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MCRP: Clinical Sciences > Molecular Medicine > Flashcards

Molecular Medicine Flashcards

1
Q

What are the phases of the cell cycle?

A

G0: Resting phase
G1: Gap 1 - cell increase in size
S: Synthesis of DNA, RNA, Histome and centromere duplication
G2: Gap 2 - cells continue to increase in size
Mitosis
G0

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2
Q

What phase of the cell cycle determine the length of the cell cycle?

A

Gap 1

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3
Q

What governs G1 phase?

A

p53

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4
Q

What regulatory proteins govern transition from G1 to S phase the cell cycle?

A

Cyclin D / CDK4
Cyclin D / CDK6
Cyclin E / CDK2:

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5
Q

What regulatory protein governs synthesis phase?

A

Cyclin A / CDK2: active in S phase

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6
Q

What regulatory protein governs transition from G2 to m phase?

A

Cyclin B / CDK1: regulates transition from G2 to M phase

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7
Q

What is the shortest phase of the cell cycle?

A

Mitosis

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8
Q

What are the features of mitosis?

A

Somatic cells
Genetically identical to parent cell
Results in 2 diploid daughter cells

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9
Q

What are the features of meiosis?

A

Gamete cells
Contain one homologue - genetically different
4 haploid cells

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10
Q

What are the phases of mitosis?

A

Interphase: G0, S phase and G2

Mitosis: M phase
Prometaphase
Metaphase
Anaphase
Telophase
Cytokinesis

G0

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11
Q

What occurs in prometaphase?

A

Nuclear membrane breaks down allowing the microtubules to attach to the chromosomes

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12
Q

What occurs in metaphase?

A

Chromosomes aligned at middle of cell

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13
Q

What occurs in anaphase?

A

The paired chromosomes separate at the kinetochores and move to opposite sides of the cell

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14
Q

What occurs in telophase?

A

Chromatids arrive at opposite poles of cell

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15
Q

What occurs in cytokinesis?

A

Actin-myosin complex in the centre of the cell contacts resulting in it being ‘pinched’ into two daughter cells

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16
Q

What is the CD of haematopietic stem cells?

A

CD34

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17
Q

What is the CD of T helper cells?

A

CD4, TCR, CD3, CD28

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18
Q

What is the CD of cytotoxic T cells?

A

CD8, TCR, CD3, CD28

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19
Q

What is the CD of regulatory T cells?

A

CD4, CD25, TCR, CD3, CD28

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20
Q

What are the CD of B cells?

A

CD19, CD20, CD40, MHC II, B7

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21
Q

What are the CD of macrophages?

A

CD14, CD40, MHC II, B7

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22
Q

What are the CD of NK cells?

A

CD16, CD56

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23
Q

What is the function of CD 1?

A

This is the MHC MHC molecule that presents lipid molecules

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24
Q

What is the function of CD 2?

A

Found on thymocytes, T cells, and some natural killer cells that acts as a ligand for CD58 and CD59 and is involved in signal transduction and cell adhesion

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25
Q

What is the function of CD 3?

A

The signalling component of the T cell receptor (TCR) complex

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26
Q

What is the function of CD 4 ?

A

Found on helper T cells.
Co-receptor for MHC class II
Used by HIV to enter T cells

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27
Q

What is notable about CD 5 ?

A

Found in the majority of mantle cell lymphomas

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28
Q

What is CD8?

A

Found on cytotoxic T cells.
Co-receptor for MHC class I
Found on a subset of myeloid dendritic cells

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29
Q

What is the cell surface rector for macrophages?

A

CD 14

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30
Q

What CDs are expressed on reed steinberg cells?

A

CD 15 and CD 30

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31
Q

What is the function of CD 16?

A

Bind to the Fc portion of IgG antibodies

Fc component is the antibody class component

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32
Q

What is CD 21 located on ?

A

EBV

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33
Q

What is the function of Cd 95?

A

Acts as the FAS receptor, involved in apoptosis

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34
Q

What is the function of CD 56?

A

Unique marker for natural killer cells

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35
Q

What is the function of the rough endoplasmic reticulum?

A

Translation and folding of new proteins
manufacture of lysosomal enzymes
site of N-linked glycosylation

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36
Q

What cells typically have large rough endoplasmic reticulum?

