Breeding for improved nitrogen use efficiency in oilseed rape

Oilseed rape has a high requirement for nitrogen (N) fertiliser relative to its seed yield. This paper uses published and unpublished work to explore the extent to which the N use efficiency (seed yield ÷ N supply) of oilseed rape could be improved without reducing seed yield. It was estimated that if the concentration of N in the stem and pod wall at crop maturity could be reduced from 1.0 to 0.6%, the root length density increased to 1 cm/cm3 to 100 cm soil depth and the post flowering N uptake increased by 20 kg N/ha then the fertiliser requirement could be reduced from 191 to 142 kg N/ha and the N use efficiency could be increased from 15.2 to 22.4 kg of seed dry matter per kg N. Genetic variation was found for all of the traits that were estimated to be important for N use efficiency. This indicates that there is significant scope for plant breeders to reduce N use efficiency in oilseed rape

A novel application of motion analysis for detecting stress responses in embryos at different stages of development.

Motion analysis is one of the tools available to biologists to extract biologically relevant information from image datasets and has been applied to a diverse range of organisms. The application of motion analysis during early development presents a challenge, as embryos often exhibit complex, subtle and diverse movement patterns. A method of motion analysis able to holistically quantify complex embryonic movements could be a powerful tool for fields such as toxicology and developmental biology to investigate whole organism stress responses. Here we assessed whether motion analysis could be used to distinguish the effects of stressors on three early developmental stages of each of three species: (i) the zebrafish Danio rerio (stages 19 h, 21.5 h and 33 h exposed to 1.5% ethanol and a salinity of 5); (ii) the African clawed toad Xenopus laevis (stages 24, 32 and 34 exposed to a salinity of 20); and iii) the pond snail Radix balthica (stages E3, E4, E6, E9 and E11 exposed to salinities of 5, 10 and 15). Image sequences were analysed using Sparse Optic Flow and the resultant frame-to-frame motion parameters were analysed using Discrete Fourier Transform to quantify the distribution of energy at different frequencies. This spectral frequency dataset was then used to construct a Bray-Curtis similarity matrix and differences in movement patterns between embryos in this matrix were tested for using ANOSIM

Benign mammary epithelial cells enhance the transformed phenotype of human breast cancer cells

<p>Abstract</p> <p>Background</p> <p>Recent research has yielded a wealth of data underscoring the key role of the cancer microenvironment, especially immune and stromal cells, in the progression of cancer and the development of metastases. However, the role of adjacent benign epithelial cells, which provide initial cell-cell contacts with cancer cells, in tumor progression has not been thoroughly examined. In this report we addressed the question whether benign MECs alter the transformed phenotype of human breast cancer cells.</p> <p>Methods</p> <p>We used both <it>in vitro </it>and <it>in vivo </it>co-cultivation approaches, whereby we mixed GFP-tagged MCF-10A cells (G2B-10A), as a model of benign mammary epithelial cells (MECs), and RFP-tagged MDA-MB-231-TIAS cells (R2-T1AS), as a model of breast cancer cells.</p> <p>Results</p> <p>The <it>in vitro </it>studies showed that G2B-10A cells increase the colony formation of R2-T1AS cells in both soft agar and clonogenicity assays. Conditioned media derived from G2B-10A cells enhanced colony formation of R2-T1AS cells, whereas prior paraformaldehyde (PFA) fixation of G2B-10A cells abrogated this enhancement effect. Moreover, two other models of benign MECs, MCF-12A and HuMECs, also enhanced R2-T1AS colony growth in soft agar and clonogenicity assays. These data reveal that factors secreted by benign MECs are responsible for the observed enhancement of the R2-T1AS transformed phenotype. To determine whether G2B-10A cells enhance the tumorigenic growth of co-injected R2-T1AS cells <it>in vivo</it>, we used the nude mouse xenograft assay. Co-injecting R2-T1AS cells with G2B-10A cells ± PFA-fixation, revealed that G2B-10A cells promoted a ~3-fold increase in tumor growth, irrespective of PFA pre-treatment. These results indicate that soluble factors secreted by G2B-10A cells play a less important role in promoting R2-T1AS tumorigenesis <it>in vivo</it>, and that additional components are operative in the nude mouse xenograft assay. Finally, using array analysis, we found that both live and PFA-fixed G2B-10A cells induced R2-T1AS cells to secrete specific cytokines (IL-6 and GM-CSF), suggesting that cell-cell contact activates R2-T1AS cells.</p> <p>Conclusions</p> <p>Taken together, these data shift our understanding of adjacent benign epithelial cells in the cancer process, from passive, noncontributory cells to an active and tumor-promoting vicinal cell population that may have significant effects early, when benign cells outnumber malignant cells.</p

