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[Comparison of the antibacterial activity of ticarcillin with other antibacterial agents (author's transl)].

Antibacterial activity of ticarcillin was determined in comparison with that of sulbenicillin, amoxicillin, cefuroxime, clindamycin and metronidazole against anaerobic bacteria which have been isolated from various clinical materials in this hospital. Growth of more than 90% of Gram-negative anaerobic rod bacteria was inhibited by ticarcillin at its concentration of 100 micrograms/ml. Strains resistant to ticarcillin showed cross resistance against both sulbenicillin and amoxicillin. Antibacterial activity of ticarcillin against Gram-positive anaerobic bacteria was found almost equal to sulbenicillin but slightly inferior to amoxicillin. Cefuroxime was found most inferior among the tested six antibiotics when an inoculation level of 10(8)/ml was utilized, but it showed similar activity to ticarcillin when they were tested with 10(6)/ml inoculation. Approximately 10% of bacteroides strains was resistant to clindamycin while all the strains were sensitive to metronidazole.

Amoxicillin

Antibacterial activity detected in duodenal juice.

Antibacterial activity could be detected in bacterium-negative duodenal juice from 3 patients, whereas it was not detected in bacterium-positive duodenal juice from other 3 patients. The follow-up study revealed that appearance of the activity in duodenal juice was just coincident with disappearance of bacteria in duodenal juice. The activity was not influenced by pH of the duodenal juice. These results seem to suggest that some antibacterial activity, different from that of pH, in duodenal juice regulates in some way proliferation of the upper gastrointestinal flora.

Adult

Antibacterial activity of amniotic fluid.

The antibacterial activity of amniotic fluid against Escherichia coli in the last month of pregnancy was reduced in an unselected sample of mothers delivering in Cape Town. Amniotic fluid zinc, required for normal antibacterial activity, was also reduced. These findings offer an explanation for the high incidence of amniotic fluid infection previously reported.

Amniotic Fluid

[Talampicillin hydrochloride: Comparison with amoxicillin and ampicillin in the antibacterial activity and pharmacokinetics (author's transl)].

The antibacterial activities, absorption and excretion of talampicillin hydrochloride were compared with those of amoxicillin and ampicillin. Talampicillin hydrochloride showed a broad-spectrum antibacterial activity against Gram-positive and Gram-negative bacteria as seen in amoxicillin and ampicillin. The antibacterial activities of talampicillin hydrochloride, amoxicillin and ampicillin were quite similar. In experimental murine infection with Staphylococcus aureus, protective effect of talampicillin hydrochloride was superior to ampicillin. For Escherichia coli infection, protective effect of talampicillin hydrochloride was similar to that of amoxicillin, while ampicillin was less active than both talampicillin hydrochloride and amoxicillin. The absorption and excretion of 250 mg equivalent doses of talampicillin hydrochloride, amoxicillin and ampicillin were compared in nine fasting healthy volunteers after oral administration of these antibiotics in randomized triple crossover study. In order to calculate the pharmacokinetic parameters, plasma levels were analyzed using an one-compartment open model, as well as area under the plasma concentration curve (AUC) and urinary excretion. Maximum plasma levels calculated were 2.8 times higher for talampicillin hydrochloride and 1.45 times higher for amoxicillin than for ampicillin. AUC was greater for talampicillin hydrochloride than for amoxicillin and lowest for ampicillin. Urinary excretion of talampicillin hydrochloride as penicillin determined in biological assay was comparable to that of amoxicillin and 1.55 times higher than that of ampicillin. Penicillins can be metabolized to penicilloic acids in the body. After taking into account the penicilloic acid contents in urine, total excretion in urine was 61% for talampicillin hydrochloride, 67% for amoxicillin and 42% for ampicillin during 6 hours after dosing. The absorption of the drugs was evaluated according to the plasma levels, the area under plasma concentration curve and the percentage of excretion in urine. The results obtained showed that talampicillin hydrochloride was well absorbed from the gastro-intestinal tract.

Adult

Antibacterial activity of tooth-colored dental restorative materials.

The antibacterial activity of dental restorative materials (12 resin based and one silicate) was tested in vitro against 5 species of bacteria. When fresh, all materials inhibited growth in pour plates of at least one bacterial strain. After storage in saline for 24 hours, the antibacterial activity was markedly reduced. There was a wide variation among the materials in the extent of their antibacterial activity. The bacterial strains apparently differed in their susceptibility to the antibacterial activity of the materials.

Anti-Bacterial Agents

[In vitro antibacterial activity of fosfomycin].

We have studied the "in vitro" antibacterial activity of phosphonomycin against 93 freshly isolated bacterial strains. Phosphonomycin posses a good activity mainly against Gram positive bacteria. A marked increase in the antibacterial activity "in vitro" is obtained when phosphonomycin is combined with other antibitoics having a similar mechanism of action (i.e. inhibition of cell-wall synthesis). We have also determined the frequency of phosphonomycin-resistant mutants in some of the strains tested for antibacterial activity. High frequency of resistant strains have found in Klebsiella spp.

