UNIPROT:Q29983 - FACTA Search

Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Target Concepts:

Query: UNIPROT:Q29983 (MIC)
21,138 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to evaluate whether pre-exposure of bacteria to a subinhibitory concentration (sub-MIC) of loracarbef (LY 163892) or daptomycin (LY 146032) could modify bacterial susceptibility to serum bactericidal activity and to phagocytosis and killing by murine peritoneal macrophages and by human polymorphonuclear leucocytes. Escherichia coli, Haemophilus influenzae type b and Staphylococcus aureus grown in the presence of one quarter the MIC of loracarbef, and S. aureus exposed to one quarter the MIC of daptomycin were phagocytosed and killed in numbers significantly higher than non-exposed bacteria. Pre-exposure to loracarbef resulted in increased susceptibility of E. coli and H. influenzae type b to the bactericidal activity of antiserum, but exposure to loracarbef or daptomycin did not modify serum sensitivity of S. aureus. Loracarbef treatment and antiserum enhanced phagocytosis and killing of E. coli and H. influenzae type b to a greater extent than either antibiotic treatment or antiserum alone. These data indicate that loracarbef and daptomycin at sub-MIC enhance the susceptibility of bacterial pathogens to cellular and host defence mechanisms.
...
PMID:Influence of subinhibitory concentrations of loracarbef (LY 163892) and daptomycin (LY 146032) on bacterial phagocytosis, killing and serum sensitivity. 217 52

A 10-year-old boy presented with nuchal rigidity and cerebrospinal fluid (CSF) leukocytosis initially and again on day 6 of intravenous cefuroxime therapy (200 mg/kg/day). Both CSF specimens yielded nontypable beta-lactamase-negative Haemophilus influenzae that were susceptible by disk tests but relatively resistant to cefuroxime (MIC, 8- to 16-fold greater than that of control isolates). To define the mechanism of resistance, the cefuroxime resistance marker was transformed to a susceptible H. influenzae recipient; inactivation and permeability of beta-lactam substrate were tested and the penicillin-binding protein (PBP) profiles were examined. Inactivation of beta-lactam substrate was not detected and reduced permeability was not found. However, reduced beta-lactam binding to PBPs 4 and 5 was observed; 18- to 27-fold more penicillin and 2.5-to 4-fold more cefuroxime was required to saturate or block 50% of the binding sites of these PBPs, respectively. Thus, reduced affinity of PBPs 4 and 5 for beta-lactam substrate appears to be the mechanism of cefuroxime resistance in this strain. The reduced affinity of these targets appears to have contributed to the bacteriologic and clinical failure in this patient.
...
PMID:Cefuroxime treatment failure of nontypable Haemophilus influenzae meningitis associated with alteration of penicillin-binding proteins. 223 Feb 38

We determined the MICs of ampicillin, methicillin, cefaclor, cefixime, cefteram, ofloxacin and ciprofloxacin against a total of 1,448 strains from 11 species: 464 strains of Staphylococcus aureus, 306 strains of Streptococcus pneumoniae, 114 strains of Streptococcus pyogenes, 37 strains of Branhamella catarrhalis, 329 strains of Haemophilus influenzae, 32 strains of Escherichia coli, 66 strains of Klebsiella pneumoniae, 26 strains of Enterobacter cloacae, 20 strains of Serratia marcescens, 12 strains of Pseudomonas aeruginosa and 42 strains of Acinetobacter calcoaceticus, isolated from the throat swab and the sputum of 2,539 patients with respiratory infections who visited 21 private clinics in Tohoku district of Japan during the period from January to April in 1989. Ciprofloxacin and ofloxacin were more active against S. aureus, B. catarrhalis, P. aeruginosa and A. calcoaceticus than other antibiotics. Ampicillin and cefteram were more active against S. pneumoniae and S. pyogenes than other antibiotics. New-quinolones and cephems of new-generation were active against H. influenzae, E. coli, K. pneumoniae, E. cloacae and S. marcescens. Of 30 strains of S. aureus which were resistant (MIC greater than or equal to 12.5 micrograms/ml) to ampicillin, only one strain was resistant (MIC greater than or equal to 12.5 micrograms/ml) to methicillin. Twenty strains (6.5%) of S. pneumoniae and 49 strains (14.9%) of H. influenzae were resistant (MIC greater than or equal to 1.56 micrograms/ml) to ampicillin. Of 101 strains of H. influenzae of which their beta-lactamase activity was determined by Nitrocephin-method, 27 (26.7%) were beta-lactamase-positive strains. The above results indicated that MRSA is only rarely found in primary care clinics but the incidence of ampicillin-resistant H. influenzae in primary care clinics is almost the same as that of the intensive care clinic, i.e. medical school-affiliated hospitals. Therefore caution should be exercised as regards antibiotic resistance of the causative organism even in primary care clinics.
...
PMID:[Studies on respiratory infections in primary care clinic (IV). Antibiotic sensitivity of bacteria isolated from patients with respiratory infections visiting 21 private clinics in the Tohoku District of Japan]. 224 94

