Test #2 Microbiology Test Flashcards
1
Q
What a cell needs to survive is known as ___.
A
*essential nutrients
2
Q
- Macronutrients are also called ___.
- 3 elements involved are: ___, ___, and ___.
A
- trace elements
* carbon, hydrogen, and oxygen
3
Q
___ are everything else an organism needs but not quiet so much of.
A
*micronutrients
4
Q
4 categories of essential nutrients:
A
- macronutrients
- micronutrients
- inorganic
- organic
5
Q
Organisms need lots of ___.
A
*carbon
6
Q
Inorganic is not based on ___ and ___.
-ex: salt and sodium chloride
A
*carbon and hydrogen
7
Q
Organic is based on ___ and ___.
-ex: carbs, lipids, and proteins
A
*carbon and hydrogen
8
Q
Cell are made up of ___% of water.
A
*70%
9
Q
___% of dry weight of cell is made of organic compounds.
A
*97
10
Q
96% of dry weight of cell is made of ___.(6)
A
*carbon, hydrogen, O2, nitrogen, phosphorus, and sulfur
CHONPS
11
Q
An essential nutrient for ALL organisms is ___.
A
*carbon
12
Q
Autotrophs get carbon from ___.
A
*carbon dioxide
13
Q
Heterotrophs get carbon from ___.
A
*from an organic source, they have to eat plants or animals
14
Q
One specific heterotroph is an ___. And they feed on dead organisms, they are decomposers.
A
*saprobes
15
Q
Iron is a trace nutrient for many organisms, does it make it more or less important than carbon?
A
*no, they are equally important
16
Q
___ is a trace nutrient for humans, without it you could get goyders or metabolism malfunctions.
ex: salt
A
*iodine
17
Q
Trace nutrients vary ___ from organism to organism.
-ex: cooper is important for pigs but will kill sheep
A
*widely
18
Q
- When bacteria can grow in a wide range of conditions.
- Can withstand a bunch of situations to grow, grows everywhere.
A
*facultative
19
Q
- When bacteria has a narrow range (niche) to grow.
- Must have certain temp, gases to grow and grow in defined places.
A
*obligate
20
Q
Minimum Temp for an organism to grow, it doesn’t kill them, just stops the from growing. (sleep)
A
*minimum temperature
21
Q
The temperature that an organism grows best at, can be very narrow or wide.
A
*optimum temperature
22
Q
Temperature at which it is the death point for an organism.
A
*maximum temperature
23
Q
- Cold temperatures below 15C, obigates need to be under 20C unless they will die.
- rarely pathogenic, live in ice or deep ocean
A
*psychrophile
24
Q
- Grow slowly, 15-30C, food born illnesses can grow
- Lasteria grows best in refrigerator
A
*psychotroph
25
- Human pathogens 20-40C
| - 37C=98.6F in humans
*mesophile
26
- Can be cultured in autoclave
| - 45C and up, most are found in volcanic regions, not human pathogen
* thermophile
| * extreme thermophile
27
Organisms that are mesophiles, they can survive pulses of very high heat, can boil and not kill them.
ex: protozoan gilambia
*thermoduric
28
Requires O2. Bacteria, fungi, protozoa, and TB are all___.
*aerobes
29
- Like a little bit of O2.
- Organisms live in soil, water, humans
ex: lime disease, ulcers
*microaerophiles
30
Organisms that do not use O2 are called ___. There are 3 types:
* anaerobes
| * facultative, aerotolerant, obligate
31
Can exist in O2 but doesnt have to use it.
| ex: staph, e-coli
*facultative
32
Will not use O2 EVER because it will kill them.
*aerotolerant
33
Must be in an environment with no O2, its toxic to them, they will die b/c they are lacking certain enzymes.
*obligate
34
Certain type of media we can use, put bacteria in and grow, then you can discover if its anaerobe or aerobe based on growth pattern.
*thyoglycade broth
35
-Organisms that like carbon dioxide, they grow best with it.
*capnophiles
36
CO2 requirements are ___ related to O2 requirements.
