Micro 40 Flashcards

Direct-acting HCV antivirals suppress viral replication primarily by targeting which process?

A. DNA integration
B. Capsid assembly
C. RNA synthesis
D. Protein glycosylation

How are direct-acting HCV drugs typically administered to improve antiviral effectiveness?

A. In combination
B. As lifelong monotherapy
C. Only with antibiotics
D. Only after vaccination

Modern direct-acting HCV regimens are safer than which older treatment combination?

A. Acyclovir plus interferon-beta
B. Sofosbuvir plus ribavirin
C. Ganciclovir plus foscarnet
D. Interferon-alpha plus ribavirin

According to the provided material, direct-acting drugs may be combined with sofosbuvir particularly for which infections?

A. Untreated HCV genotype 1
B. HCV genotypes other than 1
C. Coinfection with HSV only
D. Acute hepatitis B infection

Acyclovir, famciclovir, valacyclovir, ganciclovir, and valganciclovir belong to which antiviral class?

A. Pyrophosphate analogs
B. Guanosine analogs
C. Protease inhibitors
D. Interferon analogs

Which name ending helps identify many guanosine analog antiviral drugs?

A. -navir
B. -buvir
C. -mab
D. -ciclovir

Which group is primarily used against HSV and VZV?

A. Acyclovir, famciclovir, valacyclovir
B. Ganciclovir, valganciclovir, foscarnet
C. Saquinavir, ritonavir, indinavir
D. Ribavirin, sofosbuvir, baloxavir

Which guanosine analog group is primarily used against CMV?

A. Acyclovir and famciclovir
B. Valacyclovir and acyclovir
C. Ganciclovir and valganciclovir
D. Ribavirin and valganciclovir

Acyclovir, famciclovir, and valacyclovir require activation by which viral enzyme?

A. HIV reverse transcriptase
B. HCV RNA polymerase
C. Influenza cap endonuclease
D. HSV/VZV thymidine kinase

Acyclovir undergoes little initial phosphorylation in which cells?

A. HSV-infected cells
B. Uninfected host cells
C. VZV-infected neurons
D. Thymidine kinase–positive cells

Why do acyclovir-like drugs generally cause relatively few adverse effects?

A. Uninfected cells poorly activate them
B. They never enter host cells
C. They target only viral envelopes
D. They stimulate host DNA repair

Ganciclovir and valganciclovir are initially activated by which enzyme?

A. Host DNA polymerase
B. HSV thymidine kinase
C. CMV viral kinase
D. HIV protease

Compared with acyclovir, ganciclovir has which important disadvantage?

A. Poor activity against CMV
B. Greater host-enzyme toxicity
C. Inability to enter cells
D. Complete resistance to phosphorylation

Rhinovirus is destroyed by low pH and is therefore best described as what?

A. Acid-stable
B. Heat-labile
C. Detergent-resistant
D. Acid-labile

Before penetration and uncoating can occur, what is the first step of viral replication?

A. Attachment to cell surface
B. Viral genome integration
C. Capsid protein synthesis
D. Release from infected cells

Neutralizing antibodies prevent attachment by binding which viral component?

A. Viral polymerase
B. Viral nucleic acid
C. Viral attachment protein
D. Host-cell ribosome

Amantadine and rimantadine interfere with viral replication by altering what?

A. Host-cell DNA
B. Viral base pairing
C. Virion internal pH
D. Viral protease activity

By changing virion pH, amantadine and rimantadine prevent which process?

A. Viral uncoating
B. Viral attachment
C. Viral protein cleavage
D. Viral genome integration

Docosanol acts early in infection by inhibiting which event?

A. Viral RNA capping
B. Viral DNA synthesis
C. Capsid disassembly
D. Membrane fusion

Docosanol primarily interferes with entry by which viral category?

A. Naked DNA viruses
B. Enveloped viruses
C. Nonenveloped RNA viruses
D. Integrated retroviruses

Ribavirin, sofosbuvir, and baloxavir share which broad antiviral effect?

A. Inhibition of RNA synthesis
B. Blockade of viral fusion
C. Inhibition of DNA integration
D. Disruption of viral envelopes

Which enzyme is a major antiviral target in herpesvirus infections?

A. Viral RNA polymerase
B. Host thymidine kinase
C. Viral reverse transcriptase
D. DNA-dependent DNA polymerase

Which enzyme is a major drug target in both HIV and HBV?

A. Viral protease
B. Reverse transcriptase
C. Viral thymidine kinase
D. Cap-snatching endonuclease

Why are viral polymerases and reverse transcriptases valuable antiviral targets?

A. They occur only extracellularly
B. They prevent viral attachment
C. Essential and host-enzyme distinct
D. They directly form envelopes

Most antiviral medications belong to which general structural category?

A. Detergent-like molecules
B. Neutralizing antibodies
C. Pyrophosphate metabolites
D. Nucleoside analogs

Nucleoside analog antivirals primarily inhibit which viral components?

