The biological activity of two fluorinated analogs of 1,25(OH)2D3 was compared with 1,25(OH)2D3 in various vitamin D assays. The effect of 24,24-F2-1,25(OH)2D3 on plasma calcium, bone weight and duodenal calcium binding protein in chicken, on calcium excretion via egg shell in Japanese quails and on mobilization of calcium from the bone in rats was twice as high as the effect of the most potent naturally occurring vitamin D3 metabolite 1,25(OH)2D3. In contrast, 24R-F-1,25(OH)2D3 has less than 50% of the potency of 1,25(OH)2D3. Due to the wider therapeutic dosage range, this compound might be of clinical value.
We measured body weight, height, and skinfold thickness (SFT) at ulnar, triceps, subscapular and suprailiac regions in 1,656 Japanese children aged 3-11 years. Means of SFT in boys and girls with normal weight exhibited similar changes with age to Caucasian children. However, nadirs of SFT were observed 1 year earlier and means at 11 years were slightly higher in Japanese. Correlation coefficients between SFT and excess weight (EW) were high in boys and girls when EW was more than 10%. Some children with EW of more than 10% had abnormal SFT. Skinfolds in all children with EW of 30% or more were beyond the normal limits. In this study, normal ranges of SFT in Japanese children are demonstrated and their racial characteristics are compared to Caucasians. It is suggested that children with EW of 10-30% are heterogenous and determination of fat volume is essential to confirm the diagnosis of obesity in these subjects.
Validity and reproducibility were evaluated of a new questionnaire to assess fruit and vegetable intakes in 11- to 12-year-old children.
The precoded teacher-assisted self-administered questionnaire included two sections: a 24-hour recall part and a food frequency part. Validity was tested in 4 countries (Denmark, Iceland, Norway, Portugal; n = 43-60 per country) using a 1-day weighed food record and 7-day food records as reference methods. Test-retest (7-12 days apart) reproducibility was assessed in 6 countries (Belgium, Denmark, Iceland, Norway, Portugal, Spain; n = 60-74 per country).
Spearman rank correlations for fruit and vegetable intake according to the frequency part and the 7-day food record ranged between r = 0.40-0.53. Between 25-50% were classified into the same quartile and 70-88% into the same or adjacent quartile. Test-retest Spearman rank correlations for the food frequency part were r = 0.47-0.84. Three countries showed no significant difference between fruit intake as assessed with the 24-hour recall part and the 1-day weighed food record, and 2 countries showed no significant difference for vegetables. In the other countries, the 24-hour recall part resulted in substantially higher mean intake levels.
Validity and reproducibility as to ranking of subjects were regarded to be satisfactory in all countries. Group mean intake, based on the original 24-hour part, was valid for fruit in 3 countries and for vegetables in 2 countries, and this part was subsequently adjusted to avoid overestimation, before the questionnaire was used in the Pro Children study.
For the development of fruit and vegetable promotion interventions, insight is needed into determinants of health behaviour. This study presents results of focus group interviews held with 10- to 11-year-old schoolchildren from Ghent (Belgium-Flanders) and Rotterdam (the Netherlands) to explore personal beliefs and motivations and environmental factors related to schoolchildren's fruit and vegetable intake, to inform the Pro Children intervention development.
Twelve focus groups were held with 92 schoolchildren. The interviews were recorded and transcribed and NVivo was used to analyse the transcripts.
Positive health beliefs, taste preferences, lack of knowledge and practical barriers were identified as personal factors related to fruit and vegetable intake. Home and school availability of fruits and vegetables, as well as parenting practices were identified as important environmental factors.
A fruit and vegetable promotion intervention should aim to increase fruit and vegetable accessibility and should include educational and motivational activities tailored to these personal and environmental factors. These indications should be further evaluated in quantitative research among representative samples.
Background/aims:
The prevalence of overweight and obesity in childhood is increasing markedly. The aim of this study was to evaluate the relationship between physical activity, energy consumption and weight status in a cohort of Spanish children.
