Speciation of 581 strains of enterococci isolated from March 1983 through October 1983 revealed that these isolates include S. faecalis (494), S.faecium (50), S.avium (22) and strains difficult to identify to species (15). Thirty-two (S.faecium ;29, S.faecalis; 2, S.avium ;1) out of the 581 enterococcal strains were resistant to ampicillin. Twenty-seven out of these 32 resistant strains were recovered from urine. In vitro tests for sensitivity to 12 antibiotics were performed with 46 ampicillin resistant strains of S.faecium and 4 strains of S.avium by agar dilution technique. All strains were resistant to penicillin G, ampicillin, piperacillin, methicillin, cefasolin and ceftisoxime. Lincomycin and erythromycin showed bimodal MIC distribution, with MIC₈₀, of 1.6μg/ml. MIC₈₀ of gentamicin and amikacin was 25μg/ml and 50μg/ml, respectively. Chloramphenicol inhibits most of the resistant strains at a concentration of 6.3μg/ml. Minocycline was less active than chloramphenicol.

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The pharmacokinetics of dibekacin concerning the renal accumulation were studied in the normal rabbits and infected rabbits whose right kidneys were caused dysfunction by the ascending infection with Escherichia coli O-124.
The elimination half-lives (T _1/2β) were 155min. in the infected rabbits and 73.4min. in the normal rabbits. There was no difference in the renal clearances, cumulative urinary excretion amounts, and renal levels of dibekacin between the right and the left kidneys in the normal rabbits. In the infected rabbits, however, the renal clearances, the cumulative urinary excretion amounts and the renal levels of dibekacin in the ipsilateral kidneys were about 80% of those in the contralateral kidneys. There was a good linear relationship between the ratio of the renal dibekacin levels of the right to the left kidneys and the ratio of the cumulative urinary excretion amounts of the right to the left kidneys. It is considered that the renal accumulation of dibekacin is proportional to the amounts of the drug excreted from the kidneys into urine.

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We examined the susceptibility to 43 antibiotics of 343 pathogenic strains of Staphylococcus aurcus lately in Japan. The susceptibility to 22 beta-lactam antibiotics was already reported, so in this paper, remaining 21 antibiotics are studied with special regard to the prevalence and treatment of multiply resistant strains.
The rate of resistant strains against streptomycin, kanamycin, gentamicin, amikacin, habekacin and fradiomycin were 89%, 45%, 37%, 32%, 9% and 32%, respectively, so resistant strains against aminoglycosides except habekacin increased markedly. Resistant strains against macrolides had not increased for several years and resistant strains against doxycycline decreased.
Almost of all strains containing multiply resistant strains were susceptible against rifampicin, minocycline, vancomycin, sulfamethoxazole-trimethoprim and fusidic acid. However a lot of multiply resistant strains were resistant against both aminoglycosides and beta-lactam antibiotics except clozacillin, dicloxacillin and flucloxacillin.
Because the overbreak of multiply resistant Staphylococcus aureus infection may occur from now in Japan as in U. S. A., it is very important to observe and to prevent the spread of the multiply resistant strains. We recommend that the infections due to multiply resistant strains are treated by cephaloridine, rifampicin, minocycline, vancomycin, sulfamethoxazole-trimethoprim, fusidic acid and isoxazolyl penicillins except oxacillin.

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343 strains of Staphylococcus aureus lately isolated from patients in 45 hospitals distributed throughout Japan were examined in their susceptibility to 43 antibiotics and coagulase typing. The susceptibilities of them were already reported, so, in this report the coagulase typing of 343 isolates, their distribution and the correlation between coagulase types and antibiotic susceptibility were described.
343 strains were divided into 9 groups, that is, type I(8 strains), type II(81 strains), type III(51 strains), type IV(66 strains), type V(17 strains), type VI(7 strains), type VII(99 strains), type VIII(12 strains) and non-typable (2 strains). The strains grouped into type IV or type V were more frequently isolated from pus than other specimens, and type VIII strains were more frequently isolated from blood specimens than the others. Each group of 8 coagulase types was observed almost equally from northern part of Japan to southern part, but the distribution of 8 coagulase types was varied from hospital to hospital. In some hospitals, almost of all isolates were belonged to the same coagulase type group, and this fact suggested the hospital infection.
The most of multiply resistant strains against antibiotics belonged to coagulase type IV group, and lesser strains belonged to type II group. Very few strains of multiply resistant strains belonged to other coagulase type groups.
Almost of all isolates of Staphylococcus aureus was able to be divided into 8 groups by the coagulase typing, while it was reported that about a half of isolates was non-typable by the phage typing.
Moreover, the multiply resistance against antibiotics seemed to be related to coagulase type IV more than other types.
From these results, it is concluded that the coagulase typing of Staphylococcus aureus is important and useful to survey and to prevent the hospital infections by Staphylococcus aureus, especially by multiply resistant strains.

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A systemic antifungal agent miconasole (base) had a potent in vitro activity against a wide range of pathogenic fungi including those associated with deep-seated and subcutaneous mycoses; it inhibited all of 155 testing strains of stock cultures at drug concentrations of 10μg/ml or less when tested by the agar dilution techniques. Similarly, clinical isolates from patients with various systemic mycoses were also highly susceptible to miconasole. Its MIC values to most of 54 isolates were less than 1.25μg/ml. The miconasole activity was greater than that of amphotericin B and ilucytosine as the reference Rystemic antifungal agent.

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A simple and reliable diffusion bioassay for a systemic imidazole antimycotic miconazole, in which yeast-form cells of Blastomyces dermatitidis was employed as the indicator organism, was developed. The assay was sensitive to less than 0.05 and 0.002μg/ml of the drug dissolved in human serum and saline, respectively. With this bioassay procedure, the serum concentration of miconazole in patients of deep-seated mycoses was measured at intervals after intravenous infusion of 200 to 600mg of the drug. The peak serum concentration of 1.0 to 1.6μg/ml occurred at the end of the infusion, decreasing rapidly to about one-forth as low as the peak level after 7 to 8hours. Cerebrospinal fluids from the patients with cryptococcal meningitis who had received intrathecal administration of 10 mg of miconazole contained greater than 0.2μg/ml of drug even after 72 hours. A brief discussion of clinical implication of body fluid levels of miconazole in its therapeutic efficacy.

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Therapeutic efficacy of miconazole (base) administered parenterally was tested in the model of disseminated candidiasis in mice. Seven miconazole intravenous doses of 12.5 to 50mg/kg/day once or twice daily in C.albicans-infected mice significantly increased the survival rate compared with a placebo injection during the two-weeks postinfection observation period. Sufficiently favorable results were also obtained when intravenous administration was delayed for 24 hours after infection. Comparable with the increase of the survival rate, colony counts from the kidney of miconazole-treated mice were markedly reduced compared with those of untreated controls. After intravenous injection of 50mg/kg of miconazole in normal mice, the serum concentration of 30μg/ml was occurred after 15 minutes, thereafter decreasing rapidly.

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