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Sample records for b12 absorption based

  1. Assessment of vitamin B(12) absorption based on the accumulation of orally administered cyanocobalamin on transcobalamin.

    Science.gov (United States)

    Hardlei, Tore Forsingdal; Mørkbak, Anne Louise; Bor, Mustafa Vakur; Bailey, Lynn B; Hvas, Anne-Mette; Nexo, Ebba

    2010-03-01

    Vitamin B(12), or cobalamin (Cbl), is absorbed in the intestine and transported to the cells bound to transcobalamin (TC). We hypothesize that cyanocobalamin (CNCbl) is absorbed unchanged, thereby allowing measurement of the complex of CNCbl bound to TC (TC-CNCbl) to be used for studying the absorption of the vitamin. TC was immunoprecipitated from serum samples obtained from healthy donors at baseline and at 24 h after oral administration of three 9-microg CNCbl doses over 1 day. Cbl was released by treatment with subtilisin Carlsberg. The different forms of Cbl were isolated by HPLC and subsequently quantified with an ELISA-based Cbl assay. At baseline, the median TC-CNCbl concentration was 1 pmol/L (range, 0-10 pmol/L); the intraindividual variation (SD) was 1.6 pmol/L (n = 31). After CNCbl administration, the TC-CNCbl concentration increased significantly (P = 0.0003, paired t-test), whereas no major changes were observed in any of the other Cbl forms bound to TC (n = 10). Only a moderate additional increase in TC-CNCbl was observed with prolonged (5 days) CNCbl administration (n = 10). We designed an absorption test based on measuring TC-CNCbl at baseline and 24 h after CNCbl intake and established a reference interval for the increase in TC-CNCbl (n = 78). The median absolute increase was 23 pmol/L (range, 6-64 pmol/L), and the relative increase was >3-fold. Our data demonstrate that CNCbl is absorbed unchanged and accumulates on circulating TC. We suggest that measuring TC-CNCbl will improve the assessment of vitamin B(12) absorption.

  2. Vitamin B12 absorption capacity in healthy children

    Energy Technology Data Exchange (ETDEWEB)

    Hjelt, K.; Krasilnikoff, P.A.

    1986-03-01

    B12 absorption was investigated in 47 healthy children aged 7 months to 15.8 years (median 4.9 years). The patients had either recovered from giardiasis, the post-gastroenteritis syndrome, or had celiac disease in remission (treated with a gluten-free diet). The B12 absorption was measured by a double-isotope technique using /sup 57/CoB12 and /sup 51/CrCl/sub 3/, the latter being the inabsorbable marker. The radiation dose was minimal. The results were presented as fractional absorption of B12 (FAB12). Within the different age groups, the absorption test was performed by means of the following oral amounts of B12: 0- less than 1 year, 0.5 microgram; 1-3 years: 1.7 micrograms, 4-6 years, 2.5 micrograms; 7-10 years; 3.3 micrograms; and 11-15 years, 4.5 micrograms. When using these oral amounts of B12, the medians (and ranges) of FAB12 were found to be: 1-3 years (n = 18), 37% (16-80%); 4-6 years (n = 10), 27% (19-40%); 7-10 years (n = 9), 32% (21-44%); and 11-15 years (n = 8), 27% (19-59%). The FAB12 in two children aged 7 and 11 months was 31% and 32%, respectively. These results may be interpretated as reference values for B12 absorption in children. Further absorption tests were performed in seven children representing the four age groups from 1 to 15 years. When a high oral amount of B12 was given (i.e., three times the saturation dose), the FAB12 ranged from 0 to 20% (median 9%), whereas a low amount (i.e., one-ninth of the saturation dose) produced fractional absorptions from 65 to 82% (median 74%).

  3. Assay for vitamin B12 absorption and method of making labeled vitamin B12

    Science.gov (United States)

    Anderson, Peter J [Davis, CA; Dueker, Stephen [Davis, CA; Miller, Joshua [Davis, CA; Green, Ralph [Elmacero, CA; Roth, John [Davis, CA; Carkeet, Colleen [Silver Spring, MD; Buchholz,; Bruce, A [Orinda, CA

    2012-06-19

    The invention provides methods for labeling vitamin B12 with .sup.14C, .sup.13C, tritium, and deuterium. When radioisotopes are used, the invention provides for methods of labeling B12 with high specific activity. The invention also provides labeled vitamin B12 compositions made in accordance with the invention.

  4. Holo-transcobalamin is an indicator of vitamin B-12 absorption in healthy adults with adequate vitamin B-12 status

    DEFF Research Database (Denmark)

    von Castel-Roberts, Kristina M; Mørkbak, Anne Louise; Nexo, Ebba

    2007-01-01

    BACKGROUND: It has been hypothesized that the response of holo-transcobalamin (holo-TC) to oral vitamin B-12 may be used to assess absorption. To develop a reliable clinical absorption test that uses holo-TC, it is necessary to determine the optimal timeline for vitamin B-12 administration...... and postdose assessment. OBJECTIVE: The objective of this study was to assess the magnitude and patterns of change in the postabsorption response of holo-TC to oral vitamin B-12. DESIGN: Adult (18-49 y) male and female participants (n = 21) with normal vitamin B-12 status were given three 9-mug doses...... of vitamin B-12 at 6-h intervals beginning early morning (baseline) on day 1. Blood was drawn at 17 timed intervals over the course of 3 d for the analysis of holo-TC and other indicators of vitamin B-12 status. RESULTS: Mean holo-TC increased significantly (P

  5. Increases in plasma holotranscobalamin can be used to assess vitamin B-12 absorption in individuals with low plasma vitamin B-12.

    Science.gov (United States)

    Bhat, Dattatray S; Thuse, Nileema V; Lubree, Himangi G; Joglekar, Charudatta V; Naik, Sadanand S; Ramdas, Lalita V; Johnston, Carole; Refsum, Helga; Fall, Caroline H; Yajnik, Chittaranjan S

    2009-11-01

    Low plasma concentrations of vitamin B-12 are common in Indians, possibly due to low dietary intakes of animal-source foods. Whether malabsorption of the vitamin contributes to this has not been investigated. A rise in the plasma holotranscobalamin (holo-TC) concentration after a standard dose of oral vitamin B-12 has been proposed as a measure of gastrointestinal absorption in people with normal plasma vitamin B-12 concentrations. We studied 313 individuals (children and parents, 109 families) in the Pune Maternal Nutrition Study. They received 3 doses of 10 microg (n = 191) or 2 microg (n = 122) of cyanocobalamin at 6-h intervals. A rise in plasma holo-TC of > or =15% and >15 pmol/L above baseline was considered normal vitamin B-12 absorption. The baseline plasma vitamin B-12 concentration was 10 micromol/L in children and >15 micromol/L in adults). In the 10 microg group, the plasma holo-TC concentration increased by 4.8-fold from (mean +/- SD) 9.3 +/- 7.0 pmol/L to 53.8 +/- 25.9 pmol/L and in the 2 microg group by 2.2-fold from 11.1 +/- 8.5 pmol/L to 35.7 +/- 19.3 pmol/L. Only 10% of the participants, mostly fathers, had an increase less than the suggested cut-points. Our results suggest that an increase in plasma holo-TC may be used to assess vitamin B-12 absorption in individuals with low vitamin B-12 status. Because malabsorption is unlikely to be a major reason for the low plasma vitamin B-12 concentrations in this population, increasing dietary vitamin B-12 should improve their status.

  6. Theoretical analysis of electronic absorption spectra of vitamin B12 models

    Science.gov (United States)

    Andruniow, Tadeusz; Kozlowski, Pawel M.; Zgierski, Marek Z.

    2001-10-01

    Time-dependent density-functional theory (TD-DFT) is applied to analyze the electronic absorption spectra of vitamin B12. To accomplish this two model systems were considered: CN-[CoIII-corrin]-CN (dicyanocobinamide, DCC) and imidazole-[CoIII-corrin]-CN (cyanocobalamin, ImCC). For both models 30 lowest excited states were calculated together with transition dipole moments. When the results of TD-DFT calculations were directly compared with experiment it was found that the theoretical values systematically overestimate experimental data by approximately 0.5 eV. The uniform adjustment of the calculated transition energies allowed detailed analysis of electronic absorption spectra of vitamin B12 models. All absorption bands in spectral range 2.0-5.0 eV were readily assigned. In particular, TD-DFT calculations were able to explain the origin of the shift of the lowest absorption band caused by replacement of the-CN axial ligand by imidazole.

  7. Vitamin B12 deficiency.

    Science.gov (United States)

    Oh, Robert; Brown, David L

    2003-03-01

    Vitamin B12 (cobalamin) deficiency is a common cause of macrocytic anemia and has been implicated in a spectrum of neuropsychiatric disorders. The role of B12 deficiency in hyperhomocysteinemia and the promotion of atherosclerosis is only now being explored. Diagnosis of vitamin B12 deficiency is typically based on measurement of serum vitamin B12 levels; however, about 50 percent of patients with subclinical disease have normal B12 levels. A more sensitive method of screening for vitamin B12 deficiency is measurement of serum methylmalonic acid and homocysteine levels, which are increased early in vitamin B12 deficiency. Use of the Schilling test for detection of pernicious anemia has been supplanted for the most part by serologic testing for parietal cell and intrinsic factor antibodies. Contrary to prevailing medical practice, studies show that supplementation with oral vitamin B12 is a safe and effective treatment for the B12 deficiency state. Even when intrinsic factor is not present to aid in the absorption of vitamin B12 (pernicious anemia) or in other diseases that affect the usual absorption sites in the terminal ileum, oral therapy remains effective.

  8. Human vitamin B12 absorption measurement by accelerator mass spectrometry using specifically labeled (14)C-cobalamin.

    Science.gov (United States)

    Carkeet, Colleen; Dueker, Stephen R; Lango, Jozsef; Buchholz, Bruce A; Miller, Joshua W; Green, Ralph; Hammock, Bruce D; Roth, John R; Anderson, Peter J

    2006-04-11

    There is a need for an improved test of human ability to assimilate dietary vitamin B(12). Assaying and understanding absorption and uptake of B(12) is important because defects can lead to hematological and neurological complications. Accelerator mass spectrometry is uniquely suited for assessing absorption and kinetics of carbon-14 ((14)C)-labeled substances after oral ingestion because it is more sensitive than decay counting and can measure levels of (14)C in microliter volumes of biological samples with negligible exposure of subjects to radioactivity. The test we describe employs amounts of B(12) in the range of normal dietary intake. The B(12) used was quantitatively labeled with (14)C at one particular atom of the dimethylbenzimidazole (DMB) moiety by exploiting idiosyncrasies of Salmonella metabolism. To grow aerobically on ethanolamine, Salmonella enterica must be provided with either preformed B(12) or two of its precursors, cobinamide and DMB. When provided with (14)C-DMB specifically labeled in the C2 position, cells produced (14)C-B(12) of high specific activity (2.1 GBq/mmol, 58 mCi/mmol) (1 Ci = 37 GBq) and no detectable dilution of label from endogenous DMB synthesis. In a human kinetic study, a physiological dose (1.5 microg, 2.2 kBq/59 nCi) of purified (14)C-B(12) was administered and showed plasma appearance and clearance curves consistent with the predicted behavior of the pure vitamin. This method opens new avenues for study of B(12) assimilation.

  9. Vitamin B12 and cognitive function: an evidence-based analysis.

    Science.gov (United States)

    2013-01-01

    More than 2.9 million serum vitamin B12 tests were performed in 2010 in Ontario at a cost of $40 million. Vitamin B12 deficiency has been associated with a few neurocognitive disorders. To determine the clinical utility of B12 testing in patients with suspected dementia or cognitive decline. Three questions were addressed: Is there an association between vitamin B12 deficiency and the onset of dementia or cognitive decline? Does treatment with vitamin B12 supplementation improve cognitive function in patients with dementia or cognitive decline and vitamin B12 deficiency? What is the effectiveness of oral versus parenteral vitamin B12 supplementation in those with confirmed vitamin B12 deficiency? A literature search was performed using MEDLINE, Embase, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the Centre for Reviews and Dissemination database, from January 2002 until August 2012. Eighteen studies (7 systematic reviews and 11 observational studies) were identified to address the question of the association between B12 and the onset of dementia. Four systematic reviews were identified to address the question of the treatment of B12 on cognitive function. Finally, 3 randomized controlled trials were identified that compared oral B12 to intramuscular B12. Based on very low quality evidence, there does appear to be an association between elevated plasma homocysteine levels (a by-product of B vitamins) and the onset of dementia. Based on moderate quality evidence, but with less than optimal duration of follow-up, treatment with B12 supplementation does not appreciably change cognitive function. Based on low to moderate quality of evidence, treatment with vitamin B12 and folate in patients with mild cognitive impairment seems to slow the rate of brain atrophy. Based on moderate quality evidence, oral vitamin B12 is as effective as parenteral vitamin B12 in patients with confirmed B12 deficiency. Low levels of vitamin

  10. Low-dimensional boron structures based on icosahedron B12

    Science.gov (United States)

    Kah, C. B.; Yu, M.; Tandy, P.; Jayanthi, C. S.; Wu, S. Y.

    2015-10-01

    One-dimensional icosahedral boron chains and two-dimensional icosahedral boron sheets (icosahedral α, δ6, and δ4 sheets) that contain icosahedra B12 as their building units have been predicted in a computer simulation study using a state-of-the-art semi-empirical Hamiltonian. These novel low-dimensional icosahedral structures exhibit interesting bonding and electronic properties. Specifically, the three-center, two-electron bonding between icosahedra B12 of the boron bulk (rhombohedral boron) transforms into a two-center bonding in these new allotropes of boron sheets. In contrast to the previously reported stable buckled α and triangular boron monolayer sheets, these new allotropes of boron sheets form a planar network. Calculations of electronic density of states (DOS) reveal a semiconducting nature for both the icosahedral chain and the icosahedral δ6 and δ4 sheets, as well as a nearly gapless (or metallic-like) feature in the DOS for the icosahedral α sheet. The results for the energy barrier per atom between the icosahedral δ6 and α sheets (0.17 eV), the icosahedral δ6 and δ4 sheets (0.38 eV), and the icosahedral α and δ4 sheets (0.27 eV), as indicated in the respective parentheses, suggest that these new allotropes of boron sheets are relatively stable.

  11. Increases in Plasma Holotranscobalamin Can Be Used to Assess Vitamin B-12 Absorption in Individuals with Low Plasma Vitamin B-12123

    Science.gov (United States)

    Bhat, Dattatray S.; Thuse, Nileema V.; Lubree, Himangi G.; Joglekar, Charudatta V.; Naik, Sadanand S.; Ramdas, Lalita V.; Johnston, Carole; Refsum, Helga; Fall, Caroline H.; Yajnik, Chittaranjan S.

    2012-01-01

    Low plasma concentrations of vitamin B-12 are common in Indians, possibly due to low dietary intakes of animal-source foods. Weather malabosrption of the vitamin contributes to this has not been investigated. A rise in plasma holotranscobalamin (holo-TC) concentration after a standard dose of oral vitamin B-12 has been proposed as a measure of gastrointestinal absorption in people with normal plasma vitamin B-12 concentrations. We studied 313 individuals (children and parents, 109 families) in the Pune Maternal Nutrition Study. They received 3 doses of 10 μg (n=191) or 2 μg (n=122) of cyanocobalamin at 6 h intervals. A rise in plasma holo-TC of ≥15% and >15 pmol/L above baseline was considered normal vitamin B-12 absorption. The baseline plasma vitamin B-12 was 10 μmol/L in children and >15 μmol/L in adults). In 10 μg group plasma holo-TC concentration increased by 4.8 -fold from (mean ± SD) 9.3 ± 7.0 pmol/L to 53.8 ± 25.9 pmol/L, and in 2 μg group by 2.2 -fold from 11.1 ± 8.5 pmol/L to 35.7 ± 19.3 pmol/L. Only 10% of participants, mostly fathers, had an increase less than the suggested cut-points. Our results suggest that an increase in plasma holo-TC may be used to assess vitamin B-12 absorption in individuals with low vitamin B-12 status. Because malabsorption is unlikely to be a major reason for the low plasma vitamin B-12 concentrations in this population, increasing dietary vitamin B-12 should improve their status. PMID:19776185

  12. Lack of megalin expression in adult human terminal ileum suggests megalin‐independent cubilin/amnionless activity during vitamin B12 absorption

    OpenAIRE

    Jensen, Louise L.; Andersen, Rikke K.; Hager, Henrik; Madsen, Mette

    2014-01-01

    Abstract Cubilin plays an essential role in terminal ileum and renal proximal tubules during absorption of vitamin B12 and ligands from the glomerular ultrafiltrate. Cubilin is coexpressed with amnionless, and cubilin and amnionless are mutually dependent on each other for correct processing to the plasma membrane upon synthesis. Patients with defects in either protein suffer from vitamin B12‐malabsorption and in some cases proteinuria. Cubilin lacks a transmembrane region and signals for end...

  13. Elevated plasma vitamin B12 levels and cancer prognosis: A population-based cohort study

    DEFF Research Database (Denmark)

    Arendt, Johan Frederik Håkonsen; Farkas, Dora Kormendine; Pedersen, Lars;

    2015-01-01

    BACKGROUND: Elevated plasma vitamin B12 levels (cobalamin, Cbl) are associated with increased short-term cancer risk among patients referred for this laboratory measurement. We aimed to assess prognosis in cancer patients with elevated plasma Cbl. METHODS: We conducted a population-based cohort...

  14. Lack of megalin expression in adult human terminal ileum suggests megalin‐independent cubilin/amnionless activity during vitamin B12 absorption

    Science.gov (United States)

    Jensen, Louise L.; Andersen, Rikke K.; Hager, Henrik; Madsen, Mette

    2014-01-01

    Abstract Cubilin plays an essential role in terminal ileum and renal proximal tubules during absorption of vitamin B12 and ligands from the glomerular ultrafiltrate. Cubilin is coexpressed with amnionless, and cubilin and amnionless are mutually dependent on each other for correct processing to the plasma membrane upon synthesis. Patients with defects in either protein suffer from vitamin B12‐malabsorption and in some cases proteinuria. Cubilin lacks a transmembrane region and signals for endocytosis and is dependent on a transmembrane coreceptor during internalization. Amnionless has been shown to be able to mediate internalization of cubilin in a cell‐based model system. Cubilin has additionally been suggested to function together with megalin, and a recent study of megalin‐deficient patients indicates that uptake of cubilin ligands in the kidney is critically dependent on megalin. To further investigate the potential role of amnionless and megalin in relation to cubilin function in terminal ileum and vitamin B12 uptake, we initiated a study of CUBN/cubilin, AMN/amnionless, and LRP2/megalin expression in adult human terminal ileum. Our study is the first to reveal the expression pattern of cubilin, amnionless, and megalin in adult human terminal ileum, where cubilin and amnionless localize to the epithelial cells. Surprisingly, we did not detect any megalin protein in adult terminal ileum and consistently, only extremely low amounts of LRP2 mRNA. Our data therefore advocate that cubilin and amnionless act independently of megalin in adult terminal ileum and that the cubilin‐megalin interdependency accordingly should be considered as tissue and ligand specific. PMID:25052491

  15. Lack of megalin expression in adult human terminal ileum suggests megalin-independent cubilin/amnionless activity during vitamin B12 absorption.

    Science.gov (United States)

    Jensen, Louise L; Andersen, Rikke K; Hager, Henrik; Madsen, Mette

    2014-07-01

    Cubilin plays an essential role in terminal ileum and renal proximal tubules during absorption of vitamin B12 and ligands from the glomerular ultrafiltrate. Cubilin is coexpressed with amnionless, and cubilin and amnionless are mutually dependent on each other for correct processing to the plasma membrane upon synthesis. Patients with defects in either protein suffer from vitamin B12-malabsorption and in some cases proteinuria. Cubilin lacks a transmembrane region and signals for endocytosis and is dependent on a transmembrane coreceptor during internalization. Amnionless has been shown to be able to mediate internalization of cubilin in a cell-based model system. Cubilin has additionally been suggested to function together with megalin, and a recent study of megalin-deficient patients indicates that uptake of cubilin ligands in the kidney is critically dependent on megalin. To further investigate the potential role of amnionless and megalin in relation to cubilin function in terminal ileum and vitamin B12 uptake, we initiated a study of CUBN/cubilin, AMN/amnionless, and LRP2/megalin expression in adult human terminal ileum. Our study is the first to reveal the expression pattern of cubilin, amnionless, and megalin in adult human terminal ileum, where cubilin and amnionless localize to the epithelial cells. Surprisingly, we did not detect any megalin protein in adult terminal ileum and consistently, only extremely low amounts of LRP2 mRNA. Our data therefore advocate that cubilin and amnionless act independently of megalin in adult terminal ileum and that the cubilin-megalin interdependency accordingly should be considered as tissue and ligand specific.

  16. Indirect determination of vitamin B12 powder by flame atomic absorption spectrometry%间接火焰原子吸收光谱法测定维生素B12粉含量

    Institute of Scientific and Technical Information of China (English)

    吴剑平; 商军

    2007-01-01

    用火焰原子吸收光谱法间接测定饲料添加剂维生素B12粉中维生素B12的含量.该方法通过测定样品中的钴离子浓度计算维生素B12的含量.经试验,该方法在0.20~2.00 μg/mL线性关系良好,r=0.9992;有机栽体和无机载体中的维生素B12平均回收率分别为99.21%和98.98%,方法的检出限为0.061 μg/mL.本法操作简便易行,适用于饲料添加剂维生素B12粉中维生素B12含量测定.

  17. Human Vitamin B12 Absorption and Metabolism are Measured by Accelerator Mass Spectrometry Using Specifically Labeled 14C-Cobalamin

    Energy Technology Data Exchange (ETDEWEB)

    Carkeet, C; Dueker, S R; Lango, J; Buchholz, B A; Miller, J W; Green, R; Hammock, B D; Roth, J R; Anderson, P J

    2006-01-26

    There is need for an improved test of human ability to assimilate dietary vitamin B{sub 12}. Assaying and understanding absorption and uptake of B{sub 12} is important because defects can lead to hematological and neurological complications. Accelerator mass spectrometry (AMS) is uniquely suited for assessing absorption and kinetics of {sup 14}C-labeled substances after oral ingestion because it is more sensitive than decay counting and can measure levels of carbon-14 ({sup 14}C) in microliter volumes of biological samples, with negligible exposure of subjects to radioactivity. The test we describe employs amounts of B{sub 12} in the range of normal dietary intake. The B{sub 12} used was quantitatively labeled with {sup 14}C at one particular atom of the DMB moiety by exploiting idiosyncrasies of Salmonellametabolism. In order to grow aerobically on ethanolamine, S. entericamust be provided with either pre-formed B{sub 12} or two of its precursors: cobinamide and dimethylbenzimidazole (DMB). When provided with {sup 14}C-DMB specifically labeled in the C2 position, cells produced {sup 14}C-B{sub 12} of high specific activity (2.1 GBq/mmol, 58 mCi/mmol) and no detectable dilution of label from endogenous DMB synthesis. In a human kinetic study, a physiological dose (1.5 mg, 2.2 KBq/59 nCi) of purified {sup 14}C-B{sub 12} was administered and showed plasma appearance and clearance curves consistent with the predicted behavior of the pure vitamin. This method opens new avenues for study of B{sub 12} assimilation.

  18. Fasting time and vitamin B12 levels in a community-based population.

    Science.gov (United States)

    Orton, Dennis J; Naugler, Christopher; Sadrzadeh, S M Hossein

    2016-07-01

    Vitamin B12, also known as cobalamin (Cbl), is an essential vitamin that manifests with numerous severe but non-specific symptoms in cases of deficiency. Assessing Cbl status often requires fasting, although this requirement is not standard between institutions. This study evaluated the impact of fasting on Cbl levels in a large community-based cohort in an effort to promote standardization of Cbl testing between sites. Laboratory data for Cbl, fasting time, patient age and sex were obtained from laboratory information service from Calgary Laboratory Services (CLS) for the period of April 2011 to June 2015. CLS is the sole supplier of laboratory services in the Southern Alberta region in Canada (population, approximately 1.4 million). To investigate potential sex-specific effects of fasting on Cbl levels, males and females were analyzed separately using linear regression models. A total of 346,957 individual patient results (196,849 females, 146,085 males) were obtained. The mean plasma Cbl level was 386.5 (±195.6) pmol/L and 412.0 (±220.8) pmol/L for males and females, respectively. Linear regression analysis showed fasting had no significant association with Cbl levels in females; however a statistically significant decrease of 0.9pmol/L/hour fasting (pfasting has the potential to contribute to higher rates of Cbl deficiency in men. Together, these data suggest fasting should be excluded as a requirement for evaluating plasma Cbl. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Vitamin B-12

    Science.gov (United States)

    ... in vitamin B12 if I’m vegetarian or vegan?ResourcesNational Institutes of Health: MedlinePlus, Vitamin B12 Last Updated: March 2017 This article was contributed by: familydoctor.org editorial staff Tags: B12, B12 deficiency, diet, nutrition, vitamin B12, vitamins Food and Nutrition, Nutrients ...

  20. A molecular dynamics study on the structural and electronic properties of two-dimensional icosahedral B12 cluster based structures

    Science.gov (United States)

    Kah, Cherno Baba; Yu, M.; Jayanthi, C. S.; Wu, S. Y.

    2014-03-01

    Our previous study on one-dimensional icosahedral B12 cluster (α-B12) based chain [Bulletin of APS Annual Meeting, p265 (2013)] and ring structures has prompted us to study the two-dimensional (2D) α-B12 based structures. Recently, we have carried out a systematic molecular dynamics study on the structural stabilities and electronic properties of the 2D α-B12 based structures using the SCED-LCAO method [PRB 74, 15540 (2006)]. We have considered several types of symmetry for these 2D structures such as δ3, δ4, δ6 (flat triangular), and α' types. We have found that the optimized structures are energetically in the order of δ6 < α' < δ3 < δ4 which is different from the energy order of α'< δ6 < δ4 < δ3 found in the 2D boron monolayer sheets [ACS Nano 6, 7443 (2012)]. A detailed discussion of this study will be presented. The first author acknowledges the McSweeny Fellowship for supporting his research in this work.

  1. Vitamin B12

    Science.gov (United States)

    ... Consumer Datos en español Health Professional Other Resources Vitamin B12 Fact Sheet for Consumers Have a question? ... out more about vitamin B12? Disclaimer What is vitamin B12 and what does it do? Vitamin B12 ...

  2. EVIDENCE-BASED DATA ON EFFECTIVENESS OF LACTOBACILLUS RHAMNOSUS GG AND BIFIDOBACTERIUM LACTIS ВB-12 IN PEDIATRIC PRACTICE

    Directory of Open Access Journals (Sweden)

    I. V. Andreyeva

    2011-01-01

    Full Text Available Prophylactic and therapeutic administration of prebiotics in treatment of different disorders is used very often nowadays. However, this kind of a treatment confirmed its efficacy in only several diseases. The review presents the data on efficacy of two probiotic microorganisms (L. rhamnosus GG and B. lactis Вb-12 in pediatric practice. Author summarizes and analyzes existing evidence-based data on efficacy of probiotics in treatment of acute diarrhea, prophylaxis of antibiotic-associated diarrhea and nosocomial infections. L. rhamnosus GG and B. lactis Вb-12 have their own place in prophylaxis of infections of airways and gastrointestinal tract. Administration of probiotics for treatment and prophylaxis of allergic and other diseases is reviewed. Safety of probiotics is described as well.

  3. Ultrafast transient absorption studies of environment influence on the photolysis of B12 complexes and the subsequent recombination and escape of caged radicals

    Science.gov (United States)

    Stickrath, Andrew B.

    Femtosecond to nanosecond transient absorption experiments were performed on a series of B12 complexes to assess the influence of the solvent environment on the excited state electronic structure and resulting dynamics. A series of alkylcobalamins (adenosyl-, ethyl, methyl, and propylcobalamin), all of which are known to undergo cobalt-carbon bond homolysis in response to excitation at 400nm were studied in a variety of surroundings. Measurements on adenosylcobalamin (coenzyme B12) bound to glutamate mutase demonstrate a metal-to-ligand-charge-transfer (MLCT) state en route to bond homolysis, supported by protein influence on the excited state electronic structure. This charge transfer intermediate, which is similar to that reported in the literature for methylcobalamin, is not observed for free adenosylcobalamin. Measurements on methylcobalamin probe solvent influence on the MLCT state and characterize it by a large charge density transfer. This result is in contrast to studies on cyanocobalamin, which is not observed to undergo homolysis, where the solvent dependent lifetime of an intermediate ligand-to-metal-charge-transfer (LMCT) state is characterized by a modest transfer of charge density. Such a LMCT intermediate is observed for adenosylcobalamin in water leading to bond homolysis. The protein has greatly altered the photochemical pathway to homolysis, which is expected to be representative of influence on thermolysis. Upon homolysis the photoinduced alkyl and cob(II)alamin radicals may recombine or escape the solvent cage to form solvent separated radical pairs which do not recombine in the bulk by the 9ns time limit of these experiments. Recombination can be monitored directly via the oxidation state of the cobalt atom. The neutral alkyl radical is a paradigm for small particle escape and diffusive motion in a liquid. The escape behavior is similar for adenosyl, ethyl, and propyl radicals indicating that hydrogen bonding with the solvent is not a major

  4. Vitamin B12 deficiency

    Science.gov (United States)

    Vitamin B12 (B12; also known as cobalamin) is a B vitamin that has an important role in cellular metabolism, especially in DNA synthesis, methylation and mitochondrial metabolism. Clinical B12 deficiency with classic haematological and neurological manifestations is relatively uncommon. However, sub...

  5. Elevated plasma vitamin B12 levels and risk of venous thromboembolism among cancer patients: A population-based cohort study

    DEFF Research Database (Denmark)

    Arendt, Johan Frederik Håkonsen; Farkas, Dora Kormendine; Pedersen, Lars

    2017-01-01

    Introduction: Both venous thromboembolism (VTE) and high plasma vitamin B12 levels (cobalamin, Cbl) are markers of occult cancer and aggressive cancer with a poor prognosis. In this population-based cohort study, we assessed VTE risk among cancer patients with high plasma Cbl levels. Materials...... and categorised as either cancer-associated if no other provoking factors were present before VTE or provoked by other risk factors (surgery, trauma, or pregnancy). We calculated cumulative incidence proportions and adjusted hazard ratios computed from Cox regression analysis (reference: plasma Cbl of 200...

  6. Functional soy food based on flaxseed and quinoa and enriched with iron and Vitamin B12

    Directory of Open Access Journals (Sweden)

    Ana Carolina Braga

    2015-07-01

    Full Text Available A diet rich in food derived from vegetables reduces the risk of developing chronic and degenerative diseases and provides the essential nutrients for human consumption. Besides soybean, other foods of vegetal origin have been studied and incorporated in healthy formulations, such as quinoa and linseed. Current assay comprises a sensorial analysis of a product of vegetable origin, a soy product, based on quinoa and flaxseed, considered to be functional food, for its organoleptic characteristics acceptable by a sample group of 80 individuals. Several tests were conducted to reach an adequate formulation for the product, characterized by 11.1 g of protein content, 9.6 g of dietary fiber and low levels of lipids, since it had only 1.4 g. The resulting product revealed adequate microbiological conditions when subjected to microbiological analysis (coliforms at 45ºC; coliforms at 35ºC and Staphylococcus aureus. According to scores in the sensory analysis, it may be assumed that the product was accepted by the sample group. The favorable results indicate the possibility of consumers adhering to a processed diet rich in food derived from vegetables, with functional properties, to replace animal-derived food which is rich in saturated fats and low in fiber.

  7. Vitamin B12 sources and bioavailability.

    Science.gov (United States)

    Watanabe, Fumio

    2007-11-01

    The usual dietary sources of vitamin B(12) are animal foods, meat, milk, egg, fish, and shellfish. As the intrinsic factor-mediated intestinal absorption system is estimated to be saturated at about 1.5-2.0 microg per meal under physiologic conditions, vitamin B(12) bioavailability significantly decreases with increasing intake of vitamin B(12) per meal. The bioavailability of vitamin B(12) in healthy humans from fish meat, sheep meat, and chicken meat averaged 42%, 56%-89%, and 61%-66%, respectively. Vitamin B(12) in eggs seems to be poorly absorbed (vitamin B(12) is absorbed by healthy adults with normal gastro-intestinal function. Some plant foods, dried green and purple lavers (nori) contain substantial amounts of vitamin B(12), although other edible algae contained none or only traces of vitamin B(12). Most of the edible blue-green algae (cyanobacteria) used for human supplements predominantly contain pseudovitamin B(12), which is inactive in humans. The edible cyanobacteria are not suitable for use as vitamin B(12) sources, especially in vegans. Fortified breakfast cereals are a particularly valuable source of vitamin B(12) for vegans and elderly people. Production of some vitamin B(12)-enriched vegetables is also being devised.

  8. Vitamin B12 level

    Science.gov (United States)

    ... B12 in diet (rare, except with a strict vegetarian diet) Diseases that cause malabsorption (for example, celiac disease and Crohn disease ) Lack of intrinsic factor , a protein that helps the intestine absorb vitamin B12 Above normal heat production (for example, with hyperthyroidism ) ...

  9. The status of vitamin B12 and folate among Chinese women: a population-based cross-sectional study in northwest China.

    Science.gov (United States)

    Dang, Shaonong; Yan, Hong; Zeng, Lingxia; Wang, Quanli; Li, Qiang; Xiao, Shengbin; Fan, Xiaojing

    2014-01-01

    To assess the status of the vitamin B12 and folate of Chinese women living in northwest China. A population-based cross-sectional study was conducted in 2008 among Chinese women aged 10-49 years living in Shaanxi province of northwest China. A stratified multistage random sampling method was adopted to obtain a sample of 1170 women. The women were interviewed for collection of their background information and their plasma vitamin B12 and folate were measured with the immunoassay method. The status of both vitamins was evaluated and the prevalence of deficiency was estimated. The median value of the women was 214.5 pg/mL for vitamin B12 and 4.6 ng/mL for folate. The urban women had a significantly higher vitamin B12 (254.1 vs. 195.9 pg/mL) but lower folate (4.4 vs. 4.7 ng/mL) than rural women. Total prevalence of deficiency was 45.5% (95% CI: 42.6% ∼ 48.4%) for vitamin B12 and 14.7% (95% CI: 12.6% ∼ 16.8%) for folate. About 36% of women presented vitamin B12 deficiency alone, 5.2% belonged to folate deficiency alone and 9.5% was combined deficiency in both vitamins. More than 25% of the women were in marginal vitamin B12 status (200-299 pg/mL) and 60% in marginal status of folate (3-6 ng/mL). About 75.2% of rural women with folate deficiency were deficient in vitamin B12 and 46% for urban women. Quantile regression model found decreasing coefficient of folate status across 73 different quantiles of vitamin B12, which indicated that the women with folate deficiency had lower vitamin B12 significantly compared with those with no deficiency. The deficiency of vitamin B12 and folate is still prevalent among the Chinese women in northwest China. Vitamin B12 deficiency could be more serious and the improvement of poor vitamin B12 status should be invoked when practicing the supplementation of folate against the neural tube defects in northwest China.

  10. Anemia - B12 deficiency

    Science.gov (United States)

    ... done include: Complete blood count ( CBC ) Reticulocyte count Lactate dehydrogenase ( LDH ) level Vitamin B12 level Methylmalonic acid ( ... Updated by: Todd Gersten, MD, Hematology/Oncology, Florida Cancer Specialists & Research Institute, Wellington, FL. Review provided by ...

  11. Vitamin B12

    Science.gov (United States)

    ... fortified. You can get the recommended amounts of vitamin B12 by eating a variety of the foods including: Organ meats (beef liver) Shellfish (clams) Meat, poultry, eggs, milk and other dairy foods Some breakfast cereals and ...

  12. Vitamin B12 and Cognitive Function

    Science.gov (United States)

    2013-01-01

    Background More than 2.9 million serum vitamin B12 tests were performed in 2010 in Ontario at a cost of $40 million. Vitamin B12 deficiency has been associated with a few neurocognitive disorders. Objective To determine the clinical utility of B12 testing in patients with suspected dementia or cognitive decline. Methods Three questions were addressed: Is there an association between vitamin B12 deficiency and the onset of dementia or cognitive decline? Does treatment with vitamin B12 supplementation improve cognitive function in patients with dementia or cognitive decline and vitamin B12 deficiency? What is the effectiveness of oral versus parenteral vitamin B12 supplementation in those with confirmed vitamin B12 deficiency? A literature search was performed using MEDLINE, Embase, EBSCO Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the Centre for Reviews and Dissemination database, from January 2002 until August 2012. Results Eighteen studies (7 systematic reviews and 11 observational studies) were identified to address the question of the association between B12 and the onset of dementia. Four systematic reviews were identified to address the question of the treatment of B12 on cognitive function. Finally, 3 randomized controlled trials were identified that compared oral B12 to intramuscular B12. Conclusions Based on very low quality evidence, there does appear to be an association between elevated plasma homocysteine levels (a by-product of B vitamins) and the onset of dementia. Based on moderate quality evidence, but with less than optimal duration of follow-up, treatment with B12 supplementation does not appreciably change cognitive function. Based on low to moderate quality of evidence, treatment with vitamin B12 and folate in patients with mild cognitive impairment seems to slow the rate of brain atrophy. Based on moderate quality evidence, oral vitamin B12 is as effective as parenteral vitamin B12 in patients with

  13. Biologically active vitamin B12 compounds in foods for preventing deficiency among vegetarians and elderly subjects.

    Science.gov (United States)

    Watanabe, Fumio; Yabuta, Yukinori; Tanioka, Yuri; Bito, Tomohiro

    2013-07-17

    The usual dietary sources of vitamin B12 are animal-source based foods, including meat, milk, eggs, fish, and shellfish, although a few plant-based foods such as certain types of dried lavers (nori) and mushrooms contain substantial and considerable amounts of vitamin B12, respectively. Unexpectedly, detailed characterization of vitamin B12 compounds in foods reveals the presence of various corrinoids that are inactive in humans. The majority of edible blue-green algae (cyanobacteria) and certain edible shellfish predominately contain an inactive corrinoid known as pseudovitamin B12. Various factors affect the bioactivity of vitamin B12 in foods. For example, vitamin B12 is partially degraded and loses its biological activity during cooking and storage of foods. The intrinsic factor-mediated gastrointestinal absorption system in humans has evolved to selectively absorb active vitamin B12 from naturally occurring vitamin B12 compounds, including its degradation products and inactive corrinoids that are present in daily meal foods. The objective of this review is to present up-to-date information on various factors that can affect the bioactivity of vitamin B12 in foods. To prevent vitamin B12 deficiency in high-risk populations such as vegetarians and elderly subjects, it is necessary to identify plant-source foods that contain high levels of bioactive vitamin B12 and, in conjunction, to prepare the use of crystalline vitamin B12-fortified foods.

  14. Gastric status and vitamin B12 levels in cardiovascular patients.

    NARCIS (Netherlands)

    Oijen, M.G.H. van; Sipponen, P.; Laheij, R.J.F.; Verheugt, F.W.A.; Jansen, J.B.M.J.

    2007-01-01

    Proper absorption of vitamin B12 requires gastric corpus mucosa that functions appropriately and secretes intrinsic factor needed as an essential cofactor for the absorption of dietary vitamin B12 in the small bowel. Here we describe the prevalence of vitamin B12 deficiency and atrophic corpus

  15. Effect of a Klamath algae product ("AFA-B12") on blood levels of vitamin B12 and homocysteine in vegan subjects: a pilot study.

    Science.gov (United States)

    Baroni, Luciana; Scoglio, Stefano; Benedetti, Serena; Bonetto, Chiara; Pagliarani, Silvia; Benedetti, Yanina; Rocchi, Marco; Canestrari, Franco

    2009-03-01

    Vitamin B12 is a critical nutrient that is often inadequate in a plant-based (vegan) diet, thus the inclusion of a reliable vitamin B12 source in a vegan diet is recommended as essential. Unfortunately, many natural sources of vitamin B12 have been proven to contain biologically inactive vitamin B12 analogues, inadequate for human supplementation. The aim of this non-randomized open trial was to determine whether supplementation with a natural Klamath algae-based product ("AFA-B12", Aphanizomenon flos-aquae algae plus a proprietary mix of enzymes) could favorably affect the vitamin B12 status of a group of 15 vegan subjects. By assessing blood concentration of vitamin B12, folate, and more importantly homocysteine (Hcy, a reliable marker in vegans of their B12 absorption), the vitamin B12 status of the participants at the end of the 3-month intervention period, while receiving the Klamath-algae supplement (T2), was compared with their vitamin B12 status at the end of the 3-month control period (T1), when they were not receiving any supplement, having stopped taking their usual vitamin B12 supplement at the beginning of the study (T0). Compared to the control period, in the intervention period participants improved their vitamin B12 status, significantly reducing Hcy blood concentration (p=0.003). In conclusion, the Klamath algae product AFA-B12 appears to be, in a preliminary study, an adequate and reliable source of vitamin B12 in humans.

  16. Staging vitamin B-12 (cobalamin) status in vegetarians.

    Science.gov (United States)

    Herbert, V

    1994-05-01

    When one stops eating vitamin B-12 (cobalamins), one passes through four stages of negative cobalamin balance: serum depletion [low holotranscobalamin II, ie, low vitamin B-12 on transcobalamin II (TCII)], cell depletion (decreasing holohaptocorrin and low red cell vitamin B-12 concentrations), biochemical deficiency (slowed DNA synthesis, elevated serum homocysteine and methylmalonate concentrations), and, finally, clinical deficiency (anemia). Serum vitamin B-12 is on two proteins: the circulating vitamin B-12 delivery protein, TCII, and the circulating vitamin B-12 storage protein, haptocorrin. Because TCII is depleted of vitamin B-12 within days after absorption stops, the best screening test for early negative vitamin B-12 balance is a measurement of vitamin B-12 on TCII (holoTCII). HoloTCII falls below the bottom of its normal range long before total serum vitamin B-12 (which is mainly vitamin B-12 on haptocorrin) falls below the bottom of its normal range.

  17. Amnionless function is required for cubilin brush-border expression and intrinsic factor-cobalamin (vitamin B12) absorption in vivo

    DEFF Research Database (Denmark)

    He, Qianchuan; Madsen, Mette; Kilkenney, Adam;

    2005-01-01

    Amnionless (AMN) and cubilin gene products appear to be essential functional subunits of an endocytic receptor called cubam. Mutation of either gene causes autosomal recessive Imerslund-Gräsbeck syndrome (I-GS, OMIM no. 261100) in humans, a disorder characterized by selective intestinal malabsorp......Amnionless (AMN) and cubilin gene products appear to be essential functional subunits of an endocytic receptor called cubam. Mutation of either gene causes autosomal recessive Imerslund-Gräsbeck syndrome (I-GS, OMIM no. 261100) in humans, a disorder characterized by selective intestinal...... malabsorption of cobalamin (vitamin B12) and urinary loss of several specific low-molecular-weight proteins. Vital insight into the molecular pathology of I-GS has been obtained from studies of dogs with a similar syndrome. In this work, we show that I-GS segregates in a large canine kindred due to an in...

  18. Total plasma homocysteine, folate, and vitamin b12 status in healthy Iranian adults: the Tehran homocysteine survey (2003–2004/a cross – sectional population based study

    Directory of Open Access Journals (Sweden)

    Bandarian Fatemeh

    2006-02-01

    Full Text Available Abstract Background Elevated plasma total homocysteine is an independent risk factor for cardiovascular disease and a sensitive marker of the inadequate vitamin B12 and folate insufficiency. Folate and vitamin B12 have a protective effect on cardiovascular disease. This population based study was conducted to evaluate the plasma total homocysteine, folate, and vitamin B12 in healthy Iranian individuals. Methods This study was a part of the Cardiovascular Risk Factors Survey in the Population Lab Region of Tehran University has been designed and conducted based on the methodology of MONICA/WHO Project. A total of 1214 people aged 25–64 years, were recruited and assessed regarding demographic characteristics, homocysteine, folate, and vitamin B12 levels with interview, questionnaires, examination and blood sampling. Blood samples were gathered and analyzed according to standard methods. Results The variables were assessed in 1214 participants including 428 men (35.3% and 786 women (64.7%. Age-adjusted prevalence of hyperhomocysteinemia (Hcy≥15 μmol/L was 73.1% in men and 41.07% in women (P Conclusion These results revealed that the prevalence of hyperhomocysteinemia, low folate and vitamin B12 levels are considerably higher than other communities. Implementation of preventive interventions such as food fortification with folic acid is necessary.

  19. Food-Like Growth Conditions Support Production of Active Vitamin B12 by Propionibacterium freudenreichii 2067 without DMBI, the Lower Ligand Base, or Cobalt Supplementation

    Science.gov (United States)

    Deptula, Paulina; Chamlagain, Bhawani; Edelmann, Minnamari; Sangsuwan, Panchanit; Nyman, Tuula A.; Savijoki, Kirsi; Piironen, Vieno; Varmanen, Pekka

    2017-01-01

    Propionibacterium freudenreichii is a traditional dairy bacterium and a producer of short chain fatty acids (propionic and acetic acids) as well as vitamin B12. In food applications, it is a promising organism for in situ fortification with B12 vitamin since it is generally recognized as safe (GRAS) and it is able to synthesize biologically active form of the vitamin. In the present study, vitamin B12 and pseudovitamin biosynthesis by P. freudenreichii was monitored by UHPLC as a function of growth in food-like conditions using a medium mimicking cheese environment, without cobalt or 5,6-dimethylbenzimidazole (DMBI) supplementation. Parallel growth experiments were performed in industrial-type medium known to support the biosynthesis of vitamin B12. The production of other key metabolites in the two media were determined by HPLC, while the global protein production was compared by gel-based proteomics to assess the effect of growth conditions on the physiological status of the strain and on the synthesis of different forms of vitamin. The results revealed distinct protein and metabolite production, which reflected the growth conditions and the potential of P. freudenreichii for synthesizing nutritionally relevant amounts of active vitamin B12 regardless of the metabolic state of the cells. PMID:28337185

  20. Amnionless function is required for cubilin brush-border expression and intrinsic factor-cobalamin (vitamin B12) absorption in vivo.

    Science.gov (United States)

    He, Qianchuan; Madsen, Mette; Kilkenney, Adam; Gregory, Brittany; Christensen, Erik I; Vorum, Henrik; Højrup, Peter; Schäffer, Alejandro A; Kirkness, Ewen F; Tanner, Stephan M; de la Chapelle, Albert; Giger, Urs; Moestrup, Søren K; Fyfe, John C

    2005-08-15

    Amnionless (AMN) and cubilin gene products appear to be essential functional subunits of an endocytic receptor called cubam. Mutation of either gene causes autosomal recessive Imerslund-Gräsbeck syndrome (I-GS, OMIM no. 261100) in humans, a disorder characterized by selective intestinal malabsorption of cobalamin (vitamin B12) and urinary loss of several specific low-molecular-weight proteins. Vital insight into the molecular pathology of I-GS has been obtained from studies of dogs with a similar syndrome. In this work, we show that I-GS segregates in a large canine kindred due to an in-frame deletion of 33 nucleotides in exon 10 of AMN. In a second, unrelated I-GS kindred, affected dogs exhibit a homozygous substitution in the AMN translation initiation codon. Studies in vivo demonstrated that both mutations abrogate AMN expression and block cubilin processing and targeting to the apical membrane. The essential features of AMN dysfunction observed in vivo are recapitulated in a heterologous cell-transfection system, thus validating the system for analysis of AMN-cubilin interactions. Characterization of canine AMN mutations that cause I-GS establishes the canine model as an ortholog of the human disorder well suited to studies of AMN function and coevolution with cubilin.

  1. SPR技术对奶粉中维生素B12检测方法的建立%Method establishment of testing vitamin B12 in milk powder based on surface plasmon resonance

    Institute of Scientific and Technical Information of China (English)

    孙明君; 陈雍硕; 郑小龙; 陈启

    2014-01-01

    Objective To establish a method of fast-testing vitamin B12 in milk by using the technique of surface plasmon resonance (SPR).MethodsVitamin B12was covalently coupled to laboratory prepared CM5 chip to obtain vitamin chip, the optimal antibody working concentration and chip regeneration conditions were investigated. Meanwhile, the stability of vitamin chip was measured. A series of different concentrations of vitamin B12 was added to blank milk samples to construct a standard curve for vitamin B12 quantification according to the principle of competitive immune inhibition assay. Ten commercial milk samples were determined by the developed method. ResultsVitamin chip displayed a good stability, and the relative standard deviation (RSD) for 50 cycles was less than 10%. The limit of detection (LOD) of vitamin B12 was 0.006μg/100 g, and recoveries were 92.1%~104.1%. Vitamin B12content below the required threshold level was not observed in 10 milk samples.ConclusionLess than 6 h was consumed for the determination of vitamin B12 by the developed method, this method could offer a simple and efficient approach for vitamin B12 quantification.%目的:利用表面等离子共振(surface plasmon resonance, SPR)技术,建立快速定量测定牛奶中维生素B12的方法。方法将钴胺素共价偶联到表面等离子共振芯片CM5表面,并对竞争结合的维生素B12结合蛋白的结合浓度及芯片的再生条件进行优化,检测芯片的稳定性。在无抗生素牛奶中添加系列质量浓度的维生素B12,利用免疫竞争抑制原理构建标准曲线,并对市售10个奶粉样品进行检测。结果制备的芯片稳定,50个循环相对标准偏差(relative standard deviation, RSD)小于10%。日间批内同一样品差异为0.54%,该方法的检测限为0.006μg/100 g,回收率为92.1%~104.1%。测得的10个牛奶产品中维生素B12含量与对应商品标签值全部在标准规定的范围内。结论所建立的方法可以在6 h内完成样

  2. [Approaches to vitamin B12 deficiency].

    Science.gov (United States)

    Russcher, Henk; Heil, Sandra G; Slobbe, Lennert; Lindemans, Jan

    2012-01-01

    A 28-year-old female vegetarian was referred to a specialist in internal medicine with persistent iron deficiency. Laboratory analysis revealed microcytic anaemia with low ferritin levels but normal total vitamin B12 levels. The red blood cell distribution width, however, showed a very wide variation in red blood cell sizes, indicating a coexisting vitamin B12 deficiency, which was confirmed by the low concentration of active vitamin B12. Another patient, a 69-year-old woman with a history of previous gastric surgery and renal insufficiency as a complication of diabetes mellitus, was suspected to be deficient in vitamin B12, as she had low total vitamin B12 levels and an accumulation of methylmalonic acid and homocysteine in her blood. Testing the total concentration of vitamin B12 alone has insufficient diagnostic accuracy and no accepted gold standard is available for diagnosing vitamin B12 deficiency. With the development of newer tests, such as measuring holotranscobalamin II (concentration of active vitamin B12), atypical and subclinical deficiency states can be recognized. A new approach to diagnosing vitamin B12 deficiency is presented, based upon these 2 case descriptions.

  3. Elevated Vitamin B12 Levels

    Directory of Open Access Journals (Sweden)

    Melike Sezgin Evim

    2014-12-01

    Full Text Available Vitamin B12 is essential to all cells in the body. Both high levels and low levels of vitamin B12 are significant. High serum cobalamin (vitamin B12 levels are found particularly in hematological disorders, solid tumors, autoimmune diseases, renal diseases and infectious diseases; and this elevation is associated with prognosis in some of these diseases. High levels of serum vitamin B12 should be taken into consideration and more studies should be performed on this issue.

  4. Organometallic B12-DNA conjugate

    DEFF Research Database (Denmark)

    Hunger, Miriam; Mutti, Elena; Rieder, Alexander

    2014-01-01

    Design, synthesis, and structural characterization of a B12-octadecanucleotide are presented herein, a new organometallic B12-DNA conjugate. In such covalent conjugates, the natural B12 moiety may be a versatile vector for controlled in vivo delivery of oligonucleotides to cellular targets in hum...

  5. B12 in fetal development.

    Science.gov (United States)

    Pepper, M Reese; Black, Maureen M

    2011-08-01

    Vitamin B12 (cobalamin) is necessary for development of the fetus and child. Pregnant women who are vegetarian or vegan, have Crohn's or celiac disease, or have undergone gastric bypass surgery are at increased risk of B12 deficiency. Low serum levels of B12 have been linked to negative impacts in cognitive, motor, and growth outcomes. Low cobalamin levels also may be related to depression in adults. Some studies indicate that B12 supplementation may improve outcomes in children, although more research is needed in this area. Overall, the mechanisms of B12 action in development remain unclear. Further studies in this area to elucidate the pathways of cobalamin influence on development, as well as to prevent B12 deficiency in pregnant women and children are indicated.

  6. Nutritional vitamin-B12 deficiency. Possible contributory role of subtle vitamin-B12 malabsorption.

    Science.gov (United States)

    Carmel, R

    1978-05-01

    Dietary deficiency of vitamin B-12 has been reported, yet most people ingesting vitamin-B12-deficient diets even for many years appear to achieve a balance that does not lead to overt signs and symptoms of deficiency. I present the case of a vegan of 25 years' duration who developed severe neurologic abnormalities due to vitamin-B12 deficiency. His diet provided 1.2 microgram of vitamin B12 daily at most. Despite normal Schilling test findings, he absorbed subnormal amounts of vitamin B12 given with ovalbumin. This poor absorption appeared to be related to his gastritis, achlorhydria, and subnormal intrinsic-factor secretion. Probably, vitamin-B12 deficiency in this patient resulted from both dietary restriction and the subtle malabsorption, neither of which would have sufficed alone to produce the clinical problem. Possibly such malabsorption may also be present in many of those vegans developing overt vitamin-B12 deficiency in whom Schilling test findings have been normal.

  7. Bioavailability of vitamin B12

    Science.gov (United States)

    Vitamin B12 deficiency is common in people of all ages who consume a low intake of animal-source foods, including populations in developing countries. It is also prevalent among the elderly, even in wealthier countries, due to their malabsorption of B12 from food. Several methods have been applied t...

  8. Effects of Vitamin B12 in Neonates and Young Infants

    Directory of Open Access Journals (Sweden)

    Gian Maria Pacifici

    2016-06-01

    Full Text Available Vitamin B12 (cobalamin is an essential coenzyme for nucleic acid synthesis. Animal protein is the major dietary source of vitamin B12. Deficiency of vitamin B12 leads to megaloblastic anemia, degeneration of the brain, spinal cord, peripheral nerves, and abnormalities of epithelial tissues. Two factors are necessary for the cure of megaloblastic anemia: one in food (extrinsic factor and one in gastric juice (intrinsic factor. The extrinsic factor is vitamin B12. Intrinsic factor (a glycoprotein secreted by gastric parietal cells ensures cobalamin absorption by receptors in the terminal ileum. Vitamin B12 is actively transported across the placenta. Neonates have high serum levels and significant liver stores of vitamin B12. The neonates born to mothers with deficiency of vitamin B12 have deficiency of this vitamin. Pregnant women in resource-poor areas have low vitamin B12 status which is associated with adverse pregnancy outcomes, including anemia, low birth weight, and intrauterine growth retardation. Supplementation of vitamin B12 had significantly higher plasma of vitamin B12 in mothers and neonates. A single intramuscularly injection of vitamin B12 of between 250 µg and 1mg and a dietary intake of 1 µg/kg per day vitamin B12 is sufficient to combat vitamin B12 deficiency. Mean DNA damage scores in infants with vitamin B12 deficiency and their mothers were significantly higher before than after supplementation with vitamin B12. There were correlations between the infants' and their mothers' DNA damage scores. The aim of this study is the review of the effects of vitamin B12 in neonates and young infants.

  9. Progress on the studies of vitamin B12%维生素B12的研究进展

    Institute of Scientific and Technical Information of China (English)

    吕颖坚; 黄俊明

    2012-01-01

    本文对维生素B12的吸收与代谢、缺乏原因及疾病、营养水平鉴定、人群维生素B12营养状况、食物强化的研究进展进行了综述,以期提高对维生素B12的认识和重视、为解决维生素B12缺乏人群的健康问题提供参考.%In order to improve the awareness and attention on the importance of vitamin Bl2and to provide reference for solving problems of vitamin B12 deficiency, this review concentrates on five aspects of studies on vitamin B12: absorption and metabolism of vitamin BI2; cause/outcome of deficiency; biomarkers and their application; vitamin B12 status; and supplementation and fortification.

  10. Vitamin B12-Containing Plant Food Sources for Vegetarians

    OpenAIRE

    Fumio Watanabe; Yukinori Yabuta; Tomohiro Bito; Fei Teng

    2014-01-01

    The usual dietary sources of Vitamin B12 are animal-derived foods, although a few plant-based foods contain substantial amounts of Vitamin B12. To prevent Vitamin B12 deficiency in high-risk populations such as vegetarians, it is necessary to identify plant-derived foods that contain high levels of Vitamin B12. A survey of naturally occurring plant-derived food sources with high Vitamin B12 contents suggested that dried purple laver (nori) is the most suitable Vitamin B12 source presently av...

  11. Detection of vitamin B12 deficiency in older people by measuring vitamin B12 or the active fraction of vitamin B12, holotranscobalamin

    DEFF Research Database (Denmark)

    Clarke, Robert; Sherliker, Paul; Hin, Harold

    2007-01-01

    BACKGROUND: Impaired vitamin B(12) function and decreased vitamin B(12) status have been associated with neurological and cognitive impairment. Current assays analyze total vitamin B(12) concentration, only a small percentage of which is metabolically active. Concentrations of this active component......, carried on holotranscobalamin (holoTC), may be of greater relevance than total vitamin B(12). METHODS: We compared the utility of serum holoTC with conventional vitamin B(12) for detection of vitamin B(12) deficiency in a population-based study of older people, using increased methylmalonic acid (MMA......) concentrations as a marker of metabolic vitamin B(12) deficiency in the overall population (n = 2403) and in subsets with normal (n = 1651) and abnormal (n = 752) renal function. RESULTS: Among all participants, 6% had definite (MMA >0.75 micromol/L) and 16% had probable (MMA >0.45 micromol/L) metabolic vitamin...

  12. Detection of vitamin B12 deficiency in older people by measuring vitamin B12 or the active fraction of vitamin B12, holotranscobalamin

    DEFF Research Database (Denmark)

    Clarke, Robert; Sherliker, Paul; Hin, Harold

    2007-01-01

    BACKGROUND: Impaired vitamin B(12) function and decreased vitamin B(12) status have been associated with neurological and cognitive impairment. Current assays analyze total vitamin B(12) concentration, only a small percentage of which is metabolically active. Concentrations of this active component......, carried on holotranscobalamin (holoTC), may be of greater relevance than total vitamin B(12). METHODS: We compared the utility of serum holoTC with conventional vitamin B(12) for detection of vitamin B(12) deficiency in a population-based study of older people, using increased methylmalonic acid (MMA......) concentrations as a marker of metabolic vitamin B(12) deficiency in the overall population (n = 2403) and in subsets with normal (n = 1651) and abnormal (n = 752) renal function. RESULTS: Among all participants, 6% had definite (MMA >0.75 micromol/L) and 16% had probable (MMA >0.45 micromol/L) metabolic vitamin...

  13. Vitamin B12. III. The assay of vitamin B12

    NARCIS (Netherlands)

    Lens, J.; Wijmenga, H.G.; Wolff, R.; Karlin, R.; Winkler, K.C.; Haan, P.G. de

    1952-01-01

    1. 1. After the addition of KCN, purified liver-extracts can be chromatographed on Al2O3, the vitamin B12 being collected as one single band which can be measured spectrophotometrically. 2. 2. The values, thus obtained, agree satisfactorily with those of the L. Leichmannii and a little less with th

  14. Vitamin B12. III. The assay of vitamin B12

    NARCIS (Netherlands)

    Lens, J.; Wijmenga, H.G.; Wolff, R.; Karlin, R.; Winkler, K.C.; Haan, P.G. de

    1952-01-01

    1. 1. After the addition of KCN, purified liver-extracts can be chromatographed on Al2O3, the vitamin B12 being collected as one single band which can be measured spectrophotometrically. 2. 2. The values, thus obtained, agree satisfactorily with those of the L. Leichmannii and a little less with

  15. Vitamin B12: Unique Metalorganic Compounds and the Most Complex Vitamins

    Directory of Open Access Journals (Sweden)

    Lucio Randaccio

    2010-04-01

    Full Text Available The chemistry and biochemistry of the vitamin B12 compounds (cobalamins, XCbl are described, with particular emphasis on their structural aspects and their relationships with properties and function. A brief history of B12, reveals how much the effort of chemists, biochemists and crystallographers have contributed in the past to understand the basic properties of this very complex vitamin. The properties of the two cobalamins, the two important B12 cofactors Ado- and MeCbl are described, with particular emphasis on how the Co-C bond cleavage is involved in the enzymatic mechanisms. The main structural features of cobalamins are described, with particular reference to the axial fragment. The structure/property relationships in cobalamins are summarized. The recent studies on base-off/base-on equilibrium are emphasized for their relevance to the mode of binding of the cofactor to the protein scaffold. The absorption, transport and cellular uptake of cobalamins and the structure of the B12 transport proteins, IF and TC, in mammals are reviewed. The B12 transport in bacteria and the structure of the so far determined proteins are briefly described. The currently accepted mechanisms for the catalytic cycles of the AdoCbl and MeCbl enzymes are reported. The structure and function of B12 enzymes, particularly the important mammalian enzymes methyltransferase (MetH and methyl-malonyl-coenzymeA mutase (MMCM, are described and briefly discussed. Since fast proliferating cells require higher amount of vitamin B12 than that required by normal cells, the study of B12 conjugates as targeting agents has recently gained importance. Bioconjugates have been studied as potential agents for delivering radioisotopes and NMR probes or as various cytotoxic agents towards cancer cells in humans and the most recent studies are described. Specifically, functionalized bioconjugates are used as “Trojan horses” to carry into the cell the appropriate antitumour or

  16. Vitamin B12 deficiency and gastric histopathology in older patients

    Institute of Scientific and Technical Information of China (English)

    KR Dholakia; TS Dharmarajan; D Yadav; S Oiseth; EP Norkus; CS Pitchumoni

    2005-01-01

    AIM: To compare upper gastric endoscopic and histopathologic findings in older adults in the presence and absence of B12 deficiency.METHODS: A prospective analysis of upper gastric endoscopic and gastric histopathologic findings from 30 newly identified B12-deficient patients (11 males,19 females) and 16 controls with normal B12 status (6males, 10 females) was performed. For all subjects, the indication for upper endoscopy and gastric biopsy were unrelated to B12 status. A single pathologist, blinded to B12 status, processed and interpreted the biopsy samples. Endoscopic and histopathologic findings were correlated with age, gender, hematocrit (Hct), MCV and B12 status.RESULTS: The B12-deficient group had significantly lower mean serum B12 levels compared to the controls (P<0.00005) while their mean Hct, MCV and serum albumin levels were similar. Iron deficiency (ferritinbased) was present in 21% of B12-deficient patients and intrinsic factor antibodies were present in29% (5/17) of B12-deficient patients. The endoscopic findings revealed significantly different rates of gastritis and atrophy between the B12-deficient and control groups (P= 0.017).B12-deficient patients had significantly less superficial gastritis (62% vs 94%) and significantly more atrophic gastritis (28% vs 0%) as compared to the controls (P= 0.039). Intestinal metaplasia was similar in both groups. Helicobacter pyloriinfection rates were similar in the B12-deficient patients and controls (40% vs31%).CONCLUSION: Significantly different endoscopic findings and types of gastritis could often be observed in the presence and absence of B12 deficiency. Atrophy,based on endoscopy, and atrophic gastritis, based on histopathology, suggest the presence of B12 deficiency.Gastric histopathology is not influenced by the age,gender, Hct or MCV of the patients.

  17. Vitamine B12- en foliumzuurdeficientie

    NARCIS (Netherlands)

    Nieweg, Hendrik Omgo

    1953-01-01

    Het ligt in de bedoeling in dit proefschrift een overzicht te geven van de indicaties en de resultaten van de toepassing van vitamine B12 en foliumzuur in de kliniek. Aan de hand van deze gegevens zullen enkele nieuwere inzichten in de pathogenese worden besproken en zal worden nagegaan, welke gevol

  18. Proteomics of vitamin B12 processing.

    Science.gov (United States)

    Hannibal, Luciana; DiBello, Patricia M; Jacobsen, Donald W

    2013-03-01

    The causes of cobalamin (B12, Cbl) deficiency are multifactorial. Whether nutritional due to poor dietary intake, or functional due to impairments in absorption or intracellular processing and trafficking events, the major symptoms of Cbl deficiency include megaloblastic anemia, neurological deterioration and in extreme cases, failure to thrive and death. The common biomarkers of Cbl deficiency (hyperhomocysteinemia and methylmalonic acidemia) are extremely valuable diagnostic indicators of the condition, but little is known about the changes that occur at the protein level. A mechanistic explanation bridging the physiological changes associated with functional B12 deficiency with its intracellular processers and carriers is lacking. In this article, we will cover the effects of B12 deficiency in a cblC-disrupted background (also referred to as MMACHC) as a model of functional Cbl deficiency. As will be shown, major protein changes involve the cytoskeleton, the neurological system as well as signaling and detoxification pathways. Supplementation of cultured MMACHC-mutant cells with hydroxocobalamin (HOCbl) failed to restore these variants to the normal phenotype, suggesting that a defective Cbl processing pathway produces irreversible changes at the protein level.

  19. 2-Butanol and butanone production in Saccharomyces cerevisiae through combination of a B12 dependent dehydratase and a secondary alcohol dehydrogenase using a TEV-based expression system.

    Directory of Open Access Journals (Sweden)

    Payam Ghiaci

    Full Text Available 2-Butanol and its chemical precursor butanone (methyl ethyl ketone--MEK are chemicals with potential uses as biofuels and biocommodity chemicals. In order to produce 2-butanol, we have demonstrated the utility of using a TEV-protease based expression system to achieve equimolar expression of the individual subunits of the two protein complexes involved in the B12-dependent dehydratase step (from the pdu-operon of Lactobacillus reuteri, which catalyze the conversion of meso-2,3-butanediol to butanone. We have furthermore identified a NADH dependent secondary alcohol dehydrogenase (Sadh from Gordonia sp. able to catalyze the subsequent conversion of butanone to 2-butanol. A final concentration of 4±0.2 mg/L 2-butanol and 2±0.1 mg/L of butanone was found. A key factor for the production of 2-butanol was the availability of NADH, which was achieved by growing cells lacking the GPD1 and GPD2 isogenes under anaerobic conditions.

  20. B12 Deficiency with Children

    Directory of Open Access Journals (Sweden)

    Selahattin Katar

    2007-01-01

    Full Text Available Aim of the study: to rewieved the clinical and laboratory properties of seven cases with megaloblastic anemia. Clinical and laboratory findings of seven cases with megaloblastic anemia are described. İt is determined that all of the patients received little or no animal products by nutritional history. Clinically apatite, malasia, headeche, otism, and parestheia in the lower extremities and foods were present in patients. On physical examination; four patients had glossit, four had hyporeflexia, one had ataxia. Folat level was normal and B12 vitamin level was low in all patients. The MCV (mean corpuscular volume was normal in three patients. Hypersegmentation of neutrophil was observed in all patients, leukopenia in two, and trombocytopenia was observed in one patient.Conclusion: it is suggested B12 vitamin deficiency in the patients that received little or no animal products by nutritional history. However, hypersegmentation of neutrophil in peripheral blood sample is an important finding for diagnosis of megaloblastic anemia.

  1. Vitamin B-12 deficiency%Vitamin B-12deficiency

    Institute of Scientific and Technical Information of China (English)

    Ben Hudson

    2011-01-01

    @@ An 85 year old man had a preoperative assessment for a knee replacement.His full blood count was normal apart from haemoglobin 95 g/L and mean corpuscular volume 105 fl.He drank no alcohol.Further testing showed that his vitamin B-12was low:90 pmol/L(reference range 160-800 pmol/L).Folate,ferritin,thyroid stimulating hormone,and liver function tests were normal.He had no other medical or surgical history and ate a balanced diet that includes meat.

