Folate and vitamin B12 intake and risk of squamous-cell carcinoma of the esophagus

Esophageal cancer is one of the most common cancers in Iran and has a high mortality rate. The aim of this study was to assess the association between folate and vitamin B12 intake and risk of squamous-cell carcinoma of the esophagus cancer. In this case-control study, cases [n=47] were patients diagnosed with squamous-cell carcinoma of the esophagus [SCCE] in main hospital Kurdistan and controls [matched with cases by age and sex] were patients with acute non-cancer diseases at the same hospitals [n=96]. Demographic data and physical activity were collected using questionnaires. A semi-quantitative food frequency questionnaire used for nutritional information and folate and vitamin B12 intake were calculated with Nutritionst IV [N4]. Thirty eight percent of cases and 40% of controls were males. Mean age of cases and controls were 58 +/- 18 and 58 +/- 17 years respectively. Mean folate intake among cases was 152.1 microg/day, which was less than in the controls. After adjustment for confounders, folate intake was inversely related with SCCE [OR=0.03, 95% Cl 0.00, 0.12]. The association between vitamin B[12] intake and SCCE was not significant [p=0.46]. Folate intake was inversely related with SCCE: however, there was not a significant association between vitamin 612 intake and SCCE

Effects of cyanocobalamin on immunity in patients with pernicious anemia

The aim of the study was to evaluate the role of vitamin B12 in patients with pernicious anemia. This study was conducted prospectively at the Turgut ?zal Medical Center, Department of Hematology, between April and November 2002. Absolute numbers and ratio of the surface antigens of T and B lymphocyte subgroups, CD4/CD8 ratio were calculated in order to evaluate changes in leukocyte and lymphocyte numbers; natural killer [NK] cell count, serum C3, C4, and levels of immunoglobulins G, A, and M were also measured to evaluate vitamin B[12] effect on immunity. Values obtained before treatment with cyanocobalamin were compared with those found during peak reticulocyte count. In vitamin B[12]-deficient patients, absolute numbers of CD4+ and especially CD8+ lymphocytes were found to be decreased; CD4/CD8 ratio increased, and NK cell activity was depressed. After cyanocobalamin treatment, absolute numbers and percentage of lymphocyte subgroups were elevated. Increased CD4/CD8 ratio and depressed NK cell activity were restored and levels of C3, C4, and immunoglobulins were elevated. These findings suggest that vitamin B[12] has important immunomodulatory effects on cellular immunity, and abnormalities in the immune system in pernicious anemia are restored by vitamin B[12] replacement therapy

In vitro effect of folic acid and cobalamin [vitamin B12] on adhesion and growth of Giardia lamblia

Giardia lamblia is one of the most common intestinal protozoan parasites infecting human in the world. The goal of this study was searching for in-vitro effect of folic acid and cobalamin on adhesion and growth of G. lamblia as two important mechanisms in the pathogenesis in TYI-S-33 medium. G. lamblia trophozoites were obtained by in- vitro excystation procedure. Three groups of Giardia trophozoites were analyzed: control group, G.lamblia was cultured in TYI-S-33 without any vitamin, 2nd group with 0.1 micro g/ml vitamin B12 or folic acid, and 3rd group with 0.5 micro g/ml of vitamin B12 or folic acid. All culture media tubes incubated at 37 °C. After 2 h of incubation, the adherence into borosilicate culture tubes, and after 24 h the growth of trophozoites were measured .The results showed that in vitamin B12 groups, the growth was increased significantly [P? 0.05] but the adherence decreased significantly [P

Purification, relative molecular mass and subunits of thymidylate synthase from Lactobacillus leichmannii.

Thymidylate synthase (5, 10-methylenetetrahydrofolate: dUMP C-methyltransferase, EC 2.1.1.45) from crude cell extracts of Lactobacillus leichmannii has been purified 190-fold to homogeneity by chromatography on hydroxylapatite, DEAE-cellulose and Sephadex G-100 columns. It has UV absorption maxima at 280 nm. The crude extracts, however, have RNA associated with the native enzyme. This is in line with our earlier observation on the Streptococcus faecium thymidylate synthase [Narasimha Rao K & Kisliuk R L, (1983) Proc Natl Acad Sci USA, 80, 916-920]. Optimal conditions for dTMP synthase activity are: 275 microM (dl)-L-H4PteGlu, 13 mM HCHO, 13 mM MgCl2, 100 microM dUMP and 75 mM 2-mercaptoethanol at pH 7.4 using Tris-HCl buffer. The enzyme has M(r) of 74 kDa, Stokes radius of 1.24 nm and a sedimentation coefficient value of 0.45 S. The enzyme is a dimer composed of 2 identical subunits each with M(r) of 37 kDa.