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)

Agar plates containing antiserum against group B meningococcus or Haemophilus influenzae type b were used to determine the prevalence of cross-reacting K1 and K100 capsular polysaccharide antigens in 265 isolates of disease-causing Escherichia coli. K1 antigen was found in 22% of isolates from various sites. K100 antigen was found in only three isolates. This technique is a convenient method to detect specific E. coli K antigens for evaluation as possible factors important in the virulence of the organism.
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PMID:Screening for cross-reacting capsular polysaccharide K antigens of Escherichia coli using antiserum agar. 40 19

The antibacterial activity of a new 7-dimethylpyridinyl quinolone, WIN 57273, was assessed by using in vitro and in vivo models. Agar inclusion and broth dilution in vitro tests revealed broad-spectrum activity against gram-positive and selected gram-negative organisms, with the greatest potency observed against the staphylococci. The MIC for 90% of coagulase-positive strains tested (MIC90) was less than or equal to 0.002 micrograms/ml; for the coagulase-negative strains the MIC90 was 0.008 micrograms/ml. Against enterococci the MIC90 was 0.06 micrograms/ml, with comparable activity observed against group A and group B streptococci as well as against the pneumococci. In general, the MIC90s for the gram-negative bacteria were less than or equal to 1 micrograms/ml. Exceptions were Serratia marcescens (MIC90, 16 micrograms/ml), Citrobacter freundii (MIC90, 4 micrograms/ml), and Pseudomonas aeruginosa (MIC90, 8 micrograms/ml). The greatest potency was observed against Haemophilus spp. and Neisseria spp., with MIC90s of 0.06 and 0.016 micrograms/ml, respectively. Broad-spectrum activity was also observed against anaerobes, with MIC90s ranging from 0.125 to 0.5 micrograms/ml among the species tested. The in vivo efficacy was determined by using a murine model by calculating the 50% protective doses against a lethal bacterial infection caused by strains of Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pneumoniae, Streptococcus pyogenes, Listeria monocytogenes, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. The staphylocci were most susceptible, with 50% protective doses for all strains ranging from 0.1 to 0.7 mg/kg. With the exception of the Pseudomonas infection, which was refractory to treatment, animals that were part of the other infection models responded to less than 10 mg/kg. Equivalent activity was seen with the subcutaneous or the oral route of drug administration. WIN 57273 was significantly more potent than ciprofloxacin in treating gram-positive bacterial infections (2- to 20-fold) but was significantly less effective at treating gram-negative bacterial infections (30- to 300-fold).
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PMID:In vitro and in vivo activities of a new quinolone, WIN 57273, possessing potent activity against gram-positive bacteria. 234 63

Seven methods of serotyping of Haemophilus influenzae were evaluated. Comparing slide agglutination, staphylococcal coagglutination, latex agglutination, counterimmunoelectrophoresis, immunofluorescence, capsular swelling, and cultivation on antiserum agar the commercial coagglutination test was most reliable, most rapid, and easiest to perform. To identify all six serotypes this coagglutination test had to be combined with slide agglutination. With most methods best results were achieved by using cultures incubated at 37 degrees C for 6 h. As nonencapsulated strains often agglutinated unspecifically, selection of probably typeable strains was useful. Differentiation with help of colonial morphology and opalescent growth was facilitated by cultivation on Brain Heart Infusion (BHI) Chocolate Agar and testing of growth factor requirements on translucent BHI Agar with strips containing the growth factors V, X, and VX, respectively. In broth turbid growth was a hint for encapsulation. Nigrosin staining, a negative capsule staining, proved to be useful if specific antisera are not available. From 252 clinical isolates of H. influenzae 216 were not typeable. 36 strains could be serotyped. 27 (75%) belonged to serotype b, 6 (16.6%) were serotype e, 3 (8.3%) were serotype f. Serotype e and f were most difficult to identify. Spectrum of patients and diseases were corresponding to the findings of other authors. Less well-known infections like cellulitis (erysipelas of the cheeks) and arthritis were observed, too. Rapid identification of at least H. influenzae type b could render treatment in some cases more effective by early application of a suitable antibiotic.
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PMID:A comparison between methods of identification and serotyping of encapsulated strains of Haemophilus influenzae. 306 78

