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Association of Serum Folate and Vitamin B_(12) Concentrations with Obesity in Chinese Children and Adolescents
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作者 ZHU Qian Rang KOK E Dieuwertje +8 位作者 BEKELE Hailu Tesfaye MANUSAMA Koen ZHANG Jing Xian XIE Wei ZONG Wen Qi ZUO Hui ZHANG Jian KAMPMAN Ellen DAI Yue 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第3期242-253,共12页
Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents.Methods A cross-sectional study was conducted including 3,0... Objective This study aimed to evaluate the associations of serum folate and/or vitamin B12 concentrations with obesity among Chinese children and adolescents.Methods A cross-sectional study was conducted including 3,079 Chinese children and adolescents,aged 6 to 17 years,from Jiangsu,China.Anthropometric indices,such as,children's body mass index(BMI),BMI z-scores,waist circumference,and waist-to-height ratio were utilized.Multivariable linear regression and generalized additive models were used to investigate the associations of serum folate and vitamin B12 levels with anthropometric indices and odds of obesity.Results We observed that serum vitamin B12 concentrations were inversely associated with all anthropometric indices and the odds of general obesity[odds ratio(OR)=0.68;95%confidence interval(CI)=0.59,0.78]and abdominal obesity(OR=0.68;95%CI=0.60,0.77).When compared to participants with both serum vitamin levels in the two middle quartiles,those with both serum folate and vitamin B12 levels in the highest quartile were less prone to general(OR=0.31,95%CI=0.19,0.50)or abdominal obesity(OR=0.46,95%CI=0.31,0.67).Conversely,participants with vitamin B12 levels in the lowest quartile alongside folate levels in the highest quartile had higher odds of abdominal obesity(OR=2.06,95%CI=1.09,3.91).Conclusion Higher serum vitamin B12 concentrations,but not serum folate concentrations,were associated with lower odds of childhood obesity.Children and adolescents with high levels of vitamin B12 and folate were less likely to be obese. 展开更多
关键词 Folate vitamin b12 Childhood obesity MICRONUTRIENT
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Neurological Manifestations of Vitamin B12 Deficiency: About a Case
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作者 Emmanuel Yangatimbi Duval Lewis Grenaba +4 位作者 Josué Pierre Kinima Larissa Kpengougna Jacqueline Tchebemou Caprice Vivien Ndouellet Pascal Mbelesso 《Neuroscience & Medicine》 2024年第1期51-54,共4页
The authors report a case of deficient sensory neuropathy secondary to vitamin B12 deficiency, diagnosed in the neurology department of the Sino-Central African Friendship University Hospital in Bangui. The diagnosis ... The authors report a case of deficient sensory neuropathy secondary to vitamin B12 deficiency, diagnosed in the neurology department of the Sino-Central African Friendship University Hospital in Bangui. The diagnosis was made possible by electroneuromyography which showed subclinical neurological damage associated with hematological damage (anemia). Through this observation, we recall the diagnostic criteria of the disease in a context of difficult medical practice. . 展开更多
关键词 Neurological Manifestations vitamins b12 Central African Republic
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Association between metformin and vitamin B12 deficiency in patients with type 2 diabetes
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作者 Ehsan Sayedali Ali Erdinc Yalin Serap Yalin 《World Journal of Diabetes》 SCIE 2023年第5期585-593,共9页
Diabetes mellitus(DM)is still one of the most common diseases worldwide,and its prevalence is still increasing globally.According to the American and European recommendations,metformin is considered a first-line oral ... Diabetes mellitus(DM)is still one of the most common diseases worldwide,and its prevalence is still increasing globally.According to the American and European recommendations,metformin is considered a first-line oral hypoglycemic drug for controlling type 2 DM(T2DM)patients.Metformin is the ninth most often prescribed drug in the world,and at least 120 million diabetic people are estimated to receive the drug.In the last 20 years,there has been increasing evidence of vitamin B12 deficiency among metformin-treated diabetic patients.Many studies have reported that vitamin B12 deficiency is related to the malabsorption of vitamin B12 among metformin-treated T2DM patients.Vitamin B12 deficiency may have a very bad complication for the T2DM patient.In this review,we will focus on the effect of metformin on the absorption of vitamin B12 and on its proposed mechanisms in hindering vitamin B12 absorption.In addition,the review will describe the clinical outcomes of vitamin B12 deficiency in metformintreated T2DM. 展开更多
