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

The activity of penicillin G, ampicillin, carbenicillin, ticarcillin, azlocillin, mezlocillin and piperacillin against 102 beta-lactamase-producing, methicillin-sensitive strains of Staphylococcus aureus was determined by agar dilution (method A) and broth microdilution (method B) techniques. By NCCLS breakpoint criteria, 4% of the strains were "sensitive" to penicillin and ampicillin, and almost 100% were "sensitive" to the other drugs when method A was used. Results with method B were only significantly lower as far as the cumulative percentage of strains "sensitive" to azlocillin, mezlocillin and piperacillin was concerned (63-71%). Bactericidal effects at "sensitive" levels were observed in 0-2% (penicillin, ampicillin), 31-35% (carbenicillin, ticarcillin) and 10-14% (azlocillin, mezlocillin, piperacillin). While differences in MIC and MBC levels ranged from 0 to 8 dilution steps, tolerance (a greater than 32-fold difference) was seen in at least 9-22% of all strains (depending on the drug tested); experimental limitations, however, excluded a determination of tolerance in all our strains. In a semi-quantitative nitrocefin assay, "strong" beta-lactamase production was correlated to high MIC and/or MBC levels.
Infection
PMID:Susceptibility and tolerance of beta-lactamase-producing, methicillin-sensitive strains of Staphylococcus aureus towards seven broad-spectrum penicillins. 660 89

Twenty-four patients were treated with moxalactam for 25 serious infections. Nineteen patients were septicemic and 18 presented severe underlying diseases considered to impair the normal response to bacterial pathogens. All of the pathogens had MICs of less than 12 mg/l except one Pseudomonas aeruginosa strain with an MIC of 32 mg/l. The dosage ranged from 3 to 12 g/day; the route of administration was either i.v. or i.m. The duration of treatment was six to 26 days. Six patients had urinary tract infections (three bacteremia), four had pulmonary abscesses (two bacteremia), five had septic thrombophlebitis (five bacteremia) and ten had miscellaneous infections (nine bacteremia). Twenty-two (92%) patients responded favourably. Four patients (16.6%) developed superinfections due to organisms highly resistant to moxalactam: three Streptococcus faecalis, one Bacteroides fragilis and one Aspergillus flavus. Tolerance was good. Nine moderate adverse reactions were observed: three cases of transient eosinophilia, two of phlebitis, three hepatic enzyme alterations and one rash. Moxalactam kinetics were measured in serum from 15 patients with normal renal function after receiving 1 g i.v. over 30 min. The mean peak level after the infusion was 82.8 +/- 12.1 (SE) mg/l; the mean trough level 8 h later was 6.2 +/- 1.7 (SE) mg/l. The serum half-life was 2.6 +/- 0.6 (SE) h for the beta phase. Plasma clearance was 76.8 +/- 8.2 ml/min. Moxalactam was found to be highly effective in the therapy of life-threatening infections.
Infection
PMID:Moxalactam therapy of serious infections. 661 77

Anaerobic bacteria commonly cause soft tissue infections in humans, usually as a result of trauma. Although the susceptibility of some species to antibiotics can be predicted reasonably well, many clinical laboratories can do susceptibility tests more easily than they can correctly identify anaerobes. The broth-disk test is the simplest test for clinical laboratories, and a new standardized MIC method is now available for research laboratories. Several types of experimental anaerobic infections can be initiated in animals, and these infections have been used to test the efficacy of therapeutic regimens. Metronidazole was the most effective, and clindamycin was also very active. Elimination of the anaerobic component of abscesses may be sufficient therapy; it may be possible to ignore the facultative organisms.
Infection 1983
PMID:Therapy of anaerobic infections. 667 96

