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Introduction: Pentadecanoic (C15:0), heptadecanoic (C17:0) and trans-palmitoleic (t-C16:1n-7) fatty acids (FAs) are often used as biomarkers for dairy fat in adults. This study aimed to investigate the relationship between dairy product intake and these FAs in adolescents., Material and Methods: Healthy adolescents were randomized to one of three groups (Group 1: control; Group 2: consume 3 dairy servings/day; and Group 3: consume ≥ 4 servings/d). C15:0, C17:0 and t-C16:1n-7 were quantified using gas chromatography. Dietary intakes were assessed by 24 h diet recalls., Results: No difference was observed in FAs at baseline or 6 months (mo), however, at 12 mo, erythrocyte C15:0 increased in group 3 (+0.37 µg/ml, p = 0.01). Dairy intake increased in both intervention groups (Group 2: +1.4 servings/d; Group 3: +2.4 servings/d, p < 0.0001) and positively correlated with erythrocyte C15:0 at 12 mo., Conclusion: Erythrocyte FAs appear to be associated with increasing dairy intakes during adolescence., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

In forest ecosystems, litter quality is a major driver for soil and understorey characteristics, but elevation, microtopography and subsoil properties may also be important. We tested the importance of each factor in two ancient mixed forests on decalcified marl, dominated by trees with different litter quality such as European hornbeam, with high-palatable litter, and beech, with low-palatable litter. We mapped elevation, differences in local height (microtopography), tree distribution and understorey cover on slopes ranging from crest to bottom, and sampled 200 7 × 7 m grid cells for characteristics of litter input, understorey, topsoil and subsoil. In both forests, elevation decreased gradually, but microtopography showed irregular patterns of depressions and mounds of a few cm below or above average local height. Tree distribution was not affected by elevation or subsoil properties, but clearly by microtopography. Adult beech was abundant on local mounds, while hornbeam was more common in local depressions. Topsoil and understorey characteristics were mainly affected by litter quality (tree species dominance) and microtopography. Litter quality had separate effects from microtopography, but could reinforce this. High litter quality (hornbeam) and low local height both led to high earthworm activity, low litter mass, high erosion, impermeable clay layers close to the surface, high pH, high soil moisture and high diversity of the understorey. Low litter quality (beech) and high local height both led to low earthworm activity, high litter mass, low erosion, low pH, low soil moisture and low plant diversity. Beech and hornbeam may act as ecosystem engineers, which change habitat conditions and local hydrology, and make habitats more suitable to themselves, and/or unsuitable to the other. However, they also increased spatial complexity of the forest and length of the habitat gradient. This may increase forest biodiversity as a whole, but also resilience to prolonged wet or dry periods., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Background/objectives: Infant complementary feeding is important for establishing food preferences. Few studies exist on the effects of infant complementary feeding choices (food preparation methods) on dietary intake, growth or adiposity. We examined whether provision of homemade complementary food is associated with the development of dietary diversity, nutrient intakes and quality of infant growth., Subjects/methods: Secondary analysis of feeding practices from a randomized trial of vitamin D supplementation in 132 healthy breastfed 1-month-old infants from Montréal, Canada. This longitudinal study used diet records, anthropometric and body composition data (dual-energy X-ray absorptiometry) from assessments that occurred when infants were 6, 9, 12 and 36 months of age. Infants were grouped into three categories of food preparation method on the basis of whether or not they had consumed homemade or commercial meat or fruit and vegetable by 9 months (homemade, commercial and both). Multivariable regression controlled for family income, maternal education and infant sex., Results: Dietary data were available for 65 infants. By 9 months, 22% of infants had exclusively received homemade (n=14), 14 infants had exclusively received commercial and 37 infants had received both. The development of dietary diversity (number of World Health Organization-recommended food groups) was higher (0.76 (95% confidence interval (CI): 0.14, 1.38); P<0.05) in the homemade group versus commercial. Energy and nutrient intakes did not differ by group over time. The homemade group had 773 g (-1364, -182; P<0.01) lower whole-body fat mass and 7.1% (-12.6, -1.6; P<0.05) lower % body fat at 12 months compared with the reference group (both homemade and commercial). Reduced whole-body fat mass in the homemade group persisted at 36 months (-696 g (95% CI: -1341, -52); P<0.05). There were no differences between groups for changes in growth Z-scores (length-for-age, weight-for-age and body mass index-for-age)., Conclusions: Provision of homemade complementary food is associated with increased dietary diversity during the first year of life and reduced adiposity.

