microbiology and immunology Flashcards
gram positive stain
blue
gram negative stain
red
not all organisms are susceptible to gram staining and therefore require specific considerations
true
What is used when finding MTB mycobacterium
acid fast techniques
both syphilis and lyme disease are caused by /also associated with nup and nug
spirochetes
NUG/NUG
treponema denticola
what is required to identify spirochetes
dark field microscopy
lacking distinct shape
pleomorphic
bacteria can be classified based on
oxygen metabolism
what is highly reactive
molecular oxygen
must have oxygen source to survive
obligate aerobes
can grow in the absence of oxygen by using fermentation
facultative anerobes
most disease causing organism is
facultative anerobes
aerotolerant anaerobes
microaerophilic bacteria
cannot tolerate oxgen
can live in periodontal pockets and sulcus
obligate anerobes
microbes exhibit — distinct phases of growth
4
growth is slow at first as bacteria acclimate to their environment
lag phase
Cellular metabolic activity was NOT increased during the
lag phase
growth occurs exponentially
logarithimic (exponential) phase
what is the phase that microogranisms are most prone to breakdown by antimicrobial agents
log phase
no net increase or decrease in cell numbers as nutrients are used up and waste products build up
stationary phase
spherical gram positive cocci usually arranged in chains or pairs
microaerophilic
non mobile
all are catalase negative
streptoccous
streptococcus is divided into three groups
B A G
beta hemolytic
alpha hemolytic
gamma hemolytic
completely lyse red blood cells
beta hemolytic
facultative gram positive cocci
grows in chains
causes numerous infections in humans including pharyngitis strep throat tonsillitis scarlet fever and cellulitis
GAS
group a streptococcus or streptococcus pyogenes
highly communicable and primarly spread through person to person contact
gas
most of the viridian groups are
alpha hemolytic
normal inhabitants of the nasopharynx and gingival crevices
viridans group of streptococcus
some of the viridans group (especially strep mutans) which can bind to teeth by producing dextran polysaccharides in the presensce of sucrose can produce
acid and dental caries
strep mutans metabolize —— which creates an acidic environment which can demineralize enamel
lactic acid
sucrose is also used by strep mutans to produce
dextrans
all other sugars create lactic acid
what is not associated with periodontal disease
strep mutans
dental manipulations can release —– into the blood stream where they implant on the endocardial surface of the heart by producing extracellular glycan
streptococcus viridans
infections with -streptococcus viridans (especially streptococcus mitis) are causative for the majority of
endocarditis cases
principle commensal bacterium of the oral cavity
one of the first microbes to colonize an infants mouth
associated with the tongue
strep salivarius
has powerful arsenal of enzymatic and endotoxic weapons, spherical gram positive cocci arranged in grape like clusters, typical lesions are abcess
staphyloccous
significant endotoxins are coagulase and hylaurandize and major producer of proteins called leuocidins
staphylococcus aureus
what is the most resistant disease causing organism
MRSA
methicillin resistant staphylococcus aureus
what are often the first antibiotic to be used in the treatment of MRSA
vancomycin and bactrim
advanced carious lesion
lactobacillius
gram positive rod
one of the most commonly used probitotics
lactobacillus acidophilus
lump jaw
actinomyces israelii
gram negative rod obligate anerobe pregnancy related gingivitis isolated from pericoronitis implicated in nup/nug
prevotella intermedia
major player in perio disease and gram negative obligate anerobe
porpyromanas gingivallis
idea treatment option in perio disease because of anti collagense properties
tetra
posses surface fimbrae which allow the bacteria to adhere to epithelial and tooth surfaces, also produces collagenese
porp. gingivalis
of the 11 species that colonize humans only two are pathogens. Neisseria menigtidis and neisseria gonorrhoae
true
is stimulated by the presence of female sex hormones inplicated in pregnancy gingivitis
camphylobacter rectus
