• Korean Journal of Veterinary Research
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• v.34 no.1
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• pp.153-163
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• 1994

A study on quinolone antibacterial (pefloxacin methanesulfonate) was performed to use for the drug of fisheries. Petloxacin was proved excellent in antibacterial activity and resistance against fish pathogens when compared with the existing antibacterials. And any side effect was not observed during the period of indicated use. An outline of MIC(Minimal Inhibitory Concentration) was $1.6{\sim}6.4{\mu}g/ml$, $TLm_{48h}$ value were 380~420 ppm in Israeli carp(Cyprinus caprio) and 2100~2300 ppm in flounder(Paralichthys olivaceus). The residual time of fish body was less than 15 days. So we can treat some bacterial disease of fish by the dosage of 100 g/day/ton of fish body weight for 3 days and pefloxacin is thought to be used effectively and widely against most bacterial fish pathogens.

• Archives of Pharmacal Research
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• v.16 no.1
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• pp.6-12
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• 1993

To evaluate KR-10876, a new fluoroquinolone antibacterial agent, its effects on the central nervous system(CNS) were investigated in mmice as part of phamacological study, and the results were compared with those for ciprofloxacin and ofloxacin, two prototypes of quinolone antiabctrial agents. All the parameters indicative of CNS function and acute toxicity were measured by close observation of the animals at regular time intervals after oral treatment of test compounds. KR-10876 did not have any effect on the parameters measured at lower does (100, 300 mg/kg, p.o.), it caused ptosis, suppressed spontaneous locomotor activity, hypothemia, and prolonged hexobarbital-induced sleeping time. KR-10876 also had a slight effect on motor coordination only at high dose. Simialr to ciprofloxacin, KR-10876 did not protect mice from pentylenetetrazol-strychnine-, and electroshock-inducedl convulsions at doses tested. These findings demonstrate that KR-10876 affects CNS functions only at high doses. The rank order for effects is ofloxacin$\le$KR-10876>ciprofloxacin.

• Journal of the Korean Magnetic Resonance Society
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• v.6 no.1
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• pp.78-83
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• 2002

A new fluoroquinolone (DW-116) with a broad antibacterial spectrum was synthesized by introducing functional fluoropyridyl and methylpyrazine groups on N1, C7 position of quinolone moiety, respectively. $^{1}$H and $^{13}$ C NMR signal assignments and structure were completely elucidated by 2D-NMR methods. Physicochemical properties of products were also investigated. DW-116 is decomposed at 306.9$^{\circ}C$ and the decomposition starts at around 285$^{\circ}C$. The free base form is melt at 280.7$^{\circ}C$ and started to be decomposed immediately. DW-116 has two kinds of polymorphism which is important in drug action but these two plate and rod types have the same solubility in water. However the solubility is quite different in less or polar solvent. The plate type is more soluble in less polar solvent except in dichloromethane.

• Bulletin of the Korean Chemical Society
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• v.21 no.9
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• pp.849-854
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• 2000

The protonation and divalent cation complexation equilibria of several quinolone antibiotics such as nalidixic acid (NAL),flumequine (FLU), oxolinic acid (OXO), ofloxacin (OFL), norfloxacin (NOR) and enoxacin (ENO) have been examined by potentiome tric titration and spectrophotometric method. The antibacterial activity of these drugs depends upon the pH and the concentration of metal cations such as Mg2+ , Ca2+ in solu-tion. The apparent ionization constants of NAL, FLU, OXO, OFL, NOR and ENO in aqueous solution were found to be 6.33, 6.51, 6.72, 7.18, 7.26, and 7.53, respectively. In aqueous solution, NAL, FLU and OXO were found to be present mainly as two chemical species : molecularand anionic; but OFL, NOR and ENO were present mainly as three chemical species : anionic, neutral zwitterionic and cationic form, in equilibrium. The pKa1 and pKa2are found to be 6.10 and 8.28 for OFL; 6.23 and 8.55 for NOR; 6.32 and8.62 for ENO, respec-tively. The complex formation constants between OFL, NOR or FLU and some divalent cations are measured at pH 7.5. The 1 : 1 complexes are formed mainly by ion-dipole interaction. FLU has somewhat larger Kf values than OFL and NOR because its molecular size is small and the FLU is present asanionic form at pH 7.5.

