Cu^2＋、Cd^2＋和Cr^6＋对孔雀鱼的单一与联合毒性效应

采用静水生物测试法研究了Cu、Cd和Cr等重金属对孔雀鱼的单一与联合毒性效应。单一毒性试验结果表明：暴露时间为24,48,72和96h时,Cu^2＋对孔雀鱼的LC50分别为5．70,4．02,2．95和2．36mg／L,Cd^2＋对孔雀鱼的LC50分别为23．24,20．15,18．07和17．71mg／L,Cr^6＋对孔雀鱼的LC50分别为88．56,65．21,47．81和43．40mg／L。3种重金属离子对孔雀鱼均为高毒性,毒性大小为Cu^2＋〉Cdh〉Cr^6＋。联合毒性试验表明：当浓度比为1：1或1：1：1,Cu^2＋与Cd^2＋、Cu^2＋与Cr6＋、Cd^2＋与Cr^6＋以及Cu^2＋、Cd^2＋与Cr^6＋共存时的联合毒性均为毒性增强的协同作用．     

无毒和低毒防污涂料的研究进展及存在问题

防污涂料作为一个有效解决海生物污损的方法,在船舶、海洋水下设施上得到广泛应用。随着环保意识的增强以及各种相关规定的制订,各国开始竞相研制开发新型无毒和低毒防污涂料。本文在介绍无毒和低毒防污剂、防污涂料的种类、研究现状、应用效果的基础上,论述了从防污剂的筛选到防污涂料实船实验的一系列研制过程以及研制过程中存在的问题,并对未来的发展方向进行了展望。     

天然红色素灵菌红素的急性经口毒性和遗传毒性

灵菌红素属于天然色素,具有离体抑制肿瘤和癌症细胞增殖、抑制微生物生长以及抗疟疾和免疫抑制等功效,具有潜在的巨大应用价值。缺少急性经口毒性和遗传毒性实验的研究限制了灵菌红素在食品工业领域的应用。本研究依据食品安全国家标准进行了灵菌红素的小鼠急性经口毒性实验、哺乳动物红细胞微核实验、小鼠精子畸形实验和细菌回复突变实验。结果表明,灵菌红素急性经口半数致死剂量LD_(50)10 g/kg(以体质量计),3项遗传毒性实验结果为阴性,灵菌红素对小鼠的急性经口毒性属无毒级,对正常细胞无毒,对动物生殖系统没有毒害。     

黄连花茶加工工艺及其抗氧化作用研究

以黄连的花薹为原料,研究了黄连花茶的加工工艺及其抗氧化活性。结果表明,黄连花薹经杀青、冷却后,干燥,包装制得的黄连花茶风味清香、复水性好。采用霍恩氏法,对花茶的急性毒性(LD50)进行测定,21.5g/kg·BW剂量下,实验动物未发现死亡及异常;大于15g/kg·BW剂量,属无毒。水浸出物对羟自由基(·OH)和过氧化氢(H2O2)均具有清除作用。     

罗汉果甜苷的毒性作用研究

目的:研究罗汉果甜苷的毒性作用。方法:　按文献方法用小白鼠进行急性毒性试验,用标准伤寒沙门氏菌做Ames　致突变试验。用家犬进行4周毒性试验。结果:罗汉果甜苷灌胃,对小白鼠的LD50>10000mg/kg,属实际无毒级。Ames　致突变试验结果为阴性。罗汉果甜苷3.0g/kg　(相当于人用量的250倍)　灌胃4周,对家犬的血液学指标、肝、肾、功能、血糖与尿糖以及心、肝、肾、肺、脾的形态学变化均无明显的影响。结论:罗汉果甜苷是一种基本无毒的物质。     

蒙药复方三子汤组分药材川楝子与栀子、诃子配伍前后栀子苷含量的HPLC法测定及其小鼠急性肝毒性研究

建立了蒙药复方三子汤组分药材川楝子、栀子与诃子配伍前后栀子苷含量变化的HPLC分析方法;三子汤组分药材川楝子与栀子、诃子配伍前后小鼠急性肝毒性分析方法。采用Hypersil ODS C18色谱分离柱,以V(乙腈)∶V(水)=15∶85为流动相,流速1 m L/min,检测波长238 nm,HPLC法测定栀子苷含量。小鼠给药,禁食12 h,采血,分离血清,测定血清中谷丙转氨酶(ALT)、碱性磷酸酶(AKP)、天门冬氨酸氨基转移酶(AST)含量。取小鼠肝脏,称重,制成匀浆,离心,取上清液,测定肝匀浆中乳酸脱氢酶(LDH)、碱性磷酸酶(AKP)含量。结果表明,栀子与川楝子、诃子按等质量比配伍后,栀子苷含量均比单味药材栀子中栀子苷含量降低,且对小鼠肝毒性明显降低。因此,三子汤三味药材等质量比配伍,能降低蒙药复方三子汤的毒性。     

