Internal dosimetry of 210Pb in the human cranium: preliminary results from instrumentation needs for in vivo counting in a low-background underground counting facility.

Internal dosimetry of (210)Pb in the cranium deals with the determination of the amount of energy deposited in tissue by (210)Pb radiations within the cranium. (210)Pb in the human cranium was monitored by in vivo counting in a low background facility 640 m (2100 ft) underground with a germanium (Ge) gamma-ray detector having a beryllium window. The minimum detectable activity (MDA) was established with this system to be 0.

Seasonality of 214Bi activity in the human body and of 222Rn concentration in home ambient air.

We studied the seasonal variation of the environmental radon progeny (214)Bi activity in the whole bodies (WB) of women and men participating in community-based studies at the Grand Forks Human Nutrition Research Center (GFHNRC), the (214)Bi background activity of the GFHNRC whole body counter (WBC) steel room, and ambient air (222)Rn concentration in the homes of Grand Forks residents, over the 1988-2004 time period. In this cross-sectional epidemiological study, (214)Bi activity in women and men, in the WBC steel room, and (222)Rn concentration in resident homes fluctuated such that the highest values were observed in winter and the lowest in summer, respectively. (214)Bi activity in the WB of human subjects was higher in women who have more (214)Bi activity per unit mass than men.

Natural distribution of environmental radon daughters in the different brain areas of an Alzheimer disease victim.

Background: Radon is a ubiquitous noble gas in the environment and a primary source of harmful radiation exposure for humans; it decays in a cascade of daughters (RAD) by releasing the cell damaging high energy alpha particles.

Results: We studied natural distribution of RAD 210Po and 210Bi in the different parts of the postmortem brain of 86-year-old woman who had suffered from Alzheimer's disease (AD). A distinct brain map emerged, since RAD distribution was different among the analyzed brain areas.

Controlled substitution of soy protein for meat protein: effects on calcium retention, bone, and cardiovascular health indices in postmenopausal women.

In a controlled feeding study, the effects of substituting 25 g soy protein for meat on calcium retention and bone biomarkers were determined. Postmenopausal women (n = 13) ate two diets that were similar, except that, in one diet, 25 g high-isoflavone soy protein (SOY) was substituted for an equivalent amount of meat protein (control diet), for 7 wk each in a randomized crossover design. After 3 wk of equilibration, calcium retention was measured by labeling the 2-d menu with (47)Ca, followed by whole-body counting for 28 d.

Controlled high meat diets do not affect calcium retention or indices of bone status in healthy postmenopausal women.

Calcium balance is decreased by an increased intake of purified proteins, although the effects of common dietary sources of protein (like meat) on calcium economy remain controversial. We compared the effects of several weeks of controlled high and low meat diets on body calcium retention, using sensitive radiotracer and whole body scintillation counting methodology. Healthy postmenopausal women (n = 15) consumed diets with similar calcium content (approximately 600 mg), but either low or high in meat (12 vs.

Association of dominant somatotype of men with body structure, function during exercise, and nutritional assessment.

This study examined the hypothesis that somatotype determines body structure, functional responses at peak exercise, and nutritional status of 63 men ages 18-40 years who lived under controlled conditions. Data were grouped by dominant somatotype to emphasize differences in body types. Dominant ectomorphs (n = 19) had less (P < 0.