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Young adult male and laying female quail, fed with a diet containing 2.64% Ca and 0.70% P, were used to study nutritive utilization, corporal calcium retention and endogenous excretion, calcemia, laying and properties of the egg (including the shell structure), mineralization of the femur bone, as well as the influence of diethylstilbestrol upon these parameters. The coefficient of nutritive utilization (C.N.U.) in the female was high and logically superior to that of the male, while the corporal retention was quite similar for both sexes. Most of the Ca absorbed (81.8%) and not excreted in urine, went to the egg and only 18.2% remained in the body. The diethylstilbestrol caused a big reduction of the C.N.U. in the female, but not in the male, parallel to an inhibition of laying, and an increase of corporal retention of used calcium. In both sexes the calcemia surprisingly increased, and the calcium level of the femur bone was higher, and even though the cortical osseous zone was slightly wider, the effect of treatment was noticeable, particularly in the medular tissue, which incremented in the female and appeared in the male. When quail were fed a calcium-restricted diet, the endogenous excretion of this mineral was small in the case of the female and significantly smaller in the male. This situation suppressed egg laying and resulted in a clearly decreased bone mineralization. The ingestion of diethylstilbestrol before feeding a diet poor in calcium provoked an increase of the endogenous excretion of calcium in both female and male quail.

The effect of oral vitamin D3 therapy on calcium balance was compared in 18 institutionalized subjects with drug-induced osteomalacia and in 18 similar subjects without osteomalacia. The subjects with osteomalacia were receiving standard doses of phenytoin and phenobarbital. Diagnosis of osteomalacia was based on low serum calcium and phosphorus, elevated alkaline phosphatase, and appropriate roentgenographic bone changes. The study group achieved positive calcium balance at approximately 975 IU of vitamin D3 per day, while the control group achieved positive calcium balance at approximately 380 IU of vitamin D3 per day. The difference is highly significant (p less than 0.001). These data support previous observations that the osteomalacia of patients receiving anticonvulsant drugs is related to the drugs and that these patients require supplemental doses of vitamin D.

Ten obese adolescents consumed the protein-sparing modified fast (PSMF), a high-protein, low-carbohydrate diet, for 92 +/- 19 d and lost 14.7 +/- 5.3 kg. The effect of weight loss using the PSMF on potassium, magnesium, and calcium was evaluated using balance method at days 2-4 and 12-20, RBC-Mg, RBC-K and total body K (TBK). The vitamin- and mineral-supplemented PSMF allowed positive Ca and K balance and improved Mg balance (p less than 0.005). TBK decreased significantly, 118.7 +/- 13.7 to 97.4 +/- 1.0 g (3.04 +/- 0.35 to 2.50 +/- 0.03 mol) from baseline to 90 d (p less than 0.001), with no change in the RBC-K concentration. An unexpected finding was a significant decrease in RBC-Mg, 3.2 +/- 1.1 to 1.8 +/- 0.3 mmol/L (p less than 0.001) after 60-90 d on the diet despite maintenance of normal serum Mg level.

Twelve male patients surviving uremia of 9-15 years duration were studied sequentially over a mean period of 9.2 years. Radiographs, bone biopsies, bone mineral mass (BMM) measured by photon absorptiometry, and total body calcium (TBC) determined by in vivo neutron activation analysis (NAA) were used. Pathologic fractures correlated with TBC corrected for height: 4 of 5 patients without fractures had TBC above 80% predicted, whereas 5 of 7 patients with fractures fell below this value. Unlike previous studies, negative calcium balance was seen in 3 patients with prolonged hyperparathyroidism. Though soft tissue calcification occurred in 6 patients, only 1 with massive shoulder calcification had an increase in TBC; this drawback of NAA has been previously overemphasized. Moreover, radial BMM also increased in 2 patients due to soft tissue calcification. When viewed at a single point in time, nearly all patients fell within the wide normal limits of BMM vs TBC. However, 6 patients with variable bone histology studied sequentially over a mean of 8.5 years showed significant preferential loss of radial bone mass compared to TBC. Aluminium retention did not influence calcium balance in these subjects.

