钒酸氧化法测定血清总胆红素的方法学评价

目的对钒酸氧化法、二氯苯胺法和改良J-G法测定血清胆红素进行方法学评价,探讨溶血、脂血对钒酸氧化法测定血清胆红素的干扰影响。方法用钒酸氧化法测定血清总胆红素,按NCCLS评价方案系统评价其重复性、回收率、线性范围和溶血、脂血对血清胆红素测定的干扰影响,并与二氯苯胺法和改良J-G法测定血清总胆红素结果进行比较。结果钒酸氧化法与二氯苯胺法和改良J-G法有良好的相关性(Y1=1.06X-0.32,r=0.94;Y2=0.93X 3.26,r=0.98);钒酸氧化法测定总胆红素的线性可达684μmol/L,批内变异为1.25%,日间变异为3.14%,回收率为102.5%;血红蛋白和甘油三酯浓度分别达6.0g/L和8.0mmol/L,无明显干扰。结论钒酸氧化法测定血清胆红素不仅简单、快速、稳定,而且线性范围宽,能抵抗溶血、脂血干扰,值得推广应用。     

Tissue-specific correction of lipogenic enzyme gene expression in diabetic rats given vanadate

Summary Vanadium is a potent insulinomimetic agent. In vivo, its blood glucose lowering action in insulin-deficient diabetic rats is associated with corrected expression of genes involved in hepatic glucose metabolism. In this study, we investigated whether vanadate treatment also reverses the impaired expression of genes coding for key enzymes of lipogenesis in diabetic liver and white adipose tissue. Oral administration of vanadate to streptozotocin-rats caused a 55% fall in plasma glucose levels after feeding without modifying low insulinaemia. It also partially corrected the low thyroid hormone concentrations. In untreated diabetic animals, hepatic mRNA levels of acetyl-CoA carboxylase and fatty acid synthase were reduced by more than 80 and 90%, respectively, in close correlation with changes in enzyme activities. Three weeks of vanadate treatment totally restored acetyl-CoA carboxylase mRNA and partially restored fatty acid synthase mRNA (71% of control levels). The activities of both lipogenic enzymes were increased 3.5 to 4-fold, to reach 45 to 65% of control values. By contrast, in white adipose tissue, vanadate modified neither expression nor activity of both lipogenic enzymes, which remained blunted (<10% of control levels). In conclusion, vanadate treatment partially restores the activities of two key lipogenic enzymes in liver, but not in white adipose tissue, of diabetic rats. This correction results from a reversal of impaired pre-translational regulatory mechanisms possibly mediated by an improvement of thyroid function and a selective restoration of liver glycolytic flux.Abbreviations ACC Acetyl-CoA carboxylase - FAS fatty acid synthase - PEPCK phosphoenolpyruvate carboxykinase - C non-diabetic control rats - D untreated diabetic rats - V vanadate-treated diabetic rats - SSC sodium saline citrate - SDS sodium dodecyl sulphate - OD optical density - kb kilobase     

五氧化二钒对大鼠发育毒性的研究

本文报道腹腔注射0.33、1.0和3.0mg/kg V_2O_5对Wistar大鼠所致的发育毒性。结果显示,在有或无明显母体毒性时,钒均可诱致畸形等发育毒性,并有一定的剂量—反应关系。综合目前对钒的研究结果,作者认为钒的致畸等发育毒性在大、小鼠间存在种属差异;钒对胚胎/胎鼠具有一定的直接作用或“双重”作用。     

Acute toxicity,twenty-eight days repeated dose toxicity and genotoxicity of vanadyl trehalose in kunming mice

A new trend has been developed using vanadium and organic ligands to form novel compounds in order to improve the beneficial actions and reduce the toxicity of vanadium compounds. In present study, vanadyl trehalose was explored the oral acute toxicity, 28 days repeated dose toxicity and genotoxicity in Kunming mice. The Median Lethal Dose (LD₅₀) of vanadyl trehalose was revealed to be 1000 mg/kg body weight in fasted Kunming mice. Stomach and intestine were demonstrated to be the main target organs of vanadyl trehalose through 28 days repeated dose toxicity study. And vanadyl trehalose also showed particular genotoxicity through mouse bone marrow micronucleus and mouse sperm malformation assay. In brief, vanadyl trehalose presented certain, but finite toxicity, which may provide experimental basis for the clinical application.     

The role of the federal government in research on nutrition and aging.

As the population of the elderly will increase 10% within the next 50 years, research on the health problems affecting them becomes pertinent. The major agency supporting biomedical and behavioral aspects of nutrition research and training is the National Institutes of Health. The research it carries out is through grants and contracts, and through a new National Program in the Clinical Nutrition Research Unit. Additional research on nutrition for the aging is performed by the US Department of Agriculture at the Tufts University Human Nutrition Research Center on Aging. The coordination of nutrition research and training at the federal level is accomplished through the Joint Subcommittee for Human Nutrition Research operating out of the Executive Office of the President.     

ROS formation and antioxidant status in brain areas of rats exposed to sodium metavanadate

In the present work, in vivo ROS formation and the activity of antioxidant enzymes in the hippocampus and the cerebellum of sodium metavanadate (NaVO₃) treated rats were studied. Rats were i.p. injected with 3 mg/kg bw/day (V₁group) or with 7.2 mg/kg bw/day of NaVO₃ (V₂group) for 5 consecutive days. Results show that after only 5 days of NaVO₃ exposure, reactive oxygen species formation and alteration of the oxidative defence system were observed. Vanadium-induced OH production was detected in cerebellum at the high dose. This result was confirmed by in situ ROS histochemical staining. Neither Cat nor Cu-Zn SOD activities showed changes while GSH/GSSG ratio, in both brain areas, was significantly decreased in NaVO₃-treated groups. The present work indicates that the NaVO₃ dose and the particular brain area constitution would be critical in the cellular and molecular oxidative mechanism of this element.     

钒对神经行为功能的影响

目的用因子分析评价钒化合物损害神经行为功能的效应特征。方法采用WHO推荐的神经行为测试组合(NCTB)测试钒接触人群(193人)和对照人群(273人)的神经行为功能。结果①提取了7个公因子,分别是消极情绪因子、注意力因子、短期视觉记忆因子、运动协调因子、运动速度和准确性因子、短期听觉记忆因子、积极情绪因子。②接钒组的运动协调、运动速度和准确性、短期听觉记忆、积极情绪低于对照组,消极情绪和短期视觉记忆高于对照组,差异均有统计学意义(P<0.05);两组注意力没有差异。结论钒化合物可增强接钒工人消极情绪和短期听觉记忆力,降低积极情绪、协调能力、短期视觉记忆力、运动速度及稳定性。     

钒对动物消化腺发育的影响

选择1日龄AA肉鸡144羽,随机分为两组,试验组添加钒30 mg/kg,试验期42 d。于每周末每组取鸡6羽,解剖取小肠、肝、胰腺称重并取材制作切片。结果:试验组肝、胰腺的平均和相对质量均高于对照组,部分差异显著或极显著;肝枯否氏细胞较大;胰腺的亮胰岛数量多、体积大;小肠腺显著或极显著长于对照组。结论:日粮中添加30 mg/kg钒,可促进肉鸡消化腺的发育。     

石墨炉原子吸收测定人发中钒含量的方法研究

本研究使用石墨炉原子吸收测定人体头发中痕量钒的含量。检出限为0.24ng/ml,灵敏度为0.026ng/0.0044A,回收率为85％—115％。结果证明,该方法具有简单、灵敏、快速、准确等优点。为临床和营养学在这方面的研究提供了一种可靠的分析方法。