*not
37
2 requirements for human pathogens:
* temperature(mesophiles 37C)
| * gas (any organism can find a home on your body for gas)
38
They can not find a niche on the human body and that is why they are not human pathogenic.
*archaea
39
Most microbes like "the middle" but there are exceptions: (3)
* pH-7 is neutral
* osmotic pressure (isotonic solutions like)
* pressure (organisms dont like high pressure
40
___ kills most microbes.
*salt
41
Microbes that like salt, can be obligated or facultative.
| ex:staph arious
*halophiles
42
Microbes that like pressure, they live in deep sea.
*barophiles
43
Organisms that live in close association with each other.
*symbiotic
44
- mutualism
- commensalism
- parasitism
are ____.
*symbiotic
45
- synergism
- antagonism
are ___.
*non symbiotic
46
Symbiotic Relationships:
Relationship Host Commensal/Dependent
Mutualism
Commensalism
Parasitism
* + +
* = +
* - +
47
Two things working against each other.
*antagonism
48
Two things working together.
*synergism
49
___ is film/slime that happens all over. They are an example of synergism.
*biofilms
50
Organisms keeping track of each other is called ___.
*quarum sensing
51
___ bacteria can be the same species or a whole new species.
*new
52
In ___ bacteria are leaving together to help each other but can move on if it wants to.
*synergism
53
___ growth is growth in numbers.
*bacterial
54
5 steps of binary fission:
* enlargement
* duplication of bacteria chromosome(exact copy)
* protein band forms to divide cell
* formation of septum, divides cell
* formation of cell wall of peptidoglycan, either apart or linked
55
Bacteria are produced and grow by ___.
*binary fission
56
How long it takes to complete 1 fission cycle is called ___.
*generation time
57
Generation time varies widely by:
- 10-12 min
- hours, days, months
- ___ to ___ min average
*30 to 60 min
58
Pathogens generate quick ___ min.
*20 min
59
Nt = (Ni)2n is the equation for ___.
- Nt is the ____
- (Ni) is the ___
- n is the ___
*exponential growth
* final # of bacteria
* initial # of bacteria
* # of generation total time/generation time
60
In a lab setting the exponential growth equation is not realistic because ___.
*bacteria run out of nutrients and they starve and drown in their own waste.
61
How to calculate bacteria in a more realistic way:
- tube of sterile liquid and add cells
- incubate under optimum conditions
- take samples over a couple of hours
- count by colonies
*viable count technique
62
Colony Forming Units (CFU) x Volume =
*estimate of total population
63
Graph over time ---> growth curve
| -gives a more ____ of how bacteria grow.
*realistic picture
64
5 steps in growth curve:
* lag phase
* exponential growth phase (log phase)
* stationary phase
* death phase
* viable none cultural state
65
Phase that takes time for bacteria to adjust b/c:
- takes tine for bacteria to get maximum speed of cell division
- lab error, broth may be to dilute
*lag phase
66
The maximum rate of cell division phase:
*exponential growth phase (log phase)
67
The growing and dying at the same rate phase:
*stationary phase
68
Phase when cell have no food and are starving and drowning in their own waste, bacteria dying faster then multiplying:
*death phase
69
The sleep phase:
viable none cultural state
70
So how is all this clinically irrelevant ? (4)
* effectiveness of antimicrobial agents
* spread of disease
* course of disease
* chemostats
71
____ agents accelerates the death phase, most effective in the log phase.
*antimicrobial
72
Diseases spread more likely in ____ phase.
*log
73
The earlier part of the growth curve.
*course of disease
74
Continuous culture and head of the growth curve and keeps exponential growth going, are helpful in studying disease.
*chemostats
75
3 ways of counting without culturing:
* turbidity
* counting
* genetic probing
76
The more bacteria in it, the more cloudier it will be.
*turbidity
77
Putting bacteria on a slide and counting cells one by one.
*direct count
78
Counts cell by using a machine with laser.
*coulter count
79
Can tell more about cells, how big they are, how many are alive, how many are dead.
*flow cytometry
80
Real time pcr, monitor how fast cells divide using genetic code.
*genetic probing
81
Will the growth on an undercooked hamburger continue to grow at the same rate forever?
