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PubMed1995

Macrolides resistance of common bacteria isolated from Taiwan.

To determine the susceptibility to macrolides of common pathogenic bacteria isolated from Taiwan, the in vitro activities of erythromycin, roxithromycin, azithromycin, clarithromycin, and dirithromycin were tested against 492 clinical isolates of eight different bacteria, collected from the National Taiwan University Hospital. The results showed high minimum inhibitory concentrations (MICs) against most of the tested bacteria. The MIC90s for Staphylococcus aureus (both methicillin-resistant and -sensitive strains), coagulase-negative staphylococci (both methicillin-resistant and -sensitive strains), Streptococcus pyogenes, Streptococcus pneumoniae, enterococci, peptostreptococci, and Bacteroides fragilis were all > or = 256 micrograms/ml. The MIC50s for methicillin-resistant strains of S. aureus and coagulase-negative staphylococci, and enterococci were > or = 256 micrograms/ml. For S. pneumoniae, peptostreptococci, and B. fragilis, the MIC50s were > 8 micrograms/ml. The resistance rates to macrolides were 80% or more in methicillin-resistant staphylococci and about 30% in methicillin-sensitive staphylococci. Around 55% of S. pneumoniae strains and 37 approximately 42% of S. pyogenes strains were resistant to macrolides. Cross-resistance to different macrolides was clearly demonstrated in most of the resistant strains.

Anti-Bacterial Agents↗

PubMed1994

Antimicrobial susceptibility of bacterial isolates in south Sweden including a 13-year follow-up study of some respiratory tract pathogens.

The antibiotic susceptibility of consecutive isolates of the upper respiratory tract pathogens Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis, and Staphylococcus aureus, (100 strains of each species collected each year during March through April 1985, 1988 and 1992) to penicillin V, amoxycillin, cefaclor, cefuroxime, doxycycline, erythromycin, and cotrimoxazole was investigated by MIC determination on PDM and PDM II agar. The MICs of the upper respiratory isolates from 1992 supplemented with 100 isolates each of Escherichia coli, Klebsiella spp., Enterobacter cloacae, Proteus mirabilis and Staphylococcus saprophyticus collected during 1992 were determined against the above antibiotics plus cefadroxil, cefpodoxime, roxithromycin, ciprofloxacin, ofloxacin, and BAY Y 3118. Beta-lactamase production was found in 10% of H. influenzae and 80-90% of S. aureus and B. catarrhalis in 1992. Among H. influenzae isolates, non-beta-lactamase-induced resistance to all beta-lactam antibiotics was first detected in 1988 and amounted to 3% of isolates in 1992. Decreased susceptibility of S. preumoniae to penicillin (> or = 0.12 mg/l), co-trimoxazole > or = 32 mg/l, doxycycline (> or = 2 ml/l) and erythromycin (> or = 1 mg/l) was detected in 11%, 7%, and 8%, respectively, in 1992, which is significantly higher than in previous years at the same laboratory. Decreased susceptibility of S. pyogenes to doxycycline and erythromycin was detected in 11% and 9% in 1992. The two most recently developed antibiotics, cefpodoxime and BAY Y 3118, showed high antibacterial activity. The study emphasizes the need to screen for resistance mechanisms such as beta-lactamase production and lowered penicillin affinity.

Anti-Bacterial Agents↗

PubMed1993

[Laboratory and clinical studies on S-1108 in the pediatric field].

Laboratory and Clinical Studies on S-1108, a new oral cephem antibiotic, were carried out to evaluate its usefulness at a dose between 2 and 4 mg/kg a day for 7 to 14 days in the pediatric field. 1) Pharmacokinetic studies S-1108 at a dose of 2 mg/kg was administered to evaluate the pharmacokinetic parameters in 1 subject. Cmax, T1/2 and AUC were 0.69 hour, 1.42 hours and 2.15 micrograms.hr/ml, respectively. 2) Antimicrobial activities MICs against various clinically isolated organisms (Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Branhamella catarrhalis, Escherichia coli and Haemophilus influenzae) were determined. The MIC values of S-1006 were similar to those of cefteram, the MICs against S. pyogenes, and H. influenzae were < or = 0.025 and 0.10 microgram/ml, respectively. 3) Clinical studies S-1108 was administered to patients with various pediatrics infections in 34 cases (upper respiratory tract infections: 12 cases, lower respiratory tract infections: 5 cases, urinary tract infections: 9 cases, skin and soft tissue infection: 6 cases, otitis media: 2 cases). Clinical efficacy rate was evaluated according to "Standard of clinical evaluation in pediatrics field". The responses were all good or excellent. 4) Side reactions There were no serious adverse reactions in any cases. The above results suggest that S-1108 is potent effective and safe agent in the pediatric field at a dose between 2-4 mg/kg (t.i.d.) a day.

