Virus.pdf

# Vinus ## Contain the Genome RNA or DNA (Never both) - Viral Genome - contains linear or circular DNA, Single Stranded DNA, or linear RNA ## Capsid - Protects the virus - outer layer - Inpenetral cell around the nucleic acid core - made of a number or morphological Sub unit called a Capsomear - m...

# Vinus ## Contain the Genome RNA or DNA (Never both) - Viral Genome - contains linear or circular DNA, Single Stranded DNA, or linear RNA ## Capsid - Protects the virus - outer layer - Inpenetral cell around the nucleic acid core - made of a number or morphological Sub unit called a Capsomear - made of protomears - Gives Symmetry ## Envelope - (vinis is called 'naked vines' if no envelope) - Surrounds the nucleocapsid - Bilayer of lipoprotein and Glycoproteins ## Enzymes - Central role in infection process - Some enzymes contain their own nucleic acid pulimonanes which transcribes the viral genome into MRNA in the replication process ## Obligate Intracellular Parasites - Vinises can only multiply in a living host cell # Vims classification ## I cosahedral - Capsid - Polygon - 12 corners - 20 facets (equilateral triangles) - 30 edges - Most stable - Found in human pathogenic viruses suchas: herpes - Types: - Hexagon - Pentagon ## Filamentous - Linear thin thread / rod Shape - Capsid ## Head-tail - Icosahedral head - Capsid - Filamentous body - (mix of both) ## Viral Tropism Types: - Cellular, Tissue, Host ## Influencing factors of tissue tropism: - Presence of cellular receptors permitting viral entry - Availability of transcription factors involved in viral replication - Cellular receptors of the prokins found on the Cell or viral surface # Viral Infections of The oral Cavity ## Varicella - Zoster (Human herpes virus 3) - Chicken Pox (children) - Shingles (Adults) ## Management - Hydration - Good diet - Non-steroidal / antiinflammatory drugs - Paracetamol, ibuprofen (to relieve fever) ### Chickenpox ### Shingles - Reactivation of the virus - Sits in the Dorsal root Ganglia - Tiggered by trauma, drugs (immunosuppressant) - Virus is dormant-when reactivated it travels through the nerve fibres in the skin - presents unilaterally (one sided) ## Management - Not for nyg to manage but can lead to Ramsay hunt (shingles of the facial nerve) - unilaterally facial palsy - Tinnitus - Change / loss of taste - Causes dry mouth - can present in the mouth - Pt may complain of tooth ache - but isnt as it is just hyposensitivity # Herpangina - Presents on the soft palate. - Present in children aged 3-10 years old - Can be present for up to 10 days - Can still be contagious for 3-8 weeks after getting the virus - can cause difficulty Swallowing # Epstein-Barr Virus - Human herpes vinis 4 - Can cause: - Burkitt's lymphoma - malignant tumour (developing / 3rd wond Countres due to malaria). - Nasopharyngeal Carcinoma common in South China, associated with diet # Oral Hairy Leukoplasia - Most common in people with HIV/AIDS # Paramyxoviridae Vims ## Mumps - Painful Swelling of the parotid gland (side of the face) - Spread through coughs/Sneezes - most contagious 2-3 days before symptoms - Lasts 1-2 weeks - Soft diet - Long term consequences # Measles - measles morbillivirus - Spots can present in oral Cavity - Buccal mucosa - Hard and soft patate # Herpes Simplex Virus 1 and 2 - Primary gingivostomatitis - Palient may present with malaise - Swollen lymphnodes - Eruptive soves around the face inside the oral cavity - lasts 5-10 days - No Scaming - Primary infection ## Genital Herpes - Contract during intercourse/ sexual practices ## Hepetic Whitlow - Recurrent - (Seeing a patient with a coldsore) ## Enchephalitis - Swelling of the brain - Lead to death # Secondary Infection ## Herpes Labialis (cold sore) - Lives in trigeminal ganglion until reactivated ## Stimulation of activation - Stress - Trauma (lip biting) - Sunlight (uv rays) - menstruation - Immunosuppresion - Fatigue