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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A study of the platinum (II), palladium (II), and rhodium (III) chelates of aspartic and glutamic acid

Luschak, Cecilia Elizabeth 01 January 1964 (has links)
It is fairly well known that alpha-amino dicarboxylic acids combine quite readily with basic metal ions such as the alkaline earths. The nature of the problem includes the synthesis and characterization of six platinum metal chelates of two alpha-animo dicarboxylic acids, namely aspartic and glutamic acids. The metal ion upon which the investigation is focused are platinum (II), palladium (II), and rhodium (III). Several of these are reported as having been repaired. The series is incomplete, however, and little study has been done correlating the abilities and trends of the complexes as a function of the metal ion and carbon chain length of the ligand acid molecule. Hence, the ultimate aim of the investigation is to study the tendency of chelation as the carbon chain length of the alpha-amino dicarboxylic acid increases and also to study the stability of the chelates as the central metal ion is varied. Because there are numerous problems involved here, the investigation extends somewhat beyond the scope of a Master’s research. Therefore the investigation is limited only to aspartic and glutamic acid. The methods of synthesis for the palladium, platinum, and rhodium chelates of aspartic and glutamic acids were studied and outlined. After synthesis, the means which were employed for characterization included elemental analysis, molecular weight determination, and infrared and ultraviolet spectra.
2

Relative Absorption of Iron and Magnesium from Sulfate Salts, Amino Acid Chelates Complexed and/or Mixed with Vegetables, and Taste-Free Supplements

Bowden, Jennifer A. 01 May 1997 (has links)
Common methods for determining mineral absorption by the body are invasive and frequently utilize radioisotopes. In experiment one. rats were given a dose of radiolabeled ferrous sulfate. Relative absorption was estimated by changes in serum iron and by appearance of the radiotracer in the serum. There were no differences in relative absorption determined by the methods, although the low overall absorptions by the iron-replete rats may have decreased the sensitivity. In experiments two and three. iron and magnesium supplements were given orally to 12 women age 19-25. Each subject received iron and magnesium supplements once each week for 5 weeks. Blood samples were taken via venous catheter every 30 minutes for 2 hours and 30 minutes following dosing, and a urine sample was taken following the collection time period. Samples were analyzed for serum iron, serum magnesium, hematocrit, ferritin, urinary magnesium, and urinary creatinine. The increase in serum iron was evaluated from both the peak increase in serum iron and from the integrated increase in serum iron over the blood collection time. The data for each supplement were compared by analysis of variance. For the iron supplements. the taste-free iron supplement increased serum iron less than either the Ferrochel or the ferrous sulfate supplements. When the iron absorption was then compared to ferritin stores (low, medium, and high), the relative absorption of Ferrochel was higher in the low ferritin range (0-15 ng/ml) than in the upper ranges (P=.00l for peak and P=.0002 for area). Relative absorption from Ferrochel iron was also higher than the other supplements for subjects with low ferritin stores. Neither serum nor urinary magnesium values differed significantly among the three compounds examined. Serum magnesium values are stable in healthy individuals, and the urinary magnesium data were not evaluated over 24 h as in typical magnesium load tests. In summary, both the ferrous sulfate and Ferrochel supplements were absorbed more efficiently than the taste-free iron supplement. The Ferrochel was also absorbed more efficiently in individuals with low iron stores, demonstrating better regulation by the body than with the other supplements examined.
3

Availability of zinc from an amino acid chelate in Zn depleted pigs /

Swinkels, Johannes W. G. M., January 1992 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1992. / Vita. Abstract. Includes bibliographical references (leaf 140). Also available via the Internet.
4

Availability of zinc from an amino acid chelate in Zn depleted pigs

Swinkels, Johannes W. G. M. 06 June 2008 (has links)
This study was conducted to compare the availability of Zn from two Zn sources, an amino acid chelate and ZnSO₄. In three experiments, 78 Zn depleted and 24 Zn adequate pigs were used. Pigs were depleted of Zn by feeding an isolated soy protein, semi purified diet containing 17 ppm Zn. Of the 78 depleted pigs, 60 pigs were Zn repleted. During Zn repletion in Exp. 1, depleted pigs were fed the low Zn diet supplemented with 5, 15, or 45 ppm Zn either as ZnSO₄ or as Zn amino acid chelate (ZnAAC). In Exp. 2 and 3, low Zn diets were only supplemented with 45 ppm Zn. Zinc adequate pigs, used in Exp. 1 and 2, were fed the 45 ppm supplemental Zn diets. To evaluate differences in site and rate of apparent Zn absorption, chromic oxide was added to the diets of depleted pigs in Exp. 1 and 3. In all experiments, a 24-d period was sufficient to severely deplete the porcine body Zn stores, and to cause parakeratosis and growth retardation. Serum Zn concentrations and serum ALP-activities of depleted pigs dramatically decreased (P < .01) during the first 14 d of Zn depletion. At the end of Zn depletion, Zn contents in liver, kidney, pancreas, brain, and small intestine tissues of pigs fed the low Zn diet were reduced (P < .01) by 10 to 40 % compared with the adequate pigs fed the ZnSO₄ and ZnAAC diets. In Exp. 2, the growth retardation was associated with a low (P < .05) serum mitogenic activity and pituitary RNA content of depleted pigs compared with pair-fed adequate pigs. Moreover, the growth hormone mRNA fraction tended to be reduced (P < .10) for the Zn depleted pigs. In Exp. 1, the apparent absorption of Zn was higher (P < .01) for pigs fed ZnAAC compared with the ZnSO₄ group; however, this was not confirmed in Exp. 3 unless coefficients were corrected for Cr recovery. Furthermore, absorption of Zn occurred primarily within jejunal and distal segments of the small intestine. In the balance of Exp. 3, disappearance rates of Zn, Cu, Fe and DM were higher (P < .01) in depleted pigs fed ZnAAC compared with ZnSO₄. The recovery of Cr also was different (P < .01) between pigs fed the ZnSO₄ (87 %) and ZnAAC (70 %) diets. Moreover, the moisture content of the fecal matter was 11 % higher (P < .01) for the ZnAAC group compared with pigs fed ZnSO₄. In Exp. 1, depleted pigs fed the 15 ppm ZnSO₄ and ZnAAC diets regained their ability to grow, however, replenishment of body fluid and tissue Zn pools did not occur within the 24-d Zn repletion period. Both the 5 ppm ZnSO₄ and ZnAAC groups did not respond to Zn repletion within a 12-d period. In all experiments, the rate and degree of repletion of body fluid and tissue Zn stores was not different between pigs fed the 45 ppm ZnSOq and ZnAAC diets, although a higher (P < .05) serum mitogenic activity was observed for the adequate pigs fed ZnAAC compared with ZnSO4. In conclusion, an amino acid chelate did not improve growth, or rate and degree of replenishment of body fluid and tissue levels of Zn compared with pigs fed ZnSO₄. However, ZnAAC may have influenced intestinal luminal conditions since a higher rate of disappearance of Zn, Cu, Fe, Cr, and DM was measured. / Ph. D.

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