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Microbiology > Midterm 1 > Flashcards

Midterm 1 Flashcards

1
Q

MIC value

A

Minimal inhibitory concentration
= lowest conc. of antibiotics that are able to stop the growth of the bacteria

Determination:
Macro/micro/agar dilution, E-test

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2
Q

What can we use serological tests for?

A
  • Demonstration of diseases
  • Demonstration of previous diseases
  • Complete biochemical identification
  • Detection of pathogenic members of species
  • For getting data about spreading of serotypes
  • For epidemiological research
  • Detection of unknown antibody (by known antigen)
  • Detection of unknown antigen (by known antibody)
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3
Q

E-test

A

An elypsoid inhibition zone is made where the bacteria cannot grow.
The size of the zone indicates the MIC, and is measured by a band which starts at the onset point.

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4
Q

MBC value

A

Minimal bactericidal concentration

= lowest conc. of AB that kills the bacteria

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5
Q

What is serological tests and when is it good to use?

A
  • Laboratory tests with patient serum as specimen

- Good when cultivation takes too long, is dangerous etc

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6
Q

TORCH

A 
Tests for pregnant women
T: Toxoplasmosis
O: Other (syphilis, varicella-zoster, parvovirus B19)
R: Rubella
C: Cytomegalovirus (CMV)
H: Herpes genitalis (HH2) 
*Bad to find O and H, rest is good
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7
Q

Antigens on bacteria (4)

A

O antigen: cell wall
H antigen: flagella
K antigen: capsule
F antigen: fimbria

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8
Q

Weak antigens

A

Lipids

Polysaccharides

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9
Q

Strong antigens

A

Enzymes

Proteins

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10
Q

The complement system (where is it, how to inactivate, function)

A
  • Part of normal sera
  • Inactivated at 56 ‘C (30 min)
  • Make membrane complexes
  • Can cause lysis of cells (RBCs, bacteria)
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11
Q

Chemotherapic index

A

DTM/DCM

DTM: Dosis Tolereta Maxima = dose that host tolerate
DCM: Dosis Curativa Minima = min dose needed to cure

If values are close the AB is very toxic.

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12
Q

Classifications of serological tests

A
  • Qualitative (present/not)
  • Quantitative (amount)
  • Visible (agglutination, precipitation)
  • Invisible (IF, CFT, RIA, ELISA)
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13
Q

What is agglutination?

A

A reaction in which particles (as red blood cells or bacteria w/antigen on surface) suspended in a liquid collect into clumps and which occurs especially as a serologic response to a specific antibody (google definition)

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14
Q

Types of agglutinations

A
  • Slide agglutination (qualitative, if pos: white dots)
    Ag unknown, Ab known (specific sera, e.g O111)
  • Tube agglutination (quantitative, agglutination on bottom of tube, find titer*)
    Ag known, Ab unknown (dilution of patient sera)
  • Indirect agglutination (carrier - RBC, latex granule or S. aureus)
  • Titer: highest dilution fold (lowest Ab conc) where we can see agglutination
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15
Q

How the microbes act

A
  1. producing enzymes that destroy the AB
  2. developing a new structure of binding protein
  3. developing a new metabolic pathway, that bypass the reaction inhibited by the drug
  4. developing an altered enzyme, that can still perform its metabolic function, but is less affected by the drug
  5. elimination of the antibiotic by efflux pump
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16
Q

Hemagglutination

A

Indirect agglutination with RBC as carrier

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17
Q

Latexagglutination

- Good test for…

A

Indirect agglutination with latex granule as carrier

- Meningitis

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18
Q

Coagglutination

A

Indirect agglutination with S. aureus (prod. protein A - bind IgG) as carrier

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19
Q

Precipitation

A

Ag is SOLUBLE (enzyme, toxin, virus)

  • In fluid: ring precipitation
  • Agar: precipitation arch (e.g Elek test)
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20
Q

FOR PROKARYORIC CELL:

Main groups?
Size? 
Nucleus morphology?
Chromosomes?
Mitochondria?
A 
Groups: bacteria
Size: 0,5-20 micrometer
Nucleus: no membrane
Chromosomes: haploid
Mitochondria: absent
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21
Q

FOR EUKARYOTIC CELL:

Main groups?
Size?
Nucleus morphology?
Chromosomes?
Mitochondria?
A 
Groups: alga, fungi, protozoon, plant, animal
Size: >5 micrometers
Nucleus: wrapped with membrane
Chromosomes: diploid
Mitochondria: present
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22
Q

FOR PROKARYORIC CELL:

Ribosome units?
Sterol in cytoplasm membrane?
Cell wall constituents?
Reproduction?
Respiration?
A 
Ribosome units: 70S (50S + 30S)
Sterol in cytoplasm membrane: no
Cell wall constituents: peptidoglycan
Reproduction: binary fission
Respiration: by cytoplasm membrane
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23
Q

Why can penicillin be used for all non-allergi patients?

