离子对反相高效液相色谱同时测定饮品中Vpp,VB6及咖啡因含量

建立了离子对反相高效液相谱色（ＨＰＣ）同时测定饮吕中ＶＰＰ、ＶＢ６和咖啡因的方法。以庚烷磺酸钠为离子对试剂,甲醇：水２：８（１％冰乙酸）为流动相。ＶＰＰ、ＶＢ６及咖啡因的线性范围分别是４０－２００μｇ／ｍｌ、８－４０μｇ／ｍｌ及５０－２５０μｇ／ｍｌ。回收率分别为９８．５０－１０１．８％、９９．６０－１０４．０％、及９９．３０－１０２．５％。该法可用于饮品中ＶＰＰ、ＶＢ６及咖啡因的含量测定,对３批     

儿童血清抗氧化维生素水平及其干预研究

目的　了解不同营养状态儿童维生素摄入情况、血清抗氧化维生素水平及其干预效果。方法　对北京市 2 94名 7～ 1 1岁儿童 (其中肥胖 1 57名、超重 68名、体重正常 69名 )进行了 3d记录法调查膳食维生素摄入情况、血清维生素 (α -生育酚、β -胡萝卜素及维生素A、维生素C)水平 ,并进行 6个月的维生素E、C合剂 (每日维生素E 1 0mg ,维生素C 80mg)干预。结果　随肥胖度增加 ,血清维生素A上升、α -生育酚下降 ,差异无显著性 (P >0 .0 5) ;β -胡萝卜素下降 ,差异有显著性 (P <0 .0 5)。肥胖儿童维生素E摄入低于体重正常儿童 ,但差异无显著性 (P >0 .0 5)。服用维生素E、C合剂 6个月 ,血清α -生育酚、维生素C水平升高。结论　肥胖儿童血清抗氧化维生素水平低于体重正常儿童 ,服用日常供给量维生素E、C ,可以提高血清α-生育酚和维生素C水平     

Lack of antioxidative properties of vitamin C and pyruvate in cultured retinal pigment epithelial cells

Background Oxidative damage to the retinal pigment epithelium might be involved in the pathogenesis of age related macular degeneration. Thus antioxidative protection represents a rationale for a causative therapy or prophylaxis. The aim of the present study is to evaluate antioxidative properties of vitamin C and pyruvate at retinal pigment epithelial (RPE) cells exposed to oxidative stress. Methods The ability of vitamin C and pyruvate to quench hydroxyl radicals was tested using the di-hydro-rhodamine (DHR) assay. Cells of the human RPE cell line ARPE-19 were exposed for 8 min to hydroxyl radicals generated by the Fenton reaction from 2.25 mM H₂O₂ and 30 μM Fe³⁺-nitrilo-tri-acetate. This was done in the absence and presence of 0.3–3.0 mM pyruvate and vitamin C, respectively. Cell survival was analysed by vitality staining (life-dead-assay) and expressed as cell survival ratio. A survival ratio <1.0 indicates cell loss. Results At concentrations from 0.1 to 1.0 mM vitamin C and pyruvate quench hydroxyl radicals in the DHR assay in absence of living matter. In the presence of 0.1– 0.3 mM vitamin C and pyruvate, ARPE-19 showed a reduced survival ratio (0.87±0.01 to 0.89±0.02 after 6 h) which was not the case at the higher concentrations between 1 and 3 mM. The exposure of ARPE-19 cells to hydroxyl radicals reduced the survival ratio to 0.92±0.02. At concentrations at which vitamin C and pyruvate exert toxic effects, a potentiation of radical induced cell death can be observed (survival ratio 0.79±0.02 and 0.82±0.03, respectively). Higher concentrations of vitamin C or pyruvate had no explicit protective effect to the hydroxyl radical induced damage. Discussion Although vitamin C and pyruvate are potent hydroxyl radical quenchers in vitro they failed to protect cultured ARPE-19 cells from oxidative stress induced cell death. In contrast, when applying the scavengers at low concentrations a potentiation of cell damage was observed. Part of this work has been presented at the DOG/SOE meeting in September 2005 in Berlin (programme #2809-3.06 presentation given by Oliver Zeitz). Oliver Zeitz and Lars Schlichting contributed equally.     