many studies have proven with conviction that the presence of both streptococcus mutans and lactobacillius are predictive of the development of root surface lesions
true
research had associated —– with root caries in the past but findings suggest that it plays a limited role at bet
actinomyces viscous
most fungi are
obligate aerobes
NEED OXYGEN
typically fungi kill other cells and absorb
nutrients
Normal flora of skin and mucous membranes suppress
fungi
fungi are
eukaryotic
bacteria are
prokaryotic
will kill most bacteria but is ineffective against fungal organisms
antibiotic therapy
when a person is taking antibioitics fungal organisms are unaffected and often overtake the hosts ability to suppress fungal infections
true
most common fungus encountered in the dental setting
candida albicans
superficial candidasis appears as
thrush
systemic infection of candida may involve lungs kidneys heart and
espophagous
treatment of candida albicans
topical nystatin and clotrimazole
systemic tx ketoconazole and fluconazole
helical or icosahedral
a symmetrical structure with 20 faces in shape
to move the info contained in dna to the host cells cytoplasm where protein synthesis and viral replication takes place
role of mRNA
primary function of mRNA
Translation
Transcription is from
DNA to RNA
Once a host cell has been infected by a virus, there are four possible outcomes
1 death
2 transformation
3. latent infection
4 chronic slow infections
classes of viruses are based on
RNA or DNA never both
HIV is an example of
RNA
Hep a c d e influenza virus mumps measles
RNA
epstein bar virus, HPV, Herpes simplex 1 and 2, varcella zoster is an example of
dna
dna has
positve and negative strands
rna has
either positive or negative not both
primary function of mRNA was
translation
transcription is from
dna to rna
true/false
once a host cell has been infected by a virus, there are four possible outcomes
death, transformation, latent infection, chronic slow infections
true
true/false
RNA viruses must provide RNA dependent polymerases (replicase and transcriptase) because host cell cannot replicated RNA
true
examples of RNA viruses include
hep a, c, d,e influenza virus, mumps, measles and
HIV
what cannot be translated into proteins until it is transcribed into mRNA
DNA virus
examples of dna viruses include
hep b, small pox, human papillioma virus, herpes simples 1 and 2. and
Epstein bar virus
HBeAG
high infectivity and active infection
anti- HBsAg
no active disease, immune
HBsAg
disease (acute or chronic)
hep b vaccine is an example of
artificial acquired active immunity
gamma globulin is an example of
passive immnunity
HPV 16 linked to oropharyngeal —
malignancy
how many types of herpes virus are there
8
varicella zoster virus
Epstein barr virus
kaposis sarcoma herpesvirus
herpes virus
varcellla zoster virus causes
chicken pox
the Epstein bar virus is the causative organism for —– —– and may also be implicated in malignancies such as nasopharyngeal carcinoma and burkitts lymphoma
infectious mononucleosis
epv implicated in
oral hairy leukoplakia
herpes virus is the causative organism for
Epstein barr infections
associated with aids
Kaposi sarcoma herpesvirus
causative organism for herpangina
coxsackie virus
what is the immune system made up of
leukocytes
where are leukocytes produced
in the bone marrow
the first line of defense that the immune system relies on is
physical barriers
example skin
what is the second line of defense involving the immune responce
innate or “natural”
acute inflamtion is a —- response characterized by edema, redness, and pain
vascular
neutrophils are
phagocytes
process of —– allows PMNS to sqeeze through endothelials cells to relocate into connective tissue
diapedesis
when something is wrong with neutrophil functions what results
periodontal disease
what are responsible for transporting and processing antigens
macrophages
—- — cells are a group of white blood cells that destroy tumor cells and virally infected cells
natural killers cells
Natural killer cells are not phagocytes
true
—- cells are common at sites in the body that are exposed to the external environment and are found in close proximity to blood vessels
mast cells
what two antibodies are capable of activating the complement system
IgG
IgM
when a cell becomes infected with a virus the host cell secretes a group of proteins called
