Clinical Medicine (Scholarly Publications): Recent submissions
Now showing items 601-620 of 648
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Screening for vitamin B-12 and folate deficiency in older persons
(American Society for Clinical Nutrition, 2003)Background: Vitamin B-12 deficiency is usually accompanied by elevated concentrations of serum total homocysteine (tHcy) and methylmalonic acid (MMA). Folate deficiency also results in elevated tHcy. Measurement of these ... -
Genetic and nutritional factors contributing to hyperhomocysteinemia in young adults
(The American Society of Hematology, 2003)A modestly elevated total plasma homocysteine concentration (tHcy) is generally accepted as an independent and graded risk factor for various pathologies, including vascular diseases, neural tube defects, Alzheimer disease, ... -
RAD51 135G>C modifies breast cancer risk among BRCA2 mutation carriers: Results from a combined analysis of 19 studies
(The American Society of Human Genetics, 2007)Though much progress has been made in understanding the role of two major high-risk breast cancer (BC) susceptibility genes, BRCA1 and BRCA2, it remains unclear what causes the observed variation in risk between mutation ... -
The short-term bioavailabilities of [6S]-5-methyltetrahydrofolate and folic acid are equivalent in men.
(The American Society for Nutritional Sciences, 2004)The natural folate derivative, 5-methyltetrahydrofolate ([6S]-5-MTHF), could be an option for supplementation and fortification but its bioavailability remains unclear. This study compared the bioavailability of [6S]-5-MTHF ... -
A common insertion/deletion polymorphism of the thymidylate synthase (TYMS) gene is a determinant of red blood cell folate and homocysteine concentrations
(Springer, 2005)Substantial evidence suggests that a low folate/high homocysteine phenotype is pathogenic. We analyzed the impact of the thymidylate synthase (TYMS) 3UTR ins/del polymorphism on folate and homocysteine levels and assessed ... -
Evidence of unmetabolised folic acid in cord blood of newborn and serum of 4-day-old infants
(Cambridge University Press, 2007)Oral folic acid above certain threshold doses results in unmetabolised folic acid in serum. This raises a number of public health safety issues, principally the potential to mask pernicious anaemia; more recently the ... -
Postprandial serum folic acid response to multiple doses of folic acid in fortified bread
(Cambridge University Press, 2006)The benefit of the introduction of mandatory folic acid fortification of all flour products in the USA in 1998 has been amply demonstrated in a reduction of neural tube defect births. Doubt has been cast on the actual level ... -
The rate of intestinal absorption of natural food folates is not related to the extent of folate conjugation
(American Society for Nutrition, 2006)Background: Evidence is conflicting as to whether the bioavailability of food folates is influenced by the extent of their conjugation. Objective: The objective was to compare the bioavailability of 3 representative ... -
Folic acid fortification and public health: report on threshold doses above which unmetabolised folic acid appear in serum
(2007)Background All flour in the USA is fortified with folic acid at a level of 140 ?g/100 g which is estimated to supply an extra 100 ?g daily to the average diet. Some researchers have advocated that this be increased to ... -
A polymorphism, R653Q, in the trifunctional enzyme methylenetetrahydrofolate dehydrogenase/methenyltetrahydrofolate cyclohydrolase/formyltetrahydrofolate synthetase is a maternal genetic risk factor for neural tube defects: report of the Birth Defects Research Group
(2002)Women who take folic acid periconceptionally reduce their risk of having a child with a neural tube defect (NTD) by >50%. A variant form of methylenetetrahydrofolate reductase (MTHFR) (677C?T) is a known risk factor for ... -
Impact of the MTHFR C677T polymorphism on risk of neural tube defects:case-control study
(BMJ, 2004)Homozygosity for the T allele of the C677T polymorphism of the gene encoding the folate dependent enzyme 5,10-methylenetetrahydrofolate reductase (MTHFR) is a risk factor for neural tube defects.1 Both the homozygous (TT) ... -
Maternal homocysteine before conception and throughout pregnancy predicts fetal homocysteine and birth weight.
(American Association for Clinical Chemistry, 2004)BACKGROUND: Increased homocysteine has been associated with pregnancy complications. METHODS: We investigated prospectively the effect of maternal homocysteine on normal pregnancy outcome. The study included 93 women and ... -
Determining bioavailability of food folates in a controlled intervention study
(2004)Background: The concept of dietary folate equivalents (DFEs) in the United States recognizes the differences in bioavailability between natural food folates and the synthetic vitamin, folic acid. However, many published ... -
A polymorphism in the MTHFD1 gene increases a mother's risk of having an unexplained second trimester pregnancy loss.
(Oxford University Press, 2005)Low maternal folate or vitamin B12 status has been implicated in numerous pregnancy complications including spontaneous abortion. The primary aim of this study was to test a polymorphism within the trifunctional folate ... -
Choline and homocysteine interrelations in umbilical cord and maternal plasma at delivery.
(American Society for Clinical Nutrition, 2005)Background: Little is known about the interactions between choline and folate and homocysteine metabolism during pregnancy despite the facts that pregnancy places considerable stress on maternal folate and choline stores ... -
Riboflavin lowers homocysteine in individuals homozygous for the MTHFR 677C->T polymorphism.
(2006)Background? Meta-analyses predict that a 25% lowering of plasma homocysteine would reduce the risk of coronary heart disease by 11% to 16% and stroke by 19% to 24%. Individuals homozygous for the methylenetetrahydrofolate ... -
Confirmation of the R653Q polymorphism of the trifunctional C1-synthase enzyme as a maternal risk for neural tube defects in the Irish population.
(Nature Publishing Group, 2006)The risk of neural tube defects (NTDs) is known to have a significant genetic component that could act through either the NTD patient and/or maternal genotype. The success of folic acid supplementation in NTD prevention ... -
Clinical relevance of low serum vitamin B12 concentrations in older people: the Banbury B12 study.
(Oxford University Press, 2006)BACKGROUND: low vitamin B12 concentrations are common in older people, but the clinical relevance of biochemical evidence of vitamin B12 deficiency in the absence of anaemia is uncertain. OBJECTIVE: to examine associations ... -
Detection of vitamin B12 deficiency in older people by measuring vitamin B12 or the active fraction of vitamin B12, holotranscobalamin.
(American Association for Clinical Chemistry, 2007)Background: Impaired vitamin B12 function and decreased vitamin B12 status have been associated with neurological and cognitive impairment. Current assays analyze total vitamin B12 concentration, only a small percentage ... -
Longitudinal study of the effect of pregnancy on maternal and fetal cobalamin status in healthy women and their offspring.
(2007)Compromised cobalamin status during pregnancy may put both mother and child at risk of deficiency during lactation and subsequent development. We investigated whether changes in cobalamin status during pregnancy are ...
