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Microbiology Flashcards

1
Q

Cell wall: proks, euks, virus

A

Proks: all except mycoplasma
Euks: only fungi and algae
Virus: no

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2
Q

Cytoplasmic membrane: proks, euks, virus

A

Proks: no sterols (except mycoplasma)
Euks: sterols
Virus: none (some with lipid coat)

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3
Q

DNA/RNA: proks, euks, virus

A

Proks: SS DNA, single, no proteins
Euks: >1 chromosome, proteins
Virus: SS, DS, DNA/RNA, some enzymes

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4
Q

Ribosomes: proks, euks, virus

A

Proks: yes
Euks: yes
Virus: no

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5
Q

Respiration: proks, euks, virus

A

Proks: cell membrane
Euks: mitochondria
Virus: none

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6
Q

Reproduction: proks, euks, virus

A

Proks: asexual (binary fission)
Euks: sexual + asexual
Virus: asexual

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7
Q

What prokaryote requires a living host?

A

Ricketsia

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8
Q

What prokaryote doesn’t have a cell wall, but contains sterols?

A

Mycoplasma

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9
Q

Which eukaryotes have cell walls?

A

Fungi + Algae

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10
Q

What are 3 factors that influence pathogenesis?

A
  1. Tissue tropism
  2. Host immune response
  3. Secondary replication sites (virus)
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11
Q

What are innate defenses of: eye, resp, GIT, skin, UG?

A

Eye: blinking, tears, lysozyme
Resp: mucus, cilia, phags, lysozyme, cough/sneeze
GIT: pH, flora, peristalsis, GALT
Skin: lactic acid, proprionic acid, lysozyme, flora
UG: urine, acidity/lavage, lysozyme, vag acid, flora

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12
Q

Differentiate between endogenous and exogenous microbes.

A

Endogenous: in/on the body (skin microbes: cut–>deeper)
Exogenous: encounters with microbes in the environment (ingress-on epi surface vs. penetration-within fluid/tissue)

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13
Q

Differentiate between ingress and penetration w/ respect to exogenous microbes

A

Ingress: ex/ inhalation, ingestion (surface of epithelium)
Penetration: ex/wound, insect bite (deep to epidermis – within tissue or fluid)
Sexual can be both

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14
Q

Differentiate between infection and intoxication.

A

Infection: microbe completes all steps of pathogenesis and multiplies
Intoxication: damage caused by toxin; NO multiplication of microbe

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15
Q

Which bacteria do not have a cell wall?

A

Mycoplasma

Ureaplasma

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16
Q

Which bacteria have a flexible cell wall?

A

Borrelia
Leptospira
Treponema

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17
Q

Which bacteria have a filamentous, rigid cell wall?

A

Actinomyces
Mycobacterium
Nocardia

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18
Q

Which bacteria have a simple cell wall, but are obligate intracellular?

A

Chlamydia/Chlamydophilia
Rickettsia
Ehrlichia

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19
Q

Which are the gram-positive bacteria?

A

Cocci: staphylo, strepto, entero
Bacilli: bacillus, clostridum, cornybact, lactobacilli, listeria, propionibact

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20
Q

Which are the gram-negative bacteria?

A

Cocci: moraxella
Non-enteric bacilli: bartonella, bordetella, brucella, burkholderia, francisella, haemophilis, legionella, pseudomonas
Enteric bacilli: campylobacter, enterobacter, eschericia, helicobacter, klebsiella, proteus, salmonella, shigella, vibrio, yersinia

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21
Q

Define and give examples of the following coccus terms:

Single
Pair
Chain
Cluster
Tetrad
A 
Single: no example
Pair: streptococcus pneumonia
Chain: streptococcus pyogenes
Clusters: all staphylo
Tetrad: sarcinia
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22
Q

List all 4 gram-staining steps

A
  1. Crystal violet
  2. Gram’s iodine
  3. Decolorizer (organic solvent)
  4. Safranin
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23
Q

For which bacteria is it appropriate to do an acid-fast stain?

