Biomedical subjects

R Ishihara

Publications and source records attributed to R Ishihara.

At least 109 records · Page 6Linked to original sources

PubMed1992

[Antimicrobial activities of major oral antibacterial agents against clinically isolated microbial strains from inpatients].

Antimicrobial activities were examined for major antibacterial agents against clinically isolated microbial strains which were isolated and identified from materials collected from inpatients with various infections in 1988, 1989 and 1990, and the following conclusions were obtained. 1. Among strains isolated each year, methicillin-resistant Staphylococcus aureus (MRSA) were found frequently. 2. CEPs-resistant Escherichia coli strains were observed among strains isolated each year. 3. Increasing tendencies in resistances of Citrobacter freundii, Enterobacter spp., Serratia marcescens to cephems and new quinolones were observed. 4. Increasing tendencies in resistances of Proteus vulgaris to ceftazidime (CAZ) and new quinolones appeared to exist. 5. Among strains isolated each year, resistances of Pseudomonas aeruginosa to CAZ and quinolones were observed in high rates, but also their resistances to imipenem appeared to increase. 6. Many of recently increasing multiple resistant bacteria seem to have different sites of drug action and/or to have non-hydrolytic modes of resistance.

Anti-Bacterial Agents↗

PubMed1992

[Antimicrobial activities of major oral antibacterial agents against clinically isolated microbial strains from outpatients with respiratory tract infection].

Minimum inhibitory concentrations (MICs) were determined for major oral antibacterial agents for clinically isolated microbial strains from materials collected from outpatients with respiratory tract infections in 1988, 1989 and 1990, and the following conclusions were obtained. 1. Methicillin-resistant Staphylococcus aureus (MRSA) appeared to be responsible for community-acquired respiratory tract infections, but there also was a tendency showing that MRSA increased year by year. 2. A tendency was observed indicating that benzylpenicillin (PCG)-insensitive Streptococcus pneumoniae (PISP) increased year by year. 3. Beta-lactamase-producing strains of Haemophilus influenzae were observed in a certain ratio, and also those of Branhamella catarrhalis were found in high ratios. 4. A tendency of increasing resistance of Klebsiella pneumoniae to new quinolones was observed. 5. It is of a great importance to evaluate methods of selecting primary choice antibiotic agents since increasing numbers of new oral antibacterial agents are becoming rapidly available.

Anti-Bacterial Agents↗

PubMed1992

[Antibacterial activities of sisomicin against fresh clinical isolates].

To investigate antibacterial activities of sisomicin (SISO), MICs of SISO as well as other aminoglycosides (AGs) were determined against many clinical isolates which were obtained in 1991. Results are summarized below: 1. No SISO-resistant strains were observed among isolates of Escherichia coli, Citrobacter diversus, Klebsiella pneumoniae, Klebsiella oxytoca, Enterobacter aerogenes, Proteus mirabilis and Morganella morganii. 2. In comparison with the results of our previous study against isolates obtained in 1986, the rate of methicillin-resistant Staphylococcus aureus (MRSA) was higher, and SISO-resistant strains were observed at a high rate among the MRSA. Also, SISO-resistant strains of Serratia marcescens increased. However, the rate of SISO-resistant strains of Pseudomonas aeruginosa decreased, and among Citrobacter freundii, Enterobacter cloacae and Proteus vulgaris, SISO-resistant strains did not increase over the years. 3. MICs of SISO against Providencia rettgeri and Providencia stuartii were high, suggesting that antibacterial activities of SISO was weak against genus Providencia. 4. For comparison, according to MICs of ofloxacin and imipenem, new quinolone-resistant strains were observed at a high rate among various organisms, and carbapenem-resistant strains were observed at a high rate among S. marcescens and P. aeruginosa. 5. SISO is still one of the useful AGs in the 1990's since it maintains its strong antibacterial activities against most clinical isolates obtained in recent years and its potential as a combination drug with beta-lactams is being reported.