*no b/c nutrients will run out and the microbes will start to drown and starve in their own waste.
82
4 ways to kill microbes:
* sterile
* disinfect
* sanitize
* antisepsis
83
Remove pathogens to a safe level, not getting rid of viruses (decontamination).
*sanitize
84
Disinfecting on tissue, degerming. (alcohol)
*antisepsis
85
Clean as possibly can get, rid of viruses, toxins,vegetated pathogens, and gets rid of ENDOSPORES.
*sterilize
86
Everything sterile, but doesnt get rid of endospores.
*disinfect
87
___ is the hardest microbe to kill, you need 121 degrees C.
*endospore
88
Gram ___ is harder to kill then gram ___.
*negative, positive
89
If a microbe is really dead, it will never ___ again, even under ideal conditions.
*reproduce
90
___ means pressing pulse, slowing growth of microbes down.
*static
91
___ means dead, killing. May be too dangerous to do.
*cidal
92
4 factors that influence the action of antimicrobials:
* kind of organism
* # of organisms
* temp and pH
* amount and delivery (concentration)
93
4 targets of antimicrobials:
* cell wall
* cell membrane
* cellular synthesis
* proteins
94
In ___ antimicrobials block synthesis and digest it.
*cell walls
95
In ___ antimicrobials bind lipid layer and opens up the cell (makes a hole), and bad stuff IN, good stuff OUT.
*cell membrane
96
In ___ the antimicrobial attacks ribosomes and mutates genetics.
*cellular synthesis
97
In ___ the antimicrobial denatures it (unwines) and attach to active sites to block action (shut down enzymes).
*porteins
98
3 things that can physically control microbes:
* heat
* filter sterilization
* radiation
99
___ and ___ does not physical control microbes.
* freezing
| * drying
100
___ kills some, but induces endospores in others.
*dessication (drying)
101
___ kills very few, slows microbial metabolism in most, and warm it up and the microbes grow again.
*freezing
102
___ is freeze drying to preserve.
*lyophilization
103
___ is dehydration and permanent protein denaturation.
- thermal death time
- thermal death point
*heat
104
___ is how long it takes to kill microbes at a given temp.
*thermal death time (TDT)
105
___ is what temp will kill a given microbe in 10 min.
*thermal death point (TDP)
106
___ is incineration and roasting.
*dry heat
107
___ is boiling, pasteurization, unpressed steam, and pressurized steam sterilization.
*moist heat
108
```
___ burns the microbes.
pros:
-very high temp 800-6500C
-quick
-effective
cons:
-creates aerosols (smoke)
-not good for liquids
```
*incineration
109
```
___ uses an oven.
pros:
-achieve high temp 150-180C
-good for objects that shouldnt get wet
cons:
-takes 2-4 hours
-some items may burn
-not good for liquids
```
*roasting
110
___ is moisture penetrating cells better than dry air.
pros:
-good for non lab needs
-30 min will sanitize household objects
cons:
-limited to 100C (not enough to kill endospores)
-recontamination out of water
*boiling
111
___ is used for food and beverage.
| -process is flash or batch
*pasteurization (moist heat)
112
Flash is ___C for 15sec. Preferred for food b/c it doesnt change taste.
Batch is ___ to ___C for 30min.
* 71.6C
| * 63 to 66C
113
```
Pros:
-good for food
-kills 97-99% of vegetative pathogens
Cons:
-disinfects, does not sterilize
```
*pasteurization
114
___ is also called tyndallization (intermittent sterilization).
Intermittent steaming 30-60min for 3 days at 100C.