Anti-Bacterial Agents

The relationship between nicotinamide adenine dinucleotide concentration and antibacterial activity of isoniazid in Mycobacterium tuberculosis.

The relationship between the antibacterial effect of isoniazid and the intracellular concentration of nicotinamide adenine dinucleotide (NAD) was investigated in Mycobacterium tuberculosis strain H37Rv given continuous and pulsed exposures to the drug. Depletion of NAD to a plateau value occurred rapidly during exposure, and recovery after a pulse of isoniazid was also rapid. It seemed unlikely that NAD depletion was the direct cause of the antibacterial activity because (1) insufficient depletion occurred at low isoniazid concentrations; (2) antibacterial activity, but not NAD depletion, was proportional to the product of isoniazid concentration and the exposure period; and (3) NAD depletion was not related to antibacterial activity in cultures of differing physiologic state.

Isoniazid

Evaluation of antibacterial activities of cephalosporin antibiotics: cefazolin, cephaloridine, cephalothin, and cephalexin.

The antibacterial activities of 4 cephalosporin antibiotics, cefazolin, cephaloridine, cephalothin and cephalexin, against 330 isolates of bacteria from patients at National Taiwan University Hospital, were determined by an agar plate dilution technique. Cephalosporins possess strong antibacterial activity against gram-positive bacteria except Enterococci. Staphylococcus aureus is the most susceptible among the organisms tested. More than 90% of Staphylococcus aureus strains are suppressed by cefazolin, cephaloridine and cephalothin at the concentrations of 3.13 mug/ml or less, except that 49.1% are suppressed by cephalexin. The relative potency of cephalosporins against Staphylococcus aureus in decreasing order is cephaloridine, cephalothin, cefazolin, and cephalexin. The gram-negative bacilli, Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis are less susceptible to cephalosporins than the gram-positive cocci. Among the cephalosporins, cefazolin is the most active against the gram-negative pathogens tested. The relative potency of antibacterial activity of cephalosporins against E. coli in decreasing order is cefazolin, cephaloridine, cephalexin, and cephalothin. One hour after the intramuscular injection of 500 mg of cefazolin, the maximum concentration of 33.3 mug/ml is reached in the serum. The sufficient high levels are sustained for 8 hours. Very high concentrations of cefazolin are also found in the urine.

Adult

Antibacterial activity of Artemisia herba-alba.

The antibacterial activity of Artemisia herba-alba was investigated. Only its essential oil was active against some Gram-positive and Gram-negative bacteria. The essential oil was fractionated by column chromatography, and these fractions were tested for antibacterial activity. The principal component of the most active fraction was santolina alcohol.

Africa

In vitro antibacterial activity of drugs against human intestinal anaerobic bacteria.

The in vitro antibacterial activity, against the major groups of anaerobic fecal bacteria, of a series of drugs was examined by an agar diffusion test and the minimum inhibitory concentration (MIC) test. Only the phenothiazines and amitriptyline showed any marked antibacterial activity, the MIC's being in the 40-640-mu-g/ml range. It is suggested that the detergent nature of the molecules of these drugs in aqueous solution is responsible for the observed antibacterial activity.

Amitriptyline

[Bacteriological studies on fosfomycin. Antibacterial activity in vitro and in vivo (author's transl)].

We have examined the antibacterial activity of the new antibiotic, fosfomycin (FOM) in vitro and in vivo. The following results were obtained. 1. FOM showed a broad antibacterial spectrum. 2. The antibacterial activity of FOM was enhanced in the medium at pH 6 and pH 7, and was also influenced by the addition of rabbit serum, calf serum, glucose-6-phosphate or defibrilated sheep blood to the growth medium, and by the size of inoculum. 3 FOM showed especially strong bactericidal action upon the bacteria at the logarithmic phase. 4. FOM showed remarkable therapeutic effect against most strains of gram-positive and gram-negative bacteria tested in experimental infections of mice. 5. The therapeutic effect of FOM was especially remarkable for infection with Salmonella. 6. The therapeutic effect of FOM was more potent than the other drugs tested against infection of Pseudomonas aeruginosa. 7. It seems that FOM is more active in vivo than in vitro with respect to antibacterial activity.

Animals

[Antibacterial activity of sisomicin in comparison with gentamicin].

