Links between the organization of the family home environment and child obesity: a systematic review.

Due to increasingly high rates of child overweight and obesity, it is important to identify risk and protective factors that may inform more effective prevention and intervention. The degree of organization in the family home environment is a studied, but not well-specified, factor that may impact child weight. Prior research on household organization has examined an array of constructs, including family routines, limit setting, household chaos, crowding and the broad home environment. This study systematically reviews literature on organization within the family home environment and weight among children ages 2-12. Six hundred thirty-seven studies were reviewed by four coders for eligibility, and 32 studies were included in the final synthesis. Overall, 84% of studies provided evidence for relations between at least one indicator of organization within the family home environment and child weight. Studies provided compelling evidence across several constructs, suggesting that the relevance of household organization to child weight extends beyond a single indicator. Directions for future work include (i) examining the mediating role of health behaviours, (ii) examining the moderating role of socioeconomic factors, (iii) broadening this evidence base across cultures and nationalities and (iv) integrating constructs to develop a comprehensive model of organization within the home environment.

Dietary calcium, calcium supplementation, and blood pressure in African American adolescents.

BACKGROUND: Intake of calcium from the diet is inversely associated with blood pressure in observational studies and animal models but randomized trials in humans have found only small effects of calcium supplementation on blood pressure. A blood pressure-lowering effect of calcium supplementation may thus be restricted to persons with a low intake of calcium from the diet and specific genetic or other characteristics. OBJECTIVE: A randomized trial was conducted to assess the effect of calcium supplementation on blood pressure in African American adolescents. Rapid growth during adolescence may increase calcium requirements, and avoidance of milk and milk products by some African Americans can result in low intake of calcium. DESIGN: One hundred sixteen adolescents (65 girls, 51 boys; mean age: 15.8 y) were given calcium (1.5 g/d) or placebo for 8 wk in a randomized, double-blind, crossover design. Blood pressure was measured after 2, 4, and 8 wk. Dietary calcium was determined with a validated food-frequency questionnaire. RESULTS: The net effect (+/-SE) of calcium supplementation on diastolic blood pressure was a reduction of 1.9 +/- 1.1 mm Hg (P = 0.04, one-tailed t test). Blood pressure reduction was greater in adolescents with lower intake of calcium from the diet (P = 0.003, one-tailed t test for interaction): -4.9 +/- 1.6, -2.3 +/- 1.6, and 1.4 +/- 1.8 mm Hg for change in the lower (0.024-0.067 g Ca/MJ), middle (0.069-0.091 g Ca/MJ), and upper (0.093-0.217 g Ca/MJ) tertiles, respectively. No main effect on systolic blood pressure was detected. CONCLUSION: These findings suggest that calcium supplementation may lower diastolic blood pressure in African American adolescents with low dietary intakes of calcium.

A novel mutation affecting the interdomain link region of the growth hormone receptor in a Vietnamese girl, and response to long-term treatment with recombinant human insulin-like growth factor-I and luteinizing hormone-releasing hormone analogue.

A Vietnamese girl with Laron syndrome has been treated with recombinant human insulin-like growth factor-I for 4 yr from age 11.28 yr. Her height SD score increased from -6.3 to -4.7 without acceleration of bone age. Isolated breast development progressed despite pubertal suppression with luteinizing hormone-releasing hormone analogue, which was stopped after 3 yr because of growth deceleration. Facial coarsening was documented with serial photographs. Sequencing and in vitro analysis identified a homozygous base pair substitution in exon 6 of the proband's GH receptor (GHR), which changed amino acid 131 from proline to glutamine (P131Q) and disrupted GH binding. Both the P131Q-mutated human GHR and wildtype (wt) hGHR were transiently expressed in COS-1 cells, as demonstrated by Western blotting, but the P131Q-transfected cells did not bind 125I-hGH. Similarly, FDC-P1 cells transfected with wthGHR bound 125I-hGH with high affinity and proliferated in response to GH, whereas the P131Q hGHR cells did neither. In CHO-K1 cells cotransfected with wthGHR and the Egr-1 promotor linked to a luciferase reporter gene, GH evoked a 2.14 +/- 0.21-fold increase in luciferase activity, but there was no response in the cells carrying the P131Q hGHR mutation. From examination of the crystal structure of the GHR, we suggest that the P131Q mutation disrupts the interdomain link between the extracellular domains of the GHR, causing a conformational change that results in disruption of the GH binding site.

Breath hydrogen excretion in healthy premature infants.

Breath hydrogen excretion during the neonatal period was studied on 84 occasions in 44 well premature infants of 27-37 weeks gestational age who all received lactose-containing feeds. Only one of 15 infants studied during the first 24 h excreted hydrogen. Thereafter, the proportion of infants excreting hydrogen increased daily. From day 5 onwards all the infants studied were found to be excreting hydrogen. The concentration and the volume of hydrogen exhaled by infants ranged from 10-230 parts/10(6) and 2.6-107 microL/min, respectively. Breath hydrogen excretion was variable and showed no relationship to birthweight, gestation period, volume of feed or the time of last feed through there was an increase with the age of the infant. Breath hydrogen excretion appears to be a normal phenomenon in premature infants and is probably related to gut colonization with lactose fermenting organisms.

Multidimensional liquid chromatography of opioid peptides: fluorogenic labelling, retention prediction and separation optimization.

The ultra-trace analysis of opioid peptides in biological samples can be achieved by multidimensional liquid chromatography with pre-column fluorogenic derivatization with naphthalene-2,3-dicarboxaldehyde in the presence of cyanide ion. However, in order to take full advantage of the high sensitivity possible with detectors based on laser-induced fluorescence or chemiluminescence, each component of the analytical method must be carefully optimized. In this study, strategies are presented for the prediction of retention time and the optimization of separations of derivatized opioid peptides in multidimensional LC systems.