Semiautomated segmentation of ovarian follicular ultrasound images using a knowledge-based algorithm.

The application of a knowledge-based segmentation method to the problem of automatically detecting the outer follicle wall boundary in ultrasonographic images of ovaries is presented. A combination of computer detection and interactive adjustment was used to define an approximate inner follicle-wall boundary, which was then used by the computer algorithm as a priori knowledge to automatically find the outer follicle-wall border. The segmentation algorithm was tested on ultrasonographic images of women's ovaries that were imaged in vivo.

Anthropometric equations for studying body fat in pregnant women.

Anthropometric data from 200 pregnant women were used to estimate body fat at gestation weeks 14 and 37 and changes in body fat from week 14 to week 37 with four formulas from the literature. The resulting estimates were evaluated against the estimation of fat by a four-compartment model that determined fat from weight, total body water, bone mineral mass, and body density. The estimates of fat by existing anthropometric models were statistically different from those by the four-compartment model in both early and late pregnancy.

Relative and interacting effects of sex, race, and environment upon body cell mass in healthy adults.

Most epidemiologic studies in nutrition have concentrated on body fat and obesity because of associated health risks, while few studies have examined factors that influence body cell mass (BCM). The relative influences of sex, race, environment, and age upon BCM were compared by analyzing the results of bioimpedance analyses in two cohorts of 1094 healthy adults, including Africans in Zaire, plus African Americans and Caucasians in New York City. Men were taller, heavier, and had a larger BCM and fat-free mass (FFM) than women, while women had more fat than men.

Effects of ethnicity, gender, obesity, and age on central fat distribution: Comparison of dual x-ray absorptiometry measurements in white, black, and Puerto Rican adults.

Population based studies relying primarily upon anthropometric surrogates of fat distribution have shown that central or upper-body adiposity is related to ethnicity, gender, age, and total body fatness. As an improvement over anthropometry, dual x-ray absorptiometry (DXA) provides more precise measurements of fat mass (FM) in the total body and trunk. DXA was performed on 510 apparently healthy White (81 females (f), 64 males (m)), Black (94 f, 79 m), and Puerto Rican (102 f, 100 m) adults aged 20-75 years in order to determine and compare the effects of race, gender, age, and total FM on trunk FM.

Active Imaging through Cirrus Clouds.

The presence of clouds of ice particles in the uplink and downlink path of an illumination beam can severely impede the performance of an active imaging system. Depending on the optical depth of the cloud, i.e.

High speed optical tomography system for imaging dynamic transparent media.

We describe the design and operation of a high speed optical tomography system for measuring two-dimensional images of a dynamic phase object at a rate of 5 kHz. Data from a set of eight Hartmann wavefront sensors is back-projected to produce phase images showing the details of the inner structure of a heated air flow. The tomographic reconstructions have a spatial resolution of approximately 2.

Three-dimensional surface reconstruction using optical flow for medical imaging.

The recovery of a three-dimensional (3-D) model from a sequence of two-dimensional (2-D) images is very useful in medical image analysis. Image sequences obtained from the relative motion between the object and the camera or the scanner contain more 3-D information than a single image. Methods to visualize the computed tomograms can be divided into two approaches: the surface rendering approach and the volume rendering approach.

Body fat and water changes during pregnancy in women with different body weight and weight gain.

Objective: To determine the fat deposited during pregnancy in women gaining according to recommendations of the Institute of Medicine and the relationship of weight gain to fat gain in women of different starting weights (classified by their body mass index).

Methods: A cohort study of healthy, nonsmoking women, 18-36 years of age, identified during prenatal visits at three hospital clinics and one birthing center in New York City. From a pool of 432 eligible volunteers who signed a consent form, body composition measurements were performed on 200 women at weeks 14 (+/-2) and 37+ of pregnancy, and bone mineral mass was measured at 2-4 weeks postpartum.

Assessment of development of the testes and accessory glands by ultrasonography in bull calves and associated endocrine changes.