Bacteria↗

PubMed1992

[Combined effects of arbekacin with other antibiotics against methicillin-resistant Staphylococcus aureus. III. Combined effects of arbekacin with cefotiam or cefuzonam].

Antibacterial effects of combination use of arbekacin (ABK) with cefotiam (CTM) or cefuzonam (CZON) were evaluated against methicillin-resistant Staphylococcus aureus (MRSA) and the following results were obtained. 1. Antibacterial effects of combinations of ABK with CTM and with CZON were equally potent against MRSA at clinically expected 1 MIC of ABK in blood. However, at a sub MIC of ABK the different effects were observed between the 2 combinations. The antibacterial effect of the former was strong and that of the latter was a little weak. 2. In either combination the potency of the antibacterial activity was less dependent on the concentration of CTM or CZON, but was strongly dependent on ABK concentrations. These results suggest that antibacterial effects of the combinations were highly dependent on antibacterial potency and concentration of ABK as previously reported for combinations of ABK with other drugs. 3. The combination use of ABK with CTM appears to be useful in cases of infection by MRSA alone while the combination use of ABK with CZON appears to be useful in cases of double infection with MRSA and Gram-negative bacterium.

Aminoglycosides↗

PubMed1992

[Combined effects of arbekacin with other antibiotics against methicillin-resistant Staphylococcus aureus. IV. Combined effects of arbekacin with cefmetazole or flomoxef].

Antibacterial effects of combination use of arbekacin (ABK) with cefmetazole (CMZ) or flomoxef (FMOX) were evaluated against methicillin-resistant Staphylococcus aureus (MRSA) and the following results were obtained. 1. Antibacterial effects of combinations of ABK with CMZ and with FMOX were equally potent against MRSA at clinically expected 1 MIC of ABK in blood. However, at a sub MIC of ABK different effects were observed between the 2 combinations. The former combination was slightly less effective than the latter. 2. In either combination the potency of the antibacterial activity was less dependent on the concentration of CMZ or FMOX, but was strongly dependent on ABK concentrations. These results suggest that antibacterial effects of the combinations were highly dependent on antibacterial potency and concentration of ABK as previously reported for combinations of ABK with other drugs. 3. It appears that the antibacterial activity of the combination of the sub MIC of ABK with a beta-lactam is an important point in considering the effectiveness of a combination therapy.

Aminoglycosides↗

PubMed1992

[Bacteriological evaluation of ofloxacin otic solution].

Clinical trials of ofloxacin (OFLX) otic solution, such as an early phase II study, a dose-finding study, a phase III double-blind comparative study and open studies, were conducted in the period from February 1988 to October 1989. In these studies, organisms were isolated from secretions of middle ear in patients with chronic otitis media and acute exacerbation of chronic otitis media, and from secretions of external ear in patients with external otitis. These organisms were subjected to identification, followed by determination of susceptibilities to OFLX and the other antibacterials. Results obtained are summarized as follows: 1. In total, 746 organisms were defined as the presumable causative organisms in 439 patients with otitis media and 80 with external otitis. Among the isolates, aerobic Gram-positive organisms were most prevalent, with an isolation rate of 66.9%, followed by aerobic Gram-negative organisms (32.4%), and obligate anaerobes (0.7%). Staphylococcus aureus and Pseudomonas aeruginosa were the organisms isolated most frequently among aerobic Gram-positive and Gram-negative bacteria, respectively. 2. The MIC90 of OFLX against the above 746 strains was 6.25 micrograms/ml. At this level, OFLX was 8 times more potent than cefmenoxime (CMX), and 32 times more potent than fosfomycin (FOM) and fradiomycin (FRM). It was postulated that OFLX retained higher local level than the MIC90 of the drug at 2 hours after topical adaptation of the otic solution, and had enough "above the MIC" and "time above MIC". 3. The MIC90 of OFLX against glucose-nonfermentative Gram-negative rods (GNF-GNR) including P. aeruginosa, which were isolated in 32.6% of the 519 patients, was superior to those of CMX, FOM, and FRM. The well-balanced antibacterial activity of OFLX was thought to be one of the properties of OFLX otic solution. 4. Previously-reported post antibiotic effect of OFLX was thought to be another property of OFLX otic solution. In conclusion, OFLX otic solution appeared to be clinically useful, because it possessed advantageous properties beyond other clinically-available otic solutions.

