Emergence of fluoroquinolone resistance among multiply resistant strains of Streptococcus pneumoniae in Hong Kong.
(25/2482)
The MICs of 17 antimicrobial agents for 181 Streptococcus pneumoniae strains were determined by the E-test. Overall, 69.1% were penicillin resistant (MIC > 0.06 microgram/ml). Resistance to ciprofloxacin (MIC > 2 microgram/ml), levofloxacin (MIC > 2 microgram/ml), or trovafloxacin (MIC > 1 microgram/ml) was found in 12.1, 5.5, or 2.2% of the strains, respectively. These high rates of resistance raise concerns for the future. (+info)
Short-course therapy of acute cystitis: a brief review of therapeutic strategies.
(26/2482)
Acute cystitis is one of the commonest medical problems encountered by primary care physicians. It affects more women than men (8:1), but the incidence among men is increasing. Uncomplicated cystitis by definition occurs in healthy patients with a normal urinary tract, whereas complicated cystitis implies a predisposing or underlying condition. A narrow range of aetiological agents is responsible for most uncomplicated cystitis in women (Escherichia coli in 80% of cases). Recently, however, pathogens usually associated with sexually transmitted disease have been implicated. In women with typical symptoms of acute uncomplicated cystitis, an abbreviated laboratory work-up followed by empirical therapy is recommended. Single-dose and 3 day regimens of co-trimoxazole and the quinolones are as effective as longer regimens and have a higher eradication rate than other commonly used antimicrobials. Relapse rates are slightly higher with single-dose therapy. With this success rate plus the reduced cost and improved patient compliance, these regimens have replaced traditional 5 to 14 day courses of treatment. With increasing resistance of the common urinary pathogens to amoxycillin and, now, co-trimoxazole, the quinolones are a logical choice for empirical therapy of uncomplicated urinary tract infections. (+info)
Activity of gatifloxacin against Haemophilus influenzae and Moraxella catarrhalis, including susceptibility test development, E-test comparisons, and quality control guidelines for H. influenzae.
(27/2482)
In vitro antimicrobial activity and susceptibility testing interpretation criteria and quality control were studied for gatifloxacin, a new 8-methoxy fluoroquinolone, tested against Haemophilus influenzae. Moraxella catarrhalis (600 strains) and H. influenzae (1,400 strains) from the SENTRY Antimicrobial Surveillance Program in North America (Canada and the United States) were also tested against gatifloxacin and 12 other antimicrobial agents. Gatifloxacin (MIC at which 90% of the isolates are inhibited [MIC90], /=18 mm) was also suggested for H. influenzae testing. No interpretive errors were observed. Quality control guidelines for H. influenzae ATCC 49247 were determined by using the NCCLS M23-T3 (1998) study design. The results from the nine-laboratory protocol suggested the following control ranges: for broth microdilution tests, 0.004 to 0.03 microg/ml; for disk diffusion testing, 33 to 41 mm. Gatifloxacin appears to be a potent anti-Haemophilus fluoroquinolone compound with in vitro testing interpretive criteria that will produce accurate results (disk diffusion, broth microdilution, and E-test). (+info)
Primary active transport of organic anions on bile canalicular membrane in humans.
