Bacterial transmigration as an indicator of time of death.

Time of death is difficult to evaluate in many forensic science situations. We have developed an animal model for assessing the time of death by evaluating the transmigration of normal microbiota through the wall of the small intestine. A segment of small intestine was removed from decapitated CF-1 mice ( Carnsworth Farms) and suspended in vitro in a beaker containing sterile phosphate-buffered saline. Bacterial transmigration was evaluated in this model over a three-day period at select temperatures (4, 25, and 37 degrees C) by microbiological cultures and scanning electron microscopy (SEM). Evidence of bacterial transmigration by SEM occurred within 2 to 3 h at 37 degrees C, 5 to 6 h at 25 degrees C, and 72 h at 4 degrees C. Analysis of the microbiological data indicated a differential flux of select bacterial and mycotic organisms. Staphylococcal species were the first organisms to be cultured from the suspending saline. These organisms are known to elaborate powerful protease enzymes that may play an important role in the degeneration of gut tissues. Coliform-type organisms and candida species were found at later times after death. The last major groups of bacteria to be identified were a variety of anaerobic species. This model may be adaptable to certain situations in human forensic pathology.

Influence of danazol on cytoplasmic and nuclear estrogen binding capacity in the uterus.

Sprague-Dawley rats with estrous cycles were exposed to danazol (Danocrine) at a single dose of 10 mg/kg for either 6 or 24 hours, or daily until a pattern of no cycles (6 days) was noted on vaginal smears. The animals were individually housed and exposed to a 14-hour light/10-hour dark environment. Prior to drug administration, daily vaginal smears were obtained to ensure cycle normalcy. After the appropriate exposure to medication, the animals were killed, the uterine horns were removed, and determination was made of cytoplasmic and nuclear estrogen receptors. The animals in the control group (6 and 24 hours, and daily injected) received vehicle only (mineral oil). The influence of danazol on sex-steroid receptor levels appeared to be related to the phase of the estrous cycle at the time of sacrifice. At both 6 and 24 hours of exposure to danazol, there was a slight decrease in specific estrogen binding capacity of cytosols, with no alteration in the levels of nuclear receptors in the uteri of rats with cycles. In the groups with no cycles, there was an increase in cytosolic estrogen binding capacity at 1 and 6 days of danazol treatment, with a slight decrease in nuclear receptor binding when compared with treated rats with cycles. Statistical evaluation revealed a significant difference in cytosolic estrogen binding capacity between the series with cycles and the series without cycles (p less than 0.01). This study provides further information in regard to danazol action on cytosol and nuclear receptors correlated with phase of the estrous cycle.

Influence of certain prostaglandin synthetase inhibitors on cytoplasmic estrogen receptors in the uterus.

Prostaglandin synthetase inhibitors are widely used in the treatment of primary dysmenorrhea. They are thought to act by inhibiting endometrial synthesis of prostaglandins and subsequently altering endometrial receptor concentration. Since prostaglandins are known to vary with the menstrual cycle in women, implicating an effect associated with sex steroid hormones, we examined the influence of certain prostaglandin synthetase inhibitors on specific estrogen binding capacity of uteri from rats. Ibuprofen (Motrin), 25 mg/kg, indomethacin (Indocin), 15 mg/kg, mefenamic acid (Ponstel), 25 mg/kg, and sulindac (Clinoril), 40 mg/kg, were evaluated at 6 and 24 hours after injection. Specific estrogen-binding capacity was elevated twofold by mefenamic acid; the other agents showed no statistically significant effect. No alteration in the dissociation constant values of the estrogen receptors was observed with these agents. These data suggest that prostaglandin synthetase inhibitors do not influence the estrogen response mechanism in rodents.

A simplified in vitro assay of delayed hypersensitivity in diagnosis of dermatomycoses.

A tissue culture technique for detection of cellular hypersensitivity in an animal model of dermatomycoses is presented. It is based on specific inhibition of migration of leukocytes sensitized to dermatophytic antigens. The application and specificity of this new immunological technique were studied in guinea pigs infected with Trichophyton rubrum, Microsporum vanbreuseghemii, and Epidermophyton floccosum. In all the infected animals, sensitivity to trichophytin was demonstrated to be independent of the clinical disease phase. The in vivo skin-test reactions were common to those of the group of dermatophytes and did not distinguish between the different species. A statistical difference was observed in the leukocyte migration indices of sensitized cells to the homologous and the heterologous antigens of these pathogens (p less than 0.05, Student's test). It is concluded that the leukocyte migration inhibition assay provides a specific expression of cellular hypersensitivity and may be considered suitable for investigation of cellular immunity in vitro in clinical diagnosis or research. This is a simple, rapid, and inexpensive technique that requires small volumes of peripheral blood.