39 research outputs found

    Identification of Biologically Relevant Compounds in Aboveground and Belowground Induced Volatile Blends

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    Plants under attack by aboveground herbivores emit complex blends of volatile organic compounds (VOCs). Specific compounds in these blends are used by parasitic wasps to find their hosts. Belowground induction causes shifts in the composition of aboveground induced VOC blends, which affect the preference of parasitic wasps. To identify which of the many volatiles in the complex VOC blends may explain parasitoid preference poses a challenge to ecologists. Here, we present a case study in which we use a novel bioinformatics approach to identify biologically relevant differences between VOC blends of feral cabbage (Brassica oleracea L.). The plants were induced aboveground or belowground with jasmonic acid (JA) and shoot feeding caterpillars (Pieris brassicae or P. rapae). We used Partial Least Squares—Discriminant Analysis (PLSDA) to integrate and visualize the relation between plant-emitted VOCs and the preference of female Cotesia glomerata. Overall, female wasps preferred JA-induced plants over controls, but they strongly preferred aboveground JA-induced plants over belowground JA-induced plants. PLSDA revealed that the emission of several monoterpenes was enhanced similarly in all JA-treated plants, whereas homoterpenes and sesquiterpenes increased exclusively in aboveground JA-induced plants. Wasps may use the ratio between these two classes of terpenes to discriminate between aboveground and belowground induced plants. Additionally, it shows that aboveground applied JA induces different VOC biosynthetic pathways than JA applied to the root. Our bioinformatic approach, thus, successfully identified which VOCs matched the preferences of the wasps in the various choice tests. Additionally, the analysis generated novel hypotheses about the role of JA as a signaling compound in aboveground and belowground induced responses in plants

    Combining qualitative and quantitative understanding for exploring cross-sectoral climate change impacts, adaptation and vulnerability in Europe

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    Climate change will affect all sectors of society and the environment at all scales, ranging from the continental to the national and local. Decision-makers and other interested citizens need to be able to access reliable science-based information to help them respond to the risks of climate change impacts and assess opportunities for adaptation. Participatory integrated assessment (IA) tools combine knowledge from diverse scientific disciplines, take account of the value and importance of stakeholder ‘lay insight’ and facilitate a two-way iterative process of exploration of ‘what if’s’ to enable decision-makers to test ideas and improve their understanding of the complex issues surrounding adaptation to climate change. This paper describes the conceptual design of a participatory IA tool, the CLIMSAVE IA Platform, based on a professionally facilitated stakeholder engagement process. The CLIMSAVE (climate change integrated methodology for cross-sectoral adaptation and vulnerability in Europe) Platform is a user-friendly, interactive web-based tool that allows stakeholders to assess climate change impacts and vulnerabilities for a range of sectors, including agriculture, forests, biodiversity, coasts, water resources and urban development. The linking of models for the different sectors enables stakeholders to see how their interactions could affect European landscape change. The relationship between choice, uncertainty and constraints is a key cross-cutting theme in the conduct of past participatory IA. Integrating scenario development processes with an interactive modelling platform is shown to allow the exploration of future uncertainty as a structural feature of such complex problems, encouraging stakeholders to explore adaptation choices within real-world constraints of future resource availability and environmental and institutional capacities, rather than seeking the ‘right’ answers

    VEGF-A isoforms differentially regulate ATF-2-dependent VCAM-1 gene expression and endothelial-leukocyte interactions

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    Vascular endothelial growth factor A (VEGF-A) regulates many aspects of vascular physiology. VEGF-A stimulates signal transduction pathways that modulate endothelial outputs such as cell migration, proliferation, tubulogenesis, and cell-cell interactions. Multiple VEGF-A isoforms exist, but the biological significance of this is unclear. Here we analyzed VEGF-A isoform-specific stimulation of VCAM-1 gene expression, which controls endothelial-leukocyte interactions, and show that this is dependent on both ERK1/2 and activating transcription factor-2 (ATF-2). VEGF-A isoforms showed differential ERK1/2 and p38 MAPK phosphorylation kinetics. A key feature of VEGF-A isoform-specific ERK1/2 activation and nuclear translocation was increased phosphorylation of ATF-2 on threonine residue 71 (T71). Using reverse genetics, we showed ATF-2 to be functionally required for VEGF-A-stimulated endothelial VCAM-1 gene expression. ATF-2 knockdown blocked VEGF-A-stimulated VCAM-1 expression and endothelial-leukocyte interactions. ATF-2 was also required for other endothelial cell outputs, such as cell migration and tubulogenesis. In contrast, VCAM-1 was essential only for promoting endothelial-leukocyte interactions. This work presents a new paradigm for understanding how soluble growth factor isoforms program complex cellular outputs and responses by modulating signal transduction pathways

