Total Vitamin B12 Research Articles

Oatmeal consumption is associated with increased nutrient intake, better diet quality, and lower body mass index in adult participants (19+ y) from the NHANES (2001‐2010) (810.12)

The association between oatmeal consumption with nutrient intake, dietary quality, and body weight parameters was examined in adults (n=22,823) using data from NHANES (2001‐2010). Consumers (n=1,419) were defined as having any amount of oatmeal during a 24‐hour diet recall. ANOVA (covariate adjusted) were conducted using appropriate sample weights. Diet quality was calculated using the Healthy Eating Index‐2005 (HEI). Energy adjusted protein (87±1.3 v 83±0.3 g/d), dietary fiber (20.5±0.3 v 15.8±0.1 g/d), vitamin A (826±24 v 610±7 RAE µg/d), Ca (1041±20 v 927±6 mg/d), P (1488±16 v 1351±5 mg/d), Mg (361±6 v 289±1 mg/d), Fe (17.0±0.2 v 15.5±0.1 mg/d), and K (2958±34 v 2714±12 mg/d) intake were higher (p<0.01) in consumers than non‐consumers. Total fat (75±0.6 v 83±0.3 g/d), SFA (24.3±0.3 v 27.2±0.1 g/d), cholesterol (239±6 v 290±2 mg/d), and vitamin B12 (4.4±0.1 v 5.5±0.1 µg/d) were lower in consumers. Consumers had higher HEI scores (58.9±0.5 v 50.6±0.2) due to more whole grains (2.7±0.06 v 0.6±0.01 cup eq/d) and less SFA, solid fat (39.0±0.6 v 46.1±0.2 g/d), and added sugars (17.2±0.5 v 19.3±0.2 tsp/d). BMI (27.5±0.3 v 28.5±0.1) and waist circumference (94.9±0.5 v 97.5±0.2 cm) were lower in consumers. Consumers were 25% less likely to be overweight or obese and had a 21% reduced risk of increased waist size. Oatmeal consumption was associated with better nutrient intake, diet quality, and weight parameters in adults.Grant Funding Source: PepsiCo

Lipid and non-lipid cardiovascular risk factors in postmenopausal type 2 diabetic women with and without coronary heart disease

Coronary heart disease (CHD) is the leading cause of death in diabetic women. In addition to hyperglycemia, other factors may contribute to the excessive cardiovascular risk. In this study we evaluated common and emerging risk factors in a selected group of postmenopausal type 2 diabetic women with (n = 36) and without CHD (n = 59), not taking lipid-lowering medications. Clinical and lifestyle data were collected, and metabolic and lipid profile, as well as fasting plasma levels of total homocysteine (tHcy), folate, vitamin B12, C-reactive protein (hsCRP), interleukin 6 (IL-6), and vascular cell adhesion molecule-1 (VCAM-1) were measured in all participants. Age, menopause and diabetes duration, family history for cardiovascular disease, prevalence of hypertension and current insulin use were greater in diabetic women with than without CHD (P < 0.05 for all comparisons). CHD women also showed higher levels of triglycerides, small dense LDL (sdLDL), remnant-like particle cholesterol, tHcy, and VCAM-1, and a lower creatinine clearance (P < 0.05 all). Conversely, the two groups were comparable for BMI, waist circumference, smoking habit, fasting plasma glucose, HbA1c, total cholesterol, low-density lipoprotein cholesterol (LDL-C), HDL cholesterol, folate, vitamin B12, hsCRP and IL-6 levels. At multivariate analysis, lower creatinine clearance (OR = 0.932, P = 0.017) and higher sdLDL serum concentration (OR = 1.224, P = 0.037) were the strongest risk factors associated with CHD in this population, whereas no significant association was noted with LDL-C. Our data suggest that beyond LDL-C, a lower creatinine clearance and more subtle alterations of LDL particles, together with a constellation of several well known and emerging cardiovascular risk factors, are stronger contributors to the high CHD risk of diabetic women.

Evaluation of vitamin B6 intake and status of 20- to 64-year-old Koreans.

