Intestinal mucosa develops in a sex-dependent manner in Japanese quail (Coturnix japonica) fed Saccharomyces cerevisiae.

1. The aim of study was to investigate whether the impact of the yeast Saccharomyces cerevisiae on the histological structure of the intestine, innervation of the small intestine wall, and basal biochemical serum parameters in Japanese quail was sex dependent. 2. One-day-old healthy male and female Japanese quail were fed either a basal diet containing no yeast (control group) or the basal diet plus 1.5% (15 g/kg of diet) of yeast (S. cerevisiae inactivated by drying). Samples from the duodenum and jejunum were taken from each bird at the age of 42 days. Blood samples were collected at this age and the concentrations of glucose, total protein, creatinine, uric acid, lipid profile (total cholesterol, low density lipoproteins (LDL), high density lipoproteins (HDL) and triacylglycerols (TG)), alanine aminotransferase (ALAT), aspartate aminotransferase (AspAT), lactate dehydrogenase (LDH), amylase (AMY), calcium, phosphorus and iron were determined. 3. Female quail fed diets supplemented with yeast had significantly lower total cholesterol and amylase activity than the control females. The concentration of HDL was higher in the male quail than in the females, irrespective of the treatment. An opposite effect was observed in LDL. The diet treatments influenced the activity of AspAT, which was significantly less in the male quail fed diets with 1.5% yeast. 4. Supplementation with S. cerevisiae increased the myenteron, submucosa and mucosa thickness, villus length and thickness and size of absorptive surface, while the number of villi and enterocytes were decreased in the duodenum in males. Female quail showed an increased absorptive surface in the jejunum. The Meissner (submucosal) plexuses were influenced by the feeding and sex to a greater extent than the Auerbach plexus (in the muscularis propria). 5. The results demonstrated that S. cerevisiae (1.5%) in the diet caused significant positive effects in Japanese quail, exerting an effect on the morphology of the small intestine in a sex-dependent manner.

Selenium intake of infants and young children, healthy children and dietetically treated patients with phenylketonuria.

In 20 healthy infants and children, 5-20 months old, the Se intake was estimated by analysing food samples by instrumental neutron activation analysis. The intake was calculated by weighing the portions offered and actually consumed. The median Se content of the food amounted to 27 ng/g wet weight (gww) and median daily Se intake to 33.5 micrograms. The Se intake was not equally distributed over the day. About 50% of the daily Se intake was derived from the supper. The main Se sources (41%) for young children were cereal paps. Commercially available meals (30 ng/g) contained less Se than home-made ones (50 ng/g). In nine dietetically treated patients with phenylketonuria the median Se intake amounted only to 6.9 micrograms/day corresponding to a mean Se content of the diet of 7.9 ng/g. The main Se source in the diet was vegetables (36.3%) and 20% derived from their protein supplements. The Se intake of young children, healthy or dietetically treated, cannot be calculated accurately from tables but must be estimated by measuring the Se content of the local food because cereals and vegetables--the main Se sources--exhibit great regional variations.

The selenium content of infant food.

The selenium content of food exhibits great regional differences. Food samples of infants and young children from the North Rhine-Westphalia State in the Fed. Rep. of Germany were analysed by instrumental neutron activation analysis and showed that the average selenium content of local vegetable and fruit is below 5 ng/g wet weight. Only samples of potatoes and bananas exhibit higher selenium contents. The bananas, probably imported from different areas of the world, show an extremely high variance with values between 4 and 164 ng Se/g. Commercially available ready-for-use meals for infants or young children have a low Se content (median 24 ng/g) which is comparable to cow's milk. Besides eggs, cereals enriched with milk and some other cereal products contain more than 100 ng Se/g.

Zinc status of Libyan children -- a pilot study.

Hair zinc has been investigated in children of North and South Libya. The hair zinc content amounts to 213 +/- 36 micrograms/g in newborns. There is no difference between the values of newborns from North Libya and newborns from South Libya. The hair zinc values decrease during infancy. In toddlers and school-children the hair zinc content is 88 +/- 35 micrograms/g, 89 +/- 25 micrograms/g resp. These values are as low as those reported in American children with low height percentiles or nearly as low as those found in dwarfs with poor zinc status from Egypt and Iran.

Hair selenium content during infancy and childhood.

Hair selenium content was estimated by instrumental neutron activation analysis in Libyan infants and children. There was no significant difference between the values of young infants from North and South Libya. The hair selenium content rapidly decreased from 1071 +/- 75 ng/g in newborns to 301 +/- 99 ng/g in 7-10 months old infants in North Libya and to 557 +/- 204 ng/g in South Libya. In North Libya the values of preschool children were 409 +/- 117 ng/g and those of school children 464 +/- 124 ng/g.

