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T Kamimura

Publications and source records attributed to T Kamimura.

At least 181 records · Page 10Linked to original sources

Inhibitory effect of Pseudomonas aeruginosa on phagocytosis and killing of rabbit polymorphonuclear leukocytes.

Polymorphonuclear leukocyte (PMN)-resistant strains of Pseudomonas aeruginosa had the ability to interfere with phagocytosis of Escherichia coli, whereas PMN-sensitive strains of P. aeruginosa did not. When mice were infected with an ordinarily nonpathogenic strain of E. coli, addition of a PMN-resistant strain of P. aeruginosa gave a mortality considerably higher than that obtained with P. aeruginosa alone, whereas addition of a PMN-sensitive strain of P. aeruginosa gave a mortality not different from that observed with P. aeruginosa alone. This increased mortality in mixed infection with E. coli and PMN-resistant P. aeruginosa was obtained by facilitation of tissue invasion by both bacteria from the inoculum site.

Animals↗

In vitro and in vivo antibacterial activities of FR-31564, a new phosphonic acid antibiotic.

FR-31564, a new phosphonic acid antibiotic, was active against most Gram-negative bacteria except Serratia marcescens and glucose-nonfermenting Gram-negative rods excluding Pseudomonas aeruginosa. The antibacterial activity in vitro of FR-31564 was stronger than that of fosfomycin especially against Escherichia coli, Klebsiella pneumoniae, Enterobacter species and P. aeruginosa. FR-31564 also was active against Gram-negative bacteria resistant to beta-lactam antibiotics and against gentamicin-resistant strains of P. aeruginosa. The antibacterial activity in vitro of FR-31564, like that of fosfomycin, was enhanced when 10% rabbit blood was added to the nutrient agar. The therapeutic efficacy of FR-31564 in experimental infections in mice was superior to that of fosfomycin in infections due to most Gram-negative bacteria used, and was similar to that of gentamicin in infections due to Citrobacter freundii, Proteus rettgeri and Proteus inconstans B. The protective effect of FR-31564, particularly in the P. aeruginosa infection, was superior to that of other control drugs including gentamicin.

Animals↗

Laboratory evaluation of ceftizoxime, a new parenteral cephalosporin.

(6,7R)-7-[(Z)-2-(2-Amino-4-thiazoyl)-2-methoxyiminoacetamido]-8-oxo-5-thia-1 -azabicyclo[4,2,0]oct-2-ene-2-carboxylate (ceftizoxime), a new parenteral cephalosporin, in more potently active in vitro and in vivo against various gram-negative bacilli including the opportunistic pathogens such as Enterobacter, Citrobacter species and Serratia marcescens than cephalosporins and cephamycins recently developed. Ceftizoxime is extremely stable to various types of beta-lactamases, and has a high ability to penetrate the outer membrane of gram-negative organisms.

Animals↗

Ceftizoxime (FK 749), a new parenteral cephalosporin: in vitro and in vivo antibacterial activities.

FK 749 is a new parenteral cephalosporin derivative which is more active against various gram-negative bacilli, including the opportunistic pathogens such as Enterobacter, Citrobacter species, and Serratia marcescens, than cephalosporins and cephamycins such as cefotiam, cefamandole, cefuroxime, cefotaxime, and cefmetazole. FK 749 was especially active against gram-negative organisms resistant to these related antibiotics. FK 749 was more potent in bactericidal activity than the other antibiotics, and the activity was clearly enhanced in the presence of 90% defibrinated rabbit blood. The therapeutic effect of subcutaneously injected FK 749 in mice infected with various gram-negative bacilli was far superior to that of cefotiam, cefamandole, cefuroxime, and cefmetazole and was almost the same as that of cefmetazole in mice infected with Staphylococcus aureus and that of ticarcillin in mice infected with Pseudomonas aeruginosa. FK 749 has, in general, nearly the same in vitro and in vivo antibacterial activities as cefotaxime. The former had more potent bactericidal activity in the presence of the blood than the latter and showed more excellent therapeutic effect than cefotaxime against infections caused by large inoculum sizes.

Animals↗

Comparison of antibacterial activity of a new cephalosporin, ceftizoxime (FK 749) with other cephalosporin antibiotics.

