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Journal of Chromatography. A Dec 2002A reversed-phase high-performance liquid chromatographic method with tandem mass-spectrometric detection was developed and validated for the simultaneous analysis of...
Determination of quinolones and fluoroquinolones in fish tissue and seafood by high-performance liquid chromatography with electrospray ionisation tandem mass spectrometric detection.
A reversed-phase high-performance liquid chromatographic method with tandem mass-spectrometric detection was developed and validated for the simultaneous analysis of eight quinolones and fluoroquinolones (oxolinic acid, flumequine, piromidic acid, enrofloxacin, ciprofloxacin, danofloxacin, sarafloxacin and orbifloxacin) in trout tissue, prawns and abalone. The analytes were extracted from homogenised tissue using acetonitrile and the extracts subjected to an automated two-stage solid-phase extraction process involving polymeric reversed-phase and anion-exchange cartridges. Good recoveries were obtained for all analytes and the limit of quantification was 5 microg/kg (10 microg/kg for ciprofloxacin). The limit of detection was 1-3 microg/kg, depending on the analyte and matrix. Confirmation of the identity of a residue was achieved by further tandem mass-spectrometric analysis. A procedure for estimating the uncertainty associated with the measurement is presented.
Topics: 4-Quinolones; Animals; Anti-Infective Agents; Calibration; Chromatography, High Pressure Liquid; Fishes; Fluoroquinolones; Reproducibility of Results; Seafood; Sensitivity and Specificity; Spectrometry, Mass, Electrospray Ionization
PubMed: 12489859
DOI: 10.1016/s0021-9673(02)01407-3 -
Microbiologica Jul 1987The in vitro attachment of 49 Proteus spp. to human urinary tract epithelial cells was determined. The antibacterial spectrum to all species of the Proteus isolates from...
The in vitro attachment of 49 Proteus spp. to human urinary tract epithelial cells was determined. The antibacterial spectrum to all species of the Proteus isolates from hospitalized patients was measured against the most common antibiotics (Amikacin, Cefamandole, Cefoxitin, Ceftriaxone, Cephalothin, Kanamycin, Nalidixic acid, Oxolinic acid, Pipemidic acid, Piromidic acid, Tobramycin). 18 of them were multiresistant and the other 31 expressed susceptibility to the above antibiotics. Bacterial adherence to uroepithelial cells was studied in relation to susceptibility on antibiotics. The mean of bacteria per cell for the 31 strains grouped as susceptible was 20.2 and for the 18 strains grouped as resistant the mean was 55.1. Our results demonstrate a significant relationship between bacterial adhesion and antibiotic susceptibility pattern by Student's t test (P less than 0.01).
Topics: Adult; Aminoglycosides; Anti-Bacterial Agents; Anti-Infective Agents, Urinary; Bacterial Adhesion; Cephalosporins; Drug Resistance, Microbial; Epithelial Cells; Epithelium; Female; Humans; Proteus; Proteus Infections; Urinary Tract; Urinary Tract Infections
PubMed: 3626886
DOI: No ID Found -
Il Farmaco; Edizione Scientifica Apr 1985The synthesis of 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1H-pyrrol-1-yl)quinoline-3-carboxy lic acid, a new fluorinated high broad-spectrum antibacterial agent related to...
1-Ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1H-pyrrol-1-yl)-quinoline-3-carb oxylic acid, a new fluorinated compounds of oxacin family with high broad-spectrum antibacterial activities.
The synthesis of 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1H-pyrrol-1-yl)quinoline-3-carboxy lic acid, a new fluorinated high broad-spectrum antibacterial agent related to nalidixic acid is described. The title compound has been prepared by the reaction of 4-fluoro-3-(1H-pyrrol-1-yl)aniline with diethyl ethoxymethylenemalonate, cyclization of the malonate obtained to the quinolinecarboxylate ester, ethylation of the ester, followed by hydrolysis with aqueous sodium hydroxide. The new derivative proved very active against both gram-positive and gram-negative bacteria. Its activities in comparison with those of nalidixic acid, pipemidic acid, piromidic acid and enoxacin were found to be greatly superior with regard to the unfluorinated compounds and somewhat superior also to enoxacin. The known 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(pyrrolidin-1-yl)quinoline-3- carboxylic acid, here prepared by catalytic hydrogenation of the pyrrole moiety of the title compound, has been found to be less active as an antibacterial agent.