A

Extensive RER include pancreatic cells, goblet cells, plasma cells

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37
Q

What is the function of the smooth endoplasmic reticulum?

A

Steroid, lipid synthesis

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38
Q

What cells have large smooth endoplasmic reticulum?

A

extensive SER include those of the adrenal cortex, hepatocytes, testes, ovaries

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39
Q

What is the function of Golgi apparatus?

A

Modifies, sorts, and packages these molecules that are destined for cell secretion

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40
Q

What is the function of mitochondria?

A

Aerobic respiration. Contains mitochondrial genome as circular DNA

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41
Q

What occurs in the nucleus?

A

DNA maintenance
RNA transcription
RNA splicing

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42
Q

What is the function of the nucleolus?

A

Ribosome production

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43
Q

What is the function of the function of a ribosome?

A

Translation

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44
Q

What is the function of the proteasome?

A

Along with the lysosome pathway involved in degradation of protein molecules that have been tagged with ubiquitin

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45
Q

What is the function of complement proteins?

A

Circulating plasma proteins involved in inflammatory and immune reaction of the body.
Complement proteins are involved in chemotaxis, cell lysis and opsonisation

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46
Q

What disease is associated with deficiency of C1 inhibitor deficiency?

A

Hereditary angiodema

Probable mechanism is uncontrolled release of bradykinin resulting in oedema of tissues

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47
Q

What disease is associated with classical pathway complement protein deficiency?

A

Immune complex diseases
HSP and SLE

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48
Q

What are the complement proteins in the classical pathway?

A

C1q, C1rs, C2, C4 deficiency (classical pathway components)

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49
Q

What is associated with a C3 deficiency?

A

Bacterial infections

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50
Q

What is associated with C5 deficiency?

A

Leiner disease
- recurrent diarrhoea, wasting and seborrhoeic dermatitis

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51
Q

What is associated with C5-C9 deficiency?

A

encodes the membrane attack complex (MAC)
particularly prone to Neisseria meningitidis infectio

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52
Q

What complement proteins encode MAC?

A

C5-C9

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53
Q

What is the function of IL-1?

A

Produced by macrophages

Induces fever
Acute inflammation

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54
Q

What is the function of IL-2?

A

Produced by Th-1 cells

Stimulates growth and differentiation of T cell response

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55
Q

What is the function of IL-3?

A

Produced by activated T helper cells

Stimulates differentiation and proliferation of myeloid progenitor cells

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56
Q

What is the function of IL-4?

A

Produced by Th2 cells

Stimulates proliferation and differentiation of B cells

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57
Q

What is the function of Il-5?

A

Produced by Th2 cells

Stimulate production of eosinophils

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58
Q

What is the function of IL -6?

A

Produced by Macrophages, Th2 cells

Stimulates differentiation of B cells
Induces fever

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59
Q

What is the function of IL - 8?

A

” Eight - brings a mate”

Produced by Macrophages

Neutrophil chemotaxis

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60
Q

What is the function of IL - 10?

A

Produced by Th2 cells

Inhibits Th1 cytokine production
Also known as human cytokine synthesis inhibitory factor and is an ‘anti-inflammatory’ cytokine

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61
Q

What is the function of IL -12?

A

Dendritic cells, macrophages, B cells

Activates NK cells and stimulates differentiation of naive T cells into Th1 cells

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62
Q

Function of TNF alpha?

A

Produced by macrophages

Induces fever
Neutrophil chemotaxis

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63
Q

What is the function of Interferon-γ?

A

Activates macrophages

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64
Q

What is the function of endothelin?

A

potent, long-acting vasoconstrictor and bronchoconstrictor
Thought to be behind primary pulmonary hypertension (endothelin antagonists are now used), cardiac failure, hepatorenal syndrome and Raynaud’s.

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65
Q

What is the mechanism by which endothelin works? What promotes release and inhibits release?

A

G-protein linked to phospholipase C leading to calcium release

Promotes release: angiotensin II, ADH, hypoxia, mechanical shearing forces

Inhibits release: Nitric oxide. prostacyclin

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66
Q

What diseases are associated with HLA-A3?