FK 749 is a distinctive new parenteral cephalosporin antibiotic with a broad antibacterial spectrum which is more potently active against a wide variety of Gram-negative bacilli, including the opportunistic pathogens such as Citrobacter and Enterobacter species and Serratia marcescens, than SCE 963, T 1551 and cefmetazole. The activity of FK 749 against Escherichia coli, Klebsiella pneumoniae, pyogenes was by far superior to that of the three other antibiotics. These test organisms were not resistant to FK 749. The antibacterial activity of FK 749 against Pseudomonas aeruginosa was almost the same as that of ticarcillin but was inferior to that of gentamicin and T 1551. The bactericidal activity of FK 749 against E. coli, K. pneumoniae and Proteus mirabilis was more potent than that of the three other antibiotics. FK 749, like cefmetazole, was extremely stable to beta-lactamases. In studies in mice, the therapeutic effect of subcutaneous injection of FK 749 against various infections due to Gram-negative bacilli was by far superior to that of SCE 963, T 1551 and cefmetazole, was almost the same as that of SCE 963 and cefmetazole against Staphylococcus aureus infection and that of ticarcillin against P. aeruginosa infection.

Ampicillin↗

Bactericidal activity of cephalosporins in an in vitro model simulating serum levels.

The bactericidal activity of cefazolin, cephaloridine, and cephalothin in a simulated intramuscular study (500 mg) and a simulated intravenous drip infusion study (2 g/2 h) is reported. In both model systems, the bactericidal activity of cefazolin surpassed that of cephalothin, and there were certain differences between cefazolin and cephaloridine in the simulated intramuscular study when human serum was used as a medium. In a routine reference static system, the drug levels were constant at the simulated peak level of each cephalosporin by both routes. In this system the three cephalosporins were equal in activity. In a third experiment, the effect of drug concentrations and exposure time on bactericidal activity of the cephalosporins was studied. The bactericidal activity of cephaloridine was the strongest of the three drugs when exposure time was 2 h and drug concentration was less than four times the minimal inhibitory concentration. At concentrations above four times the minimum inhibitory concentration, all three cephalosporins were equal in activity when the exposure time was 2 h.

Bacteria↗

Differential susceptibility of indole-positive and -negative strains of Klebsiella pneumoniae to cefazolin, choramphenicol and tetracycline.

Biochemical properties and antibiotic susceptibilities of 168 clinical isolates of Klebsiella pneumoniae were tested. On the basis of the indole reaction, 30 isolates (18%) were indole-positive and 138 isolates (82%) were indole-negative. A significant difference in antibiotic susceptibility was found in each of the two groups of isolates. Of the indole-negative isolates, 82.6% were susceptible to cefazolin at 6.25 microgram/ml or lower, while the indole-positive isolates varied in susceptibility to cefazolin. All of the indole-positive isolates were susceptible to chloramphenicol and tetracycline, but the indole-negative isolates varied in their susceptibility to these antibiotics. Whereas there was no relationship between indole production and susceptibility to cephalothin among the K. pneumoniae isolates studied, it appeared that there was a correlation between the indole reaction and susceptibility to cefazolin, chloramphenicol and tetracycline.

Cefazolin↗

Laboratory evaluation of FR10024 a new cephalosporin derivative.

FR10024 is a broad-spectrum antibiotic. The in vitro antibacterial activity of FR10024 against clinical isolates of Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis is greater than that of any of the cephalosporins developed to date. Indole-positive Proteus, Enterobacter, and Citrobacter are resistant to FR10024, as is true for the other cephalosporins. However, more than half of the strains of Enterobacter and Citrobacter tested were susceptible to FR10024 at an inoculum of 10(6) cells/ml. A single subcutaneous injection of FR10024 to mice with peritoneal infections due to S. aureus and several species of gram-negative bacilli gave a protective effect inferior to that of cefazolin but appeared to be superior to that of cephalothin. When given in two divided doses, however, the protective effect of FR10024 was enhanced and almost equaled that of cefazolin. The serum levels and rates of urinary recovery of FR10024 varied in different animal species. The mean peak serum level of FR10024 in humans after a single intramuscular injection of 500 mg was two times higher than that of cephalothin. The serum half-life after intramuscular injections of 250 and 500 mg was slightly shorter than that of cephalothin. After receiving 250 mg of FR10024 intramuscularly the urinary recovery rate was 87.7% in healthy volunteers. The biliary excretion rate of FR10024 was particularly high. The 24-h excretion of FR10024 in rats was 63.3%, this being six to seven times higher than that for cefazolin, which has the highest biliary excretion of the other known cephalosporins. When FR10024 was injected intramuscularly (20 mg/kg), it was found that the hepatic levels of FR10024 in rats were the highest of all the cephalosporins, including cefazolin, but the levels of FR10024 in other tissues were not as high as those of cefazolin.

