chpt 15: mechanics of pathogenicity Flashcards
what is the ability to cause disease known as
pathogenicity
virulence is
the extent of pathogenicity
what are the mucous membrane portal of entry
- respiratory tract
- GI tract
- genitourinary tract
- conjunctiva
- skin
- parenteral route
what covers organs
- mucous membranes
which portal of entry is the easiest and more frequent
respiratory tract
examples of illness caused by entry through resp tract
- common cold
- pneumonia
- tb
- influenza
- measles
how is the GI tract affected by disease
food, water and contaminated
- polimyelitis
- Hep A
- typhoid fever
- amebic dysentry
- giardiasis
- shingles
are examples of
GI tract entry diseases
examples of GU entry infections
- STIs
- conjuntivtis
- tracoma
- opthalmia
- neonatorum
entry through
conjuctiva
how are infections caused through the skin
- broken skin
- hair follicles
- sweat glands
how are infections caused by the parenteral route
- bypassed skin, straight into tissue or mucous membrane
examples of parental route infections
- insect bites
- catheter
- surgical wound
- injections
HIV, TETNAI, AND GANGRE
will disease occur if it doesnt enter through preferred spot
maybe not
what is the prefered route of s.typhi
swallow
how many preferred routes does b.anthracis have
3`
function of adhesion/ ligands on pathogens
bind with receptor on host to cause disease
structure of host receptor
sugar aka mannose or fructose
what is made of glycoproteins or lipoproteins on a pathogen
adhesion/ ligands
example of adhesion/ ligands on a pathogen
- capsule
- m- protein
- mycolic acid
what does adherence mean
controlled or prevented infection
which bacteria has a capsule
s. mutants
function of glucoyltransferase formed by capsule on s.mutants
- metabolize sucrose
end product after sucrose metabolism
- glucose and fructose `
what grows layer by layer to form plaque
glucan (further broken down glucose)
what does fructose breakdown to + function of it
acid that degenerates tooth structures and nerves
cell wall components of attachment
- mycolic acid
- m proteins
- frimbriae
which bacteria has m proteins outside the cell wall and frimbriae
s. pyogenes
resistant properties of m proteins
acid and heat resistance
what immunity to s.pyogenes depend on
bodys production of antibody specific to M-proteins
what makes up the cell wall of mycobacteria tb
mycolic acid
how does mycolic acid increase virulence
evades phagocytes
what are extracellular enzymes aka exoenzymes
- secreted enzymes into body
types of exoenzyemes
- coagulase
- kinase
- hyaluronidase
- collagenase
which exoenzyemes forms blood clots that act as protection from phagocytosis
coagulase
example of coagulase
s. auresus in walling of procress in boils
function of kinase
breaks down blood clots to isolate infection
what kinda of exoenzyemes does s.pyogenes use and its function with it
kinsase, functions to break blood clots which causes heart attack
which exoenzyemes functions to hydrolyzes hyaluronic acid
hyaluronidase
function of hyaluronic acid
hold muscle and tissue
what happens with hyrolyzing of hyaluronic acid
- breaks muscle and tissue
- blackening of infected wounds
- invade body/ help microbe spread
what happens with hydrolyzing of hyaluronic acid
- breaks muscle and tissue
- blackening of infected wounds
- invade body/ help microbe spread
examples of disease that use hyaluronidase
c. perfringes = gangrae
c. pyogenes = flesh eating
what exoenzyme may be mixed with a drug to promote spread of it
hyaluronidase
what breaks down/ hydrolyzes collagen causing muscle to fall apart and facilitates spread of gas gangrene
collagenase
what antibody is produced in defence against pathogens of mucosal surface
IgA
IgA protease function
destroys antibodies
what does n.gonorrhea and n.meningisits produce
IgA protease
what causes disease without penetrating the body
- dental caries
- acne
do phagocytes move through biofilm
no
do phagocytes move through biofilm
no
how do bacterial pathogens damage host cells
- sidespores
- direct damage
- toxins
function of sidespores
damage host cells by stealing/ taking iron, which causes bacteria to increase
what occurs once pathogens attach to host cells, use nutrients and accumulate waste products
direct damage
examples of diseases using direct damage
- e. coli
- shigella
- salmonella
- n. gonorrhoea
poisonous substance that are produced by certain microbes is known as
toxins
whats the primary factor of pathogenic properties
toxins
how are toxins transported
blood and lymph
symptoms of toxins
- fever
- cardiovascular disturbances