The penetration of various aminoglycosides into uninfected and infected fluids of steel net cages, implanted subcutaneously into rabbits, was studied. The pharmacokinetics of the antibiotics tested in these fluids were characterized by a peak concentration which was delayed in relation to that in serum after both intramuscular and intravenous administration, and by a slower elimination from cage fluids than from serum. Comparing amikacin, gentamicin, netilmicin and tobramycin, the latter seemed to have a somewhat lower penetrability into uninfected cage fluids. Infection of the cage fluids with gram-negative aerobic bacteria resulted in a reduction of the measurable concentrations of amikacin, gentamicin or netilmicin in the cage fluids when compared to those obtained in uninfected fluids in the same rabbits. Elimination of the aminoglycosides from the infected cage fluids was slower than from the uninfected ones. The lower concentrations of the aminoglycosides in infected cage fluids were considered to be primarily due to a penetration barrier created by the infection. The viable counts in infected cage fluids were only marginally affected in cages where the aminoglycoside concentrations were above the minimum inhibitory concentrations (MIC's) of the aminoglycosides against the bacterial strains used for infection when tested in vitro according to standard techniques. In infected cage fluids the pO2 and pH were low, while the pCO2 was high. The number of viable bacteria was high. These factors, which in vitro increased the MIC's of the agents, and the low concentrations achieved in infected cage fluids could explain the inefficacy of aminoglycoside treatment in this experimental model.
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PMID:Studies on some variables influencing aminoglycoside efficacy in vivo and in vitro. 679 55

We studied the behaviour of 56 clinical isolates of Pseudomonas aeruginosa strains against the following beta-lactam antibiotics: cefotaxime, cefoperazone, cefsulodin, lamoxactam, Ro 13-9904, azlocillin, mezlocillin and ticarcillin. Twenty-six strains were resistant to gentamicin and 30 to gentamicin and/or carbenicillin. The MICs were measured by the serial dilution test on solid agar. Cefsulodin was the most active cephalosporin against carbenicillin-resistant strains (MIC greater than or equal to 128 mg/l); it inhibited 56.6% of these strains at a concentration of 8 mg/l. Azlocillin was the most active penicillin, inhibiting 79.96% of the same strains at a concentration of 64 mg/l. Cefsulodin was the most active cephalosporin against the gentamicin-resistant group of Pseudomonas aeruginosa strains (MIC greater than or equal to 8 mg/l) which were sensitive to carbenicillin (MIC less than or equal to 64 mg/l). It inhibited 100% of the strains at a concentration of 4 mg/l. All of the penicillins studied inhibited all of the strains in this group. The required concentrations were the following: 16 mg/l for azlocillin, 32 mg/l for mezlocillin and 64 mg/l for ticarcillin.
Infection 1982
PMID:The in vitro activity of beta-lactam antibiotics against gentamicin and/or carbenicillin-resistant Pseudomonas aeruginosa strains. 681 57

Fifteen strains of Bacteroides fragilis, five highly resistant, five moderately resistant and five sensitive to benzylpenicillin and cephaloridine, were tested for beta-lactamase production. In the highly resistant and the moderately resistant groups of strains, a correlation between formation of beta-lactamase and MIC-values was found. Culture under controlled conditions in stirred fermentors gave higher yields of beta-lactamase than static cultures in bottles. The enzyme had its maximum activity at pH 5.0 and was stable between pH 5.5-8.5. Isoelectric focusing in polyacrylamide gels gave an isoelectric point of 4.9 +/- 0.2 for the enzyme. In the presence of the beta-lactamase inhibitors clavulanic acid and CP-45.899 at concentrations of 1 microgram/ml, the susceptibility to cephaloridine increased fourfold or more in the beta-lactamase-producing strains. Crypticity measurements (beta-lactamase activity broken/intact cells) with cephaloridine as substrate could indicate a diffusion barrier in the cell wall.
Infection 1980
PMID:Studies on beta-lactamase in Bacteroides fragilis. 696 92

Thirty male patients with chronic tonsillitis and 30 male patients with chronic Sinusitis maxillaris were pre-treated for four days with either 2 X 1 g erythromycin daily per os or 3 X 0.75 g amoxicillin daily per os in an open and randomised comparative study. MIC values for the relevant bacteria were determined beforehand. The intended tonsillectomy or radical operation was performed on the third day of pre-treatment, circa 1.5 h after the final administration of antibiotics. The tonsils or the sinus membrane were examined bacteriologically; the concentrations of erythromycin or amoxicillin were determined. At the same time, the concentration of the antibiotic administered was determined in the serum. The average concentration of erythromycin in the tonsil tissue was 1.24 micrograms/g; it was 1.21 micrograms/g in the sinus membrane. Amoxicillin was found at a concentration of 0.17 microgram/g in the tonsil tissue, and 0.1 microgram/g in the sinus membrane. While the levels of erythromycin in the tissue generally equalled or exceeded the MIC value for the pathogen in question, the levels of amoxicillin only reached the relevant MIC value for the given pathogen in a few cases since the concentration in the tissue was insufficient. The clinical tolerance of both antibiotics was good.
Infection 1982
PMID:[Concentrations of erythromycin and amoxicillin in tonsil and sinus tissues of patients with tonsillitis and sinusitis. A comparison (author's transl)]. 704 57