Methods:
A total of 137 children (11-13 years old) participated in the study voluntarily (with paternal consent). Children were classified into 3 groups according to their physical activity, i.e. sedentary, active and sporty groups. Body composition measures, physical fitness and total caloric and macronutrient intake were determined.
Results:
Weight, body mass index, waist circumference, skinfold thickness measures and body fat percentage of children were lower in the active children, whereas body water content increased with activity. Nutritional habits were similar in the 3 studied groups. No significant differences in total energy intake or percentage of carbohydrates, fat and proteins were found. All parameters related to caloric expenditure were higher in children carrying out more physical activity.
Conclusions:
Children with higher levels of physical activity presented more favorable anthropometric profiles, but there were no differences in respect to their dietary habits. An increase in weekly energy expenditure through physical activity outside school seems essential to prevent overweight and the risk of childhood obesity.
All-trans-[11-3H]retinyl acetate was injected directly into the testes of young rats and testicular and liver metabolites were analyzed by HPLC at 6, 24 and 72 h post injection. All-trans-retinyl acetate was hydrolyzed to retinol and further metabolized to polar compounds and a trace of retinoic acid, or reesterified to various retinyl esters including retinyl palmitate and retinyl stearate. Thus, retinyl ester hydrolyzing and esterifying enzymes are present in the testes of young rats. Eleven, twelve and ten radioactive peaks were observed at 6, 24 and 72 h, respectively. The amount of radioactivity in retinyl palmitate and retinyl stearate increased with time and reached 24 and 4%, respectively, by 72 h. Although retinol predominated, retinyl palmitate was the major esterified form in testis. The amount of radioactivity in retinol and retinyl acetate decreased with time and increased in unidentified metabolites and retinyl esters. An insignificant amount of radioactivity was found in liver. We conclude from these results that some vitamin A is stored/accumulated in the testes as retinyl esters in order to support the process of spermatogenesis and other physiological functions and that the retinol esterifying enzyme is quite active in the testes of young rats.
An adequate fruit and vegetable intake provides essential nutrients and nutritive compounds and is considered an important part of a healthy lifestyle. No simple instrument has been available for the assessment of fruit and vegetable intake as well as its determinants in school-aged children applicable in different European countries. Within the Pro Children Project, such an instrument has been developed. This paper describes the cross-sectional survey in 11-year-olds in 9 countries.
The cross-sectional survey used nationally, and in 2 countries regionally, representative samples of schools and classes. The questionnaires, including a precoded 24-hour recall component and a food frequency part, were completed in the classroom. Data were treated using common syntax files for portion sizes and for merging of vegetable types into four subgroups.
The results show that the fruit and vegetable intake in amounts and choice were highly diverse in the 9 participating countries. Vegetable intake was in general lower than fruit intake, boys consumed less fruit and vegetables than girls did. The highest total intake according to the 24-hour recall was found in Austria and Portugal, the lowest in Spain and Iceland.
The fruit and vegetable intake in 11-year-old children was in all countries far from reaching population goals and food-based dietary guidelines on national and international levels.
Many epidemiologic studies have reported a link between calcium (Ca) deficiency and metabolic syndrome. In this study, we examine Ca deficiency in rats and whether changes in glucocorticoid metabolism are induced.
Twelve-week-old female Wistar rats were weaned onto a very-low-Ca diet (low-Ca group) or a control diet (control group) for 2 weeks. Quantitative real-time PCR was used to assess mRNA for 11β-hydroxysteroid dehydrogenase-1 (11β-HSD1), 11β-HSD2, phosphoenolpyruvate carboxykinase, peroxisome proliferator-activated receptor-α, and glucocorticoid receptor in the liver. Concentrations of adiponectin, leptin, corticosterone, intact parathyroid hormone, asymmetrical dimethylarginine and insulin in fasting serum were determined using a rat-specific enzyme-linked immunosorbent assay. Glucose concentrations were measured using a glucose oxidase system. Serum ionized Ca levels were measured with an automatic ion-selective electrode analyzer. Serum nitrite/nitrate levels were measured using a colorimetric assay kit.
