Synergistic activity of 1-(1-naphthylmethyl)-piperazine with ciprofloxacin against clinically resistant Staphylococcus aureus, as determined by different methods.
OBJECTIVE
To evaluate the interaction of 1-(1-naphthylmethyl)-piperazine (NMP) and ciprofloxacin (CPFX) in vitro against fluoroquinolone (FQ)-resistant clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA).


RESULTS
The in vitro interaction of NMP and CPFX in 12 FQ-resistant clinical isolates of MRSA was assessed using a checkerboard microdilution method. In the study, a synergistic antimicrobial effect between NMP and CPFX was observed in all 12 FQ-resistant strains tested, as determined by the fractional inhibitory concentration index (FICI), and in 10 strains using ΔE models. No antagonistic activity was observed in any of the strains tested. These positive interactions were also confirmed using the time-killing test and agar diffusion assay for the selected strain, MRSA 1862; synergistic activity was observed when NMP was combined with the first-line antimicrobial agent CPFX against Staph. aureus.


CONCLUSIONS
Synergistic activity between NMP and CPFX against clinical isolates of FQ-resistant Staph. aureus was observed in vitro.


CONCLUSIONS
This report might provide alternative methods to reduce the resistance of Staph. aureus to CPFX.
Key Laboratory of Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Animal Science and Veterinary Medicine, Jilin University, Changchun, China.
L
L
Li
Z
Z
Li
N
N
Guo
J
J
Jin
R
R
Du
J
J
Liang
X
X
Wu
X
X
Wang
M
M
Liu
Q
Q
Jin
L
L
Yu
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002939:Ciprofloxacin / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D004357:Drug Synergism; D024841:Fluoroquinolones / Q000494:pharmacology; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects*; D010879:Piperazines / Q000737:chemistry / Q000494:pharmacology*
C511391:1-(1-naphthylmethyl)piperazine; D000900:Anti-Bacterial Agents; D024841:Fluoroquinolones; D010879:Piperazines; D002939:Ciprofloxacin