Bacteria↗

PubMed1992

[Antimicrobial activities of ceftazidime on fresh clinical isolates].

Antimicrobial activity of ceftazidime (CAZ) was compared with those of other cephem antibiotics against clinically isolated strains sent to us by medical institutions throughout Japan in 1989 and 1991. Those strains separated and identified from samples collected from patients with various infections were also examined, and the following results were obtained. 1. The results suggested that, compared with reports of studies conducted with clinical isolates in early 1980's, MIC90 of CAZ in 1991 were markedly higher against Staphylococcus spp., Streptococcus pneumoniae, Escherichia coli, Enterobacter spp., Serratia marcescens, Proteus vulgaris, Morganella morganii, and Pseudomonas aeruginosa. Also, among other bacteria such as Providencia rettgeri, Providencia stuartii, Xanthomonas maltophilia, and Bacteroides fragilis group, strains resistant to CAZ were observed in high proportions. However, large time-course changes were not observed in microbial activities of CAZ on Streptococcus pyogenes, Klebsiella spp, Proteus mirabilis, Pseudomonas cepacia, Acinetobacter calcoaceticus, Haemophilus influenzae and Anaerobic GPC (Gram-positive cocci). 2. Among the strains used in the study, methicillin-resistant Staphylococcus aureus (MRSA), Benzylpenicillin (PCG)-insensitive S. pneumoniae (PISP), cephamycin and oxime type cephem-resistant Gram-negative bacilli of Enterobacteriaceae and new quinolone-resistant organisms were observed in high proportions. It appears therefore, that CAZ failed to exert sufficient antimicrobial activities to these strains because of combination of resistance in these strains. 3. Antimicrobial activities of CAZ on recent clinical isolates showed problems as mentioned above. However, it was also demonstrated that CAZ maintained effective antimicrobial activities against most of the clinical isolates which could be causative organisms of infectious diseases in the clinical practice. When it is additionally taken into account that CAZ is one of those limited drugs with activity against P. aeruginosa, and it has excellent permeability through outer membrane, it is concluded that CAZ still is one of the clinically useful cephem drugs in 1990's.

Bacteria↗

PubMed1992

[Antimicrobial activity of cefetamet against clinically isolated microbial strains collected from urban RTI patients].

The authors studied antimicrobial activities of cefetamet (CFMT) and other leading oral antimicrobials of beta-lactam class against clinically isolated strains from urban respiratory tract infection (RTI) patients from January to March, 1992. 1. CFMT showed potent antimicrobial activities against "3 primary pathogens" of RTIs i.e., Streptococcus pyogenes, Streptococcus pneumoniae, and Haemophilus influenzae, but the drug had a slightly higher MIC than those of a few oxime-type cephems already on the market. 2. CFMT was as stable as cefixime to beta-lactamase, generated by Moraxella subgenus Branhamella catarrhalis, which reduces the antimicrobial activity of cephems. 3. Blood concentrations of CFMT after administering cefetamet pivoxil (CFMT-PI), an oral form of the drug, exceeded the MIC80 against the "3 primary pathogens" as well as M. (B) catarrhalis and Klebsiella pneumoniae, for a duration of approximately 9 and 11 hours, respectively, after single doses of 250 and 500 mg. This suggests that CFMT could remain above the MICs for a sufficient time period with twice daily dosages of normal dose levels. 4. It is concluded that CFMT-PI will be useful for treating urban RTIs.

