pathology 1st quiz Flashcards
What characterizes pyknosis?
Nuclear shrinkage, round shape, dark blue/black with H&E stain, nucleolus not visible
What cells are highly vulnerable to to acute cellular swelling?
Cardiac myocytes, proximal renal tubule cells, hepatocytes, endothelium,
What microscopic changes happen during karyorrhexis?
Chromatin breaks up, scattered. Happens in purulent exudate when neutrophils break up.
What is karyolysis?
Lysis of nuclear Chromatin and leaks out of nuclear membrane.
What 2 changes can happen during necrosis of cytoplasm?
- Increased eosinophilia of cytoplasm (basophilia are lost, eosin binds to denatured intacytoplasmic proteins)
- Depletion of glycogen - glassy homogenous appearance
Where is coagulative necrosis usually seen?
Infarcts from loss of blood supply
Toxic products of certain bacteria like nerobacillosis
Poison, burns, electricity, X-ray
What causes zenkers necrosis?
Certain infections Animals fed coffee senna and coyotillo plant White muscle dz Gossypol alkaloid in pigs Malignant hyperthermia
Where does liquefactive necrosis ( colliquative) occur?
Cns, and abscesses
What characterizes fat necrosis both grossly and microscopically?
Gross- white firm chalky
Micro-large shadowy outline of fat cells
Which animals get peritoneal fat necrosis and why?
Young cattle - tall fescue grazing with fungus
Cattle, sheep, horses - summer fescue toxicosis, severity increases with hot weather
Where can traumatic fat necrosis occur?
Fat under skin and pelvic canal
What are the mechanisms of disposal of necrotic tissue?
Liquefaction by Auto lysis and heterolysis, removal by blood and lymph
Liquefaction with abcess formation
Encapsulation by fibrous tissue
Desquamation and sloughing - surfaces, intestine, brochi, renal tubes
Calcification
How can dry gangrene occur?
Loss of blood supply
In ergot poisoning
Tight bandage
Excess cold
Where is dry gangrene mostly found?
Extremity of tail, ear or limb
Where can moist gangrene occur and why?
Lung - aspiration pneuomonia
Intestine - torsion, cuts blood supply
Mammary gland - mastitis caused by putrefaction bacteria
How does gas gangrene occur?
Anaerobic bacteria penetrating wounds or spread from intestine
What are the 4 morphological features of apoptosis?
Cell shrinkage
Chromatin condense, fragment into apoptosis bodies
Phagocytosis of cell by macrophages
No inflammation
Timeline for rigor mortis
1 to 6 hrs after death and persists for 1 to 2 days
What term is used for cooling of the cadaver after death?
Algor mortis
What is livor mortis?
Hypo static congestion - pooling of blood on one side of the animal
where does hemoglobin imbibition occur?
heart and arteries. - red staining of tissues by lysed rbcs
can occur in acute intra vascular hemolysis
when does bile imbibition occur?
1-6 hours after death adjacent to gsll bladder
term for blue green discoloration of tissues by iron-sulfide. takes 18-24 hours
pseudomelanosis
what are pale foci on the liver caused from?q
increasEd intra abdominal pressure
bacterial action from tthe gut into portal vein