608 resultados para Dehner, Dorothy


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Objective: Excess levels of free radicals such as nitric oxide (NO) and superoxide anion (O2-)are associated with the pathogenesis of endothelial cell dysfunction in diabetes mellitus. This study was designed to investigate the underlying causes of oxidative stress in coronary microvascular endothelial cells (CMEC) exposed to hyperglycaemia. Methods: CMEC were cultured under normal (5.5 mmol/L) or high glucose (22 mmol/L)concentrations for 7 days. The activity and expression (protein level) of eNOS, iNOS, NAD(P)H oxidase and antioxidant enzymes, namely, superoxide dismutase (SOD), catalase and glutahione peroxidase (GPx) were investigated by specific activity assays and Western analyses,respectively while the effects of hyperglycaemia on nitrite and O2 - generation were investigated by Griess reaction and cytochrome C reduction assay, respectively. Results: Hyperglycaemia did not alter eNOS or iNOS protein expressions and overall nitrite generation, an index of NO production. However, it significantly reduced the levels of intracellular antioxidant glutathione by 50% (p<0.05) and increased the protein expressions and/or activities of p22-phox, a membrane-bound component of pro-oxidant NAD(P)H oxidase and antioxidant enzymes (p<0.05). Free radical-scavengers, namely, Tiron and MPG (0.1-1 mol/L) reduced hyperglycaemia-induced antioxidant enzyme activity and increased glutathione and nitrite generation to the levels observed in CMEC cultured in normoglycaemic medium (p<0.01). The differences in enzyme activity and expressions were independent of the increased osmolarity generated by high glucose levels as investigated by using equimolar concentrations of mannitol in parallel experiments. Conclusions: These results suggest that hyperglycaemia-induced oxidative stress may arise in CMEC as a result of enhanced prooxidant enzyme activity and diminished generation of 3 antioxidant glutathione. By increasing the antioxidant enzyme capacity CMEC may protect themselves against free radical-induced cell damage in diabetic conditions. The definitive version is available at http://www.blackwell-synergy.com

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This thesis examines the early stages of the transformation of emblematic political prints into political caricature from the beginning of the Seven Years' War (1756) to the Treaty of Paris, which ended the American Revolutionary War (1783). Both contextual and iconographical issues are investigated in relation to the debates occasioned by Britain's imperial project, which marked a period of dramatic expansion during the Seven Years' War, and ended with the loss of the American colonies, consequently framing this thesis as a study of political prints during the rise and fall of the so-called 'First British Empire'. Previous studies of eighteenth-century political prints have largely ignored the complex and lengthy evolutionary process by which the emblematic mode amalgamated with caricatural representation, and have consequently concluded that political prints excluded emblems entirely by the end of the 1770s. However, this study emphasizes the significance of the Wilkite movement for the promotion and preservation of emblems, and investigates how pictorial political argument was perceived and received in eighteenth-century British society, arguing that wider tastes and opinions regarding the utilization of political prints gradually shifted to accept both modes of representation. Moreover, the marketplace, legal status, topicality, and manufacturing methods of political prints are analyzed in terms of understanding the precarious nature of their consumption and those that endeavoured to engage in political printmaking. The evolution, establishment, and subsequent appropriation of pictorial tropes is discussed from the early modern period to the beginning of the so-called Golden Age of caricature, while tracing the adaptation of representational models in American colonial prints that employed emblems already entrenched in British pictorial political debate. Political prints from the two largest print collections, the British Museum and the Lewis Walpole Library at Yale are consulted, along with a number of eighteenth-century newspapers and periodicals, to develop the earlier research by M. Dorothy George, Charles Press, Herbert Atherton, Diana Donald, Amelia Rauser, and Eirwen Nicholson.