Anti-Bacterial Agents↗

PubMed1992

[Synergistic action of cefodizime with other antimicrobial agents on clinically isolated microorganisms. II. Synergistic action with sisomicin].

Cefodizime (CDZM) possesses a broad antimicrobial spectrum and a relatively long half life in the blood. In addition, it shows excellent therapeutic efficacies in the treatment of infections in leukopenic animal models, hence it is expected that CDZM may have good efficacies against various infections in immunocompromised hosts. In the meantime, sisomicin (SISO) not only has strong antibacterial activities against Gram-negative rods (GNR), but has relatively low nephrotoxicity and ototoxicity. Thus, we examined antibacterial effectiveness of the combination of CDZM and SISO against clinical isolates in vitro. 1. Antibacterial effects of CDZM+SISO combination were examined using SISO susceptible strains of Escherichia coli, Citrobacter freundii, Klebsiella pneumoniae, Enterobacter cloacae, Serratia marcescens, Proteus vulgaris, Morganella morganii and Pseudomonas aeruginosa. Observations that the combination of the 2 drugs showed FIC indices between less than 0.5-less than 1.0 against most of these strains at SISO concentrations of 1 MIC or sub MIC levels strongly suggested the presence of a synergistic action between the 2 drugs against SISO susceptible strains of GNR. 2. Of the strains tested, 10% of C. freundii, 6.7% of E. cloacae, 63.3% of S. marcescens, 23.3% of P. vulgaris and 18.0% of P. aeruginosa were found to be resistant to SISO, and little synergistic effect of the 2 drugs was observed against these strains. 3. As the synergistic effect of the 2 drugs against GNR was observed against SISO susceptible strains including those which were resistant to CDZM, but not against those strains which were resistant to SISO, it seems reasonable to conclude that the appearance of the synergistic effect between the 2 drugs depends on the activity of SISO.

Cefotaxime↗

PubMed1992

[Bacteriological evaluations of combination therapies with minocycline and beta-lactams for methicillin-resistant Staphylococcus aureus. I. Cefotiam plus minocycline].

Since methicillin-resistant Staphylococcus aureus (MRSA) is resistant to multiple antibiotics, only a limited number of antibacterial agents shows efficacy against this bacteria. Therefore, combination therapy is often attempted for MRSA infections. Most of the MRSA strains recently isolated, however, have been found to show very high resistance, and some of the antibiotics which had previously been effective have been failing to produce good responses in increasing numbers of patients. Thus, the drugs used for combination therapy in MRSA infections need to be reevaluated. We assessed the bacteriological efficacy of cefotiam (CTM) plus minocycline (MINO) therapy against MRSA in an in vitro system (CTM shows relatively strong antibacterial activities against MRSA with moderate resistance, and MINO shows strong antibacterial activities against highly resistant MRSA. 1. Against MINO-susceptible MRSA strains, CTM + MINO demonstrated potent antibacterial activities at MINO concentrations of MIC or sub-MIC levels, irrespective of the MIC of CTM against MRSA strains being tested. 2. Against MINO-resistant MRSA strains (strains for which MICs of MINO exceeded the upper limit of the clinically expected plasma MINO level), CTM + MINO showed no significant antibacterial activity. These results suggested that the effect of this combination was dependent on the antibacterial activity of MINO. Therefore, the usefulness of this combination in patients with MRSA infections can be predicted based on susceptibilities of involved strains to MINO. 3. The potent antibacterial effect of this combination against MINO-susceptible MRSA strains was considered to be the result of damage to the cellular membrane by MINO and the subsequent antibiotic effect of CTM.(ABSTRACT TRUNCATED AT 250 WORDS)

Cefotiam↗

PubMed1992

[Bacteriological evaluations of combination therapies with minocycline and beta-lactams for methicillin-resistant Staphylococcus aureus. II. cefuzonam plus minocycline].

