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Biomedical subjects

R D Meyer

Publications and source records attributed to R D Meyer.

At least 145 records · Page 8Linked to original sources
PubMed1976

Antibacterial activity of selected beta-lactam and aminoglycoside antibiotics against cephalothin-resistant Enterobacteriaceae.

The in vitro antibacterial activity of four beta-lactam antibiotics (cefatrizine [BL-S640], cefamandole, cefoxitin, and carbenicillin) and three aminoglycosides (amikacin, gentamicin, and tobramycin) was determined against 197 strains of cephalothin-resistant Enterobacteriaceae. Eighty strains were found to be gentamicin-sensitive, and 117 were found to be gentamicin-resistant. Carbenicillin was the most active beta-lactam antibiotic against gentamicin-sensitive Serratia marcescens and Enterobacter spp. Cefoxitin was the most active beta-lactam antibiotic against the remaining gentamicin-sensitive and -resistant Enterobacteriaceae, including Providencia stuartii and indole-positive Proteus spp. Cefatrizine exhibited little activity against the organisms studied. Cefamandole was less active than cefoxitin and carbenicillin. Amikacin was the most effective agent in vitro. With the exception of S. marcescens, cefoxitin appeared to be the next most promising agent in vitro against gentamicin- and cephalothin-resistant Enterobacteriaceae.

Aminoglycosides↗
PubMed1976

Abnormal hydroxyproline polypeptides in the urine of patients with chronic uremia.

An abnormal peak of hydroxyproline polypeptides has been observed when the polypeptide fraction from the urines of patients with advanced chronic uremia was subjected to gel chromatography. This abnormality was apparently related to the degree of uremia and to the presence of uremic osteodystrophy. The abnormal peak was not observed in patients with high turnover bone disease without renal insufficiency and in patients with nephrotic syndrome and normal glomerular filtration rate.

Chromatography, Gel↗
PubMed1975

Determination of hydroxyproline polypeptides in urine and blood serum by gel filtration.

Hydroxyproline-containing polypeptides were isolated from urine by filtration on polyacrylamide gel Bio-Gel P-2. This fraction was quantitatively and qualitatively similar to the nondialysable hydroxyproline in urines of normal adult subjects, patients with chronic uremia, and with primary or secondary hyperparathyroidism. Hydroxyproline polypeptides isolated from urines of patients with extensive Paget's disease or from normal growing subjects contained a group of smaller polypeptides slightly retarded on Bio-Gel P-2 which were not retained by the dialysis membrane Spectrapor-TM. In these two groups of subjects the values of hydroxyproline polypeptides were 35-45 percent higher than those of dialysable hydroxyproline. Increased excretion of hydroxyproline polypeptides was found in chronic uremia, primary and secondary hyperparathyroidism, Paget's bone disease and in normal growing subjects. With the notable exception of chronic uremia the excretion of hydroxyproline polypeptides paralleled that of total and oligopeptidic hydroxyproline. In some cases of chronic uremia the polypeptidic hydroxyproline represented the predominant fraction. On long columns of Bio-Gel P-6 hydroxyproline polypeptides separated into several peaks. The chromatographic pattern was rather characteristic for chronic uremia, secondary hyperparathyroidism, Paget's bone disease and physiological growth. Ahydroxyproline fraction of similar chromatographic properties was isolated from blood serum after deproteinisation with heat or ethanol at pH 4.8. High serum levels of this hydroxyproline fraction were observed in pathological conditions with increased urinary excretion of polypeptidic and nondialysable hydroxyproline.

Adenoma↗
PubMed1975

Amikacin therapy for serious gram-negative bacillary infections.

Amikacin is a new aminoglycoside antibiotic pharmacologically similar to kanamycin. It has a wide range of activity against Gram-negative bacilli, including many resistant to gentamicin. Thirty-six serious Gram-negative bacillary infections were treated with amikacin. Twenty-nine patients (80-6%) responded (cured or improved). Twelve of 13 patients with gentamicin-resistant pathogens responded. Minor ototoxicity occurred in 6 patients and was associated with prolonged therapy or previous aminoglycoside therapy. Possible nephrotoxicity with amikacin was found in 6 patients. Amikacin should be used primarily to treat suspected or known gentamicin-resistant pathogens.

Adult↗
PubMed1971

Tobramycin (nebramycin factor 6): in vitro activity against Pseudomonas aeruginosa.

Tobramycin (factor 6 of the nebramycin complex) is a new aminoglycoside antibiotic isolated from Streptomyces tenebrarius which is active against S. aureus, Enterobacteriaceae, and Pseudomonas aeruginosa. Susceptibility to tobramycin of 96 strains of P. aeruginosa, including 45 recent isolates from blood, was studied by using agar and broth dilution methods. The minimum inhibitory concentration (MIC) for 83 of 96 strains was 3.12 mug/ml or lower in Mueller Hinton agar; MIC values were two to eight times lower in Mueller Hinton broth tests. Agar dilution MIC values were generally lower than those obtained in parallel tests with gentamicin. Killing curves obtained from serial sampling of broth cultures showed a 100- to 10,000-fold decline in viability of log-phase organisms within 30 min of exposure to the drug. Two-dimensional agar dilution tests with carbenicillin and tobramycin with 79 strains showed additive or synergistic effects; no antagonism was documented. Seventy-eight of 79 strains were inhibited by a combination of 50 mug of carbenicillin per ml and 1.56 mug of tobramycin per ml, blood levels which seem attainable in man. Tobramycin appears to be a potent, rapidly bactericidal antibiotic against P. aeruginosa and merits clinical evaluation.

Agar↗