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

The cerebrospinal fluid (CSF) penetration of ofloxacin given orally or or intravenously was studied in cancer patients without meningitis. Each patient was assigned to a different sampling time to assess the relation between time and penetration. Ofloxacin was measured in serum and CSF by high-pressure liquid chromatography and bioassay. In addition, the bactericidal titers were measured in CSF and serum against a set of relevant bacteria. Concentrations measured by high-pressure liquid chromatography and bioassay were well correlated. Peak concentrations in CSF (0.4 to 1 microgram/ml) were observed 2 to 4 h after infusion or oral administration. Peak concentrations in serum were observed just after infusion (2 to 3.5 micrograms/ml) or 1 to 2 h after oral administration (1.7 to 4 micrograms/ml). Measured bactericidal titers were well correlated with the titers expected from the MBC and concentration. High CSF bactericidal titers were observed against Neisseria meningitidis, Haemophilus influenzae, and Escherichia coli, whereas low or no bactericidal titers were obtained against Staphylococcus aureus, Listeria monocytogenes, and Streptococcus pneumoniae.
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PMID:Concentrations of ofloxacin in serum and cerebrospinal fluid of patients without meningitis receiving the drug intravenously and orally. 258 41

SM-7338, a new carbapenem antibiotic, was demonstrated to have potent antibacterial activity against a broad spectrum of aerobes, including Staphylococcus aureus, beta-hemolytic streptococci, Streptococcus pneumoniae, Haemophilus influenzae, Neisseria spp., members of the family Enterobacteriaceae, Pseudomonas spp., and gram-positive and gram-negative anaerobes in a collection of 1,102 unselected clinical isolates. At a concentration of 0.5 micrograms/ml, SM-7338 inhibited 90% of these strains. The spectrum of activity of ceftazidime and cefotaxime was more limited, and many of the Enterobacteriaceae and Pseudomonas spp. were resistant to these agents, piperacillin, or gentamicin. A collection of ofloxacin-resistant strains was inhibited by SM-7338 or imipenem at 4 micrograms/ml. SM-7338 was more active than metronidazole and clindamycin against anaerobes. Of the carbapenems, imipenem had greater activity against staphylococci but SM-7338 was much more active against Haemophilus, Branhamella, and Neisseria spp. and all genera of Enterobacteriaceae tested. The MIC of SM-7338 for 90% of these strains ranged from less than or equal to 0.008 to 0.13 micrograms/ml. When tested against 124 strains of Pseudomonas aeruginosa, SM-7338 inhibited 76% at 0.5 microgram/ml but imipenem inhibited only 15% at this concentration. Both carbapenems exhibited similar activities against Bacteroides spp., but SM-7338 was more active than imipenem against Clostridium spp. The MBC of SM-7338 was most commonly the same as or twice the MIC. SM-7338 and imipenem showed excellent activities against bacteria elaborating chromosome- or plasmid-mediated beta-lactamases, including those conferring resistance to broad-spectrum cephalosporins. The activity of SM-7338 was generally unaffected by the culture medium used, pH, 25% human serum, and inoculum size, but the susceptibility of Xanthomonas maltophilia was medium dependent.
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PMID:In vitro antibacterial activity of SM-7338, a carbapenem antibiotic with stability to dehydropeptidase I. 265 30

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.
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PMID:In-vitro activity of newer quinolones against aerobic bacteria. 294 Feb 14

The inhibitory (MIC) and bactericidal (MBC) activities of a new macrolide A-56268 (TE-031) against 306 clinical aerobic bacterial isolates was compared with that of erythromycin. The MIC90/MBC90 ratios for A-56268 were: Campylobacter jejuni 4/16, Haemophilus influenzae 8/8-16, H. parainfluenzae 8/8-16, Legionella pneumophila 0.06/0.5, methicillin-sensitive isolates of Staphylococcus aureus 0.5/1, and coagulase negative staphylococci 1/8, methicillin resistant isolates of Staph. aureus and coagulase negative staphylococci greater than 16/ greater than 16, Streptococcus pneumoniae 0.06/0.125, streptococcus Group A 0.06/2-4, streptococcus Group B 0.06/8- greater than 16, streptococcus Groups C and G 0.125/8 and Str. faecalis 4/64. Compared with erythromycin, A-56268 had greater inhibitory and bactericidal activity against isolates of L. pneumophila, with an MIC90 16-fold less and an MBC90 eight-fold less than that of erythromycin. Except for enterococci, A-56268 showed inhibitory activity equal to or greater than that of penicillin G against isolates of streptococci and an MIC two-fold less than that of erythromycin. For other strains tested, the inhibitory and bactericidal activities of A-56268 and erythromycin were similar. The clinical importance of the differences between these two macrolides will depend on the pharmacokinetic and tissue penetration properties of the new compound.
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PMID:Comparative in-vitro activities of A-56268 (TE-031) and erythromycin against 306 clinical isolates. 296 68

