We tested the sensitivity of C. trachomatis to various kinds of antimicrobial agents (minocycline (MINO), doxycycline (DOXY), erythromycin (EM), TE-031, ofloxacin (OFLX), ampicillin (ABPC) under various conditions.
1) Comparison of HeLa 229 cells (2 different strains supplied by S. P. Wang, Univ. Washington, Seattle, USA and Flow Lab.) and McCoy cells used as culture cells revealed no differences in MIC, except that the MICs for EM were lower 4-5 stages in the case of the HeLa 229 cells suppplied from Wang. We consider HeLa 229 cells suitable as culture cells for MIC determination because they are human origin, but that the use of HeLa 229 cells of one origin needs to be agrreed upon.
2) Examination of inoculum titers revealed higher MICs (1-2 stages) for all drugs at 10⁵ IFU/well than at 10² IFU/welt, but was most easily determined and highly reproducible at 10⁴ IFU/well, indicating that this is an appropriate inoculum titer for the determination of MIC.
3) Comparison of staining methods revealed higher MICs (2-4 times) for MINO, DOXY, EM, TE-031 and OFLX by the direct fluorescent antibody method (DFA) than by iodine staining, but a great difference in MICs for ABPC (128μg/ml by the DFA as 1.0μg/ml for the iodine staining). This suggests that the DFA had not only higher specificity to inclusion bodies, but also higher sensitivity to those drug-affected inclusion bodies undetectable by iodine staining.
Our results indicate that drug sensitivity tests of C. trachomatis should be performed on according to the standard method for determining drug sensitivity of Chlamydia, proposed by the Japanese Society of Chemotherapy, since results vary considerably according to the test conditions.

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We studied optically clear, simple media for broth microdilution testing using the MIC-2000 system (Dynatech Laboratories) with an auto-reader controlled by a personal computer. Streptococcus pyogenes, Streptococcus Pneumoniae and Haemophilus influenzae produced sufficient growth for inoculum preparation in brain heart infusion broth (BHI), cooked meat medium (CM), and hemin (Xfactor) and β-diphosphopyridine nucleotide (V-factor)-supplemented BHI, respectively, and the viable cell counts remained unchanged for 15-22 hours. The MICs were determined in 5% horse serum-supplemented Mueller-Hinton broth, 5 % horse serum-supplemented BHI, and X-and V-factor-supplemented BHI for S. pyogenes, S. pneumoniae and H. influenzae, respectively. The MICs of ampicillin (ABPC), cefazolin (CEZ), cefotiam (CTM), cefmenoxime (CMX) and gentamicin (GM) determined in the aforementioned media by the broth microdilution method agreed approximately with those determined by the standard agar dilution method recommended by Japan Chemotherapy Society, though the MICs of minocycline (MINO) did not agree as well as those of the other antibiotics. Branhamella catarrhalis produced pellets in cation-supplemented Mueller-Hinton broth in static culture, but the cells were dispersed sufficiently for inoculum preparation in shaking culture, and the viable cell counts remained unchanged for 13-20 hours, It was, however, difficult to determine the MICs against B. catarrhalis by auto-reader, since this organism sometimes produced pellets in the microplates for which there was no suitable shaking equipment. We investigated the susceptibility distribution of the four kinds of bacteria clinically isolated in 1989 to the six antibiotics mentioned above by the broth microdilution method.

