General Study Flashcards
Define “Pathophysiology”
The “What”
The physiology behind observed pathological changes.
Define “Pathogenesis/Aetology”
The “Why”
The causal factors of diseases.
Disease is the manifestation of _____ _______.
Cell injury.
Define “Parenchyma”
Specialist cells of a specific organ.
e.g., myocardium in the heart.
Define “Stroma”
The network of connective tissue that acts as scaffolding for parenchyma.
Made of collagen and fibroblasts.
Define “Endothelial Cells”
Parenchyma cells that line the internal walls of blood vessels.
Define “Epithelial Cells”
Parenchyma cells that line the internal walls of organs other than blood vessels.
Define “Atrophy”
The reduction in cell size and function.
Define “Hypertrophy”
The increase in cell size and output.
Define “Hyperplasia”
The increased number of cells.
Define “Metaplasia”
Changes in cell morphology and function.
The cells are still recognisable, however, they are starting to look different and struggle to function.
Define “Dysplasia”
The increased number, change of morphology, and differentiation of cells.
Pre-neoplastic.
What cells produce mucus?
Goblet cells
What chemicals are released when a cell dies?
Lysosomes.
What chemical is released when endothelial cells are damaged?
Nitrous Oxide (NO)
What are “Lysosomes”?
Digestive enzymes.
What is the cellular effect of ischemia that leads to cell dysfunction and death?
The lack of oxygen restricts the cell’s ability to metabolise ATP within the mitochondria. This causes dysfunction of sodium-potassium pumps which require ATP to function. This leads to cell swelling due to water invasion within the cell. If swelling continues, the cell will burst.
What results from mechanical damage to a cell (i.e., mechanical damage to the cellular membrane)?
When the cell membrane is torn apart, extracellular ions (specifically calcium) invade the cell. This causes the release of enzymes, creating reactive oxygen species of free radicals that can lead to mitochondrial dysfunction.
How do O2 free radicals cause damage within cells?
A free radical is a molecule with an electron removed. As these move around a cell, they rip electrons from other molecules and structures and cause internal damage within the cell.
A) Which version of cell death results in inflammation, and B) why does this not occur with the other form?
A) Necrosis.
B) This does not occur with apoptosis as this includes the use of vesicles which remove the cellular debris and use enzymes to clean the area without inflammation.
What are the cardinal signs of inflammation?
- Swelling
- Heat
- Redness
- Pain
- Loss of function
What are the three main constituents of blood?
- Plasma
- Red blood cells
- White blood cells
What percentage of blood volume is A) plasma, and B) formed elements?
A) 55%
B) 45%
What three constituents of blood volume are categorised as “Formed Elements”
- Platelets
- Leukocytes
- Erythrocytes
what percentage of plasma volume is made from A) protein, B) water, and C) other solutes?
A) 6%
B) 92%
C) 2%
What percentage of blood’s formed elements are made from A) platelets, B) leukocytes, and C) erythrocytes?
A) 3-5%
B) 0.1-0.2%
C) 94-96%
What are the five cell types categorised as leukocytes?
- Neutrophils
- Lymphocytes
- Monocytes
- Eosinophils
- Basophils
What are the two broad categories of leukocytes?
- Lymphocytes
- Innate immunity
What are the three durations of inflammation and what are their periods?
- Acute: the first few hours to several days.
- Subacute: up to 10-14 days.
- Chronic: >2 weeks (3-moths for pain)
What are the three stages of the vascular process in the acute inflammation response?
- Vasoconstriction
- Vasodilation
- Increased permeability
What triggers the “Pain” aspect of inflammation’s cardinal signs?
Sensitisation of nociceptors.
Briefly outline the vascular processes of the acute inflammation response.
- Vasoconstriction occurs to limit immediate bleeding.
- Vasodilation occurs in response to NO release from damaged endothelium
- This floods the site with blood and cellular components resulting in heat and redness of the area.
- This increases blood flow and causes transudate permeation and localised swelling.
- Increased permeability occurs which also coincides with increased stickiness of endothelium and increased permeability specifically to WBC - exudate (this also contributes to swelling).
Briefly outline the cellular processes of the acute inflammation response.
- Neutrophils initially respond to cellular damage in the form of MMP (which indiscriminately breaks down cells within the affected area) and Enzymes (which break down the constituents of the cellular components).
- Macrophages then clean up cellular debris via phagocytosis and are dominant at 24 hours.
- Fibroblasts then begin early repair by laying down collagen.
What are the two main initial products of macrophages?
- MMPs (Matrix Metalloproteinases)
- Enzymes.
What is the other name for Macrophages?
Monocytes.
Define “Suppuration”
The formation and accumulation of dead material.
If this occurs in a contained area, an abscess or pimple is formed.
If this occurs internally, the lymphatic system will reabsorb this.
What are the four possible outcomes of acute inflammation and what conditions determine these?
- Resolution and return to homeostasis.
- If there is slight tissue damage or the removal of the causal agent. - Healing by scarring.
- If there is substantial tissue damage, it occurs in non-regenerative tissue, or there is excessive fibrin exudate. - Formation of an abscess.
- If there is excessive tissue damage (necrosis) and bacterial or fungal inflection. - Chronic inflammation.
- If tissue damage is persistent.
Excessive fibrosis can result in a loss of _________.
Function
Chronic inflammation is classed as _____cellular due to the _________ number and _______ of cells that react and are involved.
A) Hypercellular
B) Increased
C) Type
During chronic inflammation, is there an increase or decrease in Neutrophil activity compared to acute inflammation?
Decreased
During chronic inflammation, is there an increase or decrease in Macrophage activity compared to acute inflammation?
Increased
During chronic inflammation, is there an increase or decrease in T and B Cell activity compared to acute inflammation?
Increased
During chronic inflammation, is there an increase or decrease in Fibroblast activity compared to acute inflammation?
Increased
What is the main action of T Cells in chronic inflammation?
Killer T Cells attack, destroy and ingest agents.
Helper T Cells release chemical mediators to bring other cells into the area.