Bacteria↗

PubMed1992

Macrophage response to bacteria: induction of marked secretory and cellular activities by lipoteichoic acids.

Lipoteichoic acids (LTAs) from various bacterial species, including Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Enterococcus faecalis, and Listeria monocytogenes, were examined for the ability to induce secretory and cellular responses in a pure population of bone marrow-derived mononuclear phagocytes. Some of the highly purified LTAs, in particular LTAs from Bacillus subtilis, S. pyogenes, E. faecalis, and Enterococcus hirae, were able to affect each of the macrophage parameters measured, i.e., reductive capacity, secretion of tumor necrosis factor and nitrite, and tumoricidal activity. As after stimulation with whole organisms or other bacterial products, secretion of tumor necrosis factor induced by these LTAs reached its maximum within the first few hours of the interaction, while secretion of nitrite and tumoricidal activity required 24 to 36 h for full expression. Other purified LTAs, i.e., LTAs from Streptococcus sanguis, S. pneumoniae, and L. monocytogenes, as well as lipomannan from Micrococcus luteus affected only some of these parameters, while native LTA from S. aureus was inactive. There was no obvious correlation between biological activity and chain length, kind of glycosyl substituents, glycolipid structures, or fatty acid composition of LTAs. Deacylation of LTAs resulted in a complete loss of activity, and deacylated LTAs did not impair the activity of their acylated counterparts, suggesting that acyl chains may be essential for binding of LTA to the cell surface. The results demonstrate that some LTA species are potent inducers of macrophage secretory and cellular activities.

Animals↗

PubMed1992

[Bacteriological, pharmacokinetic and clinical studies of 5% and 10% granules of cefdinir in the pediatric field].

Bacteriological, pharmacokinetic and clinical studies on cefdinir (CFDN, FK482), a new oral cephalosporin, 5% and 10% granules, were performed in the field of pediatrics. The results are summarized below. 1. Antibacterial activities Antibacterial activities of CFDN against Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis, Escherichia coli and Klebsiella pneumoniae were studied in comparison with those of cefaclor (CCL), cefixime (CFIX) and amoxicillin (AMPC). MIC80's of CFDN against S. aureus, S. pneumoniae, S. pyogenes, H. influenzae, B. catarrhalis, K. pneumoniae and E. coli were 0.78, 0.20, less than or equal to 0.025, 0.39, 0.10, 0.20 and 0.10 micrograms/ml, respectively. These results show that CFDN has high antibacterial activities against these organisms. MIC80's of CFDN against Gram-positive bacteria were similar to those of AMPC, and was lower than those of CCL and CFIX. As for antibacterial activities against Gram-negative bacteria (GNB), the MIC80 of CFIX against H. influenzae was 0.05 micrograms/ml, which was slightly lower than that of CFDN. THe MIC80's of CFDN against other GNB were similar to those of CFIX. 2. Absorption and excretion Blood concentrations and urinary excretion rates of CFDN 5% and 10% granules and 100 mg capsule were determined. The data on CFDN 10% granules were similar to those on CFDN 5% granules. At a dose of 3 mg/kg, peak blood concentrations (Cmax's) of CFDN ranged from 0.20 to 2.12 micrograms/ml with 5% granules and from 0.50 to 1.15 micrograms/ml with 10% granules at 2 to 3 hours after dosing. At a dose of 6 mg/kg, peak concentrations were 0.66-2.06 micrograms/ml and 0.70-1.52 micrograms/ml with 5% granules and with 10% granules, respectively. At 8 hours after dosing, blood concentrations were 0.04-0.54 micrograms/ml at 3 mg/kg and 0.06-0.27 micrograms/ml at 6 mg/kg. Blood half-lives were 1.33-4.36 hours at 3 mg/kg and 1.14-3.27 hours at 6 mg/kg. AUC's were 1.7-11.0 micrograms.hr/ml with 3 mg/kg and 2.4-8.7 micrograms.hr/ml with 6 mg/kg. With administration of single 100 mg capsule, Cmax's, blood concentrations after 8 hours, T1/2's and AUC's were 0.79-1.88 micrograms/ml, 0.20 micrograms/ml, 1.54-2.72 hours, and 5.2 micrograms.hr/ml, respectively. Urinary recovery rates in the first 8 hours ranged from 6.85 to 39.2% with 3 mg/kg and 6.08-25.5% with 6 mg/kg.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

