OVERVIEW OF THE METHODS AND STRATEGIES IN VIROLOGY Flashcards
(112 cards)
1
Q
viruses remain dormant until…
A
until they are attached to host cell where they use the machinery to produce virions
2
Q
father of virology
A
Dmitri Ivanowski
3
Q
isolated tobacco from the sap of diseased plants
A
Dmitri Ivanowski
4
Q
first identified the concept of vaccine
A
Edward Jenner
5
Q
work on rabies
A
Louis Pasteur
6
Q
discovered and coined the term bacteriophage
A
Felix D’Herelle
7
Q
discovered that yellow fever was caused by a virus and spread via mosquitos
A
Walter reed
8
Q
structural components of a virus
A
- nucleic acid
- capsid
- envelope
9
Q
dictates the shape of the virus
A
capsid
10
Q
basic unit of capsid
A
capsomeres
11
Q
virus envelope is composed of…
A
lipid layer that consists of glycoprotein and protein matrix
12
Q
function for viral entry to host cell
A
glycoprotein
13
Q
method of release for enveloped viruses
A
budding
14
Q
method of release for naked viruses
A
rupture or lysis
15
Q
smallest viruses
A
“Parvo no Pico”
Parvoviruses
Picornaviruses
16
Q
largest viruses
A
Poxviruses
Paramyxoviridae
Filoviridae
17
Q
the only virus that cannot be filtered due to its large size
A
Paramyxoviridae
18
Q
viruses with complex symmetry
A
Poxvirus (brick-shaped)
Bacteriophage (tad pole-shaped)
19
Q
viruses that require a helper virus
A
defective virus
20
Q
they only infect cells but is not capable of replication
A
pseudovirion
21
Q
synthetic viruses used to inject genetic material with specific traits into host cells
A
pseudovirion
22
Q
single circular RNA strand without capsid that causes plant disease
A
viroids
23
Q
infectious misfolded proteins that are abundant in neurons and most resistant to different agents
A
prions
24
Q
steps in viral replication
A
“APUSAR”:
1. adhesion
2. penetration
3. uncoating
4. synthesis
5. assembly
6. release
25
adhesion is also referred to as...
adsorption
26
three mechanisms of penetration
membrane fusion
synctia formation
receptor-mediated endomytosis (phagocytosis)
27
membrane fusion causes changes in cell membrane configuration causing it to become MORE POLAR which results to the...
synctia formation
28
this step is necessary to release the viral genome for delivery of the viral DNA or RNA to its intracellular site of replication
uncoating
29
uncoating is mediated by...
cellular enzymes
30
involves the production of nucleic acids and protein polymers
macromolecular synthesis
31
what is synthesized in the early stage of replication?
viral nucleic acid synthesis
32
what is synthesized in the late stage of replication?
viral protein synthesis
33
rapid identification of virus in a cell culture can be done by detecting ____________
early viral proteins
34
nonstructural elements produced during synthesis
early proteins
35
structural elements produced during synthesis
late proteins
36
staining technique used for rapid identification of virus in a cell culture but is less sensitive
immunofluorescent staining technique; detects early viral proteins in infected cells
37
newly formed nucleic acids are again enclosed by capsids
assembly
38
final step in viral assembly
acquisition of an envelope
39
at what viral replication stage does the inhibition of host cell DNA occur?
synthesis phase
40
morphologic changes in virally infected cells that are observed in the microscope
cytopathic effects
41
cellular changes during viral release
cell death/lysis, syncytia formation (giant multinucleated cells), inclusion body
formation or host cell transformation (WORST CELLULAR CHANGE).