Selenium supplementation: plasma glutathione peroxidase an indicator of selenium intake.

Plasma glutathione peroxidase activity is markedly reduced in dietetically treated patients with PKU or MSUD in comparison to health children of the same age. This is due to the low selenium content of their diet. During supplementation with yeast rich in selenium (200 micrograms selenium per day) for 3 months 2 healthy adults did not show any significant change of their plasma GSHPx activity. 5 dietetically treated patients with PKU or MSUD and a reduced selenium state showed a rapid increase of the plasma GSHPx activity after selenium supplementation were started with 120 micrograms Se/m2 x d. The values doubled within the first two days and reached a plateau after 1--3 weeks. The patients showed no clinical anomalities before or during the selenium supplementation besides the inherited defect of amino acid metabolism. Plasma GSHPx activity seems to be a good indicator of short-term changes of selenium intake in patients with reduced selenium state.

Determination of Co, Cu, Fe, Hg, Mn, Sb, Se and Zn in milk samples.

Concentrations of Co, Cu, Fe, Hg, Mn, Sb, Se and Zn in IAEA milk (dry) standard A-11 were re-evaluated with the help of instrumental and radiochemical neutron activation analysis (NAA). The results show reasonably good agreement for Co (5.1 +/- 0.55 ng/g) and Zn (34 +/- 2.5 micrograms/g), in relation to the recommended values. For Cu (374 +/- 15 ng/g), Fe (2.4 +/- 0.34 microgram/g) and Mn (250 +/- 20 ng/g); the results obtained are lower than the reported values. Cu, Mn, and Zn were cross-checked by atomic absorption spectrophotometry (AAS). The results, Cu = 331 +/- 27 ng/g, Mn = 302 +/- 62 ng/g, and Zn = 35 +/- 1 microgram/g, fall within the range of mean values obtained by NAA. for Hg and Se, using instrumental NAA, only upper limits could be indicated; because of the low levels of concentrations of Hg and Se on one hand, and high content of P (9100 micrograms/g) in A-11 milk standard on the other, NAA coupled with radiochemistry is to be preferred for these two elements. In pooled human milk, in addition to Cu and Mn (radiochemical) and Co, Fe, Sb and Zn (instrumental), Hg and Se could also be determined non-destructively because of the favorable Hg/P and Se/P ratios in this matrix.

Trace element concentration in the human pineal body. Activation analysis of cobalt, iron, rubidium, selenium, zinc, antimony and cesium.

100 human pineal bodies (56 male and 44 females) were analyzed by means of instrumental neutron activation analysis for trace concentrations of cobalt, iron, rubidium, selenium, zinc, antimony and cesium. The results indicated that the measured element concentrations are not related to body-surface, age and fresh weight. Moreover, the mean absolute cobalt value from 97 pineal bodies is increased by a factor of 1.43 over the mean absolute concentration value of 257 other areas of the brain. The mean zinc content is found to be 3.7 fold higher than the mean zinc value from 269 other samples of brain. The iron values from various brain areas do not differ from those of the pineal body. Compared to other brain regions pineal selenium is increased and rubidium is decreased. Correlating the different element concentrations to each other, a positive correlation is found for selenium and ribidium, a negative correlation for cobalt and zinc. The present data suggest that the measured trace elements are somehow related to specific roles in the physiology and biochemistry of the pineal body. This is supported by the constancy of element concentration over a wide range of increasing fresh weights of the organ. It is considered that zinc, cobalt and iron are involved as constituents of enzymes in the metabolism of amino acids, peptides and proteins of the pineal body. Moreover the conspicuous high zinc content of this organ may be related to a so far undetected neurotransmitter.

Selenium and myocardial infarction: glutathione peroxidase in platelets.

The activity of the selenoenzyme glutathione peroxidase (EC 1.11.1.9) was determined in platelets of 15 patients with acute myocardial infarction and 13 control subjects. The platelets of the patients had significantly lower activities of the enzyme (P(t) greater than 0.99). This may be related to the pathogenesis of the disease.

Concentration differences between serum and plasma of the elements cobalt, iron, mercury, rubidium, selenium and zinc determined by neutron activation analysis.