BACKGROUND/OBJECTIVESRecent research regarding vitamin B6 status including biochemical index is limited. Thus, this study estimated intakes and major food sources of vitamin B6; determined plasma pyridoxal 5'-phosphate (PLP); and assessed vitamin B6 status of Korean adults.MATERIALS/METHODSThree consecutive 24-h diet recalls and fasting blood samples were collected from healthy 20- to 64-year-old adults (n = 254) living in the Seoul metropolitan area, cities of Kwangju and Gumi, Korea. Vitamin B6 intake and plasma PLP were analyzed by gender and by vitamin B6 supplementation. Pearson's correlation coefficient was used to determine associations of vitamin B6 intake and plasma PLP.RESULTSThe mean dietary and total (dietary plus supplemental) vitamin B6 intake was 1.94 ± 0.64 and 2.41 ± 1.45 mg/day, respectively. Median (50th percentile) dietary intake of men and women was 2.062 and 1.706 mg/day. Foods from plant sources provided 70.61% of dietary vitamin B6 intake. Only 6.3% of subjects consumed total vitamin B6 less than Estimated Average Requirements. Plasma PLP concentration of all subjects was 40.03 ± 23.71 nmol/L. The concentration of users of vitamin B6 supplements was significantly higher than that of nonusers (P < 0.001). Approximately 16% of Korean adults had PLP levels < 20 nmol/L, indicating a biochemical deficiency of vitamin B6, while 19.7% had marginal vitamin B6 status. Plasma PLP concentration showed positive correlation with total vitamin B6 intake (r = 0.40984, P < 0.0001).CONCLUSIONSIn this study, vitamin B6 intake of Korean adults was generally adequate. However, one-third of subjects had vitamin B6 deficiency or marginal status. Therefore, in some adults in Korea, consumption of vitamin B6-rich food sources should be encouraged.

Urinary Methylmalonic Acid as an Indicator of Early Vitamin B12 Deficiency and Its Role in Polyneuropathy in Type 2 Diabetes

The rising incidence of diabetes and its negative impact on quality of life highlights the urgent need to develop biomarkers of early nerve damage. Measurement of total vitamin B12 has some limitations. We want to determine the levels of urinary methylmalonic acid and its relationships with serum vitamin B12 and polyneuropathy. The 176 Chinese patients with Type 2 diabetes mellitus were divided into 3 groups according to the levels of vitamin B12. A gas chromatography mass spectrometric technique was used to determine blood methylmalonic acid and urinary methylmalonic acid. The diagnosis of distal diabetic polyneuropathy was based on the determination of bilateral limb sensory and motor nerve conduction velocity and amplitude with electromyogram. Multiple regression analysis revealed that urinary methylmalonic acid/creatinine, blood methylmalonic acid, and so forth were variables that influenced diabetic polyneuropathy significantly. Nerve sensory conduction velocity and nerve amplitude in the group of urinary methylmalonic acid/creatinine >3.5 mmol/mol decreased significantly. Superficial peroneal nerve sensory and motor conduction velocity and ulnar nerve compound motor active potential amplitude were inversely correlated with urinary methylmalonic acid/creatinine. Urinary methylmalonic acid correlates with serum vitamin B12 levels in person with diabetes and is a sensitive marker of early polyneuropathy.

Differential responses of B vitamins in black soybean seeds

This study was aimed to determine the contents and the association of B vitamins from seeds of 10 black and one yellow soybean (Glycine max (L.) Merr.) varieties with either green or yellow cotyledon. Thiamine, flavin adenine dinucleotide (FAD), riboflavin and total riboflavin were found highest in ‘Chengjakong’, while flavin mononucleotide (FMN) was greatest in ‘Mirang’. Nicotinic acid and total vitamin B3 were highest in ‘Shingi’ as a yellow soybean variety but pantothenic acid and pyridoxine contents were greatest in ‘Tawon’ and ‘Mirang’, respectively. These content variations of B vitamins directly reflected the wide segregation of soybean varieties on the principal component analysis (PCA) scores plot, indicating that these 4 soybean varieties appeared to be least associated with other soybean varieties based on the different responses of B vitamins. The results of cluster and correlation analyses presented that the cotyledon colour of soybean seed contributed to a variation of B vitamin contents. Overall, the results suggest that a wide range of B vitamin contents would be affected by genotypic factors alongside the difference of cotyledon colour.