    Oral and pharyngeal cancer:Analysis of patient delay at different tumor stages

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    Background. The aim of this study was to examine which factors are related to patient delay in a cohort of consecutive patients with pharyngeal cancer and oral cancer and to determine whether the different stages of patient delay (ie, appraisal, illness, behavioral, and scheduling) were related to different tumor stages. Methods. Before treatment, 55 patients with pharyngeal cancer and 134 patients with oral cancer were interviewed about their prediagnostic period. To verify the data, a questionnaire was sent to the general practitioner and/or dentist and a close relative, Results. Patients with a delay of more than 30 days were significantly more often diagnosed with late-stage (T3-T4) disease (pharynx, p = .01, odds ratio [OR] = 4.5; oral, p =.01, OR = 3.2). No sociodemographic characteristics were associated with patient delay. Conclusions. Prolonged patient delay was associated with late-stage disease for both patients with pharyngeal cancer and patients with oral cancer. Although for most patients the symptoms are vague or might look like a common cold or infection, the general public should be better informed about tumor symptoms. This may enhance earlier visits to a health care professional. (c) 2005 Wiley Periodicals, Inc

    Simultaneous radio- and chemotherapy for squamous cell carcinoma of the head and neck in daily clinical practice: 5 years experience in a University Hospital

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    Several randomized studies and meta-analyses have shown that simultaneous radio- and chemotherapy prolongs survival in patients with unresectable squamous cell carcinoma of the head and neck as compared with conventional radiotherapy. We assessed the feasibility and effectiveness of simultaneous radiotherapy (35 x 2 Gy) and chemotherapy [cisplatinum 100 mg/m(2) or carboplatin (AUC 6) on days 1, 22 and 43] in daily clinical practice in a cohort of 87 patients treated at our institute between 1998 and 2002. Eighty patients completed radiotherapy according to schedule. Eighty patients received two courses of chemotherapy and 50 patients three courses. Nephrotoxity, bone marrow suppression and ototoxicity were the most frequent side-effects. Median weight loss was 8.5%. Median survival was 15 months and 44% of the patients were alive at 2 years. Patients receiving three courses of chemotherapy had a better survival than patients receiving two or less courses. Treatment with simultaneous radio- and chemotherapy for advanced head and neck cancer is a demanding, but feasible treatment in daily clinical practice. Survival seems to be comparable with the results achieved in patients selected for clinical trials

    Simultaneous radio- and chemotherapy for squamous cell carcinoma of the head and neck in daily clinical practice:5 years experience in a University Hospital

    No full text
    Several randomized studies and meta-analyses have shown that simultaneous radio- and chemotherapy prolongs survival in patients with unresectable squamous cell carcinoma of the head and neck as compared with conventional radiotherapy. We assessed the feasibility and effectiveness of simultaneous radiotherapy (35 x 2 Gy) and chemotherapy [cisplatinum 100 mg/m(2) or carboplatin (AUC 6) on days 1, 22 and 43] in daily clinical practice in a cohort of 87 patients treated at our institute between 1998 and 2002. Eighty patients completed radiotherapy according to schedule. Eighty patients received two courses of chemotherapy and 50 patients three courses. Nephrotoxity, bone marrow suppression and ototoxicity were the most frequent side-effects. Median weight loss was 8.5%. Median survival was 15 months and 44% of the patients were alive at 2 years. Patients receiving three courses of chemotherapy had a better survival than patients receiving two or less courses. Treatment with simultaneous radio- and chemotherapy for advanced head and neck cancer is a demanding, but feasible treatment in daily clinical practice. Survival seems to be comparable with the results achieved in patients selected for clinical trials

    MEMBRANE-TRANSPORT OF METHOTREXATE IN A SQUAMOUS CARCINOMA CELL-LINE ADAPTED TO LOW FOLATE CONCENTRATIONS

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    Membrane transport characteristics of the folate analogue methotrexate (MTX) were studied in a human squamous carcinoma cell line of the head and neck (HNSCC) adapted to grow in tissue culture media with nanomolar reduced folate concentrations (SCC-11B-LF), as compared to SCC-11B cells grown in standard medium containing high folate concentrations. We observed that SCC-11B-LF cells exhibited a 10.5-fold increased uptake of [H-3]-MTX via the reduced folate/MTX carrier system compared to SCC-11B cells. Affinity labelling of the reduced folate \MTX carrier system suggests that the up-regulation of [H-3]-MTX transport mainly results from an increased rate of carrier translocation, and only to a minor extent (15-20%) from an increased amount of carrier protein. The upregulation of MTX transport resulted in a 2.4-fold increased growth inhibitory effect by MTX. These results suggest that membrane transport may play a more important role in MTX-cytotoxicity when SCC-11B cells in vitro are grown in more physiological folate concentrations
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