The need for complex growth media has complicated routine susceptibility testing of Haemophilus influenzae because of antagonism of certain antimicrobial agents by the medium or because of difficulties in interpretation of growth endpoints. Haemophilus test medium (HTM) is a simple, transparent medium for broth- or agar-based tests with H. influenzae. HTM incorporates Mueller-Hinton medium with additions of 15 micrograms of hematin per ml, 15 micrograms of NAD per ml, and 5 mg of yeast extract per ml as growth-promoting additives. Agar or broth microdilution MICs of 10 antimicrobial agents for a collection of 179 H. influenzae isolates determined by using HTM compared favorably with MICs determined by the conventional agar or broth dilution methods recommended by the National Committee for Clinical Laboratory Standards. Disk diffusion tests performed with HTM allowed accurate categorization of susceptible and resistant strains and were easier to interpret than tests performed with Mueller-Hinton chocolate agar. A particular advantage of HTM was the reliability of broth- or agar-based test results with trimethoprim-sulfamethoxazole. The results of the study suggest modification of current National Committee for Clinical Laboratory Standards MIC-interpretive criteria for H. influenzae with amoxicillin-clavulanate, chloramphenicol, and trimethoprim-sulfamethoxazole. Error rate-bounded analysis of MICs and disk diffusion zone sizes also suggest modified zone-interpretive criteria for ampicillin, amoxicillin-clavulanate, chloramphenicol, and tetracycline with HTM or conventional media. Interpretive zone sizes are newly proposed for cefaclor and rifampin disk diffusion tests.
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PMID:Improved medium for antimicrobial susceptibility testing of Haemophilus influenzae. 350 Sep 65

The ability of 2 brands of growth factor discs (Oxoid and Mast) to identify correctly the growth factor requirements of 41 isolates of Haemophilus paragallinarum and 17 isolates of H. avium was evaluated. The percentage of isolates correctly identified as requiring V factor varied with both the brand of the disc and the medium used. On basic nutrient media both brands gave low percentages of correct results: on Isosensitest Agar (Oxoid) the Oxoid discs gave 26% and the Mast discs 24% while on Heart Infusion Agar (Gibco) the Oxoid discs gave 54% and the Mast discs 28%. However, on a more complex medium (TM/S) the percentage of correct results was considerably higher with the Oxoid discs 100% and the Mast discs 52% accurate.
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PMID:An evaluation of commercial discs for the determination of the growth factor requirements of avian haemophili. 398 5

The antibacterial activity of ciprofloxacin was compared to those of norfloxacin, pefloxacin, pipemidic acid, nalidixic acid, nitrofurantoin, sulfamethoxazole, trimethoprim, cephradine and amoxycillin. Agar dilution tests were performed with 631 clinical isolates from urinary and respiratory tract infections. Ciprofloxacin was found to be the most active drug tested against all gram-negative organisms and streptococci, with the exception of Streptococcus faecalis and Streptococcus pneumoniae. MIC 90 values of ciprofloxacin were as follows: for Enterobacteriaceae, 0.03-0.23 mg/l, Pseudomonas aeruginosa, 0.37 mg/l, Haemophilus influenzae, less than 0.015 mg/l, Staphylococcus aureus, 0.75 mg/l, Streptococcus pneumoniae, 1.89 mg/l, and Streptococcus faecalis, 0.95 mg/l. The inhibitory quotients for urine, serum and bronchial secretion showed that ciprofloxacin had the broadest spectrum of all agents tested and covered and clinically significant bacteria.
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PMID:Comparative in vitro activity of five quinoline derivatives and five other antimicrobial agents used in oral therapy. 623 1

Five tests--satellitism, synthesis of porphyrins, acid production from sucrose, beta-galactosidase activity (ONPG), and indole production--to differentiate between strains of Haemophilus influenzae and strains of V-dependent Haemophilus species were evaluated. Six per cent of strains of H influenzae were misidentified as H parainfluenzae by a test for satellitism using filter paper discs impregnated with X factor, V factor, or both, applied to Columbia Agar. None of seven nutrient agars tested grew Haemophilus species, and determined accurately the X factor requirement. Synthesis of porphyrins from delta-aminolaevulinic acid provided a reliable means of demonstrating that X factor was required. A test for the production of acid from sucrose discriminated successfully between strains of V-dependent Haemophilus species (positive) and H influenzae (negative). Most isolates were identified correctly by the ONPG test, but occasional V-dependent strains were negative and could be misidentified as H influenzae. The discriminative value of the indole test was unsatisfactorily low. The results of the tests are discussed in relation to the identification of H influenzae in the diagnostic laboratory.
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PMID:Evaluation of some methods for the laboratory identification of Haemophilus influenzae. 641 74

