Flashcards in Week 3 - Viral, Fungal, and Parasite Pathogenesis - Ziegler Deck (14)
REVIEW: Basics about influenza virus?
Single stranded RNA virus with a segmented genome.
Clinical symptoms are the results of directly or indirectly from virus replication at:
The target organ!
Most viruses enter human hosts where?
mucose of respiratory or GI tract
How can viruses spread?
-Free in plasma
-nerve fibers (shields them) Rabies
-Direct spread (Flu, in srespitatory system) (respiratory to Gi, adenovirus)
Which has a longer incubation time, localized viruses or disseminated viruses?
Disseminated have a longer incubation time. Sometimes it takes longer to arrive at target organ (mumps and measles)
Localized have a shorter incubation time, often clinical signs occur due to replication at site of infection (FLU)
What are interferons?
Polypeptide cytokines produced by host cells in response to viral infection
usually FIRST line of defense
Can be produced by cells being infected, warns cells around them to batten down the hatches!
What is a mechanism of humoral immunity the cell can use against viruses?
Antiviral antibodies - like Anti-VAP's to neutralze its binding ability
Opsonins can enhance phagocytosis
ALso cytolysis of cells infected with viruses
What are antibodies good for vs. what are cell immune responses good for? In reference to viral infections
Cytolytic infections with viremia and epithelial surface infections
Cell- immune responses good for non-cytolytic infections where cell membranes are antigenically altered to stop antibodies from working
5 types of fungal infections
1- Superficial - keratinized outer layers (they actually eat keratin, YUM!)
2- Cutaneous - epidermis
3 - Subcutanoeous - dermis, subcutaneous tissue, muscles, and fascia
4 - Systemic - begin in lungs and spread
5 - opportunistic - immune compromized people
Explain 3 types of fungi, and explain what dimorphic is:
(this is an objective!)
Molds - they are filamentous, have hyphae
Yeasts - round and unicellular
Dimorphic - exist as yest or fold depending on conditions of the environment (in body grow as yeasts!)
How do antifungals work?
(This is an objective!)
Inhibit ERGOSTEROL synthesis or bind to it to disrupt fungal membrane
Can also inhibit fungal glycan synthesis
What is cytopathogenesis? What are inclusion bodies? How can physicians use them for our benefit?
Cytopathogensis is basically cell injuries.
This may include inhibiting protein synthesis, degrading DNA, disrupting the membrane.
Inclusion bodies are basically remnants of cell damage that you can see and are indicative of specific diseases
What disease would you diagnose in cells containing Negri bodies?
What about Cowdry's type A?
Herpes Simplex Virus