Safety Evaluation of Green Tea Polyphenols Consumption in Middle‐aged Ovariectomized Rat Model

This work evaluates chronic safety in middle‐aged ovariectomized rats supplemented with different dosages of green tea polyphenols (GTP) in drinking water. The experiment used 6‐mo‐old sham (n = 39) and ovariectomized (OVX, n = 143) female rats. All sham (n = 39) and 39 of the OVX animals received no GTP treatment and their samples were collected for outcome measures at baseline, 3 mo, and 6 mo (n = 13 per group for each). The remaining OVX animals were randomized into 4 groups receiving 0.15%, 0.5%, 1%, and 1.5% (n = 26 for each) of GTP (wt/vol), respectively, in drinking water for 3 and 6 mo. No mortality or abnormal treatment‐related findings in clinical observations or ophthalmologic examinations were noted. No treatment‐related macroscopic or microscopic findings were noted for animals administered 1.5% GTP supplementation. Throughout the study, there was no difference in the body weight among all OVX groups. In all OVX groups, feed intake and water consumption significantly decreased with GTP dose throughout the study period. At 6 mo, GTP intake did not affect hematology, clinical chemistry, and urinalysis, except for phosphorus and blood urea nitrogen (increased), total cholesterol, lactate dehydrogenase, and urine pH (decreased). This study reveals that the no‐observed‐adverse‐effect level (NOAEL) of GTP is 1.5% (wt/vol) in drinking water, the highest dose used in this study.     

Adsorption of Bisphenol A to a Carbon Nanotube Reduced Its Endocrine Disrupting Effect in Mice Male Offspring

Soluble carbon nanotubes (CNTs) have shown promise as materials for adsorption of environmental contaminants such as Bisphenol A (BPA), due to the high adsorption capacity and strong desorption hysteresis of BPA on CNTs. The adsorption of BPA to CNTs may change the properties of both BPA and CNTs, and induce different toxicity to human and living systems from that of BPA and CNTs alone. Herein, we report that oral exposure of BPA/MWCNT–COOH (carboxylated multi-walled carbon nantubes) adduct to mice during gestation and lactation period decreased the male offspring reproductive toxicity compared with those induced by BPA alone. The adduct decreased malondialdehyde (MDA) level in testis and follicle-stimulating hormone (FSH) in serum, but increased the level of serum testosterone in male offspring in comparison to BPA alone. Our investigations broadened the knowledge of nanotoxicity and provided important information on the safe application of CNTs.     

A Low‐Toxic Multifunctional Nanoplatform Based on Cu9S5@mSiO2 Core‐Shell Nanocomposites: Combining Photothermal‐ and Chemotherapies with Infrared Thermal Imaging for Cancer Treatment

Copper chalcogenides have been demonstrated to be a promising photothermal agent due to their high photothermal conversion efficiency, synthetic simplicity, and low cost. However, the hydrophobic and less biocompatible characteristics associated with their synthetic processes hamper widely biological applications. An alternative strategy for improving hydrophilicity and biocompatibility is to coat the copper chalcogenide nanomaterials with silica shell. Herein, the rational preparation design results in successful coating mesoporous silica (mSiO₂) on as‐synthesized Cu₉S₅ nanocrystals, forming Cu₉S₅@mSiO₂‐PEG core‐shell nanostructures. As‐prepared Cu₉S₅@mSiO₂‐PEG core‐shell nanostructures show low cytotoxicity and excellent blood compatibility, and are effectively employed for photothermal ablation of cancer cells and infrared thermal imaging. Moreover, anticancer drug of doxorubicin (DOX)‐loaded Cu₉S₅@mSiO₂‐PEG core‐shell nanostructures show pH sensitive release profile and are therefore beneficial to delivery of DOX into cancer cells for chemotherapy. Importantly, the combination of photothermal‐ and chemotherapies demonstrates better effects of therapy on cancer treatment than individual therapy approaches in vitro and in vivo.     

Advances in Bioapplications of Carbon Nanotubes

This progress report provides an overview on recent advances in bioapplications of carbon nanotubes including the chemical modification of carbon nanotubes, targeting specifically their covalent and noncovalent conjugations with a variety of biological and bioactive species (proteins and peptides, DNAs/RNAs, and carbohydrates). Furthermore, the significant recent development and progress in the use of carbon nanotubes for biosensors, drug and other delivery systems, bioimaging, etc. and in the understanding of in vivo biodistribution and toxicity of carbon nanotubes are reported.