Plasma selenium biomarkers in low income black and white americans from the southeastern United States.

Biomarkers of selenium are necessary for assessing selenium status in humans, since soil variation hinders estimation of selenium intake from foods. In this study, we measured the concentration of plasma selenium, selenoprotein P (SEPP1), and glutathione peroxidase (GPX3) activity and their interindividual differences in 383 low-income blacks and whites selected from a stratified random sample of adults aged 40-79 years, who were participating in a long-term cohort study in the southeastern United States (US). We assessed the utility of these biomarkers to determine differences in selenium status and their association with demographic, socio-economic, dietary, and other indicators. Dietary selenium intake was assessed using a validated food frequency questionnaire designed for the cohort, matched with region-specific food selenium content, and compared with the US Recommended Dietary Allowances (RDA) set at 55 µg/day. We found that SEPP1, a sensitive biomarker of selenium nutritional status, was significantly lower among blacks than whites (mean 4.4 ± 1.1 vs. 4.7 ± 1.0 mg/L, p = 0.006), with blacks less than half as likely to have highest vs. lowest quartile SEPP1 concentration (Odds Ratio (OR) 0.4, 95% Confidence Interval (CI) 0.2-0.8). The trend in a similar direction was observed for plasma selenium among blacks and whites, (mean 115 ± 15.1 vs. 118 ± 17.7 µg/L, p = 0.08), while GPX3 activity did not differ between blacks and whites (136 ± 33.3 vs. 132 ± 33.5 U/L, p = 0.320). Levels of the three biomarkers were not correlated with estimated dietary selenium intake, except for SEPP1 among 10% of participants with the lowest selenium intake (≤ 57 µg/day). The findings suggest that SEPP1 may be an effective biomarker of selenium status and disease risk in adults and that low selenium status may disproportionately affect black and white cohort participants

Plasma Selenium Biomarkers in Low Income Black and White Americans from the Southeastern United States

Biomarkers of selenium are necessary for assessing selenium status in humans, since soil variation hinders estimation of selenium intake from foods. In this study, we measured the concentration of plasma selenium, selenoprotein P (SEPP1), and glutathione peroxidase (GPX3) activity and their interindividual differences in 383 low-income blacks and whites selected from a stratified random sample of adults aged 40–79 years, who were participating in a long-term cohort study in the southeastern United States (US). We assessed the utility of these biomarkers to determine differences in selenium status and their association with demographic, socio-economic, dietary, and other indicators. Dietary selenium intake was assessed using a validated food frequency questionnaire designed for the cohort, matched with region-specific food selenium content, and compared with the US Recommended Dietary Allowances (RDA) set at 55 µg/day. We found that SEPP1, a sensitive biomarker of selenium nutritional status, was significantly lower among blacks than whites (mean 4.4±1.1 vs. 4.7±1.0 mg/L, p = 0.006), with blacks less than half as likely to have highest vs. lowest quartile SEPP1 concentration (Odds Ratio (OR) 0.4, 95% Confidence Interval (CI) 0.2–0.8). The trend in a similar direction was observed for plasma selenium among blacks and whites, (mean 115±15.1 vs. 118±17.7 µg/L, p = 0.08), while GPX3 activity did not differ between blacks and whites (136±33.3 vs. 132±33.5 U/L, p = 0.320). Levels of the three biomarkers were not correlated with estimated dietary selenium intake, except for SEPP1 among 10% of participants with the lowest selenium intake (≤57 µg/day). The findings suggest that SEPP1 may be an effective biomarker of selenium status and disease risk in adults and that low selenium status may disproportionately affect black and white cohort participants

Operationalization of community-based participatory research principles: assessment of the national cancer institute\u27s community network programs

ObjectivesWe examined how National Cancer Institute-funded Community Network Programs (CNPs) operationalized principles of community-based participatory research (CBPR).MethodsWe reviewed the literature and extant CBPR measurement tools. On the basis of that review, we developed a 27-item questionnaire for CNPs to self-assess their operationalization of 9 CBPR principles. Our team comprised representatives of 9 of the National Cancer Institute's 25 CNPs.ResultsOf the 25 CNPs, 22 (88%) completed the questionnaire. Most scored well on CBPR principles of recognizing community as a unit of identity, building on community strengths, facilitating colearning, embracing iterative processes in developing community capacity, and achieving a balance between data generation and intervention. CNPs varied in the extent to which they employed CBPR principles of addressing determinants of health, sharing power among partners, engaging the community in research dissemination, and striving for sustainability.ConclusionsAlthough the development of assessment tools in this field is in its infancy, our findings suggest that fidelity to CBPR processes can be assessed in a variety of settings

Plasma selenium concentration odds ratios for black and white Americans participating in the SCCS.

<p>SEPP1 - Selenoprotein P; GPX3 - Glutathione Peroxidase</p><p>†Quartile cutpoints were based on the distribution for each selenium (Se) plasma concentration with whites and blacks combined.</p><p>‡All models were adjusted for gender, age, education, household income, body mass index, smoking status, fruit and vegetable intake, meat and fish intake, and living on farm.</p

Comparison of plasma selenium concentration between the SCCS and NHANES III (1988–1994) participants.

<p>NHANES III: 40–79 yrs, South region of US.; BMI - Body Mass Index.</p

Mean difference by sociodemographic and lifestyle variables for selenium biomarkers among SCCS participants.

<p>BMI - Body Mass Index; SEPP1 - Selenoprotein P; GPX3 - Glutathione Peroxidase.</p