The current state of GMO governance: Are we ready for GM animals?

Given the history of GMO conflict and debate, the GM animal future is dependent on the response of the regulatory landscape and its associated range of interest groups at national, regional and international levels. Focusing on the EU and the USA, this article examines the likely form of that multi-level response, the increased role of cultural values, the contribution of new and existing interest groups and the consequent implications for the commercialization of both green and red GM animal biotechnology.     

实时荧光定量PCR方法快速检测转基因大豆

针对转基因大豆中普遍含有的35S启动子进行引物设计,以双链DNA染料SYBR GreenⅠ为荧光标记物,利用实时荧光定量PCR方法对大豆样品进行检测。该法检测转基因大豆的检测低限为0.005 nmol/L的35S启动子,线性范围达3个数量级,可快速区分转基因大豆和非转基因大豆,具有快速、简便、灵敏、安全、高通量、低成本等优点,可推广用于转基因植物产品的快速定量检测。     

转基因动物生物安全研究与评价

随着转基因动物在新品种培育、异种器官移植、生物反应器和疾病模型等方面的研究与发展,转基因动物的生物安全性引起了人们的广泛关注。目前,各国政府与机构已制定了相应的法律法规来规范转基因动物的研究与应用。文中介绍了转基因动物生物安全研究的内容、评价原则、评价政策与程序、上市或有望上市的转基因动物产品。最后,对转基因动物及其产品的研究与应用进行了展望。     

Novel self-associative and multiphasic nanostructured soft carriers based on amphiphilic hyaluronic acid derivatives

The purpose of the present study was to investigate the physicochemical properties in aqueous media of amphiphilic hyaluronic acid (HA) derivatives obtained by reaction of HA's hydroxyl groups with octenyl succinic anhydride (OSA). The self-associative properties of the resulting octenyl succinic anhydride-modified hyaluronic acid (OSA-HA) derivatives were studied by fluorescence spectroscopy using Nile Red as fluorophore. The morphology, size and surface charge of the OSA-HA assemblies were determined by transmission electron microscopy, dynamic light scattering and by measuring their electrophoretic mobility, respectively. OSA-HA was shown to spontaneously self-associate in aqueous media into negatively charged spherical and multiphasic nanostructures with a hydrodynamic diameter between 170 and 230 nm and to solubilize hydrophobic compounds such as Nile Red. This was a good indication that OSA-HA could be used as building block for the formulation of soft nanocarriers towards the encapsulation and controlled delivery of hydrophobic active ingredients or drugs.     

Copper export from cultured astrocytes

Copper is an essential trace metal that is required as a catalytic co-factor or a structural component of several important enzymes. However, since excess of copper can also harm cells due to its potential to catalyse the generation of toxic reactive oxygen species, transport of copper and the cellular copper content are tightly regulated. Astrocytes are known to efficiently take up copper ions, but it was not known whether these cells are also able to export copper. Treatment of astrocyte-rich primary cultures for 24 h with copper chloride caused a concentration-dependent increase in the specific cellular copper content. During further 24 h incubation in the absence of copper chloride, the copper-loaded astrocytes remained viable and released up to 45% of the accumulated copper. The rate of copper export was proportional to the amount of cellular copper, was almost completely prevented by lowering the incubation temperature to 4 °C and was partly prevented by the endocytosis inhibitor amiloride. Copper export is most likely mediated by the copper ATPase ATP7A, since this transporter is expressed in astrocyte cultures and its cellular location is strongly affected by the absence or the presence of extracellular copper. The potential of cultured astrocytes to export copper suggests that astrocytes provide neighbouring cells in brain with this essential trace element.     

Fungal soil communities in a young transgenic poplar plantation form a rich reservoir for fungal root communities

Fungal communities play a key role in ecosystem functioning. However, only little is known about their composition in plant roots and the soil of biomass plantations. The goal of this study was to analyze fungal biodiversity in their belowground habitats and to gain information on the strategies by which ectomycorrhizal (ECM) fungi form colonies. In a 2-year-old plantation, fungal communities in the soil and roots of three different poplar genotypes (Populus × canescens, wildtype and two transgenic lines with suppressed cinnamyl alcohol dehydrogenase activity) were analyzed by 454 pyrosequencing targeting the rDNA internal transcribed spacer 1 (ITS) region. The results were compared with the dynamics of the root-associated ECM community studied by morphotyping/Sanger sequencing in two subsequent years. Fungal species and family richness in the soil were surprisingly high in this simple plantation ecosystem, with 5944 operational taxonomic units (OTUs) and 186 described fungal families. These findings indicate the importance that fungal species are already available for colonization of plant roots (2399 OTUs and 115 families). The transgenic modification of poplar plants had no influence on fungal root or soil communities. Fungal families and OTUs were more evenly distributed in the soil than in roots, probably as a result of soil plowing before the establishment of the plantation. Saprophytic, pathogenic, and endophytic fungi were the dominating groups in soil, whereas ECMs were dominant in roots (87%). Arbuscular mycorrhizal diversity was higher in soil than in roots. Species richness of the root-associated ECM community, which was low compared with ECM fungi detected by 454 analyses, increased after 1 year. This increase was mainly caused by ECM fungal species already traced in the preceding year in roots. This result supports the priority concept that ECMs present on roots have a competitive advantage over soil-localized ECM fungi.     