A

It inhibits the enzyme that makes pentaglycine cross bridges in peptidoglycans - a constituent ONLY found in prokaryotic cells (not human cells)

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24
Q

Essential components of bacterial cells?

A
  • Nucleus & ribosomes
  • Inner cytoplasm membrane
  • Cytoplasm
  • Periplasmic space
  • Cell wall

+ Outer membrane for gram neg. Bacteria

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25
Q

Accessory components of bacterial cell?

A
  • Plasmid
  • Spore
  • Capsule
  • Fimbria/pili
  • Flagella
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26
Q

FOR EUKARYOTIC CELL:

Ribosome units?
Sterol in cytoplasm membrane?
Cell wall constituents?
Reproduction?
Respiration?
A 
Ribosome units: 80S (60S + 40S)
Sterol in cytoplasm membrane: yes
Cell wall constituents: no cell wall/cell wall with chitin or cellulose
Reproduction: sexual, asexual
Respiration: by mitochondria
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27
Q

CYTOPLASM MEMBRANE:

Where?
Structure?
Function?

A
  • Between plasma and cell wall
  • Phospholipid bilayer
  • Selective permeability, transport process, glucose uptake, enzyme production, mezosome formation in gram pos. (helps DNA replication)
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28
Q

PERIPLASMIC SPACE:

Where?
Enzymes?
Properties?

A
  • Between inner cytoplasmic membrane and peptidoglycane
  • beta-lactamase, proteases
  • potential AND concentration gradient
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29
Q

CELL WALL:

Antigen?
Enzymes?
Made of?

A

Antigen: O
Enzymes: none
Made of: peptidoglycane

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30
Q

Third and fourth generation, Cefalosporins

A

Ceftazidime, Cefixime, Ceftibuten, Cefepime
good for treatment of meningitis
effective mainly against Gram negatives

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31
Q

G- cell wall

A

10-15 nm with 1-2 peptidoglycan layers

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32
Q

Peptidoglycane components

A
  • N-acetyl-glucose-amine
  • N-acetyl-muramic acids
  • Amino acids (D-conformation)
  • Techoic acid: antigen, lysozyme resistance
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33
Q

Pyrogenic risk of giving antibiotics?

A

Antibiotics release LPS (=endotoxin/pyrogenic material) -> fever -> ENDOTOXIC SHOCK (can kill patient)

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34
Q

OUTER MEMBRANE

Where?
What?
Function?
Important components?

A

Where: Gram negative bacteria
What: phospholipid bilayer
Function: defense against hydrolytic enzymes, contains receptors, uptake of vitamins and carbohydrates
Important components: LPS, endotoxin (lipidA)

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35
Q

DNA of bacterial nucleoid?

A

Double stranded

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36
Q

FLAGELLA:

Antigen?
Function?
Where?

A

Antigen: H
Function: movement
Where: anchored to cytoplasmic membrane

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37
Q

Example of bacterium with monotrichous flagella?

A

Pseudomonas aerginosa

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38
Q

Example of bacterium lofotrichous flagella?

A

Chromatium sp.

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39
Q

Example of bacterium with amphitrichous flagella?

A

Wolinella succinogenes

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40
Q

Example of bacterium with lofoamphitrichous flagella?

A

Halobacterium halobium

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41
Q

Example of bacterium with peritrichous flagella?

A

Escherichia coli

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42
Q

A) What is endoflagella?
B) Example of bacteria with endoflagella?
C) Function of endoflagella?

A

A) Flagella in cytoplasm
B) Spirochaetes
C) Bacteria can move easier in dense fluids

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43
Q

FIMBRIAE/PILI

Location?
No. of pili?
Types of pili?

Example of bacterium with pili?

A

Location: Anchored in outer membrane
No. of pili: 200-300
Types of pili: sex, common, adhesive

Example: Neisseria gonorrhoeae - allows it to attach to urethra

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44
Q

CAPSULE

Antigen?
Function?
Staining?

A

Antigen: K
Function: protects from phagocytosis
Staining: Negative with Indian ink

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45
Q

PLASMIDS

What?
Possible function?