We performed an in vitro assessment of the antibacterial activity of therapy with cefuzonam (CZON) plus minocycline (MINO) against methicillin-resistant Staphylococcus aures (MRSA) infections. 1. Studies using MINO-susceptible and MINO-resistant MRSA strains suggested that the antibacterial activity of CZON + MINO was dependent on the antibiotic action of MINO, similarly to the case with cefotiam (CTM) + MINO. 2. The antibacterial activity (including the FIC index) of this combination was slightly inferior to that of CTM + MINO. However, the time course of antibacterial efficacy of CZON + MINO in MRSA pretreated with MINO was comparable to that of CTM + MINO. 3. CZON + MINO appeared to be a very useful combination in patients with mixed infections due to MRSA and Gram-negative bacteria.

Ceftizoxime↗

PubMed1992

[Synergistic action of cefodizime and other antimicrobial agents on clinically isolated microorganisms. III. Synergistic action with gentamicin].

An in vitro investigation was done on antimicrobial activities of cefodizime (CDZM) in combination with gentamicin (GM) against clinically isolated Gram-negative rods. The results are summarized as follows. 1. Combined antimicrobial activities were dependent on antimicrobial activities of GM, similar to the CDZM + sisomicin (SISO) combination. The combined activities were concentration dependent, and they were more strongly dependent on GM concentrations than on CDZM concentrations. The obtained results suggested that synergistic or cooperative antimicrobial activities of the combination would be expected when GM concentrations in blood are at or somewhat lower than 1 MIC, and clinical activities would be exerted regardless of the presence of CDZM resistant organisms, similarly to CDZM+SISO combination. 2. It seems possible that, with regard to combinations of beta-lactam antibiotics and aminoglycoside antibiotics, there exist universal rules that combined activities are dependent on activities of aminoglycoside antibiotics, and that stronger concentration dependencies on aminoglycosides would be observed than those on beta-lactams.

Bacteria↗

PubMed1992

[Synergistic action of cefodizime and other antimicrobial agents on clinically isolated microorganisms. IV. Synergistic action with dibekacin].

Antimicrobial activities of cefodizime (CDZM) in combination with dibekacin (DKB) were studied in vitro against clinically isolated Gram-negative rods. The results obtained are summarized as follows. 1. Similarly to combinations of CDZM+sisomicin (SISO) and CDZM+gentamicin (GM), combined activities of CDZM and DKB were dependent on antimicrobial activities of DKB, and the combined activities were more strongly dependent on DKB concentrations than on CDZM concentrations. The obtained results suggested that synergistic or cooperative antimicrobial activities of the combination would be expected when DKB concentrations in blood are at or somewhat lower than 1 MIC, and that clinical activities would be exerted regardless of the presence of CDZM resistant organisms, similarly to CDZM+GM combination. 2. As we have suggested previously, it seems possible that, with regard to combinations of beta-lactam antibiotics and aminoglycoside antibiotics, there exist universal rules that combined activities are dependent on activities of aminoglycoside antibiotics, and that stronger concentration dependencies on aminoglycosides would be observed than those on beta-lactams.

Bacteria↗

PubMed1992

[Antimicrobial activity of cefetamet against fresh clinical isolates of Branhamella catarrhalis].

Against strains of Branhamella catarrhalis which were separated from various RTIs (respiratory tract infections) in 1991 antimicrobial activities (MICs) of cefetamet (CFMT) were determined, and the following conclusions were obtained. 1. The MIC80 of CFMT against B. catarrhalis was 0.39 microgram/ml, which was higher than that of cefixime (CFIX) by one dilution or twofold, but was lower than that of cefpodoxime (CPDX) by two dilutions or fourfold and that of cefotiam (CTM) by three dilutions or eightfold. 2. The fact that all of the 50 strains tested were beta-lactamase producers appeared to indicate that CFMT was stable against BRO-1 and BRO-2 beta-lactamases produced by B. catarrhalis. 3. Blood concentrations of the test drug, CFMT, and control drugs upon normal single doses were calculated using pharmacokinetic parameters. Lengths of time periods during which drug concentrations stayed above their MICs against B. catarrhalis obtained in this study were determined for CFMT, CFIX, CPDX and CTM. They were, respectively, 12 hours, 12 hours, 6 hours, and 2 hours, thus CFMT appeared to remain above MIC for sufficiently long time for the treatment of RTIs which are affected by B. catarrhalis directly or indirectly.