The differences in concentrations of cesium, cobalt, iron, mercury, rubidium, selenium and zinc between serum and plasma were examined with the aid of instrumental neutron activation analysis. Eighty serum and plasma samples obtained from 13 donors were compared. Serum was prepared in plastic tubes immediately after clotting, and plasma was separated with heparin as anticoagulant. No significant differences in the concentrations of cesium, cobalt, mercury and selenium were observed. However, the concentrations of iron, rubidium and zinc were significantly higher in serum than in plasma. The average differences were 322, 12 and 20 ng/ml for iron rubidium and zinc, respectively. The average differences found for cesium, rubidium and zinc were far below that which can be expected from a complete, or considerable release of these elements from platelets which aggregate or disintegrate during the clotting process in preparing serum.

Selenium requirements in patients with inborn errors of amino acid metabolism and selenium deficiency.

The diets of 5 patients with phenylketonuria of maple-syrup-urine disease were supplemented with yeast which was rich in selenium. For 120 days the patients received 45 micrograms Se/day to increase the Se content of their diets to 10--12 ng Se/Kjoule. Before supplementation the selenium content of serum (5--15 ng/ml) and whole blood (10--27 ng/ml), and the activity of the erythrocyte glutathione peroxidase (0.19--2.69 U37/g Hb), amounted to only 10--20% of normal. The serum selenium content reached normal values within 4 weeks of supplementation, followed by normalisation of the selenium content of whole blood within 4--8 weeks. Restoration of the activity of erythrocyte glutathione peroxidase took 9 to 15 weeks--the red cell life span. There was a significant positive correlation between the selenium content of the erythrocytes and the activity of erythrocyte glutathione peroxidase.

Elemental composition of platelets. Part III. Determination of Ag, Au, Cd, Co, Cr, Cs, Mo, Rb, Sb, and Se in normal human platelets by neutron activation analysis.

The elements Ag, Au, Cd, Co, Cr, Cs, Mo, Rb, Sb, and Se were determined in platelets from seven normal donors. The results, in ng/g wet weight, for plasma-free platelets follow: "Pure" platelets: Ag = 29 +/- (18), au = 0.22 +/- (0.22), Cd = 6.2 +/- 3.4, Cs = 54.8 +/- 19.2, Cr = 6.1 +/- 2.5, Co = 7.5 +/- (5.0), Mo = 3.4 +/- 1.3, Rb = 10400 +/- 3000, Sb = 18 +/- (26), and Se = 782 +/- 127. "Impure" platelets: Au = 0.23 +/- (0.28), Cd = 6.4 +/- 2.6, Cs = 35.2 +/- 13.8, Cr = 8.2 +/- 2.9, Co = 2.9 +/- (3.0), Mo = 3.2 +/- 0.8, Rb = 8700 +/- 1700, Sb = 13.2 +/- (8.7), and Se = 679 +/- 57. To our knowledge, none of these 10 trace elements has been determined in platelets before. The selenium concentration in platelets exceeds that in other tissues (e.g., liver). We suggest that glutathione peroxidase or other unknown selenoenzymes are particularly important in platelet metabolism. Platelets are crucial for triggering thrombosis, and so may be involved as links between selenium deficiency and the concomitant increased death rate from cardiovascular disease.

Selenium content of human milk, cow's mild and cow's milk infant formulas.

The selenium content of human milk, cow's milk and cow's milk infant formula were estimated by instrumental neutron activation analysis. The highest values were found in 3 samples of human colostrum (524--865 x 10(-9) g/g dry weight). There was a significant decrease with increasing time post partum. Mature human milk exhibited a selenium content of 230 +/- 79 x 10(-9) g/g dry weight. The selenium content of 45 samples of cow's milk from the north-western area of Germany was 200 +/- 39 x 10(-9) g/g dry weight. While there was no significant difference between the values of mature human milk and of cow's milk, cow's milk infant formula exhibited significantly (P less than 0.01) lower values than human milk. The average selenium content of 107 samples of 10 different commercially available fluid and powdered cow's milk infant formulas (range: 18--171 x 10(-9) g/g dry weight) amounted to about only one third of that in mature human milk.

Retention of the metabolized trace elements in biological tissues following different drying procedures. I. Antimony, cobalt, iodine, mercury, selenium and zinc in rat tissues.

Loss of Sb, Co, I, Hg, Se and Zn during freeze-drying and oven-drying at 80, 105 and 120 degrees C were studied in rat tissues that contained metabolized radioactive isotopes. No loss was observed for any of the 6 elements on freeze-drying. However, tissue-specific differences were observed in many cases for Hg, Se, I and Sb on oven-drying. A significant loss of Hg was observed in liver even at 80 degrees C, and for brain at 105 degrees C. Se was lost from whole blood, brain, lung, and muscle at 120 degrees C. Sb was lost from whole blood at 105 degrees C, but from brain, kidney, lung and spleen at 120 degrees C. Iodine was also lost from whole blood, kidney, blood serum, erythrocytes, brain, lung and muscle at 120 degrees C. Although the losses were statistically significant, they remained in most cases between 2 and 10%, with the exception of Hg at 120 degrees C, where the losses in some of the tissues were unpredictable. For urine, freeze-drying and oven-drying at 80 degrees C was found to be relatively safe for Hg and I. At 105 degrees C and above, serious loss of Hg was observed. In this experiment, the elements Zn, Co, Sb and Se were no studied for urine.