A

Gram’s resistant bacteria

  • Mycobacterium
  • Nocardia
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24
Q

What color are acid-fast bacteria vs. non acid-fast bacteria?

A

Acid-fast: red/pink

Non-acid-fast: blue/green

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25
What are the major internal, cell envelope, and external structures of a prokaryote?
Internal: cytosol, nucleoid, ribosomes Cell envelope: glycocalyx, cell wall, cell membrane External: flagella, pili, fimbrae, endospores
26
What do bacterial chromosomes have that serve a function like histones?
Mg2+ ions
27
Are bacterial chromosomes DS, SS, circular, linear, 1 or 2 chromosomes? Are there any exceptions
SS, circular, 1 chromosome Linear: streptomyces, borrelia 2 chromosomes: rhodobacter sphaeroides
28
What am I describing: >=1 virulence genes, large genomic area, located next to tRNA, associated with transposons, unstable
Pathogenicity islands
29
What is a plasmid? Describe 4 key features.
Extra-chromosomal, circular, self-replicating DNA * Abx resistance (R plasmid) * Tolerance to metals * Production toxins * Mating capabilities (F plasmid)
30
R plasmid | F plasmid
R: abx resistance F: mating
31
What percentage of cell membrane is phospholipid vs. protein?
Phospholipid: 20-40% Protein: 60%
32
What is the function of the periplasmic space?
Nutrient transport, nutrient axquisition, detox (beta-lactamases), membrane derived oligosaccharides, osmoprotectants
33
What is the mesosome?
Present in mostly gram+ bacteria; extensive invagination associated with the nucleoid/cell replication
34
Describe bacterial ribosomes
70s, 50s-23s, 5s, 30s-16s 60% RNA 40% protein
35
What are endoflagella?
Axial filaments in spirochetes bacteria that are anchored at the end of a cell causing rotation and movement of the cell (in periplasmic space)
36
What connects NAM-NAG?
Beta-1,4 glycosidic linkages
37
What is the Schwartzman reaction?
Dermal necrosis caused by lipotechoic acid in gram + bacteria
38
Gram positive bacteria cell wall contains
Lipoteichoic acid, teichoic acid
39
Gram negative bacteria cell wall contains
LPS, LP (Lipid A anchored to cell membrane)
40
Gram-negative bacteria have endotoxin/exotoxin?
Endotoxin
41
Acid-fast bacteria do no gram-stain because they have...
Waxy mycolic acids that resists gram stain (arabinogalactan esterification)
42
Lysozyme
Breaks beta-1,4 linkages between NAM-NAG
43
Spheroplast/Protoplast | Gram + / Gram -
Protoplast: gram positive -- entire cell wall is destroyed Spheroplast: gram negative -- only part of cell wall is destroyed
44
Penicillin...
Binds to penicillin-binding proteins (PBP) transpeptidases that inhibits the formation of NEW cross-linkages in the cell wall
45
K, M, V antigen
K: capsule M: streptococcus pyogenes V: salmonella
46
Describe some functions of the glycocalyx
Adherence to surfaces, antigenic activity, anti-phagocytic, prevention neutrophil killing bacteria, prevention PMN leukocyte migration, toxicity, protection
47
What is the Quellung reaction?
Swelling reaction-- determines capsule presence by microscopy - Anti-serum+bacteria--> swelling - Typing!
48
Do cocci have flagella?
No
49
Are flagella essential for survival?
No
50
Is hemorrhagic necrosis more likely with gram positive or negative bacteria?
Negative
51
What are the various polar/lateral arrangements of flagellum?
Polar: monotrichous, amphi (bi-polar), lopho Lateral: petri
52
Differentiate between basal bodies of gram positive and gram negative bacteria.
2 rings - gram + (S+M) | 4 rings - gram - (S+M+L+P)
53
What are the 3 components of flagella?
1. helical filament 2. hook 3. basal body
54
What is H antigen?
Helical filament antigen (H-german word for hot condensation on a cold window)
55
Differentiate between positive and negative chemotaxis.
