Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pathological Processes > Session 1 > Flashcards

Session 1 Flashcards

1
Q

Define disease

A

Pathological condition of a body part, organ or system characterised by an identifiable group of signs or symptoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is pathology?

A

The study of suffering (disease and cellular dysfunction)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Cytopathology involves the study of…

A

Disaggregated cells rather than tissues to study disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Histopathology involves the study of…

A

Tissues to study disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Give examples of histologcal procedures (3)

A

Core biopsies
Cancer resection specimens
Excised skin lesions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Give examples of cytological procedures (2)

A

Fine needle aspirates of breast/thyroid/salivary glands

Cervical smears

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Give 2 advantages of histological investigations/procedures over cytological investigations/procedures

A

Often therapeutic as well as diagnostic

Can assess architecture as well as cell atypia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Give 3 advantages of using cytological procedures/investigations over histological procedures/investigations

A

Faster and cheaper
Non-invasive or minimally invasive
Can be used for cells in fluid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

The staging of cancer often follows the TNM system which looks at…

A

Tumour
Nodes
Metastases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is autolysis? How can this affect microscopy of a tissue?

A

Self digestion of a tissue which occurs when the blood supply is cut off

Destroys cell and tissue architecture

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How can autolysis be prevented?

A

By use of fixatives that inactivate tissue enzymes, prevent bacterial growth and harden the tissue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What chemical is typically used in fixation of sample for microscopy? What change in appearance will the tissue show after the fixative is applied?

A

Formalin

Raw meat —> Cooked meat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Tissues that have been fixed are placed into a ________ with holes in it to allow the chemical to penetrate the sample

A

Cassette

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why is it important for the tissue to be hard? What is this process called?

A

Allows the tissue to be cut into very thin slices

Embedding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is commonly used as the hardening agent when a tissue is embedded?

A

Paraffin wax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Outline the process of embedding a tissue

A

Dehydration using alcohol in a vacuum
Alcohol replaced with xylene as it can mix with wax
Xylene replaced with molten paraffin wax

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Tissues are typically cut to what thickness? Using which piece of equipment?

A

~3-4 microns

Microtome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What stain is most commonly used to stain samples?

A

H & E stain

Haematoxylin + Eosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What does haematoxylin stain the most?

A

The nucleus most strongly blue

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What does eosin stain the most?

A

The EM (cytoplasm and connective tissue) most strongly pink

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the purpose of mounting a slice of tissue?

A

Preserves and protects the sample

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What does immunohistochemistry involve?

A

Demonstrates substances in/on cells by labelling them with specific antibodies. These antibodies are usually linked to an enzyme that catalyses a colour-producing reaction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are cytokeratins? What is the clinical significance of these?

A

Family of intracellular fibrous proteins present in epithelial cells

They are markers for epithelial differentiation and show a tissue specific distribution in epithelia. So they can be used to show whether a cancer is a carcinoma and its primary site depending on the combination of different cytokeratins found

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Why are frozen sections sometimes taken?

A

It’s a method of hardening tissue quickly - useful intra-operatively as it gives a quick result and can influence the course of the operation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Why are frozen sections not routinely used?

A

They provide a lower quality sample - cell morphology is not as good as in paraffin sections

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What piece of equipment is used to take frozen sections?

A

A cryostat (microtome inside a freezer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is hypoxia?

A

Decreased oxygen supply to certain cells/tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is ischaemia?

A

Decreased blood supply to certain cells/tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Why is ischaemia worse than hypoxia?

A

In ischaemia other nutrients such as glucose are also not supplied to cells/tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Name 4 types of hypoxia

A

Hypoxaemic hypoxia
Anaemia hypoxia
Ischaemic hypoxia
Histiocytic hypoxia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is hypoxaemic hypoxia? Give an example of a cause

A

Where the arterial content of oxygen is low - e.g. There is reduced absorption of oxygen in the lungs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is anaemic hypoxia? Give an example of a cause

A

Where there is decreased ability of haemoglobin to carry oxygen (e.g. In anaemia)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is ischaemic hypoxia? Give an example of a cause

A

Where there is interruption to blood supply (e.g. There is blockage of a vessel)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is histiocytic hypoxia? Give an example of a cause

A

The inability to utilise the oxygen within cells (e.g. Damaged oxidative phosphorylation enzymes due to cyanide poisoning)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

The effects of hypoxia depends on…

A

Which cells/tissues it is affecting, some cells are damaged more quickly by hypoxia

E.g. Neurones last a few minutes, Fibroblasts last a few hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are hypersensitivity reactions?