The testes, prostate and vesicular glands of 10 bull calves were examined by ultrasonography every 2 wk from 2 to 46 wk of age, at which time the scrotal circumference (SC) of all the calves had reached pubertal size (28 cms). Computer-assisted image intensity analysis (numerical pixel values) was conducted. Blood samples were collected every other week from 2 to 46 wk of age.

Ultrasonography of the developing reproductive tract in ram lambs: effects of a GnRH agonist.

In spring-born ram lambs, the testes (from 2 wk), prostate and vesicular glands (from 4 wk) were examined by ultrasonography every 2 wk up to 26 wk of age. Image analysis was done (numerical pixel values). Ram lambs were treated with a long acting formulation of a GnRH superagonist (Leuprolide acetate; 1.

Appendicular skeletal muscle mass: effects of age, gender, and ethnicity.

This study tested the hypothesis that skeletal muscle mass is reduced in elderly women and men after adjustment first for stature and body weight. The hypothesis was evaluated by estimating appendicular skeletal muscle mass with dual-energy X-ray absorptiometry in a healthy adult cohort. A second purpose was to test the hypothesis that whole body 40K counting-derived total body potassium (TBK) is a reliable indirect measure of skeletal muscle mass.

Density of fat-free body mass: relationship with race, age, and level of body fatness.

The two-compartment body composition method assumes that fat-free body mass (FFM) has a density of 1.100 kg/l. This study tested the hypothesis that FFM density is independent of race, age, and body fatness.

A multi-center comparison of dual energy X-ray absorptiometers: in vivo and in vitro soft tissue measurement.

Objective: To assess intra- and inter-site soft tissue variability by dual energy X-ray absorptiometry (DXA).

Design: Cross-sectional trial.

Setting: Three medical research institutions.

Anthropometrics do not influence dual X-ray absorptiometry (DXA) measurement of fat in normal to obese adults: a comparison with in vivo neutron activation analysis (IVNA).

Dual-energy X-ray absorptiometry (DXA) is now a commonly used method for the determination of bone mineral status and body composition in humans. The purposes of this study were to compare fat mass by in vitro neutron activation analysis (FMIVNA) with that by DXA (FMDXA) in an anthropometrically heterogeneous sample of healthy adult men (n = 33) and women (n = 36) (19 < or = BMI < or = 39), and to determine whether differences in fat mass estimates between the two methods (delta FM) were attributable to subject anthropometry as defined by several circumference (waist, iliac crest, thigh) and skinfold thickness (umbilical, suprailiac, abdominal) measurements. No significant differences between FMDXA and FMIVNA were observed in men (p = 0.

A modified bottle manikin phantom for in vivo neutron activation analysis.

An artificial skeleton was designed and placed inside a bottle manikin absorber phantom to provide a new reference standard for measurements of total body calcium by in vivo neutron activation analysis at Brookhaven National Laboratory. The composition of the epoxy-based calcium and phosphorus mixture used to construct the skeleton, the dimensions and weight of each bone are given for two phantoms representing an adult male and female. Also, the dimensions, composition, and weights of overlays designed to simulate the influence of obesity on in vivo neutron activation analysis are given for each.

Hyperacute lung rejection in a pig-to-human transplant model: the role of anti-pig antibody and complement.

Background: The physiology of hyperacute rejection of pig lung by human blood and the role of antispecies antibody and complement in this phenomenon have not previously been characterized.

Methods: Human blood was perfused through an ex vivo pig heart-lung preparation. In the treatment groups, blood was either unmodified or modified to deplete alternative pathway complement (heat treatment), anti-pig antibody, or both.

Expression of human decay accelerating factor may protect pig lung from hyperacute rejection by human blood.

Background: Hyperacute rejection currently prevents clinical application of discordant lung xenografts. Pigs transgenic for human regulators of complement activation offer one promising potential solution to this problem.

