Test 1 Flashcards
About 2/3 of blood leukocytes (white blood cells) are…
PMNs
Life span of a PNM outside the bone marrow?
short-lived cells. In the blood they have a half-life of only 6 hours
At inflammation sites the capillary endothelial cells express ____________________that the PMNs grab onto
cell adhesion molecules (CAMs)
are the major defense features in crevicular fluid. Crevicular fluid comes from the capillaries below
IgG and PMNs
process and present external Ags on class II HLA molecules
The M-cells
Viridans group and species (mostly a-hemolytic = produce a ‘green’ coloring on blood agar), facultative, produce considerable extracellular matrix, sugar-substrate (= saccharolytic), acidogenic, many tolerate low pH well.
Streptococcus
Found in plaque, mucosa, and respiratory tract, may
cause of purulent (= pus-forming) disease.
o constellatus
o intermedius
o anginosus (some b-hemolytic)
St. anginosus-group. Found
Found in plaque, sugar substrate, produces insoluble polysaccharides, grows well at low pH and produces large amounts of lactic acid – a major cause of caries! Requires solid surface (like enamel) biofilm for optimal colonization, therefore few in edentulous young and old.
S. mutans-group.
‘Pioneer’ species on teeth, make insoluble and soluble
polysaccharides, found on plaque and mucosa. Most common isolated bacteria from subacute bacterial endocarditis; but, mainly ‘good guys.’
S. mitis-group.
S. mutans-group to remember
o mutans*
o sobrinus*
S. mitis-group to remember
o sanguinis
o gordonii
o oralis
o mitis
Colonizes much of the mucosal surface, especially
tongue (acquired within hours of birth), major source of bacteria in saliva, generally considered a ‘good guy.’
S. salivarius-group.
Remember salivarius
Formerly classified as ‘enteric’ streptococci, now placed in this new genera. Facultative, opportunist infections; able to survive harsh environments - significant nosocomial problem. commonly implicated in endodontic root canal failures and persistent infections.
Enterococcus
is commonly implicated in endodontic root canal failures and persistent infections.
E. faecalis
(i.e., found only here: in the mouth) - forms a major portion of plaque flora, increases with gingivitis and associated with root caries, produces extracellular matrix, sugar-substrate, tolerates low pH.
Actinomyces. Autochthonous
Can cause systemic invasive actinomycosis)
A. israelii
etc. Increased numbers correlate well with a high- sugar, ‘cariogenic’ diet (tests are available), associated with dentin caries and the ‘advancing front’ of caries lesions, produces extracellular matrix, sugar- substrate, tolerates low pH well, facultative.
Lactobacillus acidophilus,
Common Aerobic Oral Gram-Negative Cocci: diplococcus, saccharolytic, early colonizers, produce extracellular matrix, some species can metabolize lactate (in theory this could reduce caries by removing acid!), found in ‘mature’ plaque.
Neisseria
Common Anaerobic Oral Gram-Negative Cocci: asaccharolytic, can metabolize lactic acid (in theory could decrease caries by removing acid!), common in oral mucosa and plaque, like Neisseria found in ‘mature’ plaque (again, why do you think?).
Veillonella alcalescens
Common Oral Gram-Negative Rod (formerly Actinobacillus). More common at periodontal disease sites and aggressive periodontitis in young adults than at healthy sites, produces a leukotoxin.
Aggregatibacter actinomycetemcomitans (AA)
