23 research outputs found

    Lack of detectable allergenicity of transgenic maize and soya samples

    Get PDF
    Background: The safety issues regarding foods derived from genetically modified (GM) plants are central to their acceptance into the food supply. The potential allergenicity of proteins newly introduced in GM foods is a major safety concern. Objective: We sought to monitor, in potentially sensitive human populations, the allergenicity effects of 5 GM materials obtained from sources with no allergenic potential and already under commercialization in the European Union. Methods: We have performed skin prick tests with protein extracts prepared from transgenic maize (MON810, Bt11, T25, Bt176) and soya (Roundup Ready) samples and from nontransgenic control samples in 2 sensitive groups: children with food and inhalant allergy and individuals with asthmarhinitis. We have also tested IgE immunoblot reactivity of sera from patients with food allergy to soya (Roundup Ready) and maize (MON810, Bt11, Bt176) samples, as well as to the pure transgenic proteins (CryIA[b] and CP4 5-enolpyruvylshikimate- 3-phosphate synthase). Results: None of the individuals undergoing tests reacted differentially to the transgenic and nontransgenic samples under study. None of the volunteers tested presented detectable IgE antibodies against pure transgenic proteins. Conclusion: The transgenic products under testing seem to be safe in terms of allergenic potential. We propose postmarket testing as an important screening strategy for putative allergic sensitization to proteins introduced in transgenic plants.Supported by Fundação Calouste Gulbenkian, research project SDH.SP.I.01.11 and by Comissão de Fomento da Investigação em Cuidados de Saúde, research project no. 186/0

    Control of allergic rhinitis and asthma test – a formal approach to the development of a measuring tool

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The concurrent management of allergic rhinitis and asthma (ARA) has been recommended by Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. However, a tool capable of assessing simultaneously the control of upper and lower airways diseases is lacking.</p> <p>Aim</p> <p>To describe the studies conducted to design the control of ARA test (CARAT) questionnaire.</p> <p>Methods</p> <p>We performed a literature review to generate a list of potentially important items for the assessment of control of ARA. A formal consensus development process, that used an innovative web-based application, was designed – 111 experts in ARA and 60 patients participated. At the final consensus meeting, 25 primary and secondary care physicians formulated the questions and response options. A qualitative feasibility study (n = 31 patients) was conducted to evaluate the comprehensibility of the questionnaire while testing two different designs.</p> <p>Results</p> <p>Thirty-four potentially important items were identified. All the steps of the consensus process were completed in 2.5 months. The opinions of experts and patients lead to the formulation of 17 questions. At the feasibility study the instructions and wording problems were corrected and a semi-tabular format was chosen.</p> <p>Conclusion</p> <p>A tool to measure the control of allergic rhinitis and asthma was developed using a comprehensive set of methodological steps ensuring the design quality and the face and content validity. Additional validation studies to assess the psychometric properties of the questionnaire have started.</p

    Asymmetric data acquisition system for an endoscopic PET-US detector

    Get PDF
    According to current prognosis studies of pancreatic cancer, survival rate nowadays is still as low as 6% mainly due to late detections. Taking into account the location of the disease within the body and making use of the level of miniaturization in radiation detectors that can be achieved at the present time, EndoTOFPET-US collaboration aims at the development of a multimodal imaging technique for endoscopic pancreas exams that combines the benefits of high resolution metabolic information from time-of- flight (TOF) positron emission tomography (PET) with anatomical information from ultrasound (US). A system with such capabilities calls for an application-specific high-performance data acquisition system (DAQ) able to control and readout data from different detectors. The system is composed of two novel detectors: a PET head extension for a commercial US endoscope placed internally close to the region-of-interest (ROI) and a PET plate placed over the patient's abdomen in coincidence with the PET head. These two detectors will send asymmetric data streams that need to be handled by the DAQ system. The approach chosen to cope with these needs goes through the implementation of a DAQ capable of performing multi-level triggering and which is distributed across two different on-detector electronics and the off-detector electronics placed inside the reconstruction workstation. This manuscript provides an overview on the design of this innovative DAQ system and, based on results obtained by means of final prototypes of the two detectors and DAQ, we conclude that a distributed multi-level triggering DAQ system is suitable for endoscopic PET detectors and it shows potential for its application in different scenarios with asymmetric sources of data

    Design and characterization of the readout ASIC for the BESIII CGEM detector

    Get PDF
    TIGER (Turin Integrated Gem Electronics for Readout) is a mixed-mode ASIC for the readout of signals from CGEM (Cylindrical Gas Electron Multiplier) detector in the upgraded inner tracker of the BESIII experiment, carried out at BEPCII in Beijing. The ASIC includes 64 channels, each of which features a dual-branch architecture optimized for timing and energy measurement. The input signal time-of-arrival and charge measurement is provided by low-power TDCs, based on analogue interpolation techniques, and Wilkinson ADCs, with a fully-digital output. The silicon results of TIGER first prototype are presented showing its full functionality.Peer Reviewe

