Browsing by Subject "Fatty acids"

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    Open Access
    Infarct size and free fatty acids in the early phase of acute myocardial infarction
    (1980) Tansey, M J B; Opie, Lionel H
    The management of acute myocardial infarction (AMI) has been improved by the realisation that the size of infarction can influence mortality (Sobel et al, 1972) and that the infarct size can be altered by subsequent therapy (Maroko et al, 1972). The identification of any factor which may have adverse effects on the ischaemic myocardium and which is amenable to treatment would therefore have important prognostic implications. Elevation of circulating free fatty acid (FFA) concentrations is a consistent feature (Kurien and Oliver, 1966; Oliver et al, 1968) of the profound, non-specific metabolic reaction associated with the onset of AMI (Opie, 1975). The FFA rise has been correlated with the development of arrhythmias (Oliver et al, 1968) after AMI, and with the severity of ischaemic damage (Oliver et al, 1968; Gupta et al, 1969; Russell & Oliver, 1978) on clinical grounds. The method of quantifying infarct size developed by Shell et al (1972) has provided a means of correlating the degree of metabolic disturbance with extent of myocardial damage, and of assessing the benefits of metabolic interventions. The purpose of the studies reported in this thesis was to examine in detail the FFA rise in the early phase of AMI and to correlate this rise with the development of arrhythmias and other complications of AMI and with enzymatically estimated infarct size, thus leading to a more rational approach to therapeutic interventions.
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    Open Access
    Spatio-temporal variation in effects of upwelling on the fatty acid composition of benthic filter feeders in the Southern Benguela ecosystem: not all upwelling is equal
    (Public Library of Science, 2016) Puccinelli, Eleonora; McQuaid, Christopher David; Noyon, Margaux
    Variability in mesoscale nearshore oceanographic conditions plays an important role in the distribution of primary production and food availability for intertidal consumers. Advection of nutrient rich waters by upwelling usually allows the proliferation of diatoms, later replaced by dinoflagellates. We examined upwelling effects on the fatty acid (FA) signature of a benthic intertidal filter feeder to identify its response to pulsed variability in food availability. The study took place in two contrasting seasons and at two upwelling and two non-upwelling sites interspersed within the southern Benguela upwelling system of South Africa. We investigated the FA composition of the adductor muscles and gonads of the mussel Mytilus galloprovincialis to assess how FA are apportioned to the different tissues and whether this changes between upwelling and non-upwelling conditions. In situ temperature loggers used to identify upwelling conditions at the four sites indicated that such events occurred only at the upwelling centres and only in summer. Tissues differed strongly, with gonads presenting a higher proportion of essential FAs. This could reflect the faster turnover rate of gonad tissue or preferential retention of specific FA for reproductive purposes. FA composition did not vary as a direct function of upwelling, but there were strong dissimilarities among sites. Upwelling influenced mussel diets at one upwelling site while at the other, the expected signature of upwelling was displaced downstream of the core of upwelling. Condition Index (CI) and Gonad Index (GI) differed among sites and were not influenced by upwelling, with GI being comparable among sites. In addition, FA proportions were consistent among sites, indicating similar food quality and quantity over time and under upwelling and non-upwelling conditions. This suggests that the influence of upwelling on the west coast of South Africa is pervasive and diffuse, rather than discrete; while nearshore retention or advection of upwelled water is critical and site-specific so that the effects of upwelling differ even among sites categorised as upwelling centres.
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    Open Access
    The common fatty acids of human depot fat
    (1961) Krut, Louis Harold
    The current renaissance in biological research has evoked widespread interest in the field of lipid metabolism. While extensive studies during the past decade have greatly expanded our knowledge of the subject, these researches have been directed primarily to the serum lipids. By far the greatest accumulation of lipid in the mammalian organism is found in the depot fat. This tissue had, until fairly recently, been generally regarded as a semi-static food store, expanding and shrinking in response to a relative excess or deficit of dietary calories. This simple concept is no longer tenable. The pioneering work of a few workers in the field during the past few decades has more recently interested many others and the accumulated evidence has established the fat depot among the more active organs in the mamnalian organism.