pros:
-germinates many spores, then kills
-good for heat sensitive that wont survive autoclave
cons:
-limited to 100C
-some resistant spores may still survive
*unpressurized steam
115
___ is autoclave, higher pressure(15psi) raises BP of water to 121C.
pros:
-sterilize media in 15min
-cons:
-some media additives(vitamins and nutrients) destroyed at high temps
-dangerous if autoclave malfunctions
*pressurized steam sterilization
116
___ can survive autoclave.
*prions
117
___ is UV rays that interfere with DNA replication in microbes.
pros:
-kills endospores
-can be done on a large scale(entire room)
-good for things harmed by heat
cons:
-not effective on liquids in glass
-can harm humans and some media additives
*radiation
118
```
___ uses a specialized filter that filters out all bacteria and many viruses.
pros:
-doesnt change media
-good for heat sensitive materials
cons:
-wont work on viscous material
-cant filter impurities or toxins
-doesnt kill anything
```
*filter sterilization
119
4 factors in chemical control:
* material being treated
* length of exposure
* concentration of germicide
* microbe being treated(virus, endospore,vegetated pathogen)
120
2 ways of chemical control:
* gas sterilization
| * chemical disinfectants
121
___ has many options and can be aqueous or tincture.
*chemical disinfectants
122
___ is a water solution.
| ___ is an alcohol solution.
* aqueous
| * tincture
123
___ is ethylene oxide that disrupts DNA replication.
pros:
-good for delicate intruments
-good for intruments not affected by UV lights
cons:
-carcinogenic
-explosive
*gas sterilization (never first choice)
124
```
___ are iodine and chlorine.
Disrupts enzymes and metabolic functions.
pros:
-kills all microbes including spores(slowly)
cons:
-irritating to skin
-takes time to work
-can be toxic
-organic matter gets in the way
```
*halogens
125
___ is a colorless that forms free radicals which are highly toxic to cells.
Antiseptic at low concentration 3%
pros:
-kills all microbes including spores
cons:
-requires high concentration to kill spores 35%
*hydrogen peroxide
126
___ are little molecules that destroy cells.
*free radicals
127
```
___ are glutaraldehyde and formaldehyde that disrupt enzyme activity and nucleic acids.
pros:
-sterilizes
-broad spectrum
-relatively quick(glutaraldehyde)
cons:
-unstable
-toxic
-skin irritant
```
*aldehydes
128
___ are derived from coal tar.(ex:triclosan). Disrupts cell wall or certain enzymes.They sanitize.
pros:
-standard for other chemical antimicrobials
cons:
-can be dangerous as antiseptics(toxic)
-very limited use
*phenols
129
___ are complex combination of chlorine and phenolic rings(ex:ReNu). They destroy bacterial membranes and denature proteins.
pros:
-mild with low toxicity
-fast
cons:
-variable effectiveness on viruses and fungi(not to effective)
*chlorhexidine
130
```
___ are ethanol or isopropanol over 50% (70% is ideal), they disrupt cell membrane.
pros:
-non irritating
-cheap
cons:
-rate of evaporation
-vapors may affect nervous system
```
*alcohol
131
Several different types(ex: quaternary ammonium compounds), that disrupt selective permeability of cell membrane.
pros:
-good for everyday cleaning
-effective on viruses, algae, fungi, and GP bacteria
cons:
-not good for clinical setting
-effectiveness reduced by organic matter
*detergents
132
```
Silver and Mercury(toxic), disrupts protein function.
pros:
-effective antiseptics
cons:
-not effective on endospores
-can be extremely toxic
```
*heavy metal compounds
133
3 reasons why viruses are not considered alive:
* not cells
* need a host for reproduction
* will always contain DNA or RNA, which one depends on virus
134
6 interesting facts about viruses:
* incredibly abundant(outnumber bacteria and are on every surface)
* very very tiny
* not alive (active vs inactive)
* obligate intracellular parasites(living inside a cell)
* 10% of human genome(viral dna)
* will infect ANYTHING
135
- For every single host, their is a ___.
- Specific viruses have specific ___.
- Viruses can infect other animals, bacteria, protozoa, and fungi.
* virus
| * host
136
2 old systems of classifying and naming viruses:
* host(animal or plants)
| * genetic information(DNA or RNA)
137
3 viral groups:
* orders
* families
* genera
138
Swan flu and the common cold are examples of ___ names.
*common vernacular
139
A viruses size is:
-1mm=1000um(micro meters)=1,000,000___.
-20nm to ___nm in diameter.
cylindrical viruses may be long(800nm) but thin.
* nm (nano meters)
| * 450nm
140
You need a ___ microscope to see viruses.