Cefixime↗

PubMed1992

[Antimicrobial activities of ceftriaxone against clinically isolated strains].

Antibiotic activities (MICs) of ceftriaxone (CTRX) against 1,210 strains of bacteria including 28 spp. isolated in 1987 and 1990 were compared with those of other cephems. 1. When compared to data on clinically isolated strains reported in the early 1980s, strains of the following species isolated in 1990 showed extremely elevated MIC90s of CTRX: Staphylococcus spp., Streptococcus pneumoniae, Escherichia coli, Citrobacter spp., Enterobacter spp., Serratia spp., Proteus vulgaris, Morganella morganii and Providencia spp. No changes were observed in MIC90s between the 2 periods for microorganisms such as Streptococcus pyogenes, Haemophilus influenzae, Klebsiella pneumoniae, Proteus mirabilis and Peptostreptococcus spp. 2. The MIC90 of CTRX to S. pneumoniae was high because a large number of benzylpenicillin (PCG)-insensitive S. pneumoniae (PISP) was present among this species. The MIC80 to Bacteroides fragilis group was also high because highly resistant B. fragilis and B. thetaiotaomicron were isolated in large proportions among the bacteria of this group. Other oxime-type cephems also had high MICs against the above mentioned bacteria. Therefore, a further evaluation has to be made with regard to activities of oxime-type cephems such as CTRX against PISP and B. fragilis group. 3. Sample strains included, in high ratios, methicillin-resistant Staphylococcus aureus (MRSA), cephamycin-resistant as well as oxime-type cephem-resistant intestinal bacteria, Gram-negative bacteria, and new-quinolone-resistant bacteria. Some of there resistant bacteria are also CTRX-resistant, and CTRX had insufficient activities against them. 4. With regard to the assessment of changes of frequencies of specific drug-resistant bacteria, including those with CTRX-resistance from year to year, the authors would like to point out the following comment of theirs made in 1989 and 1991, which appears to be increasing its significance, "Subjects of future studies should include dose on the mechanisms for the acquisition of bacterial resistance to entire beta-lactam antibiotics and the social circumstances in which resistant bacteria appear". 5. It appears that those strains resistant to cephems including CTRX are increasingly found among clinically isolated strains in recent years. CTRX, however, was found still effective against most clinical pathogens. Furthermore, considering that CTRX is one of the few drugs which sustain high blood concentrations of active forms we concluded that CTRX is a useful cephem-group antibiotic.

Bacteria↗

PubMed1991

Immunohistochemical study of tyrosine-hydroxylase-positive cells and fibers in the chicken spinal cord.

Tyrosine hydroxylase (TH)-positive cells and fibers were examined by immunohistochemistry in the chick spinal cord. TH-positive cells, which were located in laminae I, V and X, were most frequently found in the rostral part of the cervical spinal cord, with fewer cells being found in more caudal levels of the spinal cord. TH-positive cells located in lamina X, which were bipolar in shape, were mainly found in regions lateral as well as just ventral to the central canal. They had processes reaching to the central canal. The terminals of these cerebrospinal-fluid-contacting cells were oval in shape, and were most frequently found at the ventral wall of the central canal. There were dense clusters of TH-positive fibers in lamina X. A meshwork-like structure of TH-positive fibers was found over the lateral wall of the central canal. A high density of TH-positive fibers was also found in the medial part of laminae V-VII. In lamina IX, small numbers of TH-positive fibers were observed in the lateral motor column of the brachial spinal cord, and in the medial and lateral motor columns of the lumbosacral spinal cord. However, within the medial motor column of the brachial spinal cord TH-positive fibers were densely distributed around somal as well as dendritic profiles. Similar to our previous observations on serotoninergic fibers. TH-positive fibers were also differentially distributed in the ventral horn of the chicken spinal cord: a high density of TH-positive fibers was localized to specific regions of the spinal motor nucleus.