After 2 weeks, no differences in serum glucose, corticosterone or insulin levels were observed. The low-Ca group rats showed higher homeostasis model assessment insulin resistance, lower adiponectin and higher intact parathyroid hormone levels. Serum nitrite/nitrate and asymmetrical dimethylarginine were significantly higher in the low-Ca group than in the control group. The expression of hepatic 11β-HSD1 mRNA was upregulated, while hepatic phosphoenolpyruvate carboxykinase expression was downregulated in the low-Ca group. Glucocorticoid receptor, peroxisome proliferator-activated receptor-α and 11β-HSD2 expression levels showed a similar tendency.
A low-Ca diet alters glucocorticoid metabolism, which leads to hepatic upregulation of 11β-HSD1, and is possibly a key mechanism inducing the metabolic complications of Ca deficiency.
To describe and compare fruit and vegetable intakes of mothers of 11-year-old children across Europe.
Cross-sectional surveys were carried out in 9 European countries in October/November 2003. Self-administered questionnaires assessing fruit and vegetable consumption were used for data collection. The current paper presents dietary intake data obtained by a precoded 24-hour recall and a food frequency questionnaire.
The consumption levels of fruit and vegetables (without fruit juice) were in line with World Health Organization recommendations of > or =400 g/day for only 27% of all participating mothers. Based on both instruments, the Pro Children results showed comparatively high average fruit intake levels in Portugal, Denmark and Sweden (211, 203 and 194 g/day) and the lowest intake in Iceland (97 g/day). High vegetable intake levels were found in Portugal and Belgium (169 and 150 g/day), the lowest in Spain (88 g/day). A south-north gradient could not be observed in the Pro Children study.
Fruit and vegetable intakes are low in mothers of 11-year-olds across Europe. Especially vegetable consumption can be regarded as marginal in most of the studied European countries. A high percentage of mothers indicated to eat fruit and vegetables less than once a day. The results have shown that national and international interventions are necessary to promote fruit and especially vegetable consumption in the European population of mothers.
To compare the consumption of the cow milk proteins A1 and B beta-casein among children and adolescents in Iceland and Scandinavia (Norway, Denmark, Sweden and Finland) as this might explain the lower incidence of type 1 diabetes (per 100,000/year, 0-14 years) in Iceland.
The consumption of A1 beta-casein in each country among 2- and 11- to 14-year-old children was calculated from results on food intake and on cow milk protein concentration. The consumption values were then compared and evaluated against the incidence of type 1 diabetes.
There was a significant difference between the consumption of A1 (p = 0.034) as well as the sum of A1 and B (p = 0.021) beta-casein in Iceland and Scandinavia for 2-year-old children. In the same age group, consumption of A1 beta-casein correlated with the incidence of type 1 diabetes in the countries (r = 0.9; p = 0.037). No significant difference in consumption of A1 or the sum of A1 and B beta-casein was found for 11- to 14-year-old adolescents.
This study supports that lower consumption of A1 beta-casein might be related to the lower incidence of type 1 diabetes in Iceland than in Scandinavia. Additionally it indicates that consumption in young childhood might be of more importance for the development of the disease incidence than consumption in adolescence.
Nutritional status was assessed in 300 geriatric patients aged 75 years or more using clinical, anthropometric, biochemical and immunologic methods. Relations between different assessment methods and their prognostic significance with regard to 18-month mortality were examined. For biochemical variables 10% (prealbumin, vitamin B6) to 37% (vitamins A and C) were below conventional limits. In 44% of the patients lymphocytes were diminished. 44% were anergic. Judgement of nutritional status by clinical impression resulted in 22% being deemed undernourished. Clinical diagnosis of undernutrition was associated with low anthropometric measurements (p less than 0.05 for all parameters) and a high prevalence of low biochemical values (p less than 0.05 for albumin, prealbumin, transferrin, vitamin A, vitamin B1). The mean values of all anthropometric variables, plasma proteins, vitamins A and C were significantly lower in patients who died within the following 18 months compared to survivors. The greatest prognostic significance was related to the clinical diagnosis of malnutrition. We conclude that clinical assessment is useful for the evaluation of nutritional status in geriatric patients and the best of numerous nutritional parameters to estimate risk of long-term mortality.