Interactions between plasma concentrations of folate and markers of vitamin B12status with cognitive performance in elderly people not exposed to folic acid fortification: the Hordaland Health Study

A combination of high folate with low vitamin B12 plasma status has been associated with cognitive impairment in a population exposed to mandatory folic acid fortification. The objective of the present study was to examine the interactions between plasma concentrations of folate and vitamin B12 markers in relation to cognitive performance in Norwegian elderly who were unexposed to mandatory or voluntary folic acid fortification. Cognitive performance was assessed by six cognitive tests in 2203 individuals aged 72-74 years. A combined score was calculated using principal component analysis. The associations of folate concentrations, vitamin B12 markers (total vitamin B12, holotranscobalamin (holoTC) and methylmalonic acid (MMA)) and their interactions in relation to cognitive performance were evaluated by quantile regression and least-squares regression, adjusted for sex, education, apo-ɛ4 genotype, history of CVD/hypertension and creatinine. Cross-sectional analyses revealed an interaction (P=0·009) between plasma concentrations of folate and vitamin B12 in relation to cognitive performance. Plasma vitamin B12 concentrations in the lowest quartile (<274pmol/l) combined with plasma folate concentrations in the highest quartile (>18·5nmol/l) were associated with a reduced risk of cognitive impairment compared with plasma concentrations in the middle quartiles of both vitamins (OR 0·22, 95% CI 0·05, 0·92). The interaction between folate and holoTC or MMA in relation to cognitive performance was not significant. In conclusion, this large study population unexposed to mandatory folic acid fortification showed that plasma folate, but not plasma vitamin B12, was associated with cognitive performance. Among the elderly participants with vitamin B12 concentrations in the lower range, the association between plasma folate and cognitive performance was strongest.

Oral manifestations and blood profile in patients with thalassemia trait

Patients with thalassemia trait (TT) may have anemia. This study evaluated whether TT patients had specific oral manifestations and a particular blood profile compared with normal individuals. The oral manifestations and mean red blood cell count, corpuscular cell volume, red blood cell distribution width, Mentzer index, and Green and King index as well as blood concentrations of hemoglobin, iron, total iron binding capacity, vitamin B12, folic acid, and homocysteine in 65 TT patients and in 130 age- and sex-matched healthy controls were measured and compared. TT patients had significantly higher frequencies of all oral manifestations than healthy controls (p < 0.001 for all), in which burning sensation of oral mucosa (90.8%), lingual varicosity (90.8%), dry mouth (72.3%), atrophic glossitis (32.3%), and numbness of the oral mucosa (30.8%) were the five leading oral manifestations for TT patients. Moreover, TT patients had significantly lower mean hemoglobin level, corpuscular cell volume, Mentzer index, and Green and King index (p < 0.001 for all) as well as significantly higher mean red blood cell count and red blood cell distribution width (p < 0.001 for both) than healthy controls. However, no significant difference in the mean blood iron, total iron binding capacity, vitamin B12, folic acid, or homocysteine levels was discovered between 65 TT patients and 130 healthy controls. TT patients have specific oral manifestations and a particular blood profile compared to normal individuals.

Determination of free and bound riboflavin in cow’s milk using a novel flavin-binding protein

A recently described putative protease from the gut bacterium Bacteroides thetaiotaomicron (termed ppBat) exhibits two tryptophan residues in the interface which enable specific binding of the isoalloxazine heterocycle of riboflavin and its two cofactor forms, FMN and FAD. Recombinant ppBat was used to capture riboflavin from bovine milk directly without any prior preparation steps. The flavin-loaded protein was then re-isolated by means of affinity chromatography to identify and quantify the captured flavins. Free riboflavin concentrations were determined to 197 and 151μg/l for milk with 3.5% and 0.5% fat content, respectively. Total riboflavin concentrations were also determined after acid-treatment of milk and were 4–5 times higher than for free riboflavin. Free FMN and FAD were not detectable and only trace amounts of FMN were found in milk following acid treatment. The method appears to be amenable to develop a direct assay for free riboflavin in milk and other foods.