The antibacterial activity of sisomicin -- a new aminoglycoside antibiotic -- as compared with gentamicin was tested on 521 bacterial strains of different species in a serial-dilution test. Staphylococci, streptococci, E. coli, Klebsialla-Enterobacter, indole-psitive Proteus strains, pseufomonads, Salmonads, Salmonellae, and Serratia marcescens were inhibited to the extent of 100% at a maximun of 4.0 mug/ml. Sisomicin showed a higher antibacterial activity against part of the bacterial species. Gentamicin-resistant pseudomonads and Klebsiella (clinical isolates) were still inhibited to the extent of 42 and 67%, respectively, by sisomicin. In addition to the determination of the MIC values for the use of different liquid media, investigations on the determin ation of the minimal bactericidal concentration (MBC), the effect of serum, pH, and inoculum on the bacterial activity, and investigations on the resistance development in vitro were also carried out.

Anti-Bacterial Agents

[Comparison of the antibacterial activity of amikacin (BB-K8) with other aminoglycosides against pathogens recently isolated from clinical materials (author's transl) ].

We determined the antibacterial activity of amikacin against 1,277 strains of pathogenic bacteria isolated from clinical materials during 1974, including beta hemolytic streptococci, pneumococci, enterococci, Staphylococcus aureus, Staph. epidermidis, Escherichia coli, Klebsiella, Enterobacter, Citrobacter, Serratia, Proteus morganii and Pseudomonas aeruginosa, and compared the minimum inhibitory concentration (MIC) of this drug with gentamicin, dibekacin, tobramycin and kanamycin. 1)Antibacterial activity of amikacin against beta hemolytic streptococci, pneumococci and enterococci was as weak as the other four aminoglycosides, but against Staph. aureus, Staph. epidermidis, various groups of Enterobacteriaceae and Pseudomonas aeruginosa showed amikacin the good antibacterial activity as gentamicin, dibedacin and tobramycin, and also showed the good activity against kanamycin resistant strains. 2) Amikacin has the similar antibacterial spectrum as gentamicin, dibekacin or tobramycin, but its antibacterial activity is generally weakest among these four drugs. 3) On many strains tested the cross resistance is observed between amikacin and one of gentamicin, dibekacin and tobramycin, but several strains of Proteus morganii and Pseudomonas aeruginosa which have rather large MIC against gentamicin, dibekacin or tobramycin showed rather small MIC against amikacin.

Amikacin

[The antibacterial activity of amniotic fluid with a correlation between zinc phosphorus concentrations (author's transl)].

Antibacterial activity of 22 amniotic fluids collected at different stage of pregnancy have been tested against different types of staphylococci: 209 P, 2961 and Escherichia Coli OMS and 83. At the same time zinc and phosphorus concentration in these fluids have been measured. 77 p. 100 of those fluids present an antibacterial activity, but no correlation has been found with their concentration in zinc and phosphorus. Probably this activity is multifactorial and further studies need to be done to identify the factor or factors responsible for that antibacterial activity.

Amniotic Fluid

The peroxidase content and the antibacterial activity of the amniotic fluid.

A possible relationship between the antibacterial activity of amniotic fluid and its peroxidase content was examined. Antibacterial activity, assessed by counting colonies of S. aureus following 24 hour incubation, was present in 76% of the samples studied. It was not related to gestational age. Peroxidase activity, assessed by the O-dianisidine method, was not found in any of the amniotic fluid samples examined.

Amniotic Fluid

Insect immunity. 11. Simultaneous induction of antibacterial activity and selection synthesis of some hemolymph proteins in diapausing pupae of Hyalophora cecropia and Samia cynthia.

We have previously shown that pupae of the giant silkmoth Samia cynthia have a humoral antibacterial activity, which was induced by viable, nonpathogenic gram-negative bacteria (H.G. Boman et al., 1974). We show here that this activity was formed simultaneously with a selective incorporation of amino acids into eight polypeptide chains characterized by their electrophoretic behavior. If actinomycin D or cycloheximide were given at an early time, no antibacterial activity was found. If the inhibitors were given at the time of maximum activity, there was no effect with actinomycin D but a rapid decrease of the activity in the case of cycloheximide. The results imply that the messenger ribonucleic acid was stable, but that at least one protein component was turning over. Hemolymph from immunized pupae of another giant silkmoth, Hyalophora cecropia, was fractionated by ammonium sulfate precipitation. This procedure, together with the isotope distribution after co-electrophoresis in polyarylamide gels, was used for comparing the response to injury and to different infections. Almost identical polypeptide patterns were obtained as a response to an infection with either viable Enterobacter cloacae or Bacillus subtilis. These patterns differed both qualitatively and quantitatively from the injury effect created by an injection as such. There was only a low antibacterial activity in each of the four fractions obtained by ammonium sulfate precipitation. However, a combination of three fractions restored a high killing activity. Fractionation of hemolymph from untreated pupae provided evidence for at least one preexisting factor which stimulated the killing of Escherichia coli. The osmotic pressure of the bacteria contributed to the antibacterial activity towards E. coli, but not towards B. subtitlis. The killing of E. coli was inhibited by liped A and, to a lesser extent, by an inhibitor of proteolytic enzymes. The similarities and differences with the mammalian complement system are discussed.

Animals