Trace element status of PKU children ingesting an elemental diet

We assessed the trace metal status of 10 children (3.5 to 13.3 yr) with phenylketonuria (PKU) who were successively treated for at least 6 months with a semi-synthetic formula restricted in phenylalanine, then for 6 months with a reformulated formula. The reformulated product contained higher concentrations of magnesium (Mg), potassium (K), phosphorus (P), selenium (Se), and zinc (Zn) and lower concentrations of calcium (Ca), sodium (Na), and unsaturated fats. Diet records, blood samples, and urine specimens were collected from each subject. Mean intakes of Mg, K, and Zn increased significantly when subjects were switched to the reformulated product. The subject's mean intakes of Se (for all age groups) and Zn (children 11 to 14 yr old) were below 67% of recommended intakes while they were ingesting the original formula. The mean trace metal concentrations of urine, blood, and serum did not differ significantly during the two periods. Mean serum Zn, Se, and Cu concentrations of the subjects were less than those reported for normal children. Significant negative correlations were obtained between serum Zn concentrations and the molar ratio of dietary (Ca + P):Zn, and the molar ratio of dietary Fe:Zn. No significant differences in mean urinary Cu and Zn excretion (mg/g creatinine) were observed in subjects after they were changed to the reformulated product. Individuals whose primary source of energy and protein is derived from semi-synthetic elemental diets are especially at risk for multiple trace element deficiencies.     

Trace element nutrition status and dietary intake of children with phenylketonuria

The trace element status (copper, iron, zinc, manganese, chromium, and selenium) of 20 dietetically treated phenylketonuric (PKU) children was assessed. Significantly higher intakes of copper (p = 0.002) and iron (p = 0.005) were noted in PKU children compared with their siblings. No significant differences were found for zinc, manganese, or chromium. Intake of selenium was significantly lower (p = 0.0001) in PKU children (8.4 +/- 3.9 micrograms/d) than in siblings (41.6 +/- 9.4 micrograms/d). Plasma and urine selenium and erythrocyte glutathione peroxidase activity (GSHpx) were significantly lower (p = 0.001) in PKU children (0.38 +/- 0.11 mumol/L, 58.0 +/- 34.5 nmol/d, and 14.2 +/- 5.5 U/g Hb, respectively) than in siblings (0.82 +/- 0.15 mumol/L, 165.2 +/- 49.4 nmol/d, and 22.7 +/- 5.2 U/g Hb, respectively). No differences were found in plasma and urine concentrations of other elements. Intake of selenium was significantly correlated with erythrocyte GSHpx (r = 0.87, p = 0.0001) and plasma selenium (r = 0.71, p = 0.0001) for the combined groups. The need and possible procedures, including dietary manipulation, for increasing selenium intake in PKU subjects are discussed.     

Trace element intakes of women

1. Energy, protein, zinc, copper, manganese, selenium and dietary fibre intakes of 100 pre-menopausal women (mean age 30.0 +/- 6.1 years) from a university community, and consuming self-selected diets, were calculated using 3 d dietary records and food composition values. Subjects also collected a 24 h food composite during the 3 d record period for analysis of Zn, Cu and Mn by atomic absorption spectrophotometry. Daily analysed intakes were compared with those calculated from the corresponding record day. 2. Mean daily calculated intakes of energy, protein, Zn, Cu, Mn, Se and dietary fibre were 7.54 +/- 1.61 MJ, 74 +/- 18 g protein, 10.1 +/- 3.3 mg Zn, 1.9 +/- 0.6 mg Cu, 3.1 +/- 1.5 mg Mn, 131 +/- 53 micrograms Se, 19.4 +/- 6.6 g dietary fibre. 3. Major food sources for each of the trace elements were (%): Zn meat + substitutes 43, dairy products 23.7; Cu breads and cereals 22, vegetables 21; Mn breads and cereals 47, fruits 12, Se meat + substitutes 38, breads and cereals 30. 4. Highly significant correlations (P = 0.001) were noted for analysed intakes of Zn, Cu and Mn and those calculated from the corresponding record day. Mean calculated intakes were higher (%): Zn 138, Cu 142, Mn 121, than corresponding mean analysed intakes (P = 0.01). However, the mean nutrient densities (mg/MJ) were comparable: Zn analysed 1.2, calculated 1.4; Cu analysed 0.2, calculated 0.2; Mn analysed 0.4, calculated 0.4. 5. All subjects met the Canadian Dietary Standard (CDS) recommended level for Cu but 48% received less than the CDS for Zn, 6% obtaining less than two-thirds of this recommended level. Daily Mn and Se intakes were similar to recent values for North American diets.     

李沧区健康成人血中7种金属元素参考值调查

目的:描述青岛市李沧区健康成人全血中Zn、Fe、Cu、Mn、Mo、Se、Ca的含量及其分布特点,确定其在全血中的正常参考值范围。方法:采用微波消解—电感耦合等离子体质谱仪进行测定,数据使用SPSS11.5统计处理。结论:李沧区健康成人全血中金属元素的总体范围:Ca为41.4~64.7 mg/L、Fe为369.1~567.4mg/L、Zn为3.23~6.62 mg/L、Cu为0.602~1.068 mg/L、Mn为5.5~46.3μg/L、Mo为0.22~3.54μg/L、Se为62.2~143.1μg/L;其中,Fe、Zn、Cu呈正态分布,而Ca、Se、Mn、Mo呈偏态分布;正常参考值范围:男性Ca(mg/L):46.9~61.1,女性Ca(mg/L):43.1~64.5;男性Se(μg/L):63.3~134.5,女性Se(μg/L):65.6~135.8;男性Zn(mg/L):4.33~6.41,女性Zn(mg/L):3.52~5.52;男性Fe(mg/L):386.1~546.5,女性Fe(mg/L):386.6~492.5;男性Cu(mg/L):0.614~0.970,女性Cu(mg/L):0.694~1.030;Mn(μg/L):6.08~28.34;Mo(μg/L):0.22~1.54。     

Analyzed dietary intakes,plasma concentrations of zinc,copper, and selenium,and related antioxidant enzyme activities in hospitalized elderly women.

The purpose of the study was to assess the actual dietary intakes of zinc (Zn), copper (Cu) and selenium (Se) intakes in relation with some indicators of trace element status in a selected group of hospitalized elderly patients.

24 elderly women aged 76-99 years were recruited in the Geriatric Department of the Grenoble University Hospital.

Zn, Cu, and Se dietary intakes were estimated by duplicate portion analysis. Plasma trace element concentrations, Cu-Zn superoxide dismutase (Cu-Zn SOD) and Se glutathione peroxidase (Se GSH-Px) activities were determined in parallel.

Mean daily intakes of Zn (5.6 mg), Cu (0.67 mg), and Se (23 micrograms) were low, in relation with poor energy intake and nutrient densities. Zn and Se levels in plasma were lower and plasma Cu increased compared to reference values obtained from healthy younger subjects. Thirty-eight percent of the elderly patients had plasma Zn concentrations < 10.7 mumol/l, but Cu status appeared adequate as suggested by the lack of decline in Cu-Zn SOD activity. A high proportion of plasma Se concentrations < 0.76 mumol/l and the parallel decrease in erythrocyte and plasma GSH-Px activities suggest a Se deficiency in this population.

Our findings indicate that French hospitalized elderly patients may be at risk of Zn and Se marginal status and present altered antioxidant defenses in relation with low dietary intakes. It underlines the interest of supplementation studies in this population.     

饮水型地方性氟中毒病区儿童氟斑牙患病情况与血清化学元素的关系

目的探讨改水后儿童氟斑牙患病情况和儿童体内化学元素的关系。方法采用分层抽样调查方法,根据西安市疾病预防控制中心近20年的监测资料,将西安市饮水型地方性氟中毒病区按照改水年限1~、5~、10~及≥15年进行分层,每层抽取2个病区自然村为调查点。每个调查点选择7~13岁学龄期儿童为调查对象,检查氟斑牙患病情况;并采集血样,检测血清中14种化学元素(钙、铁、镁、铜、锌、碘、硒、铅、砷、镉、铬、氟、汞、镍)含量。分析不同改水年限以及不同氟斑牙患病情况儿童体内化学元素含量的差异。结果不同改水年限的病区村(1~、5~、10~及≥15年)儿童氟斑牙检出率分别为51.40%(55/107)、16.92%(11/65)、16.67%(17/102)和5.08%(6/118),差异有统计学意义(χ²=74.444,P<0.05)。不同改水年限儿童体内血清钙、铜、铁、镁、锌、碘、硒、铅、砷、铬、氟、镍含量比较,差异均有统计学意义(P均<0.05)。氟斑牙儿童体内铁、锌、镍含量均低于正常儿童(P均<0.05),氟斑牙儿童体内氟含量高于正常儿童(P<0.05)。氟斑牙儿童与正常儿童体内的其余化学元素含量比较,差异均无统计学意义(P均>0.05)。结论改水年限≥15年的病区村儿童氟斑牙检出率最低,改水降氟可减少儿童氟斑牙检出率。病区儿童存在部分化学元素缺乏的问题。     

Nutrient intakes of adolescents with phenylketonuria and infants and children with maple syrup urine disease on semisynthetic diets.

Adequacy of nutrient intakes of adolescents with and without phenylketonuria (PKU) and infants and children with and without maple syrup urine disease (MSUD) were assessed using 3-day diet records sorted by disease and by age of the subject. Mean intakes of all nutrients were greater than two-thirds of the Recommended Dietary Allowances (RDA) or Estimated Safe and Adequate Daily Dietary Intakes (ESADDI) for all adolescents studied, with the exception of selenium (Se) in PKU adolescents, which averaged 27.8 micrograms. For adolescents with PKU, > 50% of the RDA or ESADDI for all nutrients was provided by elemental or modified protein hydrolysate medical foods, except for vitamin A in children aged 11-15 years and Se in children 11-18 years. Mean nutrient intakes of all infants and children were greater than two-thirds of the RDA or ESADDI for all nutrients except Se in MSUD children aged 1-11 years, where intakes ranged from 6.4 to 13.2 micrograms (21-66% of the RDA). The medical foods provided for most of the RDA and ESADDI recommendations, with the exception of Se in MSUD children.     

Evaluation of the microelement profile of Turkish hazelnut (Corylus avellana L.) varieties for human nutrition and health

In this study, the levels of boron (B), cobalt (Co), copper (Cu), chromium (Cr), iron (Fe), lithium (Li), nickel (Ni), selenium (Se) and zinc (Zn) microelements in 16 hazelnut samples were determined by inductively coupled plasma mass spectrometry and atomic absorption spectroscopy after microwave digestion, and are discussed for human nutrition and health. Significant differences were observed between the microelement contents of the 16 varieties (P < 0.01). The average microelements concentrations in the varieties varied in the following ranges: B, 13.63-23.87; Co, 0.47-0.82; Cr, 0.22-0.52; Cu, 16.23-32.23; Fe, 31.60-51.60; Li, 0.035-0.042; Ni, 0.58-2.58; Se, 0.96-1.39; and Zn, 22.03-44.03 mg/kg. These results showed that hazelnuts can be an important microelement source for human nutrition and health. According to our trace element data, a daily consumption of 50 g hazelnut can supply easily about 6% for B, 9% for Co, 19% for Fe, 9% for Ni and 16% for Zn of the recommended daily allowance. On the other hand, Se, Cu and Cr levels of 50 g hazelnuts are higher than the respective daily requirements, but slight overdoses of these elements are non-toxic for human health.     

锌、铜、铁、钙营养状况与高血压病的相关研究

对５２例高血压患者进行头发中锌、铜、铁、钙等１０种元素的含量测定，并同时测算相应膳食中锌、铜、铁、钙及蛋白质和热能的摄入量。结果表明：①高血压组发锌、铜、钙、硒、铬、锰、锶含量均低于健康组，发铁、铅含量则高于健康组。②高血压组膳食中锌、铜、钙、蛋白质的摄入量均明显低于健康组及ＲＤＡ标准，而铁及热能的摄入量则高于健康组及ＲＤＡ标准。③高血压组膳食中锌、铜、铁、钙的摄入量分别与相应发含量及蛋白和热能的摄入量呈显著性正相关。结果提示，高血压患者头发中锌、铜、铁、钙等元素含量可用来评价其营养状况。微量元素含量变化与高血压病的发生发展有密切关系。     