Gebeliğin İlk Trimesterindeki Anemi Etyolojisinde Mikrobesin Eksikliğinin Önemi

Objective: To determine the frequency of anemia in pregnant women admitted to our hospital for the purpose of examination in the first trimester, to determine the location of micronutrient defi- ciencies in the etiology of anemia and to make analysis of demo- graphic factors associated with anemia. Methods: This study included 366 pregnant women below 12 weeks of gestation between November 2011 and February 2013. Pregnant women together with demographic data were examined in terms of hemoglobin, hematocrit, serum iron, total iron bind- ing capacity, ferritin, folate, vitamin B12 levels. Tests were statis- tically evaluated with demographic analysis. Results: The mean maternal hemoglobin, hematocrit, serum iron, total iron binding capacity, ferritin, folate, and vitamin B12 levels were respectively 12.6±1.02 g/dl, 36%±4.12, 76.63±44.76 μg/dl, 302.28±93.14 ng/dl, 19.35±20.43 ng/ml, 11.2±8.31 ng/ml and 187.2±101.14 pg/ml. The study evaluated 344 pregnant women and anemia was detected in 79 of them. In our study, the frequency of anemia was calculated to be 22.96%. Analyzing the etiology of anemic pregnant women, iron deficiency anemia was diagnosed in 35 patients (44.3%), vitamin B12 deficiency in 44 patients (55.7%), combination of vitamin B12 and iron deficiency was found in 9 patients. None of the patients were found to have folic acid deficiency. Conclusion: The frequency of anemia in pregnant women was found as 22.96%, which shows that the vitamin B12 deficiency is important in the etiology of anemia as frequent as iron deficiency.

Plasma Homocysteine Concentrations in the Acute Phase After Central Retinal Vein Occlusion in a Chinese Population

Purpose: To explore the relationship between total plasma homocysteine (tHcy) concentration and central retinal vein occlusion (CRVO) in the acute phase in a Chinese population.Methods: This was a matched case–control study, and participants were recruited between January 2008 and April 2012. The cohort included 68 consecutive patients with CRVO and 68 controls, matched for age and gender, aged 50 years and over. The total plasma homocysteine, vitamin B12 and folate levels and the presence of C677T MTHFR polymorphisms were analyzed in all patients and controls. Fasting venous blood samples were collected within three days after CRVO.Results: There were no significant differences (p = 0.134) in mean plasma tHcy between CRVO patients (10.73 ± 3.21 µmol/l) and controls (9.99 ± 2.57 µmol/l), nor were there any statistically significant differences when subjects were categorized by ischemic and nonischemic CRVO. However, six patients (27.3%) in the ischemic group and three patients (6.5%) in the nonischemic group were found to have hyperhomocysteinemia (p = 0.018). There were no statistically significant differences in serum folate (p = 0.503) or vitamin B12 levels (p = 0.419) between CRVO patients (folate, 5.97 ± 2.06 ng/ml; vitamin B12, 411 ± 122 pg/ml) and controls (folate, 6.18 ± 1.42 ng/ml; vitamin B12, 427 ± 115 pg/ml). The prevalence of the homozygous genotype of the MTHFR C677T mutation was not significantly different in patients than in controls.Conclusions: We found no association between tHcy in the acute phase after CRVO and CRVO occurrence in a Chinese population, but hyperhomocysteinemia were associated with the development of CRVO.

Antagonistic effect of myo-inositol on riboflavin production in two riboflavinogenic fungi Ashbya gossypii and Eremothecium ashbyi

Ashbya gossypii and Eremothecium ashbyi are riboflavin over producing fungi. Guanosine tri-phosphate (GTP) cyclohydrolase II, encoded by RIB1 gene, catalyses the rate limiting step of the riboflavin biosynthetic pathway. We report here the antagonistic effect of myo-inositol on riboflavin production in these two fungi by adapting them in Yeast Malt Agar (YMA) media containing 0.1% inositol. The adapted E. ashbyi showed 92% reduction and the adapted Ashbya showed 39% increase in the total riboflavin production, when compared to that produced by E. ashbyi and Ashbya respectively. Reverse transcription-polymerase chain reaction (RT-PCR) study indicated that myo-inositol reduced RIB1 gene expression in adapted E. ashbyi but enhanced the same in adapted Ashbya.

Response of vitamin B12 status to a controlled B12 intake in nonpregnant, pregnant, and lactating women

