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T-8581 is a new water-soluble triazole antifungal agent. The geometric mean IC80s (GM-IC80S; where the IC80 is the lowest drug concentration which reduced the optical density at 630 nm by 80% compared with the optical density at 630 nm of the drug-free control) for Candida albicans were as follows: T-8581, 0.218 microgram/ml; fluconazole; 0.148 microgram/ml; and itraconazole, 0.0170 microgram/ml. For Cryptococcus neoformans the GM-IC80s were as follows: T-8581, 9.28 micrograms/ml; fluconazole, 4.00 micrograms/ml; and itraconazole, 0.119 microgram/ml. For Aspergillus fumigatus the GM-IC80s were as follows: T-8581, 71.0 micrograms/ml; fluconazole, 239 micrograms/ml; and itraconazole, 0.379 microgram/ml. Against systemic candidiasis in mice, the 50% effective doses (ED50s) of T-8581, fluconazole, and itraconazole (given orally) were 0.412, 0.392, and > 320 mg/kg of body weight, respectively. Against systemic aspergillosis in mice, the ED50s of T-8581, fluconazole, and itraconazole (given orally) were 50.5, 138, > 320 mg/kg, respectively. T-8581 was also efficacious when it was given parenterally (ED50, 59.2 mg/kg), while the ED50 of fluconazole given parenterally was > 20 mg/kg. Against systemic aspergillosis in rabbits, T-8581 was more effective than fluconazole and itraconazole in prolonging the life span. The high concentrations of T-8581 were observed in the sera of mice, rats, rabbits and dogs. Species differences in half-lives and areas under the concentration-time curves were observed, with the values for mice, rats, rabbits, and dogs increasing in that order. These results suggest that T-8581 would be a potentially effective antifungal drug for oral and parenteral use.

We study a c=-2 conformal field theory coupled to two-dimensional quantum gravity by means of dynamical triangulations. We define the geodesic distance r on the triangulated surface with N triangles, and show that dim[r^{d_H}]= dim[N], where the fractal dimension d_H = 3.58 +/- 0.04. This result lends support to the conjecture d_H = -2\alpha_1/\alpha_{-1}, where \alpha_{-n} is the gravitational dressing exponent of a spin-less primary field of conformal weight (n+1,n+1), and it disfavors the alternative prediction d_H = -2/\gamma_{str}. On the other hand, we find dim[l] = dim[r^2] with good accuracy, where l is the length of one of the boundaries of a circle with (geodesic) radius r, i.e. the length l has an anomalous dimension relative to the area of the surface. It is further shown that the spectral dimension d_s = 1.980 +/- 0.014 for the ensemble of (triangulated) manifolds used. The results are derived using finite size scaling and a very efficient recursive sampling technique known previously to work well for c=-2., Comment: 12 pages, LaTeX, 4 figures using psfig.sty and epsf.sty

Monte-Carlo simulations of abelian projection of $T \neq 0$ pure lattice QCD show that 1) Polyakov loops written in terms of abelian link fields alone play a role of an order parameter of deconfinement transition, 2) the abelian Polyakov loops are decomposed into contributions from Dirac strings of monopoles and from photons, 3) vanishing of the abelian Polyakov loops in the confinement phase is due to the Dirac strings alone and the photons give a finite contribution in both phases. Moreover, these results appear to hold good with any abelian projection as seen from the studies in the maximally abelian gauge and in various unitary gauges., Comment: 11 pages + 9 figures

Bactericidal activity in compromised host's serum i.e. patients with cancer, the elderly, diabetes, was stronger than that in normal serum against Proteus mirabilis (P. mirabilis) but was weaker against Klebsiella pneumoniae (K. pneumoniae). Against Escherichia coli (E. coli), bactericidal activity on serum of patients with cancer was weaker in the following order, that in elderly serum, that in diabetic serum. Against Proteus vulgaris (P. vulgaris), bactericidal activity in elderly serum was similar to that in normal serum but was stronger than that in serum of patients with cancer. Against Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus), bactericidal activity in elderly serum and diabetic serum was similar to that in normal serum but was weaker than that in serum of patients with cancer. Piperacillin showed bactericidal activity in nutrient broth, normal serum and compromised host's serum at a concentration of 1/4 MIC against E. coli, P. mirabilis and P. aeruginosa. Aspoxicillin showed bactericidal activity in nutrient broth, and bactericidal or bacteriostatic activity in normal serum and serum of patients with cancer against E. coli and P. aeruginosa. While cefazolin and cefmetazole slightly inhibited the growth of bacteria in nutrient broth, they showed hardly any bactericidal activity in normal serum and compromised host's serum.

