hypoxia)
Ischemia reperfusion
...

One study found that thrombolytic therapy lead to an increase in transient focal cerebral ischemia (stroke)
...
This was found to be
associated with nitric oxide synthases, therefore inhibitors of this NOSs could help to prevent infarction and
haemorrhage
...
ncbi
...
nih
...

This can lead to further myocardial reperfusion injury



















Ischemia is associated with inflammation
...




Physical agents: extreme temperatures
...
Radiation, trauma and electric currents may
also cause physical damage
...

Deletion of DNA segments is the predominant form of radiation damage in cells that survive irradiation
...

Electrocution causes severe burns, it is conducted through ionised fluids in the blood and tissues
...
Tissue freezes> proteins are denatured and the cell dies
...










Chemical agents: immediate damage or long term exposure
...
On the other hand, chronic exposure to a chemical such as ethyl alcohol can lead to cirrhosis of the
liver
...

Individuals who inherit variants in genes encoding for cytochrome p-450 can catabolize at different rates
making them less affected by toxins
...

Depletion of atp to less than 5-10% affects critical cellular systems
...


Infectious agents can directly cause cell death or indirectly throughout the immune response
...
HPV
...
Obesity can cause diabetes and cardiovascular disease
...
Lack of iron can cause anaemia and vitamin d deficiency leads to irregular
bone development
...
Autoimmunity is when the
compnents of the immune system fail to have a tolerance to self and therefore end up attacking the body’s own
cells
...

Genetic disorders that cause cell injury are due to abnormalities in the DNA base sequence
...
The mutation in the haemoglobin gene results in abnormal curved shaped
of the blood cells causing them to get blocked in the blood cells and therefore preventing or limiting the blood
flow
...


Huntingtons disease: The mutation leads to an abnormally large protein which is broken down into toxic
fragments which bind together and accumulate in the neurones causing loss of function
...

Cystic fibrosis: Thick mucus in lungs, multiple infections, difficult to digest and absorb nutrients
...
There is increase of sodium making the mucus sticky
...
Over
1100 different mutations associated, just need one to create faulty CFTR
...

Congenital Disorders are diseases that are present at birth and are caused by cellular defects in development
processes
...

Not always genetic

---