  2. Determination of vitamin B12 in fortified bovine milk-based infant formula powder, fortified soya-based infant formula powder, vitamin premix, and dietary supplements by surface plasmon resonance: collaborative study.

    Science.gov (United States)

    Vyas, Pathik; O'Kane, Anthony A

    2011-01-01

    A collaborative study was conducted on an inhibition-based protein-binding assay using the Biacore Q biosensor instrument and the Biacore Qflex Kit Vitamin B12 PI. The samples studied included infant formula, cereals, premixes, vitamin tablets, dietary supplements, and baby food. The collaborative study, which involved 11 laboratories, demonstrated that the assay showed an RSDr of 1.59-27.8 and HorRat values for reproducibility of 0.34-1.89 in samples with levels ranging from ppm to ppb. The assay studied is a label-free protein binding-based assay that uses the principle of surface plasmon resonance (SPR) to measure the interaction between vitamin B12 and a specific binding protein. A Biacore Q biosensor uses this principle to detect binding directly at the surface of a sensor chip with a hydrophilic gold-dextran surface. The instrument passes a mixture of prepared sample extract and binding protein solution across a covalently immobilized vitamin B12 chip surface, and the response is given as free-binding protein as the mixture binds to the immobilized surface. This technique uses the specificity and robustness of the protein-ligand interaction to allow minimal sample preparation and a wide range of matrixes to be analyzed rapidly. The reagents and accessories needed to perform this assay are provided as the ready-to-use format "Qflex Kit Vitamin B12 PI." The method is intended for routine use in the quantitative determination of vitamin B12 (as cyanocobalamin) in a wide range of food products, dietary vitamin supplements, and multivitamin premixes.

  3. The distribution of total vitamin B12, holotranscobalamin, and the active vitamin B12 fraction in the first 5 weeks postpartum.

    Science.gov (United States)

    van der Woude, D A A; Pijnenborg, J M A; de Vries, J; van Wijk, E M

    2017-09-04

    Total vitamin B12 levels decrease significantly during pregnancy and recover to normal values within 8-week postpartum. Holotranscobalamin (holoTC) reflects the active part of vitamin B12 and has been shown to remain constant during pregnancy and postpartum. A mechanism of redistribution of vitamin B12 is suggested, with a shift toward holoTC if there is insufficient total vitamin B12 available. Our objective was to examine vitamin B12 deficiency and the active vitamin B12 fraction in postpartum women. Total vitamin B12 and holoTC were measured in 171 women within 48 hours (T0) and at 5 weeks (T5) postpartum. Vitamin B12 deficiency was defined as total vitamin B12 vitamin B12 fraction was defined as holoTC/total vitamin B12. Without intervention, vitamin B12 deficiency based on both serum total vitamin B12 and holoTC changed from 75% and 60%, to respectively 10% and 6% at T5. The fraction of active vitamin B12 was significant higher in vitamin B12 deficient women at both time points and across time (P vitamin B12 was only present in women with total vitamin B12 deficiency at T0. At T5, no high vitamin B12 fraction was found. The changes in total vitamin B12 levels seem to be based on a physiological changes rather than vitamin B12 deficiency. The results of this study confirm the hypothesis that a shift toward the metabolic active vitamin B12 (holoTC) occurs in women with insufficient available total vitamin B12. © 2017 John Wiley & Sons Ltd.

  4. Vitamine B12 en cognitieve functies

    NARCIS (Netherlands)

    Eussen, S.J.P.M.; Groot, de C.P.G.M.; Hoefnagels, W.H.L.; Staveren, van W.A.

    2004-01-01

    Vitamine B12-deficiëntie is een relatief veel voorkomend probleem bij ouderen. Wageningen Universiteit onderzoekt wat de optimale hoeveelheid vitamine B12 in capsules zou moeten zijn om een vitamine B12-deficiëntie te behandelen en of deze hoeveelheid B12 gunstige effecten heeft op het cognitief fun

  5. Vitamin B12-Containing Plant Food Sources for Vegetarians

    Science.gov (United States)

    Watanabe, Fumio; Yabuta, Yukinori; Bito, Tomohiro; Teng, Fei

    2014-01-01

    The usual dietary sources of Vitamin B12 are animal-derived foods, although a few plant-based foods contain substantial amounts of Vitamin B12. To prevent Vitamin B12 deficiency in high-risk populations such as vegetarians, it is necessary to identify plant-derived foods that contain high levels of Vitamin B12. A survey of naturally occurring plant-derived food sources with high Vitamin B12 contents suggested that dried purple laver (nori) is the most suitable Vitamin B12 source presently available for vegetarians. Furthermore, dried purple laver also contains high levels of other nutrients that are lacking in vegetarian diets, such as iron and n-3 polyunsaturated fatty acids. Dried purple laver is a natural plant product and it is suitable for most people in various vegetarian groups. PMID:24803097

  6. Vitamin B12-Containing Plant Food Sources for Vegetarians

    Directory of Open Access Journals (Sweden)

    Fumio Watanabe

    2014-05-01

    Full Text Available The usual dietary sources of Vitamin B12 are animal-derived foods, although a few plant-based foods contain substantial amounts of Vitamin B12. To prevent Vitamin B12 deficiency in high-risk populations such as vegetarians, it is necessary to identify plant-derived foods that contain high levels of Vitamin B12. A survey of naturally occurring plant-derived food sources with high Vitamin B12 contents suggested that dried purple laver (nori is the most suitable Vitamin B12 source presently available for vegetarians. Furthermore, dried purple laver also contains high levels of other nutrients that are lacking in vegetarian diets, such as iron and n-3 polyunsaturated fatty acids. Dried purple laver is a natural plant product and it is suitable for most people in various vegetarian groups.

  7. Metformin increases liver accumulation of vitamin B12 - An experimental study in rats

    DEFF Research Database (Denmark)

    Greibe, E; Miller, J W; Foutouhi, S H

    2013-01-01

    AIMS/HYPOTHESIS: Patients treated with metformin exhibit low levels of plasma vitamin B(12) (B(12)), and are considered at risk for developing B(12) deficiency. In this study, we investigated the effect of metformin treatment on B(12) uptake and distribution in rats. METHODS: Sprague Dawley rats (n...... that metformin has no decreasing effect on the B(12) absorption. CONCLUSIONS/INTERPRETATION: These results show that metformin treatment increases liver accumulation of B(12), thereby resulting in decreases in circulating B(12) and kidney accumulation of the vitamin. Our data questions whether the low plasma B......(12) observed in patients treated with metformin reflects impaired B(12) status, and rather suggests altered tissue distribution and metabolism of the vitamin....

  8. Bioavailability of dietary cyanocobalamin (vitamin B12) in growing pigs.

    Science.gov (United States)

    Matte, J J; Guay, F; Le Floc'h, N; Girard, C L

    2010-12-01

    The present project aimed to estimate bioavailability of dietary vitamin B(12), for which little information is available in growing pigs. Two approaches, each using 2 quantities of dietary cyanocobalamin, were compared; the first was based on whole body retention for 8 d and the second was based on nycthemeral portal net flux of vitamin B(12). In the first trial, 15 blocks of 3 pigs (31.7 ± 0.5 kg of BW) were formed according to their vitamin B(12) status. Within each block, 1 pig (CONT) was killed and tissues were sampled for vitamin B(12) determination. The remaining 2 piglets were fed 25 (B(12)-25) or 250 (B(12)-250) μg daily of cyanocobalamin for 8 d. Urine was sampled twice daily, and the pigs were killed and sampled as CONT pigs. The total content of vitamin B(12) in the carcass, urine, and intestinal tract was affected by the dietary treatments (P 0.019). The whole body retention of vitamin B(12) was greater (P = 0.02) in B(12)-250 than B(12)-25 pigs, but the corresponding bioavailability was estimated to be 5.3 and 38.2%, respectively. In trial 2, 11 pigs (35.1 ± 4.0 kg of BW and 75.4 ± 5.9 d of age) fed a diet unsupplemented with vitamin B(12) from weaning at 28 d of age were surgically equipped with catheters in the portal vein and carotid artery and an ultrasonic flow probe around the portal vein. Each pig received 3 boluses of 0 (B(12)-0), 25, and 250 μg of dietary vitamin B(12) according to a crossover design. Postprandial nycthemeral arterial plasma concentrations of vitamin B(12) reached minimum values (P < 0.01) between 15 and 18 h postmeal that were 29.6, 15.6, and 10.0% less than the premeal values for B(12)-0, B(12)-25, and B(12)-250 pigs, respectively (linear, P < 0.01). The cumulative net flux of vitamin B(12) for 24 h corresponded to 2.4 and 5.1 µg for B(12)-25 and B(12)-250 treatments, respectively, and the corresponding bioavailability was estimated to be 9.7 and 2.0%, respectively. Although bioavailability estimates varied according

  9. Vitamin B12 and Folate Test

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Vitamin B12 and Folate Share this page: Was this ... as: Cobalamin; Folic Acid; RBC Folate Formal name: Vitamin B12; Folate Related tests: Complete Blood Count , Methylmalonic ...

  10. How common is vitamin B12 deficiency?

    Science.gov (United States)

    In considering the vitamin B-12 fortification of flour, it is important to know who is at risk of vitamin B-12 deficiency and whether those individuals would benefit from flour fortification.This article reviews current knowledge of the prevalence and causes of vitamin B-12 deficiency and considers ...

  11. Vitamin B12 requirements in older adults

    NARCIS (Netherlands)

    Doets, Esmee; Groot, de C.P.G.M.

    2016-01-01

    This paper provides an overview of dose-response evidence relevant for estimating vitamin B12 requirements of healthy adults and elderly people, considering different indicators of health: vitamin B12 body stores, cognitive function, bone health, and biomarkers of vitamin B12 status.

    Vitami

  12. Vitamin B12 requirements in older adults

    NARCIS (Netherlands)

    Doets, Esmee; Groot, de C.P.G.M.

    2016-01-01

    This paper provides an overview of dose-response evidence relevant for estimating vitamin B12 requirements of healthy adults and elderly people, considering different indicators of health: vitamin B12 body stores, cognitive function, bone health, and biomarkers of vitamin B12

  13. 7 CFR 15b.12 - Discrimination prohibited.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 1 2010-01-01 2010-01-01 false Discrimination prohibited. 15b.12 Section 15b.12... ACTIVITIES RECEIVING FEDERAL FINANCIAL ASSISTANCE Employment Practices § 15b.12 Discrimination prohibited. (a... discrimination in employment under any program or activity receiving assistance from this Department. (2) A...

  14. 18 CFR 1b.12 - Transcripts.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Transcripts. 1b.12 Section 1b.12 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT OF ENERGY GENERAL RULES RULES RELATING TO INVESTIGATIONS § 1b.12 Transcripts. Transcripts, if any,...

  15. Bioavailability of dietary cyanocobalamin (vitamin B12) in growing pigs

    National Research Council Canada - National Science Library

    Matte, J J; Guay, F; Le Floc'h, N; Girard, C L

    2010-01-01

    .... Two approaches, each using 2 quantities of dietary cyanocobalamin, were compared; the first was based on whole body retention for 8 d and the second was based on nycthemeral portal net flux of vitamin B(12...

  16. Organometallic chemistry of b(12) coenzymes.

    Science.gov (United States)

    Kräutler, Bernhard

    2009-01-01

    When coenzyme B(12) was identified as organometallic derivative of vitamin B(12), metal-carbon bonds were revealed to be relevant in life processes. Vitamin B(12), the "antipernicious anaemia factor" required for human health, was isolated earlier as a crystallizable cyano-Co(III)-complex. B(12) cofactors and other cobalt corrinoids play important roles not only in humans, but in the metabolism of archaea and other microorganisms, in particular. Indeed, the microorganisms are the only natural sources of the B(12) derivatives. For other B(12)-requiring organisms the corrinoids are thus "vitamins". However, vitamin B(12) also needs to be converted into organometallic B(12)-forms, which are the typical coenzymes in metabolically important enzymes. One of these, methionine synthase, catalyzes the transfer of a methyl group and its corrinoid cofactor is methylcobalamin. Another one, methylmalonyl-CoA mutase uses a reversible radical process, and coenzyme B(12) (adenosylcobalamin) as its cofactor, to transform methylmalonyl-CoA into succinyl-CoA. In such enzymes, the bound B(12) derivatives engage (or are formed) in exceptional organometallic enzymatic reactions, which depend upon the organometallic reactivity of the B(12) cofactors. Clearly, organometallic B(12) derivatives hold an important position in life and have thus attracted particular interest from the medical sciences, biology, and chemistry. This chapter outlines the unique structures of B(12) derivatives and recapitulates their redox properties and their organometallic chemistry, relevant in the context of the metabolic transformation of B(12) derivatives into the relevant coenzyme forms and for their use in B(12)-dependent enzymes.

  17. Vitamin B12 in meat and dairy products.

    Science.gov (United States)

    Gille, Doreen; Schmid, Alexandra

    2015-02-01

    Vitamin B12 is synthesized exclusively by microorganisms; therefore, humans must absorb it from food. Excellent sources of B12 are foods of ruminant origin, so dairy and meat products play an important role in efforts to meet the official daily B12 intake recommendation of 3.0 μg. Concentrations of the vitamin vary within foods of ruminant origin, with the highest concentrations found in offal such as liver and kidney. In comparison, dairy products have much lower quantities of the vitamin. In bovine milk, the B12 concentration is stable with regard to breed, feed, season, and stage of lactation, but in ruminant meat, the amount of B12 can vary based on the feeding and husbandry of the animal as well as the cut of meat chosen and its preparation. Processing of ruminant food, including thermal treatment, usually diminishes the vitamin B12 concentration. This review summarizes the vitamin B12 content of foods and discusses the impact of food processing on vitamin content. The contribution of ruminant food sources to B12 intake is specifically evaluated, with its bioavailability taken into account. © The Author(s) 2015. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  18. Vitamin B12 Status in Children with Cystic Fibrosis and Pancreatic Insufficiency

    Science.gov (United States)

    Maqbool, Asim; Schall, Joan I.; Mascarenhas, Maria R.; Dougherty, Kelly A.; Stallings, Virginia A.

    2014-01-01

    Objective Unexpectedly high serum B12 concentrations were noted in most study subjects with cystic fibrosis (CF) and pancreatic insufficiency (PI) participating in a nutrition intervention at the baseline evaluation. The objectives of this study were to determine dietary, supplement-based and enzyme-based B12 intake, serum B12 concentrations, and predictors of vitamin B12 status in children with CF and PI. Study Design Serum B12 status was assessed in subjects (5-18 yrs) and categorized as elevated (Hi-B12) or within reference range (RR-B12) for age and sex. Serum homocysteine, plasma B6, red blood cell folate, height, weight, and body mass index Z scores, pulmonary function, energy, dietary and supplement-based vitamin intake were assessed. Results 106 subjects, mean age 10.4 ± 3.0 years participated. Median serum B12 was 1083 pg/ml, with 56% in the Hi-B12 group. Dietary and supplement-based B12 intake were both high representing 376% and 667% Recommended Dietary Allowance (RDA). The Hi-B12 group had significantly greater supplement-based B12 intake than the RR-B12 group (1000 vs. 583% RDA, p12 years increased risk for Hi-B12, while higher FEV1 decreased risk (Pseudo-R2=0.18, P<0.001). Conclusions Serum B12 was elevated in the majority of children with CF and PI. Supplement-based B12 intake was 6 to 10 times the RDA, and strongly predicted elevated serum B12 status. The health consequences of lifelong high supplement-based B12 intake and high serum B12 are unknown and require further study, as does the inversed correlation between serum B12 and FEV1. PMID:24445504

  19. Examining the Association between Vitamin B12 Deficiency and Dementia in High-Risk Hospitalized Patients.

    Science.gov (United States)

    Siswanto, O; Smeall, K; Watson, T; Donnelly-Vanderloo, M; O'Connor, C; Foley, N; Madill, J

    2015-12-01

    To explore the association between vitamin B12 deficiency and dementia in patients at high risk for vitamin B12 deficiency. Chart review. Emergency, critical care/ trauma, neurology, medicine, and rehabilitation units of two hospitals in Southwestern Ontario, Canada. Adult patients (n = 666) admitted from 2010 to 2012. Data collection included: reason for admission, gender, age, clinical signs and symptoms of B12 deficiency, serum B12 concentration, and B12 supplementation. Patients with dementia were identified based on their medication profile and medical history. Vitamin B12 deficiency (pmol/L) was defined as serum B12 concentration 220. Comparisons between B12-deficient patients with and without dementia were examined using parametric and non-parametric tests. Serum B12 values were available for 60% (399/666) of the patients, of whom 4% (16/399) were B12-deficient and 14% (57/399) were marginally deficient. Patients with dementia were not more likely to be B12-deficient or marginally deficient [21% (26/121)] compared to those with no dementia [17% (47/278), p=0.27)]. Based on documentation, 34% (25/73) of the B12-deficient and marginally-deficient patients did not receive B12 supplementation, of whom 40% (10/25) had dementia. In this sample of patients, there was no association between B12 deficiency and dementia. However, appropriate B12 screening protocols are necessary for high risk patient to identify deficiency and then receive B12 supplementation as needed.

  20. Laboratory assessment of vitamin B12 status.

    Science.gov (United States)

    Harrington, Dominic J

    2017-02-01

    The detection and correction of vitamin B12 (B12) deficiency prevents megaloblastic anaemia and potentially irreversible neuropathy and neuropsychiatric changes. B12 status is commonly estimated using the abundance of the vitamin in serum, with ∼148 pmol/L (200 ng/L) typically set as the threshold for diagnosing deficiency. Serum B12 assays measure the sum of haptocorrin-bound and transcobalamin-bound (known as holotranscobalamin) B12 It is only holotranscobalamin that is taken up by cells to meet metabolic demand. Although receiver operator characteristic curves show holotranscobalamin measurement to be a moderately more reliable marker of B12 status than serum B12, both assays have an indeterminate range. Biochemical evidence of metabolic abnormalities consistent with B12 insufficiency is frequently detected despite an apparently sufficient abundance of the vitamin. Laboratory B12 status markers that reflect cellular utilisation rather than abundance are available. Two forms of B12 act as coenzymes for two different reactions. Methionine synthase requires methylcobalamin for the remethylation of methionine from homocysteine. A homocysteine concentration >20 µmol/L may suggest B12 deficiency in folate-replete patients. In the second B12-dependent reaction, methylmalonyl-CoA mutase uses adenosylcobalamin to convert methylmalonyl-CoA to succinyl-CoA. In B12 deficiency excess methylmalonyl-CoA is hydrolysed to methylmalonic acid. A serum concentration >280 nmol/L may suggest suboptimal status in young patients with normal renal function. No single laboratory marker is suitable for the assessment of B12 status in all patients. Sequential assay selection algorithms or the combination of multiple markers into a single diagnostic indicator are both approaches that can be used to mitigate inherent limitations of each marker when used independently.

  1. Forms and Amounts of Vitamin B12 in Infant Formula: A Pilot Study

    OpenAIRE

    Greibe, Eva; Nexo, Ebba

    2016-01-01

    Purpose Infant formula is based on cow’s milk and designed to mimic breast milk for substitution. Vitamin B12 (B12) is bound to proteins in both breast milk and cow’s milk, and in milk from both species the vitamin occurs mainly in its natural form such as hydroxo-B12 with little or no synthetic B12 (cyano-B12). Here we test commercially available infant formulas. Methods Eleven commercially available infant formulas were measured for content of B12 and analyzed for the presence of B12-bindin...

  2. Vitamin B12 in Health and Disease

    Directory of Open Access Journals (Sweden)

    Fiona O’Leary

    2010-03-01

    Full Text Available Vitamin B12 is essential for DNA synthesis and for cellular energy production. This review aims to outline the metabolism of vitamin B12, and to evaluate the causes and consequences of sub-clinical vitamin B12 deficiency. Vitamin B12 deficiency is common, mainly due to limited dietary intake of animal foods or malabsorption of the vitamin. Vegetarians are at risk of vitamin B12 deficiency as are other groups with low intakes of animal foods or those with restrictive dietary patterns. Malabsorption of vitamin B12 is most commonly seen in the elderly, secondary to gastric achlorhydria. The symptoms of sub-clinical deficiency are subtle and often not recognized. The long-term consequences of sub-clinical deficiency are not fully known but may include adverse effects on pregnancy outcomes, vascular, cognitive, bone and eye health.

  3. [Therapy of hyperhomocysteinemia with vitamin B12].

    Science.gov (United States)

    Krajcovicová-Kudlácková, M; Blazícek, P; Sebeková, K; Valachovicová, M

    2002-11-01

    Prevalence of mild hyperhomocysteinemia in vegetarians and vegans is a consequence of vitamin B12 deficiency. Clinical study of homocysteine reduction by vitamin B12 consisted of subjective healthy adults on alternative nutrition (n = 9) with vitamin B12 deficiency and with mild hyperhomocysteinemia. Vitamin B12 treatment was implemented by 5 intramuscular cyanocobalamin injections of a total content of 2200 micrograms during two weeks. Homocysteine level was significantly reduced (from 22 mumol/l to 11.7 mumol/l; individual reduction 29-55%). Vitamin B12 concentration in blood was significantly increased (from 152 pmol/l to 277 pmol/l; individual % of increase 63-150). The results show a high effect of vitamin B12 treatment in homocysteine value reduction of subjects on alternative nutrition.

  4. [Vitamin B12 deficiency in the elderly].

    Science.gov (United States)

    Leischker, A H; Kolb, G F

    2015-01-01

    The prevalence of vitamin B12 deficiency increases with age. Patients with dementia and spouses of patients with dementia are at special risk for the development of vitamin B12 deficiency. In a normal diet this vitamin is present only in animal source foods; therefore, vegans frequently develop vitamin B12 deficiency if not using supplements or foods fortified with cobalamin. Apart from dementia, most of these manifestations are completely reversible under correct therapy; therefore it is crucial to identify and to treat even atypical presentations of vitamin B12 deficiency as early as possible. This article deals with the physiology and pathophysiology of vitamin B12 metabolism. A practice-oriented algorithm which also considers health economic aspects for a rational laboratory diagnosis of vitamin B12 deficiency is presented. In cases with severe neurological symptoms, therapy should be parenteral, especially initially. For parenteral treatment, hydroxocobalamin is the drug of choice.

  5. Accurate prediction of hard-sphere virial coefficients B6 to B12 from a compressibility-based equation of state

    Science.gov (United States)

    Hansen-Goos, Hendrik

    2016-04-01

    We derive an analytical equation of state for the hard-sphere fluid that is within 0.01% of computer simulations for the whole range of the stable fluid phase. In contrast, the commonly used Carnahan-Starling equation of state deviates by up to 0.3% from simulations. The derivation uses the functional form of the isothermal compressibility from the Percus-Yevick closure of the Ornstein-Zernike relation as a starting point. Two additional degrees of freedom are introduced, which are constrained by requiring the equation of state to (i) recover the exact fourth virial coefficient B4 and (ii) involve only integer coefficients on the level of the ideal gas, while providing best possible agreement with the numerical result for B5. Virial coefficients B6 to B10 obtained from the equation of state are within 0.5% of numerical computations, and coefficients B11 and B12 are within the error of numerical results. We conjecture that even higher virial coefficients are reliably predicted.

  6. Mendelian randomisation study of the associations of vitamin B12 and folate genetic risk scores with blood pressure and fasting serum lipid levels in three Danish population-based studies

    DEFF Research Database (Denmark)

    Husemoen, L L N; Skaaby, T; Thuesen, B H

    2016-01-01

    BACKGROUND/OBJECTIVES: The aim was to examine the association of genetic risk scores (GRSs) of vitamin B12 and folate-associated variants with blood pressure and lipids. SUBJECTS/METHODS: The study included 12 532 adults from three population-based studies (Inter99, Health2006 and Dan-MONICA10.......017), but not with blood pressure, triglyceride, and low-density lipoprotein and total cholesterol levels. CONCLUSIONS: GRSs were not associated with blood pressure and lipid levels, except for an association between the GRS for folate and HDL cholesterol. Further studies are needed to determine whether a causal...... and folate, respectively. The β coefficients (95% confidence interval (CI), P-value) for regression of log-transformed serum B12/folate on the weighted GRSs were 0.57 (0.54, 0.61), Pblood pressure...

  7. Nanofibrous membrane-based absorption refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Isfahani, RN; Sampath, K; Moghaddam, S

    2013-12-01

    This paper presents a study on the efficacy of highly porous nanofibrous membranes for application in membrane-based absorbers and desorbers. Permeability studies showed that membranes with a pore size greater than about one micron have a sufficient permeability for application in the absorber heat exchanger. Membranes with smaller pores were found to be adequate for the desorber heat exchanger. The membranes were implemented in experimental membrane-based absorber and desorber modules and successfully tested. Parametric studies were conducted on both absorber and desorber processes. Studies on the absorption process were focused on the effects of water vapor pressure, cooling water temperature, and the solution velocity on the absorption rate. Desorption studies were conducted on the effects of wall temperature, vapor and solution pressures, and the solution velocity on the desorption rate. Significantly higher absorption and desorption rates than in the falling film absorbers and desorbers were achieved. Published by Elsevier Ltd.

  8. Identification of differentially expressed proteins in vitamin B 12

    Directory of Open Access Journals (Sweden)

    Swati Varshney

    2015-01-01

    Full Text Available Background: Vitamin B 12 (cobalamin is a water-soluble vitamin generally synthesized by microorganisms. Mammals cannot synthesize this vitamin but have evolved processes for absorption, transport and cellular uptake of this vitamin. Only about 30% of vitamin B 12 , which is bound to the protein transcobalamin (TC (Holo-TC [HoloTC] enters into the cell and hence is referred to as the biologically active form of vitamin B 12 . Vitamin B 12 deficiency leads to several complex disorders, including neurological disorders and anemia. We had earlier shown that vitamin B 12 deficiency is associated with coronary artery disease (CAD in Indian population. In the current study, using a proteomics approach we identified proteins that are differentially expressed in the plasma of individuals with low HoloTC levels. Materials and Methods: We used isobaric-tagging method of relative and absolute quantitation to identify proteins that are differently expressed in individuals with low HoloTC levels when compared to those with normal HoloTC level. Results: In two replicate isobaric tags for relative and absolute quantitation experiments several proteins involved in lipid metabolism, blood coagulation, cholesterol metabolic process, and lipoprotein metabolic process were found to be altered in individuals having low HoloTC levels. Conclusions: Our study indicates that low HoloTc levels could be a risk factor in the development of CAD.

  9. Biochemistry, function, and deficiency of vitamin B12 in Caenorhabditis elegans.

    Science.gov (United States)

    Bito, Tomohiro; Watanabe, Fumio

    2016-09-01

    Caenorhabditis elegans is a nematode that has been widely used as an animal for investigation of diverse biological phenomena. Vitamin B12 is essential for the growth of this worm, which contains two cobalamin-dependent enzymes, methylmalonyl-CoA mutase and methionine synthase. A full complement of gene homologs encoding the enzymes associated with the mammalian intercellular metabolic processes of vitamin B12 is identified in the genome of C elegans However, this worm has no orthologs of the vitamin B12-binders that participate in human intestinal absorption and blood circulation. When the worm is treated with a vitamin B12-deficient diet for five generations (15 days), it readily develops vitamin B12 deficiency, which induces worm phenotypes (infertility, delayed growth, and shorter lifespan) that resemble the symptoms of mammalian vitamin B12 deficiency. Such phenotypes associated with vitamin B12 deficiency were readily induced in the worm.

  10. Generalised hyperpigmentation in vitamin B12 deficiency.

    Science.gov (United States)

    Santra, Gouranga; Paul, Rudrajit; Ghosh, Sumit Kr; Chakraborty, Debojyoti; Das, Shubhabrata; Pradhan, Sourav; Das, Abhishek

    2014-08-01

    In developing countries like India, nutritional deficiencies are prevalent and hyperpigmentation due to protein energy malnutrition, zinc deficiency and pellagra are common. Indian women, especially vegetarian are prone to vitamin B12 deficiency. Vitamin B12 deficiency can present as anaemia, neurological defect, gastrointestinal symptoms or dementia. Hyperpigmentation as the first presentation of Vitamin B12 deficiency is rare. Our patient, a 45 year-old Hindu vegetarian female presented to us with generalized hyperpigmentation. Examination revealed associated anaemia and peripheral neuropathy. Laboratory investigation confirmed vitamin B12 deficiency. Clinical features along with hyperpigmentation improved with vitamin B12 supplementation. We report this case to highlight this rare manifestation of vitamin B12 deficiency. A high index of clinical suspicion is warranted to diagnose the case. Since India is a country with a large number of potential vitamin B12 deficiency cases, the physicians need to be aware of all the varied manifestations of this vitamin deficiency. In case of hyperpigmentation, nutritional aspect must be ruled out as it is reversible. Early replacement therapy may also help to prevent morbidities like dementia and neuropathy.

  11. Two newborns with nutritional vitamin B12 deficiency: challenges in newborn screening for vitamin B12 deficiency.

    Science.gov (United States)

    Campbell, C D; Ganesh, J; Ficicioglu, C

    2005-12-01

    Vitamin B12 deficiency causes decreased Methionine Synthase and L-Methylmalonyl-CoA Mutase activity and results in accumulation of Homocysteine, Methylmalonic acid and Propionylcarnitine. Propionylcarnitine is included in tandem mass spectrometry-based newborn screening programs for detection of certain inborn errors of metabolism. We report two asymptomatic newborns with Vitamin B12 deficiency due to maternal deficiencies. One was detected incidentally at 3 weeks of age; the second on supplemental newborn screening based on elevated Propionylcarnitine at 2 days of age. This illustrates the potential for false negative results for Vitamin B12 deficiency screening by acylcarnitine profiling in newborn screening. Homocysteine and Methylmalonic acid may be better markers of Vitamin B12 deficiency. In conclusion, we suggest measuring Methylmalonic acid, Propionylcarnitine and Homocysteine levels in blood spots in expanded newborn screening in order to detect asymptomatic newborns with Vitamin B12 deficiency. Further studies are needed to establish the sensitivity of these three markers in screening for Vitamin B12 deficiency.

  12. Vitamin B12: advances and insights

    DEFF Research Database (Denmark)

    Obeid, Rima

    2017-01-01

    Vitamin B12 (cobalamin) constitutes an amazing area of research with many hidden facets. Key milestones in this area have been developed over 10 decades. This long process of trials and errors, and search and discoveries has radically changed our understanding for the role of this nutrient...... in health and diseases. The impact of vitamin B12 on human health has been shifted from ‘treatment’ of a deadly condition to ‘prevention’ of diseases. The importance of B12 has now taken global dimensions on a population level given the high prevalence of subclinical B12 deficiency that affects many...... individuals in critical life phases. This book has been written by experts who documented latest developments in the field. It is written for individuals looking for in depth knowledge of the nutritional, chemistry, biochemistry, health and medical relevance of the vitamin. The book provides insights...

  13. Vitamin B12 dan Anemia Megaloblastik

    OpenAIRE

    Harjani, Harjani

    2015-01-01

    Vitamin B12 is an essential factor for DNA synthesis, and it is also needed in the reaction for the production of lipoprotein in myelin sheaths of the nerve system.It is known that vitamin B12 deficiency causes.among others disturbances in the nucleus formation and leads to megaloblastic anemias, with or without disturbances of the peripheral nerve system. Disturbances in the nucleus formation affect cells of tissues which have a relatively rapid turnover such as hemopoiedc precursors in the ...

  14. Forms and Amounts of Vitamin B12 in Infant Formula: A Pilot Study

    DEFF Research Database (Denmark)

    Greibe, Eva; Nexø, Ebba

    2016-01-01

    PURPOSE: Infant formula is based on cow's milk and designed to mimic breast milk for substitution. Vitamin B12 (B12) is bound to proteins in both breast milk and cow's milk, and in milk from both species the vitamin occurs mainly in its natural form such as hydroxo-B12 with little or no synthetic B......12 (cyano-B12). Here we test commercially available infant formulas. METHODS: Eleven commercially available infant formulas were measured for content of B12 and analyzed for the presence of B12-binding proteins and forms of B12 using size exclusion chromatography and HPLC. RESULTS: All infant...... formulas contained B12 by and large in accord with the informations given on the package inserts. None of the formulas contained protein-bound B12, and cyano-B12 accounted for 19-78% of the total amount of B12 present, while hydroxo-B12 constituted more or less the rest. CONCLUSIONS: This pilot study shows...

  15. The association between vitamin B12, albuminuria and reduced kidney function: an observational cohort study

    OpenAIRE

    McMahon, Gearoid M.; Hwang, Shih-Jen; Rikki M Tanner; Jacques, Paul F.; Selhub, Jacob; Muntner, Paul; Fox, Caroline S.

    2015-01-01

    Background: Variants in CUBN, the gene encoding cubilin, a proximal tubular transport protein, have been associated with albuminuria and vitamin B12 (B12) deficiency. We hypothesized that low levels of B12 would be associated with albuminuria in a population-based cohort. Methods: We analyzed participants from the Framingham Heart Study (n = 2965, mean age 58 years, 53% female) who provided samples for plasma B12. Logistic regression models adjusted for covariates including homocysteine were ...

  16. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

    Science.gov (United States)

    Rizzo, Gianluca; Laganà, Antonio Simone; Rapisarda, Agnese Maria Chiara; La Ferrera, Gioacchina Maria Grazia; Buscema, Massimo; Rossetti, Paola; Nigro, Angela; Muscia, Vincenzo; Valenti, Gaetano; Sapia, Fabrizio; Sarpietro, Giuseppe; Zigarelli, Micol; Vitale, Salvatore Giovanni

    2016-01-01

    Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism. PMID:27916823

  17. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation.

    Science.gov (United States)

    Rizzo, Gianluca; Laganà, Antonio Simone; Rapisarda, Agnese Maria Chiara; La Ferrera, Gioacchina Maria Grazia; Buscema, Massimo; Rossetti, Paola; Nigro, Angela; Muscia, Vincenzo; Valenti, Gaetano; Sapia, Fabrizio; Sarpietro, Giuseppe; Zigarelli, Micol; Vitale, Salvatore Giovanni

    2016-11-29

    Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.

  18. Vitamin B12 among Vegetarians: Status, Assessment and Supplementation

    Directory of Open Access Journals (Sweden)

    Gianluca Rizzo

    2016-11-01

    Full Text Available Cobalamin is an essential molecule for humans. It acts as a cofactor in one-carbon transfers through methylation and molecular rearrangement. These functions take place in fatty acid, amino acid and nucleic acid metabolic pathways. The deficiency of vitamin B12 is clinically manifested in the blood and nervous system where the cobalamin plays a key role in cell replication and in fatty acid metabolism. Hypovitaminosis arises from inadequate absorption, from genetic defects that alter transport through the body, or from inadequate intake as a result of diet. With the growing adoption of vegetarian eating styles in Western countries, there is growing focus on whether diets that exclude animal foods are adequate. Since food availability in these countries is not a problem, and therefore plant foods are sufficiently adequate, the most delicate issue remains the contribution of cobalamin, which is poorly represented in plants. In this review, we will discuss the status of vitamin B12 among vegetarians, the diagnostic markers for the detection of cobalamin deficiency and appropriate sources for sufficient intake, through the description of the features and functions of vitamin B12 and its absorption mechanism.

  19. Peptide Paratope Mimics of the Broadly Neutralizing HIV-1 Antibody b12.

    Science.gov (United States)

    Haußner, Christina; Damm, Dominik; Nirschl, Sandra; Rohrhofer, Anette; Schmidt, Barbara; Eichler, Jutta

    2017-01-26

    The broadly neutralizing HIV-1 antibody b12 recognizes the CD4 binding site of the HIV-1 envelope glycoprotein gp120 and efficiently neutralizes HIV-1 infections in vitro and in vivo. Based on the 3D structure of a b12⋅gp120 complex, we have designed an assembled peptide (b12-M) that presents the parts of the three heavy-chain complementarity-determining regions (CDRs) of b12, which contain the contact sites of the antibody for gp120. This b12-mimetic peptide, as well as a truncated peptide presenting only two of the three heavy-chain CDRs of b12, were shown to recognize gp120 in a similar manner to b12, as well as to inhibit HIV-1 infection, demonstrating functional mimicry of b12 by the paratope mimetic peptides.

  20. Genetic determinants of serum vitamin B12 and their relation to body mass index

    DEFF Research Database (Denmark)

    Allin, Kristine H; Friedrich, Nele; Pietzner, Maik

    2016-01-01

    for associations between (1) serum vitamin B12 levels and body mass index (BMI), (2) genetic variants and serum vitamin B12 levels, and (3) genetic variants and BMI. The effect of a genetically determined decrease in serum vitamin B12 on BMI was estimated by instrumental variable regression. Decreased serum...... vitamin B12 associated with increased BMI (P genetic risk score based on eight vitamin B12 associated variants associated strongly with serum vitamin B12 (P ... was associated with a 0.09 kg/m(2) (95% CI 0.05; 0.13) increase in BMI (P = 3 × 10(-5)), whereas a genetically induced 20% decrease in serum vitamin B12 had no effect on BMI [-0.03 (95% CI -0.22; 0.16) kg/m(2)] (P = 0.74). Nevertheless, the strongest serum vitamin B12 variant, FUT2 rs602662, which was excluded...

  1. [Megaloblastic-vitamin B12 deficiency anemia in childhood].

    Science.gov (United States)

    Mtvarelidze, Z G; Kvezereli-Kopadze, A N; Kvezereli-Kopadze, M A

    2009-05-01

    Megaloblastic anemias are basically caused by vitamin B(12) and/or folic acid deficiency. Childhood vitamin B(12) deficiency is extremely rare. There are congenital and acquired forms of vitamin B(12)-deficiency anemias. The article captures findings of 10 year observation of 3 patients with Imerslund-Gräsbeck Syndrome (congenital chronic megaloblastic anemia with proteinuria), in which the diagnosis was established by us in early childhood and due to correct treatment and prevention complete clinical-laboratory remission is kept so far. We have also observed rare case of acquired megaloblastic anemia - 14 years old vegetarian patient, who was diagnosed with vitamin B(12)-deficiency anemia based on history, clinical and para-clinical data. It was caused by strict vegetarianism of the patient. Therefore first of all the diet was corrected. In 5 days of specific treatment with vitamin B(12) "reticulocyte crisis" was manifested (proving the correctness of diagnosis and treatment) and complete clinical-hematological remission was achieved in 2 weeks. The given cases are interesting as megaloblastic anemias in childhood are both rare and difficult to diagnose. In such cases timely diagnosis, treatment and prevention tactics should be based on cause-and-effect relation of disease.

  2. Holotranscobalamin (HoloTC, Active-B12) and Herbert's model for the development of vitamin B12 deficiency: a review and alternative hypothesis.

    Science.gov (United States)

    Golding, Paul Henry

    2016-01-01

    The concentration of total vitamin B12 in serum is not a sufficiently sensitive or specific indicator for the reliable diagnosis of vitamin B12 deficiency. Victor Herbert proposed a model for the staged development of vitamin B12 deficiency, in which holotranscobalamin (HoloTC) is the first indicator of deficiency. Based on this model, a commercial immunoassay has been controversially promoted as a replacement for the total vitamin B12 test. HoloTC is cobalamin (vitamin B12) attached to the transport protein transcobalamin, in the serum, for delivery to cells for metabolism. Although there have been many published reports supporting the claims for HoloTC, the results of some studies were inconsistent with the claim of HoloTC as the most sensitive marker of vitamin B12 deficiency. This review examines the evidence for and against the use of HoloTC, and concludes that the HoloTC immunoassay cannot be used to measure vitamin B12 status any more reliably than total vitamin B12, or to predict the onset of a metabolic deficiency, because it is based on an erroneous hypothesis and a flawed model for the staged development of vitamin B12 deficiency. The author proposes an alternative model for the development of vitamin B12 deficiency.

  3. Isolation and analysis of vitamin B12 from plant samples.

    Science.gov (United States)

    Nakos, M; Pepelanova, I; Beutel, S; Krings, U; Berger, R G; Scheper, T

    2017-02-01

    Based on increased demands of strict vegetarians, an investigation of vitamin B12 content in plant sources, was carried out. The vitamin B12 concentration was determined by RP-HPLC with UV detection, after prior matrix isolation by immunoaffinity chromatography (IAC). Vitamin B12 was extracted in the presence of sodium cyanide, to transform all forms of cobalamin into cyanocobalamin. Diode array detector was used to monitor vitamin B12, after its chromatographic separation under gradient elution with a mobile phase consisting of acetonitrile and trifluoroacetic acid 0.025% (w/v). The method demonstrated excellent linearity with a limit of detection 0.004μg/ml. The method precision was evaluated for plant samples and it was below 0.7% (n=6). Significant amounts of vitamin B12 in plants were detected in Hippophae rhamnoides (37μg/100g dry weight), in Elymus (26μg/100g dry weight) and in Inula helenium (11μg/100g dry weight).

  4. Dynamic behaviour of the B12 riboswitch

    Science.gov (United States)

    Santillán, Moisés; Mackey, Michael C.

    2005-03-01

    Riboswitches are RNA segments that serve as ligand-responsive genetic control elements. They modulate the expression of certain genes in response to changing concentrations of metabolites. In this paper, we study the dynamic behaviour of the B12 riboswitch in E. coli—perhaps the most widely studied and best known of all riboswitches—through a mathematical model of its regulatory pathway. To carry this out, we simulate dynamic experiments in which the bacterial B12 uptake capacity is measured after being depleted of this vitamin for a long time. The results of these simulations compare favourably with reported experimental data. The model also predicts that an overshoot of intracellular B12 should be observed if the replenishment experiments were to be carried out for longer times. This behaviour is discussed in terms of a possible evolutionary advantage for E. coli, together with the fact that regulation at the transcriptional and translational levels is almost equivalent dynamically.

  5. Preventing vitamin B12 deficiency in South Asian women of childbearing age: a randomised controlled trial comparing an oral vitamin B12 supplement with B12 dietary advice.

    Science.gov (United States)

    Mearns, G J; Koziol-McLain, J; Obolonkin, V; Rush, E C

    2014-08-01

    To examine the effectiveness, acceptability and sustainability of interventions to reduce vitamin B12 (B12) deficiency in South Asian women before conception. A 6-month randomised controlled trial conducted in Auckland, New Zealand. Participants (62 South Asian women, 18-50 years old) were stratified by dietary practices, then randomised to three treatment groups: B12 Supplement (oral cyanocobalamin 6 μg/day) (n=21), Placebo (n=21), or B12 Dietary Advice (n=20). Primary outcome measures were changes in B12 biomarkers (serum B12 and holotranscobalamin (holoTC)) at 6 months. Dietary B12 intake was estimated from a B12 food-specific frequency questionnaire (B12FFQ). Intention-to-treat analysis was applied using 'last observation carried forward' method. Changes in B12 biomarkers by treatment were compared using analysis of variance. Pearson's correlations tested relationships between dietary B12 intake and B12 biomarkers. At baseline, 48% of women tested as insufficient or deficient in serum B12 (B12 status was moderately correlated with dietary B12 intake (r=0.5, 95% confidence interval (CI) (0.3-0.7)) and 44% of women reported insufficient dietary intake (B12 Supplement was the only treatment group to record a significant increase in B12 biomarkers over 6 months: serum B12 by 30% (95% CI (11-48%)) and holoTC by 42% (12-72%). The prevalence of B12 insufficiency among Auckland South Asian women is high and moderately correlated with inadequate intake of foods that contain B12. Cyanocobalamin supplementation (6 μg/day) was associated with improved B12 biomarkers, with a potential to improve preconception B12 status in South Asian women.

  6. Folate, vitamin B12 and human health

    Science.gov (United States)

    During the past decade the role of folate and vitamin B12 in human nutrition have been under constant re-examination. Basic knowledge on the metabolism and interactions between these essential nutrients has expanded and multiple complexities have been unraveled. These micronutrients have shared func...

  7. Efficacy and safety of fortification and supplementation with vitamin B12: biochemical and physiological effects.

    Science.gov (United States)

    Carmel, Ralph

    2008-06-01

    Long known as an uncommon but serious medical disorder requiring medical management, vitamin B12 deficiency is now seen to be common worldwide, but it is in a quite different form than traditionally envisioned. Most of the newly recognized deficiency is subclinical in nature, its health impact and natural history are uncertain, and its prevalence has been greatly inflated by also including persons with "low-normal" vitamin B12 levels, few of whom are deficient. The spread of folic acid fortification has also introduced concerns about folate's potentially adverse neurologic consequences in persons with undetected vitamin B12 deficiency. Fortification with vitamin B12 may prove more complicated than fortification with folic acid, however, because the bioavailability of vitamin B12 is limited. Bioavailability for those who need the vitamin B12 the most is especially poor, because they often have malabsorption affecting either classical intrinsic factor-mediated absorption or food-vitamin B12 absorption. Moreover, new evidence shows that many elderly persons respond poorly to daily oral doses under 500 microg (1 microg = 0.74 nmol), even if they do not have classical malabsorption, which suggests that proposed fortification with 1 to 10 microg may be ineffective. Those least in need of vitamin B12 usually have normal absorption and are thus at greatest risk for whatever unknown adverse effects of high-dose fortification might emerge, such as the effects of excess accumulation of cyanocobalamin. Studies are needed to define the still unproven health benefits of vitamin B12 fortification, the optimal levels of fortification, the stability of such fortification, interactions with other nutrients, and any possible adverse effects on healthy persons. The answers will permit formulation of appropriately informed decisions about mandatory fortification or (because fortification may prove a poor choice) about targeted supplementation in subpopulations with special needs for

  8. [Vegetarians are at high risk of vitamin B12 deficiency].

    Science.gov (United States)

    Javid, Parva; Christensen, Erik

    2016-01-04

    Since vegetarians have a lower intake of vitamin B12 (B12) than non-vegetarians, they are at increased risk of developing B12 deficiency. The less animal products the food contains the worse the B12 status. However, even lacto-ovo-vegetarians run the risk of becoming deficient in B12. Vegetarians are recommended regularly to take supplements of B12, and they should be informed of the lacking content of B12 of plant products and the hazards of B12 deficiency. Furthermore, vegetarians should routinely be checked for possible B12 deficiency.

  9. Maximal load of the vitamin B12 transport system

    DEFF Research Database (Denmark)

    Lildballe, Dorte L; Mutti, Elena; Birn, Henrik

    2012-01-01

    Several studies suggest that the vitamin B12 (B12) transport system can be used for the cellular delivery of B12-conjugated drugs, also in long-term treatment Whether this strategy will affect the endogenous metabolism of B12 is not known. To study the effect of treatment with excess B12 or an in...

  10. Transcobalamin derived from bovine milk stimulates apical uptake of vitamin B12 into human intestinal epithelial cells.

    Science.gov (United States)

    Hine, Brad; Boggs, Irina; Green, Ralph; Miller, Joshua W; Hovey, Russell C; Humphrey, Rex; Wheeler, Thomas T

    2014-11-01

    Intestinal uptake of vitamin B12 (hereafter B12) is impaired in a significant proportion of the human population. This impairment is due to inherited or acquired defects in the expression or function of proteins involved in the binding of diet-derived B12 and its uptake into intestinal cells. Bovine milk is an abundant source of bioavailable B12 wherein it is complexed with transcobalamin. In humans, transcobalamin functions primarily as a circulatory protein, which binds B12 following its absorption and delivers it to peripheral tissues via its cognate receptor, CD320. In the current study, the transcobalamin-B12 complex was purified from cows' milk and its ability to stimulate uptake of B12 into cultured bovine, mouse and human cell lines was assessed. Bovine milk-derived transcobalamin-B12 complex was absorbed by all cell types tested, suggesting that the uptake mechanism is conserved across species. Furthermore, the complex stimulated the uptake of B12 via the apical surface of differentiated Caco-2 human intestinal epithelial cells. These findings suggest the presence of an alternative transcobalamin-mediated uptake pathway for B12 in the human intestine other than that mediated by the gastric glycoprotein, intrinsic factor. Our findings highlight the potential for transcobalamin-B12 complex derived from bovine milk to be used as a natural bioavailable alternative to orally administered free B12 to overcome B12 malabsorption.

  11. Serum vitamin B-12 concentrations within reference values do not exclude functional vitamin B-12 deficiency in PKU patients of various ages

    NARCIS (Netherlands)

    Vugteveen, Inge; Hoeksma, Marieke; Monsen, Anne-Lise Bjorke; Heiner-Fokkema, Rebecca; Reijngoud, Dirk-Jan; van Rijn, Margreet; van Spronsen, Francjan J.

    2011-01-01

    Homocysteine (Hcy) and in particular methylmalonic acid (MMA) are considered reliable parameters for vitamin B-12 status in healthy individuals. Phenylketonuria (PKU) patients are at risk for functional vitamin B-12 deficiency based on their diet. Objective: The aim of this study was to investigate

  12. Investigation of two-photon absorption induced excited state absorption in a fluorenyl-based chromophore.

    Science.gov (United States)

    Li, Changwei; Yang, Kun; Feng, Yan; Su, Xinyan; Yang, Junyi; Jin, Xiao; Shui, Min; Wang, Yuxiao; Zhang, Xueru; Song, Yinglin; Xu, Hongyao

    2009-12-03

    Two-photon absorption induced excited state absorption in the solution of a new fluorenyl-based chromophore is investigated by a time-resolved pump-probe technique using femtosecond pulses. With the help of an additional femtosecond open-aperture Z-scan technique, numerical simulations based on a three-energy level model are used to interpret the experimental results, and we determine the nonlinear optical parameters of this new chromophore uniquely. Large two-photon absorption cross section and excited state absorption cross section for singlet excited state are obtained, indicating a good candidate for optical limiting devices. Moreover, the influence of two-beam coupling induced energy transfer in neat N,N'-dimethylformamide solvent is also considered, although this effect is strongly restrained by the instantaneous two-photon absorption.

  13. Oral vitamin B12 replacement for the treatment of pernicious anaemia

    Directory of Open Access Journals (Sweden)

    Catherine Qiu Hua Chan

    2016-08-01

    Full Text Available Many patients with pernicious anaemia are treated with lifelong intramuscular vitamin B12 replacement. As early as the 1950s, there were studies suggesting that oral vitamin B12 replacement may provide adequate absorption. Nevertheless, oral vitamin B12 replacement in patients with pernicious anaemia remains uncommon in clinical practice. The objective of this review is to provide an update on the effectiveness of oral vitamin B12 for the treatment of pernicious anaemia, the recommended dosage and the required frequency of laboratory test and clinical monitoring. Relevant articles were identified by PubMed search from 1 January 1980 to 31 March 2016 and through hand search of relevant reference articles. Two randomised controlled trials, three prospective papers, one systematic review and three clinical reviews fulfilled our inclusion criteria. We found that oral vitamin B12 replacement at 1000mcg daily was adequate to replace vitamin B12 levels in patients with pernicious anaemia. We conclude that oral vitamin B12 is an effective alternative to vitamin B12 intramuscular injections. Patients should be offered this alternative after an informed discussion on the advantages and disadvantages of both treatment options.

  14. Oral Vitamin B12 Replacement for the Treatment of Pernicious Anemia.

    Science.gov (United States)

    Chan, Catherine Qiu Hua; Low, Lian Leng; Lee, Kheng Hock

    2016-01-01

    Many patients with pernicious anemia are treated with lifelong intramuscular (IM) vitamin B12 replacement. As early as the 1950s, there were studies suggesting that oral vitamin B12 replacement may provide adequate absorption. Nevertheless, oral vitamin B12 replacement in patients with pernicious anemia remains uncommon in clinical practice. The objective of this review is to provide an update on the effectiveness of oral vitamin B12 for the treatment of pernicious anemia, the recommended dosage, and the required frequency of laboratory test and clinical monitoring. Relevant articles were identified by PubMed search from January 1, 1980 to March 31, 2016 and through hand search of relevant reference articles. Two randomized controlled trials, three prospective papers, one systematic review, and three clinical reviews fulfilled our inclusion criteria. We found that oral vitamin B12 replacement at 1000 μg daily was adequate to replace vitamin B12 levels in patients with pernicious anemia. We conclude that oral vitamin B12 is an effective alternative to vitamin B12 IM injections. Patients should be offered this alternative after an informed discussion on the advantages and disadvantages of both treatment options.

  15. Diarrhea and novel dietary factors emerge as predictors of serum vitamin B12 in Panamanian children.

    Science.gov (United States)

    Scatliff, Candice E; Koski, Kristine G; Scott, Marilyn E

    2011-03-01

    The role of gastrointestinal infection as a factor determining vitamin B12 status in populations with low intake of animal-source foods is unclear. To determine dietary adequacy and serum concentrations of vitamin B12 in an extremely impoverished indigenous population of Panamanian children aged 12 to 60 months, and to identify predictors of both dietary and serum vitamin B12. A previous community-based survey provided the usual dietary intake and personal, household, and infection (Ascaris and diarrheal disease) information for 209 weaned children. Serum vitamin B12 was assayed using electrochemiluminescence for 65 of these children. Children with adequate or inadequate dietary vitamin B12 intake were compared, and predictors of dietary and serum vitamin B12 were identified using stepwise regression analyses of one index child per household. Dietary vitamin B12 intake was inadequate in 43% of children; these children were poorer, had less frequent diarrhea, and obtained a higher percentage of their energy from carbohydrate than children with adequate intake. Energy intake positively predicted dietary vitamin B12 intake. In contrast, serum vitamin B12 concentrations were normal in all but 3% of the children. Serum vitamin B12 was positively associated with weekly servings of fruit, corn-based food, and name (a traditional starchy food), but not with animal-source foods. Finally, serum vitamin B12 was not associated with Ascaris intensity but was lowered with increasing frequency of diarrhea. Although inadequate dietary intake of vitamin B12 was common, most serum values were normal. Nevertheless, diarrheal disease emerged as a negative predictor of serum vitamin B12 concentration.

  16. Elucidation of roles for vitamin B12 in regulation of folate, ubiquinone, and methionine metabolism.

    Science.gov (United States)

    Romine, Margaret F; Rodionov, Dmitry A; Maezato, Yukari; Anderson, Lindsey N; Nandhikonda, Premchendar; Rodionova, Irina A; Carre, Alexandre; Li, Xiaoqing; Xu, Chengdong; Clauss, Therese R W; Kim, Young-Mo; Metz, Thomas O; Wright, Aaron T

    2017-02-14

    Only a small fraction of vitamin B12-requiring organisms are able to synthesize B12 de novo, making it a common commodity in microbial communities. Initially recognized as an enzyme cofactor of a few enzymes, recent studies have revealed additional B12-binding enzymes and regulatory roles for B12 Here we report the development and use of a B12-based chemical probe to identify B12-binding proteins in a nonphototrophic B12-producing bacterium. Two unexpected discoveries resulted from this study. First, we identified a light-sensing B12-binding transcriptional regulator and demonstrated that it controls folate and ubiquinone biosynthesis. Second, our probe captured proteins involved in folate, methionine, and ubiquinone metabolism, suggesting that it may play a role as an allosteric effector of these processes. These metabolic processes produce precursors for synthesis of DNA, RNA, and protein. Thereby, B12 likely modulates growth, and by limiting its availability to auxotrophs, B12-producing organisms may facilitate coordination of community metabolism.

  17. Elucidation of roles for vitamin B12 in regulation of folate, ubiquinone, and methionine metabolism

    Science.gov (United States)

    Romine, Margaret F.; Rodionov, Dmitry A.; Maezato, Yukari; Anderson, Lindsey N.; Nandhikonda, Premchendar; Rodionova, Irina A.; Carre, Alexandre; Li, Xiaoqing; Xu, Chengdong; Clauss, Therese R. W.; Metz, Thomas O.; Wright, Aaron T.

    2017-01-01

    Only a small fraction of vitamin B12-requiring organisms are able to synthesize B12 de novo, making it a common commodity in microbial communities. Initially recognized as an enzyme cofactor of a few enzymes, recent studies have revealed additional B12-binding enzymes and regulatory roles for B12. Here we report the development and use of a B12-based chemical probe to identify B12-binding proteins in a nonphototrophic B12-producing bacterium. Two unexpected discoveries resulted from this study. First, we identified a light-sensing B12-binding transcriptional regulator and demonstrated that it controls folate and ubiquinone biosynthesis. Second, our probe captured proteins involved in folate, methionine, and ubiquinone metabolism, suggesting that it may play a role as an allosteric effector of these processes. These metabolic processes produce precursors for synthesis of DNA, RNA, and protein. Thereby, B12 likely modulates growth, and by limiting its availability to auxotrophs, B12-producing organisms may facilitate coordination of community metabolism. PMID:28137868

  18. Enhancing the vitamin B12 production and growth of Propionibacterium freudenreichii in tofu wastewater via a light-induced vitamin B12 riboswitch.

    Science.gov (United States)

    Yu, Yue; Zhu, Xuan; Shen, Yubiao; Yao, Huanghong; Wang, Peiheng; Ye, Kun; Wang, Xiaofeng; Gu, Qing

    2015-12-01

    The vitamin B12-dependent riboswitch is a crucial factor that regulates gene transcription to mediate the growth of and vitamin B12 synthesis by Propionibacterium freudenreichii. In this study, the effect of various wavelengths of light on the growth rate and vitamin B12 synthesis was studied. Red, green, and blue light-emitting diodes (LEDs) were selected, and a dark condition was used as the control. The microorganism growth rate was measured using a spectrophotometer and plate counting, while the vitamin B12 content was determined using an HPLC-based method. The optical density at 600 nm (OD600) values indicated that P. freudenreichii grew better under the continuous and discontinuous blue light conditions. Moreover, under the blue light condition, P. freudenreichii tended to have a higher growth rate (0.332 h(-1)) and vitamin B12 synthesis (ca. 10 μg/mL) in tofu wastewater than in dark conditions. HPLC analysis also showed that more methylcobalamin was produced under the blue light conditions than in the other conditions. The cbiB gene transcription results showed that blue light induced the synthesis of this vitamin B12 synthesis enzyme. Moreover, the results of inhibiting the expression of green fluorescent protein indicated that blue light removed the inhibition by the vitamin B12-dependent riboswitch. This method can be used to reduce fermentation time and produce more vitamin B12 in tofu wastewater.

  19. Obsessive compulsive disorder as early manifestation of b12 deficiency

    Directory of Open Access Journals (Sweden)

    Maryam Valizadeh

    2011-01-01

    Full Text Available B12 acts as a cofactor in synthesis of neurotransmitters such as serotonin and dopamine, thus B12 deficiency affects mood, emotions and sleeping and can lead to psychiatric disorders. Psychiatric manifestations of B12 deficiency are varied. They seldom precede anemia. We want to present a case of B12 deficiency which was presented with obsessive compulsive disorder.

  20. Transfer path based tyre absorption tests

    NARCIS (Netherlands)

    Tijs, E.; Makwana, B.K.; Peksel, O.; Amarnath, S.K.P.; Bekke, D.A.; Krishnan, K.S.

    2013-01-01

    The development process of a tyre usually involves a combination of simulation and testing techniques focused on characterizing acoustic/aerodynamic and vibrational phenomena. One of the acoustic phenomenon of interest is the absorption of the tyre, which affects the sound radiated. This properties

  1. Cognitive impairment and vitamin B12: a review.

    Science.gov (United States)

    Moore, Eileen; Mander, Alastair; Ames, David; Carne, Ross; Sanders, Kerrie; Watters, David

    2012-04-01

    This review examines the associations between low vitamin B12 levels, neurodegenerative disease, and cognitive impairment. The potential impact of comorbidities and medications associated with vitamin B12 derangements were also investigated. In addition, we reviewed the evidence as to whether vitamin B12 therapy is efficacious for cognitive impairment and dementia. A systematic literature search identified 43 studies investigating the association of vitamin B12 and cognitive impairment or dementia. Seventeen studies reported on the efficacy of vitamin B12 therapy for these conditions. Vitamin B12 levels in the subclinical low-normal range (vitamin B12 levels and may independently increase the risk for cognitive impairment. Vitamin B12 deficiency (Vitamin B12 supplements administered orally or parenterally at high dose (1 mg daily) were effective in correcting biochemical deficiency, but improved cognition only in patients with pre-existing vitamin B12 deficiency (serum vitamin B12 levels 19.9 μmol/L). Low serum vitamin B12 levels are associated with neurodegenerative disease and cognitive impairment. There is a small subset of dementias that are reversible with vitamin B12 therapy and this treatment is inexpensive and safe. Vitamin B12 therapy does not improve cognition in patients without pre-existing deficiency. There is a need for large, well-resourced clinical trials to close the gaps in our current understanding of the nature of the associations of vitamin B12 insufficiency and neurodegenerative disease.

  2. Measurements of vitamin B12 in human blood serum using resonance Raman spectroscopy

    Science.gov (United States)

    Tsiminis, G.; Schartner, E. P.; Brooks, J. L.; Hutchinson, M. R.

    2016-12-01

    Vitamin B12 (cobalamin and its derivatives) deficiency has been identified as a potential modifiable risk factor for dementia and Alzheimer's disease. Chronic deficiency of vitamin B12 has been significantly associated with an increased risk of cognitive decline. An effective and efficient method for measuring vitamin B12 concentration in human blood would enable ongoing tracking and assessment of this potential modifiable risk factor. In this work we present an optical sensor based on resonance Raman spectroscopy for rapid measurements of vitamin B12 in human blood serum. The measurement takes less than a minute and requires minimum preparation (centrifuging) of the collected blood samples.

  3. TD-DFT Insight into Photodissociation of Co-C Bond in Coenzyme B12

    Science.gov (United States)

    Kozlowski, Pawel; Liu, Hui; Kornobis, Karina; Lodowski, Piotr; Jaworska, Maria

    2013-12-01

    Coenzyme B12 (AdoCbl) is one of the most biologically active forms of vitamin B12, and continues to be a topic of active research interest. The mechanism of Co-C bond cleavage in AdoCbl, and the corresponding enzymatic reactions are however, not well understood at the molecular level. In this work, time-dependent density functional theory (TD-DFT) has been applied to investigate the photodissociation of coenzyme B12. To reduce computational cost, while retaining the major spectroscopic features of AdoCbl, a truncated model based on ribosylcobalamin (RibCbl) was used to simulate Co-C photodissociation. Equilibrium geometries of RibCbl were obtained by optimization at the DFT/BP86/TZVP level of theory, and low-lying excited states were calculated by TD-DFT using the same functional and basis set. The calculated singlet states, and absorption spectra were simulated in both the gas phase, and water, using the polarizable continuum model (PCM). Both spectra were in reasonable agreement with experimental data, and potential energy curves based on vertical excitations were plotted to explore the nature of Co-C bond dissociation. It was found that a repulsive 3(σCo-C → σ*Co-C) triplet state became dissociative at large Co-C bond distance, similar to a previous observation for methylcobalamin (MeCbl). Furthermore, potential energy surfaces (PESs) obtained as a function of both Co-CRib and Co-NIm distances, identify the S1 state as a key intermediate generated during photoexcitation of RibCbl, attributed to a mixture of a MLCT (metal-to-ligand charge transfer) and a σ bonding-ligand charge transfer (SBLCT) states.

  4. Hypervitaminosis B12 in maintenance hemodialysis patients receiving massive supplementation of vitamin B12.

    Science.gov (United States)

    Mangiarotti, G; Canavese, C; Salomone, M; Thea, A; Pacitti, A; Gaido, M; Calitri, V; Pelizza, D; Canavero, W; Vercellone, A

    1986-11-01

    We have administered routinely a multivitamin preparation containing a megadose of B12 to 106 hemodialysis patients after dialysis treatments. We found that these patients had very high levels of serum vitamin B12 which returned to original values only after a period of three years after stopping the vitamin. Discontinuing therapy had no effect on hemoglobin, mean erythrocyte corpuscular volume, or motor nerve conduction velocity. It is not known whether maintaining a prolonged high level of vitamin B12 is harmful. However, animal and epidemiologic studies have suggested that both cobalamin and cobalt may be potentially toxic. In view of the absence of demonstrable benefit and the possible risk of toxicity, we believe that the use of such megadose vitamin compounds in dialysis patients should be re-evaluated.

  5. [Maternal Crohn's disease-related vitamin B12 deficient megaloblastic anemia in an infant].

    Science.gov (United States)

    Ohyama, Wataru; Yamaoka, Masayoshi; Yokoi, Kentaro; Iwahashi, Megumi; Inage, Yuka; Arihiro, Seiji; Koganei, Kazutaka; Sugita, Akira; Ida, Hiroyuki; Akiyama, Masaharu

    2016-01-01

    We report an 11-month-old breast-fed boy with feeding difficulties, lethargy, and developmental delay. Blood examination showed pancytopenia and decreased serum levels of vitamin B12. Anisocytosis and poikilocytes were detected in his peripheral blood, and increased megaloblastosis without leukemic cells was detected in his bone marrow. After the diagnosis of megaloblastic anemia due to vitamin B12 deficiency, symptoms were improved by vitamin B12 administration. Further investigation of the mother identified Crohn's disease and suggested that the supply of vitamin B12 from the mother to the infant, via the placenta during pregnancy and via breast milk after birth, was decreased due to impaired absorption of vitamin B12 in the mother's small intestine. Magnetic resonance imaging of the boy's brain on admission showed cerebral cortex atrophy which had improved by the age of 1 year and 10 months after vitamin B12 treatment, though developmental delay was still evident at the age of 3 years. Infantile vitamin B12 deficiency often presents with nonspecific manifestations, such as developmental delay and failure to thrive, in addition to anemia and is thus not easily diagnosed. To prevent severe neurological sequelae, this condition must be rapidly diagnosed, because a prolonged duration increases the risk of permanent disabilities.

  6. Status of Vitamin B12 and Folate among the Urban Adult Population in South India.

    Science.gov (United States)

    Sivaprasad, M; Shalini, T; Balakrishna, N; Sudarshan, M; Lopamudra, P; Suryanarayana, P; Arlappa, N; Ravikumar, B P; Radhika, M S; Reddy, G Bhanuprakash

    2016-01-01

    Deficiency of vitamin B12 (B12) and folate (FA) leads to a wide spectrum of disorders that affect all age groups. However, reports on B12 and FA status in healthy adults in India are limited. Hence, we determined the plasma levels and dietary intake of B12 and FA in the adult population. We conducted a community-based cross-sectional study in an urban setup among 630 apparently healthy adults distributed into 3 age groups: 21-40, 41-60 and >60 years. Plasma concentrations of B12 and FA were analyzed by radio immunoassay and dietary intake by 24-hour recall method. The overall prevalence of FA deficiency was 12%, but there was no significant difference in plasma FA concentrations among the groups. While the overall prevalence of B12 deficiency was 35%, it was significantly higher in the 21-40 (44%) and 41-60 age groups (40%) when compared with the >60 group (30%). B12 deficiency was higher in vegetarians (54%) compared to those consuming mixed diet (31%), and the reverse was the case with FA. However, the dietary intakes of FA and B12 were not significantly different among the groups. These results indicate a higher prevalence of B12 deficiency in apparently healthy adults in an urban setup. © 2015 S. Karger AG, Basel.

  7. Involuntary movement in infants during vitamin B12 treatment

    Directory of Open Access Journals (Sweden)

    Ayşe Tosun

    2011-12-01

    Full Text Available Megaloblastic anemia is rare in infants and is generally due to vitamin B12 (cobalamin deficiency in the mother. Neurologic symptoms of vitamin B12 deficiency include irritability, failure to thrive, hypotonia, and developmental regression/delay. Herein we present 2 infants with vitamin B12 that developed movement disorder 5 d after initiation of vitamin B12 treatment. Symptoms included tremor and myoclonus, involving in particular the face, tongue, and hands. Clinical findings in infants associated with vitamin B12 deficiency vary, and temporary involuntary movement can be observed during vitamin B12 therapy.

  8. Vitamin B12 intake and status and cognitive function in elderly people

    NARCIS (Netherlands)

    Doets, E.L.; Wijngaarden, van J.P.; Szczecinska, A.; Dullemeijer, C.; Souverein, O.W.; Dhonukshe-Rutten, R.A.M.; Cavelaars, A.J.E.M.; Veer, van 't P.; Brzozowska, A.M.; Groot, de C.P.G.M.

