Die DONALD Kohorte

The DONALD study has been conducted in Dortmund, Germany since 1985 to examine the complex relations between nutritional intake, metabolism and growth from infancy to adulthood. Every year, approximately 40 infants are newly recruited into the open cohort study. Examinations conducted at ages 3, 6, 9, 12, 18, 24 months and then annually until young adulthood, comprise anthropometry, a 3 day weighed dietary record, a 24?h urine sample (from age 3-4 years onwards), medical examinations and parental interviews. Since 2005, participants are invited for follow-up visits during adulthood (including fasting blood samples). Approximately 1,400 children have been recruited into the study up to 2010. Recent findings revealed e.g. (i) the relevance of early life factors for subsequent development of body composition and puberty timing, (ii) the relation between pubertal hormonal status and puberty onset, (iii) age and time trends in iodine status and modern dietary habits and (iv) potential furan and benzol exposition by commercial weaning foods. Future analyses will provide insight into the extent to which health in young adulthood is receptive to diet, anthropometric pattern and hormonal status in distinct potentially critical periods during childhood.     

Reviewing data reduction methods for ektacytometry

Ektacytometry quantifies erythrocyte deformability by measuring the elongation of suspended red blood cells subjected to a range of shear stresses. Raw shear stress-elongation index plots are difficult to interpret and thus data reduction methods characterizing the relationship using few parameters without loss of information and good reproducibility are essential, especially for the clinician. Two such curve fitting formulas, used widely in the literature for this purpose, are reviewed herein. The Lineweaver-Burke method overestimates maximal deformability if shear stresses below 1 Pa are applied. A modified version of the formula estimates maximal deformation more accurately but gives little weight to data at low shear stresses. Neither method is accurate if negative elongation indices are present (artifact phenomenon when measurement is performed from high to low shear stresses). The Streekstra-Bronkhorst method provides efficient data reduction though the theoretical background of the formula is incorrect. The parameters have expressive meaning; however, both maximal and minimal deformations are slightly underestimated. Moreover, parameters are biased according to the range of measured shear stresses.     

The toxicity of the quaternary ammonium compound benzalkonium chloride alone and in mixtures with other anionic compounds to bacteria in test systems with Vibrio fischeri and Pseudomonas putida

Mixtures of chemicals are present in the aquatic environment but standard testing methods assess only single compounds. One aspect of this question is the importance of the formation of ionic pairs, for example from quaternary ammonium compounds with organic anions, and the significance of the ionic pairs for bacterial toxicity in the aquatic environment. The aim of the present study was to investigate the toxicity of the cationic quaternary ammonium compound benzalkonium chloride (BAC) against aquatic bacteria in the presence of substances commonly found in wastewater, such as the anionic surfactant linear alkylbenzene sulfonate (LAS), naphthalene sulfonic acid (NSA), sodium dodecylsulfonate (SDS), and benzene sulfonic acid (BSA). The growth inhibition test with Pseudomonas putida and the Vibrio fischeri luminescent inhibition test were used to determine the toxicity of single compounds and compound mixtures. The results found in this study indicate that ion pair formation is of minor significance under the test conditions applied here.     

Using the concept of Food Based Dietary Guidelines to Develop an Optimized Mixed Diet (OMD) for German children and adolescents

OBJECTIVE: To apply for the first time FAO/WHO standards for Food Based Dietary Guidelines (FBDG) to develop a total diet concept named Optimized Mixed Diet (OMD) for children and adolescents in a European country. METHODS: Exact 7-day menus were composed for sample age groups of children (4-6 years) and adolescents (13-14 years), taking into account the German meal patterns, common non-fortified foods, and sensory preferences of children (practical criteria). Food amounts and food selection within the menus were optimized so far as to achieve a total of reference intakes for 22 nutrients (scientific criteria). Simple food based messages were deduced. RESULTS: Compared to the existing high-fat, low plant food diet reported from the DONALD Study (Dortmund Nutritional and Anthropometric Longitudinally Designed Study), the OMD is lower in fat and saturated fatty acids and contains ample amounts of plant foods. Reference nutrient densities for age groups between 1 and 18 years were achieved or exceeded, except folate. Foods from the optimized menus were summarized into 11 food groups based on nutritional and practical considerations. Proportions of food groups by weight are independent of age and can be used to recalculate food amounts for various age groups or energy requirements, respectively. For simplification, "recommended" foods were distinguished from "tolerated" foods by their nutrient densities; based on food amounts, 3 simple rules for food consumption were deduced, i.e. beverages and plant foods: ample; animal foods: moderate; high-fat, high-sugar foods: sparingly. CONCLUSIONS: Exact menus and food amounts are a prerequisite to ascertain nutrient adequacy of FBDG. The OMD demonstrates that a single diet concept with a core of quantified food groups can be adequate for age groups between 1 and 18 years within a country, such as Germany.     

Fifteen-year time trends in energy and macronutrient intake in German children and adolescents: results of the DONALD study

The DONALD study (Dortmund Nutritional and Anthropometric Longitudinally Designed study) gives the opportunity to evaluate long-term food and nutrient intake data on the basis of 3 d weighed dietary records of infants, children and adolescents since 1985. In this paper, we examine changes in energy and macronutrient intakes (protein, fat, saturated, mono- and polyunsaturated fatty acids, carbohydrates and added sugars) of 795 2-18-year-old subjects between 1985 and 2000 (4483 records). No significant changes in intakes of energy and of protein, polyunsaturated fatty acids and added sugars (as % energy intake, E %) were found. Fat intake decreased significantly in all age groups (between -0.20 and -0.26 E %/year), as well as intake of saturated fatty acids (between -0.11 and -0.14 E %/year) and monounsaturated fatty acids (between -0.07 and -0.014 E %/year). This decline was compensated for by a significant increase in carbohydrate intake (between +0.18 and +0.27 E %/year). The changes in macronutrient intake were mainly due to a decreased consumption of fats-oils (between -0.29 and -1.26 g/year) and meat-fish-eggs (between -0.21 and -2.92 g/year), whereas consumption of bread-cereals (between +0.12 and +2.42 g/year) and potatoes-pasta-rice (between +0.15 and +2.26 g/year) increased slightly. However, since recommended fat intake and fatty acid composition was not reached at the end of the study period by far, further efforts will be necessary to improve macronutrient composition and to stabilize favourable dietary habits.