Biomedical subjects

K Deguchi

Publications and source records attributed to K Deguchi.

At least 199 records · Page 11Linked to original sources

PubMed1992

[Antibacterial activity of rokitamycin against fresh clinical isolates].

We obtained bacterial strains which were clinically isolated and identified from outpatients with various infections in medical institutions throughout Japan. Possible antibacterial activities of rokitamycin (RKM) were examined against these isolates. Minimum inhibitory concentrations (MICs) were determined through a comparative study with reference drugs. The results of the study are summarized as follows. 1. Resistance patterns of 400 isolates which were highly resistant to macrolides (MLs) with MIC values > 100 micrograms/ml were classified into 55 patterns. Staphylococcus spp. showed cross resistance to 14-membered ring MLs with 100% cross resistance observed between erythromycin (EM) and clarithromycin (CAM), and 85.2% between EM and oleandomycin (OL). Fewer isolates showed strong resistance to 16-membered ring MLs than to 14-membered ring MLs. Cross resistances observed among the Staphylococcus isolates were 100% between acetylmidecamycin (MDM-AC) and kitasamycin (leucomycin (LM)), 93.9% between MDM-AC and josamycin (JM), and 53.3% between MDM-AC and RKM. Streptococcus spp. and Peptococcus spp. showed very similar resistance patterns to both 14- and 16-membered ring MLs, but resistance patterns to RKM were quite different. Most of anaerobic streptococci and Bacteroides fragilis group had similar resistance patterns to 14- and 16-membered ring MLs, but in some cases a pattern similar to that of Staphylococcus spp. was observed. 2. When ML-resistant bacteria isolated during 1975 to 1980 were compared to those isolated in 1986 and 1989, it was observed that resistance of Staphylococcus aureus remained almost unchanged, that of Streptococcus pyogenes was lower in the later years than during 1975 to 1980, but that of Streptococcus pneumoniae increased. 3. Most of ML-resistances of the resistant isolates were inducible, but extents of induction varied depending on drugs tested. Strong inductions were observed when 14-membered ring MLs were used, but inductions were minimal with 16-membered ring MLs. RKM appeared to induce resistance to the least extent. From these results, it appears that the RKM is quite useful clinically even in the 1990s.

Bacterial Infections↗

PubMed1992

[The changes in molecular markers for hemostatic activation after t-PA therapy in case of pulmonary embolism].

We observed the changes of molecular markers for hemostatic activation in a patient with acute pulmonary embolism treated with 2 x 10(7) unit tissue plasminogen activator (t-PA). Blood samples were obtained before, just after, at 30 min, 1, 2, 6, and 24 hours after the infusion. Molecular markers included thrombin-antithrombin III complex (TAT), plasminogen-alpha 2 plasmin inhibitor complex (PIC), and thrombomodulin (TM). Marked elevation of TAT was observed from immediately after the t-PA infusion to 6 hours after, although it had been observed for only 1 hour in our previous report on the cases of acute myocardial infarction. PIC level was significantly increased during t-PA infusion but returned to almost baseline value 6 hours after the end of t-PA infusion. This finding was almost the same as the one previously reported concerning acute myocardial infarction cases. TM level increased throughout the evaluation, and remained so, even on the 7th day after t-PA infusion. Our present data revealed a clear difference between the reactive TAT increases after t-PA therapy in acute myocardial infarction cases and in acute pulmonary embolism cases. Our present data also revealed a prolonged elevation of TM during the acute period of pulmonary embolism. It is therefore necessary to keep an eye on the changes of molecular markers for hemostatic activation after t-PA therapy in acute pulmonary embolism.

Aged↗

PubMed1992

[Combined effects of arbekacin with other antibiotics against methicillin-resistant Staphylococcus aureus. I. The combined effect of arbekacin with fosfomycin or clavulanic acid/ticarcillin].

As arbekacin (ABK) has a highly potent antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA), its combined effects with fosfomycin (FOM) and clavulanic acid/ticarcillin (CVA/TIPC) against MRSA were examined. The obtained results are summarized as follows. 1. Against MRSA either combination, FOM+ABK or CVA/TIPC+ABK showed a strong antibacterial effect at the MIC or the sub MIC of ABK in the blood expected from clinical observations. The MIC of ABK by the combination use seemed to be equivalent to the MBC value. 2. Effective concentrations of antibiotics in these combinations appeared to be strongly dependent on the effective concentration of ABK and less dependent on that of FOM or CVA/TIPC. Therefore, the antibacterial activity of a combination seems to mostly depend on the antibacterial activity and the concentration of ABK. 3. As FOM and CVA/TIPC have antibacterial activities against Pseudomonas aeruginosa, combinations of ABK with these antibiotics are likely to be effective against double infection with P. aeruginosa in MRSA infected patients.

Aminoglycosides↗

PubMed1992

[Combined effects of arbekacin with other antibiotics against methicillin-resistant Staphylococcus aureus. II. The combined effect of arbekacin with imipenem or cefminox].

Combined antibacterial effects of imipenem (IPM)+arbekacin (ABK) and cefminox (CMNX)+ABK against methicillin-resistant Staphylococcus aureus (MRSA) were examined and the obtained results are summarized below. 1. Either combination, IPM+ABK or CMNX+ABK, showed a strong antibacterial effect against MRSA when blood concentration of ABK were sustained at MIC as could be expected in clinical situations. While at sub MICs of ABK the antibacterial effect of these combination was slightly less than those of the previously reported combinations of ABK and other antibiotics. 2. Antibacterial effects of the combinations against MRSA were strongly dependent on the concentration of ABK and less dependent on the concentration of IPM or CMNX. As were observed in the previously tested combinations of ABK with other antibiotics, the antibacterial effect of the combination appeared to be highly dependent on the antibacterial activity and the concentration of ABK. 3. As IPM has potent antibacterial activities against Gram-negative bacteria (GNB) including Pseudomonas aeruginosa while CMNX has potent antibacterial activities against GNB except P. aeruginosa, it is likely that the combinations of IPM+ABK or CMNX+ABK are useful for treatment of infections with MRSA together with GNB.

Aminoglycosides↗

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

[Induction therapy of acute promyelocytic leukemia with all-trans retinoic acid: a case, followed by conventional post-remission chemotherapy in complete remission].

A 41-year-old man with untreated acute promyelocytic leukemia (APL) was treated with all-trans retinoic acid (ATRA) 80mg/body/day per os. Complete remission was reached in 16 day without bone marrow hypoplasia and aggravated disseminated intravascular coagulation. The chromosomal abnormality, t (15;17), which presented before therapy has not been found since the 29th day of therapy. During the course of induction therapy with ATRA, there was no complication worth of mentioning. Induction therapy with ATRA is thought to be more effective and safer than conventional chemotherapy to attain complete remission in APL. The complete remission has been maintained for 11 months with conventional postremission chemotherapy.

Adult↗

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↗