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We studied the cross-reactivity of imipenem (IPM) in delayed-type hypersensitivity (DTH) by leucocyte migration inhibition test (LMIT) in order to determine the causative drugs in 25 patients displaying hypersensitivity to β-lactam antibiotics and to test their cross-reactivity. Of the β-lactam-hypersensitive patients 5 were penam-hypersensitive, 17 cephem-hypersensitive, and 3 carbapenem-hypersensitive. An LMIT was performed using an indirect agarose plate method. The various suspected causative drugs and 14 other β-lactam antibiotics were used as agents in the cross-reaction test. For each antibiotic, the mean ±2 SD (n=6) of the migration index (MI) for normal individuals was regarded as the normal range (NR). If the MI of the patient was above the NR, this was interpreted as indicating detection of leucocyte migration activating factor. If the patient's MI was below the NR, this was attributed to the detection of leucocyte-migration inhibitory factor. Both cases were regarded as positive. The cross-reaction rate in the LMIT of penam-sensitive patients was 43 %(3/7) for penams, 0%(0/5) for 6-aminopenicillanic acid, and 0%(0/5) for 1PM. The cross-reaction rate of cephem-sensitive patients was 47%(18/38) for cephems, 35%(6/17) for 7-aminocephalosporanic acid, and 0%(0/17) for IPM. Five of 17 cases had no abnormal findings when IPM was administered after the emergence of allergic symptoms. On the other hand, in carbapenem-sensitive patients, only one case of IPM-sensitivity was LMIT-positive to clavulanic acid, all others being LMIT-negative (0/18). Our findings indicate that in DTH there may be very low crossantigenicity between IPM and penams and little between IPM and cephems, but there may be slight cross-antigenicity between IPM and clavulanic acid.

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We examined the therapeutic efficacy of the new quinolon is, ofloxacin (OFLX) and ciprofloxacin (CPFX), against Mycobacterium kansasii induced infection in mice, on the basis of incidence of gross lesions and changes in colony forming units (CFU) of organisms in the visceral organs. The two quinolones exhibited significant therapeutic activity against M. kansasii infection, when given p. o. or i. p. to mice, in a dose of 2mg/mouse, once daily, 6 times per week. The efficacy of OFLX was dose-dependent and higher than that of CPFX. Rifampicin (RFP), as a control drug, given by gavage in a dose of 0.5mg/mouse, exhibited significant efficacy against the infection. The two quinolones showed marked microbicidal activity against M. kansasii ingested by host peritoneal macrophages (MΦs) when added at concentration of 10-20μg/ml to an in vitro culture system, while RFP exhibited significant bactericidal activity even at 2μg/ml, at which concentration the quinolones showed only a bacteriostatic effect.

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Five patients with pleural effusion were given 2 g of sulbactam/cefoperazone (SBT/CPZ) by drip infusion and concentrations of the drug in serum and in pleural effusion were determined. The results obtained were as follows:
1) The serum concentration of SBT and Cl)/peaked immediately after drip infusion and averaged 52.1μg/ml and 122μg/ml. At 24 h after drip infusion SBT disappeared from serum, but CPZ was still detectable in three cases.
2) The pleural effusion concentration of SBT peaked at 6.84μg/ml 2 h after drip infusion, and of CPZ at 7.55μg/ml 6 h after drip infusion. Twenty-four hours after drip infusion, the pleural effusion concentration was 0.58μg/ml for SBT and 5.01μg/ml for CPZ.
3) The rates of the peak pleural effusion concentration/peak serum concentration of SBT and CPZ were 16.3% and 6.0% and the rates of the pleural effusion AUC/serum AUC of SBT and CPZ were 97.8% and 33.6%.

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We carried out basic and clinical studies to evaluate the usefulness of cefuroxime axetil (CXMAX) in dentistry and oral surgery, and obtained the following results.
1. The antibacterial activity of CXM was determined and compared with those of cefaclor (CCL), cefteram (CFTM) and ampicillin (ABPC), against 74 strains clinically isolated at our Department. CMX's activity was slightly superior to those of CCL and CFTM, although inferior to that of ABPC, against Gram-positive organisms (30 strains). Against Gram-negative organisms (44 strains) it was similar to those of CCL and ABPC, but inferior to that of CFTM.
2. The transfer of CXM into oral tissue after administration of 250mg in non-fasting subjects was determind. It transfered equally well into tooth extraction wound and peripheral vein blood. Transfer of CXM into gingiva was comparable or superior to those of the reference antibiotics, the ratio of peak concentrations in gingiva to those in serum being 0.41±0.12.
3. In a clinical evaluation, 12 patients with periodontitis and 2 with ostitis were treated with 750mg or 1, 500mg CXM-AX per day. The efficacy of the treatment was assessed by thedoctors in charge as exellent or good in 10 cases, the efficacy rate being 71.4%. Judged by points efficacy was assessed as excellent or good in 9 cases and the efficacy rate was 64.3%. The only side effect noted was soft stool in one case, but this was mild.
4. We consider CXM-AX to be a safe and useful drug in treating mild or moderate infections in dentistry and oral surgery.

