question

Steriliaztion

answer

No living cells, spores, or viruses

question

Disinfectant

answer

Killing, inhibiting, removing organisms that cause disease, from inanimate objects

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Sanitization

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reducing microbials numbers to levels safe for the public
-dishwasher

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Antiseptics

answer

kill or inhibit infection causing organisms from living tissues
-what you put on a wound

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Germicides

answer

kill a certain organism
-fungicide, viricide, bactericide

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Physical Agents

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Heating-doesnt kill spores
Autoclave-kills all cells and spores
Pasteruization-doesnt kill spores
Baking-kills all cells and spores
Filtration-just removes
UV-damages DNA

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Factors affecting anti-microbial efficiency

answer

Population size
Population composition
Temperature
Concentration of anti-microbial agent
Length of exposure
Local environment

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5 Modes of Killing

answer

Bind to ribosomes, stop translation
Stop cell wall synthesis
Disrupt membranes
Stop nucleic acid synthesis
Inhibit metabolic pathways

question

Bacterial Mechanisms of Antibiotic Resistance

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Prevent drug entrance
Efflux pumps-nonspecific
Drug inactivation-making an enzyme that deactivates the drug coming in
Target modification-changes to RNA sequences in the ribosomes, alterations in tetrapeptide, alternative metabolic pathways

question

2 ways bacteria acquire drug resistance genes

answer

Spontaneous mutations
Horizontal gene transfer-sharing genes, conjugation

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Symbiosis

answer

organisms that spend any portion of their life associated with an organism of another species

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Commensal

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1 benefits, the other is neither harmed nor benefits
-bacteria on our skin, gut

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Mutualistic

answer

Both organisms benefit

-Lichens
-Deep sea H2S vents
-Ruminants
-Termites
-Green flat worms

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Parasitism

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Any disease causing pathogen, 1 benefits and 1 is harmed; least common type of symbiosis

-Photosynthetic sea slugs

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Normal flora

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Organisms that routinely reside on the body's surface
*not in lungs!

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How are normal flora protective?
;

answer

compete for attachment with pathogenic bacteria
produce antimicrobial substances that fight off and help destro pathogenic bacteria
stimulate the immune system, keeps immune system slightly activated

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Infection

answer

when a parasite is multiplying in/on a host

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Infectious disease
;

answer

host cannont function normally due to presence of parasite or its products

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Pathogens
;

answer

cause disease

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Pathogenicity

answer

organisms ability to cause disease

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Virulence
;

answer

degree or intensity of pathogenicity, as indicated by morbidity and mortality rates

question

Three factors affecting parasitiism
;

answer

# of organisms inoculated
virulence of organism
hosts degree of resistance;

question

Symptoms
;

answer

subjective (cant see it)
nausea, pain, loss of apetite;

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Signs
;

answer

something you can observe
rash, fever, swelling

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Infectious disease process;

answer

[image]

question

Exotoxins-4 types

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neurotoxins- affect nervous system
enterotoxins- affect GI tract
cytoxins-affect cellular function
superantigens** unique! over stimulate the immune system, become leaky, 20% of T cells activated

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Endotoxins
;

answer

LPS
only gram negative
sluffed off when gram negative dies
weak immune response
no vaccine made for it
multiorgan failure

question

Innate Immunity Barriers
;

answer

Physical Barriers: skin, GI tract, mucous, respiratory tract, genitourinary tract, eye
Chemical Barriers: antimicrobial peptides**
Molecular defenses: complement, type I interferons
Cellular Defenses
Inflammation
Fever

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Antimicrobial peptides
;

answer

Defensins: found in skin and punch holes in bacteria membranes
Histanin: has antifungal activity, targets mitochondrial membrane inside of fungus-very specific
Lactoferrin and Transferrin-bind to iron so microbes cant get it
baceriocin: (bacteria make this one), produced by normal flora, defense against other bacteria

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Complement functions

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Opsonization:components bind to viruses and bacteria to be better taken up by macrophage
Direct lysis of bacteria-forms pore causing it to lyse
Inflammation;