The prevalence of excess weight in children and adults worldwide has increased rapidly in the last 25 years. Obesity is positively associated with increased risk for many health issues such as type 2 diabetes, cardiovascular disease and psychosocial problems. This review focuses on child populations, as it is known that the sedentary behaviors of overweight/obese youth often endure into adulthood. Assessment of physical activity (PA), among other factors such as diet and socio-economic status, is important in understanding weight variation and in designing interventions. This review highlights common subjective and objective PA assessment tools, the validity of these methods and acceptable ways of collecting and interpreting PA data. The aim is to provide an update on PA assessment in overweight/obese children, highlighting current knowledge and any gaps in the literature, in order to facilitate the use of PA assessments and interventions by health-care professionals as well as suggest future research in this area.

Flaxseed's oil and lignan, secoisolariciresinol diglucoside (SDG), are implicated in attainment of health and treatment of renal injury and osteoporosis. To test for these benefits, weanling Han:SPRD-cy rats (n=171) with or without kidney disease were randomized to diets made with either corn oil or flaxseed oil and with or without SDG for 12 weeks. In females, weight was lower with the SDG diet. In males fed flaxseed oil, lean mass was higher and fat % was lower. In both sexes, fat % was lower in diseased rats. Bone mineral content (BMC) and density were higher in rats fed flaxseed oil and lower in diseased rats, additionally; BMC was lower in SDG-supplemented females. The benefit of flaxseed oil on body composition is sex specific but the effect on bone mass is not. Lastly, reduced weight due to early rat kidney disease is not due to loss of lean body mass.

Background: Preterm infants are at risk for suboptimal growth and bone mineralization compared to infants born at term but long-term outcomes into early adulthood are unclear., Aims: To determine (1) if growth and nutrition in the first year of life significantly predict the outcomes measured at adulthood and (2) whole body and regional bone mineral content (BMC) of young adults who were born preterm and weighing <1500 g., Study Design and Subjects: In this descriptive follow-up study, subjects were born preterm and weighing <1500 g (n=25, 17.2+/-1.2 years of age) and originally participated in a 1-year follow-up study of infant growth or subjects born at term (n=25, 17.3+/-1.4 years of age)., Outcome Measures: In the preterm group, relationships of growth and nutrition in the first year of life with adult anthropometry and BMC were identified using correlation and regression analysis. Birth groups were compared for measurements of anthropometry and whole body and regional BMC obtained at adulthood using t-tests., Results: After correcting for the effects of bone area using regression, rate of weight gain had a positive relationship and days to regain birth weight a negative relationship to adult BMC. Young adults, born preterm, were significantly shorter with lower whole body BMC than of those born at term, but BMC was appropriate for size., Conclusions: Growth early in life predicts subsequent attainment of growth and bone mass. Premature birth results in lower attainment of height achieved by young adult age but bone mass is appropriate for body size.

Essential fatty acids are fundamental to normal growth and development, but North American formulas do not contain arachidonic (AA) and docosahexaenoic acid (DHA). The main objective of the present study was to determine whether addition of AA and DHA to formula elevates growth and bone mineralization in piglets. A secondary objective was to establish whether liver fatty acid composition is related to that of bone. Twelve 10-d-old male piglets were randomized to receive either a standard formula with an n-6:n-3 fatty acid ratio of 4.9:1.0 or the same formula made with an equal amount of fat but containing AA (0.5% wt/wt total fat) and DHA (0.1% wt/wt total fat) for 14 d. Piglets in the supplemented group had significantly (p < 0.05) higher weight and greater bone mineral density of the whole body, lumbar spine, and femur. No differences were observed in whole body length, calcium absorption, or biochemical markers of bone metabolism. Feeding AA resulted in lower linoleic acid (p < 0.05) and higher (p < 0.05) AA in liver total lipid (% wt/wt) and bone FFA (% wt/wt) but no change to DHA. Liver AA (% wt/wt total lipid) was positively related (p < 0.05) to growth, free AA (% wt/wt) in bone, bone mineral content, bone mineral density, and urinary prostaglandin E2 but negatively related (p < 0.05) to free linoleic acid in bone. Inverse relationships were observed when liver linoleic acid was substituted for liver AA as the independent variable. These data indicate that feeding AA is associated with elevated weight and higher whole body and regional bone mineral density.

