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Biomedical subjects

M R Jacobs

Publications and source records attributed to M R Jacobs.

At least 109 records · Page 6Linked to original sources
PubMed1998

Postantibiotic effect of trovafloxacin against gram-positive and -negative organisms.

Trovafloxacin pneumococcal and staphylococcal postantibiotic effects (PAEs) were 0.7 to 1.8 and 0.7 to 2.4 h, respectively. For Escherichia coli and Pseudomonas aeruginosa, PAEs were 2.4 to 4.4 h. Pneumococcal and staphylococcal postantibiotic sub-MIC effects (PA-SMEs) (0.4 times the MIC) were 2.3 to 3.7 and 2.4 to > 9.2 h, respectively, and E. coli PA-SMEs (0.3 times the MIC) were 6.8 to > 12.0 h. For one P. aeruginosa strain, the PA-SME (0.4 times the MIC) was > 10 h; in the other, rapid bactericidal activity precluded measurement.

Anti-Infective Agents↗
PubMed1998

Activities of three quinolones, alone and in combination with extended-spectrum cephalosporins or gentamicin, against Stenotrophomonas maltophilia.

The present study examined the activities of trovafloxacin, levofloxacin, and ciprofloxacin, alone and in combination with cefoperazone, ceftazidime, cefpirome, and gentamicin, against 100 strains of Stenotrophomonas maltophilia by the MIC determination method and by synergy testing of the combinations by the time-kill and checkerboard titration methods for 20 strains. The respective MICs at which 50% and 90% of isolates were inhibited for the drugs used alone were as follows: trovafloxacin, 0.5 and 2.0 microg/ml; levofloxacin, 2.0 and 4.0 microg/ml; ciprofloxacin, 4.0 and 16.0 microg/ml; cefoperazone, >128.0 and >128.0 microg/ml; ceftazidime, 32.0 and >128.0 microg/ml; cefpirome, >128.0 and >128.0 microg/ml; and gentamicin, 128.0 and >128.0 microg/ml. Synergistic fractional inhibitory concentration indices (</=0.5) were found for >/=50% of strains for trovafloxacin-cefoperazone, trovafloxacin-ceftazidime, levofloxacin-cefoperazone, levofloxacin-ceftazidime, ciprofloxacin-cefoperazone, and ciprofloxacin-ceftazidime, with other combinations affecting fewer strains. For 20 strains tested by the checkerboard titration and time-kill methods, synergy (>/=100-fold drop in count compared to the count achieved with the more active compound) was more pronounced after 12 h due to regrowth after 24 h. At 12 h, trovafloxacin at 0.004 to 0.5 microg/ml showed synergy with cefoperazone for 90% of strains, with ceftazidime for 95% of strains with cefpirome for 95% of strains, and with gentamicin for 65% of strains. Levofloxacin at 0.03 to 0.5 microg/ml and ciprofloxacin at 0.5 to 2.0 microg/ml showed synergy with cefoperazone for 80% of strains, with ceftazidime for 90 and 85% of strains, respectively, with cefpirome for 85 and 75% of strains, respectively, and with gentamicin for 65 and 75% of strains, respectively. Time-kill assays were more discriminatory than checkerboard titration assays in demonstrating synergy for all combinations.

Anti-Infective Agents↗
PubMed1998

Activities of gatifloxacin compared to those of seven other agents against anaerobic organisms.

The agar dilution MIC was used to compare activities of gatifloxacin with those of ciprofloxacin, sparfloxacin, trovafloxacin, ampicillin, ampicillin-sulbactam, clindamycin, and metronidazole against 351 anaerobes. Overall MICs at which 50% of the isolates are inhibited and MICs at which 90% of the isolates are inhibited (in micrograms per milliliter) were as follows: gatifloxacin, 0.5 and 4; ciprofloxacin, 2 and 32; sparfloxacin, 2 and 8; trovafloxacin, 1 and 4; ampicillin, 1 and 64; ampicillin-sulbactam, 0.5 and 4; clindamycin, 0.125 and 8; and metronidazole, 1 and >16, respectively. Gatifloxacin MICs were similar to those of trovafloxacin in all organism groups.

Anti-Infective Agents↗
PubMed1998

Determination of penicillin MICs for Streptococcus pneumoniae by using a two- or three-disk diffusion procedure.

