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16 Cards in this Set
- Front
- Back
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Papillomaviruses
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- induce warts on skin/condylomas in mucous membranes
- possess cell tropism for skin/mucosal squamous epithelial cells - more than 100 HPV "genotypes" - cervical cancer/epithelial tumors - naked icosahedral particle - circular dsDNA genome - 10 genes; 8 early, 2 late - two capsid proteins. |
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HPV types that cause most significant human disease
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- 16, 18 cause genital malignancies
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HPV replication
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- infects proliferating epithelial cells
- early proteins produced, viral DNA replicated 50-100 x as an episome - division of cell also duplicates viral DNA - viral DNA replicates to thousands of copies/cell in superficial layers - late genes expressed/virions produced. |
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HPV malignancy
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- episomal DNA can randomly integrate into cellular DNA
- virion production stops, instead HPV E6 and E7 proteins produces - able to immortalize fibroblasts, foreskin keratinocytes and cervical epithelial cells - E6 targets p53 for proteolytic degradation - E7 binds RB, liberating E2F transcription factor, inducing S-phage |
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Polyomaviridae
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- JC Virus, BK Virus
- Icosahedral, dsDNA, circular - ubiquitous, most children infected, asymptomatic - can form persistent kidney infections (uroepithelial cells) - reactivates in immunosuppressed |
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Pathology of JCV
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- can cause progessive multifocal leukoencephalopathy (PML) in brain
- rare, fatal demyelinating disease - immunocompromised |
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Pathology of BKV
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- can cause hemorrhagic cystitis (kidney, bladder, ureter)
- immunocompromised |
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Adenovirus genome
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- linear dsDNA
- 34 genes (20 early) |
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Adenovirus features
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- 50 serotypes of human adenoviruses
- cause different infections - lifelong immunity - can form long-term persistent infections in lymphoid tissue - reactivated in immune suppressed patients |
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Adenovirus disease
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- Pediatric respiratory disease: fever, pharyngitis, tonsillitis, cough
- pharyngoconjunctival fever (PCF); from inadequately chlorinated swimming pools, nasal oral aspiration or direct conjunctival inoculation. |
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Epidemic Keratonconjunctivitis (EKC)
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- Adenovirius
- direct inoculation and ocular trauma infects corneal epithelial cells - can cause permanent visual impairment - prolonged virus shedding |
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Acute Respiratory Disease (ARD)
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- upper and lower respiratory disease in military recruits
- fatal or cause chronic lung damage - effective live virus vaccine discontinued - not seen in civilian populations |
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Immunosuppressed Adenovirus infections
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- causes disseminated infection
- 20% of pediatric allogeneic stem cell transplant patients with ablated immune system get it, 1/2 die |
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B19 Parvoviurs
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- ssDNA
- 5 kbp; 2 early, 2 late virion proteins - host cell must be in S-phase for virus replication (virus can't induce S-phase) - hematopoietic progenitor cells (erythroblasts) have receptor - replicates in bone marrow - autonomous parvovirus |
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Adeno-Associated Virus (AAV)
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- common human parvovirus
- requires adenovirus or herpesvirus helpers - does not cause disease |
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Pathology of parvovirus B19
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- Slapped cheek (erythema infectiosum)
- fever/anemia @ 5 days - exanthema arthritis @ 15 days |