Changes in lipid profiles have been shown to be associated with diet and apolipoprotein (APO) polymorphisms. Therefore, 2 polymorphisms, i.e. APOA5-1131T>C and APOC3-482C>T, and serum lipids were examined in a Chinese healthy young population with high-carbohydrate/low-fat (HC/LF) diet intervention.
After a wash-out diet for 7 days, 56 young adults (22.89 ± 1.80 years) received the HC/LF diet for 6 days. Body mass index (BMI) and fasting serum lipid profiles at baseline, after the wash-out diet, and after the HC/LF diet were measured.
APOA5-1131C carriers had higher triglyceride (TG) and TG-rich lipoprotein TG (TRL-TG) levels at baseline and after the HC/LF diet, though this mainly corresponded to the female cohort. APOC3-482T carriers had higher TRL-TG levels following the wash-out and HC/LF diets, but these were not directly attributable to a single gender.
Both polymorphisms may play an important role in the elevated TG and TRL-TG levels induced by the HC/LF diet, especially in females, thus indicating a potential dietary prevention of coronary heart disease in this Chinese cohort.
Background:
C4 plants (e.g. corn and sugar cane) have greater (13)C enrichment than C3 plants (e.g. wheat and sugar beet).
Objective:
To assess whether (13)C enrichment of CO2 in the breath and breast milk of women on diets based on C3 and C4 foods changes from one diet to the other.
Materials and methods:
Six breast-feeding women were studied at 5-6 months postpartum. They ate a controlled C4 diet on days 1 and 2 followed by a C3 diet on days 3 and 4. Diet duplicates, breast milk on days 2 and 4 and hourly breath samples were collected over 4 days. (13)C enrichment was measured by isotope-ratio mass spectrometry. Values of δ(13)C were calculated from the international PDBV standard (δ(13)CPDBV). Differences between means were compared by paired t test or t test for repeated measurements.
Results:
δ(13)CPDBV values were significantly higher in the C4 diet than in the C3 diet composites (p < 0.01). In breath CO2, the δ(13)CPDBV value was greater on days 1 and 2 (range -15.4 to -13.2, respectively) and declined on days 3 and 4 (range -20.0 to -21.8, respectively, p < 0.01). The lipid and milk serum fractions of breast milk had significantly higher δ(13)CPDBV on the C3 diet than on the C4 diet (p < 0.01).
Conclusions:
Subjects eating a C4 diet have a higher δ(13)CPDBV value in the breath and breast milk fractions, which diminish rapidly on a C3 diet. Further studies focusing on individual nutrients are warranted.
Using gas chromatography-isotope ratio mass spectrometry, the detection, with a good reproducibility and in a single step, of the 13C content of glycoprotein neutral sugars, glycogen glucose, and ribonucleic acid ribose allowed us to trace incorporation into intestinal macromolecules of sugars derived from dietary glucose, labeled either naturally (as corn starch) or artificially. The 13C enrichment of glycoprotein neutral sugars was strong and rapid and plateaued up to the end of the experiment, whereas the 13C content of ribose increased linearly with time. By contrast, with artificially enriched dietary glucose, no significant 13C enrichment was detected in glycogen, suggesting that this macromolecule does not directly derive from dietary glucose. These results suggest differential control of sugars involved in the synthesis of intestinal macromolecules and demonstrate that this technique would be sensitive and reliable enough to be applied in man for serum glycoprotein sugar determinations.