As part of a 12‐wk controlled feeding study, pregnant (n=26, 27 wk gestation), lactating (n=28, 5 wk postpartum), and nonpregnant (n=21) women consumed the study vitamin B12 dose of 7.5 μg/d [prenatal supplement (2.6 μg/d) and natural food (~4.9 μg/d)]. All participants achieved adequate vitamin B12 status throughout the study. Serum total vitamin B12 remained constant in pregnant and lactating women, whereas it increased in nonpregnant women (P=0.001). At study end, total B12 (mean ± SD) was lower in pregnant women (335 ± 104 pmol/L) than lactating (496 ± 127 pmol/L, P&lt;0.001) and nonpregnant (422 ± 82 pmol/L, P=0.015) women. The consumption of the study B12 dose increased both serum holotranscobalamin (holoTC) and the fraction of total serum vitamin B12 bound to TC (holoTC/B12 ratio) within physiologic groups (P ≤0.001 and P ≤0.037, respectively). At study end, pregnant women had higher holoTC/B12 ratio (31%) than nonpregnant women (22%, P=0.035) and lactating women (24%, P=0.056) suggesting that pregnancy increased the tissue availability of circulating B12. Overall, these data suggest that consumption of the study vitamin B12 dose (~ 2.5 times the RDA) met the vitamin B12 requirements of our study participants and maintained B12 concentrations in third trimester pregnant women by increasing holoTC concentrations. Funded in part by USDA, AEB‐ENC and the Beef Checkoff.

Vitamin B12 and homocysteine status during pregnancy in the metformin in gestational diabetes trial: responses to maternal metformin compared with insulin treatment

The aim of the study is to compare the effects of metformin and insulin treatment for gestational diabetes mellitus (GDM) on vitamin B12 and homocysteine (Hcy) status. Women with GDM, who met criteria for insulin treatment, were randomly assigned to metformin (n = 89) or insulin (n = 91) in the Adelaide cohort of the metformin in gestational diabetes (MiG) trial. Fasting serum total vitamin B12 (TB12), holotranscobalamin (HoloTC), a marker of functional B12 status and plasma Hcy concentrations were measured at 20-34 weeks (at randomization) and 36 weeks gestation, then at 6-8 weeks postpartum. Circulating TB12, HoloTC and Hcy were similar in both treatment groups at each time point. Women who were taking dietary folate supplements at randomization had higher serum TB12 and HoloTC at randomization than those not taking folate. Overall, serum TB12 fell more between randomization and 36 weeks gestation in the metformin group than in the insulin group (metformin: -19.7 ± 4.7 pmol/l, insulin: -6.4 ± 3.6 pmol/l, p = 0.004). The decrease in serum TB12 during treatment was greater with increasing treatment duration in metformin-treated (p < 0.001), but not in insulin-treated women. Total, but not bioavailable, vitamin B12 stores were depleted during pregnancy to a greater extent in metformin-treated than in insulin-treated women with GDM, but neither analyte differed between groups at any stage. This adds further evidence supporting metformin as a safe alternative treatment to insulin in GDM. Further investigation is needed to evaluate whether women treated with metformin for longer periods in pregnancy require additional B12 or other supplementation.

Preoperative Nutritional Deficiencies in Severely Obese Bariatric Candidates are not Linked to Gastric Helicobacter pylori Infection

Severely obese subjects have been found to show a high prevalence of distinct nutritional deficiencies even without any bariatric intervention but the underlying reasons remain obscure. We tested the hypothesis that gastric Helicobacter pylori infection is associated with increased nutritional deficiency rates. Taking advantage of our large database, we identified 404 patients who had undergone a gastroscopy--as a standard diagnostic assessment before bariatric surgery--along with a histological examination of gastric mucosal biopsies with concurrent nutritional blood measurements. Eighty-five (21 %) of the obese patients included in the study displayed a gastric H. pylori infection. Sex distribution, age and body mass index did not differ between H. pylori+ and H. pylori- patients (P > 0.29). Referring to nutritional markers, neither serum levels of total protein, albumin, calcium, phosphate, magnesium, ferritin, zinc, copper, vitamin B12, folate and 25-OH vitamin D3 nor respective deficiency rates differed between the H. pylori+ and H. pylori- patients group (all P > 0.13). Overall, 49.5 % of the bariatric candidates displayed at least one nutritional deficiency. Our data confirm previous reports on high prevalences of nutritional deficiencies in severely obese subjects. However, they do not provide evidence for a contributing role of gastric H. pylori infection to these nutritional alterations.