A
  • Extra chromosomal elements, circular DNA, can be large

- May code resistance against antibiotics

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46
Q

Structure of spore?

A

DNA center with peptidoglycan and cytoplasmic membrane layers around and an endospore coat most externally

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47
Q

Example of coccus bacterium?

Coccus shape?

A
  • Micrococcus luteus

- Single cell

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48
Q

Example of diplococcus bacterium?

Diplooccus shape?

A
  • Neiserria gonorrhoeae

- Pair of cells

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49
Q

Example of streptococcus bacterium?

Streptococcus shape?

A
  • Streptococcus pyogenes

- Chain of cells

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50
Q

Example of staphylococcus bacterium?

Staphylococcus shape?

A
  • Staphylococcus aureus

- Cluster of cells

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51
Q

Example of tetragenus bacterium?

Tetragenus shape?

A
  • Planococcus

- Packets of 4 cells

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52
Q

Example of sarcinella bacerium?

Sarcinella shape?

A
  • Sarcina lutea

- Packets of 8, 16 or 32 cells

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53
Q

Example of V, X, Y shaped bacterium?

A

Cornybacterium

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54
Q

Example of bacillus?

Shape of bacillus?

A
  • Bacillus subtil

- Rod

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55
Q

Example of twisted bacterium?

A

Vibrio cholerae

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56
Q

Example of spirochetes?

A

Treponema pallidum

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57
Q

SIZE OF:

a) Spirochaetes
b) Bacilli
c) Coccobacilli
d) Cocci
e) Rickettsia

A

a) Spirochaetes: 4-30 micrometer
b) Bacilli: 5-10 micrometer
c) Coccobacilli: 1,5 micrometer
d) Cocci: 1 micrometer
e) Rickettsia: 0,5 micrometer

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58
Q

GRAM STAIN:

a) Color of gram positive - why?
b) Color of gram negative - why?
c) Color of intracellular bacteria - why?

A

a) Violet - more peptidoglycan layers = iodine-methylene complexes are trapped -> blue color is retained
b) Red - methylene blue color is lost because the peptidoglycane layer is so thin, the red is from safranine countercounterstaining (affects the gram positive as well, but it is a weak stain so not important)
c) Colorless

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59
Q

Gram positive bacteria: properties and constituents?

A
  • Thick cell wall
  • Often Teichoic acid
  • Sensitive to lysozyme
  • Sensitive to penicillin
  • Some strains have capsule
  • Some strains have spore formation
  • Some strains have exotoxin production
60
Q

Gram negative bacteria: properties and constituents?

A
  • Thin cell wall
  • Outer membrane
  • LPS
  • Endotoxin
  • Resistant to lysozyme
  • More resistant to penicillin than gram positive
  • Some strains have capsule
  • Some strains have exotoxin production
  • Never spore formation
61
Q

Elek test (use, Ag, Ab, pos. result)

A

For detection of toxin
- Ag: Corynebacterium culture
- Ab: Filter paper w/Ab against diphteria (antitoxin)
Pos result: Precipitation arch (if strain is toxin)

62
Q

Ring precipitation

A

-Quantitative
- Ag: soluble
- Ab: patient sera
Pos: Precipitation ring at meeting point (Ag+Ab)

63
Q

Elek test (use, Ag, Ab, pos. result)

A

For detection of toxin
- Ag: Corynebacterium culture
- Ab: Filter paper w/Ab against diphteria (antitoxin) - often from horse
Pos result: Precipitation arch (if strain is toxin)

64
Q

Quellung reaction

A

Ag: unknown (bacteria w/capsule)
Ab: Antibody produced against capsule
Pos: Capsule becomes opac and bigger

65
Q

Immobilization (Ag, Ab, pos)

A

Ag: Treponema pallidum
Ab: Patient sera
Complement
Pos: No motion, cells die by lyses (can be seen w/light microscope)

66
Q

Complement fixation test

A 
2 systems: 
1) Diagnostic system
- Ag: Known
- Ab: patient sera
- Complement
2) Indicator system
- Sheep RBCs
- Anti sheep RBC antibodies
If pos: Ag-Ab complexes formed, recognized by complement system, so when RBCs are added all of the complement system is "used up" -> NO lysis of RBCs

If neg: NO Ag-Ab complexes. When adding RBCs, complement system will attack them -> LYSIS

67
Q

If too much complement (complement fixation test)

A

False negative

68
Q

If too little complement (complement fixation test)

A

False positive

69
Q

ELISA

A

Ag: Known, artificial
Ab: unknown, patient sera
2nd Ab: antihuman globulin labelled with enzyme

If pos: Ab bind to Ag, 2nd Ab bind to Ab -> reaction when adding substrate (color)
EXCEPT: In competitive ELISA - less color when positive

70
Q

Immunofluorescent method (IF)

A

1) Direct
- Ag: unknown
- Ab: known, labeled with fluorescent dye (rhodanin, izothiocianat)
2) Indirect
- Ag: known
- Ab: unknown
- 2nd Ab: labeled antiglobulin

71
Q

Why is monitoring important?