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Cytokines
;

answer

protein communication molecules
IL-2, IL-4, Type I interferons

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Granular cells
;

answer

Toxic molecules
Mast cells-release histamine
Neutrophils-first reactors, phagocytosis
Basophils-release histamine
Eosinophils-first parasities, allergies

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Agranular Cells
;

answer

Not toxic
T cells
B cells
Macrophages-present antigen to T cells, phagocytosis
Dendritic cells-present antigen to T cells, phagocytosis
Natural Killer cells-kill infected cells and tumor cells

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Chemical mediator HISTAMINE

answer

**Cause inflammation
Activation of vascular endothelium
Increase vascular permeabillity
Increase vasodilation (blood slows down)
Sticky adhesion goes up

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4 Major Benefits of Fever
;

answer

Slows the growth rate of microbes
Inactivates some bacterial toxins
Increases immune system activity
Forces a person to fill ill and allows for rest for energy to be restored

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Primary Response

answer

First exposure to a given antigen, slow to develop therefore innate immunity attempts to provide protection

question

Secondary Response
;

answer

Memory Respsonse
response is more robust and faster

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Antigen
;

answer

a substance that the body sees as foreign or non self, and to which it mounts an immune response

question

Epitopes
;

answer

proteins have epitopes, or short amino acid sequences that are recognized by antibodies and T Cells
*for each epitope there is a B cell

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IgM
;

answer

first antibody secreted during first infeciton, pentameric

question

IgD
;

answer

stays membrane-bound to B cell, function unknown

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IgG

answer

most abundant antibody in the blood, during second infection, crosses placenta and present in serum, small

question

IgA
;

answer

located mostly at mucosal surfaces, very important in binding up pathogens before they can get deeper into the body, dimeric

question

IgE

answer

cause of allergies, constant region binds to cell surfact of mast cells and basophiles activating them to secrete histamine when the antibody binds to pollen

question

Whole organism vaccines
;

answer

Live attenuated-live passaged in culture until no longer pathogenic but still immunogenic
Inactivated or killed-killed with heat or chemicals, but still immunogenic

question

Subunit vaccines
;

answer

Toxoids-exotoxin inactivated, "fake toxin"
Polysaccharide capsules- S. pneumoniae
Viral glycoproteins
Recombinant or native proteins

question

DNA vaccines
;

answer

inject with plasmids that express antigens in host tissues
;
**need to add adjuvants because plasmids get lost in our big human body so adjuvants trigger danger signals better at ativated T cells, adjuvants can also be toxic

question

Recombinant vector vaccines
;

answer

*use of viruses or bacteria to deliver genes of interest;
Dr. Taylor tried this with TB

question

Ability to grow in or on host
;

answer

must have correct pH
must have correct temp
correct O2 content
hemolysins-lyse, RBC, anemia

question

Coagulase
;

answer

forms clot around microbes
;
avoid host immune system

question

IgA protese

answer

cleaves IgA-which is at mucosal surfaces

question

Leukocidins

answer

kill lysosomes in WBC

question

Protein A
;

answer

binds to IgG stops complement binding

question

Hiding within a host cell
;

answer

avoiding host immune system
survive with phagocyte;
-some bacteria are able to escape the phagosome before phagolysomal fusion
-some able to prevent phagosome and lysosome fusion: TB do this

question

Collagenase
;

answer

breaks down collagen

question

H2O2 and NH3

answer

damage tissues

question

Elastase

answer

breaks down basement membranes

question

Hyaluronidase

answer

breaks down connections between cells

question

Lecithinase

answer

breaks down plasma membrane

question

Leishmaniasis
;

answer

an invasive protozoal skin infection

question

Intoxications
;

answer

damage due to toxins produced b microbe outside of the host's body entering the host

question

Damage to Plasma membranes

answer

Clostridium perfringens releases alpha toxin which removes the polar heads from the phospholipid bilayer destroying its integrity, breaks down muscle tissue, gas gangrene

question

Mucocilliary escalator

answer

ciliated cells and mucous trap andpropel microbes away from lungs and into the throat

question

Extravasation

answer

neutrophils squeeze between cellular junctions
-diapedesis
-inflammation

question

Pyrogens

answer

Substances that cause fever
Exogenous pyrogens: LPS, Exotoxins
Endogenous pyrogens: macrophages release IL-1

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