Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0348321 (Haemophilus)
 15,372 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The in vitro activities of 12 quinolones and four antibiotics were determined against 15 veterinary mycoplasmal species and four species of bacteria commonly involved in respiratory infections in pigs. The newer quinolones were markedly more active in vitro against a wide range of mycoplasmas than nalidixic acid and the earlier quinolones. Against Mycoplasma hyopneumoniae ciprofloxacin was the most active quinolone with a geometric mean minimal inhibitory concentration (MIC) against 16 strains of 0.01 microgram ml-1 compared with 0.04 microgram ml-1 for tiamulin, 0.06 microgram ml-1 for tylosin, 0.17 microgram ml-1 for oxytetracycline and 0.23 microgram ml-1 for gentamicin. M hyosynoviae was less sensitive to the quinolones with mean MICs of 0.6 microgram ml-1 for ofloxacin and 0.7 microgram ml-1 for ciprofloxacin compared with 0.034 microgram ml-1, or less, for tiamulin. Norfloxacin and its 6-chloro analogue were both mycoplasmacidal in vitro at five or 10 times their MICs against M hyopneumoniae UCD4. Tiamulin was mycoplasmastatic. The quinolones were also active against porcine Bordetella bronchiseptica and Pasteurella multocida strains and Haemophilus species. Ciprofloxacin was the most active quinolone with mean MICs of 0.58 microgram ml-1 against B bronchiseptica (nine strains), 0.026 microgram ml-1 against P multocida (five strains) and 0.01 microgram ml-1, or less, against Haemophilus pleuropneumoniae (nine strains) and H parasuis (two strains) compared with mean MICs of from 0.5 microgram ml-1 to 64 micrograms ml-1, or more, for the antibiotics. This combination of excellent mycoplasmacidal activity against M hyopneumoniae and good antibacterial activity, suggests that the quinolones have great potential for treating respiratory infections in pigs, including enzootic pneumonia.
 ...
PMID:In vitro evaluation of various quinolone antibacterial agents against veterinary mycoplasmas and porcine respiratory bacterial pathogens. 270 85

Ciprofloxacin is a new fluorinated 4-quinolone with a broad spectrum of antimicrobial activity which includes both Gram-negative and Gram-positive bacteria. In this study the in vitro activity of ciprofloxacin has been determined against bacteria associated with respiratory tract infections and compared with that of other antimicrobial agents used in the therapy of such infections. Ciprofloxacin (MIC90 0.008 mg/l) was highly active against Haemophilus influenzae, including isolates producing beta-lactamase which were resistant to amoxycillin. Ciprofloxacin (MIC90 0.06 mg/l) was also highly active against Branhamella catarrhalis, again including those isolates resistant to amoxycillin as a result of beta-lactamase production. Isolates of Streptococcus pneumoniae were less susceptible to ciprofloxacin (MIC90 2 mg/l) but were highly susceptible to amoxycillin (MIC90 less than 0.12 mg/l) and erythromycin (MIC90 0.25 mg/l). Isolates of Klebsiella aerogenes were highly susceptible to ciprofloxacin (MIC90 0.06 mg/l) but much less so to amoxycillin, sulfamethoxazole, trimethoprim, oxytetracycline and erythromycin. Ciprofloxacin (MIC90 0.5 mg/l) was very active against Staphylococcus aureus, including those isolates resistant to amoxycillin and flucloxacillin, and against Mycoplasma pneumoniae. Together with rifampicin and erythromycin, ciprofloxacin was highly active against Legionella pneumophila (MIC90 0.015 mg/l). These results suggest that clinical evaluation of ciprofloxacin in the treatment of respiratory tract infections is justified.
 ...
PMID:Comparative in vitro activity of ciprofloxacin and other unrelated antimicrobials against bacterial respiratory tract pathogens. 273 80