Positive: up [ ] gradient Negative: down [ ] gradient
56
Who has a pilus: gram+ or gram-. What is a pilus? What is it composed of?
Gram- only | *Entry of genetic material during conjugation; composed of the protein: pilin
57
What is the role of fimbrae?
Attachment and adhesion to eukaryotic cells, predominately gram-
58
They glycocalyx has this layer, which can often adhere to surfaces, i.e. plastics. What bacteria often colonize?
Slime layer, i.e. Staphylococus epidermidis
59
What 2 bacteria produce endospores?
Bacillus, clostridium
60
T/F Endospores are highly resistant.
True!
61
Where does one find calcium-diplcolonic acid?
Within the endospore core
62
What makes endospores so resistant?
Coat: keratine-like, impermeable Cortex: PG, few X-links Spore wall: PG; cell wall germinating Core: genetic material, energy, protein synthesis, calcium-dipicolinic acid
63
Differentiate between CCW/CW bacterial/flagella movement.
CCW: smooth swimming CW: tumbling (turning)
64
Differentiate between sporulation and germination
Sporulation: unfavorable growth conditions Germination: favorable growth conditions
65
In bacteria, who codes for virulence factors?
Plasmid
66
Mycoplasma are resistant to:
1. Lysozyme 2. Penicillin 3. Cycloserine
67
How does mycoplasma reproduce?
Cytoplasmic replication lags behind DNA replication
68
Who is the smallest organism capable of reproduction?
Mycoplasma
69
How does mycoplasma grow on media? Is there an exception?
Grows diphasic colonies | * Except M. pneumoniae
70
What is special about mycoplasma's attachement organelles?
1. Tapered tip 2. P1 adhesin * Surface epithelial cells
71
T/F Rickettsiaecease are cultivated on agar.
F: obligate intracellular pathogens
72
T/F Rickettsiaecease are zoonotic (arthropod vector)
True
73
What do rickettsiaecase have in their cell walls?
Diaminopimelic acid
74
Differentiate between the elementary body and the reticulate body of chlamydiaceae.
EB: infectious, non-replicative, adapted for EC survival, metabolically inactive RB: non-infectious, replicative, IC survival, met active
75
T/F All obligate intracellular bacteria are zoonotic.
True
76
Define the following terms: Symbiont Commensal Parasite
S: both benefit C: one benefits P: one benefits, one harmed
77
Mould vs. Yeast: uni/multicellular, hyphae, a/sexual reproduction
Mould: multicellular, hyphae, a/sexual reproduction (spores)
78
Differentiate between septate and aseptate fungi
Septate: separated, multinuclei Aseptate: non-separated, multinuclei
79
What is a mycelium? What does it consist of?
Intertwined mat of hyphae | 2 portions: vegetative and reproductive (spores)
80
What are dimorphic fungi?
Same organism exhibits 2 different forms -- mould and yeast
81
Are fungi more likely to be yeast or mould at physiological temperature?
Yeast
82
Which fungi exist solely as yeast and solely as mycelial?
Yeast: torula Mycelial: Aspergillus
83
Fungi appear gram + or -
+
84
What does fungal staining tell us?
1. Yeast vs. mould 2. Hyphae (septate/non-septate) 3. Spores (thallospores or sporangium)
85
Which fungus has a capsule?
Cryptococcus neoformans
86
T/F You can use the India ink stain for fungi
True
87
What is a fungal cell wall made of?
Chitin | * N-acetyl-D-glucosamine
88
T/F Fungal cell walls have beta-1,4 glycosidic linkages
True
89
T/F Fungal cell membranes contain this type of sterol
Ergosterol
90
Fungi are haploid/diploid
Haploid
91
T/F Fungi have toxins
True
92
Bacterial cell replication is called...
Binary fission
93
T/F Bacterial growth is constant
True, exponential
94
How do yeast replicate?
Budding (asexual)
95
How do moulds replicate?
Sex + Asex
96
Define: psychrophilic, psychotroph (fac psychrophile), mesophile, thermophile
Psychro: 20 Meso: 20-40 Thermo: >45
97