关键词 METFORMIN vitamin b 12 deficiency Diabetes mellitus vitamin b12 Type 2 diabetes mellitus
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Vitamin B3 inhibits apoptosis and promotes autophagy of isletβcells under high glucose stress 被引量:2
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作者 YU ZHANG XI’AN ZHOU +3 位作者 CHUNYAN ZHANG DENGNI LAI DONGBO LIU YANYANG WU 《BIOCELL》 SCIE 2023年第4期859-868,共10页
Background:Hyperglycemia is a typical symptom of diabetes.High glucose induces apoptosis of isletβcells.While autophagy functions in cytoprotection and autophagic cell death.The interaction between autophagy and apop... Background:Hyperglycemia is a typical symptom of diabetes.High glucose induces apoptosis of isletβcells.While autophagy functions in cytoprotection and autophagic cell death.The interaction between autophagy and apoptosis is important in the modulation of the function of isletβcells.Vitamin B3 can induce autophagy and inhibit isletβapoptosis.Method:The mechanism of vitamin B3-mediated protective effect on the function of isletβcells was explored by the method of western blot,immunofluorescence and flow cytometry.Results:In the present study,high glucose stress increased the apoptosis rate,while vitamin B3 reduced the apoptosis rate.The effect of vitamin B3 on autophagy flux under normal and high glucose stress was also investigated.Vitamin B3 increased the number of autophagosomes and increased the light chain(LC)3-II/LC3-I ratio.In contrast,vitamin B3 decreased sequestosome 1(SQSTM1)/p62 protein expression and inhibited the phosphorylation of mammalian ribosomal protein S6 kinaseβ-1(p70S6K/S6K1),which was a substrate of mammalian target of rapamycin(mTOR)under normal and high glucose stress.To further verify the protective effect of vitamin B3 on apoptosis,we treated isletβcell RIN-m5F with autophagy inhibitor 3-methyladenine(3-MA).Vitamin B3 decreased the apoptosis rate under high glucose stress,while the inhibition of apoptosis by vitamin B3 was blocked after adding 3-MA.Conclusion:Our data suggested that vitamin B3 reduced the apoptosis rate ofβcells,possibly through inducing autophagy under high glucose stress. 展开更多
关键词 vitamin b3 High glucose AUTOPHAGY APOPTOSIS
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Iron versus Iron and Vitamin B6 Supplementation in Treatment of Iron Deficiency Anemia during Second Trimester of Pregnancy: Quasi Experimental Trial
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作者 Mohamed Alaa Mohy Eldin El Ghannam Sherif Hanafi Hussain +1 位作者 Alaa Mohamed Ali Osman Sarah Safwat 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第4期814-824,共11页
Background: Anemia is one of the most prevalent complications during pregnancy. It is commonly considered a risk factor for poor pregnancy outcomes and can result in complications that threaten the life of both mother... Background: Anemia is one of the most prevalent complications during pregnancy. It is commonly considered a risk factor for poor pregnancy outcomes and can result in complications that threaten the life of both mother and fetus, such as preterm birth, and low birth weight. There is clear evidence to support prompt treatment in all patients with iron deficiency anemia because it is known that treatment improves quality of life and physical condition as well as alleviates fatigue and cognitive deficits. Objective: The aim of the study was to evaluate the value of addition of vitamin B6 to iron in treatment of iron deficiency anemia in pregnant women during the second trimester. Patients and Methods: The study was done by giving anemia pregnant women iron therapy and vitamin B6 which represent group A and iron therapy alone which represents group B. For each pregnant woman, age, parity and gestational history were taken before treatment. All pregnant women took their allocated treatment regularly for three weeks after diagnosis of iron deficiency anemia with complete blood picture and followed up after three weeks. Results: Results of the study revealed that there was no statistically significant difference between the two groups of therapy according to the hemoglobin level before treatment (p-value = 0.734), statistically significant higher mean value in after treatment than before treatment (p-value = 0.048), there was a significant difference in the rate of change of hemoglobin (p-value = 0.011) and body mass index (p-value 0.001). Conclusion: Iron and vitamin B6 seems to increase hemoglobin level more than iron only. Thus, in pregnant women with iron deficiency anemia iron plus vitamin B6 may be considered as a more effective alternative treatment than iron only. 展开更多