We evaluated the consequences of prolonging the time between initial bacterial inoculum suspension preparation and susceptibility test inoculation. Extending the current National Committee for Clinical Laboratory Standards-recommended time of 15 min between suspension preparation and test inoculation should allow laboratories more flexibility to optimize efficiency from the standpoint of workflow. We assessed the length of time for which viable-bacterium counts remain stable in three liquid media at room temperature. Fifty isolates were examined in water, saline, and cation-supplemented Mueller-Hinton broth (CSMHB). Disk diffusion and microdilution MIC tests were performed on nine of these. Our results suggest that directly prepared inoculum suspensions of members of the family Enterobacteriaceae, Pseudomonas aeruginosa, staphylococci, and enterococci can be held for up to 6 h in water or saline prior to inoculation of disk diffusion and MIC tests without compromising test accuracy. The same organisms can be held for at least 1 h in CSMHB. Viridans group streptococci can be held for up to 6 h in saline and CSMHB and for up to 3 h in water. Similarly, Haemophilus influenzae and Streptococcus pneumoniae isolates may be held in CSMHB for up to 3 h. Because of an early decrease in viable-bacterium counts in water and saline with some H. influenzae and S. pneumoniae isolates, we recommend that National Committee for Clinical Laboratory Standards recommendations be followed for these species.
...
PMID:Stability of viable-bacterium counts in liquid media used for preparation of inocula and subsequent impact on antimicrobial susceptibility test results. 238 Mar 55

On the basis of preliminary in vitro data, we evaluated E-1040, a new cephalosporin, against 188 cystic fibrosis (CF) sputum isolates obtained from 26 CF centers in the United States. These isolates included mucoid and nonmucoid Pseudomonas aeruginosa, Pseudomonas cepacia, Staphylococcus aureus, Haemophilus influenzae, and Escherichia coli. In addition to MICs measured under standard conditions, selected isolates were tested at various pH values, inoculum sizes, and diluent (CF serum and sputum) conditions. E-1040 activities (MICs for 50 and 90% of the strains) against the isolates were as follows: P. aeruginosa (mucoid and nonmucoid), 1 and 4 micrograms/ml; P. cepacia, 4 and 16 micrograms/ml; S. aureus, 8 and 8 micrograms/ml; H. influenzae, 1 and 4 micrograms/ml; and E. coli, less than or equal to 0.12 and less than or equal to 0.12 microgram/ml. E-1040 activity against mucoid P. aeruginosa was 4-fold greater than that of aztreonam, 16-fold greater than that of ceftazidime, and 32-fold greater than that of piperacillin. E-1040 was similar to other broad-spectrum cephalosporins against S. aureus, H. influenzae, and E. coli. Bactericidal activity was less than or equal to 1 dilution of MIC for 88% of the strains, although kinetic studies with mucoid strains of P. aeruginosa demonstrated effective killing only at eight times the MIC. Variations in pH from 5 to 8, in inoculum size from 10(3) to 10(7) CFU/ml, and in diluent (CF serum or CF sputum) did not affect E-1040 activity.
...
PMID:In vitro activity of E-1040, a 3-substituted cephalosporin, against pathogens from cystic fibrosis sputum. 238 68

