ISSN:0731-5724    

DOI:10.1080/07315724.1983.10738050

出版商:Routledge    

年代:1983

数据来源: Taylor

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719929

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

Red blood cell and serum selenium concentrations were investigated to determine normal concentrations for our geographic area and if potential differences existed in patients with selected diagnoses (hepatic, renal, malignant, and chronic diseases). Selenium was quantified in samples of red blood cells, serum and urine by neutron activation analysis. The results were analyzed by comparing 1) pooled data from all ages for each disease with normal values, and 2) normal values with age-matched patients in each disease category. Decreases in red blood cell selenium concentrations (P less than 0.05) occurred in normal subjects over 60 years of age without concurrent significant decreases in serum selenium. Although differential results were noted in age-matched groups, overall results showed that decreased concentrations of selenium in both red cells and in serum occurred with alcoholic cirrhosis, malignancies, and chronic renal failure (P less than 0.025). Red blood cell selenium concentrations also were decreased in patients with stable chronic disease. Decreased serum selenium concentrations were positively correlated with albumin concentrations in patients with cirrhosis. There was no correlation between serum selenium and bilirubin concentrations in patients with liver disease or between serum selenium and creatinine concentrations in patients with chronic renal failure whose urinary excretion of selenium was far below control levels.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719930

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

The effect of varying the amount of dietary magnesium on the development of hypertension in spontaneously hypertensive (SH) rats was investigated with three diets containing 1.05% (H1Mg diet), 0.52% (H2Mg diet), and 0.008% (LMg diet). The control group was given a diet containing a normal amount of magnesium (0.2%). When the diet was sufficiently supplemented with magnesium (H1Mg diet), the development of hypertension was significantly slowed and the heart rate slightly lowered. With dietary magnesium depletion (LMg diet), the heart rate was accelerated and hypertension developed more rapidly. Excretion of urinary electrolytes (calcium, magnesium, and sodium) was increased by rats fed the H1Mg diet and decreased by rats on the LMg diet. Urinary cAMP was decreased both on the HMg diets and on the LMg diet. With the H1Mg diet, total and ionized calcium and sodium levels in plasma fell, and magnesium plasma levels rose. Rats fed the LMg diet had increased total and ionized calcium and decreased magnesium plasma levels. These results show that dietary magnesium modifies the metabolism of calcium, sodium, magnesium, which can modulate the development of genetic hypertension.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719931

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

The effect of hypomagnesemia on renal concentrating ability was assessed in rats fed diets either low in magnesium or low in magnesium and calcium for 30 days. The rats fed a low-magnesium diet became hypomagnesemic (0.26 +/−0.03 versus 1.53 +/−0.04 mEq/L in controls), hypercalcemic (5.96 +/−0.04 versus 5.22 +/−0.11 mEq/L in controls), and hypokalemic (3.1 +/−0.1 versus 4.2 +/−0.4 mEq/L in controls) with decreased muscle content of potassium. Despite being hypomagnesemic, hypercalcemic, and potassium depleted, the rats had normal renal concentration ability (2499 +/−65 versus 2415 +/−119 mOsm/kg H2O in control). Those rats fed a diet low in both magnesium and calcium became hypomagnesemic (0.41 +/−0.08 versus 1.53 +/−0.04 mEq/L in controls) but were hypocalcemic. They also had normal renal concentrating ability (2399 +/−109 versus 2415 +/−119 mOsm/kg H2O in controls). It is concluded that hypomagnesemia does not decrease renal concentrating ability in rats. Furthermore, a normal concentrating ability demonstrated in hypomagnesemic rats, in spite of hypercalcemia and potassium depletion suggests that hypomagnesemia may ameliorate the deleterious effects of hypercalcemia and/or potassium depletion on renal concentrating ability.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719932

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

The determination of blood mononuclear cell magnesium content may be a predictor of total body magnesium status. Separation techniques employing Ficoll-Hypaque have been used for this assay; however, Hypaque contains a significant concentration of iodine that may be toxic to the cell membrane and affect the results. We developed a different separation technique using arabinogalactan (Stractan) at concentrations of 13.0 and 17.7%. The blood from 16 normal volunteers was divided and assayed for mononuclear cell magnesium content using both methods. The results (mean +/−standard deviation) with the Ficoll-Hypaque method were 83.6 +/−30.8 fg/cell, and with the arabinogalactan method they were 78.4 +/−25.5 fg/cell. A paired sample t test comparing the results between the two methods gave a t value of 1.05 (P greater than .3). The purest population of blood mononuclear cells was obtained with the Ficoll-Hypaque method. Thus, these two separation materials do not have a significant effect on the blood mononuclear cell magnesium content, and the better separation of cells was obtained with Ficoll-Hypaque.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719933

