Term
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Definition
-nonenveloped, icosadeltahedron w/ capsid (capsid-->viral attachment proteins)
-linear, dsDNA w/ 5' terminal proteins |
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Term
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Definition
1) viral attachment proteins promote internalization via receptor-mediated endocytosis
2) capsid delivers DNA to nucleus
3) early transcription=stim. cell growth
4) rep. of viral DNA
5) late transcription-->viral proteins
6) virions assemble in nucleus then released upon cell lysis |
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Term
| Adenoviruses pathogenesis |
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Definition
3 types of infections:
1) lytic- causes sx of disease
2) latent- asymptomatic, subject to reactivation (esp in lymphoid tissue)
3) transforming- change in morphology, biochemistry, or growth properties (only in rodents)
-infect epithelium (oropharynx, resp system, enteric organs
-penton base=inhibit mRNA transport and translation; cell rounding/tissue damage
-large intranuclear inclusion (sim. to CMV), cell necrosis, mononuclear infiltrates
-viremia + hematagenous spread esp in immunocomprised |
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Term
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Definition
-Ig formation- resolution of current infection and immunity to reinfection
-cell mediated immunity limits viral outgrowth |
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Term
| Adenoviruses virulence factors |
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Definition
1) virus-associated RNA's- post-translational gene silencing preventing activation IFN-induced protein kinase R mediated inhibition of viral protein synthesis
2) E3 and E1a block apoptosis
3) inhibit CD8 T cell MHC presentation |
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Term
| Adenoviruses Epidemiology |
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Definition
1) direct contact, fecal-oral, respiratory, waterborne (latter esp. in conjunctivitis)
2) childhood >>> adult infections
3) resp. disease common late winter-early summer |
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Term
| Adenoviruses Clinical syndromes |
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Definition
1) acute febrile pharyngitis +/- conjunctivitis (3-5 days)
2) acute resp disease
- military, 1-2 weeks
3) gastroenteritis/diarrhea
-serotypes 40-42 (enteric
adenoviruses), 1-2 weeks (long),
2nd leading cause of infant
diarrhea
3) others=pertussis-like syndrome, acute hemorrhagic systitis (dysuria/hematuria in young boys), musculoskeletal disorders, genital/skin infxns |
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Term
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Definition
1) obtain isolate from symptomatic area
2) direct analysis- rapid
-immunoassays (fluorescent Ig/ELISA)
-PCR/DNA probes
-serological (epidem. purposes only)
3) grow in cell media (can't use for enteric adenoviruses) 2-20 days, observe lytic infxn w/ inclusion bodies |
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Term
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Definition
| -supportive, self-limiting, no treatments |
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Term
| Adenoviruses prevention/control |
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Definition
1) handwashing/cover when sneeze+cough
2) chlorination of swim pools
3) avoid infected pts
4) enteric-coated po vaccine for mil. use (d/c'd in '96, new production expected soon) |
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Term
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Definition
-1/2 proteins for viral rep (i.e. DNA-dependent DNA polymerase and thymidine kinase.
-other half of proteins for host cell interaction (i.e. glycoproteins that promote attachment and immune system evasion) |
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Term
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Definition
1) pentration of host cell 2) capsid, viral-encoded protein kinase, and cytotoxic proteins released into cytoplasm 3) if LAT genes transcribed --> latent infxn; if immediate-early genes transcribed, viral rep. begins
4) capsid produced and "filled" with DNA; exit nucleus via ER
5) viral glycoproteins produced w/ host-cell machinery and incorporated into viral envelope in golgi 6) release via exocytosis or lysis
-infxn can spread through intracellular bridges or syncitia |
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Term
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Definition
1) HSV-1 = cold sores, HSV-2 = genital
2) humans only
3) transmit through mucosa or breaks in skin
4) CD8 T-cells/INF-gamma important for latency
5) fomites can transmit
6) 5 stages a) primary mucocutaneous infxn, b) infxn of ganglia, c) establishment of latency, d) reactivation, e) recurrent infection
7) cytoplasmic granulation, ballooning degeneration of cells, production of mononucleated giant cells |
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Term
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Definition
1) lifelong latency in sensory and autonomic ganglia; subject to reactivation
2) initial response is by PMN, followed by "lymphatic response"
3) emotional/physical stress, immune response can cause reactivation
4) reactivation despite presence of Ig, recurrent infections less severe |
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Term
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Definition
| -transmitted in secretions and by close contact |
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