关键词 vitamin b6 Iron Deficiency Anemia Second Trimester HEMOGLObIN
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Vitamin B complex and vitamin B12 levels after peripheral nerve injury 被引量:6
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作者 Idiris Altun Ergül Belge Kurutas 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第5期842-845,共4页
The aim of the present study was to evaluate whether tissue levels of vitamin B complex and vitamin B12 were altered after crush-induced peripheral nerve injury in an experimental rat model. A total of 80 male Wistar ... The aim of the present study was to evaluate whether tissue levels of vitamin B complex and vitamin B12 were altered after crush-induced peripheral nerve injury in an experimental rat model. A total of 80 male Wistar rats were randomized into one control(n = 8) and six study groups(1, 6, 12, 24 hours, 3, and 7 days after experimental nerve injury; n = 12 for each group). Crush-induced peripheral nerve injury was performed on the sciatic nerves of rats in six study groups. Tissue samples from the sites of peripheral nerve injury were obtained at 1, 6, 12, 24 hours, 3 and 7 days after experimental nerve injury. Enzyme-linked immunosorbent assay results showed that tissue levels of vitamin B complex and vitamin B12 in the injured sciatic nerve were significantly greater at 1 and 12 hours after experimental nerve injury, while they were significantly lower at 7 days than in control group. Tissue level of vitamin B_(12) in the injured sciatic nerve was significantly lower at 1, 6, 12 and 24 hours than in the control group. These results suggest that tissue levels of vitamin B complex and vitamin B12 vary with progression of crush-induced peripheral nerve injury, and supplementation of these vitamins in the acute period may be beneficial for acceleration of nerve regeneration. 展开更多
关键词 nerve regeneration sciatic nerve injury vitamin b complex vitamin b12 neural regeneration
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Role of vitamin B12 deficiency in ischemic stroke risk and outcome 被引量:10
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作者 Gyllian B.Yahn Jamie E.Abato Nafisa M.Jadavji 《Neural Regeneration Research》 SCIE CAS CSCD 2021年第3期470-474,共5页
Currently,ischemic stroke is the most prevalent form of stroke compared to hemorrhagic and there is a high incidence in older adults.Nutrition is a modifiable risk factor for stroke.B-vitamins are part of a metabolic ... Currently,ischemic stroke is the most prevalent form of stroke compared to hemorrhagic and there is a high incidence in older adults.Nutrition is a modifiable risk factor for stroke.B-vitamins are part of a metabolic network that integrates nutritional signals with biosynthesis,redox homeostasis,and epigenetics.These vitamins play an essential role in the regulation of cell proliferation,stress resistance,and embryo development.A deficiency in vitamin B12 is common in older adults and has been reported to be implicated in ischemic stroke.The aim of this review was to investigate whether vitamin B12 deficiencies impact the risk and outcome of ischemic stroke.Clinical data from our literature review strongly suggest that a deficiency in vitamin B12 is a risk factor for ischemic stroke and possible outcome.Our survey of the literature has identified that there is a gap in the understanding of the mechanisms through which a vitamin B12 deficiency leads to an increased risk of stroke and outcome.A vitamin B12 deficiency can increase homocysteine levels,which are a well-established risk factor for ischemic stroke.Another potential mechanism through which vitamin B12 deficient may impact neurological function and increase risk of stroke,is changes in myelination,however this link requires further investigation.Further studies are required in model systems to understand how a vitamin B12 deficiency changes the brain. 展开更多
关键词 b-vitaminS ischemic stroke one-carbon vitamin b12
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A preliminary study on the teratogenesis of dexamethasone and the preventive effect of vitamin B_(12 )on murine embryonic palatal shelf fusion in vitro 被引量:6
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作者 Sheng-jun LU Wei HE +3 位作者 Bing SHI Tian MENG Xiao-yu LI Yu-rong LIU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第4期306-312,共7页
