8/21/13 Flashcards
A genetically meaningful family history includes at least how many generations of family?
3
Consanguinity increases the likelihood of ________
rare and ultra rare autosomal recessive disorders
Forbids using genetic information to deny health insurance, but does not apply to life insurance or disability insurance
GINA, 2008
A decrease in cell size
atrophy
An increase in cell size
hypertrophy
An increase in mitosis that results in a greater number of cells
hyperplasia
A change in the state of differentiation of a cell in response to a stress
metaplasia
In response to stress, lower esophagus changes from stratified squamous to columnar cells like stomach and intestinal mucosa
Barett’s Esophagus
Cell injury most often affects these 5 cellular targets
cell membranes, ER, mitochondria, genetic apparatus, cytoskeleton
Cell injury nearly always involves these 3 key biochemical events
loss of calcium homeostasis, ATP is depleted, and generation of oxygen-derived free radicals
Mechanism of hypertrophy
receptor mediated gene activation leading to increased synthesis of structural proteins
Increased mitosis and DNA synthesis is the mechanism for this
hyperplasia
What keeps the calcium concentration higher outside the cell?
Ca, Mg-ATPase
How does the increase in intracellular Ca due to cell injury affect the cell?
Activate proteases and phospholipases which damage the cell and organelle membranes, leads to the degradation of stores of ATP by ATPase, and activate endonucleases which begin to fragment nucleic acids
Low oxygen and high AMP levels in anaerobic conditions lead to an increase in the activity of these enzymes
phosphofructokinase and lactate dehydrogenase
Name three types of molecules that help prevent free radical accumulation in the body
Scavenger enzymes, GSH peroxiades, antioxidants
3 targets of free radical injury
single strand breaks in DNA, protein crosslinking, lipid peroxidation of membranes
Two ways for chemical injuries
Direct combination, conversion
How does carbon tetrachloride affect liver cells
It is converted to a free radical by P450 in the membrane of the smooth ER, the free radical then attacks the membrane (lipid peroxidation) which leads to more free radicals. The RER swells and ribosomes leave and so there are less apoproteins, which leads to the accumulation of triglycerides in the hepatocytes.
Loos of blood supply due to impeded arterial flow or reduced venous drainage
Ischemia
Oxygen deficiency
Hypoxia
Causes of hypoxia besides ischemia
respiratory insufficiency, tumor growth, CO poisoning, anemia
Why is ischemia worse than the other causes of hypoxia?
The blockage of glycolytic substrates
Calcified mitochondria, chromatin clumping in the nucleus, and cytoskeleton damage may signify
Cell death
Alcoholic cirrhosis can cause mitchondria to become____
Megamitochondria
Swelling of the nucleus leads to fading, which is called____
Karyolysis
Darkening in nucleus due to chromatin condensing is called______
Pynknosis
Breaking up of the nucleus
Karyorrhexis
Karyolysis, Pynknosis, and Karyorrhexis in the nucleus indicate_____
Cell death
Mitochondrial change that triggers cell apoptosis
leakage of cytochrome c
