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R B Drotman

Publications and source records attributed to R B Drotman.

13 recordsLinked to original sources

Experimental delayed contact sensitization to diazolidinyl urea (Germall II) in guinea pigs.

Diazolidinyl urea (Germall II) is a new preservative recommended for use in certain consumer products. Although 2 reports document the human sensitization rates of this preservative, no publications quantify its sensitization potential in controlled animal experiments. Diazolidinyl urea induced mild sensitization (grade 2) under maximization test conditions. Further, there was evidence of cross-reactions with both imidazolidinyl urea (Germall 115) and formaldehyde in diazolidinyl-urea-sensitized animals. Rechallenge of diazolidinyl-urea-sensitized animals with diazolidinyl urea 4 weeks following the primary challenge only elicited a weak response (0.5) from 1 animal out of 8.

Animals↗

Development of an objective comedogenicity assay.

The rabbit ear comedogenicity assay is useful as a screening procedure for evaluating agents that come in contact with human skin. Controversy exists regarding the reliability of this assay because of differences in results from various laboratories. The subjective nature of the standard method of grading may also contribute to this variation. We use a more objective comedogenicity assay that utilizes increasing follicular orifice size on the rabbit ear as a measure of comedogenic activity. A generally linear increase in the degree of follicular orifice area was noted with several agents evaluated over a four-week application period. Further, a noninvasive Silastic elastomer mold was used to allow measurement of the same follicular orifice areas over time.

Acne Vulgaris↗

Serum enzymes as indicators of chemically induced liver damage.

Rats were dosed with CCl4 or diethylamine to induce liver injury. The time and magnitude of peak liver injury were assessed by histopathological examination of liver specimens taken at intervals after dosing. Serum enzymes were measured at the same intervals. Serum ornithine carbamyl transferase (SOCT) activity increased at least 6-fold in animals that showed liver damage by histopathology, and fell again as the injuries resolved. Measurements of other enzymes were less sensitive. SOCT measurements appear to be as sensitive a method as histopathology for detecting liver damage caused by administering xenobiotics. Since serum enzyme measurements do not require that the animals be sacrificed, they can be used for repeated examinations of the same animals, thus increasing the likelihood of detecting transient injury.

Animals↗

Occurrence of 5-hydroxy-3-indoleacetic acid in urine from several animal species.

1. The normal levels of 5-hydroxy-3-indoleacetic acid (5HIAA) were determined in the urine of four species of laboratory animals (dog, rabbit, rat and guinea-pig). 2. When 5HIAA excretion was calculated as mg/24 h, the output in the four species was in the order of rabbit greater than dog greater than guinea-pig greater than rat; but when it was calculated as mu/mg of creatinine, the order was guinea-pig greater than rabbit greater than rat greater than dog. 3. There were significant differences in the excretion of urinary 5HIAA between males and females within two species: rats and dogs.

Animals↗