1,721,039 research outputs found
Gene interactions observed with the HDL-c blood lipid, intakes of protein, sugar and biotin in relation to circulating homocysteine concentrations in a group of black South Africans
Full text linkBackground: Elevated homocysteine (Hcy) is associated with several pathologies. Gene–diet interactions related to Hcy might be used to customize dietary advice to reduce disease incidence. To explore this possibility, we investigated interactions between anthropometry, biochemical markers and diet and single-nucleotide polymorphisms (SNPs) in relation to Hcy concentrations. Five SNPs of Hcy-metabolizing enzymes were analyzed in 2010 black South Africans. Results: Hcy was higher with each additional methylenetetrahydrofolate reductase (MTHFR) C677T minor allele copy, but was lower in methionine synthase (MTR) 2756AA homozygotes than heterozygotes. Individuals harboring cystathionine β synthase (CBS) 833 T/844ins68 had lower Hcy concentrations than others. No interactive effects were observed with any of the anthropometrical markers. MTHFR C677T and CBS T833C/844ins68 homozygote minor allele carriers presented with lower Hcy as high density lipoprotein cholesterol (HDL-c) increased. Hcy concentrations were negatively associated with dietary protein and animal protein intake in the TT and TC genotypes, but positively in the CC genotype of CBS T833C/844ins68. Hcy was markedly higher in TT homozygotes of MTHFR C677T as added sugar intake increased. In CBS T833C/844ins68 major allele carriers, biotin intake was negatively associated with Hcy; but positively in those harboring the homozygous minor allele. Conclusions: The Hcy–SNP associations are modulated by diet and open up the possibility of invoking dietary interventions to treat hyperhomocysteinemia. Future intervention trials should further explore the observed gene–diet and gene–blood lipid interactions.</p
Determination of folic acid in human plasma using hydrophilic interaction chromatography-tandem mass spectrometry
No full textFolic acid is an essential nutrient, and folate deficiency is associated with a variety of disorders including neural tube defects (during pregnancy) and heart disease. A fast, sensitive, and robust HPLC-tandem mass spectrometry (LC-MS-MS) method was developed for the quantification of free folic acid, tetrahydrofolate, 5'-methyltetrahydrofolate, and 5'-formyltetrahydrofolate in human plasma. Sample preparation required only acetonitrile precipitation of proteins followed by filtration instead of solid-phase extraction or solvent-solvent extraction as in other methods. The rapid and streamlined sample handling procedure minimized degradation of the highly unstable folate species. Hydrophilic interaction chromatography was used for additional sample cleanup on-line, and baseline separation and detection of all four folate species was achieved in less than 30 min. The folate species were detected using negative ion electrospray-tandem mass spectrometry with multiple reaction monitoring of the diagnostic fragment ions of each deprotonated molecule. The predominately organic (hydrophobic) solvent system combined with the microbore flow rate (50 L/min) used for the chromatography resulted in enhanced electrospray signal response compared to reversed-phase HPLC using a wider bore column. The recovery of all folate species (from spiked plasma) was >97␘ver a concentration range from 300 pg/L to 12 mg/L with intraday precision (RSD, n = 5) of 3.7-6.5ÐStability studies were carried out for spiked samples in order to define storage and handling conditions. The folic acid limit of quantification (LOQ) in human plasma was 80 pmol/L ± 10°and the limit of detection (LOD) was 37.5 pmol/L. The LOQ and LOD for tetrahydrofolate, 5'-methyltetrahydrofolate, and 5'-formyltetrahydrofolate were 1250, 400, and 360 pmol/L of plasma and 425, 165, and 140 pmol/L of plasma, respectively
Association between consuption of black tea and iron status in adult Africans in the North West Province: the THUSA study
No full textBioavailability of Micronutrients From Nutrient-Dense Whole Foods: Zooming in on Dairy, Vegetables, and Fruits
