The mode of antifungal action of a thiocarbamate antimycotic tolnaftate and a related compound naphtiomate-N was studied using yeast-phase cells of a relatively sensitive fungus S. schenckii as the test organism. The results are summarized as follow:
(1) As monitored by optical density, dry weight and viable counts of fungal cultures, the extent of growth inhibition by tolnaftate and naphtiomate-N increased with increasing drug concentrations. At appreciably high drug levels, tolnaftate showed a slightfungicidal activity, while the activity of naphtiomate-N was only fungistatic.
(2) Tolnaftate and naphtiomate-N inhibited synthesis of DNA, cell wall polysaccharides and lipids to greater extents than synthesis of other cellular components in growing fungal cultures. The greatest was the inhibition by the two compounds of lipid synthesis, the extent of which appeared to be comparable to that of their growth-inhibitory activity.
(3) No evidence was obtained which showed that both compounds had any effect on the cell membrane function or the respiratory activity of S. schenckii cells.
(4) Both compounds caused no significant inhibition of in vitro activities of DNA polymerases and RNA polymerases, both of which were prepared from S. cerevisiae.
(5) Both compounds differently affected in vitro synthesis of three major classes of cell wall polysaccharides, namely chitin, mannan and β(1, 3)-glucan, by cell-free preparations from S. schenckii yeast-phase cells. The high concentrations of each compoundsubstantially inhibited the chitin synthetase activity and, to a lesser extent, the mannan synthetase activity, but they were without effect on the β(1, 3)-glucan synthetase activity. The inhibition by tolnaftate and naphtiomate-N of the chitin synthetase was of competitive type, and exhibited Ki values of 180μM and 54μM, respectively.
(6) Ergosterol synthesis in S. schenckii cells was potentlyinhibited by tolnaftate and naphtiomate-N even at concentrations lower than MIC. These compounds induced significant reduction in ergosterol content and accumulation of squalene, a biosynthetic precursor of sterol.
(7) All these results led us to the suggestion that inhibition by tolnaftate and related compound naphtiomate-N of sterol synthesis through blocking the stepof squalene epoxidation in a fungal sterol biosynthetic pathway may be primarily involved in the antifungal action of the two thiocarbamate compounds.

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The in vitro interactions of piperacillin (PIPC) and cefoperazone (CPZ) combined with 8 aminoglycosides were examined with 199 clinically isolates of 8 species of gram-positive and gram-negative strains. Those were classified into 4 types by the susceptibility against β-lactam antibiotics and aminoglycosides. The combinations of PIPC and CPZ with aminoglycosides were generally synergistic against many strains, but the synergistic activities varied with species and type. Aminoglycosides which showed the synergistic activities against many species and strains were streptomycin in combination with PIPC and tobramycin in combination with CPZ, followed by dibekacin. The organismswhich synergistically affected in many combinations were Serratia marcescens, followed by Proteus vulgaris, Enterobacter sp., Pseudomonas aeruginosa, and Staphylococcus sp. Almost no combination showed the antagonism.

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The effects of antibiotic combinations against methicillin-resistant Staphylococcus aureus (MRSA) frequently found in hospitalized patients were investigated. By means of the microtiter broth dilution checkerboard method, the combinations of VCM+MINO, VCM+RFP, VCM-FCMD, and VCM+MCIPC were synergistic against 5.9%, 0%, 84.0% and 14.4% of the strains tested. The mean fractional inhibitory concentration indices of VCM+MINO, VCM+RFP, VCM+CMD, and VCM+MCIPC were 1.50, 1.81, 0.39 and 0.78, respectively. The effect of combination of VCM+CMD was superior to those of VCM+MINO, VCM+RFP, and VCM+MCIPC. In the time-killing curve studies, the combination of VCM-FCMD also showed bactericidal effect against the selected strains of MRSA tested. This combination therapy may be useful for severe MRSA infections.

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The in vivo interaction of piperacillin (PIPC) and 4 aminoglycoside antibiotics, gentamicin (GM), dibekacin (DKB), amikacin (AMK) and tobramycin (TOB) were examined with experimental infection in mice. In experimental infection in mice with Klebsiella pneumoniae, followed by Enterobacter cloacae, Enterobacter aerogenes and Serratia marcescens, a excellent synergistic effect were observed the fixed combination of PIPC and aminoglycoside antibiotics in the ratio of 10:1. In vivo experiments using E. cloacae H-49 or E. aerogenes H-54, the combination therapy of PIPC and GM was more effective than a single therapy in reducing bacterial counts in peritoneal cavity of mice.

