Maternal dietary B vitamin intake,other than folate,and the association with orofacial cleft in the offspring

Summary.Background: Periconceptional folic acid supplementation is suggested to prevent orofacial clefts (OFCs). Other B vitamins however may be beneficial as well.Aim of the study: To investigate the maternal periconceptional dietary intake of thiamine, riboflavin, niacin, pyridoxine and cobalamin in association with the occurrence of OFC.Methods: Two hundred and six mothers of a child with nonsyndromic OFC and 203 control mothers filled out a general questionnaire and a food frequency questionnaire around 14 months postpartum as a proxy for periconceptional intake. After exclusion of known pregnant and lactating mothers, those who reported to have altered their diet compared to the periconceptional period, and mothers with incidental folic acid supplement use periconceptionally, data of 182 OFC mothers and 173 controls were analysed. After logarithmic transformation, geometric means (P5-P95) were calculated and compared between the groups. After subsequent adjustment for energy, quintiles of dietary B vitamin intake were created.Results: The periconceptional intake of thiamine, niacin and pyridoxine was significantly lower in mothers of an OFC child. A trend towards risk reduction for OFC with increasing dietary intake was demonstrated for thiamine (p = 0.04) and pyridoxine (p = 0.03). Risk reductions were only demonstrated in women using folic acid supplements periconceptionally. Supplement users tended to consume a diet richer in B vitamins.Conclusions: Periconceptional intake of thiamine, niacin and pyridoxine seems to contribute to the prevention of OFC.Grant: Royal Netherlands Academy of Arts and Sciences (KNAW) Amsterdam, The Netherlands, 1997     

A pilot study evaluating the efficacy of topically applied niacin derivatives for treatment of female pattern alopecia

Background Female pattern alopecia is a common dermatologic condition that manifests after puberty. The only approved drug treatment for this condition is 2% minoxidil for topical application. Aims This pilot study examined the effect of topical application of two niacin derivatives, octyl nicotinate and tetradecyl nicotinate, on hair fullness in female alopecia. Patients/methods Sixty female subjects with Ludwig types I–III female pattern hair loss were evaluated in a double‐blinded, placebo‐controlled (40 active, 20 placebo) design using standardized 35‐mm photographic analyses for assessment of efficacy after 6 months of application. Results The niacin derivatives demonstrated a statistically significant increase in hair fullness (P = 0.04 compared to the placebo). Conclusion Whereas evaluation of hair growth in women is challenging, this 6‐month pilot study demonstrated statistically significant increase in hair fullness on blinded 35‐mm photographic analysis. Long‐term topical application of nicotinic acid derivatives offers promise for providing benefit in female alopecia and warrants further study.     

洛伐他汀烟酸缓释片的释放度研究

目的　比较自制洛伐他汀烟酸缓释片与国外制剂ALTOCOR的药物释放情况。方法　转篮法。首先以0 .5 %十二烷基硫酸钠的磷酸二氢钠溶液(pH7.0 ) 90 0mL为介质,4 5min后更换溶出介质为水90 0mL。洛伐他汀采用高效液相法测定,烟酸采用紫外分光光度法测定。结果　自制片和国外制剂ALTOCOR中洛伐他汀在4 5min内的溶出度均大于75 % ,烟酸的释放曲线均符合Higuchi方程,其相关系数分别为0 .996 8和0 .996 9。结论　自制片与国外制剂ALTOCOR中烟酸的释放曲线相似因子f2 值为99.95 ,非常相似。     