A foremost mechanism of bacterial resistance to penicillin and its derivatives is the chromosomal or plasmid mediated production of B-lactamase. Inhibitors of these enzymes like sulbactam may help overcome this problem. We tested the in vitro activity of ampicillin alone or in association with sulbactam (1:1 ratio) against enterobacteriaceae, aeromonae, Hemophilus influenzae, staphylococci and Streptococcus fecalis, isolated from patients suffering different infectious diseases. The Kirby-Bauer method was used to evaluate susceptibility and MIC was determined by agar dilution techniques. Most enterobacteriaceae and aeromonae were resistant to ampicillin. The association was effective against shigellae and Yersinia enterocolitica. 28% of H. influenzae strains were resistant to ampicillin alone but were susceptible to the association. 30% of resistant staphylococci became sensitive to the association.
...
PMID:[In vitro activity of ampicillin and ampicillin-sulbactam on diverse bacteria]. 251 28

The combination of piperacillin and the beta-lactamase inhibitor tazobactam (formerly YTR 830) was studied to determine optimal disk concentrations and dilution testing conditions. In addition, the potency of the combination was compared to that of piperacillin alone. The spectrum of piperacillin was greatly expanded by the addition to tazobactam principally against beta-lactamase producing strains of Haemophilus influenzae, Escherichia coli, Morganella morganii, Proteus vulgaris, Providencia stuartii, Shigella spp., Neisseria gonorrhoeae, and Staphylococcus spp. Tazobactam was active alone against Branhamella catarrhalis (minimum inhibitory concentration [MIC] 50, less than or equal to 1 microgram/ml), gonococci (MIC 50, 0.5-4 micrograms/ml), and N. meningitidis (MIC 50, less than or equal to 1 microgram/ml). Studies with beta-lactamase-producing type strains showed tazobactam to have high affinity for plasmid-mediated enzymes (TEM-1 and 2, SHV-1, HMS-1, and some CARB or OXA types) and not chromosomal beta-lactamases. Piperacillin/tazobactam inhibited 93% of fluoro-quinolone resistant strains at less than or equal to 64/8 micrograms/ml but failed to suppress the growth of 15 strains producing stably depressed cephalosporinases. Comparisons of piperacillin/tazobactam results determined with 100/10-, 100/20-, and 100/30-micrograms disks established the 100/10-micrograms disk as most usable. Among five different MIC combinations the ratio of eight parts piperacillin to one part tazobactam or fixed concentration tests at greater than or equal to 4 micrograms tazobactam/ml were preferred, each producing very low occurrences (less than or equal to 1.6%) of false-resistance or -susceptibility when compared to disk test results. MICs determined by agar and broth microdilution methods were essentially the same. The recommended breakpoints for piperacillin/tazobactam MICs were identical to those now found in the NCCLS susceptibility testing standards with the following exceptions: (1) for tests with H. influenzae and Staphylococcus spp.--susceptible at greater than or equal to 21 mm (MIC less than or equal to 16/2 micrograms/ml) and resistant less than or equal to 20 mm (MIC less or equal to 32/4 micrograms/ml); and (2) all remaining nonspeudomonas isolates would be interpreted by the NCCLS piperacillin enteric bacilli susceptibility criteria. This newer beta-lactamase inhibitor combination appears to be worthy of further in vivo trials guided by these or similar tentative in vitro susceptibility testing parameters.
...
PMID:Studies to optimize the in vitro testing of piperacillin combined with tazobactam (YTR 830). 256 Apr 22

The antimicrobial activities of cefixime, cefpodoxime, and ceftibuten were determined with 18 ampicillin-susceptible (Amps), 13 ampicillin-resistant beta-lactamase-producing (AmprBLP), and 7 ampicillin-resistant non-beta-lactamase-producing (AmprNBLP) strains of Haemophilus influenzae. An effect of inoculum density on apparent MIC, the bactericidal activity of these agents, and the targets of the three cephems were determined. The MICs of cefixime, cefpodoxime, and ceftibuten for 90% of the Amps and AmprBLP isolates were 0.04, 0.08, and 0.08 microgram/ml, respectively. In contrast, the MICs for 90% of the AmprNBLP strains were 0.96, 1.92, and 7.68 micrograms/ml. No significant inoculum effect was observed for any group of strains comparing inocula of 10(3) and 10(5) CFU, whereas only the AmprNBLP isolates showed a marked effect at an inoculum of 10(6) CFU. Although bactericidal levels were achieved for the Amps and AmprBLP strains, tolerance to cefixime and ceftibuten was observed. The bactericidal activity for the AmprNBLP strains was limited, with cefixime showing the highest activity of the three cephems. Penicillin-binding proteins 2, 4, and 5 revealed high affinity, with 50% inhibitory concentration levels below the MIC for all three cephems, suggesting that these are important targets of these agents in H. influenzae. We conclude that the cephems are highly active in vitro against Amps and AmprBLP strains of H. influenzae, but less so against AmprNBLP isolates.
...
PMID:In vitro activities and targets of three cephem antibiotics against Haemophilus influenzae. 261 Apr 99

