Fluctuations in human milk long-chain PUFA levels in relation to dietary fish intake

Within the Danish population, milk DHA (22∶6n−3) levels vary by more than a factor of 10. This paper deals with fluctuations in the milk content of 22∶6n−3 and other long-chain PUFA (LCPUFA) and the acute effects of fish meals and fish oil supplements on milk levels of LCPUFA. Twelve fish-eating mothers with 4-mon-old infants provided one blood and one adipose tissue sample, and seven consecutive morning hindmilk samples with dietary records from the previous days. Another 12 lactating women were given fish oil (2–8 g) for breakfast and delivered 6–12 milk samples during the following 24 h. The mean milk 22∶6n−3 content of the fish-eating mothers was 0.57±0.28 FA% (=percentage of total area of FAME peaks in GLC) and the day-to-day variation (SD/mean) within the individual was 35±17%. Mean milk 22∶6n−3 content on mornings with no fish the day before was 0.42±0.15 FA%; this was increased by 82±17% (n=9, P=0.05) if the mother had eaten fatty fish. Fish oil resulted in a twofold increase in milk 22∶6n−3 levels, which peaked after 10 h and lasted for 24 h. The EPA content of milk was also increased by fish meals and fish oil supplements, but these had no effect on the level of arachidonic acid. The study showed that diurnal and day-to-day fluctuations in levels of milk n−3 LCPUFA are large, which makes it difficult to assess the 22∶6n−3 intake of breast-fed infants from a single milk sample. In studies of the functional outcome of dietary 22∶6n−3 in breast-fed infants it is suggested also to use a measure of maternal 22∶6n−3 status.     

Calcium and magnesium concentrations in mature human milk: influence of calcium intake, age and socioeconomic level

Concentrations of calcium and magnesium were measured in mature milk, collected between 30 and 90 days after childbirth, from a group of 90 mothers between 14 and 39 years of age, exclusively breastfeeding. The group was divided into three sub-groups: low socioeconomic-level adolescents (LSAd), low socioeconomic-level adults (LSA), and high socioeconomic-level adults (HSA). Each mother's nutritional status was determined using the body-mass index (BMI) and her eating habits, obtained on the basis of a 24-h dietary recall. Adolescent and adult mothers in the low socioeconomic-level group had lower average calcium intake (LSAd = 618.4 +/- 555.2 mg and LSA = 679.4 +/- 411.4 mg) than adult mothers in the higher socioeconomic-level group (853.6 +/- 415.5 mg). The average concentration of calcium in the adolescent mothers' milk (LSAd) was significantly lower (5.30 +/- 1.42 mmol Ca/L, P = 0.01) than that of the two adult groups (LSA = 5.82 +/- 1.55 mmol Ca/L and HSA = 6.40 mmol Ca/L). The average magnesium concentrations for all groups did not show significant differences (LSAd = 1.06 +/- 0.18, LSA = 1.16 +/- 0.23 and HSA = 1.11 +/- 0.23 mmol Mg/L, for P= 0.16). These results indicate that magnesium concentrations in mature human milk do not seem to depend on maternal nutritional status. The condition of adolescence, however, associated with lower calcium intake by the mother, resulted in lower calcium concentrations in the milk secreted when compared to that of adult mothers.     

Prenatal diet, nutrient intake and pregnancy outcome in urban Ecuadorian primiparas.

A nutritional survey was conducted in an urban public maternity hospital, Hospital Gineco-Obstétrico Isidro Ayora (HGOIA), located in Quito, Ecuador. Seventy-four primiparas in the third trimester of pregnancy were recruited to assess the influence of sociedemographic factors on food patterns and nutrient intake, and the interrelationship between prenatal nutrient intake, maternal weight gain and pregnancy outcome. Results of the regression analysis indicated that maternal education was the factor most strongly associated with nutrient intake, followed by monthly per capita income. Maternal nutrient intake was next analyzed and compared with the WHO (1974, 1985) and NRC (1980) recommended daily allowances. Results also indicated the average daily intake of energy, protein, phosphorus, vitamins C and A, thiamine, riboflavin, and niacin met or exceeded the recommended daily allowances. Dietary calcium and iron intake, however, were below recommendations. Sodium and fat intake were both relatively high. Higher dietary fat intake was associated with increased birth weight, while lower protein intake was associated with increased risk of delivering a low-birth weight baby. Maternal weight gain during the third trimester predicted baby birth weight and height but not head circumference.     