    2013-01-01

    Current recommendations on vitamin B12 intake vary from 1.4 to 3.0 µg per day and are based on the amount needed for maintenance of hematologic status or on the amount needed to compensate obligatory losses. This systematic review evaluates whether the relation between vitamin B12 intake and

  9. Vitamin B12 intake and status and cognitive function in elderly people

    NARCIS (Netherlands)

    Doets, E.L.; Wijngaarden, van J.P.; Szczecinska, A.; Dullemeijer, C.; Souverein, O.W.; Dhonukshe-Rutten, R.A.M.; Cavelaars, A.J.E.M.; Veer, van 't P.; Brzozowska, A.M.; Groot, de C.P.G.M.

    2013-01-01

    Current recommendations on vitamin B12 intake vary from 1.4 to 3.0 µg per day and are based on the amount needed for maintenance of hematologic status or on the amount needed to compensate obligatory losses. This systematic review evaluates whether the relation between vitamin B12 intake and cogniti

  10. Vitamin B12-responsive neuropathies: A case series.

    Science.gov (United States)

    Solomon, Lawrence R

    2016-05-01

    Neuropathies often accompany vitamin B12 deficiency. Since many neuropathies are linked to oxidative stress and since B12 has both antioxidant and neurotrophic properties, B12 may also be effective treatment in non-deficient subjects. Thus, the characteristics and predictors of B12-responsive neuropathies and their relationship to disorders associated with increased oxidative stress (oxidant risks) were examined. Retrospective review of 78 subjects with neurological abnormalities treated with B12 and evaluated by the measurement of B12 and the B12-dependent metabolites, methylmalonic acid (MMA), and homocysteine. Sixty-five subjects had neurological improvement (83%), including 35 with other known causes of neuropathy. Only two responders had B12-responsive macrocytosis. Pretherapy B12, MMA, and homocysteine values were normal in 72, 33 and 54% of responders, with all three normal in 23%. Moreover, B12 therapy did not significantly decrease elevated MMA and homocysteine levels in 20 and 37%, respectively, of responders tested but did decrease both metabolites in 75% of evaluable non-responders. At least one oxidant risk was present in 41 of the 46 responders with normal B12 levels (89%). Oral therapy was effective, but parenteral B12 improved responses in four subjects. B12-responsive neuropathies are thus (1) common even when confounding disorders are present; (2) dissociated from the presence of hematological abnormalities; (3) dissociated from the presence of B12-responsive metabolical abnormalities; and (4) associated with the presence of oxidant risks when B12 levels are normal. Since no predictors of responses to B12 therapy were identified, empiric trials with parenteral B12 should be considered in appropriate subjects.

  11. Radiolysis of cyanocobalamin (vitamin B 12)

    Science.gov (United States)

    Juanchi, X.; Albarran, G.; Negron-Mendoza, A.

    2000-03-01

    Research on the radiolysis of vitamins is of considerable interest since these compounds are important nutritional constituents in foods and in dietetic supplements. In spite of these considerations there are few data and very often difficult to compare for the radiolytic behavior of vitamins. In this work we focused our attention on to the study of the radiolysis of cyanocobalamin (vitamin B 12) in solid state and in aqueous solutions. The procedure was followed by HPLC and UV-spectroscopy. The results obtained in aqueous solutions showed a dependence of the decomposition as a linear function of the dose. The G of decomposition for a 1×10 -5 M solution was 3.3. In the solid state the vitamin was very stable towards the irradiation in the conditions used in this study with a G=2.1×10 -3. A study made with Serratia marcescens as a microbiological contaminant showed that at the sterilization dose there is a destruction of the vitamin in aqueous solution. In the solid state the degree of decomposition was 7%.

  12. Recurrent seizures: An unusual manifestation of vitamin B12 deficiency

    Directory of Open Access Journals (Sweden)

    Kumar S

    2004-01-01

    Full Text Available The present report highlights an unusual presentation of vitamin B12 deficiency— recurrent seizures in a 26-year-old man. His symptoms responded to parenteral vitamin B12 therapy. The relevant literature is reviewed.

  13. Intakes of Folate and Vitamin B12 and Biomarkers of Status in the Very Old: The Newcastle 85+ Study

    Science.gov (United States)

    Mendonça, Nuno; Mathers, John C.; Adamson, Ashley J.; Martin-Ruiz, Carmen; Seal, Chris J.; Jagger, Carol; Hill, Tom R.

    2016-01-01

    Very old adults are at increased risk of folate and vitamin B12 deficiencies due to reduced food intake and gastrointestinal absorption. The main aim was to determine the association between folate and vitamin B12 intake from total diets and food groups, and status. Folate or vitamin B12 intakes (2 × 24 h multiple pass recalls) and red blood cell (RBC) folate or plasma vitamin B12 (chemiluminescence immunoassays) concentrations were available at baseline for 731 participants aged 85 from the Newcastle 85+ Study (North-East England). Generalized additive and binary logistic models estimated the associations between folate and vitamin B12 intakes from total diets and food groups, and RBC folate and plasma B12. Folate intake from total diets and cereal and cereal products was strongly associated with RBC folate (p < 0.001). Total vitamin B12 intake was weakly associated with plasma vitamin B12 (p = 0.054) but those with higher intakes from total diets or meat and meat products were less likely to have deficient status. Women homozygous for the FUT2 G allele had higher concentrations of plasma vitamin B12. Cereals and cereal products are a very important source of folate in the very old. Higher intakes of folate and vitamin B12 lower the risk of “inadequate” status. PMID:27690091

  14. Intakes of Folate and Vitamin B12 and Biomarkers of Status in the Very Old: The Newcastle 85+ Study.

    Science.gov (United States)

    Mendonça, Nuno; Mathers, John C; Adamson, Ashley J; Martin-Ruiz, Carmen; Seal, Chris J; Jagger, Carol; Hill, Tom R

    2016-09-28

    Very old adults are at increased risk of folate and vitamin B12 deficiencies due to reduced food intake and gastrointestinal absorption. The main aim was to determine the association between folate and vitamin B12 intake from total diets and food groups, and status. Folate or vitamin B12 intakes (2 × 24 h multiple pass recalls) and red blood cell (RBC) folate or plasma vitamin B12 (chemiluminescence immunoassays) concentrations were available at baseline for 731 participants aged 85 from the Newcastle 85+ Study (North-East England). Generalized additive and binary logistic models estimated the associations between folate and vitamin B12 intakes from total diets and food groups, and RBC folate and plasma B12. Folate intake from total diets and cereal and cereal products was strongly associated with RBC folate (p B12 intake was weakly associated with plasma vitamin B12 (p = 0.054) but those with higher intakes from total diets or meat and meat products were less likely to have deficient status. Women homozygous for the FUT2 G allele had higher concentrations of plasma vitamin B12. Cereals and cereal products are a very important source of folate in the very old. Higher intakes of folate and vitamin B12 lower the risk of "inadequate" status.

  15. 21 CFR 184.1945 - Vitamin B12.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Vitamin B12. 184.1945 Section 184.1945 Food and... Substances Affirmed as GRAS § 184.1945 Vitamin B12. (a) Vitamin B12, also known as cyanocobalamin (C63H88Co... is used in food at levels not to exceed current good manufacturing practice. Vitamin B12 also may...

  16. 你缺少维生素B12

    Institute of Scientific and Technical Information of China (English)

    贺佩祥

    2007-01-01

    @@ 身体如何获得维生素B12 机体需要靠以下几个环节来获得足够的维生素B12: 1.食物在胃酸的作用下释放出维生素B12 2.维生素B12与一种称为"内因子"的物质结合

  17. 21 CFR 862.1810 - Vitamin B12 test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Vitamin B12 test system. 862.1810 Section 862.1810 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED....1810 Vitamin B12 test system. (a) Identification. A vitamin B12 test system is a device intended to...

  18. 21 CFR 582.5945 - Vitamin B12.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Vitamin B12. 582.5945 Section 582.5945 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5945 Vitamin B12. (a) Product. Vitamin B12. (b) Conditions of use. This substance...

  19. Selective Malabsorption of Vitamin B12 and Vitamin B12-Intrinsic Factor With Megaloblastic Anemia in an Adult

    Science.gov (United States)

    Chisholm, Joseph C.

    1985-01-01

    The first case of megaloblastic anemia due to selective malabsorption of vitamin B12 and vitamin B12-intrinsic factor is described in an otherwise normal female adult, in whom pernicious anemia had previously been diagnosed. PMID:4057272

  20. Organometallic B12-DNA conjugate: synthesis, structure analysis, and studies of binding to human B12-transporter proteins.

    Science.gov (United States)

    Hunger, Miriam; Mutti, Elena; Rieder, Alexander; Enders, Barbara; Nexo, Ebba; Kräutler, Bernhard

    2014-10-06

    Design, synthesis, and structural characterization of a B12-octadecanucleotide are presented herein, a new organometallic B12-DNA conjugate. In such covalent conjugates, the natural B12 moiety may be a versatile vector for controlled in vivo delivery of oligonucleotides to cellular targets in humans and animals, through the endogenous B12 transport systems. Binding of the organometallic B12 octadecanucleotide to the three important human proteins of B12 transport was studied, to examine its structural suitability for the task of eventual in vivo oligonucleotide delivery. Binding was efficient with transcobalamin (TC), but not so efficient with the homologous glycoproteins intrinsic factor and haptocorrin. Binding of the B12 octadecanucleotide to TC suggests the capacity of the B12 moiety to serve as a natural vector for specific transport of single stranded, organometallic oligonucleotide loads from the blood stream into cells.

  1. Imerslund-Gräsbeck syndrome (selective vitamin B12 malabsorption with proteinuria

    Directory of Open Access Journals (Sweden)

    Gräsbeck Ralph

    2006-05-01

    Full Text Available Abstract Imerslund-Gräsbeck syndrome (IGS or selective vitamin B12 (cobalamin malabsorption with proteinuria is a rare autosomal recessive disorder characterized by vitamin B12 deficiency commonly resulting in megaloblastic anemia, which is responsive to parenteral vitamin B12 therapy and appears in childhood. Other manifestations include failure to thrive and grow, infections and neurological damage. Mild proteinuria (with no signs of kidney disease is present in about half of the patients. Anatomical anomalies in the urinary tract were observed in some Norwegian patients. Vitamin B12 absorption tests show low absorption, not corrected by administration of intrinsic factor. The symptoms appear from 4 months (not immediately after birth as in transcobalamin deficiency up to several years after birth. The syndrome was first described in Finland and Norway where the prevalence is about 1:200,000. The cause is a defect in the receptor of the vitamin B12-intrinsic factor complex of the ileal enterocyte. In most cases, the molecular basis of the selective malabsorption and proteinuria involves a mutation in one of two genes, cubilin (CUBN on chromosome 10 or amnionless (AMN on chromosome 14. Both proteins are components of the intestinal receptor for the vitamin B12-intrinsic factor complex and the receptor mediating the tubular reabsorption of protein from the primary urine. Management includes life-long vitamin B12 injections, and with this regimen, the patients stay healthy for decades. However, the proteinuria persists. In diagnosing this disease, it is important to be aware that cobalamin deficiency affects enterocyte function; therefore, all tests suggesting general and cobalamin malabsorption should be repeated after abolishment of the deficiency.

  2. Neuro-regression in vitamin B12 deficiency.

    Science.gov (United States)

    Agrawal, Sanwar; Nathani, Shweta

    2009-01-01

    Neuroregression in infants has varied aetiology and vitamin B12 deficiency is one of the uncommon causes. Infantile vitamin B12 deficiency is encountered in malnourished infants or in offspring of strict vegan mothers. We present two cases, both infants of 10 and 8 months of age, whose mothers had vitamin B12 deficiency. On admission, the patients were apathic, hypotonic and lethargic. Serum vitamin B12 levels were below normal limits. On cranial MRI, T2-weighted images revealed frontoparietal cortical atrophy. Both the infants responded to vitamin B12 treatment.

  3. [Simulation of TDLAS direct absorption based on HITRAN database].

    Science.gov (United States)

    Qi, Ru-birn; He, Shu-kai; Li, Xin-tian; Wang, Xian-zhong

    2015-01-01

    Simulating of the direct absorption TDLAS spectrum can help to comprehend the process of the absorbing and understand the influence on the absorption signal with each physical parameter. Firstly, the basic theory and algorithm of direct absorption TDLAS is studied and analyzed thoroughly, through giving the expressions and calculating steps of parameters based on Lambert-Beer's law, such as line intensity, absorption cross sections, concentration, line shape and gas total partition functions. The process of direct absorption TDLAS is simulated using MATLAB programs based on HITRAN spectra database, with which the absorptions under a certain temperature, pressure, concentration and other conditions were calculated, Water vapor is selected as the target gas, the absorptions of which under every line shapes were simulated. The results were compared with that of the commercial simulation software, Hitran-PC, which showed that, the deviation under Lorentz line shape is less than 0. 5%, and that under Gauss line shape is less than 2. 5%, while under Voigt line shape it is less than 1%. It verified that the algorithm and results of this work are correct and accurate. The absorption of H2O in v2 + v3 band under different pressure and temperature is also simulated. In low pressure range, the Doppler broadening dominant, so the line width changes little with varied.pressure, while the line peak increases with rising pressure. In high pressure range, the collision broadening dominant, so the line width changes wider with increasing pressure, while the line peak approaches to a constant value with rising pressure. And finally, the temperature correction curve in atmosphere detection is also given. The results of this work offer the reference and instruction for the application of TDLAS direct absorption.

  4. Experimental vitamin B12 deficiency in a human subject: a longitudinal investigation of the performance of the holotranscobalamin (HoloTC, Active-B12) immunoassay.

    Science.gov (United States)

    Golding, Paul Henry

    2016-01-01

    Based on Victor Herbert's model for sequential stages in the development of vitamin B12 deficiency, the holotranscobalamin (HoloTC) immunoassay has controversially been promoted as a more specific and sensitive replacement for the total vitamin B12 test, for the diagnosis of deficiency. There have been no longitudinal studies, by means of experimental cobalamin deficiency, because ethical considerations prevent such risky studies on patients or healthy human volunteers. The objective was to provide a detailed record of the response of HoloTC, compared to total vitamin B12 and metabolites, to the development of experimental vitamin B12 deficiency in an initially replete human subject. This 54 year old male, with a vitamin B12 deficiency possibly caused by a defect in the intracellular cobalamin metabolism, ensured an initially replete condition by means of oral doses of cyanocobalamin supplements at 1000 μg/day for 12 weeks. The subject then depleted himself of vitamin B12, by withholding treatment and using a low-cobalamin diet, until significant metabolic disturbances were observed. The responses of serum total vitamin B12 and HoloTC and the two metabolites, plasma methylmalonic acid and homocysteine, were monitored by weekly blood tests. HoloTC was not significantly more sensitive than either total serum vitamin B12 or total homocysteine, and was much less sensitive than methylmalonic acid. HoloTC decreased from an initial concentration of >128 pmol/L to a minimum of 33 pmol/L on day 742, the only day on which it fell below the lower limit of the reference interval. Total vitamin B12 decreased from an initial concentration of 606 pmol/L to a minimum of 171 pmol/L on day 728. Total homocysteine increased from an initial concentration of 8.4 μmol/L to a maximum of 14.2 μmol/L on day 609. Methylmalonic acid unexpectedly contained four distinct peaks; initially at 0.17 μmol/L, it first exceeded the upper limit of the reference interval on day 386

  5. The Folate-Vitamin B12 Interaction, Low Hemoglobin, and the Mortality Risk from Alzheimer's Disease.

    Science.gov (United States)

    Min, Jin-Young; Min, Kyoung-Bok

    2016-03-21

    Abnormal hemoglobin levels are a risk factor for Alzheimer's disease (AD). Although the mechanism underlying these associations is elusive, inadequate micronutrients, particularly folate and vitamin B12, may increase the risk for anemia, cognitive impairment, and AD. In this study, we investigated whether the nutritional status of folate and vitamin B12 is involved in the association between low hemoglobin levels and the risk of AD mortality. Data were obtained from the 1999-2006 National Health and Nutrition Examination Survey (NHANES) and the NHANES (1999-2006) Linked Mortality File. A total of 4,688 participants aged ≥60 years with available baseline data were included in this study. We categorized three groups based on the quartiles of folate and vitamin B12 as follows: Group I (low folate and vitamin B12); Group II (high folate and low vitamin B12 or low folate and high vitamin B12); and Group III (high folate and vitamin B12). Of 4,688 participants, 49 subjects died due to AD. After adjusting for age, sex, ethnicity, education, smoking history, body mass index, the presence of diabetes or hypertension, and dietary intake of iron, significant increases in the AD mortality were observed in Quartile1 for hemoglobin (HR: 8.4, 95% CI: 1.4-50.8), and the overall risk of AD mortality was significantly reduced with increases in the quartile of hemoglobin (p for trend = 0.0200), in subjects with low levels of both folate and vitamin B12 at baseline. This association did not exist in subjects with at least one high level of folate and vitamin B12. Our finding shows the relationship between folate and vitamin B12 levels with respect to the association between hemoglobin levels and AD mortality.

  6. Vitamin B12 Deficiency in Relation to Functional Disabilities

    Directory of Open Access Journals (Sweden)

    Heather E. Rasmussen

    2013-11-01

    Full Text Available This study was designed to assess whether symptoms, functional measures, and reported disabilities were associated with vitamin B12 (B12 deficiency when defined in three ways. Participants, aged 60 or more years of age, in 1999–2002 National Health and Nutrition Examination Surveys (NHANES were categorized in relation to three previously used definitions of B12 deficiency: (1 serum B12 20 μmol/L; and (3 serum B12 0.21 μmol/L. Functional measures of peripheral neuropathy, balance, cognitive function, gait speed, along with self-reported disability (including activities of daily living were examined with standardized instruments by trained NHANES interviewers and technicians. Individuals identified as B12 deficient by definition 2 were more likely to manifest peripheral neuropathy OR (odds (95% confidence intervals, p value: 9.70 (2.24, 42.07, 0.004 and report greater total disability, 19.61 (6.22, 61.86 0.0001 after adjustments for age, sex, race, serum creatinine, and ferritin concentrations, smoking, diabetes, and peripheral artery disease. Smaller, but significantly increased, odds of peripheral neuropathy and total disability were also observed when definition 3 was applied. Functional measures and reported disabilities were associated with B12 deficiency definitions that include B12 biomarkers (homocysteine or methylmalonic acid. Further study of these definitions is needed to alert clinicians of possible subclinical B12 deficiency because functional decline amongst older adults may be correctable if the individual is B12 replete.

  7. The impact of vegan diet on B-12 status in healthy omnivores: five-year prospective study

    Directory of Open Access Journals (Sweden)

    Edyta Mądry

    2012-06-01

    Full Text Available Background. There are no long-term prospective studies assessing the impact of the vegan diet on vitamin B-12 (B-12 status. Many vegans take B-12 supplements irregularly or refuse to adopt them at all, considering them to be “unnatural” products. The use of B-12 fortifi ed food may be an alternative. Therefore, we aimed to estimate the long-term effect of a vegan diet on serum B-12 concentrations in healthy omnivore adults, comparing the infl uence of natural products consumption and B-12 fortifi ed food. Material and methods. A fi ve year prospective study was carried out comprising 20 omnivore healthy adult subjects, who moved to strict vegan diet for 5 years. Ten volunteers followed vegan diet based entirely on natural products, while the remaining ten subjects consumed food fortifi ed in B-12. In all subjects serum vitamin B-12 concentration was determined before and 6, 12, 24 and 60 months after the implementation of the diet. Results. A signifi cant decrease (p < 0.0002 of serum B-12 concentrations in the whole studied group was noted after 60 months of vegan diet. However, observed changes were in fact limited to the subgroup consuming exclusively natural products (p < 0.0001. Conclusions. Transition from omnivore to vegan diet is associated with the risk of vitamin B-12 defi ciency. B-12 fortifi ed products might constitute a valuable alternative in vegans refusing to take vitamin supplements.

  8. Genetic determinants of serum vitamin B12 and their relation to body mass index.

    Science.gov (United States)

    Allin, Kristine H; Friedrich, Nele; Pietzner, Maik; Grarup, Niels; Thuesen, Betina H; Linneberg, Allan; Pisinger, Charlotta; Hansen, Torben; Pedersen, Oluf; Sandholt, Camilla H

    2016-12-19

    Lower serum vitamin B12 levels have been related to adverse metabolic health profiles, including adiposity. We used a Mendelian randomization design to test whether this relation might be causal. We included two Danish population-based studies (ntotal = 9311). Linear regression was used to test for associations between (1) serum vitamin B12 levels and body mass index (BMI), (2) genetic variants and serum vitamin B12 levels, and (3) genetic variants and BMI. The effect of a genetically determined decrease in serum vitamin B12 on BMI was estimated by instrumental variable regression. Decreased serum vitamin B12 associated with increased BMI (P B12 associated variants associated strongly with serum vitamin B12 (P B12 was associated with a 0.09 kg/m(2) (95% CI 0.05; 0.13) increase in BMI (P = 3 × 10(-5)), whereas a genetically induced 20% decrease in serum vitamin B12 had no effect on BMI [-0.03 (95% CI -0.22; 0.16) kg/m(2)] (P = 0.74). Nevertheless, the strongest serum vitamin B12 variant, FUT2 rs602662, which was excluded from the B12 genetic risk score due to potential pleiotropic effects, showed a per allele effect of 0.15 kg/m(2) (95% CI 0.01; 0.32) on BMI (P = 0.03). This association was accentuated including two German cohorts (ntotal = 5050), with a combined effect of 0.19 kg/m(2) (95% CI 0.08; 0.30) (P = 4 × 10(-4)). We found no support for a causal role of decreased serum vitamin B12 levels in obesity. However, our study suggests that FUT2, through its regulation of the cross-talk between gut microbes and the human host, might explain a part of the observational association between serum vitamin B12 and BMI.

  9. New insights into erythropoiesis: the roles of folate, vitamin B12, and iron.

    Science.gov (United States)

    Koury, Mark J; Ponka, Prem

    2004-01-01

    Erythropoiesis is the process in which new erythrocytes are produced. These new erythrocytes replace the oldest erythrocytes (normally about one percent) that are phagocytosed and destroyed each day. Folate, vitamin B12, and iron have crucial roles in erythropoiesis. Erythroblasts require folate and vitamin B12 for proliferation during their differentiation. Deficiency of folate or vitamin B12 inhibits purine and thymidylate syntheses, impairs DNA synthesis, and causes erythroblast apoptosis, resulting in anemia from ineffective erythropoiesis. Erythroblasts require large amounts of iron for hemoglobin synthesis. Large amounts of iron are recycled daily with hemoglobin breakdown from destroyed old erythrocytes. Many recently identified proteins are involved in absorption, storage, and cellular export of nonheme iron and in erythroblast uptake and utilization of iron. Erythroblast heme levels regulate uptake of iron and globin synthesis such that iron deficiency causes anemia by retarded production rates with smaller, less hemoglobinized erythrocytes.

  10. Genetic determinants of serum vitamin B12 and their relation to body mass index

    DEFF Research Database (Denmark)

    Allin, Kristine H; Friedrich, Nele; Pietzner, Maik

    2017-01-01

    Lower serum vitamin B12 levels have been related to adverse metabolic health profiles, including adiposity. We used a Mendelian randomization design to test whether this relation might be causal. We included two Danish population-based studies (ntotal = 9311). Linear regression was used to test......(-4)). We found no support for a causal role of decreased serum vitamin B12 levels in obesity. However, our study suggests that FUT2, through its regulation of the cross-talk between gut microbes and the human host, might explain a part of the observational association between serum vitamin B12 and BMI....

  11. Temperature and pressure measurement based on tunable diode laser absorption spectroscopy with gas absorption linewidth detection

    Science.gov (United States)

    Meng, Yunxia; Liu, Tiegen; Liu, Kun; Jiang, Junfeng; Wang, Tao; Wang, Ranran

    2014-11-01

    A gas temperature and pressure measurement method based on Tunable Diode Laser Absorption Spectroscopy (TDLAS) detecting linewidth of gas absorption line was proposed in this paper. Combined with Lambert-Beer Law and ideal gas law, the relationship between temperature, pressure and gas linewidth with Lorentzian line shape was investigated in theory. Taking carbon monoxide (CO) at 1567.32 nm for example, the linewidths of gas absorption line in different temperatures and pressures were obtained by simulation. The relationship between the linewidth of second harmonic and temperature, pressure with the coefficient 0.025 pm/K and 0.0645 pm/kPa respectively. According to the relationship of simulation results and detected linewidth, the undefined temperature and pressure of CO gas were measured. The gas temperature and pressure measurement based on linewidth detection, avoiding the influence of laser intensity, is an effective temperature and pressure measurement method. This method also has the ability to detect temperature and pressure of other gases with Lorentzian line shape.

  12. Premarital screening of 466 Mediterranean women for serum ferritin, vitamin B12, and folate concentrations.

    Science.gov (United States)

    Karabulut, Aysun; Güler, Ömer Tolga; Karahan, Hatice Tuba; Özkan, Sevgi; Koyuncu, Hasan; Demirciler, Ibrahim

    2015-01-01

    Iron, folate, and vitamin B12 serum levels are closely related with dietary habits and have an essential role in the healthy development of a fetus. We aimed to investigate hemoglobin, ferritin, folate, and vitamin B12 levels in preconceptional women in an area where a plant-based diet referred to as Mediterranean cuisine is commonly used. The study population included 466 women between the ages of 18 and 45 years admitted for thalassemia screening. Sociodemographic variables and history of menometrorrhagia, pica, and dietary habits were collected. Serum vitamin B12, folate, ferritin, and hemoglobin levels were measured. Ferritin of <12µg/L, vitamin B12 of <200 pg/mL, and folate of <4 ng/mL were accepted as deficiencies. Hemoglobin level of <12 g/dL was classified as anemia. Polymenorrhea was present in 11.7% and hypermenorrhea in 24.8% of women. Anemia was detected in 24.9% and thalassemia trait in 3.0% of women. Low ferritin levels were observed in 46.1%, vitamin B12 in 21.6%, and folate in 3.4% of women. In the group with low vitamin B12, decreased meat consumption was more prevalent (27.5% vs. 16.9%; P = 0.019). Vitamin B12 and iron are the main micronutrients depleted in our community. This necessitates implementing a public health program for women consuming a Mediterranean diet.

  13. Spinal myoclonus associated with vitamin B12 deficiency.

    Science.gov (United States)

    Dogan, Ebru Apaydin; Yuruten, Betigul

    2007-11-01

    We report a 85-year-old female patient with involuntary and regular movements restricted to abdominal muscles, resembling belly dance, with additional clinical features; ataxia, impaired cognition, neuropathy and glossitis. We initially excluded the possible cortical and spinal structural abnormalities with magnetic resonance imagings and performed routine blood analysis which revealed that serum vitamin B12 (vB12) level was under normal ranges. The relation of low serum vB12 level and myoclonus is speculative and very few studies have demonstrated such patients. In this case report, serum vB12 deficiency is discussed in the context of its probable role in the generation of spinal myoclonus.

  14. Status of serum vitamin B12 and folate in patients with inflammatory bowel disease in China

    Science.gov (United States)

    Huang, Shaozhong; Ma, Jiayi; Zhu, Mingming

    2017-01-01

    Background/Aims Inflammatory bowel disease (IBD) primarily involves the intestinal tract and can affect vitamin absorption. This study was designed to assess the prevalence of vitamin B12 and folate deficiencies in patients with IBD, and to identify the risk factors associated with abnormal serum vitamin B12 and folate levels. Methods We evaluated the medical records of 195 patients with Crohn's disease (CD) and 62 patients with ulcerative colitis (UC), and selected 118 healthy subjects for the control group. Results There were more CD patients with vitamin B12 deficiency than UC patients (14.9% vs. 3.2%, P=0.014) and controls (14.9% vs. 4.2%, P=0.003). The prevalence of folate deficiency was higher in CD patients than in controls (13.3% vs. 3.4%, P=0.004). There were no significant differences in the serum vitamin B12 and folate statuses of the UC and control groups. Patients with prior ileal or ileocolic resection showed a higher prevalence of abnormal vitamin B12 levels than those without prior resection (n=6/16, n=23/179; P=0.018). A disease duration within 5 years was a risk factor of abnormal folate levels in CD patients. Conclusions This study showed that vitamin B12 and folate deficiencies were more common in patients with CD than in UC patients and controls. Prior ileal or ileocolonic resection was a risk factor of serum vitamin B12 abnormalities, and a disease duration within 5 years was a risk factor of low serum folate levels in CD patients. PMID:28239320

  15. Carnitine metabolism in the vitamin B-12-deficient rat.

    Science.gov (United States)

    Brass, E P; Stabler, S P

    1988-01-01

    In vitamin B-12 (cobalamin) deficiency the metabolism of propionyl-CoA and methylmalonyl-CoA are inhibited secondarily to decreased L-methylmalonyl-CoA mutase activity. Production of acylcarnitines provides a mechanism for removing acyl groups and liberating CoA under conditions of impaired acyl-CoA utilization. Carnitine metabolism was studied in the vitamin B-12-deficient rat to define the relationship between alterations in acylcarnitine generation and the development of methylmalonic aciduria. Urinary excretion of methylmalonic acid was increased 200-fold in vitamin B-12-deficient rats as compared with controls. Urinary acylcarnitine excretion was increased in the vitamin B-12-deficient animals by 70%. This increase in urinary acylcarnitine excretion correlated with the degree of metabolic impairment as measured by the urinary methylmalonic acid elimination. Urinary propionylcarnitine excretion averaged 11 nmol/day in control rats and 120 nmol/day in the vitamin B-12-deficient group. The fraction of total carnitine present as short-chain acylcarnitines in the plasma and liver of vitamin B-12-deficient rats was increased as compared with controls. When the rats were fasted for 48 h, relative or absolute increases were seen in the urine, plasma, liver and skeletal-muscle acylcarnitine content of the vitamin B-12-deficient rats as compared with controls. Thus vitamin B-12 deficiency was associated with a redistribution of carnitine towards acylcarnitines. Propionylcarnitine was a significant constituent of the acylcarnitine pool in the vitamin B-12-deficient animals. The changes in carnitine metabolism were consistent with the changes in CoA metabolism known to occur with vitamin B-12 deficiency. The vitamin B-12-deficient rat provides a model system for studying carnitine metabolism in the methylmalonic acidurias. PMID:3196310

  16. Terahertz gas sensor based on absorption-induced transparency

    Directory of Open Access Journals (Sweden)

    Rodrigo Sergio G.

    2016-01-01

    Full Text Available A system for the detection of spectral signatures of gases at the Terahertz regime is presented. The system consists in an initially opaque holey metal film whereby the introduction of a gas provokes the appearance of spectral features in transmission and reflection, due to the phenomenom of absorption-induced transparency (AIT. The peaks in transmission and dips in reflection observed in AIT occur close to the absorption energies of the molecules, hence its name. The presence of the gas would be thus revealed as a strong drop in reflectivity measurements at one (or several of the gas absorption resonances. As a proof of principle, we theoretically demonstrate how the AIT-based sensor would serve to detect tiny amounts of hydrocyanic acid.

  17. Vegan Diet, Subnormal Vitamin B-12 Status and Cardiovascular Health

    Directory of Open Access Journals (Sweden)

    Kam S. Woo

    2014-08-01

    Full Text Available Vegetarian diets have been associated with atherosclerosis protection, with healthier atherosclerosis risk profiles, as well as lower prevalence of, and mortality from, ischemic heart disease and stroke. However, there are few data concerning the possible cardiovascular effects of a vegan diet (with no meat, dairy or egg products. Vitamin B-12 deficiency is highly prevalent in vegetarians; this can be partially alleviated by taking dairy/egg products in lact-ovo-vegetarians. However, metabolic vitamin B-12 deficiency is highly prevalent in vegetarians in Australia, Germany, Italy and Austria, and in vegans (80% in Hong Kong and India, where vegans rarely take vitamin B-12 fortified food or vitamin B-12 supplements. Similar deficiencies exist in northern Chinese rural communities consuming inadequate meat, egg or dairy products due to poverty or dietary habits. Vascular studies have demonstrated impaired arterial endothelial function and increased carotid intima-media thickness as atherosclerosis surrogates in such metabolic vitamin B-12 deficient populations, but not in lactovegetarians in China. Vitamin B-12 supplementation has a favourable impact on these vascular surrogates in Hong Kong vegans and in underprivileged communities in northern rural China. Regular monitoring of vitamin B-12 status is thus potentially beneficial for early detection and treatment of metabolic vitamin B-12 deficiency in vegans, and possibly for prevention of atherosclerosis-related diseases.

  18. Causes of Vitamin B12 and Folate Deficiency

    Science.gov (United States)

    This review describes current knowledge of the main causes of vitamin B12 and folate deficiency. The most common explanations for poor B12 status are a low dietary intake of the vitamin (i.e., a low intake of animal-source foods) and malabsorption. Although it has long been known that strict vegetar...

  19. Vegan diet, subnormal vitamin B-12 status and cardiovascular health.

    Science.gov (United States)

    Woo, Kam S; Kwok, Timothy C Y; Celermajer, David S

    2014-08-19

    Vegetarian diets have been associated with atherosclerosis protection, with healthier atherosclerosis risk profiles, as well as lower prevalence of, and mortality from, ischemic heart disease and stroke. However, there are few data concerning the possible cardiovascular effects of a vegan diet (with no meat, dairy or egg products). Vitamin B-12 deficiency is highly prevalent in vegetarians; this can be partially alleviated by taking dairy/egg products in lact-ovo-vegetarians. However, metabolic vitamin B-12 deficiency is highly prevalent in vegetarians in Australia, Germany, Italy and Austria, and in vegans (80%) in Hong Kong and India, where vegans rarely take vitamin B-12 fortified food or vitamin B-12 supplements. Similar deficiencies exist in northern Chinese rural communities consuming inadequate meat, egg or dairy products due to poverty or dietary habits. Vascular studies have demonstrated impaired arterial endothelial function and increased carotid intima-media thickness as atherosclerosis surrogates in such metabolic vitamin B-12 deficient populations, but not in lactovegetarians in China. Vitamin B-12 supplementation has a favourable impact on these vascular surrogates in Hong Kong vegans and in underprivileged communities in northern rural China. Regular monitoring of vitamin B-12 status is thus potentially beneficial for early detection and treatment of metabolic vitamin B-12 deficiency in vegans, and possibly for prevention of atherosclerosis-related diseases.

  20. Vitamin B12 deficiency: issues in nursing care.

    Science.gov (United States)

    Candela, Lori; Meiner, Sue E

    2004-08-01

    Vitamin B12 deficiency is a relatively common occurrence with potentially devastating consequences. The wide range of etiologies and symptoms makes it imperative for the nurse to use a comprehensive approach to assessing and managing the patient with vitamin B12 deficiency.

  1. The relation between vitamin B12 and SYNTAX score.

    Science.gov (United States)

    Cerit, Levent; Duygu, Hamza; Gulsen, Kamil; Kemal, Hatice; Tosun, Ozgur; Ozcem, Barcin; Cerit, Zeynep; Gunsel, Aziz

    2017-01-01

    Vitamin B12 is required in the metabolism of homocysteine. Vitamin B12 deficiency has been implicated in endothelial dysfunction and cardiovascular disease via hyperhomocysteinaemia. However, the association of vitamin B12 and the severity of coronary artery disease has not been studied to date. This study was conducted with the aim of evaluating the relationship between vitamin B12 and SYNTAX score. Medical records of consecutive patients who underwent coronary artery bypass grafting surgery were retrospectively reviewed. The study group consisted of 127 patients. Vitamin B12, other biochemical parameters, clinical and echocardiographic parameters, and SYNTAX score were evaluated for all patients. Patients with vitamin B12 deficiency had a higher prevalence of cardiovascular risk factors such as diabetes mellitus, and history of transient ischaemic attack/stroke and heart failure. The SYNTAX score was significantly higher in patients with vitamin B12 deficiency (29.2 ± 4.9 vs. 22.5 ± 4.5, p vitamin B12 deficiency and SYNTAX score, demon-strating the severity and complexity of coronary artery disease.

  2. Dietary vitamin B12 deficiency in an adolescent white boy.

    Science.gov (United States)

    O'Gorman, P; Holmes, D; Ramanan, A V; Bose-Haider, B; Lewis, M J; Will, A

    2002-06-01

    Dietary deficiency of cobalamin resulting in tissue deficiency in white individuals is unusual. However, several patients with dietary deficiency who were neither vegan nor Hindu have been described. This report describes the case of a 14 year old boy who was a white non-Hindu with a very low intake of cobalamin, which was not apparent until a detailed dietary assessment was performed. The patient responded rapidly to a combination of oral and parenteral B12. This case illustrates the fact that severe dietary vitamin B12 deficiency can occur in non-Hindu white individuals. Inadequate dietary content of B12 may not be apparent until a detailed dietary assessment is performed. This patient is likely to have had subclinical vitamin B12 deficiency for several years. Increased vitamin B12 requirements associated with the adolescent growth spurt may have provoked overt tissue deficiency.

  3. Brain damage in infancy and dietary vitamin B12 deficiency.

    Science.gov (United States)

    Wighton, M C; Manson, J I; Speed, I; Robertson, E; Chapman, E

    1979-07-14

    A case of the exclusively breast-fed infant of a vegetarian mother is reported. Neurological deterioration commenced between three and six months of age, and progressed to a comatose premoribund state by the age of nine months. Investigations revealed a mild nutritional vitamin B12 deficiency in the mother, and a very severe nutritional B12 deficiency in the infant, with severe megaloblastic anaemia. Treatment of the infant with vitamin B12 resulted in a rapid clinical and haematological improvement, but neurological recovery was incomplete. Evidence is presented that dietary B12 deficiency was the sole cause of the infant's deterioration, and the literature relating to the condition is reviewed. It is recommended that all strict vegetarians (vegans), especially women in the child-bearing age group, take vitamin B12 supplements.

  4. The impact of vegan diet on B-12 status in healthy omnivores: five-year prospective study.

    Science.gov (United States)

    Mądry, Edyta; Lisowska, Aleksandra; Grebowiec, Philip; Walkowiak, Jarosław

    2012-04-02

    There are no long-term prospective studies assessing the impact of the vegan diet on vitamin B-12 (B-12) status. Many vegans take B-12 supplements irregularly or refuse to adopt them at all, considering them to be "unnatural" products. The use of B-12 fortified food may be an alternative. Therefore, we aimed to estimate the long-term effect of a vegan diet on serum B-12 concentrations in healthy omnivore adults, comparing the influence of natural products consumption and B-12 fortified food. A five year prospective study was carried out comprising 20 omnivore healthy adult subjects, who moved to strict vegan diet for 5 years. Ten volunteers followed vegan diet based entirely on natural products, while the remaining ten subjects consumed food fortified in B-12. In all subjects serum vitamin B-12 concentration was determined before and 6, 12, 24 and 60 months after the implementation of the diet. A significant decrease (p vegan diet. However, observed changes were in fact limited to the subgroup consuming exclusively natural products (p vegan diet is associated with the risk of vitamin B-12 deficiency. B-12 fortified products might constitute a valuable alternative in vegans refusing to take vitamin supplements.

  5. [Study of Terahertz Amplitude Imaging Based on the Mean Absorption].

    Science.gov (United States)

    Zhang, Zeng-yan; Ji, Te; Xiao, Ti-qiao; Zhao, Hong-wei; Chen, Min; Yu, Xiao-han; Tong, Ya-jun; Zhu, Hua-chun; Peng, Wei-wei

    2015-12-01

    A new method of terahertz (THz) imaging based on the mean absorption is proposed. Terahertz radiation is an electromagnetic radiation in the range between millimeter waves and far infrared. THz pulse imaging emerges as a novel tool in many fields because of its low energy and non-ionizing character, such as material, chemical, biological medicine and food safety. A character of THz imaging technique is it can get large amount of information. How to extract the useful parameter from the large amount of information and reconstruct sample's image is a key technology in THz imaging. Some efforts have been done for advanced visualization methods to extract the information of interest from the raw data. Both time domain and frequency domain visualization methods can be applied to extract information on the physical properties of samples from THz imaging raw data. The process of extracting useful parameter from raw data of the new method based on the mean absorption was given in this article. This method relates to the sample absorption and thickness, it delivers good signal to noise ratio in the images, and the dispersion effects are cancelled. A paper with a "THz" shape hole was taken as the sample to do the experiment. Traditional THz amplitude imaging methods in time domain and frequency domain are used to achieve the sample's image, such as relative reduction of pulse maximum imaging method, relative power loss imaging method, and relative power loss at specific frequency imaging method. The sample's information that reflected by these methods and the characteristics of these methods are discussed. The method base on the mean absorption within a certain frequency is also used to reconstruct sample's image. The experimental results show that this new method can well reflect the true information of the sample. And it can achieve a clearer image than the other traditional THz amplitude imaging methods. All the experimental results and theoretical analyses indicate that

  6. Fisiopatologia da deficiência de vitamina B12 e seu diagnóstico laboratorial Physiopathology of vitamin B12 deficiency and its laboratorial diagnosis

    Directory of Open Access Journals (Sweden)

    Clóvis Paniz

    2005-10-01

    synthetized by humans organisms, found in foods of animal origin. Its deficiency is very frequent among old people, vegetarians, subjects who use a low protein diet, or who present gastrointestinal absorption failure. PHYSIOPATHOLOGY: The vitamin B12 deficiency leads to hematologic, neurophatologic and cardiovascular disorders, mainly by interfering in the homocysteine (Hcy metabolism and in the methylation reactions of organism. Often, the deficiency can remain without symptoms for long time, leading to a chronic deficiency that, if not treated, may yield irreversible neurologic manifestations. METHODOLOGY: Efficient methodologies that allow the early diagnosis are essential. However, a gold standard method is not consensus yet. The vitamin B12 serum measurement presents some restrictions for problems of sensitivity and specificity, being able to occur deficiency’s symptoms even the serum vitamin B12 being in normal range or, in another way, occurring low levels of serum vitamin B12 without, however, showing low levels of vitamin B12 fraction really available for the cells and without showing symptoms. New alternatives come appearing, as the transcobalamin II measurement, the only vitamin B12 fraction available for the cells or the methylmalonic acid and Hcy measurement, metabolites that increase when intracellular vitamin B12 decreases. These tests present some advantages, but also important limitations for use in the routine. CONCLUSION: In the sub clinical cases, a correct and early diagnosis represents still a challenge and further studies are needed to define the best method for routine laboratorial diagnosis of vitamin B12 deficiency.

  7. Whey protein isolate improves vitamin B12 and folate status in elderly Australians with subclinical deficiency of vitamin B12.

    Science.gov (United States)

    Dhillon, Varinderpal S; Zabaras, Dimitrios; Almond, Theodora; Cavuoto, Paul; James-Martin, Genevieve; Fenech, Michael

    2017-05-01

    Whey protein isolate (WPI) contains vitamin B12 and folate. However, the efficacy of WPI as a bioavailable source of these vitamins in the elderly with low vitamin B12 was not previously tested. We investigated the effects of WPI supplementation on vitamin B12 and folate status in blood and measured changes in homocysteine (HCY), methylmalonic acid (MMA), and genome integrity biomarkers in elderly individuals with low vitamin B12 status. The effect of WPI was compared to soy protein isolate (SPI). In this randomized controlled cross-over intervention trial, 56 subclinically vitamin B12 -deficient participants received 50 g WPI or 50 g SPI as a control for 8 wk followed by 16-wk washout phase and then cross-over to alternative supplement for next 8 wk. Consumption of WPI resulted in significant increase in serum active B12 (p B12 and folate status. Unlike SPI, WPI consumption may prevent increase in MMA, HCY, and genome instability in older Australians with low vitamin B12 status. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Different Neurologic Aspects of Nutritional B12 Deficiency in Infancy.

    Science.gov (United States)

    Yilmaz, Sanem; Serdaroglu, Gul; Tekgul, Hasan; Gokben, Sarenur

    2016-04-01

    The objective of this study is to evaluate neurologic problems caused by nutritional vitamin B12 deficiency in infancy. Twenty-four cases between 2 and 18 months of age with neurologic symptoms and/or signs and diagnosed as nutritional vitamin B12 deficiency were analyzed. The most common symptoms were developmental retardation, afebrile seizures, and involuntary movements. The mean vitamin B12 levels were lower in patients with both neurologic and extraneurologic involvement when compared to those with only neurologic symptoms. All of the cases were treated with vitamin B12. In patients with severe deficiencies, involuntary movements were observed during vitamin B12 treatment using cyanocobalamin form. At the 1-year follow-up, all but 3 patients were considered neurodevelopmentally normal. The 3 patients that did not fully recover, on admission, had the lowest vitamin B12 levels. It is of great importance to prevent, diagnose, and treat vitamin B12 deficiency promptly to prevent the long-term neurologic problems.

  9. West syndrome due to vitamin B12 deficiency.

    Science.gov (United States)

    Serin, Hepsen Mine; Kara, Aslıhan Oruçoğlu; Oğuz, Baran

    2015-12-01

    Vitamin B12 is one of the essential vitamins affecting various systems of the body. Vitamin B12 deficiency in infants often produces haematological and neurological deficits including macrocyticanaemia, neurodevelopmental delay or regression, irritability, weakness, hypotonia, ataxia, apathy, tremor andseizures. In this article, we report the case of a six-month-old male patient diagnosed with West syndrome associated with vitamin B12 deficiency. Although the patient had no evidence of macrocytic anemia in complete blood count, we measured the level of vitamin B12 because the patient had hypotonicity and found it to be low. No other problem was found in the other investigations directed to the etiology of West syndrome. He was being exclusively breast-fed and vitamin B12 deficiency was related with nutritional inadequacy of his mother. Vitamin B12 deficiency should be considered in the differential diagnosis of patients presenting with different neurological findings. In addition, vitamin B12 deficiency should be considered as a rare cause in West syndrome which has a heterogeneous etiology.

  10. Organic/inorganic hybrid nanomaterials with vitamin B12 functions

    Directory of Open Access Journals (Sweden)

    Yoshio Hisaeda, Takahiro Masuko, Erika Hanashima and Takashi Hayashi

    2006-01-01

    Full Text Available A hybrid nanomaterial was prepared by human serum albumin (HSA and vitamin B12 derivatives. The incorporation of hydrophobic vitamin B12 derivatives, which have ester groups in place of the peripheral amide moieties of the natural cobalamin, into HSA is primarily controlled by the hydrophobicity of the peripheral ester groups. Microenvironmental property around the hydrophobic vitamin B12 in HSA was examined by fluorescence and fluorescence polarization measurements. The hydrophobic vitamin B12 itself in HSA is in a microenvironment equivalent in medium polarity to dichloromethane. The molecular motion of hydrophobic vitamin B12 in HSA was markedly suppressed under such microenvironmental conditions. Carbon-skeleton rearrangement reaction of an alkyl radical derived from an alkyl ligand bound to the hydrophobic vitamin B12 was markedly favored in HSA aqueous solution, relative to the reactions in methanol and benzene. The 1,2-migration of the electron-withdrawing group arises from both the suppression of molecular motion and desolvation effects on the alkylated hydrophobic vitamin B12 in HSA.

  11. Determination of Vitamin B12 in Vitamin B12 Compound Ointment- Ⅰ by HPLC%复方维生素B12软膏Ⅰ号中维生素B12的HPLC测定

    Institute of Scientific and Technical Information of China (English)

    杨谊; 李兵; 史学慧

    2004-01-01

    建立了HPLC法测定复方维生素B12软膏Ⅰ号中维生素B12的含量.采用Hypersll BDS C18柱,流动相为乙腈-0.05mol/L磷酸二氢钾溶液(15:85),检测波长360nm.维生素B12在0.16~0.8μg范围内线性关系良好(r=0.9995),平均回收率为98.4%,RSD为0.9%.

  12. The electronic structure and chemical bonding of vitamin B12

    Science.gov (United States)

    Kurmaev, E. Z.; Moewes, A.; Ouyang, L.; Randaccio, L.; Rulis, P.; Ching, W. Y.; Bach, M.; Neumann, M.

    2003-05-01

    The electronic structure and chemical bonding of vitamin B12 (cyanocobalamin) and B12-derivative (methylcobalamin) are studied by means of X-ray emission (XES) and photoelectron (XPS) spectroscopy. The obtained results are compared with ab initio electronic structure calculations using the orthogonalized linear combination of the atomic orbital method (OLCAO). We show that the chemical bonding in vitamin B12 is characterized by the strong Co-C bond and relatively weak axial Co-N bond. It is further confirmed that the Co-C bond in cyanocobalamin is stronger than that of methylcobalamin resulting in their different biological activity.

  13. [Severe vitamin B12 deficiency in infants breastfed by vegans].

    Science.gov (United States)

    Roed, Casper; Skovby, Flemming; Lund, Allan Meldgaard

    2009-10-19

    Weight loss and reduction of motor skills resulted in paediatric evaluation of a 10-month-old girl and a 12-month-old boy. Both children suffered form anaemia and delayed development due to vitamin B12 deficiency caused by strict maternal vegan diet during pregnancy and nursing. Therapy with cyanocobalamin was instituted with remission of symptoms. Since infants risk irreversible neurologic damage following severe vitamin B12 deficiency, early diagnosis and treatment are mandatory. Vegan and vegetarian women should take vitamin B12 supplementation during the pregnancy and nursing period.

  14. Impact of Vitamin B12 and Nitrate on Transcript and Metabolite Abundances in Marine Diatoms.

    Science.gov (United States)

    Pound, H. L.; Schanke, N. L.; Penta, W. B.; Zavala, J.; Casu, F.; Bearden, D. W.; Lee, P. A.

    2016-02-01

    Phytoplankton play countless roles in the support and regulation of marine ecosystems, as well as in global biogeochemical cycling processes. They are also, to varying extents, reliant on other physical and biological processes to supply their nutrient demands, such as the production of vitamin B12 by bacteria and archaea or the regeneration and upwelling of nitrate. One such process in the global biogeochemical sulfur cycle is the pathway that begins with the production of dimethylsulfoniopropionate (DMSP) by marine phytoplankton and leads to the atmospheric formation of sulfate-based cloud condensation nuclei, which contribute to the Earth's albedo. Nutrient limitation is thought to play a major role in the amount of DMSP produced by phytoplankton. Vitamin B12 and nitrate are of particular interest due to their involvement as a co-factor and nitrogen source, respectively, in the synthesis of methionine, the precursor for DMSP. Laboratory-based nutrient limitation experiments have been performed on cultures of the diatom Phaeodactylum tricornutum. In addition to the B12-dependent methionine synthase (MetH) P. tricornutum has a unique B12-independent methionine synthase gene (MetE). Based on classic techniques, B12 limitation had little impact on cell growth, whereas nitrate limitation had a significant effect on both culture health and DMSP concentration. Yet, targeted transcriptomic analysis (using Nanostring nCounter technology) and metabolomics analysis (using Nuclear Magnetic Resonance (NMR)) revealed complex changes in transcript abundance towards upregulated gene expression associated with the MetE gene in B12 limited cultures, and shifts away from nitrogen-based metabolites towards DMSP in nitrate-limited cultures. These experiments help verify the role of B12 in DMSP production and link the underlying metabolic pathways that drive the cellular portion of the sulfur cycle to ecosystem and global scale processes.

  15. Mielopatia por deficiência de vitamina B12 apresentando-se como mielite transversa Myelopathy due to vitamin B12 deficiency presenting as transverse myelitis

    Directory of Open Access Journals (Sweden)

    Luiz Felipe Rocha Vasconcellos

    2002-03-01

    Full Text Available As manifestações neurológicas associadas à deficiência de vitamina B12 incluem polineuropatia, mielopatia, demência e neuropatia óptica. O diagnóstico laboratorial é feito através da dosagem sérica de cianocobalamina ou homocisteína e da excreção urinária de ácido metilmalônico. No estudo anatomopatológico observa-se na microscopia a destruição da mielina e de axônios vistos na substância branca. A região mais comumente afetada é o cordão posterior cervical e/ou torácico. O acometimento da coluna lateral é raro, ocorrendo em casos graves e avançados. O tratamento consiste na reposição de vitamina B12 e a resposta depende da gravidade do quadro e do tempo transcorrido entre o inicio dos sintomas e inicio do tratamento. Relatamos o caso de um paciente que apresentou, como manifestação de deficiência de vitamina B12, mielite transversa. O estudo morfológico da medula demonstrou comprometimento dos tractos cortico-espinhais lateral e anterior, da coluna dorsal e ainda do tracto espino-talâmico.Vitamin B12 deficiency may induce neuropathy, myelopathy, dementia and optic neuropathy. The diagnosis is established by vitamin B12, homocysteine and methylmalonic acid measurements. Myelin and axon destruction in the white matter of the spinal cord are observed. The posterior column of the cervical and thoracic level is the most common involved area. The involvement of the anterior column is restricted to advanced and relatively severe cases. Treatment is based on vitamin B12 injections, and the prognosis depends on the stage of vitamin deficiency and deterioration at treatment onset. We report a case with transverse myelitis due to vitamin B12 deficiency. This picture is relatively uncommon, however, we believe patients with transverse myelitis should have vitamin B12 studies as part of the diagnosis work up.

  16. The photochemical mechanism of a B12-dependent photoreceptor protein

    Science.gov (United States)

    Kutta, Roger J.; Hardman, Samantha J. O.; Johannissen, Linus O.; Bellina, Bruno; Messiha, Hanan L.; Ortiz-Guerrero, Juan Manuel; Elías-Arnanz, Montserrat; Padmanabhan, S.; Barran, Perdita; Scrutton, Nigel S.; Jones, Alex R.

    2015-08-01

    The coenzyme B12-dependent photoreceptor protein, CarH, is a bacterial transcriptional regulator that controls the biosynthesis of carotenoids in response to light. On binding of coenzyme B12 the monomeric apoprotein forms tetramers in the dark, which bind operator DNA thus blocking transcription. Under illumination the CarH tetramer dissociates, weakening its affinity for DNA and allowing transcription. The mechanism by which this occurs is unknown. Here we describe the photochemistry in CarH that ultimately triggers tetramer dissociation; it proceeds via a cob(III)alamin intermediate, which then forms a stable adduct with the protein. This pathway is without precedent and our data suggest it is independent of the radical chemistry common to both coenzyme B12 enzymology and its known photochemistry. It provides a mechanistic foundation for the emerging field of B12 photobiology and will serve to inform the development of a new class of optogenetic tool for the control of gene expression.

  17. La Vitamine B12 et la Santé

    OpenAIRE

    VALDES SOCIN, Hernan Gonzalo

    2013-01-01

    Objectifs: Révision sur le rôle de la vitamine B12 et sur les évidences qui suggèrent que la vitamine B12 peut réduire le risque de certaines maladies chroniques. Evidences: recherche dans Medline depuis 1999 jusqu'en 2013 en utilisant le mot clé vitamin B12. Les articles les plus conséquents (150) étaient associés avec le cancer, la maladie cardiovasculaire, la santé mentale et les altérations du tube neural. Résultats: Le déficit avéré de la vitamine B12 est classiquement associé à...

  18. Vitamine B12, D, foliumzuur en leeftijdgerelateerde aandoeningen

    NARCIS (Netherlands)

    Brouwer, E.M.; Wijngaarden, van J.P.

    2011-01-01

    Dat vitaminen en mineralen een positieve invloed uit kunnen oefenen op specifieke lichaamsprocessen is bekend. Twee promovendi van Wageningen Universiteit richten zich op het mogelijke verband tussen vitamine B12, foliumzuur en vitamine D en verschillende leeftijdgerelateerde aandoeningen. De associ

  19. Reductive Dechlorination of Chlorophenois by Vitamin B12

    Science.gov (United States)

    1993-06-01

    1978), and diffusion-controlled reactions are unaffected by mixing in batch reactors ( Levenspiel , 1972). However, the two experiments which exhibited...were developed, including a novel reactor system, for conducting these experints. Most of the experiments were conducted in either hermetically-sealed...glass ampoulem, which could maintain vitamin B12 in the fully-reduced vitamin B12, state for months, or in the novel two-chambered reactor (TCR), which

  20. Competitive immunoassay for analysis of vitamin B(12).

    Science.gov (United States)

    Selva Kumar, L Sagaya; Thakur, M S

    2011-11-15

    In the current work, direct competitive enzyme-linked immunosorbent assay (ELISA) was developed for derivatized vitamin B(12) by generating chicken egg yolk immunoglobulins (IgY) against derivatized vitamin B(12) and purified using affinity chromatography. Checkerboard assay was performed with vitamin B(12) antibody and vitamin B(12)-alkaline phosphatase conjugate followed by its conjugate characterization using ultraviolet (UV) spectroscopy and high-performance liquid chromatography (HPLC). The limit of detection was 10 ng/ml with a linear working range of 10 to 10,000 ng/ml. The affinity constant (K(a)) of the vitamin B(12) antibody was found to be 4.23×10(8) L/mol. Cross-reactivity with other water-soluble vitamins was found to be less than 0.01% except for analogs of vitamin B(12) that showed 12% to 35%. The intra- and interassay coefficients of variation were found to be in the ranges from 0.0005% to 1.2% and 0.009% to 1.03%, respectively. The assay was validated with the HPLC method in terms of sensitivity, specificity, precision, and recovery of vitamin B(12) with spiked multivitamin injections, tablets, capsules, and chocolates. The HPLC method had a detection limit of 500 ng/ml with a linear working range of 1000 to 10,000 ng/ml. After extraction of vitamin B(12) using Amberlite XAD, the developed ELISA method correlated well with the established HPLC method with a correlation coefficient of 0.90.

  1. Vitamin B12 deficiency. Important new concepts in recognition.

    Science.gov (United States)

    Goodman, K I; Salt, W B

    1990-09-01

    Vitamin B12 deficiency develops over a slowly progressive continuum. Early manifestations may be generalized weakness or fatigue, indigestion, diarrhea, or depression. Pernicious anemia is considered the classic cause, but others include malabsorption because of achlorhydria or other gastric dysfunction, fish tapeworm infection, and strict vegetarianism. Iron deficiency often coexists. Because presentation is often atypical, vitamin B12 deficiency is a diagnostic consideration whenever neuropsychiatric signs or symptoms are unexplained.

  2. Metformin Use and Vitamin B12 Deficiency: Untangling the Association.

    Science.gov (United States)

    Rodríguez-Gutiérrez, René; Montes-Villarreal, Juan; Rodríguez-Velver, Karla Victoria; González-Velázquez, Camilo; Salcido-Montenegro, Alejandro; Elizondo-Plazas, Anasofia; González-González, José Gerardo

    2017-08-01

    Current evidence linking vitamin B12 deficiency with metformin use is inconsistent. Hence, there is uncertainty regarding the diagnostic approach in this scenario. Furthermore, this possible association has not been studied in the complete spectrum of patients with diabetes. We conducted a cross-sectional, controlled study with the objective of assessing differences in serum vitamin B12 levels among patients with and without diabetes with different metformin-treatment regimens. A total of 150 participants were recruited: patients with diabetes (group 1: metformin alone ≥850mg/day, group 2: patients with type 2 diabetes naive to treatment and group 3: metformin ≥850mg/day, in addition to any other oral glucose lowering agent or insulin, or both) and without diabetes (group 4: polycystic ovary syndrome or group 5: healthy individuals). Serum vitamin B12, folate levels and complete blood counts were obtained for the entire population. Methylmalonic acid and homocysteine were obtained for patients when vitamin B12 levels were found to be borderline or low. When patients with or without diabetes were compared, no significant difference was found in relation to their vitamin B12 levels (517.62 versus 433.83; P = 0.072). No difference in vitamin B12 levels was found among participants with metformin use and metformin naive participants (503.4 versus 462.3; P = 0.380). Irrespective of metformin use, no significant difference in the serum levels of vitamin B12 was observed, both in patients with and without diabetes. In the light of the body of evidence and the results of this study, a universal recommendation for vitamin B12 deficiency screening cannot be made. Copyright © 2017 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.

  3. Analysis of the Market of Vitamin B12%维生素B12市场透析

    Institute of Scientific and Technical Information of China (English)

    张伦

    2004-01-01

    目的:掌握维生素 B12的市场现状及发展趋势.方法:对维生素 B12国内、外生产和销售情况进行分析.结果与结论:我国维生素 B12市场潜力巨大,制药企业应密切关注市场变化,完善自身条件,以求进一步发展.

  4. A rare case of vitamin B12 deficiency with ascites.

    Science.gov (United States)

    Rajsekhar, Putta; Reddy, Mugannagari Maheshwar; Vaddera, Sameeraja; Rajini, G; Tikeli, Vinil

    2014-07-01

    Vitamin B12 deficiency is widespread than assumed in population. At risk are older people, pregnant women, vegans, patients with renal and intestinal diseases. Vitamin B12 deficiency can present with various hematological, gastrointestinal and neurological manifestations. In the population, the prevalence of vitamin B12 deficiency in younger people is 5% to 7% which is less compared to elderly people. In developing countries, deficiency is much more common, starting in early life and persisting across the life span. Here, we present a 16-year-old female patient presenting with ascites since 2 months who was subsequently investigated and diagnosed to have nutritional megaloblastic anaemia secondary to vitamin B12 deficiency after exclusion of other infective, neoplastic, autoimmune and inflammatory diseases. Inspite, patient was treated with antitubercular drugs but she did not respond. After supplementation of Vitamin B12, ascites responded well. Inadequate intake due to low consumption of animal source foods is the main cause of low serum vitamin B12 in younger adults and likely the main cause in poor population worldwide.

  5. How prevalent is vitamin B(12) deficiency among vegetarians?

    Science.gov (United States)

    Pawlak, Roman; Parrott, Scott James; Raj, Sudha; Cullum-Dugan, Diana; Lucus, Debbie

    2013-02-01

    Vegetarians are at risk for vitamin B(12) (B12) deficiency due to suboptimal intake. The goal of the present literature review was to assess the rate of B12 depletion and deficiency among vegetarians and vegans. Using a PubMed search to identify relevant publications, 18 articles were found that reported B12 deficiency rates from studies that identified deficiency by measuring methylmalonic acid, holo-transcobalamin II, or both. The deficiency rates reported for specific populations were as follows: 62% among pregnant women, between 25% and almost 86% among children, 21-41% among adolescents, and 11-90% among the elderly. Higher rates of deficiency were reported among vegans compared with vegetarians and among individuals who had adhered to a vegetarian diet since birth compared with those who had adopted such a diet later in life. The main finding of this review is that vegetarians develop B12 depletion or deficiency regardless of demographic characteristics, place of residency, age, or type of vegetarian diet. Vegetarians should thus take preventive measures to ensure adequate intake of this vitamin, including regular consumption of supplements containing B12.

  6. Cascaded process model based control: packed absorption column application.

    Science.gov (United States)

    Govindarajan, Anand; Jayaraman, Suresh Kumar; Sethuraman, Vijayalakshmi; Raul, Pramod R; Rhinehart, R Russell

    2014-03-01

    Nonlinear, adaptive, process-model based control is demonstrated in a cascaded single-input-single-output mode for pressure drop control in a pilot-scale packed absorption column. The process is shown to be nonlinear. Control is demonstrated in both servo and regulatory modes, for no wind-up in a constrained situation, and for bumpless transfer. Model adaptation is demonstrated and shown to provide process insight. The application procedure is revealed as a design guide to aid others in implementing process-model based control.

  7. Optical humidity detection based on tunable diode laser absorption spectroscopy

    Science.gov (United States)

    Zhang, Keke; Liu, Shixuan; Chen, Shizhe; Zhao, Qiang; Zhang, Lijuan; Li, Xuanqun; Wang, Wenyan; Wu, Yushang

    2017-02-01

    Humidity is an important environmental parameter, which is difficult to be measured accurately and quickly using traditional measurement methods. Under the environment of low temperature or high humidity, traditional humidity and temperature sensor has shortages in humidity measurement accuracy, corresponding time and wet fade speed. To solve these problems, this paper proposes a method to measure the environmental humidity with wavelength modulation technology and harmonic detection technology based on tunable diode laser absorption spectroscopy. H2O molecular absorption line near 1392 nm is selected as the characteristic spectra. The effects of temperature, pressure and water concentration on the absorption spectrum width, the wavelength modulation coefficient and the amplitude of the harmonic signal are analyzed. Humidity and temperature sensor is modified using temperature and pressure compensation model, and the influence of the water concentration variation is eliminated by the iterative algorithm. The new humidity and temperature sensor prototype is developed, and the structure of the optical system is simple, which is easy to be adjusted. The response frequency of the humidity detection is 40 Hz. The experiment was carried out for 3 months at Qingdao national basic weather station. Experimental results show that the consistency of the humidity and temperature data is very good, which can proves the validity of the humidity measurement technology.

  8. Stabilization of HfB12 in Y1-xHfxB12 under Ambient Pressure.

    Science.gov (United States)

    Akopov, Georgiy; Yeung, Michael T; Turner, Christopher L; Li, Rebecca L; Kaner, Richard B

    2016-05-16

    Alloys of metal dodecaborides-YB12 with HfB12-were prepared via arc-melting in order to stabilize the metastable HfB12 high-pressure phase under ambient pressure. Previously, HfB12 had been synthesized only under high-pressure (6.5 GPa). Powder X-ray diffraction (PXRD) and energy-dispersive X-ray spectroscopy (EDS) were used to confirm the purity and phase composition of the prepared samples. The solubility limit for HfB12 in Y1-xHfxB12 (cubic UB12 structure type) was determined to be ∼35 at. % Hf by PXRD and EDS analysis. The value of the cubic unit cell parameter (a) changed from 7.505 Å (pure YB12) to 7.454 Å across the solid solution range. Vickers hardness increased from 40.9 ± 1.6 GPa for pure YB12 to 45.0 ± 1.9 GPa under an applied load of 0.49 N for the Y1-xHfxB12 solid solution composition with ∼28 at. % Hf, suggesting both solid solution hardening and extrinsic hardening due to the formation of secondary phases of hafnium.

  9. Vitamin B12 status in metformin treated patients: systematic review.

    Directory of Open Access Journals (Sweden)

    Qilin Liu

    Full Text Available OBJECTIVE: Randomized controlled trials and observational studies have yielded inconsistent results on the effects of metformin on vitamin B12 reduction. We therefore performed a systematic review to analyze the effects of metformin on vitamin B12 concentration. METHODS: PubMed, Medline, Embase, and the Cochrane central registry of controlled trials were searched to identify randomized controlled trials and observational studies exploring the association between metformin and vitamin B12 concentration in patients with type 2 diabetes mellitus or polycystic ovary syndrome. The main outcome measure was changes in serum vitamin B12 concentration after 6-208 weeks of treatment with metformin, as compared with placebo or other anti-hyperglycemic therapy. RESULTS: Six randomized controlled trials met the inclusion criteria. Serum vitamin B12 concentrations were significantly lower in patients treated with metformin than in those who received placebo or rosiglitazone (mean difference [MD], -53.93 pmol/L; 95% confidence interval [CI], -81.44 to -26.42 pmol/L, P = 0.0001. Subgroup analysis identified four trials in which patients received a lower dose of metformin (<2000 mg/d and two in which they received a higher dose (≥2000 mg/d, with MDs in vitamin B12 concentration after metformin treatment of -37.99 pmol/L (95% CI, -57.44 to -18.54 pmol/L, P = 0.0001 and -78.62 pmol/L (95% CI, -106.37 to -50.86 pmol/L, P<0.00001, respectively. CONCLUSIONS: The reduction of vitamin B12 may be induced by metformin in a dose dependent manner.

  10. Biosynthesis of vitamin B12 in anaerobic bacteria--experiments with Eubacterium limosum on the transformation of 5-hydroxy-6-methyl-benzimidazole, its nucleoside, its cobamide, and of 5-hydroxybenzimidazolylcobamide in vitamin B12.