Oral quinolones such as ciprofloxacin are promising agents in the treatment of serious bronchopulmonary infections due to susceptible gram-negative micro-organisms such as Haemophilus influenzae, Branhamella catarrhalis, Klebsiella pneumoniae and even Pseudomonas aeruginosa. Their moderative activity against Streptococcus pneumoniae may limit the use of these agents in the treatment of acute exacerbations of chronic bronchitis and in the empiric management of community-acquired bacterial pneumonia. Further prospectively designed studies are needed to address this issue. The ability of quinolones to effectively penetrate bronchial mucosa and to be concentrated within macrophages may afford additional advantage to these agents. They should not be used as a sole agent in the treatment of aspiration pneumonia nor anaerobic pleuropulmonary disease. Quinolones are very active in experimental models of Legionnaire's disease and deserve further clinical study. Ciprofloxacin is a promising alternative to standard parenteral drugs in the management of Pseudomonas aeruginosa infections in adults with cystic fibrosis. The potential for drug interactions with theophylline must be kept in mind for patients on both of these drugs.
 ...
PMID:Role of fluoroquinolones in lower respiratory tract infections. 292 Apr 82

We tested ciprofloxacin, a new quinoline derivative, against 783 gram-positive and gram-negative bacteria utilizing either standardized microbroth or agar dilution methods. Ciprofloxacin activity was compared to that of cephalosporins, enoxacin, norfloxacin, ampicillin, chloramphenicol, tobramycin, ticarcillin, erythromycin and trimethoprim/sulfamethoxazole. MIC90 values (range) in micrograms/ml were: Pseudomonas aeruginosa = 1 (less than or equal to 0.015-8); Staphylococcus spp. = 0.12 (less than or equal to 0.015-1); Enterobacteriaceae = 0.03 (less than or equal to 0.015-1); Haemophilus influenzae = 0.015 (less than or equal to 0.004-0.03); Streptococcus faecalis = 2 (0.5-4). The MIC90 of ciprofloxacin for 98 tobramycin-resistant isolates was 2.0 micrograms/ml. Ciprofloxacin was stable at temperatures of 35, 22, 4, -20 and -70 degrees C for up to 15 weeks. Varying the inoculum from 10(3) to 10(7) colony forming units per ml or the pH from 6-9 resulted in no increase in the MIC. Of the new quinoline derivatives tested, ciprofloxacin demonstrated consistently superior antibacterial activity. Ciprofloxacin may be particularly effective for oral administration in infections requiring prolonged antibiotic therapy, such as bone, joint, and complicated soft tissue infections, and in pulmonary infections in patients with cystic fibrosis.
 ...
PMID:In vitro activity of ciprofloxacin against pediatric pathogens. 293 33

Nalidixic and five newer 4-quinolones, ciprofloxacin, enoxacin, norfloxacin, ofloxacin and pefloxacin were tested against 576 recent clinical aerobic bacterial isolates. The 4-quinolones were regularly active (MIC90 less than 4 mg/l) against the following bacteria: Staphylococcus aureus, S. epidermidis, S. saprophyticus, different Enterobacteriaceae, Haemophilus influenzae, Campylobacter jejuni, Pseudomonas aeruginosa, Agrobacter spp., Aeromonas spp., Plesiomonas spp., Neisseria meningitidis. Other bacteria were usually intermediately susceptible or resistant: different streptococci, Listeria monocytogenes, Nocardia asteroides, P. maltophilia, Achromobacter xylosoxydans and Alcaligenes denitrificans. Ciprofloxacin was the most potent compound, followed by ofloxacin and pefloxacin, norfloxacin and enoxacin being less active. All the 4-quinolones were much more active than nalidixic acid. The MBC/MIC ratios of the 4-quinolones were between 1 and 2 with a majority of strains, and between 2 and 3 with Streptococcus agalactiae, Str. faecalis and L. monocytogenes. A two- to eight-fold increase of MIC was observed by increasing the inoculum 10,000-fold with most of the strains tested. Susceptible bacterial population of Klebsiella pneumoniae, Enterobacter cloacae, Serratia marcescens and P. aeruginosa contained more clones resistant to nalidixic acid (10(4) to 10(8) at four times the MIC) than to 4-quinolones (10(5) to 10(9) at four times the MIC). Supplementing the media with MgSO4 produced smaller inhibition zone diameters with a disc diffusion method than those obtained with non-supplemented agar, with all quinolone or strains. Less regular effect, or no effect was obtained after supplementation with ZnSO4 or Ca(NO3)2.
 ...
PMID:In-vitro activity of newer quinolones against aerobic bacteria. 294 Feb 14

