Search PubMed⌕ Search

Biomedical subjects

M J Allison

Publications and source records attributed to M J Allison.

At least 91 records · Page 5Linked to original sources

Clinical and pharmacological studies of ticarcillin in gram-negative infections.

Twenty-seven patients with serious gram-negative infections were treated with ticarcillin in an average daily dosage of 237 mg/kg (range, 174 to 307 mg/kg). Ticarcillin was bactericidal for all infecting organisms in concentrations ranging from 31.2 to 125 mug/ml. Five of 8 patients (62%) with overwhelming Pseudomonas pneumonia were cured or improved, and 9 of 12 (75%) were cured of pneumonia caused by other gram-negative organisms. Of six extrapulmonary infections caused by Pseudomonas, five (83%) were cured or improved. In seven cases, the infecting organism reisolated during therapy was more resistant to ticarcillin than the primary isolate. The serum half-life of ticarcillin in three patients with renal failure was 11.2 +/- 1.0 h, and during hemodialysis it decreased to 6.3 +/- 1.8 h. There were two episodes of superinfection with resistant organisms. Thirteen patients (48%) manifested eosinophilia, one of whom had severe urticaria. Prolongation of bleeding time was attributable to ticarcillin in two patients. Ticarcillin appears to be effective for therapy of serious gram-negative infections in dosages 30 to 50% less than those recommended for carbenicillin.

Adult↗

Inactivation of Clostridium botulinum toxin by ruminal microbes from cattle and sheep.

Toxin from Clostridium botulinum type C was rapidly inactivated during incubation in vitro with ruminal contents from either a cow or a sheep. Fractions of ruminal contents from which cells had been removed by high-speed centrifugation did not inactivate toxin. Inactivation was associated with fractions containing bacteria, whereas fractions containing protozoa and relatively few bacteria were much less active. This activity may help explain the relatively greater tolerance by ruminants to oral doses of botulinum toxin than to toxin administered by other routes. The results are also pertinent to assays for botulinum toxin from gastrointestinal samples obtained postmortem.

Animals↗

Effect of intravenous L-isoleucine infusion upon concentration of free isoleucine in milk.

The growth of Streptococcus agalactiae in milk is inhibited by elevated free isoleucine. Free amino acid concentrations in both plasma and milk from three lactating dairy cows were studied after intravenous infusions of L-isoleucine at 62, 300, 380, and 840 mumol/kg of body weight. Free isoleucine was lower in milk than in plasma. The concentration of free isoleucine in plasma increased after infusions of isoleucine at the three higher amounts. The highest concentration of free isoleucine in milk measured was 1.5 mumol/100 ml of skin milk. This was observed after infusion of isoleucine for 12 h at 380 mumol/kg of body weight. Free isoleucine in both plasma and milk dropped to the preinfusion concentrations a short time after the isoleucine infusions were stopped. When relatively large quantities of isoleucine were infused into the blood of cows, free isoleucine in blood increased as much as twofold. The source of free isoleucine in milk appeared to be free isoleucine in plasma, but isoleucine in milk only reached concentrations that would give about 50% of the growth inhibition of S. agalactiae obtainable with isoleucine in vitro. It would be difficult to elevate free isoleucine in milk by dietary manipulation sufficiently to inhibit S. agalactiae.

Amino Acids↗

Diaphragmatic.

Explore the source record for details and available documents.

Hernia, Diaphragmatic↗

Transportation delay and the microbiological quality of clinical specimens.

An in-use study was done to determine the effect of transportation delay on the microflora of clinical specimens collected for microbiological analysis in a 1,000-bed university hospital. Portions of wound, respiratory, and urine specimens were planted for bacterial isolation on the wards immediately after collection. The remainder of each specimen was kept at room temperature without or without holding medium until it was picked up by messengers and taken to the bacteriology laboratory. The results of immediate planting on the ward were compared with those obtained by planting in the laboratory. Alterations in microflora were observed in all three types of specimens after averages of 2 to 4 hours of delay in planting.

Humans↗

Preliminary study of appearance of endotoxin in circulatiory system of sheep and cattle after induced grain engorgement.

Edotoxin was detected, using the limulus amebocyte lysate (LAL) test, in the blood of 3 sheep and 1 steer which had been experimentally "overfed" (induced grain engorgement) with a mixture of corn and oats (2:1). The 1st postfeeding blood samples were collected 24 hours after overfeeding. In 2 sheep and 1 steer, the 24-hours blood samples were test positive. In 1 sheep which died, the 48-hour blood sample was the 1st test-positive sample. In all cases, pre-overfeeding blood samples were taken just before overfeeding.

Animal Feed↗

Grain overload in cattle and sheep: changes in microbial populations in the cecum and rumen.

Samples from the rumen and cecum of cattle and sheep were cultured to determine changes in microbial populations resulting from overfeeding with grain. Before the animals were overfed, the predominant organisms from both sides were those that grew anaerobically on a relatively nonselective ruminal fluid medium and would not grow on selective mediums designed to culture lactobacilli, streptococci, coliforms, or Clostridium perfringens. By 24 hours after overfeeding, lactic acid bacteria had increased in numbers so that they were the most numerous organisms in both the rumen and the cecum. The concentrations of coliforms and C perfringens also increased after overfeeding and were generally higher in the cecum than in the rumen.

Animal Feed↗

Tryptophan biosynthesis from indole-3-acetic acid by anaerobic bacteria from the rumen.

Microbes in ruminal contents incorporated (14)C into cells when they were incubated in vitro in the presence of [(14)C]carboxyl-labeled indole-3-acetic acid (IAA). Most of the cellular (14)C was found to be in tryptophan from the protein fractions of the cells. Pure cultures of several important ruminal species did not incorporate labeled IAA, but all four strains of Ruminococcus albus tested utilized IAA for tryptophan synthesis. R. albus did not incorporate (14)C into tryptophan during growth in medium containing either labeled serine or labeled shikimic acid. The mechanism of tryptophan biosynthesis from IAA is not known but appears to be different from any described biosynthetic pathway. We propose that a reductive carboxylation, perhaps involving a low-potential electron donor such as ferredoxin, is involved.

Anaerobiosis↗