Adult↗

In vitro and in vivo evaluation of ceftezole, a new cephalosporin derivative.

Ceftezole, a new cephalosporin derivative, was compared with cefazolin, cephaloridine, and cephalothin. Data obtained indicate that it is a broad-spectrum antibiotic, with almost identical antimicrobial activity against pathogenic organisms isolated from patients. The therapeutic effect of ceftezole on experimental infections in mice was similar to that of cefazolin and was superior to that of cephalothin. The binding of ceftezole to serum proteins was somewhat less than that of cefazolin. The concentrations of ceftezole in the sera of test animals and human volunteers were determined after intramuscular injection of 20 mg/kg and after a single dose of 500 mg, respectively. The concentration of ceftezole in the serum of volunteers peaked at 24.9 mug/ml 15 min after injection and remained effective (about 2.6 mug/ml) at 4 h. The half-life in serum under the same conditions was 56 min, i.e., about one-half that of cefazolin. The 24-h urinary recovery rate was 87.5%. Most of the administered ceftezole was excreted unchanged mainly through the urinary tract. The biliary excretion rate in SD strain rats after intramuscular injection of 20 mg/kg was about 4.4%. As compared with commercially available cephalosporins, ceftezole was second only to cefazolin in biliary excretion rate. Various tissue levels of ceftezole in animals were higher than cephalothin but, with the exception of renal levels in the early stage after administration, were lower than cefazolin.

Adult↗

Laboratory evaluation of FR10612, a new oral cephalosporin derivative.

FR10612, like cephalexin, is a broad-spectrum oral cephalosporin derivative. The antimicrobial activity of FR10612 against clinical isolates was similar to cephalexin; however, at a low inoculum size its activity was greater than cephalexin against Klebsiella pneumonia and Proteus mirabilis strains. Like cephalexin, the in vitro bactericidal activity of FR10612 was more influenced by the duration of contact with the test organism than by drug concentration. The bactericidal activity of FR10612 against E. coli 317 was greater than that of cephalexin in an in vitro model system which simulated the serum levels of FR10612 and cephalexin achieved in healthy volunteers after a single oral dose. The protein binding of FR10612 to human and animal serum was extremely low. FR10612 was resistant to beta-lactamases from gram-negative bacilli. It showed resistance similar to cephalexin, but was more resistant to beta-lactamases than were cephaloridine, cephalothin and cefazolin. The protective effect of FR10612 in mice infected with various pathogens was greater than cephalexin. The serum levels of FR10612 in rats were higher and more prolonged than those of cephalexin. Tissue levels of FR10612 in rats also persisted for a long time period reflecting the serum levels. In healthy volunteers, rabbits and monkeys the serum levels of FR10612 were initially lower than those of cephalexin but persisted for a longer time period. The total 24-hour urinary excretion of FR10612 in healthy volunteers after oral administration was almost the same as that of cephalexin, but the excretion rate of FR10612 was slower, and the urinary levels were more persistent than those of cephalexin.

Animals↗

Antitrichophyton activity and dermal tissue concentration of pyrrolnitrin.

Though pyrrolnitrin is surpassed by clotrimazole in in vitro antitrichophyton activity against Trichophyton sp., the therapeutic effect of pyrrolnitrin against experimental trichophytosis in guinea pigs was more potent than that of clotrimazole. The detection of antifungal activity from topically treated guinea pigs suggests that pyrrolnitrin obtains higher concentrations than clotrimazole in dermal tissue.

Animals↗