    Contribution of spatially explicit models to climate change adaptation and mitigation plans for a priority forest habitat

    Get PDF
    Climate change will impact forest ecosystems, their biodiversity and the livelihoods they sustain. Several adaptation and mitigation strategies to counteract climate change impacts have been proposed for these ecosystems. However, effective implementation of such strategies requires a clear understanding of how climate change will influence the future distribution of forest ecosystems. This study uses maximum entropy modelling (MaxEnt) to predict environmentally suitable areas for cork oak (Quercus suber) woodlands, a socio-economically important forest ecosystem protected by the European Union Habitats Directive. Specifically, we use two climate change scenarios to predict changes in environmental suitability across the entire geographical range of the cork oak and in areas where stands were recently established. Up to 40 % of current environmentally suitable areas for cork oak may be lost by 2070, mainly in northern Africa and southern Iberian Peninsula. Almost 90 % of new cork oak stands are predicted to lose suitability by the end of the century, but future plantations can take advantage of increasing suitability in northern Iberian Peninsula and France. The predicted impacts cross-country borders, showing that a multinational strategy, will be required for cork oak woodland adaptation to climate change. Such a strategy must be regionally adjusted, featuring the protection of refugia sites in southern areas and stimulating sustainable forest management in areas that will keep long-term suitability. Afforestation efforts should also be promoted but must consider environmental suitability and land competition issues

    C19. Ventilação mecânica prolongada numa UCI respiratória

    Get PDF
    Os autores tiveram como objectivo avaliar a ventilação mecânica prolongada (VMP) (³ 15 dias) tendo em consideração: - grupos de diagnóstico, gravidade e sobrevivência.De 1990 a 2002 todos os doentes submetidos a ventilação mecânica (VM) admitidos na nossa UCI foram incluídos. Os doentes com VM ³ 15 e 0.05Dos doentes com VMP que tiveram alta (n=236), 13 (5,5%) ficaram dependentes de VM invasiva; 26 (11%) faleceram após 40,1±38 meses e 104 (44%) estavam vivos ao fim de 21±29,9 meses após a alta.Em conclusão os doentes com VMP tiveram uma maior taxa de mortalidade durante o internamento na UCI. apesar de terem APACHE II idênticos. Daqueles que sobreviveram somente 5,5% ficaram dependentes VM invasiva. No follow-up 44% dos doentes com VMP estavam vivos após 21 meses. : Our aim was to evaluate prolonged mechanical ventilation (PMV) (³ 15 days) in what concerns:- diagnostic groups, severity and survival.During 1990-2002 all mechanically ventilated (MV) patients admitted in the study period were included. MV ³ 15 and 0.05From discharged patients (n=236), 13 (5,5%) were dependent on invasive MV; 26 (11%) died in a 40,1±38 months period and 104 (44%) were alive in 21±29,9 months after discharge.In conclusion in spite of a similar APACHE II, PMV patients had higher ICU mortality rate. From survivors only 5,5% rested dependent on invasive MV. The follow-up of PMV showed a 44% survival rate at more or less 21 months. Key words: prolonged mechanical ventilation, follow-up, Palavras chave: ventilação mecânica prolongada, follow-u

    Detection sensitivity and light collection studies of an APD-based high packing-fraction LYSO:Ce matrix for PET applications

    No full text
    The ClearPEM is a dedicated APD-based PET detector for high-resolution breast cancer imaging. The detector module is composed of 12 LYSO:Ce crystal matrices, each with 4 x 8 individual crystals (2 x 2 x 20 mm(3)) optically coupled on both ends to S8550 Hamamatsu APD arrays for the scintillation light readout. Only 46% of the sensitive area of the detector is constituted by LYSO crystals. The inactive area is due to gaps between APD matrices, encapsulation and BaSO4 reflective walls. To improve the overall sensitivity of the system, a new compact crystal matrix geometry was designed to minimise these inactive parts. In the new crystal matrix geometry, 76% of the sensitive area of the detector is constituted by LYSO:Ce crystals and crystals with three different dimensions are needed. The different matching factors of cross-section between the APDs and the crystals require a study on the effects on the energy and time resolution, optical cross-talk and on depth-of-interaction capability. In this paper, we present an experimental study on the improvement of the sensitivity with this new compact matrix, and a characterisation of its effects on the overall detector performance. (C) 2013 Elsevier B.V. All rights reserved
    corecore