Patho final lec 1 Flashcards
What are the 2 types of cell death?
-Necrosis: unprogrammed death
-Apoptosis: programmed death
What are some forms of adaptation?
-Hypertrophy
-Atrophy
-Hyperplasia
-Metaplasia
Long-term adaptation to stress can cause cell injury.
What is hypertrophy?
Increase in cell size and functional capacity.
It can become pathologic eg heart hypertrophy.
What are some stimulants of hypertrophy?
-Hormonal stimulation
-Growth factors
-Increased functional demand like in hypertension.
What is an aortic stenosis?
When the aortic valve narrows and blood cant flow normally.
What happens to the heart after long periods of:
1- hypertension
2- aortic stenosis
1- Muscle hypertrophy to increase cardiac output (pathological adaptation)
2- Mix of muscle cell necrosis and hypertrophy due to lack of circulation to the heart cells.
Why does the heart undergo hypertrophy instead of hyperplasia?
Myocytes cannot divide by mitosis and there are few progenitor cells present in the heart, so the heart adapts by increasing cell size.
What organ can undergo physiological mix of hypertrophy and hyperplasia?
Uterine smooth muscle by stimulation of estrogen. (reversible)
What are some stimulants for physiologic hyperplasia?
Hormonal stimulation (breast in puberty)
Compensation of damage (eg liver via GFs)
What are some pathologic hyperplasia inducers?
Viral infections (warts from HPV)
Excessive hormonal stimulation
What are some examples of hormonally stimulated pathologic hyperplasia?
Endometrial hyperplasia (estrogen)
Benign prostatic hyperplasia (androgen)
What are some causes of atrophy?
-Decreased work load
-Loss of innervation
-Diminished blood supply
-Inadequate nutrition (skeletal muscle)
-Loss of endocrine stimulation (uterine smooth muscle)
-Aging (could be due to lower blood supply like in ischemia).
What are some risk factors for atrophy?
-Physical trauma damaging cells or nerves
-Diabetic neuropathy
-Diminished blood supply in diabetic patients and people with atherosclerosis
-Aging due to increased risk of ischemic disease which diminishes blood supply.
What is metaplasia?
The reversible change of a differentiated cell type to another in order to better cope with a stressor.
Is the programming of stem cells to differentiated cells considered metaplasia?
No
What is a common risk after developing metaplasia?
Developing cancer
What are some stressors that cause metaplasia?
-Gastroesophageal reflux disease
-Vitamin A deficiency
-Smoking
What is the common type of metaplasia in the bronchi?
Columnar epithelium —> simple squamous.
Why does vitamin A deficiency increase risk of metaplasia in the bronchi?
Vitamin A is needed for normal epithelial differentiation
What is the type of metaplasia happening in a smoker and why does the body respond that way?
ciliated pseudostratified to non-ciliated simple squamous which may be more protective from harmful smoking gases
What is the difference between hypoxia and ischemia?
Ischemia the condition when blood doesn’t reach the tissue, which makes the cells hypoxic (no oxygen).
What are the causes of cell injury?
-Oxygen Deprivation
-Chemical Agents
-Infectious Agents
-Immunologic Reactions
-Genetic Factors
-Nutritional Imbalances
-Physical Agents
-Aging
What are some causes of oxygen deprivation?
-Ischemia
-Asthma
-High altitudes
-Anemia
What are some chemicals that lead to cell damage?
-Pesticides and herbicides
-Strong acids or alkalis