- diarrhea
- shock
why do symptoms of toxin occur
inhibit protein synthesis
- destroy blood cells and bs
disrupts NS by causing spasms
intotoxications is caused by
presence of toxins
what type of toxin is mostly Gram + with a few gram -
exotoxin
when are exotoxins produced
during metabolism/ growth inside bacteria
what are exotoxins made of
proteins
what type of toxin produces antitoxins
exotoxin
function of antitoxin
provide immunuty
signs and symptoms of exotoxins are
specific, different, simple diagnosis
how do exotoxins excrete their effects
destroys parts of host or inhibit metabolic functions
what are toxoid vaccines
- inactive/ altered exotoxins
- stimulate antitoxin production as immunity
which type of toxin circulates throughout body, is soluble in bodily fluids and easily diffuses
exotoxin
how does botulism occur
ingestion of exotoxin
example of intoxication illness
staphylococcal food poisoning
what is part of bacterial cells and not a metobolic waste
endotxin
what is part of bacterial cells and not a metobolic waste
endotoxin
what type of bacteria release endotoxins
g -
when are endotoxins release
during infection from cell wall (lipid A) or death of bacteria
structure of endotoxin
lipid
how do endotoxins exert their effect
macrophages releasing cytokines in increase conc
- activate blood clotting proteins
which toxin has the same signs and symptoms
endotoxins
signs and symptoms of endotoxins
- fever
- nausea
- diarrhea
- dysentry
- miscarriage
- clotting
- spetic shock
function of antibiotics with endotoxins
improve liver lipase breakdown of endotoxins
what enhances effect of endotoxins
antibodies
A-B toxins examples
- diptheriotoxin
- botulinum
- tenanospasms
- cholera toxin
part A of A-B toxins function
active enzymatic part
examples of exotoxins
- A-B toxins
- suprantigens
-membrane disruptions
what part of the A-B toxins attaches and binds to cells
B
what was the first toxin to be studied
A-B toxin
function A in diptheriotoxin
- shuts down protein synthesis killing cell
when does B bind to nerve cells at NMF and A inhibits ACh resulting in flaccid paralysis and no muscle tone
botulinum
what happens with tetanaospasms
- B binds to neurons at NMJ
-A inhibits GABA which shuts down relaxation
what is back paralysis and possible spine fractures known as
opsitholens
muscle spasms in the mouth cavity is known as
lock jaw
when does A bind to GI tract and results in cells pumping out a out of water with the help of cAMP
cholera toxin
what causes breaks in eukaryotic DNA
genotoxins, hemophilus ducreyi and helicobacter spp
disrupting phospholid layer and making proteins channels in pls mem is known as
membrane disruption
how does membrane disruption contribute to increased virulence
- killing host cells
- aiding in the escape of bacteria
what produces leukocidins and hemolysins
streptococcus and staphlycoccous
what disease produces protien channels
s.aurues
what is caused by erthyrogenic toxin
s. pyogens
does one have a fever with s. pyogens
no
when does hemolysisn in B hemolytic occur
with s. pyogens
what disrupts the phospholid layer
c. perfringes
what L monocytes produce
MAC
which exotoxin is resposible for high infection with intense immune response
superantigents
what does the body release of with supra antigens
- cytokines produced of T cells
what toxin goes all over the hosts body and the effects of it are seen when it reaches all over vital organs
superantigens
symptoms of superantigens
- nausea
- vomiting
- diarrhea
- shock , TSS caused by s. aureus
how fast food poisoning by s. aures take place
1-6 hours, sudden, violent
function of cytokines
- regulate immune response
- mediate cell- cell communication
what cuases a fever with endotoxins
bacterial cell death
treatment for fever
aspirin and Tylenol cuz they inhibit synthesis of prostaglandins
how is fever produced in endotoxin
digestion of microbe releasing LPS
- which causes macrophages to relese IL-1 and TNF = fever
function of IL-1
goes to hypothalamus through blood and secretes prostglandins
function of TNF
- binds to tissues in body and alters their metabolism
- damages blood capillaries and increases permeability = loss of fluid
examples of endotoxin producing bacteria
- s. typhi
- proteus spp (UTI)
- n. meningitis
what causes weakend BBB
endotoxin of hemphilus influenza type b
start of a fever
- chills and shivering
- increased IL-1
-sweating
- decreased IL-1
= getting better is part of
2nd stage of fever/ crisis stage
in what disease does a fever go back and forth between start and crisis stage
malaria
