Pathology Flashcards
Cellular Adaptations Cell Injury Free Radicals Apoptosis Necrosis Inflammation Principles Acute and Chronic Inflammation Granulomatous Inflammation Wound Healing and Scar Pathologic Calcification Neoplasia
What are the 4 causes of cell injury?
- Ability to adapt is not enough
- Exposure to harmful substances
- Malnourishment
- Mutation within metabolism
What are the 2 ways cells die?
Necrosis = inflammatory
Apoptosis = non-inflammatory
Ways that a cell can undergo stress
Pathologic: ischemia
Physiologic: Pregnancy
What is cellular adaptation?
Reversible change in response to stress
What happens to the cell if the stressor exceeds it’s ability to adapt?
Cell injury - can be reversible until a given point
What happens when the cell can not adapt to the stressor either reversible or irreversibly?
Cell death
What are the 4 main types of cellular adaptations?
- Hypertrophy
- Hyperplasia
- Atrophy
- Metaplasia
How do cells respond to stress?
Normal —> adaptation —> injury—> death
Hypertrophy is an increase in _________.
Cell size
Hyperplasia is an increase in _______.
Cell number
Atrophy is a decrease in _________.
Cell size
Metaplasia is a change in ___________.
Phenotype
Muscle tissues can only undergo _____________.
Hypertrophy with more workload
What is the main cause for hyperplasia?
Excess hormone stimulation
Breast growth, liver regeneration and bone marrow are all examples of what pathologic mechanism?
Hyperplasia
Growth due to estrogen
Endometrial hyperplasia
Xs response to androgens
Prostatic hyperplasia
2 kinds of HPV
Epidermal hyperplasia = skin warts
Mucosal hyperplasia = genital warts
When is an organ in homeostasis?
When physiologic stress is placed on it
When do growth adaptations happen?
When the physiologic stress on the organ either increases, decreases, or changes
What 2 adaptations result in the organ to become larger?
Hyperplasia and hypertrophy
What is the mechanism of hypertrophy?
Involves gene activation, protein synthesis and production of organelles
What is the mechanism of hyperplasia?
Involves production of new cells from stem cells
What type of tissue can undergo hypertrophy only?
Permanent tissues cannot make new cells
What are the 3 types of permanent tissues?
Cardiac muscle, skeletal muscle, and nerve
What are the dangers of pathologic hyperplasia?
It can progress to dysplasia and cancer - endometrial hyperplasia
EXCEPTION: BPH
What happens when there is a decrease in stress on an organ?
Atrophy
What is the mechanism of atrophy?
Decrease in size and number
What is the mechanism seen in atrophy to decrease cell #?
Apoptosis
How does a decrease in cell size occur during atrophy?
- Ubiquitin-proteosome degradation of the cytoskeleton
- Autophagy of cellular components
What types of tissues cannot undergo hyperplasia?
Cardiac, skeletal, nerve
What causes the proliferation and degradation of the endometrium?
Proliferation - estrogen Degradation - progesterone
How does the cell type change?
Metaplasia of surface epithelium
What is the mechanism of Barrett esophagus?
Esophagus is lined by squamous epithelium and stomach is lined by columnar epithelium. Acid refluxes from stomach into lower esophagus causes a change in stress and epithelium from squamous epithelium to columnar non-ciliated mucinous epithelium
What is the mechanism of metaplasia?
Reprogramming of stem cells
Is metaplasia reversible?
Yes if the stressor is removed(I.e) treatment of GERD
Metaplasia ______ progress to dysplasia and cancer
Can (I.e. Barrett esophagus)
What type of metaplasia does NOT increase the risk for cancer?
Apocrine metaplasia
A deficiency in what fat-sol. Vitamin can cause metaplasia?
Vitamin A
Barrett esophagus increases the risk for what type of cancer?
Adenocarcinoma of the esophagus
What type of metaplasia can be seen in fibrocystic change of the breast?
Apocrine metaplasia
What is keratomalacia?
Vitamin A deficiency causing the conjunctiva of the eye to undergo metaplasia and cause a thickening
Can mesenchymal tissues undergo metaplasia?
Yes (I.e.) myositis ossificans
What happens in myositis ossificans?
Inflammation of skeletal muscle causes a metaplastic production of bone inside the skeletal muscle
What is dysplasia?
Disordered cell growth; proliferation of precancerous cells
How does dysplasia occur?
Longstanding pathologic hyperplasia or metaplasia
What is the moa of endometrial hyperplasia?
Longstanding pathologic hyperplasia
Is dysplasia reversible?
Yes if the stressor is removed
What happens if stress persists in dysplasia?
Progress to carcinoma which is irreversible
What is Aplasia?
Failure of cell production during embryogenesis (I.e. unilateral renal agenesis)
What is hypoplasia?
Decrease in cell production during embryogenesis—> small organ (I.e.) streak ovary in Turner syndrome
Pathologic hyperplasia
Endometrial