Reference range for micronutrients and nutritional marker proteins in cord blood of neonates appropriated for gestational ages

BACKGROUND: Reference values of numerous micronutrients at different gestational ages (GA) have not been yet reported based on large series. AIMS: This study aimed to establish the reference range for zinc, copper, selenium, vitamin A, vitamin E, retinol binding protein, transthyretin, albumin, transferrin and ceruloplasmin in neonates and to give the profiles according to gestational age. STUDY DESIGN: A total of 510 infants appropriate for gestational age were included in the study. The determinations were done using the serum cord blood of 262 term and 248 preterm infants (gestational age of 37 to 42 and 26 to 36 weeks, respectively). RESULTS: All nutrients correlated significantly with birth weight and gestational age but different patterns were highlighted. Vitamin A, retinol binding protein and prealbumin showed a triphasic pattern with a cut-off at about 36 to 39 weeks. In this period, these parameters rised significantly (P<0.001). Albumin and selenium showed a biphasic pattern with a significant positive correlation (P<0.001) between weeks 26 to 38. Transferrin and ceruloplasmin associated with copper showed a continuous increase with GA (P<0.001). On the opposite, zinc and vitamin E decreased. Zinc showed a biphasic pattern with a significant negative correlation (P<0.001) between the 26th to 34th weeks. Vitamin E presented a triphasic pattern with a cut-off at about 32 to 35 weeks (P<0.001). CONCLUSION: The large number of data allow the build-up of reference ranges and charts for the evaluation of micronutrients and proteins in high-risk neonates.     

B族维生素在肾移植受者高同型半胱氨酸血症及内皮功能异常治疗中的应用

目的探讨B族维生素治疗肾移植受者高同型半胱氨酸血症效果,对内皮功能的影响。方法将36例接受首次肾移植后的高同型半胱氨酸患者,随机分为两组,观察组18例,口服叶酸5mg/d,维生素B650mg/d及维生素B121000μg/d,连续6个月;对照组18例。分别于治疗前和治疗6个月时观察血肌酐水平和肌酐清除率,平均血压值,血胆固醇、甘油三酯和同型半胱氨酸水平变化,应用彩色多普勒超声测定内皮功能。结果观察组患者治疗后同型半胱氨酸与治疗前相比显著降低[(13±4)μmol/L与(20±5)μmol/L,t=5.3,P<0.01];肱动脉反应性充血时内径变化百分率[(12±5)%与(9±5)%,t=2.9,P<0.01]和含服硝酸甘油后肱动脉内径变化百分率[(18±4)%与(12±5)%,t=3.4,P<0.01]均显著增加。其他指标无显著改变。对照组6个月后各项指标与治疗前相比差异无统计学意义;肱动脉反应性充血时内径变化百分率为(9±6)%,含服硝酸甘油后肱动脉内径变化百分率为(12±5)%,均显著低于观察组(t=2.8,P<0.01;t=3.5,P<0.01)。结论应用叶酸、维生素B6及维生素B12能够有效治疗肾移植受者的高同型半胱氨酸血症,并使内皮功能获得明显改善。     

Impact of nutritional status and nutrient supplements on immune responses and incidence of infection in older individuals

With advancing age there is a progressive decline in immune responses although this is not inevitable. The impairment in immunocompetence is noticeable as early as 35-40 years in many individuals. At the same time, some persons even in the 80s may show a vigorous immune system comparable with that of the young adult. Nutrient deficiencies are frequent in older populations. A variety of nutrients are affected: zinc, iron, beta-carotene, Vitamins B6, B12, C, D and E, ad folic acid. The causal interaction between nutritional deficiencies and impaired immunity has been known in children; a similar relationship has been postulated in the elderly. In the last 25 years, many studies employing different designs have examined the role of diet, nutritional status, and nutrient supplements in the immune responses of older individuals. Some nutrients, for example zinc and Vitamin E, have been shown to increase selected immune responses but have not been beneficial in terms of reduction in infectious morbidity. A growing consensus indicates that the use of a multinutrient containing optimum amounts of essential trace elements and vitamins is likely to result in enhanced immune responses and reduction in the occurrence of common infections. These findings have considerable fundamental, clinical and public health significance.     

Alcohol-nutrition interaction: 1984 update

Alcohol remains a prevailing cause of malnutrition resulting in a variety of deficiency states secondary to decreased intake of nutrients. In addition to various well described primary malnutrition syndromes, secondary malnutrition may result from the interaction of ethanol with nutrient digestion, absorption or utilization. Some of the latter alcohol-nutrient interactions have been recently defined and their pathogenesis is discussed in this review. Included are interactions with thiamine, folic acid, vitamin A and disorders secondary to amino acid imbalances. The rationale for various forms of therapy is reviewed, including the treatment aimed at correcting the “hypermetabolic state” in alcoholics and the pitfalls of excess nutrient administration (particularly as it pertains to pyridoxine, vitamin A and amino acids). The desirability of recognizing early precirrhotic stages of alcoholic fibrosis is emphasized, in order to start therapy prior to the medical and/or social disintegration of the alcoholic.     