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The sensitivity to chemotherapeutic agents of the clinicalisolates of Staphylococcus aureus were investigated in 1982 and 1985. In this investigation, a total of 18 chemotherapeutic agents were in cluded: three penicillins, i. e., ampicillin, cloxacillin and piperacillin, six cephems, i. e., cefazolin, cefotiam, cefmetazole, ceftizoxime, cefoperazone and latamoxef, three aminoglycosides, i. e., gentamicin, dibekacin and amikacin, a tetracycline, i. e., minocycline, and others including rifampicin, vancomycin, nalidixic acid, norfloxacin and fusidic acid.
In vitro antimicrobial activities of these agents against clinical isolates of S. aureus were determined immediately after isolation by the micro broth dilution method using the Dynatech MIC 2000 system. The activities of the above agents against 24 strains isolated from the sputum in 1982 were compared with those against 17 strains isolated in 1985. As a result, it was found that the recent clinical isolates of S. aureus were less sensitive to β-lactam antibiotics, other than latamoxef, than those isolated in 1982. In contrast, no difference was found in sensitivity of clinical isolates to non-β-lactam antibiotics, such as aminoglycosides, minocycline, rifampicin and nalidixic acid, between 1982 and 1985. The incidence of cefazolin-resistant (MIC≥12.5μg/ml) strains of S. aureus increased from 12.5%(3/24 in 1982) to 23.5%(4/17 in 1985). The incidence of cloxacillin-resistant (MIC≥12.5μg/ml) strains was 17.6%(3/17) in 1985. The following agents such as cefmetazole, minocycline, rifampicin, vancomycin, norfloxacin and fusidic acid were found to be still very active against multiply resistant strains of S. aureus as compared with other agents examined.
A recent increase in incidence of the strains of S. aureus which were highly productive of glacta. mase was evident as shown by the comparison of the data in 1982 with that in 1985.
All of the strains producing β-lactamase in abundance were found to be simultaneously resistant to aminoglycoside, minocycline, rifampicin and so forth. Thus, a very close correlation was suggested between β-lactarnase producing activity and the mechanisms of resistance to non-β-lactam antibiotics that are mentioned above.

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Fundamental and clinical investigation of the synergism of minocycline and amikacin on multipleresistant staphylococcal infection was carried out. In vitro antimicrobial activity of a total of 18 chemotherapeutic agents were determined against the strain of multiple-resistant Staphylococcus aureus isolated from the aspirated sputum of the patient with lower respiratory infection. As a result, it was revealed that antimicrobial activity of minocycline, amikacin and vancomycin were more active against the strain than any other chemotherapeutic agents. Then, in vitro combined effect of minocycline and amikacin against the strain was examined. The combination was shown to be synergistic with 0.375 of the FIC index. To the patient, 100mg of minocycline was administered intravenously once a day and 100mg of amikacin intramuscularly twice a day. Clinical response to the above combination therapy was good in the case, and the strain isolated was eradicated immediately after the beginning of the therapy.
It is concluded from the above results that the combination of minocycline and amikacin is of value in the treatment of multiple-resistant staphylococcal infection.

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The effect of cefbuperazone on the phagocytosis and killing of polymorphonuclear leukocytes were studied and compared with those of cefmetazole and latamoxef. The following results were obtained.
1) Cefbuperazone showed apparently stimulative effect on the phagocytosis and killing of rabbit polymorphonuclear leukocytes against 6 strains of bacteria, and this effect was superior to those of cefmetazole and latamoxef.
2) The effect of cefbuperazone on polymorphonuclear leukocytes was activated with addition of fresh serum. A similarly phenomenon was noted with human polymorphonuclear leukocytes.
3) When Escherichia coli was pre-treated with cefbuperazone, the pre-treated cells were more easily phagocytized and killed by rabbit polymorphonuclear leukocytes than non-treated cells.
4) Nitroblue tetrazolium dye reduction in rabbit polymorphonuclear leukocytes were tested with the cells pre-treated or non-treated with cefbuperazone. The cells pre-treated with cefbuperazone increased the amount of reduced nitroblue tetrazolium in rabbit polymorphonuclear leukocytes much more than non-treated control.
From these result, cefbuperazone should show stimulative effect on the bactericidal function of polymorphonuclear leukocytes.

