Pathology - Fractures and Dislocations

Question 1

Possible outcomes of a normal cell undergoes

Answer 1

Necrosis
Apoptosis
Mixture of necroptosis and pyroptosis

Question 2

Pyroptosis

Answer 2

Mixture of pyrexia (release of IL-1) and apoptosis
Activation of inflammasome
Happens in infl

Question 3

What can damage cells

Answer 3

Oxygen deprivation 
Physical agents 
Chemical agents 
Infectious agents 
Immune agents 
Immune reactions 
Genetic abnormalities 
Nutritional imbalances

Question 4

Physical agents that can damage cells

Answer 4

Mechanical trauma
Extremes of temp
Sudden changes in atmospheric pressure
Radiation

Question 5

Reversible cell injury

Answer 5

Cell swelling 
Fatty change 
Eosinophilia 
Changes to cell membrane 
Mitochondrial swelling 
Dilation of endoplasmic reticulum w/ detachment of ribosomes 
Chromatin clumping

Question 6

Changes to cell membrane that counts `as reversible cell injury

Answer 6

Cell membrane blebbing/ blunting/ loss of microvilli

Question 7

Cell adaptations

Answer 7

Reversible changes in the size, number, phenotype, metabolic activity or functions of cells in response to changes in their environments

Question 8

Types of cell adaptations

Answer 8

Hypertrophy
Hyperplasia
Metaplasia
Atrophy

Question 9

Hypertrophy

Answer 9

Increase in the size of cells that cause an increase in the size of the affected organ
Related to increased workload
May be physiological or pathological

Question 10

Physiological hypertrophy

Answer 10

Can be seen in uterus during pregnancy

Question 11

Pathological hypertrophy

Answer 11

Most commonly seen in myocardium - hypertension/ valvular heart disease

Question 12

Hyperplasia

Answer 12

Increase in the no. cells in an organ/ tissue in response to a stimulus
Can only take place if the cells are capable of dividing

Question 13

Which two adaptations can take place together

Answer 13

Hyperplasia and hypertrophy

Question 14

Stimuli causing hyperplasia

Answer 14

Hormone

Growth factors

Question 15

Metaplasia

Answer 15

Reversible change in which one differentiated cell type is replaced by another cell type

Question 16

What is metaplasia an example of

Answer 16

An adaptive response where the replacement cell type is better able to withstand the adverse environment

Question 17

What is metaplasia caused by

Answer 17

Reprogramming of stem cells

Question 18

Dysplasia

Answer 18

If the stimulus causing metaplasia persists, disordered growth in the epithelium can occur —-> invasive carcinoma

Question 19

Squamous metaplasia

Answer 19

Columnar cell replaced by squamous cell

Question 20

Intestinal metaplasia

Answer 20

Squamous cells replaced by goblet cells

Question 21

Atrophy

Answer 21

Reduction in the size of an organ or tissue due to a decrease in cell size (and size of organelles) and number
Autophagy is activated

Question 22

What pathway is activated in atrophy

Answer 22

Ubiquitin-proteosome pathway

Question 23

Autophagy

Answer 23

Cell eating its own organelles to reduce nutrient demand to meet the supply

Question 24

Pathological hyperplasia

Answer 24

Excessive or inappropriate actions of hormones or growth factors acting on target cells
Drives mature cells or increases output of new cells from stem cells
Hyperplasia regresses if the stimulus is removed

Question 25

Pathological atrophy causes

Answer 25

``` Disuse Denervation Diminished blood supply Inadequate nutrition Loss of endocrine stimulation Pressure ```

Question 26

Disuse atrophy

Answer 26

Due to prolonged bed rest and can be accompanied by osteoporosis

Question 27

Denervation atrophy

Answer 27

Damage to nerves supplying a muscle

Question 28

Diminished blood supply causing atrophy

Answer 28

Atherosclerosis of blood vessels can cause atrophy

Question 29

Pressure atrophy

Answer 29

An expanding tumour can put pressure on blood vessels causing atrophy of tissues supplied by those vessels

Question 30

Irreversible injury

Answer 30

if the stimulus exceeds the ability of the cell to respond or adapt

Question 31

Necroptosis

Answer 31

Has features of both necrosis and apoptosis

Question 32

Inflammasome

Answer 32

A danger-sensing protein complex within the cytoplasm of the cell

Question 33

Necrosis

Answer 33

Accidental/ unregulated form of cell death Damage to membranes – lysosomal enzyme digestion of cell Leakage of cell contents causing inflammatory reaction Always pathological

Question 34

What can necrosis be caused by

Answer 34

Ischaemia Toxins Infections Trauma

Question 35

Mechanisms underlying cell injury in necrosis

Answer 35

``` Depletion of ATP Mitochondrial damage Influx of calcium Accumulation of ROS Membrane permeability defect DNA and protein damage ```

Question 36

Influx of Ca in cell injury

Answer 36

Leads to depletion of ATP | Activates enzymes causing membrane, protein, nuclear and DNA damage

Question 37

Effects of ROS

Answer 37

Damage proteins, lipids and nucleic acids by attacking and modifying them

Question 38

ROS

Answer 38

Reactive Oxygen Species

Question 39

Apoptosis

Answer 39

A cell death pathway that's induced by a tightly regulated suicide programme in which enzymes are activated that can degrade the cells own DNA and proteins and fragment cytoplasm

Question 40

Physiological apoptosis

Answer 40

Destruction of cells during embryogenesis Involution following hormone withdrawal Cell loss in proliferating cell population Elimination of self-reactive lymphocytes Control of the inflammatory response

Question 41

Apoptosis pathways

Answer 41

Intrinsic (mitochondrial) pathway | Extrinsic (death receptors initiated) pathway

Question 42

Intrinsic pathway of apoptosis initiator

Answer 42

Caspase 9

Question 43

What is the intrinsic pathway of apoptosis triggered by

Answer 43

Cell injury, DNA damage or decreased hormonal stimulation

Question 44

Caspases

Answer 44

Proteases which can breakdown cell proteins)

Question 45

Extrinsic (death receptor initiated) pathway initiator

Answer 45

Caspase 8 | Caspase 10

Question 46

What is the extrinsic (death receptor initiated) pathway activated by

Answer 46

FAS ligand binds FAS death receptor (CD95) on the target cell, activating caspases

Question 47

Removal of apoptotic cells

Answer 47

Phosphatidylserine Apoptotic cells secrete soluble factors which recruit macrophages Apoptotic bodies get coated w. thrombospondin or bind C1q which attracts macrophages

Question 48

Causes for abnormal accumulation of substances

Answer 48

Inadequate removal, Excessive production of an endogenous substance Deposition of an abnormal exogenous material

Question 49

Steatosis

Answer 49

Fatty change | Caused by build-up of triglycerides, usually in hepatocytes

Question 50

Atherosclerosis

Answer 50

Cholesterol accumulation in macrophagses

Question 51

Dystrophic pathological calcification

Answer 51

Occurs when calcium is deposited in tissue which is injured or dead, calcium metabolism is normal

Question 52

Metastatic pathological calcification

Answer 52

Seen in association w/ hypercalcaemia May be caused by increased parathyroid hormone Vitamin D excess Sarcoidosis

Question 53

Sarcoidosis

Answer 53

Disorder where macrophages accumulate in granulomas (round nodules) and these macrophages activate a Vit D precursor causing hypercalcaemia

Question 54

Pathological features of non-union

Answer 54

Malformed callus can undergo cystic degeneration | Becomes lined with synovial-like cells creating a false joint (pseudo-arthrosis)