Changes in time-trends of nutrient intake from fortified and non-fortified food in German children and adolescents--15 year results of the DONALD study. Dortmund Nutritional and Anthropometric Longitudinally Designed Study

Summary Background: Although fortified products have played an increasing role in food marketing since the 1980 s in Germany, data as to the consumption of fortified food is sparse. Aim of the study: To assess long-term data on changes in fortified food supply or consumption patterns, nutrient intake, and time trends in the DONALD Study (Dortmund Nutritional and Anthropometric Longitudinally Designed Study). Methods: Between 1985 and 2000 consumption of nutrient intake (total and from fortified foods) was evaluated and time trends in energy and nutrient intake were assessed on the basis of 3-day weighed dietary records (n = 4193) of 2–14 year-old males (n = 383) and females (n = 404) enrolled in the DONALD Study. Nutrient intake was expressed as percentage of the current German recommendations. Food products were defined as fortified if enriched with at least one of the following nutrients: Vitamin A or provitamin A carotenoids (summarised as Vitamin A), Vitamins E, B1, B2, B6, C, niacin, folate, calcium or iron. Nutrient supplements and medicine were excluded from this evaluation. Time trends were analysed using linear and non-linear regression models (PROC MIXED, SAS^? 6.12). Results: In percent of German references [3], non-fortified food contributed to folate intake by 20–30 %, to Vitamin E by about 40 %, to Vitamin B1 by 50–65 %, to Vitamin A, C, B2, calcium, iron by about 65–95 %, and to Vitamin B6 and niacin intake by 100 % and more. Fortified food alone provided no more than 5 % of calcium intake, about 10–20 % of iron, Vitamin A and folate intake, up to 40–50 % of Vitamin C, B 1, B2, E, niacin and up to 80 % of Vitamin B6 intake. During the 15 year period of the DONALD Study with total food, we only found a significant linear time trend for Vitamin C, whereas significant non-linear time trends were found for calcium, Vitamin E, B1, B2, B6, niacin and folate. In the latter there was a uniform increase until 1994 and a decrease thereafter. For iron and Vitamin A no significant time trend could be identified. Only iron and Vitamin A intake from fortified food showed a significant linear time trend. All other nutrients studied here gave significant non-linear time trends. Nutrient intake with fortified food reached maximum values between 1994 and 1996 followed by a decrease thereafter. Conclusions: Signs of changing food consumption patterns were found, pointing to an almost uniform decrease of nutrient intake since 1994/96 in our population of German children and adolescents. This could be an alarming indicator of a slight but unpreferable tendency to eat energydense, nutrient-poor foods. Received: 22 January 2001 / Accepted: 19 April 2001     

Effects of α-tocopherol, β-carotene and ascorbic acid on oxidative, hormonal and enzymatic exercise stress markers in habitual training activity of professional basketball players

Summary Background Intense physical exercise has been associated with an increase of free radical production. When the body's natural defense systems against free radicals are overwhelmed, oxidative stress increases. Aim of the study This study examined the effects of a vitamin antioxidant supplement, (composed of 600 mg α-tocopherol, 1000 mg ascorbic acid and 32 mg β-carotene) on oxidative, hormonal, and enzymatic exercise stress markers during habitual training activity over 35 days. Methods The plasma concentrations of ascorbic acid, α-tocopherol, β-carotene, testosterone, cortisol and lipid peroxides and the serum activities of lactate dehydrogenase and creatine kinase were measured at four time points: pre-supplementation (PS), pre-training (PT), after training (AT) and 24h after training (24h-AT) in 13 professional basketball players of the first Spanish Basketball League (ACB). Results Antioxidant supplementation led to a significant increase of α-tocopherol and β-carotene from PS to PT. Plasma lipid peroxides decreased about 27.7 % after 35 days of antioxidant treatment. A significant decrease of lactate dehydrogenase serum activity was observed during the 24h recuperation time. During this time the anabolic/catabolic balance increased about 29.8 % in the antioxidant supplemented group, although this increase did not reach statistical significance. Conclusions The results of the present study suggest that supplementation with α-tocopherol, β-carotene and ascorbic acid might partially account for the hormonal and enzymatic stress marker profile observed during habitual training activity of professional basketball players. Received: 30 October 2000, Accepted: 9 October 2001