The present paper describes conjugal transfer experiments where the transfer of penicillinase production (AP^r) and tetracycline resistance (TC^r) determinants have been demonstrated with clinical isolates of Branhamella catarrhalis.
Transfer of APr determinant from arbitrarily chosen 18 penicillinase positive B. catarrhalis strains to a susceptible strain of the same genus has been demonstrated, with all strains tested, in both primary and secondary conjugations at a frequency between 10^-3 and 10^-7 per donor.
Transfer of TC^r determinant from 4 TC resistant strains to a susceptible B. catarrhalis was also demonstrated at a frequency of 10^-4 to 10^-5 per donor.
In conjugation where some double resistant strains carrying both AP^r and TC^r determinants were used as the donors, segregation of these determinants among the transconjugant cells was observed, suggesting that these two may be mediated by different transferable factors, each other.

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The haemolytic and protease activi ties of E. faecalis and E. faecium in the blood, urine and bile of patients were compared with those of the same organisms in the feces of healthy volunteers. The drug susceptibility of the two groups of isolates were also compared.
Strains of E. faecalis and E. faecium were mainly present in clinical specimens of blood and urine and a wide range of species of D group Streptococcus were present in the feces. The frequency of the strains of E. faecalis with haemolytic activity was higher in the clinical specimens (blood, urine and bile) than in the fecal specimens. And this was also the case with protease activity. The frequency of strains with both activities was also higher in the clinical specimens than in the fecal specimens. This was also true of E. faecium.
The fecal isolates, regardless of haemolytic or protease activity, were significantly more susceptible to various antibiotics than were these isolates from the blood and urine.

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Guinea pigs were given daily intramuscular injection of RSM 200 mg/kg, 400 mg/kg, AMK 100mg/kg, 200 mg/kg, AKM 100 mg/kg, 200 mg/kg for 28 days.
They were experimented with Preyer reflex, cochlear microphonics and NBT reducibility, and the results are as follows;
1) Animals receiving AMK 200 mg/kg, AKM 100 & 200 mg/kg caused decrease in formazan production in OHC & IHC in answer to the loss or dull of Preyer reflex in frequency range of 20 kHz to 10 kHz. From these results it was concluded that the changes in Preyer reflex is corresponded to the changes in NBT reducibility.
2) Animals receiving AKM 200 mg/kg caused decrease in NBT reducibility both in OHC & IHC, and the decline of CM was only observed at this dose.
3) The ototoxic effect of aminoglycoside antibiotics has been reported that the loss of OHC progresses from basal turn to the upper, but not in IHC. From this results of NBT reducibility, the disappearance or decline of NBT reducibility was observed in OHC and a matter of degree in IHC. It was presumed that when the first ototoxicity after aminoglycoside antibiotics injection appeared, some organic changes occur not only in OHC but in IHC.
4) Ototoxic effect on cochlea in guinea pigs receiving 10 or 20 times of clinical dose of aminoglycoside antibiotics daily i. m. injection for 28 days was AKM>AMK>RSM in order, and RSM was not toxic. From these results it was presumed that for setting up the doses of ototoxic experiment it is necessary to refer to acute toxicity as well as to maximum recomended clinical dose based on antibiotic activity and to consider wide extent of doses.

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Contact hypersensitivity induced by picryl chloride (PC) was applied to investigate the effect of antibiotics on cellular immunity in mice.
Penicillins in β-lactam showed a little effect on induction phase of delayed type hypersensitivity, but TIPC, PIPC and MZPC which did not have phenylacetamide side chain group inhibited the swelling of the ears when injected at the effector phase. Methyltetrazolyl group at the 3-position and aminothiazolyl group at the 7-position in cephems appeared to relate on inhibition of the induction and effector phase, respectively. Inhibition of both phases was observed in cephamycins, and especially CMZ showed the strongest inhibition. In aminoglycosides, GM and AMK showed marked inhibitory activity on induction phase, whereas only DKB was effective on effector phase. The strength of inhibition to contact hypersensitivity did not relate to the serum levels of the drugs at 1-hr after the injection.
These results suggest that the contact hypersensitivity could be a marker to estimate the effects of antibiotics on cellular immunity and to elucidate their mechanism.

