Vitamin B12 Deficiency.

U.S. Army Health Clinic, Darmstadt, Germany.
American family physician (Impact Factor: 1.82). 04/2003; 67(5):979-86.
Source: PubMed

ABSTRACT 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.

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Available from: Robert C Oh, Aug 17, 2015
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    • "The deficiency of Vitamin B 12 may cause some disorders such as hematologic, neuropsychiatric and cardiovascular disorders. According to the clinical findings, patients whose blood serum levels of Vitamin B 12 are lower than 200 pg/mL (150 pmol/L) are diagnosed with Vitamin B 12 deficiency [35]. Therefore, the determination of the level of Vitamin B 12 is very important for blood, drugs, dairy products, and fermentation products . "
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    ABSTRACT: In this study, peptide nanostructures from diphenylalanine were synthesized in various solvents with various polarities and characterized with Scanning Electron Microscopy (SEM) and Powder X-ray Diffraction (PXRD) techniques. Formation of peptide nanofibrils, nanovesicles, nanoribbons, and nanotubes was observed in different solvent mediums. In order to investigate the effects of peptide nanotubes (PNT) on electrochemical behavior of disposable pencil graphite electrodes (PGE), electrode surfaces were modified with fabricated peptide nanotubes. Electrochemical activity of the pencil graphite electrode was increased with the deposition of PNTs on the surface. The effects of the solvent type, the peptide nanotube concentration, and the passive adsorption time of peptide nanotubes on pencil graphite electrode were studied. For further electrochemical studies, electrodes were modified for 30 min by immobilizing PNTs, which were prepared in water at 6 mg/mL concentration. Vitamin B12 analyses were performed by the Square Wave (SW) voltammetry method using modified PGEs. The obtained data showed linearity over the range of 0.2 μM and 9.50 μM Vitamin B12 concentration with high sensitivity. Results showed that PNT modified PGEs were highly simple, fast, cost effective, and feasible for the electro-analytical determination of Vitamin B12 in real samples.
    Applied Surface Science 06/2014; 303:37–45. DOI:10.1016/j.apsusc.2014.02.039 · 2.54 Impact Factor
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    • "Nevertheless, the so-called subclinical cobalamin deficiency (SCCD) in clinically normal individuals exhibiting biochemical abnormalities can be associated with subtle neurological and electrophysiological changes and calls for further workup of such patients (Carmel, 2008). The prevalence of cobalamin deficiency increases with age and is present in 1.9–15% of the elderly (Oh & Brown, 2003; McLean, de Benoist & Allen, 2008; Carmel, 2011). The prevalence varies according to the disease definitions, markers, and cutoffs employed. "
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    ABSTRACT: After measurement of the mean volumes of leukocyte subpopulations as well as the distribution widths (DW) of these volumes has become available, we investigated whether such morphometric leukocyte parameters are associated with a commonly used marker of cobalamin deficiency, i.e., holotranscobalamin (HoloTC). Further, we determined reference intervals for these parameters in an elderly population. Consecutive subjectively healthy and volunteering individuals ≥60 years were included. Using the UniCel DxH 800 Coulter Cellular Analysis System MoMV, mean neutrophil volume (NeMV), mean lymphocyte volume (LyMV), monocyte anisocytosis (MoV-DW), neutrophil anisocytosis (NeV-DW), and lymphocyte anisocytosis (LyV-DW) were assessed together with other parameters including HoloTC. A total of 150 individuals were included in the study. Reference intervals were not dependent on age and gender. MoV-DW (P = 0.002) and NeV-DW (P = 0.02) were significantly lower, and LyMV was significantly higher (P = 0.04) in participants with a HoloTC concentration <28 pm. In contrast, MCV, MoMV, NeMV, and LyV-DW were not associated with HoloTC concentrations. The area under the curve (AUC) in the receiver operating characteristic analysis for detecting a HoloTC <28 pm was 0.81 [95% confidence interval (CI) (0.73, 0.87)] for MoV-DW and 0.73 (0.66, 0.80) for NeV-DW. In this collective of subjectively healthy elderly individuals, monocyte anisocytosis, neutrophil anisocytosis and mean lymphocyte volume were associated with decreased HoloTC.
    International journal of laboratory hematology 11/2011; 34(2):192-200. DOI:10.1111/j.1751-553X.2011.01382.x · 1.87 Impact Factor
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    • "While micronutrient and omega-3 status are important, other factors such as smoking, sedentary lifestyles and obesity influence disease risk. Nutrient status is affected by low dietary intakes and reduced nutrient absorption (Oh and Brown, 2003). A varied diet which includes plenty of fruit, vegetables, wholegrains, fish, lean meat and poultry, low-fat dairy foods and starchy carbohydrates should be the bedrock of dietary intervention. "
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    ABSTRACT: Purpose – The purpose of this paper is to examine the potential role of micronutrients and omega-3 fatty acids in promoting healthier ageing. Design/methodology/approach – A literature review was conducted using Medline and key words relevant to ageing, nutritional status, nutrient intake and disease risk. Data from the National Diet and Nutrition Survey (NDNS) were used to determine micronutrient adequacy. Findings – The NDNS showed that intakes of vitamin A, B2, B6, folic acid, iron, calcium, magnesium, zinc and iodine fell below recommended levels for groups of older people. Vitamins and mineral supplements may improve nutritional status, lower the risk of deficiency, and impact favourably on disease markers. Practical implications – The evidence suggests that dietary interventions and supplementation may become increasingly important in maintaining health and quality of life in older people. Originality/value – This paper highlights the positive role of nutrition in healthy ageing.
    Nutrition & Food Science 10/2011; 41(6):420-429. DOI:10.1108/00346651111181976
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