    Science.gov (United States)

    Schulze, B; Vogler, B; Renz, P

    1998-06-15

    In anaerobic bacteria 5-hydroxybenzimidazole and 5-hydroxy-6-methylbenzimidazole are precursors of the 5,6-dimethylbenzimidazole moiety of vitamin B12. In order to elucidate the pathway from these bases to vitamin B12, experiments on the transformation of 5-hydroxy-6-methylbenzimidazole, of 5-hydroxy-6-methylbenzimidazole-alpha-D-ribofuranoside, of 5-hydroxybenzimidazolylcobamide and of 5-hydroxy-6-methylbenzimidazolylcobamide into vitamin B12 were carried out. The vitamin B12 synthesized by the anaerobe Eubacterium limosum in the presence of 5-hydroxy-6-methylbenzimidazole and L-[methyl-13C]methionine was subjected to NMR spectroscopy. It revealed that the methyl group at C5 of the 5,6-dimethylbenzimidazole moiety was 13C labeled, whereas the methyl group at C6 was unlabeled. This shows that the transformation of 5-hydroxy-6-methylbenzimidazole into the base moiety of vitamin B12 occurs regiospecifically. 5-Hydroxy-6-methylbenzimidazole-alpha-D-ribofuranoside as well as 5-hydroxybenzimidazolylcobamide and 5-hydroxy-6-methylbenzimidazolylcobamide were also transformed into vitamin B12 by E. limosum. When 5-hydroxy-6-methylbenzimidazolylcobamide 13C labeled at C2 of the base part and 14C labeled in the ribose was used for this experiment, the vitamin B12 obtained from this cobamide was 13C and 14C labeled in the same positions. This demonstrates that the alpha-glycosidic bond of the precursor cobamide is not split during the formation of vitamin B12. It can be deduced from these results that the precursor bases are transformed regiospecifically into their alpha-nucleotides, and partially into their cobamides. The alpha-nucleotides are then transformed into alpha-ribazole-5'-phosphate and, subsequently, into vitamin B12. Most likely the cobamides are degraded to the alpha-nucleotides before being used for the biosynthesis of vitamin B12. A pathway for the latter process is suggested.

  11. Oral Cyanocobalamin is Effective in the Treatment of Vitamin B12 Deficiency in Crohn's Disease.

    Science.gov (United States)

    Gomollón, Fernando; Gargallo, Carla J; Muñoz, Jose Fernando; Vicente, Raquel; Lue, Alberto; Mir, Alberto; García-Alvarado, Marta; Gracia, Marta; García-López, Santiago

    2017-03-20

    Cobalamin deficiency is common in patients with Crohn's disease (CD). Intramuscular cobalamin continues to be the standard therapy for the deficiency and maintenance treatment in these patients, although oral route has been demonstrated to be effective in other pathologies with impaired absorption. Our aims were to evaluate the efficacy of oral therapy in the treatment of cobalamin deficiency and in long-term maintenance in patients with Crohn's disease. We performed a multicenter retrospective cohort study that included 94 patients with Crohn's disease and cobalamin deficiency. Seventy-six patients had B12 deficiency and 94.7% of them normalized their cobalamin levels with oral treatment. The most used dose was 1 mg/day, but there were no significant differences in treatment effectiveness depending on the dose used (≥1 mg/24 h vs. cyanocobalamin provides effective acute and maintenance treatment for vitamin B12 deficiency caused by CD with or without ileum resection.

  12. Effect of Homocysteine ,Vitamin B12 , Folic acid during pregnancy

    Directory of Open Access Journals (Sweden)

    Arpita Patel

    2012-07-01

    Full Text Available Vitamin B12, folic acid and homocysteine are metabolically closely related. At the same time homocysteine is found to be offending factor for vascular pathology causing preeclampsia. On the other hand periconceptional nutritional status influences the vitamin B12 & folic acid level. Which further affect the homocysteine level thus may affect pregnancy outcome. Various contributory factors lead these vitamin deficiencies, maternal nutrition is one of them. Ahmedabad being a predominantly vegetarian city, its population is at higher risk of vitamin B12 deficiency. But no systematic study has been done in Ahmedabad to know whether B12, folic acid and homocysteine levels influence pregnancy. To know this answer this study was planned to know total homocysteine level and its correlation in preeclampsia and normotensive pregnant women.Vitamin B12, folic acid and homocysteine were measured in all the subjects using fluorescence polarized immunoassay in AxSym Immunochemistry analyzer on 60 non vitamin supplemented vegetarian women. Vitamin levels were within lower normal limit. Homocysteine level was higher among preeclampsia patient. From the findings of the present study it can be concluded that measurement of these biochemical parameter in ante natal care are useful for further management and prevention of complication of pregnancy like preeclampsia

  13. Neurological consequences of vitamin B12 deficiency and its treatment.

    Science.gov (United States)

    Chalouhi, Christel; Faesch, Sabine; Anthoine-Milhomme, Marie-Constance; Fulla, Yvonne; Dulac, Olivier; Chéron, Gérard

    2008-08-01

    In developed countries, the vitamin B12 deficiency usually occurs in children exclusively breast-fed, whose mothers are vegetarians, causing low stores of vitamin B12. Symptoms of vitamin B12 deficiency appear during the second trimester of life and include failure to thrive, lethargy, hypotonia, and arrest or regression of developmental skills. A megaloblastic anemia can be present. One half of the infants exhibit abnormal movements before the start of treatment with intramuscular cobalamin, which disappear 1 or 2 days after. More rarely, movement disorders appear a few days after treatment, whereas neurological symptoms are improving. These abnormal movements can last for 2 to 6 weeks. If not treated, vitamin B12 deficiency can cause lasting neurodisability. Therefore, efforts should be directed to preventing deficiency in pregnant and breast-feeding women on vegan diets and their infants by giving them vitamin B12 supplements. When preventive supplementation has failed, one should recognize and treat quickly an infant presenting with failure to thrive and delayed development.

  14. Causes of vitamin B12 and folate deficiency.

    Science.gov (United States)

    Allen, Lindsay H

    2008-06-01

    This review describes current knowledge of the main causes of vitamin B12 and folate deficiency. The most common explanations for poor vitamin B12 status are a low dietary intake of the vitamin (i.e., a low intake of animal-source foods) and malabsorption. Although it has long been known that strict vegetarians (vegans) are at risk for vitamin B12 deficiency, evidence now indicates that low intakes of animal-source foods, such as occur in some lacto-ovo vegetarians and many less-industrialized countries, cause vitamin B12 depletion. Malabsorption of the vitamin is most commonly observed as food-bound cobalamin malabsorption due to gastric atrophy in the elderly, and probably as a result of Helicobacter pylori infection. There is growing evidence that gene polymorphisms in transcobalamins affect plasma vitamin B12 concentrations. The primary cause of folate deficiency is low intake of sources rich in the vitamin, such as legumes and green leafy vegetables, and the consumption of these foods may explain why folate status can be adequate in relatively poor populations. Other situations in which the risk of folate deficiency increases include lactation and alcoholism.

  15. Enhancing vitamin B12 content in soy-yogurt by Lactobacillus reuteri.

    Science.gov (United States)

    Gu, Qing; Zhang, Chen; Song, Dafeng; Li, Ping; Zhu, Xuan

    2015-08-03

    More attention from the aged and vegetarians has been paid to soy-product due to its taste, easy digestibility, as well as the association with health. However, soy-product has a defect of low vitamin content, mainly the water-soluble vitamin B12. This study was to investigate co-fermentation of glycerol and fructose in soy-yogurt to enhance vitamin B12 production by Lactobacillus reuteri. After a serial combination experiments, the co-fermentation was confirmed to enhance the production of vitamin B12 up to 18 μg/100mL. Both supplementations induced the expression of cobT and cbiA and functioned to balance the redox reaction. Meanwhile, high content of fructose supplementation reduced the production of vitamin B12 and suppressed expression of cobT in bacteria. It was proved that the vitamin B12 content of this soy-yogurt is higher than other fermented soybean based food and thus can be served as an alternative food for the aged and vegetarians.

  16. Relation between blood vitamin B12 levels with premature ejaculation: case-control study.

    Science.gov (United States)

    Kadihasanoglu, M; Kilciler, M; Kilciler, G; Yucetas, U; Erkan, E; Karabay, E; Toktas, M G; Kendirci, M

    2016-09-29

    The aim of this study was to investigate whether vitamin B12 levels are associated with premature ejaculation (PE). A total of 109 subjects (56 PE and 53 controls) were included in this study. PE was defined as self-reported intravaginal ejaculatory latency time (IELT) based on the Diagnostic and Statistical Manual of Mental Disorders IV criteria and those who had had an IELT of premature ejaculation diagnostic tool (PEDT), International Index of Erectile Function (IIEF) and Beck Depression Inventory (BDI). The vitamin 12 levels were measured in all subjects. The mean age between the PE and controls was comparable (p = .084). Mean IIEF and BDI scores between the two groups did not statistically differ. The mean IELT values in the PE group were significantly lower than in the control group (p < .0001). PE patients reported significantly lower vitamin B12 levels compared with the controls (213.14 vs. 265.89 ng ml(-1) ; p < .001). The ROC analysis showed a significant correlation between the diagnosis of PE and lower vitamin B12 levels. This study has demonstrated that lower vitamin B12 levels are associated with the presence of PE. This work also shows a strong correlation between vitamin B12 levels and the PEDT scores as well as the IELT values.

  17. Infantile tremor syndrome: Role of Vitamin B12 revisited

    Directory of Open Access Journals (Sweden)

    Rajesh Gupta

    2016-01-01

    Full Text Available Objective: To study the role of Vitamin B12 as an etiological factor in patients of infantile tremor syndrome (ITS. Methods: Twelve consecutive admissions of children diagnosed clinically as ITS were assessed. Assessment was done using a predefined pro forma to document patient demographic factors, general examination, systemic examination as well as relevant hematological and biochemical investigations. Results: Out of the 12 cases of ITS, 6 were males and 6 were females. Two cases had serum B12 levels below reference values, five had levels in low normal range, and remaining five had normal values. Conclusions: Role of Vitamin B12 deficiency as an etiological factor in the patients of ITS is inconclusive.

  18. Serum vitamin B12 and blood cell values in vegetarians.

    Science.gov (United States)

    Dong, A; Scott, S C

    1982-01-01

    Serum vitamin B12 and complete blood count values were determined for 83 volunteer subjects from an American vegetarian society conference (USA). Among subjects who did not supplement their diets with vitamin B12 or multiple vitamin tablets, 92% of the vegans (total vegetarians), 64% of the lactovegetarians, 47% of the lacto-ovovegetarians and 20% of the semivegetarians had serum vitamin B12 levels less than 200 pg/ml (normal = 200-900 pg/ml). However, their complete blood count values did not deviate greatly from those found for nonvegetarians, even though some had been vegans or lactovegetarians for over 10 years. Macrocytosis among the vegetarians was minimal; none had mean corpuscular volume greater than 103 fl.

  19. Oxidative Stress Markers in Vitamin B12 Deficiency.

    Science.gov (United States)

    Misra, Usha Kant; Kalita, Jayantee; Singh, Sandeep Kumar; Rahi, Sushil Kumar

    2017-03-01

    In this study, we report the status of oxidative stress markers in vitamin B12 deficiency and their relation to clinical, laboratory, and neurophysiological findings. Fifty-one subjects with serum vitamin B12 deficiency (B12 deficiency patients groups as well as with normal controls. In the patients, GSH, MDA and TAC were correlated with demographic, clinical, hematological, biochemical, nerve conduction study (NCS), visual evoked potential (VEP) and somatosensory-evoked potential (SEP) findings. In the study group, 20 (39.2 %) patients had SACD manifesting with myeloneuropathy, cognitive or behavioral abnormalities, and 31(60.8 %) patients had non-SACD neurological manifestations. The GSH (2.46 ± 0.32 vs. 2.70 ± 0.36 mg/dl; P = 0.002) and TAC (2.13 ± 0.38 vs. 2.33 ± 0.24 nmol Trolox eq/l, P = 0.005) levels were lower, and MDA levels (4.01 ± 0.69 vs. 3.00 ± 0.45 nmol/ml, P B12 deficiency group compared with controls. Similar trend was found in SACD and non-SACD vitamin B12 deficiency groups. GSH levels correlated with abnormal VEP (r = 0.54; P B12 deficiency was associated with reduction in GSH and TAC and increase in MDA levels which were more marked in SACD compared to non-SACD group.

  20. Vitamin B12 deficit and development of geriatric syndromes

    Directory of Open Access Journals (Sweden)

    Ocampo Chaparro, José Mauricio

    2013-03-01

    Full Text Available Vitamin B12 deficiency or cyanocobalamin is a common condition in the elderly. It is repeatedly overlooked due to multiple clinical manifestations that can affect the blood, neurological, gastrointestinal, and cardiovascular systems, skin and mucous membranes. The various presentations of vitamin B12 deficiency are related to the development of geriatric syndromes like frailty, falls, cognitive impairment, and geriatric nutritional syndromes like protein-energy malnutrition and failure to thrive, in addition to enhancing aging anorexia and cachexia. Therefore, interventions must be developed to include their screening and diagnosis to make early and appropriate treatment to prevent its complications before they become irreversible.

  1. Investigation of the binding affinity in vitamin B12-Bovine serum albumin system using various spectroscopic methods

    Science.gov (United States)

    Makarska-Bialokoz, Magdalena

    2017-09-01

    The binding affinity between vitamin B12 (VitB12) and bovine serum albumin (BSA) has been investigated in aqueous solution at pH = 7.4, employing UV-vis absorption and steady-state, synchronous and three-dimensional fluorescence spectra techniques. Representative effects noted for BSA intrinsic fluorescence resulting from the interactions with VitB12 confirm the formation of π-π stacked non-covalent and non-fluorescent complexes in the system VitB12-BSA. All the determined parameters, the binding, fluorescence quenching and bimolecular quenching rate constants (of the order of 104 L mol- 1, 103 L mol- 1 and 1011 L mol- 1 s- 1, respectively), as well as Förster resonance energy transfer parameters validate the mechanism of static quenching. The interaction with VitB12 induces folding of the polypeptide chains around Trp residues of BSA, resulting in a more hydrophobic surrounding. Presented outcomes suggest that the addition of VitB12 can lead to the more organized BSA conformation and its more folded tertiary structure, what could influence the physiological functions of bovine serum albumin, notably in case of its overuse or abnormal metabolism.

  2. Vitamin B-12 Concentrations in Breast Milk Are Low and Are Not Associated with Reported Household Hunger, Recent Animal-Source Food, or Vitamin B-12 Intake in Women in Rural Kenya.

    Science.gov (United States)

    Williams, Anne M; Chantry, Caroline J; Young, Sera L; Achando, Beryl S; Allen, Lindsay H; Arnold, Benjamin F; Colford, John M; Dentz, Holly N; Hampel, Daniela; Kiprotich, Marion C; Lin, Audrie; Null, Clair A; Nyambane, Geoffrey M; Shahab-Ferdows, Setti; Stewart, Christine P

    2016-05-01

    Breast milk vitamin B-12 concentration may be inadequate in regions in which animal-source food consumption is low or infrequent. Vitamin B-12 deficiency causes megaloblastic anemia and impairs growth and development in children. We measured vitamin B-12 in breast milk and examined its associations with household hunger, recent animal-source food consumption, and vitamin B-12 intake. In a cross-sectional substudy nested within a cluster-randomized trial assessing water, sanitation, hygiene, and nutrition interventions in Kenya, we sampled 286 women 1-6 mo postpartum. Mothers hand-expressed breast milk 1 min into a feeding after 90 min observed nonbreastfeeding. The Household Hunger Scale was used to measure hunger, food intake in the previous week was measured with the use of a food-frequency questionnaire (FFQ), and vitamin B-12 intake was estimated by using 24-h dietary recall. An animal-source food score was based on 10 items from the FFQ (range: 0-70). Breast milk vitamin B-12 concentration was measured with the use of a solid-phase competitive chemiluminescent enzyme immunoassay and was modeled with linear regression. Generalized estimating equations were used to account for correlated observations at the cluster level. Median (IQR) vitamin B-12 intake was 1.5 μg/d (0.3, 9.7 μg/d), and 60% of women consumed vitamin B-12 concentration was 113 pmol/L (61, 199 pmol/L); 89% had concentrations food score ranged from 0 to 30 item-d/wk. Hunger and recent animal-source food and vitamin B-12 intake were not associated with breast milk vitamin B-12 concentrations. Maternal age was negatively associated with breast milk vitamin B-12 concentrations. Most lactating Kenyan women consumed less than the estimated average requirement of vitamin B-12 and had low breast milk vitamin B-12 concentrations. We recommend interventions that improve vitamin B-12 intake in lactating Kenyan women to foster maternal health and child development. The main trial was registered at

  3. Dietary sources of vitamin B-12 and their association with vitamin B-12 status markers in healthy older adults in the B-PROOF study

    NARCIS (Netherlands)

    E.M. Brouwer-Brolsma (Elske); R.A.M. Dhonukshe-Rutten (Rosalie); J.P. van Wijngaarden (Janneke); N.L. van der Zwaluw (N.); N. van der Velde (Nathalie); L.C.P.G.M. de Groot (Lisette)

    2015-01-01

    textabstractLow vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations

  4. Maximal load of the vitamin B12 transport system: a study on mice treated for four weeks with high-dose vitamin B12 or cobinamide.

    Directory of Open Access Journals (Sweden)

    Dorte L Lildballe

    Full Text Available Several studies suggest that the vitamin B12 (B12 transport system can be used for the cellular delivery of B12-conjugated drugs, also in long-term treatment Whether this strategy will affect the endogenous metabolism of B12 is not known. To study the effect of treatment with excess B12 or an inert derivative, we established a mouse model using implanted osmotic minipumps to deliver saline, cobinamide (Cbi (4.25 nmol/h, or B12 (1.75 nmol/h for 27 days (n = 7 in each group. B12 content and markers of B12 metabolism were analysed in plasma, urine, kidney, liver, and salivary glands. Both Cbi and B12 treatment saturated the transcobalamin protein in mouse plasma. Cbi decreased the content of B12 in tissues to 33-50% of the level in control animals but did not influence any of the markers examined. B12 treatment increased the tissue B12 level up to 350%. In addition, the transcript levels for methylenetetrahydrofolate reductase in kidneys and for transcobalamin and transcobalamin receptor in the salivary glands were reduced. Our study confirms the feasibility of delivering drugs through the B12 transport system but emphasises that B12 status should be monitored because there is a risk of decreasing the transport of endogenous B12. This risk may lead to B12 deficiency during prolonged treatment.

  5. Dietary sources of vitamin B-12 and their association with vitamin B-12 status markers in healthy older adults in the B-PROOF study

    NARCIS (Netherlands)

    E.M. Brouwer-Brolsma (Elske); R.A.M. Dhonukshe-Rutten (Rosalie); J.P. van Wijngaarden (Janneke); N.L. van der Zwaluw (N.); N. van der Velde (Nathalie); L.C.P.G.M. de Groot (Lisette)

    2015-01-01

    textabstractLow vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations

  6. Dietary sources of vitamin B-12 and their association with vitamin B-12 status markers in healthy older adults in the B-PROOF study

    NARCIS (Netherlands)

    Brouwer-Brolsma, E.M.; Dhonukshe-Rutten, R.A.M.; Wijngaarden, van J.P.; Zwaluw, van der N.L.; Velde, van der N.; Groot, de C.P.G.M.

    2015-01-01

    Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between

  7. Anaerobic biosynthesis of the lower ligand of vitamin B12.

    Science.gov (United States)

    Hazra, Amrita B; Han, Andrew W; Mehta, Angad P; Mok, Kenny C; Osadchiy, Vadim; Begley, Tadhg P; Taga, Michiko E

    2015-08-25

    Vitamin B12 (cobalamin) is required by humans and other organisms for diverse metabolic processes, although only a subset of prokaryotes is capable of synthesizing B12 and other cobamide cofactors. The complete aerobic and anaerobic pathways for the de novo biosynthesis of B12 are known, with the exception of the steps leading to the anaerobic biosynthesis of the lower ligand, 5,6-dimethylbenzimidazole (DMB). Here, we report the identification and characterization of the complete pathway for anaerobic DMB biosynthesis. This pathway, identified in the obligate anaerobic bacterium Eubacterium limosum, is composed of five previously uncharacterized genes, bzaABCDE, that together direct DMB production when expressed in anaerobically cultured Escherichia coli. Expression of different combinations of the bza genes revealed that 5-hydroxybenzimidazole, 5-methoxybenzimidazole, and 5-methoxy-6-methylbenzimidazole, all of which are lower ligands of cobamides produced by other organisms, are intermediates in the pathway. The bza gene content of several bacterial and archaeal genomes is consistent with experimentally determined structures of the benzimidazoles produced by these organisms, indicating that these genes can be used to predict cobamide structure. The identification of the bza genes thus represents the last remaining unknown component of the biosynthetic pathway for not only B12 itself, but also for three other cobamide lower ligands whose biosynthesis was previously unknown. Given the importance of cobamides in environmental, industrial, and human-associated microbial metabolism, the ability to predict cobamide structure may lead to an improved ability to understand and manipulate microbial metabolism.

  8. Considering the case for vitamin B12 fortification of flour

    Science.gov (United States)

    Reasons to fortify flour with vitamin B12 are considered, which include the high prevalence of depletion and deficiency of this vitamin that occurs in persons of all ages in resource-poor countries and in elderly in wealthier countries, as well as the adverse functional consequences of poor vitamin ...

  9. [Psychiatric manifestations of vitamin B12 deficiency: a case report].

    Science.gov (United States)

    Durand, C; Mary, S; Brazo, P; Dollfus, S

    2003-01-01

    Psychiatric manifestations are frequently associated with pernicious anemia including depression, mania, psychosis, dementia. We report a case of a patient with vitamin B12 deficiency, who has presented severe depression with delusion and Capgras' syndrome, delusion with lability of mood and hypomania successively, during a period of two Months. Case report - Mme V., a 64-Year-old woman, was admitted to the hospital because of confusion. She had no history of psychiatric problems. She had history of diabetes, hypertension and femoral prosthesis. The red blood count revealed a normocytosis with anemia (hemoglobin=11,4 g/dl). At admission she was uncooperative, disoriented in time and presented memory and attention impairment and sleep disorders. She seemed sad and older than her real age. Facial expression and spontaneous movements were reduced, her speech and movements were very slow. She had depressed mood, guilt complex, incurability and devaluation impressions. She had a Capgras' syndrome and delusion of persecution. Her neurologic examination, cerebral scanner and EEG were postponed because of uncooperation. Further investigations confirmed anemia (hemoglobin=11,4 g/dl) and revealed vitamin B12 deficiency (52 pmol/l) and normal folate level. Antibodies to parietal cells were positive in the serum and antibodies to intrinsic factor were negative. An iron deficiency was associated (serum iron=7 micromol/l; serum ferritin concentration=24 mg/l; serum transferrin concentration=3,16 g/l). This association explained normocytocis anemia. Thyroid function, hepatic and renal tests, glycemia, TP, TCA, VS, VDRL-TPHA were normal. Vitamin B12 replacement therapy was started with hydroxycobalamin 1 000 ng/day im for 10 days and iron replacement therapy. Her mental state improved dramatically within a few days. After one week of treatment the only remaining symptoms were lability of mood, delusion of persecution, Capgras' syndrome but disappeared totally 9 days after the

  10. Vitamin B-12 and Depression: Are They Related?

    Science.gov (United States)

    ... 143. Lang UE, et al. Nutritional aspects of depression. Cellular Physiology and Biochemistry. 2015;37:1029. Vitamin B12. Natural Medicines. https://naturalmedicines.therapeuticresearch.com. Accessed Oct. 18, 2016. Mikkelsen K, ... in depression. Current Medicinal Chemistry. 2016;23:1. Nov. 23, ...

  11. Vitamin B-12 and folate deficiency in chronic heart failure

    NARCIS (Netherlands)

    van der Wal, Haye H.; Comin-Colet, Josep; Klip, Ijsbrand T.; Enjuanes, Cristina; Grote Beverborg, Niels; Voors, Adriaan A.; Banasiak, Waldemar; van Veldhuisen, Dirk J.; Bruguera, Jordi; Ponikowski, Piotr; Jankowska, Ewa A.; van der Meer, Peter

    2015-01-01

    Objective To determine the prevalence, clinical correlates and the effects on outcome of vitamin B-12 and folic acid levels in patients with chronic heart failure (HF). Methods We studied an international pooled cohort comprising 610 patients with chronic HF. The main outcome measure was all-cause m

  12. Neuroenhancement with Vitamin B12—Underestimated Neurological Significance

    Directory of Open Access Journals (Sweden)

    Uwe Gröber

    2013-12-01

    Full Text Available Vitamin B12 is a cofactor of methionine synthase in the synthesis of methionine, the precursor of the universal methyl donor S-Adenosylmethionine (SAMe, which is involved in different epigenomic regulatory mechanisms and especially in brain development. A Vitamin B12 deficiency expresses itself by a wide variety of neurological manifestations such as paraesthesias, skin numbness, coordination disorders and reduced nerve conduction velocity. In elderly people, a latent Vitamin B12 deficiency can be associated with a progressive brain atrophy. Moderately elevated concentrations of homocysteine (>10 µmol/L have been associated with an increased risk of dementia, notably Alzheimer’s disease, in many cross-sectional and prospective studies. Raised plasma concentrations of homocysteine is also associated with both regional and whole brain atrophy, not only in Alzheimer’s disease but also in healthy elderly people. Clinician awareness should be raised to accurately diagnose and treat early Vitamin B12 deficiency to prevent irreversible structural brain damage.

  13. The Technological Progress of Vitamin B12%维生素B12的技术进展

    Institute of Scientific and Technical Information of China (English)

    谢丽华

    2011-01-01

    维生素B12是人和动物体内重要的水溶性维生素之一.综述了维生素B12的性质、合成及生产情况.工业生产中,脱氮假单胞杆菌和费氏丙酸杆菌是主要的生产菌种,有厌氧和好氧2种生产工艺.今后应培养高产菌株,改进发酵工艺.

  14. Detection of Chlorobenzene in Vitamin B12%维生素B12中氯苯检测

    Institute of Scientific and Technical Information of China (English)

    陈永源; 王媛

    2011-01-01

    随着欧美各国对药品中残留溶剂控制要求的提高,维生素B12在欧洲申请市场准入时需提交氯苯检测结果.实验参照"EP6.0版中2.4.24残留溶剂的鉴别和控制"内容而制定,专门用于维生素B12中氯苯含量的检测.

  15. The prevalence of cobalamin deficiency among vegetarians assessed by serum vitamin B12: a review of literature.

    Science.gov (United States)

    Pawlak, R; Lester, S E; Babatunde, T

    2014-05-01

    Individuals following vegetarian diets are at risk for developing vitamin B12 deficiency owing to suboptimal intake. As vitamin B12 is essential for the synthesis of nucleic acids, erythrocytes and in the maintenance of myelin, deficiency may result in a variety of symptoms. Some of these symptoms may be severe while others may be irreversible. The objective of this review was to assess vitamin B12 deficiency, based on reported serum vitamin B12, among individuals adhering to different types of vegetarian diets. A systematic literature search was carried out using multiple search engines including PubMed, Medline, CINAHL plus, ERIC, Nursing and Allied Health Collection and Nursing/Academic Edition. The inclusion criteria consisted of original studies that assessed serum vitamin B12, studies written in English, non-case studies and studies that reported actual percentages of vitamin B12 deficiency. Forty research studies were included. The deficiency prevalence among infants reached 45%. The deficiency among the children and adolescents ranged from 0 to 33.3%. Deficiency among pregnant women ranged from 17 to 39%, dependent on the trimester. Adults and elderly individuals had a deficiency range of 0-86.5%. Higher deficiency prevalence was reported in vegans than in other vegetarians. Thus, with few exceptions, the reviewed studies documented relatively high deficiency prevalence among vegetarians. Vegans who do not ingest vitamin B12 supplements were found to be at especially high risk. Vegetarians, especially vegans, should give strong consideration to the use of vitamin B12 supplements to ensure adequate vitamin B12 intake. Vegetarians, regardless of the type of vegetarian diet they adhere to, should be screened for vitamin B12 deficiency.

  16. Vegetarer har høj risiko for at få B12-vitaminmangel

    DEFF Research Database (Denmark)

    Javid, Parva; Christensen, Erik

    2016-01-01

    Since vegetarians have a lower intake of vitamin B12 (B12) than non-vegetarians, they are at increased risk of developing B12 deficiency. The less animal products the food contains the worse the B12 status. However, even lacto-ovo-vegetarians run the risk of becoming deficient in B12. Vegetarians...... are recommended regularly to take supplements of B12, and they should be informed of the lacking content of B12 of plant products and the hazards of B12 deficiency. Furthermore, vegetarians should routinely be checked for possible B12 deficiency....

  17. Novel carbon dioxide gas sensor based on infrared absorption

    Science.gov (United States)

    Zhang, Guangjun; Lui, Junfang; Yuan, Mei

    2000-08-01

    The feasibility of sensing carbon dioxide with a IR single- beam optical structure is studied, and a novel carbon dioxide gas sensor based on IR absorption is achieved. Applying the Lambert-Beer law and some key techniques such as current stabilization for IR source, using a high-quality IR detector, and data compensation for the influences of ambience temperature and atmosphere total pressure, the sensor can measure carbon dioxide with high precision and efficiency. The mathematical models for providing temperature and pressure compensation for the sensor are established. Moreover the solutions to the models are proposed. Both the models and the solutions to the models are verified via experiments. The sensor possesses the advantages of small volume, light weight, low power consumption, and high reliability. Therefore it can be used in many associated fields, such as environmental protection, processing control, chemical analysis, medical diagnosis, and space environmental and control systems.

  18. All-optical reservoir computer based on saturation of absorption.

    Science.gov (United States)

    Dejonckheere, Antoine; Duport, François; Smerieri, Anteo; Fang, Li; Oudar, Jean-Louis; Haelterman, Marc; Massar, Serge

    2014-05-05

    Reservoir computing is a new bio-inspired computation paradigm. It exploits a dynamical system driven by a time-dependent input to carry out computation. For efficient information processing, only a few parameters of the reservoir needs to be tuned, which makes it a promising framework for hardware implementation. Recently, electronic, opto-electronic and all-optical experimental reservoir computers were reported. In those implementations, the nonlinear response of the reservoir is provided by active devices such as optoelectronic modulators or optical amplifiers. By contrast, we propose here the first reservoir computer based on a fully passive nonlinearity, namely the saturable absorption of a semiconductor mirror. Our experimental setup constitutes an important step towards the development of ultrafast low-consumption analog computers.

  19. 4-ethylphenyl-cobalamin impairs tissue uptake of vitamin B12 and causes vitamin B12 deficiency in mice

    DEFF Research Database (Denmark)

    Mutti, Elena; Ruetz, Markus; Birn, Henrik

    2013-01-01

    Coβ-4-ethylphenyl-cob(III) alamin (EtPhCbl) is an organometallic analogue of vitamin B12 (CNCbl) which binds to transcobalamin (TC), a plasma protein that facilitates the cellular uptake of cobalamin (Cbl). In vitro assays with key enzymes do not convert EtPhCbl to the active coenzyme forms of Cb...

  20. Folate–vitamin B-12 interaction in relation to cognitive impairment, anemia, and biochemical indicators of vitamin B-12 deficiency

    Science.gov (United States)

    Previous reports on pernicious anemia treatment suggested that high folic acid intake adversely influences the natural history of vitamin B-12 deficiency, which affects many elderly individuals. However, experimental investigation of this hypothesis is unethical, and the few existing observational d...

  1. HAB detection based on absorption and backscattering properties of phytoplankton

    Science.gov (United States)

    Lei, Hui; Pan, Delu; Bai, Yan; Chen, Xiaoyan; Zhou, Yan; Zhu, Qiankun

    2011-11-01

    The coastal area of East China Sea (ECS) suffers from the harmful algal blooms (HAB) frequently every year in the warm season. The most common causative phytoplankton algal species of HAB in the ECS in recent years are Prorocentrum donghaiense (dinoflagellates), Karenia mikimotoi (dinoflagellates which could produce hemolytic and ichthyotoxins) and Skeletonema costatum (diatom). The discrimination between the dinoflagellates and diatom HAB through ocean color remote sensing approach can add the knowledge of HAB events in ECS and help to the precaution. A series of in-situ measurement consisted of absorption coefficient, total scattering and particulate backscattering coefficient was conducted in the southern coast of Zhejiang Province in May 2009, and the estuary of Changjiang River in August 2009 and December 2010, which encountered two HAB events and a moderate bloom. The Inherent Optical Properties (IOPs) of the bloom waters have significant difference between phytoplankton species in absorption and backscattering properties. The chlorophyll a specific absorption coefficient (a*phy(λ)) for the bloom patches (chlorophyll a concentration >6mg m-3) differ greatly from the adjacent normal seawater, with the a*phy(λ) of bloom water lower than 0.03 m2 mg-1 while the a*phy(λ) of the adjacent normal seawater is much higher (even up to 0.06 m2 mg-1). Meanwhile, the backscattering coefficients at 6 wavebands (420, 442, 470, 510, 590 and 700nm) are also remarkably lower for bloom waters ( 0.02 m-1). The backscattering coefficient ratio (Rbp(λ)) is much lower for diatom bloom waters than for dinoflagellates types (0.01079 vs. 0.01227). A discrimination model based on IOPs is established, and several typical dinoflagellates and diatom bloom events including Prorocentrum donghaiense, Karenia mikimotoi and Skeletonema costatum in the ECS are picked out for testing with the MODIS-L2 and L3 ocean color remote sensing products from NASA website. The result proves that the

  2. Development of a two-step cultivation strategy for the production of vitamin B12 by Bacillus megaterium.

    Science.gov (United States)

    Mohammed, Yousef; Lee, Byong; Kang, Zhen; Du, Guocheng

    2014-07-15

    Vitamin B12 is a fascinating molecule which acts as a co-factor in the metabolism of many organisms, especially affecting DNA synthesis and regulation, fatty acid synthesis and energy production. The synthesis of vitamin B12 is limited to a few of bacteria and archaea. Therefore, industrial microbial fermentation is used to meet annual demands worldwide of vitamin B12 and as an alternative method to the chemical synthesis which requires at least 60 steps that is uneconomical. Bacillus megaterium is one of vitamin B12 producers and an ideal host for many biotechnology applications and being one of the best tools for the industrial production of several enzymes. Therefore, a two-step optimization strategy was established to produce high yield of vitamin B12 by B. megaterium through the provision of the production requirements and the suitable conditions for the biosynthesis of vitamin B12. We achieved the optimum conditions for the fermentation process of B. megaterium to produce high yield of vitamin B12 in a practical way based on statistical design and analysis which allowed vitamin B12 production to increase up to 759-fold (204.46 μg/l) as compared with control without parameters (0.26 μg/L). High performance liquid chromatography coupled to variable wavelength detector and mass spectrometry has been used to identify vitamin B12 forms and confirm the results. We developed the fermentation process of B. megaterium to enhance the production of vitamin B12 by providing the required supplements for the synthesis of vitamin B12 (CoCl2, δ-aminolevulinic acid (ALA) and 5,6-dimethylbenzimidazole (DMB)) and dividing the fermentation process into three stages. In addition, the optimum incubation times of the three fermentation stages were investigated and performed with reducing number of experimental and evaluated multiple parameters and their interactions by using statistical experimental design and analysis. All of these strategies has proven successful in

  3. Protective effects of vitamin B12, ginseng saponin, and folic acid against murine fetal deformities caused by hyperthermia

    Institute of Scientific and Technical Information of China (English)

    李荷莲; 王博蔚; 赵丹; 韩丽英

    2003-01-01

    Objective To investigate the protective effects of vitamin B12, ginseng saponin, and folic acid on mouse embryos subjected to high heat.Methods Mice were used for the experiment.Results After exposure of pregnant mice to high heat, the rates of teratism, stillbirth, and fetal absorption were markedly lower in mice treated with ginseng saponin and folic acid following heat exposure than in untreated mice. There were no significant differences in these rates when comparing mice treated with vitamin B12 with the untreated mice.Conclusions Ginseng saponin and folic acid can lessen injuries to murine embryos caused by high heat, while vitamin B12 has little protective effect against high temperature except for promoting overall embryonic growth.

  4. The high-pressure compressibility of B12P2

    Science.gov (United States)

    Gao, Yang; Zhou, Mi; Wang, Haiyan; Ji, Cheng; Whiteley, C. E.; Edgar, J. H.; Liu, Haozhe; Ma, Yanzhang

    2017-03-01

    In situ high pressure synchrotron X-ray diffraction measurements were performed on icosahedral boron phosphide (B12P2) to 43.2 GPa. No structural phase transition occurs over this pressure range. The bulk modulus of B12P2 is KOT = 207 ± 7 GPa with pressure derivative of K'OT = 6.6 ± 0.8 . The structure is most compressible along the chain formed by phosphorus and boron atoms in the crystal structure. It is believed that the compressibility of boron-rich compounds at close to ambient pressure is determined by the boron icosahedral structure, while the inclusive atoms (both boron and non-boron) between the icosahedra determine the high-pressure compressibility and structure stability.

  5. Vitamin B12 deficiency presenting as acute ataxia.

    Science.gov (United States)

    Crawford, John Ross; Say, Daphne

    2013-03-26

    A previously healthy 7-year-old Caucasian boy was hospitalised for evaluation of acute ataxia and failure to thrive, initially suspicious for an intracranial mass. Weight and body mass index were below the third percentile and he demonstrated loss of joint position and vibratory sense on examination. Laboratory studies revealed megaloblastic anaemia while an initial MRI of the brain showed no evidence of mass lesions or other abnormalities. A dietary history revealed the child subscribed to a restrictive vegan diet with little to no intake of animal products or other fortified foods. The child was diagnosed with presumed vitamin B12 deficiency and was treated with intramuscular B12 injections. Neurological symptoms resolved promptly within several days after starting therapy. This case underlines the importance of assessing nutritional status in the evaluation of neurological dysfunction in the pediatric patient.

  6. Synthesis and Absorption Properties of Calix[6]amides-based Polymers

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Reacting calix[6]arene hexaesters with poly(ethyleneimine), a series of calix [6]amides- based polymers were obtained for the first time.It is found that they show high absorption capacities towards soft cations comparing to hard cations, and the absorption abilities enhanced with the increasing of calixarene content, which may indicates the cavity of calixarene plays crucial role in absorption.Polymer 2c shows good selective absorption capability towards Ag+ among the tested cations.

  7. LACK OF VITAMIN B12 AFTER ROUX Y GASTRIC BYPASS

    OpenAIRE

    Reginaldo, Greise Janaina; Silva, Alice Freitas da

    2014-01-01

    Obesity is a public health issue, with several factors as its cause. It may be related to several co-morbidities such as diabetes mellitus II, systemic arterial pressure, dyslipidemia, cancer and others. Current research verified aspects of bariatric surgery with special focus on alterations caused by the lack of vitamin B12. The bibliographical review evaluated scientific papers, particularly recent ones, to obtain data on the theme. Obesity is defined as a disease characterized by the accum...

  8. LACK OF VITAMIN B12 AFTER ROUX Y GASTRIC BYPASS

    OpenAIRE

    Reginaldo, Greise Janaina; Silva, Alice Freitas da

    2014-01-01

    Obesity is a public health issue, with several factors as its cause. It may be related to several co-morbidities such as diabetes mellitus II, systemic arterial pressure, dyslipidemia, cancer and others. Current research verified aspects of bariatric surgery with special focus on alterations caused by the lack of vitamin B12. The bibliographical review evaluated scientific papers, particularly recent ones, to obtain data on the theme. Obesity is defined as a disease characterized by the accum...

  9. Folatos y vitamina B12 en la salud humana

    OpenAIRE

    Brito,Alex; HERTRAMPF,EVA; Olivares,Manuel; Gaitán,Diego; Sánchez, Hugo; Allen, Lindsay H.; Uauy, Ricardo

    2012-01-01

    During the past decade the role of folate and vitamin B12 in human nutrition have been under constant re-examination. Basic knowledge on the metabolism and interactions between these essential nutrients has expanded and multiple complexities have been unraveled. These micronutrients have shared functions and intertwined metabolic pathways that define the size of the "methyl donor" pool utilized in multiple metabolic pathways; these include DNA methylation and synthesis of nucleic acids. In Ch...

  10. White Centered Retinal Hemorrhages in Vitamin B12 Deficiency Anemia

    Directory of Open Access Journals (Sweden)

    Claus Zehetner

    2011-05-01

    Full Text Available Background: To report a case of severe vitamin B12 deficiency anemia presenting with white centered retinal hemorrhages. Methods: Interventional case report. Results: A 40-year-old man, general practitioner himself, presented with a 1-day history of diminished left visual acuity and a drop-shaped central scotoma. The corrected visual acuities were 20/20, OD and 20/100, OS. Ophthalmic examination revealed bilaterally pale tarsal conjunctiva, discretely icteric bulbar conjunctiva and disseminated white centered intraretinal hemorrhages with foveal involvement. OCT imaging through these lesions revealed a retinal thickening caused by a sub-ILM accumulation of hyperreflective and inhomogeneous deposits within the nerve fiber layer. Immediate laboratory work-up showed severe megaloblastic anemia caused by vitamin B12 deficiency requiring erythrocyte transfusions. Discussion: Most reports of white centered retinal hemorrhages have been described in patients with leukemic retinopathy and bacterial endocarditis. It is interesting that this case of vitamin B12 deficiency anemia retinopathy has a clinically indistinguishable fundus appearance. This is probably due to the common pathology of capillary disruption and subsequent hemostatic fibrin plug formation. In megaloblastic anemia, direct anoxia results in endothelial dysfunction. The loss of impermeability allows extrusion of whole blood and subsequent diffusion from the disrupted site throughout and above the nerve fiber layer. Therefore the biomicroscopic pattern of white centered hemorrhages observed in anemic retinopathy is most likely due to the clot formation as the reparative sequence after capillary rupture.

  11. Interventions with vitamins B6, B12 and C in pregnancy.

    Science.gov (United States)

    Dror, Daphna K; Allen, Lindsay H

    2012-07-01

    The water-soluble vitamins B6, B12 and C play important roles in maternal health as well as fetal development and physiology during gestation. This systematic review evaluates the risks and benefits of interventions with vitamins B6, B12 and C during pregnancy on maternal, neonatal and child health and nutrition outcomes. Relevant publications were identified by searching PubMed, Popline and Web of Science databases. Meta-analyses were conducted for outcomes where results from at least three controlled trials were available. Potential benefits of vitamin B6 supplementation were reduction in nausea and vomiting, improvement in dental health, and treatment of some cases of anaemia. In meta-analysis based on three small studies, vitamin B6 supplementation had a significant positive effect on birthweight (d = 217 g [95% confidence interval (CI) 130, 304]). Interventions with vitamin C alone or combined with vitamin E did not systematically reduce the incidence of pre-eclampsia, premature rupture of membranes, or other adverse pregnancy outcomes. In meta-analyses, vitamins C and E increased the risk of pregnancy-related hypertension (relative risk 1.10 [95% CI 1.02, 1.19]). Effects of vitamin B6 or C intervention on other neonatal outcomes, including preterm birth, low birthweight, and perinatal morbidity and mortality, were not significant. Data on child health outcomes were lacking. Despite the prevalence of vitamin B12 deficiency amongst populations with limited intake of animal source foods, no intervention trials have evaluated vitamin B12 supplementation before or during pregnancy. In conclusion, existing evidence does not justify vitamin C supplementation during pregnancy. Additional studies are needed to confirm positive effects of vitamin B6 supplementation on infant birthweight and other outcomes. While vitamin B12 supplementation may reduce the incidence of neural tube defects in the offspring based on theoretical considerations, research is needed to support

  12. Models of ionospheric VLF absorption of powerful ground based transmitters

    Science.gov (United States)

    Cohen, M. B.; Lehtinen, N. G.; Inan, U. S.

    2012-12-01

    Ground based Very Low Frequency (VLF, 3-30 kHz) radio transmitters play a role in precipitation of energetic Van Allen electrons. Initial analyses of the contribution of VLF transmitters to radiation belt losses were based on early models of trans-ionospheric propagation known as the Helliwell absorption curves, but some recent studies have found that the model overestimates (by 20-100 dB) the VLF energy reaching the magnetosphere. It was subsequently suggested that conversion of wave energy into electrostatic modes may be responsible for the error. We utilize a newly available extensive record of VLF transmitter energy reaching the magnetosphere, taken from the DEMETER satellite, and perform a direct comparison with a sophisticated full wave model of trans-ionospheric propagation. Although the model does not include the effect of ionospheric irregularities, it correctly predicts the average total power injected into the magnetosphere within several dB. The results, particularly at nighttime, appear to be robust against the variability of the ionospheric electron density. We conclude that the global effect of irregularity scattering on whistler mode conversion to quasi-electrostatic may be no larger than 6 dB.

  13. A vitamin B-12 supplement of 500 μg/d for eight weeks does not normalize urinary methylmalonic acid or other biomarkers of vitamin B-12 status in elderly people with moderately poor vitamin B-12 status.

    Science.gov (United States)

    Hill, Marilyn H; Flatley, Janet E; Barker, Margo E; Garner, Clare M; Manning, Nigel J; Olpin, Simon E; Moat, Stuart J; Russell, Jean; Powers, Hilary J

    2013-02-01

    Plasma vitamin B-12 is the most commonly used biomarker of vitamin B-12 status, but the predictive value for low vitamin B-12 status is poor. The urinary methylmalonic acid (uMMA) concentration has potential as a functional biomarker of vitamin B-12 status, but the response to supplemental vitamin B-12 is uncertain. A study was conducted to investigate the responsiveness of uMMA to supplemental vitamin B-12 in comparison with other biomarkers of vitamin B-12 status [plasma vitamin B-12, serum holotranscobalamin (holoTC), plasma MMA] in elderly people with moderately poor vitamin B-12 status. A double-blind, placebo-controlled, randomized 8-wk intervention study was carried out using vitamin B-12 supplements (500 μg/d, 100 μg/d, and 10 μg/d cyanocobalamin) in 100 elderly people with a combined plasma vitamin B-12 1.5. All biomarkers had a dose response to supplemental vitamin B-12. Improvements in plasma vitamin B-12 and serum holoTC were achieved at cobalamin supplements of 10 μg/d, but even 500 μg/d for 8 wk did not normalize plasma vitamin B-12 in 8% and serum holoTC in 12% of people. The response in uMMA was comparable with plasma MMA; 15-25% of people still showed evidence of metabolic deficiency after 500 μg/d cobalamin for 8 wk. There was a differential response in urinary and plasma MMA according to smoking behavior; the response was enhanced in ex-smokers compared with never-smokers. uMMA offers an alternative marker of metabolic vitamin-B12 status, obviating the need for blood sampling.

  14. Dietary Sources of Vitamin B-12 and Their Association with Vitamin B-12 Status Markers in Healthy Older Adults in the B-PROOF Study

    Science.gov (United States)

    Brouwer-Brolsma, Elske M.; Dhonukshe-Rutten, Rosalie A. M.; van Wijngaarden, Janneke P.; van der Zwaluw, Nikita L.; van der Velde, Nathalie; de Groot, Lisette C. P. G. M.

    2015-01-01

    Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between dietary sources of vitamin B-12 (meat, fish and shellfish, eggs, dairy) and serum vitamin B-12, using cross-sectional data of 600 Dutch community-dwelling adults (≥65 years). Dietary intake was assessed with a validated food frequency questionnaire. Vitamin B-12 concentrations were measured in serum. Associations were studied over tertiles of vitamin B-12 intake using P for trend, by calculating prevalence ratios (PRs), and splines. Whereas men had significantly higher vitamin B-12 intakes than women (median (25th–75th percentile): 4.18 (3.29–5.38) versus 3.47 (2.64–4.40) μg/day), serum vitamin B-12 did not differ between the two sexes (mean ± standard deviation (SD): 275 ± 104 pmol/L versus 290 ± 113 pmol/L). Higher intakes of dairy, meat, and fish and shellfish were significantly associated with higher serum vitamin B-12 concentrations, where meat and dairy—predominantly milk were the most potent sources. Egg intake did not significantly contribute to higher serum vitamin B-12 concentrations. Thus, dairy and meat were the most important contributors to serum vitamin B-12, followed by fish and shellfish. PMID:26389945

  15. Dietary Sources of Vitamin B-12 and Their Association with Vitamin B-12 Status Markers in Healthy Older Adults in the B-PROOF Study

    Directory of Open Access Journals (Sweden)

    Elske M. Brouwer-Brolsma

    2015-09-01

    Full Text Available Low vitamin B-12 concentrations are frequently observed among older adults. Malabsorption is hypothesized to be an important cause of vitamin B-12 inadequacy, but serum vitamin B-12 may also be differently affected by vitamin B-12 intake depending on food source. We examined associations between dietary sources of vitamin B-12 (meat, fish and shellfish, eggs, dairy and serum vitamin B-12, using cross-sectional data of 600 Dutch community-dwelling adults (≥65 years. Dietary intake was assessed with a validated food frequency questionnaire. Vitamin B-12 concentrations were measured in serum. Associations were studied over tertiles of vitamin B-12 intake using P for trend, by calculating prevalence ratios (PRs, and splines. Whereas men had significantly higher vitamin B-12 intakes than women (median (25th–75th percentile: 4.18 (3.29–5.38 versus 3.47 (2.64–4.40 μg/day, serum vitamin B-12 did not differ between the two sexes (mean ± standard deviation (SD: 275 ± 104 pmol/L versus 290 ± 113 pmol/L. Higher intakes of dairy, meat, and fish and shellfish were significantly associated with higher serum vitamin B-12 concentrations, where meat and dairy—predominantly milk were the most potent sources. Egg intake did not significantly contribute to higher serum vitamin B-12 concentrations. Thus, dairy and meat were the most important contributors to serum vitamin B-12, followed by fish and shellfish.

  16. Two-and three-photon absorption in a novel fluorene-based compound

    Institute of Scientific and Technical Information of China (English)

    Wenbo Ma; Yiqun Wu; Donghong Gu; Fuxi Gan

    2005-01-01

    @@ A novel symmetrical charge transfer fluorene-based compound 2,7-bis (4-methoxystyryl)-9, 9-bis (2-ethylhexyl)-9H-fluorene (abbreviated as BMOSF) was synthesized and its nonlinear absorption was investigated using two different laser systems: a 140-fs, 800-nm Ti:sapphire laser operating at 1-kHz repetition rate and a 38-ps, 1064-nm Nd:YAG pulsed laser operating at 10-Hz repetition rate, respectively. Unique nonlinear absorption properties in this new compound were observed that rise from multiphoton absorption. The nonlinear absorption coefficients were measured to be 6.02 × 10-3 cm/GW (due to two-photon absorption, exciting wavelength is 800 nm) and 3.6×10-20 cm3/W2 (due to three-photon absorption, exciting wavelength is 1064 nm). This new compound possesses strong fluorescence induced by two-photon absorption and obvious three-photon absorption optical limiting effects.

  17. Preparation and Characterization of Cyanocobalamin (Vit B12 Microemulsion Properties and Structure for Topical and Transdermal Application

    Directory of Open Access Journals (Sweden)

    Anayatollah Salimi

    2013-07-01

    This study showed that both microemulsions provided good solubility of Vit B12 with a wide range of internal structure. Low water solubilization capacity is a common property of microemulsions that can affect drug release and permeability through the skin. Based on Vit B12 properties, specially, intermediate oil and water solubility, better drug partitioning into the skin may be obtained by traditional formulations with wide range of structure and high amount of free and bounded water.

  18. Response to vitamin B12 and folic acid in myalgic encephalomyelitis and fibromyalgia.

    Directory of Open Access Journals (Sweden)

    Björn Regland

    Full Text Available Patients with myalgic encephalomyelitis (ME, also called chronic fatigue syndrome may respond most favorably to frequent vitamin B12 injections, in vital combination with oral folic acid. However, there is no established algorithm for individualized optimal dosages, and rate of improvement may differ considerably between responders.To evaluate clinical data from patients with ME, with or without fibromyalgia, who had been on B12 injections at least once a week for six months and up to several years.38 patients were included in a cross-sectional survey. Based on a validated observer's rating scale, they were divided into Good (n = 15 and Mild (n = 23 responders, and the two groups were compared from various clinical aspects.Good responders had used significantly more frequent injections (p<0.03 and higher doses of B12 (p<0.03 for a longer time (p<0.0005, higher daily amounts of oral folic acid (p<0.003 in good relation with the individual MTHFR genotype, more often thyroid hormones (p<0.02, and no strong analgesics at all, while 70% of Mild responders (p<0.0005 used analgesics such as opioids, duloxetine or pregabalin on a daily basis. In addition to ME, the higher number of patients with fibromyalgia among Mild responders was bordering on significance (p<0.09. Good responders rated themselves as "very much" or "much" improved, while Mild responders rated "much" or "minimally" improved.Dose-response relationship and long-lasting effects of B12/folic acid support a true positive response in the studied group of patients with ME/fibromyalgia. It's important to be alert on co-existing thyroid dysfunction, and we suspect a risk of counteracting interference between B12/folic acid and certain opioid analgesics and other drugs that have to be demethylated as part of their metabolism. These issues should be considered when controlled trials for ME and fibromyalgia are to be designed.

  19. UV absorption and scattering properties of inorganic-based sunscreens.

    Science.gov (United States)

    Egerton, Terry A; Tooley, Ian R

    2012-04-01

    This article first introduces the concepts that underlie the calculations of scattering and absorption of light by small particles. Results of Mie theory calculations of light scattering and light absorption by 20, 50 and 100 nm TiO₂ and ZnO particles are then presented. As the attenuation, or extinction, by these particles is the sum of the scattering and absorption, the attenuation can then be calculated for wavelengths over the UVA and UVB region. These theoretical results are then shown to be in reasonable agreement with experimental results for alkyl benzoate dispersions of three different types of TiO₂ particle whose mean sizes range from 35 to 145 nm. Finally, the link between these measurements and the absorption curves of formulated dispersions of sunscreens are demonstrated and related to in vitro SPF and UVAPF measurements.

  20. Association between vitamin B12 intake and EURRECA’s prioritized biomarkers of vitamin B12 in young populations: a systematic review

    NARCIS (Netherlands)

    Iglesia, I.; Dhonukshe-Rutten, R.A.M.; Bel-Serrat, S.; Doets, E.L.; Cavelaars, A.J.E.M.; Veer, van 't P.; Nissenshohn, M.; Benetou, V.; Hermoso, M.; Berti, C.; Groot, de C.P.G.M.; Moreno, L.A.

    2013-01-01

    Objective To review evidence on the associations between vitamin B12 intake and its biomarkers, vitamin B12 intake and its functional health outcomes, and vitamin B12 biomarkers and functional health outcomes. Design A systematic review was conducted by searching electronic databases, until January

  1. Systematic review on daily vitamin B12 losses and bioavailability for deriving recommendations on vitamin B12 intake with the factorial approach

    NARCIS (Netherlands)

    Doets, E.L.; Veld, in 't P.H.; Szczecinska, A.; Dhonukshe-Rutten, R.A.M.; Cavelaars, A.J.E.M.; Veer, van 't P.; Brzozowska, A.M.; Groot, de C.P.G.M.

    2013-01-01

    Aims: To systematically review the literature on daily losses and bioavailability of vitamin B12. These estimates could be used for deriving recommendations on vitamin B12 intake for adults and elderly. Methods: We identified publications on daily vitamin B12 losses (July 2011) and publications on t

  2. Systematic review on daily vitamin B12 losses and bioavailability for deriving recommendations on vitamin B12 intake with the factorial approach

    NARCIS (Netherlands)

    Doets, E.L.; Veld, in 't P.H.; Szczecinska, A.; Dhonukshe-Rutten, R.A.M.; Cavelaars, A.J.E.M.; Veer, van 't P.; Brzozowska, A.M.; Groot, de C.P.G.M.

    2013-01-01

    Aims: To systematically review the literature on daily losses and bioavailability of vitamin B12. These estimates could be used for deriving recommendations on vitamin B12 intake for adults and elderly. Methods: We identified publications on daily vitamin B12 losses (July 2011) and publications on t

  3. Systematic review on daily vitamin B12 losses and bioavailability for deriving recommendations on vitamin B12 intake with the factorial approach

    NARCIS (Netherlands)

    Doets, E.L.; Veld, in 't P.H.; Szczecinska, A.; Dhonukshe-Rutten, R.A.M.; Cavelaars, A.J.E.M.; Veer, van 't P.; Brzozowska, A.M.; Groot, de C.P.G.M.

    2013-01-01

    Aims: To systematically review the literature on daily losses and bioavailability of vitamin B12. These estimates could be used for deriving recommendations on vitamin B12 intake for adults and elderly. Methods: We identified publications on daily vitamin B12 losses (July 2011) and publications on

  4. Association between vitamin B12 intake and EURRECA’s prioritized biomarkers of vitamin B12 in young populations: a systematic review

    NARCIS (Netherlands)

    Iglesia, I.; Dhonukshe-Rutten, R.A.M.; Bel-Serrat, S.; Doets, E.L.; Cavelaars, A.J.E.M.; Veer, van 't P.; Nissenshohn, M.; Benetou, V.; Hermoso, M.; Berti, C.; Groot, de C.P.G.M.; Moreno, L.A.

    2013-01-01

    Objective To review evidence on the associations between vitamin B12 intake and its biomarkers, vitamin B12 intake and its functional health outcomes, and vitamin B12 biomarkers and functional health outcomes. Design A systematic review was conducted by searching electronic databases, until January

  5. Vitamin B-12 supplementation during pregnancy and early lactation increases maternal, breast milk, and infant measures of vitamin B-12 status.

    Science.gov (United States)

    Duggan, Christopher; Srinivasan, Krishnamachari; Thomas, Tinku; Samuel, Tinu; Rajendran, Ramya; Muthayya, Sumithra; Finkelstein, Julia L; Lukose, Ammu; Fawzi, Wafaie; Allen, Lindsay H; Bosch, Ronald J; Kurpad, Anura V

    2014-05-01

    Pregnant women in resource-poor areas are at risk of multiple micronutrient deficiencies, and indicators of low vitamin B-12 status have been associated with adverse pregnancy outcomes, including anemia, low birth weight, and intrauterine growth retardation. To evaluate whether daily oral vitamin B-12 supplementation during pregnancy increases maternal and infant measures of vitamin B-12 status, we performed a randomized, placebo-controlled clinical trial. Pregnant women vitamin B-12 (50 μg) or placebo through 6 wk postpartum. All women were administered iron and folic acid supplements throughout pregnancy. One hundred eighty-three women were randomly assigned to receive vitamin B-12 and 183 to receive placebo. Compared with placebo recipients, vitamin B-12-supplemented women had significantly higher plasma vitamin B-12 concentrations at both the second (median vitamin B-12 concentration: 216 vs. 111 pmol/L, P vitamin B-12 concentration was 136 pmol/L in vitamin B-12-supplemented women vs. 87 pmol/L in the placebo group (P vitamin B-12-supplemented women, the incidence of delivering an infant with intrauterine growth retardation was 33 of 131 (25%) vs. 43 of 125 (34%) in those administered placebo (P = 0.11). In a subset of infants tested at 6 wk of age, median plasma vitamin B-12 concentration was 199 pmol/L in those born to supplemented women vs. 139 pmol/L in the placebo group (P = 0.01). Infant plasma methylmalonic acid and homocysteine concentrations were significantly lower in the vitamin B-12 group as well. Oral supplementation of urban Indian women with vitamin B-12 throughout pregnancy and early lactation significantly increases vitamin B-12 status of mothers and infants. It is important to determine whether there are correlations between these findings and neurologic and metabolic functions. This trial was registered at clinicaltrials.gov as NCT00641862.

  6. Vitamin B12 intake and related biomarkers: associations in a Dutch elderly population

    NARCIS (Netherlands)

    Wijngaarden, van J.P.; Dhonukshe-Rutten, R.A.M.; Brouwer, E.M.; Enneman, A.W.; Swart, K.M.A.; Dijk, van S.C.; Veld, in 't P.H.; Schoor, van N.M.; Velde, van der N.; Jonge, de R.; Lips, P.; Uitterlinden, A.G.; Groot, de C.P.G.M.

    2017-01-01

    Background: Vitamin B12 status is measured by four plasma/serum biomarkers: total vitamin B12 (total B12), holotranscobalamin (holoTC), methylmalonic acid (MMA) and homocysteine (tHcy). Associations of B12 intake with holoTC and tHcy and associations between all four biomarkers have not been

  7. Severe but not moderate vitamin B12 deficiency impairs lipid profile, induces adiposity and leads to adverse gestational outcome in female C57BL/6 mice

    Directory of Open Access Journals (Sweden)

    Shampa eGhosh

    2016-01-01

    Full Text Available Vitamin B12 deficiency is widely prevalent in women of childbearing age especially in developing countries. In the present study, through dietary restriction, we have established mouse models of severe and moderate vitamin B12 deficiencies to elucidate the impact on body composition, biochemical parameters and reproductive performance. Female weanling C57BL/6 mice were fed for four weeks, (a control AIN-76A diet, (b vitamin B12 restricted AIN-76A diet with pectin as dietary fiber (severe deficiency group, as pectin inhibits vitamin B12 absorption or (c vitamin B12 restricted AIN-76A diet with cellulose as dietary fiber (moderate deficiency group as cellulose does not interfere with vitamin B12 absorption. After confirming deficiency, the mice were mated with male colony mice and maintained on their respective diets throughout pregnancy, lactation and thereafter till 12 weeks. Severe vitamin B12 deficiency increased body fat % significantly, induced adiposity and altered lipid profile. Pregnant dams of both the deficient groups developed anemia. Severe vitamin B12 deficiency decreased the percentage of conception and litter size, pups were small-for-gestational-age and had significantly lower body weight at birth as well as weaning. Most of the offspring born to severely deficient dams died within 24 hours of birth. Stress markers and adipocytokines were elevated in severe deficiency with concomitant decrease in antioxidant defense. The results show that severe but not moderate vitamin B12 restriction had profound impact on the physiology of C57BL/6 mice. Oxidative and corticosteroid stress, inflammation and poor antioxidant defense seem to be the probable underlying mechanisms mediating the deleterious effects.

  8. Severe but Not Moderate Vitamin B12 Deficiency Impairs Lipid Profile, Induces Adiposity, and Leads to Adverse Gestational Outcome in Female C57BL/6 Mice.

    Science.gov (United States)

    Ghosh, Shampa; Sinha, Jitendra Kumar; Putcha, Uday Kumar; Raghunath, Manchala

    2016-01-01

    Vitamin B12 deficiency is widely prevalent in women of childbearing age, especially in developing countries. In the present study, through dietary restriction, we have established mouse models of severe and moderate vitamin B12 deficiencies to elucidate the impact on body composition, biochemical parameters, and reproductive performance. Female weanling C57BL/6 mice were fed for 4 weeks: (a) control AIN-76A diet, (b) vitamin B12-restricted AIN-76A diet with pectin as dietary fiber (severe deficiency group, as pectin inhibits vitamin B12 absorption), or (c) vitamin B12-restricted AIN-76A diet with cellulose as dietary fiber (moderate deficiency group as cellulose does not interfere with vitamin B12 absorption). After confirming deficiency, the mice were mated with male colony mice and maintained on their respective diets throughout pregnancy, lactation, and thereafter till 12 weeks. Severe vitamin B12 deficiency increased body fat% significantly, induced adiposity and altered lipid profile. Pregnant dams of both the deficient groups developed anemia. Severe vitamin B12 deficiency decreased the percentage of conception and litter size, pups were small-for-gestational-age and had significantly lower body weight at birth as well as weaning. Most of the offspring born to severely deficient dams died within 24 h of birth. Stress markers and adipocytokines were elevated in severe deficiency with concomitant decrease in antioxidant defense. The results show that severe but not moderate vitamin B12 restriction had profound impact on the physiology of C57BL/6 mice. Oxidative and corticosteroid stress, inflammation and poor antioxidant defense seem to be the probable underlying mechanisms mediating the deleterious effects.

  9. New acoustical technology of sound absorption based on reverse horn

    Science.gov (United States)

    Zhang, Yong Yan; Wu, Jiu Hui; Cao, Song Hua; Cao, Pei; Zhao, Zi Ting

    2016-12-01

    In this paper, a novel reverse horn’s sound-absorption mechanism and acoustic energy focusing mechanism for low-frequency broadband are presented. Due to the alternation of the reverse horn’s thickness, the amplitude of the acoustic pressure propagated in the structure changes, which results in growing energy focused in the edge and in the reverse horn’s tip when the characteristic length is equal to or less than a wavelength and the incident wave is compressed. There are two kinds of methods adopted to realize energy dissipation. On the one hand, sound-absorbing materials are added in incident direction in order to overcome the badness of the reverse horn’s absorption in high frequency and improve the overall high-frequency and low-frequency sound-absorption coefficients; on the other hand, adding mass and film in its tip could result in mechanical energy converting into heat energy due to the coupled vibration of mass and the film. Thus, the reverse horn with film in the tip could realize better sound absorption for low-frequency broadband. These excellent properties could have potential applications in the one-dimensional absorption wedge and for the control of acoustic wave.

  10. Wideband absorption in fibonacci quasi-periodic graphene-based hyperbolic metamaterials

    Science.gov (United States)

    Ning, Renxia; Liu, Shaobin; Zhang, Haifeng; Kong, Xiangkun; Bian, Borui; Bao, Jie

    2014-12-01

    A heterostructure containing a Fibonacci quasi-periodic layer and a resonant metal back reflector is proposed, which can realize wideband absorption. The Fibonacci layer is composed of graphene-based hyperbolic metamaterials and isotropic media to obtain wideband absorption. To enhance absorption, an impedance-matching layer is put on top of the Fibonacci layer. It is shown to absorb roughly 90% of all available electromagnetic waves in an 11 terahertz absorption bandwidth for a transverse magnetic mode at normal angle incidence. The absorption bandwidth is affected by the reflection band gap. Compared with some previous designs, our proposed structure has a larger absorption bandwidth and higher absorption in the mid-infrared range. The results should be valuable in the design of infrared stealth and broadband optoelectronic devices.

  11. Diffusion of Vitamin B12 Across a Mesoporous Metal Organic Framework

    Directory of Open Access Journals (Sweden)

    Veronica Valencia

    2013-01-01

    Full Text Available We measure the rate of uptake and the rate of release of a Vitamin B12 solution (dissolved in water at 2 different temperatures (room temperature and 37°C by the mesoporous metal organic framework TbMOF-100 at 1-hour intervals using a spectrophotometer. Using the Beer-Lambert law, we calculate the concentration of the stock solution based on the absorbance values obtained with the spectrophotometer. These values allow for the quantification of the initial rate of uptake and the rate of uptake at a random incubation time of the Vitamin B12 by the TbMOF-100. We also calculate the value of the coefficient of diffusion for this 2-phase system using Fick’s laws of diffusion.

  12. EM absorption reduction in wireless mobile antenna using printed paper-based metamaterial

    Science.gov (United States)

    Alam, Touhidul; Islam, Mohammad Tariqul; Kibria, Salehin; Cho, Mengu; Faruque, Mohammad Rashed Iqbal

    2017-01-01

    This paper presents a printed negative index metamaterial for electromagnetic (EM) absorption reduction in portable wireless antenna. The perceptible novelty exhibited in this paper is that EM absorption reduction toward the human head with paper-based metamaterial attachment. This research has been performed using human head phantom integrated in the commercially available CST Microwave Studio software package. The EM absorption has been reduced by 13.2 and 6% at 900 and 1800 MHz, respectively.

