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)

There is continued interest in the development of oral beta-lactam compounds, which can be used clinically to treat various bacterial infections, particularly those caused by beta-haemolytic streptococci. Cefixime is a new orally active cephalosporin, with a broad spectrum of antibacterial activity, including Enterobacteriaceae, Haemophilus influenzae, Branhamella catarrhalis, Streptococcus pneumoniae and Streptococcus pyogenes. Cefixime is highly resistant to hydrolysis by most beta-lactamases. In this study the authors examined the effects of this molecule on Group A and Group B beta-haemolytic streptococci, recently isolated from clinical specimens in the authors' laboratory. MICs and the growth curves of 36 strains of Group A streptococci and the effects of sub-MICs on buccal cell adhesion were evaluated. The results show that concerning the sub-MIC cefixime effect on streptococci adherence, the treatment led to a decrease in adherence to the cells of the strains studied. Moreover cefixime showed good activity with 86.1% of the strains with MIC less than or equal to 0.5 microgram/ml, and the growth curves demonstrated that the molecule possesses a bactericidal effect after 3 h. Concerning Group B streptococci, 70.3% of the strains showed a MIC less than or equal to 2 micrograms/ml. In conclusion cefixime demonstrates good activity on beta-haemolytic streptococci, particularly those of Group A.
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PMID:Cefixime shows good effects on group A and group B beta-haemolytic streptococci. 176 18

LY281389 is a new 14-member ring macrolide which is presently being developed for possible clinical use against bacterial infections. We compared the in vitro activity of LY281389 with erythromycin, ampicillin, augmentin and cephalexin against 610 clinical isolates. The new drug inhibited 97 and 11% of methicillin-sensitive and methicillin-resistant Staphylococcus aureus isolates, respectively, 59% of coagulase-negative staphylococci, 63% of enterococci and 74% of Haemophilus influenzae. All the 171 isolates of Streptococcus Lancefield group A, group B and Streptococcus pneumoniae were susceptible to LY281389 at MIC values ranging between 0.03 and 0.24 micrograms/ml. In vitro activity of LY281389 against the bacteria tested was comparable to that of erythromycin.
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PMID:In vitro activity of LY281389 and comparison with erythromycin and oral beta-lactams. 179 Jul 25

The in vitro activity of ME-1206, a new aminothiazolyl cephalosporin that can be orally absorbed when converted to an ester, was compared with that of other beta-lactams. ME-1206 inhibited 50% of the Enterobacteriaceae at 2 micrograms/ml, similar to cefotaxime, ceftazidime, and cefixime. It did not inhibit, MIC greater than or equal to 32 micrograms/ml, Enterobacter species or Citrobacter freundii resistant to cefotaxime and ceftazidime, and it was less active than cefotaxime and ceftazidime against Serratia marcescens. Haemophilus influenzae, Neisseria gonorrhoeae, and Moraxella catarrhalis were inhibited by less than or equal to 0.25 micrograms/ml of ME-1206 inhibited hemolytic streptococci groups A, B, C, and G, MIC90 0.06 micrograms/ml, but it did not inhibit enterococci. Pseudomonas aeruginosa and other pseudomonads were resistant to ME-1206. MICs and MBCs of ME-1206 for susceptible species were within a dilution. ME-1206 was not hydrolyzed by TEM-1 or TEM-2, but was hydrolyzed by TEM-3 and TEM-5. ME-1206 was hydrolyzed by beta-lactamases of Morganella, Proteus vulgaris, and K1 of Klebsiella oxytoca, but minimally by the P99 beta-lactamase of Enterobacter cloacae. ME-1206 is comparable in in vitro activity and beta-lactamase stability to many of the current cephalosporins.
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PMID:In vitro activity of a new cephalosporin ME-1206 compared with other agents. 179 56