*electron
141
- The inside of a virus has a ___ with DNA and RNA.
| - Some viruses have extra pieces called ___.
* core
| * enzymes
142
2 main viral particles:
* covering
| * core
143
- Outside portion of virus is called ___.
| - ___is like a cell wall, some viruses have.
* covering
| * envelope
144
Every virus must have, contains capsid and DNA/RNA.
*nucleocapsid
145
Repeated subunits that create capsids.
*capsomeres
145
- If a virus has an envelope, it is called an ___ virus which wraps around the capsid.
- If a virus has a capsid, its called a ___ virus.
* envelope
| * naked
146
If a virus has an envelope, it is called an ___ virus which wraps around the capsid.
*envelope
147
3 shapes of a capsid:
* helical
* icosahedral
* complex
148
Made of stacked halo discs.
*helical
149
3D shape with 20 sides, 12 corners that forms a shell.
*icosahadral
150
These are non symetrical bacterial phages.
*complex
151
Fully formed functional viruses that are capable of causing infection.
*virion
152
3 types of envelopes:
* stolen
* spikes
* pleomorphic
153
Viruses that are not constricted to a certain shape.
*pleomorphic
154
- Envelopes are ___ from the host cell.
| - ___ are glycoproteins that aid in attachment of cells.
* stolen
| * spikes
155
Has a double helix, can be linear or circular, can integrate into our DNA and become part of us.
*dsDNA
156
One half of an DNA ladder.
*ssDNA
157
Makes since to cell and immediately new viruses are built.
*positive sense RNA
158
Has to be converted to positive RNA, then new viruses can be built.
*negative sense RNA
159
Looks like dsDNA, very rare.
*dsRNA
160
___ is a retro virus, they can make DNA from RNA.
| -ex:HIV
*RNA with reverse transcriptase
161
3 types of enzymes:
* polymerases
* replicases
* reverse transcriptase
162
- Like glue, help build new RNA/DNA is ___.
| - Aids in copying RNA are ___.
* polymerases
| * replicases
163
A animal virus takes __ to __ hours to be created and released.
*8 to 36 hours
164
5 stages in making a animal virus:
* adsorption
* penetration and uncoating
* synthesis
* assembly
* release
165
For every host their is a virus, receptors on cell and virus need to match. This is called ___.
*host range
166
These are tissue viruses that require a certain type of tissue.
*tropisms
167
In this stage the virus locks on a cell and is limited by receptors on virus and cell called glycoproteins(spikes). Then endocytosis occurs.
*adsorption
168
In this stage the virus is engulfed by the cell and brings a piece of its membrane. Then uncoding occurs.
*penetration
169
In this stage the virus is engulfed by the cell and brings a piece of its membrane. Then encoding occurs.
*penetration
170
Process that dissolves all the stuff that is holding genetic information and the virus genetic information is floating free.
*uncoding
171
- An RNA virus will remain in the ___ and do its work.
| - An DNA virus will enter the ___ and do its work.
* cytoplasm
| * nucleus
172
In this stage viral DNA/RNA will build pieces to make a new virus.
*synthesis
173
In this stage DNA/RNA make a nucleocapsid, it spikes and moves into host cell membrane to get ready to be released.
*assembly
174
In this stage either the cell will rupture(lysis) or a naked virus forms and bust the cell and release virus, find spikes and move on or a envelope virus forms and will pinch of cell membrane, poke spikes out and move on.
*release
175
3 long term effects of viral infections:
* cytopathic effects
* persistent infections
* viruses and cancers
176
3 cytopathic effects:
* size/shape changes
* inclusion bodies
* syncytia
177
A bunch of cells coming together and becoming a clump, happens in non functional cells.
*rounding up
178
This is the left over trash from virus factory, they can be nucleoid or cytoplasmic.
*inclusion bodies
179
Mutinucleoid, a fusion of cells that are not functional b/c they are fused together.
*syncytia
180
In these infections the cell harbors virus, and it takes a few weeks to or forever. It has an provirus state and chronic latent state.
EX: varicella zoster virus. Which is chicken pox which can later be shingles
*persistent infections
181
Viral DNA as part of host DNA but is inactive is called ___.