PubMed1999

In vitro activity of quinupristin/dalfopristin against clinical isolates of common gram-positive bacteria in Taiwan.

The MICs of quinupristin/dalfopristin against common Gram-positive bacteria isolated from various clinical specimens at a university hospital in Taiwan were determined by the agar dilution method. The tested bacteria included methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible S. aureus (MSSA), methicillin-resistant Staphylococcus epidermidis (MRSE), methicillin-susceptible S. epidermidis (MSSE), Streptococcus pyogenes, Streptococcus pneumoniae, and Enterococcus faecalis. With the exception of E. faecalis all bacteria were susceptible to quinupristin/dalfopristin. The MIC50 and MIC90 were, respectively, 0.25 microgram/mL and 0.5 microgram/mL for both MRSA and MSSA; 0.25 microgram/mL and 0.5 microgram/mL for MRSE; 0.25 microgram/mL and 0.25 microgram/mL for MSSE; 0.125 microgram/mL and 0.125 microgram/mL for S. pyogenes; and < or = 0.03 microgram/mL and 0.25 microgram/mL for S. pneumoniae. Eighty-two percent of the tested E. faecalis isolates were intermediately resistant or resistant to quinupristin/dalfopristin, with an MIC50 of 2 micrograms/mL and an MIC90 of 4 micrograms/mL. Quinupristin/dalfopristin seems to be a promising antimicrobial agent against common Gram-positive bacteria other than E. faecalis in Taiwan.

Anti-Bacterial Agents↗

PubMed1980

Effect of extracellular serum in the stimulation of intracellular killing of streptococci by human monocytes.

This study shows that the intracellular killing of Streptococcus pyogenes, Streptococcus faecalis, and Streptococcus pneumoniae by human monocytes is stimulated by the extracellular presence of both heat-stable and heat-labile serum factors. A similar kind of stimulation of monocytes has been described in respect of catalase-positive microorganisms. However, killing of these bacteria is negligible in the absence of extracellular serum factors, whereas a large proportion of the ingested catalase-negative bacteria are killed in the absence of such extracellular stimuli. Monocytes from patients with chronic granulomatous disease, which are unable to kill Staphylococcus aureus even in the presence of extracellular serum, killed S. pyogenes equally effectively whether serum was present or absent. This index proved to be the same as that for killing by monocytes of healthy subjects in the absence of serum. Taken together, these results indicate that catalase-negative microorganisms possess some kind of suicide mechanism that leads to the death of these bacteria after their ingestion by monocytes in the absence of an extracellular stimulus. Furthermore, the mechanism by which extracellular serum stimulates intracellular killing probably involves enzymes of the O2-dependent bactericidal mechanisms of the monocytes.

Blood↗

PubMed2003

[Antibacterial activity of oral Cephems against various clinically isolated strains].

