46 research outputs found

    Maternal hypoxia decreases capillary supply and increases metabolic inefficiency leading to divergence in myocardial oxygen supply and demand

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    Maternal hypoxia is associated with a decrease in left ventricular capillary density while cardiac performance is preserved, implying a mismatch between metabolism and diffusive exchange. We hypothesised this requires a switch in substrate metabolism to maximise efficiency of ATP production from limited oxygen availability. Rat pups from pregnant females exposed to hypoxia (FIO2=0.12) at days 10-20 of pregnancy were grown to adulthood and working hearts perfused ex vivo. 14 C-labelled glucose and 3 H-palmitate were provided as substrates and metabolism quantified from recovery of 14CO2 and 3 H2O, respectively. Hearts of male offspring subjected to Maternal Hypoxia showed a 20% decrease in cardiac output (P<0.05), despite recording a 2-fold increase in glucose oxidation (P<0.01) and 2.5-fold increase (P<0.01) in palmitate oxidation. Addition of insulin to Maternal Hypoxic hearts, further increased glucose oxidation (P<0.01) and suppressed palmitate oxidation (P<0.05), suggesting preservation in insulin signalling in the heart. In vitro enzyme activity measurements showed that Maternal Hypoxia increased both total and the active component of cardiac pyruvate dehydrogenase (both P<0.01), although pyruvate dehydrogenase sensitivity to insulin was lost (NS), while citrate synthase activity declined by 30% (P<0.001) and acetyl-CoA carboxylase activity was unchanged by Maternal Hypoxia, indicating realignment of the metabolic machinery to optimise oxygen utilisation. Capillary density was quantified and oxygen diffusion characteristics examined, with calculated capillary domain area increased by 30% (P<0.001). Calculated metabolic efficiency decreased 4-fold (P<0.01) for Maternal Hypoxia hearts. Paradoxically, the decline in citrate synthase activity and increased metabolism suggest that the scope of individual mitochondria had declined, rendering the myocardium potentially more sensitive to metabolic stress. However, decreasing citrate synthase may be essential to preserve local PO2, minimising regions of hypoxia and hence maximising the area of myocardium able to preserve cardiac output following maternal hypoxia

    ERYTHROPOIETIN FOR THE TREATMENT OF SUBARACHNOID HEMORRAGE: A FEASIBLE INGREDIENT FOR A SUCCESS MEDICAL RECIPE

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    Subaracnhoid hemorrage (SAH) following aneurysm bleeding accounts for 6% to 8% of all cerebrovascular accidents. Althoug an aneurysm can be effectively managed by surgery or endovascular therapy, delayed cerebral ischemia is diagnosed in a high percentage of patients resulting in significant morbility and mortality. Cerebral vasospasm occurs in more than half of all patients after aneurysm rupture and is recognized as the leading cause of delayed cerebral ischemia after SAH. Hemodynamic strategies and endovascular procedures may be considered fo the treatment of cerebral vasospasm. In recent years, the mechanism contributing to the development of vasospasm, abnormal reactivity of cerebral arteries and cerebral ischemia following SAH, have been intensively investigated. A number of pathological processes have been identified in the pathogenesis of vasospasm including endothelial injury, smooth muscle cell contraction from spasmogenic substances produced by the subarachnoid blood clots, changes in vascular responsiveness and inflammatory response of the vascular endothelium. to date, the current therapeutic interventions remain ineffective being limited to the manipulation os systemic blood pressure, variation of blood volume and viscosity, and control of arterial carbon dioxide tension. In this scenario, the hormone erythropoietin (EPO), has been found to exert neuroprotective action during experimental SAH when its recombinant form (rHuEPO) is systematically administered. However, recent translation of experimental data into clinical trials has suggested an unclear role of recombinant human EPO in the setting of SAH. In this context, the aim of the recurrent review is to present current evidence on the potential role of EPO in cerebrovascular dysfunction following aneurysmal subarachnoid hemorrage

    Bacterial biofilm development during experimental degradation of <em>Melicertus kerathurus</em> exoskeleton in seawater

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    Physical inactivity, gender and culture in Arab countries: a systematic assessment of the literature

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    Physical activity and sedentary behaviour in the Middle East and North Africa: An overview of systematic reviews and meta-analysis

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    The Evolution of Educational Technology in Veterinary Anatomy Education.

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    "All learning is in the learner, not the teacher." Plato was right. The adage has passed the test of time and is still true in an era where technology accompanies us in not only professional but also recreational life every day, everywhere. On the other hand, the learner has evolved and so have the sources being used to satisfy curiosity and learning. It therefore appears intuitive to embrace these technological advances to bring knowledge to our pupils with the aim to facilitate learning and improve performance. It must be clear that these technologies are not intended to replace but rather consolidate knowledge partly acquired during more conventional teaching of anatomy. Veterinary medicine is no outlier. Educating students to the complexity of anatomy in multiple species requires that three-dimensional concepts be taught and understood accurately if appropriate treatment is to be set in place thereafter. Veterinary anatomy education has up to recently walked diligently in the footsteps of John Hunter's medical teaching using specimens, textbooks, and drawings. The discipline has yet to embrace fully the benefits of advancement being made in technology for the benefit of its learners. Three-dimensional representation of anatomy is undeniably a logical and correct way to teach whether it is through the demonstration of cadaveric specimen or alternate reality using smartphones, tablets, headsets or other digital media. Here we review some key aspects of the evolution of educational technology in veterinary anatomy
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