The potential for the use of the disk diffusion method to accurately predict penicillin MICs for Streptococcus pneumoniae was investigated with penicillin (6 microg), methicillin (5 microg), and oxacillin (1 microg) disks. A total of 183 S. pneumoniae isolates were tested by three MIC procedures (agar dilution, microdilution, and E-test). Regression analyses of the geometric mean of the three MIC results against (i) the sum of the zone diameters for methicillin, penicillin, and oxacillin disks; (ii) the sum of the zone diameters for methicillin and penicillin disks; and (iii) each of the three individual zone diameters were performed. Calculated MICs were determined from each of these regression analyses and compared to the mean reference MICs. A high level of correlation was obtained with both the two- and the three-disk procedures (r = 0.97), with essential agreement rates (+/-1 doubling dilution) between MICs calculated by the three-disk procedure and the two-disk procedure and the mean reference MICs of 98.4 and 98.9%, respectively. No major or very major errors were obtained with the two- or three-disk procedures. The accuracy of the disks used individually was lower (r = 0.84 to 0.93). However, oxacillin and methicillin disk testing remain excellent for screening strains, with all penicillin-susceptible strains having zones of >21 and >22 mm, respectively. The combination disk procedure, which involves the use of three disks (methicillin, oxacillin, and penicillin) or two disks (methicillin and penicillin) for testing S. pneumoniae, can provide accurate penicillin MICs and qualitative category results that are comparable to results obtained by the E-test, agar, and microdilution MIC methods.

Diffusion↗
PubMed1998

Lack of utility of the lysis-centrifugation blood culture method for detection of fungemia in immunocompromised cancer patients.

We retrospectively compared the utility of a fungal isolation device (Isolator) versus conventional techniques for recovering fungal organisms from blood cultures obtained from neutropenic cancer patients. Positive cultures were deemed true pathogens, possible pathogens, or contaminants according to laboratory and clinical criteria. Fifty-three patients had 66 positive blood cultures for fungi, nine on multiple occasions. In 20 episodes true pathogens were recovered, 6 from broth medium alone, 4 from the Isolator system alone, and 10 from both systems. False-negative cultures were noted in 4 of 20 (20%) cases in which broth medium was used and in 6 of 20 (30%) cases in which the Isolator system was used. Possible pathogens were detected in 4 of 66 blood culture-positive cases. Forty-two positive cultures were considered contaminants, 1 collected from standard medium and 41 of 42 (98%) which grew only in Isolators. Eleven of 18 patients with true fungal infections expired as a result of infection, while 4 of 33 patients with a contaminant expired, none from a fungal cause. We do not advocate the routine use of Isolator tubes in the evaluation of the febrile, neutropenic patient due to the high rates of false positives and of contamination.

Adult↗
PubMed1998

Antipneumococcal activities of levofloxacin and clarithromycin as determined by agar dilution, microdilution, E-test, and disk diffusion methodologies.

The activities of levofloxacin and clarithromycin against 199 penicillin- and macrolide-susceptible and -resistant pneumococci were tested by agar and microdilution methods in air and by disk diffusion and E-test methods in air and CO2. For levofloxacin, >/=99. 0% of strains were susceptible at </=2.0 microgram/ml with zone diameters of >/=17 mm, regardless of incubation in air or CO2. Although zone sizes were smaller and E-test MICs were higher for clarithromycin in CO2 than those in air, category differences were minor, and susceptibility rates for clarithromycin were similar to those obtained by agar and microdilution in air (range, 76.9 to 80.9% by all methods). For clarithromycin, adjustment of breakpoints based upon distribution of results resulted in susceptibility rates which were similar by all methods (75.8 to 76.9% susceptible, 0 to 1.5% intermediate, 22.6 to 23.1% resistant). Minor discrepancies were obtained with levofloxacin for one strain (0.5%) by microdilution and two strains (1.0%) by disk diffusion in CO2. For clarithromycin, minor discrepancies were found in three strains (1.5%) by microdilution, seven strains (3.5%) by agar dilution, four strains (2.0%) by E-test in air, six strains (3.0%) by disk diffusion in air, and five strains (2.5%) by disk diffusion in CO2. Major discrepancies occurred with levofloxacin in one strain (0.5%) by microdilution but were not found with clarithromycin. Very major discrepancies were not seen with levofloxacin, but occurred with clarithromycin in five strains (2.5%) by microdilution, three strains (1.5%) by agar dilution, two strains (1.0%) by E-test in air, eight strains (4.0%) by disk diffusion in air, and one strain (0.5%) by disk diffusion in CO2.