We determined the antibacterial activities of oral Cephems against isolated from the patients with the respiratory infections, the urinary tract infections, and infections in the obstetrics field of an adult and a child, during the period from 2002 to 2003; Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae, Branhamella catarrhalis, Klebsiella pneumoniae and Escherichia coli of 40 strains of each, and Peptostreptococcus spp. 22 strains. S. pneumoniae and H. influenzae strains that resistant is regarded were collected mainly, penicillin-intermediate S. pneumoniae (PISP), penicillin-resistant S. pneumoniae (PRSP) and beta-lactamase negative ampicillin-resistant H. influenzae (BLNAR) strains. The MICs of Cephems except cefaclor (CCL) were < or = 0.03 microgram/mL against all strains of S. pyogenes. The MICs of cefteram (CFTM) and cefditoren (CDTR) were < or = 0.0125 microgram/mL activity against 7 strains penicillin-susceptible S. pneumoniae (PSSP). However the MIC90s of cefditoren (CDTR) was 1 microgram/mL, cefteram (CFTM), and cefcapene (CFPN) were 2 micrograms/mL against PISP and PRSP, were higher than those of other drugs, but showed slightly higher than PSSP. The MIC90s of Cephems. were 0.5-4 micrograms/mL against strains of E. coli. The MIC90s of CFTM was 0.5 microgram/mL, and CDTR, CFPN were 1 microgram/mL against E. coli were higher than those of other drugs. The four strains of E. coli however were highly-resistant which MIC90s of CCL were more than 32 micrograms/mL were obtains. Furthermore it is necessary to pay much attention to the trend of resistant such as E. coli of Cephems. Although all strains showed resistant to AMPC, MIC90 of Cephems were 0.25-1 microgram/mL, good activities against K. pneumoniae. Against beta-lactamase negative ampicillin-susceptible H. influenzae (BLNAS) 23 strains the MIC90s of CCL and other Cephems were 64 micrograms/mL and 0.25-8 micrograms/mL. The MIC90s of CDTR and CFTM were < or = 1 microgram/mL of BLNAR (15 strains). However there of CFDN and CPDX were 8 micrograms/mL and CCL were > or = 16 micrograms/mL. Two strains which were produced beta-lactamase were highly--ABPC resistant. Although B. catarrhalis all strains were produced beta-lactamase and Cephems except for CCL showed better susceptibility than AMPC. The MIC90s of Cephems were 0.25-2 micrograms/mL against Peptostreptococcus spp.

Administration, Oral↗

PubMed1986

In vitro and in vivo evaluation of A-56268 (TE-031), a new macrolide.

The in vitro and in vivo antibacterial activity of A-56268 (TE-031), the 6-O-methyl derivative of erythromycin, was compared with those of erythromycin and other reference drugs. A-56268 had the same spectrum of antibacterial activity as erythromycin. A-56268 was generally 1 log2 dilution more potent or equal to erythromycin against all organisms except haemophilus influenzae and Propionibacterium acnes, for which A-56268 was 1 log2 dilution and 3 log2 dilutions, respectively, less potent. The MBC of A-56268 and erythromycin was not significantly different from the MIC against Streptococcus pyogenes, Streptococcus pneumoniae, Staphylococcus epidermidis, and H. influenzae but was more than 2 log2 dilutions higher than the MICs for some Staphylococcus aureus strains. Human serum at a concentration of 50% did not change the in vitro potency of A-56268 or erythromycin. A-56268 was similar to erythromycin in being more active at pH 8.0 than at the physiologic pH of 7.3. The activity of A-56268 was synergistic with sulfamethoxazole against 4 of 12 strains of H. influenzae. In mouse protection tests, when administered orally A-56268 was more potent than erythromycin against H. influenzae, S. pyogenes, S. pneumoniae, and S. aureus. After subcutaneous administration the potencies of A-56268 and erythromycin were not statistically different from each other. A-56268 was more potent than erythromycin against Legionella infection in guinea pigs. The concentration of A-56268 in the serum and lung was higher than that of erythromycin after intraperitoneal administration. In A-56268 in the serum and lung was higher than that of erythromycin after intraperitoneal administration. In mice, the peak levels in serum of A-56268 and erythromycin were similar after subcutaneous administration and seven times higher for A-56268 after oral administration. The serum half-life of A-56268 was approximately twice that of erythromycin after administration by both routes.

Administration, Oral↗

PubMed1998

Use of the lactococcal nisA promoter to regulate gene expression in gram-positive bacteria: comparison of induction level and promoter strength.

We characterized the regulated activity of the lactococcal nisA promoter in strains of the gram-positive species Streptococcus pyogenes, Streptococcus agalactiae, Streptococcus pneumoniae, Enterococcus faecalis, and Bacillus subtilis. nisA promoter activity was dependent on the proteins NisR and NisK, which constitute a two-component signal transduction system that responds to the extracellular inducer nisin. The nisin sensitivity and inducer concentration required for maximal induction varied among the strains. Significant induction of the nisA promoter (10- to 60-fold induction) was obtained in all of the species studied at a nisin concentration just below the concentration at which growth is inhibited. The efficiency of the nisA promoter was compared to the efficiencies of the Spac, xylA, and lacA promoters in B. subtilis and in S. pyogenes. Because nisA promoter-driven expression is regulated in many gram-positive bacteria, we expect it to be useful for genetic studies, especially studies with pathogenic streptococci in which no other regulated promoters have been described.