A

Haemochromatosis

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67
Q

What encodes the HLA antigen?

A

Chromosome 6
A,B,C - class one antigens
DP, DQ, DR - class two antigens

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68
Q

What diseases are associated with HLA-B51?

A

Behçet’s disease

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69
Q

What diseases are associated with HLA-B27?

A

ankylosing spondylitis
reactive arthritis
acute anterior uveitis
Ulcerative colitis

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70
Q

What diseases are associated with HLA-DQ2 or HLA-DA8?

A

Coeliac disease

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71
Q

What disease are associated with HLA-DR2?

A

narcolepsy
Goodpasture’s

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72
Q

What disease are associated with HLA-DR3?

A

dermatitis herpetiformis
Sjogren’s syndrome
primary biliary cirrhosis

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73
Q

What disease are associated with HLA-DR4?

A

type 1 diabetes mellitus*
rheumatoid arthritis - in particular the DRB1 gene (DRB104:01 and DRB104:04 hence the association with DR4)

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74
Q

What is the mechanism of type 1 hypersensitivity reaction?

A

Antigen reacts with IgE bound to mast cells

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75
Q

What is the mechanism of type 2 hypersensitivity reaction?

A

IgG or IgM binds to antigen on cell surface

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76
Q

What is the mechanism of type 3 hypersensitivity reaction?

A

Free antigen and antibody (IgG, IgA) combine

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77
Q

What is the mechanism of type 4 hypersensitivity reaction?

A

Cell mediated - T cell

78
Q

What is the mechanism of type 5 hypersensitivity reaction?

A

Antibodies that recognise and bind to the cell surface receptors.

This either stimulating them or blocking ligand binding

79
Q

What are example of type 2 hypersensitivity reaction?

A

Autoimmune haemolytic anaemia
* ITP
* Goodpasture’s syndrome
* Pernicious anaemia
* Acute haemolytic transfusion reactions
* Rheumatic fever
* Pemphigus vulgaris / bullous pemphigoid

80
Q

What are example of type 3 hypersensitivity reaction?

A
  • Serum sickness
  • Systemic lupus erythematosus
  • Post-streptococcal glomerulonephritis
  • Extrinsic allergic alveolitis (especially acute phase)
81
Q

What are examples of type 4 hypersensitivity reactions?

A
  • Tuberculosis / tuberculin skin reaction
  • Graft versus host disease
  • Allergic contact dermatitis
  • Scabies
  • Extrinsic allergic alveolitis (especially chronic phase)
  • Multiple sclerosis
  • Guillain-Barre syndrome
82
Q

What are examples of type 5 hypersensitivity reaction?

A
  • Graves’ disease
  • Myasthenia gravis
83
Q

What is the function of neutrophils?

A

Innate immune system
Primary phagocytic cell in acute inflammation
Granules contain myeloperoxidase and lysozyme
Most common type of white blood cell
Multi-lobed nucleus

84
Q

What is the function of basophils?

A

Innate immune system
Releases histamine during allergic response
Granules contain histamine and heparin
Expresses IgE receptors on the cell surface
Bi-lobed nucleus

85
Q

What is the function of mast cells ?

A

Innate immune system
Present in tissues and are similar in function to basophils but derived from different cell lines
Releases histamine during allergic response
Granules contain histamine and heparin
Expresses IgE receptors on the cell surface

86
Q

What is the function of eosinophils?

A

Innate immune system
Defends against protozoan and helminthic infections
Bi-lobed nucleus

87
Q

What is the function of monocytes?

A

Innate immune system
Diffferentiates into macrophages
Kidney shaped nucleus

88
Q

What is the function of macrophages?

A

Innate immune system
Involved in phagocytosis of cellular debris and pathogens
Acts as an antigen presenting cell
Major source of IL-1

89
Q

What is the function of NK cells?

A

Innate immune system
Induce apoptosis in virally infected and tumour cells

90
Q

What is the function of dendritic cells?

A

Acts as an antigen presenting cell

91
Q

What is the function of helper T cells?

A

Adaptive immune system
Involved in the cell-mediated immune response
Recognises antigens presented by MHC class II molecules
Expresses CD4
Also expresses CD3, TCR & CD28
Major source of IL-2
Mediates acute and chronic organ rejection

92
Q

What is the function of cytotoxic T cells?

