We studied the mechanism of membrane damage induced by (-) epigallocatechin gallate (EGCg) isolated from extracts of Camellia sinensis (green tea). The amount of EGCg adsorbed by Staphylococcus aureus was 1.5 to 3 times as much as that of EGCg adsorbed by Escherichia coli and Salmonella Typhimurium. This result indicates that the difference in antibacterial activity of EGCg between Gram-positive and Gram-negative bacteria depends on the amount of EGCg adsorbed across the surface of these organisms. The adsorption of EGCg to S. Typhimurium wild type (SL696) was lower than that of EGCg to S. Typhimurium lipopolysaccharide (LPS) mutants (SL1069 and TA2168). This result suggests that LPS on outer membranes of Gram-negative bacteria inhibit adsorption of EGCg to the surface of organisms. There were, however, no significant differences in MIC of EGCg among these strains of S. Typhimurium. To further explore the mode of action of EGCg, we compared the membrane-damaging activities of EGCg and polymyxin B (PL-B). EGCg damaged phosphatidylcholine (PC) liposome membranes and caused leakage of 5, 6-carboxyfluorescein (CF) encapsulated in the liposomes. However, phosphatidylserine (PS) contained in PC liposomes inhibited CF-release dose-dependently, and the release was inhibited at 5 mol% of PS. On the other hand, CF-release from PC liposomes caused by PL-B was in proportion to the amount of PS contained in the liposome membrane. It seems that the membrane damage induced by EGCg and PL-B depends on the electrical property of the material. We, therefore, assume that the net charge of EGCg is negative, since positively-charged PL-B binds negatively-charged lipid bilayers.

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Fever with granulocytopenia (FGP), which occurs in patients with hematological malignancies, is a condition which strongly appears infections, but for which no causal microorganisms or infectious foci can be identified. Patients with FGP were concomitantly given cefpirome (CPR) with amikacin (AMK), with the following results:
(1) 45 subjects resulted in 74 accumulated hospital admissions, 5, 426 accumulated days of hospitalization, and fevers exceeding 38°C during 14.3% of their accumulated hospital days.
(2) In 76.6% of patients, fevers presumably caused by infection, and 40.6% of these infectious fevers corresponded to FGP.
(3) 85.5% of the FGP showed fever reduction after administration of either antibacterial or antifungal agents, indicating that the fevers were resulting from either bacterial or fungal infections.
(4) Concomitant administration of CPR and AMK demonstrated a high level of efficacy, in 72.7% of patients with FGP.
On the basis of these results, combination therapy with CPR and AMK is considered to be effective in patients with FGP.

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We evaluated the permeability of levofloxacin (LVFX) and sparfloxacin (SPFX) into prostatic tissue in patients with benign prostatic hypertrophy. Twenty six patients were studied; 13 for LVFX and 13 for SPFX. LVFX and SPFX were orally administered at a dose of 200 mg two hours and six hours, respectively, before transurethral resection of the prostate. Blood sample and prostatic tissue samples were taken during the operation. The serum concentration of LVFX was significantly higher than that of SPFX (2.42±0.66μg/ml in LVFX vs. 0.63±0.26μg/ml in SPFX, p<0.01). The prostatic concentration of LVFX was significantly higher than that of SPFX (3.25±0.87μg/gm in LVFX vs. 0.68±0.35μg/gm in SPFX, p<0.01). The ratio of prostatic tissue level to serum level of LVFX and SPFX was 1.43±0.48 and 1.07±0.45, respectively. There was no significant difference between the two drugs. Our study suggested that LVFX and SPFX are pharmacologically equivalent as treatments for prostatitis.

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For treatment of female acute uncomplicated cystitis, a single-dose of 200 mg levofloxacin (LVFX) was administered to 31 patients (group A), and 100 mg/day of LVFX was given for 7 days to 34 patients (group B). The clinical results were compared between the two groups in accordance with the UTI Drug Efficacy Evaluation Criteria of Japan. An excellent effect was observed in 23 (74.2%) and 30 (88.2%) cases, a good effect in 8 and 4 cases in groups A and B, respectively; the overall effectiveness rate was 100% in both groups. As regards adverse side effects, immediate type skin eruption was observed in one case in group B. Recurrence was seen in 2 cases in group A, but none in group B. There was, however, no significant difference between the two groups. It was observed with pulsed-field gel electrophoresis that the genomic DNA pattern of the organism isolated at recurrence corresponded to that at the first presentation in all two recurrent cases. This fact strongly suggested that recurrences are attributable to the same organism family. In conclusion, single-dose LVFX therapy was clinically useful for female acute uncomplicated cystitis.

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