Define optimal temperatures for different types of fungi.
Mold: sub-physio (dimorphic) Yeast: physio
98
What two enzymes are necessary to remove harmful ROS?
1. SOD (O2- + H+ --> H2O2 + O2) | 2. Catalase (H2O2--> H2O + O2)
99
Determine the presence of SOD & catalase for obligate aerobes, microaerophiles, obligate anerobes, fac anareobes
OA+FAn: SOD+Catalase Micro: SOD Obligate an: none
100
Mold/yeast -- O2 requirements
Mold: aerobes Yeast: fac anaerobes
101
Absorption and solution factors inc/dec Aw
Dec
102
What is a halophile
Salt-tolerant bacteria -- low Aw
103
What is the Aw of sea water?
0.98
104
Xerotolerant microbes can survive below this Aw...
0.6
105
Differentiate between lithotrophs and organotrophs.
Litho: inorganic H/electron source Organo: organic
106
Most pathogens are: auto/hetero-troph, photo/chemo-troph, litho/organo-troph
Hetero, chemo, organo
107
Differentiate between known/unknown laboratory media
Known: 100% known Unknown: < 100% known
108
Define these 4 types of media: all purpose, enriched, reduced, transport, selective, differential
Enriched: basal support + nurtient supplement (blood agar) Reduced: addition of reducing agent to remove oxygen Transport: preserve in transit Selective: allows 1 species to grow and suppresses others (C-energy, pH, O2) Differential: More than 1 grow, but visible change in agar
109
How do you culture and plate fungi?
1. Primary -- selective isolation / sabouraud's agar, with abx to prevent bacteria 2. Secondary -- culture & ID -- incubate at 25C
110
Define biocides.
Physical (temp) or chemical (disinfectant, antiseptic, antibiotic) agents to control growth of microorganisms.
111
Is sterilization an all or none phenomenon?
Yes
112
Differentiate between "-static" & "-cidal"
- static: stop growth | - cidal: kill
113
Order from sensitive to resistant: prion, large non-enveloped virus, small non-enveloped virus, enveloped virus
Sensitive-----> Resistant | Enveloped virus, large non-enveloped, small non-enveloped, prions
114
What are the factors influencing choice of antimicrobial and outcome of treatment?
1. Number and type of organism 2. Presence of organic material (pus) 3. Type of microbe/type of material/surface
115
What is preferred for sterilization: moist or dry heat?
Dry
116
Differentiate between anti-septic and anti-biotic
Anti-septic: on living surface | Anti-biotic: anti-microbe
117
What is an autoclave?
Dry heat (121 celsius) under pressure (2 atm)
118
Why might you choose to use ethylene oxide rather than an autoclave?
Heat sensitive material (i.e. plastic, suture, bone graft, heart valve)
119
What is ethylene oxide?
Physical control of microbial growth | *Strong alkylator, cause mispairing of bases (reacts with guanine of DNA/protein) and halts metabolism
120
What is the most difficult microorganism to kill?
Bacterial spores
121
What is a key characteristic of antiseptics?
No toxicity of human tissue
122
Order the following disinfectants from high risk to low risk: gluteraldehyde, peracetic acid, etoh, iodophor, surfactant
``` Gluteraldehyde -- cross-linking Peracetic acid -- oxidizing agent ETOH -- Protein denaturation and coagulation Iodophor -- oxidizing agent Surfactant -- surfactant ```
123
Among the following, which have the greatest effects as anti-septics? ETOH, clorhexidine, iodine, triclosan
ETOH = iodine >> clorhexidine > triclosan
124
What is the difference between narrow and broad spectrum antibiotics? Give an example of each.
Narrow: limited number of species (Flagyl -- anerobes) Broad: many species (aminoglycosides -- gram+ and gram-)
125
What is the ideal feature of an antibiotic?
Targets something unique to the infecting microorganism and not toxic to the host
126
What are key considerations to take into account when using an anti-microbial agent?