Anti-Bacterial Agents↗
PubMed1998

Characterization of depression in Alzheimer's disease by the CERAD Behavior Rating Scale for Dementia (BRSD).

The authors selected 69 participants from an Alzheimer's disease research registry and diagnosed them as depressed or nondepressed by use of a semi-structured clinical interview. Responses to selected BRSD items were compared between the depressed and nondepressed groups. Differences between responses of the two groups on BRSD items related to anxiety and depression were significant. The groups did not significantly differ in their responses to items related to other content areas. On the basis of their responses to the BRSD anxiety and depression items, 70% of participants were correctly classified as depressed or nondepressed.

Adult↗
PubMed1997

A 1994-95 survey of Haemophilus influenzae susceptibility to ten orally administered agents. A 187 clinical laboratory center sample in the United States.

During August, 1994 to April, 1995, a total of 2278 clinical isolates of Haemophilus influenzae were obtained from 187 clinical laboratories in the United States (U.S.). The vast majority of these isolates (75%) were from respiratory sites, and the remaining organisms were from blood, ear, eye, and spinal fluid sources. The overall rate of beta-lactamase production and ampicillin resistance was 36%. The antimicrobial susceptibility of isolates was determined by reference broth microdilution testing against ten orally administered agents. MIC values were compared according to 12 geographical regions, inpatient or outpatient status, gender, and eight age groupings. Modest and occasionally significant differences were observed: 1) greater numbers of beta-lactamase-producing strains among outpatients, in males, in the mid-Atlantic region, and in children < or = 12 years of age; 2) lower prevalence of beta-lactamase-producing isolates in the Southeast and Pacific regions; 3) cefaclor, cefprozil, and loracarbef activity was lowest among the younger children (< or = six years); and 4) macrolide in vitro efficacy was lowest in patients > 50 years of age and in three eastern regions. Overall, more than 99% of the strains were susceptible to amoxicillin/clavulanic acid, cefixime, and cefpodoxime (e.g., widest potential clinical use). Susceptibilities using National Committee for Clinical Laboratory Standards (NCCLS) breakpoint criteria for the other agents were: 96.6% to cefuroxime, 86.5% to loracarbef, 84.0% to clarithromycin, 81.8% to cefaclor, and 80.7% to cefprozil. Non-beta-lactamase mechanisms of resistance to ampicillin were rare (0.2%) or episodic and were attributed to altered penicillin-binding proteins. Although there is an increased prevalence of beta-lactamase production among H. influenzae isolates compared to prior years, four beta-lactams remain highly active (> 95% susceptibility) against contemporary strains of H. influenzae. Other monitored compounds seem to have declined in spectrum and surveillance trials for resistance among H. influenzae isolates should continue in an effort to identify trends in the U.S.

Adult↗
PubMed1997

Evaluation of Haemophilus influenzae isolates with elevated MICs to amoxicillin/clavulanic acid.

A 1994 to 1995 national Haemophilus influenzae surveillance study of 1910 strains showed that 13 strains (0.7%) were resistant to amoxicillin/clavulanic acid (MIC, > or = 8/4 micrograms/ml). These and other selected strains were investigated further in this study. Susceptibility of the surveillance study strains was determined with the commercial microdilution trays used in the original study and in triplicate with reference broth microdilution trays prepared by the investigators, as well as by Etest and disk diffusion. Amoxicillin/clavulanic acid resistance was confirmed for only one of the surveillance study strains. This strain produced double zones of growth with Etest and disk-diffusion methods, with the double zone containing spheroplasts. When the amoxicillin/clavulanic acid MICs of all beta-lactamase positive strains were compared, MIC results obtained with surveillance study trays and the Etest were one to two dilutions higher than MICs obtained with reference trays. The distribution and modal amoxicillin/clavulanic acid MICs of beta-lactamase-positive and -negative strains was essentially the same for a comparison group of strains using reference trays, in contrast to a fourfold higher modal MIC for beta-lactamase-positive strains using surveillance study reagents and strains. These differences in MICs could be attributed to variations in inoculum, the presence of spheroplasts, and/or a difference in potency of amoxicillin and/or clavulanic acid in the tray and Etest reagents used. Methods for assessing the adequacy of the clavulanic acid content are not adequate, amoxicillin control values and a beta-lactamase-positive H. influenzae control strain are required.

Amoxicillin↗
PubMed1997

Susceptibility of twenty penicillin-susceptible and -resistant pneumococci to levofloxacin, ciprofloxacin, ofloxacin, erythromycin, azithromycin, and clarithromycin by MIC and time-kill.

