Antimicrobial drugs
_____ ______ Drug kills pathogens without
damaging the host
Selective toxicity
Interferons do what?
are small proteins that prevent viral multiplication by stimulating antiviral proteins in uninfected cells
______ is he destruction or removal of vegetative pathogens but not bacterial endospores. Usually used only on inanimate objects
disinfection
______ _______ cause disease only in a compromised host
Opportunistic Pathogens
How do normal microbiota protect the host
– Competing for nutrients
– Producing substances harmful to invading
microbes
– Affecting pH and available oxygen
Human Microbiome
Describe the difference between broad and narrow spectrum antibiotics
Broad spectrum kills a wide variety of microbes while narrow spectrum kills only certain types of microbes
Describe some misuses of antibiotics that create resistant pathogens
• Using outdated or weakened antibiotics
• Using antibiotics for the common cold and other
inappropriate conditions
• Using antibiotics in animal feed
• Using someone else's leftover prescription
• Failing complete the prescribed regimen
Describe pasteurization, is this a process of sterilization?
involves heating a particular food (such
as milk) to a moderately high temperature long enough to kill harmful bacteria, No it is not sterilization
Describe the process of Koch's Postulates
2. Microbe is isolated then grown in pure culture
3. When the microbe is introduced into a healthy individual, the same disease occurs
4. The same strain is obtained from the newly infected individual
What are nosocomial infections
Acquired while receiving treatment in a health care facility
What do Quinolones do
inhibit DNA synthesis by targeting topoisomerases, such as DNA gyrase, which introduce negative supercoils into DNA ahead of replication
forks
______ bacterial enzyme that destroys natural penicillins
What process is used to preserve the growth of bacteria such as mesophiles?
Refrigeration, slows the growth of bacteria
What are some issues with Koch's Postulates?
• asymptomatic carriers
• lack of animal model
• pathogens unculturable in lab
• mixed species infections
Describe the difference between Standard and Transmission-based precaution
Standard:basic, minimum practices
Transmission-based precaution:supplemental
to standard precautions; designed for known or
suspected infections
Contact precautions
Droplet precautions
Airborne precautions
Polymyxin B does what?
Binds membrane of Gram - cells, Alters permeability, Leads to leakage of cell and cell death
Mechanisms of Antibiotic Resistance?
Mechanism 1: alter targer
Mechanism 2: Degrade antibiotic
Mechanism 3: modify antibiotic
Mechanism 4: pump antibiotic out of the cell
Describe osmotic pressure as a way to preserve food, is this a sterilizing technique?
Adding large amounts of salt or sugar to foods creates a hypertonic environment for bacteria, causing plasmolysis, It is never a sterilizing technique
Should infectious and therapeutic dose be high or low?
Both should be high
How can we reduce the number of pathogens?
– Handwashing
– Disinfecting tubs used to bathe patients
– Cleaning instruments scrupulously
– Using disposable bandages and intubatio
Why is it important to continue to take antibiotics after they pass the MIC Line?
Once the drug passes the MIC line it is now not killing off pathogens and you would need to take more of the antibiotic to make it affective again
Steps of developing antibiotic resistance
1. harmless drug resistant microbe and harmful microbe
2. conjugation between both
3. harmful drug resistant microbe creates resistant colonies
What is used to killed endospores?
High heat and pressure such as an autoclave
______ _______ short period after incubation; early, mild symptom
Prodromal period
_____ _____ an individual whose resistance
to infection is impaired by disease, therapy, or burn
Compromised host