耗竭-补充营养素对初断乳大鼠进食量及体重的影响

目的：观察锌(Zn)、维生素A(VA)、维生素B2(VB2)缺乏和补充对初断乳大鼠进食量、体重的影响。方法：通过耗竭一补充方式造成初断乳大鼠的Zn、VA、VB2单独和联合缺乏模型，后强化补充相应营养素，动态检测大鼠进食量、体重的变化。结果：Zn、VA、VB2缺乏时不同程度地影响大鼠进食量、体重，以联合缺乏影响最为突出；强化补充相应营养素后，大鼠进食量、体重均得到改善，但仍达不到正常发育水平。结论：婴幼期Zn、VA、VB2缺乏或不足可影响生长发育，应充分重视婴幼儿营养。     

甲状腺功能亢进症患者血清锌、铁、铜、钙的测定及意义

目的探讨甲状腺功能亢进症病人血清中Zn、Fe、Cu、Ca浓度的变化及其意义。方法检测30例患者血清中Zn、Fe、Cu、Ca4种元素,同时随机检测与甲亢患者年龄构成比相匹配的30例正常体检者作正常对照。结果甲状腺功能亢进症患者血清中Zn、Fe、Cu元素水平明显高于对照组(P<0.01),两组间Ca浓度比较无统计学意义。结论甲亢患者体内可出现多种元素的代谢异常,此变化既能反应病人机体代谢紊乱程度,同时也可以作为病情监测的参考指标。血清Fe、Zn、Cu的测定对反映甲亢的病情控制及预后判断有一定的临床价值。     

Structure-activity relationship of macrocyclic and linear gadolinium chelates: Investigation of transmetallation effect on the zinc-dependent metallopeptidase angiotensin-converting enzyme

Transmetallation between commercially available solutions of gadolinium (Gd) chelates and the zinc (Zn)-dependent angiotensin-converting enzyme (ACE) was investigated. In vitro, the strongest inhibitions were observed for the linear Gd complexes, Gd diethylene-triamine pentaacetic acid (DTPA) bis-methylamide (BMA) (IC₅₀ = .016 ± .006 mmol/1) and Gd-DTPA (IC₅₀ = .350 ± .034 mmol/1). The two macrocycles Gd tetraazacyclododecane tetraacetic acid (DOTA) and Gd-HP-DO3A were similar and 400 times less active than Gd-DTPA-BMA. These effects were mainly due to the presence of free ligand for DTPA and calcium (Ca) chelate in the case of DTPA-BMA because the addition of Zn²⁺ in the same quantities suppresses their inhibitory effects. In vivo, these two solutions of linear Gd chelates significantly inhibited ACE activity (Gd-DTPA: 67 ± 9% versus baseline; and Gd-DTPA-BMA: 73 ± 2% versus baseline at the clinical dose of .1 mmol/kg), whereas no significant effect was observed for the two macrocyclic chelates Gd-DOTA and Gd-HP-DO3A. Formulating the Gd chelate solution with either an excess of free ligand or Ca chelate (to decrease Gd³⁺ release) in the case of linear Gd chelate may have deleterious biologic consequences.     

妊娠期血清微量元素的变化

目的探讨妊娠期血清微量元素的变化规律。方法以原子吸收分光光度法分别测定421例孕妇和128例正常对照妇女血清铜(Cu)、锌(Zn)、铁(Fe)等微量元素浓度和血清镁(Mg)、钙(Ca)浓度。结果血清铜(Cu)在整个孕期内无显著性变化,P>0.05;血清锌(Zn)、铁(Fe)、镁(Mg)、钙(Ca)随孕期的增加而降低,P均<0.05。结论孕妇在妊娠期内应根据不同孕期,合理补充微量元素。     

饮食性缺铜、缺锌对小鼠细胞因子产生的影响

３周龄小鼠饲用６周缺铜饮食后，出现胸腺萎缩、肝脏肿大以及明显的缺铜指征，包括血清Ｃｐ活性、肝Ｃｕ含量、ＣＣＯ和Ｃｕ，Ｚｎ－ＳＯＤ活性明显下降。缺钢小鼠产生的ＴＮＦ－α、ＩＬ－１和ＩＬ－６水平明显低于正常组小鼠。小鼠饲予７周缺锌饮食后，出现明显脱毛，虽然肝Ｚｎ含量降低不明显，但ＴＮＦ－α、ＩＬ－１和ＩＬ－６活性明显降低，说明上述细胞因子是小鼠缺锌的敏感指征之一。本文结果显示正常Ｃｕ、Ｚｎ水平对ＴＮＦ－α、ＩＬ－１和ＩＬ－６产生的重要性，并提示这些细胞因子的改变可能是缺铜、缺锌引起的免疫功能损害的细胞、分子学机理之一。     

Zn~(2+)预处理对离体大鼠缺血再灌注损伤心肌的保护作用

目的 :观察Zn2 + 预处理诱导金属硫蛋白 (MT)在心肌细胞的表达及对离体大鼠缺血再灌注损伤心肌的保护作用。方法 :3 2只Sprague Dawley大鼠随机分为对照组及实验组 ,实验组按腹腔注射ZnSO4 到建立再灌注模型的时间分为E1 2h,E2 4h及E4 8h组 ,每组各 8只。检测LDH ,CK、ATP含量及心功能指标 (LVSP与±dp/dtmax) ,用1 0 9Cd/血红素饱和法测量心肌组织中金属硫蛋白的含量。结果 :E2 4h及E4 8h组MT表达量较对照组高 (P <0 .0 1) ,E1 2h组虽有表达 ,但其与对照组间差异无显著性。E2 4h及E4 8h组LDH与CK较其它二组低 ,而ATP较其它二组高 ,心功能指标较其它二组改善。E1 2h组及对照组之间相应各指标 (LDH ,CK、ATP、LVSP与±dp/dtmax)间差异无显著性 (P >0 .0 5 )。结论 :Zn2 + 预处理可诱导MT在心肌细胞的表达而对离体大鼠缺血再灌注损伤心肌具有保护作用。     