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Five patients were given 500mg of an antibiotic cefuroxime axetil orally, and we measured the concentrations of the drug in the peripheral and portal blood. In the three patients without dysfunction of the liver or gastrointestinal tract, the drug concentrations in both peripheral and portal blood increased as expected. In the one patient with liver dysfunction, the increase in the concentration in the peripheral blood was small. In the one patient with dysfunction of the gastrointestinal tract, the increases in the concentrations in both peripheral and portal blood were small. These results suggest that the function of the liver and gastrointestinal tract seriously affectsrthe absorption and diffusion of antibiotics taken orally. This technique was useful in measuring the concentration of the drug in both peripheral and portal blood for evaluation for drug absorption and diffusion, and such evaluation might be done of other drugs.

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A double blind comparison of ceftriaxone, a new parenteral cephalosporin and cefotaxime was carried put in the treatment of complicated urinary tract infections. Patients received 1g of either ceftria-Kone or cefotaxime twice d day for 5 days by intravenous injection. All patients were shown to have ayuria of at least 5 WBCs per high power field, bacteriuria of at least 104 bacteria per ml of urine and identifiable underlying urinary tract disease. The overall clinical efficacy of the treatment was !valuated by the criteria proposed by the UTI Committee in Japan as excellent, moderate or poor, including no response based on the combination of changes in pyuria and bacteriuria.
Of the 242 patients admitted to the study, 115 received ceftriaxone and 127 received cefotaxime. Since the significant difference was observed between 2 treatment groups in the distribution of type f infection which was classified into 6 categories according to the site of infection, presence or abence of indwelling catheter and whether the infecting organism was single or multiple. Clinical !fficacies were compared in each type of infection. There were no significant differences in the clini-!al efficacies of the two drugs in any types of infection.
As there was a difference in the number of strains isolated from the patients with indwelling:atheter between 2 treatment groups, bacteriological response to each of the two drugs was evaluated y differentiating the response in the patients with indwelling catheter from that in the patients without indwelling catheter. The overall eradication rates obtained in patients without indwelling atheters were 86.5% of 133 strains in the ceftriaxone group and 75.7% of 107 strains in the cefota-Eime group. This difference was statistically significant (P<O.05).
From the result that no significant difference was observed in the MIC distribution of the two !rugs for urinary isolates, a possible reason that significantly higher eradication rate was obtained n patients without indwelling catheters in the ceftriaxone group was considered to be attributed to he fact that ceftriaxone maintains effective urinary level for a longer period than cefotaxime.
Clinical adverse reactions were observed in 4.3% of the patients in the ceftriaxone group and in.0% of the patients in the cefotaxime group. Laboratory adverse reactions were observed in 16 latients in the ceftriaxone group and in 8 patients in the cefotaxime group. There were no signifiant difference between the two treatment groups regarding the incidence of clinical and laboratory dverse reactions and ceftriaxone appeared to be as well tolerated as cefotaxime.
From the results obtained in this study, we concluded that ceftriaxone was useful in the treatment f complicated urinary tract infections. Further clinical trials are expected to determine whether or ot once a day treatment of complicated urinary tract infections by ceftriaxone is effective.

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A double-blind comparison of T-2588, a new oral cephem antibiotic, and cefadroxil was carried out in the treatment of complicated urinary tract infections. Patients were randomly assigned to receive either 300mg of T-2588 or 750mg of cefadroxil a day in 3 divided doses for 5 or 7 days by oral administration.
All patients were shown to have pyuria of at least 5 WBCs per high power field, bacteriuria of at least 104 bacteria per ml of urine and identifiable underlying urinary tract disease. The overall clinical efficacy of the treatment was evaluated by the criteria proposed by the UTI Committee in Japan as excellent, moderate or poor based on the combination of changes in pyuria and bacteriuria.
Of the 293 patients evaluated for the clinical efficacy, 153 patients received T-2588 and 140 received cefadroxil. No significant difference in background characteristics was observed between the two treatment groups. Excellent and moderate responses were obtained in 63.4% of the patients receiving T-2588 and in 59.3% of the patients receiving cefadroxil. This difference was not statistically significant.
When the clinical efficacies were compared between the two treatment groups in each types of infection which were classified into 6 categories, no significant difference was observed in any of 6 types of infection.
The overall bacteriological eradication rates obtained were 76.7% of 215 strains in the T-2588 group and 75.6% of 201 strains in the cefadroxil group. This difference also was not significant. Eradication rates achieved for P. aeruginosa were low in both groups. Gram-negative bacilli appeared less frequently after treatment in the T-2588 group than in the cefadroxil group.
Clinical adverse reactions were observed in 4 patients in both groups respectively. Drug related laboratory adverse reactions were observed in 4 patients in the T-2588 group and in 6 patients in the cefadroxil group. There was no significant defference between the two treatment groups regarding.

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