Biofilm formation and pathogenesis

Question 1

pathogenesis

Answer 1

The progression or course of a disease (the development of infectious disease depends on invasion potential, infection within the body, and the host response)

Question 2

pathogenic

Answer 2

Has a parasitic potential
Can form parasitic relationship with the host, microorganism invades host (invasion potential), the invasion causes disease in host

Question 3

Non-pathogenic

Answer 3

Require conditions human hosts cannot provide (not capable of invading the host or causing disease)

Question 4

Immunocompromised

Answer 4

Immune system has been permanently weakened by pre-existing or coexisting conditions

Question 5

Immunodeficient

Answer 5

Healthy individuals that encounter a new pathogenic strain, which do not have adequate defenses

Question 6

Pathogenicity

Answer 6

Ability of a parasite to gain entry to a host and produce disease (strength of the microorganism - infection potential)

Question 7

Virulence

Answer 7

The degree of pathogenicity (ability of microbe to) cause an infection

Question 8

Virulence factors (steps)

Answer 8

1) Invade host defenses
2) Inactivate host defenses
3) Destroy host tissues or cells
4) Survive in the environment between infections

Question 9

capsule

Answer 9

• Sticky, adhere to hosts tissues (Leads to colonization)
• Resists phagocytosis
• Resists antibiotics

Question 10

endospore/spore

Answer 10

Allows microorganisms to resist severe environmental conditions

Question 11

pili

Answer 11

• Adhesion and colonization
• Antigenic nature is variable
• Transfer of genetic information via sex pilus

Question 12

collagenase

Answer 12

Destroys hosts collagen, allowing them to spread through host tissues

Question 13

penicillanse

Answer 13

Destroys certain penicillin by attaching the beta-lactam ring of penicillin molecule

Question 14

hyluronidase enzyme

Answer 14

• Spreading factor dissolves hyaluronic acid, the cementing substance holding cell together
  Allows rapid spread through host tissues

Question 15

lecithinase enzyme

Answer 15

Destroys host red blood cells, causing anemia

Question 16

coagulase

Answer 16

Converts fibrinogen to fibrin, allowing fibrin to coat bacteria to make them appear as normal host tissue

Question 17

stahylokinase and streptokinase

Answer 17

Converts plasminogen to plasmin, which lyses fibrin in blood clots to remove them and allow infection to spread

Question 18

immunoglobulin, proteases

Answer 18

Destruction of IgA antibodies to decrease host immune response

Question 19

lipases

Answer 19

Hydrolysis of fats to derive energy for the invading microorganism

Question 20

leucocidins

Answer 20

Destroy hosts white blood cells, reducing effectiveness of phagocytosis

Question 21

hemolysin

Answer 21

Destroys host ref blood cells, causing anemia

Question 22

pneumolysin

Answer 22

Causes osmotic damage in host cells, including defensive cells

Question 23

hyrdrogen proxide

Answer 23

Respiratory burst causes oxidative damage to host cells, including defensive cells

Question 24

Exotoxin

Answer 24

gram positive and negative, released from cell, high toxicity, induces production of antibodies, toxoids use as vaccines, low heat stability, tents, botulism, diarrhea

Question 25

Endotoxin

Answer 25

gram negative, produced by LPS, low toxic, causes fever, poorly antigenic, high heat resistant, sepsis, endotoxic shock

Question 26

composition of biofilm

Answer 26

collection of microorganisms adhere to each other on a surface - imbedded in the extracellular polymeric substance (EPS) - slime
- EPS protects, allows communication

Question 27

Life cycle of biofilms

Answer 27

1) Initial attachment (free floating attach to surface, reversible - weak attachment)
2) Irreversible attachment (irreversible adhesion, uses capsules or pili)
3) Maturation I
4) Maturation II
5) Dispersion - (Bacteria colony are able to distach from OG colony and disperse)

Question 28

stages of infectious disease

Answer 28

Stage 1) incubation period - time interval from exposure to onset symptoms
Stage 2) prodromal period - period characterized by appearance of nonspecific symptoms (fever, headache, rash, etc)
Stage 3) acute illness - signs and symptoms that are specific to the infectious disease
Stage 4) recovery period - illness disappears and person returns to health

Question 29

portals of entry

Answer 29

skin and mucous (reduce risk - cell-to-cell attachment, layers, physical barriers, tough, resilient)

Oropharynx and gastrointestinal (GI) tract (reduce risk - chemical barriers, mechanical movements, ‘flush out”

Respiratory tract (reduced risk- tight barrier, physical barrier, mucus entraps, coughing, sneezing)

Genitourinary tract (reduced risk - physical barriers, Acidic PH secretions, flushing action)

Question 30

microbial distribution within the body

Answer 30

1) Local spread - opening to the exterior (microbes can enter open lumens)
2) Lymphatic spread - microbes entering through loose connective tissue though lymphatic capillaries
3) Circulatory spread - general circulation once in body to reach organs
4) Central nervous system, and peripheral nerve spread - spreading through CSF to spinal cold and brain

Question 31

Acute vs chronic microbial infection

Answer 31

Acute - the # of microorganisms quickly increases, cause rapid onset symptoms
Chronic develop over an extended period of time