MoD

Question 1

What are the reversible changes caused by Hypoxia?

Answer 1

• Low ATP causes Na to accumulate in cell causing swelling
• Chromatin clumping due to decrease in pH caused by increased anaerobic respiration
• Blebbing

Question 2

What are the irreversible changes caused by Hyposia?

Answer 2

• Massive accumulation of Ca
• Nuclear changes
• Lysosome rupture

Question 3

Define Necrosis

Answer 3

Changes that occur after cell death in living tissue

Question 4

What is Coagulative Necrosis? What tends to cause it?

Answer 4

Firm tissue, produced when there is more protein denaturation than enzymes released. Cellular architecture is preserved so get ‘Ghost Outline’.
Tends to be caused by infarcts

Question 5

What is Liquefactive Necrosis? What tends to cause it?

Answer 5

Tissue is Liquid + pus like, more enzymes released than protein denaturation. Tissue is lysed + disappears.
Tends to be caused by infection

Question 6

What is an Infarct?

Answer 6

Necrosis due to Ischemia

Question 7

What is a White Infarct (Anaemic Infarct)? Where can it be found?

Answer 7

Caused by the occlusion of end artery with no peripheral blood vessels.
Found in Heart, Kidney + Spleen

Question 8

What us a Red Infarct (Hemorrhagic Infarct)? Where can it be found?

Answer 8

Caused by the occlusion of an artery in an area that has dual or collateral circulation.
Found in ‘Loose tissues’ Lungs, Small intestines, testis + ovaries

Question 9

What is Hereditary Angio-Oedema

Answer 9

Caused by deficiency of C1 inhibitor, this normally inhibits both C1 + Bradykinin. Uninhibited Bradykinin increased the permeability of the endothelia causing oedema. Treated with C1 inhibitor infusion

Question 10

What is Chronic Granulomatous Disease?

Answer 10

Recessive Sex linked, Immune Phagocytes can’t form ROS, can’t kill bacteria and form Granulomas to attempt to contain the bacteria

Question 11

What are the effects of Chronic Inflammation?

Answer 11

• Fibrosis (Gall bladder [Chronic cholecystitis], Chronic peptic ulcers, cirrhosis)
• Impaired function (Chronic Inflammatory Bowel Disease)
• Atrophy
• Stimulation of immune response (Macrophage-Lymphocyte interactions)

Question 12

When are Macrophages important? What are their functions?

Answer 12

Important in Acute + Chronic Inflammation
Functions are;
- Phagocytosis + destruction of debris + bacteria
- Presenting antigens to immune system
- Synthesis of cytokines, complement, clotting factors + proteases
- Control of other cells via cytokine release

Question 13

When are Lymphocytes important? What are their function?

Answer 13

Important in Chronic inflammation
Functions are;
- B cells produce antibodies
- T cells - T helper + T killer cells

Question 14

What are the 3 types of Giant cells and when are they found?

Answer 14

Langerhans - TB (Peripheral Nuclei)
Foreign Body Type (Central Nuclei)
Toulon - Fat Necrosis (Ring of Nuclei)

Question 15

What is Rheumatoid Arthritis?

Answer 15

Autoimmune disease where localised chronic inflammation leads to joint destruction

Question 16

Describe the formation of Granulation Tissue

Answer 16

1. Cell Migration - Inflammatory cells (Neutrophils, Macrophages - Phagocytosis. Lymphocytes, Macrophages - Chemical Mediators), Endothelial cells (Angiogenesis), Fibroblasts/Myofibroblasts
2. Angiogenesis - Development of new blood supply. Endothelial proliferation induced by proangiogenic growth factors, e.g. VEGF
3. Extracellular Matrix - Supports + anchors cells, Sequesters growth factors

Question 17

Describe Fibrous Repair

Answer 17

1. Inflammatory cell infiltrate - Blood clot forms. Acute inflammation around edges. Chronic inflammation - Macrophages + lymphocytes migrate into the clot
2. Clot replaced by Granulation Tissue - Angiogenesis, Myo/fibroblasts migrate + differentiate
3. Maturation - Cell population falls, collagen increases, Myofibroblasts contract, vessels differentiate + are reduced

Question 18

What causes the breakdown of Fibrin? What fibrinolytic is widely used and how does it work?

Answer 18

Plasmin causes breakdown of fibrin.

Streptokinase activates Plasminogen

Question 19

What is the treatment for Deep Vein Thrombosis?

Answer 19

• IV Heparin (Anticoagulant)

- Oral Warfarin (Interferes with synthesis of Vit. K clotting factors)

Question 20

What can cause Fat Emboli?

Answer 20

• Fractures of Long Bones

- Lacerations of adipose tissue

Question 21

What can lead to a Cerebral Embolism?

Answer 21

Atrial Fibrillation causes Stasis of blood in atria, causes a thrombus which can go to the brain and cause a stroke

Question 22

What can be the triggers for Disseminated Intravascular Coagulation?

Answer 22

Infection, trauma, liver disease

Question 23

What is Thrombocytopenia?

Answer 23

Platelet count way below reference range, usually accompanied by a bone marrow disfunction (e.g. Leukaemia, anaemia)

Question 24

Name the risk factors for Coronary Heart Disease

Answer 24

• Male
• Smoking
• Hypertension (increased epithelial damage)
• Diabetes
• Alcohol
• Infection (H. pylori)

Question 25

What is an Atheroma?

Answer 25

The accumulation of intracellular + extracellular lipid in the intima and media of large + medium sized arteries