Exam 2 Review Flashcards
Bacterial resistance due to drug-inactivating enzymes is important for all of the following antibiotics except…
a. Penicillin G
b. Ampicillin
c. Gentamycin
d. Tetracyclin
e. Cephalexin
D - due to decreased uptake or active transport out of the bacterial cell
The fluoroquinolones, enrofloxaxin, and marbofloxacin…
a. have an antibacterial spectrum limited to G- bacteria, especially anaerobes
b. are used primarily for enteric infections since they are no absorbed from the gut
c. are useful for respiratory, skin, and urinary tract infections in puppies
d. are bactericidal via inhibition of DNA gyrase
D
Considering the pharmacology of Penicillin G and the first-generation cephalosporins, all of the following are correct, EXCEPT…
a. inhibit peptidoglycan cross-linking in the third stage of bacterial cell wall synthesis
b. resistance is most likely due to beta-lactamase production
c. tissue penetration of cephalosporins is superior to Penicillin G and are prefered for antibiotic prophylaxis before surgery
d. eliminated primarily by hepatic metabolism and biliary excretion of conjugated drug
e. nephrotoxicity is more likely to occur with high or prolonged dosage of cephalosporins
D - eliminated by renal glomerular filtration
Two semisynthetic penicillins effective against Pseudomonas spp. are…
a. methicillin and ampicillin
b. ampicillin and amoxicillin
c. amoxicillin and ticarcillin
d. ticarcillin and piperacillin
e. ticarcillin and oxacillin
D
The aminoglycoside antibiotics such as amikacin and gentamicin…
a. are lipid soluble and distribute widely to tissues including the CNS
b. are not effective against G- anaerobes because their uptake is oxygen-linked
c. are bacteriostatic at therapeutic concentrations
d. are well-absorbed orally if they are enteric-coated to protect them from gastric acids
B
Adverse reactions to the aminoglycoside antibiotics include all of the following except…
a. neuromuscular blockade
b. myelosuppression and anemia
c. nephrotoxicity
d. ototoxicity
B
Tetracyclines are broad-spectrum and bacteriostatic by a mechanism of action involving…
a. binding to the 30S ribosome to inhibit the addition of amino acids to the growing peptide chain
b. binding to the phospholipids in bacterial cell membranes to increase permeability
c. binding to the 50S ribosome to inhibit peptidyl transferase
d. inhibition of DNA gyrase
A
Tylosin…
a. inhibits the first step of cell wall synthesis and is bactericidal
b. may produce anemia by blocking iron uptake in erythroblasts
c. antibacterial spectrum includes mycoplasma
d. is usually effective in organisms resistant to erythromycin
C - is a macrolide
An antibiotic combined with erythromycin for treating Rhodococcus equi infections is foals is…
a. spectinomycin
b. vancomycin
c. rifampin
d. tylosin
C
Weekly monitoring of renal function is necessary in antifungal therapy with…
a. amphotericin B
b. ketoconazole
c. flucytosine
d. griseofulvin
A
All of the following statements concerning griseofulvin are true except…
a. oral absorption is increased by dietary fats
b. distribution is to keratin precursor cells
c. its action is rapid and fungicidal
d. it inhibits mitosis in dermatophytes
C
All of the following statements regarding ketoconazole are true except…
a. it is more effective than flucytosine for meningeal cryptococcosis since it penetrates the CNS more completely
b. it inhibits ergosterol synthesized in both systemic mycotic infections and candidiasis
c. cortisol and testosterone synthesis in mammals is inhibited at high doses
d. it must be administered for 3-6 months in therapy for systemic mycoses
A - flucytosine penetrates CNS well
Amprolium is approved for the prevention of _________ in growing chickens, turkeys, and laying hens.
a. Cryptosporidiosis
b. Coccidiosis
c. Trichomoniasis
B
BZDs and pro-BZDs have their pharmacological activity based on….
a. binding to sodium channels
b. binding to beta-tubulin subunits
c. binding to GABA-gated chloride channels
d. binding to nicotinic cholinergic receptors
B
True or false: When using antiparasitic drugs that interfere with neurotransmission of parasites, it is important to select agent that mimic inhibitory transmitters.
TRUE