Bacillus subtilis↗

PubMed1994

In-vitro evaluation of cefpodoxime.

In-vitro antimicrobial activity of cefpodoxime was evaluated against several microbial species by both conventional tests and additional parameters which take into consideration some of the conditions likely to be encountered in infected tissues. MICs for 414 recent clinical isolates, including staphylococci, streptococci, Haemophilus influenzae, Moraxella catarrhalis, several Enterobacteriaceae, Aeromonas hydrophila and Campylobacter jejuni were determined. MIC values overall were similar to those observed for strains from other geographical areas. Inhibition of growth by cefpodoxime was virtually unaffected by the inoculum size, even using bacterial populations as large as 10(9) cfu of Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, H. influenzae, beta-lactamase-negative M. catarrhalis, Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis. Growth in the presence of human serum as the only source of nutrients did not significantly affect the inhibition exerted by cefpodoxime, even against large bacterial populations of S. aureus, S. pneumoniae, E. coli, and K. pneumoniae. For K. pneumoniae, E. coli, P. mirabilis and beta-lactamase-negative M. catarrhalis it was also found that sub-MIC concentrations of cefpodoxime were still able to inhibit the majority of cells in microbial populations as large as 10(9) cfu. Evaluation of bactericidal activity demonstrated that cefpodoxime concentrations comparable to those achievable in plasma or in the respiratory tract were able to kill rapidly large bacterial populations of S. pneumoniae and S. pyogenes. The bactericidal activity was apparently lower against M. catarrhalis, H. influenzae, S. aureus, E. coli, and K. pneumoniae.

Bacteria↗

PubMed2003

[Post-marketing surveillance of antibacterial activities of cefozopran against various clinical isolates--I. Gram-positive bacteria].

As a post-marketing surveillance, the in vitro antibacterial activities of cefozopran (CZOP), an agent of cephems, against various clinical isolates were yearly evaluated and compared with those of other cephems, oxacephems, penicillins, and carbapenems. Changes in the bacterial susceptibility for CZOP were also evaluated with the resistance ratio calculated with breakpoint MIC. Sixteen species (2,363 strains) of Gram-positive bacteria were isolated from the clinical materials annually collected from 1996 to 2001, and consisted of methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), methicillin-susceptible Staphylococcus epidermidis (MSSE), methicillin-resistant Staphylococcus epidermidis (MRSE), Staphylococcus haemolyticus, Staphylococcus saprophyticus, Enterococcus faecalis, Enterococcus faecium, Enterococcus avium, Streptococcus pyogenes, Streptococcus agalactiae, penicillin-susceptible Streptococcus pneumoniae (PSSP), penicillin-intermediate resistant S. pneumoniae (PISP), penicillin-resistant S. pneumoniae (PRSP), Streptococcus milleri group and Peptostreptococcus spp. The antibacterial activity of CZOP either against MSSA or MSSE was preferable (MIC90: 2 or 0.5 micrograms/mL) and comparable to those of other cephems. CZOP was also effective on MRSE (MIC90: 16 micrograms/mL) but not on MRSA. CZOP and other cephems had low antibacterial activity against S. haemolyticus (MIC90: 64 micrograms/mL). The antibacterial activity of CZOP against S. saprophyticus was comparable to or higher than those of other cephems, but the MIC90 of CZOP in 2001 was higher than those in 1996-2000 (32 vs 1-2 micrograms/mL). The antibacterial activity of CZOP against E. faecalis was comparable to that of cefpirome (CPR; MIC90: 16 micrograms/mL) and higher than those of other cephems. No antibacterial activity of CZOP against E. faecium and E. avium was observed, like other drugs. The antibacterial activity of CZOP against S. pyogenes was as potent as those of cefotiam and CPR (MIC90: < or = 0.063 microgram/mL), and, against S. agalactiae, was also preferable (MIC90: 0.125 microgram/mL). CZOP indicated preferable antibacterial activity either against PSSP, PISP, or PRSP (MIC90: 0.25, 1, or 2 micrograms/mL). The antibacterial activity of CZOP against S. milleri group was also preferable, but the MIC90 of CZOP in 2001 was higher than those in 1996-2000 (4 vs 0.5 micrograms/mL). The antibacterial activity of CZOP against Peptostreptococcus spp. was preferable but weaker than those of cefazolin and cefmetazole. The resistance ratio estimated from breakpoint MIC of CZOP was 95.9% in MRSA, 93.5% in PRSP, 63.3% in PISP, 35.8% in S. haemolyticus, 27.9% in E. faecalis, and 13.3% MRSE. Those resistance ratios were comparable to those for cefepime (CFPM), but E. faecalis showed 91.2% for CFPM. The difference in the resistance ratio of E. faecalis demonstrated that CZOP successfully maintained its antibacterial activity against these species. In correlation of drug susceptibility, 40.3% of PRSP was not inhibited at breakpoint MIC either CZOP or CFPM while 69.2% at breakpoint MIC either CZOP or ceftazidime. In conclusion, the antibacterial activities of CZOP against the Gram-positive bacteria obtained from the 6-year duration study were consistent with the results from the studies performed until the new drug application approval. A decline in the sensitivities of S. saprophyticus, S. milleri group, PISP, and PRSP to CZOP, however, was suggested.