*provirus
182
Virus that is not active but just hanging around is called ___.
*chronic latent stage
183
Viruses that can cause cancer are called ___.
| EX: HPV, hep B, and Epstein bar virus
*oncogenic viruses or oncoviruses
184
Viruses that can cause cancer are called ___.
*oncogenic viruses or oncoviruses
185
Transformations of viruses and cancer: (4)
* growth rate
* chromosome changes
* surface molecules
* division
186
When diagnosing cancer you are looking for an ___ molecule.
*surface
187
A ___ is a virus that effects bacteria. It still goes through adsorption but injects DNA/RNA only into the cell.
*phage
188
The big difference between phage and animal life cycles are, phage ___ DNA into the cell.
*injects
189
2 options for the phage cycle:
* lytic
| * lysogenic
190
- Similar to animal cycle
- Phage attaches using tail fibers, injects, then DNA goes through cycle
- Cell lyses(burst), new virus is released.
*lytic cycle
191
- Temperate phages adsorb and penetrate
- Insert into host DNA causing prophage state
- induction
*lysogeny
192
In lysogenic phage the host DNA takes viral DNA and is inactive is called ___.
*prophage state
193
When a bacteria phage injects DNA and it becomes part of bacterial DNA, bacteria gets a new trait or ability that can produce a toxin.
*Lysogenic Conversion
194
3 lysogenoc conversion toxins: disease is toxic b/c of bacterial phage
* diphteria
* cholera
* botulinium
195
- Infectious protein particles that look like misfolded proteins
- Smaller/simpler than viruses
- Affects brain tissue and can cause spongiform encephalopathies.
- no cure
*prions
196
Depends on other viruses for replication.(piggy backing)
- adeno-associated virus
- delta agent
*satellite viruses
197
Depends on other viruses for replication.
- adeno-associated virus
- delta agent
*satellite viruses
198
Satellite virus in a cell that already has an adeno virus, it just sits there.
*adeno-associated virus
199
Satellite virus that is naked with RNA and piggy backs off hep B which causes liver damage, this virus makes liver damage more severe.
*delta agent
200
- plants
- smaller than viruses
- naked RNA
- EX: TMV, which wipes out tobacco fields
*viroids(plant viruses)
201
Its impossible to come up with a number of viruses in humans b/c:
*they dont get reported
202
- Acute infections (get it and get over it)
- Important regional viruses
- high mortality
- long term disability (polio)
- possible connections to chronic afflictions (MS)
*around the world
203
Diseases that dont have a cause maybe caused by viruses are called ___.
*chronic afflictions
204
5 tx's and preventions of viruses:
* antibiotics
* antivirals(used for flu,HIV)
* interferon (natural chemical in body)
* vaccines
* zinc
205
Blocks absorption and replication of viruses.
*zinc
206
Anytime we use a chemical to treat, relieve, or prevent disease.
*chemotherapy/chemotherapeutic agent
207
- Subset of chemotherapeutic drugs
| - Basically disinfectants or sanitizers administered to pts as medication
*antimicrobial drugs/antimicrobic agent
208
What would make an ideal antimicrobial drug?
* selective toxicity
* low side effect
* cheap
* dont have to take for a long period of time
209
Targeting what's making a person sick without killing host cells.
*selective toxicity
210
Years ago antimicrobials were toxic to ___ and ___.
* bacteria
| * pt
211
___ in 1909 creates salvarsan to tx syphilis.
*Paul Ehrlich
212
___ in 1928 discovered penicillin, first antibiotic. Mass produced in 1944.
*Alexander Fleming
213
Antimicrobic agent produced by another organism.
*Antibiotic
214
Synthetic , antibiotic created in a lab.
*second/third generation antibiotic
215
Antibiotic effective to wide range of organisms.
*broad spectrum
216
Antibiotic made for a specific disease.
*narrow spectrum
217
2 common sources of antibiotics:
* bacteria
| * molds
218
- bacillus
- streptomyces
are examples of a ___ antibiotic.
*bacteria
219
- penicillium
- cephalosporium
are examples of ___ antibiotics.