Unlabelled: Modification of polycystic kidney disease and fatty acid status by soy protein diet., Background: Previous studies have demonstrated that soy protein can slow progression of renal injury in the Han:SPRD-cy rat. We undertook a study to establish whether this benefit was independent of any nutritional deprivation, and whether or not it was associated with changes in polyunsaturated fatty acid status that have been previously linked to the anti-inflammatory or antineoplastic potential of soy diets., Methods: Male Han:SPRD-cy rats were pair fed a 20% casein or 20% soy protein diet for six weeks from weaning. Tissue was harvested for analysis of cystic change, cell proliferation, macrophage infiltration, and fibrosis. Renal and hepatic tissues were also harvested for lipid analysis using gas chromatography., Results: Animals thrived on both diets. Soy protein feeding was associated with reduced cystic change (4.3 vs. 7.0 mL/kg, P < 0.0001), epithelial cell proliferation (15.7 vs. 21.0 cells/mm epithelium, P < 0.0001), macrophage infiltration (25.3 vs. 43.5 cells/high-power field, P < 0.0001), and fibrosis (0.6 vs. 1.07 mL/kg, P < 0.0001). The soy diet prevented a significant elevation in serum creatinine in diseased versus normal animals. Soy feeding was associated with higher renal and hepatic linoleic acid content and higher hepatic alpha-linolenic acid, but lower hepatic arachidonic acid content., Conclusions: Isocaloric soy protein feeding ameliorates both epithelial and interstitial changes in the Han:SPRD-cy rat independent of a hypocholesterolemic effect. The histologic benefit is associated with changes in polyunsaturated fatty acid metabolism that may influence both inflammatory and proliferative pathways.

Previously, we conducted dual energy x-ray absorptiometry (DXA) (Hologic QDR-1000/W) scans and carcass analysis of piglets to evaluate the Pediatric Whole Body software (PedWB) (V5.35) for use in infants. A software upgrade designed for infant whole body (InfWB) (V5.56) led to a reassessment of DXA by: 1) reanalysis of the original scans using InfWB software and 2) comparison of InfWB-estimates of bone mineral content (BMC) and lean and fat mass with chemical analysis. Other assessments included 1) methods of regional analysis and 2) artifacts and the Infant Table Pad in the scan field. The mean coefficients of variation for InfWB whole body measures in small piglets (n = 10, weight 1575 +/- 73 g) and large piglets (n = 10, weight 5894 +/- 208 g) were less than 2.6% except for fat mass which was higher (8.0% versus 6.3% and 6.6% versus 3.5%, respectively) compared with PedWB. In large piglets InfWB produced good estimates of BMC, lean and fat masses. In small piglets, fat mass by InfWB was correlated with chemical analysis, but not by PedWB. There was improvement in the estimation of BMC with InfWB, from 27 +/- 2.2 g to 32 +/- 2.3 g (carcass ash = 38 +/- 3.3 g). Femur BMC analysis by InfWB was precise and was accurate when compared with chemical analysis. Artifacts in the DXA scan field (diapers and blankets) resulted in an increase of the DXA-estimated fat and lean masses. The Infant Table Pad increased the estimate of fat mass in a small piglet by 50%, thus further study is required before it is used routinely. Improvements of the DXA technology have resulted in a more accurate tool, if scanning procedures are carefully implemented.

The objective of this study was to assess the effect of dexamethasone on growth, body composition and protein metabolism using the piglet as a model for rapidly growing premature infants. Seven-day-old male pigs (n = 18) were randomized to 0.5 mg/kg/day oral dexamethasone or placebo for 15 consecutive days. Weight and length gains and weight gained per energy or protein consumed were significantly lower in the dexamethasone group. Serum urea nitrogen was significantly higher in the dexamethasone group by day 15 of the study. No differences were observed between groups for urinary creatinine. The whole body percent lean mass was significantly lower and percent fat mass was significantly higher in the dexamethasone piglets, as measured by dual energy X-ray absorptiometry. In young piglets, dexamethasone, at doses similar to those in premature infants, induces protein catabolism, impairs growth and alters its composition.

Calcium and vitamin D metabolism, bone mineralization, and growth were studied in piglets randomly assigned to 15 d of dexamethasone (0.5 mg.kg-1.d-1, orally) or placebo. Growth velocity was significantly reduced by dexamethasone treatment (P < 0.001). Pigs in the dexamethasone group demonstrated lower 45Ca absorption by in situ intestinal perfusion (P < 0.01). Plasma 25-hydroxycholecalciferol (calcidiol) and 1,25-dihydroxycholecalciferol (calcitriol) were lower (P < 0.05) and the urinary ratio of calcium to creatinine was higher (P < 0.05) after 15 d of dexamethasone compared with placebo. Differences between pre- and postosteocalcin (P < 0.01) and pyridinoline (P < 0.01) were higher and wholebody, lumbar, and femur bone mineral density were lower (P < 0.05) in dexamethasone-treated piglets. Dexamethasone-induced reductions in bone mineral mass likely result from reduced vitamin D status, reduced intestinal calcium absorption, elevated urinary calcium loss and direct effects of the steroid on bone. When dexamethasone is used in premature infants to improve lung function, negative effects on growth and bone metabolism could occur.