Observations of many investigators point at a lower amount of calcium in body composition of Small-for-Date infants (S-f-D). So far, only few investigations indicated that the calcium metabolism is disturbed in the postnatal life of S-f-D infants as well. Taking into consideration these data, the authors attempt to define calcium-requirement in S-f-D infants. In this report the cross-sectional observations of 30 infants are described . They were born after 37 weeks of gestation. The mean body weight was 2318 and it ranged between 1200-2760 g. Their body weight at birth was below 10 percentile according to Brzozowska . In these infants 3-days balance studies were carried out once a month. The calcium balance indices were compared with the indices of the Full-Size infants (FS) who were observed during the former years. The S-f-D and FS infants were fed similar diets based on unmodified cow's milk formulas. It was noted that the percentage absorption index in S-f-D infants was significantly lower than in the control group in 1-st and 2-nd trimester of life (table III, fig. 2). The S-f-D infants had a good appetite in first semester of life and they ate a big volume of milk formula and calcium in it. It seems that this is the reason that calcium retention in S-f-D infants in spite of lower ability of calcium retention, did not differ statistically from calcium retention in FS infants. The mean values were a little lower however. In the 2-nd half year of life statistically significant difference between any of the balance indices in S-f-D and FS infants was not found.(ABSTRACT TRUNCATED AT 250 WORDS)

The high level of intratissue electric cooperation enables to detect tissue potentials with microelectrodes thick enough to destroy individual cells. Nevertheless, in ordinary perfused rat liver, these "cooperative potentials" (CP) coincide in the magnitude with usual cell membrane potential (MP). Intercellular dissociations, however, cause appreciable differences in CPs at different scales. The data obtained show possible role of cytoplasmic calcium in primary control of hierarhic tissue integrity.

In the former report on he calcium requirement in Small-for Date (S-f-D) infants it was observed that the ability of calcium absorption of S-f-D infants is lowered in 1-st semester of life. From this point of view it seemed purposeful to study the influence of 3 modified cow's milk formulas (see table) on the calcium absorption in S-f-D infants. Modification of these diets in regard to cow's milk depended on: 1) partial replacement of cow's milk fat with soya oil. 2) change of the proportion between fat and protein. 3) partial replacement of milk casein with lactoalbumin . The infants were divided into 3 groups G, H and C according to the kind of diet. Observation in the first 2 groups lasted for the whole first year of life, C group of infants was observed only in 1-st half year of life. In the first month of life G and H infants were fed the same unmodified cow's milk formulas (diet S) 3-day balance-studies. Were carried out once a month. The data of these 3 groups of infants were compared with each other and the data of S-f-D infants fed unmodified cow's milk formulas (group S) described in he former report. In group S, calcium intake was the highest in 1-st and in 2-nd semester of life among all compared infant groups, but the difference was not statistically significant. The lowest (%) absorption was noted in group G infants (fig. 2, table III and IV). The difference was statistically significant in 1-st semester of life between group G and S and in 2-nd semester between G and S as well as G and H groups. Calcium retention mg/kg was also the lowest in group G infants, and the difference was statistically significant in 1-st and in 2-nd semester between G and S groups. The infants fed H formula in spite of the lowest indices of calcium absorption % and retention mg/kg in the first (see table) and the second month of life and in spite of the lowest intake of calcium among all compared infants groups cough up absorption (%) and retention (mg/kg b.w.) with groups S in 2 semester of life.(ABSTRACT TRUNCATED AT 400 WORDS)

A 35-day experimental study consisting of 28-day growth and 7-day calcium (CA) balance periods was conducted to assess the effects of fibre and N ratios on growth and Ca balance of rats. Growth and Ca balance of rats (45 80 g) fed mixtures of cooked (CS) and uncooked (RS) sorghum and dehulled (DB) and undehulled (UB) bean were studied. The diets contained 10% protein. Casein served as the control protein. The control group ate more food except for the group fed the CS:DU (60:40) diets (P less than 0.05) had higher values for all parameters tested than the test groups. There were increases in food and Ca intakes, fecal Ca, weight gain, protein efficiency ration (PER), liver weight and composition except for the low moisture value for the CS:DS (60:40) group when N ratios were changed from 80:20 to 60:40. These results appear to indicate that fiber and N ratio had significant effects on growth liver composition and calcium balance of the rats.