Immune status of patient, degree of penetration (CSF, bone), combo therapy (potential for resistance), local environment (pH, O2), sensitivity of organism
127
What are the 4 major classes of antibiotics & examples of each class?
1. Cell wall-Penicillin (beta-lactam), cephalosporin, glycopeptides (vanc), carbapenem, cycloserine 2. DNA/RNA- DNA- clofazimine, metronidazole, quinoline; RNA- Rifampin, rifabutin 3. Protein- 30s (aminoglycosides, tetracyclin)/50s 4. Metabolism - sulfonamide, trimethoprim, Para-aminosalicylic acid
128
What are the 4 major mechanisms of antibiotic resistance?
1. Permeability barriers -- i.e. gram - 2. Efflux pump 3. Antibiotic target modification -- i.e. MRSA 4. Inactivating enzymes -- i.e beta-lactamase
129
How can you overcome beta-lactamase?
Use combination therapy of a beta-lactam and a beta-lactamase inhibitor (i.e. clavulanic acid)
130
What is clavulanic acid?
Beta-lactamase inhibitor
131
What are the 4 major genetic mechanisms for the acquisition and transfer of antibiotic resistance genes?
1. Plasmid: conjugation 2. Loose DNA: transformation 3. Bacteriophage: transduction 4. Transposon: transposition
132
How would you define recombination (with respect to bacterial antibiotic resistance?)
Stable maintenance, incorporation into the chromosome (breaking and joining DNAD into new combinations)
133
Differentiate between homologous and non-homologous recombination.
Homologous: conjugation, transformation, transduction | Non-homologous: transposition (cut and paste)
134
What is high frequency recombination?
Complete transfer of F plasmid and its integration into the chromosome
135
When would a bacterial cell acquire free floating DNA in the environment? What is this called?
Cell death; transformation
136
What is special about DNA binding proteins in bacterial recombination?
Transformation; will discriminate which species DNA to accept
137
Give 3 examples of bacteria that undergo transformation.
1. Haemophilus 2. Streptococci 3. Neisseria
138
What are the two major types of bacterial transduction?
1. Lytic/virulent/generalized | 2. Temperate/Specialized (lysogeny -- bact carrying a prophage)
139
What is Lysogeny?
When bacteria are carrying a prophage
140
What are the limits on the use of each of the following drugs: aminoglycocide, glycoprotein, nitroimidazole, penicillin, cephalosporin
``` NOT effective against: Amino: anaerobes Glycoproteins: gram negative Nitroimidazole: aerobes Penicillin: mycoplasma Cephalosporin: mycobacteria ```
141
Describe the mode of action of the bacterial protein synthesis inhibitors.
30s: amino/misreading DNA; tetracycline-block 50s: macrolide (transpeptidation and translocation), lincosamide (block binding at A/P sites), streptogramins (inhibit peptide bond formation)
142
Aminoglycocides vs. Tetracycline
Amino: cidal -- misreading bases Tetra: static -- block tRNA binding
143
Describe the various generations of the penicillins.
1st: natty, Pen G 2nd: methicillin (penicillinase-resistant) 3rd: aminopenicillin - ampicillin (resist low pH) 4th: extended spectrum (gram +/-); peperacillin
144
What are the 4 categories of antifungals?
1. Direct membrane damage (polyenes, i.e. Ampho B) 2. Nucleic acid syn (flucytosine) 3. Cell membrane/ergosterol (azoles, allylamines) 4. Cell wall/ beta-d-glucan + chitin (echinocandins, nukkomycin)
145
For which fungal infections is echinocandins indicated?
Candida and Aspergillus, not C. neoformans
146
Describe where the following bacteria tend to colonize: | S. mutans, S. salivarius, Campylobacter, N. gonorrhoae, B. pertussis, S. aureus
``` S. mutans - enamel S. salivarius - tongue epi Campylobacter - intestinal mucosa N. gonorrhoeae - uretheral epithelium B. pertussis - upper RTI S. aureus - nasal mucosa ```
147
Fimbriae are characteristic of gram + or -