A

Where the host tissue is injured secondary to an overly vigorous immune reaction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What are autoimmune reactions?

A

Immune system fails to distinguish self from non-self

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are free radicals?

A

Reactive oxygen species that have a single unpaired electron in its outer orbit making it unstable and more reactive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are 3 significant free radicals? Which is the most dangerous?

A

OH* (hydroxyl)
O2- (superoxide)
H2O2 (hydrogen peroxide)

Hydroxyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

How are free radicals produced? (5)

A

Normal metabolic reactions - e.g. Oxidative phosphorylation

Inflammation - oxidative burst of neutrophils is used to kill microorganisms

Radiation - converts water to hydroxyl

Contact with unbound metals within the body (e.g. Fe/Cu)

Drugs (e.g. Metabolism of paracetamol in the liver)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Haemachromatosis is caused by…

A

Excess of iron

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Wilson’s disease is caused by…

A

Excess of copper

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What controls do we have against free radicals? (3)

A

Anti-oxidant system

Metal carrier and storage proteins

Enzymes that neutralise free radicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What does the anti-oxidant system consist of? How does it work against free radicals?

A

Vitamins A, C & E

They donate electrons to the free radical

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Give an example of a metal carrier protein that sequesters…

(I) iron
(II) copper

A

Transferrin

Ceruloplasmin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Give 3 examples of enzymes that neutralise free radicals.

A

Superoxide dismutase
Catalase
Glutathione peroxidase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

How do free radicals injure cells?

A

They injure cell membranes and cause lipid peroxidation and then further free radicals

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is oxidative imbalance?

A

Where the number of free radicals overwhelms the anti-oxidant system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

As well as lipids, which other cell structures can be oxidised by free radicals? What are the consequences of this?

A

Proteins, carbohydrates, DNA

Causes mutations in DNA and can therefore be carcinogenic, also bends proteins out of shape

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is the function of heat shock proteins?

A

During any cell injury, these proteins stop producing their usual products and aim to mend mis-folded proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is karyolysis?

A

Nuclear fading - dissolution of chromatin due to action of DNAases and RNAases leading to cell death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is pyknosis?

A

Nuclear shrinkage - DNA condenses into shrunken basophilic mass leading to cell death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What is karyorrhexis?

A

Nuclear fragmentation - nuclear membrane ruptures and nucleus undergoes fragmentation leading to cell death

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

How will injured cells appear under the microscope?

A

Often pale and swollen due to poorer function of the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Hypoxia can result in cytoplasmic changes, nuclear changes and abnormal cellular accumulations seen under the microscope what is an example of these abnormal accumulations?

A

Fat in hepatocytes

56
Q

What is an example of a reversible change that can be seen in an injured cell under an electron microscope?

A

Blebbing because the cytoskeleton is being broken down by proteases

57
Q

How can cell death be diagnosed?

A

Cells placed in fluid with a dye - dead cells with non-functioning membranes will take up the dye

58
Q

What is oncosis?

A

Cell death with swelling, the spectrum of changes that occur in injured cells prior to death

59
Q

What is necrosis?

A

In a living organism, the morphological changes that occur after a cell has been dead some time (after 12-24 hours)

60
Q

Name 4 types of necrosis

A

Coagulative
Liquefactive
Caseous
Fat

61
Q

Coagulative necrosis takes place in which sorts of tissues?

A

Solid organs with a lot of connective tissue support e.g. Kidneys

62
Q

Liquefactive necrosis takes place in which sorts of tissues?

A

Loose tissues e.g. Brain

63
Q

What happens in coagulative necrosis?

A

Denaturation of proteins dominates over the release of active proteases

64
Q

How does coagulative necrosis look under the microscope?

A

The cellular architecture is somewhat preserved with the ‘ghost outline’ of cells

65
Q

What happens in liquefactive necrosis? How does it appear under the microscope?

A

Enzyme degradation is substantially grater than denaturation and there is enzymatic degradation of tissues

resulting in no cell architecture being seen under the microscope

66
Q

What is caseous necrosis? In what cases is it most common?

A

Contains amorphous (structureless) debris - ‘cottage cheese’ appearance

In infections - especially TB

67
Q

What type of necrosis is particularly associated with infections such as TB?

A

Caseous necrosis

68
Q

Give two examples of where fat necrosis can be seen?

A

In pancreatitis

In the breast

69
Q

What happens in pancreatitis with regards to fat necrosis?

A

Digestive enzymes leak out into the abdominal cavity and break down lipids into fatty acids. Fatty acids react with calcium to form calcium soaps which are then deposited.

70
Q

What happens in the breast with regards to fat necrosis?