Enlisting the help of various research institutions across the nation, Ikemoto et al. have been pooling cultures of clinical isolates of respiratory tract infections and mapping out the correlations between patient backgrounds and the causative bacteria and the changes in the sensitivity spectra of the bacteria to various antibacterial and antibiotic agents annually since 1981. The following is a report of the 1986 findings. During the period from September, 1986 to March, 1987, 558 cases of respiratory infections were reported at 17 institutions across the nation and a total of 657 apparent causative strains were isolated from sputum samples. Of these strains, 75 strains of Staphylococcus aureus, 108 of Streptococcus pneumoniae, 150 of Haemophilus influenzae, 107 of Pseudomonas aeruiginosa (non-mucoid production type), 21 of P. aeruginosa (mucoid production type), 32 of Klebsiella pneumoniae, 8 of Escherichia coli, and 55 of Branhamella catarrhalis were subjected to MIC determination of various antibacterial and antibiotic agents to map drug sensitivities. In addition, diagnoses, age distributions by diagnoses, frequencies of infectious diseases, types of isolated bacteria, and usage statuses of the antibacterial and antibiotic agents the times of at isolation were also investigated. MIC determinations were carried out to investigate susceptibilities of causative organisms of respiratory tract infections to various antibacterial and antibiotic agents. From the 558 cases of respiratory tract infections, 657 strains were detected at concentrations not less than 10(4-6)/ml and identified to be the causative organisms. Of these strains, 603 could be used for MIC determination. An overwhelming majority of major causative bacteria, inclusive of H. influenzae and S. pneumoniae, showed sensitivity patterns similar to the sensitivity patterns found a year earlier, P. aeruginosa alone, however, showed some increase in its susceptibility to penicillin and cephem antibiotics. Regarding patient backgrounds, the age distribution was heavily biased towards the higher end of the scale, which patients with ages of 50 or higher accounting for 77.9%, compared to 73.5% in 1985. When the patients were classified by diagnoses, chronic bronchitis, bacterial pneumonia and bronchiectasis accounted for the majority of the infections: 28.7%, 23.3%, and 19.0%, respectively. The percentages of chronic bronchitis and bacterial pneumonia 28.7% and 23.3%, respectively, were somewhat higher in 1986 than in 1985. The disease which was comparatively frequent in all age groups was bronchiectasis, which accounted for 44.0% in patients with ages 29 years or lower, 18.4% in patients between 30 years and 69 years, and 16.7% in patients with ages 70 years or higher. The next most frequent infection was bacterial pneumonia.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:[Susceptibility of bacteria isolated from patients with lower respiratory tract infections to antibiotics (1986)]. 269 57

This ether oxim derivative of erythromycin A is an easy to absorb oral antimicrobial somewhat less effective in vitro than erythromycin. At relatively low MIC's it is active against staphylococci, streptococci, pneumococci, branhnamella and chlamydiae, higher concentrations are needed against enterococci and some strains of H. influenzae. Roxithromycin is also reported to have a very good effect on campylobacters, many anaerobic bacteria, Toxoplasma gondii, Treponema pallidum, Mycoplasma pneumoniae and Legionella pneumophilla. Its half-life in the serum of healthy individuals ranges from 9 to 16 hours. Maximum serum concentrations at 2 oral doses of 150 mg a day are reached at 3 to 4 days and vary from 5.5 to 11.1 mg/l. The distribution of roxithromycin in body tissues is excellent. In a group of 57 patients treated for various infections of clear etiology the positive therapeutic effects resulting in the state of bacteriological negativity was reached in 86% of cases. Roxithromycin can be recommended as a drug of choice in mild or less severe cases of infection caused by agents sensitive to this antimicrobial. Its excellent tolerance makes it especially well suited for use in pediatric practice.
...
PMID:Roxithromycin--a new macrolide derivative. 269 62

<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>