Excessive dexamethasone (Dex) administrated into pregnant mice during critical periods of palatal development can produce a high incidence of cleft palate. Its mechanisms remain unknown. Vitamin B12 has been shown to ... Excessive dexamethasone (Dex) administrated into pregnant mice during critical periods of palatal development can produce a high incidence of cleft palate. Its mechanisms remain unknown. Vitamin B12 has been shown to antagonize the tera- togenic effects of Dex, which, however, remains controversial. In this study, we investigated the effects of Dex and vitamin B12 on murine embryonic palatal shelf fusion using organ culture of murine embryonic shelves. The explanted palatal shelves on em- bryonic day 14 (E14) were cultured for 24, 48, 72 or 96 h in different concentrations of Dex and/or vitamin B12. The palatal shelves were examined histologically for the morphological alterations on the medial edge epithelium (MEE) and fusion rates among different groups. It was found that the palatal shelves were not fused at 72 h or less of culture in Dex group, while they were completely fused in the control and vitamin B12-treated groups at 72 and 96 h, respectively. The MEE still existed and proliferated. In Dex+vitamin B12 group the palatal shelves were fused at each time point in a similar rate to controls. These results may suggest that Dex causes teratogenesis of murine embryonic palatal shelves and vitamin B12 prevents the teratogenic effect of Dex on palatogenesis on murine embryos in vitro. 展开更多
关键词 DEXAMETHASONE vitamin b12 Organ culture Cleft oalate Medial edge epithelial cells
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Long-term metformin therapy and vitamin B12 deficiency: An association to bear in mind 被引量:8
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作者 Marco Infante Martina Leoni +1 位作者 Massimiliano Caprio Andrea Fabbri 《World Journal of Diabetes》 SCIE 2021年第7期916-931,共16页
To date,metformin remains the first-line oral glucose-lowering drug used for the treatment of type 2 diabetes thanks to its well-established long-term safety and efficacy profile.Indeed,metformin is the most widely us... To date,metformin remains the first-line oral glucose-lowering drug used for the treatment of type 2 diabetes thanks to its well-established long-term safety and efficacy profile.Indeed,metformin is the most widely used oral insulinsensitizing agent,being prescribed to more than 100 million people worldwide,including patients with prediabetes,insulin resistance,and polycystic ovary syndrome.However,over the last decades several observational studies and meta-analyses have reported a significant association between long-term metformin therapy and an increased prevalence of vitamin B12 deficiency.Of note,evidence suggests that long-term and high-dose metformin therapy impairs vitamin B12 status.Vitamin B12(also referred to as cobalamin)is a water-soluble vitamin that is mainly obtained from animal-sourced foods.At the cellular level,vitamin B12 acts as a cofactor for enzymes that play a critical role in DNA synthesis and neuroprotection.Thus,vitamin B12 deficiency can lead to a number of clinical consequences that include hematologic abnormalities(e.g.,megaloblastic anemia and formation of hypersegmented neutrophils),progressive axonal demyelination and peripheral neuropathy.Nevertheless,no definite guidelines are currently available for vitamin B12 deficiency screening in patients on metformin therapy,and vitamin B12 deficiency remains frequently unrecognized in such individuals.Therefore,in this“field of vision”article we propose a list of criteria for a cost-effective vitamin B12 deficiency screening in metformin-treated patients,which could serve as a practical guide for identifying individuals at high risk for this condition.Moreover,we discuss additional relevant topics related to this field,including:(1)The lack of consensus about the exact definition of vitamin B12 deficiency;(2)The definition of reliable biomarkers of vitamin B12 status;(3)Causes of vitamin B12 deficiency other than metformin therapy that should be identified promptly in metformin-treated patients for a proper differential diagnosis;and(4)Potential pathophysiological mechanisms underlying metformin-induced vitamin B12 deficiency.Finally,we briefly review basic concepts related to vitamin B12 supplementation for the treatment of vitamin B12 deficiency,particularly when this condition is induced by metformin. 展开更多
关键词 METFORMIN vitamin b12 deficiency Metformin-induced cobalamin deficiency Diabetes Type 2 diabetes PREDIAbETES Screening criteria NEUROPATHY ANEMIA
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Use of packed-fiber solid-phase extraction for sample clean-up and preconcentration of vitamin B_(12) before determination 被引量:5