*mold
220
3 major factors in determining what antimicrobial to use:
* identify the offending organism
* sensitivity of organism to drugs
* condition of pt
221
After the bug is identified you have to figure our what to you and what dose, this is done by using one of these 2 options:
* Kirby-Bauer Test
| * Minimum Inhibitory Concentration (MIC)
222
- Spread pure culture of bacteria on Mueller-Hinton agar
- Place small paper disks impregnated with antibiotics on the plate
- incubate overnight 37C
- Interpret: minimum zone of inhibition=sensitivity
*Kirby-Bauer
223
This is where the bacteria wont grow on the plate.
*zone of anti-inhibition
224
The zone where bacteria is more sensitive
*big zone
225
The zone where bacteria is less sensitive
*small zone
226
Pros of ___:
- easy with pure culture
- highly reproducible
- in vitro results usually match in vivo results(what you see on the plate matches the person)
*Kirby-Bauer
227
Cons of ___:
- not reliable with anaerobes or slow growers
- qualitative, not quantitative (dont know how much to give)
*Kirby-Bauer
228
- Prepare antibiotic at a known concentration(10ug/ml)
- Serially dilute by 1/2 each time
- Inoculate organisms being tested into each tube
- Incubate 37C under optimal conditions
- Interpret
*Minimum Inhibitory Concentration
229
The LOWEST concentration of antibiotic that shows no growth is the ____
*MIC
230
Pros of ___:
- Quantitative rather than qualitative (you will know how much to give)
- Compare to dosage tolerated by pts
- Allows for anaerobes
- Can be automated
- The "gold standard" of antibiotic sensitivity test
*MIC
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Cons of ___:
- Requires more materials than KB
- More error prone if using separate tubes
*MIC
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- Some antimicrobials can be very ___ to humans.
| - Compare the toxic dose to the MIC to get ___.
* toxic
| * therapeutic index
233
toxic dose/MIC = TI
| -you want the TI to be high b/c:
*you would need a high amount of the drug to harm the pt
234
- inhibit peptidoglycan(cell walls)
- inhibit 70S ribosomes
- inhibit DNA
- inhibit folic acid synthesis
- destroy cell membrane(outer membrane of gram neg cell)
*Actions that antibiotics have on bacterial cells
235
___ antibiotics:
- penicillin(good for gram neg bac) and derivatives EX: ampicilli , methicillin is good for infections that resist penicillin
- cephalosporins(good for gram pos bac)
- carapenems(good for pneumonia)
- bacitracin: topical antibiotic, narrow to penicillin
- vancomycin: used for mersa, expensive and toxic on kidneys
*peptidoglycan antibiotics
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___ antobiotics:
- aminoglycosides: streptomycin-used for plaques and TB
- tetracyclines: doxycycline-used for lime disease and STI's, has a broad spectrum
glycylcyclines: tigecycline-used when resistance to doxy
- macrolides: erythromycin and azithromycin- zpac, used short term
- clindamycin: used when allergic to penicillin and leads to SUPER INFECTIONS
*protein synthesis antibiotics
237
___ antibiotics:
| -sulfonamides: sulfa and bactrim -can cause allergies and brain damage
*folic acid antibiotics
238
___ antibiotics:
- fluoroquinolones: ciprofloxacin - tx for gram pos that are resistant to other drugs used for UTI and anthrax
- rifamycin: ONLY effective on gram pos bac, used for TB
*DNA/RNA antibiotics
239
___ antibiotics:
| -polymyxins: polymyxin B - toxic to kidneys, used for UTI's that wont go away and pseudomonous s.
*call membrane antibiotics
240
- fungi and protozoans
- bacterial antibiotics often ineffective
- often hard to find something with appropriate selective toxcity
*treating eukaryotic infections
241
- macrolide polyenes
- azoles
- echinocandins
- flucytosine
are ____.