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Le système vestibulaire et le cortex moteur participent au contrôle de la posture, mais la nature de leurs interactions est peu documentée. Afin de caractériser les interactions vestibulo-corticales qui sous-tendent le contrôle de l’équilibre en position debout, l’activité électromyographique (EMG) du soléaire (SOL), du tibial antérieur (TA) et du péronier long (PERL) de la jambe droite a été enregistrée chez 14 sujets sains. La stimulation galvanique vestibulaire (GVS) a été appliquée avec la cathode derrière l’oreille droite ou gauche à différents intervalles inter-stimulus (ISIs) avant ou après la stimulation magnétique transcrânienne induisant des potentiels moteurs évoqués (MEPs) au niveau des muscles enregistrés. Lorsque que la cathode était à droite, une inhibition des MEPs a été observée au niveau du SOL à un ISI de 40 et 130 ms et une facilitation des MEPS a été observée au niveau TA à un ISI de 110 ms. Lorsque la cathode était à gauche, une facilitation des MEPs a été observée au niveau du SOL, du TA et du PERL à un ISI de 50, -10 et 0 ms respectivement. L’emplacement de ces interactions sur l’axe neural a été estimé en fonction des ISIs et en comparant l’effet de la GVS sur les MEPs à son effet sur l’EMG de base et sur le réflexe-H. Selon ces analyses, les modulations observées peuvent avoir lieu au niveau spinal ou au niveau supraspinal. Ces résultats suggèrent que les commandes de la voie corticospinale peuvent être modulées par le système vestibulaire à différents niveaux de l’axe neuronal.

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Purpose: The purpose of this paper is to present the application of logical framework analysis (LFA) for implementing continuous quality improvement (CQI) across multiple settings in a tertiary care hospital. Design/methodology/approach: This study adopts a multiple case study approach. LFA is implemented within three diverse settings, namely, intensive care unit, surgical ward, and acute in-patient psychiatric ward. First, problem trees are developed in order to determine the root causes of quality issues, specific to the three settings. Second, objective trees are formed suggesting solutions to the quality issues. Third, project plan template using logical framework (LOGFRAME) is created for each setting. Findings: This study shows substantial improvement in quality across the three settings. LFA proved to be effective to analyse quality issues and suggest improvement measures objectively. Research limitations/implications: This paper applies LFA in specific, albeit, diverse settings in one hospital. For validation purposes, it would be ideal to analyse in other settings within the same hospital, as well as in several hospitals. It also adopts a bottom-up approach when this can be triangulated with other sources of data. Practical implications: LFA enables top management to obtain an integrated view of performance. It also provides a basis for further quantitative research on quality management through the identification of key performance indicators and facilitates the development of a business case for improvement. Originality/value: LFA is a novel approach for the implementation of CQI programs. Although LFA has been used extensively for project development to source funds from development banks, its application in quality improvement within healthcare projects is scant.

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Le système vestibulaire et le cortex moteur participent au contrôle de la posture, mais la nature de leurs interactions est peu documentée. Afin de caractériser les interactions vestibulo-corticales qui sous-tendent le contrôle de l’équilibre en position debout, l’activité électromyographique (EMG) du soléaire (SOL), du tibial antérieur (TA) et du péronier long (PERL) de la jambe droite a été enregistrée chez 14 sujets sains. La stimulation galvanique vestibulaire (GVS) a été appliquée avec la cathode derrière l’oreille droite ou gauche à différents intervalles inter-stimulus (ISIs) avant ou après la stimulation magnétique transcrânienne induisant des potentiels moteurs évoqués (MEPs) au niveau des muscles enregistrés. Lorsque que la cathode était à droite, une inhibition des MEPs a été observée au niveau du SOL à un ISI de 40 et 130 ms et une facilitation des MEPS a été observée au niveau TA à un ISI de 110 ms. Lorsque la cathode était à gauche, une facilitation des MEPs a été observée au niveau du SOL, du TA et du PERL à un ISI de 50, -10 et 0 ms respectivement. L’emplacement de ces interactions sur l’axe neural a été estimé en fonction des ISIs et en comparant l’effet de la GVS sur les MEPs à son effet sur l’EMG de base et sur le réflexe-H. Selon ces analyses, les modulations observées peuvent avoir lieu au niveau spinal ou au niveau supraspinal. Ces résultats suggèrent que les commandes de la voie corticospinale peuvent être modulées par le système vestibulaire à différents niveaux de l’axe neuronal.