Agar diffusion tests with metronidazole and tinidazole were performed with one strain each of Bacteroides fragilis and Gardnerella vaginalis (Haemophilus vaginalis, Corynebacterium vaginalis). Their cell morphology was studied 'in situ' on agar surfaces by means of scanning electron microscopy (SEM). A sharp growth end-point was found for B. fragilis, whereas with G. vaginalis there was a gradual decrease in the number and size of the colonies close to the agar well. The SEM study also revealed elongation of the B. fragilis cells when exposed to high concentrations of either drug. No such elongation of G. vaginalis was observed.
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PMID:Scanning electron microscopic examination of Bacteroides fragilis and Gardnerella vaginalis after exposure to concentration gradients of metronidazole and tinidazole. 697 72

A national study was conducted to determine the in vitro activity of 2 newer macrolides, dirithromycin and erythromycylamine compared with that of erythromycin, tetracycline and penicillin. Nineteen major teaching hospitals participated in the study. Minimal Inhibitory Concentrations (MICs) were determined by agar dilution, mostly using Iso-Sensitest Agar and an inoculum of 10(4) cells per spot. 2284 clinically significant strains were isolated in late 1991 and early 1992, comprising 1736 Gram-positive cocci, 355 Haemophilus influenzae, 97 Moraxella catarrhalis, 32 Listeria monocytogenes, 25 Neisseria meningitidis and 39 Neisseria gonorrhoeae were tested. The study indicates that dirithromycin and erythromycylamine possess antibacterial activity equivalent to that of erythromycin against most Gram-positive cocci and M. catarrhalis. Strains resistant to erythromycin were also resistant to dirithromycin and to erythromycylamine. Tetracycline was as active as the macrolides against both penicillin-resistant and penicillin-susceptible strains of Staphylococcus aureus. Coagulase-negative penicillin-resistant staphylococci, compared with tetracycline, were relatively resistant to the macrolides. H. influenzae was less susceptible than the Gram-positive cocci.
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PMID:Multi-centre collaborative study for the in vitro evaluation of new macrolides dirithromycin and erythromycylamine. Australian Group for Antimicrobial Resistance (AGAR). 760 59

The National Committee for Clinical Laboratory Standards standard broth microdilution method for testing the susceptibility of Haemophilus influenzae to ampicillin, azithromycin, clarithromycin, and telithromycin was evaluated by altering one variable at a time. Variables that were tested included age of colony for inoculum preparation, inoculum density, test medium, incubation atmosphere, and incubation time. For the macrolide, azalide, and ketolide agents, incubation in 5 to 7% CO(2) most significantly affected the MICs, producing nearly twofold increases for clarithromycin and telithromycin and a greater than threefold increase for azithromycin. For ampicillin, a 10-fold increase in inoculum density increased the geometric mean MICs for beta-lactamase-negative strains from 1. 50 to 2.45 microg/ml. In addition, 206 H. influenzae strains were tested for their susceptibilities to the same drugs by the broth microdilution tests in two media, as well as by agar dilution tests, disk diffusion tests, and Etests, on six different agar media. The three standard methods with Haemophilus test medium (HTM) compared favorably with each other except for a high minor discrepancy rate (27%) by the disk diffusion test with ampicillin and clarithromycin. Agar dilution test MICs on the five comparative media were generally higher than those on HTM agar but were only rarely more than one twofold concentration higher. Etest MICs of azithromycin and telithromycin were more than twofold higher than agar dilution and broth microdilution MICs on HTM; ampicillin Etest MICs were nearly twofold lower. The use of media other than HTM agar appears to have a minimal effect on susceptibility test results for the ketolide, azalide, or macrolide drugs that we tested against H. influenzae.
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PMID:Influence of variations in test methods on susceptibility of Haemophilus influenzae to ampicillin, azithromycin, clarithromycin, and telithromycin. 1113 45


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