This study uses MIC and time-kill methodology to examine the antipneumococcal activity of levofloxacin, ciprofloxacin, ofloxacin, erythromycin, azithromycin, and clarithromycin against 20 pneumococci. Ten strains had levofloxacin MICs of 1.0 microgram/ml, and ten levofloxacin MICs of 2.0 micrograms/ml. Five strains in each group were macrolide susceptible, and five were macrolide resistant. MICs for ciprofloxacin and ofloxacin ranged from 0.5 to 4.0 micrograms/ml and 1.0 to 8.0 micrograms/ml, respectively. MICs of erythromycin, azithromycin, and clarithromycin were similar for macrolide susceptible strains, ranging between 0.004 to 0.06 microgram/ml, and were > or = 128.0 micrograms/ml for macrolide resistant strains. The three quinolones were bactericidal (99.9% killing) for all macrolide-susceptible strains at 2 x MIC at 24 h. The three quinolones yielded 99% killing of all strains after 12 h at 2 x MIC, and 90% killing of all strains after 6 h at the MIC of levofloxacin and ciprofloxacin and 2 x MIC for ofloxacin. Levofloxacin yielded 90% killing of all strains after 4 h at 2 x MIC and ofloxacin at 4 x MIC. For macrolide-susceptible strains, erythromycin and clarithromycin were bactericidal for 9 of 10 strains after 24 h at 4 x and 2 x MIC, respectively, and azithromycin was bactericidal after 24 h at 2 x MIC for 8 of 10 strains. All three macrolides were bactericidal after 12 h only, while 90% killing occurred in 9 of 10 strains at 8 x MIC after 6 h. Quinolone kill kinetics were similar for the 10 macrolide-resistant strains. For macrolide-resistant strains, at 64 to 128.0 micrograms/ml, virtually no decrease in count was seen, with no bactericidal effect.

Anti-Bacterial Agents↗
PubMed1997

Resistance patterns of streptococcus pneumoniae from carriers attending day-care centers in southwestern Greece.

The resistance to beta-lactam and non-beta-lactam antibiotics of 133 nasopharyngeal isolates of Streptococcus pneumoniae recovered from December 1995 to February 1996 from children attending seven day-care centers in southwestern Greece was studied. Reduced susceptibility to one or more anti-microbial agents was found in 70 isolates (53%), as follows: penicillin, 17% intermediate, 12% resistant; cefotaxime, 10.5% intermediate, 1.5% resistant; trimethoprim-sulfamethoxazole, 8% intermediate, 35% resistant; chloramphenicol, 27% resistant; tetracycline, 29% resistant; and erythromycin/clindamycin, 19% resistant. Eighty-seven percent of penicillin-intermediate or -resistant strains belonged to serogroups/serotypes 19, 21, and 23. Fifty-six percent of the antibiotic-resistant pneumococci were multiply resistant, including serogroup 6 strains that were penicillin-susceptible but resistant to all non-beta-lactam drugs tested, as well as serogroup 23 strains resistant to penicillin, chloramphenicol, tetracycline, and trimethoprim-sulfamethoxazole. The high incidence of antibiotic-resistant pneumococci and the divergent and unique resistance patterns found in this study underline the need for global surveillance of S. pneumoniae to document the evolution and spread of resistant strains and to guide therapy.

Anti-Bacterial Agents↗
PubMed1997

Time-kill studies on susceptibility of nine penicillin-susceptible and -resistant pneumococci to cefditoren compared with nine other beta-lactams.

Broth MIC and time-kill methodology was used to determine the activity of cefditoren relative to those of penicillin G, ampicillin, amoxycillin, WY-49605, cefuroxime, cefpodoxime, cefdinir, cefixime and cefaclor against three penicillin-susceptible, three intermediate and three penicillin-resistant pneumococci. MICs of all agents rose with those of penicillin G. Cefditoren was the most active agent (MICs 0.002-0.5 mg/L), followed by WY-49605 (0.008-1.0 mg/L), amoxycillin (0.015-2.0 mg/L), cefuroxime (0.015-4.0 mg/L), cefpodoxime (0.03-4.0 mg/L), ampicillin (0.015-8.0 mg/L), cefdinir (0.03-16.0 mg/L), cefixime (0.125-64.0 mg/L) and cefaclor (0.5-128.0 mg/L). All beta-lactams were bactericidal at the MIC after 24 h, and produced 90% killing after 12 h at concentrations above the MIC. Bactericidal concentrations of cefditoren, even for penicillin-resistant strains, were < or = 0.5 mg/L at 24 h. Additionally, cefditoren and WY-49605 were the only compounds that killed 99% of all strains after 6 h at > or = 4 x MIC. Cefditoren and amoxycillin killed 90% of all strains at 8 x MIC, and WY-49605 at 4 x MIC, after 4 h. Ampicillin had time-kill kinetics similar to those of amoxycillin, but MICs were 1-2 dilutions higher than the latter drug. Cefuroxime and cefpodoxime were the most active of other oral cephalosporins tested. Cefditoren and WY-49605 had the lowest MICs and most favourable time-kill kinetics of all beta-lactams tested.

