Lecture 1 Flashcards
What is this lecture about?
Virus structure, classification and replication
What are the 6 infections that have been implicated in cross-infection in dental surgery?
-Herpes Simplex Virus (HS) -Varicella zoster virus (VZV) -Human immunodeiciency virus (HIV) -Hepetitis B virus (HBV) -Hep C (HCV) -Hep Delta (HDV)
What are the implications of HPV in the oral cavity?
HPV infects the oral cavity and turned out to be one of the main causes of oral cancers.
Which one has greater risk given appropriate preccautions? patient or dentist?
Patient.
What are some bacteria that causes dental infections?
Mycobacteria, Pseudomonas and legionella
What are the 5 bullet point characteristics mentioned in th lecture about viruses?
-Minuscule, acellular and infectious agents have both DNA OR RNA -Causes infections to humans animals and plants -Causes the majority of diseases plaguing the industrialized world -Cannot carry out any metabolic pathway -Neither grow nor respond to the enviroment.
What are the extracellular state characteristics for viruses?
-THe extracellular state is called Virion -Protein coat (capsid) surrounds nucleic acid -Nucleic acid and Capsid is called nucleocapsid - SOME have phospholipid envelop -the outer most layer provides protection and recognition sites for host cells.
What is the intracellular state?
-Capsid removed -The virus exists as nucleic acid interacting with viral and host protein
What are virions?
They’re complete virus particles include nucleic acid, capsid and in some cases an envelope.
What is the morphology of capsids? 4 bullet points
-Provide protection for viral nucleic acid -provides Means of attachment to host’s cells -Composed of proteinaceous subunits called “Capsomeres” -Capsomeres can be made out of one protein or multiple.
What are some viral shapes? How are they classified?
-They’re classified by virion shape -Some basic shapes are helical, polyhedral and complex =
What is the VIral envelope and how do viruses acquire it? What is its composition?
-Acquired from host cell during viral replication or release -Envelop is a portion of membrane system of the host -Composed of proteins and phospholipids .-Some proteins virally coded glycoproteins (Spikes) -Envelope proteins and glycoproteins play role in host recognition.
What are the draw backs and the pros of having an envelope?
-Enveloped viruses are more fragile outside host -Enveloped viruses are less likely to be recognized and attacked by host system
How are viruses classified?
-Type of nucleic acid -Presence of envelope -Shape -Size Viral genra is recognized into families
What are the relative sizes of virions?
They’re a fraction of the size of an ecoli bacteria which is a fraction of the size of a red blood cell.