---

Background: Hyperhomocysteinemia is an independent risk factor for cardiovascular disease (CVD) and especially atherosclerosis. Frequency of hyperhomocysteinemia in hemodialysis patients is higher than the general population. Thus near to 50 percent of the patients die due to CVD. The objective of this study is to determine the frequency of hyperhomocysteinemia in hemodialysis patients receiving 5 mg/d oral folic acid supplements in Imam Hossein hospital in Tehran. Materials and methods: In this cross-sectional study, plasma total homocysteine (tHcy) and serum folic acid and vitamin B12 were measured in 40 hemodialysis patients receiving 5 mg/d folic acid supplements from at least three months before. Correlation between these three factors and their correlation with other confounders were determined using non-parametric tests. Dietary intake of B vitamins related to tHcy metabolism, were assessed using 24 hour recall method for 3 consecutive days. Results: Median (median ± IQR) of plasma tHcy and serum folic acid and vitamin B12 were 20.95 ±12.17 µmol/l, 101.55 ± 113.92 ng/ml, 945 ± 526.5 pg/ml relatively. 75% of patients had high values for tHcy, 15% borderline values and only 10% normal values. Respectively,12.5% and 37.5% were in normal range of serum folic acid and vitamin B12 and 87.5 % and 62.5% had abovenormal levels. There was a significant, negative correlation between plasma tHcy and height , serum folic acid and dietary intake of vitamins B6 and B2. Mean tHcy levels were higher in women than in men. The correlation between plasma tHcy and other factors, like age, dialysis duration, dialysis efficiency, cigarette smoking, tea and coffee consumption, menopausal status, diagnosed diabetes mellitus, hypertension and hyperlipidemia, albumin, creatinin, urea and dietary intake of folic acid and vitamin B12 was not significant. Conclusion: Despite supplementation with folic acid, only a small proportion of patients reached normal levels of homocysteine. This, shows the necessity of supplementation with higher doses of folic acid combined with other B-vitamins like B12 and B6. Elevated serum level of folic acid is probably due to the effect of uremic environment on intracellular availability of folic acid. High level of serum B12 is the result of it's restricted conversion to the active form, in the most important conversion site, the kidneys.

---

Background and Objectives: A deficiency of folate or vitamin B12, particularly in tissues with a high cell replication rate, could inhibit RNA and DNA synthesis, DNA methylation, as well as cell maturation. Therefore, a sufficient intake of these vitamins in childhood is of vital importance. Since there are no published reports on the status of folic acid and vitamin B12 in Iranian children, the present study was conducted to assess serum and red blood cells concentrations and some related factors in healthy 3-6 year-old children in Tehran, Iran, 2010. Subject and Methods: This was a cross-sectional, descriptive-analytical study, in which 228 children, 3-6 year old (105 girls and 123 boys), were selected by random systematic cluster sampling from 20 (out of 270) day-care centers in Tehran. A 2-ml non-fasting blood sample was drawn from each child and analyzed for serum and red blood cell folate and vitaminB12 by the RIA method. SPSS.16 was used for data analysis, the statistical tests being t-test, Chi-square and ANOVA. Results: There were no significant differences between the 2 sexes with regard to age, weight, height, BMI, RBC folate, or serum folate and vitamin B12 levels. Based on the serum folate level, 9.6% and 37.8% of the children suffered from severe and mild deficiency, respectively 52.6% had normal folate serum levels. The data also showed that 97.4% of the children had a normal serum vitamin B12 level, only 2.6% being mildly deficient. As judged by the RBC folate level, of 105 children (60 boys and 45 girls), 1% and 37% had severe and mild deficiency, respectively, an absolute majority (62%) having normal levels. The distributions of serum folate, serum vitaminB12, and RBC folate levels were not statistically different between boys and girls. Similarly, no associations were observed between the RBC folate level, serum folate level, or serum vitamin B12 level and age, weight, height, family size, birth order, or head of the family. There were positive significant correlations between serum folate on the one hand and RBC folate (r=0.4 , p<0.001) and serum vitamin B12 (r=0.8 , p<0.001) on the other hand. Furthermore, folate, RBC folate, and serum vitamin B12 were all positively related to father’s education (p=0.01), mother's education (p=0.008) and father’s job status (p<0.027). In addition, the vitamin levels were higher in children of the working mothers, as compared to those of non-working mothers (p<0.036). There were no differences between the 2 groups with regard to other variables. Conclusion: Folate deficiency is highly prevalent, while the deficiency of vitamin B12 is low, among Tehrani preschoolers. It is recommended to design and implement suitable intervention programs. Major components of such programs should be mothers’ nutrition education and improving family food consumption patterns with particular emphasis on optimum utilization of folate sources, particularly vegetables. Keywords: Folic acid, Vitamin B12, Preschoolers

---

Background and Objectives: Folic acid has emerged as a key nutrient for optimizing health. Impaired folic acid status has been identified as a risk factor for cardiovascular disease, various types of cancers, and neurocognitive disorders. The study aimed to assess folic acid status and some related factors in female students of a medical university in Tehran, Iran. Materials and Methods: In this cross-sectional, descriptive-analytical study, 346 female students were randomly selected from eight schools of Shahid Beheshti University of Medical Sciences. For each student, questionnaires about general characteristics and their knowledge in folic acid intake were completed. Serum folic acid concentrations were measured by Radio Immunoassay (RIA). Dietary folic acid intake was assessed by 3 days food recall questionnaire. These data were analyzed by Food Processor (FP). Results: Based on the serum folate level, 3.5% and 32.7% of the students suffered from severe and mild deficiency, respectively. 63.8% had normal folate serum levels. Approximately 93% of students did not meet the reference dietary intake for folic acid (400 μg/day). Half of the students had good or excellent knowledge about folic acid and its properties. However, folic acid knowledge was not related to its intake. No correlation was found between folic acid concentrations in serum with folic acid intake from food. The serum folic acid concentrations were higher in multivitamin/ mineral supplement users than in non-users (p<0.0001). Conclusions: Folic acid deficiency is highly prevalent among students. Considering the importance of folic acid in health maintenance, appropriate intervention is necessary for adequate intake of folate. Keywords: Folic acid, Knowledge, Female Students

---

Background and Objectives: Folate is essential to cell division and growth. Folic acid is commonly measured using HPLC-MS, spectroscopy, ELISA, and microbial methods that are cost-intensive and time-consuming because they require long extraction and purification times. It is known that electrochemical methods are simple and inexpensive and that analytical techniques require a small sample size. Biosensors also have higher selectivity than other sensors. Materials and Methods: The present study proposes an electrochemical DNA biosensor as a screening device for rapid analysis of folic acid using a pencil graphite electrode modified with salmon sperm ds-DNA. Solution pH, DNA concentration, time of DNA deposition, and potential deposition were optimized using RSM. The binding of folic acid to DNA immobilized on a pencil graphite electrode was then measured using variations in the electrochemical signal of adenine. This biosensor was successfully used to measure folic acid in real samples, such as flour and spinach. Results: The optimum values for the reaction were pH of 4.8, DNA concentration of 24 μg mL−1, deposition time of 304 s, and deposition potential of 0.60 V, which produced an adenine signal of 3.04 μA. The folic acid concentration showed a linear correlation with the adenine signal current at 0.1–10.0 μM L−1 with a detection limit of 1.06×10−8 μM L−1. Conclusions: The results showed that the DNA-based biosensor showed high sensitivity, selectivity, and speed of folic acid determination. Keywords: Folic acid, Electrochemical, Biosensor, DNA, Selectivity