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101.
Evaluation of the effect of Ultra Rice® EDTA supplementation on the soluble iron,visual acceptance and vitamin A stability of commercial milled rice blends 下载免费PDF全文
Paul W. Johns Gaurav C. Patel Megan E. Parker John B. Lasekan Peiman Milani Melissa K. Nixon Maryann Tigner Daniel J. Schmitz 《International Journal of Food Science & Technology》2015,50(7):1615-1624
The addition of NaFeEDTA at only 5% of total iron to ferric pyrophosphate‐fortified Ultra Rice® increased the in vitro soluble iron ten‐fold. Ultra Rice® formulated with NaFeEDTA at 2–7% of total iron, or with Na2EDTA·2H2O at 0.5× the total iron equivalents, increased the soluble iron seven‐ to thirty‐fold. The colour of the batches was acceptable through 20 weeks at 21 °C, but colour stability needs to be evaluated under authentic storage conditions. Although only 34–46% of the initial vitamin A remained after extrusion, 18‐week storage at 30 °C/70% relative humidity, and simulated cooking, there were indications that losses could be decreased by raising the pH (to ~5) and/or using a better protected vitamin A ingredient. The enhancement of soluble iron afforded by low‐level NaFeEDTA or Na2EDTA·2H2O supplementation suggests that this fortification strategy may merit further study as a means of increasing absorbable iron in Ultra Rice®. 相似文献
102.
Alcantara EH Lomeda RA Feldmann J Nixon GF Beattie JH Kwun IS 《Molecular nutrition & food research》2011,55(10):1552-1560
Scope: Zinc is implicated as an activator for bone formation, however, its influence on bone calcification has not been reported. This study examined how zinc regulates the bone matrix calcification in osteoblasts. Methods and Results: Two osteoblastic MC3T3‐E1 cell subclones (SC 4 and SC 24 as high and low osteogenic differentiation, respectively) were cultured in normal osteogenic (OSM), Zinc deficient (Zn–, 1 μM), or adequate (Zn+, 15 μM) media up to 20 days. Cells (SC 4) were also supplemented with (50 μg/mL) or no ascorbic acid (AA) in combination with Zinc treatment. Zn– decreased collagen synthesis and matrix accumulation. Although AA is essential for collagen formation, its supplementation could not compensate for Zinc deficiency‐induced detrimental effects on extracellular matrix mineralization. Zn– also decreased the medium and cell layer alkaline phosphatase ALP activity. This decreased ALP activity might cause the decrease of Pi accumulation in response to Zn–, as measured by von Kossa staining. Ca deposition in cell layers, measured by Alizarin red S staining, was also decreased by Zn–. Conclusion: Our findings suggest that zinc deprivation inhibits extracellular matrix calcification in osteoblasts by decreasing the synthesis and activity of matrix proteins, type I collagen and ALP, and decreasing Ca and Pi accumulation. Therefore zinc deficiency can be considered as risk factor for poor extracellular matrix calcification. 相似文献
103.
Nuclear-encoded proteins target to the plastid in Toxoplasma gondii and Plasmodium falciparum 总被引:1,自引:0,他引:1
RF Waller PJ Keeling RG Donald B Striepen E Handman N Lang-Unnasch AF Cowman GS Besra DS Roos GI McFadden 《Canadian Metallurgical Quarterly》1998,95(21):12352-12357
A vestigial, nonphotosynthetic plastid has been identified recently in protozoan parasites of the phylum Apicomplexa. The apicomplexan plastid, or "apicoplast," is indispensable, but the complete sequence of both the Plasmodium falciparum and Toxoplasma gondii apicoplast genomes has offered no clue as to what essential metabolic function(s) this organelle might perform in parasites. To investigate possible functions of the apicoplast, we sought to identify nuclear-encoded genes whose products are targeted to the apicoplast in Plasmodium and Toxoplasma. We describe here nuclear genes encoding ribosomal proteins S9 and L28 and the fatty acid biosynthetic enzymes acyl carrier protein (ACP), beta-ketoacyl-ACP synthase III (FabH), and beta-hydroxyacyl-ACP dehydratase (FabZ). These genes show high similarity to plastid homologues, and immunolocalization of S9 and ACP verifies that the proteins accumulate in the plastid. All the putatively apicoplast-targeted proteins bear N-terminal presequences consistent with plastid targeting, and the ACP presequence is shown to be sufficient to target a recombinant green fluorescent protein reporter to the apicoplast in transgenic T. gondii. Localization of ACP, and very probably FabH and FabZ, in the apicoplast implicates fatty acid biosynthesis as a likely function of the apicoplast. Moreover, inhibition of P. falciparum growth by thiolactomycin, an inhibitor of FabH, indicates a vital role for apicoplast fatty acid biosynthesis. Because the fatty acid biosynthesis genes identified here are of a plastid/bacterial type, and distinct from those of the equivalent pathway in animals, fatty acid biosynthesis is potentially an excellent target for therapeutics directed against malaria, toxoplasmosis, and other apicomplexan-mediated diseases. 相似文献
104.
The equilibrium swelling behavior of end-linked silicone networks has been studied, using low molecular weight silicone oils as diluents. Using the phantom and affine versions of the Flory–Rehner elasticity theory, the predictability of the equilibrium swelling has been examined. It was found that a modified version of the Flory–Rehner equation can be used to predict the equilibrium swelling behavior, provided the interaction parameter is known or measured. The modification is the use of the measured elastic shear modulus of the network prior to swelling, to calculate the density of network chains needed in the equation for swelling. This implies that both entangled and chemically linked chains contribute to the swelling behavior, since the modulus itself is predicted by the use of an equation that incorporates the contribution of entanglements. © 1994 John Wiley & Sons, Inc. 相似文献
105.
Although rarely considered, siblings may significantly affect families in ways that have implications for other children's functioning, especially when the siblings' problems pose special difficulties. This study examined how having a disabled sibling predicted children's reactions to the everyday stress of family-related conflicts. Thirty children with a disabled sibling (15 boys, 15 girls) and 30 with nondisabled siblings (15 boys, 15 girls) responded to a series of disputes involving other family members. Having a disabled sibling predicted sensitization to these everyday family stresses, including more emotional distress; more expected involvement, perceived threat, and personal responsibility; more active coping strategies; and lower thresholds of conflict intensity for responding. Children with disabled siblings also evidenced more adjustment problems. Although developmental outcomes of challenging family circumstances may vary considerably for individual children, these results demonstrate the potential significance of siblings to the functioning of other children in the family. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
106.
107.
108.
DW Nixon 《Canadian Metallurgical Quarterly》1976,136(10):1117-1118
Three patients developed different nail color alterations after they had received chemotherapy for cancer. Many anticancer drug combinations are associated with similar findings. Transverse pigmented bands are most common, and these changes should not be confused with those attributable to systemic disease. 相似文献
109.
110.
The antigenic activity of angiotensin and its seven fragments has been studied in cross-reaction with specific antibodies, elicited to angiotensin and its fragments: C-terminal hexapeptide and middle tetrapeptide. It has been found that all the fragments studied possess certain affinity for antibodies elicited to angiotensin, C-terminal hexapeptide and middle tetrapeptide. The middle tetrapeptide was identified to be the immunologically active centre of the angiotensin molecule. 相似文献