A

Adaptive immune system
Involved in the cell-mediated immune response
Recognises antigens presented by MHC class I molecules
Induce apoptosis in virally infected and tumour cells
Expresses CD8
Also expresses CD3, TCR
Mediates acute and chronic organ rejectio

93
Q

What is the function of B cells?

A

Adaptive immune system
Major cell of the humoral immune response
Acts as an antigen presenting cell
Mediates hyperacute organ rejection

94
Q

What is the function of plasma cells?

A

Adaptive immune system
Differentiated from B cells
Produces large amounts of antibody specific to a particular antigen

95
Q

What is the function IgG?

A
  • Enhance phagocytosis of bacteria and viruses
  • Fixes complement and passes to the fetal circulation
  • Most abundant isotype in blood serum
96
Q

What is the function if IgA ?

A
  • IgA is the predominant immunoglobulin found in breast milk. It is also found in the secretions of digestive, respiratory and urogenital tracts and systems
  • Provides localized protection on mucous membranes
  • Most commonly produced immunoglobulin in the body (but blood serum concentrations lower than IgG
    .)
  • Transported across the interior of the cell via transcytosis
97
Q

What shape is IgA?

A

Monomer or dimer

98
Q

What shape if IgM?

99
Q

What is the function of IgM?

A
  • First immunoglobulins to be secreted in response to an infection
  • Fixes complement but does not pass to the fetal circulation
  • Anti-A, B blood antibodies (note how they cannot pass to the fetal circulation, which could of course result in haemolysis)
100
Q

What is the function of IgD?

A
  • Role in immune system largely unknown
  • Involved in activation of B cells
101
Q

What is the function of IgE?

A
  • Mediates type 1 hypersensitivity reactions
  • Synthesised by plasma cells
  • Binds to Fc receptors found on the surface of mast cells and basophils
  • Provides immunity to parasites such as helminths
  • Least abundant isotype in blood serum
102
Q

What is interferon?

A

Interferons (IFN) are cytokines released by the body in response to viral infections and neoplasia. They are classified according to cellular origin and the type of receptor they bind to.

103
Q

What type of receptors do IFN alpha and beta bind to ?

A

Type 1 receptors

104
Q

What type of receptors do IFN gamma bind to ?

A

Type 2 receptors

105
Q

What is the function if IFN alpha?

A

Produced by leucocytes
Antiviral action
Useful in hepatitis B & C, Kaposi’s sarcoma, metastatic renal cell cancer, hairy cell leukaemia
Adverse effects include flu-like symptoms and depression

106
Q

What is the function of IFN beta?

A

Produced by fibroblasts
Antiviral action
Reduces the frequency of exacerbations in patients with relapsing-remitting MS

107
Q

What is the function of IFN gamma?

A

predominately natural killer cells. Also by T helper cells
weaker antiviral action, more of a role in immunomodulation particularly macrophage activation
may be useful in chronic granulomatous disease and osteopetrosis

108
Q

How is iron absorbed in the body?

A

Upper small intestine especially the duodenum
about 10% of dietary iron absorbed
Fe2+ (ferrous iron) much better absorbed than Fe3+ (ferric iron)

109
Q

What increases and decreases amount of iron absorbed?

A

Increased: Vitamin C, gastric acid
Decreased: Proton pump inhibitors, tetracycline, gastric achlorhydria, tannin (found in tea)

110
Q

How is iron dstirbuted in the body?

A

Total body iron = 4g

haemoglobin = 70%
ferritin and haemosiderin = 25%
myoglobin = 4%
plasma iron = 0.1%

111
Q

How is iron transported and stored in the body ?

A

carried in plasma as Fe3+ bound to transferrin
stored as ferritin in tissues
lost via intestinal tract following desquamation

112
Q

What is the function of leukotrines?

A

mediators of inflammation and allergic reactions
cause bronchoconstriction, mucous production
increase vascular permeability, attract leukocytes
leukotriene D4 has been identified as the SRS-A (slow reacting substance of anaphylaxis)

113
Q

How are leukotrines formed?

A

Arachidonic acid metabolism
formed from arachidonic acid by action of lipoxygenase

114
Q

Why is it thought asthmatic react to NSAIDS?