The minimal inhibitory concentrations (MICs) of twelve 4-quinolone antimicrobials were determined for 100 isolates of Haemophilus influenzae (including 30 beta-lactamase producing strains) and 100 isolates of Streptococcus pneumoniae. MICs were determined using an agar dilution technique in Mueller-Hinton agar supplemented with 10% lysed horse blood. The inoculum used was approximately 10(4) colony-forming units, contained in 10 microliters of Mueller-Hinton broth, which was applied to the agar plates using a multipoint inoculator. Following inoculation, plates were incubated at 37 degrees C for 18 h in an atmosphere enriched to 10% carbon dioxide. The MIC of each antimicrobial for each isolate examined was determined as the lowest concentration of the antimicrobial which completely inhibited growth of the inoculum. The minimum concentrations required to inhibit the growth of 50% (MIC50) and 90% (MIC90) of the organisms examined were also determined. The more recently synthesised 4-quinolones showed considerably greater activity than nalidixic acid and pipemidic acid against clinical isolates of Haemophilus influenzae and Streptococcus pneumoniae. There was no apparent difference between the MICs observed for beta-lactamase producing and non-beta-lactamase producing strains of Haemophilus influenzae. Ciprofloxacin was the most active 4-quinolone examined (MIC90 for Haemophilus influenzae 0.008 microgram/ml; Streptococcus pneumoniae 2 micrograms/ml). Clinical studies on a possible role for some of the more recently synthesised 4-quinolones in the management of patients with respiratory infection are indicated.
 ...
PMID:The comparative activity of twelve 4-quinolone antimicrobials against Haemophilus influenzae and Streptococcus pneumoniae. 294 Dec 58

Ciprofloxacin pharmacokinetics were studied in 6 volunteers after 250 and 500 mg single oral doses. Mean peak serum levels were 1.45 micrograms/ml and 2.5 micrograms/ml for 250 and 500 mg doses. The 12-h levels were 0.12 micrograms and 0.22 micrograms. T1/2 alpha values were 0.32 and 0.43 h; T1/2 beta was 4 h and Vd (area) values were 80L and 90L for the two doses respectively. AUC was 5.65 h. micrograms/ml and 10.37 h. micrograms/ml. Serum clearance was 23L for both doses. Approximately 49% of the 250 mg dose and 43% of the 500 mg dose was recovered in the urine. Ciprofloxacin's in vitro activity and human pharmacology should permit a twice or once-daily dosing schedule for systemic infections due to most Enterobacteriaceae, Haemophilus, Branhamella and Pseudomonas and S. aureus, and once-daily doses for urinary and gastrointestinal infections.
 ...
PMID:The pharmacology of orally administered ciprofloxacin. 294 Dec 62

The in vitro activity of fleroxacin (Ro 23-6240) against 441 bacterial isolates was compared with those of ciprofloxacin, ofloxacin, amoxycillin, cefadroxil, cefuroxime and tobramycin. An agar dilution method was used for the determination of minimal inhibitory concentrations (MICs). Ciprofloxacin showed the highest activity against the Enterobacteriaceae, 95% of the isolates were inhibited by 0.06 mg/l, but fleroxacin and ofloxacin were also highly active (MIC 90% = 0.5 and 0.25 mg/l, respectively). Ciprofloxacin was the most active agent against Pseudomonas aeruginosa (MIC 90% = 0.12 mg/l), whereas the activities of fleroxacin and ofloxacin were more variable. Tobramycin was highly active against P. aeruginosa, 75% of the isolates were inhibited by 0.5 mg/l or less. The quinolones and tobramycin exhibited high activity against Acinetobacter calcoaceticus, the great majority of the isolates being susceptible to 0.5 mg/l or less of any agent. All the quinolones showed high activity against Staphylococcus aureus, but fleroxacin was less active against Staphylococcus epidermidis and Staphylococcus saprophyticus than were the other derivatives. The pneumococcal and streptococcal isolates were markedly less susceptible to fleroxacin than to the other quinolones tested (MIC range 4-32 mg/l). All isolates of Haemophilus influenzae and Neisseria gonorrhoeae were inhibited by the lowest concentration of the quinolones employed in the study (0.03 mg/l). Cefuroxime was also highly active against N. gonorrhoeae, whether the strains were beta-lactamase-producing or not, but was somewhat less active against H. influenzae. The quinolones displayed moderate and similar activity against Bacteroides fragilis isolates (MIC range 1-16 mg/l). The MICs of fleroxacin against gram-negative rods were generally 4-16 times higher at pH 8.8 than those obtained at pH 5.8 and 7.3. The activity against gram-positive cocci was not markedly influenced by changes in pH.
 ...
PMID:In vitro studies of fleroxacin (Ro 23-6240), a new trifluorinated quinolone derivative. 314 Nov 16