Negative
148
Give an example of afimbrial adhesin that is a virulence factor.
B. pertussis ligand -- filamentous hemagglutinin (FHA) | Prevention: FHA vaccine
149
Is invasion necessary for all bacteria? Why
No; toxins (i.e. diptheria)
150
What are the 6 steps of bacterial pathogenesis?
1. Exposure/Entry 2. Attachment 3. Invasion 4. Evasion immune response 5. Effects on host 6. Dissemination/shedding
151
How can bacteria and fungi make their way into non-phagocytic cells? Give 2 examples.
Use of invasins/host cell cytoskeletal re-arrangement (i.e. membrane shuffling) 1. L. monocyotgenes (internalin A) 2. Shigella
152
What are the 3 possible consequences of bacterial invasion?
1. Restricted to the site of entry 2. Spread to immediate underlying tissue, no further dissemination 3. Spread to other body sites (dissemination)
153
What are 3 bacterial dissemination enzymes?
1. Hyaluronase 2. Streptokinase 3. Collagenase
154
How do bacteria evade complement, phagocytosis, antibodies?
Complement: capsule, binding proteins, proteases, host cell mimicry Phag: capsules, intracellular parasitism Ab: MHC presentation/Ag-variation, Ig-inactivation
155
What is one example of bacterial host cell mimicry?
Use of a hyaluronic acid capsule
156
Is cryptococcus neoformans encapsulated?
Yes
157
How does the body overcome encapsulated bacteria that need to be phagocytosed?
Opsonization -- IgG, C3b
158
How can bacteria evade complement and phagocytosis without the use of capsules?
``` Elastase (Pseudomonas aeruginosa) -- inactivate C3b, C5a C5a peptidase (S. pyogenes) -- inhibit phagocyte chemotaxis, degrade C5a ```
159
How can bacteria evade macrophages and leukocytes?
Leukocidins -- ADP-ribsolyaltion of protein controlling phosphatidylinositol (disruption of cellular activities)
160
What are the 4 possible outcomes of infection on the host?
1. Infection/Damage 2. Permanent relationship 3. Subclinical 4. Prevention/clearance
161
Differentiate between endo and exotoxins
Endo: high does, systemic, LPS, no toxioid, fever, cell lysis
162
Differentiate between AB & A5B stucture.
AB: covalent, single gene single peptide, post-translationally modified to A/B fragments, diptheria A5B: non-covalent, two genes encode for A/B subunits, cholera
163
Zinc metalloendoprotease
Proteolytic cleavage of toxin; 2 linked fragments * LC (enzymatically active), HC (binding/translocation) - --- Tetanus, Botox
164
ADP-ribosylator toxins
Diptheria, cholera
165
What are the 3 major components of a virus?
1. Core with nucleic acid/protein 2. Capsid 3. Envelope
166
What is the viral capsid? What are the 2 major capsid shapes?
Protection, nucleocapsid = protein shell * Proteins aggregate into capsomers 1. Helical 2. Icosahedral
167
What is the viral envelope?
Surrounds nucleocapsid "Shrink wrapped" 2 lipid bilayers interspersed with proteins * Material from host and virus
168
What are the 3 major types of viral proteins?
1. Nucleo-proteins: replication 2. Matrix proteins: links envelope and capside 3. Surface proteins: glycoproteins
169
The H. influenza virus has these 2 surface glycoproteins.
Hemagglutinin: attaches to sialic acid Neuraminidase: aids in viral release
170
How are viruses classified?
NA, symmetry, envelope, size
171
What is a bacteriophage? Majority are ss/ds RNA/DNA?
DS DNA | * Virus of bacteria
172
What are the 3 major mechanisms of viral detection?
1. Biochemical (enzymes, PCR) 2. Serological (ELISA, etc.) 3. Electron microscopy
173
The plaque assay for viral detection detects active/inactive/all virus?
Active
174
What is a defective virus?
Complete virus particle, unable to replicate without helper virus
175
What is a pseudovirus?
Non-viral DNA; infectious, cannot replicate
176
What is a viriod? What is an example?