A

NSAID induced bronchospasm in asthmatics is secondary to the express production of leukotrienes due to the inhibition of prostaglandin synthetase

115
Q

At what speed does Ligand-gated ion channel receptors work?

116
Q

What are examples of ligand-gate ion channels?

A

Nicotinic acetylcholine
GABA-A
GABA-C
Glutamate receptors

117
Q

What are examples of tyrosine kinase receptors?

A

Insulin, insulin-like growth factor (IGF), epidermal growth factor (EGF)

118
Q

What are examples of guanylate cyclase receptors?

A

contain intrinsic enzyme activity
Atrial natriuretic factor
Brain natriuretic peptide

119
Q

How does as G protein couple receptor work, and typically what processes does it affect?
What are the three types of G protein?

A

Generally mediate slow transmission and affect metabolic processes
Gs, Gi and Gq

120
Q

What is the mechanism of action of Gs protein coupled receptors?

A

Stimulates adenylate cyclase → increases cAMP → activates protein kinase A

121
Q

What is the mechanism of Gi protein coupled receptors?

A

Inhibits adenylate cyclase → decreases cAMP → inhibits protein kinase A

122
Q

What is the mechanism of Gq protein coupled receptors?

A

Activates phospholipase C → splits PIP2 to IP3 & DAG → activates protein kinase C

123
Q

What type of receptor is B1 receptor? Example of receptor?

A

GS protein
Beta-1 receptors
- epinephrine
- norepinephrine
- dobutamine)

124
Q

Example of GS protein coupled receptors?

A

B1 receptor
Beta-2 receptors (epinephrine, salbuterol)
H2 receptors (histamine)
D1 receptors (dopamine)
V2 receptors (vasopressin)
Receptors for ACTH, LH, FSH, glucagon, PTH, calcitonin, prostaglandins

125
Q

Example of Gi protein coupled receptor?

A
  • M2 receptors (acetylcholine)
  • Alpha-2 receptors (epinephrine, norephinephrine)
  • D2 receptors (dopamine)
  • GABA-B receptor
126
Q

Examples of Gq protein coupled receptors?

A
  • Alpha-1 receptors (epinephrine, norepinephrine)
  • H1 receptors (histamine)
  • V1 receptors (vasopressin)
  • M1, M3 receptors (acetylcholine)
127
Q

Examples of non-receptor tyrosine kinases?

A

PIGG(L)ET: Prolactin, Immunomodulators (cytokines IL-2, Il-6, IFN), GH, G-CSF, Erythropoietin and Thromobopoietin

128
Q

What direction does dynein move on a microtubule?

A

dynein moves in a retrograde fashion, down the the microtubule towards the centre of the cell (+ve → -ve)

129
Q

What direction does kinesin move on a microtubule?

A

kinesin moves in an anterograde fashion, up the microtubule away from the centre, towards the periphery (-ve → +ve)

130
Q

What does southern blotting detect?

131
Q

What does northern blotting detect?

132
Q

What does western blotting detect?

133
Q

How does an ELISA work?

A

Type of biochemical assay used to detect antigens and antibodies
a colour changing enzyme is attached to the antibody if looking for an antigen and to an antigen if looking for an antibody
the sample therefore changes colour if the antigen or antibody is detected

134
Q

What is the action of leptin in obesity?

A

Leptin on satiety centres in the hypothalamus and decreases appetite. More adipose tissue (e.g. in obesity) results in high leptin levels.

Leptin stimulates the release of melanocyte-stimulating hormone (MSH) and corticotrophin-releasing hormone (CRH). Low levels of leptin stimulates the release of neuropeptide Y (NPY)

135
Q

What is the action of leptin in obesity?

A

Leptin on satiety centres in the hypothalamus and decreases appetite. More adipose tissue (e.g. in obesity) results in high leptin levels.

Leptin stimulates the release of melanocyte-stimulating hormone (MSH) and corticotrophin-releasing hormone (CRH). Low levels of leptin stimulates the release of neuropeptide Y (NPY)

136
Q

What is the action of ghrelin in obesity?

A

Ghrelin induces hunger

137
Q

What are onocogenes?