Contribution of meat to vitamin B12, iron and zinc intakes in five ethnic groups in the USA: implications for developing food‐based dietary guidelines

To describe the sources of meat and their contributions to vitamin B₁₂, iron and zinc in five ethnic groups in the USA. Dietary data for the Multiethnic Cohort, established in Hawaii and Los Angeles, were collected using a quantitative food frequency questionnaire from more than 215,000 subjects, aged 45-75 years at baseline (1993-1996). Participants included African American, Latino, Japanese American, Native Hawaiian and Caucasian men and women. Servings of meat items were calculated based on the US Department of Agriculture recommendations and their contributions to intakes of total meat, red meat, vitamin B₁₂, iron and zinc were determined. Of all types of meat, poultry contributed the most to meat consumption, followed by red meat and fish among all ethnicities, except for Latino (born in Mexico and Central/South America) men who consumed more beef. Lean beef was the most commonly consumed red meat for all ethnic-sex groups (9.3-14.3%), except for Native Hawaiian and Japanese American men, and Japanese American women whose top contributor was stew/curry with beef/lamb and stir-fried beef/pork with vegetables, respectively. The contribution of meat was most substantial for zinc (11.1-29.3%) and vitamin B₁₂ (19.7-40%) and, to a lesser extent, for iron (4.3-14.2%). This is the first large multiethnic cohort study to describe meat sources and their contributions to selected nutrients among ethnic minorities in the USA. These findings may be used to develop ethnic-specific recommendations for meat consumption aiming to improve dietary quality among these groups.

Utility and limitations of biochemical markers of vitamin B12 deficiency

There is an urgent need for proper utilization of laboratory markers to diagnose vitamin B12 deficiency that should reduce false negative cases. We worked out a diagnostic algorithm that provides a two-step detection of vitamin B12 deficiency using holotranscobalamin as a first line marker and methylmalonic acid (MMA) as a second line marker. We tested 1359 serum samples sent to our laboratory for total vitamin B12 assay. Serum samples were used for the determination of holotranscobalamin, MMA and creatinine. Compared with total B12, holotranscobalamin showed a higher area under the receiver operating characteristic curve for detecting MMA levels > 300 nM. However, the distribution of holotranscobalamin in individuals with elevated creatinine irrespective of MMA and in individuals with elevated MMA irrespective of creatinine was shifted into the higher ranges. In the grey zone of holotranscobalamin between 23 and 75 pM (the range extending from the 90% diagnostic sensitivity to the 90% diagnostic specificity), MMA testing as a second line marker would help detecting 18% of deficient cases. Lowering MMA after vitamin B12 treatment may help setting the diagnosis of B12 deficiency in individuals with elevated creatinine. Testing for vitamin B12 deficiency should start with holotranscobalamin measurement. Holotranscobalamin between 23 and 75 pM should be followed by MMA testing that can filter substantial number of deficient cases in the grey range in individuals with normal renal function. This diagnostic strategy may significantly improve assessing vitamin B12 deficiency.

The effects of nitrous oxide on vitamin B12 and homocysteine levels in methyltetrahydrofolate reductase gene mutation

We aimed to investigate the effects of nitrous oxide on plasma total homocysteine and vitamin B12 levels in patients with or without methyltetrahydrofolate reductase (MTHRF) gene mutation. After obtaining the ethics committee approval and written informed consents of patients, 93 patients between 18-70 years of age scheduled for surgery anticipated to last 1-4 hours were enrolled in the study. Patients with contraindications for nitrous oxide use were excluded. Preoperatively, blood samples were obtained from all patients for the determination of MTHFR gene mutation. Anesthesia induction was achieved with 3 mg.kg-1 of propofol and 1 µg.kg-1 of fentanyl. Anesthesia maintenance was performed with sevoflurane and with a carrier gas composed of 40 % O2 and 60 % N2O. Venous blood samples were obtained after venous canulation, and 24 hours after extubation for the analysis of plasma total homocysteine, vitamin B12 levels. Eighty-one patients were included in the study. Postoperative vitamin B12 levels were found to be significantly lower when compared with their preoperative levels (p<0.05). It was found that MTHRF gene polymorphism had no significant effect on postoperative plasma total homocysteine and serum vitamin B12 levels (p>0.05). Postoperative plasma total homocysteine levels were found to be significantly different between patients with operation times under and over 3 hours (p=0.028). We conclude that MTHRF gene polymorphism had no significant effects on postoperative plasma total homocysteine levels. However, we found that homocysteine levels might rise in patients who received general anesthesia with nitrous oxide for longer than 3 hours (Tab. 7, Ref. 26).