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作者 Fang Fang Xue Jun Kang Zhi Yong Liu Yu Qin Ma Zhong Ze GU 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1491-1494,共4页
A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitami... A rapid and simple preconcentration step applying packed-fiber solid-phase extraction columns has been investigated to vitamin B12. The extraction performance of the new method was investigated preliminarily on vitamin functional drink. The analysis used a reversed-phase C18 column, with a photo-diode array detector at 220 nm. The samples were preconcentrated with packed-fiber solid-phase extraction columns. Good linearity was observed in vitamin functional drink. The repeatability of extraction performance, expressed as relative standard deviations, was from 3.5% to 4.3%. The limit of detection (LOD) is 5 ng mL^-1 (S/N = 3). Finally, the method had been applied for the determination of vitamin B12 in vitamin functional drink. 展开更多
关键词 vitamin b12 NANOFIbERS Packed-fiber solid-phase extraction PRECONCENTRATION
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CdTe quantum dots as fluorescence sensor for the determination of vitamin B6 in aqueous solution 被引量:5
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作者 Jie Fang Sun Cui Ling Ren Li Hong Liu Xing Guo Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第7期855-859,共5页
A novel, rapid and simple CdTe quantum dots (QDs) based technology platform was established for selective and sensitive determination of vitamin B6 in aqueous solution. It can perform accurate and reproducible quant... A novel, rapid and simple CdTe quantum dots (QDs) based technology platform was established for selective and sensitive determination of vitamin B6 in aqueous solution. It can perform accurate and reproducible quantification of vitamin B6 in pharmaceutical with satisfactory results. 展开更多
关键词 CdTe QDs DETERMINATION Fluorescence sensor vitamin b6
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Prostaglandin E_1 in conjunction with high doses of vitamin B_(12) improves nerve conduction velocity of patients with diabetic peripheral neuropathy 被引量:4
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作者 Jilai Li Zhirong Wan 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第5期529-532,共4页
BACKGROUND: Prostaglandin El improves diabetic peripheral neuropathy in symptoms and sensory threshold. Vitamin Bi and methyl-vitamin BI2 improve microcirculation to peripheral nerve tissue and promote neurotrophy. O... BACKGROUND: Prostaglandin El improves diabetic peripheral neuropathy in symptoms and sensory threshold. Vitamin Bi and methyl-vitamin BI2 improve microcirculation to peripheral nerve tissue and promote neurotrophy. OBJECTIVE: To observe motor nerve and sensory nerve conduction velocity in patients with diabetic peripheral neuropathy, prior to and after treatment with prostaglandin El, vitamin B I and different doses of vitamin B 12. DESIGN, TIME AND SETTING: Randomized, controlled experiment, performed at the Department of Neurology, Beijing Hantian Central Hospital, between February 2002 and September 2007. PARTICIPANTS: A total of 122 patients with type 2 diabetic peripheral neuropathy; 73 males and 49 females were included. All patients met the diagnostic criteria of diabetes mellitus, as determined by the World Health Organization in 1999 and 2006, and also the diagnostic criteria of diabetic peripheral neuropathy. For each subject, conduction disorders in the median nerve and in the common peroneal nerve were observed using electromyogram. Also, after diet and drug treatment, the blood glucose level of subjects was observed to be at a satisfactory level for more than two weeks, and the symptoms of diabetic peripheral neuropathy were not alleviated. METHODS: All patients were randomly divided into the following three groups. A control group (n = 40), in which, 100 mg vitamin B1 and 500 μg vitamin BI2 were intramuscularly injected. A vitamin B12 low-dose treated group ( n = 42), in which 10 μ g prostaglandin E1 in 250 mL physiological saline was intravenously injected once a day and 100 mg vitamin BI and 500 11 g vitamin BI2 was intramuscularly injected once a day. Lastly, a vitamin B12 high-dose treated group (n = 40), in which administration was the same as in the vitamin B12 low-dose treated group, except that 500 11 g vitamin BI2 was replaced by 1mg vitamin B12. Administration was performed for four weeks for each group. MAIN OUTCOME MEASURES: The motor nerve and sensory nerve conduction velocity of the median nerve