Block 9 Week 1 Flashcards
1
Q
Which virulence factor of streptococcus pnuemoniae allows it to attach to the respiratory linings?
A
Surface adhesins
2
Q
What are the causes of cardiogenic shock?
A
Myocardial infarction, arrythmia, pulmonary embolism with outflow obstruction
3
Q
What is infarction?
A
Obstruction of blood supply to organ/tissue
4
Q
What is the site of infection for streptococcus?
A
Nose, skin, pharynx
5
Q
What happens following necrosis?
A
Classified based on 3 morphologies:
1)Liquefactive/colliquative necrosis
2) Coagulative necrosis
3) Necrosis
6
Q
What is Liquefactive/ Collequative necrosis?
A
Digestion of necrotic cells by hydrolytic enzymes and activity of neutrophils, creating an abscess with liquid creamy tissue containing pus. This is associated with infection or brain infarction, with many cellular debris.
7
Q
What is the gross morphology of liquefactive necrosis?
A
Liquid and creamy yellow pus
8
Q
What is the micromorphology of liquefactive necrosis?
A
Neutrophils and debris
9
Q
What is an abscess?
A
Necrotic cavity containing yellow pus.
10
Q
What is pus?
A
Formed of necrotic cells and primarily dead neutrophils
11
Q
What is coagulative necrosis?
A
Occurs due to infarction. Cells maintain their architecture initially during necrosis for first few days, but become dry/firm, hard and white with a preserved outline. May result in gangrenous necrosis if it progresses to entire limb.
12
Q
Dermal papillae
A
Upward projections of dermis into epidermis
13
Q
What is fibrinoid necrosis?
A
Necrosis in small blood vessels, resulting in immune complexes forming with fibrin, causing thickening of vessel walls.
14
Q
What is gangrenous necrosis?
A
Loss of blood supply to entire limb due to coagulative nec
15
Q
What is caesating necrosis?
A
Cell death that causes cheese like appearance, commonly found in tuberculosis with the formation of lung granulomas.
16
Q
DNA of bacteria
A
Single circular chromosome and contains extracellular DNA in form of plasmid
17
Q
What is a plasmid?
A
Small strand of circular DNA which replicates independently from the chromosome
18
Q
Types of prokaryotes
A
Archae and bacteria
19
Q
What is congestion?
A
Passive process where there is excess blood accummulation or reduced blood outflow
20
Q
What causes congestion?
A
issue with heart pumping blood away from the area., venous obstruction such as mechanical compression.
21
Q
No blood supply to the region of body
A
Infarction, associated with necrosis
22
Q
Decreased/inadequate blood supply causing hypoxia
A
Ischaemia
23
Q
Scaling
A
Shedding of cornified layer of skin
24
Q
Saccular aneurysm
A
Aneurysm that bulges only on one side
25
What is purpura?
Intermediate sized haemhorrage under the skin caused by trauma or vasculitis. May be underlying cause for thrombocytopenia
26
What is petechia?
Smallest haemorrhage size caused by thrombocytopenia.
27
What is stenosis?
Narrowing of blood vessels
28
Ecchymosis
Subcutaneous haematoma due to breakdown of Hb -> Bilirubin and haemosiderin
29
Chronic pulmonary congestion
Excessive accumulation of blood in pulmonary artery. There is increased pressure on vessels which allow erythrocytes to leak out and macrophages to engulf erythrocytes and form a brownish haemosiderin
30
Neoplasia
Uncontrolled abnormal growth of cells associated with a tumour
31
Metaplasia
Environmental stimuli triggers benign change of replacement of mature cell type by different differentiated cell
32
Which stains react with anionic components?
Basic stains
33
ANeurysm
Enlargmeent of blood vessel caused by weakness in wall
34
Natural break down of blood clot
Fibrinolysis
35
Difference between fibrinolysis and thrombolysis
Fibrinolysis occurs in the body during healing process where fibrin in the clot is dissolved. Thrombolysis is the term for a group of medications to break down a clot
36
Using medication to break down clots
Thrombolysis
37
Sublethal changes to cell
Pale cyptoplasm, vacuolar degeneration, fatty changes
38
Conversion of one cell type to another
Transdifferentiation occurs in metaplasia
39
Serotyping
Identifiying antibodies based on their specificy
40
Acid fast bacteria
Kiehls- Neelsen stain is used because they resist decolourisation during typical staining due to presence of mycolic acid
41
Which sensation receptors are present in the skin?
Thermoreceptors, nociceptors, mechanoreceptors
42
Erosion
Loss of epidermis and papillary dermis
43
Infectioous eukaryotes
Fungi and parasites
44
Which glands secrete periodically?
Appocrine glands such as mamillry glands, axillae glands and groin glands. THey release via apocrine secretion into upper hair follicle, mixing with sebaceous secretion
45
Which glands secrete continuouslty?