  13. Oral Cyanocobalamin is Effective in the Treatment of Vitamin B12 Deficiency in Crohn’s Disease

    Science.gov (United States)

    Gomollón, Fernando; Gargallo, Carla J.; Muñoz, Jose Fernando; Vicente, Raquel; Lue, Alberto; Mir, Alberto; García-Alvarado, Marta; Gracia, Marta; García-López, Santiago

    2017-01-01

    Cobalamin deficiency is common in patients with Crohn’s disease (CD). Intramuscular cobalamin continues to be the standard therapy for the deficiency and maintenance treatment in these patients, although oral route has been demonstrated to be effective in other pathologies with impaired absorption. Our aims were to evaluate the efficacy of oral therapy in the treatment of cobalamin deficiency and in long-term maintenance in patients with Crohn’s disease. We performed a multicenter retrospective cohort study that included 94 patients with Crohn’s disease and cobalamin deficiency. Seventy-six patients had B12 deficiency and 94.7% of them normalized their cobalamin levels with oral treatment. The most used dose was 1 mg/day, but there were no significant differences in treatment effectiveness depending on the dose used (≥1 mg/24 h vs. <1 mg/24 h). Eighty-two patients had previous documented B12 deficiency and were treated with oral B12 to maintain their correct cobalamin levels. After a mean follow-up of 3 years, the oral route was effective as maintenance treatment in 81.7% of patients. A lack of treatment adherence was admitted by 46.6% of patients in who the oral route failed. In conclusion, our study shows that oral cyanocobalamin provides effective acute and maintenance treatment for vitamin B12 deficiency caused by CD with or without ileum resection. PMID:28335526

  14. Genome-wide association study of vitamin B6, vitamin B12, folate, and homocysteine blood concentrations.

    Science.gov (United States)

    Tanaka, Toshiko; Scheet, Paul; Giusti, Betti; Bandinelli, Stefania; Piras, Maria Grazia; Usala, Gianluca; Lai, Sandra; Mulas, Antonella; Corsi, Anna Maria; Vestrini, Anna; Sofi, Francesco; Gori, Anna Maria; Abbate, Rosanna; Guralnik, Jack; Singleton, Andrew; Abecasis, Goncalo R; Schlessinger, David; Uda, Manuela; Ferrucci, Luigi

    2009-04-01

    The B vitamins are components of one-carbon metabolism (OCM) that contribute to DNA synthesis and methylation. Homocysteine, a by-product of OCM, has been associated with coronary heart disease, stroke and neurological disease. To investigate genetic factors that affect circulating vitamin B6, vitamin B12, folate and homocysteine, a genome-wide association analysis was conducted in the InCHIANTI (N = 1175), SardiNIA (N = 1115), and BLSA (N = 640) studies. The top loci were replicated in an independent sample of 687 participants in the Progetto Nutrizione study. Polymorphisms in the ALPL gene (rs4654748, p = 8.30 x 10(-18)) were associated with vitamin B6 and FUT2 (rs602662, [corrected] p = 2.83 x 10(-20)) with vitamin B12 serum levels. The association of MTHFR, a gene consistently associated with homocysteine, was confirmed in this meta-analysis. The ALPL gene likely influences the catabolism of vitamin B6 while FUT2 interferes with absorption of vitamin B12. These findings highlight mechanisms that affect vitamin B6, vitamin B12 and homocysteine serum levels.

  15. Oral Cyanocobalamin is Effective in the Treatment of Vitamin B12 Deficiency in Crohn’s Disease

    Directory of Open Access Journals (Sweden)

    Fernando Gomollón

    2017-03-01

    Full Text Available Cobalamin deficiency is common in patients with Crohn’s disease (CD. Intramuscular cobalamin continues to be the standard therapy for the deficiency and maintenance treatment in these patients, although oral route has been demonstrated to be effective in other pathologies with impaired absorption. Our aims were to evaluate the efficacy of oral therapy in the treatment of cobalamin deficiency and in long-term maintenance in patients with Crohn’s disease. We performed a multicenter retrospective cohort study that included 94 patients with Crohn’s disease and cobalamin deficiency. Seventy-six patients had B12 deficiency and 94.7% of them normalized their cobalamin levels with oral treatment. The most used dose was 1 mg/day, but there were no significant differences in treatment effectiveness depending on the dose used (≥1 mg/24 h vs. <1 mg/24 h. Eighty-two patients had previous documented B12 deficiency and were treated with oral B12 to maintain their correct cobalamin levels. After a mean follow-up of 3 years, the oral route was effective as maintenance treatment in 81.7% of patients. A lack of treatment adherence was admitted by 46.6% of patients in who the oral route failed. In conclusion, our study shows that oral cyanocobalamin provides effective acute and maintenance treatment for vitamin B12 deficiency caused by CD with or without ileum resection.

  16. Stabilization of Mass Absorption Cross Section of Elemental Carbon for Filter-Based Absorption Photometer by Heated Inlet

    Science.gov (United States)

    Kondo, Y.; Sahu, L.; Takegawa, N.; Miyazaki, Y.; Han, S.; Moteki, N.; Hu, M.; Kim Oanh, N.; Kim, Y.

    2008-12-01

    Accurate measurements of elemental carbon (EC) or black carbon on a long-term basis are important for the studies of impacts of EC on climate and human health. In principle, mass concentrations of EC (MEC) can be estimated by the measurement of light absorption coefficient by EC. Filter-based methods, which quantify the absorption coefficient (kabs) from the change in transmission through a filter loaded with particles, have been widely used to measure MEC because of the ease of the operation. However, in practice, reliable determination of MEC has been very difficult because of the large variability in the mass absorption cross sections (Cabs), which is a conversion factor from kabs to MEC. Coating of EC by volatile compounds and co-existence of light-scattering particles greatly contributes to the variability of Cabs. In order to overcome this difficulty, volatile aerosol components were removed before collection of EC particles on filters by heating an inlet section to 400°C. The heated inlet vaporized almost completely sulfate, nitrate, ammonium, and organics without any detectable loss of EC. Simultaneous measurements of kabs by two types photometers (Particle Soot Absorption Photometer (PSAP) and Continuous Soot Monitoring System (COSMOS)) together with MEC by the EC-OC analyzer were made to determine Cabs at 6 different locations in Asia (Japan, Korea, China, and Thailand) in different seasons. The Cabs was stable to be 10.5±0.7 m2 g-1 at the wavelength of 565 nm for EC strongly impacted by emissions from vehicles and biomass burning. The stability of the Cabs for different EC sources and under the different physical and chemical conditions provides a firm basis for its use in estimating MEC in fine mode with an accuracy of about 10%.

  17. Methylcobalamin--a form of vitamin B12 identified and characterised in Chlorella vulgaris.

    Science.gov (United States)

    Kumudha, Anantharajappa; Selvakumar, Sagaya; Dilshad, Pullancheri; Vaidyanathan, Gopal; Thakur, Munna Singh; Sarada, Ravi

    2015-03-01

    Vitamin B12 is among the most essential biomolecules required for crucial metabolic processes in humans. Vitamin B12 was extracted from Chlorella vulgaris biomass under aqueous conditions, partially purified by passing the extract through amberlite XAD-2, Sep-Pak columns, and further purified by HPLC. The target peak eluent was subjected to characterisation by tandem mass spectrometry (MS/MS), selected ion recording (SIR) and multiple reaction monitoring (MRM) and identified as methylcobalamin (Me-Cbl). Quantification of Me-Cbl was carried out by microbiological and chemiluminescence methods, and found to be 29.87±2 μg/100 g and 26.84±2 μg/100 g dry weight, respectively. The presence of Me-Cbl was further substantiated using gold nanoparticle (AuNPs) based aptamer analysis, and found to be 28.02±2 μg/100 g dry weight. Good similarity was observed among all the methods. Methylcobalamin, a form of vitamin B12 was identified in C. vulgaris and this finding enhances its use as a nutritional supplement.

  18. Vitamin B12 status in older adults living in Ontario long-term care homes: prevalence and incidence of deficiency with supplementation as a protective factor.

    Science.gov (United States)

    Pfisterer, Kaylen J; Sharratt, Mike T; Heckman, George G; Keller, Heather H

    2016-02-01

    Vitamin B12 (B12) deficiency, although treatable, impacts up to 43% of community-living older adults; long-term care (LTC) residents may be at greater risk. Recommendations for screening require further evidence on prevalence and incidence in LTC. Small, ungeneralizable samples provide a limited perspective on these issues. The purposes of this study were to report prevalence of B12 deficiency at admission to LTC, incidence 1 year post-admission, and identify subgroups with differential risk. This multi-site (8), retrospective prevalence study used random proportionate sampling of resident charts (n = 412). Data at admission extracted included demographics, B12 status, B12 supplementation, medications, diagnoses, functional independence, cognitive performance, and nutrition. Prevalence at admission of B12 deficiency (B12 (>300 pmol/L). One year post-admission incidence was 4%. Better B12 status was significantly associated with supplementation use prior to LTC admission. Other characteristics were not associated with status. This work provides a better estimate of B12 deficiency prevalence than previously available for LTC, upon which to base protocols and policy. Prospective studies are needed to establish treatment efficacy and effect on health related outcomes.

  19. Rapidly reconfigurable slow-light system based on off-resonant Raman absorption

    Science.gov (United States)

    Vudyasetu, Praveen K.; Camacho, Ryan M.; Howell, John C.

    2010-11-01

    We present a slow-light system based on dual Raman absorption resonances in warm rubidium vapor. Each Raman absorption resonance is produced by a control beam in an off-resonant Λ system. This system combines all optical control of the Raman absorption and the low-dispersion broadening properties of the double Lorentzian absorption slow light. The bandwidth, group delay, and central frequency of the slow-light system can all be tuned dynamically by changing the properties of the control beam. We demonstrate multiple pulse delays with low distortion and show that such a system has fast switching dynamics and thus fast reconfiguration rates.

  20. Mathematical Model of Natural Gas Desulfurization Based on Membrane Absorption

    Institute of Scientific and Technical Information of China (English)

    Wang Shuli; Ma Jun; Wang Ganyu; Zhou Heng

    2014-01-01

    Models of mass transfer kinetics combined with mass transfer differential equation and mass transfer resistance equation were established on the basis of double-iflm theory. Mass transfer process of H2S absorption by means of polypro-pylene hydrophobic microporous hollow ifber membrane contactor was simulated using MDEA (N-methyldiethanolamine) as the absorption liquid and corresponding experiments of natural gas desulfurization were performed. The simulation re-sults indicated that the removal rate of hydrogen sulifde showed positive dependence on the absorption liquid concentration and gas pressure. However, the desulfurization rate showed negative dependence on gas lfow. The simulated values were in good agreement with the experimental results. The in-tube concentration of hydrogen sulifde at the same point increased with increase in the gas velocity. Axial concentration of hydrogen sulifde decreased rapidly at the beginning, and the de-crease saw a slowdown during the latter half period. Hydrogen sulifde concentration dropped quickly in the radial direction, and the reduction in the radial direction was weakened with the increase of axial length due to the gradual reduction of hy-drogen sulifde concentration along the tube. The desulfurization rate under given operating conditions can be predicted by this model, and the theoretical basis for membrane module design can also be provided.

  1. Effects of Chemical and Physical Enhancement Techniques on Transdermal Delivery of Cyanocobalamin (Vitamin B12 In Vitro

    Directory of Open Access Journals (Sweden)

    Ajay K. Banga

    2011-08-01

    Full Text Available Vitamin B12 deficiency, which may result in anemia and nerve damage if left untreated, is currently treated by administration of cyanocobalamin via oral or intramuscular routes. However, these routes are associated with absorption and compliance issues which have prompted us to investigate skin as an alternative site of administration. Delivery through skin, however, is restricted to small and moderately lipophilic molecules due to the outermost barrier, the stratum corneum (SC. In this study, we have investigated the effect of different enhancement techniques, chemical enhancers (ethanol, oleic acid, propylene glycol, iontophoresis (anodal iontophoresis and microneedles (soluble maltose microneedles, which may overcome this barrier and improve cyanocobalamin delivery. Studies with different chemical enhancer formulations indicated that ethanol and oleic acid decreased the lag time while propylene glycol based formulations increased the lag time. The formulation with ethanol (50%, oleic acid (10% and propylene glycol (40% showed the maximum improvement in delivery. Iontophoresis and microneedle treatments resulted in enhanced permeation levels compared to passive controls. These enhancement approaches can be explored further to develop alternative treatment regimens.

  2. Development on Fermentation Process of Vitamin B12%维生素B12发酵工艺进展

    Institute of Scientific and Technical Information of China (English)

    程瑶

    2012-01-01

    综述了维生素B12(VB12)发酵工艺路线、菌种选育、工艺优化等方面的研究进展,展望了VB12发酵工艺发展前景。%To Summary the fermentation process route,process optimization and strain transformation of vitamin B12. To prospect the development of vitamin B12.

  3. Cognitive and psychiatric effects of vitamin B12 replacement in dementia with low serum B12 levels: a nursing home study

    Science.gov (United States)

    van Dyck, Christopher H.; Lyness, Jeffrey M.; Rohrbaugh, Robert M.; Siegal, Alan P.

    2012-01-01

    Background The aim of this study is to determine whether B12 replacement would ameliorate cognitive and psychiatric symptoms in elderly subjects with dementia and low serum B12 levels. Methods A test group (n=28) of nursing home residents with low serum B12 levels (B12 levels (>300 pg/mL) were evaluated by blinded raters while the test group received intramuscular (IM) B12 replacement therapy. All subjects were assessed at baseline, 8 weeks, and 16 weeks with the Dementia Rating Scale, Brief Psychiatric Rating Scale, and Geriatric Depression Scale. Results Although B12 replacement produced significant improvement in hematologic and metabolic parameters, it yielded no significant effect on cognitive or psychiatric variables. A few subjects evidenced notable individual treatment responses; however, these were not statistically more frequent than in the normal B12 group. Conclusions These results suggest that B12 replacement is unlikely to benefit cognitive or psychiatric symptoms in the vast majority of elderly dementia patients with low serum B12 levels. PMID:18925978

  4. Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency.

    Science.gov (United States)

    Hannibal, Luciana; Lysne, Vegard; Bjørke-Monsen, Anne-Lise; Behringer, Sidney; Grünert, Sarah C; Spiekerkoetter, Ute; Jacobsen, Donald W; Blom, Henk J

    2016-01-01

    Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders.

  5. Biomarkers and Algorithms for the Diagnosis of Vitamin B12 Deficiency

    Science.gov (United States)

    Hannibal, Luciana; Lysne, Vegard; Bjørke-Monsen, Anne-Lise; Behringer, Sidney; Grünert, Sarah C.; Spiekerkoetter, Ute; Jacobsen, Donald W.; Blom, Henk J.

    2016-01-01

    Vitamin B12 (cobalamin, Cbl, B12) is an indispensable water-soluble micronutrient that serves as a coenzyme for cytosolic methionine synthase (MS) and mitochondrial methylmalonyl-CoA mutase (MCM). Deficiency of Cbl, whether nutritional or due to inborn errors of Cbl metabolism, inactivate MS and MCM leading to the accumulation of homocysteine (Hcy) and methylmalonic acid (MMA), respectively. In conjunction with total B12 and its bioactive protein-bound form, holo-transcobalamin (holo-TC), Hcy, and MMA are the preferred serum biomarkers utilized to determine B12 status. Clinically, vitamin B12 deficiency leads to neurological deterioration and megaloblastic anemia, and, if left untreated, to death. Subclinical vitamin B12 deficiency (usually defined as a total serum B12 of vitamin B12 has limited diagnostic value as a stand-alone marker. Low serum levels of vitamin B12 not always represent deficiency, and likewise, severe functional deficiency of the micronutrient has been documented in the presence of normal and even high levels of serum vitamin B12. This review discusses the usefulness and limitations of current biomarkers of B12 status in newborn screening, infant and adult diagnostics, the algorithms utilized to diagnose B12 deficiency and unusual findings of vitamin B12 status in various human disorders. PMID:27446930

  6. Prevalence of Relative Deficiencies in Testosterone and Vitamin B12 Among Patients Referred for Chronic Orchialgia: Implications for Management.

    Science.gov (United States)

    Cui, Tao; Terlecki, Ryan

    2016-04-08

    Chronic testicular pain (CTP) is a complex pain syndrome that is widely variable in presentation and etiology. Many cases of CTP are thought to be associated with neuropathy and recent data suggest an inflammation-mediated process is more common among patients with CTP. Deficiencies in vitamin B12 and testosterone are common in chronic pain syndromes may play a role in CTP. A retrospective review of men treated for CTP by a single provider over a 2-year period was performed. Patients with serum screening of testosterone and B12 were selected. Patients with total testosterone below 300 ng/dl, free testosterone below 46 pg/ml, or B12 below 400 pg/ml were deemed deficient and offered repletion. Efficacy of treatment was measured based on patient report with a minimum follow-up of either 3 months or resolution of pain symptoms. One hundred and fifty-four (154) men with CTP were identified, with 125 assessed for testosterone and B12 levels. Of these, 95 patients (76%) were deemed deficient. Fifty-six (56) patients elected to receive B12/testosterone replacement. In patients with sufficient follow-up, 24 patients (65%) reported significant improvement of symptoms, 6 patients (16%) reported some improvement, and 7 patients (19%) reported no improvement. The prevalence of testosterone and B12 deficiencies in this study is much higher than that reported for the general population. In addition, when chemical deficiencies were corrected, greater than 80% of patients with sufficient follow-up reported some improvement in pain. This suggests that screening of B12 and testosterone should be incorporated into the assessment of patients with CTP.

  7. Is there an association of vitamin B12 status with neurological function in older people? A systematic review.

    Science.gov (United States)

    Miles, Lisa M; Mills, Kerry; Clarke, Robert; Dangour, Alan D

    2015-08-28

    Low vitamin B12 status is common in older people; however, its public health significance in terms of neurological manifestations remains unclear. The present systematic review evaluated the association of vitamin B12 status with neurological function and clinically relevant neurological outcomes in adults aged 50+ years. A systematic search of nine bibliographic databases (up to March 2013) identified twelve published articles describing two longitudinal and ten cross-sectional analyses. The included study populations ranged in size (n 28-2287) and mean/median age (range 65-81 years). Studies reported various neurological outcomes: nerve function; clinically measured signs and symptoms of nerve function; self-reported neurological symptoms. Studies were assessed for risk of bias, and results were synthesised qualitatively. Among the general population groups of older people, one longitudinal study reported no association, and four of seven cross-sectional studies reported limited evidence of an association of vitamin B12 status with some, but not all, neurological outcomes. Among groups with clinical and/or biochemical evidence of low vitamin B12 status, one longitudinal study reported an association of vitamin B12 status with some, but not all, neurological outcomes and three cross-sectional analyses reported no association. Overall, there is limited evidence from observational studies to suggest an association of vitamin B12 status with neurological function in older people. The heterogeneity and quality of the evidence base preclude more definitive conclusions, and further high-quality research is needed to better inform understanding of public health significance in terms of neurological function of vitamin B12 status in older people.

  8. Homocysteine, vitamin B12 and folate levels in premature coronary artery disease

    Directory of Open Access Journals (Sweden)

    Fallah Nader

    2006-09-01

    Full Text Available Abstract Background Hyperhomocysteinemia is known as an independent risk factor of atherosclerosis, but the probable role of hyperhomocysteinemia in premature Coronary Artery Disease (CAD is not well studied. The aim of this study was to assess the role of hyperhomocysteinemia, folate and Vitamin B12 deficiency in the development of premature CAD. Methods We performed an analytical case-control study on 294 individuals under 45 years (225 males and 69 females who were admitted for selective coronary angiography to two centers in Tehran. Results After considering the exclusion criteria, a total number of 225 individuals were enrolled of which 43.1% had CAD. The mean age of participants was 39.9 +/- 4.3 years (40.1 +/- 4.2 years in males and 39.4 +/- 4.8 years in females. Compared to the control group, the level of homocysteine measured in the plasma of the male participants was significantly high (14.9 +/- 1.2 versus 20.3 +/- 1.9 micromol/lit, P = 0.01. However there was no significant difference in homocysteine level of females with and without CAD (11.8 +/- 1.3 versus 11.5 ± 1.1 micromol/lit, P = 0.87. Mean plasma level of folic acid and vitamin B12 in the study group were 6.3 +/- 0.2 and 282.5 +/- 9.1 respectively. Based on these findings, 10.7% of the study group had folate deficiency while 26.6% had Vitamin B12 deficiency. Logistic regression analysis for evaluating independent CAD risk factors showed hyperhomocysteinemia as an independent risk factor for premature CAD in males (OR = 2.54 0.95% CI 1.23 to 5.22, P = 0.01. Study for the underlying causes of hyperhomocysteinemia showed that male gender and Vitamin B12 deficiency had significant influence on incidence of hyperhomocysteinemia. Conclusion We may conclude that hyperhomocysteinemia is an independent risk factor for CAD in young patients (bellow 45 years old – especially in men -and vitamin B12 deficiency is a preventable cause of hyperhomocysteinemia.

  9. Nutrient Acquisition: The Generation of Bioactive Vitamin B12 by Microalgae

    National Research Council Canada - National Science Library

    Grossman, Arthur

    2016-01-01

    Many microalgae acquire vitamin B12 from marine prokaryotes. A new study demonstrates that vitamin B12 is synthesized by planktonic cyanobacteria as pseudocobalamin, a form not bioactive in microalgae...

  10. Vitamin B12 is the active corrinoid produced in cultivated white button mushrooms (Agaricus bisporus).

    Science.gov (United States)

    Koyyalamudi, Sundar Rao; Jeong, Sang-Chul; Cho, Kai Yip; Pang, Gerald

    2009-07-22

    Analysis of vitamin B(12) in freshly harvested white button mushrooms ( Agaricus bisporus ) from five farms was performed by affinity chromatography and HPLC-ESI-MS techniques. The vitamin B(12) concentrations obtained varied from farm to farm, with higher concentrations of vitamin B(12) detected in outer peel than in cap, stalk, or flesh, suggesting that the vitamin B(12) is probably bacteria-derived. High concentrations of vitamin B(12) were also detected in the flush mushrooms including cups and flats. HPLC and mass spectrometry showed vitamin B(12) retention time and mass spectra identical to those of the standard vitamin B(12) and those of food products including beef, beef liver, salmon, egg, and milk but not of the pseudovitamin B(12), an inactive corrinoid in humans. The results suggest that the consumer may benefit from the consumption of mushroom to increase intake of this vitamin in the diet.

  11. Megalin is essential for renal proximal tubule reabsorption and accumulation of transcobalamin-B(12)

    DEFF Research Database (Denmark)

    Birn, Henrik; Willnow, Thomas E; Nielsen, Rikke;

    2002-01-01

    Megalin has previously been shown to bind and mediate endocytosis of transcobalamin (TC)-B(12). However, the physiological significance of this has not been established, and other TC-B(12) binding proteins have been suggested to mediate renal uptake of this vitamin complex. The present study...... demonstrates by the use of megalin-deficient mice that megalin is, in fact, essential for the normal renal reabsorption of TC-vitamin B(12) and for renal accumulation of this highly conserved vitamin. Megalin-deficient mice excrete increased amounts of TC and B(12) in the urine, revealing a defective renal...... tubular uptake of TC-B(12). The urinary B(12) excretion is increased approximately 4-fold, resulting in an approximately 28-fold higher renal B(12) clearance. This is associated with an approximately 4-fold decrease in B(12) content in megalin-deficient kidney cortex. Thus megalin is important to prevent...

  12. Vitamin B12 transport from food to the body's cells--a sophisticated, multistep pathway

    DEFF Research Database (Denmark)

    Nielsen, Marianne J; Rasmussen, Mie R; Andersen, Christian B F

    2012-01-01

    Vitamin B(12) (B(12); also known as cobalamin) is a cofactor in many metabolic processes; deficiency of this vitamin is associated with megaloblastic anaemia and various neurological disorders. In contrast to many prokaryotes, humans and other mammals are unable to synthesize B(12). Instead...... in the transport pathway are also known culprits of functional B(12) deficiency. Biochemical and genetic approaches have identified novel proteins in the B(12) transport pathway--now known to involve more than 15 gene products--delineating a coherent pathway for B(12) trafficking from food to the body's cells....... Some of these gene products are specifically dedicated to B(12) transport, whereas others embrace additional roles, which explains the heterogeneity in the clinical picture of the many genetic disorders causing B(12) deficiency. This Review describes basic and clinical features of this multistep...

  13. Serum vitamin B12 levels during the first trimester of pregnancy correlate with newborn screening markers of vitamin B12 deficiency.

    Science.gov (United States)

    Dayaldasani, Anita; Ruiz-Escalera, Juan; Rodríguez-Espinosa, Manuel; Rueda, Inmaculada; Pérez-Valero, Vidal; Yahyaoui, Raquel

    2014-01-01

    Low maternal vitamin B12 status is a risk factor for various adverse pregnancy outcomes. Although vitamin B12 deficiency is not a primary target of newborn screening (NBS) programs, measurements of propionylcarnitine (C3) and its ratios with acetylcarnitine (C3/C2) and palmitoylcarnitine (C3/C16) may incidentally identify vitamin B12-deficient newborns. The objective of this study was to measure vitamin B12 levels in women during the first trimester of pregnancy, evaluate predictors of these concentrations, and study their relationship with newborn screening results. Vitamin B12 concentrations were evaluated in 204 women during the first trimester of pregnancy and possible confounding factors were analyzed. After giving birth, data of their newborns (189) were collected (sex, gestational age, birthweight) and the acylcarnitine profile obtained by tandem mass spectrometry during NBS was analyzed. To assess the effects of the variables on vitamin B12 serum concentrations and newborn screening markers, stepwise multiple linear regression models were used. The mean serum concentration of vitamin B12 was 370.8 pmol/L (502.4 pg/mL) (SD 142.81). Vitamin B12 concentrations were significantly lower in smokers (p=0.027), and in women with low meat consumption (p=0.040). There was a significant inverse correlation between mothers'’ vitamin B12 concentrations and their children’'s C3 (r=-0.24; p=0.001), C3/C2 (r=-0.23; p=0.002) and C3/C16 levels (r=-0.20; p=0.006). Newborn screening markers (C3, C3/C2, and C3/C16) present an inverse correlation with maternal vitamin B12 status in the first trimester of pregnancy. Regarding factors that may influence maternal serum vitamin B12 levels during the first trimester, smoking seems to have a negative effect, and meat consumption a positive effect.

  14. Prevalent vitamin B-12 deficiency in twelve-month-old Guatemalan infants is predicted by maternal B-12 deficiency and infant diet.

    Science.gov (United States)

    Jones, Katharine M; Ramirez-Zea, Manuel; Zuleta, Clara; Allen, Lindsay H

    2007-05-01

    Approximately one-third of low-income women and children studied in Guatemala are reported to have deficient (deficiency can adversely affect infant development and cognitive function, the present study examined predictors of deficient plasma vitamin B-12 concentrations at the age of 12 mo. Analyses were performed on baseline data from a randomized clinical trial in 304 Guatemalan infants, 80% of whom were partially breast-fed, and their mothers. Exclusion criteria for infants included twins, severe stunting or moderate wasting, reported major health problems, severe developmental delay, hemoglobin 3 mo. Data collected included socio-economic status, infant anthropometry, vitamin B-12 intake from complementary foods, and breast-feeding frequency reported by mothers. A complete blood count and plasma vitamin B-12, folate, ferritin, and C-reactive protein were measured. Deficient or marginal plasma vitamin B-12 concentrations were found in 49% of infants and 68% of mothers. The mean intake of maternal vitamin B-12 was 3.1 microg/d, and infants consumed 2.2 microg/d from complementary foods. In linear regression analysis, infant plasma B-12 concentration was strongly and positively associated with maternal plasma vitamin B-12 and B-12 intake from complementary foods (predominantly powdered cow's milk), and inversely associated with frequency of breast-feeding and larger household size (P < 0.0001). Vitamin B-12 supplementation of lactating women, food fortification, and education to improve infant's vitamin B-12 status are potential interventions that can improve the vitamin B-12 status of mothers and infants in this population.

  15. Link between vitamin B12, type 2 diabetes mellitus, and bone mineral density in elderly patients

    Directory of Open Access Journals (Sweden)

    Moatassem S. Amer, MD

    2015-12-01

    Conclusion: The prevalence of vitamin B12 deficiency was higher in the control group than the diabetic group who did not receive oral B12 supplementation. Low serum vitamin B12 is commonly overlooked in the elderly, with or without diabetes. The presence of diabetes mellitus did not affect BMD in the elderly. Furthermore, there is no significant relationship between serum vitamin B12 levels and BMD among diabetics.

  16. Association of Vitamin B12 Deficiency with Homozygosity of the TT MTHFR C677T Genotype, Hyperhomocysteinemia, and Endothelial Cell Dysfunction.

    Science.gov (United States)

    Shiran, Avinoam; Remer, Eric; Asmer, Ihab; Karkabi, Basheer; Zittan, Eran; Cassel, Aliza; Barak, Mira; Rozenberg, Orit; Karkabi, Khaled; Flugelman, Moshe Y

    2015-05-01

    Hyperhomocysteinemia is associated with increased cardiovascular risk, but treatment with folic acid has no effect on outcome in unselected patient populations. To confirm previous observations on the association of homozygosity for the TT MTHFR genotype with B12 deficiency and endothelial dysfunction, and to investigate whether patients with B12 deficiency should be tested for 677MTHFR genotype. We enrolled 100 individuals with B12 deficiency, tested them for the MTHFR C677T polymorphism and measured their homocysteine levels. Forearm endothelial function was checked in 23 B12-deficient individuals (13 with TT MTHFR genotype and 10 with CT or CC genotypes). Flow-mediated dilatation (FMD) was tested after short-term treatment with B12 and folic acid in 12 TT MTHFR homozygotes. Frequency of the TT MTHFR genotype was 28/100 (28%), compared with 47/313 (15%) in a previously published cohort of individuals with normal B12 levels (P = 0.005). Mean homocysteine level was 21.2 ± 16 μM among TT homozygotes as compared to 12.3 ± 5.6 μM in individuals with the CC or CT genotype (P = 0.008). FMD was abnormal ( 6%) in 9/13 TT individuals with B12 deficiency (69%), and was still abnormal in 7/12 of those tested 6 weeks after B12 and folic treatment (58%). Among individuals with B12 deficiency, the frequency of the TT MTHFR genotype was particularly high. The TT polymorphism was associated with endothelial dysfunction even after 6 weeks of treatment with B12 and folic acid. Based on our findings we suggest that B12 deficiency be tested for MTHFR polymorphism in order to identify potential vascular abnormalities and increased cardiovascular risk.

  17. Efeito da corticotropina sobre a absorção de vitamina B12 na mielose funicular

    Directory of Open Access Journals (Sweden)

    Horacio M. Canelas

    1965-06-01

    Full Text Available Foi estudada a absorção de vitamina B12 em 9 casos de mielose funicular antes e após a administração de ACTH por via intravenosa em um esquema terapêutico com duração variável entre 19 e 43 dias. Em 7 casos foi verificado aumento da absorção. A diferença média de modificação no teste de excreção urinaria de vitamina B12 radioativa situou-se próximo do nível de significancia estatística. Este resultado reforça a indicação do emprego de corticotropina na mielose funicular, pois o hormônio irá atuar tanto sobre o componente alérgico do prccesso desmielinizante, quanto sobre a carência de vitamina B12 resultante do déficit de absorção. Embora o material aqui analisado seja muito pequeno para garantir uma conclusão definitiva, nossos resultados demonstram que, provavelmente, o ACTH age sobre a absorção da vitamina B12 através da mucosa intestinal, e não mediante o aumento de secreção do fator intrínseco ou a mobilização dos depósitos dessa vitamina. In order to study a possible mobilizing effect of ACTH on the radioactive vitamin B12 stores, the intervals between the last urinary excretion test and the test after completion of treatment were analyzed (Table 1. It is easily noticed that in the 7 cases with increase of vitamin B12 absorption these periods were the most varied, lasting from 9 to 62 days. And also in the 2 cases with decrease of absorption the intervals were very dissimilar, namely 15 and 56 days. So, it seems that this effect of ACTH did not play a significant role in the results. Likewise, the time elapsed between the completion of treatment and the repetition of the Schilling's test had no apparent relationship with the results.

  18. Peak, multi-peak and broadband absorption in graphene-based one-dimensional photonic crystal

    Science.gov (United States)

    Miloua, R.; Kebbab, Z.; Chiker, F.; Khadraoui, M.; Sahraoui, K.; Bouzidi, A.; Medles, M.; Mathieu, C.; Benramdane, N.

    2014-11-01

    We theoretically investigate the possibility of enhancing light absorption in graphene-based one dimensional photonic crystal. We demonstrate that it is possible to achieve total light absorption at technologically important wavelengths using one-dimensional graphene-based photonic crystals. By means of the transfer matrix method, we investigate the effect of refractive indices and layer numbers on the optical response of the structure. We found that it is possible to achieve one peak, multi-peak or broadband, and complete optical absorption. As a result, the proposed photonic structures enable myriad potential applications such as photodetection, shielding and optical sensing.

  19. Neonatal vitamin B12 deficiency secondary to maternal subclinical pernicious anemia: identification by expanded newborn screening.

    Science.gov (United States)

    Marble, Michael; Copeland, Sara; Khanfar, Nashat; Rosenblatt, David S

    2008-05-01

    A neonate with elevated propionylcarnitine on the newborn screen was found to have methylmalonic acidemia due to vitamin B(12) deficiency. The mother was also vitamin B(12)-deficient. This case illustrates the utility of expanded newborn screening for detection of vitamin B(12) deficiency, allowing prompt treatment and prevention of potential sequelae.

  20. Vitamin B12 Inhibits Tau Fibrillization via Binding to Cysteine Residues of Tau.

    Science.gov (United States)

    Rafiee, Saharnaz; Asadollahi, Kazem; Riazi, Gholamhossein; Ahmadian, Shahin; Saboury, Ali Akbar

    2017-09-06

    Two mechanisms underlie the inhibitory/acceleratory action of chemical compounds on tau aggregation including the regulation of cellular kinases and phosphatases activity and direct binding to tau protein. Vitamin B12 is one of the tau polymerization inhibitors, and its deficiency is linked to inactivation of protein phosphatase 2A and subsequently hyperphosphorylation and aggregation of tau protein. Regarding the structure and function of vitamin B12 and tau protein, we assumed that vitamin B12 is also able to directly bind to tau protein. Hence, we investigated the interaction of vitamin B12 with tau protein in vitro using fluorometry and circular dichrosim. Interaction studies was followed by investigation into the effect of vitamin B12 on tau aggregation using ThT fluorescence, circular dichroism, transmission electron microscopy, and SDS-PAGE. The results indicated that vitamin B12 interacts with tau protein and prevents fibrillization of tau protein. Blocking the cysteine residues of tau confirmed the cysteine-mediated binding of vitamin B12 to tau and showed that binding to cysteine is essential for inhibitory effect of vitamin B12 on tau aggregation. SDS-PAGE analysis indicated that vitamin B12 inhibits tau aggregation and that tau oligomers formed in the presence of vitamin B12 are mostly SDS-soluble. We propose that direct binding of vitamin B12 is another mechanism underlying the inhibitory role of vitamin B12 on tau aggregation and neurodegeneration.

  1. Nutrient Acquisition: The Generation of Bioactive Vitamin B12 by Microalgae.

    Science.gov (United States)

    Grossman, Arthur

    2016-04-25

    Many microalgae acquire vitamin B12 from marine prokaryotes. A new study demonstrates that vitamin B12 is synthesized by planktonic cyanobacteria as pseudocobalamin, a form not bioactive in microalgae. However, some microalgae can remodel pseudocobalamin to the active cobalamin form, adding complexity to our assessment of active vitamin B12 in the environment.

  2. Multivitamin Use and Serum Vitamin B12 Concentrations in Older-Adult Metformin Users in REGARDS, 2003-2007.

    Science.gov (United States)

    Kancherla, Vijaya; Garn, Joshua V; Zakai, Neil A; Williamson, Rebecca S; Cashion, Winn T; Odewole, Oluwaseun; Judd, Suzanne E; Oakley, Godfrey P

    2016-01-01

    Metformin, an insulin-sensitizing drug, is a first line treatment for type 2 diabetes. Long-term use of metformin has been associated with subsequent reductions in vitamin B12 concentrations. The objective of our study was to determine whether metformin use is associated with lower serum vitamin B12 concentrations in older adults, and whether concurrent use of multivitamins modifies this association. We examined 2,510 participants aged 50 years and over, participating in the national population-based Reasons for Geographic And Racial Differences in Stroke (REGARDS) Study. Multivariable linear and logistic regression models were used to assess associations between multivitamin use and serum vitamin B12 concentrations. We estimated adjusted odds ratios (aOR)s and confidence intervals (CI)s. Results were stratified by three metformin/diabetes sub-groups: 1) participants with diabetes who were metformin users; 2) participants with diabetes who were not metformin users; and 3) participants without diabetes. We found that diabetic metformin users had significantly lower geometric mean serum B12 concentrations (409 pmol/L) than the group with diabetes not taking metformin (485 pmol/L; PB12 concentrations were greater for multivitamin users (509 pmol/L) compared to those who did not use multivitamins (376 pmol/L; pvitamin B12 concentrations that were 50% (or 161 pmol/L) higher, compared to those not using multivitamins. Among metformin users, multivitamin use was associated with lower prevalence of combined low and borderline vitamin B12 concentrations (aOR = 0.14; 95% CI = 0.04, 0.54) compared to those not using multivitamins. In conclusion, metformin use was associated with lower geometric mean serum vitamin B12 concentrations among diabetic older adults compared to their counterparts. Concurrent multivitamin use may potentially protect against low or borderline vitamin B12 concentrations in long-term metformin users. Additional research is needed to further examine this

  3. Proton-pump inhibitor therapy and vitamin B12 status in an inpatient hospital setting.

    Science.gov (United States)

    Hartman, Brenda; Donnelly-VanderLoo, Mary; Watson, Tiffany; O'Connor, Colleen; Madill, Janet

    2016-06-23

    The risk for impaired vitamin B12 status increases with age, as does the use of proton pump inhibitors (PPI). Long-term use of PPIs is associated with several nutritional deficiencies including B12. Currently, there are no recommendations for B12 screening among patients taking PPIs. Data were abstracted on B12 concentrations, B12-containing supplement use, medications, and select hematological values from a retrospective chart review of 658 adults, 391 with serum B12 concentrations, admitted to 6 different medical units at 2 regional hospitals in Southwestern Ontario between 2010 and 2012. We found no difference between PPI users and nonusers and serum B12 concentrations (404 ± 224 vs 369 ± 213 pmol/L; P = 0.0690). This may be due to use of B12 containing multivitamins in 41% of PPI users. Regression modelling found that aging increases the odds of having an impaired B12 status (B12 supplements are almost 4 times more likely to have an impaired status. Mean corpuscular volume was not related to B12 status. In this population, older PPI users are more likely to be using multivitamins, which may delay nutritional deficiencies. However, the lower B12 concentrations of PPI users taking only B12 supplements is a concern and requires further research. Finally, physicians need to be aware that mean corpuscular volume is no longer recommended as an effective biomarker for B12 screening and updated screening protocols need to be used to reduce the possibility of adverse neurological effects from impaired B12 status.

  4. Application of Vitamin B12 to Oral Ulcer%维生素B12在治疗口腔溃疡中的应用

    Institute of Scientific and Technical Information of China (English)

    涂晓田; 杨为民; 胡伊乐

    2014-01-01

    目的:探讨维生素B12在治疗口腔溃疡中的实际效果。方法将口腔溃疡患者随机分成4组,分别外敷维生素B12、维生素B2、冰硼散、氯已定含片,对比各组在愈合时间与疼痛抑制方面差别。结果外敷维生素 B12组在愈合时间与疼痛抑制方面明显优于其他组。结论维生素 B12在治疗口腔溃疡时不但愈合时间短于其他药物,而且能有效地抑制疼痛,可以作为一种治疗方法在临床应用。%Objective To explore the actual result of vitamin B12 in curing oral ulcer. Methods The groups in which the patients were divided in to four at random were external by applied Vitamin B12,Vitamin B2 ,Bingpeng powder,Chlorhexidine mouth lozenge differently to compare the differences of every group in healing time and pain suppression. Results The group externally applied by Vitamin B12 was better than the other groups in healing time and pain suppression. Conclusion When curing the oral ulcer,the healing time of Vitamin B12 is shorter than other drugs and Vitamin B12 and can suppress pain effectively.So the method of applying Vitamin B12 may become a new therapeutic method in clinical application in future.

  5. [The Research for Trace Ammonia Escape Monitoring System Based on Tunable Diode Laser Absorption Spectroscopy].

    Science.gov (United States)

    Zhang, Li-fang; Wang, Fei; Yu, Li-bin; Yan, Jian-hua; Cen, Ke-fa

    2015-06-01

    In order to on-line measure the trace ammonia slip of the commercial power plant in the future, this research seeks to measure the trace ammonia by using tunable diode laser absorption spectroscopy under ambient temperature and pressure, and at different temperatures, and the measuring temperature is about 650 K in the power plant. In recent years lasers have become commercially available in the near-infrared where the transitions are much stronger, and ammonia's spectroscopy is pretty complicated and the overlapping lines are difficult to resolve. A group of ammonia transitions near 4 433.5 cm(-1) in the v2 +v3 combination band have been thoroughly selected for detecting lower concentration by analyzing its absorption characteristic and considering other absorption interference in combustion gases where H2O and CO2 mole fraction are very large. To illustrate the potential for NH3 concentration measurements, predictions for NH3, H2O and CO2 are simultaneously simulated, NH3 absorption lines near 4 433.5 cm(-1) wavelength meet weaker H2O absorption than the commercial NH3 lines, and there is almost no CO2 absorption, all the parameters are based on the HITRAN database, and an improved detection limit was obtained for interference-free NH3 monitoring, this 2.25 μm band has line strengths several times larger than absorption lines in the 1.53 μm band which was often used by NH3 sensors for emission monitoring and analyzing. The measurement system was developed with a new Herriott cell and a heated gas cell realizing fast absorption measurements of high resolution, and combined with direct absorption and wavelenguh modulation based on tunable diode laser absorption spectroscopy at different temperatures. The lorentzian line shape is dominant at ambient temperature and pressure, and the estimated detectivity is approximately 0.225 x 10(-6) (SNR = 1) for the directed absorption spectroscopy, assuming a noise-equivalent absorbance of 1 x 10(-4). The heated cell

  6. Investigation fo Helicobacter Pylori prevalance in children with vitamine B12 deficiency

    OpenAIRE

    ishak abdurrahman isik; cahit baris erdur; ufuk Bozkurt Obuz; Nur Arslan

    2015-01-01

    Aim: Together with low intake, malabsorbtion is the most important factor causing vitamin B 12 (vit B 12) deficiency. Vitamin B 12 deficiency also has been shown to be associated with Helicobacter pylori (HP) gastritis in some studies. Aim of this study is to investigate the frequency of HP gastritis in patients with vit B 12 deficiency. Patients and methods: 24 patients (mean age: 15.6 +/- 1.3 years ) have been included the study. Serum vit B12 level has been measured by electrochemilumi...

  7. Genetic determinants of serum vitamin B12 and their relation to body mass index

    DEFF Research Database (Denmark)

    Allin, Kristine H; Friedrich, Nele; Pietzner, Maik

    2017-01-01

    (-4)). We found no support for a causal role of decreased serum vitamin B12 levels in obesity. However, our study suggests that FUT2, through its regulation of the cross-talk between gut microbes and the human host, might explain a part of the observational association between serum vitamin B12 and BMI....... for associations between (1) serum vitamin B12 levels and body mass index (BMI), (2) genetic variants and serum vitamin B12 levels, and (3) genetic variants and BMI. The effect of a genetically determined decrease in serum vitamin B12 on BMI was estimated by instrumental variable regression. Decreased serum...

  8. Vitamin B12 and folate levels in long-term vegans.

    Science.gov (United States)

    Bar-Sella, P; Rakover, Y; Ratner, D

    1990-06-01

    Serum vitamin B12, serum folate and red blood cell (RBC) folate levels were examined among 36 strict vegans of 5-35 years' duration. Vitamin B12 levels among the vegans were generally lower than in a control population. Most of the vegans had vitamin B12 values less than 200 pg/ml. RBC folate levels were normal but serum folate levels among the vegans were higher than among the controls. None of the vegans had any hematologic evidence of vitamin B12 deficiency, however four of them had neurologic complaints. Long-standing vegans should be monitored for vitamin B12 levels.

  9. 维生素B12在痤疮凹陷性瘢痕中的应用%Applicaion of Vitamin B12 in the Treatment of Facial Acne Imprint

    Institute of Scientific and Technical Information of China (English)

    漆平强; 王爽; 徐溪; 何燕; 颜娇; 颜佳; 刘洁; 陈义容

    2014-01-01

    目的:观察维生素B12在痤疮凹陷性瘢痕中的应用效果。方法:将于我院就诊的痤疮凹陷性瘢痕60例患者随机分为两组,对照组30例采用常规治疗,观察组30例在常规治疗的基础上加用维生素B12,观察比较两组痤疮凹陷性瘢痕情好转情况。结果:观察组好转率为90.0%,对照组好转率为66.7%,观察组疗效略优于对照组,但差异无统计学意义。结论:维生素B12可减少痤疮凹陷性瘢痕的形成。%Objective:To explore the application of Vitamin B12 in the treatment of facial acne imprint. Methods:Randomly dividing 60 acne patients into two groups and treated them with different methods. The control group was treated with regular method, and the observation group was added with Vitamin B12 based on the traditional treatment. And observing recovery condition of facial acne imprint. Results:The recovery rate in the observatio was 90.9%, and that in the control group was 66.7%. The recovery condition in the observation group was better than the control group. The difference had no statistical significance. Conclusion:Vitamin B12 plays an important role in facial acne prevention and treatment.

  10. Modification of oral absorption of oxyresveratrol using lipid based nanoparticles.

    Science.gov (United States)

    Sangsen, Yaowaporn; Wiwattanawongsa, Kamonthip; Likhitwitayawuid, Kittisak; Sritularak, Boonchoo; Wiwattanapatapee, Ruedeekorn

    2015-07-01

    The aim of this study was to develop and assess nanostructured lipid carriers (NLC) compared to solid lipid nanoparticles (SLN) for improving the oral bioavailability of oxyresveratrol (OXY). The OXY formulated as SLN (OXY-SLN) and NLC (OXY-NLC) were prepared by a high shear homogenization technique. The optimized OXY-NLC (NLC3) produced smaller nanoparticle sizes (96±0.9nm) than that of the OXY-SLN (108±0.3nm) with a homogeneous size distribution and a high zeta potential. The spherical NLC had a significantly higher efficiency for OXY entrapment (89±0.1%) and a better stability than the SLN after storage for 12 months at 4±2°C according to parameters such as smaller particles, greater zeta potential and a higher loading capacity (pSLN. The accumulated drug in an amorphous state in the NLC was also confirmed by powder X-ray diffraction (PXRD). The in vitro release profiles of the OXY-NLC showed a more sustained release compared to the SLN and unformulated OXY. The in vivo pharmacokinetic profiles implied enterohepatic recycling of OXY in the Wistar rat. Meanwhile, the oral absorption pattern of OXY was modified by both types of lipid nanoparticles. The SLN and NLC increased the relative bioavailability of OXY to 125% and 177%, respectively, compared with unformulated OXY. These findings indicated that NLC could be used as a potential carrier to improve the oral bioavailability of OXY.

  11. Characterization and Quantitation of Vitamin B12 Compounds in Various Chlorella Supplements.

    Science.gov (United States)

    Bito, Tomohiro; Bito, Mariko; Asai, Yusuke; Takenaka, Shigeo; Yabuta, Yukinori; Tago, Kazunori; Ohnishi, Masato; Mizoguchi, Toru; Watanabe, Fumio

    2016-11-16

    Vitamin B12 was determined and characterized in 19 dried Chlorella health supplements. Vitamin contents of dried Chlorella cells varied from B12-containing Chlorella tablets, respectively. In four Chlorella tablet types with high and moderate vitamin B12 contents, the coenzyme forms of vitamin B12 5'-deoxyadenosylcobalamin (approximately 32%) and methylcobalamin (approximately 8%) were considerably present, whereas the unnaturally occurring corrinoid cyanocobalamin was present at the lowest concentrations. The species Chlorella sorokiniana (formerly Chlorella pyrenoidosa) is commonly used in dietary supplements and did not show an absolute requirement of vitamin B12 for growth despite vitamin B12 uptake from the medium being observed. In further experiments, vitamin B12-dependent methylmalonyl-CoA mutase and methionine synthase activities were detected in cell homogenates. In particular, methionine synthase activity was significantly increased following the addition of vitamin B12 to the medium. These results suggest that vitamin B12 contents of Chlorella tablets reflect the presence of vitamin B12-generating organic ingredients in the medium or the concomitant growth of vitamin B12-synthesizing bacteria under open culture conditions.

  12. Coenzyme B12 can be produced by engineered Escherichia coli under both anaerobic and aerobic conditions.

    Science.gov (United States)

    Ko, Yeounjoo; Ashok, Somasundar; Ainala, Satish Kumar; Sankaranarayanan, Mugesh; Chun, Ah Yeong; Jung, Gyoo Yeol; Park, Sunghoon

    2014-12-01

    Coenzyme B12 (Vitamin B12 ) is one of the most complex biomolecules and an essential cofactor required for the catalytic activity of many enzymes. Pseudomonas denitrificans synthesizes coenzyme B12 in an oxygen-dependent manner using a pathway encoded by more than 25 genes that are located in six different operons. Escherichia coli, a robust and suitable host for metabolic engineering was used to produce coenzyme B12 . These genes were cloned into three compatible plasmids and expressed heterologously in E. coli BL21 (DE3). Real-time PCR, SDS-PAGE analysis and bioassay showed that the recombinant E. coli expressed the coenzyme B12 synthetic genes and successfully produced coenzyme B12 . However, according to the quantitative determination by inductively coupled plasma-mass spectrometry, the amount of coenzyme B12 produced by the recombinant E. coli (0.21 ± 0.02 μg/g cdw) was approximately 13-fold lower than that by P. denitrificans (2.75 ± 0.22 μg/g cdw). Optimization of the culture conditions to improve the production of coenzyme B12 by the recombinant E. coli was successful, and the highest titer (0.65 ± 0.03 μg/g cdw) of coenzyme B12 was obtained. Interestingly, although the synthesis of coenzyme B12 in P. denitrificans is strictly oxygen-dependent, the recombinant E. coli could produce coenzyme B12 under anaerobic conditions.

  13. Spectromicroscopy of boron in human glioblastomas following administration of Na2B12H11SH

    Science.gov (United States)

    Gilbert, B.; Perfetti, L.; Fauchoux, O.; Redondo, J.; Baudat, P.-A.; Andres, R.; Neumann, M.; Steen, S.; Gabel, D.; Mercanti, Delio; Ciotti, M. Teresa; Perfetti, P.; Margaritondo, G.; de Stasio, Gelsomina

    2000-07-01

    Boron neutron capture therapy (BNCT) is an experimental, binary treatment for brain cancer which requires as the first step that tumor tissue is targeted with a boron-10 containing compound. Subsequent exposure to a thermal neutron flux results in destructive, short range nuclear reaction within 10 μm of the boron compound. The success of the therapy requires than the BNCT agents be well localized in tumor, rather than healthy tissue. The MEPHISTO spectromicroscope, which performs microchemical analysis by x-ray absorption near edge structure (XANES) spectroscopy from microscopic areas, has been used to study the distribution of trace quantities of boron in human brain cancer tissues surgically removed from patients first administered with the compound Na2B12H11SH (BSH). The interpretation of XANES spectra is complicated by interference from physiologically present sulfur and phosphorus, which contribute structure in the same energy range as boron. We addressed this problem with the present extensive set of spectra from S, B, and P in relevant compounds. We demonstrate that a linear combination of sulfate, phosphate and BSH XANES can be used to reproduce the spectra acquired on boron-treated human brain tumor tissues. We analyzed human glioblastoma tissue from two patients administered and one not administered with BSH. As well as weak signals attributed to BSH, x-ray absorption spectra acquired from tissue samples detected boron in a reduced chemical state with respect to boron in BSH. This chemical state was characterized by a sharp absorption peak at 188.3 eV. Complementary studies on BSH reference samples were not able to reproduce this chemical state of boron, indicating that it is not an artifact produced during sample preparation or x-ray exposure. These data demonstrate that the chemical state of BSH may be altered by in vivo metabolism.

  14. Different Supplementation Regimes to Treat Perioperative Vitamin B12 Deficiencies in Bariatric Surgery: a Systematic Review.

    Science.gov (United States)

    Smelt, H J M; Pouwels, S; Smulders, J F

    2017-01-01

    Vitamin B12 dosage in multivitamin supplementation in the current literature is quite variable. There is no consensus about the optimal treatment of vitamin B12 deficiency. A systematic literature search on different supplementation regimes to treat perioperative vitamin B12 deficiencies in bariatric surgery was performed. The methodological quality of ten included studies was rated using the Newcastle Ottawa scale and ranged from moderate to good. The agreement between the reviewers was assessed with a Cohen's kappa (0.69). The current literature suggests that 350 μg oral vitamin B12 is the appropriate dose to correct low vitamin B12 levels in many patients. Further research must focus on a better diagnosis of a vitamin B12 deficiency, the optimal dose vitamin B12 supplementation, and clinical relevance next to biochemical data.

  15. Vitamin B12 and omega-3 fatty acids together regulate lipid metabolism in Wistar rats.

    Science.gov (United States)

    Khaire, Amrita; Rathod, Richa; Kale, Anvita; Joshi, Sadhana

    2015-08-01

    Our recent study indicates that maternal vitamin B12 and omega-3 fatty acid status influence plasma and erythrocyte fatty acid profile in dams. The present study examines the effects of prenatal and postnatal vitamin B12 and omega-3 fatty acid status on lipid metabolism in the offspring. Pregnant dams were divided into five groups: Control; Vitamin B12 deficient (BD); Vitamin B12 supplemented (BS); Vitamin B12 deficient group supplemented with omega-3 fatty acids (BDO); Vitamin B12 supplemented group with omega-3 fatty acids (BSO). The offspring were continued on the same diets till 3 month of age. Vitamin B12 deficiency increased cholesterol levels (pomega-3 fatty acids together play a crucial role in regulating the genes involved in lipid metabolism in adult offspring.

  16. Parallel computing and first-principles calculations: Applications to complex ceramics and Vitamin B12

    Science.gov (United States)

    Ouyang, Lizhi

    A systematic improvement and extension of the orthogonalized linear combinations of atomic orbitals method was carried out using a combined computational and theoretical approach. For high performance parallel computing, a Beowulf class personal computer cluster was constructed. It also served as a parallel program development platform that helped us to port the programs of the method to the national supercomputer facilities. The program, received a language upgrade from Fortran 77 to Fortran 90, and a dynamic memory allocation feature. A preliminary parallel High Performance Fortran version of the program has been developed as well. To be of more benefit though, scalability improvements are needed. In order to circumvent the difficulties of the analytical force calculation in the method, we developed a geometry optimization scheme using the finite difference approximation based on the total energy calculation. The implementation of this scheme was facilitated by the powerful general utility lattice program, which offers many desired features such as multiple optimization schemes and usage of space group symmetry. So far, many ceramic oxides have been tested with the geometry optimization program. Their optimized geometries were in excellent agreement with the experimental data. For nine ceramic oxide crystals, the optimized cell parameters differ from the experimental ones within 0.5%. Moreover, the geometry optimization was recently used to predict a new phase of TiNx. The method has also been used to investigate a complex Vitamin B12-derivative, the OHCbl crystals. In order to overcome the prohibitive disk I/O demand, an on-demand version of the method was developed. Based on the electronic structure calculation of the OHCbl crystal, a partial density of states analysis and a bond order analysis were carried out. The calculated bonding of the corrin ring of OHCbl model was coincident with the big open-ring pi bond. One interesting find of the calculation was

  17. Rapid determination of vitamin B12 concentration with a chemiluminescence lab on a chip.

    Science.gov (United States)

    Lok, Khoi Seng; Abdul Muttalib, Siti Zubaidah binte; Lee, Peter Peng Foo; Kwok, Yien Chian; Nguyen, Nam-Trung

    2012-07-07

    This paper reports a novel method for the rapid determination of vitamin B(12) concentration in a continuous-flow lab-on-a-chip system. This new method is based on luminol-peroxide chemiluminescence (CL) assays for the detection of cobalt(II) ions in vitamin B(12) molecules. The lab-on-a-chip device consisted of two passive micromixers acting as microreactors and a double spiral microchannel network serving as an optical detection region. This system could operate in two modes. In the first mode, samples are acidified and evaluated directly in the microchip. In the second mode, samples are treated externally by acidification prior to detection in the microchip. In the first mode, the linear range obtained was between 1.00 ng ml(-1) to 10 μg ml(-1), R(2) = 0.996, with a relative standard deviation (RSD) of 1.23 to 2.31% (n = 5) and a limit of detection (lod) of 0.368 pg ml(-1). The minimum sample volume required and the analytical time were 30 μl and 3.6 s, respectively. In the second mode, the linear range obtained was between 0.10 ng ml(-1) to 10 μg ml(-1), R(2) = 0.994, with the RSD of 0.90 to 2.32% (n = 6) and a lod of 0.576 pg ml(-1). The minimum sample and the analytical time required were 50 μl and 6 s, respectively. The lab on a chip working in mode II was successfully used for the determination of vitamin B(12) concentrations in nutritional supplemental tablets and hen egg yolks.

  18. A polar cap absorption model optimization based on the vertical ionograms analysis

    Science.gov (United States)

    Zaalov, N. Y.; Moskaleva, E. V.

    2016-11-01

    Space weather events significantly affect the high frequency (HF) radio wave propagation. The now-casting and forecasting of HF radio wave absorption is important for the HF communication industries. This paper assimilates vertical sounding data into an absorption model to improve its performance as a now-casting tool. The approach is a modification of the algorithm elaborated by Sauer and Wilkinson, which is based on the riometer data. The optimization is focused on accounting for short timescale variation of the absorption. It should be noted that the expression of the frequency dependence of absorption induced by the energetic particle precipitation employed in Sauer and Wilkinson model is based on the riometer data at frequencies of 20, 30, and 50 MHz. The approach suggested in this paper provides an opportunity for expanding the frequency dependence of the absorption for frequencies below 10 MHz. The simulation of the vertical ionograms in the polar cap region uses a computational model designed to overcome the high frequency wave propagation problem in high latitude of the Earth. HF radio wave absorption induced by solar UV illumination, X-ray flares and energetic particles precipitation is taken into consideration in our model. The absorption caused by the energetic particle precipitation is emphasized, because the study is focused on HF wave propagation in polar cap region. A comparison of observed and simulated vertical ionograms enables the coefficients, which relate absorption (day-time and night-time) to integral proton flux to be refined. The values of these coefficients determined from evaluation of the data recorded by any reliable ionosonde are valid for absorption calculation in high-latitude region.

  19. The causal roles of vitamin B12 and transcobalamin in prostate cancer: can Mendelian randomization analysis provide definitive answers?

    Science.gov (United States)

    Collin, Simon M; Metcalfe, Chris; Palmer, Tom M; Refsum, Helga; Lewis, Sarah J; Smith, George Davey; Cox, Angela; Davis, Michael; Marsden, Gemma; Johnston, Carole; Lane, J Athene; Donovan, Jenny L; Neal, David E; Hamdy, Freddie C; Smith, A David; Martin, Richard M

    2011-01-01

    Circulating vitamin B12 (cobalamin/B12) and total transcobalamin (tTC) have been associated with increased and reduced risk, respectively, of prostate cancer. Mendelian randomization has the potential to determine whether these are causal associations. We estimated associations of single nucleotide polymorphisms in B12-related genes (MTR, MTRR, FUT2, TCN2, TCN1, CUBN, and MUT) with plasma concentrations of B12, tTC, holo-transcobalamin, holo-haptocorrin, folate, and homocysteine and with prostate cancer risk in a case-control study (913 cases, 895 controls) nested within the UK-wide population-based ProtecT study of prostate cancer in men age 45-69 years. Instrumental variable (IV) analysis was used to estimate odds ratios for effects of B12 and tTC on prostate cancer. We observed that B12 was lower in men with FUT2 204G>A (rs492602), CUBN 758C>T (rs1801222) and MUT 1595G>A (rs1141321) alleles (PtrendG (rs1801198) allele (PtrendA and CUBN 758C>T were selected as instruments for B12; TCN2 776C>G for tTC. Conventional and IV estimates for the association of loge(B12) with prostate cancer were: OR=1.17 (95% CI 0.90-1.51), P=0.2 and OR=0.60 (0.16-2.15), P=0.4, respectively. Conventional and IV estimates for the association of loge(tTC) with prostate cancer were: OR=0.81 (0.54-1.20), P=0.3 and OR=0.41 (0.13-1.32), P=0.1, respectively. Confidence intervals around the IV estimates in our study were too wide to allow robust inference. Sample size estimates based on our data indicated that Mendelian randomization in this context requires much larger studies or multiple genetic variants that explain all of the variance in the intermediate phenotype. PMID:22199995

  20. Simulation of an absorption based solar cooling facility using a geothermal sink for heat rejection

    OpenAIRE

    Salgado, Rafael; Burguete, Ana; Rodríguez, María del Carmen; Rodríguez, Pedro

    2008-01-01

    An important issue of solar cooling facilities based on absorption cycles and sometimes not given the necessary attention is the recooling process of the absorber and condenser. This is critical in the overall behaviour of the facility because the condensation and absorption temperatures will affect the COP and cooling capacity of the chiller. Most of the time the recooling process is made by using a wet cooling tower in a closed loop through the absorber and condenser. The use of a wet cooli...

  1. Vitamin B12 and folic acid supplementation and plasma total homocysteine concentrations in pregnant Indian women with low B12 and high folate status.

    Science.gov (United States)

    Katre, Prachi; Bhat, Dattatray; Lubree, Himangi; Otiv, Suhas; Joshi, Suyog; Joglekar, Charudatta; Rush, Elaine; Yajnik, Chittaranjan

    2010-01-01

    Maternal vitamin B12 deficiency and hyperhomocysteinemia predict poor pregnancy outcome, foetal adiposity and insulin resistance. In India amongst practicing clinicians and policy makers there is little appreciation of widespread vitamin B12 deficiency. We investigated 163 (86 rural, 77 urban) pregnant women attending antenatal clinics in a rural health centre and a referral hospital in the city of Pune, at 17, 28, and 34 weeks gestation for vitamin supplements, and circulating concentrations of vitamin B12, folate, and total homocysteine. At enrolment 80% rural and 65% urban women had low vitamin B12 but only two rural women had low folate concentrations. During pregnancy 85% rural and 95% of urban women received folic acid; 12% rural and 84% urban women also received vitamin B12. In women receiving no supplementation (n=17) plasma vitamin B12 and folate did not change from 17 to 34 weeks gestation, but homocysteine increased (pHomocysteine concentrations at 34 weeks gestation in women receiving only folic acid (n=71, mean 8.4 (95% CI 7.8, 9.1) micromol/L) were comparable to the unsupplemented group (9.7 (7.3, 12.7), p=0.15), but women who received a total dose of >1000 microg of vitamin B12 up to 34 weeks (n=42, all with folic acid) had lower concentrations (6.7 (6.0, 7.4), phomocysteine concentration. In vitamin B12 insufficient, folate replete pregnant women, vitamin B12 supplementation is associated with a reduction of plasma total homocysteine concentration in late pregnancy.

  2. Performance of Numerical Boundary Condition based on Active Wave Absorption

    DEFF Research Database (Denmark)

    Troch, Peter; De Rouck, Julien; Frigaard, Peter

    2001-01-01

    The performance of a new active wave generating-absorbing boundary condition for a numerical model based on the Volume Of Fluid (VOF) method for tracking free surfaces is presented.......The performance of a new active wave generating-absorbing boundary condition for a numerical model based on the Volume Of Fluid (VOF) method for tracking free surfaces is presented....

  3. Folato, vitamina B12 e ferritina sérica e defeitos do tubo neural Folate, vitamin B12, serum ferritin and defects of the neural tube

    Directory of Open Access Journals (Sweden)

    Gizele Thame

    1998-09-01

    Full Text Available Objetivo: verificar os níveis de folatos, vitamina B12 e ferritina em pacientes cujos fetos apresentaram defeitos de tubo neural (DTN. O folato sangüíneo e a vitamina B12 atuam como cofatores para as enzimas envolvidas na biossíntese do DNA. A interrupção deste processo pode impedir o fechamento do tubo neural. A suplementação vitamínica contendo folato pode reduzir as taxas de ocorrência de defeitos de tubo neural, embora exista a preocupação de que esta prevenção possa mascarar a deficiência de vitamina B12. Métodos: dosagens de vitamina B12 e ferritina pelo método de enzimaimunoensaio com micropartículas e a dosagens de ácido fólico pelo método de captura iônica (IMx ABBOTT. Resultados: a porcentagem de gestantes com deficiência de vitamina B12 (níveis séricos Purpose: to determine folate, vitamin B12 and ferritin levels in patients whose fetuses presented neural-tube defects (NTD. Blood folate and vitamin B12 act as cofactors of enzymes involved in DNA biosynthesis. Interruption of this process may block neural-tube closing. Vitamin supplementation with folate may reduce occurrence rates and recurrence of NTD, although there is concern about the fact that this prevention may mask vitamin B12 deficiency. Methods: vitamin B12 and ferritin determinations by enzyme immunoassay with microparticles and folic acid determination using the ion capture method (IMx ABBOTT. Results: the percentage of pregnant women with vitamin B12 deficirncy (serum levels < 150 pg/ml was 11.8%. There was no case of folate deficiency (serum levels < 3.0 ng/ml and prevalence of pregnant women with iron store deficiency was 47.1% (serum levels < ng/mg. Conclusions: occording to the results obtained in this study (prevalence of 11.8% of vitamin B12 and 0% of folate deficient pregnant women we suggest that supplementation should be administered after serum vitamin B12 determination.

  4. 维生素B12滴眼液中维生素B12有关物质方法学研究

    Institute of Scientific and Technical Information of China (English)

    张媛媛

    2015-01-01

    目的:建立维生素B12滴眼液中维生素B12有关物质的检测方法.方法:高效液相色谱法,乙腈-0.05mol/l磷酸二氢钾溶液(17:83),用磷酸调节PH值至3.0.检测波长361nm.结果:本方法能有效检测出维生素B12的有关物质.

  5. 根据血清维生素B12水平测定值诊断维生素B12缺乏症

    Institute of Scientific and Technical Information of China (English)

    Vinod; Devalia; 颜淑敏(译)

    2006-01-01

    当患者出现血液系统、神经系统及神经精神系统异常时,血清维生素B12水平被用价是否存在维生素B12的缺乏。及早给予维生素B12补充治疗可阻止不可逆性神经系统病变和认知功能障碍的发生。

  6. Genetic Variation in Vitamin B-12 Content of Bovine Milk and Its Association with SNP along the Bovine Genome

    NARCIS (Netherlands)

    Rutten, M.J.M.; Bouwman, A.C.; Sprong, R.C.; Arendonk, van J.A.M.; Visker, M.H.P.W.