and the common peroneal nerve were determined using an electromyogram electronic stimulator (Neuropack-11, Nihon Kohden, Japan). RESULTS: The motor nerve and sensory nerve conduction velocities of the median nerve and the common peroneal nerve were significantly faster after treatment compared to before treatment in all 3 groups (P 〈 0.05q).01). Compared with the control group, the motor nerve and sensory nerve conduction velocities were significantly faster in the vitamin B12 low-dose treated group and in the vitamin B12 high-dose treated group (P 〈 0.01). The motor nerve and sensory nerve conduction velocities were significantly faster in the vitamin B12 high-dose treated group compared to the vitamin B12 low-dose treated group (P 〈 0.05). CONCLUSION: Prostaglandin E1, in conjunction with vitamin B12, can improve neural functional states and speed up peripheral motor nerve and sensory nerve conduction velocity in diabetic peripheral neuropathy. In addition, better effects are achieved using prostaglandin E1 in conjunction with high doses of vitamin B 12. 展开更多
关键词 prostaglandin EG vitamin b 12 diabetes mellitus diabetic peripheral neuropathy
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Folate and vitamin B12 in idiopathic male infertility 被引量:2
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作者 Laurel E Murphy James L Mills +6 位作者 Anne M Molloy Cong Qian Tonia C Carter Helena Strevens Dag Wide-Swensson Aleksander Giwercman Richard J Levine 《Asian Journal of Andrology》 SCIE CAS CSCD 2011年第6期856-861,共6页
Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether i... Although methylenetetrahydrofolate reductase, a folate enzyme gene, has been associated with idiopathic male infertility, few studies have examined other folate-related metabolites and genes. We investigated whether idiopathic male infertility is associated with variants in folate, vitamin B12 (B12) and total homocysteine (tHcy)-related genes and measured these metabolites in blood. We conducted a case-control study that included 153 men with idiopathic infertility and 184 fertile male controls recruited at the Fertility Center and Antenatal Care Center, University Hospital, Malmo and Lund, Sweden. Serum folate, red cell folate (RCF), serum B12, plasma tHcy and semen quality were measured. Subjects were genotyped for 20 common variants in 12 genes related to folate/B12/ homocysteine metabolism. Metabolite concentrations and genotype distributions were compared between cases and controls using linear and logistic regression with adjustment for covariates. The phosphatidylethanolamine N-methyltransferase (PEMT) M 175V and TCblR rs173665 polymorphisms were significantly associated with infertility (P=0.01 and P=0.009, respectively), but not with semen quality. Among non-users of supplements, infertile men had lower serum folate concentrations than fertile men (12.89 vs. 14.73 nmoll^- 1 P=0.02), but there were no significant differences in RCF, B 12 or tHcy. Folate, B 12 and tHcy concentrations were not correlated with any semen parameters. This study provides little support for low folate or B12 status in the pathogenesis of idiopathic male infertility. Although additional data are needed to confirm these initial findings, our results suggest that PEMTand TCbIR, genes involved in choline and B12 metabolism, merit further investigation in idiopathic male infertility. 展开更多
关键词 folate idiopathic male infertility semen quality vitamin b12
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Influence of Different Ratios of Cobalt and Copper Supplementation on Vitamin B_(12) Status and Nutrient Utilization in Sheep 被引量:2
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作者 WANG Run-lian ZHANG Wei +1 位作者 ZHU Xiao-ping JIA Zhi-hai 《Agricultural Sciences in China》 CAS CSCD 2010年第12期1829-1835,共7页
The present study is aimed to investigate the effects of different ratios of cobalt (Co) and copper (Cu) supplementation on vitamin B12 status and nutrient utilization in sheep. Twenty wether lambs with an average... The present study is aimed to investigate the effects of different ratios of cobalt (Co) and copper (Cu) supplementation on vitamin B12 status and nutrient utilization in sheep. Twenty wether lambs with an average weight (22.9 ± 0.8) kg were randomly divided into five groups and fed with the control diet which was supplied with 0.3 mg kg^-1 DM (dry matter) of Co to the basal diet, and four supplemental diets which were supplied either 0.3 or 0.6 mg kg^-1 DM of Co and 10 or 20 mg kg^-1 DM of Cu to the basal diet, respectively for 8 wk. The supplementation of Co and Cu with different levels improved plasma