Eccrine glands, releasing secretions of Na+ and H20.
46
Merocrine secretion
Eccrine glands- simple coiled tubular
47
Apocrine secretion
Apocrine glands - compound coiled tubular/ alveolar
48
Glands in mamillary, axillae and groin region
Apocrine gland
49
Antigenic variation
Bacteria change immunogenicity at high frequency
50
Which layer of the dermis does thermoregulation occur?
Papillary dermis
51
Desquamation
Shedding of dead corneoycytes
52
Which stage of wound healing is bacteria and damaged tissue removed?
Inflammation
53
Physical protection of skin
Against chemicals, water, infectious agents, mechanical damage
54
Superficial wound healing
Regenerate from basal layer
55
Action of lysozymes
Dissolve bacterial cell wall
56
Karyorrhexis
Fragmentation of cell nucleus due to cell necrosis
57
Pykyonosis
Shrinking/condensation of chromatin during cell necrosis
58
Lipid extrusion in epidermis
Occurs in stratum granulosum with the formation of lamellar bodies via enzymatic processing
59
which laer of epidermis do keratinocytes stop dividing?
Stratum spinosum, where they exit cell cycle and become tonofilaments
60
Late differentiation marker of keratinocytes in epidermal layer
Stratum granulosum
61
Thick skin
Contains more undulations in epidermal- dermal junction for attachment.
62
Cell type of stratum basale
Simple cuboidal
63
Decrease in number/size of cells
Atrophy
64
Dysplasia
Abnormal development of cells which is progressive, loss of cell polarity and nuclear hyperchromasia.
65
Site of hair regeneration
Hair papilla at the base of the follicle
66
Which dyes react with cationic components?
Acidic dyes
67
Composition of subcutis layer?
Loose connective tissue,
68
Hair cuticle
Plauqes which join together
69
LD50
Lethal does of bacteria which causes 50% animal mortaility
70
Toxin that is heat labile, produced by gram + and gram -
Exotoxin that has a specific target
71
Infarct
Area of necrosis caused by occlusion of arterial supply or venous drainage
72
What is the consequence of pulmonary embolism?
Cardiogenic shock
73
Bacterial cell envelope
Cell wall and cyptoplasmic membrane
74
What are the complication of aneurysm?
May rupture which causes internal bleeding. It is also a major site for clot formation or emoblisation which can lead to occlusion
75
What is a mural thrombi?
Arterial thrombi attached to the vessel wall
76
Thrombus formed under low shear-flow
Venous thrombi which is fibrin and erythrocyte rich
77
Role of peptidoglycan in gram negative bacteria
Forms periplasm to mantain bacterial shape
78
Which cell synthesises Vitamin D?
Keratinocytes in the presence of UV
79
Causes of thrombus formation
Endothelial injury, changes in intravascular pressure, hypercoagubility
80
Present of cell surface of peptidoglycan
Teichoic acid with phosphodiester bonds
81
Callus
Hyperplasia of peidermis due to pressure/friction
82
Peripheral arterial disease
Atheroma plaques in the arms and legs
83
Agar
Used as a preparation agent
84
Macconkey agar?
Differential agar to determine if bacteria can use lactose
85
Which bacteria are lactose positive?
Salmonella
86
Which bacteria are lactose negative?
E.coli
87
Karyorrhexis
Degeneration of the cell nucleus
88
Cauaes of decreased colloid oncotic pressure
Loss of protein through burns, urine due to issue with kidneys or faces in bowel disease
89
Athersoclerosis formation
Endothelial cell damage releases ROS and allows entry of LDL into tunica intima which become oxidised. This causes activation of macrophage receptors on LDL. Macrophages engulf oxidised LDL and become foam cells. These release chemokines to attract more LDL. They initiate smooth muscle migration via IgF-1 from tunica media which increases collagen generation and forms plaque. This plaque can rupture and result in coagulation and formation of clotl
90
Causes of haemhorrage?
Trauma
Atherosclerosis
Inflammation
Erosion of tumour
91
Obligate intracellular
Cannot reproduce outside the host cell and uses IC resources.
92
Extracellular
Can reproduce outside host cell
93
Ploidy
Number of sets of chromosomes
94
Hyperaemia?
Adaptive change where blood volume in tissues increases
95
Virulence
Ability to cause disease/degree of disease caused
96
Steatosis
Fatty liver
97
Which organ does metaplasia occur?
Pancreas from acinar -> duct cells
98
Which bacteria uses lactose as carbon source?