Zinc levels in term and preterm milk

Zinc is an essential element, important for early growth and development, and immune competence, which deficiency might be especially critical in preterm infants. Since published data have shown that some preterm milks have abnormally low zinc values, we decided to measure zinc levels in term and preterm milk, in order to assess if they were within normal values and if there were differences between both groups. Samples from 24 preterm and 20 term mothers (mean gestational age, 30.9 + 0.5 and 39.5 + 0.2 weeks, respectively) were collected and kept at -20 degrees C until analyzed by atomic absorption spectrophotometry, prior wet ashing with nitric acid. Both term and preterm milk showed zinc values within normal levels. No significant differences were registered between them. A decreasing trend was observed along time, which was significant between colostrum and mature milk samples (ANOVA, p < 0.05). In the term group, zinc concentrations in colostrum and mature milk (microgram/mL) (mean +/- SEM) varied between 6.96 +/- 0.69 y 2.44 +/- 0.11, while in the preterm group the values were 6.20 +/- 0.89 y 2.28 +/- 0.54. According to our results, zinc values in human milk were comparable between preterm and term mothers.     

Diabetes increases excretion of urinary malonaldehyde conjugates in rats

The effect of streptozotocin-induced diabetes on the urinary excretion of thiobarbituric acid test-positive materials was examined. In diabetic rats, urinary excretion of thiobarbituric acid reactive substances was increased 5-fold over that in nondiabetic animals. High-performance liquid chromatography of urine samples revealed that five of the six fractions previously found to be increased in vitamin E deficiency [Lee, H.-S., Shoeman, D.W., and Csallany, A.S. (1992)Lipids 27, 124–128] were also significantly increased in streptozotocin-induced diabetes. The data suggest that a high level of oxidative stress is induced by uncontrolled diabetes in rats. Paper No. 20,002 of the scientific series of the Minnesota Agricultural Experiment Station on research conducted under the Minnesota Experiment Station projects Nos. 18-058 and 18-085.     

Dietary intake of essential and long-chain polyunsaturated fatty acids in pregnancy

The dietary intake of EFA and long-chain PUFA (LCPUFA) by women with (n=14) and without (n=31) gestational diabetes mellitus (GDM) was determined by repeated 24-h recalls. Women with GDM consumed significantly more energy as fat compared with women who had uncomplicated pregnancies; absolute dietary fat did not differ. Dietary n−3 LCPUFA was substantially lower than the current recommendation for pregnancy, whereas intake of saturated FA (SFA) exceeded it. We conclude that replacing dietary sources of SFA with those of EFA and LCPUFA, especially n−3 LCPUFA, would benefit the dietary fat profiles of all pregnant women.     

氯化镁-石灰乳法制高纯氧化镁中试工艺条件研究

高纯氧化镁是一种重要的化工原料,在建筑材料、环保领域、农业、化学催化等方面有着广泛的应用。笔者以盐湖氯化镁和生石灰为原料,结合中试试验,对氯化镁-石灰乳法制备高纯氧化镁的生产过程进行了研究,使工艺得到进一步优化。考察了常温下,pH、洗涤次数、陈化等因素对氢氧化镁合成过程的影响,并确定了最佳优化工艺参数：pH约为9.5,洗涤次数3次,料浆无需陈化。该研究对氯化镁-石灰乳法制备高纯氧化镁的工业化生产有一定的指导意义。     

Concentrations of calcium,magnesium, sodium and potassium in human milk and infant formulas

Concentrations of calcium, magnesium, sodium and potassium were determined in 55 samples of mature human milk from Canary women and 5 samples of powdered infant formula. According to the literature our data fell within the normal intervals described for each kind of milk. The mean concentration of Ca, Mg, Na y K of powdered infant formula was higher than those concentrations found in the human milks. Significant differences among the concentrations of Ca, Mg and Na for the milks of the considered mothers were observed. Only the Ca intakes for infants fed with human milk were lower than those requirements recommended by the Food and Nutrition Board (1989). However, the infants fed with powdered infant formula had an adequate intake of all the studied metals. A progressive decrease of the Na, K and Ca concentrations with the lactation stage was observed. Maternal age, parity and sex of the newborns did not affect the metal concentrations significantly.     