RP-HPLC法测定Beagle犬血浆中烟酸浓度及烟酸药代动力学研究

目的:建立RP -HPLC法测定血浆中烟酸的药物浓度,并将建立的方法应用于Beagle犬测定烟酸缓释片的血药浓度,计算其药代动力学参数和相对生物利用度。方法:0 .1ml血浆样品经乙腈沉淀蛋白后直接进样;流动相为乙腈 水相(8 92 ) ,水相含10mmol·L-1磷酸二氢钾,用磷酸调pH值至4 .0 ,流速为1.0ml·min-1;色谱柱为汉邦科技LichrospherC18(5 μm,2 5 0mm×4 .6mmI .D .) ,检测波长为2 6 3nm。6只Beagle犬随机交叉口服5 0 0mg复方洛伐烟酸缓释片和5 0 0mg标准参比烟酸普通片后,用RP HPLC法测定血浆中烟酸的药物浓度。结果:分析方法符合生物样品分析要求。Beagle犬单剂量口服复方洛伐烟酸缓释片5 0 0mg后,估算的末端相t1 2 为1.3±1.2h ,Tmax为2 .3±0 .8h ,Cmax为35 .3±4 .9mg·L-1,MRT为3.5±0 .6h。复方洛伐烟酸缓释片的AUC、Cmax 明显低于烟酸普通片(P <0 .0 5 )。经配对t检验分析显示复方洛伐烟酸缓释片Tmax明显长于普通片(P <0 .0 5 )。结论:单剂量口服复方洛伐烟酸缓释片后,测得的Cmax和AUC与烟酸普通片均有显著性差异,受试缓释片的Tmax长于参比普通片,Cmax低于参比普通片,说明受试缓释片无突释现象,有一定的缓释效果。     

FORMS OF BOUND NIACIN IN WHEAT

Further studies on the bound form of niacin in wheat show that a number of niacin-containing macromolecules are present. These indicate that structural work on these macromolecules is required before the reasons for the unavailability of niacin are understood.     

Opaque-2 maize in the prevention and treatment of pellagra

In order to determine the usefulness of opaque-2 maize in the prevention of pellagra, people from the third and fifth brigades of a commune in a maize-eating district of Northwest China received opaque-2 maize in their diet and served as the experimental subjects. People from the neighboring sixth brigade ate conventional maize and served as the control subjects. After three months there were no cases of pellagra in the experimental groups, but there were three cases in the control group; the incidence was 1.8%.Prior to the study, urinary excretion values of N-methylniacinamide (N-MN) of the subjects were measured. There were no significant differences among the three brigades (P>0.05). By the conclusion of the study the differences in urinary excretion of N-MN between the experimental and control groups were highly significant: 0.21±0.02 and 0.21±0.02 mg/2 h for the experimental groups and 0.12±0.01 mg/2 h for the control group.Opaque-2 maize also was used in a study of the treatment of pellagra. Persons with pellagra were divided into three groups: Group 1 received opaque-2 maize, Group 2 received conventional maize plus niacinamide (10 mg per day), and Group 3 received conventional maize. Before treatment, the average values of the urinary excretion of N-MN of each group were not significantly different. After one month of the treatment, a loading dose of 50 mg niacinamide was administered orally. Four-hour urines were collected and analyzed for N-MN. The differences between Group 1 and Group 3 or Group 2 and Group 3 were significant. Although the results showed that opaque-2 maize could be used in the prevention and treatment of pellagra, meat, milk, and milk products should be recommended to people in all of the areas where pellagra is endemic. The planting of opaque-2 maize, however, should provide an effective means to supply utilizable niacin and is a simple, economical way to prevent pellagra for the present.     

B Vitamins and the Brain: Mechanisms,Dose and Efficacy—A Review

The B-vitamins comprise a group of eight water soluble vitamins that perform essential, closely inter-related roles in cellular functioning, acting as co-enzymes in a vast array of catabolic and anabolic enzymatic reactions. Their collective effects are particularly prevalent to numerous aspects of brain function, including energy production, DNA/RNA synthesis/repair, genomic and non-genomic methylation, and the synthesis of numerous neurochemicals and signaling molecules. However, human epidemiological and controlled trial investigations, and the resultant scientific commentary, have focused almost exclusively on the small sub-set of vitamins (B₉/B₁₂/B₆) that are the most prominent (but not the exclusive) B-vitamins involved in homocysteine metabolism. Scant regard has been paid to the other B vitamins. This review describes the closely inter-related functions of the eight B-vitamins and marshals evidence suggesting that adequate levels of all members of this group of micronutrients are essential for optimal physiological and neurological functioning. Furthermore, evidence from human research clearly shows both that a significant proportion of the populations of developed countries suffer from deficiencies or insufficiencies in one or more of this group of vitamins, and that, in the absence of an optimal diet, administration of the entire B-vitamin group, rather than a small sub-set, at doses greatly in excess of the current governmental recommendations, would be a rational approach for preserving brain health.