Epidemiological and investigative study of premature graying of hair in higher secondary and pre-university school children

Background:Hair pigmentation is one of the most conspicuous phenotypes in humans ranging from black, brown, and blonde to red. Premature graying of hair occurs more commonly without any underlying pathology but is said to be inherited in autosomal dominant pattern. Premature graying has been shown to be associated with a few of the autoimmune disorders. A role for environmental factors and nutritional deficiencies has also been postulated. However, to date the exact etiology of premature graying has not been established.Aim:The objective of our study was to conduct an epidemiological and investigative study of premature graying of hair in higher secondary and pre-university school children of the semi-urban area.Materials and Methods:A total of 35 cases and controls were investigated for various parameter such as Hemoglobin, total iron binding capacity, serum ferritin (S. Ferritin), serum calcium (S. Ca), serum iron (S. Iron), vitamin B12, and vitamin D3 after taking informed consent. Epidemiological and investigations correlation was established using the Chi-square and Mann Whitney test and P < 0.05 values were considered significant.Result:Among the various laboratory parameters S. Ca, S. Ferritin and vitamin D3 were low in patients with premature graying of hair. There was significant high number of vitamin D3 deficient and insufficient among the cases compared to the controls.Conclusion:According to our study S. Ca, S. Ferritin, vitamin D3 may play a role in premature graying of hair in our society.

Prevalence of Restless Legs Syndrome in Patients Treated with Peritoneal Dialysis: Clinical and Biochemical Characteristics among Patients with and without Restless Legs Syndrome

Introduction and Aims:This is a prospective study identifying prevalence of Restless Legs Syndrome (RLS) in patients ongoing peritoneal dialysis (PD) due to end stage renal disease (ESRD) and comparing clinical and biochemical characteristics among patients with and without RLS. Methods: Two hundred ESRD patients who received PD at least six months assessed by neurologist and nephrologist with regards to presence of RLS. Also, clinical and biochemical features of these patients are determined. One hundred and forty four patients were excluded from study because they had other secondary causes of RLS except for ESRD. Results: Thirteen of 56 patients (23.2%) had RLS. The use of vitamin B + folic acid supplements was significantly lower in patients with RLS than in those without RLS (69.2% vs 97.7%; p = 0.008). There was no significant difference between patient groups with and without RLS in terms of age, gender, body mass index, cause of ESRD, peritoneal membrane transport characteristic, smoking, consuming alcohol, use of erythropoietin, duration of PD, hemoglobin, serum calcium, serum phosphorus, serum albumin, levels of serum iron, total iron binding capacity, ferritin, folic acid and vitamin B12, transferrin saturation, weekly Kt/V urea value, and amount of residual urine volume (p > 0.05). Conclusion: RLS is more common among PD patients than general population. Although essential cause is not exactly known, use of folic acid and vitamin B complex decrease the RLS prevalence in this particular patient group.

Serum vitamin B12 not reflecting vitamin B12 status in patients with type 2 diabetes

Contradictory results for concentrations of vitamin B12, holotranscobalamin (holoTC), and methylmalonic acid (MMA) have been reported. We tested the hypothesis that the extracellular vitamin B12 markers are not reflecting the intracellular vitamin B12-dependent biochemical reactions in individuals with type 2 diabetes. The study included 92 patients with diabetes and 72 controls with similar age and sex distribution. We measured vitamin B12 markers [MMA, total serum vitamin B12, holoTC, total homocysteine (tHcy)], red blood cell (RBC)-B12, and the plasma concentrations of the methylation markers [S-adenosylmethionine (SAM) and S-adenosylhomocysteine (SAH)]. In comparison to controls, diabetic patients showed significantly higher concentrations of plasma SAH (median 15.1 vs. 11.8nmol/L; p<0.001) and lower SAM/SAH ratio (9.1 vs. 8.2; p=0.006). Concentrations of total vitamin B12 andholoTC did not differ significantly between the groups, but plasma MMA concentrations were significantly higher in diabetics (250 vs. 206nmol/L). However, RBC-B12 was lower in diabetics compared tocontrols (median 230 vs. 260pmol/L; p=0.001). The inverse correlation between MMA and RBC-B12 was stronger in the controls compared to that in the patients (correlation coefficient in controls R=-0.446, p=0.001; in patients R=-0.289, p=0.022). Metformin treatment was associated with a lower total serum vitamin B12, but a comparable RBC-B12 and a slightly lower MMA and better methylation index. In conclusion, patients with type 2 diabetes showed normal extracellular vitamin B12, but disturbed intracellular B12-dependent biochemical reactions. Metformin treatment was associated with low serum vitamin B12 and improved intracellular vitamin B12 metabolism despite low serum vitamin B12.