Effect of dietary calcium during pregnancy and lactation on zinc levels in blood and bone, in rats

The effect of dietary calcium (Ca) level on maternal zinc (Zn) nutritional status was studied. Female Wistar rats, weighing 250-350 g, were fed during pregnancy and lactation with an experimental diet containing/100 g different levels of calcium: 0.2 g (low calcium: LCa), 0.6 g (normal calcium: NCa) or 0.9 (high calcium: HCa). Maternal blood samples were drawn from the tail at delivery and at the end of lactation. Laboratory determinations were: Zn in whole blood (WB) at delivery and weaning; Zn (ZnF) and Ca (CaF) in the ashed femur at weaning. The results (mean +/- SEM) were: ZnWB (microgram/ml) at delivery and weaning: LCa: 8.73 +/- 1.05; 12.8 +/- 2.02; NCa: 3.49 +/- 0.19; 3.73 +/- 0.37; HCa: 3.21 +/- 0.19; 3.85 +/- 0.27. CaF (mg/100 mg): LCa: 19.2 +/- 0.8; NCa: 21.4 +/- 0.6; HCa: 20.4 +/- 1.1. ZnF (microgram/100 mg): LCa: 30.2 +/- 0.9; NCa: 24.1 +/- 0.3; HCa: 24.1 +/- 0.9. ZnWB was significantly higher in LCa (p < 0.0001) regarding NCa and Hca. ZnF showed an increase and CaF a decrease in LCa regarding NCa and HCa (p < 0.0001). There were no significant differences in ZnWB, ZnF and CaF between NCa and HCa These results show that: there was no detrimental effect when dietary Ca content was increased by 50% above the normal requirements of the rat.; low dietary Ca during pregnancy and lactation produced an increase of Zn utilization, reflected in maternal blood Zn and in ZnF content.     

Effect of a new fermented soy milk product on serum lipid levels in normocholesterolemic adult men

This study was undertaken to verify the effect of a daily intake of a new fermented soy milk produced with Enterococcus faecium and Lactobacillus jugurti on the serum lipid levels in normocholesterolemic middle-aged men. The study was randomized, double-blind and placebo-controlled and was performed for a period of 6 weeks. Forty-four normocholesterolemic healthy, male volunteers, aged 40-55 years old were randomly separated in two groups: The F-group received 200 ml of the fermented product daily and the P-group received 200 ml of placebo (chemically fermented). The blood samples were drawn initially and after 3 and 6 weeks and serum values for total cholesterol, HDL-cholesterol and triglyceride were determined. The LDL-cholesterol value was estimated. No significant changes in the fermented group (F) were observed for total cholesterol, LDL-cholesterol or triglyceride levels, while the HDL-cholesterol level was significantly higher (p < or = 0.05) after 6 weeks. The total cholesterol and LDL-cholesterol levels were significantly higher (p < or = 0.05) in the placebo group (P), but no changes were found for the HDL-cholesterol and triglyceride levels during the experimental period. In conclusion, the intake of 200 ml/day of the fermented soy milk, produced with E. faecium and L. jugurti, for 6 weeks, did not affect the serum total cholesterol and LDL-cholesterol, and led an increase of 10% in the HDL-cholesterol level.     

