C-12 Flashcards
(36 cards)
anatomy, physiology, and normal flora of the oral cavity
crown, enamel, periodontium tissue around tooth
flora: bacteria, yeast
How is saliva produced and how does it help protect teeth and prevent infection?
by salivary glands; contains lysozyme, calcium, IgA and antimicrobial peptides, and neutral pH - Calcium helps re-mineralize enamel
What are the structures of teeth and periodontium?
gingiva
alveolar bone
cementum
PDL
formation of plaque and calculus, roles of Streptococcus mutans and acid-producing bacteria
s. mutans grows on teeth and anchors biofilms to teeth
formation of dental caries, roles of Streptococcus mutans and acid-producing bacteria
s. mutans and yeast interact and enhance infections that lead to dental caries - yeast overgrows
What type of metabolism produces acid in the mouth and what environmental conditions are required for this metabolism
lactic acid - anaerobic fermentation
Porphyromonas gingivalis - gingivitis
virulence: Adhesins, anaerobe
transmission: normal flora
signs: swollen gums
tx: proper hygiene and avoid sugars
morphology: gram - rods
affected tissues: gums (gingiva)
Porphyromonas gingivalis - periodontitis
virulence: same
transmission: same
signs: bone loss, receding gums
tx: same
morphology: same
affected tissues: gums and bone
Porphyromonas gingivalis – how does it cause inflammation?
pro-infammatory organism - bacteria buildup under tooth and detachment of gingiva
Which is reversible – gingivitis or periodontitis?
gingivitis
Oral thrush (Candida albicans)
yeast
Mumps (Mumps virus)
virulence: adhesions
transmission: direct contact, fomite contaminated with saliva
signs: swollen salivary glands
tx: MMR vaccine
morphology: enveloped, ssRNA
affected tissues: parotid salivary gland
anatomy, physiology, and normal flora of the gastrointestinal tract, role of the stomach, small intestine, large intestines, and liver
flora: bacteria, enterics, virome, fungi, archaea
What are the mechanisms of diarrhea?
Diarrhea is the increase in
volume of stool or frequency of defecation
What is meant by secretion versus absorption in the intestines? What sorts of things are absorbed and secreted by the small intestine and large intestine?
into cells = absorption
into lumen = secretion
absorbs nutrients, water, salts
What must microbes be able to do to survive stomach acid and make it to the intestines?
hydrolyze macromolecules (?)
Staphylococcal enterotoxicosis – Staphylococcus aureus
disease: Bacterial intoxication - Staphylococcal food poisoning
virulence: enterotoxin
transmission: Contaminated food – bacteria survive salt, toxin is heat stable and can withstand cooking
signs: Intense cramping, vomiting, and diarrhea ~24 hours
tx: Self-limiting, proper food handling, fluid replacement
morphology: Bacteria – gram positive staphylococci
affected tissues: intestines
Aflatoxin poisoning – Aspergillus
disease: Fungal intoxication - Aflatoxin poisoning, liver cancer, liver cirrhosis
virulence: Aflatoxin
transmission: Contaminated food – improperly stored grains and legumes
signs: Nausea, vomiting, pain, severe damage to liver (jaundice)
tx: Regulate foods – no specific antidote for poisoning
morphology: Fungus – mold
affected tissues: liver
enterotoxigenic E. coli
disease: Travelers’ diarrhea/ dysentery
virulence: Shiga toxin, T3SS, enterotoxins
transmission: Fecal-oral: contaminated produce/meat
signs: Dysentery – bloody diarrhea
tx: Rehydration/fluids – no
antibiotics if EHEC
morphology: Gm (–) rods, flagella
affected tissues: intestines
Salmonella typhimurium
disease: Salmonellosis, Typhoid fever
virulence: T3SS (Type 3 secretion system) Enterotoxins. S. typhi - capsule
transmission: Fecal-oral: food/carriers
signs:
Shigellosis – can cause dysentery
Typhoid fever: rash and fever
tx: Rehydration/fluids - Fluoroquinolones or macrolides, S. Typhi vaccine
morphology: Gm (–) rods, flagella
affected tissues: intestines
Shigella dysenteriae
disease: Shigellosis / dysentery
virulence: Shiga toxin, T3SS, enterotoxins
transmission: Fecal-oral: food/water
signs: Dysentery – bloody diarrhea
tx: Rehydration/fluids – Fluoroquinolones
morphology: Gm (–) rods, no flagella – actin “comets”
affected tissues: intestines
Vibrio cholerae
disease: cholera
virulence: Cholera Toxin – electrolyte loss
transmission: Fecal-oral route through contaminated water
signs: Rice-water stool
tx: Doxycycline and fluid replacement, Vaccine
morphology: Water-dwelling gram (-) vibrio
affected tissues: intestines
Campylobacter gastroenteritis – Campylobacter jejuni
disease: Most common diarrhea in US
virulence: Endotoxins, cytotoxins
transmission: Fecal-oral, particularly undercooked chicken
signs: Diarrhea, dysentery potentially
tx: Antibiotics, avoid antacids
morphology: Gm (-) helical, flagella
affected tissues: intestines
Clostridioides difficile (C. diff)
disease: C. diff – pseudomembranous colitis –
antimicrobial-associated diarrhea
virulence: Toxin A and Toxin B
transmission: Endogenous flora – overgrowth triggered by antibiotic therapy
signs: Diarrhea, colitis
tx: Fecal Microbial Transplant (FMT), fluid replacement, antibiotics (if they still work)
morphology: Anaerobic gram (+) endospores
affected tissues: intestines
