474 research outputs found

    Is there a hypercoagulable state after off-pump coronary artery bypass surgery? What do we know and what can we do?

    Get PDF

    Assessment of the in vitro antithrombotic properties of sardine (sardina pilchardus) fillet lipids and cod liver oil

    Get PDF
    peer-reviewedThe aim of the current study was to compare the biological activities of total polar lipids (TPL) and thin-layer chromatography (TLC) polar lipid fractions of sardine fillet and cod liver oil against atherogenesis. TPL and TLC polar lipid fractions obtained from these two sources were assessed for their ability to inhibit the platelet-activating-factor (PAF)-induced platelet aggregation (PAF-antagonists) or to induce platelet aggregation (PAF-agonists), since PAF plays a crucial role in the initiation and development of atherosclerosis. This study focused on the polar lipids since previous studies have underlined that the antithrombotic properties of foodstuffs are mainly attributed to polar lipid micro-constituents. TPL of sardine fillet induced platelet aggregation, while TPL of cod liver had a bimodal effect on platelets. TLC polar lipid fractions of both samples exhibited in vitro aggregatory and inhibitory activity towards platelets. However, TLC sardine polar lipid fractions showed stronger in vitro antithrombotic activities than the cod liver oil ones. These data constitute evidence of the putative contribution of fish polar lipids against cardiovascular diseases, underling firstly the beneficial effect of fish and fish lipids as functional foodstuffs against atherogenesis and secondly the more important role of sardine polar lipids as opposed to cod liver oil.PUBLISHEDpeer-reviewe

    Non-Invasive Technology That Improves Cardiac Function after Experimental Myocardial Infarction: Whole Body Periodic Acceleration (pGz)

    Get PDF
    Myocardial infarction (MI) may produce significant inflammatory changes and adverse ventricular remodeling leading to heart failure and premature death. Pharmacologic, stem cell transplantation, and exercise have not halted the inexorable rise in the prevalence and great economic costs of heart failure despite extensive investigations of such treatments. New therapeutic modalities are needed. Whole Body Periodic Acceleration (pGz) is a non-invasive technology that increases pulsatile shear stress to the endothelium thereby producing several beneficial cardiovascular effects as demonstrated in animal models, normal humans and patients with heart disease. pGz upregulates endothelial derived nitric oxide synthase (eNOS) and its phosphorylation (p-eNOS) to improve myocardial function in models of myocardial stunning and preconditioning. Here we test whether pGz applied chronically after focal myocardial infarction in rats improves functional outcomes from MI. Focal MI was produced by left coronary artery ligation. One day after ligation animals were randomized to receive daily treatments of pGz for four weeks (MI-pGz) or serve as controls (MI-CONT), with an additional group as non-infarction controls (Sham). Echocardiograms and invasive pressure volume loop analysis were carried out. Infarct transmurality, myocardial fibrosis, and markers of inflammatory and anti-inflammatory cytokines were determined along with protein analysis of eNOS, p-eNOS and inducible nitric oxide synthase (iNOS).At four weeks, survival was 80% in MI-pGz vs 50% in MI-CONT (p< 0.01). Ejection fraction and fractional shortening and invasive pressure volume relation indices of afterload and contractility were significantly better in MI-pGz. The latter where associated with decreased infarct transmurality and decreased fibrosis along with increased eNOS, p-eNOS. Additionally, MI-pGz had significantly lower levels of iNOS, inflammatory cytokines (IL-6, TNF-α), and higher level of anti-inflammatory cytokine (IL-10). pGz improved survival and contractile performance, associated with improved myocardial remodeling. pGz may serve as a simple, safe, non-invasive therapeutic modality to improve myocardial function after MI

    Productivity responses of a widespread marine piscivore, Gadus morhua, to oceanic thermal extremes and trends

    Get PDF
    Climate change will have major consequences for population dynamics and life histories of marine biota as it progresses in the twenty-first century. These impacts will differ in magnitude and direction for populations within individual marine species whose geographical ranges span large gradients in latitude and temperature. Here we use meta-analytical methods to investigate how recruitment (i.e. the number of new fish produced by spawners in a given year which subsequently grow and survive to become vulnerable to fishing gear) has reacted to temperature fluctuations, and in particular to extremes of temperature, in cod populations throughout the north Atlantic. Temperature has geographically explicit effects on cod recruitment. Impacts differ depending on whether populations are located in the upper (negative effects) or in the lower (positive effects) thermal range. The probabilities of successful year-classes in populations living in warm areas is on average 34 per cent higher in cold compared with warm seasons, whereas opposite patterns exist for populations living in cold areas. These results have implications for cod dynamics, distributions and phenologies under the influence of ocean warming, particularly related to not only changes in the mean temperature, but also its variability (e.g. frequency of exceptionally cold or warm seasons)

