Arsenic accumulation and speciation in plants from different habitats

This is the postprint version of the article. The published version of the article can be located here: http://www.sciencedirect.com/science/article/pii/S0883292711004914Understanding As accumulation in plants is necessary in order to alleviate problems with As in the environment and to improve sustainable As phytotechnologies. To find suitable candidates for phytoremediation purposes and to investigate specific accumulation patterns due to growth habitat and plant groups, As accumulation in 124 plant species collected from different habitats and speciation in 6 of these plant species, was determined. The data show that submerged plants have a higher accumulation than emergent and terrestrial plants. The As concentration in terrestrial and emergent plants were correlated with the [As]soil, while the accumulation factor correlated negatively with [As]soil. Gymnosperms had a high [As]shoot:[As]root ratio. The inorganic As species, arsenate and arsenite were found in plants from all habitats and methylarsonic acid (MMA) in all but one plant species. Arsenate predominated in submerged plants. The results suggest that the habitat and the [As]soil have a strong influence on the As accumulation in plants and that submerged plants and/or gymnosperms might be suitable for phytoremediation of As

Influence of silicon on arsenic uptake and toxicity in lettuce

Lettuce grown in soil is found to contain high concentrations of arsenic (As). This paper investigates the uptake and speciation of As in lettuce as well as the influenceof silicon (Si) on As uptake, since Si may decrease it. Lettuce plants were cultivated in nutrient solution containing arsenite or arsenate with or without silicate. The uptake and distribution of As between roots and shoots, As accumulation in cell walls, As speciation, and toxic effects on growth were analysed. Results indicate that arsenite was more toxic to lettuce than was arsenate. Silicate decreased arsenate toxicity but had little effect on arsenite toxicity. In contrast, Si decreased arsenite uptake more than arsenate uptake. The concentration of arsenate was higher than that of arsenite in the plants independent of the As species added. When arsenate was added, the As concentration in shoots was half of that in the roots and this distribution did not change with Si addition. When arsenite was added, approximately 10% of As was found in the shoots and 90% in the roots; this pattern changed in the presence of Si, and As became evenly distributed in the plant. In both roots and shoots, approximately 40% of the As was found in the cell wall fraction; when arsenite was added, the presence of Si increased this fraction to 47%, but only in the shoots. The extraction efficiency when analysing the As species was lower in shoots than in roots, especially in the presence of arsenite and Si. The opposite was found for As concentration in pellets after extraction. This indicated variation in the binding strength of arsenite and arsenate between roots and shoots and between Si- and non-Si-treated plants

Quantification of Normal Cell Fraction and Copy Number Neutral LOH in Clinical Lung Cancer Samples Using SNP Array Data

Technologies based on DNA microarrays have the potential to provide detailed information on genomic aberrations in tumor cells. In practice a major obstacle for quantitative detection of aberrations is the heterogeneity of clinical tumor tissue. Since tumor tissue invariably contains genetically normal stromal cells, this may lead to a failure to detect aberrations in the tumor cells.Using SNP array data from 44 non-small cell lung cancer samples we have developed a bioinformatic algorithm that accurately models the fractions of normal and tumor cells in clinical tumor samples. The proportion of normal cells in combination with SNP array data can be used to detect and quantify copy number neutral loss-of-heterozygosity (CNNLOH) in the tumor cells both in crude tumor tissue and in samples enriched for tumor cells by laser capture microdissection.Genome-wide quantitative analysis of CNNLOH using the CNNLOH Quantifier method can help to identify recurrent aberrations contributing to tumor development in clinical tumor samples. In addition, SNP-array based analysis of CNNLOH may become important for detection of aberrations that can be used for diagnostic and prognostic purposes

A plan for a joint study into the impacts of AI on professional competencies of IT professionals and implications for computing students.

As Artificial Intelligence (AI) continues to make its presence felt in transforming workplaces around the world, and the Information Technology industry in particular, it is essential to understand its impact on the work practices of IT professionals, and the implications for computing students and curricula. This research project builds on work initiated jointly, in Sweden, New Zealand and Scotland, investigating concerns about the increasing impacts of Artificial Intelligence in IT Sector workplaces for employee work engagement and the implications for tertiary study, assessment and curricula in computing. "Work engagement", has been defined as the positive inner state where employees are fully present and engaged in their work, and is closely linked to motivation, learning, productivity, and accountability. Within the context of (Generative) AI at work, IT professionals have been noted as early adopters of AI. Their involvement in implementing and utilising AI technologies can provide valuable insights into the interplay between AI and work engagement. The implications for students are significant as future IT professionals, who must acquire and enhance competencies to adapt and thrive in digital workplaces

Phase II randomized study of the IGF-1R pathway modulator AXL1717 compared to docetaxel in patients with previously treated, locally advanced or metastatic non-small cell lung cancer