42
glycoproteins produced by cells in response to Inducers
interferons
43
primary inducers of interferons
viruses
44
induces the formation of antiviral protein, alters cell's protein synthesis and inhibits viral replication
interferons
45
antiviral protein that degrades viral mRNA
synthetase
46
antiviral protein that inhibits protein synthesis
protein kinase
47
which nucleic acid is a better interferon inducer
RNA viruses are better interferon inducers than DNA viruses
48
interferons are _______-specific
a.) species-specific
b.) virus-specific
interferons are species-specific; not virus-specific
49
interferon secreted by lymphocytes; antiviral effect
interferon-alpha
50
interferon secreted by fibroblasts and macrophages; antiviral effect
interferon-beta
51
interferon secreted by T-lymphocytes; immunoregulatory effect
interferon-gamma
52
interferon/s with antiviral effect
interferon-alpha and interferon-beta
53
interferon/s with immunoregulatory effect
interferon-gamma
54
chemical agent that distinguishes enveloped viruses from naked viruses
ether
55
sensitive to ether
enveloped viruses
56
resistant to ether
naked viruses
57
destroys viral infectivity by reacting with nucleic acid
formaldehyde
58
more readily inactivated by formaldehyde
single-stranded genomes
59
less readily inactivated or resistant to formaldehyde
double-stranded genomes
60
inactivates and destroys the infectivity of virus
radiation
61
most radiosensitive property of virus
infectivity
62
all enveloped viruses are _____________ at 37ºC
heat labile
63
icosahedral-shaped viruses are ___________ at 37ºC
heat stable
64
___________ specimen collection is required because viruses may no longer be present within ____________________
early specimen collection is required because viruses may no longer be present within 2 days after first appearance of symptoms
65
viruses that require nasopharyngeal swab or aspirate specimens
Respiratory Syncytial Virus
Influenza
Parainfluenza
Rhinovirus
66
specimen for upper respiratory tract
nasopharyngeal swab or aspirate
67
viruses that require throat swab specimens
Enteroviruses
Adenovirus
Herpes Simplex Virus
68
specimen for posterior pharynx
throat swab
69
viruses that require bronchial/bronchioalveolar washing specimen
Influenza Virus
Adenovirus
70
specimen for lower respiratory tract
bronchial/bronchioalveolar washing
71
which viruses require stool and rectal swabs
Rotavirus
Enteric Adenoviruses
Enteroviruses
72
depth required for rectal swab
3-5 cm into rectum
73
stool required for examining virus
5-10 mL diarrheic stools
74
which viruses require urine as a specimen
CMV
Mumps
Measles
Rubella
Polyomavirus
Adenoviruses
75
how much urine specimen is required?
at least 10 mL and 2-3 specimens
76
viruses that require skin and mucous membrane lesion specimens
HSV
Varicella Zoster
Enteroviruses
77
viruses that require skin and mucous membrane lesion specimens
HSV
Varicella Zoster
Enteroviruses
78
specimen for vesicular lesions
skin and mucous membrane lesion
79
stains multinucleated giant cells in HSV and Varicella
Tzanck smear
80
specimen used primarily for the detection of CMV
blood
81
how much blood is required for the detection of CMV?
3-5mL of Anticoagulated Blood or 2mL for Pediatric Patients
82
specimen for Parvovirus B19
bone marrow
83
tissue biopsy is collected for viruses that infect the...
lungs, brain, and GIT
84
microscopy used in detecting characteristic appearance of virus particles
electron microscopy
85
when is acute serum collected?
collected ASAP after first appearance of symptoms
86
when is convalescent serum collected?
2-3 weeks after acute serum
87
indicates primary infection or recent infection
virus-specific IgM
88
indicates past infection or recent vaccination
virus-specific IgG
89
antibody titer results indicative of an active infection
fourfold or greater rise in antibody titer from acute serum and convalescent serum
90
most sensitive serologic test
ELISA or EIA
91
purpose of hemagglutination inhibition (HI test)
detection of viral antibodies
92
PMK
Primary Monkey Kidney Cells
93
HEK
Human Embryonic Kidney
94
HDF
Human Diploid Fibroblast
95
HEp-2
Human Epidermoid Cancer Cells
96
viral culture medium from cervical cancer cells
HeLa
97
viral culture medium from human embryonic lungs
MRC
98
Usually used for the DEFINITIVE DIAGNOSIS of viral infections however it takes a great deal of time and is hard to maintain integrity of viral samples
viral isolation or viral culture
99
true or false
specimens for culture should not stand at room temp or higher and should be stored on ice. if delay is unavoidable, refrigerate specimen.
truly...
100
usual specimen for viral isolation
anticoagulated blood in sterile tube
101
viral isolation: detection of virus in blood is best done by separating and culturing which cell?
white blood cells
102
medium used to separate WBCs from RBCs
Polymorphprep gel
103
reagents used in Polymorphprep gel
Sodium Metrizoate and Dextran
104
most preferred swab tips
dacron or rayon
105
most sensitive molecular test for the diagnosis of causative agents
PCR
106
detects viral DNA
PCR
107
most sensitive test for diagnosis
RT-PCR
108
detection of viral RNA
RT-PCR
109
means that symptoms are being treated not virus itself
symptomatic
110
Means that Treatment is just to Support Health of Patient like Hydration
supportive
110
Most Viral Infections:
________ onset,
_______ clinical course, and
_______ recovery
fast onset, brief clinical course and fast recovery
111
true or false
Most Viral Infections:
often get better in time as long as there is antiviral treatment
false.
MOST VIRAL INFECTIONS OFTEN GET BETTER IN TIME EVEN W/O ANTIVIRAL TREATMENT