FCE 22101 is a penem antibiotic which inhibits the majority of Enterobacteriaceae, Haemophilus influenzae, and Neisseria gonorrhoeae at concentrations of 0.5-4 mg/l. It inhibits staphylococci, haemolytic streptococci and Streptococcus pneumoniae at less than or equal to 0.25 mg/l. Pseudomonas aeruginosa and other Pseudomonas species are resistant. Bacteroides fragilis and Clostridium species are inhibited by less than or equal to 1 mg/l. FCE 22101 is not hydrolyzed by the common plasmid and chrosmosomal beta-lactamases. It shows minimal discrepancy between MIC and MBC values and there is minimal effect of inoculum size. Although FCE 22101 is generally less active against Enterobacteriaceae than are cefotaxime and ceftazidime, it does inhibit some Enterobacter spp. resistant to these agents. FCE 22101 and imipenem are similar in activity against Gram-positive and anaerobic species.
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PMID:The in-vitro activity of a novel penem FCE 22101 compared to other beta-lactam antibiotics. 299

The in vitro activities of the new quinolone derivatives ofloxacin, ciprofloxacin, norfloxacin, and pefloxacin against strains of Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis were compared to that of nalidixic acid. Determination of minimal inhibitory concentrations (MICs) was done by agar dilution tests. The new drugs were more active than nalidixic acid. N. meningitidis and H. influenzae (regardless of beta-lactamase production) were highly susceptible. All H. influenzae strains were inhibited by less than or equal to 0.12 mg/l; mode MICs were 0.03 mg/l for norfloxacin and pefloxacin, and 0.50 mg/l for nalidixic acid. All N. meningitidis strains were inhibited by 0.06 mg/l and mode MICs of the new drugs were less than or equal to 0.03 mg/l. Mode MICs for S. pneumoniae were 4 mg/l for norfloxacin and pefloxacin (range 1-16 and 2-8 mg/l respectively) and 1 mg/l for ofloxacin (range 1-4 mg/l). Ofloxacin exhibited a bactericidal activity on H. influenzae (range MBC 0.06-0.50 mg/l; mode MBC: 0.06 mg/l).
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PMID:[Effect ofloxacin on Haemophilus influenza, Streptococcus pneumoniae and Neisseria meningitidis. Comparison with similar molecules]. 316 40

The bactericidal effect of ceftriaxone and cefotaxime was studied by killing curves on 18 Haemophilus influenzae at 2, 4, 6 and 24 h. The MIC of ceftriaxone are between 0.0012 and 0.015 mg/l. The MIC of cefotaxime are between 0.006 and 0.03 mg/l. The MBC of ceftriaxone are between 0.0012 and 0.03 mg/l. The MBC of cefotaxime are between 0.006 and 0.03 mg/l. The bactericidal effect was studied at the concentration of 0.06 mg/l; at this concentration we obtained a reduction of 4 log 10 for 3 strains in 6 hours by both drugs. In 24 h, 16 stains give a 99.99% of killing for ceftriaxone and 18 strains for cefotaxime. Our results do not show a significant difference in the bactericidal effect of the two drugs on Haemophilus.
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PMID:[Bactericidal speed of ceftriaxone and cefotaxime on 18 strains of Haemophilus influenzae]. 330 54

