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Soil plays a central role in the functioning of all terrestrial ecosystems. Among the many ecosystem services to which soil contributes are: purification and storage of water, sequestration of organic matter, nutrient cycling for plant growth, and conservation of healthy faunal and microbial populations. As such, soil quality is a key determinant of land reclamation success. Exploitation of the Athabasca oil sands deposit represents a massive land disturbance in Alberta. To date, over 600 km2 of land has been disturbed by oil sands extraction. Following surface mining, reclamation efforts involve the reconstruction of entire landforms. Salvaged surface soils and near-surface geological materials are placed as a new soil cover on the reconstructed landscapes. The goal of reclamation in Alberta is to achieve land capability equivalent to that which existed prior to disturbance. Soil parameters that are currently used to examine reclamation success include chemical and physical attributes known to limit plant growth. Although it is essential to the functioning of these reconstructed ecosystems, soil biology is not yet included as part of the assessment. This project characterized for the first time the biodiversity of soil microfaunal and mesofaunal populations on natural Athabasca oil sands sites. Specifically, we focused on soil protists and micro-invertebrates, as these largely bacteria-consuming organisms are responsible for much of the nutrient fluxes through the soil food web and have crucial bottom-up impact on animal and plant biodiversity. The report addressed two issues. The first is to pilot the use of Next-Generation Sequencing (NGS) technology to establish an assessment of soil protist and invertebrate biodiversity in undisturbed soils as a starting point to identify bioindicators for future assessments of reclamation success. The second question was to assess the relative merits of using paired end 250 versus paired end 300 kits in the NGS protocol, as a technical note going forward. We found that, for these samples, the paired end 250 kits and the protocols in place to use them were reliable and produced consistent datasets and were sufficient to capture the diversity within our samples. Therefore, the additional cost of the paired end 300 kit was not warranted for our needs and would not be adopted in future NGS studies for these organisms in this particular environment. This first assessment of soil protist biodiversity revealed similar trends to those seen from other NGS studies of soils, with cercozoans and ciliates as obvious components of the biodiversity. Further quantitative analysis is key to making any statements about the numerical abundance of any taxa in our samples. However, there are no obviously comparable samples available, with the closest analysis of boreal forest soil being performed with key differences in NGS technology, and the closest technically comparable sample coming from conifer soils in the southern USA. Although we have made as relevant comparisons as possible, to our knowledge this represents the first report of microbial eukaryotic biodiversity of undisturbed soil in the Athabasca region and is an important first step in assessing downstream efforts for soil reclamation and revegetation.

Background: The incidence of ovarian cancer has been increasing worldwide and it is currently the leading cause of death from gynaecological malignancy. Unlike breast cancer, the prognostic role of the human epidermal growth factor receptor-2 (HER-2) in ovarian carcinoma remains controversial. Methods: The aim of this preclinical study was to further characterise the biological, molecular and cellular effects of trastuzumab (Herceptin) using NIH-OVCAR-3 and derived cell lines both in vitro and in vivo. Results: In vitro assessments have shown that trastuzumab treatment inhibited total and phosphorylated HER-2. This was associated with inhibition of the phosphorylated form of phosphatase and tensin homologue (PTEN), mitogen-activated protein kinase and AKT, and the total level of p27kip. Inhibition of PTEN is associated with phosphorylated MEK1/2 upregulation, suggesting a specific inhibition of the protein phosphatase function of PTEN. Moreover, trastuzumab induced the upregulation of RhoB. These molecular modifications promote inhibition of cell migration and potentially restoration of tumour cell contact inhibition. RhoB induction in NIH-OVCAR-3 control cell lines mimics the molecular and cellular trastuzumab long-time exposition effects. RhoB inhibition in NIH-OVCAR-3 long-time exposed to trastuzumab cell line reverses the cellular and molecular effects observed in this model. In vivo examinations have shown that these changes are also associated with the restoration of structural, morphological and normal functions of the peritoneum of an ovarian carcinoma mouse model. Conclusion: These results provide an indication of the mechanisms underlying the anti-tumour activity of trastuzumab that strongly implicate RhoB in an ovarian carcinoma model that does not show HER-2 amplification or overexpression. These findings highlight that trastuzumab effects involve a possible cross-talk between RhoB and PTEN in the early stages of tumour re-growth in a model of micrometastatic ovarian cancer.

Wheat (Triticum aestivum L.) cultivars may have differential effects on soil microbial communities and the breadmaking quality of harvested grain. We compared six Canadian spring wheat cultivars under organic and conventional management systems for yield, breadmaking quality and soil phospholipid fatty acid analysis (PLFA) profile. Yields were lower, but protein levels were higher in the organic system. Cultivars differed for quality traits, but all cultivars had acceptable levels for processing. There were small differences in PLFA profiles for cultivars in the conventional system, but none in the organic system. More significant correlations between grain quality and PLFA measures were present in the organic system. Protein levels and breadmaking quality at least equal to conventional systems can be achieved in organic systems. Wheat cultivars differed for grain quality in both organic and conventional systems, and culivars altered the soil microbial profile in conventional systems. Microbes may play a greater role in determining crop quality in organic systems than in conventional systems.

cited By 76; International audience; (Chemical Equation Presented) Versatile chiral substrates for asymmetric synthesis are formed through the spiroketalization of phenols with a chiral substituted ethanol unit O-tethered to the ortho position upon treatment with PhI-(OAc)2 (see example; TFE = 2,2,2-tri-fluoroethanol). Intermediates with a six-membered iodine(III)-containing ring (the natural localized molecular orbitals associated with the I-C6 bond are shown) undergo ligand coupling to give the spiroketals. © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.