The selenium state of children. II. Selenium content of serum, whole blood, hair and the activity of erythrocyte glutathione peroxidase in dietetically treated patients with phenylketonuria and maple-syrup-urine disease.

The selenium content of serum, whole blood and hair was measured by neutron activation analysis in dietetically treated patients with phenylketonuria (PKU) and maple-syrup-urine disease (MSUD). Follow-up studies showed a decrease of the serum selenium content and the glutathione peroxidase activity of erythrocytes--a selenoenzyme--from normal values at the beginning of the diet to 20% (selenium) and 50% (gluthione peroxidase) of normal within 10--12 weeks of dietary treatment. In 36 patients the serum selenium content was lower at 6.7--28 X 10(-9) g/ml, independent of the age of the patients (0.5 to 10 years). The selenium content of whole blood was reduced: median = 98 X 10(-9) g/g dry weight; range 75 to 165 X 10(-9) g/g dry weitht (healthy children: median = 381 X 10(-9) g/g dry weight; range 245 to 588 X 10(-9) g/g dry weight). The selenium content of hair was markedly lower in the patients (median = 62 X 10(-9) g/g; range 13--140 X 10(-9) g/g) than in healthy children (median = 429; range 213 to 720 X 10(-9) g/g). The mean glutathione peroxidase activity of erythrocytes was reduced to 4.6 +/- 0.64 U37/g Hb, comparison to normal values (mean = 8.8 +/- 0.88 U37/g Hb).

The selenium state of healthy children. I. Serum selenium concentration at different ages; activity of glutathione peroxidase of erythrocytes at different ages; selenium content of food of infants.

The selenium concentration of serum is age-dependent. The median value at birth (chi=50 X 10(-9)g/ml) amounts to half of the median value of adults (chi=102 X 10(-9)g/ml). After a decrease in early infancy to chi=34 X 10(-9)g/ml it steadily increases to chi=58 X 10(-9)g/ml in the second half of the first year, to chi=82 X 10(-9)g/ml in 1--5 year old children, and to chi=92 X 10(-9)g/ml in school children. The activities of the selenium containing enzyme glutathione peroxidase of erythrocytes are also reduced in early infancy (chi=7.2 +/- 0.36 U37/g Hb), whereas the enzyme activities of cord blood erythrocytes (chi=8.72 +/- 0.76 U37/g Hb) are in the same range as those of older children or adults. The selenium content of some commercially available milk formulas for infants are lower than those of human and cow's milk.

Serum-selenium concentrations in patients with maple-syrup-urine disease and phenylketonuria under dieto-therapy.

Serum-selenium concentrations were measured in 2 dietetically treated patients with maple-syrup-urine disease, in 11 dietetically treated patients with phenylketonuria, in 37 healthy children of different ages and in 183 healthy adults. The estimations were performed by instrumental neutron activation analysis. The values of the dietetically treated patients were much lower than those of healthy children of the same age group. Within 8 to 12 weeks the serum-selenium concentrations decreased from normal values before therapy to very low values under dieto-therapy. During infancy the serum-selenium concentrations of healthy individuals show an increase to the adult range of values.

Trace element concentration in human brain. Activation analysis of cobalt, iron, rubidium, selenium, zinc, chromium, silver, cesium, antimony and scandium.

Up to 60 tissue samples were dissected from 13 human brains in defined regions and were analysed by means of neutron activation analysis for trace element concentration of cobalt, iron, rubidium, selesium, zinc, chromium, silver, cesium, antimony and scandium. It was shown that the variation in concentration of the non-essential elements in the different brain regions was greater than the corresponding variations in concentration of the essential elements. The mean values of Fe and Rb concentrations were higher in the basal ganglia than in the cortex areas. With increasing age the Fe concentration in the human brain was found to increase and that of Rb to decrease. Comparison of the trace element concentration in corresponding areas of the right and left hemispheres showed highly significant positive correlations for the essential elements. The concentration of each of the essential elements Fe, Rb and Zn was also found to differ significantly between defined functional regions. The characteristic distribution of essential trace elements in different areas is discussed in the light of known metabolic functions of these elements.