Built-in TV-systems for TEM image processing and storage are becoming popular in the recent TEM instrumentation. We have completed the development of the H-7100 which has greater expanding capability than the conventional instruments. The H-7100 has been designed around the computer controlled electronics of the H-7000. The new H-7100 electronics is accessible from an external computer including the specimen stage control. When it is coupled with an EDX spectrometer, an automated microanalysis is performed.Fig.l is a system diagram of the specimen stage. The rotation of the DC motor is converted to linear movement by transmission gears and a linear actuator. The linear motion is used to drive the specimen stage. The stage traverse is detected and regulated by numbers of pulse generated by a rotary encoder which is connected to the DC motor. The smallest traverse step of 1nm is available. The pulse signal of the rotary encoder is processed by a computer together with the working magnification to determine the optimum stage traverse. This design allows operator to perform both the low and high magnification work with maximum convenience and comfort. Further, specimen position memory, automatic tracking of the stage traverse and automatic return to a zero position have been incorporated.

Bacteroides fragilis strains were isolated from clinical specimens. B. fragilis G-237 was highly resistant to beta-lactam antibiotics due to beta-lactamase production. The purified enzyme from this strain gave a single protein band on polyacrylamide gel electrophoresis. The isoelectric point was 4.8, and the molecular weight was estimated to be 26,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The enzyme activity was inhibited by p-chloromercuribenzoate and iodine but not by clavulanic acid or sulbactam. The purified enzyme showed a unique substrate profile by hydrolyzing at a high rate most of the cephalosporins, including cephamycin derivatives, penicillins, and imipenem (formerly imipemide, N-formimidoyl thienamycin, or MK 0787).

The susceptibility of 53 clinical isolates of Bacteroides fragilis to cephamycins was examined. Judging from the MICs for 50% of the strains tested, moxalactam was the most active, however, judging from the MICs for 90% of the strains tested, cefbuperazone was more effective than moxalactam. A correlation was observed between in vitro activity of benzylpenicillin and cephaloridine and beta-lactamase production. Inactivation due to enzymatic hydrolysis of cephamycins over a short time was not observed; however, inactivation was detected by a double disk diffusion test, and moxalactam was most easily inactivated. We conclude that inactivation due to enzymatic hydrolysis of cephamycins over a long time may play an important role in resistance to some cephamycins in strains of B. fragilis.

The induction of beta-lactamase in Enterobacter cloacae GN5797 was studied by using 23 beta-lactam antiobiotics, including newly introduced drugs, as inducers. the beta-lactam antibiotics can be classified into three groups on the basis of their inducer activity. Among the tested cephalosporins, cephamycin derivatives such as cefoxitin, cefmetazole, and YM09330 had high inducer activity even at low drug concentrations. On the other hand, cefoperazone, cefsulodin, piperacillin, and apalcillin showed low inducer activity when compared with the other cephalosporins.

The purified cephalosporinase from Proteus vulgaris hydrolyzed a variety of cephalosporins, including cefuroxime, at a high level; its activity was inhibited by clavulanic acid.

The activity of cefoperazone against a strain with an inducible cephalosporinase and a mutant that produces the enzyme constitutively indicates that the low inducer activity of this antibiotic plays an important role in its activity against Enterobacter cloacae.

The inducer activity of seven penicillins for cephalosporinase (CSase) production and their antibacterial activity against CSase-producing strains were studied using clinical isolates of Proteus morganii, P. rettgeri, P. vulgaris, Enterobacter cloacae, and Serratia marcescens. Piperacillin, apalcillin, and methicillin showed rather low inducer activity for CSase production in all strains tested. On the other hand, ampicillin, carbenicillin, and sulbenicillin showed high inducer activity for CSase production. Piperacillin, apalcillin, and ampicillin were less stable to CSases than were carbenicillin, sulbenicillin, and methicillin, but much more stable than benzylpenicillin. In the growing culture of CSase-producing strains, piperacillin and apalcillin were rather stable. Against CSase-producing strains, piperacillin and apalcillin were more active than other penicillins tested.