Serum Vitamin B12 (serum + vitamin_b12)

Distribution by Scientific Domains


Selected Abstracts


Dietary methionine intake and neural tube defects in Mexican-American women

BIRTH DEFECTS RESEARCH, Issue 6 2010
Anna Graham
Abstract BACKGROUND Nutrients other than maternal folic acid are also thought to play a role in preventing neural tube defects (NTDs). Evidence suggests that methionine interacts with folic acid and vitamin B12 in the methylation of contractile proteins involved in closing the neural folds. The role of dietary intake of methionine in NTD risk has not been specifically studied among Mexican Americans, a population with one of the highest prevalences of NTDs in the United States. METHODS We conducted a case,control study of 184 Mexican American women with NTD-affected pregnancies (case women) and 225 women with normal offspring (control women) who resided along the Texas-Mexico border. The average daily intakes of methionine were calculated from periconceptional food frequency questionnaire data. Women were categorized according to quartiles of daily methionine intake, based on the control mothers' distribution, and the risk for an NTD-affected pregnancy was calculated using the lowest quartile of intake as the referent. RESULTS With adjustment for income, body mass index, hyperinsulinemia, and diarrhea, the odds ratios for increasing quartile of methionine intake were: 0.95 (95% confidence interval [CI], 0.48,1.90), 0.92 (95% CI, 0.46,1.84), and 0.66 (95% CI, 0.30,1.45). Some evidence of interaction between dietary methionine and serum vitamin B12 was noted particularly at higher levels of both components. CONCLUSIONS This study was limited by a small sample size but examined this association in an exclusively Hispanic population. Results were suggestive of a potential protective effect for NTDs with increasing maternal dietary methionine intake. Birth Defects Research (Part A), 2010. © 2010 Wiley-Liss, Inc. [source]


The maternal Mediterranean dietary pattern is associated with a reduced risk of spina bifida in the offspring

BJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 3 2009
M Vujkovic
Objective, The objective of this study was to test the hypothesis whether a maternal dietary pattern is associated with the risk of spina bifida (SB) in the offspring. Design, Case,control study. Setting, Eight clinic sites in the Netherlands, 1999,2001. Sample, A total of 50 mothers of children with SB and 81 control mothers. Methods, Maternal food intakes were obtained by food frequency questionnaires at the standardised study moment of 14 months after the birth of the index child. Principal component factor analysis (PCA) and reduced rank regression (RRR) were used to identify dietary patterns. Main outcome measures, Maternal biomarkers were used as response measures in the RRR analysis and composed of serum and red blood cell (RBC) folate, serum vitamin B12 and total plasma homocysteine. The strength of the use of the dietary pattern in association with SB risk was estimated by odds ratios and 95% CI with the highest quartiles of the dietary pattern as reference. Results, A predominantly Mediterranean dietary pattern was identified by both PCA and RRR. Those dietary patterns were highly correlated (r = 0.51, P < 0.001) and characterised by joint intakes of fruit, vegetables, vegetable oil, alcohol, fish, legumes and cereals and low intakes of potatoes and sweets. We observed a significantly increased risk of SB offspring in mothers with a weak use of the Mediterranean dietary pattern, OR 2.7 (95% CI 1.2,6.1) and OR 3.5 (95% CI 1.5,7.9). The Mediterranean dietary pattern was correlated with higher levels of serum and RBC folate, serum vitamin B12 and lower plasma homocysteine. Conclusion, The Mediterranean dietary pattern seems to be associated with reduction in the risk of offspring being affected by SB. [source]


Clinical manifestations of infants with nutritional vitamin B12 deficiency due to maternal dietary deficiency