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The action of piperacillin (PIPC) at the tubular secretion site was studied in rabbits, as compared with probenecid.
When probenecid was co-administered with PIPC or cefazolin (CEZ) in rabbits, which are mainly secreted from renal tubule the serum levels of CEZ were elevated and prolonged, and its urinary excretion was significantly decreased. PIPC was also influenced by probenecid, however, the effect of probenecid on the serum levels and urinary excretion of PIPC was less than that on CEZ. These findings reveal that PIPC has a high affinity to tubular secretion system.
To study these findings in detail, serum levels of CEZ following its i.v. administration of 20mg/kg were determined under a drip infusion of PIPC or probenecid. Although serum levels of PIPC under its drip infusion of 0.97mg/kg/min. were 2-3 times higher than those of probenecid under its drip infusion of 0.16mg/kg/min., in these cases there was no significant difference in the serum levels and serum half-life of CEZ. The same results were obtained under a drip infusion of 2.65mg/kg/min. of PIPC and 0.47mg/kg/min. of probenecid.
From these results, the inhibition ability of PIPC on the tubular secretion seemed to be 1/2-4/3 times that of probenecid.

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Haemophilus influenzae is the most important pathogen in patients with chronic respiratory tract infections (CRTIs). The acute exacerbation caused by H. influenzae is characterized recurrence at short interval in such patients.
Beta-lactam antibiotics combined with macrolides, tetracyclines, or new quinolones to prevent recurrent respiratory infections caused by H. influenzae in present study. Ninety five infection episodes caused by H. influenzae out of 216 episodes, which ocurred from 1983 to 1985 in 26 patients with CRTIs, were subjected to this study.
The efficacy was defined as no H. influenzae infections during 1 month immediately after the combination chemotherapy. The efficacy rates were 31.4%(11/35) in combination with beta-lactam antibiotics and macrolides, 55.0%(11/20) in combination with beta-lactam antibiotics and tetracyclines, 47.1%(16/34) in combination with beta-lactam antibiotics and new quinolones, 50.0%(3/6) in other combination chemotherapy, and 43.1%(41/95) in total. No statistically significant differences were found among these four combination chemotherapy. The efficacy rates were not significantly different between intravenous administration of beta-lactam antibiotics and per oral administration, the rates being 35.3%(6/17) and 42.4%(25/29), respectively.
No side effects were observed in all the patients in this study.

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The efficacy, safety and utility of ciprofloxacin were compared in a double-blind clinical trial with those of norfloxacin in the treatment of skin and soft tissue infections. Either drug was orally administered at a dosage of 200 mg t. i. d.(before breakfast, after lunch and at bedtime). Patients over the age of 15 were randomly allocated to one of the two groups.
A total of 318 patients were enrolled in this study. One hundred fifty five patients received ciprofloxacin and 163 received norfloxacin. An assessment of efficacy could be made in 140 patients having received ciprofloxacin and 142 patients having received norfloxacin. Safety was assessed in 146 patients on ciprofloxacin and in 155 patients on norfloxacin. Utility was evaluated in 141 patients on ciprofloxacin and in 143 patients on norfloxacin. Utility assessment was done on the basis of clinical responses, side effects and severity of the disease.
“Cure” or “Remarkable improvement” was seen in 106 ciprofloxacin patients (75.7%) and in 94 norfloxacin patients (66.2%).“Cure”, “Remarkable improvement” or “Improvement” was seen in 123 ciprofloxacin patients (87.9%) and 117 norfloxacin patients (82.4%). The difference was statistically significant (P<0.05). No statistical difference was seen in overall safety assessment. Seventy-two patients (51.1%) on ciprofloxacin and 53 patients (37.1%) on norfloxacin were assessed as “Remarkably useful”.“Remarkably useful” or “Useful” was seen in 118 ciprofloxacin patients (83.7%) and 108 norfloxacin patients (75.5%). The difference was statistically significant (P<0.05).
Bacteria were eradicated in 66 (81.5%) of 81 ciprofloxacin patients with a positive culture and 58 (67.4%) of 86 norfloxacin patients with a positive culture. The difference statistically tended to be favorable for ciprofloxacin (P<0.1).
Clinical side effect or abnormal laboratory tests were not significantly different in either frequency or nature between the two groups. All adverse effects were of a mild nature.
From these results we concluded that ciprofloxacin is more useful than norfloxacin at least in the treatment of skin and soft tissue infections.

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