A. Viral polymerases
B. Viral envelopes
C. Attachment proteins
D. Fusion proteins

Incorporation of many nucleoside analogs into viral nucleic acid produces what?

A. Increased viral mutation repair
B. Accelerated genome integration
C. Prevention of chain elongation
D. Enhanced protein translation

Besides terminating elongation, nucleoside analogs may disrupt which molecular process?

A. Viral envelope budding
B. Base recognition and pairing
C. Host-cell receptor expression
D. Capsid protein cleavage

Chain termination and abnormal base pairing ultimately produce which result?

A. Inhibited viral replication
B. Enhanced viral attachment
C. Increased cell-to-cell spread
D. Accelerated viral assembly

Pyrophosphate analogs inhibit polymerases by resembling what?

A. A viral nucleotide base
B. A host-cell receptor
C. A viral capsid protein
D. A polymerase reaction by-product

Which pair represents classic pyrophosphate analog antivirals?

A. Acyclovir and valacyclovir
B. Foscarnet and phosphonoacetic acid
C. Ribavirin and sofosbuvir
D. Amantadine and rimantadine

Foscarnet and phosphonoacetic acid classically inhibit which enzymes?

A. HIV reverse transcriptases
B. Influenza RNA polymerases
C. Herpesvirus polymerases
D. Host-cell DNA polymerases

Interferon-alpha and interferon-beta belong to which interferon category?

A. Type I interferons
B. Type II interferons
C. Type III interferons
D. Gamma interferons

Type I interferons establish an antiviral state primarily by promoting what?

A. Viral membrane fusion
B. Viral capsid assembly
C. Host DNA integration
D. Inhibition of protein synthesis

Saquinavir, ritonavir, and indinavir belong to which drug class?

A. HCV polymerase inhibitors
B. Viral fusion inhibitors
C. HIV protease inhibitors
D. Herpesvirus kinase inhibitors

Acyclovir, also called acycloguanosine, has selective activity against which viruses?

A. HIV and HBV
B. HSV and VZV
C. HCV and influenza
D. CMV and EBV

Why is acyclovir particularly selective for HSV and VZV?

A. They encode viral protease
B. They possess RNA polymerase
C. They lack host receptors
D. They encode thymidine kinase

Azidothymidine, also called AZT, was first used against which virus?

A. HIV
B. HSV
C. HCV
D. CMV

AZT suppresses HIV replication by inhibiting which enzyme?

A. Viral protease
B. Reverse transcriptase
C. DNA-dependent RNA polymerase
D. Viral thymidine kinase

Ribavirin impairs nucleotide availability by depleting which molecule?

A. Adenosine
B. Cytidine
C. Guanosine
D. Thymidine

Ribavirin depletes guanosine by inhibiting which enzyme?

A. IMP dehydrogenase
B. Viral thymidine kinase
C. HIV reverse transcriptase
D. HCV protease

Guanosine depletion by ribavirin ultimately causes which effect?

A. Increased viral RNA synthesis
B. Accelerated viral uncoating
C. Enhanced viral attachment
D. Reduced viral replication

A patient receives an antiviral activated mainly inside HSV-infected cells. Which drug group fits this description?

A. Ganciclovir and valganciclovir
B. Saquinavir, ritonavir, indinavir
C. Acyclovir, famciclovir, valacyclovir
D. Ribavirin, sofosbuvir, baloxavir

A patient with CMV receives a guanosine analog that affects host enzymes more than acyclovir. Which drug is most likely?

A. Famciclovir
B. Ganciclovir
C. Valacyclovir
D. Acyclovir

Which drug–infection pairing is correct?

A. Acyclovir—HCV
B. Sofosbuvir—VZV
C. Ritonavir—CMV
D. Valganciclovir—CMV

Which drug blocks herpesvirus polymerase by acting as a pyrophosphate analog?

A. Foscarnet
B. Docosanol
C. Amantadine
D. Saquinavir

Which pair both acts against viral polymerase function?

A. Docosanol and amantadine
B. Acyclovir and foscarnet
C. Ritonavir and interferon-alpha
D. Baloxavir and docosanol

Which therapy inhibits protein synthesis rather than directly inhibiting a viral polymerase?

A. Acyclovir
B. Foscarnet
C. Type I interferons
D. Azidothymidine

Which comparison correctly distinguishes docosanol from amantadine?

A. Fusion blockade versus uncoating blockade
B. Protease blockade versus polymerase blockade
C. DNA inhibition versus RNA inhibition
D. Attachment blockade versus chain termination

Which statement correctly distinguishes ribavirin from AZT?

A. Ribavirin blocks fusion; AZT blocks attachment
B. Ribavirin blocks protease; AZT blocks polymerase
C. Ribavirin treats VZV; AZT treats CMV
D. Ribavirin depletes guanosine; AZT blocks RT