A

Derived from protooncogenes (normal genes for cell growth and differentiation)
A ‘gain of function’ results in an increased risk of cancer.
Only one mutated copy of the gene is needed for cancer to occur - a dominant effect.

138
Q

What are onocogenes?

A

Derived from protooncogenes (normal genes for cell growth and differentiation)
A ‘gain of function’ results in an increased risk of cancer.
Only one mutated copy of the gene is needed for cancer to occur - a dominant effect.

139
Q

What cancer is associated with the oncogenes ABL?

140
Q

What cancer is associated with the oncogenes c-MYC?

A

Burkitt’s lymphoma

141
Q

What cancer is associated with the oncogenes n-myc?

A

Neuroblastoma

142
Q

What cancer is associated with the oncogenes BCL2?

A

Follicular lymphoma

143
Q

What cancer is associated with the oncogenes RET?

A

Multiple endocrine neoplasia type 1 and type 2

144
Q

What cancer is associated with the oncogenes RAS?

A

Pancreatic and others

145
Q

How do tumour suppressor and oncogenes mutations differ?

A

Tumor suppressor genes - loss of function results in an increased risk of cancer

Oncogenes - gain of function results in an increased risk of cancer

146
Q

What cancers are associated with EBV?

A

Burkitt’s lymphoma
Hodgkin’s lymphoma
Post transplant lymphoma
Nasopharyngeal carcinoma

147
Q

What cancers are associated with HPV 16/18?

A

Cervical cancer
Anal cancer
Penile cancer
Vulval cancer
Oropharyngeal cancer

148
Q

What cancers are associated with human heperes 8 virus?

A

Kaposi sarcoma

149
Q

What cancers are associated with Hep B and Hep C?

A

Hepatocellular carcinoma

150
Q

What cancers are associated with human T lymphoctyic virus?

A

Tropical spastic paraparesis
Adult T cell leukaemia

151
Q

Where is p53 located?

A

Chromosome 17 p ( short)

152
Q

What is the function of p53?

A

cell cycle, preventing entry into the S phase until DNA has been checked and repaired. It may also be a key regulator of apoptosis

153
Q

What genetic disease is associated with p53 mutation?

A

Li-Fraumeni syndrome is a rare autosomal dominant disorder characterised by the early onset of a variety of cancers such as sarcoma, breast cancer and leukaemias. It is caused by mutation in the p53 gene.

154
Q

What is penetrance?

A

enetrance describes the proportion of a population of individuals who carry a disease-causing allele who express the related disease phenotype

155
Q

What is expressivity?

A

Expressivity describes the extent to which a genotype shows its phenotypic expression in an individual.

156
Q

What is the mechanism of polymerase chain reaction?

A

Initial prep
sample of DNA is added to the test tube along with two DNA primers
a thermostable DNA polymerase (Taq) is added

The following cycle then takes place
mixture is heated to almost boiling point causing denaturing (uncoiling) of DNA
mixture is then allowed to cool: complimentary strands of DNA pair up, as there is an excess of the primer sequences they pair with DNA preferentially

The above cycle is then repeated, with the amount of DNA doubling each time

157
Q

What is the use of PCR?

A

prenatal diagnosis, detection of mutated oncogenes and diagnosis of infections.

158
Q

What are receptors of the cAMP system?

A

Epinephrine
- α2, β1, β2
Acetylcholine
- M2

159
Q

What ligands work by cAMP?

A

ACTH, ADH, calcitonin, FSH, glucagon, hCG,LH, MSH, PTH, TSH, GHRH*

160
Q

What is the primary effector in the cAMP system?

A

Adenylyl cyclase

161
Q

What are receptors of the Phosphoinositol system?

A

Epinephrine
- α1
Acetylcholine
- M1, M3

162
Q

What are the ligands of the Phosphoinositol system?

A

angiotensin II, GnRH, GHRH*, Oxytocin, TRH

163
Q

What is the primary effector of the phosphoinositol system?

A

Phosphlipase C

164
Q

What are the ligands of the cGMP system?

A

ANP, Nitric oxide

165
Q

What are the ligands of the tyrosine kinase system?

A

Insulin, growth hormone, IGF, PDGF

166
Q

What is the primary effector of the tyrosine kinase ?