    Basket Cases and Breadbaskets: Sacred Rice and Agricultural Development in Postcolonial Africa

    Full text link
    Author's final manuscript.Based on ethnographic research among rural Diola in Guinea-Bissau, I provide a broad view of the history and interpenetration of rice in social, political, religious, and ecological domains, while chronicling the current difficulties of residents in this region who are no longer able to grown enough of it. These farmers’ experiences are unfolding at a time of revitalized attention to agricultural development in Africa, particularly under the auspices of the New Green Revolution for Africa. I examine the premises that constitute the resuscitated effort to address the plight of African farmers. I argue that the totalizing quality of rice in Diola and other rice-cultivating societies requires a development approach that takes into account dimensions of agrarian life not encapsulated by the high- modernist and anti-political orientation of the New Green Revolution for Africa

    End-to-end foodweb control of fish production on Georges Bank

    Get PDF
    Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Oxford University Press for personal use, not for redistribution. The definitive version was published in ICES Journal of Marine Science: Journal du Conseil 66 (2009): 2223-2232, doi:10.1093/icesjms/fsp180.The ecosystem approach to management requires the productivity of individual fish stocks to be considered in the context of the entire ecosystem. In this paper, we derive an annual end-to-end budget for the Georges Bank ecosystem, based on data from the GLOBEC program and fisheries surveys for the years 1993-2002. We use this budget as the basis to construct scenarios that describe the consequences of various alterations in the Georges Bank trophic web: reduced nutrient input, increased benthic production, removal of carnivorous plankton such as jellyfish, and changes in species dominance within fish guilds. We calculate potential yields of cod and haddock for the different scenarios, and compare the results with historic catches and estimates of maximum sustainable yield (MSY) from recent stock assessments. The MSYs of cod and haddock can be met if the fish community is restructured to make them the dominant species in their respective diet-defined guilds. A return to the balance of fish species present in the first half of the 20th century would depend on an increase in the fraction of primary production going to the benthos rather than to plankton. Estimates of energy flux through the Georges Bank trophic web indicate that rebuilding the principal groundfish species to their MSY levels requires restructuring of the fish community and repartitioning of energy within the food web.We acknowledge NOAA-CICOR award NA17RJ1233 (J.H. Steele) and NSF award OCE0217399 (D.J. Gifford and J.S. Collie)

    Protocol for the Arterial Revascularisation Trial (ART). A randomised trial to compare survival following bilateral versus single internal mammary grafting in coronary revascularisation [ISRCTN46552265]

    Get PDF
    BACKGROUND: Standard coronary artery bypass graft surgery uses a single internal mammary artery and supplemental vein or radial artery grafts. Several observational studies have suggested a survival benefit with two internal mammary artery grafts compared to a single internal mammary artery graft, but this has not been tested in a randomised trial. The Arterial Revascularisation Trial is a Medical Research Council and British Heart Foundation funded, multi-centre international trial comparing single internal mammary artery grafting versus bilateral internal mammary artery grafting. METHODS/DESIGN: Twenty centres in the UK, Australia, Poland and Brazil are planning to randomise 3000 coronary artery bypass graft surgery patients to single or bilateral internal mammary artery grafting. Supplemental grafts may be either saphenous vein or radial artery. Coronary artery bypass grafting can be performed as an on-pump or off-pump procedure. The primary outcome is survival at 10 years and secondary end-points include clinical events, quality of life and cost effectiveness. The effect of age, left ventricular function, diabetes, number of grafts, vein grafts and off-pump surgery are pre-specified subgroups. DISCUSSION: The Arterial Revascularisation Trial is one of the first randomised trials to evaluate the effects on survival and other clinical outcomes of single internal mammary artery grafting versus bilateral internal mammary artery grafting, and will help to establish the best approach for patients requiring coronary artery bypass graft surgery

    Identification and characterisation of novel SNP markers in Atlantic cod: Evidence for directional selection