Carbapenems↗

PubMed1991

The effect of antimicrobial therapy on mixed infections with Bacteroides species. Is eradication of the anaerobes important?

Antimicrobial agents were used alone or in combinations in order to explore their effect on mixed aerobic-anaerobic infections. Subcutaneous abscesses were induced in mice by single and mixed infections of Bacteroides fragilis, Bacteroides melaninogenicus, Staphylococcus aureus, Streptococcus pyogenes, Streptococcus faecalis, Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa. The infected animals were treated for 5 days with spiramycin, gentamicin or metronidazole alone, or metronidazole combined with spiramycin or gentamicin. Animals were killed 5 days after inoculation and the bacterial contents of the abscesses determined. Infection induced by a single species of bacteria always responded to appropriate antimicrobial therapy. In infections caused by two species of organisms, however, therapy directed at either the Bacteroides sp. (with metronidazole) or the aerobes or facultative anaerobes (with spiramycin or gentamicin) was effective not only in significantly reducing the numbers of the target organism but also, in 13 of 24 instances, in reducing to a small extent the numbers of the other bacteria. Despite this phenomenon, in no instance did therapy with a single agent eliminate the infection and eradicate the untargeted organism. The combination of spiramycin and metronidazole increased the reduction in numbers of B. melaninogenicus in single-organism infections and of Bacteroides sp. in mixed infections with S. aureus and S. pyogenes. These findings support the need to aim treatment at all components of mixed infections.

Abscess↗

PubMedDate not supplied

Antimicrobial activity in vitro of cefaclor, a new oral cephalosporin.

The antimicrobial activity of cefaclor, a new orally administered cephalosporin derivative, was studied in vitro against a variety of Gram-positive and Gram-negative clinical isolates. Both penicillin-resistant and penicillin-susceptible strains of Staphylococcus aureus were susceptible to cefaclor, with mean MICs of 1.44 and 0.93 microgram/ml, respectively. However, the MBC for penicillin-resistant S. aureus was higher than that for the penicillin-susceptible strains. All strains of Streptococcus pyogenes, Streptococcus viridans, and Streptococcus pneumoniae tested were highly susceptible to cefaclor; all strains of Streptococcus faecalis were highly resistant to cefaclor. Strains of Escherichia coli, Klebsiella sp., Proteus mirabilis, and Hemophilus influenzae were susceptible to cefaclor. Eighty per cent of strains of H. influenzae were inhibited by 5 micrograms/ml of cefaclor. Most strains of Enterobacter sp., indole-positive Proteus, Pseudomonas sp., and Serratia sp. were resistant to cefaclor.

Bacteria↗

PubMedDate not supplied

In vitro activity of flomoxef in comparison to other cephalosporins.

