摘要:

Talampicillin is an ester of ampicillin which is readily hydrolysed on absorption to release ampicillin. It is well absorbed from the gastro-intestinal tract resulting in a greater bioavailability of ampicillin than can be achieved with equivalent doses of ampicillin itself. Dose response studies have confirmed a direct relationship between the dose of talampicillin administered and peak serum ampicillin concentration and urinary excretion of ampicillin. Dosing of ampicillin after food has been shown to adversely affect the total bioavailability of ampicillin. This is not so after dosing with talampicillin. The bioavailability of ampicillin from a 250-mg Talpen® tablet dosed after a large meal was significantly greater than that from 250 mg ampicillin dosed in the fasting state. Studies in volunteer subjects at multiples of the proposed therapeutic dose for periods of up to 28 days have indicated its acceptability, bioavailability and lack of side effects on repeated dosing. The fate of the phthalidyl moiety of talampicillin has been investigated in repeated dose studies and in a single dose study in which radiolabelled talampicillin was administered. The principal metabolite of the phthalidyl moiety in man has been shown to be 2-hydroxymethylbenzoic acid, which is identical to that in experimental animals used for toxicological investigations

ISSN:0009-3157    

DOI:10.1159/000237784

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The sensitivity to penicillin G of pneumococci isolated in Switzerland has been determined by the quantitative tube dilution method. 3 out of 100 strains were relatively insensitive to this antibiotic (minimum inhibitory concentration greater than 0.1 μg/ml), thus confirming observations already made in other countries. These results underline the necessity of routinely testing the sensitivity of pneumococci to penicillin G

ISSN:0009-3157    

DOI:10.1159/000237785

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

With the purpose of obtaining pro-drugs of dapsone and sulfadimethoxine, those chemotherapeutic agents were attached through covalent bonding to starch polymeric dialdehyde (Sumstar-190). The antimalarial activity of the two resulting compounds – the dapsone saccharidic polymer (PS6) and the sulfadimethoxine saccharidic polymer (PS7) – in mice experimentally inoculated with Plasmodium berghei was significantly increased with this molecular modification. Mice infected with malaria and kept without treatment together with others which received different doses of PS6 and PS7 were also partially or totally cured, possibly due to the ingestion of excrements containing the parent chemotherapeutic age

ISSN:0009-3157    

DOI:10.1159/000237786

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The in vitro activity of sisomicin and netilmicin alone and in combination with nafcillin, oxacillin and methicillin against 30 strains of enterococci was investigated. Sisomicin and netilmicin alone were not very effective against enterococci. There was enhanced killing of some strains of enterococci by the combination of sisomicin or netilmicin with one of the three penicillinase-resistant penicillins. Nafcillin was the most effective penicillinase-resistant penicillin in the combination. Sisomicin appeared to be slightly more effective than netilmicin in combination with one of the penicillinase-resistant penicillins against enterococci.

ISSN:0009-3157    

DOI:10.1159/000237787

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Hydroxyurea (HU) and cytosine arabinoside (Ara-C) eliminate R factor R46 from Escherichia coli strain J5-3. The highest frequency of elimination for both drugs occurred at concentrations and times that produced the lowest survivor levels, 5% of cells were antibiotic-sensitive after 5 h incubation in 5 mg/ml Ara-C, whilst 6 and 7% of the survivors had lost the R factor after 8 and 24 h incubation, respectively in 20 mg/ml HU. The number of survivors began to increase after 5 h incubation in Ara-C, probably due to the inactivation of the drug in the phosphate-buffered medium. All four antibiotic resistances (ampicillin, streptomycin, sulphonamide and tetracycline) mediated by R46 were lost simultaneously and elimination of the whole plasmid was confirmed by conjugation experiments in which the ‘cured’ cells was shown to be as efficient recipients of R46 as the control R–– strain in crosses with E. coli strain J6-2 (R46). No covalently closed circular plasmid DNA was demonstrable in cured cell lines. R+ and R–– strains had similar sensitivities to HU but J5-3 R+ was much more sensitive to Ara-C than the isogenic R–– strain. It may be concluded that HU eliminates R46 actively whereas although Ara-C may produce some active elimination it acts mainly by selection of R–– cells pre

ISSN:0009-3157    

DOI:10.1159/000237788

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The response of Escherichia coli to nalidixic acid was investigated by continuous turbidimetric monitoring of cultures exposed to the drug. Two distinct types of turbidimetric response were detected when dense populations of E. coli were exposed to nalidixic acid in a static system, but this difference was not found in low-inoculum experiments, nor in experiments in which initially dense inocula of E. coli were exposed to the drug in conditions similar to those encountered in the treatment of bacterial cystitis. Stable resistance to nalidixic acid was readily induced in cultures of E. coli. Such resistance emerged by a step-wise process and cultures could easily be converted to resistance to at least 64 μg nalidixic acid per millilitre by sequential transfer. Resistance to drug levels greater than 64 μg/ml was more difficult to induce and such variants were unstably resistant to the higher drug levels. ‘Wild’ nalidixic-acid-resistant E. coli were correspondingly found to be partially susceptible to concentrations of nalidixic acid exceeding 64 μg/ml. Nalidixic acid resistance was even easier to induce in an in vitro model of the treatment of bacterial cystitis than in the static system, in that a single cycle of exposure to a ‘dose’ of the drug allowed the emergence of a population exhibiting a relatively high level of resistance. It is suggested that the therapeutic efficiency of nalidixic acid resides in a highly effective initial onslaught, and that, if infection is not controlled at this stage, the emergence of resistance is likely to be a cause of therapeut

ISSN:0009-3157    

DOI:10.1159/000237789

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Pretazettine hydrochloride (PTZ) has been found to inhibit protein synthesis, without being inhibitory to DNA and RNA, in Rauscher leukemic blood cells in mice for at least 6 h after its administration. With comparison to Virazole and cycloheximide, the specific anti-Rauscher virus activity of PTZ has been demonstrated only in acutely-infected NIH/3T3 cells but not in chronically-infected cells. It is not certain that the inhibitory action of PTZ on reverse transcriptase is contributory to its therapeutic activity in leukemic mice.

ISSN:0009-3157    

DOI:10.1159/000237790

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

In a effort to estimate the incidence of clinical ototoxicity in children we reviewed the charts of 374 patients who had serum gentamicin concentration determined 30 min before (‘trough value’) and at the pharmacologic peak after parenteral administration. 37 of these patients, between 9 and 17 years of age, had two or more audiograms; of these, 9 developed objective evidence of hearing loss; in 2 the impairment was severe and permanent. Risk factors associated with ototoxicity were renal failure, concomitant administration of diuretics and peak serum concentrations greater than 12 μg/ml (all significant at p < 0.01). The minimum incidence of overt hearing loss secondary to gentamicin therapy is approximately

ISSN:0009-3157    

DOI:10.1159/000237791

出版商:S. Karger AG    

年代:1978

数据来源: Karger

ISSN:0009-3157    

DOI:10.1159/000237792

出版商:S. Karger AG    

年代:1978

数据来源: Karger