Isolation, amino acid sequence and biological activities of novel long-chain polyamine-associated peptide toxins from the sponge Axinyssa aculeata

A novel family of functionalized peptide toxins, aculeines (ACUs), was isolated from the marine sponge Axinyssa aculeate. ACUs are polypeptides with N-terminal residues that are modified by the addition of long-chain polyamines (LCPA). Aculeines were present in the sponge extract as a complex mixture with differing polyamine chain lengths and peptide structures. ACU-A and B, which were purified in this study, share a common polypeptide chain but differ in their N-terminal residue modifications. The amino acid sequence of the polypeptide portion of ACU-A and B was deduced from 3' and 5' RACE, and supported by Edman degradation and mass spectral analysis of peptide fragments. ACU induced convulsions upon intracerebroventricular (i.c.v.) injection in mice, and disrupted neuronal membrane integrity in electrophysiological assays. ACU also lysed erythrocytes with a potency that differed between animal species. Here we describe the isolation, amino acid sequence, and biological activity of this new group of cytotoxic sponge peptides.     

Understanding Interactions of Functionalized Nanoparticles with Proteins: A Case Study on Lactate Dehydrogenase

Nanomaterials in biological solutions are known to interact with proteins and have been documented to affect protein function, such as enzyme activity. Understanding the interactions of nanoparticles with biological components at the molecular level will allow for rational designs of nanomaterials for use in medical technologies. Here we present the first detailed molecular mechanics model of functionalized gold nanoparticle (NP) interacting with an enzyme (l ‐lactate dehydrogenase (LDH) enzyme). Molecular dynamics (MD) simulations of the response of LDH to the NP binding demonstrate that although atomic motions (dynamics) of the main chain exhibit only a minor response to the binding, the dynamics of side chains are significantly constrained in all four active sites that predict alteration in kinetic properties of the enzyme. It is also demonstrated that the 5 nm gold NPs cause a decrease in the maximal velocity of the enzyme reaction (V_max) and a trend towards a reduced affinity (increased K_m) for the β‐NAD binding site, while pyruvate enzyme kinetics (K_m and V_max) are not significantly altered in the presence of the gold NPs. These results demonstrate that modeling of NP:protein interactions can be used to understand alterations in protein function.     

那他霉素的特性及其在食品中的应用

本文介绍了那他霉素的理化特性、抗微生物特性和作用机理；详述了那他霉素在于酪、肉制品、果汁中的应用及研究状况，并就各国的法规状况进行了对比。最后概述了那他霉素的毒理学和分析方法。     

Integrating toxicology into cosmetic ingredient research and development

Toxicity assessment of new cosmetic ingredients is often relegated to the end of the research and development (R&D) cycle. This is an inefficient development scheme, since toxicity concerns often lead to restrictions on the type of cosmetic applications the ingredient can go into and can even lead to abandoning the ingredient. This paper presents a tiered approach for integrating toxicology into cosmetic ingredient R&D. The tiered approach is flexible allowing a company to make cost-efficient use of readily available resources. Integrating toxicity assessment of new cosmetic ingredients early in the R&D cycle would help avoid developing ingredients with limited or no market potential due to toxicity concerns.     

食品毒理学数据库构建研究

目的 建立食品毒理学数据库（FoodTox）。方法 建立食品毒理学数据库网站,确定数据库优先入库名单,通过文献检索的方式收集相关物质的毒理学资料,利用系统文献综述（SLR）方法整理入库物质的毒理学数据。结果 食品毒理学数据库已收录1 600余种物质,相关数据包括代谢、急性毒性、遗传毒性、生殖发育毒性、亚慢性毒性、慢性毒性和致癌、人群资料、健康指导值等毒理学资料和国内外管理法规、相关食物和症状等,已经向相关领域工作者开放使用。结论 本数据库的建立将为食品毒理学工作者提供第一手的参考资料,为相关优先物质的毒理学安全性评价提供依据,为应急风险评估提供技术支持。     

Effective Regulatory Approval Process for Food Ingredient Technologies

Most sciences and technologies related to food safety have advanced exponentially over the 40 years since passage in the U.S. of the Food Additive Amendment of 1958 to the Federal Food, Drug and Cosmetic (FD&C) Act. Effective regulatory decision making places a high premium on competent professional and administrative judgement applied to sound scientific data. This review discusses changes and lessons learned in the food safety sciences over the last 4 decades. Other segments of the safety and compliance infrastructure necessary to assure that the public receives safe and wholesome foods have not kept pace with the new scientific knowledge. The quality of foods in our marketplace can be improved only after the regulatory and legislative segments of the infrastructure, discussed in a companion symposium paper,⁸ are brought into better synchrony with the sciences.     

蒸汽爆破法预处理制取的灵芝粗提物安全性评价初步研究

通过比较蒸汽爆破预处理前后灵芝制取的灵芝粗提物中功能性成分的提取率变化来反映蒸汽爆破技术对灵芝提取过程的影响,并对灵芝提取物进行安全性评价初步研究。以灵芝多糖,灵芝三萜提取率的变化来反映蒸汽爆破技术对灵芝粗提物的影响,采用急性毒性实验,30d饲养实验进行安全性初步评价。结果表明:1.5MPa,150s灵芝蒸汽爆处理后的多糖提取率是3h未处理组的10倍,蒸汽爆破2.1MPa,210s处理后灵芝粗提物中三萜的提取率增加为原来的1.95倍,本次实验初步评估表明蒸汽爆破法预处理制取的灵芝粗提物无明显的毒副作用及不良反应。      

对制浆造纸混合废水的急性毒性测定方法的研究

用白鲢鱼作为受试鱼对制浆造纸混合废水进行了急性毒性的测定研究，分别用概率单位法和直线内插法求出９６ｈ ＬＣ５０，并对影响该测定方法的多种因素进行了分析。     

Size-dependent cytotoxicity of gold nanoparticles

Gold nanoparticles are widely used in biomedical imaging and diagnostic tests. Based on their established use in the laboratory and the chemical stability of Au(0), gold nanoparticles were expected to be safe. The recent literature, however, contains conflicting data regarding the cytotoxicity of gold nanoparticles. Against this background a systematic study of water-soluble gold nanoparticles stabilized by triphenylphosphine derivatives ranging in size from 0.8 to 15 nm is made. The cytotoxicity of these particles in four cell lines representing major functional cell types with barrier and phagocyte function are tested. Connective tissue fibroblasts, epithelial cells, macrophages, and melanoma cells prove most sensitive to gold particles 1.4 nm in size, which results in IC(50) values ranging from 30 to 56 microM depending on the particular 1.4-nm Au compound-cell line combination. In contrast, gold particles 15 nm in size and Tauredon (gold thiomalate) are nontoxic at up to 60-fold and 100-fold higher concentrations, respectively. The cellular response is size dependent, in that 1.4-nm particles cause predominantly rapid cell death by necrosis within 12 h while closely related particles 1.2 nm in diameter effect predominantly programmed cell death by apoptosis.     

Ethical Observations on the Choice of Parenteral Solvents

The parenteral administration of insoluble drugs leads to the use of biologically active solvents inducing effects associated with ethical cause of concern including pain and pharmacological interactions. Selected vehicles currently used were ethically and scientifically reviewed. Our investigations allowed reinforcing the formulation decision tree with an ethical point of view. The last generation of cyclodextrin appears to be the safest solvent. Second choice could be lipidic emulsions, third choice being co-solvents, and finally non-ionic surfactants because of their hypersensitivity reactions. Screening tests including pH, osmolality measurements, cytotoxicity, and hemotoxicity, should allow to check the formulation tolerance before the animals' administration.