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

It has been postulated that vitamin E compounds (tocopherols) can retard the aging process. Therefore, changes in concentrations of tocopherols in human plasma and platelets with aging were studied. Fasting blood samples were obtained from 48 healthy male volunteers aged 24-91 years. Concentrations of the tocopherols in plasma and platelets were determined by a liquid chromatographic method. Alpha and gamma tocopherols were the major forms of vitamin E found in both plasma and platelets. The concentrations of alpha and total tocopherols in plasma did not change significantly with age. However, the plasma gamma tocopherol and the platelet alpha, gamma, and total tocopherol concentrations decreased significantly with age. The platelet to plasma ratios of tocopherol concentrations also decreased with age.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719934

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

This investigation intended to clarify the effects of malnutrition in utero on enzymes of glycerol metabolism and the stores of phosphorylated glycerol intermediates in liver, striated muscle, and brain in the rat. Pregnant Wistar rats were restricted to an intake of 50% (M) of ad libitum fed controls (C) from the seventh day of gestation onward. Fetuses were removed 2 days (−2), or 1 day (−1), before term, or at the day of birth (DOB) The M fetuses and newborn rats were stunted. Their hepatic alpha-glycerophosphate oxidase (GPO) levels were lower than those of C in utero (mean +/−SEM: M = 23.1 +/−1.5, 15.8 +/−1.1, and 31.6 +/−4.5; C = 34.8 +/−4.9, 39.8 +/−7.0, and 23.6 +/−5.0 nmol/min×cm at -2, -1, and DOB, respectively; F = 7.29 [1,57], P less than .01). In muscle, this enzyme, as well as liver and brain alpha-glycerophosphate dehydrogenase (GPD), alpha-glycerophosphate (GP), and dihydroxyacetone phosphate (DHAP), only varied with the developmental stage. Although the latter was a significant differential factor in all the determinations, maternal diet only affected brain DHAP stores (M = 1.85 +/−0.36, 1.03 +/−0.16, 0.74 +/−0.10; C = 2.33 +/−0.46, 1.87 +/−0.21, 1.13 +/−0.18 mumol/g at -2, -1, and DOB, respectively; F = 9.03 [1,53], P less than .01). These findings support the contention that intrauterine malnutrition can alter normal ontogenesis of glycerol metabolism enzymes in certain organs and become a negative factor disturbing normal gluconeogenesis and glycogenolysis, with potential disruption of energy homeostasis immediately after birth.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719935

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

Dietary magnesium intakes and concentrations of magnesium in plasma and erythrocytes were determined in 23 lactating and 13 nonlactating healthy pregnant women from 37 wk of gestation through 6 mo postpartum. Food composites, collected for 3 days, were analyzed for magnesium, and energy intake was calculated from 3-day dietary records. The lactating women consumed significantly greater (P less than .05) amounts of magnesium and energy than the nonlactating women. Mean postpartum intake of magnesium was 55% of the recommended dietary allowance (RDA) for lactating women and 48% of the RDA for nonlactating women. Neither lactation nor length of lactation significantly affected plasma magnesium concentration or erythrocyte magnesium concentration. Dietary magnesium intake was not significantly correlated with the level of magnesium in either the plasma or erythrocytes.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719936

出版商:Routledge    

年代:1983

数据来源: Taylor

摘要:

Standard anthropometric techniques may be unreliable in patients with subcutaneous edema or dehydration. In order to circumvent this dilemma, 98 male subjects were studied utilizing a hand-held dynamometer in conjunction with other nutritional assessment techniques. Following a nutritional assessment using anthropometric measurements, patients were characterized as being well-nourished or malnourished using three definitive measures: percentage of ideal body weight, triceps skinfold, and midarm muscle circumference. Once malnutrition was assessed, no attempt was made to distinguish between marasmus, hypoalbuminemia, or mixed marasmus types of malnutrition. A correlation matrix done between the two groups revealed no statistically significant correlation between any of the measured parameters. Analysis of variance revealed statistically significant correlations between patients in both groups (independent variables) with respect to midarm muscle circumference and dynamometer reading in the dominant arm (dependent variables). Further validation of this technique is required before it can become a standard component of nutritional assessment.

ISSN:0731-5724    

DOI:10.1080/07315724.1983.10719937

出版商:Routledge    

年代:1983

数据来源: Taylor