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We studied the effect of norfloxacin (NFLX), a pyridonecarboxylic acid derivative antimicrobial agent, on intestinal bacterial flora in pediatric patients. The subjects were 4 boys and 1 girl aged from 4 years 2 months to 11 years 8 months, and their body weight ranged from 17-34kg. NFLX was administered at a dose of 2.9-5.3mg/kg, 3 times a day for 5-9 days. We quantified and identified bacterial species in faces, and measured fecal concentrations of NFLX and Clostridium difficile D-1 antigen before, during and after the administration of NFLX. Changes in fecal flora during treatment varied among subjects. Of the aerobes, Enterobacteriaceae decreased significantly in all cases. Of the anaerobes, Bifidobacterium tended to decrease in some cases, but no remarkable changes were observed in other main anaerobes, such as Bacteroidaceae. So changes in the total count of anaerobes were small. There was no case in which glucose non-fermenting Gram-negative rods and fungi became predominant species. Neither C. difficile nor C. difficile D-1 antigen were detected. NFLX, at concentrations of 96-480μg/g, was detected in the feces in all cases and in some cases, even 2-6 days after the end of dosing at 2.20-7.15μg/g. Based on our findings, we consider NFLX to be a drug with relatively little effect on intestinal bacterial flora other than Enterobacteriaceae in pediatric patients.

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PURPOSE: The aim of the present study was to evaluate a combined treatment with aspoxicillin (ASPC) and aztreonam (AZT) in 84 patients with respiratory tract infection.
METIIODS: ASPC and AZT were given separately by intravenous injection at respective doses of 2g and 1g twice daily for the first few days until causative organisms were isolated from patients' sputum and cultured. The drugs were then switched to a single administration of either ASPC or AZT: ASPC in the case of Gram-positive cocci and AZT in the case of Gram-negative rods, In cases where both bacteria were ioslated or the causative organisms unknown both drugs were continued. The treatment was assessed as excellent, good, fair, or poor according to the grade of improvement in clinical symptoms and laboratory findings after the beginning of drug administration. The percentage of patients assessed as excellent and good was taken as the efficacy rate. The effect of treatment on the elimination of causative organisms was also evaluated.
RESULTS: 1) The efficacy rate was 78.6%(66 of the total 84 patients), when treatment was assessed independently of choice of drugs.
2) Likewise, categorized by disease, the efficacy rate was 83.7%(36 of 43 patients) in primary pneumonia; 53.3%(8 of 15 patients) in pneumonia or bronchitis secondary to underlying disease of the respiratory tract; 83.3 %(20 of 24 patients) in acute exacerbation of chronic infection of the respiratory tract.
3) Categorized by the severity of infection, the efficacy rate was 55.6 %(5 of 9 patients) in severe infections, 80.9%(55 of 68 patients) in moderate, and 85.7%(6 of 7 patients) in mild.
4) In patients whose drugs were switched to ASPC alone, the efficacy rate was 85.7%(11 of 13 patients); in those to AZT alone, 64.3 %(9 of 14 patients); in those with no change of drug, 80.7%(46 of 57 patients).
5) In patients assigned to this trial because of previous ineffective antibiotic therapy, the efficacy rate was 71.4%(15 of 21 patients).
6) In 34 of the 84 patients causative organisms were identified as Gram-positive cocci (19 cases), Gram-negative rods (13 cases) and both bacteria (2 cases), the biological efficacy rate being 82.4%(28 of 34 patients) and the elimination rate of causative organisms 85.3%(29 of 34 patients).
7) Adverse reactions were found in three patients, namely two cases of fever and one of eruption. Abnormal laboratory findings were observed in 17 patients including 13 events of elevated hepatic transaminase, 5 of eosinophilia and 1 of leukopenia. All of these side effects were slight and did not necessitate withdrawal of drug administration.
CONCLUSION: We conclude that combined treatment with ASPC and AZT may prove beneficial in treating infectious diseases of the respiratory tract.

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