    2013-01-01

    Vitamin B-12 (also called cobalamin) is essential for human health and current intake levels of vitamin B-12 are considered to be too low. Natural enrichment of the vitamin B-12 content in milk, an important dietary source of vitamin B-12, may help to increase vitamin B-12 intake. Natural enrichment

  7. Correlations of Alzheimer disease with vitamin B12 and homocysteine%阿尔茨海默病与维生素 B12及同型半胱氨酸的相关性

    Institute of Scientific and Technical Information of China (English)

    李方明; 彭海

    2004-01-01

    BACKGROUND:The deficiency of vitamin B12 will lead to neurological disorder and affect the metabolism of central nervous system(CNS) and the whole body.The mechanism of filling up vitamin B12 in preventing and retarding the development of Alzheimer disease(AD) remains uncertain. OBJECTIVE:To explore the correlations of AD with serum vitamin B12,folate and plasma homocysteine(Hcy)and its mechanism of inducing AD. DESIGN:A non randomized control study based on diagnosis. SETTINGS and PARTICIPANTS:Thirty AD inpatients(AD group),admitted from October 2002 to May 2003 to the Affiliated Xiehe Hospital,Tongji Medical College,Huazhong University of Science and Technology,conformed to the probable AD standard of NINCDS- ADRDA.Thirty healthy normal persons who took the health examinaltion at the same time period were recruited to control group. INTERVENTIONS:Patients of the two groups were scored with mini mental state examination(MMSE).The concentration of serum vitamin B12 and folate were examined with the radioimmunoassay. Plasma Hcy was measured with fluorescence polarization immunoassay(FPIA).MAIN OUTCOME MEASURES:①differences of vitamin B12 level in the AD group and the control group.②differences of Hcy level in the AD group and the control group.③ the correlations of MMSE score with vitamin B12 and Hcy. RESULTS:The level of serum vitamin B12 in the AD group[(217.3 ± 134.2) pmol/L] was significantly lower than that of the control group[(313.6± 184.7) pmol/L].There was extremely significant difference between them(t=3.93,P 0.05).There was positive correlation between serum vitamin B12 and MMSE scores. CONCLUSION:The level of serum vitamin B12 of AD patients is related to the disorder of intelligence.%背景:维生素 B12缺乏会产生神经功能障碍,影响中枢神经系统及全身的代谢,补充维生素 B12对预防及延缓阿尔茨海默病( Alzheimer disease, AD)的发展作用机制尚不清楚. 目的 : 研究 AD与血清维生素 B12,叶酸及血

  8. Research on relationship of the occurrence of ischemic stroke with serum folic acid, platelet aggregation rate, homocysteine and vitamin B12%缺血性脑卒中的发生与血清叶酸、血小板聚集率、同型半胱氨酸和维生素B12的关系研究

    Institute of Scientific and Technical Information of China (English)

    王秀梅; 郝钦芳; 陈烨

    2011-01-01

    目的:探讨缺血性脑卒中患者血清叶酸( Folic Acid,FA)、血小板聚集率(Platelet Aggregation Rate,PAR)、同型半胱氨酸( Homocysteine,Hcy)和维生素B12(vitamin B12,VitB12)变化的原因及其关系.方法:选择缺血性脑卒中患者和健康对照组各60例,利用免疫法测其FA、PAR、Hcy和vitamin B12水平.结果:缺血性脑卒中患者体内FA水平偏低,PAR、VitB12和Hcy水平偏高,P<0.05;与缺血性脑卒中关系依次为FA>VitB12>PAR>Hcy,FA与PAR的相关关系r=0.006,P<0.01;HCY与PAR的相关关系r=0.03,P<0.05,FA与HCY的相关关系r=0.07.结论:缺血性脑卒中患者FA水平偏低,补充叶酸能降低PAR、改善HCY的氧化和VitB12的吸收,降低缺血性脑卒中的发生.%Objective: To explore the reason of changes and the interrelationships of serum Folic Acid (FA) , Homocysteine (Hcy) ,Platelet Aggregation Rate (PAR) and vitamin B12(VitB12) in ischaemic stroke patients. Methods: 60 ischemic stroke patients and 60 healthy controls were selected for concentration detection of FA, PAR, VitB12 and Hey by immune method. Results: FA level is low in ischemic stroke patients, while PAR, VitB12 and Hey level were high (P VitB12 > PAR > Hcy. The correlation between FA and PAR is r = 0.006, P < 0.01. The correlation between Hey and PAR is r = 0.03, P<0.05. The correlation between FA and Hey is r=0.07. Conclusion; FA level in ischemic stroke patients is low. Supplement of FA can reduce PAR, avoid Hcy oxidation, improve VitB12 absorption and reduce the occurrence of ischemic stroke.

  9. Transient Supersaturation Supports Drug Absorption from Lipid-Based Formulations for Short Periods of Time, but Ongoing Solubilization Is Required for Longer Absorption Periods.

    Science.gov (United States)

    Crum, Matthew F; Trevaskis, Natalie L; Pouton, Colin W; Porter, Christopher J H

    2017-02-06

    The current studies sought to explore the impact of drug supersaturation and precipitation during the dispersion and digestion of lipid-based formulations (LBFs), on in vivo absorption using a coupled in vitro digestion-in vivo perfusion absorption model. Fenofibrate absorption was evaluated from a number of LBFs with different solubilization and supersaturation capacities, and conditions at the absorptive membrane manipulated by changing perfusion conditions, intestine segment lengths, and by the conduct of experiments in the presence or absence of suspended/precipitated drug. LBF dispersion and digestion resulted in varying periods of supersaturation across the different formulations. Even fleeting (5-10 min) periods of supersaturation were able to drive flux across a perfused 10 cm intestinal segment for up to 60 min, although over longer infusion periods (60-80 min) flux dropped in the absence of ongoing drug solubilization and supersaturation. In contrast, the presence or absence of precipitated/suspended drug, had little impact on drug flux. When perfused intestinal segment lengths were extended, the role of initial supersaturation was attenuated and ongoing solubilization conditions became the primary driver of absorptive flux. The data suggest that for highly permeable drugs such as fenofibrate, a short period of supersaturation at the absorptive membrane may be sufficient to drive absorptive drug flux in spite of significant drug precipitation on formulation dispersion or digestion in vitro. In contrast, where longer periods of absorption are required, for example, at higher doses, the requirement for ongoing solubilization and supersaturation becomes more apparent.

  10. LDEF (Prelaunch), AO201 : Interplanetary Dust Experiment, Tray B12

    Science.gov (United States)

    1984-01-01

    LDEF (Prelaunch), AO201 : Interplanetary Dust Experiment, Tray B12 The prelaunch photograph shows the six (6) inch deep Interplanetary Dust Experiment (IDE) master control tray. The tray has three (3) mounting/cover plates elevated on fiberglass stand-offs to provide clearance and protection for hardware and electronics located underneath. The stand-offs also raise the plates to a level that minimizes shading of detectors by the tray sidewalls. The mounting plate located at the left hand end of the tray is populated with eighty (80) metaloxide-silicon (MOS) capacitor-type impact sensors and one (1) solar sensor that is located approximately in the center of the mounting plate. The IDE sensors are two (2) inch diameter MOS capacitor structures approximately 250 um thick. The detectors are formed by growing either 0.4um or 1.0um thick silicon oxide, SiO2, layer on the 250um thick, B-doped polished silicon wafer. The top metal contact, the visible surface, was formed by vapor deposition of 1000A of aluminum on the SiO2 surface. Aluminum was also vapor deposited on the backside to form the contact with the silicon substrate. Gold wires are bonded to the front and back aluminum layers for use in connecting the detectors to the circuits. The complete wafers, IDE detectors, are mounted on chromic anodized aluminum frames by bonding the detector backside to the aluminum frame with a space qualified RTV silicon adhesive, de-volatized RTV-511. The difference in colors of the detectors is caused by reflections in the metallized surfaces. A reflection of one of the technicians is visible in the three (3) rows of detector on the left hand side of the mounting plate. The solar sensor, located at the mounting plate center, consist of four (4) silicon solar cells connected in series and associated circuity bonded to an aluminum baseplate. The solar sensor registered each orbital sunrise independant of LDEF orientation at the time of sunrise. When IDE solar sensor data from the six

  11. 4-ethylphenyl-cobalamin impairs tissue uptake of vitamin B12 and causes vitamin B12 deficiency in mice.

    Directory of Open Access Journals (Sweden)

    Elena Mutti

    Full Text Available Coβ-4-ethylphenyl-cob(III alamin (EtPhCbl is an organometallic analogue of vitamin B12 (CNCbl which binds to transcobalamin (TC, a plasma protein that facilitates the cellular uptake of cobalamin (Cbl. In vitro assays with key enzymes do not convert EtPhCbl to the active coenzyme forms of Cbl suggesting that administration of EtPhCbl may cause cellular Cbl deficiency. Here, we investigate the in vivo effect of EtPhCbl in mice and its ability, if any, to induce Cbl deficiency. We show that EtPhCbl binds to mouse TC and we examined mice that received 3.5 nmol/24h EtPhCbl (n=6, 3.5 nmol/24h CNCbl (n=7 or NaCl (control group (n=5 through osmotic mini-pumps for four weeks. We analyzed plasma, urine, liver, spleen, submaxillary glands and spinal cord for Cbl and markers of Cbl deficiency including methylmalonic acid (MMA and homocysteine (tHcy. Plasma MMA (mean±SEM was elevated in animals treated with EtPhCbl (1.01±0.12 µmol/L compared to controls (0.30±0.02 µmol/L and CNCbl (0.29±0.01 µmol/L treated animals. The same pattern was observed for tHcy. Plasma total Cbl concentration was higher in animals treated with EtPhCbl (128.82±1.87 nmol/L than in CNCbl treated animals (87.64±0.93 nmol/L. However, the organ levels of total Cbl were significantly lower in animals treated with EtPhCbl compared to CNCbl treated animals or controls, notably in the liver (157.07±8.56 pmol/g vs. 603.85±20.02 pmol/g, and 443.09±12.32 pmol/g, respectively. Differences between the three groups was analysed using one-way ANOVA and, Bonferroni post-hoc test. EtPhCbl was present in all tissues, except the spinal cord, accounting for 35-90% of total Cbl. In conclusion, treatment with EtPhCbl induces biochemical evidence of Cbl deficiency. This may in part be caused by a compromised tissue accumulation of Cbl.

  12. 4-ethylphenyl-cobalamin impairs tissue uptake of vitamin B12 and causes vitamin B12 deficiency in mice.

    Science.gov (United States)

    Mutti, Elena; Ruetz, Markus; Birn, Henrik; Kräutler, Bernhard; Nexo, Ebba

    2013-01-01

    Coβ-4-ethylphenyl-cob(III) alamin (EtPhCbl) is an organometallic analogue of vitamin B12 (CNCbl) which binds to transcobalamin (TC), a plasma protein that facilitates the cellular uptake of cobalamin (Cbl). In vitro assays with key enzymes do not convert EtPhCbl to the active coenzyme forms of Cbl suggesting that administration of EtPhCbl may cause cellular Cbl deficiency. Here, we investigate the in vivo effect of EtPhCbl in mice and its ability, if any, to induce Cbl deficiency. We show that EtPhCbl binds to mouse TC and we examined mice that received 3.5 nmol/24h EtPhCbl (n=6), 3.5 nmol/24h CNCbl (n=7) or NaCl (control group) (n=5) through osmotic mini-pumps for four weeks. We analyzed plasma, urine, liver, spleen, submaxillary glands and spinal cord for Cbl and markers of Cbl deficiency including methylmalonic acid (MMA) and homocysteine (tHcy). Plasma MMA (mean±SEM) was elevated in animals treated with EtPhCbl (1.01±0.12 µmol/L) compared to controls (0.30±0.02 µmol/L) and CNCbl (0.29±0.01 µmol/L) treated animals. The same pattern was observed for tHcy. Plasma total Cbl concentration was higher in animals treated with EtPhCbl (128.82±1.87 nmol/L) than in CNCbl treated animals (87.64±0.93 nmol/L). However, the organ levels of total Cbl were significantly lower in animals treated with EtPhCbl compared to CNCbl treated animals or controls, notably in the liver (157.07±8.56 pmol/g vs. 603.85±20.02 pmol/g, and 443.09±12.32 pmol/g, respectively). Differences between the three groups was analysed using one-way ANOVA and, Bonferroni post-hoc test. EtPhCbl was present in all tissues, except the spinal cord, accounting for 35-90% of total Cbl. In conclusion, treatment with EtPhCbl induces biochemical evidence of Cbl deficiency. This may in part be caused by a compromised tissue accumulation of Cbl.

  13. Metabolic vitamin B12 deficiency: a missed opportunity to prevent dementia and stroke.

    Science.gov (United States)

    Spence, J David

    2016-02-01

    The purpose of this narrative review is to highlight insights into the importance and frequency of metabolic vitamin B12 (B12) deficiency, reasons why it is commonly missed, and reasons for the widespread but mistaken belief that treatment of B12 deficiency does not prevent stroke or improve cognitive function. Metabolic B12 deficiency is common, being present in 10%-40% of the population; is frequently missed; is easily treated; and contributes importantly to cognitive decline and stroke in older people. Measuring serum B12 alone is not sufficient for diagnosis; it is necessary to measure holotranscobalamin or functional markers of B12 adequacy such as methylmalonic acid or plasma total homocysteine. B-vitamin therapy with cyanocobalamin reduces the risk of stroke in patients with normal renal function but is harmful (perhaps because of thiocyanate accumulation from cyanide in cyanocobalamin) in patients with renal impairment. Methylcobalamin may be preferable in renal impairment. B12 therapy slowed gray matter atrophy and cognitive decline in the Homocysteine and B Vitamins in Cognitive Impairment Trial. Undiagnosed metabolic B12 deficiency may be an important missed opportunity for prevention of dementia and stroke; in patients with metabolic B12 deficiency, it would be prudent to offer inexpensive and nontoxic supplements of oral B12, preferably methylcobalamin or hydroxycobalamin. Future research is needed to distinguish the effects of thiocyanate from cyanocobalamin on hydrogen sulfide, and effects of treatment with methylcobalamin on cognitive function and stroke, particularly in patients with renal failure.

  14. Vitamin B12 deficiency in resettled Bhutanese refugees--United States, 2008-2011.

    Science.gov (United States)

    2011-03-25

    Since 2008, approximately 30,000 Bhutanese refugees have been resettled in the United States. Routine medical examinations of refugees after arrival in resettlement states indicated hematologic and neurologic disorders caused by vitamin B12 deficiency. These cases were reported by examining physicians and state health departments to CDC, which initiated an investigation. This report summarizes the results of that investigation. Sera from overseas medical examinations, postarrival examinations in three state health departments (Minnesota, Utah, and Texas), and medical records and interviews at a health clinic in St. Paul, Minnesota, were evaluated. Vitamin B12 deficiency, defined as serum vitamin B12 concentration refugees screened for vitamin B12 deficiency at the St. Paul clinic. Although the deficiencies might be multifactorial, the main cause is thought to be the diet consumed by these refugees for nearly two decades in Nepal, which lacked meat, eggs, and dairy products, the major dietary sources of vitamin B12. Additionally, infection with Helicobacter pylori might play a role. Clinicians should be aware of the risk for vitamin B12 deficiency in Bhutanese refugees. All Bhutanese refugees should be given nutrition advice and should receive supplemental vitamin B12 upon arrival in the United States. In addition, refugees with clinical manifestations suggestive of deficiency should be tested for adequate serum vitamin B12 concentrations and, if found to have a B12 deficiency, screened for underlying causes, treated with parenteral vitamin B12 or high-dose oral supplements, and evaluated for response to therapy.

  15. Vitamin B12-loaded solid lipid nanoparticles as a drug carrier in cancer therapy.

    Science.gov (United States)

    Genç, Lütfi; Kutlu, H Mehtap; Güney, Gamze

    2015-05-01

    Nanostructure-mediated drug delivery, a key technology for the realization of nanomedicine, has the potential to improve drug bioavailability, ameliorate release deviation of drug molecules and enable precision drug targeting. Due to their multifunctional properties, solid lipid nanoparticles (SLNs) have received great attention of scientists to find a solution to cancer. Vitamin supplements may contribute to a reduction in the risk of cancer. Vitamin B12 has several characteristics that make it an attractive entity for cancer treatment and possible therapeutic applications. The aim of this study was to produce B12-loaded SLNs (B12-SLNs) and determine the cytotoxic effects of B12-SLNs on H-Ras 5RP7 and NIH/3T3 control cell line. Results obtained by MTT assay, transmission electron and confocal microscopy showed that B12-loaded SLNs are more effective than free vitamin B12 on cancer cells. In addition, characterization studies indicate that while the average diameter of the B12 was about 650 nm, B12-SLNs were about 200 nm and the drug release efficiency of vit. B12 by means of SLNs increased up to 3 h. These observations point to the fact that B12-SLNs could be used as carrier systems due to the therapeutic effects on cancer.

  16. Association of B12 deficiency and clinical neuropathy with metformin use in type 2 diabetes patients

    Directory of Open Access Journals (Sweden)

    A K Singh

    2013-01-01

    Full Text Available Context: Long-term metformin use has been hypothesized to cause B12 deficiency and neuropathy in Type 2 diabetes patients. However, there is a paucity of Indian data regarding the same. Aim: To compare the prevalence of B12 deficiency and peripheral neuropathy in patients with Type 2 diabetes mellitus treated with or without metformin. Materials and Methods: We recruited patients with Type 2 diabetes and divided them into metformin exposed and nonmetformin exposed groups. We measured baseline demographic variables like age, sex, vegetarian status, and HbA1c levels in both groups. We compared vitamin B12 levels and severity of peripheral neuropathy (using Toronto Clinical Scoring System (TCSS in both groups. Definite B12 deficiency was defined as B12 <150 pg/ml and possible B12 deficiency as <220 pg/ml. The difference in vitamin B12 levels and TCSS was calculated in both groups using independent samples t-test. Spearman′s rank correlation between cumulative metformin use and B12 level was calculated. Odds ratio of vitamin B12 deficiency in metformin exposed group was also estimated. Results: Mean serum B12 levels was significantly lower in metformin exposed group (n=84 compared with nonmetformin exposed group (n=52 (410±230.7 versus 549.2±244.7, P=0.0011. Mean neuropathy score was significantly higher in metformin exposed group. (5.72±2.04 versus 4.62±2.12, P=0.0064. Odds ratio for possible B12 deficiency was 4.45 (95% CI 1.24-15.97. There was significant negative correlation between cumulative metformin dose and vitamin B12 level (r=−0.68, P<0.0001. Conclusion: Metformin use is associated with vitamin B12 deficiency and clinical neuropathy in Type 2 diabetes patients.

  17. Relation of Vitamin B12 Levels to Bone Mineral Density of Postmenopausal Women - Original Investigation

    Directory of Open Access Journals (Sweden)

    Nur Kesiktaş

    2009-04-01

    Full Text Available Aim: Although vitamin B12 (vit-B12 is known to influence the hemopoeitic and nervous systems, little is known about the skeletal effects of vit-B12. Researchs that demonstrated an association between serum vitamin B-12 concentration and osteoblastic function and its’ role in DNA synthesis, which suggesting a relationship between osteoporosis, this randomized controlled trial were planned. Material and Methods: Vit-B12 levels of 740 patients aged between 50-65 years, who were applied to our outpatient clinic because of chronic low back pain were examined and divided with vitamin B-12 levels over or below 400 pg/ml. 26 participant who met all inclusion criteria with vit-B12 level below 400pg/ml were assigned to case group. Among the patients that vit-B12 levels were over 400pg/ml, 20 participants were randomly selected to control group. Bone mineral density (BMD, biochemical measurements, causes of osteoporosis and vit-B12 defiencies were investigated. A computer program was used for statistic evaluation. Results: There was not statistically significant difference between BMD’s of case and control groups (p>0.05. When the vit-B12 levels were grouped with over 400 pg/ml, below 200 pg/ml and between 200-400 pg/ml, osteodensimetric examinations of femur neck BMD (p<0.05 were achieved statistically significant difference. Conclusion: The results of this trial highlight an association of vitamin B-12 status with osteoporosis. Vit-B12 defiency is an easy and cheap treatable condition so that reason we suggest that levels of vit-B12 should be investigated. (From the World of Osteoporosis 2009;15:1-6

  18. Absorption properties of GaAsBi based p-i-n heterojunction diodes

    Science.gov (United States)

    Zhou, Zhize; Mendes, Danuta F.; Richards, Robert D.; Bastiman, Faebian; David, John PR

    2015-09-01

    The absorption properties of GaAsBi have been investigated using GaAsBi based p-i-n diodes with different bismuth compositions (˜2.1 and ˜3.4%). The absorption behaviour of GaAsBi as a function of incident photon energy above the band gap follows that of a direct band gap material. With increasing bismuth content, the absorption of photons with energy lower than the band gap in GaAsBi is enhanced, probably due to localized states caused by Bi-related defects. A simplified analysis has been undertaken on the behaviour of absorption as a function of bias voltage. By undertaking photoresponsivity measurements as a function of reverse bias, the background doping type and the minority carriers diffusion lengths in GaAsBi have been determined.

  19. Thickness Optimization for Petroleum Coke in Microwave Dehydrating Based on the Analysis of Dynamic Absorption Efficiency

    Science.gov (United States)

    Shang, Xiaobiao; Chen, Junruo; Peng, Jinhui; Chen, Hua; Zhang, Weifeng; Guo, Shenghui; Chen, Guo

    2015-07-01

    An analytical approach is proposed to optimize the thickness of petroleum coke for achieving maximum microwave power absorption in microwave heating based on analysis of reflection loss (RL). The microwave RL of the petroleum coke layer was studied over the moisture content range of 1%-5% at 20 °C and the petroleum coke (10% moisture content) in the temperature range of 20 to 100 °C at 2.45 GHz. The results show that RL depends sensitively on the thickness of the petroleum coke and the absorption peak shifts towards a larger thickness as the moisture content of the petroleum coke increases. There exists a matching thickness corresponding to the maximum microwave absorption, the maximum absorbing peak decreases when the thickness of petroleum coke exceeds the matching thickness. We also show that the absorption peak is found to move towards a smaller thickness region with increasing petroleum coke temperature.

  20. Tunable angle absorption of hyperbolic metamaterials based on plasma photonic crystals

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Zheng; Ning, Renxia, E-mail: nrxxiner@hsu.edu.cn; Xu, Yuan [College of Information Engineering, Huangshan University, Huangshan 245041 (China); Bao, Jie [College of Mechanical and Electrical Engineering, Huangshan University, Huangshan 245041 (China)

    2016-06-15

    We present the design of a multilayer structure of hyperbolic metamaterials based on plasma photonic crystals which composed of two kinds of traditional dielectric and plasma. The relative permittivity of hyperbolic metamaterials has been studied at certain frequency range. The absorption and reflection of the multilayer period structure at normal and oblique incident have been investigated by the transfer matrix method. We discussed that the absorption is affected by the thickness of material and the electron collision frequency γ of the plasma. The results show that an absorption band at the low frequency can be obtained at normal incident angle and another absorption band at the high frequency can be found at a large incident angle. The results may be applied by logical gate, stealth, tunable angle absorber, and large angle filter.

  1. Intelligent predicting approach of peritoneal fluid absorption rate based-on neural network

    Institute of Scientific and Technical Information of China (English)

    Mei ZHANG; Yueming HU; Tao WANG

    2003-01-01

    This paper addresses the important intelligent predicting problem of peritoneal absorption rate in the peritoneal dialysis treament process of renal failure. As the index of dialysis adequacy, KT/V and Ccr are widely used and accepted. However,growing evidence suggests that the fluid balance may play a critical role in dialysis adequacy and patient outcome. Peritoneal fluid absorption decreases the peritoneal fluid removal. Understanding the peritoneal fluid absorption rate will help clinicians to opthnize the dialysis dwell time. The neural network approach is applied to the prediction of peritoneal absorption rate. Compared with multivariable regression method, the experimental results showed that neural network method has an advantage over multivariable regression. The application of this predicting method based-on neural network in clinic is instructive.

  2. Zinc absorption in humans from meals based on rye, barley, oatmeal, triticale and whole wheat

    Energy Technology Data Exchange (ETDEWEB)

    Sandstroem, B.A.; Almgren, A.; Kivistoe, B.C.; Cederblad, A.

    1987-11-01

    The absorption of zinc from meals based on 60 g of rye, barley, oatmeal, triticale or whole wheat was studied by use of extrinsic labelling with /sup 65/Zn and measurement of the whole-body retention of the radionuclide. The cereals were prepared in the form of bread or porridge and were served with 200 mL of milk. The oatmeal flakes were also served without further preparation. The absorption of zinc was negatively correlated to the phytic acid content of the meal with the highest absorption, 26.8 +/- 7.4%, from the rye bread meal containing 100 mumol of phytic acid and the lowest, 8.4 +/- 1.0%, from oatmeal porridge with a phytic acid content of 600 mumol. It is concluded that food preparation that decreases the phytic acid content improves zinc absorption.

  3. Zinc absorption in humans from meals based on rye, barley, oatmeal, triticale and whole wheat.

    Science.gov (United States)

    Sandström, B; Almgren, A; Kivistö, B; Cederblad, A

    1987-11-01

    The absorption of zinc from meals based on 60 g of rye, barley, oatmeal, triticale or whole wheat was studied by use of extrinsic labelling with 65Zn and measurement of the whole-body retention of the radionuclide. The cereals were prepared in the form of bread or porridge and were served with 200 mL of milk. The oatmeal flakes were also served without further preparation. The absorption of zinc was negatively correlated to the phytic acid content of the meal with the highest absorption, 26.8 +/- 7.4%, from the rye bread meal containing 100 mumol of phytic acid and the lowest, 8.4 +/- 1.0%, from oatmeal porridge with a phytic acid content of 600 mumol. It is concluded that food preparation that decreases the phytic acid content improves zinc absorption.

  4. The Online Morphology Control and Dynamic Studies on Improving Vitamin B12 Production by Pseudomonas denitrificans with Online Capacitance and Specific Oxygen Consumption Rate.

    Science.gov (United States)

    Wang, Ze-Jian; Shi, Hui-Lin; Wang, Ping

    2016-07-01

    The relationship between the morphological character of Pseudomonas denitrificans and vitamin B12 synthesis based on real-time capacitance measurement and online specific oxygen consumption rate (Q O2) control was established for enhancing vitamin B12 production. Results demonstrated that the threshold Q O2 value lower than 2.0 mmol/gDCW/l would greatly stimulate the state transfer from the cell number growth phase to the cell elongation phase and promote rapid vitamin B12 biosynthesis, while the vitamin B12 biosynthesis rate could also be inhibited when the rate of cell's length-to-width ratio (ratio-LW) was higher than 10:1. Furthermore, the optimal morphology controlling strategy was achieved based on online Q O2 control, which increases the appropriate active cell numbers at the former phase, and then control the elongation of ratio-LW no more than 10:1 at the vitamin B12 biosynthesis phase. The maximal vitamin B12 production reached 239.7 mg/l at 168 h, which was improved by 14.7 % compared with the control (208 mg/l). This online controlling strategy would be effectively applied for improving industrial vitamin B12 fermentation.

  5. Pengaruh asupan Fe, vitamin A, vitamin B12, dan vitamin C terhadap kadar hemoglobin pada remaja vegan

    Directory of Open Access Journals (Sweden)

    Damayanti Siallagan

    2016-10-01

    Full Text Available Background: Vegan has become a diet that started to be many people's choice. Low intake of iron and vitamin B12 is factors that can cause anemia in vegan. On the other side vegans often consume vegetables and fruits that contained high of vitamin A and vitamin C which helps the absorption of iron, that can help prevent anemia. Objective: The purpose of the research know the effect of the intake of iron, vitamin A, vitamin B12, vitamin C on hemoglobin (Hblevels in young Buddhist vegan Pusdiklat Maitreyawira. Method: This research uses cross-sectional design. The population in this study are all adolescent vegan in the Buddhist Pusdiklat Maitreyawira. Samples in this study were 31 peoples. Independent variable is an intake of iron, vitamin A, vitamin B12, and vitamin C was obtained by SQ-FFQ, while the dependent variable was Hb with hemoglobin testing system quick-check set. Analysis of the data in this study using Pearson correlation and multiple linear regression. Results: There is a relationship intake of iron (p=0,000, vitamin B12 (p=0,037, and vitamin C (p=0,000 to Hb level of adolescent vegan in Buddhist Pusdiklat Maitreyawira, there is no relationship intake of vitamin A with a Hb level of adolescent vegan (p=0,220. The result of multivariate analysis using multiple regression analysis of the variables that most influence haemoglobin levels of adolescent vegan are the intake of iron and vitamin C. Each increase of 1 mg Fe intake will increase the Hb concentration as much as 0.013 g/dl and increase of 1 mg of vitamin C intake will increase Hb levels as much as 0.002 g/dl. Conclusion: Iron and vitamin C intake is the most influence factors to hemoglobin levels of adolescent vegan in Buddhist Pusdiklat Maitreyawira.

  6. 维生素B12的研究及其进展%Research Advance in Vitamin B12 and Its Application

    Institute of Scientific and Technical Information of China (English)

    罗祎; 郝常明

    2002-01-01

    本文对维生素B12的生理特性、产生菌、生物合成途径,以及发酵生产和测定方法进行了详尽的阐述,并对目前维生素B12发酵生产面临的问题及前景作了分析和预测.

  7. 维生素B12对抑郁症的辅助治疗%Vitamin B12 as Adjunctive Therapy in Patients with Major Depressive Disorder

    Institute of Scientific and Technical Information of China (English)

    杜春燕; 赵约翰; 徐广军

    2014-01-01

    目的:观察抑郁症患者血清维生素B12水平,探讨抗抑郁剂合并维生素B12治疗维生素B12缺乏抑郁症的疗效及安全性。方法对400名抑郁症患者进行血清维生素B12浓度测查,将筛查出的维生素B12缺乏的抑郁症患者70例,随机分为两组,各35例。对照组根据病情口服西酞普兰20~40 mg/次,每日1次,治疗8周;研究组根据病情口服西酞普兰20~40 mg/次,每日1次,同时合并使用维生素B12,治疗8周。研究组及对照组治疗前后1,2,4,8周末分别进行汉密尔顿抑郁量表( HAMD)评定;治疗后1,2,4,8周末分别评定副反应量表(TESS);治疗前及治疗后4,8周末分别查血清维生素B12浓度。结果抑郁症患者血清维生素B12平均水平(359.7±183.2)pg/ml,维生素B12缺乏发生率为19.5%,研究组与对照组第1周末汉密尔顿抑郁量表评分差异无显著性(P>0.05),治疗第2,4、8周末有显著性差异(P<0.01),研究组有效率为94.3%,对照组为74.3%,两组差异有显著性(P<0.01),血清维生素B12浓度治疗后4,8周末有显著性差异(P<0.01),且研究组汉密尔顿抑郁量表评分与血清维生素B12浓度负相关。两组不良反应均较轻微,TESS评分比较差异无显著性(P>0.05)。结论抑郁症患者血清维生素B12平均水平较正常明显降低,维生素B12缺乏发生率高,维生素B12辅助抗抑郁剂治疗可明显提高疗效,且不增加不良反应。%Objective To observe serum vitamin B 12 levels in patients with depression and explore the curative effects and safety of antidepressant combined with vitamine B 12 in the treatment of depression with vitamin B 12 deficiency.Methods Serum vitamin B12 lev-els in 400 patients with major depressive disorder were determined at baseline .70 depressive patients with vitamin B 12 deficiency were randomly divided into research

  8. Enhancement Factors in Ozone Absorption Based on the Surface Renewal Model and its Application

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Based on the Danckwerts surface renewal model, a simple explicit expression of theenhancement factor in ozone absorption with a first order ozone self-decomposition and parallel secondorder ozonation reactions has been derived. The results are compared with our previous work based onthe film theory. The 2,4-dichlorophenol destruction rate by ozonation is predicted using the enhancementfactor model in this paper.

  9. In vivo application of chitosan to improve bioavailability of cyanocobalamin, a form of vitamin B12, following intraintestinal administration in rats.

    Science.gov (United States)

    Goto, Yuko; Masuda, Ayumi; Aiba, Tetsuya

    2015-04-10

    The effect of chitosan on the intestinal absorption of cyanocobalamin (VB12), a stable form of vitamin B12, was investigated in vivo in rats, with the aim of improving the oral bioavailability of VB12 for anemia treatment in patients with gastrectomy. The bioavailability was evaluated based on the plasma concentration profile of VB12 following intraintestinal administration of the VB12 solution containing chitosan at various concentrations. The bioavailability of VB12 was 0.6±0.2% when the chitosan-free VB12 solution was administered, while it increased to 10.5±3.3% when chitosan was dissolved in the VB12 solution at a concentration of 1%. The bioavailability of VB12 increases with the chitosan concentration, in which chitosan seems to augment the amount of VB12 absorbed without affecting the absorption rate constant of VB12. It was also shown that the bioavailability of VB12 does not increase further when the degree of chitosan deacetylation is increased from 83 to 100% by substitutively employing the fully deacetylated chitosan. These findings suggest that the oral administration of VB12 with readily available chitosan may be a practical approach for anemia treatment in patients with gastrectomy. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. 可改善维生素B12吸收的Eligen技术

    Institute of Scientific and Technical Information of China (English)

    范丽珠(摘)

    2008-01-01

    Emisphere Technologies报告,采用其Eligen配方技术能改善口服维生素B12的生物利用度。Eligen B12产品(I)可使需要补充维生素B12的患者避免多次注射或口服大剂量。

  11. Prevalence of pernicious anemia in patients with macrocytic anemia and low serum B12

    OpenAIRE

    2014-01-01

    Objective: The current research evaluated the prevalence of pernicious anemia (PA) in patients with macrocytic anemia (high MCV) and low serum B12 in Riyadh. Methods: Blood testing was done in 77 patients (males: 45.5%, females: 54.5%) with macrocytic anemia; 84 patients; (males: 23.8%, females: 76.2%) with low serum B12 and 30 healthy subjects. Complete blood count, differential count, folic acid, vitamin B12, intrinsic factor, gastric parietal cell antibodies and holotranscobalamin II were ...

  12. Infection Susceptibility in Gastric Intrinsic Factor (Vitamin B12-Defective Mice Is Subject to Maternal Influences

    Directory of Open Access Journals (Sweden)

    Lynda Mottram

    2016-06-01

    Full Text Available Mice harboring a mutation in the gene encoding gastric intrinsic factor (Gif, a protein essential for the absorption of vitamin B12/cobalamin (Cbl, have potential as a model to explore the role of vitamins in infection. The levels of Cbl in the blood of Giftm1a/tm1a mutant mice were influenced by the maternal genotype, with offspring born to heterozygous (high Cbl, F1 mothers exhibiting a significantly higher serum Cbl level than those born to homozygous (low Cbl, F2 equivalents. Low Cbl levels correlated with susceptibility to an infectious challenge with Salmonella enterica serovar Typhimurium or Citrobacter rodentium, and this susceptibility phenotype was moderated by Cbl administration. Transcriptional and metabolic profiling revealed that Cbl deficient mice exhibited a bioenergetic shift similar to a metabolic phenomenon commonly found in cancerous cells under hypoxic conditions known as the Warburg effect, with this metabolic effect being exacerbated further by infection. Our findings demonstrate a role for Cbl in bacterial infection, with potential general relevance to dietary deficiency and infection susceptibility.

  13. Tunable absorption in graphene-based hyperbolic metamaterials for mid-infrared range

    Energy Technology Data Exchange (ETDEWEB)

    Ning, Renxia [College of Information Engineering, Huangshan University, Huangshan 245041,China (China); Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Liu, Shaobin, E-mail: plrg@nuaa.edu.cn [Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Zhang, Haifeng; Bian, Borui; Kong, Xiangkun [Key Laboratory of Radar Imaging and Microwave Photonics, Ministry of Education, College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

    2015-01-15

    Tunable absorption in periodic structure composed of graphene-based hyperbolic metamaterials (GHMMs) and isotropic medium is investigated by the transfer matrix method. The parallel part for relative permittivity of GHMMs consisting of monolayer graphene and conventional dielectric can be tuned by the chemical potential and dielectric layer thickness. The real part of the group index of GHMMs is insensitive to incident angle at the required frequency and the absorption of the periodic structure with GHMMs can be obtained nearly 100% at 22.4 terahertz (THz). The absorption peak of this frequency is almost uniform for both transverse electric (TE) and transverse magnetic (TE) polarizations. However, a new absorption peak can be observed incident angle is larger than 40 degree for TM polarization from 10 to 30 THz. The research results show that the absorption is insensitive to electromagnetic polarization at certain frequency. A new absorption peak can be found with TM polarization in low frequency region. These novel and effective GHMMs can replace metallic thin films as polarizing beam splitter for future optoelectronic applications.

  14. Tunable absorption in graphene-based hyperbolic metamaterials for mid-infrared range

    Science.gov (United States)

    Ning, Renxia; Liu, Shaobin; Zhang, Haifeng; Bian, Borui; Kong, Xiangkun

    2015-01-01

    Tunable absorption in periodic structure composed of graphene-based hyperbolic metamaterials (GHMMs) and isotropic medium is investigated by the transfer matrix method. The parallel part for relative permittivity of GHMMs consisting of monolayer graphene and conventional dielectric can be tuned by the chemical potential and dielectric layer thickness. The real part of the group index of GHMMs is insensitive to incident angle at the required frequency and the absorption of the periodic structure with GHMMs can be obtained nearly 100% at 22.4 terahertz (THz). The absorption peak of this frequency is almost uniform for both transverse electric (TE) and transverse magnetic (TE) polarizations. However, a new absorption peak can be observed incident angle is larger than 40 degree for TM polarization from 10 to 30 THz. The research results show that the absorption is insensitive to electromagnetic polarization at certain frequency. A new absorption peak can be found with TM polarization in low frequency region. These novel and effective GHMMs can replace metallic thin films as polarizing beam splitter for future optoelectronic applications.

  15. A Novel Acoustic Sensor Approach to Classify Seeds Based on Sound Absorption Spectra

    Directory of Open Access Journals (Sweden)

    Ole Green

    2010-11-01

    Full Text Available A non-destructive and novel in situ acoustic sensor approach based on the sound absorption spectra was developed for identifying and classifying different seed types. The absorption coefficient spectra were determined by using the impedance tube measurement method. Subsequently, a multivariate statistical analysis, i.e., principal component analysis (PCA, was performed as a way to generate a classification of the seeds based on the soft independent modelling of class analogy (SIMCA method. The results show that the sound absorption coefficient spectra of different seed types present characteristic patterns which are highly dependent on seed size and shape. In general, seed particle size and sphericity were inversely related with the absorption coefficient. PCA presented reliable grouping capabilities within the diverse seed types, since the 95% of the total spectral variance was described by the first two principal components. Furthermore, the SIMCA classification model based on the absorption spectra achieved optimal results as 100% of the evaluation samples were correctly classified. This study contains the initial structuring of an innovative method that will present new possibilities in agriculture and industry for classifying and determining physical properties of seeds and other materials.

  16. A novel acoustic sensor approach to classify seeds based on sound absorption spectra.

    Science.gov (United States)

    Gasso-Tortajada, Vicent; Ward, Alastair J; Mansur, Hasib; Brøchner, Torben; Sørensen, Claus G; Green, Ole

    2010-01-01

    A non-destructive and novel in situ acoustic sensor approach based on the sound absorption spectra was developed for identifying and classifying different seed types. The absorption coefficient spectra were determined by using the impedance tube measurement method. Subsequently, a multivariate statistical analysis, i.e., principal component analysis (PCA), was performed as a way to generate a classification of the seeds based on the soft independent modelling of class analogy (SIMCA) method. The results show that the sound absorption coefficient spectra of different seed types present characteristic patterns which are highly dependent on seed size and shape. In general, seed particle size and sphericity were inversely related with the absorption coefficient. PCA presented reliable grouping capabilities within the diverse seed types, since the 95% of the total spectral variance was described by the first two principal components. Furthermore, the SIMCA classification model based on the absorption spectra achieved optimal results as 100% of the evaluation samples were correctly classified. This study contains the initial structuring of an innovative method that will present new possibilities in agriculture and industry for classifying and determining physical properties of seeds and other materials.

  17. Does B12 deficiency lead to lack of treatment response to conventional antidepressants?

    Science.gov (United States)

    Kate, Natasha; Grover, Sandeep; Agarwal, Munish

    2010-11-01

    We present two cases of treatment-resistant depression that improved with recognition and correction of the underlying medical etiology of vitamin B12 deficiency. Supplementations of vitamin B12 to the same antidepressant regimen that the patient had not responded earlier led to response. Two male subjects who were vegetarians presented with long-standing histories of depression and had not responded to three adequate trials of antidepressants. Upon investigation, the authors found that the subjects had low vitamin B12 levels. Both cases improved with supplementation of vitamin B12. Subjects with depression who do not respond to conventional antidepressants should be evaluated for nutritional factors.

  18. Prevalence of Vitamin B12 Deficiency Among Pregnant Women in Samsun Province of Turkey

    Directory of Open Access Journals (Sweden)

    Ebru Yilmaz Keskin

    2014-08-01

    Results: Thirty-six (58.1% women had a low serum vitamin B12 level (9.99 and micro;mol/L. All of the 20 infants examined had normal neurodevelopmental findings. Vitamin B12 supplementation resulted in normalization of vitamin B12 and homocysteine levels in all the cases. Conclusion: The frequency of neonatal vitamin B12 deficiency secondary to maternal deficiency may be higher than thought in Samsun province of Turkey. Large-scale screening studies may reveal its prevalence more accurately, and may help in taking preventive measurements. [Cukurova Med J 2014; 39(4.000: 840-847

  19. High Prevalence of Vitamin B12 Deficiency and No Folate Deficiency in Young Children in Nepal.

    Science.gov (United States)

    Ng'eno, Bernadette N; Perrine, Cria G; Whitehead, Ralph D; Subedi, Giri Raj; Mebrahtu, Saba; Dahal, Pradiumna; Jefferds, Maria Elena D

    2017-01-17

    Many children in low- and middle-income countries may have inadequate intake of vitamin B12 and folate; data confirming these inadequacies are limited. We used biochemical, demographic, behavioral and anthropometric data to describe the folate and vitamin B12 concentrations among six- to 23-month-old Nepalese children. Vitamin B12 (serum B12 B12 deficiency. The vitamin B12 geometric mean was 186 pmol/L; 30.2% of children were deficient. The mean RBC folate concentration was 13,612 nmol/L; there was no deficiency. Factors associated with vitamin B12 deficiency included: (a) age six to 11 months (adjusted odds ratio (aOR) 1.51; 95% confidence interval (CI): 1.18, 1.92) or 12-17 months (aOR 1.38; 95% CI: 1.10, 1.72) compared to 18-23 months; (b) being stunted (aOR 1.24; 95% CI: 1.03, 1.50) compared to not being stunted; (c) and not eating animal-source foods (aOR 1.85; 95% CI: 1.42, 2.41) compared to eating animal-source foods the previous day. There was a high prevalence of vitamin B12 deficiency, but no folate deficiency. Improving early feeding practices, including the consumption of rich sources of vitamin B12, such as animal-source foods and fortified foods, may help decrease deficiency.

  20. 血清活性维生素B12检测在维生素B12缺乏中的应用价值%The value of the serum active vitamin B12 in vitamin B12 deficiency

    Institute of Scientific and Technical Information of China (English)

    陈珊瑚; 张文辉; 周碧碧; 陈晓东

    2015-01-01

    目的 探讨血清中活性维生素B12检测在维生素B12缺乏中的应用价值.方法 采用酶免疫发光分析竞争法检测血清中维生素B12和叶酸的含量,及ELISA法检测血清活性维生素B12,通过ROC曲线分析活性维生素B12在诊断维生素B12缺乏中的特异度和敏感度;并且通过回归分析活性维生素B12水平与性别、年龄、总维生素B12及叶酸的相关性;统计分析各疾病组中活性维生素B12含量的累积百分比.结果 血清活性维生素B12判断维生素B12缺乏的ROC曲线下面积为0.983,敏感度为60.0%,特异性为99.2%;活性维生素B12与总维生素B12和叶酸存在良好的正相关,P<0.001,与年龄、性别不相关;各病例组中血液病组的活性维生素B12含量累计百分比最高,其次为神经系统疾病组.结论 血清活性维生素B12是用于临床维生素B12缺乏诊断较敏感、特异的指标,在血液病、神经系统疾病患者中,其临床应用价值更突出.

  1. Vitamin B12 deficiency is associated with cardiovascular autonomic neuropathy in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    Hansen, Christian S; Jensen, Jan S; Ridderstråle, Martin

    2017-01-01

    AIMS: Vitamin B12 deficiency could be associated with cardiovascular autonomic neuropathy (CAN) in diabetes patients. We aim to investigate the association between serum levels of vitamin B12 and CAN in type 2 diabetes patients. METHODS: 469 ambulatory type 2 diabetes patients (mean diabetes.......01; 0.43, p=0.038), and a decrease in 5min RHR of 0.25 beats per minute (95% CI -0.47; -0.03, p=0.025). CONCLUSION: Vitamin B12 may be inversely associated with CAN in patients with type 2 diabetes. Confirmatory studies investigating a causal role of vitamin B12 for the development of diabetic CAN...

  2. Peptide B12: emerging trends at the interface of inorganic chemistry, chemical biology and medicine.

    Science.gov (United States)

    Zelder, Felix; Zhou, Kai; Sonnay, Marjorie

    2013-01-28

    The sophisticated and efficient delivery of vitamin B(12) ("B(12)") into cells offers promise for B(12)-bioconjugates in medicinal diagnosis and therapy. It is therefore surprising that rather little attention is presently paid to an alternative strategy in drug design: the development of structurally perfect, but catalytically inactive semi-artificial B(12) surrogates. Vitamin B(12) cofactors catalyse important biological transformations and are indispensible for humans and most other forms of life. This strong metabolic dependency exhibits enormous medicinal opportunities. Inhibitors of B(12) dependent enzymes are potential suppressors of fast proliferating cancer cells. This perspective article focuses on the design and study of backbone modified B(12) derivatives, particularly on peptide B(12) derivatives. Peptide B(12) is a recently introduced class of biomimetic cobalamins bearing an artificial peptide backbone with adjustable coordination and redox-properties. Pioneering biological studies demonstrated reduced catalytic activity, combined with inhibitory potential that is encouraging for future efforts in turning natural cofactors into new anti-proliferative agents.

  3. Smoking Discriminately Changes the Serum Active and Non-Active Forms of Vitamin B12.

    Science.gov (United States)

    Shekoohi, Niloofar; Javanbakht, Mohammad Hassan; Sohrabi, Marjan; Zarei, Mahnaz; Mohammadi, Hamed; Djalali, Mahmoud

    2017-06-01

    Smoking may modify the appetite, and consequently affect nutrient intake and serum micronutrients. The effect of smoking on vitamin B12 status has been considered in several studies. The research proposed that organic nitrites, nitro oxide, cyanides, and isocyanides of cigarette smoke interfere with vitamin B12 metabolism, and convert it to inactive forms. This research was carried out to determine the serum level of active and inactive forms of vitamin B12 in male smokers in comparison with male nonsmokers. This is a case-control study, in which the participants were 85 male smokers and 85 male nonsmokers. The serum levels of total and active form of vitamin B12 were measured. Dietary intake was recorded by a quantitative food frequency questionnaire and one-day 24-hour dietary recall method. Independent two sample T test was used to compare quantitative variables between the case and control groups. The serum level of total vitamin B12 was not significantly different between two groups, but serum level of active form of vitamin B12 in the smoking group was significantly lower than non-smoking group (Pvitamin B12 in smokers in the Iranian community. The results of this study identified that serum level of total vitamin B12 might be not different between smoking and non-smoking people, but the function of this vitamin is disturbed in the body of smokers through the reduction of serum level of active form of vitamin B12.

  4. Vitamin B 12 Deficiency and Multiple Sclerosis; Is there Any Association?

    Directory of Open Access Journals (Sweden)

    Mohamad Reza Najafi

    2012-01-01

    Full Text Available Background: Vitamin B 12 (Cobalamin deficiency can result in some clinical and paraclinical characteristics similar to what is seen in multiple sclerosis (MS patients. This study aimed to evaluate the controversial association between vitamin B 12 deficiency and MS. Methods: We measured serum vitamin B 12 in 60 patients with MS and 38 healthy controls. Clinical disability was evaluated according to the Extended Disability Status Scale (EDSS. Serum B 12 concentration was measured with Radioimmunoassay Dual Isotope method. The cutoff value for low serum vitamin B 12 concentrations was 75 pg/mL. Patients were in remission at the time of blood draw. Results: There were 13 (21.6% MS patients and 10 (26.3% controls with low serum B 12 concentration with no significant difference between the groups; P>0.05. The mean serum vitamin B 12 concentration in MS patients (108.9±45.3 pg/mL was not significantly different compared with controls (98.9±44.4 pg/mL; P=0.284. Likewise, there was no correlation between the concentration of serum vitamin B 12 and disease′ age of onset, duration, subtypes, or disability status. Conclusions: In contrast to some previous reports, our findings did not support any association between B 12 deficiency and MS.

  5. Monitoring Mechanical Motion of Carbon Nanotube based Nanomotor by Optical Absorption Spectrum

    CERN Document Server

    Wang, Baomin; Wang, Zhan; Wang, Yong; Liu, Kaihui

    2016-01-01

    The optical absorption spectrums of nanomotors made from double-wall carbon nanotubes have been calculated with the time-dependent density functional based tight binding method. When the outer short tube of the nanomotor moves along or rotates around the inner long tube, the peaks in the spectrum will gradually evolve and may shift periodically, the amplitude of which can be as large as hundreds of meV. We show that the features and behaviors of the optical absorption spectrum could be used to monitor the mechanical motions of the double-wall carbon nanotube based nanomotor.

  6. CdTe quantum dot as a fluorescence probe for vitamin B12 in dosage form

    Science.gov (United States)

    Vaishnavi, E.; Renganathan, R.

    2013-11-01

    We here report the CdTe quantum dot (CdTe QDs)-based sensor for probing vitamin B12 derivatives in aqueous solution. In this paper, simple and sensitive fluorescence quenching measurements has been employed. The Stern-Volmer constant (KSV), quenching rate constant (kq) and binding constant (K) were rationalized from fluorescence quenching measurement. Furthermore, the fluorescence resonance energy transfer (FRET) mechanism was discussed. This method was applicable over the concentration ranging from 1 to 14 μg/mL (VB12) with correlation coefficient of 0.993. The limit of detection (LOD) of VB12 was found to be 0.15 μg/mL. Moreover, the present approach opens a simple pathway for developing cost-effective, sensitive and selective QD-based fluorescence sensors/probes for biologically significant VB12 in pharmaceutical sample with mean recoveries in the range of 100-102.1%.

  7. Validity and reproducibility of folate and vitamin B12 intakes estimated from a self-administered diet history questionnaire in Japanese pregnant women

    Directory of Open Access Journals (Sweden)

    Shiraishi Mie

    2012-03-01

    Full Text Available Abstract Background No validated dietary questionnaire for assessing folate and vitamin B12 intakes during pregnancy is available in Japan. We evaluated the validity and reproducibility of intakes of folate and vitamin B12 estimated from a self-administered diet history questionnaire (DHQ in Japanese pregnant women. Methods A sample of 167 healthy subjects with singleton pregnancies in the second trimester was recruited at a private obstetric hospital in metropolitan Tokyo from June to October 2008 (n = 76, and at a university hospital in Tokyo from June 2010 to June 2011 (n = 91. The dietary intakes of folate and vitamin B12 were assessed using the DHQ. The serum concentrations of folate and vitamin B12 were measured as reference values in the validation study. To assess the reproducibility of the results, 58 pregnant women completed the DHQ twice within 4-5 week interval. Results Significantly positive correlations were found between energy-adjusted intakes and serum concentrations of folate and vitamin B12 (r = 0.286, p p = 0.004, respectively. After excluding the participants with nausea (n = 121, the correlation coefficient for vitamin B12 increased to 0.313 (p = 0.001. When participants were classified into quintiles based on intakes and serum concentrations of folate and vitamin B12 , approximately 60% were classified in the same or adjacent quintile. The intraclass correlation coefficients of the two-time DHQ were 0.725 for folate and 0.512 for vitamin B12 . Conclusion The present study indicated that the DHQ had acceptable validity and reproducibility for assessing folate and vitamin B12 intakes in Japanese pregnant women.

  8. The effects of isomaltulose, isomalt, and isomaltulose-based oligomers on mineral absorption and retention.

    Science.gov (United States)

    Kashimura, J; Kimura, M; Itokawa, Y

    1996-09-01

    We carried out a balance study to examine the effects of isomaltulose, lactose, isomalt, and isomaltulose-based oligomers (IBOs) on mineral (calcium, magnesium, phosphorus, and iron) absorption and retention. Four-week-old male Wistar rats were divided into five groups of six rats each and fed a basal diet or diet the containing either 5% isomaltulose, 5% lactose, 5% isomalts or isomaltulose-based oligomers (IBOs) ad libitum for 16 d. After 1 wk, the animals were subjected to a 5-d mineral (calcium, magnesium, phosphorus, and iron) balance study. The isomalt feeding, as well as the IBOs feeding, led to significantly elevated mineral absorption and retention. On the other hand, lactose feeding, widely known to enhance calcium absorption, increased only calcium absorption and isomaltulose feeding did not affect mineral absorption or retention. The organic acids in cecum contents were increased by IBOs or isomalt feeding. Succinic and acetic acids in cecum contents were significantly increased by IBOs feeding. Similarly, succinic, acetic, and i-valeric acids and total amount of organic acid in cecum content were significantly increased by isomalt feeding. Although the organic acids in cecum contents were increased by IBOs or isomalt feeding, the pH values and acidity in cecum contents were not changed by IBOs or isomalt feeding. The effect of addition of various organic acids to the mucosal fluid was examined with in vitro study using a hindgut segment. By the addition of acetic acid, and butyric acid, the mineral (calcium, magnesium, and phosphorus) uptake was increased.

  9. Acupuncture and vitamin B12 injection for Bell’s palsy:no high-quality evidence exists

    Institute of Scientific and Technical Information of China (English)

    Li-li Wang; Ling Guan; Peng-liang Hao; Jin-long Du; Meng-xue Zhang

    2015-01-01

    OBJECTIVE: To assess the efifcacy of acupuncture combined with vitamin B12 acupoint injection versus acupuncture alone to reduce incomplete recovery in patients with Bell’s palsy. DATA RETRIEVAL:A computer-based online retrieval of Medline, Web of Science, CNKI, CBM databases until April 2014 was performed for relevant trials, using the key words “Bell’s palsy or idiopathic facial palsy or facial palsy” and “acupuncture or vitamin B12 or methylcobalamin”. STUDY SELECTION:All randomized controlled trials that compared acupuncture with acupuncture combined with vitamin B12 in patients with Bell’s palsy were included in the me-ta-analysis. The initial treatment lasted for at least 4 weeks. The outcomes of incomplete facial recovery were monitored. The scoring index varied and the deifnition of healing was consistent. The combined effect size was calculated by using relative risk (RR) with 95% conifdence interval (CI) using the ifxed effect model of Review Manager. MAIN OUTCOME MEASURES:Incomplete recovery rates were chosen as the primary outcome. RESULTS: Five studies involving 344 patients were included in the ifnal analysis. Results showed that the incomplete recovery rate of Bell’s palsy patients was 44.50% in the acupuncture combined with vitamin B12 group but 62.57% in the acupuncture alone group. The major acupoints were Taiyang(EX-HN5),Jiache (ST6),Dicang (ST4) andSibai (ST2). The combined effect size showed that acupuncture combined with vitamin B12 was better than acupuncture alone for the treatment of Bell’s palsy (RR = 0.71, 95%CI: 0.58–0.87;P = 0.001), this result held true when 8 patients lost to follow up in one study were included into the analyses (RR = 0.70, 95%CI: 0.58–0.86;P = 0.0005). In the subgroup analyses, the therapeutic effect in patients of the electroacupuncture subgroup was better than in the non-electroacupuncture subgroup (P = 0.024). There was no signiifcant dif-ference in the incomplete recovery rate by subgroup

  10. The vitamin B12 and Se status of lambs during their transition from milk-fed monogastric to grazing herbivore.

    Science.gov (United States)

    Knowles, S O; Grace, N D

    2017-05-01

    To estimate how the lamb's transition from a monogastric at birth to a grazing ruminant at weaning affects its dietary intake of trace nutrients from milk and pasture, and to determine whether its vitamin B12 and Se status changes during that period. We reviewed published reports of field trials in New Zealand where flocks were managed on mixed sward pastures without additional supplements. Information on intakes of milk and pasture was drawn from studies of suckling lambs grazing with ewes for up to 20 weeks. We calculated the quantities of vitamin B12, Co and Se ingested and absorbed by lambs between birth and weaning. Trace nutrient status was based on concentrations of vitamin B12 in serum and Se in blood. Six studies met our inclusion criteria regarding age of lambs, supplementation and sampling frequency. In each, blood had been collected at regular intervals from birth to weaning. Changes over time in concentrations of vitamin B12 and Se were analysed using regression procedures. Estimated Se intake increased from approximately 5 µg/day near birth to 25 µg/day near weaning, but Se absorbed was less variable, being approximately 10 µg/day. Estimated vitamin B12 intake near birth was approximately 8 µg/day and increased to 90 µg/day by weaning, with the amount being absorbed increasing from 0.8 to 9 µg/day. Concentrations of trace elements in unsupplemented lambs among the six studies varied from deficient to adequate. Linear regressions indicated that there was little change in concentrations of vitamin B12 and Se between birth and weaning in four studies (p>0.05), and mean concentrations measured at docking did not differ from those at weaning in four studies where this could be assessed (p>0.1). From newborn to weaned, a lamb's physiology develops from monogastric to ruminant. The change in diet from milk to pasture presents markedly different chemical forms and concentrations of some trace nutrients. Despite this, the vitamin B12 and Se

  11. Vitamin B12 deficiency: an important reversible co-morbidity in neuropsychiatric manifestations.

    Science.gov (United States)

    Issac, Thomas Gregor; Soundarya, Soundararajan; Christopher, Rita; Chandra, Sadanandavalli Retnaswami

    2015-01-01

    Vitamin B12 deficiency is a common condition causing neurologic, cognitive, psychiatric, and mood symptoms. With varied religious, ethnic, and socioeconomic heterogeneity among the people in India greatly influencing their dietary habits and with the high prevalence of Helicobacter pylori infection, Vitamin B12 deficiency is not uncommon, but is often under recognized due to the lack of classical symptomatic presentation. Retrospective study on Vitamin B12 deficiency with neuropsychiatric symptoms in patients who attended neurology, psychiatry, and geriatric OPDs for a period of 1 year in a specialized neuropsychiatric institute in South India. Out of 259 patients who had Vitamin B12 deficiency (B12 levels were vegetarians while 43.3% were nonvegetarians. In our study, Vitamin B12 deficiency was more prevalent in elderly males (56.67%) and was associated with increased severity of behavioral disturbances (P = 0.043) which was the most common presentation. Memory loss was present in 16 (84.2%) patients of severe Vitamin B12 deficiency. Hindi mental status examination (HMSE) score was graded as B12 deficiency was significantly associated with increased serum cholesterol (P = 0.019) and was significantly prevalent in neurological disorders when compared with primary psychiatric illnesses (P = 0.001). Mean folate and mean homocysteine in our study was 11.7 ± 6.44 ng/ml and 17.77 ± 5.45 μmol/L, respectively. Eighty percent of the population had normal folate levels whereas mean homocysteine values were much higher than that of the western population (10-12 μmol/L). Vitamin B12 deficiency though common in India is often overlooked. It increases the load of cognitive decline and accentuates vascular risk factors in neuropsychiatric illnesses. Vitamin B12 deficiency also increases homocysteine levels contributing to the vascular comorbidity in cerebro and cardiovascular illnesses. So prevention, early detection, and management of this reversible Vitamin B12 deficiency

  12. Long-term Metformin Therapy and Monitoring for Vitamin B12 Deficiency Among Older Veterans.

    Science.gov (United States)

    Kancherla, Vijaya; Elliott, John L; Patel, Birju B; Holland, N Wilson; Johnson, Theodore M; Khakharia, Anjali; Phillips, Lawrence S; Oakley, Godfrey P; Vaughan, Camille P

    2017-05-01

    To examine the association between long-term metformin therapy and serum vitamin B12 monitoring. Retrospective cohort study. A single Veterans Affairs Medical Center (VAMC), 2002-2012. Veterans 50 years or older with either type 2 diabetes and long-term metformin therapy (n = 3,687) or without diabetes and no prescription for metformin (n = 13,258). We determined diabetes status from outpatient visits, and defined long-term metformin therapy as a prescription ≥500 mg/d for at least six consecutive months. We estimated the proportion of participants who received a serum B12 test and used multivariable logistic regression, stratified by age, to evaluate the association between metformin use and serum B12 testing. Only 37% of older adults with diabetes receiving metformin were tested for vitamin B12 status after long-term metformin prescription. The mean B12 concentration was significantly lower in the metformin-exposed group (439.2 pg/dL) compared to those without diabetes (522.4 pg/dL) (P = .0015). About 7% of persons with diabetes receiving metformin were vitamin B12 deficient (vitamin B12 testing compared to those without metformin exposure, after adjusting for sex, race and ethnicity, body mass index, and number of years treated at the VAMC. Long-term metformin therapy is significantly associated with lower serum vitamin B12 concentration, yet those at risk are often not monitored for B12 deficiency. Because metformin is first line therapy for type 2 diabetes, clinical decision support should be considered to promote serum B12 monitoring among long-term metformin users for timely identification of the potential need for B12 replacement. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

  13. Hard x-ray photoemission study of Yb1-x Zr x B12: the effects of electron doping on the Kondo insulator YbB12

    Science.gov (United States)

    Rousuli, A.; Sato, H.; Iga, F.; Hayashi, K.; Ishii, K.; Wada, T.; Nagasaki, T.; Mimura, K.; Anzai, H.; Ichiki, K.; Ueda, S.; Kondo, A.; Kindo, K.; Takabatake, T.; Shimada, K.; Namatame, H.; Taniguchi, M.

    2017-07-01

    We have carried out hard x-ray photoemission spectroscopy (HAXPES) of Yb1-x Zr x B12 (0≤slant x≤slant 0.875 ) to study the effects of electron doping on the Kondo insulator YbB12. The Yb valences of Yb1-x Zr x B12 at 300 K estimated from the Yb 3d HAXPES spectra decreased after substituting Yb with Zr from 2.93 for YbB12 to 2.83 for Yb0.125Zr0.875B12. A temperature dependent valence decrease was found upon cooling for all doping concentrations. We found peak shifts of the B 1s and Zr 3d5/2, and Yb3+ 4f spectra toward the deeper binding-energy with increasing Zr concentration, which indicates a shift of the Fermi level to the higher energy and that of the Yb 4f hole level close to the Fermi level, respectively, due to electron doping. These results qualitatively show the enhanced hybridization between the Yb 4f and conduction-band states with Zr substitution, consistent with magnetic susceptibility measurements.

  14. Synchrotron radiation based Mössbauer absorption spectroscopy of various nuclides

    Science.gov (United States)

    Masuda, Ryo; Kobayashi, Yasuhiro; Kitao, Shinji; Kurokuzu, Masayuki; Saito, Makina; Yoda, Yoshitaka; Mitsui, Takaya; Seto, Makoto

    2016-12-01

    Synchrotron-radiation (SR) based Mössbauer absorption spectroscopy of various nuclides is reviewed. The details of the measuring system and analysis method are described. Especially, the following two advantages of the current system are described: the detection of internal conversion electrons and the close distance between the energy standard scatterer and the detector. Both of these advantages yield the enhancement of the counting rate and reduction of the measuring time. Furthermore, SR-based Mössbauer absorption spectroscopy of 40K, 151Eu, and 174Yb is introduced to show the wide applicability of this method. In addition to these three nuclides, SR-based Mössbauer absorption spectroscopy of 61Ni, 73Ge, 119Sn, 125Te, 127I, 149Sm, and 189Os has been performed. We continue to develop the method to increase available nuclides and to increase its ease of use. The complementary relation between the time-domain method using SR, such as nuclear forward scattering and the energy-domain methods such as SR-based Mössbauer absorption spectroscopy is also noted.

  15. Synchrotron radiation based Mössbauer absorption spectroscopy of various nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Ryo, E-mail: masudar@rri.kyoto-u.ac.jp; Kobayashi, Yasuhiro; Kitao, Shinji; Kurokuzu, Masayuki; Saito, Makina [Kyoto University, Research Reactor Institute (Japan); Yoda, Yoshitaka [Japan Synchrotron Radiation Research Institute, Resarch and Utilization Division (Japan); Mitsui, Takaya [Japan Atomic Energy Agency, Condensed Matter Science Division, Sector of Nuclear Science Research (Japan); Seto, Makoto [Kyoto University, Research Reactor Institute (Japan)

    2016-12-15

    Synchrotron-radiation (SR) based Mössbauer absorption spectroscopy of various nuclides is reviewed. The details of the measuring system and analysis method are described. Especially, the following two advantages of the current system are described: the detection of internal conversion electrons and the close distance between the energy standard scatterer and the detector. Both of these advantages yield the enhancement of the counting rate and reduction of the measuring time. Furthermore, SR-based Mössbauer absorption spectroscopy of {sup 40}K, {sup 151}Eu, and {sup 174}Yb is introduced to show the wide applicability of this method. In addition to these three nuclides, SR-based Mössbauer absorption spectroscopy of {sup 61}Ni, {sup 73}Ge, {sup 119}Sn, {sup 125}Te, {sup 127}I, {sup 149}Sm, and {sup 189}Os has been performed. We continue to develop the method to increase available nuclides and to increase its ease of use. The complementary relation between the time-domain method using SR, such as nuclear forward scattering and the energy-domain methods such as SR-based Mössbauer absorption spectroscopy is also noted.

  16. Impact of Vitamin B12 and Nitrate Availability on the Concentration of Particulate Dimethylsulfoniopropionate in Phytoplankton

    Science.gov (United States)

    Zavala, J.; Lee, P. A.; Schanke, N. L.; Pound, H.; Penta, W. B.; Shore, S. K.

    2016-02-01

    The production of particulate dimethylsulfoniopropionate (DMSPp) was examined in natural phytoplankton communities from the South Atlantic Bight near Savannah, Georgia, during an expedition in June 2015. Vitamin B12 and nitrate were added to seawater samples from a coastal and an oceanic site, both of which contained low-biomass, cyanobacteria-dominated communities. Under nitrate-limited conditions, irrespective of changes in B12 levels, DMSPp concentrations increased. DMSPp concentrations of these mixed phytoplankton communities did not appear to be limited by the availability of B12. In a laboratory experiment, DMSPp concentrations in the diatom Phaeodactylum tricornutum were measured after the removal of vitamin B12 and nitrate from a synthetic seawater culture media. DMSPp concentrations increased under nitrate-limited conditions, irrespective of changes in B12 levels, and are argued to be the result of increased biosynthesis. DMSPp concentrations in P. tricornutum were unaffected by B12 limitation. It is hypothesized that P. tricornutum is using the B12-independent methionine synthase MetE to synthesize DMSPp rather than the B12-dependent methionine synthase MetH.

  17. Serum Vitamin B12 and thyroid hormone levels in Saudi patients with multiple sclerosis

    Directory of Open Access Journals (Sweden)

    Fahd A Al-Khamis

    2016-01-01

    Full Text Available Objectives: To determine the relationship between Vitamin B12 levels and thyroid hormones in patients with multiple sclerosis (MS. Materials and Methods: One hundred and ten patients with MS were recruited for this study after Institutional Review Board approval. All patients signed a written informed consent form and donated a single blood sample. Plasma Vitamin B12 levels, triiodothyronine (T3, and thyroxine (T4 hormone levels were measured. Data were analyzed using the Statistical Package for Social Sciences (SPSS software. Results: Analysis of Vitamin B12 levels in 110 patients with MS revealed that 65% had normal levels of Vitamin B12 (200-900 pg/ml, 30% had low levels of Vitamin B12 (<200 pg/ml, and 5% high levels of Vitamin B12 (higher than 900 pg/ml. Further analysis of patients with low levels of Vitamin B12 revealed that this cohort exhibited a significantly high number of patients with low levels of the thyroid hormones triiodothyronine (T3 and thyroxine (T4 (P < 0.005. Conclusion: This study suggests a relationship between Vitamin B12 levels and thyroid hormones. This opens the possibility that the use of therapies that increase triiodothyronine (T3 and thyroxine (T4 levels might be beneficial to patients with MS.

  18. Svaer vitamin B12-mangel hos spaedbørn brysternaeret af veganere

    DEFF Research Database (Denmark)

    Roed, Casper; Skovby, Flemming; Lund, Allan Meldgaard

    2009-01-01

    with cyanocobalamin was instituted with remission of symptoms. Since infants risk irreversible neurologic damage following severe vitamin B12 deficiency, early diagnosis and treatment are mandatory. Vegan and vegetarian women should take vitamin B12 supplementation during the pregnancy and nursing period...