Clarithromycin is metabolised in man mainly to the 14-hydroxy derivative, which is also biologically active. As this metabolite is not produced in rodents, we used a murine model of Haemophilus influenzae pulmonary infection to compare the in-vivo activity of clarithromycin and 14-hydroxy clarithromycin, alone and in combination, and erythromycin. In terms of bacterial killing, clarithromycin's 14-hydroxy metabolite was much more active than clarithromycin and erythromycin at doses of 100 mg/kg. For the combination tests, low doses of 14-hydroxy clarithromycin (12, 16 and 24 mg/kg) were ineffective alone but potentiated the bactericidal activity of clarithromycin (100 mg/kg) (P less than 0.01-0.001). The in-vivo results can be explained by in-vitro and pharmacokinetic data: the MIC and MBC of 14-hydroxy clarithromycin are half those of clarithromycin and erythromycin, while the combination of clarithromycin and its metabolite was synergistic in terms of bacteriostatic and bactericidal activities. Potentially useful levels of 14-hydroxy clarithromycin were found after oral administration of low doses, with a prolonged half-life compared with that of the parent compound. On the basis of these results it appears that the 14-hydroxy metabolite may have an important role to play in the treatment of bronchopulmonary infections in man due to H. influenzae.
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PMID:Individual and combined activities of clarithromycin and its 14-hydroxy metabolite in a murine model of Haemophilus influenzae infection. 182

The in-vitro antibacterial activity of clarithromycin, its 14-hydroxy metabolite and a combination containing clarithromycin and the 14-hydroxy metabolite in a ratio of three parts of the former to one part of the latter were compared with erythromycin by determination of MICs. Disc susceptibility testing was also performed using discs containing 6 micrograms clarithromycin, 6 micrograms clarithromycin with 2 micrograms 14-hydroxy-clarithromycin, 3 micrograms clarithromycin and 3 micrograms clarithromycin with 1 microgram 14-hydroxy-clarithromycin. This was to determine a suitable disc content and minimum zone diameter to distinguish between sensitive and resistant strains using a breakpoint of 4 mg/l clarithromycin. Clarithromycin showed similar activity to erythromycin against Streptococcus pneumoniae and Haemophilus influenzae, although the 14-hydroxy metabolite was more active against H. influenzae. The clarithromycin/14-hydroxy metabolite combination was most active against beta-haemolytic streptococci (Groups A-C) (mode MIC 0.06 mg/l). The parent compound and the combination were similarly active against Staphylococcus aureus (MIC50 0.12 mg/l). Branhamella catarrhalis was more susceptible to clarithromycin (MIC90 0.06) than to erythromycin (MIC90 0.25 mg/l). Activities of all compounds against S. epidermidis and enterococci were similar but against Neisseria species erythromycin was the more active compound. The 6 micrograms clarithromycin disc strength was found to give the most consistent results for all isolates. Using a breakpoint of 4 mg/l, minimum zone diameters indicative of sensitivity were as follows: 16 mm for staphylococci, 17 mm for respiratory pathogens and 11 mm for streptococci and Neisseria spp.
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PMID:The in-vitro and disc susceptibility testing of clarithromycin and its 14-hydroxy metabolite. 182 73

GR69153 is a C-7 catechol cephalosporin with a broad spectrum of activity against members of the family Enterobacteriaceae (MICs for 50% of strains tested [MIC50s], 0.008 to 0.5 micrograms/ml), Staphylococcus aureus (MIC50, 4 micrograms/ml), Pseudomonas aeruginosa (MIC50, 0.25 micrograms/ml), Haemophilus influenzae (MIC50, 0.03 micrograms/ml), Neisseria gonorrhoeae (MIC50, 0.03 micrograms/ml), and Acinetobacter spp. (MIC50, 2 micrograms/ml). Potent GR69153 activity was also demonstrated against Moraxella catarrhalis, pneumococci, beta-hemolytic streptococci, gram-positive anaerobes, and most species of coagulase-negative staphylococci. The activity of GR69153 was generally two- to fourfold greater than that of ceftazidime. Resistance level GR69153 MICs for 90% of strains tested (greater than or equal to 32 micrograms/ml) were found most often among Citrobacter freundii, Enterobacter spp. and Morganella morganii strains. GR69153 did not significantly inhibit enterococci, Xanthomonas maltophilia, the Bacteroides fragilis group, Corynebacterium jeikeium, or Listeria monocytogenes. GR69153 was bactericidal and was generally beta-lactamase stable, and MICs were only slightly increased by high inoculum concentrations. Activity was enhanced in an iron-deficient medium, and a modest MIC difference attributed to iron availability was noted between standard agar and broth test results. GR69153 was confirmed to be a potent, catechol-substituted cephalosporin with a spectrum slightly wider than that of ceftazidime, but it was less active than cefpirome or imipenem against some gram-positive pathogens and anaerobes.
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PMID:In vitro evaluation of GR69153, a novel catechol-substituted cephalosporin. 185 74