Role of recent and old riverine barriers in fine-scale population genetic structure of Geoffroy's tamarin (Saguinus geoffroyi) in the Panama Canal watershed

The role of physical barriers in promoting population divergence and genetic structuring is well known. While it is well established that animals can show genetic structuring at small spatial scales, less well-resolved is how the timing of the appearance of barriers affects population structure. This study uses the Panama Canal watershed as a test of the effects of old and recent riverine barriers in creating population structure in Saguinus geoffroyi, a small cooperatively breeding Neotropical primate. Mitochondrial sequences and microsatellite genotypes from three sampling localities revealed genetic structure across the Chagres River and the Panama Canal, suggesting that both waterways act as barriers to gene flow. F-statistics and exact tests of population differentiation suggest population structure on either side of both riverine barriers. Genetic differentiation across the Canal, however, was less than observed across the Chagres. Accordingly, Bayesian clustering algorithms detected between two and three populations, with localities across the older Chagres River always assigned as distinct populations. While conclusions represent a preliminary assessment of genetic structure of S. geoffroyi, this study adds to the evidence indicating that riverine barriers create genetic structure across a wide variety of taxa in the Panama Canal watershed and highlights the potential of this study area for discerning modern from historical influences on observed patterns of population genetic structure.     

Occurrence of Cronobacter spp. in retail foods

Aims: To study the occurrence of Cronobacter spp. in foods and to investigate the phenotypic properties of the strains isolated. Methods and Results: A total of 53 strains of Cronobacter spp. isolated from 399 food samples were identified using conventional biochemical methods and MALDI‐TOF mass spectrometry. Foods of plant origin were the most frequently contaminated samples. No Cronobacter spp. were found in infant milk formula, wheat‐based infant food, pasteurized and raw cow milk, mincemeat, chicken, chickpea and potato dumpling powder. The individual species were identified as Cronobacter sakazakii (54·7%), Cronobacter malonaticus (28·4%), Cronobacter dublinensis (7·5%), Cronobacter muytjensii (7·5%) and Cronobacter turicensis (1·9%). Cronobacter sakazakii and C. malonaticus belong to biotype 1, 2, 2a, 3, 4 and 5, 5a, respectively. Cronobacter dublinensis strains were subdivided into biotypes 6 and 12. All strains were resistant to erythromycin and two of them were resistant to both erythromycin and tetracycline. Conclusions: Cronobacter spp. were isolated from various food samples pre‐eminently of plant origin and dried food ingredients. Significance and Impact of the Study: These findings will increase and detail our knowledge of the presence and diversity of Cronobacter spp. in foods.     

Tolerance to fermentation products in sugar reception: gustatory adaptation of adult butterfly proboscis for feeding on rotting foods

Adult Vanessa indica and Argyreus hyperbius frequently forage on flower nectar, but the former also utilizes tree sap and rotting fruits. Compared to flower nectar, these rotting foods are characterized by low sugar concentrations and the presence of fermentation products (ethanol and acetic acid). We suspected that gustatory responses by the receptors on the proboscis might differ in these species. Among the three sugars tested, sucrose elicited the greatest probing (behavioral) responses and was followed by fructose and glucose. A. hyperbius showed higher sugar sensitivity than V. indica in probing responsiveness. In electrophysiological responses of the proboscis sensilla, V. indica was slightly more sensitive than A. hyperbius to glucose and lower concentrations of the other sugars. The sugar reception in A. hyperbius was strongly inhibited by fermentation products, particularly acetic acid at natural concentrations. In contrast, V. indica was noticeably less susceptible to them than A. hyperbius, and its behavioral and sensory responses to sucrose were enhanced by 5-20% (w/v) ethanol. Thus, V. indica not only possesses tolerance to fermentation products but may perceive them as synergists for sugar reception. To utilize rotting foods, such tolerance might be more necessary than high sugar sensitivity.