Pathogenicity Test 4 – Flashcards
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Unlock answersFor genetic capability were are three places there are genes? |
1. on chromosomes 2. on plasmids 3. on prophage |
With genes on the plasmids what adds virluence genes to plasmids? |
Transposons |
What are transponsans? |
What are some nutrient based factors? |
What are some environmental factors? |
What is infection? |
Growth and multiplication of parasite on or within host |
What is infection dependent upon? |
Complementary contact |
What is a pathogen? |
Causes infectious disease |
What are the two types of pathogen? |
1. Primary (frank) pathogen 2. opportunistic pathogen |
What is pathogenicity? |
The ability to cause disease |
What is virulence? |
Degree of intensity of pathogenicity |
What are the three characteristics of the pathogen that determin virulence? |
1. Infectivity 2. Invasiveness 3. Pathogenic potential |
What is infectivity? |
The ability to establish point of infection |
What is invasiveness? |
The ability to spread |
What is the pathogen potential? |
The degree to which the pathogen can cause damage to the host. |
What are the two types of pathogenic potential? |
1. Toxigenicity 2. Immunopathology |
What is toxigenicity? |
The abiltiy to produce toxins |
What are two toxins produced in toxigenicity?
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1. Clostridium tetani 2. Corneybacteria diptheria |
What is immunopathology? |
The ability to trigger exaggerated immune responses |
What would be an example of immunopathology? |
Influenza |
What are primary (frank) pathogens? |
What is opporunistic pathogens? |
What are the two ways to measure virulence? |
1. Leathal dose 50 (LD50) 2. Infectious dose 50 (ID 50) |
What is Leathal dose (LD50)? |
The number of pathogens (mivrobes) that will kill 50% of an experimental group of hosts. |
What is an Infectious dose 50 (ID50)? |
The number of pathogens that will infect 50 % of an experimental group of hosts |
What are the two ways pathogens transfer in the environment? |
1. Direct contact 2. Indirect contact |
What are 3 examples of direct contact? |
coughing, sneezing, and body contact |
What are five examples of indirect contact? |
1. soil 2. water 3. food 4. vectors 5. fomites |
What are vectors? |
Transmission by living organisms |
What are fomites? |
Transmission by inanimate objects |
What are the three portals of entry? |
1. body surfaces 2. parenteral 3. vectors |
Where is the body surface a portal of entry? |
Cracks in skin, hair follicles, sweat glands, mucous membranes (major portal) |
What are parenteral portals of entry? |
Needle sticks, blood transfusions, and organ transplants |
What is a vector for a portal of entry? |
It is a organism that transmits pathogens from one host to another |
Name three Adherence Factors? |
1. Capsule/Slime Layer 2. Adherence Proteins 3. Fimbriae (Pili) |
What are two examples of the capsule/slime layer? |
1. Pathogenic E. coli attaches to brush border 2. Strep. mutans binds to tooth surface |
What are adherence proteins? |
They bind to specific cell surface protein |
How is Strep. pyogene and example of adherence protein? |
The M protein binds to epithelial cells. |
What are two examples of Fimbriae (pilli) as adherence factors? |
1. They are used in Salmonella: epithelia intestinal cells 2. They are used in Pathogenic E. Coli: Epithelial cells in intestines |
What are the two types of colonization and growth |
Availability of nutrients and Availability of trace elements
|
What gives optimal growth conditions? |
Availability of nutrients |
An example of a growth factor that has rapid growth on the placta is the ______? |
Brucella abortus (uses erythritol) |
Fe is an example of what type of colonization and growth? |
Availabiltity of trace elements |
What are the two "ferrins" that scavage Fe. |
Transferrin and lactoferrin |
What does transferrin use to remove Fe from the transferrin? |
Specific Siderophores |
What are the three types of infection of growth and multiplication of bacterial pathogen?
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1. Localized 2. Systematic 3. Toxemia |
Which infection begins as a local infection in the Kidneys, Lungs, and intestines. Also has septicemia. |
Systematic |
What is septicemia? |
Presence of bacteria or their toxins in the blood |
What type of infection has presence of toxins in the blood? |
Toxemia |
What is the ability of the pathogen to grow in host in vast numbers that inhibits host cell f(x)? |
Invasiveness |
An example of invasiveness would be _________ _________ which has a capsule that allows adherence and prevents phagocytosis. (overgrowth impairs cell f(x)) |
Strep. pneumoniae |
What is the ability to cause disease by means of preformed toxin that inhibits host cell f(x) or kills host cells. |
Toxicity |
What would be an example of Toxicity: ____________ ___________: has slow growth at wound site (toxin is the killer) |
Clostridium tetani |
What are two types of virulence factors? |
1. Enzymes that destroy host cell components or manipulate the immun response 2. Pathogencitiy Islands |
What are the 6 enzymes that destroy host cell components or manipulate the immune response? |
1. Collagenase 2. Coagulase 3. Streptokinase 4. Lipases 5. Proteases 6. Nucleases
|
What are Collagenase: |
destroys intercellular cement (Breakdown collagen that forms the framework of connective tissues; allows the pathogen to spread) |
What are Coagulases? |
Generates fibrin clots (Coagulaes (clots) the fibrinogen in plasma. The clot protects the pathogen from phagocytosis and isolates it from other host defense.) |
What is Streptokinase? |
Breaks down fibrin clots (A protein that binds to plasminogen and activates the production of plasmin, thus digesting fibrin clots, this allows the pathogen to move from the clotted area) |
What are Lipases? |
Breakdown membranes
|
What are proteases? |
Break down antibodies |
What are Nucleases? |
DNase |
What are large segments of DNA that carry a number of virulence genes. |
Pathogenicity Islands |
For the regulation of Bacterial virulence factors what can control the expression of virulence genes? |
Environmental factors |
What is the pathogen whose gene for diptheria toxin is regulated by iron? |
Corynebacterium diptheriae |
What is the pathogen that expression of virulence genes increases at elevated body temperatures (takes advantage of fever)? |
Bordetella pertussis |
What is the pathogen whose gene for cholera toxin is regulated by pH and temperature? |
Vibrio cholerae |
What is the definition of toxin? |
A specific substance that damages a host |
What are dieases that result from entry of a specific preformed toxin into a host. |
Intoxications |
What are two examples of Intoxications? |
1. Staph aureus enterotoxin 2. Aflatoxins from aspergillus in pet food |
What is the condition caused by tozins in the blood of the host? |
Toxemia |
What are the toxins that interfere with protein syntesis? |
AB toxin |
What is an example of Ab toxin? |
Corynebacterium diptheria |
What are the toxins that target nerve tissues? |
Neurotoxins |
What are two examples of Neurotoxins? |
1. Botulinum toxin 2. Tetani toxin |
What is the toxin that blocks the release of acetylcholine? |
Botulinum toxin |
What is the toxin that binds inhibitory interneruons? |
Tetani toxin |
What are the toxins that target the intestinal mucosa? |
Enterotoxins |
What is an example is enterotoxin? |
E. coli O157.H7 |
What are the toxins who target gerneal tissues? |
Cytotoxins |
What are the two examples of the cytotoxins that are hemolysins? |
1. Staph. aureus 2. Strep. Pyogenes called streptolysin O |
The endotoxin, LPS. are usually capable of producing what general systematic effects? |
1. Fever 2. Shock 3. Blood coagulation 4. Weakness 5. Diarrhea 6. Inflammation 7. Intestinal hemorrhage 8. Fibrinolysis |
What are the two factors of the endotoxin LPS? |
1. Massive release of chemokinese 2. Massive non-specific B cell response |