vitamin B12 concentration which was increased with feeding time, but stable after 6 wk. Vitamin B12 status was accounted for Co intake with no combined effects by supplementation of different levels of Co and Cu. The plasma concentrations of methylmalonic acid, homocysteine, folic acid, and glucose did not show the consistent results with plasma vitamin B12, which was considered to be resulted from Cu action. Addition of Co and Cu with different levels had no influence on digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and nitrogen free (NFE), and N metabolism (P〉 0.05), but the digestibility of fat and fibre (P〈0.01) was enhanced by supplementation of 0.3 mg kg^-1 DM of Co and 20 mg kg^-1 DM of Cu. In conclusion, the supplementation of Co and Cu with different levels has no influence on vitamin B12 status. The optimum ratio of Co and Cu in diet could enhance the nutrient utilization. 展开更多
关键词 CObALT vitamin b12 SHEEP nutrient utilization
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Life threatening vitamin B_(12) deficiency:will timely screening make a difference? 被引量:1
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作者 T.S.Dharmarajan S. Lakshmi Narayanan Rajiv D. Poduval 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第3期456-457,共2页
INTRODUCTION While Vit.B12 deficiency is common,with aprevalence of about 15% in the elderly,andrecommendations for treatment available,detectionof deficiency at the pre-clinical stage by appropriatescreening does not... INTRODUCTION While Vit.B12 deficiency is common,with aprevalence of about 15% in the elderly,andrecommendations for treatment available,detectionof deficiency at the pre-clinical stage by appropriatescreening does not always take place.Our report isan example of life threatening Vit.B12 deficiencydiagnosed at age 56,with the onset of Vit.B12depletion likely to have begun in the 展开更多
关键词 vitamin b12 deficiency/therapy ANEMIA sickle cell gastric mucosa bIOPSY ANEMIA pernicious TOXICITY
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Vitamin B12 deficiency and gastric histopathology in older patients 被引量:1
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作者 KR Dholakia TS Dharmarajan +3 位作者 D Yadav S Oiseth EP Norkus CS Pitchumoni 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第45期7078-7083,共6页
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 histopatholog... 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. 展开更多
关键词 vitamin b12 deficiency Gastrichistopathology Older adults
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Fluorescence Spectra and Luminescent Mechanism of Vitamin b Fmily Based on Solid Powder Direct Illumination 被引量:1
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作者 张春艳 张伟刚 +3 位作者 彭雪松 严肃源 张丰 常胜江 《Journal of Measurement Science and Instrumentation》 CAS 2011年第2期112-115,共4页
The simple approach to acquire the fltaxescenee spectra of vitamin bl, b2 and t6 is proposed by direct ilhanination on solid powder sample. The experimentally acquired fluorescence spectra are in accordance with the p... The simple approach to acquire the fltaxescenee spectra of vitamin bl, b2 and t6 is proposed by direct ilhanination on solid powder sample. The experimentally acquired fluorescence spectra are in accordance with the previous measurements on soluble samples. The fluorescence spectra for a mixture of vitamins bl, b2 and b6 with different concentrations have been investigated, and the fluorescence mechanism is explained on the basis of moleoalar struchture Possible reasons of the blue-shift of the fluorescence peak and enhancement of the peak power are explained as well. The advantages of solid powder method is analyzed and discussed. 展开更多
关键词 solid powder direct illumination vitamin b fluore spectra
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Determination of Vitamin B_1 in Pharmaceutical Preparations by Flow-injection Analysis with Biamperometric Detection
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作者 LI Li-jun CHENG Hao +1 位作者 ZHAO Chuan HU Xiao-ge 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第6期650-653,共4页
A new electrochemical method for the on-line determination of vitamin B1 is presented. Based on dead-stop endpoint biamperometry by using two platinum foil electrodes with an applied potential difference of 150 mV, vi... A new electrochemical method for the on-line determination of vitamin B1 is presented. Based on dead-stop endpoint biamperometry by using two platinum foil electrodes with an applied potential difference of 150 mV, vitamin B1 can be oxidized by hexacyanoferrate ( Ⅲ ) in a sodium hydroxide medium via a reversible indicating couple Fe( CN)6^4- /Fe(CN)6^3- The cell current is linear with the concentration of vitamin B1 in the concentration range of 4. 0 × 10^-6-1.0 × 10^ -3 mol/L with a detection limit of 8.0 ×10 ^-7 mol/L(0. 27 μg/mL). Most familiar excipients, ions and vitamins do not interfere with the determination of vitamin B1. The method displays the advantages of simplicity, high efficiency( 180 samples/h), and high selectivity, and is suitable for the determination of vitamin B1 in pharmaceutical preparations. 展开更多