微波消解-原子发射光谱法测定奶粉中的钙、镁和钠

采用微波消解的方法处理奶粉样品,利用微波等离子体炬原子发射光谱法（MPT-AES）测定奶粉中的Ca、Mg、Na。考察了奶粉的最佳消解条件、溶液中盐酸浓度、硝酸浓度、共存离子浓度、微波前向功率、载气流量、工作气流量等实验参数对测定的影响。测定结果表明,Ca、Mg、Na质量浓度的检出限分别为0.92μg/L、0.36μg/L、0.75μg/L,线性范围分别为0.02～6 mg/L、0.02～9 mg/L、0.02～4 mg/L,RSD（n=6）≤0.41%。微波消解样品,缩短了制样时间,从而使工作效率明显提高。微波消解和微波等离子体炬原子发射光谱法相结合,是一种用于测定奶粉中微量元素含量的切实可行的方法。     

Seaweed intake and blood pressure levels in healthy pre-school Japanese children

Background

Low diet quality and depression symptoms are independently associated with poor glycemic control in subjects with type 2 diabetes (T2D); however, the relationship between them is unclear. The aim of this study was to determine the association between diet quality and symptoms of depression among Cuban-Americans with and without T2D living in South Florida.

Methods

Subjects (n = 356) were recruited from randomly selected mailing list. Diet quality was determined using the Healthy Eating Index-2005 (HEI-05) score. Symptoms of depression were assessed using the Beck Depression Inventory (BDI). Both linear and logistic regression analyses were run to determine whether or not these two variables were related. Symptoms of depression was the dependent variable and independent variables included HEI-05, gender, age, marital status, BMI, education level, A1C, employment status, depression medication, duration of diabetes, and diabetes status. Analysis of covariance was used to test for interactions among variables.

Results

An interaction between diabetes status, gender and HEI-05 was found (P = 0.011). Among males with a HEI-05 score ≤ 55.6, those with T2D had a higher mean BDI score than those without T2D (11.6 vs. 6.6 respectively, P = 0.028). Among males and females with a HEI-05 score ≤ 55.6, females without T2D had a higher mean BDI score compared to males without T2D (11.0 vs. 6.6 respectively, P = 0.012)

Conclusions

Differences in symptoms of depression according to diabetes status and gender are found in Cuban-Americans with low diet quality.     

Effect of solution concentrations and replacement levels of metakaolin on the resistance of mortars exposed to magnesium sulfate solutions

This paper reports an experimental study on the magnesium sulfate resistance of mortar and paste specimens incorporating 0%, 5%, 10% and 15% metakaolin (MK). The resistance of mortar specimens was evaluated using visual examination, reduction in compressive strength and expansion measurements.Results confirmed that mortar specimens with a high replacement level of metakaolin showed lower resistance to a higher sulfate concentration of magnesium solution. However, in a lower concentration, there were no visibly remarkable differences in the deterioration of mortar specimens, even up to 360 days of exposure, regardless of replacement levels of metakaolin.The negative effect of metakaolin on the magnesium sulfate resistance is partially attributed to the formation of gypsum but not ettringite and thaumasite. In addition, the reduction of calcium hydroxide and the increase of secondary C-S-H in the cement matrix due to pozzolanic reaction of metakaolin provided an opportunity to lead to the conversion of primary and secondary C-S-H gel into the M-S-H gel.It is concluded that it is necessary to pay special attention when using metakaolin in concrete exposed to highly concentrated magnesium sulfate solution.     

Effect of magnesium content on structure and dielectric properties of cubic bismuth magnesium niobate pyrochlores

Structure and dielectric properties of cubic pyrochlore Bi_1.5Mg_NNb_2.5−NO_8.5−1.5N (BMN) compositions with N=0.6–1.3 have been studied. X-ray diffraction (XRD), infrared reflectivity spectra and Raman spectra were employed to analyze the crystal structures and phonon vibration modes of BMN compositions. The vibration spectra were sensitive to the content of Mg²⁺ ions, which is caused by the randomness of Mg²⁺ ions partially filling both the cubic pyrochlore A and B sites. The intensity of A3O stretching vibrations became stronger with increasing Mg²⁺ content, but B3O stretching vibrations were quite opposite. With the increase of Mg²⁺ content, the dielectric constant and loss tangent both increased. Temperature dependent dielectric constant was observed in the samples with N>0.8. The tendency of the dielectric constant with the increasing temperature showed a quick drop in the samples with higher Mg²⁺ content, which seems to be associated with the disorder in the A₂O′ network.