• Biomolecules & Therapeutics
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• 제3권4호
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• pp.322-326
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• 1995

General pharmacology of LB20304, a quinolone antibiotic, were examined in terms of general behaviour, cardiovascular, and central nervous system. LB20304 at oral dose of 2,000 mg/kg did not induce significant behavioural changes in mice. In contrast with ciprofloxacin, LB20304 at dose of 20 mg/kg, iv. did not show any observable effects on the blood pressure in rats. Displacement of [$^3$H]muscimol binding to the rat brain synaptic membranes was measured. LB20304 was shown to be about five times less potent than ciprofloxacin in specific GABA receptor binding. Drug interaction between LB20304 and 4-biphenyl acetic acid, an active metabolite of fenbufen, was assessed in mice by measuring convulsion and/or subsequent death. A single oral pretreatment with 4-BPA at 400 mg/kg increased the incidence of convulsion and death after oral administration of ciprofloxacin at the doses of 25, 50, and 100 from zero of five to three of five, two of five, and four of five, respectively, whereas LB20304 alone or combination with 4-BPA caused neither convulsions nor death at the doses of 12.5, 25, 50, and 100 mg/kg, respectively. Quinolones-induced epileptogenic activities were assessed by a direct intracerebral injection of test articles. The CD$_{50}$ values (nmole) are as follows; 169.47, 35.36, 105.29, and 88.67 for LB20304, ciprofloxacin, of loxacin, and lomefloxacin, respectively. From these data, LB 20304 at therapeutic doses seems to be much more safe than any other quinolones tested.d.

• Journal of Microbiology
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• 제44권6호
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• pp.680-684
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• 2006

Twenty isolates resistant to seven quinolones were isolated from major rivers in Korea. All isolates had three mutations, Ser83$\rightarrow$Leu and Asp87$\rightarrow$Asn in GyrA and Ser80$\rightarrow$Ile or Ser80$\rightarrow$Arg in ParC and three isolates had an additional mutation Glu84$\rightarrow$Gly or Glu84$\rightarrow$Val in ParC. In addition, a clonal spread was not found in these isolates.

• Journal of Microbiology
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• 제45권6호
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• pp.590-592
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• 2007

We report the isolation of Salmonella enterica serotype Typhimurium phage type DT104 (CCARM 8104) from swine in Korea. The CCARM 8104 isolate was resistant to nalidixic acid and showed reduced susceptibility to quinolones. The CCARM 8104 isolate had a missense mutation, Asp87Asn, in the quinolone resistance-determining region in gyrA and produced PSE-1. The CCARM 8104 isolate carried two different class 1 integrons, and the PSE-1 ${\beta}$-lactamase gene was inserted into a 1,200 bp class 1 integron. The presence of DT104 with pse-1 in an integron located in a plasmid and reduced susceptibility to quinolone in swine pose a significant threat of possible horizontal spread between swine and humans.

• Toxicological Research
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• 제8권1호
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• pp.63-70
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• 1992

The present study was performed to evaluate whether the application of Fenbufen is reasonable for predicting the convulsive liability of the quinolone derivatives and to examine whether pentylenetetrazole (PTZ) can be used as a screening tool for their Central Nervous System (CNS) toxic pontential. The convulsive activity of the quinolones was markedly potentiated by the pretreatment of Fenbufen. In combination with Fenbufen, enoxacin (ENX), norfloxacin (XFLX), and ciprofloxacin (CPFX) provoked convlusions and subsequent death at the intravenous doses of 0.5mg/kg, 10mg/kg, and 40mg/kg, respectively, whereas ofloxacin (OFLX) and pefloxacin (PFLX) did not induce convulsions and death even at a relatively high dose of 100mg/kg iv.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.57-63
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• 1997

Animal and clinical investigations have shown that fluoroquinolones, new quinolone antibacterial agents (NQs), are well absorbed across the intestinal tract, with a bioavailability of 60-90% after oral administration. Although some types of carrier-mediated intestinal transport mechanisms have been reported for enoxacin (ENX), ofloxacin (OFLX) and sparfloxacin (SPFX), recent results using a human intestinal epithelial cell line, Caco-2, indicated a passive or nonsaturable transport of SPFX, one of the most hydrophobic NQs. The mechanism underlying the intestinal absorption of NQs is still largely unknown. The distribution of NQs into peripheral tissues including erythrocytes is very rapid and their tissue-to-plasma concentration ratios (Kp) are considerably larger than those of inulin (an extracellular fluid space marker), in spite of almost complete ionization of NQs at the physiological pH. Our findings suggest that OFLX and lomefloxacin (LFLX) are taken up by rat erythrocytes via a transport system common to that of a water-soluble vitamin, nicotinic acid.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.12-12
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• 1997

