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Biomedical subjects

T Ward

Publications and source records attributed to T Ward.

At least 91 records · Page 5Linked to original sources

Metabolism of 4-benzamido-1-[4-(indol-3-yl)-4-oxobutyl]piperidine in rats and monkeys.

1. Studies on the absorption, biotransformation and excretion of the potential anti-hypertensive agent 4-benzamido-1-[4-(indol-3-yl)-4-oxobutyl]piperidine (Wy 23699) have been carried out in monkeys and rats. 2. Absorption of the drug in both species was good, as shown by the relative proportions of radioactivity found in the urine after i.v. and oral dosage. 3. Biotransformation was extensive in both species, but the major routes of metabolism were different. In monkey N-dealkylation gave rise to 4-benzamidopiperidine as the principal metabolite; two other minor metabolites were identified as 2-oxo-4-benzamidopiperidine and 4-benzamido-1-[4-(5-hydroxyindol-3-yl)-4-oxo-butyl]piperidine. In the rat, this latter compound (as its conjugate) was the major metabolite; small amounts of benzamidopiperidine but not 2-oxobenzamidopiperidine were found. 4. There was a marked species difference in the route of excretion. Monkeys excreted greater than 60% dose of the drug in the urine, while rats excreted only 19% by this route. This may reflect the species difference in routes of metabolism, metabolic scission of the drug molecule seen in the monkey favouring renal rather than biliary excretion. The toxicological consequences of this are discussed.

Animals↗

Isolation of a factor with toxohormone properties from mouse tumor cells in culture.

A small molecular weight factor with potent toxohormone activity was recovered from the serum-free culture supernatant of mouse MBQA fibrosarcoma cells. The factor depressed plasma-bound iron levels in mice and inhibited cell-free protein synthesis in microgram doses. Preliminary characterizations suggest that the active material is a small peptide.

Animals↗

Muscle state: reaction and movement time in elbow extension.

Eleven subjects reacted to a randomly timed auditory stimulus by extending their right elbows as rapidly as possible under agonist muscle normal state, pretensed and relaxed conditions. Integrated electromyography (emg) was used to validate and quantify muscle state. Total reaction time was divided into premotor reaction time and motor reaction time components, and elbow movement time was measured under all conditions. Significant differences were observed in the integrated emg between the pretensed and relaxed experimental conditions. Differences were observed in total reaction time and premotor time, but not in motor reaction time or movement time.

Adult↗

Studies with chicks on the growth depressing factor(s) in faba beans (Vicia faba L. var. minor).

The growth response of broiler chicks was improved when they were fed diet containing high levels (greater than 85%) of heat treated as compared to raw faba beans. Pelleting and microwave treatment of faba beans containing 10% moisture resulted in maximal improvements in chick growth rates and feed efficiency of only 6% and 8%, respectively. Steam autoclaving (121 degrees for 20 minutes), extrusion (130 degrees or 152 degrees), or microwave treatment of faba beans containing 18% added water resulted in maximal improvements of 16% in growth rates and 19% in feed: gain ratios. the above study, a time course study of the relationship between faba beans autoclaving time anc chick growth response, and studies with individual faba bean fractions (starch isolate and protein isolate) suggests that processing improves the utilization of faba bean mainly through its effects on components associated with the protein and possibly the hull portions of faba beans. The utilization of faba bean starch is not improved with processing. Although the nature of the growth depressing factor(s) has not been established, the results from this study indicated that the major component does not appear to be a tryspin inhibitor, hemagglutinin, some other heat labile protein, or vicine.

Animals↗

Production of ethylene and other volatiles and changes in cellulase and laccase activities during the life cycle of the cultivated mushroom, Agaricus bisporus.

Nine volatile hydrocarbons, as well as methyl chloride, carbonyl sulphide and carbon disulphide, have been identified by mass spectrometry as products of Agaricus bisporus in the compost used in comerical mushroom beds. Of these, only ethylene showed a pattern of production that could be correlated with developmental phases of the crop, high levels being produced whenever fruit bodies were rapidly enlarging. In laboratory flask cultures, under controlled conditions, high levels of ethylene occurred whenever young fruit bodies entered the expansion phase. The enhanced rate of ethylene production continued over several days, irrespective of whether fruit bodies were removed. Production occurred within the colonized compost; no ethylene was evolved by the fruit body itself. When the first fruit bodies expanded, either in beds or culture flasks, laccase levels in the compost fell and those of a beta-1,4-glucanase (cellulase) rose. The enzyme switch occurred once only, during maturation of the first fruit bodies, whereas an elevated ethylene production was associated with each occasion when fruit body maturation took place. The low level of laccase and high of cellulase characterized the whole of the reproductive stage of A. bisporus, whereas the phasic periods of high ethylene production distinguished between periods of fruit body maturation and intervening resting periods.

Agaricales↗