Ch 12- Drugs, Microbes, Host- The elements of chemotherapy
Reverse transcriptase is a retroviral enzyme that does which of the following?
Converts RNA to DNA
True or False: Drug resistance only arises from an organism gaining the genetic information for the resistance from another organism.
False
True or False: The most effective drugs that treat infections caused by flukes, tapeworms, and roundworms eradicate the adult stages of the organisms.
False They typically block metabolism at all stages of the life cycle rather than eradicate the adult worms.
Amphotericin B is considered highly versatile in that it is effective in treating most infections caused by which of the following?
Fungi
Which of the following bacterial are normally NOT tested for drug susceptibility?
Group A streptococci
Which of the following is NOT a side effect associated with antimicrobial drugs?
Host cell metabolism of drug
Which of the following are the 3 factors that should be known before selecting an antimicrobial drug?
- The overall health of the patient - The sensitivity of the infecting agent. - The nature of the infecting agent
Direct examination of the body fluids, sputum, and stool can provide a rapid detection method for which of the following?
- bacteria - fungi
Which term describes the process of some microbes dying while others live in the presence of antimicrobial agents?
Natural selection
The tetracyclines bind to which of the following structures?
Ribosome
Tetracycline is an example of which type of drug? (narrow, limited, visible, broad)
broad spectrum
Use of which type of antibiotic can have far reaching effects on beneficial resident species?
broad-spectrum
The tolerance of an antimicrobial agent at a level which normally be inhibitory is called which of the following?
drug resistance
True or False: Natural Selection for drug-resistant forms of bacteria is rare.
false
Interferon is produced primarily by _______ and ______ in response to various immune stimuli.
fibroblasts and leukocytes
_______ analogs are structurally similar to the natural substrate and compete with it for the active site on the enzyme.
metabolic
The most effective drugs used to treat infections caused by flukes, tapeworms, and roundworms inhibit _______ at all stages of the life cycle rather than eradicating the adult worms.
metabolism
Drug therapy may fail because the infection is caused by a _______ culture (more than one species)
mixed
Drug resistance occurs with spontaneous ________ or gene transfer from another species.
mutations
Bacitracin is an antibiotic with which spectra of activity?
narrow
Bacitracin is antibiotic with which spectra of activity? (visible, narrow, selective, broad)
narrow
An antibiotic that is only effective against a limited array of different microbes is called a _________ spectrum antibiotic.
narrow or limited
Which term describes the process of some microbes dying while others live in the presence of antimicrobial agents?
natural selection
The outer membrane of some Gram- __________ bacteria act as natural barriers to some drugs.
negative
If the bacterium causing a sore throat is Streptococcus pyogenes, a physician can normally prescribe the antibiotic,
penicillin
The cell walls of most bacteria are composed primarily of which of the following?
peptidoglycan
Tetracyclines inhibit which of the following?
protein synthesis
Synercid binds to ribosomes inhibiting the process of ________
protein synthesis or translation, or peptide transfer or elongation
A viral enzyme that converts single-stranded RNA into double-stranded DNA is called
reverse transcriptase
Polymyxin B and E are toxic to which organ? (heart, kidneys, brain, lungs)
kidneys
Synercid is effective against members of which genera? - Proteus - Enterobacter - Staphylococcus - Streptococcus - Pseudomonas - Enterococcus
- Staphylococcus - Streptococcus - Enterococcus
Which two semisynthetic penicillins can be used against Gram-negative bacteria?
- Amoxicillin - Ampicillin
Which of the following are quinolones?
- Norfloxacin - Ciprofloxacin
When these 2 drugs are used in combination nephrotoxic effects are increased.
- Penicillins - Cephalosporins
Which of the following bacteria are routinely tested for drug susceptibility?
- Staphylococcus sp. - Aerobic Gram-negative enteric bacilli - Enterococcus faecalis
Which of the following are side effects associated with antimicrobial drugs? - disruption of normal microflora - allergic reactions - damage to host tissues due to toxicity - host cell metabolism of drug
- disruption of normal microflora - allergic reactions - damage to host tissues due to toxicity
Which groups of people may have greater risks to antimicrobials?
- elderly - pregnant women - infants
Approximately what percent of infections involve biofilms?
60%
The ending -floxacin is used for which category of drugs? (Quinolones, Aminoglycosides, Syntheti drugs, Tetracyclines)
Quinolones
What is the overall goal of antimicrobial chemotherapy?
To destroy the infective agent without harming the patient
True or False: Microorganisms that produce antibiotics in their natural habitat may have a selective advantage over neighboring microbes.
True
Which of the following is a hypersensitive response to a particular substance by the immune system?
allergy
Which of the following is a substance produced by natural metabolic processes of some microorganisms that can inhibit or kill other microorganisms? (antibiotic, antithesis, antibody, antigen)
antibiotic
Which of the following is a substance produced by natural metabolic processes of some microorganisms that can inhibit or kill other microorganisms?
antibiotics
__________ chemotherapy is the use of chemotherapeutic drugs to control infections and diseases caused by many types of microorganisms.
antimicrobial
Which "formation" is produced by some microbes which in turn makes them resistant to some antimicrobial compounds and the shear force of moving liquids?
biofilm
An antibiotic that is effective against a wide variety of microbial types is called a __________ spectrum antibiotic.
broad
An antibiotic that is effective against a wide variety of microbial types is called a _______ spectrum antibiotic
broad or extended
Which of the following structures in bacteria protect the cell from lysis (rupture) in hypotonic environments? (cell membrane, fimbriae, glycocalyx, cell wall, nucleoid)
cell wall
_________ is another name for polymyxin E.
colistin
Which type of inhibition of an enzyme occurs when the enzyme is blocked from action after a substance that mimics the normal substrate binds to the active site? (feedback, competitive, noncompetitive, oxidative)
competitive
The inability of a drug to _________ into a body compartment, such as the brain or joints, will render the drug ineffective.
diffuse
An allergy is caused by a hypersensitive response from which system?
immune
Which of the following is a normal human glycoprotein produced in response to immune stimuli and can be used therapeutically to fight viruses and cancer?
interferon
Nephrotoxic drugs are toxic to which of the following?
kidneys
_________ penicillins are drugs that, after being naturally produced by bacteria, are chemically modified in the laboratory.
semisynthetic
When antimicrobial therapy destroys beneficial resident microbes and allows an overgrowth of drug-resistant microorganisms it is called: focal infection, biofilm; superinfection; primary infection; secondary infection
superinfection
Amphotericin B is one of the few drugs that can be injected to treat ______ fungal infections such as cryptococcus meningitis.
systemic
True or False: Most tissues are susceptible to adverse effects caused by the use of antimicrobial therapy.
true
True or False: Most tissues are susceptible to adverse effects caused by the use of the antimicrobial therapy.
true
True or False: The nature and sensitivity of the microorganism need to be considered before antimicrobial treatment begins.
true