• YAKHAK HOEJI
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• v.38 no.5
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• pp.586-594
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• 1994

The general pharmacological effects of DWQ-013, a new synthetic quinolone antibacterial agent, were examined on the central nervous system in experimentral animals and the following results were obtained. Drug interaction of DWQ-013 with theophylline, fenbufen and nonsteroidal antiinflammatory drugs was also examined. DWQ-013 decreased touch escape effect on the general behavior and decreased body temperature at a concentration of 1000 mg/kg in mice. But DWQ 013 had no effect on the locomotor activity, rotarod perfomance and traction test in mice. Furthermore, DWQ-013 increased pentobarbital-induced sleeping time and affected the onset time in acetic acid-induced writhing test in mice. DWQ-013 reduced onset time and death time on strychnine-induced convulsions and death time on pentylenetetrazole-induced convulsions at a concentration of 1000 mg/kg in mice. But, the drug had no effect on the electroshock. DWQ-013 did not interact with fenbufen and any other NSAIDs but it did interact with theophylline. From these results, it could be suggested that DWQ-013 had less pharmacological effect than other quinolones on the central nervous system.

• YAKHAK HOEJI
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• v.37 no.6
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• pp.638-646
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• 1993

A cepfialosporin with an aminothiazoiylmethoxyimino-type side chain at the 7 position and bicyclic quinolone dithicarbamate at the 3' position was synthesized. It has broad and potent antivacterial activity in vitro. The antibacterial spectrum reflects contributions of both the cephalosporin moiety and the quinolone moiety. Thus, this compound was named DACD implying a dualaction cephalosporin derivative. In this paper, the physicochemical proper-ties (lipid-water partition, pKa), stability and pharmacokinetics of DACD were determined and compared with cefotaxime 3'-norfloxacin dithiocarbamate (CENO). Stability tests were studied in pH 1.20, 6.80 and 8.00 buffers and in the presence of AB type human plasma, rat liver homogenate and its .betha.-lactamase. The pharmacokinetic parameters of DACD were evaluated in mice after a single intravenous dose of 40 mg/kg. The results are as follows. The lipid-water partition coefficient of DACD was higher than that of CENO. The calculated pKa values of CENO and DACD, were 6.82$\pm$0.03, 7.53$\pm$0.21, respectively. In the hydrolysis test, half-lives (t$^{1/2}$) of CENO and DACD was 66.0 hr and 80.0 hr in pH 6.80 buffer, 190 hr and 91.4 hr in pH 8.00 buffer. CENO and DACD were rapidly hydrolyzed in human plasma and in rat liver hornogenate. Half-lives (t$_{1/2}$ of CENO and DACD were 1.29 hr and 1.15 hr in hyman plasma, 0.62 hr and 0.71 hr rat liver homogenate. In $\beta$-lactamase stability test, CENO and DACD were very stable to the .betha.-lactamases obtained from three different strains. Half-life (t$_{1/2}$) and areas under the curve (AUC) in mice were 2.33 hr and 15.97 (mg.h/1), respectively.

• The Journal of Korean Obstetrics and Gynecology
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• v.25 no.3
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• pp.27-39
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• 2012