Methods: Using fresh human blood in an ex vivo lung perfusion model, we studied eight different strains of pigs transgenic for human decay accelerating factor.

How important is health promotion in the lifestyle of infertile couples?

Unlabelled: We sought to elucidate the current attitudes and practices of infertile couples concerning unhealthy lifestyle practices, and examine the extent to which the couples engaged in health promoting activities.

Methods: The study population consisted of consecutive couples who first attended an infertility clinic at a tertiary care clinic between July 1, 1995 and June 30, 1996, and voluntarily completed a questionnaire centered on knowledge, attitude and practices pertaining to unhealthy lifestyles as well as health promoting activities.

Results: The majority of the 106 couples 53%, reported cigarette smoking by at least one partner; 69% admitted to alcohol consumption; and 77% were using over-the-counter drugs.

Measurement of body composition: applications in hormone research.

Measurements of body composition are fundamental to the diagnosis and management of a number of diseases. However, these measurements must be appropriate and accurate. Accuracy can now be achieved, but at the expense of invasiveness (mainly radiation) and cost.

Ultrasound image attributes of the bovine corpus luteum: structural and functional correlates.

Nulliparous heifers (n = 58) were studied to determine whether computer-assisted quantitative echotexture analysis of ultrasound images reflects the functional and histomorphological characteristics of the corpus luteum. The ovaries of heifers were examined daily by transrectal ultrasonography from day -2 (day 0 = ovulation) until the day of ovariectomy during metoestrus (day 3; n = 8), early dioestrus (day 6; n = 9), mid-dioestrus (mean, day 10; n = 7), or pro-oestrus (mean, day 18; n = 8; Expt 1). High resolution ultrasound images of corpora lutea were obtained in vitro, and were digitized and analysed using custom-developed computer algorithms optimized for ultrasonography.

Hemodynamic exercise testing. A valuable tool in the selection of cardiac transplantation candidates.

Background: Peak exercise oxygen consumption (Vo2), a noninvasive index of peak exercise cardiac output (CO), is widely used to select candidates for heart transplantation. However, peak exercise Vo2 can be influenced by noncardiac factors such as deconditioning, motivation, or body composition and may yield misleading prognostic information. Direct measurement of the CO response to exercise may avoid this problem and more accurately predict prognosis.

Application of bioimpedance analysis for estimating body composition in prepubertal children infected with human immunodeficiency virus type 1.

The purpose of this study was to evaluate the performance of bioimpedance analysis (BIA) in the prediction of total body water and fat free mass with the use of standard equations in assessing 20 prepubertal children infected with human immunodeficiency virus (HIV). Total body water was measured by means of deuterium oxide dilution, fat free mass by means of total body dual X-ray absorptiometry, and BIA with a bioelectrical impedance analyzer. The use of standard prediction equations resulted in substantial error.

Magnetic resonance imaging of bovine ovaries in vitro.

A sample of 20 bovine ovaries were imaged in vitro using nuclear magnetic resonance (NMR) techniques to determine the visibility of various physiologic structures. In particular, the possibility of using NMR imaging to differentiate atretic follicles from physiologically selected and ovulatory follicles was examined. Five of the 20 ovaries were preserved in formalin, whereas the remaining 15 were preserved in a saline solution and imaged within 18 hours of death.

Prediction of body cell mass, fat-free mass, and total body water with bioelectrical impedance analysis: effects of race, sex, and disease.

The inability to precisely estimate body composition with simple, inexpensive, and easily applied techniques is an impediment to clinical investigations in nutrition. In this study, predictive equations for body cell mass (BCM), fat-free mass (FFM), and total body water (TBW) were derived from direct measurements through use of single-frequency bioelectrical impedance analysis (BIA) in 332 subjects, including white, black, and Hispanic men and women, who were both healthy control subjects and patients infected with the human immunodeficiency virus (HIV). Preliminary studies showed more accurate predictions of BCM when parallel-transformed values of reactance were used rather than the values reported by the bioelectrical impedance analyzer.