A

There is disruption of fat in the breast and a hard lump forms in the breast

71
Q

What is gangrene?

A

Necrosis visible to the naked eye

72
Q

What is dry gangrene?

A

Visible necrosis modified by exposure to air - commonly coagulative necrosis

73
Q

What is wet gangrene?

A

Visible necrosis modified by infection - commonly liquefactive necrosis

74
Q

What is gas gangrene?

A

Wet gangrene where the infection is with anaerobic bacteria that produce gas

75
Q

What is an infarction?

A

Necrosis caused by reduction in arterial blood flow

76
Q

What is an infarct?

A

An area of necrotic tissue which is the result of loss of arterial blood supply

77
Q

Name two common causes of infarction

A

Thrombosis

Embolism

78
Q

Infarcted tissue can appear which two colours?

A

White or red

79
Q

Where are white infarcts most common? What causes them? What is the reason for their appearance? What type of necrosis is commonly associated with white infarcts?

A

Solid organs e.g. Kidneys

There is usually occlusion of an end artery with no collateral blood supply

There is no blood haemorrhage into the area giving a white appearance

Coagulative

80
Q

Where do red infarcts commonly take place? What is the reason for their red appearance?

A

Loose tissues e.g. Lungs
There is haemorrhage into necrotic areas. There is often a dual blood supply with not enough blood to rescue the area but blood still pumping.

81
Q

What is ischaemia-reperfusion injury?

A

Worse damage that results from reperfusing ischaemic tissues. Results in…

Increased production of oxygen free radicals
Increased number of neutrophils and more inflammation
Activation of the complement pathway

82
Q

Leaky membranes can cause molecules to leak out of cells as well as in. What can leak out? What effect can each molecule have?

A

Potassium
Enzymes
Myoglobin

83
Q

What can too much calcium outside a cell result in?

A

Cardiac arrest

84
Q

Myoglobin can leak out of damaged skeletal muscle cells in response to…

What can it result in? (2)

A

Trauma/Extreme Exercise

Brown urine and renal failure

85
Q

What is apoptosis?

A

Cell death with shrinkage

86
Q

Does apoptosis require ATP?

A

Yes

87
Q

How does apoptosis work?

A

Activates enzymes that degrade its own nuclear DNA and proteins

88
Q

How is DNA broken down in apoptosis? How is DNA broken down in oncosis?

A

Inter-nucleosomal cleavage of dna

Random cleavage of DNA

89
Q

How is membrane integrity affected in apoptosis? Are lysosomal enzymes involved in apoptosis? How fast is the process of apoptosis?

A

Membrane integrity is maintained

No

Quick - few hours

90
Q

Give 3 physiological examples of apoptosis in the human body.

A

To maintain a steady number of cells

To reduce the size of ovaries after removal of oestrogen in post menopausal women

Apoptosis between the digits on a human hand

91
Q

Give 3 examples of pathological apoptosis in the human body.

A

Cytotoxic T cell killing of virus infected or neoplastic cells

Damaged cells with damaged DNA

Graft versus host disease

92
Q

What are the 3 phases of apoptosis?

A

Initiation
Execution
Degradation & Phagocytosis

93
Q

Apoptosis can be activated via ___________ or ___________ pathways. Both pathways result in the activation of ___________

A

Extrinsic or intrinsic

Caspases

94
Q

What are caspases?

A

Enzymes that control and mediate apoptosis, cause the cleavage of DNA + proteins

95
Q

What is meant by the intrinsic pathway of apoptosis? What typically triggers it?

A

Everything happens within the cell

Irreparable DNA damage

96
Q

What happens in the intrinsic pathway of apoptosis?

A

P53 protein is activated —-> Outer mitochondrial membrane becomes leaky —-> Cytochrome C is released from the mitochondria —-> Activation of caspases

97
Q

What is meant by the extrinsic pathway of apoptosis? What typically triggers it?

A

Initiated by extracellular signals

Cells that are a danger e.g. Tumour cells/virus infected cells

98
Q

What happens in the extrinsic pathway of apoptosis?

A

E.g. TNFalpha secreted by t killer cells in response to cells that are a danger —-> Bind to cell membrane death receptor (death receptor) —-> Activation of caspases

99
Q

What happens to the apoptotic bodies produced in the intrinsic/extrinsic pathways?

A

They express proteins on their surface that allow them to be recognised, phagocytosed and degraded by phagocytes or neighbouring cells

100
Q

Why does cellular accumulation occur?

A

As a result of a cell not being able to metabolise something

101
Q

What is meant by the term hydropic swelling?

A

Accumulation of fluid

102
Q

When does fluid accumulation occur?