A

Some antibiotics can be very toxic, and elimination through urine may cause kidney failure.
To determine the safe concentration it is necessary to produce a standard curve: diameter of inhibition zone vs. conc.

72
Q

When is MBC used?

A

Only in secere conditions like sepsis, oesteomyelitis, endocarditis and immuncomprised patients

73
Q

Conjugation method for gene transfer

A

By sex-pili (hair-like appendices on the surface of bacteria)
By plasmid - from donor to recipient
May occur intra or inter species

74
Q

Transduction gene transfer

A

by a bacteriophage

75
Q

Transformation gene transfer

A

uptake by “naked” DNA

76
Q

Synergistic antibiotics

A

2+3=8, one increases the effect of the other AB.

e.g.: Ampicillin and gentamicin

77
Q

Antagonistic ABs

A

2+3=1, one ABs decreases or inhibits the effect of the other
e.g.: ciprofloxcin and tetracycline

78
Q

DTM/DCM

A

max dose that host tolerate/ max dose needed to cure

If values are close it is very toxic.

79
Q

Dilution methods

A

Micro
Macro
Agar

80
Q

Diffusion methods

A

porous cup
bottomless cylinder
filter paper disk diffusion (Kirby-Bauer)
E-test

81
Q

Empirical therapy

A

Have to consider:
What the unknown causative agent might be
Knowing the natural resistance of the bacteria
Frequency of acquired resistance
Spectrum of an AB
Pharmacokinetics: conc., half-life, side effects

82
Q

How the microbes act

A
  1. producing enzymes that destroy the AB
  2. developing a new structure of binding protein
  3. developing a new metabolic pathway, that bypass the reaction inhibited by the drug
  4. developing an altered enzyme, that can still perform its metabolic function, but is less affected by the drug
  5. elimination of the antibiotic by efflux pump
83
Q

Difference between G+ and G- cell wall?

A

G+

  • many peptidoglycane layers (thick cell wall)
  • one single cytoplasmic membrane
  • stains blue with gram stain
  • often teichoic acid
  • sensitive to lysozyme

G-

  • 1-2 peptidoglycane layers (thin cell wall)
  • inner + outer cytoplasmic membrane
  • lipidA (endotoxin)
  • LPS
  • resistant to lysozyme
84
Q

Bacteria shapes

A
  • cocci: single cell
  • diplococci: par of cells
  • streptococcus: chain of cells
  • staphylococcus: cluster of cells
  • tetragenus: cells in 4
  • sarcinella: cells in 8, 16 or 32
  • V, X, Y shape
  • bacillus: rod
  • twisted shape: short spiral
  • spirochaetes: long spiral
85
Q

Cultivation

A

Def: to grow or raise (something) under conditions that you can control (google)

86
Q

Autotrophs

A

Synthesize organic nutrients themselves from inorganic compounds

  • Not pathogens
    1) Photoautotrophs - from photosynthesis
    2) Chemoautotrophs - from oxidation of inorganic substrate
87
Q

Heterotrophs

A

Require organic carbon for growth

  • Can be pathogens
    1) Paratrophs
88
Q

Paratrophs

A

Heterotrophs that only can multiply in living cells

89
Q

Sources of metabolic energy

A

1) Fermentation (Embden-Meyerhof pathway anaerobes)
2) Respiration (aerobes)
3) Photosynthesis (aerobes/anaerobes)

90
Q

Fermentation

A

Glucose -> Lactic acid + ATP + NADH2

  • Anaerobes
  • Lack catalase, peroxidase and superoxide dismutase
91
Q

Respiration

A

Glucose -> Pyruvate -> TCA cycle cytochromes -> ATP + CO2 + H2O2

  • Aerobes
  • Have catalase, peroxidase and superoxide dismutase
92
Q

Environmental factors affecting growth

A
  • Nutrients
  • pH
  • Temperature
  • Osmotic pressure
93
Q

Nutrients

A
  • Hydrogen
  • Carbon
  • Nitrogen (peptone, tryptone)
  • Minerals
  • Growth factors
  • Vitamins
94
Q

pH range for growth (+exceptions)