It has been reported in some studies that the combination of aztreonam (AZT) and clindamycin (CLDM) have high clinical effectiveness in the treatment of intractable infections. We, therefore, studied combined in vitro antibacterial activity of these 2 compounds using many freshly isolated strains. 1. AZT and CLDM in combination had synergistic effects on Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, and Haemophilus influenzae, which are sensitive or quasi-sensitive to CLDM, in the presence of CLDM at MIC or sub-MIC. 2. For Escherichia coli, Klebsiella pneumoniae, Citrobacter freundii, Enterobacter cloacae, Serratia marcescens, and Pseudomonas aeruginosa, which are not sensitive to CLDM, the 2 drugs in combination showed synergistic effects on some species and additive or slightly additive effects on most species in the presence of CLDM at those concentrations which are usually maintained in blood. 3. The 2 drugs showed no antagonism.
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PMID:[Combined antibacterial activity of aztreonam and clindamycin against clinically isolated strains]. 188 Sep 32

Lomefloxacin has marked activity against Gram-negative bacilli including Enterobacteriaceae, non-fermenting strains and Haemophilus influenzae with 98% of all isolates tested having MICs of 0.25 mg/l or less. Sixty-eight per cent of Pseudomonas aeruginosa strains were sensitive to 1 mg/l with a few strains resistant to 8 or 16 mg/l. Gram-positive cocci were more resistant, particularly streptococci, where the MICs vary between 1 and 8 mg/l. Bactericidal activity was similar to inhibitory activity and the effect of increasing serum concentrations and bacterial inocula was minimal. The MIC and MBC were increased in the presence of urine, particularly at an acid pH 5. Comparative MICs showed that lomefloxacin was more active than ofloxacin and pefloxacin, similar to norfloxacin but less active than ciprofloxacin for Gram-negative bacteria but not for Gram-positive cocci. Comparative studies with sensitivity disc concentrations showed that a 5 micrograms disc was more satisfactory than the 10 micrograms disc as the zone sizes were more suitable for routine testing. Solutions of lomefloxacin showed instability in bright sunlight when 52% of activity was lost in 1 h. Similar instability was shown in impregnated discs which lost up to 40% activity in 6 h exposure. Lomefloxacin showed a wide range of activity against Gram-negative bacteria including multiresistant strains and Pseudomonas spp. Gram-positive bacteria were less susceptible, with streptococci more resistant than staphylococci. Lomefloxacin is well absorbed after oral administration giving high blood and urine concentrations and its prolonged half-life means once daily dosing in the treatment of many types of bacterial infection may be possible.
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PMID:Antibacterial activity of lomefloxacin. 188 17

Sparfloxacin (AT-4140 and CI-978) was evaluated for activity against 194 clinical isolates of staphylococci, streptococci, Enterococcus faecalis, anaerobic Gram-positive cocci, and Haemophilus sp. The MIC of sparfloxacin for greater than 93% of the strains tested was less than or equal to 0.5 microgram/ml. Sparfloxacin demonstrated increased activity against enterococci, staphylococci, pneumococci, and anaerobic cocci when compared with ciprofloxacin.
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PMID:In vitro activity of sparfloxacin (AT-4140 and CI-978), a new quinolone antimicrobial agent, against Haemophilus and gram-positive cocci. 188 86

A total of 3,144 clinical isolates from 3,011 consecutive patients were tested against lomefloxacin by the agar dilution method. They consisted of 1,380 isolates of Enterobacteriaceae, 527 pseudomonads, 47 Haemophilus influenzae, 53 Acinetobacter, 42 Brucella melitensis, 903 staphylococci and 192 strains of enterococci. In vitro activity of lomefloxacin was compared with ciprofloxacin, norfloxacin, beta-lactams and aminoglycosides. Over 98% of Enterobacteriaceae were susceptible to lomefloxacin with an MIC of 0.06-4.0 micrograms/ml. It also inhibited 93 and 85% clinical isolates of Pseudomonas aeruginosa and Xanthomonas maltophilia, respectively. All isolates of Haemophilus, Brucella and Staphylococcus aureus were susceptible to this fluoroquinolone. However, only 43% of the 192 strains of enterococci exhibited in vitro susceptibility. Lomefloxacin was found to be comparable to ciprofloxacin and norfloxacin in its in vitro activity, and superior to most penicillins, cephalosporins and aminoglycosides against both gram-negative and gram-positive bacteria except enterococci.
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PMID:In vitro activity of lomefloxacin, a difluorinated quinolone, compared with other antimicrobials. 188 4


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