bams Flashcards
1
Q
name the 6 components of the chain of infection
A
.infectious agent . reservoir . portal of exit . means of transmission . portal of entry . susceptible host
2
Q
name 4 modes of disease transmission
A
. direct contact
. indirect contact
. droplet
. airborne
3
Q
define virulence
A
the ability of microbe to cause disease
4
Q
name 2 virulence factors
A
endotoxins and exotoxins
5
Q
what is the name given to a pathogen that comes from an animal?
A
zoonosis
6
Q
what are fomites?
A
contaminated objects, act as a a bridge but do not transmit infection themselves
7
Q
what is the incubation period?
A
time between contamination and development of symptoms
8
Q
what is the difference between infection and colonisation?
A
in infection the microbes make you sick whereas in colonisation the microbes are in your body but not making you sick
9
Q
what is an endogenous flora?
A
own flora
10
Q
what is an exogenous flora?
A
disease carried by microbe from external source
11
Q
how may microbes exit ?
A
coughing, sneezing, dental hand piece aerosol, blood donation
12
Q
what is an R0 in relation to an infection?
A
no. of cases one case generates on average over the course of its infectious period
13
Q
an R0 of greater than 1 indicates what
A
infection will be able to spread in a population
14
Q
an R0 of less than 1 indicates what
A
infection will die out in population
15
Q
name the 3 typeof influenza?
A
A, B and C
16
Q
which types of influenza result in major outbreaks
A
a and b
17
Q
which 2 types hepatitis are a risk for dentists and patients?
A
b and c
18
Q
describe the structure of hep a
A
. single stranded RNA genome
. non-enveloped
19
Q
how is hep a most commonly transmitted?
A
. faecal oral
20
Q
which form of hepatitis is not life threatening?
A
hep a
21
Q
what is human normal immunoglobulin therapy?
A
the use of a mixture of antibodies to treat a number of health conditions.
22
Q
how may you passively immunise against hep a?
A
human normal immunoglobulin
23
Q
how may you actively immunise against hep a?
A
vaccination
24
Q
why is vaccination for hep a preferred over normal immunoglobulin therapy?
A
vaccination is long term where as human normal immunoglobulin is only short term
25
which type of hepatitis inmost infectious?
Hep B
26
describe the structure of hep b
double sanded dna virus
27
hepatitis B is a hepadnavirus, what does this mean?
can cause acute/chronic liver failure
28
how many subtypes hep b are there?
8
29
what is the active component in the hep b vaccine?
surface antigen
30
which hepatitis virus has a very effective vaccine yet no treatment?
hep b
31
list some ways hep b can be transmitted
```
. iv drug users
. healthcare workers
. haemodialysis patients
. sexually contacts of infected people
. infants born to infected mothers
```
32
infected children have an increased chance of being a long term hep b carrier, what condition may carriers be at risk of?
liver disease
33
if somebody has been infected by hep b, how would you passively treat this?
hep b immunoglobulin from pooled plasma within 48hrs
34
what does the hep b vaccine consist of?
hep b surface antigen and aluminium hydroxide adjuvant
35
describe the structure of hep c
enveloped rna
36
how may hep c be transmitted?
```
. iv drug users
. blood contact
. organ/tissue transplant
. sexually
. vertically (mother to child)
```
37
how is hep c treated?
```
medications including:
. ribavirin
. boceprevir
. sofosbvir
. ledipasvir
```
38
hep d requires which other hepatitis for replication?
hep b
39
name all hepatitis viruses
a, b, c, d and e
40
which BBV transmitted via sharps injury is most dangerous?
hep b
41
which BBVs can be transmitted via a sharps injury?
hep b, c and HIV
42
which BBV can be transmitted via saliva?
hep b
43
which BBV is most commonly transmitted via sharps injury?
hep c
44
which BBV is most least transmitted via sharps injury?
hep b
45
what does the first A in be sharps AWARE stand for?
apply pressure and allow to bleed
46
what does W in be sharps AWARE stand for?
wash don't scrub
47
what does the second A in be sharps AWARE stand for?
assess type of injury
48
what does R in be sharps AWARE stand for?
risk of source of blood
49
what does E in be sharps AWARE stand for?
establish contact
50
in relation to a sharps injury, what does u=u means?
undetectable viral load = unable to transmit HIV
51
list some ways occupational health exposures can be reduced
```
. sharps containers
. awareness
. hand hygeine
. ppe
. vaccine
```
52
what requirements do employers have in relation to preventing sharps injuries?
