黄酮类稀土金属配合物的研究进展

黄酮类化合物是一类重要的中药有效成分,现代研究表明稀土金属在生物医药领域也有很大的应用前景。稀土配合物的合成主要是集中在将具有特定生物活性的配体与稀土离子配合,以期达到更好的生物活性。现对近年来黄酮类稀土金属配合物的合成方法和生物活性进行综述,为今后的黄酮类稀土金属配合物的深入研究提供理论支持。     

稀土元素镧、铈对铁皮石斛组培苗生长影响的研究

目的 探讨添加稀土元素镧、铈对铁皮石斛组培苗以及移栽后铁皮石斛苗的生长的影响,寻找能显著促进铁皮石斛生长发育的稀土元素,以获得品质优良的铁皮石斛苗.方法 以铁皮石斛小苗为外植体,通过添加不同浓度硝酸镧、硝酸铈的培养基上进行培养,并对其性状特征、生理活性、移栽后生长状况等进行统计比较研究.结果 通过90 d的培养后,添加稀土元素组别的铁皮石斛的鲜质量、根数、株高、叶绿素含量均高于空白组,分蘖数低于空白组,而且随着硝酸镧和硝酸铈浓度的增高,铁皮石斛组培苗的鲜质量、株高、根数、叶绿素含量基本呈递增的趋势,分蘖数呈递减的趋势,硝酸铈浓度为40 mg/L时,其鲜质量、根数、株高最大,分蘖数最少;铁皮石斛移栽培养30 d后,稀土元素组比空白组中的存活率和抽芽率高,硝酸铈为40 mg/L时其生长情况最佳;一定浓度的稀土元素La 、Ce能增强铁皮石斛组培苗的T-SOD酶、CAT酶活性和根系活力,添加10.0～40.0 mg/L La3+,SOD酶活性和CAT酶活性均呈现先增后降的趋势;添加10.0～40.0 mg/L Ce3+,SOD酶活性逐渐增强,但CAT酶活性在Ce3+10～ 30.0 mg/L时逐渐增强,40.0 mg/L时又稍下降;添加10.0～40.0 mg/L La3+,根系活力呈先增后降的趋势,10～ 30.0mg/L时根系活力逐渐上升,40.0 mg/L时略有下降;添加10.0～40.0 mg/L Ce3+,根系活力逐渐上升,40.0mg/L时最高.结论 稀土元素镧、铈对铁皮石斛组培苗的生长及T-SOD酶、CAT酶活性和根系活力均有较显著的影响,本文结果为铁皮石斛组培苗的壮苗以及品质的提高提供了依据.     

Vc稀土在猪,鸡,鱼体内的分布及残留量的观察

用“三溴偶氮坤分光光度法”检测猪、鸡,鱼体内稀土元素的含量,结果正常饲料组体内均存在微量稀土元素。而喂饲Vc稀土组的猪(mg/kg,140天)、鸡(30PPm,398天)、鱼(34～40mg/kg,150天)体内稀土主要分布在骨,肝、脾、肺、胃等脏器组织中,猪脏器组织中稀土残留量为0.58mg/kg,鸡脏器中为0.13mg/kg,鱼脏器中为0.25mg/kg。而猪肉中未检出,鸡肉为0.0O5mg/kg,鱼肉除团头鲂0.24mg/kg外,其它如鲫鱼、罗非鱼、草鱼等的肉中稀土含量均与对照组相近。说明可食的肉类部分无明显残留。作者认为在此喂饲条件下的商品猪、鸡和鱼肉,人是可以食用的。     

混合氨基酸稀土配合物的胚胎毒性研究

在孕鼠“致畸敏感期”分别给予农药混合氨基酸稀土配合物（简称ＭＡＲ）１４２８、７１４、３５７ｍｇ／ｋｇ。１４２８ｍｍ／ｋｍ组胎鼠体重、身长、骨化程度和孕鼠体重增值显著降低，胚胎吸收和胎鼠死亡则增高。提示该剂量ＭＡＲ具有明显胚胎毒性。７１４、３５７ｍｇ／ｋｇ剂量组各项指标与对照组比较则无统计差异。     

Rare-earch elements in urinary calculi

Summary In vitro studies have demonstrated that trace elements have inhibitory as well as stimulatory effects on the crystallization of urinary stones. Little is known about the activities of rare-earth elements (REEs) in the human body. Although their physiological role is unclear, an effect on calcium transport mechanisms is discussed. In the present study, ten kidney stones (six oxalate and four phosphate stones) were analyzed by neutron-activation analysis for their REE patterns. Urinary stones are capable of concentrating these elements, and some fractionation into light and heavy REEs appears to take place during deposition. Significantly elevated concentrations of heavy REEs such as europium, terbium, and lutetium were detected in phosphate stones as compared with oxalate stones (P<0.005).     

