Cell Injury

Question 1

Causes of cell injury

Answer 1

Hypoxia
Ischaemia
Physical agents
Chemicals agents
Microbial agents
Immunologic causes
Nutrition derangements
Ageing
Psychogenic causes
Idiopathic

Question 2

Define atrophy

Answer 2

Reduction in number and size of parenchymal cells of organ or its part which was once normal is called atrophy

Question 3

Eg of physiological atrophy

Answer 3

A trophy of lymphoid tissue with age
A trophy of thymus in adult life
Atrophy gonads after menopause
Atrophy of brain with aging

Question 4

Pathological atrophy

Answer 4

Starvation atrophy
Ischemic atrophy
Dis use a trophy
Neuropathic atrophy example polymyelitis motor neurone disease nerve section
Endocrine trophy example hypopitutism hypothyroidism
Pressure atrophy examples are erosion of spines by tumor in nerve root erosion

Question 5

Hypertrophy

Answer 5

Hypertrophy is an increasing size of parenchymal cell resulting in enlargement of the effected organ or tissue

Question 6

Physiological hypertrophy

Answer 6

Enlarge uterus in pregnancy

Question 7

Pathological hypertrophy

Answer 7

Hypertrophy of cardiac muscle
Due to:
1. Systemic hypertension
2. Aortic disease
3. Mitral insufficiency
Hypertrophy of smooth muscle example
1. Cardiac achalasia
2. Pyloric stenosis
Compensatory hypertrophy of an organ when contralateral organ is removed example following nephrotomy on one side in young patient there is compensatory hypertrophy as well as hyperplasia of the nephrons of the other kidney

Question 8

Hyperplasia

Answer 8

Hyperplasia is an increase in the number of parenchymal cell resulting in enlargement of the organ and tissue

Question 9

Physiological hyperplasia

Answer 9

1.Hormonal hyperplasia examples are enlargement of female breast during pregnancy and lactation and also uterus
2. Compensatory hyperplasia

Question 10

Pathologic hyperplasia

Answer 10

Benign interastatic hyperplasia in old age

hyperplasia of skin in non healing ulcer

Question 11

Metaplasia

Answer 11

Metaplasia is defined as reversible change in one type of mature differentiated epithelial or Mesenchymal to another type of mature epithelial or mesenchymal

Question 12

Metaplasia

Answer 12

Metaplasia is defined as reversible change in one type of mature differentiated epithelial or Mesenchymal to another type of mature epithelial or mesenchymal

Question 13

Dysplasia

Answer 13

Dysplasia means disordered cellular development of preceded or accompanied with metaplasia and hyperplasia. it is therefore also referred to as a typical hyperplasia

Question 14

Steps of reversible cell injury

Answer 14

1. Decrease generation of cellular ATP damaged by ischemia
2. Intercellular lactic acidosis which causes nuclear clamping
   3.damage to plasma membrane pumps
   There is damage to sodium potassium pump which causes hydrox swelling means the swelling of the cell
   There is failure of calcium pump which causes mitochondrial spelling and deposition of phosphor lipid rich amorphous density
3. Reduce Protein synthesis as a result of hypoxia endoplasmic reticulum and Golgi apparatus swell up thus I

Question 15

What are mylien figures

Answer 15

Mylene figures are derived from membrane enclosing water and dissociated lipoproteins between laminate of injured membrane

Question 16

Changes occurring during irreversible cell injury

Answer 16

1. Calcium influx which cause mitochondrial damage disabling its function. Morphologically it appears in the form of vacuole in the mitochondria and deposit of amorphous calcium salt in mitochondrial matrix
2. Activated phospholipase: increased calcium in flux activates phospholipase this intern degrade phospholipid which are main constituent of lipid bilayer membrane
3. Activated intracellular proteases cause cytoskeletal damage. This cytoskeleton microfilaments and intermediate filament can be damaged by proteases or also the result of cell swelling
4. Activated endonuclease cause nuclear damage
5. There is rupture of the lysosomal membrane which causes the release of the lysosomal enzyme and ultimately the cell death

Question 17

Condensation and clumping of nucleus which becomes dark basophilic

Answer 17

Pyknosis

Question 18

Nuclear fragmentation into small BITS dispersed in the cytoplasm

Answer 18

Karyorrhexis

Question 19

Dissolution of the nucleus

Answer 19

Karyolysis

Question 20

Ischaemia reperfusion injury

Answer 20

Due to excessive accumulation of oxygen species or free radical

Question 21

Cytotoxicity of free radical

Answer 21

1. Lipid peroxidation
2. Dna damage
3. Oxidation of proteins
4. Cytoskeletal damage

Question 22

What are antioxidant

Answer 22

Antioxidants are endogenous or exogenous substances which inactive the free radical the substance include
Vitamin e A c
Sulphydryl containing compound eg cysteine and glutathione

Question 23

Oxygen burst

Answer 23

Incoming activated neutrophils utilises oxygen quickly and further release large excess of oxygen free radical

Question 24

What are the two types of stress protein in cell injury

Answer 24

Heart shock protein
Ubiquitin

Question 25

Accumulation of water within the cytoplasm of the cell

Answer 25

Hydropic change

Question 26

Intracellular hyaline

Answer 26

Hyaline droplets in Pct due to protein urea Hyaline degeneration of rectus abdominis muscle called zenkers degeneration in typhoid fever

Question 27

Intracellular hyaline

Answer 27

Hyaline droplets in Pct due to protein urea Hyaline degeneration of rectus abdominis muscle called zenkers degeneration in typhoid fever

Question 28

Necrosis

Answer 28

Necrosis is defined as localised area of death of tissue followed later by degeneration of tissue by hydrolytic enzyme liberated from dead cell it is invariably a company by inflammatory reaction

Question 29

Most common type of necrosis caused by irreversible focal injury mostly from sudden cessation of blood flow

Answer 29

Coagulative necrosis

Question 30

Focus of coagulative necrosis in early stage is pain firm and slightly

Answer 30

Infarct

Question 31

What is the hallmark of coagulative necrosis

Answer 31

Conversion of normal cells into Tombstone that is outlines of cells are retained and type can still be recognise but the cytoplasmic and nuclear details are loss

Question 32

Seen in focal bacterial or, occasionally, fungal infections, because microbes stimulate the accumulation of inflammatory cells and the enzymes of leukocytes digest the tissue.

Answer 32

Liquefactive necrosis

Question 33

The type of necrosis which is found in centre of focib of tubercular infection

Answer 33

Caseous

Question 34

Special form of cell that occurring at mainly fat rich and atomic location in the body

Answer 34

Fat necrosis

Question 35

Examples of fat necrosis

Answer 35

Traumatic fat necrosis of breast especially in heavy and pendulous breast Mesenteric fat necrosis due to acute pancreatitis

Question 36

Fibrinoid necrosis

Answer 36

Fibrinoid necrosis is characterized by the deposition of the fibrin like material which has properties of Fibrin examples are auto immune vasculitis

Question 37

Calcification

Answer 37

Deposition of calcium salts in tissue other than osteoid and enamel is called calcification Dystrophic- necrotic, severe atherosclerosis Metastatic - normal, hypecalemia