Ciprofloxacin is an investigational quinolone agent possessing an impressive antibacterial spectrum. Its pharmacokinetics were studied in six volunteers after 250-mg and 500-mg single oral doses, and its bactericidal activity compared to that of trimethoprim-sulfamethoxazole given to the same volunteers. Mean peak serum levels were 1.45 micrograms/mL and 2.46 micrograms/mL for 250-mg and 500-mg doses, and time to peak was 1 and 1.3 hours. The 12-hour levels were 0.12 micrograms and 0.22 microgram. Half-life (T1/2)alpha were 0.32 and 0.43 with T1/2 beta were 3.97 and 4.15 and volume of distribution (area) were 80L and 90L, respectively. Area under the concentration curve (AUC) was 5.65 h X micrograms/mL and 10.37h X micrograms/mL. Serum clearance was 23L for both doses. Approximately 49% of the 250-mg dose and 43% of the 500-mg dose was recovered in the urine. Bactericidal levels were determined against clinical isolates. Sera at 1.5 hours after the 500-mg dose averaged bactericidal levels of 1:20 or better for an Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and beta-lactamase producing Haemophilus influenzae and Branhamella catarrhalis. Urinary bactericidal levels at eight to 12 hours were greater than or equal to 1:157 for E coli, K pneumoniae, gentamicin-piperacillin resistant P aeruginosa, Staphylococcus aureus, and 1:20 for Streptococcus faecalis. Serum bactericidal levels were superior, and urine bactericidal levels were superior or equal to the bactericidal levels obtained with trimethoprim-sulfamethoxazole.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:The pharmacokinetics and serum and urine bactericidal activity of ciprofloxacin. 315 5

We studied the comparative in vitro activities of 10 oral antimicrobial agents against 147 aerobic and 61 anaerobic bacteria making up species in 13 genera (Staphylococcus aureus, streptococci, Eikenella corrodens, Pasteurella multocida, Haemophilus-Actinobacillus spp., M-5, EF-4, Moraxella spp., Flavobacterium IIb, Bacteroides melaninogenicus, Bacteroides spp., Fusobacterium spp., and Peptostreptococcus spp.) that were isolated from bite wounds. Cefuroxime was generally greater than fourfold more active than cephalexin and cefadroxil against all aerobic isolates, including Pasteurella multocida. The fluoroquinolones were highly active against most aerobic isolates but were less active against anaerobic isolates. Ciprofloxacin was generally more active than either enoxacin or ofloxacin. Discrepancies of greater than 30% in the interpretation of susceptibilities between break points suggested by the National Committee for Clinical Laboratory Standards and those related to oral dose peak levels (one-half to one-quarter of maximum achievable concentrations) were noted in 14% (18 of 130) of the instances.
 ...
PMID:Comparative activities of cefuroxime, amoxicillin-clavulanic acid, ciprofloxacin, enoxacin, and ofloxacin against aerobic and anaerobic bacteria isolated from bite wounds. 319 Feb 2


<< Previous 1 2 3 4 5 6 7 8 Next >>