A
  1. 0-8.0 (7.4)
    - Vibrio cholerae: 8.5-9.0
    - Lactobacillus acidophilus: 5.0-5.5
95
Q

Psychrophilic

A

Temperature for growth: 15-20 ‘C

96
Q

Mesophilic

A

Temperature for growth: 30-37 ‘C

97
Q

Thermophilic

A

Temperature for growth: 50-60 ‘C

98
Q

Aeration

A

1) Obligate aerobes
2) Facultative aerobes
3) Microaerophils
4) Obligate anaerobes

99
Q

Obligate aerobes

A

O2 as hydrogen acceptor

100
Q

Facultative aerobes

A

Can live in presence of oxygen, but does not require it

Can use O2 and organic substances as hydrogen acceptor?

101
Q

Microaerophils

A

Requires lower O2 tension

102
Q

Obligate anaerobes

A

Use organic substances as hydrogen acceptor (requires O2-free environment)

103
Q

Gelatin

A
  • Polypeptide
  • Melting temp: 35 ‘C
  • Bacteria can use as nutrient
104
Q

Agar

A
  • Polysaccharide
  • Dissolves in water at 100 ‘C
  • Dissolves in gels at 38 ‘C
  • Melting temp: 50 ‘C
105
Q

Classification of culture media (by physical condition)

A

1) Liquid culture media
- Broth
- Synthetic broth
2) Solid culture media
- Liquid + 1-2 % agar or gelatin
3) Semisolid
- Between liquid and solid

106
Q

Classification of culture media (by solidifying form)

A

1) Agar plate
2) Slant agar (test tube med agar “på skrå”)
3) High agar (test tube med “rett” agar)

107
Q

Classification of culture media (by application)

A

1) Basic culture media
- Most bacteria can grow
- Plate with many cultures that look similar
2) Selective culture media
- Completely inhibit some kinds of growth by excluding critical nutrients or adding toxins
- Plate with few cultures that look similar
3) Differential culture media
- Uses differential marker (e.g color)
- Plate with many cultures that look different
4) Enriched culture media
- Contain growth factors + other organic substances (e.g blood, serum etc)

108
Q

Growth in nutrient rich environment (fluid)

A

“Planctonic growth”

- Floating around in fluid

109
Q

Growth in nutrient poor environment (fluid)

A

Form “biofilm” on surface

- This creates a nutrient trap and is also protective against phagocytosis

110
Q

Growth in solid medium

A

On surface of medion

111
Q

Advantages and disadvantages when starting treatment with the weaker ABs

A

Ad.:

  • It could be effective
  • Can keep the stronger one in reservoir

Disad.:

  • Delayed therapy
  • Prolonged recovery
  • Increases the possibility of cells to become resistant due to longer exposure to drug
112
Q

Advantages and disadvantages when starting treatment with the stronger ABs

A

Advantage:

  • Guarantee complete recovery
  • Shorten the recovery phase
  • Decrease the possibility for developing resistant cells

Disadvantage:

  • We use the most effective antibiotic needless
  • More side effects
113
Q

Why do we use antibiotics in combination?

A
  • to increase the antibacterial effect
  • to wide the antimicrobial spectrum – polimicrobial infections
  • to reduce the toxicity
  • to prevent selection of resistant cells
114
Q

Chemoprophylaxis

A

Administration of a medication for the purpose of preventing disease or infection

115
Q

Antibiogram

A

The sensitivity of a bacteria against antibiotics

116
Q

Mechanisms of action of AB

A
  • inhibition of cell wall synthesis
  • inhibition of protein synthesis
  • inhibition of nucleic acid synthesis
  • alteration the membrane permeability
117
Q

Inhibition of cell wall synthesis by penicillin

A

The penicillin contain ß-lactam ring
Bacteria containing ß-lactamase or secreting penicillinase, which destroy the penicillin molecule, is resistant to penicillin (staphylococcus, Neisseria, enteric bacteria=ESBL)
In other bacteria the penicillin will bind to the penicillin binding protein and inhibit the transpeptidase and activate autolytic enzymes

118
Q

Bacteria without cell wall

A

Mycoplasma

119
Q

What is MRSA, VRE, ESBL

A

Antibiotic resistant bacteria

meticilin resistant staphylococcus aureus
vancomycin resistant enterococci
extended spectrum beta-lactamase(s)