Background: The primary objective of this study was to compare the progression-free survival (PFS) at 12 weeks between patients treated with IGF-1R pathway modulator AXL1717 (AXL) and patients treated with docetaxel (DCT). Material and methods: The study was conducted at 19 study centers in five countries. A total of 99 patients with previously treated, locally advanced or metastatic non-small cell lung cancer (NSCLC) of the squamous cell carcinoma (SCC) or adenocarcinoma (AC) subtypes in need of additional treatment were randomized and treated with either 300 or 400 mg of AXL as daily BID treatment (58 patients) or DCT given as 75 mg/m2 in three-week cycles (41 patients) as monotherapy in a 3:2 ratio for each NSCLC subtype. Patients were treated in the primary study treatment period for a maximum of four treatment cycles. Results: The 12-week PFS rate, median PFS and overall survival (OS), as well Kaplan-Meier hazard ratio for PFS and OS, did not show any statistically significant differences between the treatment groups. For the primary endpoint, the AXL group had a lower percentage of patients (25.9%) who were progression-free at Week 12 as compared to the DCT group (39.0%), although the difference was not statistically significant. The most notable difference in the incidence of treatment emergent adverse effects (TEAEs) was the lower incidence of treatment-related grade 3/4 neutropenia in patients treated with AXL. Conclusion: These results suggest neither of the treatments to be superior of the other when treating locally advanced or metastatic NSCLC. Considering the lower incidence of grade 3/4 neutropenia in the AXL group this treatment warrants further research

Grapevine Yield and Leaf Area Estimation Using Supervised Classification Methodology on RGB Images Taken under Field Conditions

The aim of this research was to implement a methodology through the generation of a supervised classifier based on the Mahalanobis distance to characterize the grapevine canopy and assess leaf area and yield using RGB images. The method automatically processes sets of images, and calculates the areas (number of pixels) corresponding to seven different classes (Grapes, Wood, Background, and four classes of Leaf, of increasing leaf age). Each one is initialized by the user, who selects a set of representative pixels for every class in order to induce the clustering around them. The proposed methodology was evaluated with 70 grapevine (V. vinifera L. cv. Tempranillo) images, acquired in a commercial vineyard located in La Rioja (Spain), after several defoliation and de-fruiting events on 10 vines, with a conventional RGB camera and no artificial illumination. The segmentation results showed a performance of 92% for leaves and 98% for clusters, and allowed to assess the grapevine’s leaf area and yield with R2 values of 0.81 (p < 0.001) and 0.73 (p = 0.002), respectively. This methodology, which operates with a simple image acquisition setup and guarantees the right number and kind of pixel classes, has shown to be suitable and robust enough to provide valuable information for vineyard management

Quantitative real-time RT-PCR and chromogenic in situ hybridization: precise methods to detect HER-2 status in breast carcinoma

<p>Abstract</p> <p>Background</p> <p><it>HER-2 </it>gene testing has become an integral part of breast cancer patient diagnosis. The most commonly used assay in the clinical setting for evaluating HER-2 status is immunohistochemistry (IHC) and fluorescence <it>in situ </it>hybridization (FISH). These procedures permit correlation between <it>HER-2 </it>expression and morphological features. However, FISH signals are labile and fade over time, making post-revision of the tumor difficult. CISH (chromogenic <it>in situ </it>hybridization) is an alternative procedure, with certain advantages, although still limited as a diagnostic tool in breast carcinomas.</p> <p>Methods</p> <p>To elucidate the molecular profile of HER-2 status, mRNA and protein expression in 75 invasive breast carcinomas were analyzed by real time quantitative RT-PCR (qRT-PCR) and IHC, respectively. Amplifications were evaluated in 43 of these cases by CISH and in 11 by FISH.</p> <p>Results</p> <p>The concordance rate between IHC and qRT-PCR results was 78.9%, and 94.6% for qRT-PCR and CISH. Intratumoral heterogeneity of <it>HER-2 </it>status was identified in three cases by CISH. The results of the three procedures were compared and showed a concordance rate of 83.8%; higher discordances were observed in 0 or 1+ immunostaining cases, which showed high-level amplification (15.4%) and <it>HER-2 </it>transcript overexpression (20%). Moreover, 2+ immunostaining cases presented nonamplified status (50%) by CISH and <it>HER-2 </it>downexpression (38.5%) by qRT-PCR. In general, concordance occurred between qRT-PCR and CISH results. A high concordance was observed between CISH/qRT-PCR and FISH. Comparisons with clinicopathological data revealed a significant association between <it>HER-2 </it>downexpression and the involvement of less than four lymph nodes (<it>P </it>= 0.0350).</p> <p>Conclusion</p> <p>Based on these findings, qRT-PCR was more precise and reproducible than IHC. Furthermore, CISH was revealed as an alternative and useful procedure for investigating amplifications involving the <it>HER-2 </it>gene.</p