A

When energy supplies are cut off - e.g. In hypoxia

103
Q

What happens in fluid accumulation?

A

Na+ and water flood into the cell

104
Q

Why is cerebral oedema a particular problem?

A

Increased pressure on the skull, structures in the brain/spinal cord get compressed - blood supply may be compromised

105
Q

What is steatosis? Where is it commonly seen and why?

A

The accumulation of triglycerides in a cell

The liver as it is a major organ of fat metabolism

106
Q

What are some common causes of steatosis?

A

Alcohol
Diabetes
Obesity

107
Q

Cholesterol can only be eliminated through the _______

A

Liver

108
Q

Is cholesterol soluble or insoluble?

A

Insoluble

109
Q

How is excess cholesterol stored?

A

In cells within vesicles

110
Q

In particular what two types of cells can cholesterol accumulate in?

A

Smooth muscle cells and macrophages

Produces foam cells

111
Q

How do accumulated proteins appear under the microscope?

A

As eosinophilic droplets in the cytoplasm

112
Q

What protein accumulations are seen in alcoholic liver disease?

A

Mallory’ hyaline - accumulation of damaged keratin filaments

113
Q

What causes alpha1-antitrypsin deficiency? What can it result in?

A

Incorrectly folded a1-antitrypsin proteins - accumulates in ER and leads to deficiencies as a result

Can lead to emphysema as proteases act unchecked in the lungs

114
Q

What are some examples of exogenous pigments that can accumulate in the body?

A

Air pollutants such as carbon, coal dust, soot

115
Q

What happens to pigments such as soot that are inhaled?

A

They are phagocytosed by alveolar macrophages resulting in anthracosis (blackening of the lungs) and blackened peribronchial lymph nodes

116
Q

Small amounts of pigment accumulation is usually harmless. Large amounts can result in…

A

Fibrosis and emphysema (coal worker’s pneumoconiosis)

117
Q

What happens to some of the pigment following a tattoo…

A

Some reaches and stays in the draining lymph nodes

118
Q

What is haemosiderin?

A

An endogenous pigment and iron storage molecule derived from haemoglobin

119
Q

What colour does haemosiderin have?

A

Yellow/brown colour

120
Q

When does haemosiderin form?

A

When there is a systemic or local excess of iron

121
Q

What happens when there is a systemic excess of iron?

A

Haemosiderosis - it is deposited in organs

122
Q

What can cause haemosiderosis? (3)

A

Haemolytic anaemia, blood transfusions and hereditary haemochromatosis

123
Q

What is the result of hereditary haemochromatosis?

A

Increased intestinal absorption of dietary iron and deposition of iron in organs (haemosiderosis).

124
Q

What are some symptoms of hereditary haemochromatosis?

A

Liver damage, heart dysfunction and endocrine failures

125
Q

What is the treatment for hereditary haemochromatosis?

A

Repeated bleeding?

126
Q

Jaundice is as a result of the accumulation of…

What colour does it have?

A

Bilirubin

Bright yellow

127
Q

How is bilirubin formed? In which cells of the body?

A

As a breakdown product of heme

All cells of the body

128
Q

How is bile excreted?

A

Taken from tissues bound to albumin to the liver and excreted in the bile

129
Q

When does jaundice occur?

A

When bile flow is obstructed or overwhelmed

130
Q

Where is bilirubin deposited in jaundice?

A

Extracellularly or in macrophages

131
Q

What is meant by the calcification of tissues?

A

Abnormal deposition of calcium salts within tissues

132
Q

Calcification of tissues can either be localised (___________) or generalised (__________)

A

Dystrophic

Metastatic

133
Q

Is dystrophic calcification more or less common than metastatic calcification? When does it occur? (5)

A

More common

In areas of dying tissue, atherosclerotic plaques, ageing or damaged heart valves, TB lymph nodes, malignancies

134
Q

What happens in metastatic calcification?

A

Hypercalcaemia in the blood as a result of abnormal calcium metabolism results in calcium hydroxyapatite crystals being deposited in normal tissues throughout the body

135
Q

What are two main causes of hypercalcaemia?

A

Increased secretion of parathyroid hormone (PTH) resulting in bone resorption (can be primary, secondary or ectopic)

Destruction of bone tissue

136
Q

After a certain number of divisions cells reach ____________ _____________ where they can no longer divide. This is related to the length of their ___________.

A

Replicative senescence

Telomeres

137
Q

What is the function of telomerase? Which types of cells produce telomerase?

A

Maintains the length of telomeres so cells can continue to replicate

Germ cells, stem cells and cancer cells

Pathological Processes (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions