Akimasa Higashi

Mild to moderate zinc deficiency in short children: Effect of zinc supplementation on linear growth velocity

Twenty-one prepubertal, short Japanese children (11 boys) without endocrine abnormalities were identified as having mild-to-moderate zinc deficiency by zinc kinetics studies (zinc body clearance > or = 20 ml/kg per hour). Only one child had a serum zinc level < 65 micrograms/dl (cutoff level). A total of 10 children (5 boys) received 5 mg/kg per day of zinc sulfate for 6 months; 11 untreated children (6 boys) served as control subjects. During treatment, calorie intake (p < 0.01), growth velocity (p < 0.01), serum zinc, calcium, and phosphorus concentrations, alkaline phosphatase activity (p < 0.001), percentage of tubular reabsorption of phosphorus (p < 0.05), ratio of maximal tubular reabsorption rate for phosphorus to the glomerular filtration rate (p < 0.05), serum osteocalcin level (p < 0.01), and plasma insulin-like growth factor 1 (p < 0.05) were significantly increased, but urinary excretion of growth hormone was unchanged in the zinc-supplemented group. All these values were unchanged in the untreated children. We conclude that zinc supplementation is effective for inducing growth in short children with zinc deficiency, and that body zinc clearance tests facilitate detection of marginal zinc deficiency.

Longitudinal changes in selenium content of breast milk.

ABSTRACT. The selenium (Se) contents of human milk, serum and hair obtained from 22 lactating mothers were measured by fluorometric analysis. The Se contents in 41 milk samples from different stages of lactation were obtained longitudinally from 10 mothers. They showed a large variance of individual samples at any stage of studies. The highest Se level was found in colostrum (median 80 ng/ml); subsequently, Se content declined significantly during the first month of lactation and then came to a plateau level (median 17–18 ng/ml). No positive correlation of Se content was found between the serum and the milk samples at three months of lactation. No positive correlation of Se content was found between the hair and the milk samples obtained from lactating mothers.

Kinetics of Zinc Status in Children With IDDM

Objective To ascertain zinc deficiency in patients with insulin-dependent diabetes mellitus (IDDM) and evaluate the relationship between zinc clearance and body height velocity. Research Design and Methods Six boys and 11 girls with IDDM and zincuria and glycosuria were studied. Study quality and specific descriptive information concerning relationship and outcome measurement were assessed. Results The values of total-body zinc clearance in IDDM patients were higher than in the control subjects (24.6 ± 1.8 vs. 15.1 ± 0.6 ml · kg−1.h−1, P < 0.01). There was a negative correlation between body zinc clearance values and height velocity in IDDM patients. Conclusions Patients with IDDM have a secondary zinc deficiency, and normal growth may be stunted.

Effects of zinc and copper content of formulas on growth and on the concentration of zinc and copper in serum and hair.

We studied the effect of dietary zinc (Zn) and copper (Cu) on the levels of these elements in serum (at 1, 3, and 5 months of age) and in hair (at 5 months of age) of breast- and formula-fed infants. Three different formulas were used: (a) Commercially available standard infant formula containing 1.0 mg/L of Zn and 30 micrograms/L of Cu; (b) Zn supplemented formula, containing 3.2 mg/L of Zn and 30 micrograms/L of Cu; and (c) Zn- and Cu-supplemented formula, containing 3.2 mg/L of Zn and 400 micrograms/L of Cu. The median Zn content of breast milk was 4.8 mg/L at 1 week, 2.9 mg/L at 1 month, 1.1 mg/L at 3 months and 1.1 mg/L at 5 months. Breast milk Cu content was 510 micrograms/L at 1 week, 440 micrograms/L at 1 month, 270 micrograms/L at 3 months, and 200 micrograms/L at 5 months after delivery. All infants were healthy and full term, and weight and length velocities were similar in each of the four groups studied. Serum Zn levels were significantly higher both in the infants fed the Zn-supplemented formula and those fed the Zn-and-Cu-supplemented formula compared with the other two groups of infants at 3 and 5 months of age. Zn levels in hair were significantly elevated (invariably greater than 80 micrograms/g) only in infants fed Zn-supplemented formula.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of low-content zinc and copper formula on infant nutrition

The zinc (Zn) content of commercially available formula milks in Japan is less than that of breast milk obtained during the first three months of lactation, but is similar to that at five months of lactation. The copper (Cu) content of the formula milks is much lower than that of breast milk obtained during the five months. These two trace elements were measured in serum (at birth, one, three and five months of age), hair (at birth and at five months of age) and urine (at one, three and five months of age) of twenty-one breast fed and twenty formula fed full term infants. Despite the differences in Zn and Cu intakes, these parameters were similar in these two infant groups, except for urinary Zn at one and three months of age. These were significantly higher in breast fed infants (P<0.005 and P<0.05).Weight and length increments were not different in either infant group. It appeared that normal, full term infants tolerated low-content Zn and Cu formula milks well. This observation, however, is not at vaiance with the FAO/WHO recommendation for prevention of Zn and Cu deficiency.

Zinc Status Relates to Hematological Deficits in Middle-Aged Women

OBJECTIVE The objective of our study was to investigate zinc (Zn) status and the effects of Zn supplementation in relation to iron deficiency anemia in middle-aged women. It is important to define the role of Zn in hematologic abnormalities and to determine the frequency of Zn deficiency. METHODS Fifty-two Japanese women, selected from a health examination survey on 6200 women, had hemoglobin concentrations below 12.0 g/dl, total iron binding capacity (TIBC) below 390 micrograms/dl and fairly normocytemia. These 52 were divided into three groups and we then compared the hematological status before and after iron (group A) or Zn (group B) or iron plus Zn (group C) supplementation. RESULTS After treatment, concentrations of hemoglobin (Hb) increased slightly in groups A and B, but not statistically significant. In group C, Hb levels were significantly increased from 10.8 +/- 1.1 to 12.8 +/- 1.1 g/dl. Furthermore, numbers of RBC and reticulocytes, and concentrations of albumin were also increased significantly. Increased values over 1.0 g/dl of hemoglobin levels were noted in four women (26.6%) in group A, three women (14.2%) in group B and 13 women (81.2%) in group C. CONCLUSION Zn status to some extent can account for hematological abnormalities in middle-aged women. At least 5.0% of middle-aged Japanese women may have Zn deficiency. Normocytic anemia with low TIBC levels may serve as a good indicator of a marginal Zn deficiency.

Zinc kinetics in patients with bone demineralization due to physical immobilization.

To examine the relationship between zinc (Zn) status and bone demineralization, a body Zn kinetics study was performed with 74 (37 male, 37 female) disabled persons ranging in age from 16 to 45 years. Three groups were classified according to degree of limited mobility: group 1 (n = 23), capable of walking; group 2 (n = 20), capable of crawling; group 3 (n = 31), bed-ridden, Serum Zn levels were similar in the three groups, whereas body Zn clearance and the distribution of Zn showed a pattern [group 1 < group 2 < group 3 (p < 0.01, p < 0.05)], with the reverse in cases of bone mineral density (BMD) [group 1 > group 2 > group 3 (p < 0.01)]. Renal handling of Zn did not different among the three groups. There was a negative correlation between Zn distribution volume and values of BMD (p < 0.005, gamma = 0.387). Thus, various organs, as well as the skeleton, are Zn deficient in immobilized patients.

Zinc balance in premature infants given the minimal dietary zinc requirement

A zinc balance study was conducted on low birth weight infants (670 to 2420 g) fed unsupplemented human milk (the mothers or pooled) (group 1, n = 17) or human milk with zinc supplementation (group 2, n = 17). The mean zinc concentrations of the diets in groups 1 and 2 were 2.2 +/- 1.1 mg/L and 8.4 +/- 0.8 mg/L, respectively, and the mean copper concentration of the diets in both groups was 0.45 +/- 0.12 mg/L. The studies were performed 7 to 128 days after birth, which corresponded to 29 to 43 weeks postconceptional age. The turning point of zinc balance from negative to positive appeared to be greatly influenced by the postconceptional age, being approximately 36 weeks in both group 1 and group 2, rather than other factors such as the zinc intake and the postnatal age. The calculated minimal requirement of dietary zinc during the period from 36 to 40 weeks postconceptional age, for an adequate amount of zinc retention in infants (250 micrograms/kg/d), was 0.8 mg/kg/d. Zinc supplementation did not appear to interfere with copper retention.

Quantitative and Qualitative Changes of Apolipoprotein AI-Containing Lipoproteins in Patients on Continuous Ambulatory Peritoneal Dialysis

Using immunoaffinity chromatography, two species of apo-AI containing lipoproteins (AILp); lipoprotein containing apo-AI and apo-AII (Lp-AI/AII), and lipoprotein containing apo-AI, but no apo-AII (Lp-AI) were isolated from 13 female patients on continuous ambulatory peritoneal dialysis (CAPD), then characterized. The results were compared with findings obtained in agematched normolipidemic (control I) and mild hypertriglyceridemic (control II) female subjects. In comparison with control I: In AILp, the levels of total cholesterol (TC), cholesteryl ester (CE) and phospholipid (PL), and the levels of apoE were significantly lower in the CAPD patients while the levels of triglyceride (TG) and apo-CIII were significantly higher in these patients. The levels of apo-AI and apo-AII did not differ between the CAPD and control subjects. In Lp-AI/AII, changes of TC, CE, PL, TG, and apolipoproteins were similar to those of AILp, except for the ratio of apo-AI/apo-AII and the level of apo-CII, which was higher in the CAPD patients. In Lp-AI, changes of TC, CE, PL, and TG were also similar to those of AILp and Lp-AI/AII, but the apo-AI level was significantly lower in the CAPD patients. In comparison with control II: In AILp, the levels of PL, apo-AI, apo-AII, and apo-E were significantly lower in CAPD patients, but the apo-CIII levels were significantly higher. In Lp-AI/AII, the levels of PL and apo-E were significantly lower in CAPD patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Nutritional Copper Deficiency in Severely Handicapped Patients on a Low Copper Enteral Diet for a Prolonged Period: Estimation of the Required Dose of Dietary Copper

Six cases of nutritional copper deficiency were identified in a nursery institute for severely handicapped patients. All had been on prolonged enteral feeding of a copper-deficient diet and all had abnormalities related to the copper deficiency. Two of them had leukopenia, with or without macrocytic and normochromic anemia. After the oral administration of copper, the clinical and laboratory observations including neutrophil counts and serum copper and ceruloplasmin levels showed a complete recovery. The dietary copper requirement was estimated to be approximately 20 micrograms/kg/day for these patients, based on the correlation between the dietary copper intake and the levels of copper in the serum.