Wyniki wyszukiwania - Biblioteka Nauki

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Study on the drug–drug interaction of antituberculosis drugs — PA-824 and moxifloxacin based on pharmacokinetics in rats by LC–MS/MS

100%

Jing J. , Jia Y. , Feng T. , Xie T. , Li Z. , Hao Y. , Wang L.

Acta Chromatographica

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2019

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tom Vol. 31, no. 3

206--210

EN

A simple, rapid, and sensitive liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed and validated for the simultaneous quantitation of PA-824 and moxifloxacin in rat plasma using carbamazepine as an internal standard (IS). The sample preparation involved a one-step protein precipitation method with methanol. The separation was performed on Inertsil® ODS3 C18 column (150 mm × 4.6 mm, 5 μm) and maintained at 30 °C. The mobile phase consisted of 0.1% formic acid in acetonitrile–water (90:10 v/v) with fast isocratic elution at a flow rate of 0.6 mL/min and a run time of 10 min. A mass spectrometer was run in the positive ion electrospray ionization (ESI) mode using multiple reaction monitoring (MRM) to monitor the mass transitions. The MRM transitions were chosen to be m/z 360.1 → m/z 175.0 for PA-824, m/z 402.0 → m/z 383.9 for moxifloxacin, and m/z 237.1 → m/z 194.0 for IS. The method was fully validated in terms of selectivity, linearity, accuracy, precision, matrix effect, recovery, and stability, respectively. The method was successfully applied to drug–drug interaction (DDI) study of PA-824 and moxifloxacin in rats. The results show that the main pharmacokinetic parameters of PA-824, namely, Tmax, t1/2, and AUC(0–t), increased more in the PA-824 and moxifloxacin group than in the PA-824 group. However, there were little changes in the main pharmacokinetic parameters of moxifloxacin from single and combined groups.

2

Fast and Sensitive RP-HPLC—Fluorescence Method for the Quantitative Analysis of Moxifloxacin in Rat Plasma and Its Application to a Preclinical Pharmacokinetic Study

88%

Hurtado F. K. , Kaiser M. , Tasso L. , Costa T.

Acta Chromatographica

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2016

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tom Vol. 28, no. 2

175--191

EN

A fast, simple, and sensitive reversed-phase high-performance liquid chromatography (RP-HPLC) method has been developed and fully validated for the determination of moxifloxacin (MXF) in rat plasma. MXF and gatifloxacin (internal standard, I.S.) were extracted from plasma by single-step protein precipitation with acidified acetonitrile. Chromatographic separation was accomplished in less than 8 min on an Atlantis ® T3 column with 0.4% aqueous triethylamine–methanol–acetonitrile (60:35:5, v/v/v) solution as mobile phase. Detection was achieved by fluorescence (λexcitation = 295 nm, λemission = 500 nm), and the calibration curves were found to be linear over the plasma concentration range of 10–2,500 ng mL−1 with a mean correlation coefficient (r) of 0.9946 (n = 6). The intra- and inter-assay imprecision (% CV) was less than 2.4 and 3.3%, respectively, and the accuracy was >90%. The mean extraction recoveries for MXF and I.S. from plasma were 77 and 82%, respectively. The method was also validated for specificity, sensitivity, and stability; all the results were within the acceptable range. The proposed method was then successfully applied to the quantitative analysis of MXF in rat plasma samples, being a valuable and high-throughput assay to support ongoing pharmacokinetic studies on this promising anti-infective agent.

3

An HPLC method for the determination of moxifloxacin in breast milk by fluorimetric detection with precolumn derivatization

75%

Tekkeli S. E. , Gazioglu I. , Kiziltas M. V.

