Chapter 15 (EXAM 3) Flashcards
What is the most common portal of entry
The mucus membrane of the respiratory tract, GI next
Parental root
Bacteria introduced by being pushed underneath the skin by needles, bite, surgery or cuts
What are the 3 common pathogenicity factors
Attaching: Most common way to get established.attaches to have an environment to eat and reproduce
Circumvention of the host: Goes around the host and hides so it isn’t recognized
Disrupting homeostasis: Can be mild to severe. Can deprive host of nutrients
What are the 4 virulence factors
N: # of microorganisms
E: enzymes/protiens
E: External structures
T: Toxins
What are virulence factors
The things that contribute to how capable the microorganism is to causing disease
What are the types of enzymes
Callogenases, Kinases, Proteases, Invasins
Callogenases
Group of enzymes that break down collagen. Can invade skin
Kinases
Dissolve blood clots
Proteases
Enzymes that break down proteins
Invasins
Proteins in charge of invading cells.
Allow microorganisms to attach to the outside and rearrange acting proteins that make up outter portions of cell.
Once they do this they can navigate their ways through the cells
What are the external structures
M protien, Mycobacteria, Capsule, Ligands, Opa-protein
M protein
Can be found on surface of certain bacteria, allows for attachment and resistance of phagocytosis ( hard to get rid of )
Mycobacteria
Not gram - or +.
Have waxy cw, resist being eaten and can grow from within phagocytes agar eat them
Capsule
Have adhesions. Are glycoproteins/lipoproteins
Attach to host cell sugars. Found on external structures of bacteria ( cw, fibriae )
Ligands
Bacteria attaching and causing a cell to take it in. Indures endocytosis. Biofilm is an example
Opa-Protein
Found in ghonnerea, used to attach
ID50
Infectious dose for 50% of test populations
LD50
Lethal dose that kill 50% of test populations
Endotoxins
Unintentionally released
Lipids that are part of the gram - cell wall. Found in extra outter lipid membrane of gram - bacteria
Can be released when gram - bacteria is dying to being released/multiplying from phagocyte
Causes fever, vomitting, diarrhea, can lead to shock
When they multiply macrophages can eat the bacteria causing the release of them & release of chemicals
Can survive autoclaving
What happens when a macrophage eats a bacterium
Causes endotoxins to be released, and causes the release of chemicals: Interlukin 1
What does interlukin 1 do
Stimulates more activity int he body to fight infections.
Causes hypothalamus to reset the body temperature which results in fever, hiding iron from bacteria and increases t-cell production and release of transferrin and interferons
Exotoxins
More lethal than endotoxins
Proteins released from gram + organisms very few gram -
Are intentionally released from cells
Have specific modes of action!!!= neurotoxins(nerves), cartiotoxins (heart), neurotoxins (WBC)
Diffuse through bloodstream and are soluble in water base fluid
Can be used over and over again
Can be destroyed by heat or chemicals
What are the 3 types of exotoxins
AB exotoxin
Membrane disrupting
Superantigenic
AB exotoxin
interfere with host cell protein synthesis. A portion interferes while B portion attaches to host cell
Membrane disrupting
lysis disrupting
Superantigenic
activate t-cells to release multiple cytokines. Results are similar to gram- endotoxin intoxication and can lead to septic shock. Induces fever from cytokines
Antitoxins
Immunoglobulin or antibody injections. Preperations of antibodies
AB diseases
botulism, tetanus, cholera, anthrax, scalded skin syndrome, travelers dire, stomach cancer
Superantigen diseases
food poising, toxic shock syndrome
Membrane disrupting diseases
antibiotic associated diarrea, skin and soft tissue infection, gas and food poisoning
Endotoxin diseases
typhoid fever, UTI, meningococcus meningitis
Portals of entry
Respiratory tract Gastrointestinal tract Genitourinary tract Conjunctiva Parenteral route ( skin )
Portals of exit
Mucous membrane
Skin
Parenteral route