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>The Atlantic cod (<it>Gadus morhua</it>) is a groundfish of great economic value in fisheries and an emerging species in aquaculture. Genetic markers are needed to identify wild stocks in order to ensure sustainable management, and for marker-assisted selection and pedigree determination in aquaculture. Here, we report on the development and evaluation of a large number of Single Nucleotide Polymorphism (SNP) markers from the alignment of Expressed Sequence Tag (EST) sequences in Atlantic cod. We also present basic population parameters of the SNPs in samples of North-East Arctic cod and Norwegian coastal cod obtained from three different localities, and test for SNPs that may have been targeted by natural selection.</p> <p>Results</p> <p>A total of 17,056 EST sequences were used to find 724 putative SNPs, from which 318 segregating SNPs were isolated. The SNPs were tested on Atlantic cod from four different sites, comprising both North-East Arctic cod (NEAC) and Norwegian coastal cod (NCC). The average heterozygosity of the SNPs was 0.25 and the average minor allele frequency was 0.18. <it>F</it><sub><it>ST </it></sub>values were highly variable, with the majority of SNPs displaying very little differentiation while others had <it>F</it><sub><it>ST </it></sub>values as high as 0.83. The <it>F</it><sub><it>ST </it></sub>values of 29 SNPs were found to be larger than expected under a strictly neutral model, suggesting that these loci are, or have been, influenced by natural selection. For the majority of these outlier SNPs, allele frequencies in a northern sample of NCC were intermediate between allele frequencies in a southern sample of NCC and a sample of NEAC, indicating a cline in allele frequencies similar to that found at the Pantophysin I locus.</p> <p>Conclusion</p> <p>The SNP markers presented here are powerful tools for future genetics work related to management and aquaculture. In particular, some SNPs exhibiting high levels of population divergence have potential to significantly enhance studies on the population structure of Atlantic cod.</p

    Balancing end-to-end budgets of the Georges Bank ecosystem

    Get PDF
    Author Posting. © Elsevier, 2007. This is the author's version of the work. It is posted here by permission of Elsevier for personal use, not for redistribution. The definitive version was published in Progress In Oceanography 74 (2007): 423-448, doi:10.1016/j.pocean.2007.05.003.Oceanographic regimes on the continental shelf display a great range in the time scales of physical exchange, biochemical processes and trophic transfers. The close surface-to-seabed physical coupling at intermediate scales of weeks to months means that the open ocean simplification to a purely pelagic food web is inadequate. Top-down trophic depictions, starting from the fish populations, are insufficient to constrain a system involving extensive nutrient recycling at lower trophic levels and subject to physical forcing as well as fishing. These pelagic-benthic interactions are found on all continental shelves but are particularly important on the relatively shallow Georges Bank in the northwest Atlantic. We have generated budgets for the lower food web for three physical regimes (well mixed, transitional and stratified) and for three seasons (spring, summer and fall/winter). The calculations show that vertical mixing and lateral exchange between the three regimes are important for zooplankton production as well as for nutrient input. Benthic suspension feeders are an additional critical pathway for transfers to higher trophic levels. Estimates of production by mesozooplankton, benthic suspension feeders and deposit feeders, derived primarily from data collected during the GLOBEC years of 1995-1999, provide input to an upper food web. Diets of commercial fish populations are used to calculate food requirements in three fish categories, planktivores, benthivores and piscivores, for four decades, 1963-2002, between which there were major changes in the fish communities. Comparisons of inputs from the lower web with fish energetic requirements for plankton and benthos indicate that we obtained reasonable agreement for the last three decades, 1973 to 2002. However, for the first decade, the fish food requirements were significantly less than the inputs. This decade, 1963-1972, corresponds to a period characterized by a strong Labrador Current and lower nitrate levels at the shelf edge, demonstrating how strong bottom-up physical forcing may determine overall fish yields.The research was done under the aegis of the U.S.-GLOBEC Northwest Atlantic Georges Bank Study, a program sponsored jointly by the U.S. National Science Foundation and the U.S. National Oceanic and Atmospheric Administration. We acknowledge NOAA-CICOR award NA17RJ1233 (J.H. Steele), NSF awards OCE0217399 (D.J. Gifford), OCE0217122 (J.J. Bisagni) and OCE0217257 (M.E. Sieracki). W.T. Stockhausen was supported by the NOAA Sponsored Coastal Ocean Research Program
    corecore