Flashcards in 9.19 Injury, Inflammation, Healing 1 Deck (44)
The overall health of the cells impacts its ability to
- resist microorganisms
- recover from injury
Age-associated deterioration of cells leads to
Aging cells are less resistant to
Pathologic changes associated with aging vary widely from person to person, but usually involve:
a lack of functional reserve due to tissue or organ atrophy
What are the three theories on cellular aging?
- free radical theory
- telomere aging clock theory
- wear and tear theory
free radical theory
- oxidative process damages DNA
- produces an excess of free radicals
telomere aging clock theory
molecular clock signals senescence
What is senescence?
cells entering a dividing state
What can telomere dysfunction potentially tell us?
could be used as a malignancy marker
What may act as antioxidants? Why is this important?
- diet, exercise, hormones
- enhance the ability to resist aging
implications of research on improving aerobic capacity on aging?
increase in mitochondrial capacity in skeletal and cardiac muscle
wear and tear theory
heart and brain (organs with less regenerative capacity), signs of aging occur with use over time
What are the mechanisms of cell injury?
- nutritional factors
- physical factors
- mechanical factors
- chemical factors
blood flow insufficient to maintain metabolic function
ischemia can result in
What is a danger with infection?
sepsis can occur
What is sepsis?
- microorganisms or toxins have reached the level that they have spread through the body
- In the bloodstream
mechanisms of cell injury: immune
- autoimmune disorder
What are examples of immune contributing to cell injury?
- type I diabetes
Type I diabetes: What is happening?
antigens produce T-lymphocytes to attack islet cells
mechanisms of cell injury: genetic
(3 separate mechanisms)
interact with environment
Examples of genetic mech of cell injury
- Down's syndrome
- sickle cell anemia
- diabetes (Type II greater than Type I)
genetic considerations: proteins
single mutation in a gene causes an abn folding of a proteins
mechanisms of cell injury: nutritional factors
- malnutrition limits cell replication
- vitamin or mineral deficiencies
Kwashiorkor caused by
Marasmus caused by
general calorie deficiency
mechanisms of cell injury: physical factors
i.e. brain injury, sunburn, frostbite
mechanisms of cell injury: mechanical factors
adaptation vs. injury
- repeated stress
- single high load stress
mechanisms of cell injury: repeated stress
load, rate, forces (torsion, shear)