稀土暴露对人体免疫功能的影响

目的　探讨稀土暴露对人体免疫系统功能的影响。方法　运用电感藕合等离子体 质谱法对 10 2例稀土暴露区居民和 5 8例对照区居民 (均为成人 )血稀土含量进行测定 ,并分别用流式细胞术和免疫比浊法对研究对象的细胞免疫和体液免疫功能进行测定。结果　稀土暴露组血稀土含量明显高于对照组 ;稀土暴露组细胞免疫和体液免疫功能发生明显变化 (P <0 .0 5或P <0 .0 1)。多元逐步回归分析表明血稀土总含量是导致上述免疫学指标发生变化的重要因素之一。结论　稀土暴露对人体细胞免疫功能和体液免疫功能均有一定的影响作用 ,从而推论稀土暴露对人体的免疫系统功能有一定促进作用     

吸入钍尘对矿工肝功能影响是否存在阈值的研究

目的 对长期吸入含钍稀土矿尘的矿工肺内钍的沉积量与肝功能5项指标之间是否存在阈值进行了初步研究。方法 用高灵敏度负高压人呼出气中钍射气子体收集测量系统对每名被检矿工测定其肺内钍的沉积量。结果 研究发现,当接尘矿工肺内钍的沉积量不超过7.26Bq,其肝功能5项指标不会出现异常。结论 结合国外文献报道,作者认为长期吸入含钍稀土矿尘矿工肺内钍沉积量与肝功能5项指标之间存在的阈值,可能在7.26Bq至74Bq之间。     

Postweaning exposure to lanthanum alters neurological behavior during early adulthood in rats

Lanthanum is a rare-earth element that has been used in various fields including medicine, agriculture and industry. Previously, in utero lanthanum exposure to dams was shown to alter neurobehavior and neurotransmitter levels in rat offspring; however, the effects of postweaning exposure to lanthanum on neurological behavior is still limited. The purpose of this study was to investigate the effects of postweaning exposure to lanthanum on neurological behavior during early adulthood in rats. Rats were orally exposed to 0, 2, 20, 60 mg/kg BW of lanthanum nitrate from postnatal day (PND) 24 to PND60. Our results indicated that lanthanum treatment significantly decreased body weight and food intake. Morris water maze test results showed that lanthanum significantly decreased escape latency and travel distance. Lanthanum treatment also significantly decreased grip strength, hindlimb strength, and running time & distance in motor activity test. Further results showed that lanthanum treatment significantly decreased plasma neurotransmitter levels of acetylcholine and norepinephrine as well as the number of neurons in the CA1 area of the hippocampus. These results suggest that postweaning exposure to lanthanum have adverse effects on neurobehaviors and the central nervous system, with no-observed-adverse-effect level at 2 mg/kg BW and benchmark dose lower confidence limit at 1.7 mg/kg BW.     

赣南稀土矿区白血病病例对照研究

目的 探索稀土环境污染与白血病的关系。方法 采用1：1配对的病例对照研究，于2001年11～12月在江西赣南稀土矿区选择经骨髓穿刺检查确诊的白血病患者51例，收集相关的资料进行条件logistic回归分析。结果 多因素分析提示主要的危险因素是：经常饮用河水(OR=5．543)、住家距稀土矿距离及生活年限(OR=3．308)、有机磷农药接触史(OR=3．014)；而经常饮茶(OR=0．164)提示为保护因素。结论 稀土环境暴露史、有机磷农药接触史与当地白血病发病有关，而饮茶对白血病发生具有保护作用，但有待进一步研究。     

稀土元素对甘草愈伤组织生长及黄酮类化合物含量的影响

稀土元素铕对甘草愈伤组织生长和甘草黄酮类化合物合成试验.结果表明,低浓度的稀土元素Eu3 对甘草愈伤组织的生物量积累和黄酮类化合物的生物合成有明显的促进作用.培养基中添加0.1 mg/L的稀土元素Eu3 ,愈伤组织的5种黄酮类化合物含量为对照的2.7倍,甘草素含量更达对照的4倍.