The antibacterial activity of LY164846, a new orally administered semisynthetic cephalosporin, was compared with that of amoxicillin-clavulanic acid against 492 potentially pathogenic respiratory tract and dermal isolates. Against groups A, B, and G streptococci; pneumococci; staphylococci (other than methicillin resistant); Haemophilus influenzae; Branhamella catarrhalis; and meningococci, the MICs for 90% of strains tested of LY164846 and amoxicillin-clavulanic acid were less than or equal to 4 and less than or equal to 1 microgram/ml, respectively. LY164846 was equally active against beta-lactamase-positive and -negative strains of Haemophilus and Staphylococcus. MBC to MIC ratios of LY164846 versus H. influenzae were less than or equal to 2, while those with Staphylococcus aureus were more difficult to determine because of skipped tubes or paradoxic effects. There were minimal inoculum, pH, or serum effects on LY164846 activity against H. influenzae and S. aureus. In time-kill studies, LY164846 and amoxicillin-clavulanic acid at double MICs were 99.9 to 100% bactericidal to H. influenzae in 24 h; two times the MIC of LY164846 and four times the MIC of cephalexin were 99.9 to 100% bactericidal to S. aureus in 24 h. Based on error-rate-bounded analysis, the following interpretative guidelines for 30-micrograms LY164846 disk diffusion test diameters are suggested: greater than or equal to 19 mm, susceptible (MIC, less than or equal to 4 micrograms/ml); 16 to 18 mm, intermediate (MIC, greater than 4 but less than or equal to 8 micrograms/ml); less than or equal to 15 mm, resistant (MIC, greater than 8 micrograms/ml).
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PMID:In vitro activity of an orally administered cephalosporin, LY164846, against potentially pathogenic respiratory and dermal bacterial isolates. 348 28

Second generation cephalosporins are frequently used for the treatment of bacteremic Hemophilus influenzae type b infections. "Breakthrough" meningitis during cefamandole therapy has documented the need for adequate cerebrospinal fluid penetration by these antibiotics if they are to be used in the therapy of Hemophilus infections. A child with H. influenzae type b preseptal cellulitis is reported who initially responded to treatment with intravenous cefuroxime and oral cefaclor. However, while still receiving cefaclor, the child was readmitted with H. influenzae meningitis. Microtiter broth dilution susceptibility testing performed during the second admission showed the isolate to be relatively resistant to cefuroxime (minimum bactericidal concentration [MBC] = 4 micrograms/ml) and resistant to cefaclor (MBC greater than 16 micrograms/ml). This experience documents the need to monitor the clinical response closely during therapy of H. influenzae bacteremic infections with these second generation cephalosporin treatment regimens. In addition, attention should be paid to minimum inhibitory concentrations of these cephalosporins, since variations in H. influenzae type b susceptibility to these agents may limit their efficacy.
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PMID:Onset of Hemophilus influenzae type-b meningitis during cefaclor therapy for preseptal cellulitis. 349 4

The responses of 20 ampicillin-susceptible Haemophilus influenzae type b clinical isolates to the bactericidal action of ampicillin were studied by using a modified agar dilution plate count method. A well-defined paradoxical effect was observed in each of the 24-h killing curve patterns for 19 of the 20 isolates, the remaining isolate showing a less-well-defined but suggestive paradoxical effect after 48 h of ampicillin exposure. For each isolate, the lowest 24-h persister percentage representing maximum killing (paradoxical trough percentage) occurred over a narrow range of concentrations immediately above the MIC, with such paradoxical trough percentages for the 20 isolates ranging from greater than 0.1 to less than 0.001%. Three isolates selected to represent slow, intermediate, and rapid responses were investigated by repetition of 24-h studies and by determination of expanded killing curve patterns. Resultant agar dilution plate count killing curve patterns were found to be reproducible and strain dependent and served to characterize each isolate. The paradoxical effect became more distinct with the prolongation of ampicillin action. Maximum killing was again evident for a narrow range of ampicillin concentrations immediately above the MIC, with persister percentages rising rapidly over the next few ampicillin concentrations to peak at 1 to 2 log10 increments higher than trough percentages. Based on the broad range of responses observed for the 20 isolates, the consistent presence of the paradoxical effect, and the time-dependent nature of bactericidal action, we suggest that the MBC and MBC/MIC ratios are inadequate indices of bactericidal action and that the all-or-none concept of "antimicrobial tolerance" should be abandoned.
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PMID:Ampicillin killing curve patterns of Haemophilus influenzae type b isolates by agar dilution plate count method. 350


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