Potential Toxic Metal Accumulation in Soil,Forage and Blood Plasma of Buffaloes Sampled from Jhang,Pakistan

This study was conducted to determine the concentration of toxic metals in soil, forage and blood plasma of lactating and non-lactating buffaloes in the district Jhang, Punjab, Pakistan. Soil samples were collected from varying distances from the road side. Plasma separation was achieved by centrifugation. The concentration of arsenic (As), selenium (Se), cadmium (Cd), chromium (Cr), iron (Fe), zinc (Zn), copper (Cu) and cobalt (Co) were determined by using Atomic Absorption Spectrophotometer. The results of the study showed that the mean As, Se and Cd concentrations in soil samples were lower while Cr, Fe, Zn, Cu and Co were higher than the official guidelines. In plasma samples, mean concentration values of Co, Zn, Fe, Cd, Se and As were lower while Cu and Cr were higher than the recommended concentrations. According to the results of the study there was no potential exposure of toxicity in buffaloes of the study area.     

Trace element status in multiple sclerosis

We compared trace element status in multiple sclerosis (MS) patients (n = 27) with and without treatment with corticosteroids and groups of healthy subjects. Concentrations of plasma ceruloplasmin, selenium, and zinc and erythrocyte (RBC) glutathione peroxidase, Se, and Zn were similar in all groups. RBC copper concentrations were significantly lower in MS patients than in control subjects (mean +/- SEM: 0.048 +/- 0.005 vs 0.060 +/- 0.002 mumol/g Hb) because of decreased RBC Cu with steroid therapy. RBC Zn-Cu ratios were significantly higher (14.9 +/- 1.0 vs 10.1 +/- 0.3) in MS patients than in control subjects, differing in both groups of MS patients. In MS and control subjects, RBC Cu correlated significantly with RBC Zn (r = 0.56, 0.49). Disease acuity and disability had no effect on trace-mineral status. These data suggest that in MS there is altered Cu and Zn homeostasis that may cause or result from the disease and is influenced by corticosteroid therapy. Systemic trace element alterations might provide clinically useful markers of MS.     

空港地区535例儿童全血微量元素水平分析

目的:了解北京市顺义空港地区儿童体内微量元素含量。方法:对535例6岁以下儿童采用原子吸收分光光度法检测全血中锌、铁、铜、钙、镁5种微量元素含量。结果:受检儿童锌、铁缺乏率较高,钙、铜含量偏高。结论:合理补充微量元素对儿童健康至关重要。     

Poor zinc and selenium status in phenylketonuric children and adolescents in Brazil

Because of the restricted intake of high-biologic-value protein, children with phenylketonuria (PKU) may have lower than normal plasma concentrations of copper, zinc, and selenium. The purpose of the present study was to investigate erythrocyte zinc levels and serum copper and selenium levels in children and adolescents with PKU by analyzing the relation between their diet and the laboratory profiles of these elements. The study was conducted in 32 children and adolescents with PKU, who were on a special diet. Dietary records and blood samples were collected from each subject. Erythrocyte zinc and serum selenium levels were below normal in 37.5% and 90.6% of the subjects, respectively. Plasma copper levels were normal. Metabolic formulas were the only source of 86.9% of the zinc, 65.6% of the copper, and 32.4% of the selenium. Despite this, there was no significant correlation between the zinc formula supply and erythrocyte zinc levels (ρ = −0.143, P = .435) or the supply and serum levels for copper (ρ = −0.117, P = .523) and selenium (ρ = 0.113, P = .538). These results suggest that Brazilian patients with PKU present with low ingestion levels, low serum selenium levels, and low erythrocyte zinc levels.     