ACTA PAEDIATRICA, Issue 1 2009
E Zengin
Abstract Aim: In developing countries, nutritional vitamin B12 deficiency in infants due to maternal diet without adequate protein of animal origin has some characteristic clinical features. In this study, haematological, neurological and gastrointestinal characteristics of nutritional vitamin B12 deficiency are presented. Methods: Hospital records of 27 infants diagnosed in a paediatric haematology unit between 2000 and 2008 were evaluated retrospectively. Results: The median age at diagnosis was 10.5 months (3,24 months). All the infants were exclusively breast fed and they presented with severe nonspecific manifestations, such as weakness, failure to thrive, refusal to wean, vomiting, developmental delay, irritability and tremor in addition to megaloblastic anaemia. The diagnosis was confirmed by complete blood counts, blood and marrow smears and serum vitamin B12 and folic acid levels. The median haemoglobin level was 6.4 g/dL (3.1,10.6) and mean corpuscular volume (MCV) was 96.8 fL (73,112.3). Some patients also had thrombocytopaenia and neutropaenia. All the infants showed clinical and haematological improvement with vitamin B12 administration. Patients with severe anaemia causing heart failure received packed red blood cell transfusions as the initial therapy. Conclusion: Paediatricians must consider nutritional vitamin B12 deficiency due to maternal dietary deficiency in the differential diagnosis of some gastrointestinal, haematological, developmental and neurological disorders of infants with poor socioeconomic status. Delay in diagnosis may cause irreversible neurological damage. [source]


Serum homocysteine concentrations in children with growth hormone (GH) deficiency before and after 12 months GH replacement

CLINICAL ENDOCRINOLOGY, Issue 5 2004
Valentina Esposito
Summary objective, This open, prospective study was designed to evaluate the effect of growth hormone deficiency (GHD) and GH replacement therapy on serum homocysteine (Hcy) concentration in children with GHD. subjects, Seventeen prepubertal children with GHD (11 boys and six girls) aged 8·6 ± 1·9 years were studied before and after 12 months of GH replacement therapy at a dose of GH of 30 µg/kg/day. Seventeen healthy children acted as controls and were matched for age, sex and body mass index (BMI). methods, At study entry, height, weight, blood pressure, serum Hcy, serum IGF-I, total-low density lipoprotein (LDL)- and high density lipoprotein (HDL) cholesterol, triglycerides, free T4, free T3, vitamin B12, folate, glucose and creatinine were measured in all subjects. The atherogenic index (AI) was also calculated as the ratio of total cholesterol/HDL cholesterol (T/HDL). In GHD children these parameters were also revaluated after 12 months of GH therapy. results, At study entry height and serum IGF-I were significantly lower, as expected, in GHD patients than in controls (P < 0·0001 and P < 0·007, respectively). Serum Hcy levels were significantly higher in GHD patients than in healthy children (8·4 ± 2·9 vs. 6·0 ± 2·9 µmol/l; P < 0·03), although the absolute values were within the normal values for age and sex. There were no significant differences at baseline with respect to blood pressure, serum vitamin B12, folate, fT3, fT4, lipid profile, creatinine and glucose levels. After 12 months of GH replacement therapy height and serum IGF-I increased significantly compared to pretreatment values (P < 0·0001); serum Hcy levels decreased significantly (6·0 ± 3·3 µmol/l; P < 0·002) compared to baseline values, becoming similar to control values. Total cholesterol (3·5 ± 0·6 mmol/l) and the AI (2·5 ± 0·8) decreased significantly with respect to both pretreatment (4·2 ± 1·0 mmol/l; P < 0·0002 and 3·4 ± 0·8; < 0·002, respectively) and control values (4·2 ± 0·4 mmol/l; P < 0·0005 and 3·3 ± 1·1; P = 0·02, respectively). conclusions GHD in children is associated with higher serum levels of Hcy compared to controls, without significantly affecting the lipid profile. GH replacement for 12 months significantly decreased the Hcy levels and improved the lipid profile with a decrease of total cholesterol and the total/HDL cholesterol ratio, compared to pretreatment values. Given the small number of patients, further larger studies are needed to clarify whether these results may have significant effects in the prevention of cardiovascular disease in adulthood. [source]