A

Receptor tyrosine kinase

167
Q

What is the function of Th1 cells?

A

involved in the cell-mediated response and delayed (type IV) hypersensitivity
secrete IFN-gamma, IL-2, IL-3

168
Q

What is the function of Th2 cells?

A

involved in mediating humoral (antibody) immunity
e.g. stimulating production of IgE in asthma
secrete IL-4, IL-5, IL-6, IL-10, IL-13

169
Q

What is anticipation?

A

In repeat sequences, these expansions are unstable and may enlarge which may lead to an earlier age of onset in successive generations -

170
Q

Trinucleotide repeat disorders?

A

Fragile X (CGG)
Huntington’s (CAG)
myotonic dystrophy (CTG)
Friedreich’s ataxia* (GAA)
spinocerebellar ataxia
spinobulbar muscular atrophy
dentatorubral pallidoluysian atrophy

171
Q

What chromosome is HLA on?

A

chromosome 6

172
Q

If something is tagged with mannose-6-phosphate where is it destined to go?

173
Q

What cancers are associated in goblin syndrome?

A

Multiple basal cell carcinomas of the skin, along with odontogenic keratocysts (locally aggressive mandibular cysts), rib and vertebral anomalies, intracranial calcification, skeletal abnormalities, medulloblastoma and bilateral ovarian fibromas.

174
Q

What cancers are associated with Lynch syndrome?

A

hereditary non-polyposis colorectal cancer) is an autosomal dominant condition that is associated with colorectal cancer, along with malignancies of the endometrium, ovary, stomach, small intestine, hepatobiliary tract, brain and skin.

175
Q

What cancers are associated with Von Hippel-Lindau syndrome ?

A

haemangioblastomas, renal cysts and renal cell carcinoma, pancreatic neuroendocrine tumours, pheochromocytoma and endolymphatic sac tumours.

176
Q

What cancers are associated with MEN2?

A

medullary thyroid cancer, parathyroid tumours and phaeochromocytoma,.

177
Q

What are the features of Kearns Sayer disease? And inheritance?

A

Mitochondrial

Kearns-Sayre syndrome
mitochondrial inheritance
onset < 20-years-old
external ophthalmoplegia
retinitis pigmentosa

178
Q

How does breakdown of molecules from lysosomes vs breakdowns via proteasome differ?

A

Lysosome: large proteins and polysaccharides
Proteasome: polypeptides

179
Q

At what stage of the cell cycle does vincristine work?

A

Metaphase
Disrupts microtubules preventing aligning in middle

180
Q

What molecular technique is useful for determining extra chromosome copies?

181
Q

What is the most common molecular mechanism for Down syndrome?

A

Nondisjunction (maternal)
Failure of homologous chromosomes to separate in anaphase I or the failure of sister chromatids to separate in anaphase II

182
Q

What is the most prevalent immunoglobulin to least?

A

G A M (D) E

183
Q

What does Il1 stimulate?

A

secreted mainly by macrophages and monocytes and acts as a costimulator of T cell and B cell proliferation.

184
Q

What are the actions of IL-1?

A

release by the endothelium of vasoactive factors such as PAF, nitric oxide and prostacyclin it also causes vasodilation and increases vascular permeability.

Along with IL-6 and TNF, it acts on the hypothalamus causing pyrexia

185
Q

What is anakinra used for?

A

anakinra
IL-1 receptor antagonist
used in the management of rheumatoid arthritis

186
Q

What is canakinumab used for?

A

canakinumab
monoclonal antibody targeted at IL-1 beta
used systemic juvenile idiopathic arthritis and adult-onset Still’s disease

187
Q

What HLA type is reactive arthritis associated with?

188
Q

Features of cholesterol embolism?

A

eosinophilia
purpura
renal failure
livedo reticularis

189
Q

What blood test should be sent for all chronic heart failure patients?

A

NT pro BNP

190
Q

Drugs that should be added in heart failure?

A
  1. ACEI + Beta blocker
  2. Adjunct Aldosterone antagonist

Third line:
Ivabradine
Digoxin
Sacubitril-valsartan
Hydralazine

191
Q

Criteria to introduce ivabradine in

MCRP: Clinical Sciences (11 decks)

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