interferons
defense against infections, mycobacterium tuberculosis, viral, and fungal. Delayed hypsersensitivity
t cells
cellular immunity
allergic response example hay fever
humoral immunity
b cells and plasma cells
the precursors of t lymphocytes arise in the — —- and eventually migrate to the thymus to mature
bone marrow
during the maturation phase, t cells develop specific receptors that allow them to differentiate into two main types of t lymphocytes
t helper cells and t cytotoxic cells
cd4=
helper t
these cells kill virus infected cells without the help of other cells, also capable of killing tumor infected cells
cytotoxic t cells
main players in humoral immunity
B cell
most abundant antibody only one to be able to cross the placental barrier
IgG
which antibody is the most efficeient in agglutination
IGM
most active antibody in response to allergens, binds to mast cells and basophils
IgE
main immunoglobulin in secretions SALIVA
IgA
allergic reaction that appears very quickly after exposure to a previously encountered allergen
type 1 anaphylactic
are the most likely antibiotic class to produce anaphylaction reaction
penicillin
type — blood results in the formation of anti AB antibodies
0
Hypersensitivity reaction types
type 1- anaphylactic reaction
type 2- cytotoxic reaction
type 3- immune complex reaction
type 4- cell mediated or delayed reaction
common example are the Mantoux skin test
type 4 cell mediated reaction
scleroderma is an example of
an autoimmune disorder
scleroderma is associated with
raynauds phenomenon and generalized widening of the periodontal ligament space
what type of hepatitis is a dental hygienist least likely to get
hep e
in plaque biofilm what makes up the bulk of deposits
a. bacteria
b. cytokines
c. acquired pellicle
d. exopolysaccharides
expo
which is the first antibody to be produced after birth? a. IgG b. IgA c, IgM d. IgE
IgM
which blood type can be given to all individuals
0 negative
which of the following organisms is causative for strep throat pharyngitis and scarlett fever
step. pyogenes
which microorganism can be encapsulated with a polysaccharide layer?
a. actinomyces israellil
b. Neisseria menigtidis
c. staphylococcus aureus
d. streptococcus pneumoniae
d.
the complement system aids in the immune response by
a. creating antibodies
b. increasing vasodialation
c. decreasing inflammation
d. increasing lysis and opsonization
d.
in characterizing gram + organisms which of the following characterizes the cell wall structures of these bacteria?
thick 2 layer cell wall structure that stains blue on examination
which microscopic technique must be employed to identify mycobacterium tuberculosis
acid fast staining
at what stage of bacterial growth are organisms MOST susceptible to antimicrobial growth?
a. lag phase
b. death phase
c. stationary phase
d. logarithimic phase
d
which bacteria is an early colonizer that is associated with the tongue?
a. step mitis
b. strep sobrinus
c. strep salivarius
d. step sanguinis
c
which characteristics are associated with porphyromonas gingivalis?
a. gram - bacillius, aciduirc stains blue
b. gram + aerobe produces collagenase
c. gram- rod obligate anerobe surface fimbrae
d. gram-cocci aerotolerant anerobe stains red
c
all of the following are RNA viruses except one. which is the exception
a. hiv
b. mumps
c. hep a
d. Epstein barr
d
which of the following viruses has been linked to a heightened risk of oropharyngeal cancer?
a. coxsackie virus
b. cytomegalovirus
c. varicella zoster virus
d. hpv
d
a positive Mantoux skin test is an ex. of
a. allergic dermatitis
b. tuberculosis diagnoses
c. antibody mediated reaction
d. cell mediated hypersensitivity reaction
d
all of the following are characterisitcs of autoimmune disorders except one.
a. early onset
b. multifactorial
c. antibody mediated
d. more common in females
a
which immune cell is most active in cellular immunity
a. t cell
b. b cell
c. plasma cell
d. macrophage
a
allergies to pollen is an example of
a. iga stimulation
b. mast cell inactivity
c. humoral immunity
d. primarily dependent on t cells
c
a virion is
a. viral envelope
b. complete virus
c. cytoplasmic enclosure
d. remnant of a virus used in diagnostic tests
a complete virus
the shape of most viruses is a. rod like b spherical c. icosahedral pleomorphic
c