E.coli bacteria
99
Sepsis
Systemic release of IgF-1 causes vasodilation, activation of complement system of C3a and C5a with dysregulation of immune system
100
Virulence factors for salmonella
Endotoxins in LPS layer, exotoxin enterotxin that cause diarrhoea, O antigen, fibriae for adhesion
101
O antigen
Present in gram negative bacteria which prevents destruction by phagocytes
102
Cytotoxin
Inhibits host cell protein sysnthesis, causing calcium influx
103
Touch sensation of Merkel cells
DIscriminative fine touch
104
Type 3 molecules
Secreted by bacterium directly into host cell
105
Vibrio cholerae
Gram negative bacteria which increases adenylyate cyclase activitiy in the small intestine, affecting Na+ and CL- influx. Releases the enterotoxin
106
Free DNA taken up from environment
Transformation
107
Overload indicates irreversible cell damage
Ca2+
108
Where does energy production occur in bacteria?
Cyptoplasmic membrane
109
Types of acid fast bacterium
Mycobacterium, tuberculosis
110
Rete ridges
Downward projections of epidermis into dermis
111
Types of metaplsia
Squamous metaplasia in endocervix from cubodial, acinar-ductal in the pancreas and intestinal
112
Cardiogenic shock
Heart does not pump enough due to myocardial damage
113
Local congestion
Compression of blood vessels due to tumour or venous obstruction
114
Macule, patch, erythema
Lesion with skin colour issue due to melanocyte or blood flow
115
Precursor to dysplasia
Metaplasia
116
Cause of pulmonary embolus
DVT
117
Pathogens only associated with human disease
Overt/strict pathogens
118
Spores
Single celled reproductive bodies resistant to cell damage
119
Cause of sepsis
Bacteraemia (bacteria in bloodstream)
120
THromboembolsim
Blood clot which becomes stuck and occludes vessel
121
Nuclear atypia
Abnormal appearance of cell nuclei
122
Example of obligate intracellular parasite
Viruses
123
Shock caused by obstructive blood flow to heart or pulmonary artery
Obstructive shock
124
Cause of pitting oedema
Increased hydrostatic pressure
125
Most common infarct
Arterial occlusion
126
Vomiting, coughing, angina
Coronary artery blockage
127
Weakness, dysphea, facial numbness
Carotid artery blockage
128
What are the burn zones?
Coagulation zone, stasis zone, zone of hyperaemia
129
Coagulation zone
Region of burn where cell necrosis occurs which is irreversible
130
Stasis zone
Reduction in blood flow and perfusion which is reversible if oxygen supply is increased and nutrition
131
Zone of hyperaemia
Most external area which is inflammatory and has increased perfusion. Full recovery unless there is sepsis or ischaemia
132
What are the causes of lobar pneumonia?
Infection with streptoccus pneumonia that causes lung consolidation
133
What are the stages of lobar pneumonia?
Consolidation
Red hepatisization
Grey hepatization
Resolution
134
What is red hepatisation?
Lung becomes dry, airless with a liver-like consistency.RBC, WBC and debris clog the airways.
135
What is grey hepatization?
Fibrin, RBC and haemosiderin are broken down to fluid-like exudate, macrophages form and lungs turn grey.
136
Resolution in lobar pneumonia
Macrophages clear debris and leftover WBC and breakdown products are re-absorbed.
137
Alpha-haemolysin
Partial breakdown of Hb
138
Beta-haemolysin
Complete breakdown of Hb
139
What is immortalisation?
Cancer cells become immortalised and do not age due to increasing telomere production which prevents chromosomal shortening.
140
Dysplasia
Development of abnormal cell architecture, nuclear atypia and loss of cell polarity due to cytoskeletal changes. Occurs in HPV infection
141
What are the precursors to mast cells?
Basophils
142
Stratum spinosum
Contains tight intracellular junctions of desmosomes to attach to the cytoskeleton of cells
143
Downward projections in dermis
Rete ridges
144
Upward projections in dermis
Dermal papillae
145
Where do hair cells divide?
Papilla
146
What are the solid lesions?
Papule, plaque, nodule and wheal
147
What are the causes of decreased colloid osmotic pressure?
Liver cirrhosis and malnutrition
148
How can protein be lost?
Urine due to haemolytic disease
Faeces due to bowel disease
Skin due to burns
149
Which bacteria do not take up the gram stain?
Acid fast bacteria. Mycobacterium tuberculosis which has a thick waxy coat that prevents uptake
150
Conjugation
Transport of plasmid from one bacterium to another
151
Transduction
Use of bacteriophage to transmit genetic information
152
What are the stages of bacterial growth?
Lag
Exponential
Stationary
Death
153
Type 3 secreted molecule
Protein used by gram negative bacteria to inject effector proteins directly into the host cell cyptoplasm.
154
Endotoxins
Part of the LPS of gram negative bacteria which have weak toxic effects, released via cytolysis. It is generally heat labile.
155
Exotoxins
Highly toxic heat senstivie released extracellularly by gram positive and gram negative
156
What promotes the growth of clostridium dificile?
Primary bile acids promote germination of the spores. Secondary suppress growth.
157