. promote safe use and disposal of medical sharps
. provide info and training
. respond effectively if injury occurs
. review procedures regularly
53
what requirements do employees have in relation to preventing sharps injuries?
. notify employer as soon as practical after receiving injury
. info and training on what to do in event of injury
54
what is the definition of sepsis?
life threatening dysfunction caused by disregulated host response to infection
55
organ dysfunction in a patient suspected to have sepsis can be measured by what?
SOFA score greater than 2 points
56
is sepsis and infection?
no but it doesn't not occur in the absence of infection
57
what differentiates infection from sepsis?
present of organ dysfunction in sepsis
58
the range of tests that test organ function are collectively known as?
qSOFA
59
which type of microbes cause sepsis?
. gram positive bacteria
. gram negative bacteria
. fungus
60
which type of microbe most commonly cause sepsis?
gram negative bacteria
61
which microbial factor may cause infection to progress to sepsis?
. virulence factors
62
which host factor may cause infection to progress to sepsis?
```
. innate immunity (non specific)
. adaptive immunity
. immunocompromised
. pre existing chronic condition
. age
. genetics
```
63
which age group most commonly get sepsis?
elderly
64
describe the pathophysiology of sepsis?
. dysregulated, excessive systemic inflammation
. body-wide blood clotting and leaky vessels
. 1 or more organs begin to fail
.perisitent hypotension
65
in the event of inflammation, our innate immunity recognises PAMPs (pathogen associated molecular patters) and DAMPs (damage associated molecular patterns) via which which molecules?
PRRs
66
inflammation is triggered by the release which two immune cells?
cytokines and chemokine
67
what is used to treat sepsis?
. antibiotics
. fluids - colloids and crystalloids
. vasopressors
68
why do dentists need to be educated on sepsis?
. dental infections may cause sepsis
69
what are the red flag symptoms of a spreading dental infection?
```
. temperature over 36
. elevated breathing
. increased or decreased heart rate
. facial swelling
. trismus
```
70
is the ICF negative or positive in relation to the ECF?
negative
71
which ion is most prominent in the ECF?
sodium
72
which ion is most prominent in the ICF?
potassium
73
at resting potential, is the membrane permeable or impermeable to sodium ions?
impermeable
74
at resting potential, is the membrane permeable or impermeable to potassium ions?
very permeable
75
what is the resting membrane potential mainly due to?
diffusion of potassium ions from inside the cell
76
what is the AP threshold
-55mV
77
during the upstroke of the AP, which ion enters the neuron?
sodium
78
which ion is moved out of the neuron during the downstroke of the ap?
potassium
79
volage gated sodium channels have two gates, name these
m gate and h gate
80
describe the position go the m and h gate when the sodium channel is closed
. m gate closed
| . h gate open
81
describe the position go the m and h gate when the sodium channel is open
. m gate open
| . h gate open
82
describe the position go the m and h gate when the sodium channel its closed during refractory period
. m gate open
| . h gate closed
83
what happens when the AP threshold is met?
. sodium ion channels open
. sodium influx
. increased depolarisation
. potassium channels remain shut
84
what happens when the AP reaches +35mV?
. sodium channels shut
. h gate is inactivated
. potassium channels open
. potassium reflux begins
85
the refractory period is due to what?
inactivation of h gates on sodium channel
86
what is the refractory period of an AP?
after AP is generated, neuron cannot generate another until the 1st has ended
87
increasing axon diameter has what effect on speed of ap propagation?
increased speed
88
which size of axons, small or large conduct impulses faster?
large
89
which cells lay down myelin?
glial cells (oligodendrocytes in CNS and schwann cells in PNS)
90
the myelin sheet is interrupted at intervals called?
nodes of ranvier
91
the propagation of action potentials along myelinated axons from one node of Ranvier to the next node is called?
saltitory conduction
92
which axon type is unmelinated?
c fibres
93
what effect does LA have on a nerve?
blocks voltage gated sodium channels preventing sodium influx, therefore blocking AP generation and propagation
94
list the nerves in order of most to least susceptible to LA block
a delta
c fibres
a beta
a alpha
95
what is the sensory function of a alpha (group i) nerve fibres?
proprioception
96
what is the sensory function of a beta (group ii) nerve fibres?
mechanoreceptors
97
what is the sensory function of a delta (group iii) nerve fibres?