CFC-222 is a novel fluoroqinolone antibacterial agent synthesized and under development by the Cheil Jedang Corporation, Korea. CFC-222 exerts the antibacterial activity by inhibition of bacterial DNA gyrase leading to bactericidal action. In in vitro and in vivo preclinical testing, CFC-222 has been shown to possess a broad spectrum of antibacterial activity. In particular CFC-222 is very potent against Gram-positive bacteria such as Staphylococcus spp., Streptocuccus spp. (in particular penicillin G-resistant and -susceptible S. pneumoniae) and Enterococcus spp. when compared to other quinolones (ciprofloxacin, ofloxacin or lomefloxacin). CFC-222 also showed potent activity against the methicillin resistant clinical isolates of S. aureus (MRSA). Against Gram-negative bacteria (E. coli, Pseudomonas and Sarcina) the activity of CFC-222 was slightly weaker than that of ciprofloxacin, but was more potent than that of ofloxacin or lomefloxacin. In urinary systemic infections caused by both Gram-positive and -negative bacteria, CFC-222 demonstrated a potent therapeutic efficacy in particular against Cram-positive bacteria S. aureus, S. pyrogen 203 and S. pneumonia TypeIII.

• Biomolecules & Therapeutics
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• 제7권2호
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• pp.164-169
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• 1999

The synthesis and antimicrobial activity of N-substituted glycol derivatives of Norfloxacin were described. Norfloxacin was treated with chloroacetyl chloride to yield chloroacetyl norfloxacin (1). This compounds was reacted with alkyldiamines to afford bivalent ligand quinolone carboxylic acids (2-6), which was added to pivaloyloxymethyl chloride to give bivalent ligand pivaloyloxymethyl quinolone carboxylates (7-11). Chloroacetyl norfloxacin (1) treated with alkylamines to obtain monovalent ligand quinolone carboxylic acids (12-15), which was reacted with pivaloyloxymethyl chloride to get monovalent ligand pivaloyloxymethyl quinolone carboxylates (16-19). Free carboxylic quinolones (2-6, 12-15) showed little stronger activities to their pivaloyloxymethyl esters (7-11, 16-19). In monovalent ligand quinolone analogues, longer a1kyl chain com-pounds showed stronger activities than shorter one.

• Journal of Microbiology and Biotechnology
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• 제15권2호
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• pp.421-424
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• 2005

Effect of antibiotics belonging to three different groups, including third generation cephalosporins, aminoglycosides, and quinolones, on the outer membrane protein (OMP) profile of Klebsiella pneumoniae was examined. It was found that a new OMP (porins) of 40 kDa molecular mass was expressed in Klebsiella pneumoniae, when grown in the presence of ceftazidime, whereas new proteins with 30 kDa and 22 kDa masses were detected in the presence of ofloxacin. The immunoblot analysis showed that the new proteins of 40 kDa and 30 kDa molecular masses were expressed on the outer envelope, when being exposed to antibiotics ceftazidime and ofloxacin, respectively. This finding is important, as the outer surface comes in contact with the immune system, and therefore may have a bearing on the outcome of the disease.

• 한국동물위생학회지
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• 제33권1호
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• pp.23-27
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• 2010

This survey was performed to investigate the seroprevalence of antibodies to Brucella canis in dogs from public animal shelters and breeding kennels in Incheon. A total of 402 dogs selected randomly were tested serologically by using immunochromatographic antibody test kit. None of 289 dogs in public animal shelters were sero-positive and 10 (8.9%) of 113 dogs in breeding kennels were sero-positive. 5 (4.4%) strains of Brucella canis were isolated from 10 sero-positive dogs' blood. Antimicrobial susceptibility test was carried out by Disk diffusion method. They were susceptible to tetracyclines, quinolones, aminoglycosides and combination amoxicillin with clavulanic acid.

• 생명과학회지
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• 제13권6호
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• pp.943-949
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• 2003

7번 위치에 하롤겐이 치환된 여로종류의 퀴놀론 모핵과 시스 또는 트란스-3-아미노-4-메틸오메틸피롤리딘을 반응시켜 7-(시스 또는 트란스-3-아미노-4-메틸티오메틸피롤리디닐) 퀴롤론-3-카르복실산의 신규 항균제를 합성하였다. 새롭게 합성된 퀴놀론의 약효는 그람양성균에 대해 대조물질인 시프로플로삭신보다 매우 탁월하였고, 녹농균이외의 그람음성균에 대해서도 대조물질과 거의 유사하였다. 그리고 임상에서 문제가 되고 있는 메티실린 내성 포도상구균(MRSA)에 대한 신규 퀴놀론의 약효는 더욱더 향상되어진 것으로 나타났다.