Acta Chromatographica

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2017

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tom Vol. 29, no. 1

57--65

EN

A new, sensitive, and selective high-performance liquid chromatography (HPLC) method with fluorimetric detection was developed for the determination of moxifloxacin (MOX) in human breast milk. MOX was precolumn derivatized with fluorescamine; the fluorescent derivative was separated on an RP C18 column using a mobile phase composed of acetonitrile–10 mM orthophosphoric acid by isocratic elution with flow rate of 0.5 mL min -1. The method was based on the measurement of the derivative using fluorescence detection at 481 nm with excitation at 351 nm. The calibration curve was linear over the range of 1–40 μg Ml -1. Limit of detection (LOD) and limit of quantitation (LOQ) were found to be 0.3 and 1 μg Ml -1, respectively. Intra-day and interday repeatabilities were less than 3.15%.

4

Rational therapy of ocular surface bacterial infections with fluoroquinolones

63%

Trojacka E. , Izdebska J.

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nr 2

119-123

PL

Prawidłowa powierzchnia oka ma szereg mechanizmów chroniących ją przed inwazją bakterii chorobotwórczych. W przypadku przełamania fizjologicznej bariery dochodzi do rozwoju zakażenia i stanu zapalnego. Jednymi z częstszych chorób zakaźnych powierzchni oka są bakteryjne zapalenia spojówek i rogówki. Terapia tych schorzeń powinna bazować na racjonalnym stosowaniu antybiotyków o szerokim spektrum działania przeciwbakteryjnego, wysoce skutecznych i bezpiecznych. Wszystkie powyższe cechy maja fluorochinolony: ofloksacyna, lewofloksacyna i moksyfloksacyna.

EN

There are many mechanisms, that protect healthy ocular surface from invasion of pathogenic bacteria. Infection and inflammation develop on the ocular surface in case of damaging natural defensive barrier. One of the most common ocular surface infections are bacterial conjunctivitis and keratitis. Rational therapy of these diseases should be based on antibiotics that have broad antimicrobial spectrum, good efficacy and safety. All these qualities have fluoroquinolones: ofloxacin, levofloxacin and moxifloxacin.

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Novel gyrase mutations and characterization of ciprofloxacin-resistant clinical strains of Enterococcus faecalis isolated in Poland

51%

Piekarska K. , Gierczynski R. , Lawrynowicz-Paciorek M. , Kochman M. , Jagielski M.

Polish Journal of Microbiology

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2008

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tom 57

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nr 2

EN

The activity of ciprofloxacin, sparfloxacin and moxifloxacin was determined for 205 Enterococcus faecalis isolates from patients of five hospitals (Warsaw, Poland; collected from 2000 to 2002). Ciprofloxacin resistant and intermediate isolates were numerous (53.7%). Among them, highly resistant (MIC≥16 mg/l) isolates predominated (98%). Isolates resistant to ciprofloxacin were also resistant to sparfloxacin and moxifloxacin. The parC and gyrA QRDRs (quinolone-resistance-determining region) of 11 isolates with ciprofloxacin MICs from 1 to 256 mg/l were analysed by DNA sequencing. In ParC one kind of amino acid substitution (of Ser-85 to Ile) in 9 E. faecalis strains with MICs from 16 to 256 mg/l was observed. In GyrA Ser-84 was changed to one of four different amino acids: Arg, He, Cys or Tyr, however no association between the amino acid type and MIC value was found. The last two substitutions have not been reported to date for E. faecalis. Moreover, our results may suggest that mutations within parC and gyrA are associated with development of a high-level of ciprofloxacin resistance.

6

First isolation of Clostridium difficile PCR-ribotype 027-toxinotype III in Poland

51%

Pituch H. , Bakker D. , Kuijper E. , Obuch-Woszczatynski P. , Wultanska D. , Nurzynska G. , Bielec A. , Bar-Andziak E. , Luczak M.

Polish Journal of Microbiology

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2008

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tom 57

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nr 3

EN

Of 175 Clostridium difficile strains isolated from patient hospitalized in one academic hospital in Warsaw between 2005-2006 one isolate belonged to PCR-ribotype 027/toxinotype III. This isolate had tcdA, tcdB, binary toxin genes (cdtA and cdtB), a 18-bp deletion and a 1 bp deletion at 117 position in the tcdC gene. Antimicrobial susceptibility tests revealed high level resistance to erythromycin, moxifloxacin and gatifloxacin. This is a first report of the 027 strain of C. difficile in Poland.