  19. Folate and vitamin B12-related biomarkers in relation to brain volumes

    NARCIS (Netherlands)

    van der Zwaluw, Nikita L.; Brouwer-Brolsma, Elske M.; van de Rest, Ondine; van Wijngaarden, Janneke P.; In ’t Veld, Paulette H.; Kourie, Daniella I.; Swart, Karin M A; Enneman, Anke W.; van Dijk, Suzanne C.; van der Velde, Nathalie; Kessels, Roy P C; Smeets, Paul A M; Kok, Frans J.; Dhonukshe-Rutten, Rosalie A M; de Groot, Lisette C P G M

    2017-01-01

    Aim: We investigated cross-sectional associations between circulating homocysteine, folate, biomarkers of vitamin B12 status and brain volumes. We furthermore compared brain volumes of articipants who received daily folic acid and vitamin B12 supplementation with participants who did not. Methods:

  20. Masking of vitamin B12 deficiency associated neuropathy by folic acid

    NARCIS (Netherlands)

    Amsterdam JGC van; Opperhuizen A; Jansen EHJM; TOX

    2005-01-01

    The Dutch authorities consider fortifying certain foods with folic acid. Folic acid supplementation may, however, mask vitamin B12 deficiency and increase the incidence of peripheral neuropathy. This literature review outlines published studies to the potential masking of vitamin B12 deficiency rel

  1. 17 CFR 240.12b-12 - Requirements as to paper, printing and language.

    Science.gov (United States)

    2010-04-01

    ..., printing and language. 240.12b-12 Section 240.12b-12 Commodity and Securities Exchanges SECURITIES AND... paper, printing and language. (a) Statements and reports shall be filed on good quality, unglazed white... as to be clearly distinguishable as such on photocopies. (c) The body of all printed statements...

  2. 17 CFR 270.8b-12 - Requirements as to paper, printing and language.

    Science.gov (United States)

    2010-04-01

    ..., printing and language. 270.8b-12 Section 270.8b-12 Commodity and Securities Exchanges SECURITIES AND... Requirements as to paper, printing and language. (a) Registration statements and reports shall be filed on good.... (d) The body of all printed registration statements and reports and all notes to financial...

  3. Vitamin B-12 and homocysteine status among vegetarians: a global perspective.

    Science.gov (United States)

    Elmadfa, Ibrahim; Singer, Ingrid

    2009-05-01

    Evidence exists that well-planned vegetarian diets provide numerous health benefits and are appropriate for all stages of the life cycle. It is also known that animal foods provide micronutrients that are nonexistent or available only in limited amounts in plant foods. Restriction or exclusion of all animal foods may therefore result in low intake of certain micronutrients such as vitamin B-12, thereby affecting vitamin B-12 status and elevating plasma homocysteine concentrations. Overall, the studies we reviewed showed reduced mean vitamin B-12 status and elevated mean homocysteine concentrations in vegetarians, particularly among vegans. Low vitamin B-12 intake may lead to decreased bioavailability and functional deficiency of cobalamin. Although early noticeable symptoms of vitamin B-12 deficiency are nonspecific (unusual fatigue, digestion problems, frequent upper respiratory infections), the best-known clinical manifestations of cobalamin malabsorption are hematologic (pernicious anemia) and neurologic symptoms. Hyperhomocysteinemia is associated with an increased risk of atherosclerosis and cardiovascular disease. Given these health concerns, vegetarians, particularly vegans, must be advised to carefully plan their diets, to monitor their plasma vitamin B-12 on a regular basis to facilitate early detection of low cobalamin status, and to use vitamin B-12-fortified foods or take vitamin B-12 supplements if necessary.

  4. Folate and vitamin B12 status in Latin America and the Caribbean: An update

    Science.gov (United States)

    Background: The current magnitude of folate and vitamin B12 deficiency in Latin America and the Caribbean is uncertain. Objective: To summarize data on plasma or serum vitamin B12 and folate concentrations in Latin America and the Caribbean reported since 1990, a period that covers the era before an...

  5. Relationship between vitamin B12 and sensory and motor peripheral nerve function in older adults.

    NARCIS (Netherlands)

    Leishear, K.; Boudreau, R.M.; Studenski, S.A.; Ferrucci, L.; Rosano, C.; Rekeneire, N. de; Houston, D.K.; Kritchevsky, S.B.; Schwartz, A.V.; Vinik, A.I.; Hogervorst, E.; Yaffe, K.; Harris, T.B.; Newman, A.B.; Strotmeyer, E.S.

    2012-01-01

    OBJECTIVES: To examine whether deficient B12 status or low serum B12 levels are associated with worse sensory and motor peripheral nerve function in older adults. DESIGN: Cross-sectional. SETTING: Health, Aging and Body Composition Study. PARTICIPANTS: Two thousand two hundred and eighty-seven adult

  6. De diagnostiek van vitamine-B12-deficiëntie herzien

    NARCIS (Netherlands)

    Wiersinga, W J; de Rooij, S E J A; Huijmans, J G M; Fischer, C; Hoekstra, Joost B. L.

    2005-01-01

    Vitamin B12 (cobalamin) deficiency is a common disorder with potential irreversible haematological and neurological consequences. Currently used diagnostic tests such as the evaluation of serum vitamin B12 and the Schilling test are insufficient, e.g. the positive predictive value of a low serum vit

  7. Research Intensity Synthesis of Propionic Acid and Vitamin B12 Propionibacteria

    Directory of Open Access Journals (Sweden)

    Kuznetsova Tatyana

    2015-10-01

    Full Text Available Conducted the selection and breeding of strains of Propionibacterium shermanii ability to synthesize vitamin B12 and propionic acid. Dedicated 9 propionibacteria strains synthesize vitamin B12 (180-1200 mcgr/ml and propionic acid (0,63- 2,53 g/l.

  8. False-normal vitamin B12 results in a patient with pernicious anaemia.

    Science.gov (United States)

    Wainwright, P; Narayanan, S; Cook, P

    2015-12-01

    Pernicious anaemia is a common autoimmune disorder with a prevalence of approximately 4% amongst Europeans. If untreated, it can result in permanent neurological disability or death. Central to the diagnosis is establishing the presence of vitamin B12 deficiency. Concern has been raised recently regarding false-normal results obtained with competitive-binding vitamin B12 assays performed on automated biochemistry platforms in patients with pernicious anaemia due to the presence of interfering anti-intrinsic factor antibodies in the patient sample. We report a case in which diagnosis of pernicious anaemia was delayed due to false-normal vitamin B12 results. Questioning the results in light of high pre-test probability, and knowledge of the role of functional markers of vitamin B12 deficiency enabled the correct diagnosis to be made so that effective treatment could be initiated. It is crucial that those who frequently request vitamin B12 are aware of the potential problems with the available assays and how these problems can be addressed. We suggest that all patients with normal vitamin B12 levels where there is a high clinical suspicion for deficiency such as a macrocytic anaemia, neurological symptoms or megaloblastic bone marrow should have a functional assay of vitamin B12 (plasma homocysteine or methylmalonic acid) checked to further investigate for vitamin B12 deficiency.

  9. Competitive chemiluminescent enzyme immunoassay for vitamin B12 analysis in human milk

    Science.gov (United States)

    BACKGROUND Few accurate data exist on the concentration of vitamin B12 in human milk. Binding of the vitamin to haptocorrin (HC) can interfere with the assay if not removed by pretreatment, and very low values can occur in women with poor B12 status. This study evaluated two competitive enzyme bind...

  10. Interventions with vitamins B6, B12 and C in pregnancy

    Science.gov (United States)

    The water-soluble vitamins B6, B12 and C play important roles in maternal health as well as fetal development and physiology during gestation. This systematic review evaluates the risks and benefits of interventions with vitamins B6, B12 and C during pregnancy on maternal, neonatal and child health ...

  11. Effect of amino acid availability on vitamin B12 production in Lactobacillus reuteri

    NARCIS (Netherlands)

    Santos, dos F.; Teusink, B.; Molenaar, D.; Heck, van M.; Wels, M.W.W.; Sieuwerts, S.; Vos, de W.M.; Hugenholtz, J.

    2009-01-01

    Recent functional genomics and genome-scale modeling approaches indicated that B12 production in Lactobacillus reuteri could be improved by medium optimization. Here we show that a series of systematic single amino acid omissions could significantly modulate the production of B12 from nearly undetec

  12. Investigation fo Helicobacter Pylori prevalance in children with vitamine B12 deficiency

    Directory of Open Access Journals (Sweden)

    ishak abdurrahman isik

    2015-12-01

    Conclusion: Although vitamin B 12 levels of HP positive patients were lower than that of HP negative patients this differance was not statistically significant. Hereafter new studies with high number of patients will be helpful to investigate relation between HP infection and vitamin B 12 deficiency. [J Contemp Med 2015; 5(4.000: 221-225

  13. Masking of vitamin B12 deficiency associated neuropathy by folic acid

    NARCIS (Netherlands)

    Amsterdam JGC van; Opperhuizen A; Jansen EHJM; TOX

    2005-01-01

    The Dutch authorities consider fortifying certain foods with folic acid. Folic acid supplementation may, however, mask vitamin B12 deficiency and increase the incidence of peripheral neuropathy. This literature review outlines published studies to the potential masking of vitamin B12 deficiency

  14. Vitamin B12 Levels in Rat Organs - No Change Following Prolonged Treatment with Metformin

    DEFF Research Database (Denmark)

    Thagaard, Mikkel Svankjær; Nexø, Ebba; Greibe, Eva

    2015-01-01

    Aim: Few studies have explored vitamin B12 (B12) distribution in control rats and in rats treated with metformin, an anti-diabetic drug known to decrease the plasma level of B12 in humans. Here we report B12 levels in both control rats and in rats treated by two different methods of delivering...... metformin. Methods: Male Wistar rats aged 16 weeks at sacrifice was treated for 6 weeks with daily subcutaneous injections of either saline (n = 10) or metformin (n = 10). We collected plasma and organs for analyses of B12, and we explored the fraction of protein-bound B12 in selected organs. In addition we...... examined the effect of four weeks administration of metformin (n = 10= or sline (n = 10) by intra-peritoneal osmotic pumps on levels of B12 in plasma, liver, and kidneys of rats aged 14 weeks at sacrifice. Results: Median concentration of B12 in the 16 weeks old control rats was highest in the kidney (1350...

  15. The predictive value of vitamin B12 concentrations and hyperhomocysteinaemia for cardiovascular disease.

    NARCIS (Netherlands)

    Oijen, M.G.H. van; Laheij, R.J.F.; Jansen, J.B.M.J.; Verheugt, F.W.A.

    2007-01-01

    BACKGROUND: Cardiovascular disease has been associated with both homocysteine and vitamin B12 levels. However, little information is available about the mutual relation in cardiovascular patients. The aim of this study was to assess the prevalence of vitamin B12 deficiency in patients with

  16. Atopy, asthma, and lung function in relation to folate and vitamin B(12) in adults

    DEFF Research Database (Denmark)

    Thuesen, B H; Husemoen, L L N; Ovesen, L

    2010-01-01

    Recent studies suggested low serum folate and impaired folate metabolism as potential risk factors for development of asthma and atopic disease, but the results are inconsistent. The aim of this study was to investigate the relations of markers of folate and vitamin B12 (B12) deficiency...

  17. Vitamin B12 in Obese Adolescents with Clinical Features of Insulin Resistance

    Directory of Open Access Journals (Sweden)

    Mandy Ho

    2014-12-01

    Full Text Available Emerging evidence indicates an association between obesity, metformin use and reduced vitamin B12 status, which can have serious hematologic, neurologic and psychiatric consequences. This study aimed to examine B12 status in obese adolescents with pre-diabetes and/or clinical features of insulin resistance. Serum B12 was measured using chemiluminescence immunoassay in 103 (43 male, 60 female obese (mean body mass index (BMI z-score ± SD (2.36 ± 0.29, adolescents aged 10 to 17 years, median (range insulin sensitivity index of 1.27 (0.27 to 3.38 and 13.6% had pre-diabetes. Low B12 (<148 pmol/L was identified in eight (7.8% and borderline status (148 to 221 pmol/L in an additional 25 (24.3% adolescents. Adolescents with borderline B12 concentrations had higher BMI z-scores compared to those with normal concentrations (2.50 ± 0.22 vs. 2.32 ± 0.30, p = 0.008 or those with low B12 concentration (2.50 ± 0.22 vs. 2.27 ± 0.226, p = 0.041. In conclusion, nearly a third of obese adolescents with clinical insulin resistance had a low or borderline serum B12 status. Therefore, further investigations are warranted to explore the cause and the impact of low B12 status in obese pediatric populations.

  18. The predictive value of vitamin B12 concentrations and hyperhomocysteinaemia for cardiovascular disease.

    NARCIS (Netherlands)

    Oijen, M.G.H. van; Laheij, R.J.F.; Jansen, J.B.M.J.; Verheugt, F.W.A.

    2007-01-01

    BACKGROUND: Cardiovascular disease has been associated with both homocysteine and vitamin B12 levels. However, little information is available about the mutual relation in cardiovascular patients. The aim of this study was to assess the prevalence of vitamin B12 deficiency in patients with cardiovas

  19. Laser-induced absorption and fluorescence studies of photochromic Schiff bases

    DEFF Research Database (Denmark)

    Kownacki, K.; Mordzinski, A.; Wilbrandt, R.

    1994-01-01

    Three photochromic Schiff bases: N-salicylideneaniline (SA), N-salicylidene-1-naphthylamine (SN), and N,N-bis-(salicylidene)-p-phenylenediamine (Bsp), were studied in acetonitrile by means of steady-state and time-resolved absorption and fluorescence spectroscopy, as well as semiempirical quantum...... chemical calculations. In all these molecules, the transient absorption and two-step laser-induced fluorescence spectra of long-lived transients are remarkably similar. The photochromic species is tentatively assigned to the non-hydrogen bonded form of the proton transfer reaction product...

  20. Targeting the cubilin receptor through the vitamin B(12) uptake pathway: cytotoxicity and mechanistic insight through fluorescent Re(I) delivery.

    Science.gov (United States)

    Viola-Villegas, Nerissa; Rabideau, Amy E; Bartholomä, Mark; Zubieta, Jon; Doyle, Robert P

    2009-08-27

    The intrinsic factor (IF) vitamin B(12) ileum anchored receptor, cubilin, mediates endocytotic uptake of the IF complex of vitamin B(12) to the blood serum. This receptor was targeted for the selective delivery and accumulation of a new bioprobe, a B(12) conjugate of rhenium 2, in the cubilin expressing placental choriocarcinoma BeWo cell line. Competitive uptake and cytotoxicity assays of 2 were investigated and interactions with nuclear DNA explored. In addition, the mechanism of internalization of 2 was confirmed to proceed in an IF-cubilin mediated fashion via siRNA transfection experiments. These studies show the great potential of cubilin as a new target for the delivery of B(12) based conjugates for cancer diagnostics and/or treatment.

  1. Association studies of genetic scores of serum vitamin B12 and folate levels with symptoms of depression and anxiety in two danish population studies

    DEFF Research Database (Denmark)

    Møllehave, L T; Skaaby, T; Simonsen, K S

    2017-01-01

    BACKGROUND/OBJECTIVES: Observational studies have suggested low serum levels of vitamin B12 or folate to be risk factors of depression and anxiety. However, these results may be biased by confounding and reverse causation. Mendelian randomization studies are not subject to these limitations....... The aim was to examine the association of genetic scores of vitamin B12 and folate-associated alleles with depression and anxiety. SUBJECTS/METHODS: The study included 4126 participants from two Danish population-based studies. Serum vitamin B12 and folate were measured. Weighed allele scores were...... calculated as the sum of weights (genetic effect sizes) for 12 and two variants increasing circulating levels of vitamin B12 and folate, respectively. Symptoms of depression and anxiety were assessed by the Symptom Check List (SCL)-90-R, and self-reported doctor-diagnosed depression and anxiety. RESULTS...

  2. A new photoacoustic method based on the modulation of the light induced absorption coefficient

    Science.gov (United States)

    Engel, S.; Wenisch, C.; Müller, F. A.; Gräf, S.

    2016-04-01

    The present study reports on a new photoacoustic (PA) measurement method that is suitable for the investigation of light induced absorption effects including e.g. excited state absorption. Contrary to the modulation of the radiation intensity used in conventional PA-methods, the key principle of this novel setup is based on the modulation of the induced absorption coefficient by light. For this purpose, a pump-probe setup with a pulsed pump laser beam and a continuous probe laser beam is utilized. In this regime, the potential influence of heat on the PA-signal is much smaller when compared to arrangements with pulsed probe beam and continuous pump beam. Beyond that, the negative effect of thermal lenses can be neglected. Thus, the measurement technique is well-suited for materials exhibiting a strong absorption at the pump wavelength. The quantitative analysis of the induced absorption coefficient was achieved by the calibration of the additional PA-signal caused by the continuous probe laser to the PA-signal resulting from the pulsed pump laser using thallium bromoiodide (KRS-5) as sample material.

  3. Effective light absorption and its enhancement factor for silicon nanowire-based solar cell.

    Science.gov (United States)

    Duan, Zhiqiang; Li, Meicheng; Mwenya, Trevor; Fu, Pengfei; Li, Yingfeng; Song, Dandan

    2016-01-01

    Although nanowire (NW) antireflection coating can enhance light trapping capability, which is generally used in crystal silicon (CS) based solar cells, whether it can improve light absorption in the CS body depends on the NW geometrical shape and their geometrical parameters. In order to conveniently compare with the bare silicon, two enhancement factors E(T) and E(A) are defined and introduced to quantitatively evaluate the efficient light trapping capability of NW antireflective layer and the effective light absorption capability of CS body. Five different shapes (cylindrical, truncated conical, convex conical, conical, and concave conical) of silicon NW arrays arranged in a square are studied, and the theoretical results indicate that excellent light trapping does not mean more light can be absorbed in the CS body. The convex conical NW has the best light trapping, but the concave conical NW has the best effective light absorption. Furthermore, if the cross section of silicon NW is changed into a square, both light trapping and effective light absorption are enhanced, and the Eiffel Tower shaped NW arrays have optimal effective light absorption.

  4. Biopharmaceutical modeling of drug supersaturation during lipid-based formulation digestion considering an absorption sink.

    Science.gov (United States)

    Stillhart, Cordula; Imanidis, Georgios; Griffin, Brendan T; Kuentz, Martin

    2014-12-01

    In vitro lipolysis is widely utilized for predicting in vivo performance of oral lipid-based formulations (LBFs). However, evaluation of LBFs in the absence of an absorption sink may have limited in vivo relevance. This study aimed at employing biopharmaceutical modeling to simulate LBF digestion and drug supersaturation in a continuous absorptive environment. Three fenofibrate-loaded LBFs were characterized in vitro (dispersion and lipolysis) and drug precipitation was monitored using in-line Raman spectroscopy. In vitro data were combined with pharmacokinetic data derived from an in vivo study in pigs to simulate intestinal LBF transit. This biopharmaceutical model allowed calculation of lipolysis-triggered drug supersaturation while drug and lipolysis products are absorbed from the intestine. The biopharmaceutical model predicted that, in a continuous absorption environment, fenofibrate supersaturation was considerably lower compared to in vitro lipolysis (non-sink). Hence, the extensive drug precipitation observed in vitro was predicted to be unlikely in vivo. The absorption of lipolysis products increased drug supersaturation, but drug precipitation was unlikely for highly permeable drugs. Biopharmaceutical modeling is a valuable approach for predicting LBFs performance in vivo. In the absence of in vitro tools simulating absorptive conditions, modeling strategies should be further considered.

  5. Dual-gated tunable absorption in graphene-based hyperbolic metamaterial

    Directory of Open Access Journals (Sweden)

    Renxia Ning

    2015-06-01

    Full Text Available The use of a dual-gated tunable absorber in graphene-based hyperbolic metamaterial (GHMM in the near-infrared frequency range was investigated. The horizontal and vertical parts for relative permittivity of GHMM, which consists of monolayer graphene and conventional dielectric, were tuned using the chemical potential. To obtain a large absorption, GHMM was placed on top of a stacked structure containing dielectric and graphene layers and a copper reflector was placed at the bottom. The dual-gated absorber had multiband absorption, which was tuned using the chemical potential of graphene and GHMM. This study focuses on the variation of the absorption with change in the chemical potential and dielectric thickness. The results show that multiband absorption could be attained when chemical potential and dielectric thickness was changed. Broadband absorption could be generated when the frequency ranged from 215 THz to 250 THz. This phenomenon may be valuable for a variety of important applications including optical communication technology and near-infrared stealth communication.

  6. A new in vitro lipid digestion - in vivo absorption model to evaluate the mechanisms of drug absorption from lipid-based formulations.

    Science.gov (United States)

    Crum, Matthew F; Trevaskis, Natalie L; Williams, Hywel D; Pouton, Colin W; Porter, Christopher J H

    2016-04-01

    In vitro lipid digestion models are commonly used to screen lipid-based formulations (LBF), but in vitro-in vivo correlations are in some cases unsuccessful. Here we enhance the scope of the lipid digestion test by incorporating an absorption 'sink' into the experimental model. An in vitro model of lipid digestion was coupled directly to a single pass in situ intestinal perfusion experiment in an anaesthetised rat. The model allowed simultaneous real-time analysis of the digestion and absorption of LBFs of fenofibrate and was employed to evaluate the influence of formulation digestion, supersaturation and precipitation on drug absorption. Formulations containing higher quantities of co-solvent and surfactant resulted in higher supersaturation and more rapid drug precipitation in vitro when compared to those containing higher quantities of lipid. In contrast, when the same formulations were examined using the coupled in vitro lipid digestion - in vivo absorption model, drug flux into the mesenteric vein was similar regardless of in vitro formulation performance. For some drugs, simple in vitro lipid digestion models may underestimate the potential for absorption from LBFs. Consistent with recent in vivo studies, drug absorption for rapidly absorbed drugs such as fenofibrate may occur even when drug precipitation is apparent during in vitro digestion.

  7. Note: A flexible light emitting diode-based broadband transient-absorption spectrometer

    Science.gov (United States)

    Gottlieb, Sean M.; Corley, Scott C.; Madsen, Dorte; Larsen, Delmar S.

    2012-05-01

    This Note presents a simple and flexible ns-to-ms transient absorption spectrometer based on pulsed light emitting diode (LED) technology that can be incorporated into existing ultrafast transient absorption spectrometers or operate as a stand-alone instrument with fixed-wavelength laser sources. The LED probe pulses from this instrument exhibit excellent stability (˜0.5%) and are capable of producing high signal-to-noise long-time (>100 ns) transient absorption signals either in a broadband multiplexed (spanning 250 nm) or in tunable narrowband (20 ns) operation. The utility of the instrument is demonstrated by measuring the photoinduced ns-to-ms photodynamics of the red/green absorbing fourth GMP phosphodiesterase/adenylyl cyclase/FhlA domain of the NpR6012 locus of the nitrogen-fixing cyanobacterium Nostoc punctiforme.

  8. [Measurement of nonuniform temperature and concentration distribution by absorption spectroscopy based on least-square fitting].

    Science.gov (United States)

    Song, Jun-Ling; Hong, Yan-Ji; Wang, Guang-Yu; Pan, Hu

    2013-08-01

    The measurement of nonuniform temperature and concentration distributions was investigated based on tunable diode laser absorption spectroscopy technology. Through direct scanning multiple absorption lines of H2O, two zones for temperature and concentration distribution were achieved by solving nonlinear equations by least-square fitting from numerical and experimental studies. The numerical results show that the calculated temperature and concentration have relative errors of 8.3% and 7.6% compared to the model, respectively. The calculating accuracy can be improved by increasing the number of absorption lines and reduction in unknown numbers. Compared with the thermocouple readings, the high and low temperatures have relative errors of 13.8% and 3.5% respectively. The numerical results are in agreement with the experimental results.

  9. Retardation of myelination due to dietary vitamin B12 deficiency: cranial MRI findings.

    Science.gov (United States)

    Lövblad, K; Ramelli, G; Remonda, L; Nirkko, A C; Ozdoba, C; Schroth, G

    1997-02-01

    Vitamin B12 deficiency is known to be associated with signs of demyelination, usually in the spinal cord. Lack of vitamin B12 in the maternal diet during pregnancy has been shown to cause severe retardation of myelination in the nervous system. We report the case of a 14(1)/2-month-old child of strictly vegetarian parents who presented with severe psychomotor retardation. This severely hypotonic child had anemia due to insufficient maternal intake of vitamin B12 with associated megaloblastic anemia. MRI of the brain revealed severe brain atrophy with signs of retarded myelination, the frontal and temporal lobes being most severely affected. It was concluded that this myelination retardation was due to insufficient intake of vitamin B12 and vitamin B12 therapy was instituted. The patient responded well with improvement of clinical and imaging abnormalities. We stress the importance of MRI in the diagnosis and follow-up of patients with suspected diseases of myelination.

  10. 60岁后要补维生素B12

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    据统计,美国60岁以上的老年人当中,1/5缺乏维生素B12。因此,医学家建议:素食者和老年人尤其要注意多吃富含维生素B12的食物,以弥补膳食中维生素B12不足的缺陷。维生素B12对于维持缝康的神经经胞和红细胞非常关键。缺乏维生素B12轻则导致疲劳、眩晕.重则会引起神经损伤、贫血和痴呆。

  11. Urinary levels of early kidney injury molecules in children with vitamin B12 deficiency.

    Science.gov (United States)

    Güneş, Ali; Aktar, Fesih; Tan, İlhan; Söker, Murat; Uluca, Ünal; Balık, Hasan; Mete, Nuriye

    2016-10-01

    The aim of this study was to investigate urine early kidney injury molecules, including human kidney injury molecule-1 (KIM-1), liver-type fatty-acid binding protein (L-FABP), N-acetyl-b-D-glucosaminidase A (NAG), and neutrophil gelatinase-associated lipocalin (NGAL) in children with vitamin B12 (cobalamin) deficiency (CD). Twelve children with vitamin B12 deficiency and 20 healthy matched controls were included. Hematologic parameters, serum urea, creatinine (Cr), electrolytes, B12 and folate levels were recorded. Estimated glomerular filtration rate (eGFR) was calculated. Urine protein, electrolytes, andurinary early markers were measured. Patients with CD had significantly higher urine electrolyte/Cr ratios (p B12 and urinary markers in the patients (p B12 deficiency suggest a possible subclinical renal dysfunction, which cannot be determined by conventional kidney function tests.

  12. Acute bilateral useless hand syndrome: a rare presenting manifestation of vitamin B12 deficiency.

    Science.gov (United States)

    Biyani, Sumant; Jha, Sneh Kumar; Pandey, Suchit; Shukla, Rakesh

    2015-10-16

    We report a case of bilateral useless hand syndrome, a rare presenting manifestation of vitamin B12 deficiency. A 38-year-old man, a strict vegetarian and a teacher by occupation, presented with acute onset clumsiness of both hands while performing fine movements. Detailed history-taking, examination of the patient and relevant investigations (complete blood count, serum vitamin B12 and MRI of the cervical spinal cord) were carried out. Laboratory analysis was suggestive of vitamin B12 deficiency and MRI demonstrated a lesion involving the posterior columns of the cervical cord. The patient was diagnosed as a case of non-compressive cervical myelopathy predominantly involving the posterior column due to vitamin B12 deficiency. Acute bilateral useless hand syndrome can be a rare presenting feature of vitamin B12 deficiency.

  13. Association of B12 deficiency and clinical neuropathy with metformin use in type 2 diabetes patients.

    Science.gov (United States)

    Singh, A K; Kumar, A; Karmakar, D; Jha, R K

    2013-01-01

    Long-term metformin use has been hypothesized to cause B12 deficiency and neuropathy in Type 2 diabetes patients. However, there is a paucity of Indian data regarding the same. To compare the prevalence of B12 deficiency and peripheral neuropathy in patients with Type 2 diabetes mellitus treated with or without metformin. We recruited patients with Type 2 diabetes and divided them into metformin exposed and nonmetformin exposed groups. We measured baseline demographic variables like age, sex, vegetarian status, and HbA1c levels in both groups. We compared vitamin B12 levels and severity of peripheral neuropathy (using Toronto Clinical Scoring System (TCSS)) in both groups. Definite B12 deficiency was defined as B12 diabetes patients.

  14. Study on methane fermentation and production of vitamin B12 from alcohol waste slurry.

    Science.gov (United States)

    Zhang, Zhenya; Quan, Taisheng; Li, Pomin; Zhang, Yansheng; Sugiura, Norio; Maekawa, Takaaki

    2004-01-01

    We studied biogas fermentation from alcohol waste fluid to evaluate the anaerobic digestion process and the production of vitamin B12 as a byproduct. Anaerobic digestion using acclimated methanogens was performed using the continuously stirred tank reactor (CSTR) and fixed-bed reactor packed with rock wool as carrier material at 55 degrees C. We also studied the effects of metal ions added to the culture broth on methane and vitamin B12 formation. Vitamin B12 production was 2.92 mg/L in the broth of the fixed-bed reactor, twice that of the CSTR. The optimum concentrations of trace metal ions added to the culture liquid for methane and vitamin B12 production were 1.0 and 8 mL/L for the CSTR and fixed-bed reactor, respectively. Furthermore, an effective method for extracting and purifying vitamin B12 from digested fluid was developed.

  15. Serum levels of folic acid and vitamin B12 in Korean patients with vitiligo.

    Science.gov (United States)

    Kim, S M; Kim, Y K; Hann, S K

    1999-06-01

    The association of vitiligo and pernicious anemia has been previously documented. The low levels of folic acid and vitamin B12 were thought to be related to vitiligo. To date, there have been very few reports about the serum levels of folic acid and vitamin B12 in patients with vitiligo. Using radioimmunoassay, we measured the serum levels of folic acid and vitamin B12 in 100 Korean patients with vitiligo. The mean serum levels of folic acid and vitamin B12 were 6.31 +/- 2.82 ng/ml and 630.25 +/- 230.94 pg/ml, respectively, in patients with vitiligo. These levels showed no significant difference compared to the normal control group, suggesting that folic acid and vitamin B12 do not appear to play a role in the pathogenesis of vitiligo.

  16. Serum vitamin B12 levels in young vegans who eat brown rice.

    Science.gov (United States)

    Suzuki, H

    1995-12-01

    A nutritional analysis was conducted on the dietary intake of a group of 6 vegan children aged 7 to 14 who had been living on a vegan diet including brown rice for from 4 to 10 years, and on that of an age-matched control group. In addition, their serum vitamin B12 levels and other data (red blood cell count, hematocrit, hemoglobin, etc.) were determined in the laboratory. In vegans' diets, 2-4 g of nori (dried laver), which contained B12, were consumed daily. Not a single case of symptoms due to B12 deficiency was found. There were no statistically significant differences between the two groups with respect to any of the examination data, including B12 levels (p vegans from suffering B12 deficiency.

  17. Delayed auditory conduction in diabetes: is metformin-induced vitamin B12 deficiency responsible?

    Science.gov (United States)

    Khattar, Deepti; Khaliq, Farah; Vaney, Neelam; Madhu, Sri Venkata

    2016-01-01

    Summary The present study aims to evaluate the functional integrity of the auditory pathway in patients with diabetes taking metformin. A further aim is to assess its association with vitamin B12 deficiency induced by metformin. Thirty diabetics taking metformin and 30 age-matched non-diabetic controls were enrolled. Stimulus-related potentials and vitamin B12 levels were evaluated in all the subjects. The diabetics showed deficient vitamin B12 levels and delayed wave III latency and III–V interpeak latency in the right ear and delayed Na and Pa wave latencies in the left ear compared with the controls. The dose and duration of metformin showed no association with the stimulus-related potentials. Therefore, although vitamin B12 levels were deficient and auditory conduction impairment was present in the diabetics on metformin, this impairment cannot be attributed to the vitamin B12 deficiency. PMID:27358222

  18. Stability of added and in situ-produced vitamin B12 in breadmaking.

    Science.gov (United States)

    Edelmann, Minnamari; Chamlagain, Bhawani; Santin, Marco; Kariluoto, Susanna; Piironen, Vieno

    2016-08-01

    Vitamin B12 exists naturally in foods of animal origin and is synthesised only by certain bacteria. New food sources are needed to ensure vitamin B12 intake in risk groups. This study aimed to investigate the stability of added cyanocobalamin (CNCbl, chemically modified form) and hydroxocobalamin (OHCbl, natural form) and in situ-synthesised vitamin B12 in breadmaking. Samples were analysed both with a microbiological (MBA) and a liquid chromatographic (UHPLC) method to test applicability of these two methods. Proofing did not affect CNCbl and OHCbl levels. By contrast, 21% and 31% of OHCbl was lost in oven-baking steps in straight- and sponge-dough processes, respectively, whereas CNCbl remained almost stable. In sourdough baking, 23% of CNCbl and 44% of OHCbl were lost. In situ-produced vitamin B12 was almost as stable as added CNCbl and more stable than OHCbl. The UHPLC method showed its superiority to the MBA in determining the active vitamin B12.

  19. Reposição de vitamina B12 reduz comportamento depressivo induzido em ratos jovens = Vitamin B12 replacement therapy reduces induced depressive behavior in young rats

    Directory of Open Access Journals (Sweden)

    Brito, Adriana Maria de Oliveira

    2016-01-01

    Conclusões: A depleção suave de vitamina B12 na dieta, em nível não indutor de anemia, favoreceu o estado depressivo em ratos jovens, enquanto a sua suplementação na situação de depleção reverteu esse quadro. Em condições de nutrição adequada, entretanto, a suplementação dessa vitamina não exerceu efeito sobre o estado depressivo. Estes resultados estimulam a realização de mais estudos que aprofundem a avaliação das relações entre vitamina B12 e depressão em jovens. Além disso, este estudo também abre perspectivas para um novo modelo experimental de depressão, induzida por depleção de vitamina B12

  20. Reference Interval and Status for Serum Folate and Serum Vitamin B12 in a Norwegian Population.

    Science.gov (United States)

    Schwettmann, Lutz; Berbu, Siw

    2015-01-01

    Deficiencies of folate and vitamin B12 lead to an elevated serum concentration of homocysteine which has been associated with many diseases including cardiovascular disease. Laboratory algorithms often include initial testing of serum folate and vitamin B12. Reference intervals for these vitamins can vary significantly among populations for which dietary intakes may be different. The aim of this study was to establish reference intervals in a Norwegian population and to assess the folate and vitamin B12 status related to reference intervals. Blood samples were taken from 144 healthy volunteers aged 18 - 65 years. A questionnaire provided data of medication, medical history, vitamin supplementation, alcohol consumption, and use of oral contraceptives and others. Serum folate and vitamin B12 concentrations were measured on the Abbott Architect i2000. Reference values were calculated using the bootstrap method. Results of serum folate, vitamin B12, and homocysteine from 1190 individuals from regional primary health care centers were evaluated related to reference values and the proportion of individuals with deficiency was estimated. Mean serum concentrations of folate and vitamin B12 were 11.9 nmol/L and 328 pmol/L, respectively. Men were found to have statistically significant higher vitamin B12 concentrations than women. 95%-reference intervals were calculated to 5.2 - 29.2 nmol/L for folate and 133 - 595 pmol/L for vitamin B12. 1.1% of the study population has serum vitamin B12-concentrations vitamin B12 for a healthy, not vitamin-supplemented adult population were determined from 144 subjects. The application of these intervals will assist in the evaluation of folate and vitamin status.

  1. Vitamin B12 Phosphate Conjugation and Its Effect on Binding to the Human B12 -Binding Proteins Intrinsic Factor and Haptocorrin

    DEFF Research Database (Denmark)

    Ó Proinsias, Keith; Ociepa, Michał; Pluta, Katarzyna

    2016-01-01

    The binding of vitamin B12 derivatives to human B12 transporter proteins is strongly influenced by the type and site of modification of the cobalamin original structure. We have prepared the first cobalamin derivative modified at the phosphate moiety. The reaction conditions were fully optimized...... and its limitations examined. The resulting derivatives, particularly those bearing terminal alkyne and azide groups, were isolated and used in copper-catalyzed alkyne-azide cycloaddition reactions (CuAAC). Their sensitivity towards light revealed their potential as photocleavable molecules. The binding...

  2. Ultrasonographic evaluation to diagnose hepatic lipidosis in Egyptian Zaraibi goats with vitamin B12 deficiency

    Directory of Open Access Journals (Sweden)

    Sabry A. El-Khodery

    2011-01-01

    Full Text Available As little is known about the ultrasonographic features of hepatic lipidosis (white liver disease in goats, this study was undertaken to evaluate the use of ultrasound for the diagnosis of hepatic lipidosis associated with vitamin B12 (cyanocobalamin deficiency in Egyptian Zaraibi goats. A total of 38 goats (28 with weight loss, diarrhoea and anaemia and 10 clinically healthy were studied. Twenty-one goats were demonstrated to have cobalt and cyanocobalamin deficiency (0.33 ± 0.12 μmol/l and 0.17 ± 0.10 μg/l, respectively. Goats were examined with a real-time ultrasound system using a 5-MHz convex transducer. Ultrasound-guided liver biopsies and blood samples were obtained from each animal at examination. Based on the histopathological findings, diseased goats were classified as having mild (n = 6, moderate (n = 6 or severe lipidosis (n = 9. Ultrasonographic-hepatic changes were recorded in 19 (90.4% out of 21 goats. Severe lipidosis showed diffuse hyper-echogenicity of hepatic parenchyma. However, focal hyper-echoic lesions with various shapes, sizes and positions were visualized in mild and moderate lipidosis. Liver size increased significantly (P < 0.05 in severely affected goats compared with the controls. Histopathologically, macrovacuolations, congestion of hepatic sinusoids and infiltration of the portal area with inflammatory cells and connective tissues were evident in moderate and severely affected cases. There were varying degrees of anaemia, hypoglycemia and hypoproteinemia with significant increases (P < 0.05 of aspartate aminotransferase (AST and alkaline phosphatase (ALP in diseased animals compared with the controls. In conclusion, ultrasound may be a useful diagnostic tool in goats with suspected hepatic lipidosis associated with vitamin B12 deficiency.

  3. Enhancement Factors in Ozone Absorption Based on the Surface Renewal Model and its Application

    Institute of Scientific and Technical Information of China (English)

    程江; 杨卓如; 陈焕钦; C.H.Kuo; M.E.Zappi

    2000-01-01

    Based on the Danckwerts surface renewal model, a simple explicit expression of the enhancement factor in ozone absorption with a first order ozone self-decomposition and parallel second order ozonation reactions has been derived. The results are compared with our previous work based on the film theory. The 2,4-dichlorophenol destruction rate by ozonation is predicted using the enhancement factor model in this paper.

  4. Vitamin B12 Production by Marine Bacteria in Organic Substrate Limited, Slow Growth Conditions

    Science.gov (United States)

    Villegas-Mendoza, J.; Cajal-Medrano, R.; Maske, H.

    2016-02-01

    The conditions and processes governing the B12 vitamin dissemination through planktonic organisms are little understood. It is generally assumed that bacteria produce B12 vitamin and the whole auxotrophic plankton community consumes it. We used natural marine bacteria communities and marine bacteria Dinoroseobacter shibae cultures, growing in substrate-limited continuous cultures at low specific growth rates [0.1 to 1 d-1] to measure intracellular and dissolved B12 production, bacterial and viral abundance, particulate organic carbon, and nitrogen, bacterial production, oxygen consumption, carbon dioxide production, ETS activity, and taxonomic composition. We find dissolved B12 vitamin at concentrations between 0 to 1.4 pM with no relation to growth or respiration rates. The intracellular B12 vitamin normalized to cell volume ranged between 1x10-2 to 4.6x10-2 pmol μm3 showing a significant relationship with growth rate [y=0.02(m)1.07; r2=0.78; p≤0.05; y=intracellular B12 production, pmol μm3 day-1; m=specific growth rate, day-1], and respiration rates [y=2.4ln(x)-2.66; r2=0.87; p≤0.05; x=CO2 production, μM day-1]. The vitamin B12 producing bacteria D. shibae, showed a dissolved B12 concentration between 0 and 1.8 pM, whereas intracellular B12 normalized to cell volume varied between 1.1x10-2 to 1.8x10-2 pmol μm-3, responding significantly to growth rate [y=0.01(m)0.56; r2=0.85; p≤0.05], and to respiration rates [y=3.01ln(x)-7.56, r2=0.97, p≤0.05; x=CO2 production, μM day-1]. The lack of correlation of dissolved B12 vitamin with the metabolic activity suggests that the dissolved B12 concentration depends on the interactions among vitamin B12 producers and consumers while the bacterial metabolism is regulating the intracellular production of B12 vitamin.

  5. Estimation of lunar titanium content: Based on absorption features of Chang’E-1 interference imaging spectrometer (ⅡM)

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Two linear regression models based on absorption features extracted from CE-1 IIM image data are presented to discuss the relationship between absorption features and titanium content. We computed five absorption parameters (Full Wave at Half Maximum (FWHM), absorption position, absorption area, absorption depth and absorption asymmetry) of the spectra collected at Apollo 17 landing sites to build two regression models, one with FWHM and the other without FWHM due to the low relation coefficient between FWHM and Ti content. Finally Ti content measured from Apollo 17 samples and Apollo 16 samples was used to test the accuracy. The results show that the predicted values of the model with FWHM have many singular values and the result of model without FWHM is more stable. The two models are relatively accurate for high-Ti districts, while seem inexact and disable for low-Ti districts.

  6. Vitamin B(12) deficiency stimulates osteoclastogenesis via increased homocysteine and methylmalonic acid.

    Science.gov (United States)

    Vaes, Bart L T; Lute, Carolien; Blom, Henk J; Bravenboer, Nathalie; de Vries, Teun J; Everts, Vincent; Dhonukshe-Rutten, Rosalie A; Müller, Michael; de Groot, Lisette C P G M; Steegenga, Wilma T

    2009-05-01

    The risk of nutrient deficiencies increases with age in our modern Western society, and vitamin B(12) deficiency is especially prevalent in the elderly and causes increased homocysteine (Hcy) and methylmalonic acid (MMA) levels. These three factors have been recognized as risk factors for reduced bone mineral density and increased fracture risk, though mechanistic evidence is still lacking. In the present study, we investigated the influence of B(12), Hcy, and MMA on differentiation and activity of bone cells. B(12) deficiency did not affect the onset of osteoblast differentiation, maturation, matrix mineralization, or adipocyte differentiation from human mesenchymal stem cells (hMSCs). B(12) deficiency caused an increase in the secretion of Hcy and MMA into the culture medium by osteoblasts, but Hcy and MMA appeared to have no effect on hMSC osteoblast differentiation. We further studied the effect of B(12), Hcy, and MMA on the formation of multinucleated tartrate-resistant acid phosphatase-positive osteoclasts from mouse bone marrow. We observed that B(12) did not show an effect on osteoclastogenesis. However, Hcy as well as MMA were found to induce osteoclastogenesis in a dose-dependent manner. On the basis of these results, we conclude that B(12) deficiency may lead to decreased bone mass by increased osteoclast formation due to increased MMA and Hcy levels.

  7. Is vitamin B12 deficiency a risk factor for cardiovascular disease in vegetarians?

    Science.gov (United States)

    Pawlak, Roman

    2015-06-01

    The goal of this paper is to describe the role of vitamin B12 deficiency in cardiovascular disease development among vegetarians. Vegetarians have a high prevalence of vitamin B12 deficiency. Deficiency of this vitamin is associated with a variety of atherogenic processes that are mainly, but not exclusively, due to vitamin B12 deficiency-induced hyperhomocysteinemia. Each 5-μmol/L increase above 10 μmol/L of serum homocysteine is associated with a 20% increased risk of circulatory health problems. Mean homocysteine concentration >10 μmol/L among vegetarians was reported in 32 of 34 reports. Macrocytosis associated with vitamin B12 deficiency is also associated with fatal and non-fatal coronary disease, myocardial infarction, stroke, and other circulatory health problems. Compared with non-vegetarians, vegetarians have an improved profile of the traditional cardiovascular disease risk factors, including serum lipids, blood pressure, serum glucose concentration, and weight status. However, not all studies that assessed cardiovascular disease incidence among vegetarians reported a protective effect. Among studies that did show a lower prevalence of circulatory health problems, the effect was not as pronounced as expected, which may be a result of poor vitamin B12 status due to a vegetarian diet. Vitamin B12 deficiency may negate the cardiovascular disease prevention benefits of vegetarian diets. In order to further reduce the risk of cardiovascular disease, vegetarians should be advised to use vitamin B12 supplements. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  8. Possible undercompensation effect in the Kondo insulator (Yb,Tm)B12

    Science.gov (United States)

    Alekseev, P. A.; Nemkovski, K. S.; Mignot, J.-M.; Clementyev, E. S.; Ivanov, A. S.; Rols, S.; Bewley, R. I.; Filipov, V. B.; Shitsevalova, N. Yu.

    2014-03-01

    The effects of Tm substitution on the dynamical magnetic response of Yb1-xTmxB12 (x=0, 0.08, 0.15, and 0.75) and Lu0.92Tm0.08B12 compounds have been studied using time-of-flight inelastic neutron scattering. Major changes were observed in the spectral structure and temperature evolution of the Yb contribution to the inelastic response for a rather low content of magnetic Tm ions. A sizable influence of the RB12 host (YbB12, as compared to LuB12 or pure TmB12) on the crystal-field splitting of the Tm3+ ion is also reported. The results point to a specific effect of impurities carrying a magnetic moment (Tm, as compared to Lu or Zr) in a Kondo insulator, which is thought to reflect the "undercompensation" of Yb magnetic moments, originally Kondo screened in pure YbB12. A parallel is made with the strong effect of Tm substitution on the temperature dependence of the Seebeck coefficient in Yb1-xTmxB12, which was reported previously.

  9. Mathematical Modeling of Glutathione Status in Type 2 Diabetics with Vitamin B12 Deficiency.

    Science.gov (United States)

    Karamshetty, Varun; Acharya, Jhankar D; Ghaskadbi, Saroj; Goel, Pranay

    2016-01-01

    Deficiencies in vitamin B12 and glutathione (GSH) are associated with a number of diseases including type 2 diabetes mellitus. We tested newly diagnosed Indian diabetic patients for correlation between their vitamin B12 and GSH, and found it to be weak. Here we seek to examine the theoretical dependence of GSH on vitamin B12 with a mathematical model of 1-carbon metabolism due to Reed and co-workers. We study the methionine cycle of the Reed-Nijhout model by developing a simple "stylized model" that captures its essential topology and whose kinetics are analytically tractable. The analysis shows-somewhat counter-intuitively-that the flux responsible for the homeostasis of homocysteine is, in fact, peripheral to the methionine cycle. Elevation of homocysteine arises from reduced activity of methionine synthase, a vitamin B12-dependent enzyme, however, this does not increase GSH biosynthesis. The model suggests that the lack of vitamin B12-GSH correlation is explained by suppression of activity in the trans-sulfuration pathway that limits the synthesis of cysteine and GSH from homocysteine. We hypothesize this "cysteine-block" is an essential consequence of vitamin B12 deficiency. It can be clinically relevant to appreciate that these secondary effects of vitamin B12 deficiency could be central to its pathophysiology.

  10. Vitamin B12, folate, homocysteine and urinary methylmalonic acid levels in infants.

    Science.gov (United States)

    Karademir, F; Suleymanoglu, S; Ersen, A; Aydinoz, S; Gultepe, M; Meral, C; Ozkaya, H; Gocmen, I

    2007-01-01

    Serum vitamin B12 and folate, and their functional markers, plasma homocysteine and urinary methylmalonate (uMMA) were measured in 204 healthy, term infants at birth, and at 2 and 6 months. Compared with infants receiving formula food, those fed mother's milk had lower vitamin B12 and folate at 2 and 6 months. In infants receiving mother's milk, vitamin B12 levels were similar at birth (238 pg/ml) and 2 months (243 pg/ml), whereas with formula milk the level was significantly higher at 2 months (558 pg/ml) than at birth (257 pg/ml). Vitamin B12 was negatively correlated with homocysteine at birth and 6 months. The level of uMMA (mmol/mol creatinine) was higher at 2 (mother's milk, 25.5; formula, 23.97) and 6 months (19.77; 15) than at birth (11.97; 10.88), and was not correlated with vitamin B12 levels. Homocysteine may be a reliable marker of vitamin B12 status in neonates and infants; however, uMMA is not suitable as a marker of vitamin B12 status.

  11. Subjective well-being in older adults: folate and vitamin B12 independently predict positive affect.

    Science.gov (United States)

    Edney, Laura C; Burns, Nicholas R; Danthiir, Vanessa

    2015-10-28

    Vitamin B12, folate and homocysteine have long been implicated in mental illness, and growing evidence suggests that they may play a role in positive mental health. Elucidation of these relationships is confounded due to the dependence of homocysteine on available levels of vitamin B12 and folate. Cross-sectional and longitudinal relationships between vitamin B12, folate, homocysteine and subjective well-being were assessed in a sample of 391 older, community-living adults without clinically diagnosed depression. Levels of vitamin B12, but not folate, influenced homocysteine levels 18 months later. Vitamin B12, folate and their interaction significantly predicted levels of positive affect (PA) 18 months later, but had no impact on the levels of negative affect or life satisfaction. Cross-sectional relationships between homocysteine and PA were completely attenuated in the longitudinal analyses, suggesting that the cross-sectional relationship is driven by the dependence of homocysteine on vitamin B12 and folate. This is the first study to offer some evidence of a causal link between levels of folate and vitamin B12 on PA in a large, non-clinical population.

  12. Associations between Folate and Vitamin B12 Levels and Inflammatory Bowel Disease: A Meta-Analysis.

    Science.gov (United States)

    Pan, Yun; Liu, Ya; Guo, Haizhuo; Jabir, Majid Sakhi; Liu, Xuanchen; Cui, Weiwei; Li, Dong

    2017-04-13

    Inflammatory bowel disease (IBD) patients may be at risk of vitamin B12 and folate insufficiencies, as these micronutrients are absorbed in the small intestine, which is affected by IBD. However, a consensus has not been reached on the association between IBD and serum folate and vitamin B12 concentrations. In this study, a comprehensive search of multiple databases was performed to identify studies focused on the association between IBD and serum folate and vitamin B12 concentrations. Studies that compared serum folate and vitamin B12 concentrations between IBD and control patients were selected for inclusion in the meta-analysis. The main outcome was the mean difference in serum folate and vitamin B12 concentrations between IBD and control patients. Our findings indicated that the average serum folate concentration in IBD patients was significantly lower than that in control patients, whereas the mean serum vitamin B12 concentration did not differ between IBD patients and controls. In addition, the average serum folate concentration in patients with ulcerative colitis (UC) but not Crohn's disease (CD) was significantly lower than that in controls. This meta-analysis identified a significant relationship between low serum folate concentration and IBD. Our findings suggest IBD may be linked with folate deficiency, although the results do not indicate causation. Thus, providing supplements of folate and vitamin B12 to IBD patients may improve their nutritional status and prevent other diseases.

  13. Neurology of Nutritional Vitamin B12 Deficiency in Infants: Case Series From India and Literature Review.

    Science.gov (United States)

    Goraya, Jatinder Singh; Kaur, Sukhjot; Mehra, Bharat

    2015-11-01

    We studied 27 infants aged 6 to 27 months with vitamin B12 deficiency also known as "infantile tremor syndrome" in India. All were exclusively breast-fed by vegetarian mothers. Developmental delay or regression, pallor, skin hyperpigmentation, and sparse brown hair were present in all. Majority were hypotonic and involuntary movements were encountered in 18. Anemia and macrocytosis was found in 83% and 71% infants, respectively. Low serum vitamin B12 was present in 12 of 21 infants. Seven of the 9 infants with normal serum vitamin B12 had received vitamin B12 before referral. Twelve mothers had low serum vitamin B12. Cerebral atrophy was present in all the 9 infants who underwent neuroimaging. Treatment with vitamin B12 resulted in dramatic improvement in general activity and appetite within 48 to 72 hours followed by return of lost milestones. Tremors resolved in all by 3 to 4 weeks. Nutritional vitamin B12 deficiency is a treatable cause of neurologic dysfunction in infants. © The Author(s) 2015.

  14. Paraoxonase and arylesterase activities in adults with vitamin B12 deficiency.

    Science.gov (United States)

    Guney, Tekin; Alisik, Murat; Alkan, Afra; Basturk, Abdulkadir; Akinci, Sema; Hacibekiroglu, Tuba; Dilek, Imdat; Erel, Ozcan

    2015-09-12

    Objective The purpose of this study was to investigate paraoxonase (PON) and arylesterase (ARES) enzyme activity in adults with vitamin B12 deficiency, and specific changes in the activities of these enzymes following vitamin B12 treatment. Methods A total of 46 patients with vitamin B12 deficiency (aged 18-82 years) and 45 healthy volunteer controls (aged 19-64 years) participated in this study. Venous blood samples were collected, and serum vitamin B12, homocysteine (HCY), methylmalonic acid, PON1, and ARES levels were measured. Results Paired comparison showed that pre- and post-treatment values for PON and ARES were similar between patients and controls (both P > 0.05). There was no statistically significant relationship between patients' pre-/post-treatment PON or HCY levels and serum vitamin B12 levels, compared with those of the control group (P > 0.05). Discussion The results of the present study do not support the hypothesis that the antioxidant enzymes PON and ARES have an underlying role in vitamin B12 deficiency and related hyperhomocysteinemia. Our findings suggest that PON and ARES do not play a role in the systemic effects of vitamin B12 deficiency.

  15. Blood folic acid, vitamin B12, and homocysteine levels in pregnant women with fetal growth restriction.

    Science.gov (United States)

    Jiang, H L; Cao, L Q; Chen, H Y

    2016-12-19

    Deficiencies in nutrients such as folic acid and vitamin B12 may play a role in fetal growth restriction (FGR). However, whether folic acid, vitamin B12, or homocysteine is associated with FGR in Chinese populations remains unclear. This study investigated the relationship between these nutrient deficiencies and FGR in pregnant Chinese women. We selected 116 mother and infant pairs, and categorized the neonates into the FGR, appropriate for gestational age, and large for gestational age groups. Birth weight, body length, head circumference, body mass index (BMI), and Rohrer's body index of the newborns were measured. Serum folic acid, vitamin B12, and homocysteine levels were measured in mothers during the first three days of their hospital stay. Results showed that the FGR group exhibited reduced folic acid and vitamin B12 levels and elevated homocysteine levels than those in the other two groups. Folic acid and vitamin B12 levels were positively correlated with birth weight, head circumference, and BMI, whereas homocysteine level was negatively correlated with these variables. The FGR ratio in the folic acid and vitamin B12 deficiency group was higher than that in the sufficiency group (χ(2) = 4.717 and 4.437, P = 0.029 and 0.035, respectively). In addition, elevated homocysteine was associated with FGR (χ(2) = 5.366, P = 0.021). In conclusion, we found that folic acid and vitamin B12 deficiency was associated with elevated homocysteine levels, which may increase susceptibility to FGR.

  16. Neuropathy caused by B12 deficiency in a patient with ileal tuberculosis: A case report

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    Toosi Taraneh

    2008-03-01

    Full Text Available Abstract Introduction Vitamin B12 deficiency can result in macrocytic anemia. Neurologic abnormalities of B12 deficiency include sensory deficits, loss of deep tendon reflexes, movement disorders, neuropsychiatric changes and seizures. Segmental involvement of the distal ileum, such as in tuberculosis, can cause vitamin B12 deficiency. To our knowledge, macrocytic anemia with unusual manifestations such as brain atrophy and seizures due to intestinal tuberculosis has not been reported in the literature. Case presentation A 14-year-old girl presented with complaints of paraplegia, ataxia, fever and fatigue that had started a few months earlier and which had been getting worse in the last three weeks. Her laboratory results were indicative of macrocytic anemia with a serum B12 level Conclusion Vitamin B12 deficiency should be considered in patients with neurologic features such as paresthesia, sensory deficits, urinary incontinence, dysarthria, and ataxia. The underlying cause of B12 deficiency should be determined and treated to obviate the patients' need for long term vitamin B12 therapy.

  17. High vitamin B12 level and good treatment outcome may be associated in major depressive disorder

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    Tanskanen Antti

    2003-12-01

    Full Text Available Abstract Background Despite of an increasing body of research the associations between vitamin B12 and folate levels and the treatment outcome in depressive disorders are still unsolved. We therefore conducted this naturalistic prospective follow-up study. Our aim was to determine whether there were any associations between the vitamin B12 and folate level and the six-month treatment outcome in patients with major depressive disorder. Because vitamin B12 and folate deficiency may result in changes in haematological indices, including mean corpuscular volume, red blood cell count and hematocrit, we also examined whether these indices were associated with the treatment outcome. Methods Haematological indices, erythrocyte folate and serum vitamin B12 levels were determined in 115 outpatients with DSM-III-R major depressive disorder at baseline and serum vitamin B12 level again on six-month follow-up. The 17-item Hamilton Depression Rating Scale was also compiled, respectively. In the statistical analysis we used chi-squared test, Pearson's correlation coefficient, the Student's t-test, analysis of variance (ANOVA, and univariate and multivariate linear regression analysis. Results Higher vitamin B12 levels significantly associated with a better outcome. The association between the folate level and treatment outcome was weak and probably not independent. No relationship was found between haematological indices and the six-month outcome. Conclusion The vitamin B12 level and the probability of recovery from major depression may be positively associated. Nevertheless, further studies are suggested to confirm this finding.

  18. Hybrid Microfluidic Platform for Multifactorial Analysis Based on Electrical Impedance, Refractometry, Optical Absorption and Fluorescence

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    Fábio M. Pereira

    2016-10-01

    Full Text Available This paper describes the development of a novel microfluidic platform for multifactorial analysis integrating four label-free detection methods: electrical impedance, refractometry, optical absorption and fluorescence. We present the rationale for the design and the details of the microfabrication of this multifactorial hybrid microfluidic chip. The structure of the platform consists of a three-dimensionally patterned polydimethylsiloxane top part attached to a bottom SU-8 epoxy-based negative photoresist part, where microelectrodes and optical fibers are incorporated to enable impedance and optical analysis. As a proof of concept, the chip functions have been tested and explored, enabling a diversity of applications: (i impedance-based identification of the size of micro beads, as well as counting and distinguishing of erythrocytes by their volume or membrane properties; (ii simultaneous determination of the refractive index and optical absorption properties of solutions; and (iii fluorescence-based bead counting.

  19. Optical Absorption and Electron Injection of 4-(Cyanomethylbenzoic Acid Based Dyes: A DFT Study

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    Yuehua Zhang

    2015-01-01

    Full Text Available Density functional theory (DFT and time-dependent density functional theory (TDDFT calculations were carried out to study the ground state geometries, electronic structures, and absorption spectra of 4-(cyanomethylbenzoic acid based dyes (AG1 and AG2 used for dye-sensitized solar cells (DSSCs. The excited states properties and the thermodynamical parameters of electron injection were studied. The results showed that (a two dyes have uncoplanar structures along the donor unit and conjugated bridge space, (b two sensitizers exhibited intense absorption in the UV-Vis region, and (c the excited state oxidation potential was higher than the conduction band edge of TiO2 photoanode. As a result, a solar cell based on the 4-(cyanomethylbenzoic acid based dyes exhibited well photovoltaic performance. Furthermore, nine dyes were designed on the basis of AG1 and AG2 to improve optical response and electron injection.

  20. The C677T MTHFR genotypes influence the efficacy of B9 and B12 vitamins supplementation to lowering plasma total homocysteine in hemodialysis.

    Science.gov (United States)

    Achour, Ons; Elmtaoua, Sahbi; Zellama, Dorsaf; Omezzine, Asma; Moussa, Amira; Rejeb, Jihene; Boumaiza, Imene; Bouacida, Lobna; Rejeb, Nabila Ben; Achour, Abdellatif; Bouslama, Ali

    2016-10-01

    Hyperhomocysteinaemia, an independent risk factor for cardiovascular diseases, is common in hemodialysis patients (HD) and particularly in those homozygous for polymorphism of the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene. B vitamins supplementation has been shown to lower plasma total homocysteine (tHcy), but this has been contreversed in several groups. The aim of our study was to explore the response of tHcy in hemodialysis (HD) patients to individual supplementation with folic acid (B9) and/or vitamin B12, based on carrier status for the (MTHFR) polymorphism. 132HD were randomized according to C677TMTHFR genotypes into 2 groups (AandB). The group (A) was treated initially with B9 (10mg/day orally) for 2 months (t1) and then with B12 vitamin (cyanocobalamin ampoule of 1000 μg) for the following 2 months (t2), then association of B9 and B12 for 2 months (t3). The group (B) was supplemented initially with vitamin B12 (t1), then with folic acid (t2) and then B9 + B12 for 2 months (t3). A wash-out period of 2 months followed the treatment in both groups (t4). We determined tHcy, B9 and B12 concentrations at each time. In group A, we noted that the decrease in tHcy becomes significant for CC when patients were supplemented with vit B12 only (p = 0.009). While, B9 + vit B12 supplementation did not seem to improve a significant effect compared with B12 alone. For genotypes (CT) and (TT) we noticed a significant decrease in tHcy at t1 (p = 0.038; 0.005 respectively) and at (t3; CT p = 0.024; TT p = 0.017). In group B, for genotypes CC, the decrease in tHcy became significant at t3 (vit B12 + B9; p = 0.031). For genotypes (CT) and (TT), at the replacement of vit B12 by B9, tHcy was significantly decreased (p = 0.036; 0.012, respectively). The combination of the 2 vitamins (t3) showed no difference compared to folate alone. In the 2 groups (t4), there was an significant increase of tHcy again for 3 genotypes. Supplementation with B

  1. Child's homocysteine concentration at 2 years is influenced by pregnancy vitamin B12 and folate status.

    Science.gov (United States)

    Lubree, H G; Katre, P A; Joshi, S M; Bhat, D S; Deshmukh, U S; Memane, N S; Otiv, S R; Rush, E C; Yajnik, C S

    2012-02-01

    Longitudinal studies investigating vitamin B12 and folate status of mothers and their offspring will provide a better understanding of intergenerational nutrition. During pregnancy and 2 years (2y) after delivery, we measured plasma vitamin B12 and folate concentrations in 118 women [aged (mean ± s.d.) 22.9 ± 3.9y] who attended a rural (n = 68) or an urban (n = 50) antenatal clinic in Pune, India. Cord blood vitamin B12 and folate were measured, and when the child was 2y total homocysteine (tHcy) was also measured. Demographic and diet measurements were recorded using standard methods. Pregnancy plasma vitamin B12 concentration at 34 weeks was low [median (25th, 75th), 115 (95, 147) pm]; 75% had low status (vitamin B12 and folate concentrations were higher than and positively associated with maternal concentrations. In stepwise regression, higher child vitamin B12 at 2y was predicted (total R 2 15.7%) by pregnancy vitamin B12 (std β 0.201, R 2 7.7%), current consumption of cow's milk (std β 0.194, R 2 3.3%) and whether breast feeding was stopped before 2y (std β -0.234 R 2 7.2%). Child's 2y tHcy concentration was high (11.4 ± 3.6 μm) and predicted by lower pregnancy vitamin B12 (std β -0.206, R 2 4.1%), lack of vitamin supplementation (std β -0.256, R 2 5.6%) in pregnancy and whether currently breastfed (std β 0.268, R 2 8.4%). Low maternal vitamin B12 status in pregnancy and prolonged breast-feeding results in disturbed one-carbon metabolism in offspring at 2y. Supplementation of women of child-bearing age, particularly during pregnancy and lactation, may improve the homocysteine status of these children.

  2. Treatment of confirmed B12 deficiency in hemodialysis patients improves Epogen® requirements

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    Saifan C

    2013-06-01

    Full Text Available Chadi Saifan, Mark Samarneh, Norbert Shtaynberg, Rabih Nasr, Elie El-Charabaty, Suzanne El-Sayegh Division of Nephrology, Staten Island University Hospital, Staten Island, NY, USA Background: Vitamin B12 deficiency may have deleterious effects on end stage renal disease (ESRD patients on maintenance hemodialysis, and may increase erythropoietin stimulating agent (ESA resistance, yet little is known about its prevalence in this population. Methods: Serum Vitamin B12 and methylmalonic acid (MMA levels were drawn from ESRD patients prior to hemodialysis. All patients with MMA levels greater than 800 nmol/L had peripheral smears evaluated for B12 deficiency. Those with confirmatory smears were considered to be deficient and received intramuscular vitamin B12 injections for 4 months. Post-treatment MMA levels and smears were obtained. Erythropoietin dosages were monitored throughout the treatment period. Results: There was a 58% (60/103 prevalence of vitamin B12 deficiency as defined by a positive MMA level and a positive blood smear. Out of 52 patients with positive smears, 36 (69.2% were negative on repeat analysis after B12 treatment. Mean Epogen® (EPO dosages significantly decreased by 16,572 ± 41,902 units per month from baseline to the post-B12 treatment period (P = 0.0082, Wilcoxon signed-rank test. Three months prior to treatment, the mean monthly EPO dose was 82,067 ± 47,906 and post, the mean EPO usage was 65,495 ± 39,691. Post treatment hemoglobin levels were not significantly different from baseline. Conclusion: Vitamin B12 supplementation was associated with a decrease in the mean dose of ESA administration while maintaining a stable hemoglobin level. Maintaining serum vitamin B12 levels improves functionality, and may allow a decrease in the use of ESA’s, avoiding their toxicities and significant costs. Keywords: ESRD, end stage renal disease, chronic kidney disease, anemia, vitamin deficiency, erythropoietin, dialysis

  3. Comparison Between Different Intramuscular Vitamin B12 Supplementation Regimes: a Retrospective Matched Cohort Study.

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    Smelt, H J M; Pouwels, S; Said, M; Berghuis, K A; Boer, A K; Smulders, J F

    2016-12-01

    The incidence of vitamin B12 deficiency after bariatric surgery can range from 26 to 70 %. There is no consensus on optimal vitamin B12 supplementation in postbariatric patients. The objective of this study was to compare three different regimes. In this retrospective matched cohort study, we included 63 patients with methylmalonic acid (MMA) levels ≥300 nmol/L. Group A (n = 21) received 6 intramuscular (im) vitamin B12 injections including a loading dose, group B (n = 21) received 3 im vitamin B12 injections without loading dose and group C (n = 21) received no im vitamin B12 injections. The total post-bariatric patient population consisted of 14 males (22.2 %) and 49 women (77.8 %) with a mean current body mass index of 30.6 ± 8.0 kg/m(2). There was no significant difference in vitamin B12 and MMA levels between 3 groups at baseline. There was a significant difference in follow-up vitamin B12 levels of group A compared to group B (p = 0.02) and group A compared to group C (p = 0.03). In the follow-up results, there is also a significant decrease in MMA levels of group A compared to group B (p = 0.02), group A compared to group C (p vitamin B12 deficiency. An injection regime with 6 injections recovered all vitamin B12 deficiencies biochemically. MMA levels cannot recover spontaneously over time without additional im injection regime.

  4. Therapeutic role of Vitamin B12 in patients of chronic tinnitus: A pilot study.

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    Singh, Charu; Kawatra, Rahul; Gupta, Jaya; Awasthi, Vishnu; Dungana, Homnath

    2016-01-01

    True tinnitus is a phantom auditory perception arising from a source or trigger in the cochlea, brainstem, or at higher centers and has no detectable acoustic generator. The most accepted is the famous neurophysiologic model of Jastreboff, which stresses that tinnitus, is a subcortical perception and results from the processing of weak neural activity in the periphery. The aim of this study is to determine the role of Vitamin B12 in treatment of chronic tinnitus. In this randomized, double-blind pilot study, total 40 patients were enrolled, of which 20 in Group A (cases) received intramuscular therapy of 1 ml Vitamin B12 (2500 mcg) weekly for a period of 6 weeks and Group B (20) patients received placebo isotonic saline 01 ml intramuscular. The patients were subjected to Vitamin B12 assay and audiometry pre- and post-therapy. Of the total patients of tinnitus, 17 were Vitamin B12 deficient that is 42.5% showed deficiency when the normal levels were considered to be 250 pg/ml. A paired t-test showed that in Group A, patients with Vitamin B12 deficiency showed significant improvement in mean tinnitus severity index score and visual analog scale (VAS) after Vitamin B12 therapy. This pilot study highlights the significant prevalence of Vitamin B12 deficiency in North Indian population and improvement in tinnitus severity scores and VAS in cobalamin-deficient patients receiving intramuscular Vitamin B12 weekly for 6 weeks further provides a link between cobalamin deficiency and tinnitus thereby suggestive of a therapeutic role of B12 in cobalamin-deficient patients of tinnitus.