infectious, sub-viral, small circular SS RNA genome, i.e. Hep D (within Hep B)
177
The name for a complete infectious viral particle
Virion
178
Differentiate between structural and non-structural viral proteins.
Structural: packaged in mature virus | Non-structural: not packaged
179
Every virus must be able to produce _____________ which can be recognized by cellular ribosomoes.
mRNA
180
What are the 5 steps of the viral life cycle?
1. Attachment (adsorption) 2. Penetration (injection) 3. Protein/Nucleic acid synthesis 4. Assembly/packaging 5. Virion release
181
What are the 3 major phases of the viral life cycle (not the 5 actual steps)
Eclipse - undetectable Maturation Latent - progeny accumulates in cell; ends when free virus is released
182
How do most viruses gain entry into a host?
Respiratory mucosa
183
Are helical viruses enveloped?
Yes
184
What are the 3 major things that determine the severity of a viral infection?
1. Nature virus 2. Site of infection 3. Immune status of patient
185
Differentiate between macule, papule, nodule, vesicular.
Macule: flat, colored Papule: slightly raised Nodule: larger raised Vesicular: blisters
186
What is epidermodysplasia verruciformis?
Rare inherited disorder that predisposes patients to widespread HPV & cutaneous sq. cell ca (think: tree man)
187
What is an example of an oral/respiratory tract viral infection?
Influenza
188
What is an example of a GIT viral infection?
Rotavirus
189
What is an example of viral induced skin disease?
HPV
190
HHV-5, aka ________ causes chorioretinitis in newborns.
CMV
191
EBV is HHV__
HHV-4
192
EBV is associated with these 3 cancers.
1. Nasopharyngeal 2. Burkitt's lymphoma 3. Hodgkin's lymphoma
193
HHV-8
Kaposi's sarcoma
194
HHV-4 | HHV-8
4: EBV 8: KS
195
Merkel cell polyomavirus is associated with...
Merkel cell carcinoma, a highly aggressive neuroendocrine carcinoma of the skin with high propensity of recurrence and mets
196
HBV, HCV; DNA, RNA
HBV: DNA HCV: RNA
197
What are the possible outcomes following HCV infection?
Recovery, Rapid cirrhosis, Chronic infection
198
HTLV-1 is associated with...
Adult T cell lymphocytic leukemia + spastic paraparesis myelopathy
199
The 3 viruses that may increase one's risk of developing non-Hodgkin's lymphoma.
1. HCV 2. EBV 3. HTLV-1
200
JCV virus is associated with
glioma
201
Describe the transformative capacity of the HPV virus
E6, E7 targets p53 & Rb; hence leading to hyper-proliferation
202
Who are the facultative intracellular bacteria?
Some nasty bugs may live facultatively | Salmonella, Neisseria, Brucella, Mycobacterium, Listeria, Francisella, Legionella, Yersinia
203
What is the quellung reaction?
If bacteria are encapsulated, capsules will swell when specific anticapsular antisera are added
204
What is special about M protein of S. pyogenes?
Can mimic heart tissue, so that when the immune system makes anti-protein M-Ab, it can target the normal heart tissue *rheumatic fever
205
For what 3 conditions can a single positive antibody be allowed for a confirmatory diagnosis?
Lyme, HIV, Hep
206
In an uninfected baby, IgM is present/absent and IgG rises/falls?
IgM absent | IgG falls every month
207
In an infected baby, IgM is present/absent and IgG rises/falls?
IgM present | IgG rises
208
Why would you draw a convalescent sample at 3-6 weeks?
To look for a 4-fold or greater increase in Ab response of IgG
209
What is special about haemophilus, anerobes in regular bottles and N. gonorrhea in joint fluid?
Require prompt culture
210
Differentiate between community-acquired diarrhea and inpatient diarrhea
``` Community = parasite, viral, shigella, salmonella, campylobacter Inpatient = C. diff ```
211
What is an example of an ESBL?
Klebsiella pnuemonia, E. coli
212
What is KPC?
Klebsielle pneumonia carbipenimase
213