No full textIn order to fully exploit the nutrient density concept, thorough understanding of the biological activity of single nutrients in their interaction with other nutrients and food components from whole foods is important. This review provides a narrative overview of recent insights into nutrient bioavailability from complex foods in humans, highlighting synergistic and antagonistic processes among food components for two different food groups, i.e., dairy, and vegetables and fruits. For dairy, bioavailability of vitamins A, B2, B12 and K, calcium, phosphorous, magnesium, zinc and iodine are discussed, whereas bioavailability of pro-vitamin A, folate, vitamin C and K, potassium, calcium, magnesium and iron are discussed for vegetables and fruits. Although the bioavailability of some nutrients is fairly well-understood, for other nutrients the scientific understanding of uptake, absorption, and bioavailability in humans is still at a nascent stage. Understanding the absorption and bioavailability of nutrients from whole foods in interaction with food components that influence these processes will help to come to individual diet scores that better reflect absorbable nutrient intake in epidemiologic studies that relate dietary intake to health outcomes. Moreover, such knowledge may help in the design of foods, meals, and diets that aid in the supply of bioavailable nutrients to specific target groups
A dual-isotope-labeling method of studying the bioavailability of hexaglutamyl folic acid relative to that of monoglutamyl folic acid in humans by using multiple orally administered low doses
No full textThe Effect of Prebiotic Galacto-Oligosaccharides on Iron Absorption from Oral Iron Salts in Young Iron-Depleted Women
No full textIodine deficiency: Achievements and challenges for the 21st century
No full textIodine deficiency impairs the production of thyroid hormones, which has severe health consequences for child growth and development. Iodine deficiency is the most common cause of preventable mental impairment (Walker et al. in Lancet 369:145-57, [44], Zimmermann in Clin Endocrinol (Oxf.) 75:287-8, [50]). Mass iodization of salt provides a cost-effective way to improve iodine intake, with annual costs estimated at US$0.02-0.05 per child (UNICEF in The State of the World's Children 2012: Children in an urban world, United Nations Children's Fund, New York [40]), and over time has tremendously reduced the prevalence of severe iodine deficiency disorders across the globe. It is not certain, however, whether the iodine requirements of pregnant and lactating women are sufficiently covered by salt iodization programs. Although in many industrialized countries iodine deficiency has been addressed for centuries, the problem is currently recurring in some countries. New WHO recommendations on reducing sodium intake may also contribute to this. In contrast, several countries are now struggling with excessive intake of iodine. In this chapter, the following issues are discussed: • What is the current global iodine status? • Should additional measures be taken to cover iodine requirements during pregnancy and lactation? • What are the causes of recurring iodine deficiency in industrialized countries, and what can we learn from this? • Will reduction of salt intake influence the effectiveness of salt iodization programs? • What measures should be taken to prevent excessive iodine intake? • How can iodization programs be monitored better?
What is causing anemia in young children and why is it so persistent? : O que causa anemia em crianças mais novas e por que ela é tão persistente?
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Iodine deficiency, thyroid function and hearing deficit: a review
Get PDFIodine deficiency affects an estimated 241 million school-aged children in the world. Little is known about iodine deficiency in relation to auditory function, except for the fact that deaf-mutism is one of the features of cretinism. In the present review, we documented the scientific knowledge on the role of iodine and hypothyroidism in the auditory system. We found that ear development and hearing function depend on thyroid hormones. Multiple pathways are involved in this, including both inner ear morphology as well as neurological processes. Conductive as well as sensorineural hearing loss is found in studies with animals that were rendered hypothyroidic. In humans, auditory impairment is reported frequently in relation to hypothyroidism, ranging from mild disturbances to severe handicap. Auditory impairment has been related more explicitly to congenital hypothyroidism than to acquired hypothyroidism. The critical period for thyroid function-related hearing maturation is the first and second trimesters of pregnancy. Although only a limited number of studies have directly investigated the relationship between iodine deficiency and auditory function, most studies point toward an association. However, evidence from good randomised controlled trials is lacking. Inclusion of auditory outcomes in iodine supplementation studies is therefore to be recommended, especially for trials in pregnancy. Hearing deficit is an invisible abnormality, but has major consequences for educational and social skills if not detected. In view of this, auditory impairment should be mapped in iodine-deficient areas in order to realistically estimate the magnitude of the problem
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