Body weight and height of Japanese boys and girls aged 12-14 years were measured to calculate the prevalence of obesity, leanness and anorexia nervosa. In boys, the prevalence of obesity as well as leanness was significantly higher in the areas where population density was lower and among the boys who attended schools with smaller numbers of pupils. In the girls, these findings were similar to the boys. On the other hand, anorexia nervosa was found in girls only more commonly in the areas with higher population density and in the larger schools. These results suggest that higher prevalence of obesity in certain subjects may be associated with increased numbers of leanness but not with anorexia nervosa.
This study was carried out with three groups of weanling rats. One group was fed a high-protein (20%) diet, another group a low-protein (2.5%) diet, the third group a high-protein diet in restricted amounts. After 4 weeks of feeding, rats were injected simultaneously with L-[G-3H]-tryptophan and [carboxyl-14C]-nicotinic acid. The ratio of incorporation of [3H]-tryptophan to that of [14C]-nicotinic acid into liver NAD and NADP was found to be higher in protein-restricted rats. On the other hand, the ratio was found to be reduced in diet-restricted group of rats compared with ad libitum fed or low-protein diet fed groups. These results suggest that the efficiency of conversion of tryptophan to NAD is increased in protein deficiency, but reduced in the diet restriction. These observations are in line with our earlier findings on the changes in liver quinolinate phosphoribosyltransferase (EC 2.4.2.19) activity following feeding of low-protein or restricted diets. It is suggested that this technique of measuring the incorporation of two isotopes from the substrates labelled with two different isotopes can be conveniently used as a tool to measure the relative contribution of tryptophan and nicotinic acid to the synthesis of nicotinamide nucleotides.
The present study investigates the metabolic disposition of octacosanol in liver and muscle of rats after serial doses administration. Three groups of experimental animals received various doses of (8-14C)-octacosanol (2.0 microCi/dose) orally through a stomach tube. When expressed per organ, the highest amount of radioactivity was found in the liver (9.5% of administered dose), followed by the digestive tracts (8.2%) and the muscle (3.5%) at all doses of administration. The radioactivity in all other tissues examined was insignificant (< 0.9% in each) at any time during this period. The radioactivity in liver disappeared rapidly after 2-dose administration, even when the doses were increased. In contrast, the muscle seemed to be able to store a considerable amount of octacosanol in response to doses of administration. In case of 9-dose serial administration, after 3 and 9 days the accumulation of radioactivity in muscle was higher than that of the liver, possibly due to slow elimination of radioactivity from muscle. By the time when radioactivity in liver and muscle was low (after 6 and 10 doses), the radioactivity of octacosanol in plasma reached a maximum, particularly after administration of 6 doses. The plasma concentration and the fecal excretion of the radioactivity of octacosanol reached a maximum at the third day after the oral 6 doses, which reflected not only the saturation of radioactivity uptake by liver and muscle but also the metabolism and excretion of octacosanol with time at the same period. The results are discussed in the light of the role of octacosanol in increasing muscle endurance in exercise.
Analysis of the respiratory 14CO2 of growing chicks injected intraperitoneally with [1-14C] or [U-14C]glycine or valine has shown the presence of a delayed 'slow 14CO2' exponential component. The half-lives, about 3 h, are independent of the nature of the amino acid and of the age (1-3 weeks) of the animal. As supported by investigations in cycloheximide-treated chicks of the oxidative catabolism of glycine, valine and acetate, slow 14CO2 is significantly associated with the degradation of short-lived proteins.
