常见中药补剂的毒性与安全问题分析

运用文献综述法分析了口服中药补剂后发生不良反应的原因及防治措施,为中药补剂更好地运用于运     

Purification and characterization of keratinase from a new Bacillus subtilis strain

The aim of this study was to purify and characterize a keratinase produced by a new isolated Bacillus subtilis KD-N2strain. The keratinase produced by the isolate was purified using ammonium sulphate precipitation, Sephadex G-75 and DEAE (diethylaminoethyl)-Sepharose chromatographic techniques. The purified enzyme was shown to have a molecular mass of 30.5kDa, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The optimum pH at 50℃ was 8.5 and the optimum temperature at pH 8.5 was 55℃. The keratinase was partially inactivated by some metal ions, organic solvents and serine protease inhibitor phenylmethanesulfonyl fluoride (PMSF). Sodium dodecyl sulfate (SDS) and ethylene diamine tetraacetic acid (EDTA) had positive effect on the keratinase activity. Reducing agents including dithiothreitol (DTT),mercaptoethanol, L-cysteine, sodium sulphite, as well as chemicals of SDS, ammonium sulfamate and dimethylsulfoxide (DMSO)stimulated the enzyme activity upon a feather meal substrate. Besides feather keratin, the enzyme is active upon the soluble proteins ovalbumin, bovine serum albumin (BSA), casein and insoluble ones as sheep wool and human hair. Calf hair, silk and collagen could not be hydrolyzed by the keratinase.     

Science Letters:Gama-aminobiityric acid accumulation in Elsholtzia splendens in response to copper toxicity

A solution with different Cu supply levels was cultured to investigate gama-aminobutyric acid (GABA) accumulation in Elsholtzia splendens, a native Chinese Cu-tolerant and accumulating plant species. Increasing Cu from 0.25 to 500 μmol/L significantly enhanced levels of GABA and histidine (His), but     

Gama-aminobutyric acid accumulation in Elsholtzia splendens in response to copper toxicity

A solution with different Cu supply levels was cultured to investigate gama-aminobutyric acid (GABA) accumulation in Elsholtzia splendens, a native Chinese Cu-tolerant and accumulating plant species. Increasing Cu from 0.25 to 500 μmol/L significantly enhanced levels of GABA and histidine (His), but considerably decreased levels of aspartate (Asp) and glutamate (Glu) in the leaves. The leaf Asp level negatively correlated with leaf Cu level, while leaf GABA level positively correlated with leaf Cu level. The leaf Glu level negatively correlated with leaf GABA level in Elsholtzia splendens. The depletion of leaf Glu may be related to the enhanced synthesis of leaf GABA under Cu stress.     

湿地内外滇池水体中微囊藻毒素对小鼠生殖毒性的研究

通过提取湿地内外滇池水体水样中的微囊藻毒素,检测湿地内外水体中微囊藻毒素对小鼠的生殖毒性,以及对其体外和体内精子活性的影响.结果表明：湿地外周滇池水体中的微囊藻毒素对小鼠具有生殖毒性,特别在精子的生成和精子活性方面表现出较强的毒性作用;湿地内水体的生殖毒性明显低于湿地外水体,对小鼠的睾丸和附睾不会形成器质性变化,也不会影响精子的数量和精子活性（与对照组比较P〉0.05）.结果证实湿地能有效抑制滇池水体中微囊藻毒素的形成,对滇池水质可起到有效的净化作用.     

滇池微囊藻毒素对小鼠肝脏的毒性研究

为了解滇池微囊藻毒素对小鼠肝脏的损伤作用,提取滇池水华水样中微囊藻毒素对小鼠进行连续灌胃试验,之后取肝组织石蜡包埋、HE染色,观察小鼠肝脏组织显微结构.结果显示：小鼠肝脏充血、肿胀;微囊藻毒素使小鼠肝脏组织的显微结构出现异常变化,肝细胞索结构破坏,肝血窦明显扩张,部分肝细胞胞质溶解、核消失,病灶内有大量炎症细胞浸润.表明微囊藻毒素具有肝毒性,可破坏肝小叶的完整性,抑制肝脏的合成与解毒功能.     

上海市高架道路径流持久性有毒物质研究(英文)

对上海市高架道路17场降雨径流进行收集监测,分析了降雨径流中10种重金属和16种多环芳烃(PAHs)的浓度.结果表明:上海市高架道路径流中10种重金属As,Se,Zn,Pb,Ni,Fe,Mn,Cr,Cu和Al的浓度范围分别为0.50~51.80,0~20.80,13.67~445.80,0~44.20,0~15.80,39.58~264.20,0~253.00,0~8.20,0~124.20,159.83~536.40μg/L.其中,Se,Pb,Mn和Al浓度值超过了其对应的基准连续浓度,而Zn和Cu则超过了其所对应的基准最大浓度.径流中多环芳烃浓度值范围为37.25~114.57ng/L,均低于对应的基准连续浓度.Zn,Cu和PAHs表现出明显的初期冲刷效应.运用改进的内梅罗指数法对径流水质进行评价,发现8场降雨径流样品水质生物毒性极强,4场生物毒性较强,3场生物毒性一般,仅有2场生物毒性较弱.因此,城市高架道路径流对水生态系统具有较高的生态风险,需对其进行净化处理.     

土壤Cd污染的生物修复

Cd污染是我国常见的一种土壤重金属污染.本文总结了土壤中Cd的分布特性、污染状况、存在状态及其对生物的毒害作用,分析了土壤Cd污染的生物修复研究状况,重点评述了Cd污染的植物修复原理、类型与技术及其进展,并结合我国土壤Cd的污染特点和部分研究结果,提出今后的研究目标和方向.     

CuSO4对果蝇的发育毒性与生殖毒性

本实验以模式生物果蝇为实验材料,包括红眼果蝇和白眼果蝇两种不同的品系,以0.05mg/mL、0.1mg/mL、0.5mg/mL、1 mg/mL四个不同浓度梯度的CuSO4染毒组以及空白对照组培养果蝇,以其F1代果蝇的生长发育速度、雌雄比例、亲本的生殖能力作为测量终点,探讨不同浓度的铜离子对果蝇的生长发育的影响.结果表明：1 mg/mL组对卵具有致死效应,在不致死浓度范围内,随着铜离子的浓度增加,果蝇从卵发育为成虫的速度越慢,且生殖能力越低.含有CuSO4的培养基培养的果蝇其F1代果蝇的雌雄比例也高于空白组.可见铜离子对果蝇具有发育毒性和生殖毒性.     

磷酸三(1,3-二氯二丙基)酯(TDCPP)对斑马鱼胚胎急性毒性研究

磷酸三(1,3-二氯二丙基)酯(TDCPP)是环境中广泛存在的新兴持久性有机污染物。实验将受精1 h后的斑马鱼胚胎暴露于TDCPP(0,5μg/L,20μg/L,80μg/L和180μg/L)至受精后168 h,在特定时间点观察并记录胚胎/幼鱼的存活率(24～120 haf)、孵化率与畸形率(72 haf)、心率(48 haf,84 haf)、体重与体长(168 haf)。结果显示:与对照组相比,急性暴露TDCPP使斑马鱼胚胎/幼鱼的存活率与孵化率降低、畸形率增加、心率以及体长受到显著抑制,表明TDCPP对斑马鱼胚胎存在显著的急性毒性,并且这种影响随着暴露液TDCPP浓度的增大更为明显。