What are 2 examples of highly resistant bacterial organisms?
Beta-lactamases, carbipenemiase
214
Most nosocomial infections become apparent after this time period
72 hours (3 days)
215
Environmental microbe cultures vary over time, but the nosocomial infection rate remains the same. What is the conclusion?
its the people and human practice!
216
What are the 4 major nosocomial infections?
UTI (catherter), pneumonia (VAP), SSI (hands, poor prophy), BSI (IV cath)
217
Droplets are greater than
5 microns in size
218
Who are the 4 major nosocomial microorganisms?
1. MRSA (Methicillin resistant s. aureus) 2. VRE (vanc. resistant enterococcus) 3. C. diff (intestinal) 4. Highly resistant negative rods (ESBL-enterobact, KPC-klebsiella, Acinetobacter-Iraq, Pseudomonas aeruginosa)
219
How is staph aureus spread?
By hand to an open wound
220
How can you reduce surgical site infections?
Pre-op prophy abx for qualifying surgery (dirty)
221
How have US hospitals attempted to lower MRSA?
**Universal pre-admission screening/weekly screening; Screen all high risk people upon admission (nare swab/culture/PCR); if +, place in isolation
222
Overuse of this antibiotic for the treatment of C. diff has led to the emergence of ______________ resistant organisms. The alternative is to treat with _____________________.
Vancomycin (C. diff) | ** Metronidazole
223
E. faecium is resistant to: (2 antibiotics)
Ampicillin, vancomycin
224
C. diff produces 2 toxins.
A: enterotoxin B: cytotoxin
225
C. diff can cause this severe complication with 30-80% mortality
Pseudomembranous colitis
226
Which kills spores: ETOH or soap/H2O
soap/H2O
227
Mandatory cleaning of rooms on enteric precautions with this product has helped lower infection rates.
Clorox
228
What are the 3 non-specific defenses of the upper-respiratory tract (not cilia).
1. sIgA 2. lactoferrin 3. lysozyme
229
What lasts long in the air: small droplets or dried droplets?
Dried
230
Differentiate between the upper and lower respiratory tracts.
Upper: nose --> bronchioles; ciliated pseduostrat, mucus, sec IgA, swallow + lysozyme (33-35 degrees); NORMAL flora Lower: sterile, non-ciliated, IgG, IgA, alveolar macrophages (37 degrees)
231
Describe the interplay between professional and secondary pathogens.
Epithelial damage, airway function altered, upregulation/exposure of receptors
232
Differentiate between antigenic drift & shift of the influenza virus.
Drift: gradual, loss of neutralizing Ab to H protein Shift: rapid, usually result of co-infection
233
Amantadine + Rimantadine
Influenza A only; M2 protein
234
Zanamivir + Oseltamvir (Tamiflu)
Influenza A+B; *N* only | - virus binds to its own sialic acid
235
What does not work in the treatment of the flu?
1. Post-exposure treatment | 2. Excessive antimicrobials --- drug-resistance
236
Differentiate between severity, animal reservoir, pandemic, epidemic, genetic changes for Influenza A, B, C
A: +++++ severe, animal reservoir, pandemic, S+D B: yes epidemic C: no epidemic
237
Measles and mumps are transmitted...
Respiratory
238
Antibodies are generated against H or N in influenza
H
239
Differentiate between teleomorphs and anamorphs.
Teleomorphs: can sexually reproduce Anamorphs: asexual reproduction
240
Ajellomyces is teleomorph/anamorph?
Teleomorph (Histoplasma, blastomyces)
241
Differentiate between H. capsulatum capsulatum/duboisii
Capsulatum: pulmonary/disseminated (E. US/LA), thin/small Dubois: skin/bone lesions, thicker walled, larger
242
``` Describe the following opportunistic fungal pathogens: Chemotherapy M. ventilation Malnutrition AIDS Neutropenic ```
``` Chemotherapy: Aspergillus, PCP M. ventilation: Aspergillus Malnutrition: CN, PCP AIDS: CN, PCP Neutropenic: Aspergillus ```

Term 4 (3 decks)

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