6-day-old suckling rats, born to females kept on a fat-free diet, were used to determine cholesterol and fatty acid specific radioactivity (SRA) in the liver, kidneys and brain, after injection of 3 microCi uniformly 14C-labeled linoleic acid (ULI) or oleic acid (UOL). 1 h after injection, cholesterol SRA was highest in the liver and kidneys, and then decreased when UOL was injected. Cholesterol SRA peaked 3 h after injection of ULI in liver and kidneys. The delay in appearance of the ULI (over UOL) peak of cholesterol SRA may be due to differences in the rates of oxidation of these two labeled fatty acids into acetyl-CoA ester, according to the structural role of ULI. In the period between 3 and 56 h, cholesterol was more radioactive in the three tissues after injection of ULI than after injection of UOL. The radioactivity of saturated fatty acids was low in the ULI and UOL groups of these very young animals. Therefore, cholesterol synthesis seemed to happen at a faster rate than the other lipid syntheses in liver and kidneys, where the rate of linoleic acid elongation into arachidonic acid was also slower than cholesterol synthesis. Different results were obtained in the brain, where arachidonic acid SRA increased rapidly after ULI injection.
The uptake and distribution in rats of the radiolabelled dipeptide L-alanyl-L-[U-14C]glutamine were investigated by whole-body autoradiography. Rats were killed 5, 30 and 180 min following bolus injection of the peptide via the tail vein and, as a comparison, 180 min after injection of [U-14C]glutamine; 30-microns sections of the animals were autoradiographed against an X-ray film. Tissue specimens from the remainder of the carcass were completely combusted and the 14CO2 formed was analyzed by liquid scintillation counting. Visceral organs especially exocrine glands and the mucosa of the alimentary tract showed an initially high labelling (5 min), whereas skeletal muscle and brain exhibited maximum radioactivity 30 min after peptide bolus. Muscle and intestine (19 and 10% of the dose injected, respectively) showed the highest 14C incorporation of all tissues investigated. The broad conformity in 14C distribution observed after peptide and glutamine bolus strongly indicates similar utilization of free and peptide-bound glutamine.
A single dose of [1-14C] or [U-14C]glycine or L-[1-14C] or [U-14C]valine was injected intraperitoneally into 1- and 3-week-old chicks. Continuous automatic determination of respiratory 14CO2 and determination of 14C in excreta and uric acid were carried out for 8 h. Computer-aided analysis of the kinetics of respiratory 14CO2 demonstrated two exponentially decreasing components, 'fast 14CO2' and slow 14CO2'. Fast 14CO2 production represents the immediate oxidation and/or decarboxylation of the 14C-labeled amino acid. The half-lives differed according to the nature of the 14C-labeled amino acid but not to the age of the chick. The size of the acetyl-CoA pool labeled by [14C]glycine was between 10 and 15 mmol/100 g of chick. Metabolic partition of a circulating plasma free amino acid between oxidation and retention could be quantified by an isotopic index.
Young rats fed a diet providing 0.3, 3 or 10% of the energy as essential fatty acids (EFA) were given a single intravenous dose of albumin-bound 1-14C-linoleic acid. 1 animal from each group was killed at 1 and 18 h, respectively, after the injection and submitted to whole-body autoradiography. In general, the activities in the tissues were higher in the 0.3% group than in the other groups, whereas the differences between the 3% and the 10% group were small. In all groups the highest activity occurred in the brown fat. High activities were also noted in the liver, the adrenal cortex, the diaphragm, and the gastric and intestinal mucosa. The higher activities in the tissues of the rats fed 0.3% than in the tissues of those fed 3% or 10% EFA probably reflect a higher incorporation of fatty acids of the linoleic acid series into structural and other lipids in the former group due to the lack of EFA.
N digestibility and the dietary quality of a Vicia faba protein isolate as well as of two protein fractions from this isolate, acetylated and nonacetylated, were estimated in 15N-labelled adult rats. For reference, whole egg, casein and wheat were studied. The diets were fed at maintenance energy intake level. Daily metabolic fecal nitrogen estimated by an isotopic method was 5 mg/100 g body weight in animals receiving whole egg, casein, or Vicia faba proteins. When wheat was included in the diet metabolic fecal nitrogen was increased to 140% of this value. True N digestibility of reference proteins was 91-92% and of Vicia faba proteins 95-97%. Protein quality for maintenance was high and similar for all proteins. Acetylation affected neither N digestibility nor protein quality under maintenance conditions.
