General pathology Flashcards
Cell survival depends on the presence of ……
a balanced environment (homeostasis), with constant supply of energy and active transport processes
Cell injury occurs if …..
the cell can not fully adapt to the insult (change)
* Injury causes reversible changes at the beginning, but may progress to irreversible damage and cell death
The ability of the cell to tolerate injury depends on ….., ….., …… & ……
severity, duration, type of stimuli & the ability of the cell to adapt
Hypoxia leads to insufficient ATP. Low ATP causes ……, ……. & …..
failure of the Na-K pump
increased glycolysis
progressive detachment of ribosomes from the RER
* Hypoxia is caused by
1. Ischemia
2. Reduced blood O2 carying capacity
3. poisoning of the enzymes in the ETC (by cyanide, rotenone, antimycin A “produced by bacteria”)
Chemical cell injury causes ……
disruption of the chemical processes or the physical structure of the cell
Cloudy swelling is …..
results from damage to the ETC complex, leading to low ATP, followed by failure of the Na-K pump, influx of water and Ca, and efflux of K
- ER will be dilated, and ribosomes are detached from its surface
- If ATP supply is not restored, irreversible injury occurs
Production of toxic oxygen intermediates will causes …..
membrane damage
* Also, production of some lipid products may have a detergent like effect on the plasma membrane
Mitochondrial swelling occurs because of …..
Ca accumulation
* This leads to inhibition of oxidative phosphorylation
Karyorrhexis is ……
Karyolysis is …..
- nuclear fragmentation
* dissolution of the nucleus
Coagulation necrosis is ….. . The common causes are ….
the most common type of cell injury for cells with little number of lysosomes
- Homogenous eosinophilic mass with loss of the nucleus but preservation of the cell shape
- Usually caused by thermal or toxin injuries, or sudden ischemia
- The heart is the most common example
- Dry Gangrene is another example
Liquefactive necrosis is ….. . Suppuration is …..
cellular destruction by hydrolytic enzymes. Occurs usually in the brain & pancreas
* suppuration is liquefaction by leukocytic enzymes, and the product is Pus
What is the difference between Autolysis and heterolysis?
- Heterolysis refers to apoptosis induced by extrinsic hydrolytic enzymes
- Autolysis is apoptosis of a cell by its own enzymes.
Casseous necrosis is …..
combination of liquefactive and coagulative nerosis.
- Tissue is grossly soft, friable and cheese like
- It is a characteristic of tuberculosis, granulomas and fungal infections.
- Squamous carcinoma has casseous center due to rapid growth
Spilling of pancreatic lipase on adjacent adipose tissue causes ….
enzymatic fat necrosis
* Occurs due to pancreatic necrosis
Gummatous necrosis is characterized by ……
differs from liquifactive and coagulative necrosis by its gelatin like appearance
* Seen in late stage syphilis
Apoptosis is characterized by …..
- minimal inflammation
- Chromatic condenses (due to low pH), and bleb appear on the cytoplasmic membrane (deformation)
- Break down of DNA into small fragments
- Energy production is not affected
Anthracotic pigmentation is …..
accumulation of coal dust particles in cells
* It is a type of exogenous pigments
Lipofuscin is …..
It is found in …..
What is the source?
a type of endogenous pigments. Also called wear and tear pigments. Appear in the heart, brain & liver. Derived from lipid peroxidation
* Other types of endogenous pigments is hemosidrin, melanin, bilirubin
Dystrophic calcification is caused by ….., while metastatic calcification is caused by …..
- percipitation of Ca phosphate in area of necrosis, due to low pH
- hypercalcemia due to malignancy or hyperparathyroidism
Atrophy is …… and is caused by …..
loss of cell/organ size
- caused by disuse, malnutrition, aging, ischemia, or lack of hormonal or neural stimulation
- Organ atrophy is due to loss of cells, or decrease cell size, or both
Hypertrophy is …..
increased cell/organ size (weight lifters, and cardiac muscle in hypertension)
- Also due to endocrine overstimulation.
- Could be physiologic (lactating breast) or pathologic (cancers)
Hyperplasia is …..
increase in cell numbers, often with hypertrophy
- Nerve, cardiac & skeletal cells can not exhibit hyperplasia
- Physiological (partial hepatectomy, breast growth) or pathological (lymphoid hyperplasia due to antigen stimulation)
Metaplasia is ……
reversible change of one cell type to another due to irritation
* Chronic smoking causes metaplasia of the bronchoalveolar epithelium
What are the cardinal signs of acute inflammation?
- Rubor
- dolor
- calor
- tumor
- loss of function
Transudate is caused by ……., while exudate is caused by ……
- pressure difference between the vasculature and the interstitial space
- due to increased permeability of the vessels and chemotactic factors. Contains proteins and cells
Inflammation begins with vascular …… followed by ……
- transient vasoconstriction
- vasodilation of the affected area (flow will be slow and the vessels leak). caused by histamin, prostaglandin, bradykinin
Increased vascular permeability in acute inflammation is caused by …
contraction of the pericytes (embedded in the basement membrane and wrap around endothelial cells of capillaries and venules)
What is the effect of the following on the vasculature:
- Serotonin
- bradykinin
- leukotriens
- Histamine
- Vasoconstriction, increase permeability
- vasodialtion, increase permeability
- vasoconstriction, increase permeability
- vasodilation, increase permeability
* histamine & serotonin are vasoactive amines. Stored in mast cells, basophils, platelets
* leukotriens cause bronchoconstriction (asthma) and increase mucus secretion in the airway
* Vasoactive amines act specifically on venules (not capillaries)
Extravasation of fluid allows leukocytes to ….
marginate, roll & adhere to the endothelium via specific receptor, form pseudopods between cells, cross the basement membrane towards the stimulus
* This whole process is called diapedesis
An example of bacterial chemotactic factor is ……
N-formylmethionine
The most important chemotactic factors for neutrophils are ….. & …..
C5a & IL-8
Explain phagocytosis
- The particle to be engulfed is opsonized with C3b & IgG
- Binding of the particle to Fc or CR1 receptor on the phagocyte
- Engulfment & binding of the vacuole to lysosome
- Break down of materials with acid, reactive oxygen, proteases & lysozymes
Corticosteroids …… leukocyte migration
inhibits
* Also, stabilizes the lysosomal membranes
The main cells in acute inflammation are ….., and in chronic are …..
neutrophil, mast cells
monocyte (macrophage), lymphocytes, plasma cells
What is the composition of the cellular infiltrate in chronic inflammation??
- Macrophage
- Fibroblasts (collagen deposition resulting in scarring)
- Eosinophils, lymphocytes & plasma cells
- occasionally, some neutrophils