120
Q

Penicillinase (ß-lactamase) resistant Penicillins

A

methicillin, oxacillin, cloxacillin, nafcillin

121
Q

Cefalosporins, basic

A

7-amino-cefalosporicacid
mode of action: like penicillin
Spectrum: broad, bactericidal

122
Q

Cefalosporins, mechanism of resistance

A
  • penetration is difficult
  • lack of penicillin-binding protein
  • is broken down by ß-lactamase enzyme
123
Q

First generation, Cefalosporins

A

Cephalexin, Cefazolin

effective against: Gram positive cocci

124
Q

Second generation, Cefalosporins

A

Cefuroxime, Cefprozil, Cefaclor

effective against: Gram positive cocci and Gram negatives

125
Q

Third and fourth generation, Cefalosporins

A

Ceftazidime, Cefixime, Ceftibuten, Cefepime
good for treatment of meningitis
effective mainly against Gram negatives

126
Q

Sterilisation vs disinfection

A

sterilisation: killing all of organism

Disinfection: reduce the number of micro-organism present, but not destroy all

127
Q

Which type of bacteria can produce spores

A

gram positive

128
Q

Antiseptic agent

A

Local disinfectant,

disinfection of microorganism in non-living tissue, e.g skin

129
Q

Physical methods for sterilisation

A

Mechanical effects (hitting, pressure, sonification), considered as ineffective
Temperature: cold - ineffective, hot - most bacteria die at 60*C after 10 min.
Irradiation
Filtration
Centrifuge

130
Q

Chemical methods for sterilisation

A 
acids, alkali
alcohols
detergents
oxidative agents
heavy metals
phenol derivates
dyes
disinfectant gases
131
Q

Ethylene oxide

A

Flammable, toxic and strong mucosal irritant

Sterilisation at low temp.: 20-60*C

132
Q

What is autoclave?

A

Moist at 121*C and 1 atmosphere overpressure for 30 min –> temp is higher and penetration of steam is better
One of the best methods to kill bac

133
Q

Pasteurization

A

Using heat for disinfection

is not reliable, only the number of the cells is reduced
is used for heat sensitive materials (milk, beer)
slow: at 65C for 30 minutes
is quick: at 85C for 5 minutes

Ultra pasteurization: at 136*C for 1 minutes

134
Q

Disinfection methods

A

Heat: pasteurisation, steam, fractional heat treatment and boiling in water
Irradiation: UV light
Chemical agents: aldehydes, alcohols, phenols, halogens, oxidants, surfactants

135
Q

Anaerobic cultivations

A

1) Anaerostate
- Atmospheric air replaced with N2 and CO2 mix by a vacuum pump
2) Gas pack jar
- A plastic box where hydrogen is burnt in the presence of oxygen by catalysator
3) Anaerobic chamber

136
Q

Broth culture media (how to make)

A
  • Boil for 10-20 min

- Close by wax after inoculation

137
Q

High agar: can oxygen diffuse to bottom of agar?

A

No

138
Q

Fortner technique

A
  • Agar plate parted in two

- Streak on anaerobic bacteria on one side and aerobic bacteria on the other

139
Q

Blood culture (function, important in, incub. time)

A
  • For cultivation of blood or CSF
  • Important in: Meningitis, FUO
    - Also: endocarditis, bacteraemia, peritonitis
  • incubation time: 7-10 days (but most positives shows within 24 hrs)
140
Q

Important rules in blood culture

A
  • At least two samples from different part and different time
  • Vein cannula not allowed
  • Collection before fever
  • Sterility
  • Before antibiotic treatment
  • Aerobic or anerobic bottle
141
Q

Transport media

A

Stuart media:

  • Bacteria survive 48 hrs
  • Will not multiply!
  • Store at room temp
  • Good for both aerobes and anaerobes
142
Q

Transport culture media

A

Uriline, Uricult, Gonoline etc.

- Bacteria can multiply!

143
Q

Generation time

A

Time between two divisions (new generation)

- I mennesker er det 22-32 år fordi det er alderen hvor folk får barn

144
Q

Inoculation

A

The introduction of a pathogen or antigen into a living organism to stimulate the production of antibodies (definition google)

145
Q

Phases of bacterial growth curve

A

1) Lag phase (flat)
2) Log phase (increasing, growth)
3) Stationary phase (flat)
4) Death phase (decreasing)

146
Q

Counting bacterial cells

A

How many bacterial cells in 1 g or 1 ml

Methods:

  • By dilution
  • By filtration

Microbiology (1 decks)

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