我国正常生育力男子精浆的微量元素研究

本文报告测试了68例正常生育力成年男子精浆中的锌、铜,铁等微量元素和镁,测试结果如下:锌130±5.64μg/ml,铜1.84±0.158μg/ml,铁0.801±0.104μg/ml,镁103.86±10.01μg/ml。所测得的数值均在正常范围内。在正常范围内的精液,精浆中的锌、镁含量与精液质量(精子密度和活动力)之间无显著差异。但铜的含量与精子活动度关系密切,含量高则活动度差,反之则活动度好。铁的含量与精子密度关系也十分密切,含量高时精子密度也高。     

Effect of maternal cadmium exposure on postnatal development and tissue cadmium,copper and zinc concentrations in rats

Administration of 60 ppm cadmium (Cd) in drinking water from the 1^st to the 20^th day of gestation to female rats did not affect the viability, body weight gain, food, and water consumption of offspring. The blood hemoglobin level was reduced in 2-week-old females and males but not in 16-week-old offspring. Hematocrit and serum glucose level were not affected at either age. Cadmium concentration in the intestinal wall was increased in both age groups, with marginal uptake in other organs. A decrease in copper (Cu) concentration was found in the brain of 2-week-old offspring of both sexes and of 16-week-old females. The brain zinc (Zn) concentration was decreased only in 16-week-old animals. The physical and neuromuscular development of offspring before weaning was not impaired by maternal Cd treatment. The alterations in Cu and Zn metabolism were associated with reduced locomotor activity and affected open-field behavior in adult offspring of either sex and with decreased avoidance acquisition in adult female offspring.The results obtained suggest a relationship between the reduced brain Cu and Zn levels and CNS dysfunction in adult offspring of female rats exposed to Cd during gestation.     

The effects of CaEDTA injection on lead,zinc, copper and ALAD in erythrocyte,plasma and urine in lead-exposed workers: a 24-h observation

Summary To evaluate the effects of calcium disodium ethylenediamine tetraacetate (CaEDTA) on the concentrations of lead, zinc and copper in plasma, erythrocyte and urine, and the delta-aminolevulinic acid dehydratase (ALAD) activity in erytrocyte, we administered CaEDTA in 1-h intravenous infusion to ten male gun metal founders with blood-lead concentration of 39 to 64 g/dl (mean 49 g/dl). We found that the plasma concentration of lead, following a rapid rise within the first 3 h, fell temporarily to the level significantly lower than the initial level 19 h after start of the infusion. The plasma concentration of zinc fell to the minimal level 5 h after the infusion; and the erythrocyte concentration of zinc and the ALAD activity concurrently rose to the maximal level 5 h after the infusion. By contrast, no significant alteration was observed in the concentrations of copper in plasma and erythrocyte. The maximal level of urinary metal excretion was attained during the period between 1 and 2 h after start of CaEDTA infusion for lead; within 2 h for zinc; and between 2 and 4 h for copper. The urinary metal excretion returned to the initial level 14 to 24 h after infusion for zinc and copper; but lead excretion was still higher than the initial level during this period. The difference in the kinetics of the three metals following CaEDTA injection is discussed in the light of these findings.     

锌对小鼠组织MT-1基因转录及MT蛋白表达的影响

目的 :研究锌对小鼠各脏器金属硫蛋白 (MT)基因表达的影响。方法 :将小鼠随机分为注锌组和对照组 ,注锌后不同时间或不同剂量锌注射后 16 h断头处死动物 ,取一定量肝、脑、胸腺及脾脏组织制成匀浆 ,采用 Northern blot及 10 9Cd- hem饱和法测定组织 MT基因转录及蛋白表达的变化。结果 :时程研究表明 ,锌 10 mg/ kg腹腔注射后 2 h,小鼠肝脏及脾脏 MT- 1m RNA水平明显升高 ,4 h达峰值 ,分别为对照组的 5 .30和 2 .92倍 ,2 4 h恢复至正常水平 ;其 MT蛋白表达迟于 MT- 1m RNA水平升高 ,注锌后 8～ 2 4 h肝脏及脾脏 MT蛋白含量均比对照组明显升高 (P<0 .0 5或 P<0 .0 0 1) ,2 4 h达峰值 ,72 h恢复至正常水平。注射不同剂量锌后小鼠肝脏及脾脏 MT- 1m RNA水平 (4h)和 MT蛋白含量 (16 h)均呈剂量依赖性增加。小鼠腹腔注射锌 2 .5～ 10 mg/ kg 16 h,小鼠肝脏或脾脏 MT含量或锌5～ 10 mg/ kg注射后脾脏 MT含量均显著高于对照组 (P<0 .0 1或 P<0 .0 0 1)。但注射锌后脑及胸腺MT- 1m RNA水平及 MT蛋白含量均无明显变化经。结论 :锌诱导小鼠组织 MT合成具有明显的组织器官特异性。