The MICs and MBCs of mecillinam, ticarcillin, mezlocillin, azlocillin and piperacillin were determined by the microdilution method in liquid medium using 700 strains of gram-negative bacilli and enterococci isolated from pathological sources and classified as a function of their sensitivity to ampicillin and carbenicillin. The ampicillin and carbenicillin-sensitive strains were generally sensitive to the other penicillins, although there were differences in activity. The ampicillin and carbenicillin-resistant strains of Escherichia coli that produce a TEM-type penicillinase were sensitive to mecillinam. Mezlocillin, piperacillin and azlocillin had MICs of between 32 and 64 mg/l for 40% of these strains. The Klebsiella strains, whose broad-spectrum penicillinase deactivates ampicillin and carbenicillin, remained sensitive to mecillinam. Mezlocillin, azlocillin and piperacillin had MICs of less than 8 mg/l for 50% of these strains. The carbenicillin-resistant strains of Enterobacter and Citrobacter were also resistant to the other penicillins. Piperacillin and mezlocillin displayed some activity against certain strains of carbenicillin-resistant Serratia, Proteus and Acinetobacter. Azlocillin, piperacillin and, to a lesser degree, mezlocillin were active against the strains of Pseudomonas, for which carbenicillin had an MIC of about 512 mg/l. Ampicillin, mezlocillin and azlocillin showed the best activity against the enterococci, against which mecillinam was inactive. The MBC of these antibiotics is greatly influenced by the density of the bacterial inoculum.
Infection 1982
PMID:Comparative in vitro antibacterial activity of seven semi-synthetic penicillins against aerobic gram-negative bacteria and enterococci. 715 90

The chemotherapy of septicaemia in newborns differs fundamentally from that in older children or adults because, although newborns have a fully developed immunological system, the system has not yet "learned" to operate completely. Ultimately, optimal chemotherapy can only be found empirically. In this respect a few basic guidelines can be given however: 1. The initial therapy must bring the pathogen under control with a high degree of certainty, since a correction in therapy following pathogen indentification is usually too late. 2. Since the pharmacokinetics of antibiotics in newborns vary considerably, the minimal peak serum concentration observed should exceed the MIC of the pathogen. 3. In rapidly maturing newborns and premature babies the pharmacokinetics of each antibiotic must be known precisely. 4. Since in the individual case there can never be absolute certainty with respect to the three above-mentioned problems, combination therapy should be given at all times.
Infection 1980
PMID:Guidelines for adequate chemotherapeutic dosage in newborns and infants with septicaemia and meningitis. 739 19

From 1975 through 1978 isolates from 21 of 230 (9%) Staphylococcus aureus bacteremias were resistant to gentamicin and clindamycin. Gentamicin- and clindamycin-resistant S aureus (GCRS) accounted for 23% of all S aureus isolates from 1977 compared with 2 to 6% in the two years immediately preceding, and the year following 1977. When compared with patients with gentamicin- and clindamycin-sensitive S aureus (GCSS) from 1977, GCRS were more often isolated from patients who acquired their infections in the hospital, particularly in the intensive care unit. A significant association existed between prior or concurrent therapy with gentamicin and/or clindamycin and the isolation of GCRS. Infection with GCRS was associated with a 73% mortality rate versus 28% with GCSS. GCRS were susceptible to oxacillin, cephalothin, tetracycline, and vancomycin. GCRS were resistant to kanamycin and tobramycin but were susceptible to amikacin (median MIC of GCRS, 4.0 microgram/ml). Multiple bacteriophage types of S aureus were involved, and resistance appeared to be plasmid-mediated. A survey of antibiotic usage showed that in comparison to January 1977, a mikacin usage increased and gentamicin usage decreased in March 1979. Because of the popularity of the combination of clindamycin and gentamicin for therapy of life-threatening infections, clinicians should be aware of potential gentamicin- and clindamycin-resistance in S aureus.
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PMID:Gentamicin- and clindamycin-resistant Staphylococcus aureus. 742 69


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