  5. Serum folate, vitamin B12 and cognitive impairment in Chilean older adults.

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    Castillo-Lancellotti, Cecilia; Margozzini, Paula; Valdivia, Gonzalo; Padilla, Oslando; Uauy, Ricardo; Rozowski, Jaime; Tur, Josep A

    2015-10-01

    To analyse the relationship between serum folate (SF), vitamin B12 and impaired cognitive function in the Chilean elderly. We analysed the relationships between impaired cognitive function and age, SF (µg/l) and vitamin B12 (pg/ml) with Student's t test, as well as between impaired cognitive function and gender, educational level, residence area, diabetes and hypertension with the χ 2 test. Multiple logistic regressions with interactions were estimated to assess the impact of SF on impaired cognitive function according to these methods. Chile. Older adults (>65 years, n 1051), drawn from representative households of a national prevalence study, assessed using the Modified Mini Mental Status Examination (MMMSE). Individuals with altered MMMSE scores (≤13 points) were sequentially assessed using the Pfeffer Functional Activities Questionnaire (PFAQ). Multivariate models using the MMMSE demonstrated an increased risk of impaired cognitive function for seniors who had hypertension, diabetes and higher vitamin B12 levels. SF and its square (SF2) were statistically significant, indicating that this predictor of impaired cognitive function displays a U-shaped distribution. The interaction between SF and vitamin B12 was not statistically significant. Models using the MMMSE plus PFAQ suggested that urban residence decreased the risk of impaired cognitive function, whereas male gender, older age, vitamin B12 levels and hypertension increased this risk. The variables SF and SF2 and the SF × vitamin B12 interaction were statistically significant (Pvitamin B12 levels. When SF was low, a one-unit increase in SF (1 µg/l) diminished the risk. When SF was elevated, a further increase in SF raised the risk, especially at low vitamin B12 levels. The relationship between folate, vitamin B12 and impaired cognitive function warrants further study.

  6. Therapeutic role of Vitamin B12 in patients of chronic tinnitus: A pilot study

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    Charu Singh

    2016-01-01

    Full Text Available True tinnitus is a phantom auditory perception arising from a source or trigger in the cochlea, brainstem, or at higher centers and has no detectable acoustic generator. The most accepted is the famous neurophysiologic model of Jastreboff, which stresses that tinnitus, is a subcortical perception and results from the processing of weak neural activity in the periphery. The aim of this study is to determine the role of Vitamin B12 in treatment of chronic tinnitus. In this randomized, double-blind pilot study, total 40 patients were enrolled, of which 20 in Group A (cases received intramuscular therapy of 1 ml Vitamin B12 (2500 mcg weekly for a period of 6 weeks and Group B (20 patients received placebo isotonic saline 01 ml intramuscular. The patients were subjected to Vitamin B12 assay and audiometry pre- and post-therapy. Of the total patients of tinnitus, 17 were Vitamin B12 deficient that is 42.5% showed deficiency when the normal levels were considered to be 250 pg/ml. A paired t-test showed that in Group A, patients with Vitamin B12 deficiency showed significant improvement in mean tinnitus severity index score and visual analog scale (VAS after Vitamin B12 therapy. This pilot study highlights the significant prevalence of Vitamin B12 deficiency in North Indian population and improvement in tinnitus severity scores and VAS in cobalamin-deficient patients receiving intramuscular Vitamin B12 weekly for 6 weeks further provides a link between cobalamin deficiency and tinnitus thereby suggestive of a therapeutic role of B12 in cobalamin-deficient patients of tinnitus.

  7. High Prevalence of Vitamin B12 Deficiency and No Folate Deficiency in Young Children in Nepal

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    Bernadette N. Ng’eno

    2017-01-01

    Full Text Available Many children in low- and middle-income countries may have inadequate intake of vitamin B12 and folate; data confirming these inadequacies are limited. We used biochemical, demographic, behavioral and anthropometric data to describe the folate and vitamin B12 concentrations among six- to 23-month-old Nepalese children. Vitamin B12 (serum B12 < 150 pmol/L and folate deficiencies (red blood cell (RBC folate < 226.5 nmol/L were assessed. We used logistic regression to identify predictors of vitamin B12 deficiency. The vitamin B12 geometric mean was 186 pmol/L; 30.2% of children were deficient. The mean RBC folate concentration was 13,612 nmol/L; there was no deficiency. Factors associated with vitamin B12 deficiency included: (a age six to 11 months (adjusted odds ratio (aOR 1.51; 95% confidence interval (CI: 1.18, 1.92 or 12–17 months (aOR 1.38; 95% CI: 1.10, 1.72 compared to 18–23 months; (b being stunted (aOR 1.24; 95% CI: 1.03, 1.50 compared to not being stunted; (c and not eating animal-source foods (aOR 1.85; 95% CI: 1.42, 2.41 compared to eating animal-source foods the previous day. There was a high prevalence of vitamin B12 deficiency, but no folate deficiency. Improving early feeding practices, including the consumption of rich sources of vitamin B12, such as animal-source foods and fortified foods, may help decrease deficiency.

  8. Intrinsic factor van castle en resorptie van vitamine B12 : een klinisch en experimenteel onderzoek met behulp van radioaktieve vitamine B12.

    NARCIS (Netherlands)

    Abels, Johannes

    1959-01-01

    Hoofdstuk I bevat enkele opmerkingen over de werking van vit.B12 met radioactieve kobalt isolopen. Bij toediening aan de mens geven wij voorkeur aan Co56 en Co58 op grond van hun relatief korte haveringstijden t.o.v. Co60. De vier gangbare metoden voor het meten van de resorptie van radioaktieve vit

  9. Vitamin B(12) dependent changes in mouse spinal cord expression of vitamin B(12) related proteins and the epidermal growth factor system

    DEFF Research Database (Denmark)

    Mutti, Elena; Lildballe, Dorte L; Kristensen, Lise

    2013-01-01

    Chronic vitamin B(12) (cobalamin) deficiency in the mammalian central nervous system causes degenerative damage, especially in the spinal cord. Previous studies have shown that cobalamin status alters spinal cord expression of epidermal growth factor (EGF) and its receptor in rats. Employing a mo...

  10. Combined vitamin B-12 and balanced protein-energy supplementation affect homocysteine remethylation in the methionine cycle in pregnant south Indian women of low vitamin B-12 status

    Science.gov (United States)

    Low-quality dietary protein intake and vitamin B-12 deficiency could interact to decrease methionine transmethylation and remethylation rates during pregnancy, and may affect epigenetic modifications of the fetal genome. The objective of this randomized, partially open-labeled intervention trial was...

  11. Folate Deficiency Is Prevalent in Women of Childbearing Age in Belize and Is Negatively Affected by Coexisting Vitamin B-12 Deficiency: Belize National Micronutrient Survey 2011.

    Science.gov (United States)

    Rosenthal, Jorge; Largaespada, Natalia; Bailey, Lynn B; Cannon, Michael; Alverson, C J; Ortiz, Dayrin; Kauwell, Gail Pa; Sniezek, Joe; Figueroa, Ramon; Daly, Robyn; Allen, Peter

    2017-06-01

    Background: Folate deficiency, vitamin B-12 deficiency, and anemia can have adverse effects on birth outcomes. Also, low vitamin B-12 reduces the formation of metabolically active folate.Objectives: We sought to establish the baseline prevalence of and factors associated with folate deficiency and insufficiency, vitamin B-12 deficiency, and anemia among women of childbearing age (WCBA) in Belize.Methods: In 2011, a national probability-based survey was completed among Belizean nonpregnant WCBA aged 15-49 y. Blood samples for determination of hemoglobin, folate (RBC and serum), and vitamin B-12 (plasma) and sociodemographic and health information were collected from 937 women. RBC and serum folate concentrations were measured by microbiologic assay (MBA). Folate status was defined based on both the WHO-recommended radioproteinbinding assay and the assay adjusted for the MBA.Results: The national prevalence estimates for folate deficiency in WCBA, based on serum and RBC folate concentrations by using the assay-matched cutoffs, were 11.0% (95% CI: 8.6%, 14.0%) and 35.1% (95% CI: 31.3%, 39.2%), respectively. By using the assay-matched compared with the WHO-recommended cutoffs, a substantially higher prevalence of folate deficiency was observed based on serum (6.9% absolute difference) and RBC folate (28.9% absolute difference) concentrations. The prevalence for RBC folate insufficiency was 48.9% (95% CI: 44.8%, 53.1%). Prevalence estimates for vitamin B-12 deficiency and marginal deficiency and anemia were 17.2% (95% CI: 14.2%, 20.6%), 33.2% (95% CI: 29.6%, 37.1%), and 22.7% (95% CI: 19.5%, 26.2%), respectively. The adjusted geometric means of the RBC folate concentration increased significantly (P-trend vitamin B-12 status relative to WCBA who were vitamin B-12 deficient.Conclusions: In Belize, the prevalence of folate and vitamin B-12 deficiencies continues to be a public health concern among WCBA. Furthermore, low folate status co-occurred with low vitamin B-12

  12. 食品中维生素B12的测定

    Institute of Scientific and Technical Information of China (English)

    姜淑云; 徐兰

    2004-01-01

    维生素B12——氰钴胺,是人体必需的微量营养成分之一,可助人体对铁的代谢及对血红蛋白的合成具有重要的生理功能和临床意义。还有些专业人士认为维生素B12可以防止心血管疾病和白癜风疾病的发生。研究维生素B12检测方法,可用于检

  13. Genetic architecture of vitamin B12 and folate levels uncovered applying deeply sequenced large datasets

    DEFF Research Database (Denmark)

    Grarup, Niels; Sulem, Patrick; Sandholt, Camilla H;

    2013-01-01

    of the underlying biology of human traits and diseases. Here, we used a large Icelandic whole genome sequence dataset combined with Danish exome sequence data to gain insight into the genetic architecture of serum levels of vitamin B12 (B12) and folate. Up to 22.9 million sequence variants were analyzed in combined...... in serum B12 or folate levels do not modify the risk of developing these conditions. Yet, the study demonstrates the value of combining whole genome and exome sequencing approaches to ascertain the genetic and molecular architectures underlying quantitative trait associations....

  14. High Pressure X-ray Diffraction Study on Icosahedral Boron Arsenide (B12As2)

    Energy Technology Data Exchange (ETDEWEB)

    J Wu; H Zhu; D Hou; C Ji; C Whiteley; J Edgar; Y Ma

    2011-12-31

    The high pressure properties of icosahedral boron arsenide (B12As2) were studied by in situ X-ray diffraction measurements at pressures up to 25.5 GPa at room temperature. B12As2 retains its rhombohedral structure; no phase transition was observed in the pressure range. The bulk modulus was determined to be 216 GPa with the pressure derivative 2.2. Anisotropy was observed in the compressibility of B12As2-c-axis was 16.2% more compressible than a-axis. The boron icosahedron plays a dominant role in the compressibility of boron-rich compounds.

  15. Pernicious anemia presenting as catatonia: correlating vitamin B12 levels and catatonic symptoms.

    Science.gov (United States)

    Bram, Damien; Bubrovszky, Maxime; Durand, Jean-Paul; Lefevre, Guillaume; Morell-Dubois, Sandrine; Vaiva, Guillaume

    2015-01-01

    Pernicious anemia has been associated with various psychiatric manifestations, such as depression, mania and psychosis. Psychiatric symptoms can sometimes occur without hematological and neurological abnormalities and can be prodromal of vitamin B12 deficiency. We report a case of autoimmune B12 deficiency presenting as catatonia without signs of anemia or macrocytosis, in which a correlation was found between the patient's B12 blood levels and catatonic symptoms over time. This catatonic episode was successfully treated with only lorazepam and adequate doses of cyanocobalamin. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. INVESTIGATION OF SURFACE AND BULK PROCESSES IN MG-BASED ALLOYS DURING HYDROGEN ABSORPTION

    Directory of Open Access Journals (Sweden)

    Balázs Vehovszky

    2012-09-01

    Full Text Available Different Mg-based alloys were tailored and prepared to investigate the surface and bulk processes during hydrogen absorption. Volumetric-, resistance-, XRD-, optical-, and mass measurements were carried out. Heat treatment experiments showed that the short-term thermal stability limits (during heating up at 5 K/min of the amorphous samples were between 125-175 ° C, while long-term stability (during 24h heat treatment is always lower – between 80 and 150°C. Nanocrystalline alloys were stable up to 300°C. Hydrogen absorption measurements were executed between 25 and 300°C. Pd-containing alloys were found to be the fastest absorbers, and 200°C was the optimal temperature regarding absorption rate. Etching the samples previously in HF solution enhances absorption by inducing surface cracking. This phenomenon was thoroughly examined by optical microscopy. The effect of hydrogen on the crystallization properties of MgNiPd sample was determined via in-situ resistance measurements.

  17. Investigation of Surface and Bulk Processes in Mg-based Alloys during Hydrogen Absorption

    Directory of Open Access Journals (Sweden)

    Balázs Vehovszky

    2012-09-01

    Full Text Available Different Mg-based alloys were tailored and prepared to investigate the surface and bulk processes during hydrogen absorption. Volumetric-, resistance-, XRD-, optical-, and mass measurements were carried out. Heat treatment experiments showed that the short-term thermal stability limits (during heating up at 5 K/min of the amorphous samples were between 125-175 ° C, while long-term stability (during 24h heat treatment is always lower – between 80 and 150°C. Nanocrystalline alloys were stable up to 300°C. Hydrogen absorption measurements were executed between 25 and 300°C. Pd-containing alloys were found to be the fastest absorbers, and 200°C was the optimal temperature regarding absorption rate. Etching the samples previously in HF solution enhances absorption by inducing surface cracking. This phenomenon was thoroughly examined by optical microscopy. The effect of hydrogen on the crystallization properties of MgNiPd sample was determined via in-situ resistance measurements.

  18. Nonlinear absorption and optical damage threshold of carbon-based nanostructured material embedded in a protein

    Science.gov (United States)

    Janulewicz, K. A.; Hapiddin, A.; Joseph, D.; Geckeler, K. E.; Sung, J. H.; Nickles, P. V.

    2014-12-01

    Physical processes in laser-matter interaction used to be determined by generation of fast electrons resulting from efficient conversion of the absorbed laser radiation. Composite materials offer the possibility to control the absorption by choice of the host material and dopants. Reported here strong absorption of ultrashort laser pulse in a composite carbon-based nanomaterial including single-walled carbon nanotubes (SWCNTs) or multilayer graphene was measured in the intensity range between 1012 and 1016 W cm-2. A protein (lysozyme) was used as the host. The maximum absorption of femtosecond laser pulse has reached 92-96 %. The optical damage thresholds of the coatings were registered at an intensity of (1.1 ± 0.5) × 1013 W cm-2 for the embedded SWCNTs and at (3.4 ± 0.3) × 1013 W cm-2 for the embedded graphene. Encapsulated variant of the dispersed nanomaterial was investigated as well. It was found that supernatant protein in the coating material tends to dominate the absorption process, independently of the embedded nanomaterial. The opposite was observed for the encapsulated material.

  19. Carbon-Nanohorn Based Nanofluids for a Direct Absorption Solar Collector for Civil Application.

    Science.gov (United States)

    Moradi, A; Sani, E; Simonetti, M; Francini, F; Chiavazzo, E; Asinari, P

    2015-05-01

    Direct solar absorption has been often considered in the past as a possible solution for solar thermal collectors for residential and small commercial applications. A direct absorption could indeed improve the performance of solar collectors by skipping one step of the heat transfer mechanism in standard devices and having a more convenient temperature distribution inside the collector. Classical solar thermal collectors have a metal sheet as absorber, designed such that water has the minimum temperature in each transversal section, in order to collect as much solar thermal energy as possible. On the other hand, in a direct configuration, the hottest part of the system is the operating fluid and this allows to have a more efficient conversion. Nanofluids, i.e., fluids with a suspension of nanoparticles, such as carbon nanohorns, could be a good and innovative family of absorbing fluids owing to their higher absorption coefficient compared to the base fluid and stability under moderate temperature gradients. Moreover, carbon nanohorns offer the remarkable advantage of a reduced toxicity over other carbon nanoparticles. In this work, a three-dimensional model of the absorption phenomena in nanofluids within a cylindrical tube is coupled with a computational fluid dynamics (CFD) analysis of the flow and temperature field. Measured optical properties of nanofluids at different concentrations have been implemented in the model. Heat losses due to conduction, convection and radiation at the boundaries are considered as well.

  20. Space Launch System Base Heating Test: Tunable Diode Laser Absorption Spectroscopy

    Science.gov (United States)

    Parker, Ron; Carr, Zak; MacLean, Matthew; Dufrene, Aaron; Mehta, Manish

    2016-01-01

    This paper describes the Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurement of several water transitions that were interrogated during a hot-fire testing of the Space Launch Systems (SLS) sub-scale vehicle installed in LENS II. The temperature of the recirculating gas flow over the base plate was found to increase with altitude and is consistent with CFD results. It was also observed that the gas above the base plate has significant velocity along the optical path of the sensor at the higher altitudes. The line-by-line analysis of the H2O absorption features must include the effects of the Doppler shift phenomena particularly at high altitude. The TDLAS experimental measurements and the analysis procedure which incorporates the velocity dependent flow will be described.

  1. Mathematical Model of Fiber Optic Temperature Sensor Based on Optic Absorption and Experiment Testing

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    On the basis of analysis on the temperature monitoring methods for high voltage devices, a new type of fiber optic sensor structure with reference channel is given. And the operation principle of fiber optic sensor is analysed at large based on the absorption of semiconductor chip. The mathematical model of both devices and the whole system are also given. It is proved by the experiment that this mathematical model is reliable.

  2. Performance Evaluation of a Nanofluid-Based Direct Absorption Solar Collector with Parabolic Trough Concentrator

    OpenAIRE

    Xu, Guoying; Chen, Wei; Deng, Shiming; Zhang, Xiaosong; Zhao, Sainan

    2015-01-01

    Application of solar collectors for hot water supply, space heating, and cooling plays a significant role in reducing building energy consumption. For conventional solar collectors, solar radiation is absorbed by spectral selective coating on the collectors’ tube/plate wall. The poor durability of the coating can lead to an increased manufacturing cost and unreliability for a solar collector operated at a higher temperature. Therefore, a novel nanofluid-based direct absorption solar collector...

  3. Coordination chemistry and biological activity of 5'-OH modified quinoline-B12 derivatives.

    Science.gov (United States)

    Zelenka, Karel; Brandl, Helmut; Spingler, Bernhard; Zelder, Felix

    2011-10-14

    The consequences of structural modifications at the 5'-OH ribofuranotide moiety of quinoline modified B12 derivatives are discussed in regard of the coordination chemistry, the electrochemical properties and the biological behaviour of the compound.

  4. [Vitamin B12 deficiency associated with high doses od metformin in older people diabetic].

    Science.gov (United States)

    Sánchez, Hugo; Masferrer, Dominique; Lera, Lydia; Arancibia, Estrella; Angel, Barbara; Albala, Cecilia

    2014-06-01

    Introducción: El objetivo del estudio es estimar si el déficit de B12 se asocia con el uso de la metformina en adultos mayores (AM) diabéticos. Métodos: Estudio de casos y controles en AM diabéticos. Los casos (n = 137) se definieron como AM con B12 221 pmol/L. Se definieron 4 categorías de uso de metformina: no usuarios, ≤850 mg/día; > 850 y adultos mayores que consumían altas dosis de metformina presentaban 1,9 veces más riesgo de déficit de B12 (OR:1,9; 95%IC: 1,08-3,30). Conclusión: Estos resultados muestran una fuerte asociación entre altas dosis de metformina y niveles bajos de vitamina B12. Este proyecto fue financiado por FONIS SA11I2092.

  5. Vitamin B12 Deficiency in Persons with Intellectual Disability in a Vegetarian Residential Care Community

    Directory of Open Access Journals (Sweden)

    Mohammed Morad

    2005-01-01

    Full Text Available The goal of this study was to determine the prevalence of vitamin B12 deficiency among intellectually disabled persons in a vegetarian remedial community in Israel. In this community, 47 individuals with intellectual disability (ID live in 7 enlarged families in a kibbutz style agricultural setting. These 47 individuals and 17 of their caregivers were screened for vitamin B12 deficiency. There were 25.5% of the disabled vs. 11.8% of the caregivers found to have levels of vitamin B12 lower than 157 pg/ml. It is concluded that persons with ID in this vegetarian residential care community seemed to be at a higher risk for vitamin B12 deficiency.

  6. Magnetic properties of Ho1- x Lu x B12 solid solutions

    Science.gov (United States)

    Gabáni, S.; Gaz̆o, E.; Pristás̆, G.; Takác̆ová, I.; Flachbart, K.; Shitsevalova, N.; Siemensmeyer, K.; Sluchanko, N.

    2013-05-01

    Magnetic properties of the geometrically frustrated antiferromagnet HoB12 (with T N = 7.4 K) modified by substitution of magnetic Ho atoms through non-magnetic Lu ones are presented and discussed. In this case, in Ho1- x Lu x B12 solid solutions, both chemical pressure resulting from different Lu3+ and Ho3+ radii and magnetic dilution take place with increasing Lu content ( x) that change properties of the system. The received results show strong indication for the existence of a quantum critical point near x = 0.9, which separates the region of magnetic order (starting with HoB12 for x = 0) and the nonmagnetic region (ending with superconducting LuB12 for x = 1).

  7. 维生素B12的保健作用

    Institute of Scientific and Technical Information of China (English)

    王华

    2012-01-01

    一、维生素B12的生理功能1提高叶酸利用率维生素B12与叶酸一起合成甲硫氨酸(由高半胱氨酸合成)和胆碱,在产生嘌呤和嘧啶的过程中合成甲基钴胺和辅酶B12,参与许多重要化合物的甲基化过程.维生素B12缺乏时,使叶酸变成不能利用的形式,导致叶酸缺乏症.

  8. 辅酶B12及其模型化合物

    Institute of Scientific and Technical Information of China (English)

    陈慧兰

    1989-01-01

    辅酶B12,即5’-脱氧腺苷钴胺素,是一个天然存在的有机金属化合物。它与维生素B12,即氰钴胺素组成和结构相似,但生理功能不同,维生素B12是一种抗恶性贫血的药物,而辅酶B12在生物体内多种代谢过程中起着重要作用,其中研究得最多的是与分子内重排有关的酶反

  9. 维生素B12与老年痴呆

    Institute of Scientific and Technical Information of China (English)

    严段梅(译)

    2006-01-01

    美国营养学掌调查了马萨诸塞州一家族的后裔,从26岁到83岁的男女共5000人的难生素B12血浆冰平。结果表明,39%的人体内B12水平居于正常偏低,近25%的人维生素B12水平处于不足状态。研究者认为,在一般人中还有很多维生素B12缺乏的患者未被发现。

  10. 维生素B12与二甲双胍

    Institute of Scientific and Technical Information of China (English)

    汪经平

    2010-01-01

    @@ 二甲双胍是治疗2型糖尿病最常用的一线药物.根据新英格兰杂志的最新研究:2型糖尿病患者长期使用二甲双胍会增加维生素B12缺乏的风险,换句话说,维生素B12随着用药时间较长而流失.众所周知,二甲双胍能引起维生素B12缺乏,这与叶酸浓度降低有关,最终导致同型半胱氨酸的水平升高,这是维生素B12和叶酸缺乏的标记.

  11. 素食者及老人应补充维生素B12

    Institute of Scientific and Technical Information of China (English)

    马因

    2005-01-01

    维生素B12对维持健康的神经细胞和血红细胞至关重要,缺乏维生素B12会导致很多疾病,轻者出现疲劳和轻微头晕,重则神经受损、贫血和痴呆。目前维生素B12缺乏现象比医生认为的更普遍,而那些最容易缺乏维生素B12的人群是素食者及老人们。

  12. Masking of vitamin B12 deficiency associated neuropathy by folic acid

    NARCIS (Netherlands)

    van Amsterdam JGC; Opperhuizen A; Jansen EHJM; TOX

    2005-01-01

    Het Ministerie van VWS overweegt om bepaalde voedselbestanddelen te verrijken met foliumzuur. Foliumzuurverrijking houdt echter een gezondheidsrisico in, omdat het vitamine B12 deficientie maskeert, waardoor het de incidentie van megaloblastische anemie en perifere neuropathie kan verhogen. Dit ra

  13. [Folate metabolism--epigenetic role of choline and vitamin B12 during pregnancy].

    Science.gov (United States)

    Drews, Krzysztof

    2015-12-01

    Adequate choline intake during pregnancy is essential for proper fetal development. Nowadays studies suggest that even in high income countries regular pregnant women diet does not provide the satisfactory amount of choline. Choline demand during pregnancy is high and it seems to exceed present choline intake recommendations. Moreover lactation period also demands choline supplementation because of its high concentration in female milk. Numerous studies on animal model proved correlation between choline supplementation during pregnancy and proper fetal cognitive function development. Despite increased synthesis in maternal liver during pregnancy choline demand is much higher than common dietary uptake. Nowadays studies as to the nutritional recommendations during pregnancy concern also vitamin B12 supplementation. Vitamin B12 deficiency may be an important risk factor of neural tube defects development. Presented article contains a review of data on proper choline and vitamin B12 uptake during pregnancy and lactation and potential results of choline and vitamin B12 poor maternal status.

  14. Genetic architecture of vitamin B12 and folate levels uncovered applying deeply sequenced large datasets

    DEFF Research Database (Denmark)

    Grarup, Niels; Sulem, Patrick; Sandholt, Camilla H

    2013-01-01

    of the underlying biology of human traits and diseases. Here, we used a large Icelandic whole genome sequence dataset combined with Danish exome sequence data to gain insight into the genetic architecture of serum levels of vitamin B12 (B12) and folate. Up to 22.9 million sequence variants were analyzed in combined...... analyses established that four loci contain additional independent signals. Interestingly, 13 of the 18 identified variants were coding and 11 of the 13 target genes have known functions related to B12 and folate pathways. Contrary to epidemiological studies we did not find consistent association...... in serum B12 or folate levels do not modify the risk of developing these conditions. Yet, the study demonstrates the value of combining whole genome and exome sequencing approaches to ascertain the genetic and molecular architectures underlying quantitative trait associations....

  15. Rapid determination of vitamin B2 and B12 in human urine by isocratic liquid chromatography.

    Science.gov (United States)

    Mandal, Santi M; Mandal, Mahitosh; Ghosh, Ananta K; Dey, Satyahari

    2009-04-27

    A simple and rapid method for the identification and quantification of vitamin B(2) and B(12) in human urine has been developed using reverse phase high performance liquid chromatography (HPLC) and the peaks identity were confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). HPLC separation was performed in single wavelength detector (lambda(365)) mode and separated isocratically using mobile phase methanol: 1mM aqueous TFA (1:4) in C18 column. The calibration graphs plotted with different concentrations of vitamin B(2) and B(12) was linear with a correlation coefficients (r(2))=0.9975 and 0.9985, respectively. The recoveries of vitamin B(2) and B(12) were above 87% and 90%, respectively. The results of this present study suggest that the proposed method may be simple and convenient way of identifying and quantifying vitamin B(2) and B(12) from human urine.

  16. Low vitamin B-12 status and risk of cognitive decline in older adults

    DEFF Research Database (Denmark)

    Clarke, Robert; Birks, Jacqueline; Nexo, Ebba

    2007-01-01

    BACKGROUND: Elevated total homocysteine (tHcy) concentrations have been associated with cognitive impairment, but it is unclear whether low vitamin B-12 or folate status is responsible for cognitive decline. OBJECTIVE: We examined the associations of cognitive decline with vitamin B-12 and folate...... status in a longitudinal cohort study performed from 1993 to 2003 in Oxford, United Kingdom. DESIGN: Cognitive function was assessed with the Mini-Mental State Examination on >/=3 occasions during 10 y and related to serum concentrations of vitamin B-12, holotranscobalamin (holoTC), tHcy, methylmalonic...... for established risk factors, concentrations of holoTC (a marker of reduced vitamin B-12 status), tHcy, and MMA predicted cognitive decline, but folate did not. A doubling in holoTC concentrations (from 50 to 100 pmol/L) was associated with a 30% slower rate of cognitive decline (-0.137 to -0.083), whereas...

  17. Relation between serum vitamin B12 level and duration of treatment with carbamazepine in epilepsy patients

    Directory of Open Access Journals (Sweden)

    Mohammad Tariqul Islam

    2016-12-01

    Full Text Available Vitamin B12 levels in the serum of 58 epileptic patients receiving only carbamazepine for at least 6 months were measured. Same number of epilepsy patients with no history of taking antiepileptic medicine were taken as control. The mean level of vitamin B12 in carbamazepine-treated epileptic patients was 265.5 pg/mL whereas it was 478.3 pg/mL in control. Increased duration of treatment of carbamazepine in epilepsy caused significantly decreased level of serum vitamin B12 (Pearson correlation coefficient, r = -0.9, p<0.0001. In conclusion, serum vitamin B12 level significantly decreased in relation to duration of carbamazepine treatment in epileptic patients.

  18. A new role for glutathione: protection of vitamin B12 from depletion by xenobiotics.

    Science.gov (United States)

    Watson, William P; Munter, Tony; Golding, Bernard T

    2004-12-01

    NADPH in microsomes reduces the hydroxocob(III)alamin form of vitamin B12 to cob(II)alamin and the supernucleophilic cob(I)alamin, which are both highly reactive toward xenobiotic epoxides formed by mammalian metabolism of dienes such as the industrially important chemicals chloroprene and 1,3-butadiene. With styrene, the metabolically formed styrene oxide is reactive toward cob(I)alamin but not cob(II)alamin. Such reactions in humans could lead to vitamin B12 deficiency, which is implicated in pernicious anemia, cancer, and degenerative diseases. However, glutathione inhibits the reduction of hydroxocob(III)alamin by formation of the 1:1 complex glutathionylcobalamin. This blocks reactions of the cobalamins with metabolically formed epoxides. The interaction between glutathione and vitamin B12 could protect against diseases related to vitamin B12 depletion.

  19. New derivatives of vitamin B12 show preferential targeting of tumors.

    Science.gov (United States)

    Waibel, Robert; Treichler, Hansjörg; Schaefer, Niklaus G; van Staveren, Dave R; Mundwiler, Stefan; Kunze, Susanne; Küenzi, Martin; Alberto, Roger; Nüesch, Jakob; Knuth, Alexander; Moch, Holger; Schibli, Roger; Schubiger, Pius August

    2008-04-15

    Rapidly growing cells show an increased demand for nutrients and vitamins. The objective of our work is to exploit the supply route of vitamin B12 to deliver new derivatives of this vital vitamin to hyperproliferative cells. To date, radiolabeled ((57)Co and (111)In) vitamin B12 derivatives showed labeling of tumor tissue but also undesired high accumulation of radioactivity in normal tissue. By abolishing the interaction of a tailored vitamin B12 derivative to its transport protein transcobalamin II and therefore interrupting transcobalamin II receptor and megalin mediated uptake in normal tissue, preferential accumulation of a radiolabeled vitamin in cancer tissue could be accomplished. We identified transcobalamin I on tumors as a possible new receptor for this preferential accumulation of vitamin-mediated targeting. The low systemic distribution of radioactivity and the high tumor to blood ratio opens the possibility of a more successful clinical application of vitamin B12 for imaging or therapy.

  20. Probabilistic modeling of percutaneous absorption for risk-based exposure assessments and transdermal drug delivery.

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Clifford Kuofei

    2004-06-01

    Chemical transport through human skin can play a significant role in human exposure to toxic chemicals in the workplace, as well as to chemical/biological warfare agents in the battlefield. The viability of transdermal drug delivery also relies on chemical transport processes through the skin. Models of percutaneous absorption are needed for risk-based exposure assessments and drug-delivery analyses, but previous mechanistic models have been largely deterministic. A probabilistic, transient, three-phase model of percutaneous absorption of chemicals has been developed to assess the relative importance of uncertain parameters and processes that may be important to risk-based assessments. Penetration routes through the skin that were modeled include the following: (1) intercellular diffusion through the multiphase stratum corneum; (2) aqueous-phase diffusion through sweat ducts; and (3) oil-phase diffusion through hair follicles. Uncertainty distributions were developed for the model parameters, and a Monte Carlo analysis was performed to simulate probability distributions of mass fluxes through each of the routes. Sensitivity analyses using stepwise linear regression were also performed to identify model parameters that were most important to the simulated mass fluxes at different times. This probabilistic analysis of percutaneous absorption (PAPA) method has been developed to improve risk-based exposure assessments and transdermal drug-delivery analyses, where parameters and processes can be highly uncertain.

  1. A mechanism-based approach for absorption modeling: the Gastro-Intestinal Transit Time (GITT) model.

    Science.gov (United States)

    Hénin, Emilie; Bergstrand, Martin; Standing, Joseph F; Karlsson, Mats O

    2012-06-01

    Absorption models used in the estimation of pharmacokinetic drug characteristics from plasma concentration data are generally empirical and simple, utilizing no prior information on gastro-intestinal (GI) transit patterns. Our aim was to develop and evaluate an estimation strategy based on a mechanism-based model for drug absorption, which takes into account the tablet movement through the GI transit. This work is an extension of a previous model utilizing tablet movement characteristics derived from magnetic marker monitoring (MMM) and pharmacokinetic data. The new approach, which replaces MMM data with a GI transit model, was evaluated in data sets where MMM data were available (felodipine) or not available (diclofenac). Pharmacokinetic profiles in both datasets were well described by the model according to goodness-of-fit plots. Visual predictive checks showed the model to give superior simulation properties compared with a standard empirical approach (first-order absorption rate + lag-time). This model represents a step towards an integrated mechanism-based NLME model, where the use of physiological knowledge and in vitro–in vivo correlation helps fully characterize PK and generate hypotheses for new formulations or specific populations.

  2. A case of anemia caused by combined vitamin B12 and iron deficiency manifesting as short stature and delayed puberty Anemia

    Directory of Open Access Journals (Sweden)

    Seung Min Song

    2010-05-01

    Full Text Available Anemia caused by vitamin B12 deficiency resulting from inadequate dietary intake is rare in children in the modern era because of improvements in nutritional status. However, such anemia can be caused by decreased ingestion or impaired absorption and/ or utilization of vitamin B12. We report the case of an 18-year-old man with short stature, prepubertal sexual maturation, exertional dyspnea, and severe anemia with a hemoglobin level of 3.3 g/dL. He had a history of small bowel resection from 50 cm below the Treitz ligament to 5 cm above the ileocecal valve necessitated by midgut volvulus in the neonatal period. Laboratory tests showed deficiencies of both vitamin B12 and iron. A bone marrow examination revealed dyserythropoiesis and low levels of hemosiderin particles, and a cytogenetic study disclosed a normal karyotype. After treatment with parenteral vitamin B12 and elemental iron, both anemia and growth showed gradual improvement. This is a rare case that presented with short stature and delayed puberty caused by nutritional deficiency anemia in Korea.

  3. AB156. Homocysteine and vitamin B12: risk factors for erectile dysfunction

    Science.gov (United States)

    Lu, Zheng; Mo, Zengnan

    2014-01-01

    Background Increasing levels of homocysteine (Hcy) is associated with cardiovascular disease, and erectile dysfunction (ED) has close relation with cardiovascular disease, therefore, high homocysteine may be one of the risk factors of ED. During the metabolism of homocysteine, vitamin B12 plays an important role and could be the main factor in causing erectile dysfunction as well. Purpose To investigate the relationship between Hcy, vitamin B12 and ED in sample. Methods The study included 1,457 men aged 20-69 who participated in a series of physical examination at the Medical Centre in Fangchenggang First People’s Hospital from September 2009 to December 2009. ED was identified by the five-item International Index of Erectile Function (IIEF-5) questionnaire. All participants were measured for plasma Hcy, vitamin B12, folic acid, systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), fasting plasma glucose, triglyceride and high-density lipoprotein cholesterol (HDL). Smoking, alcoholic drinking and physical activity were collected by face to face communication. Results A total of 691 (47.4%) men were identified as ED in this study, participants with ED were older or more likely to drink alcohol than the non-ED. It was higher Hcy (P=0.032), vitamin B12 (P=0.008) and fasting plasma glucose (P=0.014) in the participants with ED. There were significant positive correlation between ED status (none, mile, moderate and severe) and Hcy (P=0.024), vitamin B12 (P=0.015) and fasting plasma glucose (P=0.002). Logistic regression analysis showed that age, Hcy and vitamin B12 were the main determinants in ED. Hcy was positively associated with ED in the men more than 45, but vitamin B12 was positively related with ED in the men less than 45. Conclusions Hcy was positively associated with ED in elder, however, vitamin B12 was positively related with ED in younger.

  4. Charles Bonnet syndrome and vitamin B12 deficiency: a case report.

    Science.gov (United States)

    Bourgeois, Valérie; Desbordes, Marie; Follet, Mathieu; Haouzir, Sadeq; Guillin, Olivier

    2010-01-01

    The Charles Bonnet syndrome (CBS) is a condition associated with complex visual hallucinations occurring in the elderly in patients with visual impairment and normal mental health. Here, we report the case of a 78-year-old woman who has a limited visual acuity with a CBS that we postulated to be in relationship to a vitamin B12 deficiency. This case is the first report of vitamin B12 deficiency-associated CBS.

  5. Signs and Symptoms of Vitamin B12 Deficiency and its Impacts on Student's Academic Performance

    OpenAIRE

    Mustafa Mohammed Mustafa; Abdulrahman A. Al Atram; Mahmoud M. Mousleh

    2014-01-01

    This study carried out to determine the impact of vitamin B12 deficiency signs and symptoms , on the academic achievement of student’s in Majmah University. well designed questionnaire by Dr Lisa Watson (Doctor of Naturopathic Medicine) vitamin B12 deficiency signs and symptoms was used and filled out for each student, which included information on demographical factors as: sex, age, work. A convenient sample consisted of (298) students (238, 60) male and female respectively, from (11) fac...

  6. Response to Vitamin B12 and Folic Acid in Myalgic Encephalomyelitis and Fibromyalgia

    OpenAIRE

    Björn Regland; Sara Forsmark; Lena Halaouate; Michael Matousek; Birgitta Peilot; Olof Zachrisson; Carl-Gerhard Gottfries

    2015-01-01

    Background Patients with myalgic encephalomyelitis (ME, also called chronic fatigue syndrome) may respond most favorably to frequent vitamin B12 injections, in vital combination with oral folic acid. However, there is no established algorithm for individualized optimal dosages, and rate of improvement may differ considerably between responders. Objective To evaluate clinical data from patients with ME, with or without fibromyalgia, who had been on B12 injections at least once a week for six m...

  7. Vitamin B12 modulates the transcriptome of the skin microbiota in acne pathogenesis.

    Science.gov (United States)

    Kang, Dezhi; Shi, Baochen; Erfe, Marie C; Craft, Noah; Li, Huiying

    2015-06-24

    Various diseases have been linked to the human microbiota, but the underlying molecular mechanisms of the microbiota in disease pathogenesis are often poorly understood. Using acne as a disease model, we aimed to understand the molecular response of the skin microbiota to host metabolite signaling in disease pathogenesis. Metatranscriptomic analysis revealed that the transcriptional profiles of the skin microbiota separated acne patients from healthy individuals. The vitamin B12 biosynthesis pathway in the skin bacterium Propionibacterium acnes was significantly down-regulated in acne patients. We hypothesized that host vitamin B12 modulates the activities of the skin microbiota and contributes to acne pathogenesis. To test this hypothesis, we analyzed the skin microbiota in healthy subjects supplemented with vitamin B12. We found that the supplementation repressed the expression of vitamin B12 biosynthesis genes in P. acnes and altered the transcriptome of the skin microbiota. One of the 10 subjects studied developed acne 1 week after vitamin B12 supplementation. To further understand the molecular mechanism, we revealed that vitamin B12 supplementation in P. acnes cultures promoted the production of porphyrins, which have been shown to induce inflammation in acne. Our findings suggest a new bacterial pathogenesis pathway in acne and provide one molecular explanation for the long-standing clinical observation that vitamin B12 supplementation leads to acne development in a subset of individuals. Our study discovered that vitamin B12, an essential nutrient in humans, modulates the transcriptional activities of skin bacteria, and provided evidence that metabolite-mediated interactions between the host and the skin microbiota play essential roles in disease development.

  8. Incidence of vitamin B12 / D3 deficiency among company executives

    Directory of Open Access Journals (Sweden)

    Gulvady Chaitanya

    2007-01-01

    Full Text Available The present cross-sectional and interventional study was carried out to assess the incidence of vitamin B12 / vitamin D deficiency in male office executives in the tropical city of Mumbai, India. A total of 75 senior executives were surveyed and subjected to analysis of blood levels of vitamin D (25 Hydroxy Cholecalciferol by RIA method and vitamin B12 by CLIA method. The same was performed in a reputed analytical laboratory with NABL accreditation. History of smoking, exposure to sunlight, exercise, dietary habits, consumption of vitamin supplements, medication etc. was obtained. The results revealed 65% executives with vitamin B12 deficiency (less than 193 pg/ml and 28% executives with vitamin D deficiency (less than 7.6 ng/ml. The prevalence of low levels of vitamin B12 is lower (58% in those who give history of regular exercise than others. The prevalence of vitamin D deficiency is lower (25% in those who give history of regular exercise than in others (46.2%. Prevalence of vitamin D deficiency is higher (47% in those whose workday day started earlier than in those whose workday started later (12%. In the second phase of the survey, 58 executives with low B12/ D3 values, were given vitamin B12/D3 oral supplements for a period of three months along with counseling for lifestyle modification. A modified questionnaire was then circulated and the subjects analyzed for B12/D3 values. Significant improvements in serum B12 and D3 values were seen after the oral therapy, sun exposure and dietary modifications.

  9. The level of Vitamin B12 and hemoglobin in patients with recurrent aphthous stomatitis

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    Kamran Sari

    2016-01-01

    Full Text Available Background: Recurrent aphthous stomatitis (RAS is a chronic inflammatory disease of the oral cavity. Although many factors have been suggested as possible causes of RAS, its precise etiology is controversial. Vitamin B12 (vit B12 and iron deficiencies may cause RAS. Aims: We investigated the level of serum hemoglobin (Hb and vit B12 in patients with RAS and to compare them with healthy controls. Materials and Methods: This was a prospective, cross-sectional study. Patients who had had at least one episode of oral ulcerations per month since childhood were diagnosed as having RAS. Blood samples were drawn from the RAS group and control group for measuring blood Hb and vit B12 concentrations. Results: Exactly 195 patients (62 men and 133 women with RAS and 217 healthy controls (62 men and 155 women were enrolled in the study. The RAS group had significantly lower mean Hb levels than the control group (P < 0.001. No significant difference in the mean vit B12 level was demonstrated between the study group and controls. Around 58 (29.7% patients were diagnosed as Hb deficient in the RAS group and 21 (9.7% patients in controls. Vit B12 deficiency was diagnosed in 63 (32.3% individuals in the RAS group and 32 (14.7% individuals among controls. Conclusions: In our study, vit B12 and Hb deficiency were found higher in patients with RAS compared to the control group. Therefore, we suggested the investigation of the level of vit B12 and Hb in patients with RAS.

  10. Vitamin B12 deficiency is associated with geographical latitude and solar radiation in the older population.

    Science.gov (United States)

    Cabrera, Sebastián; Benavente, David; Alvo, Miriam; de Pablo, Paola; Ferro, Charles J

    2014-11-01

    Vitamin B12 and folic acid deficiency are common in the older and are associated with several conditions including anaemia, cardiovascular disease, cognitive impairment and cancer. Evidence from in vitro studies suggests that solar radiation can degrade both vitamins in the skin. Chile is the longest country in the world running perfectly North-South making it an ideal place to study potential associations of latitude and solar radiation on vitamin B12 and folic acid deficiency. The objective was to examine the association between vitamin B12 and folic acid deficiencies and latitude. Plasma samples were collected from Chileans aged 65+ years (n=1013) living across the whole country and assayed for vitamin B12 and folic acid concentrations as part of the Chilean Health Survey 2009-2010, which is a national representative sample study. Overall, the prevalence of vitamin B12 deficiency was 11.3%, with the prevalence in the North of the country being significantly greater than in the Central and South zones (19.1%,10.5%, and 5.7%, respectively; Pvitamin B12 deficiency was significantly associated with geographical latitude (OR 0.910 [95% confidence intervals 0.890-0.940], Pvitamin B12 deficiency is associated with living closer to the Equator and solar radiation. Although degradation by solar radiation might explain this observation, further work is required to establish the potential mechanisms. In countries that routinely fortify food with folic acid, efforts to identify vitamin B12 deficiency might be more cost-efficiently targeted in areas closest to the Equator. Copyright © 2014 Elsevier B.V. All rights reserved.

  11. Microbial production of vitamin B12: a review and future perspectives.

    Science.gov (United States)

    Fang, Huan; Kang, Jie; Zhang, Dawei

    2017-01-30

    Vitamin B12 is an essential vitamin that is widely used in medical and food industries. Vitamin B12 biosynthesis is confined to few bacteria and archaea, and as such its production relies on microbial fermentation. Rational strain engineering is dependent on efficient genetic tools and a detailed knowledge of metabolic pathways, regulation of which can be applied to improve product yield. Recent advances in synthetic biology and metabolic engineering have been used to efficiently construct many microbial chemical factories. Many published reviews have probed the vitamin B12 biosynthetic pathway. To maximize the potential of microbes for vitamin B12 production, new strategies and tools are required. In this review, we provide a comprehensive understanding of advances in the microbial production of vitamin B12, with a particular focus on establishing a heterologous host for the vitamin B12 production, as well as on strategies and tools that have been applied to increase microbial cobalamin production. Several worthy strategies employed for other products are also included.

  12. [Vitamin B12 supplementation and milk production on farms with 'chronic wasting' cattle].

    Science.gov (United States)

    Weber, M F; Verhoeff, J; Holzhauer, M; Bartels, C J; van Wuijckhuise, L; Vellema, P

    2001-03-15

    From early 1999 onwards, cattle health problems accompanied by chronic wasting of unknown aetiology were reported on a number of dairy farms. An association between these health problems and the compulsory use of gE-negative marker vaccines against bovine herpesvirus 1 was presumed by farmers. On one dairy farm an increased milk production of 50% was reported within a few days after parenteral vitamin B12 treatment. Therefore, the current study was designed to determine the effect of parenteral vitamin B12 treatment on the milk production of dairy herds with wasting cattle. A randomized blind trial was performed in five problem herds and two control herds. On each farm five lactating cows were injected intramuscularly with 20 mg vitamin B12 and paired with five untreated lactating cows. The milk production of treated and untreated animals was measured for 19 days following treatment and compared to pre-treatment production. No effect of vitamin B12 treatment on milk production was established on either problem farms or control farms. Neither was a difference detected in the response to vitamin B12 treatment between problem herds and control herds. In a second experiment, parenteral vitamin B12 treatment was applied in three problem herds by local veterinary practitioners. The results of this experiment were in line with the results of the first experiment.

  13. Competitive chemiluminescent enzyme immunoassay for vitamin B12 analysis in human milk.

    Science.gov (United States)

    Hampel, Daniela; Shahab-Ferdows, Setareh; Domek, Joseph M; Siddiqua, Towfida; Raqib, Rubhana; Allen, Lindsay H

    2014-06-15

    Recent discoveries of matrix interferences by haptocorrin (HC) in human milk and serum show that past analyses of vitamin B12 in samples with high HC content might have been inaccurate (Lildballe et al., 2009; Carmel & Agrawal, 2012). We evaluated two competitive enzyme-binding immunoassays for serum/plasma (IMMULITE and SimulTRAC-SNB) for B12 analysis in human milk. B12-recovery rates (United States Environmental Protection Agency, 2007) were determined to be 78.9 ± 9.1% with IMMULITE and 225 ± 108% (range 116-553%) using SimulTRAC-SNB, most likely due to the presence of excess HC. HC-interferences were not observed with the IMMULITE assay, rendering previously reported mandatory HC-removal (Lildballe et al., 2009) unnecessary. Linearity continued at low B12-concentrations (24-193 pM; r(2)>0.985). Milk B12 concentrations from Bangladeshi women (72-959 pM) were significantly lower than those from California (154-933 pM; pmilk matrix and its ability to measure low milk B12 concentrations.

  14. Vitamin B12 and folate deficiency: should we use a different cutoff value for hematologic disorders?

    Science.gov (United States)

    Toprak, B; Yalcın, H Z; Colak, A

    2014-08-01

    Anemia and macrocytosis are well-defined expected hematologic findings of vitamin B12 and folate deficiency; however, some previous studies did not show a significant association of subnormal B12 with anemia and macrocytosis. We retrospectively analyzed 17 713 laboratory patient records to evaluate vitamin B12 and folate levels in relation to anemia and macrocytosis. In an age- and sex-adjusted logistic regression model, low B12 status but not marginal B12 status was significantly associated with anemia [ORs respectively, 1.291 (95% CI, 1.182-1.410), 1.022 (95% CI, 0.943-1.108)] and macrocytosis [ORs, respectively, 3.853 (95% CI, 3.121-4.756), 1.031 (95% CI, 0.770-1.381)]. Also low folate status but not marginal folate status was significantly associated with anemia [adjusted ORs, respectively, 1.819 (95% CI, 1.372-2.411), 1.101 (95% CI, 0.931-1.301)] and macrocytosis [adjusted ORs, respectively, 2.945 (95% CI, 1.747-4.965), 1.228 (95% CI, 0.795-1.898)]. Our results show that increased anemia and macrocytosis are observed at values below commonly used B12 lower-reference thresholds. Determining a hematologic cutoff value may help physicians in clinical practice. © 2013 John Wiley & Sons Ltd.

  15. Vitamin B12: one carbon metabolism, fetal growth and programming for chronic disease.

    Science.gov (United States)

    Rush, E C; Katre, P; Yajnik, C S

    2014-01-01

    This review brings together human and animal studies and reviews that examine the possible role of maternal vitamin B12 (B12) on fetal growth and its programming for susceptibility to chronic disease. A selective literature review was undertaken to identify studies and reviews that investigate these issues, particularly in the context of a vegetarian diet that may be low in B12 and protein and high in carbohydrate. Evidence is accumulating that maternal B12 status influences fetal growth and development. Low maternal vitamin B12 status and protein intake are associated with increased risk of neural tube defect, low lean mass and excess adiposity, increased insulin resistance, impaired neurodevelopment and altered risk of cancer in the offspring. Vitamin B12 is a key nutrient associated with one carbon metabolic pathways related to substrate metabolism, synthesis and stability of nucleic acids and methylation of DNA which regulates gene expression. Understanding of factors regulating maternal-fetal one carbon metabolism and its role in fetal programming of non communicable diseases could help design effective interventions, starting with maternal nutrition before conception.

  16. Associations between Vitamin B-12 Status and Oxidative Stress and Inflammation in Diabetic Vegetarians and Omnivores.

    Science.gov (United States)

    Lee, Yau-Jiunn; Wang, Ming-Yang; Lin, Mon-Chiou; Lin, Ping-Ting

    2016-02-26

    Diabetes is considered an oxidative stress and a chronic inflammatory disease. The purpose of this study was to investigate the correlations between vitamin B-12 status and oxidative stress and inflammation in diabetic vegetarians and omnivores. We enrolled 154 patients with type 2 diabetes (54 vegetarians and 100 omnivores). Levels of fasting glucose, glycohemoglobin (HbA1c), lipid profiles, oxidative stress, antioxidant enzymes activity, and inflammatory makers were measured. Diabetic vegetarians with higher levels of vitamin B-12 (>250 pmol/L) had significantly lower levels of fasting glucose, HbA1c and higher antioxidant enzyme activity (catalase) than those with lower levels of vitamin B-12 (≤ 250 pmol/L). A significant association was found between vitamin B-12 status and fasting glucose (r = -0.17, p = 0.03), HbA1c (r = -0.33, p = 0.02), oxidative stress (oxidized low density lipoprotein-cholesterol, r = -0.19, p = 0.03), and antioxidant enzyme activity (catalase, r = 0.28, p = 0.01) in the diabetic vegetarians; vitamin B-12 status was significantly correlated with inflammatory markers (interleukin-6, r = -0.33, p diabetic omnivores. As a result, we suggest that it is necessary to monitor the levels of vitamin B-12 in patients with diabetes, particularly those adhering to a vegetarian diet.

  17. The evaluation of serum homocysteine, folic acid, and vitamin B12 in patients complicated with preeclampsia.

    Science.gov (United States)

    Shahbazian, Nahid; Jafari, Razieh Mohammad; Haghnia, Sahar

    2016-10-01

    Increased plasma homocysteine may be associated with adverse pregnancy outcomes, such as preeclampsia. The aim of this study was to determine the plasma homocysteine, serum folate, and vitamin B12 levels in preeclamptic pregnant women. This case-control study was conducted in 2016 in Ahwaz on 51 pregnant women with preeclampsia and 51 healthy pregnant women of the same gestational age, who served as controls. The case group also was subdivided into severe and non-severe preeclampsia. Patients' data were collected through a questionnaire and medical records. Serum homocysteine, folic acid, and vitamin B12 were analyzed using chemiluminescent assay. The results were compared between two groups. Statistical analyses were done using IBM-SPSS 20.0. A Kolmogorov-Smirnov test, independent samples t-test, Mann-Whitney test, and Chi-square test were used for data analysis. No different demographic characteristics were found among the groups. Pregnant women complicated with preeclampsia displayed significantly higher serum homocysteine levels (p vitamin B12 levels (p vitamin B12, but it was not statistically significant (p = 0.160; r = -0.200). Significant differences occurred in serum homocysteine and folate levels between the severe and non-severe subgroups (p vitamin B12. Further studies are needed to confirm if the prescription of folic acid and vitamin B12 in women with a deficiency of these vitamins could decrease the level of serum homocysteine and, therefore, reduce the risk of preeclampsia or, if it occurred, its severity.

  18. B12 Vitamin and Folat Prevelance of Children and Adolescents in Diyarbakır

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    Kahraman Öncel

    2006-01-01

    Full Text Available The most common cause of megaloblastic anemia in childhood are vitamin B12 and folat deficiency. Folat and vitamin B12 play a role in DNA synthessis in gastrointestinal, urogenital,nerves and hemotopoetic cells. The diagnosis of megaloblastic anemia is easy and the treatment cost is low.In this study, the prevalence of vitamin B12 and folat deficiencies in 889 students were determined. Vitamin B12 and folat levels in blood samples were measured via RİAThe average age were betwen 12 and 22 years. Of this students 294(%33,1 were female and 595 (%66,9 were male. The incidence of vitamin B12 deficiency was found to be 2.2%, while folat deficiency was 21.8%. The mean vitamin B12 level was 331,51±144,05 pg/mL (325,60±138,91 in pg/mL male, 343,48±153,48 pg/mL in female, the mean folat level was 5,42±2,12 ng/ml (5,23±2,11 ng/ml in male, 5,80±2,10 ng/ml in female.The prevelance of folat deficiency in our region was higher than other countries, possibly due to low socioeconomical status, improper or inadequate food intake and low educational status.

  19. Holotranscobalamin Is a Useful Marker of Vitamin B12 Deficiency in Alcoholics

    Directory of Open Access Journals (Sweden)

    Alberto Fragasso

    2012-01-01

    Full Text Available Background. Measurement of serum cobalamin (Cbl levels is the standard investigation for assessing vitamin B12 deficiency. Falsely increased values of Cbl can be caused by alcoholic liver disease. Measurement of total vitamin B12 serum levels might be misleading in alcoholics, because a tissue metabolic deficiency is possible even with normal serum Cbl levels. Holotranscobalamin (HoloTC, the Cbl metabolically active fraction, is considered as a better index of vitamin B12 deficiency. Methods. For assessing vitamin B12 status, we evaluated 22 adult alcoholic male patients by measuring in parallel serum Cbl, serum folate and red blood cell folate levels, HoloTC levels by the AxSYM assay. Results. HoloTC values were reduced in 3 alcoholics with borderline-low Cbl values. Significant positive correlations were found between serum Cbl and HoloTC levels, serum Cbl and gamma-glutamyl transpeptidase (GGT. Conclusion. HoloTC measurement is a useful option for assessing vitamin B12 status in alcoholics, particularly in the subjects with borderline Cbl values and may be considered an early marker of vitamin B12 deficiency.

  20. Vitamin B12 status in women of childbearing age in the UK and its relationship with national nutrient intake guidelines: results from two National Diet and Nutrition Surveys

    Science.gov (United States)

    Adaikalakoteswari, Antonysunil; Venkataraman, Hema; Maheswaran, Hendramoorthy; Saravanan, Ponnusamy

    2016-01-01

    Objective To assess serum B12, folate and the associated homocysteine (Hcy) levels among women of childbearing age in the UK and examine their association with dietary intake in relation to the UK Recommended Nutrient Intakes (RNIs) for B12 and folate. Design Cross-sectional study. Setting Data from two publicly available National Diet and Nutrition Surveys (NDNS 2000/2001 and 2008/2012) were used. These were population-based surveys of randomly selected samples of adults which were carried out in their households. Participants Women of childbearing age (aged 19–39 years), representative of the UK population. Those who were pregnant or breastfeeding were excluded. Outcome measures The associations between micronutrient intakes and blood levels of B12, folate and Hcy were assessed by correlation and stepwise linear regression. B12 intake was divided into quintiles and plotted against blood B12 and Hcy concentrations to determine the threshold of any associations. Results 299 women from the first NDNS cohort had complete intake and biomarker data. The prevalence of serum vitamin B12 (≤150 pmol/L) and serum folate (≤10 nmol/L) deficiency and hyperhomocysteinemia (≥12 µmol/L) was 12.4%, 6.4% and 21.2%, respectively, despite seemingly adequate B12 intakes (median 3.8 μg/day, 96% consumed more than the UK RNI of 1.5 μg/day). B12 concentrations increased across all quintiles of intake with serum levels in quintiles 4 and 5 (median intake 4.9 and 7.1 μg/day, respectively) significantly higher than quintile 1. However, Hcy concentrations levelled off between quintiles 4 and 5. Comparison of micronutrient intake between the two surveys found that folate intake has reduced in the more recent cohort. Conclusions The UK RNI for B12 intake should be increased for women of childbearing age with intakes of around 5–7 μg/day likely to be associated with stable biomarker levels. B12 levels should also be measured in women preconceptionally or in early

  1. Structural color printing based on plasmonic metasurfaces of perfect light absorption

    Science.gov (United States)

    Cheng, Fei; Gao, Jie; Luk, Ting S.; Yang, Xiaodong

    2015-06-01

    Subwavelength structural color filtering and printing technologies employing plasmonic nanostructures have recently been recognized as an important and beneficial complement to the traditional colorant-based pigmentation. However, the color saturation, brightness and incident angle tolerance of structural color printing need to be improved to meet the application requirement. Here we demonstrate a structural color printing method based on plasmonic metasurfaces of perfect light absorption to improve color performances such as saturation and brightness. Thin-layer perfect absorbers with periodic hole arrays are designed at visible frequencies and the absorption peaks are tuned by simply adjusting the hole size and periodicity. Near perfect light absorption with high quality factors are obtained to realize high-resolution, angle-insensitive plasmonic color printing with high color saturation and brightness. Moreover, the fabricated metasurfaces can be protected with a protective coating for ambient use without degrading performances. The demonstrated structural color printing platform offers great potential for applications ranging from security marking to information storage.

  2. [The development of acetylene on-line monitoring technology based on laser absorption spectrum].

    Science.gov (United States)

    He, Ying; Zhang, Yu-jun; Kan, Rui-feng; Xia, Hui; Wang, Min; Cui, Xiao-juan; Chen, Jiu-ying; Chen, Dong; Liu, Wen-qing; Liu, Jian-guo

    2008-10-01

    As one of the materials in organic chemical industry, acetylene has been used in many aspects of chemical industry. But acetylene is a very dangerous inflammable and explosive gas, so it needs in-situ monitoring during industrial storage and production. Tunable diode laser absorption spectroscopy (TDLAS) technology has been widely used in atmospheric trace gases detection, because it has a lot of advantageous characteristics, such as high sensitivity, good selectivity, and rapid time response. The distribution characteristics of absorption lines of acetylene in near infrared band were studied, and then the system designing scheme of acetylene on-line monitoring based on near infrared tunable diode laser absorption spectroscopy technology was discussed in detail. Moreover, the system of experiment measurement was set up and the method of signal detection and the algorithm of concentration inversion were studied. In addition, the sample cell with a path length of 10 cm, and the acetylene of different known concentrations were measured. As a result, the detection limit obtained reached 1.46 cm3 x m(-3). Finally the dynamic detection experiment was carried out, and the measurement result is stable and reliable, so the design of the system is practicable through experiment analysis. On-line acetylene leakage monitoring system was developed based on the experiment, and it is suitable for giving a leakage alarm of acetylene during its storage, transportation and use.

  3. [Open-path online monitoring of ambient atmospheric CO2 based on laser absorption spectrum].

    Science.gov (United States)

    He, Ying; Zhang, Yu-Jun; Kan, Rui-Feng; Xia, Hui; Geng, Hui; Ruan, Jun; Wang, Min; Cui, Xiao-Juan; Liu, Wen-Qing

    2009-01-01

    With the conjunction of tunable diode laser absorption spectroscopy technology (TDLAS) and the open long optical path technology, the system designing scheme of CO2 on-line monitoring based on near infrared tunable diode laser absorption spectroscopy technology was discussed in detail, and the instrument for large-range measurement was set up. By choosing the infrared absorption line of CO2 at 1.57 microm whose line strength is strong and suitable for measurement, the ambient atmospheric CO2 was measured continuously with a 30 s temporal resolution at an suburb site in the autumn of 2007. The diurnal atmospheric variations of CO2 and continuous monitoring results were presented. The results show that the variation in CO2 concentration has an obvious diurnal periodicity in suburb where the air is free of interference and contamination. The general characteristic of diurnal variation is that the concentration is low in the daytime and high at night, so it matches the photosynthesis trend. The instrument can detect gas concentration online with high resolution, high sensitivity, high precision, short response time and many other advantages, the monitoring requires no gas sampling, the calibration is easy, and the detection limit is about 4.2 x 10(-7). It has been proved that the system and measurement project are feasible, so it is an effective method for gas flux continuous online monitoring of large range in ecosystem based on TDLAS technology.

  4. Dual-mode immunoassay based on shape code and infrared absorption fingerprint signals of silica nanorods.

    Science.gov (United States)

    Zhao, Pengfei; Ni, Ran; Wang, Kexin; Hong, Xia; Ding, Yadan; Cong, Tie; Liu, Junping; Zhao, Huiying

    2017-07-01

    Silica nanorods were synthesized through a simple one-pot emulsion-droplet-based growth method, in which tetraethylorthosilicate (TEOS) was used as the silica source, ammonia as the catalyst, and polyvinylpyrrolidone (PVP) as the structure-directing agent and stabilizer. By controlling hydrolysis and condensation in the reaction process, we regulated the aspect ratios and the infrared (IR) absorption fingerprint signals (the transverse optical and the longitudinal optical phonon modes) of the silica nanorods. Based on this, a dual-mode immunoassay was performed for detecting model target analyte, human IgG. The shape code of the silica nanorods was used for simple, rapid qualitative, and sensitive semi-quantitative immunoassay by using a conventional optical microscope. The characteristic IR absorption fingerprint signals of the silica nanorods allowed for reliable quantitative immunoassay with good selectivity and high specificity. The detection limit and the linear range were found out to be 0.5 pM and 1 pM-10 nM, respectively. We expect that such dual-mode immunoassay could be applied for the detection of other analytes, such as protein, nucleic acids, bacteria, viruses, explosives, toxins, and so on. Graphical abstract A simple dual-mode immunoassay was performed using the shape code and infrared absorption fingerprint signals of silica nanorods as detection signals.

  5. Tunable Absorption System based on magnetorheological elastomers and Halbach array: design and testing

    Science.gov (United States)

    Bocian, Mirosław; Kaleta, Jerzy; Lewandowski, Daniel; Przybylski, Michał

    2017-08-01

    In this paper, the systematic design, construction and testing of a Tunable Absorption System (TAS) incorporating magnetorheological elastomer (MRE) has been investigated. The TAS has been designed for energy absorption and mitigation of vibratory motions from an impact excitation. The main advantage of the designed TAS is that it has the ability to change and adapt to working conditions. Tunability can be realised through a change in the magnetic field caused by the change of an internal arrangement of permanent magnets within a double dipolar circular Halbach array. To show the capabilities of the tested system, experiments based on an impulse excitation have been performed. Significant changes of the TASs natural frequency and damping characteristics have been obtained. By incorporating magnetic tunability within the TAS a significant qualitative and quantitative change in the devices mechanical properties and performance were obtained.

  6. An absorption mechanism and polarity-induced viscosity model for CO2 capture using hydroxypyridine-based ionic liquids.

    Science.gov (United States)

    An, Xiaowei; Du, Xiao; Duan, Donghong; Shi, Lijuan; Hao, Xiaogang; Lu, Houfang; Guan, Guoqing; Peng, Changjun

    2017-01-04

    A series of new hydroxypyridine-based ionic liquids (ILs) are synthesized and applied in CO2 capture through chemical absorption, in which one IL, i.e., tetrabutylphosphonium 2-hydroxypyridine ([P4444][2-Op]), shows a viscosity as low as 193 cP with an absorption capacity as high as 1.20 mol CO2 per mol IL. Because the traditional anion-CO2 absorption mechanism cannot provide an explanation for the influences of cations and temperature on CO2 absorption capacity, herein, a novel cation-participating absorption mechanism based on the proton transfer is proposed to explain the high absorption capacity and the existence of a turning point of absorption capacity with the increase of temperature for the capture of CO2 using [P4444][n-Op] (n = 2, 3, 4) ILs. Also, the relationship between the viscosity of ILs and the linear interaction energy is proposed for the first time, which can guide how to design and synthesize ILs with low viscosity. Quantum chemistry calculations, which are based on the comprehensive analysis of dipole moment, cation-anion interaction energy and surface electrostatic potential, indicate that the different viscosities of hydroxypyridine-based ILs and the changes after CO2 absorption mainly resulted from the different distribution of negative charges in the anion.

  7. The usefulness of holotranscobalamin in predicting vitamin B12 status in different clinical settings.

    Science.gov (United States)

    Herrmann, Wolfgang; Obeid, Rima; Schorr, Heike; Geisel, Jürgen

    2005-02-01

    Serum concentrations of homocysteine (Hcy) and methylmalonic acid (MMA) become increased in B12-deficient subjects and are therefore, considered specific markers of B12 deficiency. Serum level of holotranscobalamin (holoTC) becomes decreased before the development of the metabolic dysfunction. We investigated the usefulness of holoTC in diagnosing B12 deficiency in some clinical settings. We measured serum concentrations of holoTC, MMA, Hcy and total B12 in omnivores, vegetarians, elderly people and haemodialysis patients. Our results indicated that the incidence of holoTC vegans (76%). Low holoTC and elevated MMA were detected in 64% of the vegans and 43% of the lacto- and lacto-ovovegetarians. An elevated MMA and a low holoTC were found in subjects with total serum B12 as high as 300 pmol/L. The distribution of holoTC in elderly people was similar to that in younger adults (median holoTC 55 pmol/L in both groups). A low holoTC and an elevated MMA were found in 16% of the elderly group. An elevated MMA and a normal holoTC were found in 20% of the elderly group who had a relatively high median serum concentration of creatinine (106.1 micromol/L). Serum concentrations of holoTC in dialysis patients were considerably higher than all other groups (median 100 pmol/L). This was also associated with severely increased serum levels of MMA (median 987 nmol/L). From these results it can be concluded that serum concentration of holoTC is a much better predictor of B12 status than total B12. This was particularly evident in case of dietary B12 deficiency. Serum concentrations of holoTC as well as MMA can be affected by renal dysfunction. Elevated MMA and normal holoTC in patients with renal insufficiency may not exclude vitamin B12 deficiency. HoloTC seems not to be a promising marker in predicting B12 status in renal patients.

  8. Development of a mechanistically based computer simulation of nitrogen oxide absorption in packed towers

    Energy Technology Data Exchange (ETDEWEB)

    Counce, R.M.

    1981-01-01

    A computer simulation for nitrogen oxide (NO/sub x/) scrubbing in packed towers was developed for use in process design and process control. This simulation implements a mechanistically