Animals↗

PubMed1991

[Biological types and drug-sensitivities of multiple strains of freshly isolated methicillin-resistant Staphylococcus aureus].

Biological studies were done on numbers of methicillin-resistant strains of Staphylococcus aureus (MRSA) either clinically isolated at medical institutes nationwide and sent to us or isolated and identified by us from samples obtained in the year 1990 from patients with various infections. The results of the studies are summarized as follows. 1. The origins of the 1,047 strains used in our studies included arterial and venous blood samples (6.9%), samples from the respiratory tract (43.3%), surgical and dermatological samples (30.2%), otorhinolaryngological and ophthalmological samples (3.8%), urological samples (7.2%), fecal samples (5.1%) and others (3.6%), thus samples from the respiratory tract were the most frequent. 2. The strains were classified according to coagulase types into type II (76.4%), type III (2.1%), type IV (15.4%), type VII (5.3%) and other types (0.8%), thus type II strains were the most numerous. When classified according to their origins, type II strains were found in a significantly high frequency in respiratory tract samples, and type IV strains appeared to be present at relatively high frequencies in the surgical, dermatological, otorhinolaryngological and ophthalmological samples. Some coagulase types were found more frequently in samples from some institutes than in others, but coagulase type distributions were similar in different localities. 3. The strains were classified according to their enterotoxin types into type A (22.8%), type B (10.5%), type C (54.9%) and other types (11.7%), thus type C strains were the most frequent. Significant correlations were observed between enterotoxin type C and coagulase type II, and type A and type IV. 4. Defining strains with minimum inhibitory concentrations (MICs) of greater than or equal to 100 micrograms/ml as high MRSA and less than or equal to 50 micrograms/ml as moderate MRSA, 94.8% of coagulase type II strains were high MRSA and 78.9% of coagulase type IV strains were moderate MRSA, thus coagulase type II strains tended to be high in methicillin resistance. 5. MIC50 and MIC90 of vancomycin (VCM) against many of these strains of MRSA were 0.78 and 1.56 micrograms/ml, respectively, suggesting that VCM has also a potent antibacterial activity against recent isolates of MRSA in Japan.

Cefamandole↗

PubMed1991

[Synergistic action of cefodizime and other antimicrobial agents on clinically isolated microorganisms. I. Synergistic action with minocycline].

Since cefodizime (CDZM) shows a broad antimicrobial spectrum and relatively long half life in blood, we examined its synergistic action with minocycline (MINO) in vitro against Staphylococcus aureus. 1. CDZM in the presence of MINO, most of cases 1 MIC showed FIC index greater than 0.5-less than or equal to 2 against methicillin-susceptible S. aureus (MSSA), thus the results suggested a synergistic action against S. aureus. 2. CDZM in combination with MINO at 1 MIC or sub MIC where therapeutically a favorable efficacy is expected on MINO-susceptible strains exhibited FIC index less than or equal to 0.5-less than or equal to 1, Methicillin-resistant S. aureus (MRSA), thus suggesting a synergistic action against MINO-susceptible MRSA strains. Synergism was hardly recognized against MINO-resistant MRSA strains, however. 3. Synergism by both drugs was produced in MINO-susceptible strains of S. aureus including MRSA where MIC by CDZM was high or moderate, but no synergism was demonstrated against MINO-resistant strains. That is, synergistic action by both drugs was thought to depend on antimicrobial activity of MINO.

Cefotaxime↗