Adiposity and the perilipin gene: The role of single locus and multilocus variation, obesity-related quantitative traits, and disease-related phenotypes in the Atherosclerosis Risk in Communities (ARIC) study

Obesity is a complex multifactorial disease and is a public health priority. Perilipin coats the surface of lipid droplets in adipocytes and is believed to stabilize these lipid bodies by protecting triglyceride from early lipolysis. This research project evaluated the association between genetic variation within the human perilipin (PLIN) gene and obesity-related quantitative traits and disease-related phenotypes in Non-Hispanic White (NHW) and African American (AA) participants from the Atherosclerosis Risk in Communities (ARIC) Study. ^ Multivariate linear regression, multivariate logistic regression, and Cox proportional hazards models evaluated the association between single gene variants (rs2304794, rs894160, rs8179071, and rs2304795) and multilocus variation (rs894160 and rs2304795) within the PLIN gene and both obesity-related quantitative traits (body weight, body mass index [BMI], waist girth, waist-to-hip ratio [WHR], estimated percent body fat, and plasma total triglycerides) and disease-related phenotypes (prevalent obesity, metabolic syndrome [MetS], prevalent coronary heart disease [CHD], and incident CHD). Single variant analyses were stratified by race and gender within race while multilocus analyses were stratified by race. ^ Single variant analyses revealed that rs2304794 and rs894160 were significantly related to plasma triglyceride levels in all NHWs and NHW women. Among AA women, variant rs8179071 was associated with triglyceride levels and rs2304794 was associated with risk-raising waist circumference (>0.8 in women). The multilocus effects of variants rs894160 and rs2304795 were significantly associated with body weight, waist girth, WHR, estimated percent body fat, class II obesity (BMI ≥ 35 kg/m2), class III obesity (BMI ≥ 35 kg/m2), and risk-raising WHR (>0.9 in men and >0.8 in women) in AAs. Variant rs2304795 was significantly related to prevalent MetS among AA males and prevalent CHD in NHW women; multilocus effects of the PLIN gene were associated with prevalent CHD among NHWs. Rs2304794 was associated with incident CHD in the absence of the MetS among AAs. These findings support the hypothesis that variation within the PLIN gene influences obesity-related traits and disease-related phenotypes. ^ Understanding these effects of the PLIN genotype on the development of obesity can potentially lead to tailored health promotion interventions that are more effective. ^

Feeding practices and their associations with diarrhea incidence in a cohort of rural Egyptian infants

A study was conducted in 4 villages in Bilbeis, Egypt, to document the infant feeding practices and identify their determinants, and examine the associations between feeding practices and diarrhea incidence in infants. A cohort of 152 infants were followed from birth with twice-weekly home visits to record feeding practices and diarrheal illness. Cross-sectional information was obtained about child birth; early neonatal feeding practices; and the socioeconomic, demographic, and water and sanitation characteristics of study families.^ Prelacteal fees were given to 60% of the infants. Nineteen percent of the infants were wet nursed at least once during the first week of life. Breast-feeding prevalence declined from 100% among infants aged less than 12 weeks to 84% among those aged 44-47 weeks. The prevalence of exclusive breast-feeding among breast-fed infants was 38% in those aged less than 4 weeks, increased to 54% in age period 4-7 weeks, and then declined rapidly to 4% in age period 24-27 weeks. The patterns and determinants of consumption by breast-fed infants of specific supplements were examined in detail.^ Between birth and age 47 weeks, the diarrhea incidence rate per person-year among breast-fed infants (6.84 episodes) was identical to the rate among all infants (6.89 episodes). In age period 0-11 weeks, the diarrhea incidence rate among breast-fed infants receiving supplements was 1.3 times (95% confidence interval: 0.9-2.0) higher than the rate among those exclusively breast-fed. In other age periods, diarrhea incidence was generally nonsignificantly higher among exclusively breast-fed infants than among those partially breast-fed and those completely weaned.^ Both univariate and multivariate analyses were done to examine the associations between diarrhea incidence and the consumption by breast-fed infants of specific supplements. After multivariate adjustment, supplements that showed significant, borderline, or suggestive positive associations with diarrhea incidence were cereal-water, cheese, raw vegetables, and 'other' foods. Significant, borderline, or suggestive negative associations were observed between diarrhea incidence and the intake of fresh animal milk, and potatoes.^ To reduce the risk of diarrhea, indiscriminate use of supplements among Bilbeis infants aged less than 12 weeks should be strongly discouraged. While mothers in this area should be educated about methods of safer preparation, handling, storage, and administration of all weaning foods, their attention should be particularly drawn to the 4 foods that were found to be positively associated with diarrhea incidence among infants in this study. ^