Topics: Anti-Bacterial Agents; Chemical Phenomena; Chemistry; Ciprofloxacin; Enterobacteriaceae; Fluoroquinolones; Gram-Positive Bacteria; Microbial Sensitivity Tests; Proteus; Pseudomonas aeruginosa; Quinolines
PubMed: 3926533
DOI: No ID Found -
Deutsche Medizinische Wochenschrift... May 1983Within 30 months the diagnosis of drug-induced acute interstitial nephritis was made in ten patients with acute onset of renal failure of clinically unknown cause.... (Comparative Study)
Comparative Study
Within 30 months the diagnosis of drug-induced acute interstitial nephritis was made in ten patients with acute onset of renal failure of clinically unknown cause. Allergenic substances were discovered to be antibiotics, pyrazol and indol derivatives, piromidic acid and chlorazanil. In contrast to the known course of methicillin nephritis the clinical signs were undramatic. Non-oliguric renal failure predominated, sometimes with leucocyturia, microhaematuria and moderate proteinuria. Intermittent haemodialysis was necessary in half the cases. Renal function developed favourably without further specific treatment, however, plasma creatinine did not return to normal levels in most cases. Percutaneous renal biopsy was the definitive diagnostic step. Indications for biopsy in cases of unclear acute renal failure should thus be handled liberally in order to prevent continued drug exposure with the danger of irreversible renal failure.
Topics: Acute Disease; Adolescent; Adult; Aged; Anti-Bacterial Agents; Chlorobenzenes; Female; Humans; Indoles; Male; Methicillin; Middle Aged; Nephritis, Interstitial; Pyrazoles; Triazines
PubMed: 6840011
DOI: 10.1055/s-2008-1069641 -
Journal of Chromatography Aug 1989A simple and rapid method for the determination of residual pyridonecarboxylic acid antibacterials (PCAs) (oxolinic acid, nalidixic acid and piromidic acid) in fish was...
Improvement of chemical analysis of antibiotics. XVI. Simple and rapid determination of residual pyridonecarboxylic acid antibacterials in fish using a prepacked amino cartridge.
A simple and rapid method for the determination of residual pyridonecarboxylic acid antibacterials (PCAs) (oxolinic acid, nalidixic acid and piromidic acid) in fish was developed using a combination of high-performance liquid chromatography (HPLC) and clean-up with an amino-type prepacked cartridge. PCAs were extracted with n-hexane-ethyl acetate (1:3) and the extract was applied to a Baker 10 amino cartridge. PCAs were eluted from the cartridge with acetonitrile-methanol-0.01 M aqueous oxalic acid solution (pH 3.0) (3:1:6) and were determined by HPLC. The separations were performed on Nucleosil 3C18 (3 microns, 75 x 4.6 mm I.D.) using a mobile phase containing oxalic acid. The recoveries of PCAs from various fishes fortified at the level of 1.0 ppm were 77.1-95.5%, and the detection limits were 0.05 ppm. The analytical time per sample was less than 30 min.
Topics: Animals; Anti-Infective Agents; Chromatography, High Pressure Liquid; Drug Residues; Fishes; Food Analysis; Nalidixic Acid; Oxolinic Acid; Piromidic Acid
PubMed: 2808587
DOI: 10.1016/s0021-9673(01)89648-5 -
Il Farmaco; Edizione Scientifica Nov 1984A new analog of nalidixic acid, 1-ethyl-1,4-dihydro-4-oxo--7-(1-pyrryl)quinoline-3-carboxylic acid, is described. When tested against gram-positive and gram-negative...
A new analog of nalidixic acid, 1-ethyl-1,4-dihydro-4-oxo--7-(1-pyrryl)quinoline-3-carboxylic acid, is described. When tested against gram-positive and gram-negative bacteria this compound showed many significant activities and was more active than nalidixic, piromidic and pipemidic acids. On the contrary its 6-chloro- and 6-methylderivatives lack antimicrobial activities. All new compounds here described were synthesized by standard procedures via Gould-Jacobs reaction.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Antifungal Agents; Blastomyces; Chemical Phenomena; Chemistry; Enterobacteriaceae; Gram-Positive Bacteria; Microbial Sensitivity Tests; Nalidixic Acid; Proteus; Pseudomonas aeruginosa
PubMed: 6440810
DOI: No ID Found -
Annali Dell'Istituto Superiore Di Sanita 1982
Comparative Study
Topics: Bacteria; Hydrogen-Ion Concentration; Microbial Sensitivity Tests; Nalidixic Acid; Nicotinic Acids; Pipemidic Acid; Piromidic Acid
PubMed: 7187832
DOI: No ID Found -
Journal of Chromatography. B,... Jun 2000The potential of capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MEKC) have been investigated for the separation and...
