307 research outputs found

    Molecular Engineering of the Autographa californica Nuclear Polyhedrosis Virus Genome: Deletion Mutations Within the Polyhedrin Gene

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    We describe a method to introduce site-specific mutations into the genome of Autographa californica nuclear polyhedrosis virus. Specifically, the A. californica nuclear polyhedrosis virus gene for polyhedrin, the major protein that forms viral occlusions in infected cells, was mutagenized by introducing deletions into the cloned DNA fragment containing the gene. The mutagenized polyhedrin gene was transferred to the intact viral DNA by mixing fragment and viral DNAs, cotransfecting Spodoptera frugiperda cells, and screening for viral recombinants that had undergone allelic exchange. Recombinant viruses with mutant polyhedrin genes were obtained by selecting the progeny virus that did not produce viral occlusions in infected cells (occlusion-negative mutants). Analyses of occlusion-negative mutants demonstrated that the polyhedrin gene was not essential for the production of infectious virus and that deletion of certain sequences within the gene did not alter the control, or decrease the level of expression, of polyhedrin. An early viral protein of 25,000 molecular weight was apparently not essential for virus replication in vitro, as the synthesis of this protein was not detected in cells infected with a mutant virus

    Glucose absorption and gastric emptying in critical illness

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    Introduction: Delayed gastric emptying occurs frequently in critically ill patients and has the potential to adversely affect both the rate, and extent, of nutrient absorption. However, there is limited information about nutrient absorption in the critically ill, and the relationship between gastric emptying (GE) and absorption has hitherto not been evaluated. The aim of this study was to quantify glucose absorption and the relationships between GE, glucose absorption and glycaemia in critically ill patients. Methods: Studies were performed in nineteen mechanically ventilated critically ill patients and compared to nineteen healthy subjects. Following 4 hours fasting, 100 ml of Ensure, 2 g 3-Omethyl glucose (3-OMG) and ⁹⁹mTc sulphur colloid were infused into the stomach over 5 minutes. Glucose absorption (plasma 3- OMG), blood glucose levels and GE (scintigraphy) were measured over four hours. Data are mean ± SEM. A P-value 0.51; P < 0.05). Conclusions In critically ill patients; (i) the rate and extent of glucose absorption are markedly reduced; (ii) GE is a major determinant of the rate of absorption, but does not fully account for the extent of impaired absorption; (iii) blood glucose concentration could be one of a number of factors affecting GE.Marianne J Chapman, Robert JL Fraser, Geoffrey Matthews, Antonietta Russo, Max Bellon, Laura K Besanko, Karen L Jones, Ross Butler, Barry Chatterton and Michael Horowit

    Bone turnover and metabolite responses to exercise in people with and without long-duration type 1 diabetes: a case-control study

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    INTRODUCTION: Exercise acutely alters markers of bone resorption and formation. As risk of fracture is increased in patients with type 1 diabetes, understanding if exercise-induced bone turnover is affected within this population is prudent. We assessed bone turnover responses to acute exercise in individuals with long-duration type 1 diabetes and matched controls. RESEARCH DESIGN AND METHODS: Participants with type 1 diabetes (n=15; age: 38.7±13.3; glycosylated hemoglobin: 60.5±6.7 mmol/mol; diabetes duration: 19.3±11.4 years) and age-matched, fitness-matched, and body mass index-matched controls (n=15) completed 45 min of incline walking (60% peak oxygen uptake). Blood samples were collected at baseline and immediately, 30 min, and 60 min postexercise. Markers of bone resorption (β-C-terminal cross-linked telopeptide of type 1 collagen, β-CTx) and formation (procollagen type-1 amino-terminal propeptide, P1NP), parathyroid hormone (PTH), phosphate, and calcium (albumin-adjusted and ionized) were measured. Data (mean±SD) were analyzed by a mixed-model analysis of variance. RESULTS: Baseline concentrations of P1NP and β-CTx were comparable between participants with type 1 diabetes and controls. P1NP did not change with exercise (p=0.20) but β-CTx decreased (p0.39). Participants with type 1 diabetes had reduced albumin and ionized calcium at all sample points (p<0.01). CONCLUSIONS: Following exercise, participants with type 1 diabetes displayed similar time-course changes in markers of bone formation and associated metabolites, but an attenuated suppression in bone resorption. The reduced albumin and ionized calcium may have implications for future bone health. Further investigation of the interactions between type 1 diabetes, differing modalities and intensities of exercise, and bone health is warranted

    Whose Power to Control? Some Reflections on Seed Systems and Food Security in a Changing World

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    Four key words are essential in understanding the changing global food system: power, control, risks and benefits. The interplay between state and private actors vying to influence the direction of change, and use whatever tools for control they can, is at the heart of the contention for the future control of food. It is one shaped by history and influenced by a changing geopolitics. This interplay has led to the creation of a range of global rules affecting food, agriculture and biodiversity in which those on ‘intellectual property’ or IP are central. These rules come from a system dominated by the interests of the biggest players. Also important are the changing understandings and nature of food security and the pathways to innovation in agri?food systems that are most likely to lead to a just, healthy and sustainable future for all. Developments in food and farming are central to this and are the context in which the political economy of cereal seed systems in Africa is grounded

    Artenvielfalt auf biologischen und nicht-biologischen Landwirtschaftsbetrieben in zehn europäischen Regionen

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    One of the aims of organic farming is the protection of biodiversity. In the EU FP7 project BioBio, we studied the effect of organic farming on species numbers at farm level on 169 randomly selected organic and non-organic farms with mostly low to medium intensity in ten European regions. Using a preferential sampling scheme based on habitat mapping, numbers of plants, earthworms, spiders and bees were assessed at farm level. A global analysis across the ten regions shows that organic farms have significantly higher numbers of plant and bee species than non-organic farms. The effect of organic farming on earthworm and spider species numbers are also positive but insignificant. The effects in absolute terms are small and much smaller than the variation between individual farms. Currently ongoing analyses aim at identifying the important driving factors for farmland biodiversity

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

    Genomic and molecular analyses identify molecular subtypes of pancreatic cancer recurrence

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    Pancreatic cancer (PC) remains a highly lethal malignancy, and most patients with localized disease that undergo surgical resection still succumb to recurrent disease. Pattern of recurrence after pancreatectomy is heterogenous, with some studies illustrating that site of recurrence can be associated with prognosis.1 Another study suggested that tumors that develop local and distant recurrence can be regarded as a homogenous disease with similar outcomes.2 Here we investigate novel molecular determinants of recurrence pattern after pancreatectomy for PC
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