Evaluation of the microelement profile of Turkish hazelnut (Corylus avellana L.) varieties for human nutrition and health

In this study, the levels of boron (B), cobalt (Co), copper (Cu), chromium (Cr), iron (Fe), lithium (Li), nickel (Ni), selenium (Se) and zinc (Zn) microelements in 16 hazelnut samples were determined by inductively coupled plasma mass spectrometry and atomic absorption spectroscopy after microwave digestion, and are discussed for human nutrition and health. Significant differences were observed between the microelement contents of the 16 varieties (P < 0.01). The average microelements concentrations in the varieties varied in the following ranges: B, 13.63–23.87; Co, 0.47–0.82; Cr, 0.22–0.52; Cu, 16.23–32.23; Fe, 31.60–51.60; Li, 0.035–0.042; Ni, 0.58–2.58; Se, 0.96–1.39; and Zn, 22.03–44.03 mg/kg. These results showed that hazelnuts can be an important microelement source for human nutrition and health. According to our trace element data, a daily consumption of 50 g hazelnut can supply easily about 6% for B, 9% for Co, 19% for Fe, 9% for Ni and 16% for Zn of the recommended daily allowance. On the other hand, Se, Cu and Cr levels of 50 g hazelnuts are higher than the respective daily requirements, but slight overdoses of these elements are non-toxic for human health.     

Balance study of twenty trace elements during total parenteral nutrition in man.

1. Balances of twenty trace elements (silver, arsenic, gold, bromine, cadmium, cobalt, chromium, caesium, copper, iron, mercury, lanthanum, molybdenum, rubidium, antimony, scandium, selenium, samarium, tungsten and zinc) have been determined in four male patients during total parenteral nutrition incliding fat emulsion and a special solution for addition of Fe, Zn, manganese, Cu, fluorine and iodine, besides calcium and magnesium, to the infusion solutions. 2. The analyses for trace elements were made with the aid of an ion-exchange technique based on neutron activation, and combined with subsequent gamma spectrometry. 3. The intended intravenous supply of trace elements correspond approximately to the analysed supply. However, all the other trace elements determined were found to be unintentionally administered in small amounts. 4.There was a substantial retention of Fe. Other elements retained were Ag, Co, Cr, Cu, Sb, Sc, and W. 5. Particularly Br and Rb were lost by the patients, but negative balances were also found for As, Au, Cd, Cs, Mo, Se and Zn. However, Zn was retained by one patient with short bowel syndrome. 6. The serum concentrations of thirteen (Ag, Br, Co, Cs, Cu, Fe, Hg, Mo, Rb, Sc, Se, W and Zn) of the trace elements were found to have some decrease during the period of total parenteral nutrition, mostly in accordance with the corresponding balance values, Fe, in particular, was found to have the derectional change in concentration. 7. The administration of trace elements is recommended in long-term total parenteral nutrition.     

Plasma zinc, copper, and erythrocyte superoxide dismutase in children with phenylketonuria.

Children with phenylketonuria (PKU) are treated with semisynthetic diets restricted in phenylalanine (PHE). The formulae must supply those trace elements and vitamins that are usually supplied by whole protein foods. We studied the effects of phenylalaline restricted diets in 42 children with PKU (P) and 31 normal (N) children, aged 1-12 y, divided into two groups (below and above 7 y). Plasma zinc and copper were analyzed by means of atomic spectrophotometry, and superoxide dismutase (CuZnSOD) activity was measured in erythrocytes, through NBT inhibition and its profile, as determined by isoelectric focalization. Plasma zinc of PKU children > or = 7 years old was significantly lower than that in the control group (17 mumol/L versus 20 mumol/L) but still within the normal range; in children < 7 years no substantial differences were found between the two groups. Plasma copper was not statistically different between PKU and normal children. Qualitative activity of CuZnSOD presented the same electrophoretic profile in both normal and PKU. Quantitative activity was not different in both P (1210 U/g Hb < 7 versus 1328 U/g hemoglobin (Hb) > or = 7) and N (1675 U/g Hb < 7 versus 1367 U/g Hb > or = 7). We concluded that children with PKU presented normal mean levels of zinc and copper, with preserved function, measured by enzyme activity.     

