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Serum levels of the adrenal androgens Dehydroepiandrosterone (DHEA) and DHEA-sulfate (DHEA-S) attenuate dramatically with age, independent of cortisol, and have been seen to have beneficial effects on body composition, resting energy expenditure (RER), and lipoprotein values. To study the benefits of DHEA in humans with low DHEA-S, 50 mg of micronized oral DHEA/day was administered to 11 health non-smoking menopausal women on no medications. DHEA was administered for 3 weeks in a randomized double blind placebo controlled design with a 3 week washout period. Blood was drawn for lipoprotein and serum hormone concentrations at the beginning and end of each treatment and placebo period. RER, grip strength, and body composition were also measured before and after each treatment and placebo period. Statistical treatment was by ANOVA in a crossover model. DHEA, DHEA-S, free testosterone and testosterone were significantly increased to levels higher than those seen in normal reproductive age women. DHEA-S and DHEA rose from 74.2 $\pm$ 8.5 $\mu$l/dl to 456.3 $\pm$ 71.5 $\mu$l/dl and from 166.7 $\pm$ 23.9 $\mu$l/dl to 418.5 $\pm$ 29.8 $\mu$l/dl, respectively (p $<$ 0.0001 from placebo). No significant changes were found in RER, grip strength, and body composition. Total cholesterol, HDL, and LDL values did not change significantly; however, there was a significant decrease in triglycerides (TG) (p $<$ 0.05). The findings of this study suggested that oral DHEA administered for 3 weeks did not significantly affect RER, grip strength, or body composition; however, TG were significantly decreased. The level of hormone concentrations studied imply that DHEA may be attenuated by aging and restored by replacement. / Source: Dissertation Abstracts International, Volume: 54-08, Section: B, page: 4036. / Major Professor: David Quadagno. / Thesis (Ph.D.)--The Florida State University, 1993.

Bovine haversian femora were assumed to possess transversely isotropic material symmetry and the elastic properties of this tissue were determined from tests on machined specimens (taken from the cortex of femoral mid-sections) using two different testing techniques; namely, ultrasonic and standard (quasistatic) test machine methods Quasistatic machine testing consisted of performing uniaxial tension and simple torsion tests at a strain rate of approximately 3.5 x 10('-4)(s('-1)). Tensile specimens were tested while having an axial and a diametral extensometer attached concurrently to record axial strain and diametral change in their gage region. Ultrasonic testing consisted of measuring the velocity of longitudinal and transverse waves propagating in various directions in a 5mm bone cube. This technique utilized two transducers located on opposite sides of the specimen to transmit (at a resonance frequency of 2.25 MHz) and receive a continuous ultrasonic sine wave The test data were examined to develop empirical correlations between the quasistatic (test machine) values and ultrasonic measurements. Correlations were also examined for quasistatic elastic properties and the density and mineral content of bone. The results indicate that adequate estimates of the Young's moduli can be made from linear first order regression equations on the appropriate longitudinal velocity of ultrasound. Poisson's ratio can be adequately estimated from linear regression equation involving density. However, adequate estimates of the two independent moduli of rigidity can only be made using linear regression equations on three variables: wave speed, density, and mineral content The stress-strain curves produced during mechanical testing had regions that were slightly nonlinear. These curves also exhibited a sizeable amount of residual (anelastic) strain which was completely recovered in a fairly short period of time (less than thirty seconds). The stress-strain curves produced during torsional tests had a peculiar 'hump' that was characteristic of all specimens of this type / acase@tulane.edu

acase@tulane.edu