The potential of capillary zone electrophoresis (CZE) and micellar electrokinetic capillary chromatography (MEKC) have been investigated for the separation and quantitative determination of 10 quinolone antibiotics. The influence of different conditions, such as the buffer and pH of the electrolyte, the surfactant and the ion-pairing agents added to the electrolyte and the organic modifier were studied. A buffer consisting of 40 mM sodium tetraborate at pH 8.1 containing 10% (v/v) methanol was found to be a highly efficient electrophoretic system for separating lomefloxacin, enoxacin, norfloxacin, pipemidic acid, ofloxacin, piromidic acid, flumequine, oxolinic acid, cinoxacin and nalidixic acid. A solid-phase extraction method to remove the sample matrix (pig plasma samples) was developed on a C(18) cartridge using a mixture of methanol-water (70:30, v/v). The method is specific and reproducible and mean recoveries were in the range 94.0+/-4.2% and 123.3+/-4.1% for pig plasma samples over the range used. A linear relationship between concentration and peak area for each compound in pig plasma samples was obtained in the concentration range 5-20 mg l(-1) and detection limits were between 1.1 and 2.4 mg l(-1).
Topics: 4-Quinolones; Animals; Anti-Infective Agents; Electrophoresis, Capillary; Reproducibility of Results; Sensitivity and Specificity; Swine
PubMed: 10901130
DOI: 10.1016/s0378-4347(00)00169-9 -
Journal of Chromatography. A Nov 1997An HPLC method with ultraviolet and fluorimetric detection has been established for the separation and determination of six quinolonic and cinolonic antibiotics. A... (Comparative Study)
Comparative Study
Determination of the chemotherapeutic quinolonic and cinolonic derivatives in urine by high-performance liquid chromatography with ultraviolet and fluorescence detection in series.
An HPLC method with ultraviolet and fluorimetric detection has been established for the separation and determination of six quinolonic and cinolonic antibiotics. A Nova-Pak C18 column (150 x 3.9 mm) and a Waters 486 UV and a Waters 470 fluorescence detector have been used. The influence of variables such as mobile-phase composition and flow-rate, has been studied. An acetonitrile-aqueous solution of oxalic acid 4x10(-4) M (28:72, v/v) has been selected as optimum. The wavelength for the photometric detection of the six antibiotics was 265 nm. For the fluorimetric detection two pairs of excitation/emission wavelengths, 260/360 or 270/440 nm, were selected for the determination of nalidixic acid, 7-hydroxymethylnalidixic acid and oxolinic acid, and for the determination of pipemidic acid and cinoxacin, respectively. The analytical parameters and detection and quantification limits of the method have been determined. The proposed method has been applied for the determination of the six compounds in urine, applying different procedures depending on their concentration, the results being very acceptable.
Topics: Anti-Infective Agents; Chromatography, High Pressure Liquid; Cinoxacin; Humans; Nalidixic Acid; Oxolinic Acid; Pipemidic Acid; Piromidic Acid; Sensitivity and Specificity; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet
PubMed: 9445649
DOI: 10.1016/s0021-9673(97)00630-4 -
Journal of Microbiological Methods Dec 2000A microscopy-based method was developed to distinguish naphthalene-degrading bacteria within the microbial community of a coal tar-contaminated groundwater system. Pure...
A microscopy-based method was developed to distinguish naphthalene-degrading bacteria within the microbial community of a coal tar-contaminated groundwater system. Pure cultures of Pseudomonas putida NCIB 9816-4 were used to develop the substrate responsive-direct viable count (SR-DVC) method. Cells were concentrated on membrane filters, placed on agar plates of Stanier's minimal basal salts media containing antibiotics (nalidixic acid, piromidic acid, pipemidic acid, and cephalexin), and exposed to vapors of naphthalene. Following brief incubation, samples were fixed in 2% formaldehyde and examined by epifluorescent microscopy. Pure cultures displayed the expected cell elongation response to the SR-DVC assay and required a minimum incubation time of 9 h for differentiation of elongated cells. When applied to groundwater samples from the study site, naphthalene responsive cells in the groundwater community were easily distinguished from unresponsive cells and debris (350+/-180 substrate responsive cells/ml, relative to negative controls with no added growth substrate). In an attempt to reduce background counts of elongated bacteria and fungi, the SR-DVC procedure was modified by adding a wash step prior to incubation and a fungal inhibitor, cyclohexamide, to the plates. When groundwater samples were subjected to the modified procedure, only cells in washed samples showed a significant response to naphthalene (150+/-25 cells/ml), indicating the presence of inhibitory substances in the groundwater. Variations in response of the groundwater microbial community to the two SR-DVC procedures suggest that subsurface conditions (microbial and chemical composition) vary temporally. SR-DVC allows the phenotypes of individual naturally occurring cells to be assessed.
Topics: Bacteria; Bacteriological Techniques; Biodegradation, Environmental; Coal Tar; Ecology; Naphthalenes; Pseudomonas putida; Water Pollutants, Chemical
PubMed: 11121606
DOI: 10.1016/s0167-7012(00)00210-4