(28/2482)
Biliary excretion of several anionic compounds was examined by assessing their ATP-dependent uptake in bile canalicular membrane vesicles (CMV) prepared from six human liver samples. 2, 4-Dinitrophenyl-S-glutathione (DNP-SG), leukotriene C4 (LTC4), sulfobromophthalein glutathione (BSP-SG), E3040 glucuronide (E-glu), beta-estradiol 17-(beta-D-glucuronide) (E2-17G), grepafloxacin glucuronide (GPFXG), pravastatin, BQ-123, and methotrexate, which are known to be substrates for the rat canalicular multispecific organic anion transporter, and taurocholic acid (TCA), a substrate for the bile acid transporter, were used as substrates. ATP-dependent and saturable uptake of TCA, DNP-SG, LTC4, E-glu, E2-17G, and GPFXG was observed in all human CMV preparations examined, suggesting that these compounds are excreted in the bile via a primary active transport system in humans. Primary active transport of the other substrates was also seen in some of CMV preparations but was negligible in the others. The ATP-dependent uptake of all the compounds exhibited a large inter-CMV variation, and there was a significant correlation between the uptake of glutathione conjugates (DNP-SG, LTC4, and BSP-SG) and glucuronides (E-glu, E2-17G, and GPFXG). However, there was no significant correlation between TCA and the other organic anions, implying that the transporters for TCA and for organic anions are different also in humans. When the average value for the ATP-dependent uptake by each preparation of human CMVs was compared with that of rat CMVs, the uptake of glutathione conjugates and nonconjugated anions (pravastatin, BQ-123, and methotrexate) in humans was approximately 3- to 76-fold lower than that in rats, whereas the uptake of glucuronides was similar in the two species. Thus there is a species difference in the primary active transport of organic anions across the bile canalicular membrane that is less marked for glucuronides. (+info)
Activity of gatifloxacin compared to those of five other quinolones versus aerobic and anaerobic isolates from skin and soft tissue samples of human and animal bite wound infections.
(29/2482)
The activity of gatifloxacin against 308 aerobes and 112 anaerobes isolated from bite wound infections was studied. Gatifloxacin was active at +info)
Effect of HSR-903, a new fluoroquinolone, on the concentration of theophylline in serum.
(30/2482)
The effect of HSR-903, a new fluoroquinolone, on the concentration of theophylline in serum in healthy male volunteers was investigated. The concentration of theophylline in serum and the urinary excretion rates of theophylline on day 5 of concomitant dosing with HSR-903 tended to increase compared to those on day 4, when theophylline was given alone; however, the urinary excretion rates of 1-methyluric acid and 3-methylxanthine on day 5 of concomitant dosing with HSR-903 tended to decrease in comparison to those on day 4, when theophylline was given alone. (+info)
Pharmacokinetics and inflammatory-fluid penetration of moxifloxacin following oral or intravenous administration.
(31/2482)
A single 400-mg oral or intravenous (i.v.) dose of moxifloxacin was given to each of eight healthy male volunteers, and 6 weeks later the dose was administered by the other route. The concentrations of the drug in plasma, cantharidin-induced inflammatory fluid, and urine were measured over the subsequent 24 h. The mean maximum concentrations observed in plasma were 4.98 microg/ml after oral dosing and 5.09 microg/ml after i.v. dosing. The mean maximum concentrations attained in the inflammatory fluid were 2.62 and 3.23 microg/ml, respectively. The mean elimination half-lives from plasma were 8.32 and 8.17 h, respectively. The overall penetration into the inflammatory fluid was 103.4 and 104.2%. Over 24 h 15% of the drug was recovered in the urine when administered by either route. (+info)
Pharmacokinetic-pharmacodynamic contributions to the convulsant activity of fluoroquinolones in rats.
(32/2482)
The in vivo convulsant activities in rats of five representative fluoroquinolones (FQs), norfloxacin, enoxacin, sparfloxacin, fleroxacin, and pefloxacin, were compared. The experimental approach allowed distinction between the drugs' ability to reach the pharmacological receptors at the level of the central nervous system (pharmacokinetic contribution) and their ability to interact with these receptors (pharmacodynamic contribution). The presence of a methyl group on the piperazine moiety decreased the pharmacodynamic contribution to the convulsant activity by severalfold, and the ratios of concentrations of the FQs in cerebrospinal fluid (CSF) to concentrations of unbound FQs in plasma varied from about 5 to 75% as a function of lipophilicity. Interestingly, FQs with the highest intrinsic convulsant activities had the lowest levels of diffusion in CSF and vice versa. This in vivo approach provides information complementary to that of in vitro experiments and should be recommended for early preclinical assessment of a new FQ's epileptogenic risk. (+info)