Anti-Bacterial Agents↗
PubMed1997

Time-kill study of the activity of trovafloxacin compared with ciprofloxacin, sparfloxacin, metronidazole, cefoxitin, piperacillin and piperacillin/tazobactam against six anaerobes.

A time-kill method was developed to examine the killing kinetics of trovafloxacin, ciprofloxacin, sparfloxacin, metronidazole, cefoxitin, piperacillin and piperacillin/tazobactam against one strain each of Bacteroides fragilis, Bacteroides thetaiotaomicron, Prevotella melaninogenica, Fusobacterium mortiferum, Peptostreptococcus magnus and Clostridium perfringens. Solutions and suspensions were prepared inside an anaerobic glove box, using syringes and prereduced broth. Bottles were then incubated outside the chamber and viability counts determined after incubation for 0, 6, 24 and 48 h in a shaking water bath, avoiding introduction of air. Bacteriostatic/bactericidal concentrations (mg/L) after 48 h for the six strains were: trovafloxacin, 0.03-1/0.03-1; ciprofloxacin, 0.25-16/0.25-32; sparfloxacin, 0.06-2/0.06-8; metronidazole 1-64/1-64; cefoxitin, 0.125-16/0.125-32; piperacillin, 0.125-64/0.125-64; piperacillin/tazobactam, 0.06-2/0.125-8. Bacteriostatic levels were within two dilutions of broth MICs. By this time-kill method, trovafloxacin had the lowest bacteriostatic concentrations of all compounds tested.

Anti-Infective Agents↗
PubMed1997

Activity of new quinolones against intracellular Mycobacterium avium in human monocytes.

The ability to inhibit the in-vitro growth of mycobacteria within human monocytes is a useful screening assay for novel chemotherapeutic agents. In this study the MICs of a panel of new quinolones were determined by the broth microdilution method for two strains of Mycobacterium avium. Sixteen such compounds with MIC90s ranging from 2 to >32 mg/L were subsequently selected for the 7 day monocyte assay using ciprofloxacin for comparison. The degree of inhibition of intracellular growth correlated with the MICs. PD 139586, PD 143289, PD 135144, PD 119421 and PD 131575 were the most active new agents with activities superior to those of ciprofloxacin and sparfloxacin.

Anti-Infective Agents↗
PubMed1997

Variation in erythromycin and clindamycin susceptibilities of Streptococcus pneumoniae by four test methods.

Susceptibilities of 124 strains of Streptococcus pneumoniae to erythromycin and clindamycin were determined by the National Committee for the Clinical Laboratory Standards (NCCLS) broth microdilution method, with incubation for 20 to 24 h in ambient air and with modifications of this method by incubation for up to 48 h in air and CO2. Strains were also tested by agar dilution, E-test, and disk diffusion; good correlation was obtained with these methods, with clear separation into bimodal populations of susceptible and resistant stains. The broth microdilution method, however, using incubation in air for 24 h (NCCLS method), misclassified 4 of 92 erythromycin-resistant strains (1 as susceptible and 3 as intermediate) and 25 of 58 clindamycin-resistant strains (all as susceptible). With the exception of one strain with clindamycin, susceptible and resistant strains were correctly classified by the microdilution method with incubation in CO2 for 24 h or in ambient air for 48 h. Disk diffusion, agar dilution, and E-test methods with incubation in 5% CO2 are therefore reliable methods for susceptibility testing of pneumococci against these agents. However, the NCCLS microdilution method, which specifies incubation for 20 to 24 h in ambient air, produced significant very major errors (43%) clindamycin. Modification of the microdilution method by incubation in 5% CO2 or by extension of incubation time in ambient air to 48 h corrected these errors. Disk diffusion, however, was shown to be a simple, convenient, and reliable method for susceptibility testing of pneumococci to erythromycin and clindamycin and is suggested as the method of choice for these agents.