Combined effect of CCND1 and COMT polymorphisms and increased breast cancer risk

<p>Abstract</p> <p>Background</p> <p>Estrogens are crucial tumorigenic hormones, which impact the cell growth and proliferation during breast cancer development. Estrogens are metabolized by a series of enzymes including COMT, which converts catechol estrogens into biologically non-hazardous methoxyestrogens. Several studies have also shown the relationship between estrogen and cell cycle progression through activation of CCND1 transcription.</p> <p>Methods</p> <p>In this study, we have investigated the independent and the combined effects of commonly occurring CCND1 (Pro241Pro, A870G) and COMT (Met108/158Val) polymorphisms to breast cancer risk in two independent Caucasian populations from Ontario (1228 breast cancer cases and 719 population controls) and Finland (728 breast cancer cases and 687 population controls). Both COMT and CCND1 polymorphisms have been previously shown to impact on the enzymatic activity of the coded proteins.</p> <p>Results</p> <p>Here, we have shown that the high enzymatic activity genotype of CCND1^High(AA) was associated with increased breast cancer risk in both the Ontario [OR: 1.3, 95%CI (1.0–1.69)] and the Finland sample [OR: 1.4, 95%CI (1.01–1.84)]. The heterozygous COMT^Medium(MetVal) and the high enzymatic activity of COMT^High(ValVal) genotype was also associated with breast cancer risk in Ontario cases, [OR: 1.3, 95%CI (1.07–1.68)] and [OR: 1.4, 95%CI (1.07–1.81)], respectively. However, there was neither a statistically significant association nor increased trend of breast cancer risk with COMT^High(ValVal) genotypes in the Finland cases [OR: 1.0, 95%CI (0.73–1.39)]. In the combined analysis, the higher activity alleles of the COMT and CCND1 is associated with increased breast cancer risk in both Ontario [OR: <b>2.22</b>, 95%CI (1.49–3.28)] and Finland [OR: <b>1.73</b>, 95%CI (1.08–2.78)] populations studied. The trend test was statistically significant in both the Ontario and Finland populations across the genotypes associated with increasing enzymatic activity.</p> <p>Conclusion</p> <p>Using two independent Caucasian populations, we have shown a stronger combined effect of the two commonly occurring CCND1 and COMT genotypes in the context of breast cancer predisposition.</p

Navigating the Landscape for Real-time Localisation and Mapping for Robotics, Virtual and Augmented Reality

Visual understanding of 3D environments in real-time, at low power, is a huge computational challenge. Often referred to as SLAM (Simultaneous Localisation and Mapping), it is central to applications spanning domestic and industrial robotics, autonomous vehicles, virtual and augmented reality. This paper describes the results of a major research effort to assemble the algorithms, architectures, tools, and systems software needed to enable delivery of SLAM, by supporting applications specialists in selecting and configuring the appropriate algorithm and the appropriate hardware, and compilation pathway, to meet their performance, accuracy, and energy consumption goals. The major contributions we present are (1) tools and methodology for systematic quantitative evaluation of SLAM algorithms, (2) automated, machine-learning-guided exploration of the algorithmic and implementation design space with respect to multiple objectives, (3) end-to-end simulation tools to enable optimisation of heterogeneous, accelerated architectures for the specific algorithmic requirements of the various SLAM algorithmic approaches, and (4) tools for delivering, where appropriate, accelerated, adaptive SLAM solutions in a managed, JIT-compiled, adaptive runtime context.Comment: Proceedings of the IEEE 201

CD4+ T cell epitopes of FliC conserved between strains of Burkholderia: implications for vaccines against melioidosis and cepacia complex in cystic fibrosis.

Burkholderia pseudomallei is the causative agent of melioidosis characterized by pneumonia and fatal septicemia and prevalent in Southeast Asia. Related Burkholderia species are strong risk factors of mortality in cystic fibrosis (CF). The B. pseudomallei flagellar protein FliC is strongly seroreactive and vaccination protects challenged mice. We assessed B. pseudomallei FliC peptide binding affinity to multiple HLA class II alleles and then assessed CD4 T cell immunity in HLA class II transgenic mice and in seropositive individuals in Thailand. T cell hybridomas were generated to investigate cross-reactivity between B. pseudomallei and the related Burkholderia species associated with Cepacia Complex CF. B. pseudomallei FliC contained several peptide sequences with ability to bind multiple HLA class II alleles. Several peptides were shown to encompass strong CD4 T cell epitopes in B. pseudomallei-exposed individuals and in HLA transgenic mice. In particular, the p38 epitope is robustly recognized by CD4 T cells of seropositive donors across diverse HLA haplotypes. T cell hybridomas against an immunogenic B. pseudomallei FliC epitope also cross-reacted with orthologous FliC sequences from Burkholderia multivorans and Burkholderia cenocepacia, important pathogens in CF. Epitopes within FliC were accessible for processing and presentation from live or heat-killed bacteria, demonstrating that flagellin enters the HLA class II Ag presentation pathway during infection of macrophages with B. cenocepacia. Collectively, the data support the possibility of incorporating FliC T cell epitopes into vaccination programs targeting both at-risk individuals in B. pseudomallei endemic regions as well as CF patients