Biomedical subjects

T D David

Publications and source records attributed to T D David.

3 recordsLinked to original sources

PubMed1987

Renal medullary solute depletion resulting from psychogenic polydipsia in a rhesus monkey.

A rhesus monkey developed psychogenic polydipsia after a change in feeding regimen was instituted. Hyposthenuria, hyponatremia, hypochloremia, and an abnormal calculated plasma osmolality were found. Water deprivation testing and administration of antidiuretic hormone indicated that renal medullary solute depletion had resulted from the prolonged polyuria. Restricted water consumption resulted in resolution of the electrolyte abnormalities and restored ability to excrete concentrated urine.

Animals↗

PubMed1987

Rewarming of the hypothermic rhesus monkey with electromagnetic radiation.

To obtain more detailed information relative to the potential usefulness of using radio frequency (RF) energy in treating hypothermia, anesthetized rhesus monkeys were used in a rewarming study that compared a conventional method (heating pad) with an RF induction coil system. Rectal temperature (Tre) of each subject was monitored, and enzyme and isoenzyme levels were determined from blood samples collected before, during, and up to 48 h after hypothermia in order to assess the effects of each rewarming method. The previously observed postprocedure rise in serum enzymes (most visible at 24 h) was again seen, with no statistically significant difference in the time course of serum enzyme levels between the two treatments for comparable durations of hypothermia. To test the limits of the ability of the RF induction coil system, successively more severe hypothermia was induced in the subjects to the point of cardiovascular collapse (Tre less than 20 degrees C); RF energy was successful in resuscitating the profoundly hypothermic subjects without discernible harmful effects.

Alanine Transaminase↗

PubMed1979

Species differences in decompression.

In an effort to bring together the diverse laboratory-animal decompression studies, a literature review and statistical evaluation were undertaken. Although 22 different species that had been used in decompression studies were identified, systematic data were available for only 7 of these species: man, goat, dog, guinea-pig, rat, hamster, and mouse. Mathematical functions using physiological data on these seven species were developed to estimate 1) saturation time (the time for the body to equilibrate after an increase in hydrostatic pressure), and 2) no-decompression saturation-exposure limits (the maximum saturation-exposure pressure from which an abrupt return to 1 ATA can be tolerated). Data from man, rat, and mouse were used to develop physiological relationships for two additional decompression variables: change in pressure-reduction limits associated with increased exposure pressure and time to onset of decompression symptoms. Finally, data on rats for two other decompression variables, gas elimination time and optimum decompression stop time, are discussed in the hope that this will stimulate additional animal laboratory research in other mammalians. The general functional relationships developed in this paper provide a preliminary and rough means for extrapolating among species the decompression results obtained during animal laboratory experiments.

Animals↗