. mechanoreceptor,
. thermoreceptor,
. nociceptor,
. chemoreceptor
98
what is the sensory function of c (group iv) nerve fibres?
. nociceptor,
. thermoreceptor,
. chemoreceptor
99
why does LA have a risk of bradycardia and hypotension?
it also blacks sodium channels in other excitable tissues, for ex the heart muscle
100
LA is an organic molecule consisting of 3 components, what are these?
. aromatic region (hydrophobic)
. ester or amide bond (intermediate)
. basic amine side chain (hydrophilic)
101
which types of nerves are most easily blocked by LA?
small myelinated
102
why are myelinated nerves more susceptible to LA block?
they only need blocked at nodes of ranvier
103
list the following, autonomic nerves, sensory nerves and motor nerves in order of most susceptible to LA
. autonomic
. sensory
. motor
104
in dental LA what is the base?
hydrochloride
105
what is the ester in dental LA?
benzocaine
106
what is the amide in dental LA?
lignocaine, prilocaine etc
107
are LAs vasoconstrictor or vasodilators?
vasodilators
108
name 2 common vasoconstrictors added to LA?
. adrenaline
| . felypressin
109
which 4 types of receptors does adrenaline act on?
. a receptors (vasoconstriction)
. beta 2 (vasodilation)
. beta 1 (cardiac muscle)
. ADH receptos
110
given locally, adrenaline has what effect on BVs?
vasoconstriction
111
how is the ester in LA broken down?
tissue esterases (short action)
112
how is the amine in LA broken down?
liver amidases (long action)
113
list 6 modes of LA administration
```
. topical
. local infiltration
. regional nerve block
. injection
. nerve root block (epidural)
. IV
```
114
what is the max dose for lignocaine?
4mg per kg body weight
115
in ECF, the principle cation is _ and the principle anion is _?
cation - sodium
| anion - chloride
116
in ICF, the principle cation is _ and the principle anion is _?
cation - poatssum
| anion - phosphate
117
sodium and postassium may cross the membrane against the conc gradient via?
sodium potassium pump
118
why r smaller axons more susceptible to LA?
they have less fewer voltage gated sodium channels permit of area
119
which senses are blocker first by LA?
pain and thermal senses
120
what is a high risk (critical) dental environment or piece of equipment?
items in contact with normal sterile body sites
121
what is a medium risk (semi-critical) dental environment or piece of equipment?
items in contact with mucous membranes
122
what is a low risk (non-critical) dental environment or piece of equipment?
items in contact with intact skin
123
what is a minimal risk dental environment or piece of equipment?
not normally in contact with intact skin
124
compare gingivitis and periodontitis
```
gingivitis
- inflammation localised to gingivae
- acute inflammation
- normal physiological response to infection
periodontitis
- inflammation of all periodontal tissues
- chronic inflammation
pathological inflammation
```
125
compare infection and colonisation
infection - micro-organisms causing damage to body tissues, usually in presence of acute inflammtion
colonisation - bacteria grow on body sites exposed to the environment causing infection
126
name 3 periodontal pathogens
p. gingivalis
t. forsytha
t. denticola
127
list some immune defences in the oral cavity?
gingival crevicular fluid - AMPSs, chemokine,cytokines, lactoferrin, IGA
oral mucosa - AMPs, cytokines, chemokine
saliva - IgA, lysosomes, peroxidase, lactoferrin, muffins, cystatins, histatins
128
what is the initial predominant cell type in gingivitis?
neutrophil
129
which ligand induces osteoclast differentiation?
RANKL
130
which substance prevents RANKL binding RANK?
OPG
131
all microbes in the human body are known as the?
microbiome
132
a community of microbes that live together on a surface are known as?
biofilm
133
which outnumbers which, microbes or body cells?
microbes out weigh body cells 10:1
134
list these in order of smallest to largest, bacteria, helminth, virus and fungus
virus (smallest)
bacteria
fungi
helminth (largest)
135
what are the benefits of normal flora?
synthesis and excrete vit k dan b12
prevent colonisation by pathogens
stimulate development of specific tissues
136
list the 4 criteria for koch postulates?