肺炎患儿全血微量元素测定及临床意义

目的:探讨肺炎患儿全血锌、铜、铁、钙、镁含量的变化。方法:采用火焰原子吸收法检测32例肺炎患儿和30例健康小儿的全血微量元素含量。结果:肺炎患儿全血锌、铁含量明显低于健康儿童(t分别=5.538和3.282,P=0.000和0.002),而血铜、钙、镁含量无明显差别(P均>0.05)。结论:肺炎患儿体内存在不同程度的锌、铁缺乏,对肺炎患儿应常规检查微量元素,适当补充锌、铁等金属元素以辅助治疗。     

Zinc and iron nutrition in Chilean children fed fortified milk provided by the Complementary National Food Program

OBJECTIVE: Chilean infants are at risk for isolated zinc and iron deficiencies because of a low consumption of animal products in low socioeconomic sectors. In 1999, the National Complementary Food Program of Chile manufactured a new milk (2 kg of powdered milk/mo) fortified with iron (Fe; 10 mg/L), zinc (Zn; 5 mg/L), and copper (0.5 mg/L) to be provided to infants until age 18 mo and to pregnant women. We analyzed the nutrition status of zinc and iron at age 18 mo in infants who consumed the fortified cow's milk. METHODS: Forty-two healthy male children with normal growth and from lower socioeconomic groups were studied. A nutrition survey was conducted; blood and hair samples for Zn in plasma and hair, hemoglobin, hematocrit, and serum ferritin were obtained. RESULTS: Mean intakes were: energy, 106 +/- 27 kcal. kg(-1). d(-1); protein, 3.8 +/- 1.1 g. kg(-1). d(-1); Zn, 5.2 +/- 1.9 g/d (0.98 mg Zn/MJ; 68% of World Health Organization recommendations); Fe, 11.2 +/- 5.5 mg/d; and dietary fiber, 9.8 +/- 3.9 g/d. Plasma Zn in 54.8% of children was no greater than 12.3 microM/L; 36% had hair Zn level no greater than 1.23 microM/g and 39% had serum ferritin levels no greater than 10 microg/dL (12% were anemic). Hair Zn was correlated to socioeconomic level (Spearman's rank correlation, r = -0.53; P < 0.001) and plasma Zn was correlated to the z weight/length (r = 0.47; P < 0.05), subscapular skinfold (r = 0.46; P < 0.05), and Zn intake (r = 0.46; P < 0.05). CONCLUSIONS: The fortified powdered cow's milk provided to infants until age 18 mo by the Complementary Food Program in Chile favorably affects the Fe status of these children, but possibly not the Zn nutrition; we suggest re-evaluation of the levels of Zn fortification.     

Mineral Concentrations in Cow's Milk from the Canary Island

Concentrations of selenium (Se), iron (Fe), copper (Cu), zinc (Zn), sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) were determined in samples of raw and sterilized cow's milk. The following mean concentrations (and ranges) were recorded in raw cow's milk: Se (μg/L), 16.44 (6.8–28.6); Fe (mg/L), 0.515 (0.19–1.00); Cu (mg/L), 0.076 (0.03–0.16); Zn (mg/L), 4.41 (2.3–6.6); Na (mg/L), 534.1 (278–870); K (mg/L), 1424 (1035–1874); Ca (mg/L), 1653 (1196–2236); Mg (mg/L), 113.9 (71.5–159.4). The sterilized cow's milk showed mean concentrations of Fe (0.170 mg/L) and Zn (3.06 mg/L) significantly lower than the concentrations observed in raw cow's milk; however, the mean concentrations of Se (14.90 μg/L) and Cu (0.110 mg/L) were similar and significantly higher than in raw cow's milk, respectively. No significant differences for Na, K and Mg were observed between the mean concentrations in raw and sterilized cow's milk. An important contribution to the daily intake of Ca and K for Canarian people due to the consumption of cow's milk was observed. Moderate amounts of Mg and Na, and smaller amounts of Zn and Se are also supplied. Our data for the mineral concentrations in cow's milk were within normal intervals of concentration described in the literature. The concentrations of Fe, Cu, Na, K and Ca in raw cow's milk remained approximately constant during the 12 months sampled. In contrast, the Se, Mg and Zn concentrations varied significantly with the climatic season, presenting the lowest mean concentrations during autumn.