*antifungals
242
- bind to fungal membranes and they lose select permeability
- treats serious systemic infections (histoplasmosis fungal meningitis)
- amphotericin B: tx for histo fungal meningitis
*macrolide polyenes
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- interfere with sterol synthesis
- good for cutaneous/mucuccc membrane infections(thrush, vaginal yeast infections)
- EX: miconazole and ketoconazole
*azoles
244
- inhibit cell wall synthesis
- candida and aspergillosis
- micafungin and capsofungin
*enchiocandins
245
- rapid absorption(oral) and dissolution into fluids
- treat cutaneous mycoses
- usually combine with other drugs (resistance issues)
*flucytosine
246
- quinines and quinoiones
- flagyl (metronidazole): treats gardia, trich vaginalis
- some other antibiotics useful:
- quinacrine
- sulfonamides
- tetracyclines
*antiprotozoans
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- synergy
- 10+10=30
- complex
- Ex: HIV
*drugs working together
248
- preventative
- Ex: invasive dental work, exposure
- we try to avoid this
*prophylactic antimicrobic
249
- drug cant get to the infection site b/c person may have impaired circulation or route of transmission
- resistance
- more than one pathogen is present(open wounds)
- adverse pt reaction
*Reasons why the drug did not work
250
When a drug was previously effective no longer is.
- mutants in genome
- can occur in any pathogen
*drug resistance
251
- prokaryotes mutate rapidly and often
- short generation
- pili (little tube that may transfer resistance)
*mutations in genome
252
- bacteria secretes new enzyme
- altered membrane receptors(bacteria changed locks)
- drug pumps(allows bacteria to pump out drug, multiply resistance)
- internal changes in pathogen(ribosomes in bacteria can change)
- change in pathogens metabolic pathway, bacteria may find alternate route.
*how resistance work
253
3 ways resistance can form:
- transformation
- transduction
- conjugation
254
-bacterial cell---lysis--information leaks out genetic information
*transformation
255
-bacterial phage can come in and give resistance
*transduction
256
-spreading by the pillies from bacteria to bacteria
*conjugation
257
- all populations have individual variation
- members in a population struggle to survive
- those with some selective advantage will survive
- survivors can pass on advantage. They will predominate
*natural selection
258
- take antibiotic for the time prescribed
- do not self prescribe
- take antibiotic as prescribed
- report adverse reactions immediately
- avoid antibiotics in food
- well managed multi drug therapy in NOT a problem
*prevention of resistance
259
3 adverse reactions:
- allergies
- toxicity
- superinfections
260
- A specific immune response to a foreign material.
- immediate hypersensitivity=rapid and extreme
- occurs after liver begins processing
- allergen is usually not the entire antibiotic
*allergy
261
3 outcomes of an allergic reaction:
- rash
- shock
- respiratory arrest
262
- vomiting
- headache
- nausea
are examples of ___
*intolerance
263
- liver and kidneys
- GI tract
- CNS
- endocrine system
- skin
*toxcity
264
- vancomycin: nephrotoxic
- gentamycin: GI track, 8th cranial nerve(hearing)
- amphotericin B: hepatatoxic
- metronidazole: hard on GI track
*toxic drugs
265
- understand risks of drug
| - peak and trough levels
*managing toxicity
266
Pt is ordered drug X to be administered via IV drip over 90min. After 72 hrs, peak/trough levels are ordered.
- up to 30min before next dose, draw through(lowest) level blood(1 serum tube). Hang the antibiotic.
- up to 60min after the dose has finished transfusing,draw the peak(highest) level blood(1serum tube).
*peak and trough levels
267
What does the peak and trough levels tell us:
*how quickly the liver and kidneys are clearing the drug
268
-Antibiotics may kill the good ones and let bad ones take hold
-often occurs after long term antibiotic therapy especially with broad spedifictrum antibiotics
Ex: c.dificile afterf clindamycin tx
lactobacillus killed off in the vagina
*superinfection
269
Possible solutions to superinfection:
* probiotics
* prebiotics
* transplant
270
In yogurt, puts bacteria back in system
*probiotics
271
Feeding bacteria so they can grow
*prebiotics
272
Fecal transplants by enema
*transplant
273
- target iron scavenging by bacteria
- RNA interference (RNA)
- mimicking defenses peptides
- using bacteriophages
*new approaches for superinfections
