Application of conservation principle in estimating body volume in rats.

Obesity is a risk factor in diving and aviation during acute reduction of pressure, because N2 is five times more soluble in fat than in water. In addition to concerns of decompression applications, body fat content (BFC) bears importance in the disposition of drugs, the evaluation of dietary regimens and exercise programs, and in long-term health status. Most of the currently available methods for quantifying BFC are impractical for small animals. We devised a method that does not require the cooperation of the animal. Our method uses a simple gas-dilution technique to measure the body volume. The body density was determined as the ratio of body weight (g) to body volume (ml). After the whole body density was determined, the fraction of body fat was calculated according to established formulas. Calibration with aluminum blocks showed a high correlation (r = 0.99) between measured volumes and the known block volumes. Furthermore, comparing body volumes of shaved and unshaved rats showed that the volume of air between hairs did not affect the measurement of body volume with the dilution method. In four groups, each consisting of 10 male Wistar rats [body wt 81 +/- 1 (SE), 152 +/- 3,297 +/- 5, and 496 +/- 4 g], BFC was 7.0 +/- 2.8, 14.6 +/- 1.9, 22.0 +/- 1.8, and 32.3 +/- 1.3%, respectively. These values compared favorably with chemically determined BFC values for rats in the literature. Our results suggest that the gas-dilution technique is a feasible and simple method for the determination of BFC in small animals.

Improved early detection of cervical intraepithelial lesions by combination of conventional Pap smear and speculoscopy.

PURPOSE: To evaluate the efficacy of the addition of speculoscopy to a Pap smear in cervical cancer screening. METHODS: All women were screened using the Pap smear plus speculoscopy (PapSure) and colposcopy in the multicenter trial. The final diagnosis of each patient was based on a histological evaluation of the colposcopic target biopsy. Results were analyzed using a proportional compare test, sensitivity, specificity and predictive value with significant value determined at less than 0.05. RESULTS: Of 1,717 eligible cases, 26 cases had LGSIL and 16 cases had HGSIL. Of the Pap smears, five cases had LSIL and 14 cases had HGSIL. Of the combination of the PapSure, 23 cases had LGSIL and 16 cases had HGSIL. The sensitivity of the Pap smear to that of PapSure was calculated at 45.2% and 92.9%, respectively (p < 0.001). The estimated cost to detect a cervical lesion using PapSure is less than that of the Pap smear. CONCLUSION: The addition of speculoscopy along with a Pap smear screening results in early detection of cervical lesions in comparison to the Pap smear alone. This screening combination is also more cost-effective and requires fewer visits to the clinic in comparison to a Pap smear screening alone.