- microbe present in every case of disease
- microbe isolated from host and grown in pure culture
- disease reproduced when pure culture introduced to susceptible host
- microbe recovered from experimentally infecting host
137
name some methods of physical growth control of microbes?
heat sterilisation
| radiation sterilaisation
138
name some methods of chemical growth control of microbes?
antiseptics (biological) and disinfectants (inanimate)
natural antimicrobials
synthetic antimicrobials
139
strong chemical agents that inhibit or kill microorganisms are known as?
disinfectants
140
disinfectant agents with sufficiently low toxicity for host cells are known as?
antiseptics
141
which are used on mucous and skin, disinfectants or antiseptics?
antiseptics
142
describe selective toxicity in terms of antiseptics?
toxic to micro-organisms but not to human cells
143
antiseptics can be classified in 2 ways, what are these and which is preferred?
cidal (preffered) or static
144
describe what is meant by a cidal antiseptic?
denatures proteins
| cause osmotic disruption of cell
145
describe what is emanate by a static antiseptic?
interfere with specific metabolic processes
146
which type of disinfectants oxidise SH groups of proteins and enzymes producing SS bonds which disrupt structure and function?
iodophors
147
which disinfectant is most effective against gram positive cocci?
chlorohexidine
148
are antibiotics naturally occurring or synthetically produced?
naturally occurring
149
what is the definition of an antibiotic?
chemical substance produced by 1 organism that is destructive for another
150
list some properties of an ideal antimicrobial?
selective toxicity against target
minimal host toxicity
cidal activity
long plasma 1/2 life
151
what may antimicrobials target?
inhibit cell wall synthsis
inhibit protein synthesis
inhibit essential metabolite synthesis
injure plasma membrane
152
for the bacteria S. aureus, give a description, its virulence factor and a disease it can cause
gram positive cocci
PVL toxin
impetigo, pneumonia
153
for the bacteria S. pyogenes (group A strep), give a description, its virulence factor and a disease it can cause
gram postive in chains
super antigenic and toxic shock syndrome
meningitis, arthritis
154
for the bacteria S. anginosus, give a description, its virulence factor and a disease it can cause
gram positive in chains
cytotoxin
dental abscess
155
for the Herpes simplex virus, give a description, its virulence factor and a disease it can cause
fried egg virus
cause cell lysis
herpies labialis
156
for the fungus candida albicans, give a description, its virulence factor and a disease it can cause
gram positive
phosoplipidase
candidiasis
157
give an example of an infection of the epidermis and which organism(s) can cause it
impetigo - group a strep or staph aureus
| angular chelitis - candida albicans
158
give an example of an infection of the dermis and which organism(s) can cause it
erysipelas - group a strep
159
give an example of an infection of the hair follicle and which organism(s) can cause it
folliculitis - staph aureus
160
give an example of an infection of the subcutaneous fat and which organism(s) can cause it
cellulitis - group a strep
161
give an example of an infection of the fascia and which organism(s) can cause it
necrotising fasciatis - group a strep and other bacteria
162
give an example of an infection of the muscle and which organism(s) can cause it
myonecrosis - c perfinigens
163
surgical wound infection are usually caused by which microorgansism?
staph aureus
164
during the immune response, which is low specificity and high and which is procured 1st, IgM or IgG?
low specificity IgM produced fist
| high specificity IgG takes longer as require T cell help
165
which type of antibodies are responsible for secondary response to infection?
IgG
166
a vaccination containing a live microorganism weakened via genetic manipulation is known as ?
live attenuated vaccine
167
a vaccine containing a microorganism killed through chemical or physical processes is called?
inactivated vaccine
168
a vaccine containing no live components is ?
subunit vaccine
169
which type of vaccine gives best immunity?
live attenuated
170
which substance is added to vaccinations to increase immune response?
adjuvant
171
name some conventional immunosupressive drugs
corticosteroids
NSAIDs
methotrexate
biological therapies
172
name synthetic cortisol
prednisolone
173
name a disease modifying anti-rheumatic drug (DMARD)
methotrexate
174
genetically engineered antibodies from human genes that target the immune response is what type of treatment?
biological therapy
175
what is the aim of vaccination?
stimulate adaptive immunity and generate long-term immunological memory