关键词 Pharmaceutical analysis bIAMPEROMETRY vitamin b1 How-injection analysis
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The Effect of Polymorphisms of MTHER Gene and Vitamin B on Hyperhomocysteinemia
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作者 陈健 张金枝 +1 位作者 程龙献 李裕舒 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2001年第1期17-20,共4页
The relationship between hyperhomocysteinemia and coronary artery disease (CAD) was investigated and the influence of environmental factors (Folate, VitB12) and genetic factors [N5,N10 methylenetetrahydrofolate reduc... The relationship between hyperhomocysteinemia and coronary artery disease (CAD) was investigated and the influence of environmental factors (Folate, VitB12) and genetic factors [N5,N10 methylenetetrahydrofolate reductase gene (MTHFR) or MTHFR gene mutation] on plasma homocysteine (Hcy) levels and the risk of CAD observed. Fifty one CAD patients and 30 CAD free subjects were recruited in the study. The polymorphisms of MTHFR gene were analyzed by PCR RFLP and plasma total Hcy levels were measured by high performance liquid chromatography with fluorescence detection. Plasma folate and vitamin B12 concentrations were measured by an automated chemiluminescence method. It was found that mean total plasma Hcy concentrations were significantly higher in CAD patients than in CAD free subjects ( P <0.01). The differences were also apparent among the three genotypes of MTHFR gene in CAD group ( P <0.05). There was no significant difference in the genotype distributions and allele frequencies between the two groups. A strong inverse correlation was found between folate or vitamin B12 and plasma Hcy levels according to MTHFR genotype ( P <0.01). It was concluded that hyperhomocysteinemia is a new independent risk factor for CAD. However, MTHFR gene mutation alone does not relate significantly to the morbidity of CAD since hyperhomocysteinemia and its influence on the risk of CAD are decided by both environmental and genetic factors. Supplementary treatment with vitamins B can effectively lower the plasma levels of Hcy, thus maybe reduceing the risk of CAD. 展开更多
关键词 HYPERHOMOCYSTEINEMIA coronary artery disease GENE vitamin b12 folate
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SIMULTANEOUS DETERMINATION OF VITAMIN B COMPLEX (THIAMINE, RIBOFLAVIN, NIACIN, PYRIDOXINE AND FOLIC ACID) IN FOODS BY HPLC
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作者 Ya Shan HAN Xiao Qing SONG +1 位作者 Jin Cheng ZHAO Yun Qing DAI 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第8期645-648,共4页
A high performance liquid chromatographic assay has been developed for the simultaneous determination of five water soluble vitamins:thimine, riboflavin, niacin, pyridoxine and folic acid in cereal products and fresh ... A high performance liquid chromatographic assay has been developed for the simultaneous determination of five water soluble vitamins:thimine, riboflavin, niacin, pyridoxine and folic acid in cereal products and fresh vegetables. Food samples were hydrolyzed in 0.4 mol/L HCl, autoclaved at 120℃ 15 psi for 20 minutes, using a μ-Bondapak column (3.9×300mm, Waters Co.), a mobile phase of methanol-water (30:70) (0.005 mol/L heptanesulfonic acid) and a flow rate of 1.0 ml/min gave the most satisfactory separation of the five water soluble vitamins. A double channel deteetion was used: four vitamins (B_5, folic acid, B_2, B_1) were detected hy UV spectrophotometry (254 nm) first, pyridoxine (B_6) was detected by fluoromelry (EX 290nm, EM 395 nm) afterwards. Detection limits were 2, 5, 5, 2and 5ng, linear ranges were 5-10ng, 5-50ng, 5-40ng, 5-50ng and 10-50ng for B_1, B_2, B_5, B_6 and folic acid respectively. Recoveries were 92-100%(B_5), 51-52% (folio acid), 103—105% (B_2), 99—100% (B_6) and 91.3—102% (B_1) respectively. In comparison with a reference method and checking with food composition tables, very satisfactory results were obtained by this method. 展开更多
关键词 PYRIDOXINE AND FOLIC ACID NIACIN RIbOFLAVIN SIMULTANEOUS DETERMINATION OF vitamin b COMPLEX THIAMINE IN FOODS bY HPLC
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