The impact of a cooking and gardening summer camp experience on the fruit and vegetable consumption of elementary school-aged children

Childhood obesity is a significant public health problem. Over 15 percent of children in the United States are obese, and about 25 percent of children in Texas are overweight (CDC NHANES). Furthermore, about 30 percent of elementary school aged children in Harris County, Texas are overweight or obese (Children at Risk Institute 2010). In addition to actions such as increasing physical activity, decreasing television watching and video game time, decreasing snacking on low nutrient calorie dense foods and sugar sweetened beverages, children need to consume more fruits and vegetables. According to the National Health and Nutrition Examination Survey (NHANES) from 2002, about 26 percent of U.S. children are meeting the recommendations for daily fruit intake and about 16 percent are meeting the recommendations for daily vegetable intake (CDC NHANES). In 2004, the average total intake of vegetables was 0.9 cups per day and 1.1 cups of fruit per day by children ages four to nine years old in the U.S. (CDC NHANES). Not only do children need effective nutrition education to learn about fruits and vegetables, they also need access and repeated exposure to fruits and vegetables (Anderson 2009, Briefel 2009). Nutrition education interventions that provide a structured, hands-on curriculum such as school gardens have produced significant changes in child fruit and vegetable intake (Blair 2009, McAleese 2007). To prevent childhood obesity from continuing into adolescence and adulthood, effective nutrition education interventions need to be implemented immediately and for the long-term. However, research has shown short-term nutrition education interventions such as summer camps to be effective for significant changes in child fruit and vegetable intake, preferences, and knowledge (Heim 2009). ^ A four week summer camp based on cooking and gardening was implemented at 6 Multi-Service centers in a large, urban city. The participants included children ranging in age from 7 to 14 years old (n=64). The purpose of the camp was to introduce children to their food from the seed to the plate through the utilization of gardening and culinary exercises. The summer camp activities were aimed at increasing the children's exposure, willingness to try, preferences, knowledge, and intake of fruits and vegetables. A survey was given on the first day of camp and again on the last day of camp that measured the pre- and post differences in knowledge, intake, willingness to try, and preferences of fruits and vegetables. The present study examined the short-term effectiveness of a cooking and garden-based nutrition education program on the knowledge, willingness, preferences, and intake among children aged 8 to 13 years old (n=40). The final sample of participants (n=40) was controlled for those who completed pre- and post-test surveys and who were in or above the third grade level. Results showed a statistically significant increase in the reported intake of vegetables and preferences for vegetables, specifically green beans, and fruits. There was also a significant increase in preferences for fruits among boys and participants ages 11 to 13 years. The results showed a change in the expected direction of willingness to try, preferences for vegetables, and intake of fruit, however these were not statistically significant. Interestingly, the results also showed a decrease in the intake of low nutrient calorie dense foods such as sweets and candy.^

Development of a SPECT -based three-dimensional treatment planner for radionuclide therapy with iodine -131

Accurate calculation of absorbed dose to target tumors and normal tissues in the body is an important requirement for establishing fundamental dose-response relationships for radioimmunotherapy. Two major obstacles have been the difficulty in obtaining an accurate patient-specific 3-D activity map in-vivo and calculating the resulting absorbed dose. This study investigated a methodology for 3-D internal dosimetry, which integrates the 3-D biodistribution of the radionuclide acquired from SPECT with a dose-point kernel convolution technique to provide the 3-D distribution of absorbed dose. Accurate SPECT images were reconstructed with appropriate methods for noise filtering, attenuation correction, and Compton scatter correction. The SPECT images were converted into activity maps using a calibration phantom. The activity map was convolved with an $\sp{131}$I dose-point kernel using a 3-D fast Fourier transform to yield a 3-D distribution of absorbed dose. The 3-D absorbed dose map was then processed to provide the absorbed dose distribution in regions of interest. This methodology can provide heterogeneous distributions of absorbed dose in volumes of any size and shape with nonuniform distributions of activity. Comparison of the activities quantitated by our SPECT methodology to true activities in an Alderson abdominal phantom (with spleen, liver, and spherical tumor) yielded errors of $-$16.3% to 4.4%. Volume quantitation errors ranged from $-$4.0 to 5.9% for volumes greater than 88 ml. The percentage differences of the average absorbed dose rates calculated by this methodology and the MIRD S-values were 9.1% for liver, 13.7% for spleen, and 0.9% for the tumor. Good agreement (percent differences were less than 8%) was found between the absorbed dose due to penetrating radiation calculated from this methodology and TLD measurement. More accurate estimates of the 3-D distribution of absorbed dose can be used as a guide in specifying the minimum activity to be administered to patients to deliver a prescribed absorbed dose to tumor without exceeding the toxicity limits of normal tissues. ^