Flomoxef and cefazolin had nearly the same activity against staphylococci, which was stronger than that of other cephalosporins. Against Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus pneumoniae, cefotaxime and cefazolin were more active than flomoxef, but the other cephamycins were less active than flomoxef. In comparison to the other cephalosporins, latamoxef and flomoxef had higher activity against Branhamella catarrhalis, whereas cefotaxime, latamoxef and cefotetan were more active against Haemophilus influenzae. Flomoxef was the only drug exhibiting activity against Clostridium difficile. The activity of flomoxef and latamoxef against Bacteroides fragilis was stronger than that of the other cephalosporins, but Bacteroides bivius was resistant to each of these antibiotics.

Bacteria, Anaerobic↗

PubMedDate not supplied

In vitro activity of cefpodoxime in comparison with other oral beta-lactam antibiotics.

The aim of our study was to re-evaluate the in vitro activity of cefpodoxime in comparison with other oral beta-lactam antibiotics against bacteria causing respiratory tract infections. The study drugs were cefpodoxime, cefaclor, cefixime, cefuroxime, cefetamet, cefprozil, and the combination of amoxicillin and clavulanic acid (= augmentin). In addition, cefotaxime as the standard agent of parenteral third generation cephalosporins was examined. The organisms tested were Staphylococcus aureus, Streptococcus pyogenes, Streptococcus agalactiae, streptococci of serogroups C and G, Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Proteus mirabilis. Minimal inhibitory concentrations of the antimicrobials were determined with the agar dilution procedure. Cefpodoxime showed the broadest spectrum and generally also the highest activity of the oral beta-lactam antibiotics examined. The drug was equally active against the major groups of beta-lactamase negative and positive bacteria causing respiratory tract infections. Against penicillin-resistant pneumococci, all beta-lactam agents exhibited reduced activity comparable to the reduced activity of penicillin.

Bacteria↗

PubMed1992

Comparative in vitro activity and beta-lactamase stability of RU29246, the active metabolite of HR916B.

HR 916B is a new orally absorbed cephalosporin. In tests its active metabolite, RU29246, inhibited Streptococcus pyogenes, Streptococcus agalactiae and Streptococcus pneumoniae at less than or equal to 0.12 micrograms/ml, which is similar to the antibacterial activity of cefuroxime, and was more active than cefaclor. It was also more active (MIC 2 micrograms/ml) than cefixime, cefuroxime, cefaclor and cefotaxime against staphylococci. RU29246 inhibited Escherichia coli, Klebsiella pneumoniae, Citrobacter diversus, Klebsiella oxytoca, Proteus mirabilis, Providencia stuartii and Salmonella spp. at less than or equal to 1 microgram/ml, thus being more active than cefuroxime and cefaclor, but was less active than cefixime and cefotaxime. It did not inhibit Pseudomonas aeruginosa and other Pseudomonas spp., Enterobacter spp., Serratia marcescens or Bacteroides fragilis. RU29246 was not hydrolyzed by TEM-1, Staphylococcus aureus TEM-2 or Moraxella catarrhalis beta-lactamases, but was hydrolyzed by TEM-3 and the chromosomal beta-lactamases of Proteus vulgaris and Morganella morganii. Plasmid and chromosomal beta-lactamases were inhibited by RU29246.

Cephalosporins↗

PubMed1992

In vitro activity of the new glycopeptide decaplanin.

The activity of decaplanin, a new glycopeptide, was compared to that of vancomycin, teicoplanin and daptomycin. Decaplanin was two- to four-fold less active than vancomycin, telcoplanin and daptomycin against Staphylococcus aureus and Staphylococcus epidermidis, with an MIC90 of 2 micrograms/ml for methicillin-susceptible and 4 micrograms/ml for methicillin-resistant isolates. Decaplanin had activity similar to that of vancomycin against Streptococcus pyogenes, Streptococcus agalactiae, group C and G streptococci, with an MIC90 of 0.12 micrograms/ml. It was less active than the other agents against the viridans group streptococci (MIC90 4 micrograms/ml). The activity of decaplanin against enterococci (MIC90 4 micrograms/ml) was similar to that of vancomycin. Clostridium spp. were inhibited by 0.5 micrograms/ml, peptostreptococci and peptococci by 0.25 microgram/ml. Decaplanin was active from pH 5.5 to 7.5. Inoculum size had a minimal effect on MICs, and increased concentrations of Ca2+ and Mg2+ and 50% serum did not alter MICs or MBCs.

Anti-Bacterial Agents↗