Anti-Bacterial Agents↗
PubMed1997

MIC and time-kill studies of antipneumococcal activity of GV 118819X (sanfetrinem) compared with those of other agents.

Agar dilution MIC methodology was used to test the activities of GV 118819X (sanfetrinem), ampicillin, amoxicillin, amoxicillin-clavulanate, cefpodoxime, loracarbef, levofloxacin, clarithromycin, ceftriaxone, imipenem, and vancomycin against 53 penicillin-susceptible, 84 penicillin-intermediate and 74 penicillin-resistant pneumococci isolated in the United States. GV 118819X was the most active oral beta-lactam, with MIC at which 50% of the isolates were inhibited (MIC50)/MIC90 values of 0.008/0.03, 0.06/0.5, and 0.5/1.0 micrograms/ml against penicillin-susceptible, -intermediate, and -resistant stains, respectively. Amoxicillin and amoxicillin in the presence of clavulanate (2:1) were the second most-active oral beta-lactams, followed by ampicillin and cefpodoxime; loracarbef was not active against penicillin-intermediate and -resistant strains. Clarithromycin was most active against penicillin-susceptible strains but was less active against intermediate and resistant stains. All pneumococcal stains were inhibited by ceftriaxone and imipenem at MICs of < or = 4.0 and < or = 1.0 micrograms/ml, respectively. The activities of levofloxacin and vancomycin were unaffected by penicillin susceptibility. Time-kill studies of three penicillin-susceptible, three penicillin-intermediate, and three penicillin-resistant pneumococci showed that all compounds, at the broth microdilution MIC, yielded 99.9% killing of all strains after 24 h. Kinetic patterns of all oral beta-lactams, ceftriaxone, and vancomycin were similar relative to the MIC, with 90% killing of all strains first observed after 12 h. However, killing by amoxicillin-clavulanate, imipenem, and levofloxacin was slightly faster and that by clarithromycin was slower than that by the above-described drugs. At 2 x the MIC, more strains were killed earlier than was the case at the MIC, but the pattern seen at the MIC prevailed. When MICs and kill kinetics were combined, sanfetrinem was the most active oral antipneumococcal agent in this study.

Anti-Bacterial Agents↗
PubMed1997

Postantibiotic effect of sanfetrinem compared with those of six other agents against 12 penicillin-susceptible and -resistant pneumococci.

The postantibiotic effect (PAE) and postantibiotic sub-MIC effect (PAE-SME) of sanfetrinem were compared to those of penicillin G, amoxicillin, cefpodoxime, ceftriaxone, imipenem, and clarithromycin against four penicillin-susceptible, four intermediately susceptible, and four resistant pneumococci. The MICs of imipenem were the lowest against all of the strains (0.03 to 0.5 microg/ml), followed by those of sanfetrinem (0.016 to 1.0 microg/ml), amoxicillin and ceftriaxone (0.016 to 2.0 microg/ml), and cefpodoxime (0.03 to 8.0 microg/ml). High-level resistance to clarithromycin (MIC, >64.0 microg/ml) was seen in three selected strains. The PAEs of all of the oral beta-lactams tested were similar for all of the strains, ranging from 1 to 6.5 h. The PAEs of ceftriaxone and imipenem ranged from 1 to 8 h, and those of clarithromycin ranged from 1 to 7 h. The mean PAEs of all of the beta-lactams and clarithromycin were 2.8 to 4.3 and 2.5 h, respectively. PAE-SMEs could not be determined for all of the strains due to complete killing, especially at high subinhibitory concentrations. However, the overall pattern with all of the compounds tested was that PAE-SMEs were longer than PAEs. Measurable PAE-SMEs of sanfetrinem at the three subinhibitory concentrations (0.125, 0.25, and 0.5 times the MIC) were 2 to 7, 2 to 7, and 3 to 6 h, while those of amoxicillin and cefpodoxime were 1 to 7.5, 2 to 4, and 4 to 9 and 2 to 7, 4 to 7, and 4 to 6 h, respectively. Measurable PAE-SMEs of ceftriaxone and imipenem were 1 to 6.5, 2 to 9, and 2 to 9 and 1.5 to 6, 2 to 5.8, and 4 to 7.7 h, respectively. Measurable clarithromycin PAE-SMEs were 1 to 5, 1 to 5, and 1 to 6 h at the three concentrations.

Anti-Bacterial Agents↗