Objectives: Recently Ciprofloxacin, used in the treatment of mastitis, showed many serious side effects. The object of this study was to recognize whether TNS and KWT can be used in the treatment of mastitis by observing the in vitro antibacterial effects of TNS and KWT aqueous herbal extracts against S. aureus. Methods: Antibacterial activities of TNS and KWT aqueous extracts against S. aureus ATCC 25923 were detected using standard agar microdilution methods. In addition, the effects on the bacterial growth curve were monitored at MIC and $MIC{\times}2$ levels. The effects on the intracellular killing and bacterial invasion of individual test materials were also observed using Raw 264.6 and MCF-7. The results were compared with Ciprofloxacin, a second generation of quinolone antibiotics in the present study. Results: MIC of aqueous extracts of TNS and KWT against S. aureus were detected as ($0.313{\pm}0.107$) and ($0.137{\pm}0.053$) mg/ml, respectively. MIC of Ciprofloxacin was detected as ($0.469{\pm}0.297$) ${\mu}g/ml$ at same conditions. In addition, TNS, KWT aqueous herbal extracts and Ciprofloxacin were also showed marked dosage-dependent inhibition of bacterial growth, and dramatical inhibitions on the both intracellular killing assays and bacterial invasion using Raw 264.6 and MCF-7 cells were detected. Conclusions: The results obtained in this study suggest that TNS and KWT aqueous herbal extracts showed antibacterial effects against S. aureus, and they also showed dosage-dependent inhibitory effects on the bacterial growth. And they showed the significant intracellular killing and bacterial invasion effects. It means, KWT and TNS may show more potent anti-infectious effects against S. aureus in vivo.

• Biomolecules & Therapeutics
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• v.5 no.2
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• pp.187-193
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• 1997

The in vivo and in vivo antibacterial activity of DW-116, a newly synthesized fluoroquinolone, were compared with those of other quinolones. DW-116 exhibited more potent antibacterial activity than rufloxacin and lower activity than ofloxacin and ciprofloxacin in in vivo assay But, DW-116 particularly showed strong activity against the family of staphylococci including methicillin-sensitive staphylococcus and its activity was more active than that of ciprofloxacin. The time-kill curve studies showed rapid bactericidal activity for DW-116. The post-antibiotic effect of DW-116 was observed between 0.66 and 5 hours. The therapeutic efficacy of DW-116 against respiratory infection with P. aeruginosa was as strong as that of ciprofloxacin and its effect against urinary tract in(traction with E. coli was more effective than rufloxacin. The excellent therapeutic efficacy of DW-116 against these local infections is due to its good pharmacokinetic profiles.

• Journal of Yeungnam Medical Science
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• v.8 no.1
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• pp.53-62
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• 1991

Experiments were performed in mice(Balb/C) to support the basic efficacy of the human immunoglobulin (IgG) preparation. The antibacterial activity of IgG purified from human sera was examined with or without the quinolone agent, ciprofloxacin(CPFX), against Pseudomonas aeruginosa isolated from clinical specimens. Results were as follows: Antibacterial activities in terms of the percentage of survivors, after administration of Ps. aeruginosa into mouse intraperitoneal cavity were in the following order, single IgG group, CPFX administration after IgG pretreatment group, IgG and CPFX combined administration group and CPFX alone group. The number of living bacteria was monitored in blood and liver tissue of mice infected with Ps. aeriginosa and treated by IgG administration. The increase of living bacteria in liver was more drastic than that in blood. Leukocytosis was observed in mice injected with IgG, excluding those only with ciprofloxacin, after 8 hours of administration to see a decrease to normal number of bacteria after 18 hours. No significant difference was noticed between pretreatment group and post treatment group. In vitro susceptibility test of IgG against Ps. aeruginosa, minimal inhibitory concentration(MIC) was $250{\mu}g/ml$, resistant to IgG, regardless of a combined administration with CPFX. In vitro test revealed that the IgG itself did not have anti-Ps. aeruginosa activity.

• YAKHAK HOEJI
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• v.55 no.1
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• pp.11-15
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• 2011

Zabofloxacin is a novel broad spectrum fluoroquinolone with excellent anti-pneumococcal activity. We investigated the in vitro activity of zabofloxacin against clinical isolates of gram-positive bacteria and the in vivo activity against systemic infection in mice. Zabofloxacin was very active against gram-positive bacteria except QRSA (Quinolone-resistant S. aureus) and VRE(Vancomycin-resistant Enterococci). Especially, zabofloxacin was extremely potent against clinical isolates of Streptococci. Zabofloxacin was as active as gemifloxacin against systemic infection in mice. In view of its improved antibacterial activities against gram-positive bacteria and good pharmacokinetic profiles in animals, the clinical usefulness of zabofloxacin should be established by further studies.